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1.
Effects of Ni addition on liquid phase separation and giant magnetoresistance of Cu-Co alloys@孙占波 @宋晓平 @胡柱东 @祝要民 @刘剑 @杨森 @李晓园~~Project ( 5 97710 2 3)supportedbytheNationalNaturalScienceFoundationofChina ;project ( 86 3-2 -3-7-19)supportedby‘Hi-Tech’ResearchandDevelopmentProgram ;ScienceandTechnologyProject ( 2 0 0 0K10 -G11)ofShaanxiProvinceScienceOrganization…  相似文献   

2.
Separation of nickel, cobalt and copper by solvent extraction with P204   总被引:1,自引:0,他引:1  
Separation of nickel, cobalt and copper by solvent extraction with P204@钱东 @王开毅 @潘春跃 @唐有根 @蔡春林 @蒋金枝~~Project ( 99JJY2 0 0 10 )supportedbytheNaturalScienceFoundationofHunanProvince  相似文献   

3.
Formation of layer-shaped pores in TiC-Fe cermet by combustion synthesis   总被引:1,自引:1,他引:0  
Formation of layer-shaped pores in TiC-Fe cermet by combustion synthesis@范群成 @柴惠芬 @金志浩~~ProjectsupportedbytheDoctorateFoundationofXi′anJiaotongUniversity  相似文献   

4.
Four Ti-C-Fe powder mixtures, with a same molar ratio but different particle sizes of Fe and Ti, were used to measure the reaction velocity of the combustion synthesis. The results show that in the case of the finer Ti powder used, the reaction velocity of mixture with the finer Fe powder is higher than that with the coarser Fe powder. However,in the case of the coarser Ti powder used, the reaction velocity of mixture with the finer Fe powder is lower than that with the coarser Fe powder. The effect of particle size of Fe powder on reaction velocity can be explained with the previously proposed mechanisms of the combustion synthesis of Ti-C-Fe system.  相似文献   

5.
Elastic modulus is an important physical parameter of molding sand; it is closely connected with molding sand's properties. Based on theories of rheology and molding sand microdeformation, elastic modulus of molding sand was measured and investigated using the intelligent molding sand multi-property tester developed by ourselves. The measuring principle was introduced. Effects of bentonite percentage and compactibility of the molding sand were experimentally studied. Furthermore, the essential viscoelastic nature of green sand was analyzed. It is considered that viscoelastic deformation of molding sand consists mainly of that of Kelvin Body of clay membrane, and elastic modulus of molding sand depends mainly on that of Kelvin Body which is the elastic component of clay membrane between sands. Elastic modulus can be adopted as one of the property parameters, and can be employed to evaluate the viscoelastic properties of molding sand.  相似文献   

6.
PHASE transformation modeling is one of the mainchallenges in modeling of heat treatment[1].The mechanism of phase transformations is not fullyunderstood and interactive influence of differentelements,austenitizing temperature,etc.usually arenot taken in account.The mistakes in phase transformation calculationcould be extremely great if a model is based only ongrain size of prior austenite,austenitizing temperatureand elemental composition of steel.Phase transformation kinetic depends also o…  相似文献   

7.
<正>Chief editor: HUANG Bai-yun, member of the Chinese Academy of EngineeringThe Transactions of Nonferrous Metals Society of China, mainly publishes original research andreview articles in the field of nonferrous  相似文献   

8.
During bio-oxidation of sulfides, the chemical state change of sulfur is a complex and key factor. It is not only an indicator of the extent and intensity of the bio-oxidation, but also controls the property of bio-leaching medium and the period of oxidation. The chemical state of sulfur in sulfides oxidized by leaching bacteria was studied with XPS. Sulfide minerals in the arsenic-bearing gold concentrate consist of pyrite, arsenopyrite, chalcopyrite, galena, sphalerite and so on. In order to probe the pattern of the chemical state change of sulfur in the bio-oxidation residue of arsenic-bearing gold concentrate, the structure of the grains, and the surface nature of the residue, XPS test was carried out through different sputtering duration. The study of XPS clearly shows that: sulfides is progressively oxidized from the surface of minerals to the core by leaching bacteria; the chemical valence of sulfur changes from S^2- or [S2]^2- to [SO4]^2- ; sulfur in the core is in a reduction state, S^2- or [S2]^2- , but exists in an oxidation state S^6 on the surface; due to the chemical state change of sulfur, mineral phase of the bio-oxidation residue is also changed(sulfides inside, while sulfates outside); the layered structure is found in the grains of the bio-oxidation residue.  相似文献   

9.
In 1995, the Key Lab of Liquid Structure andHeredity of Metals was set up by the approval ofShandong province, but the research work on theliquid structure and heredity of materials startedin the last three decades. In 2000, combining thelab of engineering ceramic and the institute ofjoining technology in Shandong University, thelab was established as Key Lab of LiquidStructure and Heredity of Materials, by theapproval of the Ministry of Education.Currently, prof. Zhuangqi HU, prominen…  相似文献   

10.
11.
The binary complexes of terbium with benzoic acid and its derivatives (phthalic acid, iso-phthalic acid, oaminobenzoic acid, salicylic acid, sulfosalicylic acid) were synthesized and their compositions were identified by elemental analyses. UV, IR of the complexes were investigated. The UV spectra indicate that the complexes‘ ultraviolet absorption is mainly the ligands‘ absorption, but the location of peak drifts. The IR spectra show that the IR spectra of complexes are different from those of free ligands, and the band at 400 - 500 cm^-1 , due to the stretching vibration of Tb--O, is absent for free ligands. The fluorescence properties were investigated by using luminescence spectroscope, the results show that all the six complexes of terbium exhibit excellent luminescence, due to the transition from the lowest excited state ^5D4 to ^7F ground state manifold, the complexes of terbium with sulfosalicylic acid have the strongest fluorescence intensity, and is stronger than o-aminobenzoic acid-terbium, whose fluorescence intensity is regarded as the strongest one in the literature, and even stronger than some phosphor of terbium.  相似文献   

12.
铕-芳香羧酸-丙烯酰胺三元配合物的合成及发光性能研究   总被引:2,自引:0,他引:2  
以对甲基苯甲酸、大茴香酸、间氯苯甲酸、对羟基苯甲酸、苯甲酸为第一配体,丙烯酰胺为活性配体,合成了5种新的铕芳香羧酸丙烯酰胺三元配合物.通过元素分析,EDTA配位滴定分析,红外、紫外、荧光光谱分析和热分析对目标配合物的组成、结构进行了表征,并研究了它们的发光性能和热性能.结果表明,5种新的活性铕三元荧光配合物均具有良好的发光性能,各芳香羧酸向铕离子传递光能的能力为:苯甲酸>对甲基苯甲酸>大茴香酸>间氯苯甲酸>对羟基苯甲酸,若能将这些含活性配体丙烯酰胺的铕三元荧光配合物引入高分子化合物中可望合成出键合型铕高分子发光材料.  相似文献   

13.
The binary complexes of europium with benzoic acid and its derivatives (phthalic acid, m-phthalic acid,o-aminobenzoic acid, salicylic acid, and sulfosalicylic acid) were synthesized and their compositions were identified by elemental analyses. UV and IR of the complexes have been investigated. The UV spectra indicated that the complexes‘ ultraviolet absorption were mainly the ligands‘ absorption. The IR spectra showed that the IR spectra of complexes are different from those of free ligands. The fluorescence properties of them were investigated by using luminescence spectroscopy, the results showed that only three complexes appear as better luminescence, they were Eu-benzoic acid,Eu-m-phthalic acid and Eu-phthalic acid, while the others exhibited the ligands‘ wideband emission.  相似文献   

14.
1 IntroductionSomeorganiccompoundscantransferenergyabsorbedinUVregiontorareearthionswhiletheycoordinatedwiththeionsandthentherareearthionsemitcharacter isticfluoresence .Theluminousintensityandlifetimeofthecoordinatedrareearthionsismuchmorethanthoseoft…  相似文献   

15.
新型氨氧化催化合金的工业应用   总被引:7,自引:5,他引:2  
宁远涛  文飞 《贵金属》1997,18(3):1-7
研究了四元合金催化剂(网)在硝酸生产装置中的工业应用并测定其氨氧化率,铂耗率,氨耗等,与传统应用的Pt-Rh和Pt-4Pd-3.5Rh合金网比较,显示了更高的氨氧化率和硝酸生产效率,更低的铂耗率与氨耗率,更强的耐腐蚀性,抗毒化,抗粘连以及更长的使用寿命,四元合金网已在常,中,高压硝酸生产和氢氰酸生产中应用。  相似文献   

16.
The rare earth ternary complex of Eu 3+ with thenoyltrifluoroacetone,and 4,7-2NH2 phenanthroline was synthesized and well characterized by UV,fluorescent,IR spectrometry and X-ray diffractometry(XRD)as well as elemental analysis.The results show that the complex of Eu(III)emits strong red luminescence when excited by UV light,and Eu(TTA)3(2NH2-Phen)has the higher sensitized luminescent efficiency and longer lifetime than Eu(TTA)3(Phen).In device of ITO/PVK/Eu(TTA)3(2NH2-Phen)/Al,the spectra of Eu(TTA)3(2NH2-Phen)with different ratios for spin-cast film were monitored.The main emitting peak at 614 nm can be attributed to the transition of 5 D0→ 7 F2 of Eu 3+ and this process results in the enhancement of red emission from electroluminescence device.The effect and mechanism of the ligands on the luminescence properties of europium complex were discussed.The results show that the luminescence intensity of the title complexes greatly increases in comparison with that of their corresponding complexes,revealing that the second ligands form very good synergistic effect with the first ligands.The title complexes possess excellent thermal stability properties,and are hopefully developed into fine PL and EL red materials.  相似文献   

17.
Two new ternary complexes of 1-(2-thienyl)-3-(p-phenylethynylphenyl)-1,3-propanedione (HTPP) and 1,10-phenanthroline (phen) with Sm3+ and Dy3+ were synthesized. The composition of the ternary complexes was characterized as Sm(TPP)3phen and Dy(TPP)3phen, respectively, by infrared (IR) spectra, chemical analysis, elemental analysis, and thermodynamic analysis. At room temperature, under UV light excitation, the Sm3+ and Dy3+ complexes exhibit characteristic emissions of the central ions. It is found that the fluorescence intensity of Sm(TPP)3phen is stronger than that of Dy(TPP)3phen. In order to explain this phenomenon, an accurate quantum chemistry calculation was carried out, and the result is in good agreement with the experiment data.  相似文献   

18.
The stability of europium(III) complexes with substituted diglycolic acids is altered by changing the ligand rigidity. The diglycolate analog tetrahydrofuran-2,3,4,5-tetracarboxylic acid (THFTCA) achieves nearly an order of magnitude stronger binding of europium(III) in dilute acidic solutions, partly as a result of favorable complexation geometry forced by the tetrahydrofuran ring. The analogous aromatic ring systems furan-2,3,4,5-tetracarboxylic acid and furan-2,5-dicarboxylic acid, which force the carboxylate groups to assume a planar configuration, exhibit much lower affinity for europium(III) in dilute acid. The observed increase in stability for the THFTCA complex implies that one or two of the six geometric isomers of THFTCA must be dominant.  相似文献   

19.
合成了聚N-异丙基丙烯酰胺-丙烯酸P(NIPAM-co-AAc)共聚微凝胶与Eu(Ⅲ)离子、α-噻吩甲酰三氟丙酮(HTTA)的三元配合物。用透射电镜、激光光散射、Zeta电位、紫外光谱、红外光谱、荧光光谱进行了表征。结果表明,微凝胶粒径为400nm;Eu(Ⅲ)与微凝胶、HTTA之间以配位作用为主;微凝胶、HTTA和Eu(Ⅲ)之间能进行有效的能量传递。其配合物的最佳激发波长为317nm,在此激发波长下Eu(Ⅲ)有较强的荧光特征发射。  相似文献   

20.
It was found that fluorescence intensities of the complexes TbL3Phen and Tb-A-Phen (L anion of 1-indoleacetylacetone, A anion of 1-acetylaceto-3-indole acetic acid and Phen1,10-phenanthroline) are much weaker than those of binary complexes, TbL3(or A). mH2O. By comparing the emission and excitation phosphorescence spectra of Gd-Phen and Gd-L (or A) with those of Gd-L-Phen (or Gd-A-Phen), a mechanism of intramolecular energy transfer from the excited L (or A) to Phen in Gd-L-Phen (or Gd-A-Phen) is presented. This was confirmed by the observation that the lifetime for Tb-L (or A)-Phen at 77 K is much longer than that at room temperature, while the lifetimes for the complexes with no Phen at 77 K are very near to those at room temperature.  相似文献   

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