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31.
无机纳米粒子作为生物探针在生物分析中的研究进展 总被引:3,自引:0,他引:3
介绍了无机纳米粒子在生物分析领域的研究进展分别从生物分子与纳米粒子的耦联方式、检测生物分子的纳米金探针、核酸或蛋白质修饰的其它纳米探针以及生物纳米技术的应用前景4个方面对该领域的发展进行了概述。 相似文献
32.
IR‐to‐visible up‐conversion fluorescent nanocrystals of hexagonal‐phase NaYF4:20 %Yb,2 %Er and NaYF4:20 %Yb,2 %Tm have been synthesized by decomposition of multiprecursors of CF3COONa, (CF3COO)3Y, (CF3COO)3Yb, and (CF3COO)3Er/(CF3COO)3Tm in oleylamine at 330 °C. The average particle size is 10.5 ± 0.7 nm (from random measurements of 200 particles from five transmission electron microscopy images) and 11.1 ± 1.3 nm (from dynamic‐light‐scattering measurements). The up‐conversion fluorescence intensity of the hexagonal nanocrystals in this work is much higher than that of other cubic‐phase NaYF4:Yb,Er nanocrystals, including the ones in this work (by a factor of 7.5). Mechanisms for nucleation and growth of the hexagonal‐phase nanoparticles are proposed. These nanocrystals are easily dispersed in organic solvents, producing a transparent colloidal solution. The hydrophobic surfaces of the particles are made hydrophilic using a bipolar surfactant. These nanoparticles and their dispersions in various media have potential applications in optical nanodevices and bioprobes. 相似文献
33.
In proportion to the environmental pollution problems caused by organotin compounds, the genotoxicities of tin compounds in the environments have become of interest so as to estimate their safety in recent years. In this work, isolated λ-DNA (double-strand DNA) was incubated with inorganic tin(II) and tin(IV) and five organotin compounds [n-butyltin trichloride, di(n-butyltin) dichloride, methyltin trichloride, dimethyltin dichloride and trimethyltin chloride] in reaction systems both with and without hydrogen peroxide (H2O2) content. The tin compounds tested in this study did not induce DNA breakage in the absence of hydrogen peroxide. Divalent inorganic tin (SnCl2) and tetravalent inorganic tin (SnCl4) caused DNA breakage in the presence of hydrogen peroxide (10 mM), and the DNA damage activity of inorganic tin was much more potent in divalent inorganic tin (SnCl2) than in tetravalent inorganic tin (SnCl4). Divalent inorganic tin (SnCl2) induced DNA breakage in a concentration-dependent fashion at concentrations greater than 0.1 mM of SnCl2 in the presence of hydrogen peroxide (10 mM). DNA breakage was not caused by n-butyltin compounds and methyltin compounds either in the presence or in the absence of hydrogen peroxide. 相似文献
34.
提出了一种用于修正光学神经网络硬件系统误差的虚拟神经网络模型,光学实验结果表明该网络能够有效地消除硬件系统误差对实验结果的影响。 相似文献
35.
针对拼接结构的高分辨率彩色等离子体大屏幕系统的应用,指出了刷新型电路模式的不足之处,提出了一种混合型模式的驱动电路。从彩色模块ACPDP的结构特性出发,详细讨论了该电路的工作原理,驱动波形以及放电过程。 相似文献
36.
The influence of humic substances on sorption and methylation processes for inorganic- and organotin species is presented. Four sediment samples from different locations of the Rivers Elbe, Mulde and Spittelwasser, Germany, with different organotin and humic contents were selected to extract the humic and fulvic acids. The various fractions—the original sediment, the humic acid, the fulvic acid and the residual sediment—were analysed for their organotin content. The individual buyltin species show quite different distribution patterns. Monobutyltin is found mostly associated with humic acids. Dibutyltin shows a nonunique behaviour. At low total organotin content, dibutyltin is found bonded to humic and fulvic acids, whereas at high organotin content dibutyltin is distributed more with the residual sediment. Most of the tributyltin remains in the sediment unextracted; only small quantities of it are in the fulvic acid fraction. Tetrabutyltin is only in the humic acid fraction when it binds to humic matter; it mostly remains in the sediment. General observations indicate that ionic butyltin species bind to fulvic acids whereas the non-polar tetrabutyltin is not found in the fulvic acid fractions in any of the samples. The appearance of monomethyl- and dimethyl-tin species in the humic and fulvic acid fractions after the alkaline extraction was surprising. There is a correlation between the humic content of the sample and the formation of methyltin species. Evidence is provided by experiments that humic substances act as methylation agents. 相似文献
37.
38.
Teruhiko Kai Yasunori Suma Shuichiro Ono Takeo Yamaguchi Shin‐ichi Nakao 《Journal of polymer science. Part A, Polymer chemistry》2006,44(2):846-856
We have investigated the effect of the surface state and surface treatment of the pores of an inorganic substrate on the plasma‐grafting behavior of pore‐filling‐type organic/inorganic composite membranes. Shirasu porous glass (SPG) was used as the inorganic substrate, and methyl acrylate was used as the grafting monomer. The grafting rate increased as the density of silanol on the SPG substrate increased. This result suggests that radicals are generated mainly at the silanol groups on the pore surface by plasma irradiation. The SPG substrates were treated with silane coupling agents used to control the mass of organic material bonded to the pore surface. The thickness of the grafted layer became thinner as the mass of organic material bonded to the pore surface of SPG increased. This decrease in the thickness of the grafted layer could be explained by the decrease in the penetration depth of vacuum ultraviolet rays contained in plasma having a wavelength of less than 160 nm that generated radicals in the pores of the substrate. The thickness of the grafted layer inside the SPG substrates could be controlled through the control of the mass of organic material bonded to the pore surface of the SPG substrate. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 846–856, 2006 相似文献
39.
海螵蛸入药部分和废弃部分8种无机元素分析 总被引:3,自引:0,他引:3
为合理开发利用海螵蛸 ,用原子吸收分光光度法测定了海螵蛸中入药部分和废弃部分中8种人体必需无机元素含量。结果表明 ,入药部分和废弃部分中钙含量丰富 ,分别达到 742 1 3× 1 0 - 3和 65 9 76× 1 0 - 3。入药部分铜、铁含量较废弃部分高 ,分别为 9 41× 1 0 - 6 、 91 86× 1 0 - 6 和2 3 5× 1 0 - 6 、 2 5 7× 1 0 - 6 。废弃部分含锌丰富 ,为 3 5 3 62× 1 0 - 6 ,数倍于入药部分 64 65× 1 0 - 6 。可见海螵蛸入药部分和废弃部分均具有良好的开发前景 相似文献
40.
J. Goworek W. Stefaniak Agnieszka Kierys Mariola Iwan 《Journal of Thermal Analysis and Calorimetry》2007,87(1):217-222
Mesoporous silica material of MCM-41 type was synthesized by co-condensation
of highly concentrated octyltriethoxysilane (OTEOS), octadecyltriethoxysilane
(ODTEOS) and tetraethoxysilane (TEOS). The obtained hybrid materials were
characterized using XRD, TG-DSC and low temperature adsorption/desorption
of nitrogen. It was shown that the applied method of synthesis allows to obtain
silica of MCM-41 type with a high degree of hydrocarbon saturation. 相似文献