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391.
A facile and green preparation of high surface area activated carbons with mixed
microporosity and mesoporosity from durian shell waste is reported in this work. The pore
structure and surface chemistry of the parent carbon were modified by the combination of
ultrasonication and microwave irradiation techniques. The effects of temperature and time in the
ultrasonication treatment and power output and time in the microwave irradiation were studied.
The electrochemical performance of carbon electrodes for supercapacitors was tested by cyclic
voltammeter (CV) and galvanostatic charge–discharge. The results show that the capacitive energy
storage of electrodes is critically dependent on the microporosity and surface chemistry of activated
carbons. The highest electrode capacitance in this work was 103.6 F/g that prepared from activated
carbon modified at an ultrasonication temperature of 323.15 K for 10 min and microwave power
output of 900 W for 10 min. 相似文献
392.
393.
Crystal structure of an HIV-binding recombinant fragment of human CD4 总被引:68,自引:0,他引:68
S E Ryu P D Kwong A Truneh T G Porter J Arthos M Rosenberg X P Dai N H Xuong R Axel R W Sweet 《Nature》1990,348(6300):419-426
CD4 glycoprotein on the surface of T cells helps in the immune response and is the receptor for HIV infection. The structure of a soluble fragment of CD4 determined at 2.3 A resolution reveals that the molecule has two intimately associated immunoglobulin-like domains. Residues implicated in HIV recognition by analysis of mutants and antibody binding are salient features in domain D1. Domain D2 is distinguished by a variation on the beta-strand topologies of antibody domains and by an intra-sheet disulphide bridge. 相似文献
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398.
Novel regulation and function of Src tyrosine kinase 总被引:4,自引:0,他引:4
Src tyrosine kinase is a critical signal transducer that modulates a wide variety of cellular functions. Misregulation of
Src leads to cell transformation and cancer. Heterotrimeric guanine-nucleotide-binding proteins (G proteins) are another group
of signaling molecules that transduce signals from cell-surface receptors to generate physiological responses. Recently, it
was discovered that Gαs and Gαi could directly stimulate Src family tyrosine kinase activity. This novel regulation of Src
tyrosine kinase by G proteins provides insights into the adenylyl cyclase-independent signaling mechanisms involved in ligand-induced
receptor desensitization, internalization and other physiological processes.
Received 17 August 2001; received after revision 22 October 2001; accepted 24 October 2001 相似文献
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Aberrant patterns of X chromosome inactivation in bovine clones 总被引:24,自引:0,他引:24