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91.
Lan Zhao Yongdong Liu Yinjue Wang Yongdong Huang Xiunan Li Yan Li Guanghui Ma Zhiguo Su 《Biomedical chromatography : BMC》2013,27(9):1089-1091
To study the leakage at different solution pH values, IgG Sepharose 6FF®, a commercially available immunoadsorbent, was used as a model. The leaked substance consists of three parts: (1) ligands and its fragments; (2) ligands plus matrix fragments in which ligands are chemically attached to the adsorbent matrix; and (3) matrix fragments. Buffer solution pH values had a great effect on both the kinetics and the amount of ligand leakage. Cross‐linking of the adsorbent matrix could reduce both matrix leakage and antibody leakage at pH 3.0, but its effect was limited at pH 11.0 for ligand leakage. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
92.
93.
剪切散斑:一种光学测量技术及其应用 总被引:3,自引:0,他引:3
本文综述了剪切散斑测量技术及其成功的应用领域。剪切散斑技术是一种基于激光的全场、非接触表面变形(位移或应变)测量技术,它无需特殊的隔震装置,克服了因参考光束给全息干涉技术所带来的诸多限制。因此,它是用于现场测量的一个有效工具。剪切散斑测量技术已经得到了工业界的普遍认同,尤其是在工业无损检测方面更显示出了它的极大优势,它可以通过识别被诱发的异常变形来显示物体的内部缺陷。剪切散斑的应用还包括应变测量、材料特性表征、残余应力评估、泄漏探测、振动分析和三维形貌测量等。 相似文献
94.
A flow gas low-pressure multi-wire proportional chamber(LPMWPC)with an active area of 180 mm×80 mm has been developed for the flying time test of the recoil nuclei on super heavy nuclear experiments.The LPMWPC detector can be operated in single as well as double step operational modes.In the case of double step operational mode with a high gas amplification factor,signals fromα-particles reside well above the electronic noise.The gas leakage rate and time resolution obtained from theα239Pu source are shown and discussed at the condition of 3 mbar Isobutane gas.It was shown that the time resolution was better than 2.9 ns at the best work condition,and the detecting efciency was larger than 98%at the low energyαparticles.So the LPMWPC is fit to measure the flying time in the super heavy nuclear fragments experiment. 相似文献
95.
When using laser interferometer to detect surface acoustic wave at fluid–solid interface, there are two factors which will cause the optical path length variation of the probe laser beam: interface deformation, and refractive index changes in fluid induced by acoustic leakage. Influence of acoustic leakage on laser interferometric detection for surface acoustic wave is researched here. A metal plate immersed in an infinite fluid is used as a physical model. Interface deformation due to laser-induced acoustic wave and pressure in fluid due to acoustic leakage are computed for select cases by finite element method. The optical path length variation caused by the two factors are calculated respectively and compared. The results show that the influence of acoustic leakage increases with the increasing acoustic impedance matching of fluid and solid, the peak-to-peak of influence degree increases linearly with the increasing acoustic impedance of fluid, and that decreasing the distance between the interferometer and interface can effectively reduce the influence of acoustic leakage. 相似文献
96.
研究了一种脉冲信号激励的漏磁检测系统;利用USB数据采集卡I/O口输出脉冲方波信号经过功率放大环节生成激励信号,通过数据采集卡触发采样功能实现检测信号的同步采样;基于Labview软件搭建了漏磁检测虚拟仪器平台,实现了漏磁检测信号的采集、调理、储存、回放和分析功能;通过实验对加工有宽度为2 mm深度分别为2 mm、5 mm、10 mm的3个裂纹缺陷的钢样本进行检测,应用霍尔传感器检测漏磁场信号;检测信号经过调理和采集,在电脑中实时显示漏磁信号随时间的变化波形;通过分析回放采样信号的峰值和峰值到达时间评估缺陷的位置和深度;实验结果表明缺陷深度越大采样信号的峰值越大,峰值到达时间越长。 相似文献
97.
Comparison of electrical characteristic between AIN/GaN and AIGaN/GaN heterostructure Schottky diodes 下载免费PDF全文
Ni/Au Schottky contacts on A1N/GaN and A1GaN/GaN heterostructures are fabricated. Based on the measured current-voltage and capacitance-voltage curves, the electrical characteristics of AlN/GaN Schottky diode, such as Schottky barrier height, turn-on voltage, reverse breakdown voltage, ideal factor, and the current-transport mechanism, are analyzed and then compared with those of an A1GaN/GaN diode by self-consistently solving Schrodinger's and Poisson's equations. It is found that the dislocation-governed tunneling is dominant for both AlN/GaN and AlGaN/GaN Schottky diodes. However, more dislocation defects and a thinner barrier layer for AlN/GaN heterostrncture results in a larger tunneling probability, and causes a larger leakage current and lower reverse breakdown voltage, even though the Schottky barrier height of AlN/GaN Schottky diode is calculated to be higher that of an A1GaN/GaN diode. 相似文献
98.
Qian Yang Qiang Xu Mushtaq Sobhan Qingqing Ke Franklin Anariba Khuong P. Ong Ping Wu 《固体物理学:研究快报》2014,8(7):653-657
Sn4+‐doped BiFeO3 (BFO) nanofibers have been fabricated by sol–gel based electrospinning method with nanofiber diameter in the range of 30–100 nm in the annealed state. The leakage current density dropped by two orders of magnitude in 3% Sn‐doped BFO nanofibers compared to undoped BFO samples. Our density functional theory (DFT) simulation results indicate that Sn4+ prefers to occupy the Fe3+ site in BFO with a formation energy of 1.89 eV. The impurity Sn acts as a shallow donor with a low transition energy level of 41 meV. Furthermore, an enhancement in the saturation magnetization was simultaneously observed for 3% Sn‐doped nanofibers, which correlated well with our theoretical calculations. In other words, by carefully tailoring the degree of Sn doping in BFO nanofibers, we can reduce the leakage current and concurrently enhance the magnetic moment. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
99.
In 2007, Wang et al. [M. Y. Wang and F. L. Yan, Chin. Phys. Lett. 24 (2007) 2486] proposed a three-party simultaneous quantum secure direct communication (3P-SQSDC) scheme with EPR pairs. Recently, Chong et al. [S. K. Chong and T. Hwang, Opt. Commun. OPTICS-15438 (2010(online))] proposed an enhancement on Wang et al.'s scheme. The communications in Chong et al.'s 3P-SQSDC can be paralleled and thus their scheme has higher efficiency. However, we find that both of the schemes have the information leakage, because the legitimate parties' secret messages have a strong correlation. This kind of security loophole leads to the consequence that any eavesdropper (Eve) can directly conjecture some information about the secrets without any active attack. 相似文献
100.