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991.
荧光灯电子镇流器是3C强制认证产品之一,了解认证要求对生产者提高产品质量非常重要。本文从认证和检测两个方面介绍此类产品的发展动态,分析了认证规则和产品标准的变化对产品质量的影响,重点介绍了新标准“第17章灯寿命结束时镇流器的状态”检测方法,阐述了其电路特点、测量方法、试验结果限值和试验程序。 相似文献
992.
基于目前电子镇流器设计中计算复杂,关键元器件参数选择困难,而且结果不够准确,本文提出一种荧光灯的简易电路模型,据此用仿真的方法来设计电子镇流器.这种方法通过简单的计算和仿真得到关键元器件参数和各个工作点的频率,电压及电流等参数.实验结果表明,该方法简单实用而且准确,适合各种荧光灯电子镇流器的设计. 相似文献
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994.
Cheng Zhang Bin Zhuge Xiaobei Zhan Huiying Fang Hong Zong Jian Zhuge 《Yeast (Chichester, England)》2013,30(4):157-163
A 3950 bp genomic fragment from Candida glycerinogenes, WL2002‐5, containing the CgGAP gene encoding a glyceraldehyde‐3‐phosphate dehydrogenase homologous to GAP genes in other yeasts using degenerate primers, was cloned and characterized with inverse PCR. Sequence analysis revealed a 1164 bp open reading frame encoding a putative peptide of 387 deduced amino acids, with a molecular mass of 36 kDa. The CgGAP protein consisted of an N‐terminal NAD+‐binding domain and a central catalytic domain. Six stress‐response elements were found in the upstream region of the CgGAP gene. The influence of CgGAP on glycolysis was investigated. Functional analysis revealed that Saccharomyces cerevisiae transformed with CgGAP was restored to the wild‐type phenotype when cultured in high‐osmolarity medium, suggesting that it is a functional GAP protein. Promoter studies in S. cerevisiae using the green fluorescent protein (gfp) gene as a reporter showed that the GAP promoter (PCgGAP) is constitutively expressed in S. cerevisiae cells grown on glucose. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
995.
996.
《Journal of Experimental Nanoscience》2013,8(3):195-206
Anticipated growth of the nanotechnology industry has motivated the development of rapid, relevant and efficient testing strategies to evaluate the biological activity and toxic potential of the growing number of novel nanoparticles. Since nanoparticles may interact with biological systems in unforeseen ways, it is important that evaluation of nanomaterial–biological interactions cover a broad range of cell types, tissues, organs and systems. Here, we use the embryonic zebrafish as a dynamic whole animal (in vivo) assay to investigate the importance of chemical composition, size, surface functionalisation and route of exposure on nanomaterial–biological interactions and delineate nanomaterials that are biologically active from those that are not. Information gained using model systems, such as the embryonic zebrafish, can be used to direct the rational development of safer, less hazardous nanoparticles. Our results demonstrate the utility of this model as an effective and accurate tool to assess the biological activity and toxic potential of nanomaterials in a short period of time with minimal cost. 相似文献
997.
《分离科学与技术》2012,47(10):1507-1513
Mesoporous silica with covalently bound salicylic acid molecules incorporated in the structure was synthesized with a one-pot, co-condensation reaction at room temperature. The as-synthesized material has a large surface area, uniform particle size, and an ordered pore structure as determined by characterization with transmission electron microscopy, thermal gravimetric analysis, and infrared spectra, etc. Using the strong fluorescence and metal coordination capability of salicylic acid, functionalized mesoporous silica (FMS) was developed to track and extract radionuclide contaminants, such as uranyl [U(VI)] ions encountered in subsurface environments. Adsorption measurements showed a strong affinity of the FMS toward U(VI) with a Kd value of 105 mL/g, which is four orders of magnitude higher than the adsorption of U(VI) onto most of the sediments in natural environments. The new materials have a potential for synergistic environmental monitoring and remediation of the radionuclide U(VI) from contaminated subsurface environments. 相似文献
998.
本文重点分析美国修订荧光灯镇流器节能新标准草案的相关背景、与现行美国标准的差异,以及对我国相关产业的影响,并提出应对该标准草案的相关建议,供社会各界参考。 相似文献
999.
探讨靶向microR-155(微小RNA-155,miR-155)放射性探针在乳腺癌细胞水平的靶向调控、摄取和分布情况,以期为活体靶向研究提供有效的候选探针。通过双功能偶联剂NHS-MAG3构建放射性~(99m)Tc标记的miR-155靶向和无义探针。置于人新鲜血清中,使用薄层层析法测定其放化纯度。转染乳腺癌MCF-7细胞后,通过western blotting评价其对miR-155靶蛋白C/EBPβ的调节作用,并测定不同时间点该探针的细胞摄取率。合成荧光蛋白FAM标记的靶向和无义探针,通过共聚焦显微镜评价荧光标记探针在肿瘤细胞内的分布情况。结果显示,~(99m)Tc标记miR-155靶向探针的标记率为97%,放化纯度大于98%,放射性比活度为3.75GBq/μg。在人新鲜血清中12h,放化纯度大于95%。与未处理细胞对比,未标记和标记的miR-155靶向探针均能上调MCF-7细胞内C/EBPβ蛋白表达水平。随着孵育时间延长,~(99m)Tc标记的miR-155靶向探针在MCF-7肿瘤细胞的细胞摄取率明显高于对照组。荧光标记的miR-155靶向探针在MCF-7细胞中24h显示出稳定、高效的靶向分布。结果表明,miR-155靶向的放射性探针在乳腺癌细胞水平具有良好的靶向性和生物活性,具有潜在的体内肿瘤显像应用价值。 相似文献
1000.
L. V. Markova N. K. Myshkin V. M. Makarenko M. S. Semenyuk H. Kong H. -G. Han S. V. Ossia 《Journal of Friction and Wear》2007,28(1):32-37
Current interest in evaluating the oil condition in tribosystems is discussed. Fluorescent express-methods for oil condition monitoring are analyzed and their main advantages and disadvantages are noted. The basic concept of the fluorescent method developed for evaluating oil oxidation rate by recording the shift of fluorescence spectrum to the long-wave region is described. The realization of the method is exemplified and the results of the analysis of fresh and worked hydraulic oils with the developed fluorescent sensor are given. The sensor can be used as both built in the oil line and a portable device under manufacture and laboratory conditions. 相似文献