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1.
A simple, sensitive and selective method has been developed for the determination of protein using resonance light scattering (RLS) technique. The method is based on the interaction of protein and arsenazo-DBC-Al(3+) in the pH range of 5.0-7.0, which causes a substantial enhancement of the resonance scattering signal of arsenazo-DBC-Al(3+) in the wavelength range of 300-550 nm with the maximum RLS platform at 405-420 nm. With this method, 2.50-50.00 mug ml(-1) of bovine serum albumin (BSA) and 2.50-60.00 mug ml(-1) of human serum albumin (HSA) can be determined, and the detection limits, calculated three times the standard deviation (S.D.) of six blank measurements, for BSA and HSA were 123.4 and 89.6 ng ml(-1), respectively. Moreover, the method is free from interference from many amino acids and metal ions. The method, with high sensitivity, selectivity and reproducibility, was satisfactorily applied to the determination of total protein in human serum samples. Mechanism studies indicated that arsenazo-DBC-Al(3+) could bind to BSA depending mainly on electrostatic forces, which results in enhanced RLS in the arsenazo-DBC-Al(3+)-protein system. 相似文献
2.
Shaobin Miao Zhan Yu Qian-Feng Zhang Yinglin Song Alexander Rothenberger Wa-Hung Leung 《Journal of Cluster Science》2006,17(3):495-507
Two isostructural crown-like heteroselenometallic cluster compounds, [Et4N]4[(μ5-WSe4)(CuX)5(μ-X)2] (X = Cl 1, Br 2), were prepared from the reactions of [Et4N]2[WSe4] with CuX and [Et4N]X· xH2O in the presence of 2-picoline and characterized by single-crystal diffraction analysis. The [(μ5-WSe4)(Cu-X)5(μ-X)2]4− anions in the cluster compounds consists of five CuX fragments coordinated to the five edges of the tetrahedral [WSe4]2− moiety along with two bridging halides connected to each of the two pairs of the symmetric copper atoms, exhibiting a novel
crown-like core structure. The nonlinear optical absorption and refraction of cluster compound 2 were determined to be α2 = 6.15 × 10−10 m/W and n
2 = 4.18 × 10−11 esu, respectively. 相似文献
3.
Qian-Feng Zhang Richard D. Adams Dieter Fenske 《Journal of inclusion phenomena and macrocyclic chemistry》2005,53(3):275-279
The self-assemblies of two pyrogallol[4]arenes held together by 48 intermolecular hydrogen bonds stably associate in the form of spherical hexameric capsules. The molecular structures of two hexameric capsules with large interior space were analyzed by single crystal X-ray crystallography. 相似文献
4.
Qian-Feng Zhang Yu-Jie Liu Richard D. Adams Alexander Rothenberger Dieter Fenske Wa-Hung Leung 《Journal of Cluster Science》2006,17(3):445-455
Treatment of tetracopper(I)-phosphonitocavitand [1·Cu4(μ-Cl)4(μ4-Cl)] (2) (1 = tetraphosphonitocavitand [rccc-2,8,14,20-tetrakis-(iso-butyl)-phosphonitocavitand (C44H48O8P4Ph4)]) with PhSeSiMe3 in THF at low temperature afforded a novel polyanionic cluster [pyH]6[(CuCl)9(μ3-SePh)5(μ4-SePh)] (4) as a major product along with a new tetracopper(I)-phosphonitocavitand (3) with a centered μ3-Cl. Molecular structure of anionic cluster in 4 consists of six PhSe− bridging ligands containing five μ3-SePh and one exceptional μ4-SePh bridging nine copper atoms, of which eight copper atoms have trigonal coordination geometry and the other has distorted
tetrahedral geometry.
Dedicated to Professor Han-Qin Liu on the occasion of his 70th birthday. 相似文献
5.
Man-Kit Lau Qian-Feng Zhang Wing-Tak Wong Wa-Hung Leung 《Journal of organometallic chemistry》2004,689(14):2401-2410
Treatment of [M(Buppy)2Cl]2 (M=Ir (1), Rh (2); BuppyH=2-(4′-tert-butylphenyl)pyridine) with Na(Et2NCS2), K[S2P(OMe)2], and K[N(Ph2PS)2]2 afforded monomeric [Ir(Buppy)2(S∧S)] (S∧S=Et2NCS2 (3), S2P(OMe)2 (4), N(PPh2S)2 (5)) and [Rh(Buppy)2(S∧S)] (S∧S=Et2NCS2 (6), S2P(OMe)2 (7), N(PPh2S)2 (8)), respectively. Reaction of 1 with Na[N(PPh2Se)2] gave [Ir(Buppy)2{N(PPh2Se)2}] (9). The crystal structures of 3, 4, 7, and 8 have been determined. Treatment of 1 or 2 with AgOTf (OTf=triflate) followed by reaction with KSCN gave dinuclear [{M(Buppy)2}2(μ-SCN)2] (M=Ir (10), Rh (11)), in which the SCN− ligands bind to the two metal centers in a μ-S,N fashion. Interaction of 1 and 2 with [Et4N]2[WQ4] gave trinuclear heterometallic complexes [{Ir(Buppy)2}2(μ-WQ4)] (Q=S (12), Se (13)) and [{Rh(Buppy)2}2{(μ-WQ)4}] (Q=S (14), Se (15)), respectively. Hydrolysis of 12 led to formation of [{Ir(Buppy)2}2{W(O)(μ-S)2(μ3-S)}] (16) that has been characterized by X-ray diffraction. 相似文献
6.
Qin Shun-Shun Liu Jing-Long Hu Feng Jia Ai-Quan Xu Chao Zhang Qian-Feng 《Journal of Cluster Science》2021,32(6):1593-1599
Journal of Cluster Science - Interaction of [Pb(SiPr)2]n with 1.5 equiv. of AgNO3 in DMF under aerobic conditions at room temperature gave a cationic lead-centered thiolate cluster... 相似文献
7.
The title complex [CpIr{N(Ph2PS)2}(N3)](N(Ph2PS)2=bis(diphenylthiophosphoryl)amide,Cp=pentamethylcyclopentadienyl) has been prepared and characterized by X-ray diffraction analysis.It crystallizes in monoclinic,space group P21/n with a=11.6946(1),b=18.9273(2),c=15.7859(1),β=105.731(1)°,V=3363.29(5)3,Z=4,Mr=817.92,Dc=1.615g/cm3,μ(MoKα)=4.219 mm-1,F(000)=1624,S=1.028,the final R=0.0355 and wR=0.0848 for 5987 observed reflections with Ⅰ 2σ(Ⅰ) and 363 variables.The molecular structure of 1 consists of discrete monomeric molecule with a distorted octahedral configuration around the iridium atom,having a Cp ring at one face and bonded with a chelating bis(diphenylthiophosphoryl)amide group as well as a terminal azido ligand.The average Ir-S and Ir-N bond lengths are 2.416(1) and 2.121(5),respectively. 相似文献
8.
9.
L.Z. Pei Y. Yang L.J. Yang C.G. Fan C.Z. Yuan Qian-Feng Zhang 《Solid State Communications》2011,151(14-15):1036-1041
Large-scale Zn2GeO4 nanorods with a length of about 10 μm have been synthesized via a facile hydrothermal process in the absence of any surfactant. The synthesized nanorods are single crystals with a rhombohedral phase. The dependence on the growth conditions, such as reaction temperature, reaction time, compactness and GeO2 concentration, of the formation, morphologies and sizes of the Zn2GeO4 nanostructures has been investigated. Proper selection and combination of the growth conditions are the key aspects to control the formation, morphologies and sizes of the Zn2GeO4 nanostructures. The nucleation and crystalline growth mechanism are proposed to explain the formation and growth of Zn2GeO4 nanorods. The photoluminescence spectrum of the Zn2GeO4 nanorods exhibits three fluorescence emission peaks centered at 421, 488 and 529 nm when the excitation wavelength is 235 nm. 相似文献
10.
采用溶胶凝胶法合成的La1.9Y0.1Mo2O9纳米晶粉体, 结合微波烧结技术制备出不同晶粒度的La1.9Y0.1Mo2O9块体样品. 利用X射线衍射仪(XRD)、高分辨透射显微镜(HRTEM)、场扫描显微镜(SEM)对粉体及陶瓷块体的物相、 形貌进行了表征, 利用交流阻抗谱仪测试了样品不同温度下的电导率. 实验结果表明, 掺Y的La1.9Y0.1Mo2O9能将高温立方β 相稳定到室温; 块体样品致密均匀, 平均晶粒度范围在60 nm–4 μm之间; 致密度高的样品表现出高的电导率, 其中900 ℃烧结样品的电导率600 ℃时高达0.026 S/cm, 比固相反应法制备的La1.9Y0.1Mo2O9样品高出约1倍. 总结认为样品的致密性对电导率影响较大, 是通过影响晶界电导率来影响总电导率的, 样品的晶粒度(在60 nm–4 μm范围内)对电导率的影响还不能确定.
关键词:
氧离子导体
1.9Y0.1Mo2O9')" href="#">La1.9Y0.1Mo2O9
细晶粒陶瓷
微波烧结 相似文献