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991.
992.
微孔滤膜富集分光光度法测定铜 总被引:1,自引:0,他引:1
1引言利用微孔滤膜分离和富集样品中的痕量成分,是近年来发展的一项新技术。此技术是依据试样的体积与测定时的有机溶剂的体积比达到富集的目的。由于可高倍数富集及选用有机溶剂溶解收集物及膜,大大改善了检测限;而且过滤装置简易并可用常法测定,具有良好的应用前景。新亚铜灵(NCP)对一价铜来说,几乎是特效试剂,但其测定灵敏度较低,使其应用受到了限制。我们研究了Cu(I)-NCP显色体系,经过微孔滤膜富集后,用二甲基亚现将膜及络合物溶解,然后在分光光度计上测定,其灵敏度大大提高。本方法体系简单,干扰少,选择性和灵敏… 相似文献
993.
994.
Peptide dendrimers are attractive synthetic polymers and have been widely used as a new generation of biomaterials in recent years. Peptide dendrimers, as well as general dendrimers, may be synthesized to reach nano sizes, and display well-defined architectures, highly-branched structures, high density of functional terminal groups, and controllable molecular weights. On the other hand, peptide dendrimers have properties similar to proteins and some special characteristics, such as good biocompatibility, water solubility and resistance to proteolytic digestion. Due to these advantages, peptide dendrimers have received considerable attention in biomedicine. This review focuses on the development of peptide dendrimers with emphasis on their applications both in diagnostics and in therapy. 相似文献
995.
Hua-Gui Zhu Guo-Qiang Huang Cui-Lan Luo 《International Journal of Theoretical Physics》2012,51(11):3508-3513
We investigate we investigate the quantum Fisher information and phase sensitivity in Yurke-like state superposed by two special multi-particle states and a symmetric state with relative phase. By studying the influences of superposition coefficients and relative phase on the maximal quantum Fisher information and phase sensitivity, we reveal some entanglement properties of Yurke-like state. 相似文献
996.
Lu Han Yan-Ru Ma Lai-Chen Chen Shu-Min Huo Tao-Run Qiu Rong-Hua Zeng Qun-Hui Meng Yi-Fan Luo 《Journal of chemical crystallography》2011,41(4):596-600
Abstract
A new 4d–4f coordination polymer, [AgGd(pyzc)2(ox)·H2O)] (1) [pyzc = Pyrazine-2-carboxylate, ox = oxalate] has been successfully synthesized under hydrothermal conditions and structurally determined by single-crystal X-ray diffraction, and characterized by elemental analysis, infrared spectroscopy, thermogravimetric analysis and power X-ray diffraction. Single-crystal X-ray analysis reveals that it crystallizes in the monoclinic space group P2 1 /c with a = 10.0746(1) ?, b = 18.642(1) ?, c = 8.0525(2) ?, β = 112.470(1)°, Mr = 617.34, Z = 4, V = 1505.6(2) ?3, μ = 5.732, F(000) = 1164. The Gd(III) ion is nine-coordinated by two O-donors and two N-donors of two different chelating pyzc ligands, four O-donors of two different chelating oxalate ligands, and one O-donor of another carboxylate group of one pyzc ligand. The compound represents a 3D microporous polymeric network constructed by gadolinium–oxalate chains and Ag-pyzc subunits. 相似文献997.
Yangjun Xia Junfeng Tong Xia Ren Jie Luo Nong Wang Hongbing Wu Duowang Fan 《Polymer Science Series B》2010,52(9-10):614-620
Series of high molecular weight, readily soluble copolymers were synthesized by Suzuki palladium catalyzed coupling reaction from 9,9-dioctylfluorene and 2,3-dimethylnaphthopyrazine. The absorption, electrochemical and photoluminescence properties of the copolymers were studied. The external electrolu-minescence efficiencies in the devices of configuration indium-tin oxide/polyethylenedioxythiophene-polystyrene sulfonic acid/poly(fluorene-naphthopyrazine)/barium/aluminium varied with the copolymers composition, and the electroluminescence emission peaks of the copolymers were red-shifted from 530 nm to 584 nm as 2,3-dimethylnaphthopyrazine mole contents increasing from 0.5% to 30%. The best device performance was observed for devices fabricated with the copolymer of 2,3-dimethylnathphpyrazine 5% mole contents, showed maximum external quantum efficiency of 1.38% and electroluminescence peaks at around 537 nm. 相似文献
998.
999.
You-Jun Fu Zhang-Shou Gao Xun Sun Shen-Lai Wang Yi-ping Li Hong Zeng Jian-Ping Luo Ai-Dong Duan Ji-Yang Wang 《Progress in Crystal Growth and Characterization of Materials》2000,40(1-4):211-220
The synthesis of KDP from its raw material has been found exist in the growth solution. In the crystal growth experiment, significant extension of specific faces was observed at low dopant concentration. At high doping concentration, the growth rate of the whole crystal decreased with no significant habit modification. The inhibiting effects of phosphite and other H-bonding anionic ions on the growth of pyramidal faces are discussed. Rapid growth rate experiments have been carried out with purified material and an averaged growth rate of 18.6mm/day was obtained. 相似文献
1000.
C. Hu L. Liu Z. Zhao X. Chen Q. Feng X. Luo 《Applied physics. B, Lasers and optics》2009,96(2-3):439-443
We demonstrate a nonsymmetrical composite metallic structure with realistic material parameters. This structure can realize double magnetic responses in near-infrared (NIR) range (0.92 μm) and in visible range (0.61 μm), which can be attributed to two different modes of magnetic coupling. The difference of the index dependence of two magnetic responses is due to the influence of metal on LC model at optical frequencies. The multimode magnetic responses may provide us a new way to design special nano-optical devices at high frequencies. We also show that magnetic response has larger sensitivity to the local index of dielectric than plasmon resonance and suggest a possible approach in detecting the local index of the dielectric surrounding metamaterials. 相似文献