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991.
992.
GU Hongen 《Chinese Journal of Lasers》1995,4(2):111-116
Low-TemperatureSpectralPropertiesandZero-PhononTransitionsofAlkaliHalideCrystalMaterialsBombardedwithElectronsandImplantedwit... 相似文献
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GAO En-Jun GU Xiao-Fu SUN Ya-Guang YIN Hong-Xi WU Qiong LIU Lei ZHU Ming-Chang ZHANG Wan-Zhong 《中国化学》2008,26(11):2133-2136
A novel coordination polymer, [Mn(PDC)H2O]n (1) (H2PDC=pyridine-2,3-dicarboxylic acid), has been hydrothermally synthesized and characterized by elemental analysis, IR and single crystal X-ray diffraction. X-ray single crystal structural analyses revealed that two-dimensional frameworks were formed, and further assembled into a three-dimensional supramolecular structure bridged by PDC ligands. Moreover, the magnetic study of complex 1 shows weak antiferromagnetic interaction between the neighboring Mn(II) centers within the chains and even weak ferromagnetic interactions between the Mn(II) centers in different chains. 相似文献
996.
FuShengWANG LiYanPENG YuZHAO QinShiZHAO KunGU HanDongSUN 《中国化学快报》2004,15(3):307-308
A new taxoid, 2-deacetyl-2α, 14β-dihydroxybaccatin Ⅳ (1), was isolated from the leaves and branches of Taxus chinensis together with the known compound baccatin Ⅳ (2). The structure of the new compound was elucidated by spectroscopic techniques. The detailed ^13C NMR assignments of baccatin Ⅳ are reported for the first time. 相似文献
997.
Direct Electrochemistry of Catalase on Single Wall Carbon Nanotubes Modified Glassy Carbon Electrode
QiangZHAO LunHuiGUAN ZhenNanGU QianKunZHUANG 《中国化学快报》2005,16(4):501-504
Direct electrochemistry of catalase (Ct) has been studied on single wall carbon nanotubes (SWNTs) modified glassy carbon (GC) electrode. A pair of well-defined nearly reversible redox peaks is given at -0.48 V (vs. SCE) in 0.1 mol/L phosphate solution (pH 7.0).The peak current in cyclic voltammogram is proportional to the scan rate. The peak potential of catalase is shifted to more negative value when the pH increases. Catalase can adsorb on the SWNTs modified electrode. 相似文献
998.
Hui-Feng WANG Fei HUANG Zhen GU Zheng-Li HU Yi-Lun YING Bing-Yong YAN Yi-Tao LONG 《分析化学》2018,46(6):843-850
To achieve fast and accurate analysis of weak current signal of nanopore-based single molecule detection, an online data process based on adaptive threshold algorithm with data buffering technique and finite impulse response filtering was designed. A software system based on the data process was developed for online recognition and analysis of nanopore events during nanopore experiment. To testify the performance of the algorithm and software system, ideal signals with different noise level (20–100 pA) were generated at bandwidth ranging from 3 kHz to 100 kHz. The result showed that this software system was stable at different bandwidths and sampling rates and could be used in analyzing the signals at high noise. The proposed software system was further applied to aerolysin nanopore experiment for detection of poly(dA)4 molecules. The results showed that the data process system could be applied in real nanopore recording experiment with high accuracy and speed. 相似文献
999.
建立了一种同时测定动物源提取物中肌肽(Carnosine)和鹅肌肽(Anserine)含量的超高效液相色谱-电喷雾串联三重四极杆质谱(UHPLC-ESI-MS/MS)分析方法。采用超高效液相分离系统,借助Inertsil Amide HP色谱柱(2. 1 mm×100 mm,3μm)以0. 1%乙酸水溶液-乙腈为流动相,梯度洗脱分离,利用峰面积外标法定量。经过优化,肌肽和鹅肌肽在1. 95~500μg/L质量浓度范围内与峰面积呈良好的线性关系,相关系数(r)均大于0. 998。肌肽和鹅肌肽的检出限分别为0. 12、0. 47μg/L。以低浓度低聚肽原料为基质,在低、中、高3个加标浓度下,肌肽的回收率为99. 3%~109%,相对标准偏差(RSD,n=6)为0. 98%~1. 1%;鹅肌肽的回收率为100%~113%,RSD为1. 0%~1. 1%。该法前处理简单、快速,重现性好,准确度高,适用于动物源食物提取物中肌肽和鹅肌肽的同时快速检测。 相似文献
1000.
IntroductionThe abstraction reaction between CH,SiH, and H plays an important role in siliconcontaining species and has been the subject of many experimental studies'-', but it hasnot been studied with the variational transition state theory. In this paper, the dynamics ofthe title reaction is investigated by using POLYRATE7.8 program obtained from Truhlar'.The theoretical rate constants for the title reaction are obtained over a wide range oftemperature 298- 1 700 K.Theory and Methods'… 相似文献