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991.
992.
M K LIM Z ZHANG 《厦门大学学报(自然科学版)》2002,(Z1)
This paper introduces a multi-agent system which i nt egrates process planning and production scheduling, in order to increase the fle xibility of manufacturing systems in coping with rapid changes in dynamic market and dealing with internal uncertainties such as machine breakdown or resources shortage. This system consists of various autonomous agents, each of which has t he capability of communicating with one another and making decisions based on it s knowledge and if necessary on information provided ... 相似文献
993.
Z J PEI X J XIN 《厦门大学学报(自然科学版)》2002,(Z1)
Silicon wafers are the most widely used substrates for semiconductors. The falling price of silicon wafers has created tremendous pressure on silicon wafer manufacturers to develop cost-effective manufacturing processes. A critical issue in wafer production is the waviness induced by wire sawing. If this waviness is not removed, it will affect wafer flatness and semiconductor performance. In practice, both lapping and grinding have been used to flatten wire-sawn wafers. Although grinding is not as effective... 相似文献
994.
1 Results Less-flammability is one of the most valuable properties of ionic liquids (ILs) comprised of perfluoroanions such as BF-4,TFSI-([(CF3SO2)2N]-).Recently,such a unique liquid has been expected to use as an electrolyte in order to improve thermal stability and longevity of a lithium secondary battery,which have been increasingly required for an application especially to an electric vehicle and a hybrid car.We previously reported that PI13[TFSI] (PI13: N-methyl-N-propylpiperidinium) could be used ... 相似文献
995.
996.
One-dimensional (1D) nanoscale materials (nanotubles, nanorods, nanowires and nanobelts or nanoribbons and so on) are currently of a matter of much interest. Due to their unique properties in electronics, magnetics, optics, and mechanics, they can be used to design and fabricate nanosensors, switches, nanolasers, transistors and other nanodevices[1]. In order to obtain desired one-dimensional materials, many techniques and methods have been developed[2]. 相似文献
997.
998.
The incorporation of 35S-cysteine and 3H-glutamic acid was studied in mouse hepatic and renal metallothionein and in testicular cadmium-binding protein of similar molecular weight. Preferential incorporation of 35S-cysteine over 3H-glutamic acid was observed not only in hepatic and renal metallothionein, but also in testicular cadmium-binding protein. When the antigenic reactivity of these proteins was compared, all three proteins reacted with the metallothionein antibody. These similarities suggest that the low molecular weight testicular cadmium-binding protein is apparently metallothionein. 相似文献
999.
Summary The telomere of the 2R arm of the salivary gland chromosomes ofD. auraria exhibits a definite toroidal structure in routine squashed preparations, stained either by propionic orcein-carmine or by fluorescent dyes. There is evidence that a band (or bands) of region 68 (possibly homologous to that ofD. melanogaster) of the 3L chromosome arm also exhibits a toroidal structure. These toroids are associated with heterochromatin, but it is not certain that they are themselves heterochromatic.Acknowledgments. This work was supported by a grant from Volkswagenwerk-Stiftung to C.D.K. The outstanding technical assistance of Ms G. Karamanlidis is acknowledged. 相似文献
1000.
The interaction of ligands with the mouse macrophage Fc receptor which binds IgG2b and IgG1 immune complexes (FcR gamma 2b/gamma 1) triggers phagocytosis and secretion of various mediators of inflammation. FcR gamma 2b/gamma 1 has been purified using a monoclonal anti-FcR antibody, 2.4G2, and seems to be an integral membrane glycoprotein of molecular weight (Mr) 47,000-60,000 (ref. 6). Monoclonal antibody 2.4G2 is suitable as a tool for functional studies of FcR because it binds to a functional site of the receptor and induces cellular responses that are normally associated with the occupied receptor. We reported previously that binding of ligands to the macrophage FcR resulted in Na+/K+ ion fluxes through the plasma membrane, and that similar ion fluxes were observed in proteoliposomes containing reconstituted FcR. We have now incorporated FcR into planar lipid bilayers and report here that FcR gamma 2b/gamma 1 forms ligand-dependent cation-selective ion channels, with a conductance of 60 pS in 1 M KCl and an average open channel lifetime of 250 ms. The conductance decays to baseline levels within a few minutes. These results suggest a receptor-ionophore model for the signalling of phagocytosis and inflammatory responses. 相似文献