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Wang Xinglei Guo Hangxu Wang Fan Tan Tianshe Wu Hang Zhang Hongxia 《Journal of Radioanalytical and Nuclear Chemistry》2020,324(3):1151-1165
Journal of Radioanalytical and Nuclear Chemistry - In this study, the halloysite nanotubes was characterized and the adsorption of Th(IV) and U(VI) on halloysite nanotubes was investigated as a... 相似文献
3.
Monoester‐diterpenoid alkaloids are the main bioactive components of Sini decoction, which is a well‐known traditional Chinese medicine formula for the treatment of myocardial infarction (MI) and heart failure in China. In this work, an ultra‐high‐performance liquid chromatography–mass spectrometry combined with microdialysis method was successfully established and applied for investigating for the first time comparative plasma pharmacokinetics of three monoester‐diterpenoid alkaloids (benzoylmesaconitine, benzoylaconitine and benzoylhypacoitine) in normal and MI rats after oral administration of Sini decoction. The statistical results of pharmacokinetic parameters demonstrated that benzoylmesaconitine, benzoylaconitine and benzoylhypacoitine showed lower peak concentration, longer half‐life, smaller area under the concentration–time curve, slower clearance, time to peak concentration and mean residence time in MI rats than in normal rats (p < 0.05), which indicated that monoester‐diterpenoid alkaloids exhibited lower systemic exposure and slower elimination in the MI rats. The results provided the experimental basis for understanding the metabolic fate and therapeutic effects of Sini decoction. 相似文献
4.
Nonlinear Dynamics - In this paper, we mainly propose a chaotic secure communication scheme which is based on the synchronization of double-layered and multiple complex dynamical networks. Compared... 相似文献
5.
Wei Shyang Tan Ting‐Yin Lee Sheng‐Fang Tseng Ying‐Feng Hsu Masanori Ebina Tetsuya Taketsugu Shing‐Jong Huang Jye‐Shane Yang 《中国化学会会志》2019,66(9):1141-1156
Despite the long history of polyaniline chemistry, backbone‐substituted polyanilines are limited. Here, we report the synthesis of pentiptycene‐incorporated polyanilines through acidic aniline oxidative polymerization with three pentiptycene derivatives, TA, DA, and TP, as nucleate additives. The reactivity of TA > DA ? TP, as evidenced by structural and property analysis of the corresponding polyaniline products, demonstrates a radical coupling mechanism and the formation of Dewar π‐complex intermediates for the chain propagation. In addition, the iptycene substituent effect on enhancing the electrochemical stability and charge storage capability of polyaniline are discussed with a clip model, namely, the threading of neighboring polyaniline chains through the U‐ and V‐shaped cavities of pentiptycene restricts lateral motions of the polymer chains and promotes interchain conductivity. Density function theory (DFT) calculations suggest a larger clipping effect for the U versus V cavities. Both the conclusion of a terminal planar p‐phenylenediamine (ppda) group being the key component of an effective nucleate and the concept of interchain clipping for enhanced electrochemical performance should facilitate the design and synthesis of novel polyanilines for electronic applications. 相似文献
6.
Agar microspheres were prepared by water–oil emulsification and cross‐linked under alkaline condition. The thermoresponsive hydrophobic copolymer, poly(N‐isopropylacrylamide‐co‐lauryl methacrylate‐co‐acrylamide), was grafted on the agar microspheres via atom transfer radical polymerization. The agar microspheres grafted with copolymers were characterized by light microphotography, elemental analysis, Fourier transform infrared spectroscopy, scanning electron microscopy, and X‐ray photoelectron spectroscopy. The chain lengths and hydrophobic monomer ratio of the grafting linear polymer had significant effects on the hydrophobicity and adsorption capacity of agar microspheres at different temperatures. The thermoresponsive microspheres were used for separation of proteins and showed binding and release behavior by change of temperatures without change in mobile phase composition. Thus, we suggest thermoresponsive agar microspheres as an alternative separation media for all‐aqueous bioseparations. 相似文献
7.
Wenhao Ren Xin Tan Wanfeng Yang Chen Jia Shumao Xu Kaixue Wang Sean C. Smith Chuan Zhao 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(21):7046-7050
Polynary single‐atom structures can combine the advantages of homogeneous and heterogeneous catalysts while providing synergistic functions based on different molecules and their interfaces. However, the fabrication and identification of such an active‐site prototype remain elusive. Here we report isolated diatomic Ni‐Fe sites anchored on nitrogenated carbon as an efficient electrocatalyst for CO2 reduction. The catalyst exhibits high selectivity with CO Faradaic efficiency above 90 % over a wide potential range from ?0.5 to ?0.9 V (98 % at ?0.7 V), and robust durability, retaining 99 % of its initial selectivity after 30 hours of electrolysis. Density functional theory studies reveal that the neighboring Ni‐Fe centers not only function in synergy to decrease the reaction barrier for the formation of COOH* and desorption of CO, but also undergo distinct structural evolution into a CO‐adsorbed moiety upon CO2 uptake. 相似文献
8.
Designs, Codes and Cryptography - For a long time, the literature has demonstrated that designs and codes are exciting topics for combinatorics and coding theory. Linear codes and t-designs are, in... 相似文献
9.
This review examines the most recent electrochemical developments for nitrate, nitrite and ammonium detection for on-site water monitoring. There remains a high demand for effective field-based detection of the dissolved inorganic nitrogen (DIN) analytes to aid in mitigating nitrogen loading. Electrochemical approaches show increasing potential to fill this role as advancements in nanotechnology continually improve analytical performance and on-site applicability. However, translating these improvements into the field still faces the resonating challenges of reaching analytical proficiency (selectivity, sensitivity, robustness, stability), practical end-user functionality, minimal matrix interferences and cost effectiveness. Herein, we elaborate on these challenges via a critical evaluation of current studies and examine how realistic the prospects of on-site nitrate, nitrite and ammonium are. We also present recommendations in addressing these gaps to conclude the review. 相似文献
10.
The separation efficiency of charge carriers determines the analytical sensitivity of the paper-based photoelectrochemical sensor. Herein, the Lewis base modification strategy is proposed to promote the carrier separation through an in-situ ion exchange method. Firstly, three-dimensional paper-based hierarchically TiO2 (PHT) arrays are prepared with the one-step hydrothermal method. With the aid of Lewis base, the photo-induced charge separation efficiency and the photocurrent signal are obviously increased. Ultimately, sensitive sensing of prostate specific antigen (PSA) is achieved and the linear range is 1 pg/mL–100 ng/mL with the detection limitation of 0.3 pg/mL. 相似文献