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151.
152.
Han Bing Teng 《中国化学快报》2010,21(7):810-812
<正>A novel organophosphorus compound containing the structure of bothβ-amino acid andβ-aminophosphonate is designed and synthesized.Arbuzov reaction with P(OEt)_3,the N-Boc protected iodide 3 cannot provide the desired product but 2-oxazolidinone 4 because of the neighboring-group participation of the Boc moiety.To avoid the intramolecular participation of the carbamates,the Ts protecting group is employed and the Ts-protected iodide 5 affords the target product successfully. 相似文献
153.
Guangyuan Teng Lijing Gao Guomin Xiao Hu Liu Jianhua Lv 《Applied biochemistry and biotechnology》2010,162(6):1725-1736
This paper discusses the synthesis of biodiesel catalyzed by solid base of K2CO3/HT using Jatropha curcas oil as feedstock. Mg–Al hydrotalcite was prepared using co-precipitation methods, in which the molar ratio of Mg to Al was 3:1. After calcined at 600 °C for 3 h, the Mg–Al hydrotalcite and K2CO3 were grinded and mixed according to certain mass ratios, in which some water was added. The mixture was dried at 65 °C, and after that it was calcined at 600 °C for 3 h. Then, this Mg–Al hydrotalcite loaded with potassium carbonate was obtained and used as catalyst in the experiments. Analyses of XRD and SEM characterizations for catalyst showed the metal oxides formed in the process of calcination brought about excellent catalysis effect. In order to achieve the optimal technical reaction condition, five impact factors were also investigated in the experiments, which were mass ratio, molar ratio, reaction temperature, catalyst amount and reaction time. Under the best condition, the biodiesel yield could reach up to 96%. 相似文献
154.
Yunhua Yu Qing Yang Donghua Teng Xiaoping Yang Seungkon Ryu 《Electrochemistry communications》2010,12(9):1187-1190
Reticular tin nanoparticle-dispersed carbon (Sn/C) nanofibers were fabricated by stabilization of electrospun SnCl4/PAN composite fibers and subsequent carbonization at different temperatures. These Sn/C composite nanofibers used as anode materials for rechargeable lithium-ion batteries (LIBs) show that the Sn/C nanofibers at 700 and 850 °C present much higher charge (785.8 and 811 mA h g?1) and discharge (1211.7 and 993 mA h g?1) capacities than those at 550 and 1000 °C and the as-received CNFs at 850 °C, corresponding to coulombic efficiencies of 64.9% and 81.7%, respectively. The superior electrochemical properties of the intriguing Sn/C nanofibers indicate a promising application in high performance Li-ion batteries. 相似文献
155.
The first example of a polystyrene bearing two distinct reagent groups has been prepared. This phosphine and amine functionalized material was used in one-pot Wittig reactions with an aldehyde and either an α-halo-ester, -ketone, or -amide. Due to the heterogeneous nature of the polymer, the desired alkene product of these reactions could be isolated in excellent yield in essentially pure form after only filtration and solvent removal. 相似文献
156.
The lipid membrane plays crucial roles in countless biologic processes, ranging from cell motility, endo- and exocytosis,
and cell division to protein aggregation and trafficking. To gain a molecular insight in these biologic processes, the recently
developed mesoscale simulation technique, dissipative particle dynamics (DPD) simulation, has become an invaluable tool. By
providing a brief survey of existing atomistic and popular coarse-grained models used today in studying the dynamics (including
vesicle formation and (protein-mediated) vesicle fusion) and phase behavior of lipid bilayers, this review illustrates how
mesoscopic DPD models can be used to obtain a better understanding of these biologic processes currently inaccessible to atomistic
and most coarse-grained models. 相似文献
157.
Diphenyl diamine-based phosphonyl imines attached by the N-isopropyl group in the auxiliary have been synthesized in good yields under convenient reaction conditions. These new chiral N-phosphonyl imines can react with glycine enolate smoothly to give chiral α-β diamino esters in good yields (72%–90%) and up to excellent diastereoselectivity (>99:1 dr). By treatment with HBr, the chiral auxiliary can be readily removed. The absolute structure has been unambiguously determined by converting a product to a known sample. 相似文献
158.
159.
To identify and eliminate the inner filter effects (IFEs), prepositive and side cells containing absorbents are fixed beside
the fluorescer contained cell. In this way, excitation and emission lights can be quenched by primary and secondary outer
filter effects respectively, depending on absorbent concentration and cell length. Herein the quenching of emission fluorescence
caused by IFEs can be equally reduced by outer filter effects (OFEs) and the interference of IFEs was eliminated. This approach
was experimentally used for identifying the interaction mode and mechanism between BSA and nanoAg. Results showed that the
quenching of BSA fluorescence and synchronous fluorescence mainly attributes to IFEs, instead of static/dynamic fluorescent
quenching. In view of the above, the elimination of the interference of IFEs by the design of OFEs plays an important part
in the precise application of fluorescence detector. 相似文献
160.