Study on Chemical Coprecipitation Synthesis of Sr4Al14O25: Eu～(2+), Dy～(3+) Long Afterglow Phosphors

Study on Chemical Coprecipitation Synthesis of Sr4Al14O25: Eu～(2+), Dy～(3+) Long Afterglow Phosphors
　　The aluminate-based phosphors have intensely interested people becausethey have excellent properties such as high luminescent efficiency, stablechemical properties. Before the 1970s the most phosphors studied were silicate,phosphate and sulfide. Because it was easy to get high-purity silicate, alkalineearth carbonate and alkaline earth phosphate but lack of high-purityaluminium oxide in fine grain size. In 1974 Dutch Verstegen synthesized(BaMgEu)3Al16O27 blue phosphor activated by rare earth, this made the usageof phosphors used as by fluorescent lamp and promoted the development ofaluminate based phosphors with long afterglow.At present, CaAl2O4:Eu,Nd, SrAl2O4:Eu,Dy and Sr4Al14O25:Eu,Dyprepared by solid state method have been applied in practical living. Block Neodymium magnets Hightemperature solid state method is the earliest and the most common method toprepare the strontium aluminates based phosphors with long afterglow, and itis the only method to realize commercial process. The preparing ofSr4Al14O25:Eu,Dy is mostly via solid state method. But this method has itselfdefect.
　　The sintering temperature is higher, from 1300℃ to 1600℃, sometimesit can arrive 1700℃;The reaction needs long time, about 6 to 8 hours;Thephosphor has large grain size , high density, high hardness. In the practicalapplication, the phosphors have to be ground and this impossibly destroy thecrystal lattice structure, so it can impact luminescent brightness and afterglowproperties, even make luminescent properties descend obviously. In order toovercome these defect of high temperature solid state method, in this paper wesynthesized the precursor of phosphor via chemical coprecipitation and thenthe precursor was sintered in reducing atmosphere for a period of time, coolingin the high temperature furnace, at last the phosphor Sr4Al14O25:Eu,Dy wasprepared.The paper consists of five sections, including introduction, experimental,study of precursor, results and discussion of Sr4Al14O25:Eu,Dy phosphor andconclusions.After discussing the effect of PH value and ageing time on the phasecomposition of the precursor, we determined the optimal technologicalconditions. The PH value of system should be 10 and the ageing time shouldbe 24 hours. Under these conditions, the precursor synthesized was SrCO3 andNH4AlO(OH)HCO3. In the paper we investigated the sorts of factors whicheffect the phase composition and the luminescent performance ofSr4Al14O25:Eu,Dy phosphor with long afterglow, such as the mole ratio ofSr/Al, sintering temperature, sintering time, the quantity of H3BO3 andactivator. The interrelated conclusion in this paper is come to as follows.The phase of phosphors change from Sr3Al2O6 、SrAl2O4 、Sr4Al14O25 、SrAl12O19 with varying the mole ratio of Sr(NO3)2/AlCl3·6H2O from 1/0.6 to1/4.4.The phase of phosphor is Sr4Al14O25 without any other crystalline phaseswhen the mole ratio is 1/3.2.We synthesized phosphors at different temperature and analyzed theirX-ray diffraction patterns and excitation spectrum and emission spectrum. Theresults show that the optimal sintering temperature is1200℃ to synthesizeSr4Al14O25:Eu,Dy phosphor which has the highest luminescent intensitywithout any other crystal phase. During the sintering, the optimal sinteringtime is 3 hours. On this condition, the luminescent properties of the phosphorare best, being Sr4Al14O25 crystal phase, having the highest luminescentintensity. As are indicated by the X-ray http://www.999magnet.com/ diffraction patterns and emissionspectra.The role of H3BO3 addition on the phosphors has been investigated.H3BO3 acts as solvent and with increasing the concentrations of H3BO3, thecrystalline phase and luminescent properties of phosphors are changed. Whenthe concentration is 46%, the phosphor belongs to Sr4Al14O25 crystallinephase with the highest luminescent intensity, according to X-ray diffractionand emission spectra results.
　　The effect of Eu2+ concentration on the luminescent properties ofSr4Al14O25:Eu,Dy was discussed by changing the mole ratio of Eu2+ / Sr2+. Theresults show the relative intensity of tow emission peaks in the emissionspectrum transfers when the mole ratio of Eu2+ / Sr2+ changes. When the moleratio is less than 0.008, two emission peaks exist in the emission spectrum, oneat about 410nm, the other at about 490nm. With increasing the mole ratio, theformer lowers and the latter heighten. The two main emission peaks ofSr4Al14O25:Eu,Dy belong to two luminescent center respectively, which areEu1 and Eu2. They both have a concentration quench process,in which theemission intensity increase first, and then weaken. The critical concentrationof Eu1 is at Eu2+/Sr2+= 0.006/1, and Eu2 at Eu2+/Sr2+=0.012/1. Dy3+ was addedas auxiliary activator, which improved the luminescent properties of phosphors.With the increasing of Dy3+ concentration appropriately, the initial luminescentintensity of phosphor will descend. After the excited light source was removed,the phosphors with high concentration Dy3+ have high luminescence intensityand long afterglow time.Sr4Al14O25:Eu2+,Dy3+ phosphors with long afterglow were synthesizedsuccessfully via chemical coprecipitation method. The sintering temperaturewas lower than that of solid state method obviously and the sintering time wasshortened greatly. http://www.999magnet.com/ The phosphor with small size particle, homogenousgranularity can be applied in many fields. The luminescent properties do notdescend obviously after grinding because grinding can hardly destroy thelattice structure. So it is a kind of soft chemical preparation method withenormous prospects to prepare phosphors with long afterglow via chemicalcoprecipitation method. This method can be easily applied in commercial run,but the initial brightness of phosphor synthesized by this method is lower thanthat by solid state method, which needs being studied further.

添加稀土元素和二氧化硅颗粒的锌铁镀层的腐蚀电化学研究

添加稀土元素和二氧化硅颗粒的锌铁镀层的腐蚀电化学研究
　　In this paper, metal corrosion was narrated, and thermodynamics criterion of metal corrosion was introduced. Besides, electrochemical methods of metal corrosion were stated. Basing on reading mass of datum, electrochemical conosion behavior of five types of ZnFe coating was tested by experiments. Corrosion resistances of five types of coatings were compared, and corrosion mechanisms were preliminarily approached.Tafel polarization curve, Weak polarization curve and Electrochemical impedance spectroscopy (EIS) were adopted to test the corrosion action of the five coatings in quality concentrate 5%NaCl solution as well as volume concentrate 5% H2SO4 medium. The corresponding curves were painted, and the electrochemical parameters of the curves were fitted out. Matching with t3he soaking corrosion, mass change-time graphs were painted, which were about the five coatings and central metals soaking in quality concentrate 5% NaCl solution. Special shape NdFeB magnets Corrosion resistances of five types of Zn Fe coatings were compared through the results of the soaking experiment and soaking experiment and electrochemical method. The influence of the compositions, which were contained in coatings, was tentatively explored.The results of the test indicated: in the coating, Zn and Fe corroded first, which was in accord with thermodynamics criterion and electrochemical corrosion criterion.
　　Observing the surface, we can see: the surface of Zn coating was rough and unsmooth;the surface of Zn-Fe coating was fine and close;and the Zn-Fe-Re coating, as well as Zn-Fe-SiO2 are quite neat and smooth. Contrasting with the soaking experiment and electrochemical method, we can conclude: Five coating materials, Zn/Fe、 Zn—Fe/Fe、 Zn—Fe—Re/Fe、 Zn—Fe—Re/Cu、 Zn—Fe—SiO2/Fe, are chosen to do the test. Tafel plot, also weak polarization curve and Electrochemical impedance spectroscopy have been carried out at 25 °C With the five coatings soaking in the five pieces of 5% NaCl solution as well as 5% H2SO4, Different curves have been printed.. Then we can figure out the relative electrochemical parameters. In contrast to the consequence of the soaking experiment, corrosion resistance has been compared and corrosion mechanism has been approached.Among the five materials, the corrosion resistance of Zn-Fe-SiO2 coating is the best not http://www.999magnet.com/ only in salt solution but also in acid agent, because of putting in the SiO2 particle,which can make the crystalline grain tiny and lower the polarization current, also make the surface smooth. When coating is eroded in medium, SiC>2 particle will form corrosion-products with metal that can decrease the corrosion rate. The corrosion resistance of Zn—Fe—Re/Cu is lower than Zn-Fe-SiO2/Fe in two kinds of corrosion medium, but better than others. The corrosion resistance of Zn—Fe—Re/Fe is good in salt solution, but in acid medium the corrosion resistance is commonly. Zn—Fe—Re composite coating has the finest crystal and uniform surface. When the material is eroded, the corrosion-products can adhere to the surface of coating and decrease the corrosion rate. The corrosion resistance of Zn-Fe/Fe is commonly in both of medium, and corrosion resistance of Zn/Fe is worse than other four materials. Zn-Fe coating is finer and smoother than Zn coating. Zn coating can be passive when it is eroded, but the performance of protection is not satisfactory. This thesis could provide some reference for the improvement of the Zn-Fe electrode position technology.

Chronology and Geochemistry of Jingshan "Migmatitic" Granite in Bengbu

Chronology and Geochemistry of Jingshan "Migmatitic" Granite in Bengbu
　　The relationship between origin of granite and evolution of continental crusthas been one of the issues in the field of earth sciences. The Bengbu uplift islocated in the southeastern edge of the North China craton (NCC), with theTan-Lu fault zone and Sulu orogenic belts as its eastern margin and adjacent toDabie orogenic belt in the south. Chronology and petrogenesis of granites inBengbu uplift, and their relationship with the formation and evolution ofDabie-Sulu orogenic belts have been controversial. However, it is of greatsignificance for us to solve above-mentioned problems not only to understandthe regional tectonic evolution, but also to reveal the effects of Dabie-Segment neodymium magnets Suluorogenic belts on adjacent areas. Therefore, the thesis takes the Jingshan granitein Bengbu as a example, reports its chronology, mineralogy, petrology andgeochemistry, as well as Hf isotope of zircons, and discusses the nature ofmagma sources and its tectonic background.1. Chronology of Jingshan graniteZircon U-Pb isotopic chronology was determined for Jingshan granitesusing SHRIMP method. The dating results for magmatic zircons with oscillatoryzoning rims indicate that they range from 158 to164Ma on the concordia, andyield a mean 206Pb/238U age of 160.2±1.3 Ma, suggesting the Jingshan graniteformed in early stage of the Late Jurassic.2.
　　Geochemistry of Jingshan granite and Hf isotope of zirconJingshan granite shows similar geochemical characteristics with the lategranitic veins, i.e. SiO2 contents ranging from 72.82 wt % to 75.07 wt %,K2O/Na2O ratios being between 0.75 and 0.98, Al2O3 contents and A/CNKvalues ranging from 13.88% to 15.05% and from 0.96 to 1.06, respectively. Theybelong to sub-aluminous to weak peraluminous series. In the Harker diagram, itcan be seen that the contents of Al2O3, Fe2O3, FeO, MgO and CaO decreaselinearly following the increase of SiO2 contents, showing a trend of fractionalcrystallization.Jingshan granites have low ∑REE abundances, ranging from 23.16μg/g to45.41μg/g, average being 31.58 μg/g, and are characterized by relativeenrichment in light rare earth elements (LREE), and depletion in heavy rare earthelements (HREE), and obvious positive Eu anomalies (1.23~2.54). TheirLREE/HREE ratios and (La/Yb)N values range from 1.33 to 11.57 and from 0.71to 10.17, respectively.Chondrite-normalized REE distribution patterns of Jingshan granites show“U” type in shape, which is similar to the high-degree fractionation granites. Therelative HREE enrichment can be related to the existence of garnet and zircon.In addition, Jingshan granites are enriched in large ion lithophile elements(LILE) such as Rb, Ba, and Sr, and depleted in high field strength elements(HFSE) such as Zr, Hf, Nb and Ta. Ba, U, Sr, Eu and Y elements for the graniteshow Segment neodymium magnets obvious positive anomalies in the spider diagram. In contrast, Th, Nd, andSm elements display obvious negative anomalies in the spider diagram.Jingshan granites have high initial 87Sr/86Sr ratios (ISr) (0.7082 ~ 0.7090)and low εNd(t) values (-15.30 ~ -16.20), corresponding Nd model ages (TDM) of2.47 ~ 2.94Ga. They have relatively average Pb isotopic compositions, i.e.,206Pb/204Pb ratios ranging from 17.030 to 17.095, 207Pb/204Pb ratios ranging from15.404 to 15.443, and 208Pb/204Pb ratios ranging from 37.399 to 37.535.The inherited cores and magmatic zircon rims with oscillatory zoning havesimilar initial 176Hf/177Hf ratios, ranging from 0.282060 to 0.282252 andfrom0.282158 to 0.282258, respectively. Inherited cores show relatively low εHf(t)values (-0.71 ~ -7.33), corresponding Hf model ages is 1.44~1.70Ga.
　　Comparedwith inherited cores, the magmatic zircons have lower εHf(t) values (-15.05~-18.39), being similar to the granite, corresponding Hf model age being1.51~1.64Ga.3. Petrogenesis of Jingshan graniteThe field relationship, petrography, the magmatic zircon rims withoscillatory zoning and geochemical data for the Jingshan granite indicate that itshould be derived from the crystallization of granitic magma. Jingshan granitesare characterized by low SiO2 content (<76%), low K2O/Na2O ratios (<1.0), andlow A/CNK values (<1.1), suggesting it belongs to weak peraluminous rocks.Most of the (La/Yb)N values are <5, and Eu/Eu* ratios >0.7. The above lines ofevidence, combined with the presence of epidote, garnet and sphene, and theabsence of cordierite together, suggests that the Jingshan granite is ofcharacteristic of “I” type granite.4. Magma source and its nature of Jingshan graniteSr, Nd and Pb isotopic compositions of granite, Hf isotope of zircons andthe SHRIMP U-Pb dating results indicate that Jingshan granites have affinitieswith the Yangtze craton basement. The primary magma for the granite should bederived from the partial melting of lower continental crust of the Yangtze craton.5. Tectonic setting of formation for Jingshan graniteThe Bengbu uplift is located in southeastern margin of the North Chinacraton (NCC), i.e., belonging to the NCC. The geochemical data for the granitehave indicated that the magma source for the granite should be the Yangtzecraton basement, implying that the Yangtze craton basement could exist withindeep crust of the NCC. It is consistent with the tectonic features that Yangtzecraton subducted beneath the NCC in north-west direction.Combined with the inherited Segment neodymium magnets zircon chronology on the Mesozoic granites ineastern NCC, the discovery of eclogites xenoliths in the Mesozoic adakitic rocksfrom the Xu-Huai area the direction of the Xu-Huai nappe, and geochemicalfeatures on the Mesozoic high-Mg diorites and Fangcheng -Feixian basalts inwestern Shandong together, it is suggested that the collision of the Yangtzecraton with the NCC could take place along the Tan-Lu fault zone in NW or nearW-E direction.It can be concluded that the Jingshan granites in Bengbu uplift could formunder the extensional environment after the rapid exhumation of the Dabie-Suluorogenic belt based on petrogenetic type and petro-geochemical characteristicsof the granite, as well as the analysis for regional tectonic history, which can alsobe demonstrated by the simultaneous volcanic rocks formed under riftenvironment.

北京燕山地区中生代棋盘岩岩体特征及成因

北京燕山地区中生代棋盘岩岩体特征及成因
　　The Qipanyan pluton locates in Jiangshuihe village-Qipanyan village,Mentougou area, Beijing, which has a irregular ellipse in plane shape, extension ofnorthwest and trend of northeast. According to the characteristics of outcrop,mineralogy and petrology, the Qipanyan pluton mainly consist of gabbro,olivine-gabbro, (migmatized) gabbro-diorite and monzodiorite. The SHRIMP zirconU-Pb age of the Qipanyan pluton is early Cretaceous. It is the most mafic Neodymium Magnets pluton inthe Yanshan orogenic belt. So it is the best pluton to study property of mantle magmasource.The Qipanyan pluton is mainly a tholeiite series, so the pluton formed in aenvironment of not very high pressure.
　　The LREE and HREE have an obviousfractionation, in which LREE is enriched and HREE is depleted. According to theSHRIMP zircon U-Pb age study of gabbro in the Qipanyan pluton, it has a age of132.90±0.66Ma. The average initial value of 87Sr /86Sr for the gabro is 0.7045, εNd=-16.54,these characteristics indicate that the source of Qipanyan pluton has adifferent characteristics with EM1 source. Olivine-gabbro has a positive Nbabnormity and a negative Pb abnormity. Rb、Th、Nb、La、U are also have bigdifference with EM1. So we thought the source of olivine-gabbro in Qipanyan plutonis not enriched mantle, but depleted mantle or primitive mantle. The gabbro inQipanyan pluton has a Nb/U=26.4 which is close to the primitive mantle (Nb/U=30). So we concluded that the source of gabbro in Qipanyan pluton is primitivemantle.The thinning mechanism and processes of lithospheric thinning of MesozoicNorth China Craton is the hot spot in the world. There are two http://www.999magnet.com/ models at present: (1)Thermal erosion and/or chemical metasomatism change the lower part of lithospheremantle into asthenosphere. (2) The break off of lithosphere mantle or whlolelithosphere mantle including lowermost part of crust together.According to the study of the Qipanyan pluton, we conclude that the source ofmagma is not enriched mantle (EMI), but asthenosphere mantle. This conclusion isnot consistent with thermal erosion and/or chemical metasomatism mechanismwhich thin lithosphere mantle by changing lithosphere mantle to EM1.So we conclude that the main mechanism for thinning of lithosphere in easternChina is breakoff of lithosphere.

Microstructure and Properties of Mg-Y-Nd-xGd Magnesium-Rare Earth Alloys

Microstructure and Properties of Mg-Y-Nd-xGd Magnesium-Rare Earth Alloys
　　Magnesium alloys, as the lightest structural material in practical application, has achieved rapid development since coming out, attributing to its low density, high specific strength and specific rigidity, excellent damping capacity and electromagnetic shielding capacity, as well as recuperability. However, magnesium alloys are limited to be used at elevated temperature due to its poor heat-resistant ability. WE system magnesium alloys were reported to neodymium magnets be the best candidate in practical use till now. Thus, it’s of great significance to research and develop a new heat-resistant magnesium alloy, serving for high technology industry.In this dissertation, a new magnesium alloy system Mg-5Y-3Nd-xGd-0.5Zr(x=04) is achieved by adding Gd element on the basis of WE54. Samples are melted in electric resistance furnace and poured into steel mould, then heat treated by solution and aging treatment.It is shown that precipitates in the as-cast alloys are mainly composed of bone-like Mg12Nd and massive Mg5Gd, segregated around the grain boundary as discontinuous eutectic structure. Most of Y dissolved into Mg matrix. Spherioidization of grains occurs during heat treatment, and much finer precipitates distribute homogeneously inside the grains and around the boundaries.
　　Then the magnesium-matrix solid solution reaches saturation, and the mechanical properties of the alloys are increased by both solution strengthening and precipitation strengthening of the second phases.The mechanical properties of alloys such as hardness and tensile strength improved significantly after T6 treatment. The max Brinell hardness increases from 71 to 95, with Vickers-hardness from 95 to 129. The max ultimate tensile strength(UTS) and yield tensile strength(YTS) at room temperature are 290MPa and 190MPa, respectively, with little change when heated to 250℃, and can still reach up to 220MPa and 180MPa at 300℃, indicating that it is an http://www.chinamagnets.biz/ excellent candidate for heat-resistant magnesium alloys.By DSC and TEM analysis, the plate-like rhombus metastable phaseβ1, coherent with matrix, is found in the alloy after heat treatment, justifying the aging process should beа→β"→β’→β1→β. Meanwhile, many Zr-rich cores are identified under SEM observation, indicating that Zr can refine grains as heterogeneous crystal nucleus.The deformation mechanism of magnesium alloys alters as temperature increases. At room temperature, it is controlled by dislocation gliding, while at elevated temperature, the sliding of grain boundaries dominates as the atoms can migrate much easier. As to alloys after T6 treatment, its plasticity decreases, and fracture mechanism changes from mix fracture of intergranular fracture and cleavage fracture to quasi-cleavage fracture with increase of Gd. The little addition of Gd can improve the strength as well as plasticity of based-alloy, having great strengthening effect.

Research on Hydrogenation-Disproportionati on Mechanism and Microstructure Study of Nd14Fe66.9B7Co11Zr0.1Ga1.0 at Room Temperture

Research on Hydrogenation-Disproportionati on Mechanism and Microstructure Study of Nd14Fe66.9B7Co11Zr0.1Ga1.0 at Room Temperture
　　This paper based on mechanical milling–HDDR processing, a new technique proposed by our group, to obtain high magnetic properties through addition of Co,Zr and Ga. Hydrogenation-disproportionation of Nd-Fe-B-Ga-Co-Zr alloy by mechanical milling in hydrogen and disproportion knetics were investigated systematically. Desorption-recombination at selected temperature in vacuum and magnetic properties were investigated simplely.Microstructure changes of annealing Nd14Fe66.9B7Co11Zr0.1Ga1.0 alloy were characterized by SEM and EDS analysis. Special shape NdFeB magnets The results showed thatα-Fe in as-cast were eliminated. Microstructural changes of annealing Nd14Fe66.9B7Co11Zr0.1Ga1.0 alloy during mechanical milling in hydrogen were characterized by XRD and TEM analysis. The results showed that Nd14Fe66.9B7Co11Zr0.1Ga1.0 alloy can be disproportionate into Nd2H5,Fe(Co)B andα-Fe(Co) after 20 hours, and the size of the annealing disproportionated phases is about 8 nm after full disproportionation.
　　Disproportionated phases and relative content were characterized by M?ssbauer during different milling time. The results showed that Nd2H5 is about 2.6%, Fe(Co)B is about 16.5% andα-Fe(Co) is about 80.9%. The morphology of the powders millied in hydrogen was characterized by SEM. It was found that the particle size of the NdFeBCoZrGa alloy powders decreased obviously during milling in hydrogen and the size of particle after full disproportionated is about 600nm.Disproportionation kinetics equation was founded. That rotate velocity of milling and ball to powder ratio influence on capability of disproportionation kinetics were studied systematically. The results http://www.999magnet.com/
 showed the higher of intensity milling the faster of disproportionation velocity, and full disproportionation required less time. At the same rotate velocity of milling, large ball to powder ratio milling required less time to accomplish full disproportionation; at the same ball to powder ratio, high rotate velocity of milling required less time to accomplish full disproportionation.With the help of XRD, the desorption-recombination behaviour of annealing disproportionated NdFeBCoZrGa alloy powders was investigated simply. The results showed that nanocrystalline magnetic material with average grain size of about 23nm was obtained by desorption-recombination processing at 760℃for 30 min. The result showed that Br=0.74T and iHc=624.5KA/m and (BH)m=125KJ/m3.

U-Pb Zircon Geochronology, Geochemical and Sr-Nd-Pb Isotopic Compositions of the Hualong Group in Qilian Mountains: Constraints on Tectonic Evolution of Crustal Basement

U-Pb Zircon Geochronology, Geochemical and Sr-Nd-Pb Isotopic Compositions of the Hualong Group in Qilian Mountains: Constraints on Tectonic Evolution of Crustal Basement
　　The Qilian Mountains constitutes the western segment of the Central Orogenic System ofChina (Sulu-Dabie-Tongbai-Qinling-Qilian-Kunlun Orogenic Belt). In the middle massif of theQilian Mountains, the Precambrian basement metamorphic series include the Huangyuan Group,the Maxianshan Group, and the Hualong Group and so on. However, the formation time andtectonic affinity of the Qilian Mountains basements are still controversial. This paper carries out astudy of U-Pb dating, geochemical and Sr-Nd-Pb isotopic compositions from the Hualong Groupand foliated granites. The Hualong Group had experienced upper amphibolite faciesmetamorphism, which is the highest grade in the basement metamorphic series of the QilianMountains. The foliated granites intrude into the Hualong Group. In order to do regionalcomparision, U-Pb zircon ages for a paragneiss of the Block neodymium magnet Maxianshan Group in the QilianMountains basement series were also measured.Some conclusions are sumarried as follows:1. Zircons from the paragneiss consist dominantly of detrital magma zircons with roundedor sub-rounded shape. They have 207Pb/206Pb ages mostly ranging from 880 to 900 Ma, with aweighted mean value of 892±8 Ma, which represents the magma crystallization age of itsigneous provenance and can be taken as a lower age limit of the Hualong Group. Magmacrystallization age for the weak-foliated granite is 875±8 Ma, which can be taken as an upperage limit of the Hualong Group. Accordingly, the formation time of the Hualong Group isconstrained to be between 875 and 892 Ma. Similarly, the zircons from the paragneiss of theMaxianshan Group are sub-rounded shapes. All the detrital magma zircon analyses constitute adiscordia with an upper intersect age of 931±19 Ma. Their weighted mean 207Pb/206Pb age is 939±9 Ma, which is in good agreement with the upper intersect age within errors. Therefore, the ageof 939±9 Ma is interpreted as magma crystallization age of igneous provenance. The agedifference of the paragneisses between the Hualong Group and the Maxianshan Group is about40Ma. This indicates that the Neoproterozoic magma events are diachronous. A few zircons fromboth the paragneisses and the weak-foliated granite display old ages of 1000～1700 Ma. 2. The garnet-bearing amphibolites from the Hualong Group have SiO2= 48.12～53.64%,MgO=3.54～5.94%, CaO=7.21～2.59% and K2O/Na2O=0.2～2.96.
　　They have similar REEpatterns with (La/Yb)N=2.59～5.89 and Eu/Eu*=0.73～0.90. Trace element compositions show theenrichment of U, Th and the depletion of Nb, Ta, Sr, and P.They have 87Sr/86Sr ratios (0.710659to 0.731856) and a wide range forεNd(0) (-3.17 to -14.13). Their protolith were basaltic. Thegneisses of the Hualong Group, except for sample HL-16 (SiO2=78.73%, Al2O3=7.55%,K2O+Na2O=1.57%), display SiO2=72.69～74.43%, Al2O3=11.94～13.24%,K2O+Na2O=6.17～8.42%. All the gneiss samples have fractionated REE patterns with(La/Yb)N=4.76～4.85 and Eu/Eu*=0.31～0.56. Generally, they have similar trace elementgeochemical characteristics with the depletion of Nb, Ta, Sr, Ti and P.They have high initial Srisotopic ratios (ISr) (0.72301 to 0.84504) and negativeεNd(t) values (-1.77 to -3.71). The gneissesbelong to paragneiss, which was derived from igneous provenance expect for the sample HL-16.3. The weakly foliated granites display SiO2 =74.31～76.07% and K2O/Na2O=2.28～3.33.They are peraluminous with A/CNK=1.10～1.26 and have similar trace elemental compositions,characterized by the depletion of Nb, Ta, Sr, Ti and P. Except for the sample 0653 displayinglow∑REE abundance and Eu/Eu*=0.78, all samples have fractionated REE patterns with(La/Yb)N=6.88～7.33 and Eu/Eu*=0.23～0.35. They also have high initial Sr isotopic ratios (ISr)(0.71939 to 0.81042) and negativeεNd(t) values (-2.68 to -5.72). Because of the similarity of thegranite and the paragneiss in their http://www.chinamagnets.biz/ geochemical and Sr-Nd-Pb isotopic compositions, the magmaof the foliated granite was possibly derived from partial melting of the paragneiss. Alternativelythe granites and the original rocks of the paragneiss have the similar compositions of sourceinvolving voluminous hydrous pelite.4. The basement of the Qilian Mountains formed in Jinningian period. Two Neoproterozoicmagmatic events of 940～870 Ma and 790～750 Ma occurred in the Qilian Mountains. Both thebasement rocks and granitoids are characterized by high radiogenic Pb isotopic compositions.
　　Allsamples have 206Pb/204Pb>18.6, 207Pb/204Pb>15.6, 208Pb/204Pb>38.4. The basement rocks andgranites from the Hualong Group have mantle-depleted Nd isotopic model ages (TDM) rangingfrom 1.65～2.15 Ga, with a peak at～1.90 Ga. Combined with the published Nd isotopic data (TDMranging mainly from 1.0～2.4 Ga), they show that crustal growth of the Qilian Mountanis mainlyoccurred during the Proterozoic, without significant Archean information. Thus, the formationtime of basement, Neoproterozoic magmatic events, Pb isotopic compositions and TDM values ofthe basement rocks and granites are similar to those of the Yangtze block but distinct from thoseof the North China block, indicating that the crustal basement of the Qilian Mountains has anaffinity with the Yangtze block.5. The weakly foliated granites are S-type granites, and their petrogenesis was linked tocontinent-continent collision. The abundant detrital magmatic zircons from the Hualong Groupreveal that the provenance of the Hualong Group was dominantly derived from an erodedigneous province. The age difference between the Hualong Group provenance (892±8 Ma) andthe intruded granite (875±8 Ma) is less than 17 Ma. Considering the measurement errors, thebiggest age difference is not over 33 Ma. This http://www.chinamagnets.biz/ indicates that the time-span from erosion of the Hualong Group provenance to transport, then to sedimentation is within 33 Ma, suggesting arapid uplift-erosion process for the Hualong Group provenance and implying an outstandingNeoproterozoic orogenesis in the Qilian Mountains. Moreover, the detrital magmatic zircon agesof 892±8 Ma from the Hualong Group and 939±9 Ma from the Maxianshan Group are close to9～10 Ga tectono-magmatic events obtained from the Qilian, Tarim, Qinling, Qaidam,Oulongbuluke and Longshoushan blocks, suggesting that these west China blocks shared theconvergence of the Rodinia super-continent.

Study on Organic Near-infrared Light-emitting Devices Based on Phthalocyanines

Study on Organic Near-infrared Light-emitting Devices Based on Phthalocyanines
　　Nowadays,the technique of informations displays is the most important means for mankind obtaining information and the technique of organic light-emitting displays attract wide attention as an important member of Flat Panel Displays..In addition ,near-infrared region are widely used in some areas such as the optical communication ,data storage and infrared detection. Nowdays ,the semiconductor lasers based on inorganic material such as third and fifth Ball Neodymium Magnets group compound play an important part in the optical communication. As is known to all, many of these compounds have some toxicity and the fabrication technology of traditionary semiconductor laser is very difficult and the equipments are also dear and the requirement for the purity of the materials is very high.Organic compounds have many excellences such as the easy fabrication technology ,the cheap cost and being able to bend,so many scientists pay importat attention to the organic compounds. Because the main windows of optical communication which lie in 850 nm, 1330 nm, 1550 nm are in near-infrared region. Therefore, to develop low cost and no pollutig organic materials with near-infrared light emitting has potential value for regions like optical communication.Recently most of the organic electroluminescence (EL) materials in the NIR region reported were organic complexes with trivalent rare earth ions such as Er3+, Nd3+, Pr3+, Tm3+,Yb3+. Only few organic materials containing no rare earth ions showed EL characteristic at wavelengths longer than 1μm.But complexes with rare earth ions have some disadvantages.
　　The EL originate from the f-f transition of rare earth ions which is a parity-forbidden process. In addition,the organic light emitting diodes have very low EL efficiency ,because the bandgap of organic ligands is normally large which result in the low effective injection of carriers into organic ligands .To develop organic materials containing no rare earth ions is very important to near-infrared light emitting. Phthalocyanines are the topic which people have studied for about one hundred years..People have synthesized more than 10000 kinds of phthalocyanine derivatives ,which are used in many regions like communication. and so on..Theπconjugated http://www.chinamagnets.biz/ system of phthalocyanines are important in near-infrared light emitting.CuPc is widely used in OLED,which is often used as hole-inject layers.We have fabricated doped and undoped devices with CuPc.First we fabricated undoped devices whose structure is ITO/NPB/CuPc/BCP/Alq3/ Al.There is a weak emitting peak around 1.1μm. Then we develop the structure of the devices and fabricated the alternate devices whose structure isITO/NPB/CuPc/Alq3/....../ CuPc/ Alq3/Al.There is a emitting peak round1.1μm which is stronger than the first one device and this demonstrated the efficiency of energy transfer is enhanced .Then we fabricated the devices employing CuPc doped into CBP. The structure is ITO/NPB/CBP: CuPc/BCP/Alq3 /Al and there is a strong emitting peak round 1.1μm .We change the concentration of CuPc doped into CBP and fabricated devices with different concentration (0 wt% 6 wt% 12 wt% and 20 wt%).The intensity of emitting peak varied with the change of the concentration . 12wt% is optimal and when the concentration is increased,the intensity would be weaker. In the UV-Visible EL spectrum of devices,there is a blue emitting peak which come from NPB. With the concentration of CuPc is increased,the intensity of blue emitting light would be weaker.
　　In the figure of current-voltage characteristics, In the case of lower doping concentrations (≤12 wt %) the driving voltages of doped devices were higher than that of undoped devices. When the doping concentrations were higher than 12 wt% direct hole injection from NPB into CuPc and direct electron injection from BCP into CuPc may lead to the lower driving voltage.These demonstrated that the direct charge trapping process is important and Forster and Dexter energy transfer play a minor role in whole process. This kind of devices are important to near-infrared light emitting diodes. In order to study the effect on the emitting wavelength of phthalocyanines and on the intensity of emitting peak,we have synthesized substituted phthalocyanines according to the molecule structure of CuPc and H2Pc,i.e. (4-thymol)CuPc and(4-tert)H2Pc.We purified the materials.Then we tested PL spectrum of (4-thymol)CuPc under 300K. The films of (4-thymol)CuPc were deposited in vacuum .There was only a emitting peak round 1150 nm.We fabricated devices employing (4-thymol)CuPc whose structure is ITO/NPB/ (4-thymol)CuPc /Alq3 /Al .There is a emitting peak round 1.1 urn whose position is near that of the devises based on common CuPc.Then we fabricated the organic light http://www.chinamagnets.biz/ emitting devices based on (4-tert)H2Pc doped into CBP,whose structure is ITO/NPB/CBP:(4-tert)H2Pc/BCP/Alq3/Al. We fabricated devices with different concentration(20 wt%, 40 wt% 80 wt% and 100 wt%).Throughtesting the near-infrared spectrum,we found there was a emitting peak round 910 nm for the devices,the intensity of emitting peak decreased with the increase of the concentration.In addition,we have synthesized novel three-nuclear PcZn.Bu we fail to purify the materials,so there is 2,3-tetra-(2-iPr-5-Me)PcZn in the materials.We spin cost the mixture of PVK and the materials on quartz slice and through testing ,we found there was a strong emitting peak round 900 nm .Then we fabricated the devices employing the materials.We tested the near-infrared characteritcs,and found the emitting peak lied round 900 nm ,which is compatible with PL spectrum.but we can not confirm which material is relate to the peak and this requires the further study.

400-500MPa耐大气腐蚀钢工艺及性能研究

400-500MPa耐大气腐蚀钢工艺及性能研究
　　Weathering steel is made by alloying with certain elements which is one kind of low alloy high strength steel with good corrosion resistance. It is widely used in steel structures such as train cars, bridges and buildings. As a high effective steel product, It has been being the focus of development of products and corrosion research. The new generation weathering steels should meet the development requirement of higher-speed and heavier-load of railway Ball Neodymium Magnets transportation in our country. Therefore, the properties such as high strength, high toughness, high ductility, low yield ratio, low toughness-brittleness transformation temperature (TTT), obvious yield point, good weldability and corrosion resistance should be included in the development target to meet the requirement of manufacture, loading capacity and safety during uninterrupted movement of train cars.The article is dealing with such topics as how to ensure atmospheric corrosion resistance, to realize high strength and further improve toughness and ductility, as well as to improve weldability. Correspond measures are put forward by detail analysis. Optical microstructure, mechanical properties, toughness-brittleness transformation temperature, aging-resistance, weldability, corrosion resistance were investigated. The results show that the designed chemical compositions and process of the Pangang-developed 400Mpa, 450Mpa and 500Mpa grade Cu-P-Cr-Ni and rare earth treated Cu-Cr-Ni high strength weathering hot-rolled steel plate for train cars are rational. The results show that the complex properties of experimental steels are good.
　　These steels can be put into stable commercial production.The experimental steels were VN microalloyed and treated with microalloying Ti. The microstructure of V-Ti-N steels is similar to V-Ti steels, consisting of polygonal ferrite and pearlite. The effect of [N] in the steels results in on one hand, more precipitated vanadium and on the other hand, http://www.chinamagnets.biz/ makes the precipitates of vanadium finer and denser. Therefore, more dense and fine precipitates can be found in V-Ti-N steels than in V-Ti steels. The precipitated vanadium can also be affected obviously by the Ti content in steels. However, The precipitated vanadium increases with [N*] content in steels. It is very important for thestability of strength and the enhancement of strength of V-Ti-N steels to suitably lower the Ti content in steels and stably control it. The experimental steels exhibit lower toughness-brittleness transformation temperature and the aging caused by free nitrogen can be neglected because the enhancement of nitrogen results in more precipitates of vanadium and the free nitrogen content in steels is kept at lower level. It also shows that little Ti adding in steels with lower Mn content and adjustment of the coiling temperature can elevetate weldability and gain obvious yield point. Forthermore, the better range of RE content is obtained. It is effective for purifying steels, modifing inclusion and enhancing microalloying effect, the direct impact values of steels are improved.The technology stragy of high strength weathering steels at Pangang steel is ascertained through experimental work. The study offers the essential technical surport for the further development of products.

Effects of Modifier-treatment on the Corrosion Resisitance Properties of As-cast Al-5wt.%Cu Alloy in NaCl Solution

Effects of Modifier-treatment on the Corrosion Resisitance Properties of As-cast Al-5wt.%Cu Alloy in NaCl Solution
　　Aluminum alloys as traditional metal materials with lower density, higher specific strength, heat machining capability,are widely used in aerospace, automobile. With the rapid development of modern industry, the need of structures existed stengthen and toughening and light-weight together is urgent. Applications of Aluminum alloys will become more and more wide. As a result, people demand for as-cast Al alloy with more higher mechanical properties. So the high strength and toughness aluminum alloys has its development chance to research and applications. in system of aluminum alloys, Al-Cu alloy turn into hot focus of high tensile strength and ductility aluminum alloys,because of its well mechanical properties. However, Al-Cu alloy as a high tensile strength and ductility aluminum alloy, has poor corrosion resistance.its applications have potential hazard to bring tremendous economy loss and catastrophic accident. So the applications are limited for Block Neodymium magnets intergranular corrosion mainly. when strength and ductility of Al-Cu alloy is researched, its corrosion resistance is investigated at the same time,which have important signification of theory and practice. Al-Cu alloy is researched as a target for its properties, the present study has utilized different modifiers treatment technology to improve the corrosion resistance of the Al-Cu alloy.
　　The efforts on the corrosion resistance of the present alloy with different modifiers technology are also investigated, at the same time, the optimal modifier and its content in the alloy are optimized. The study discussed the corrosion resistance mechanism of the alloy preliminary, which can be achieved depended on analyzing the average weight loss, average loss rate,the corrosive morphology and electrochemistry behavior of the alloys. All above has important signification of theory and practice to make high tensile strength and ductility aluminum alloys with excellent corrosion Block Neodymium magnets resistance.The results showed: the three modifiers used in the experiment improved the corrosion resistance of the alloy in various degrees. It can be judged that: first,the corrosion resistance of the alloy with 0.1wt.% Sc is best, when the alloy is modified by Sc only; secondly, the corrosion resistance of the alloy with 0.4 wt.% Ag is best, when the alloy is modified by Ag only; thirdly, the corrosion resistance http://www.999magnet.com/ of the alloy with 1.5 wt.% PrxOy is best, when the alloy is modified by PrxOy only.
　　By contrasting the corrosion resistance of the above alloys, it can be found that the corrosion resistance of the alloy is improving remarkably when it is modified by 1.5wt.% PrxOy. The average weight loss of the alloy modified by 1.5 wt.% PrxOy decreased 47.53%, and its average loss rate reduced 24% compared with the unmodified alloy. The corrosion resistance property of the alloy is so well enough that there is not report concerning the similar alloy in home and abroad provisionally. Its application in the fields of automotive and aerospace will be wide and nice in the future. Through the measurement of the polarization curves and the corrosion potential, breakdown potential, we can know that the alloys modified showed a stable passivation area after activation-passivation transition area, but it can not be found in the unmodified alloy.The corrosion potentials and the breakdown potentials of the alloys present a trend of increase and then decrease when we add more PrxOy in the alloys. Especially, the corrosion potential of the alloy modified by 1.5wt.% PrxOy whose breakdown potential is -10.658V, is -1.069V. The increasing of the corrosion value indicated the trend of the alloy corrosion is lower, accordingly the higher breakdown potential showed the occurrence of the pitting corrosion is more difficult on the modified alloys’surface. So the corrosion resistance of the alloy is improved. We analysed the electrochemical impedance spectroscopy of the alloys in 3.5wt.% solution and learned that the oxide film on the alloy surface modified by 1.5wt.% PrxOy was relatively integrated, which protected the alloy well; moreover, the high resistance reaction inhibited the formation of the pitting and improved the corrosion resistance of the alloy.Al-Cu alloys had poor corrosion resistance.
　　The intergranular corrosion of the Al-Cu alloys was caused by second-phase precipitation in grain boundaries and precipitate free zone in near area. As different corrosion potentials among precipitate phase, precipitate free zone and grain self; when corrosion medium existed, numberless electrochemistry tiny-batteries came into being, which resulted in channels of anode dissolve over grain boundaries, this was intergranular corrosion. The corrosion resistance of the present Al-Cu alloy improved for the addition of rare-earth oxide obviously. The reasons are: for one thing, the alloy modified by rare-earth oxide, caused the structure more uniform, made the grains smaller, restrained the second-phase particles growing up and gathering, reduced the cracks of the structure, so decreased the corrosion sensitivity greatly. The surface of the alloy produced uniform and stable oxide film fast after the film formed in the air naturally had been destroyed, which can prevent the surface corroding, http://www.999magnet.com/ control the corrosion hole growing up. For another thing, it reduced the grain boundary attenuation, restrained the growing of the PFZ and the second-phases near the boundaty, so the degree of the corrosion would be reduce. There is not obvious anodic corrosion channel, which restrained the corrosion, simultaneously caused the film to be difficult to break and easy to obtain repair. It became difficult that the further expansion and connected to corrosion area of the corrosion holes. All above reduced the grain flaking possibility fundamentally.

Preparation, Application of Multiplex Core-shell Fluorescence Nanoparticles as Bio-labels and Novel Model of Immuno-PCR Mediated Using Phage

Preparation, Application of Multiplex Core-shell Fluorescence Nanoparticles as Bio-labels and Novel Model of Immuno-PCR Mediated Using Phage
　　This dissertation focuses on ultra-high sensitive detection technology. Time-resolved Fluoroimmunoassay (TRFIA) and immuno-PCR are two such tools that are applicable to detection of very low concentration of antigen, antibody and pathogenic microorganism. And this dissertation consists of three parts, including a brief review of ultra-high sensitive detection technology, the synthesis of BBCAP and preparation, application of multiplex core-shell fluorescence nanoparticles; and development of phage-mediated immuno-PCR.In chapter one, the basic principles and highlights of different kinds of ultra-sensitive detection technology are reviewed. The late Special shape NdFeB magnets development in TRFIA and immuno-PCR for protein detection are summarized. And finally the research proposal for this dissertation is presented.In chapter two, we first describe the synthesis of a new lanthanide chelate: 2,9-bis[N,N-bis(carboxymethyl)aminomethyl]-1,10-phenanthroline (BBCAP) could bind both Eu(III) and Tb(III) and display their respective fluorescent. BBCAP was covalently linked with 3-aminopropyl(triethoxy) silane to form silica nanoparticles in the presence of precisely controlled ratios of Eu(III) to Tb(III). The nanoparticles thus prepared could have specified ratios of luminescence intensities at two well-resolved emission under a single-wavelength excitation. After comprehensive characterization with respect to their fluorescence lifetime, photostability, thermostability, and chelate leakage, practical use of these nanoparticles was evaluated in a time-resolved immunofluorometric assay of human hepatitis B surface antigen (HBsAg).
　　The detection antibody was labeled with the Tb(III) silica nanoparticles using a site-specific labeling strategy that allows the binding sites of the labeled antibody orient away from the nanoparticles and toward the antigen. The detection limits, calculated with http://www.999magnet.com/ the concentration corresponding to three times of the standard deviations of the background signal, was 35 pg/mL. The upper limit of the calibration curve was ca 200 ng/mL. The coefficient of variation (CV) across the whole range was below 8.9%. In comparison, under the same conditions, the detection limit of ELISA was 200 pg/mL and the upper limit of the calibration curve was ca 10 ng/mL. In chapter three, we described an ultrasensitive immunoassay for detecting HBsAg via immuno-PCR using phage-antibody complex. We chose T7 phage as a natural DNA containing nanoparticle to develop immuno-PCR. The phage was first activated with sulfo-SMCC in sodium phosphate, while antibody was thiolated using Traut’s reagent in a non-amine-containing buffer. The activated phage and the thiolated antibody were mixed immediately, after reaction overnight at 4°C, the mixtures were purified by Pall filter, resulting the phage-antibody complex. Regular PCR tubes were activated using 1% glutaraldehyde, and then coated with antibody. The results showed that there’s a linear range from 1000 ng/mL to 0.01 ng/mL for HBsAg. The detection limit was ca 0.1 pg/mL. HBsAg was examined in sera from Hepatitis B patients and negative control using both immuno-PCR and ELISA, and the results showed immuno-PCR correlated well with ELISA.

Preparation and Luminescence Characteristics of Eu-doped Nanocrystalline Zinc Oxide

Preparation and Luminescence Characteristics of Eu-doped Nanocrystalline Zinc Oxide
　　Luminescence is a process during which the absorbed energy is converted to optical radiation in some way. The photoluminescence is a phenomenon that some objects shine in some certain conditions after absorbing and storing the light energy. The photoluminescence material can be widely used in many fields such as the screen of TV, computer and fluorescent lamps. It also can be used as a material to produce a lot of luminous products such as dope, printing ink, concrete, plastic, paper, ceramic, glass, in dustrial artwork and clock. Therefore photoluminescence material plays an important role in the following fields: archietcture, decoration, transportation, military, light chemical Block neodymium magnet industry, emergency lighting, and anti-forged sign.Although a great progress has been made after about 10 year researches and applications of photoluminescence material, the study evolvement of the red photoluminescence material is quite slow in comparison with the mature manufacture techniques of the green and blue photoluminescence material.
　　The main raw materials of the traditional red photoluminescence materials are the costly rare earth oxides such as Y2O3 and Eu2O3. However, ZnO is adopted as the main raw material in this paper. ZnO is a cheap oxide, which can intensively absorb the ultraviolet light and has the properties of stability in physics and chemistry. The red photoluminescence material http://www.chinamagnets.biz/ used ZnO as the matrix material can be applied to various abominable nature conditions such as cold north, fervent south and tableland with strong ultraviolet radiation. It can be also widely used in the field of the palette of aircraft coating. In this experiment the rare earth element Eu is used as the sensitive components.Direct precipitation, homogeneous precipitation and microemulsion method are adopted to prepare the red photoluminescence material ZnO:Eu3+. The microshape and the structure of crystal can be determined by the X-ray diffraction (XRD) and SEM (scaning electron microscope).The results of the present study are listed as follows:(1) With solution precipitation method by using urea or ammonia as precipitator and microemulsion method by using cetyl trimethyl ammonium bromide(CTAB) as surfactant, the red photoluminescence material ZnO:Eu3+ can be fabricated from two main materials Zn(NO3)2·6H2O and Eu2O3.
　　There are also two main emission peak at 595nm and 612nm in ZnO:Eu3+ samples prepared by precipitation method, furthermore, red-shift phenomenon is found in the sample prepared by the homogeneous precipitation and the most stong peak is http://www.chinamagnets.biz/ at 592nm. In the case of intensity of emission, the sample prepared by direct precipitation is little better than that by homogeneous precipitation. But there is no found 595nm emission peak in the ZnO:Eu3+ sample prepared by the microemulsion method, which has only one emission peak at 615nm and eradiate red luminescence.(2)The crystalline structure of samples from solution precipitation and microemulsion method, is the same as that of pure ZnO, which shows that the most adulterated elements Eu3+ have been mixed into the ZnO crystal lattices. Through the analyse of XRD, the red photoluminescence material ZnO:Eu3+ samples prepared by the microemulsion method contains impurity Eu2O3.(3)The luminous mechanism of samples can be described as follows: Eu3+ mixed into the ZnO crystal lattices forms many centers of luminescence.(4) Through direct precipitation or homogeneous precipitation can prepared ZnO: Eu3+ nano-powders, and varying degrees of reunion phenomenon also exists. The size distribution of ZnO: Eu3+ sample prepared by the direct precipitation method is between the 300nm-1μm, and particles shows column or flake state, otherwise, that prepared by the homogeneous precipitation method is between 100nm-200nm and particles shows short column state. The rod-shaped particles can be fabricated by the microemulsion method, which dispersed well and the distribution of particle size is between 50nm-100nm .(5) The results indicate that the homogeneous precipitation method and the microemulsion method can be regard as better methods for the preparation of the red photoluminescence material ZnO:Eu3+ than the direct precipitation method.

Synthesis and Characterization of a Novel Europium Chelate: BC-EDTA, and Labeling Nanoparticles for TrFIA

Synthesis and Characterization of a Novel Europium Chelate: BC-EDTA, and Labeling Nanoparticles for TrFIA
　　This dissertation focuses on ultra-high sensitive detection technology. Time-resolved Fluorescence Immunoassay(TRFIA) is such a tool that is applicable to detection of very low concentration of antigen,antibody and pathogenic microorganism.Ball Neodymium Magnets And this dissertation consists of three parts,including a brief review of ultra-high sensitive detection technology,the synthesis and characteration of BC-EDTA;preparation,application of time-resolved fluorescence nanoparticlest and their application in TRFIA.In chapter one,the basic principles and highlights of different kinds of ultra-sensitive detection technology are reviewed.
　　The latest development in TRFIA for protein detection are summarized.And finally the research proposal for this dissertation is presented.In chapter two,we first describe the synthesis of a novel lanthanide chelate:2,9- bis [N,N-bis(carboxymethyl)aminomethyl]-4,7-diphenyl-1,10-phenanthroline(BC-EDTA), which could chelate with Eu3+,and display its fluorescent character.We characterize the chelate by ESI-MS,IR,UV and H1NMR,the results show that the chelate we synthesized is completely correct.In chapter three,we covently lebeled BC-EDTA onto the surface of bare silica nanoparticles,and applied them in TRFIA.The bare silica nanoparticles we synthesized using reverse microemulsion method,and the diameter of particles could be optimized by the ratio of TEOS, http://www.chinamagnets.biz/   H2O and amonia.APTMS was added to introduce amino group onto the surface of bare silica nanoparticles.BC-EDTA can be covently labeled onto the surface of amino-nanoparticles using EDC,NHS in PB(pH=6.8). Finally,amino group was introduced onto the surface of fluorescent nanoparticles, such as antibody,antigen and DNA can be linked on to it.We detected hepatitis B surface antigen using the fluorescenct nanoparticles.The detection limits,calculated with the concentration corresponding to three times of the standard deviations of the background signal,was 65 pg/mL.The upper limit of the calibration curve was ca 200 ng/mL.The coefficient of variation(CV) across the whole range was below 20%.In comparison,under the same conditions,the detection limit of ELISA was 200 pg/mL and the upper limit of the calibration curve was ca 10 ng/mL.

Geochemistry and Tectonic Setting of the Volcanic Rocks of Early Permian Dashizhai Formation in Dashizhai Area, Inner Mongolia

Geochemistry and Tectonic Setting of the Volcanic Rocks of Early Permian Dashizhai Formation in Dashizhai Area, Inner Mongolia
　　IntroductionThe early Permian volcanic rocks in the Dashizhai Formation are widely distributed in the middle part of Inner Mongolia. The research of lithologic characteristics and spacial distribution of volcanic rocks is a key to reveal the tectonic setting and late Paleozoic regional tectonic evolution. In the thesis, taking the volcanic rocks of the typical established formation section in the Dashizhai formation as an object of study. Based on the systematic research neodymium magnets of petrology, geochemistry and component charge of regional volcanic rocks, the formation age of the volcanic rocks are determined and the magma sources and its properties are studied. The research also elucidates the tectonic setting of volcanic rocks.1. Spacial and temporal distribution of the volcanic rocks of Dashizhai FormationGeochemical component of the volcanic rocks of Dashizhai formation in Inner Mongolia shows apparent polarity characteristics. According to the component polarity, the volcanic rocks can be divided into south and north zones. The south volcanic zone extends from Mandoula via Linxi to Aluqi area,where the volcanic rocks is mainly composed of low-K tholeiitic series and a small portion of calc-alkaline series. The north volcanic zone extends from Sunitezuoqi–Xiwuqi to Dashizhai area, where calcalkaline series is dominant. The spacial distribution of the Dashizhai volcanic rocks is related with the suturing of Xar Moron river tectonic belt.We think that the age of Dashizhai formation is Artinskian in early Permian according to the evidences of stratigraphy, paleontology, geochronology of regional Permian volcanic rocks and granite, and detrital zircons geochronology of the late Permian stratum of Linxi formation.
　　2. Rock associations and geochemical characteristics of the Dashizhai volcanic rocksThe Dashizhai volcanic rocks are mainly composed of basalt, basaltic andesite, andesite and rhyolite .They have a calc-alkaline evolutionary trend in SiO2 vs. K2O diagram.The contents of SiO2 of basalt, basaltic andesite, andesite are between 47.60%～57.99%, Al2O3 between 16.45%～18.3%. They are characterized by low content of MgO (Mg#=3338),K2O (0.30%～0.99%) and relatively high content of Na2O (1.96%～3.16%) . Negative correlations of SiO2 vs. FeOT、MgO、TiO2、CaO and P2O5, and positive correlations of SiO2 vs. Al3O2、Na2O、and K2O are shown in Harker Diagrams. The rhyolite has SiO2 content of 75.77%～81.06%, Al2O3 of 9.86%～12.91%, and is characterized by lower MgO content, Mg#=15～20, and higher contents of Na2O (3.4%～4.28%) and K2O( 3.44%～5.11%).The total rare earth element contents (ΣREE) of the basalt, basaltic andesite, andesite are between 81.72180.37ppm. Their (La/Yb)N ratios andδEu values range from2.43 to 5.87 and from 0.91 to 1.03, respectively. On the chondrite-normalized REE diagram, the Dashizhai volcanic rocks are characterized by enrichment of LREEs, depletion of HREEs, and minor negative Eu anomalies or no Eu anomalies.
　　On the MORB-normalized spider diagram, all the samples are enriched in large ion lithophile elements (LILEs, e.g., Rb, Ba, Th, and K) and LREEs, depleted of high field strength elements (HFSEs, e.g., Nb, Ta, Ti), which is similar to the volcanic rocks of Andean arc. The total contents of rare earth element (ΣREE) of rhyolite are between 63.02ppm and 121.74ppm. Their (La/Yb)N ratios andδEu values range from 2.45 to 7.73 and from 0.35 to 0.50, respectively. On the chondrite-normalized REE diagram, the rocks are characterized by enrichment of LREEs, depletion of HREEs, and show negative Eu anomalies. On the MORB-normalized spider diagram, all the samples display enrichment of large ion lithophile elements (LILE e.g.,Rb、Ba、K), and LREEs and depletion neodymium magnets  of high field strength elements (HFSEs, e.g., Nb, Ti).3. The nature of magmatic source and the Magmatic evolution characteristics of the Dashizhai volcanic rocksCompared with the geochemical characteristics of the mantle-derived primary magma, the early Permian volcanic rocks in Dashizhai area are not primary magmas, because they are lack of the mantle-derived inclusions, and have low Mg# values(<65) and low contents of Sc (20-32μg.g-1), Co (173533-42μg.g-1) and Ni (88-120μg.g-1).
　　The existence of phenocrysts, such as pyroxene and plagioclase, in the volcanic rocks suggests the magma experiences fractional crystallization of these minerals during evolution, which is also proved by the linear correlations between SiO2 and other major oxides and trace elements.Geochemical characteristics of major elements and trace elements suggest that depletion of HFSEs, such as Nb and Ta, can not be explained by simple residue of minerals, which are enriched in HFSEs in magmatic source, or by contamination of crustal materials. The characteristics of component polarity of the vocanic rocks indicate that the parental magma could be derived from partial melting of the mantle wedge metasomatized by subduction-related fluids. Geochamistry of rhyolite shows that the magma derived from partial melting of the crust.4. The tectonic setting of Dashizhai volcanic rocksThe association and geochemistry characteristics of early Permian volcanic rocks in Dashizhai is similar http://www.chinamagnets.biz/ to those occurred in active continental margins (e.g., Andes), suggesting that they were formed in active continental margin setting.In the M/Y-Nb/Y(M=Zr、Nd、La、Th、Rb、Ba)diagram, by contrast with volcanic rocks in typical tectonic setting, not only the component polarity of the Dashizhai volcanic rocks is showed, but also the tectonic setting of active continental margin setting is reflected.The Subduction of Paleo-Asian Ocean plate is bidirectional in Early Permian. From middle Permian the active continental margin of the Jiamusi-Mongolia block turn to passive continental margin. The North China plate and Jiamusi-Mongolia block sutured along Suolun-Xar Moron river-Changchun in late Permian ultimately.

Study on Preparation of Rutile Crystalline Glaze and Crystallization Mechanism

Study on Preparation of Rutile Crystalline Glaze and Crystallization Mechanism
　　Crystalline glaze is a kind of art glaze with excellent decorative performance. Now, the system of willemite crystalline glaze as the most common crystalline glaze is single. Little theoretical analysis on the crystal growth has been reported. In this paper, TiO2 was introduced into willemite crystalline glaze. The influence of TiO2 addition and processing conditions on the phase constitution and patterns of crystal flowers of the crystalline glaze was studied. Special shape NdFeB magnets Also, the feasibility of using coal gangue as a substitute for clay to prepare crystalline glaze was investigated.The results showed that a rutile crystalline glaze with better aesthetic appearance was prepared under the conditions of melting temperature of 1250℃and crystallization temperature of 1130℃.
　　The crystals in the crystalline glaze could self-grow and overspread the whole surface of the glaze. The amount of the crystals increased with the increase of the crystallization temperatures. XRD and optical microscope results indicated that the precipitated crystals were long columnar rutile crystals. The optimizing raw materials formula for the crystalline glaze was as follows: 14.5%TiO2, 10.1%ZnO, 11.6%flint clay, 63.5%glass frit and 0.3%CuO. This paper also showed that.Rare earth oxides were also introduced into the crystalline gaze as colorant. The results showed that CeO2 could make the crystalline glaze present steady yellowness and Er2O3 could make crystalline glaze present steady redness at high temperature. The addition of rare earth oxides made the long http://www.999magnet.com/ columnar crystals in the crystalline glaze became thinne. The crystal structure did not changed.Using coal gangue as a substitute for clay to prepare crystalline glaze body showed has little effect on the hygroscopic coefficient, the porosity, volume concentration, flexural strength and the bonding between the crystalline glaze and the body. When the rate of the coal gangue reached 46%, the performances mentioned above had little changes. The results indicated that it is completely feasible to use coal gangue as a substitute for clay to prepare crystalline glaze ceramic body.

Study on Electrical and Magnetic Properties of LCMO/SBT Composites

Study on Electrical and Magnetic Properties of LCMO/SBT Composites
　　Manganese pervoskite rare-earth oxides have been the hot topic for recent years, due to the potential application on magnetic storage, and magnetic sensor and so on. The colossal magnetoresistance is the common character of this kind of materials.Manganites are typical strongly correlated electron systems, spin, and charge, and orbital freedom degrees of coupling are crucial to the characters. The classical theories that neglect some interactions on studying the properties of Alnico magnets manganites do not work any more. So to understand the mechanism of CMR in manganites is a main challenge in condensed matter physics.In this paper, we mainly talk about the work done by me as a master during the recent two years.
　　The contents include four sections: firstly introducing the situation about the development of rare earth manganites, secondly telling the samples preparing and measuring methods, thirdly analyzing the results of measurement and summarizing the meaning in application generally, and fourthly describing the mechanism of measurement system designed by ourselves in high temperature region.We prepared the (La0.67Ca0.33MnO3 )1-x/(SrBi2Ta2O9)x (x=0%,1.5%,2%,3%,5%,7%,10%,15%,20%,25%) by conventional solid-state reaction. The electrical and http://www.999magnet.com/ magnetic transport properties were investigated systemically. It is interesting to note that with increasing SrBi2Ta2O9 (SBT) dopant, the change trend of the resistivity is different. When in low dopant, the resistivity increases as the SBT addition. When SBT reaches up to a certain value the resistivity decreases with increasing the dopant contents. However, the trend is not remained and changed as x>25%. The temperature transition of ferromagnetic-paramagnetic shifts to low temperature region and the magnetoresistance (MR) increases with the adding of dopant. But we still assume that MR won’t be keep increasing continually and there must be a maximal value.

Giant Electrocaloric Effect of Oriented Pb(Zr0.95Ti0.05)O3 Ferroelectric Thin Films

Giant Electrocaloric Effect of Oriented Pb(Zr0.95Ti0.05)O3 Ferroelectric Thin Films
　　To remit environment problem, late-model no-Freon (Zr-rich PZT Electro-caloric material) was investigated and prepared. Oriented Pb(Zr0.95Ti0.05)O3 (PZT) thin films with rare earth–La3+ dopants were prepared on Pt/Ti/SiO2/Si substrate by sol-gel technique. Effects of different Thermal treatment methodology on orientation of PZT thin films and different Block neodymium magnet orientation on Electrocaloric of PZT thin films were investigated systematically.Mechanism of oriented growth of Zr-rich PZT thin films was analyzed. Relevant theoretics of oriented growth of Zr-rich PZT thin films was put forward. Different anneal technics and cycstallographic texture of Zr-rich PZT thin films were compared. (100)-oriented Zr-rich PZT thin films was gained by anneal at 650℃for 5min, and (100)-oriented Zr-rich PZT thin films was gained by anneal at 600℃for 3min.
　　Otherwise along with increase of pyrolyzing temperature, (100)-orientation of Zr-rich PZT thin films increase and peaked at 425℃.Based on the analysis of SEM and AFM, an obvious difference in crystallization of PZT thin films with La doping was observed. There was no obvious diffusion and the combine between Pt electrode and PZT thin films and grains with small size and uniform distribution are shown in PZT with 0.5 mol% La3+ dopant. More La3+ dopant was, more large grain was and small degree of coarseness was.Electrocaloric effects of different oriented PZT and PLZT thin films were investigated systematically. It was shown that Electrocaloric of http://www.chinamagnets.biz/ Oriented Zr-rich PZT thin films excelled polycrystalline PZT thin films. max of ElectrocaloricΔT of Oriented Zr-rich PZT thin films was 29K, while max of ElectrocaloricΔT of polycrystalline Zr-rich PZT thin films was 12K. It was also shown that electrocaloric of (111)-oriented Zr-rich PLZT thin films excelled (100)-oriented Zr-rich PZT thin films. La dopant enhanced Electrocaloric of Zr-rich PZT thin films. Rare earth Yb mainly occupied A-site in PZT lattice, the rank of long-range order of ferroelectric structure. Thereby stabilization of ferroelectric structure was restrained, because substitution of La3+ was the no-equivalence electric charge substitution, charge balance of cycstallographic texture was destroied and stabilization of antiferroelectric structure. All of these were prone to increase dispersion of electric field and enforce electrocaloric effects of Zr-rich PZT thin films.

Preparation and Fischer-Tropsch Estimation of Bridging Complexes of Cobalt Cluster and Lanthanide

Preparation and Fischer-Tropsch Estimation of Bridging Complexes of Cobalt Cluster and Lanthanide
　　In this paper, bridging complexes, which can be used as the precursor of F-T synthesis, contain both cobalt carbonyl cluster and lanthanide were designed to use as the precursor of F-T synthesis reation. First, Tetrahedron-cobalt carbonyl cluster with carboxyl was synthesized use Co2(CO)8 as the raw material, the cluster was used to react with lanthanide (La, Ce, Sm and Yb) trifluoroacetate to construct bridging complexes. Then, a series of catalysts were prepared by strong magnets impregnating the complexes synthesized above onγ-Al2O3 support for the first time, and F-T catalytic performance was evaluated.
　　Concrete work as follows:1. Cluster (CO)9Co3 [μ3-CC6H4(CH2)2COOH] was used to react with lanthanide (La, Ce, Sm and Yb) trifluoroacetate respectively, and a series of bridging complexes contain lanthanide and cobalt cluster were synthesized and characterized by IR,ICP,C/H element analysis and thermal analysis, after comparing the bridging complexes with a similar structure complex that has already been synthesized in our lab,the structure of the complexes were speculated as: two lanthanide atom were bridged by four CF3COO-, cobalt carbonyl cluster and THF were coordinated to the lanthanide atom to form a steady structure. Since these complexes’ crystallization http://www.chinamagnets.biz/ condition difficult to control, crystal training work remains to be further explored.2. A series of catalysts were prepared by impregnating the complexes synthesized onγ-Al2O3 support, and characterized by surface area analysis (BET), and thermal analysis (TGA). The catalytic performance for F-T synthesis was tested, following are results:Using complexes precursors such as the cobalt carbonyl cluster and lanthanide bridging complexes resulted in a significant increase of cobalt dispersion in comparison with catalyst in the reference made from cobalt nitrate, but less activity.

The Study on the Synthesis and Properties of Rare-earth Oxide Red Long-lasting Phosphor

The Study on the Synthesis and Properties of Rare-earth Oxide Red Long-lasting Phosphor
　　Combustion method and hydrothermal method are used to synthesize preferable Eu3+-activated yttrium oxide long afterglow phosphor. And the two methods are compared.Rare long afterglow was observed in the Y2O3:Eu3+, Ca2+, Ti4+ and the duration can nearly 1h by Combustion method. The maximum emission wavelength is at 609 nm. XRD display a Ball Neodymium Magnets cubic structure of the Y2O3. The Experimental Propertied the long afterglow phosphor Y2O3:Eu3+, M2+, Ti4+ doped different radius Mg, Ca, Sr, Ba, Zn. Ba2+and Sr2+ have The same trend of decay and have the fastest decay.
　　The trend of decay is in the order ofМg2+,Zn2+,Ca2+ form low to high. The Smaller the radius of the ion the easier it is to enter the lattice formed in the appropriate depth of the trap. The Experimental inspected the impact when the Al, Gd ware doping at the afterglow of products. The Experimental found Gd access to growth afterglow time and enhance luminous and Al did not access to growth afterglow time and enhance luminescence.Rare long afterglow was observed in the Y2O3:Eu3+, Mg2+,Ti4+ and the duration can nearly 1h by hydrothermal method. The maximum emission wavelength is at 609 nm. XRD display a cubic structure of the Y2O3 .XRD and TEM show that crystallization of the precursor is conducive to better luminous materials. The Experimental inspected the impact when the Al, Gd ware doping at the afterglow of products. The Experimental found Gd access to growth http://www.chinamagnets.biz/ afterglow time and enhance luminous.Combustion method and hydrothermal method are used to synthesize Y2O3:Eu0.030, Mg0.020, Ti0.030. The two methods are compared that the latter decay slowly and have long afterglow and low luminous intensity.

Synthesis, Characterization and Applications of Phosphinic Acid Extraction Resin

Synthesis, Characterization and Applications of Phosphinic Acid Extraction Resin
　　A novel resin containing alkyl phosphinic acid functional group has been synthesized through chloromethylation and phosphorylation reaction on styrene-divinylbenzene copolymer beads. The synthesized resin was characterized by FT-IR, 31P-NMR and elemental analysis. Some absorption parameters of lanthanides on the resin was measured by bath method.The alkyl phosphinic acid resin (APAR) has been used as a stationary phase to separate 14 lanthanide elements by normal pressure liquid chromatography. The separation of 7 light lanthanide elements has been achieved by high performance liquid chromatography withα-hydroxyl isobutyric acid as a mobile phase.
　　The APAR was also used for on-line preconcentration Magnetic lifter of trace rare earth elements (14 lanthanides and yttrium) and then determined by inductively coupled plasma mass spectrometry. REEs in seawater could be on-line concentrated on the APAR packed column (4.6 i.d.×50 mm in length), and eluted from the column with 0.5 mL 0.1 mol L-1 nitric acid within 30 s. An enrichment factor of nearly 400 was achieved for all REEs when the seawater sample volume was 200 mL, while the matrix and coexisting spectrally interfering ions such as barium, tin and antimony could be simultaneously separated. The detection limits of this proposed method for REEs were in the range from 1.43 pg L-1 of holmium to 12.7 pg L-1 of lanthanum. The recoveries of REEs were higher than 97.9%, and the precision of the relative standard deviation (R.S.D., n = 6) was less than 5%. This method has been successfully applied to the determination of soluble REEs in seawater.Vapor generation atomic fluorescence spectrometry (VG-AFS) coupled with online preconcentration on short column packed with the APAR was also developed for the determination of trace cadmium (Cd) in seawater. During the http://www.999magnet.com/ online preconcentration process, Cd in seawater was concentrated on the column while the matrix of seawater was separated flowing out of the column. Cd concentrated on the column was then eluted effectively from the column with 0.1 mol L-1 tartaric acid. When the sample volume was 200 mL, an enrichment factor 189 was achieved. The detection limit of this proposed method for Cd is 2.67 ng L-1. The recovery of Cd is 96.6% obtained by spiking the correspondence standard, and the precision (RSD) is 4.34%.

Synthesis and Structure Characterization of Polyoxometalate-Based Organic-Rare Earth Complexes

Synthesis and Structure Characterization of Polyoxometalate-Based Organic-Rare Earth Complexes
　　Combining with molecular design principle, the five polyoxometalatecompounds containing rare earth element have been synthesized by aconventional method. Their crystal structures were determined by X-raysingle-crystal diffraction, and characterized by IR spectroscopy and TGanalysis.The single crystal of {Ce(DMSO)8}PW12O40 (1) has been synthesized.In the compound, Ce3+ cations are eight-coordinated with oxygen atomsfrom eight DMSO molecules. The crystal structure strong magnets indicates that there iselectrostatic force in the compound.The single crystal of {Pr(DMSO)8}PMo12O40 (2)has been synthesized.In the compound, Pr3+ cations are eight-coordinated with oxygen atomsfrom eight DMSO molecules. The crystal structure indicates that there iselectrostatic force in the compound.The single crystal of {Pr(NMP)6}PW12O40 (3)has been synthesized. Inthe compound, Pr3+ cations are eight-coordinated with oxygen atomsfrom six DMSO molecules, two polyanions. The crystal structureindicates that the compound forms a one-dimensional zigzag chain builtfrom the alternating polyanions and cationic units throughW-Od-Pr-Od-W links.The single crystal of {[PW12O40][Y(DMF)7]}PW12O40 (4)has beensynthesized. In the compound, Y3+ cations are http://www.chinamagnets.biz/ eight-coordinated withoxygen atoms from seven DMF molecules and one polyanion. The crystalstructure indicates that the compound forms the alternating polyanionsand cationic units through Y-Od-W links.The single crystal of {[PW12O40][Sm(DMF)7])PW12O40 (5)has beensynthesized. In the compound, Sm3+ cations are eight-coordinated, withoxygen atoms from seven DMSO molecules and one polyanion. Thecrystal structure indicates that the compound forms the alternatingpolyanions and cationic units through Sm-Od-Mo links.

Synthesis, Characterization and Photoelectric Properties of Novel Ir-Re Bimetallic Complexes

Synthesis, Characterization and Photoelectric Properties of Novel Ir-Re Bimetallic Complexes
　　In this work, One novel bridge ligand Hbpy3f [Hbpy3f stands for 1-(2,2’-bipyridine-6-yl) -4,4,4-trifluorobutane-1,3-dione] and three complex-ligands Ir(rpdt)2bpy3f {fpdt represents [5-(4-fluorophenyl)-1,3-dimethyl-1H-1,2,4-triazole]}、Ir(pdt)2bpy3f [pdt represents (1,3-dimethyl-5-phenyl-1H-1,2,4-triazole)]、Ir(pdt)2phen5f [phen5f represents 4,4,5,5,5-pentafluoro-1-(1’,10’-phenanthrolin-2’-yl) -pentane-1,3-dionate] were synthesized and characterized. And Ir-RE bimetallic complexes array were synthesized and characterized using the "complex as ligand" strong magnets approach. Single crystals of three complex-ligands and Ir(pdt)2phen5f-Yb complex have been obtained, which structures and photophysical properties were investigated. The characteristic emission of EuⅢion can be observed from all iridium-europium bimetallic complexes. Complex-ligands both in Ir(pdt)2bpy3fEuCl3·4H2O and Ir(fpdt)2bpy3fEuCl3·2H2O can transfer energy to EuⅢion completely. Photophysical data implied that the characteristic emission of 613 nm from EuⅢion was sensitized by the 3MLCT energy based on complex-ligands. Furthermore, the excitation window for Ir(pdt)2bpy3fEuCl3·4H2O and Ir(fpdt)2bpy3fEuCl3·2H2O extend up to 520 nm indicating that this bimetallic complex can be used in cell imaging techniques.Ir-Yb, Nd, Er arrays were investigated and it was found that http://www.chinamagnets.biz/ NdⅢ, YbⅢions can be sensitized by Ir(pdt)2phen5f, and NdⅢion was sensitized by Ir(pdt)2bpy3f. The emission spectra between 400-650 nm of complex-ligands were compared with their bimetallic complexes, indicating that there is energy-transfer relation between complex-ligand and YbⅢ, NdⅢ, ErⅢions. 更多还原

Research of Modified NiCrAlY Coating with Nano CeO2

Research of Modified NiCrAlY Coating with Nano CeO2
　　In this research, rare earth oxides were added in NiCrAIY coatings to modify the coatings properties. Four modified NiCrAIY coatings containing different amount of rare earth oxides were prepared. The coatings were deposited by HVOF spray and plasma spray on to 45 steel and stainless steel. The hardness, thermal shock resistance, high temperature resistance and bond strength of modified and unmodified NiCrAIY coatings were evaluated.Four kinds NiCrAlY feed powders contained 0.5%, 1%, 2% and 4% rare earth oxide were prepared by ball milling. The microhardness Block neodymium magnet was evaluated on the polished cross section of coatings, and the load was 100g. The microhardness of three modified NiCrAlY coatings were improved compared to that of unmodified NiCrAlY coatings. The maximum improvement of microhardness was about 41.1% compared with unmodified coatings. Thermal shock tests were performed by water quenching method in this research. The number of cycles to failure was used to represent thermal shock resistance of coatings. All of modified NiCrAIY coatings exhibited immense improved thermal shock resistance.
　　The thermal shock cycles of unmodified NiCrAlY coatings was 45, however, the thermal shock cycles of modified coatings was increased to 66. The high temperature resistance of coatings was tested by heating persevered samples at 1000℃. After 100 hours high temperature oxidation tests, there were some spherical oxides formed on the surface of unmodified NiCrAlY coatings. However, there was no visible change on the modified NiCrAlY coatings surface. When the high temperature oxidation time was 190 hours, the amount of spherical oxides on unmodified coating surfaces increased and the volume of those oxides enlarged compared to those of at 100 hours. There were about one-third areas of unmodified coating surfaces overlapped by formed spherical oxides. In the same condition, there was still no visible change on the modified NiCrAlY coatings surface. The high temperature oxidation test results showed modified coatings possessed more excellent high temperature resistance than unmodified coatings. The bond strength of coatings was evaluated by drawing process on a universal tensile testing machine. With incensement of added CeO2, the bond strength of modified NiCrAlY http://www.chinamagnets.biz/ coatings firstly increased and then decreased. The maximum bond strength of modified coatings was improved 34.1% compared to that of unmodified coatings. Scanning electron microscope, X-ray diffractometer and optical microscope were used to analyze the microstructure of coatings. Test results showed the modified NiCrAlY coatings possessed improved properties compared to unmodified NiCrAlY coatings. The thermal shock resistance improved 50% and the bond strength improved 34.1% for modified NiCrAlY coatings compared to unmodified NiCrAlY coatings.

Synthesis and Characterization of Near-infrared Luminescent Materials Containing Erbium and Ytterbium for Organic Waveguide Amplifier

Synthesis and Characterization of Near-infrared Luminescent Materials Containing Erbium and Ytterbium for Organic Waveguide Amplifier
　　Human society is entering into an information age driven by the rapid development of technologies in areas of microelectronics, optoelectronics, computer and communications. The demands of rapid increase in information make the communication system continuously develop to high speed, big capacity and low cost. The propagation and switching speed of signals in the traditional electronic domain are inherently limited. The optical signal has a more rapid switching and modulating speed, and the photonics and optoelectronics have become research hotspot in recent years. Optical fiber telecommunication technology, depending on its tremendous and potential bandwidth resource, has become one Ball Neodymium Magnets of the important technology to support the development of communication services.All optical communication networks will benefit to realize digital communication of high speed and large capacity, and to realize“information superhighway”in the world. Amplifier whose function is to compensate the signal losses is a key device of the optical fiber communication network. Optical amplifier directly boosts up an optical signal without any conversion of the light into an electrical signal. And optical amplifying technology has become the most effective method to compensate losses. This technology which is the key to all optical communication is a revolution in the history of the fiber communication. Erbium doped fiber amplifier (EDFA) and semiconductor optical amplifier (SOA) have been successfully applied to the long-distance fiber communication. For the short-distance communication, such as local/metro networks, and especially fiber to the home (FTTH) and fiber to the curb (FTTC), a kind of medium gain, mini-volume and easy-set amplifier is urgently needed. And optical waveguide amplifier is just the amplifier which meets these demands.
　　The optical waveguide amplifiers in the 1.55μm region are mainly made of Er-doping inorganic phosphate and silicate glasses, and have already commercialized. However, the fabrication process is complex and integrating with other photonics devices is very difficult. Compared with conventional inorganic waveguide materials, polymer waveguide materials have advantages in easy process, controllable refractive index and easy integration etc.In this paper, we synthesized near-infrared luminescent erbium and ytterbium bonding-type organic complexes. Bonding-type organic complexes have been prepared and determined by FT-IR, UV-Vis-NIR spectrum, the polymeric reactivity groups(–C=C) were introduced into the formula structure of complexes. And the complexes are able to polymerize with monomer. An intense near-infrared emission at wavelength of 1.53μm was observed under the excitation of a 976nm laser light at room temperature. It has been proved that the introduction of http://www.chinamagnets.biz/  ytterbium ion could improve the PL intensity. And 1:3 is the proper molar scale of Er:Yb. Dibenzoyl methane is soluble which makes the complexes have good solubility. Through DSC and TGA analyses, the rare earth complexes show high decompound temperatures, which indicated a good thermal stability and benefit to bonding with polymer.We have synthesized Er Complex-co-MMA-co-GMA polymer, the copolymer shows excellent film-forming capability and high optical transparency, the near- infrared emission at wavelength of 1.54μm was observed, the full width at half maxium is measured to be about 80nm, this value is larger than those of silica-based glasses.. The refractive index of the copolymer Ball Neodymium Magnets  can be adjusted by doping bisphenol A epoxy. The waveguide device was fabricated by spin-coating films, using aluminum as mask and oxygen reactive ion etching.