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121.
122.
两种稀土卟啉配合物与大肠杆菌作用的微量热研究 总被引:5,自引:0,他引:5
用LKB-2277生物活性检测系统测定了新合成的阳离子型稀土卟啉配合物{[Re(TMP)(H2O)3]Cl, Re=Y、Yb, TMP=5, 10, 15, 20-四(4’-甲氧基苯基)卟啉}在37 ℃时对大肠杆菌作用的产热曲线,根据产热曲线求算了在稀土卟啉配合物作用下,大肠杆菌生长代谢的速率常数k,抑制率I,传代时间tG和半抑制浓度cI,50等热动力学参数.结果表明,稀土卟啉配合物在低浓度下对大肠杆菌有刺激作用,高浓度下为抑制作用,[Yb(TMP)(H2O)3]Cl的半抑制浓度cI,50为143 mg•L-1,其对大肠杆菌的抑制作用优于[Y(TMP)(H2O)3]Cl. 相似文献
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针对垂直向列型彩色滤光膜硅覆液晶微显示器件中的微型彩色像素建立了三维光学模型. 首先, 对彩色液晶器件的机电特性进行了分析; 其次, 利用扩展琼斯矩阵计算出器件的光反射率; 最后, 采用标准RGB协议将所研究的垂直向列型彩色滤光膜硅覆液晶微显示器件中各像素点的光反射特性还原成彩色图像. 用上述过程所建立的三维光学模型进行了垂直向列型彩色滤光膜硅覆液晶微显示器件的光学特性研究, 并与实验数据进行了比较. 比较结果显示, 模拟得到的垂直向列型彩色滤光膜硅覆液晶微显示器件的光学特性与实验结果非常符合. 相似文献
127.
A‐D‐A Type Small Molecules Based on Boron Dipyrromethene for Solution‐Processed Organic Solar Cells
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Liangang Xiao Dr. Hongda Wang Ke Gao Dr. Lisheng Li Chang Liu Prof. Dr. Xiaobin Peng Prof. Dr. Wai‐Yeung Wong Prof. Dr. Wai‐Kwok Wong Dr. Xunjin Zhu 《化学:亚洲杂志》2015,10(7):1513-1518
The unique properties of boron dipyrromethene (BODIPY) dyes including facile synthesis, high absorption coefficients, and delocalized molecular orbitals as well as excellent photochemical and thermal stability, make them promising as materials for organic solar cells. Accordingly, in this study three A‐D ‐A structural small molecules of BDTT‐BODIPY, FL‐BODIPY, and TT‐BODIPY have been synthesized, in which two BODIPY acceptor units are symmetrically conjugated to 4,8‐bis(5‐(2‐ethylhexyl) thiophen‐2‐yl)benzo[1,2‐b:4,5‐b]dithiophene (BDTT), 9,9‐dioctyl‐9H‐fluorene (FL), and thieno[3,2‐b]thiophene (TT) donor cores, respectively. The manipulation of the structural parameters significantly improves the performances of the BHJ OSCs, which show power conversion efficiencies of 4.75 %, 1.51 %, and 1.67 % based on [6,6]‐phenyl C71‐butyric acid methyl ester (PC71BM) as the acceptor material and BDTT‐BODIPY, FL‐BODIPY, and TT‐BODIPY as the donor materials, respectively. 相似文献
128.
Rapid amplification of genetically modified organisms using a circular ferrofluid-driven PCR microchip 总被引:1,自引:0,他引:1
Yi Sun Yien-Chian Kwok Peter Foo-Peng Lee Nam-Trung Nguyen 《Analytical and bioanalytical chemistry》2009,394(5):1505-1508
The use of genetically modified organisms (GMOs) as food and in food products is becoming more and more widespread. Polymerase
chain reaction (PCR) technology is extensively used for the detection of GMOs in food products in order to verify compliance
with labeling requirements. In this paper, we present a novel close-loop ferrofluid-driven PCR microchip for rapid amplification
of GMOs. The microchip was fabricated in polymethyl methacrylate by CO2 laser ablation and was integrated with three temperature zones. PCR solution was contained in a circular closed microchannel
and was driven by magnetic force generated by an external magnet through a small oil-based ferrofluid plug. Successful amplification
of genetically modified soya and maize were achieved in less than 13 min. This PCR microchip combines advantages of cycling
flexibility and quick temperature transitions associated with two existing microchip PCR techniques, and it provides a cost
saving and less time-consuming way to conduct preliminary screening of GMOs.
Figure Schematic of the circular ferrofluid-driven PCR microchip 相似文献
129.
A method was developed for high-throughput determinations of 7 elements in food samples, namely antimony (Sb), arsenic (As), cadmium (Cd), chromium (Cr), lead (Pb), mercury (Hg), and tin (Sn). The samples were digested by closed-vessel microwave-assisted digestion using concentrated nitric acid (HNO3) as the medium, followed by microwave- assisted evaporation to concentrate the sample solutions before dilution to the desired volume. The microwave-assisted evaporation procedure effectively reduced the final acid concentration to around 8% before analysis by inductively coupled plasma-mass spectrometry (ICP-MS). This reduction allows determination by ICP-MS to proceed without further sample dilution, which would affect the detection limit. The method was validated, and method recoveries for As, Cd, Cr, Pb, and Hg were within the certified ranges of the chosen certified reference materials. Recoveries of the 7 elements from spiked samples ranged from 93.1 to 103.6%. The standard uncertainties of precision for the 7 elements were between 3.1 and 4.3%. Interlaboratory comparison studies for As, Cd, and Pb gave z-scores ranging from -0.2 to 0.3. 相似文献
130.
An improved method based on streaming potential and streaming current was proposed to determine zeta potential and surface conductance of porous material simultaneously. In the electrokinetic generation mode, a resistor is connected to the generator and by measuring the voltage drop across resistors with different resistance, a true streaming current can be determined. The zeta potential and surface conductivity can be obtained simultaneously from their relation to streaming potential and streaming current. The electrode and ion concentration polarization effects during the measurement were also discussed. The resistance from channel ends to electrodes, which has typically been ignored in the literature, was shown to have a significant influence on the calculated zeta potential and surface conductance. Ignorance of this resistance would lead to underestimation of both zeta potential and surface conductance values. 相似文献