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292.
Recently,we reported that deoxyribo-oligonucleotides could induce single chained cationic surfactant aggregation to form vesicles.In this paper,we will present that ribo-oligonucleotides can also induce vesicle formation,and compared with deoxyribo-oligonucleotides,ribo-oligonucleotides exhibit a higher inductive efficiency. 相似文献
293.
Enantiomeric separation of six antihistamine agents was first systematically investigated on a cellulose-based chiral stationary phase (CSP), that is, cellulose tris-(3,5-dimethyl phenyl carbamate) (Chiralcel OD-RH), under the reversed-phase mode. Orphenadrine, meclizine, terfenadine, dioxopromethazine, and carbinoxamine enantiomers were completely separated under the optimized mobile phase conditions with resolutions of 5.02, 1.93, 1.68, 1.67, and 1.54, respectively. Mequitazine was partially separated with a resolution of 0.77. The influences of type and concentration of buffer salt, the pH of buffer solution, and the type and ratio of organic modifier on the chiral separation were evaluated and optimized. For a better insight into the enantiorecognition mechanisms, molecular docking was carried out via the Autodock software. The lowest binding energy and the optimal conformations of the analytes/CSP complexes were supplied, and the mechanisms of chiral recognition were determined. According to the results, the key interactions for the chiral recognition of these six analytes on CDMPC were π–π interactions, hydrophobic interactions, hydrogen bond interactions, and some special interactions. 相似文献
294.
Ming Xia Prof. Miriding Mutailipu Fuming Li Prof. Zhihua Yang Prof. Shilie Pan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(38):9753-9757
Herein, a new congruently melting mixed-anion compound Cs4B4O3F10 has been characterized as the first fluorooxoborate with [BF4] involving heteroanionic units. Compound Cs4B4O3F10 possesses two highly fluorinated anionic clusters and therefore its formula can be expressed as Cs3(B3O3F6) ⋅ Cs(BF4). The influence of [BF4] units on micro-symmetry and structural evolution was discussed based on the parent compound. More importantly, Cs4B4O3F10 shows the lowest melting point among all the available borates and thus sets a new record for such system. This work is of great significance to enrich and tailor the structure of borates using perfluorinated [BF4] units. 相似文献
295.
Zhou Yan Bing Xia Ming Hua Qiu Ding Li Sheng Hong Xi Xu 《Biomedical chromatography : BMC》2013,27(11):1560-1567
A rapid and reliable method was established for simultaneous determination of main triterpenoids in Ganoderma lucidum spores using ultra‐high‐performance liquid chromatography coupled with triple quadrupole mass spectrometry (UPLC‐TQ‐MS). The established method was validated in terms of linearity, sensitivity, precision, accuracy and stability, and was successfully applied to determine the contents of 10 main triterpenoids in different batches of G. lucidum spores. The analysis results showed that moderate levels of triterpenoids were found in G. lucidum spores. In addition, a MS full scan with a daughter ion scan experiment was performed to identify the potential derivatives of triterpenoids present in G. lucidum spores. As a result, a total of 22 triterpenoids from different G. lucidum spores were unequivocally or tentatively identified via comparisons with authentic standards and literatures. This method provides both qualitative and quantitative results without the need for repetitive UPLC‐MS analyses, thereby increasing efficiency and productivity, making it suitable for high‐throughput applications. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
296.
Yang Yuchuan Wang Jing Liu Wei Deng Hao Zhao Peng Liao Wei Wang Guanquan Wei Hongyuan Zhuo Liangang Yang Xia 《Journal of Radioanalytical and Nuclear Chemistry》2021,330(3):997-1005
Journal of Radioanalytical and Nuclear Chemistry - Death receptor 5 (DR5) is overexpressed in many tumors. Combination of the anti-DR5 antibody with radionuclides such as lutetium-177 (177Lu) could... 相似文献
297.
Xia Jingwen King Alistair W. T. Kilpeläinen Ilkka Aseyev Vladimir 《Cellulose (London, England)》2021,28(17):10921-10938
Cellulose - Cellulose is an historical polymer, for which its processing possibilities have been limited by the absence of a melting point and insolubility in all non-derivatizing molecular... 相似文献
298.
299.
Asymmetric Michael Addition of Aldimino Esters with Chalcones Catalyzed by Silver/Xing‐Phos: Mechanism‐Oriented Divergent Synthesis of Chiral Pyrrolines
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Xing‐Feng Bai Dr. Li Li Dr. Zheng Xu Dr. Zhan‐Jiang Zheng Prof. Dr. Chun‐Gu Xia Dr. Yu‐Ming Cui Prof. Dr. Li‐Wen Xu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(30):10399-10404
The mechanism‐oriented reaction design for the divergent synthesis of chiral molecules from simple starting materials is highly desirable. In this work, aromatic amide‐derived nonbiarylatropisomer/silver (silver/Xing‐Phos) complex was used to catalyze the Michael addition of glycine aldimino esters to chalcones and successfully applied to the subsequent cyclocondensation to afford substituted cis‐Δ(1)‐pyrroline derivatives with up to 98 % ee. Besides the inherent performance of the chiral Ag/Xing‐Phos catalyst system, it was found that the workup of such reactions played an important role for the stereoselective construction of stereodivergent Δ(1)‐pyrrolines, in which an epimerization of the cis‐Δ(1)‐pyrrolines to the trans‐isomers during was revealed. 相似文献
300.
Dimerization of Colloidal Particles through Controlled Aggregation for Enhanced Properties and Applications
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Devising syntheses capable of precisely manipulating matter on the nanoscale is central to many areas of research. The underlying motivation is fueled by the fact that at the nanometer scale, the property has a strong correlation with the structure. One such nanostructure that has accrued much attention is the dimer—a structure composed of two colloidal particles separated by a small gap. This Focus Review discusses how colloidal stability can be strategically manipulated to induce dimerization, together with effective purification steps to further improve yields. We conclude the article by providing representative examples for how dimers composed of plasmonic nanoparticles leads to structures with tunable optical properties and strong electric near‐fields, ideal for application in surface‐enhanced Raman spectroscopy. 相似文献