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101.
102.
This paper focuses on the identification problem of Wiener nonlinear systems with non-uniform sampling. The mathematical model for the Wiener nonlinear system is established from the non-uniformly sampled input–output data. In order to solve the identification problem of the Wiener nonlinear system with the unmeasurable variables in the information vector, the gradient-based iterative algorithm is presented by replacing the unmeasurable variables with their corresponding iterative estimates. Finally, the simulation results indicate that the proposed algorithm is effective. 相似文献
103.
A purge and trap technique to capture volatile compounds combined with comprehensive two‐dimensional gas chromatography/time‐of‐flight mass spectrometry to investigate the effect of sulfur‐fumigation on Radix Angelicae Dahuricae 下载免费PDF全文
Gang Cao Qinglin Li Jida Zhang Hao Cai Baochang Cai 《Biomedical chromatography : BMC》2014,28(9):1167-1172
Sulfur‐fumigation is known to reduce volatile compounds that are the main active components in herbs used in herbal medicine. We investigated changes in chemical composition between sun‐dried and sulfur‐fumigated Radix Angelicae Dahuricae using a purge and trap technique to capture volatile compounds, and two‐dimensional gas chromatography/time‐of‐flight mass spectrometry for identification. Using sun‐dried Radix Angelicae Dahuricae samples as a reference, the results showed that 73 volatile compounds, including 12 sulfide compounds, were found to be present only in sulfur‐fumigated samples. Furthermore, 32 volatile compounds that were found in sun‐dried Radix Angelicae Dahuricae samples disappeared after sulfur‐fumigation. The proposed method can be applied to accurately discriminate sulfur‐fumigated Radix Angelicae Dahuricae from different commercial sources. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
104.
A copper-catalyzed synthesis of methyl esters from aromatic aldehydes in the presence of tert-butyl hydrogen peroxide (TBHP) was developed via a radical reaction mechanism. TBHP acts not only as an efficient oxidant, but also as a green methyl source in such transformation. Moreover, this method could also be efficiently extended to the methyl esterification of benzylic alcohols. 相似文献
105.
The enhancement of teleportation fidelity by weak measurement or quantum measurement reversal is investigated. One qubit of a maximally entangled state undergoes the amplitude damping, and the subsequent application of weak measurement or quantum measurement reversal could improve the teleportation fidelity beyond the classical region. The improvement could not be attributed to the increasing of entanglement, quantum discord, classical correlation or total correlation. We declare that it should be owed to the probabilistic nature of the method. 相似文献
106.
107.
Hong Chengming Wang Xiaojun Pan Zhigang Zhang Yifan 《Journal of Thermal Analysis and Calorimetry》2015,120(1):427-438
Journal of Thermal Analysis and Calorimetry - The saturated aliphatic binary carboxylic acid, including succinic acid, adipic acid and sebacic acid, were used to improve the curing process of... 相似文献
108.
109.
Dr. N. Kodiah Beyeh Dr. Fangfang Pan Dr. Sandip Bhowmik Toni Mäkelä Prof. Robin H. A. Ras Acad. Prof. Kari Rissanen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(4):1355-1361
N‐Alkyl ammonium resorcinarene salts (NARYs, Y=triflate, picrate, nitrate, trifluoroacetates and NARBr) as tetravalent receptors, are shown to have a strong affinity for chlorides. The high affinity for chlorides was confirmed from a multitude of exchange experiments in solution (NMR and UV/Vis), gas phase (mass spectrometry), and solid‐state (X‐ray crystallography). A new tetra‐iodide resorcinarene salt (NARI) was isolated and fully characterized from exchange experiments in the solid‐state. Competition experiments with a known monovalent bis‐urea receptor ( 5 ) with strong affinity for chloride, reveals these receptors to have a much higher affinity for the first two chlorides, a similar affinity as 5 for the third chloride, and lower affinity for the fourth chloride. The receptors affinity toward chloride follows the trend K1?K2?K3≈ 5 >K4, with Ka=5011 m ?1 for 5 in 9:1 CDCl3/[D6]DMSO. 相似文献
110.
Dr. Malin Li Dr. Yu Gao Dr. Nan Chen Dr. Xing Meng Prof. Chunzhong Wang Dr. Yaoqing Zhang Dr. Dong Zhang Prof. Yingjin Wei Dr. Fei Du Prof. Gang Chen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(32):11405-11412
Cu3V2O8 nanoparticles with particle sizes of 40–50 nm have been prepared by the co‐precipitation method. The Cu3V2O8 electrode delivers a discharge capacity of 462 mA h g?1 for the first 10 cycles and then the specific capacity, surprisingly, increases to 773 mA h g?1 after 50 cycles, possibly as a result of extra lithium interfacial storage through the reversible formation/decomposition of a solid electrolyte interface (SEI) film. In addition, the electrode shows good rate capability with discharge capacities of 218 mA h g?1 under current densities of 1000 mA g?1. Moreover, the lithium storage mechanism for Cu3V2O8 nanoparticles is explained on the basis of ex situ X‐ray diffraction data and high‐resolution transmission electron microscopy analyses at different charge/discharge depths. It was evidenced that Cu3V2O8 decomposes into copper metal and Li3VO4 on being initially discharged to 0.01 V, and the Li3VO4 is then likely to act as the host for lithium ions in subsequent cycles by means of the intercalation mechanism. Such an “in situ” compositing phenomenon during the electrochemical processes is novel and provides a very useful insight into the design of new anode materials for application in lithium‐ion batteries. 相似文献