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排序方式: 共有1343条查询结果,搜索用时 15 毫秒
1.
Miao Wang Xinluo Zhao Masato Ohkohchi Yoshinori Ando 《Fullerenes, Nanotubes and Carbon Nanostructures》1996,4(5):1027-1039
Carbon nanotubes prepared by de arc discharge of graphite electrodes in He and CH4 gas took markedly different morphology. Thick nanotubes embellished with many carbon nanoparticles were obtained by evaporation under high CH4 gas pressure and high arc current. Thin and long carbon nanotubes were obtained under a CH4 gas pressure of 50Torr and an arc current of 20A for the anode with a diameter of 6mm. 相似文献
2.
Rinji Akada Yoshirou Shimizu Yuji Matsushita Miho Kawahata Hisashi Hoshida Yoshinori Nishizawa 《Yeast (Chichester, England)》2002,19(1):17-28
Drug-resistance markers for yeast transformation are useful because they can be applied to strains without auxotrophic mutations. However, they are susceptible to technical difficulties, namely lower transformation efficiency and the appearance of drug-resistant mutants without the marker. To avoid these problems, we have constructed a phosphoglycerate kinase (PGK) promoter-driven YAP1 expression cassette, called PGKp-YAP1. Yeast cells containing PGKp-YAP1 were resistant to cycloheximide, a protein synthesis inhibitor, and also to cerulenin, a fatty acid synthesis inhibitor, but not to other drugs tested. The transformation efficiency of PGKp-YAP1 using cerulenin selection was comparable to that using a URA3 auxotrophic marker when low concentrations of cerulenin were used. Non-transformed drug-resistant colonies did appear on the low-concentration cerulenin plates. However, these non-transformed colonies could easily be identified, based on their cycloheximide sensitivity and/or their resistance to aureobasidin A to which the transformants were sensitive. Therefore, the dual drug resistance of PGKp-YAP1 could be used as an effective selection for PGKp-YAP1 recipient cells. The PGKp-YAP1 marker was used to disrupt the LYS2 gene and to transform an industrial yeast strain, indicating that this marker can be used for efficient and reliable gene manipulations in any Saccharomyces cerevisiae strain. 相似文献
3.
Yoshinori Nakazawa 《Advanced Performance Materials》1995,2(4):369-384
MITI has actively done R&D on industrial technology for waste and reclamation and so there are many research items from small scale to large scale. However, Ecofactory and researches on recycling of metallic materials are introduced here. Ecofactory was proposed by the Mechanical Engineering Laboratory and is now at the stage of the Leading Research, a new research scheme in AISt. Researches on recycling of metallic materials are being done with subsidy. Those researches should contribute to both the preservatin of the global environment and effective recycling of waste materials.Abbreviations AIST
Agency of Industrial Science and Technology
- MITI
Ministry of International Trade and Industry
- NEDO
New Energy and Industrial Technology Development Organization 相似文献
4.
New research and development needs for the drying of ceramics are prooosed. The researches on the ceramic drying are briefly reviewed and the role of the drying in the ceramic production process iS summarized. The drying must deal with molded materials and the problem is of significant difference from another drying with particulate materials. It means that the drying must be performed with keeping the molded feature and the insufficient completion of drying and the careless operation influence directly on the product quality The importnance of the R & D on the heat and moisture transfer. shrinking mechanism. the deformation behavior and the strain-stress formation in the molded clay issuggested. The subjects are also pointed out for the further improvement of the ceramic drying process and the precise design of molding with high quality. 相似文献
5.
T Hanaoka A Sawaumi K Ohtsuka K Nakata K Taguchi O Shimojima 《Canadian Metallurgical Quarterly》1996,9(3):257-264
The nature of the events whereby the reactive intermediates resulting from the bioactivation of bromobenzene and furosemide induce hepatotoxicity is unknown. To examine a role for disturbances in intracellular calcium homeostasis, secondary to a depletion in cellular reduced glutathione (GSH) and reduced protein thiols (PSHs), isolated mouse hepatocytes were exposed to cytotoxic concentrations of bromobenzene or furosemide. Cytosolic calcium concentration, as well as thiol status, was determined. The incubation of hepatocytes with 3.0 mM bromobenzene, and subsequent additions (1.2 mM) of the agent every hour, resulted in significant GSH depletion. The loss of plasma membrane integrity at 1.5 h preceded both a rise in the cytosolic Ca2+ concentration and depletion of total PSH content. Furosemide (1.0 mM) produced a 70% depletion in cellular GSH content in isolated hepatocytes. The initiation of cell damage occurred concurrently with both a rise in the cytosolic Ca2+ concentration and a depletion of total PSH content 4 h following furosemide addition. Since the increase in cytosolic Ca2+ did not precede cytotoxicity, these results do not support an initiating role for Ca2+ deregulation in bromobenzene and furosemide hepatotoxicities. In addition, depletion of PSH content did not correlate with bromobenzene- or furosemide-induced cytotoxicity. 相似文献
6.
A molecular orbital approach to materials design has recently made great progress. This approach is based on the electronic structure calculations by the DV-Xα cluster method. In this paper recent progress in this approachis reviewed. In particular 相似文献
7.
An improved T -Ω method that can analyze magnetic fields produced not only by eddy currents but also by magnetizing currents is proposed. The method is applied to the analysis of 3-D eddy-current models with holes. The usefulness of the method is investigated by comparing calculated results with measured results and with results obtained by the A -Φ method. The T -Ω method has the advantage that the CPU time can be considerably reduced when most of the analyzed region is current-free and the eddy current flows two-dimensionally. The method is especially effective when the shape of the winding is simple and the distribution of magnetizing current is known beforehand. It is not effective when most of the analyzed region is current-carrying 相似文献
8.
Yamada T. Nakata Y. Hasegawa J. Amano N. Shibayama A. Sasago M. Matsuo N. Yabu T. Matsumoto S. Okada S. Inoue M. 《Solid-State Circuits, IEEE Journal of》1991,26(11):1506-1510
A 64-Mb dynamic RAM (DRAM) has been developed with a meshed power line (MPL) and a quasi-distributed sense-amplifier driver (qDSAD) scheme. It realizes high speed, t RAS=50 ns (typical) at V cc=3.3 V, and 16-b input/output (I/O). This MPL+qDSAD scheme can reduce sensing delay caused by the metal layer resistance. Furthermore, to suppress crosstalk noise, a V SS shield peripheral layout scheme has been introduced, which also widens power line widths. This 64-Mb DRAM was fabricated with 0.4-μm CMOS technology using KrF excimer laser lithography. A newly developed memory cell structure, the tunnel-shaped stacked-capacitor cell (TSSC), was adapted to this 64-Mb DRAM 相似文献
9.
Tetsuya Murai Yoshiharu Sato Germano Resconi Michinori Nakata 《Electronic Notes in Theoretical Computer Science》2003,82(4):186
The concept of granular computing is applied to Aristotle's categorical syllogism. Such kind of reasoning is called granular reasoning in this paper. For the purpose, two operations called zooming in & out are introduced to reconstruct granules of possible worlds. 相似文献
10.
This paper is to review the works on strains and suesses in materials during drying.The strains and suesses are caused when temperature and moisture gradients are generated in mterials whose volume changes with heating and moisture removal. In such materials. failure and irregular deformion may be generated which affect considerably the qudity of the products after drying. In the first part. modeling procedure is introduced for the analysis of the strain-stress behavior in elaslic. viscous and visccelastic materials combined with heat and moisture transfer. An overview of the works on swains and stresses and drying characteristics are presented for malerials such as porous media. clay. sol-gels. agricultural products and foods in the second part. There are some materials that show both elasticity of the solid phase and viscosity of the fluid phase ( water or solvena∥ or viscoelasticiry. The suesses are often correlated with a suction pressure of fluids in pores and the flow rate is based on Dacy's equation for the elastic and viscous tnedia and a kind of viscoelastic media. The general canstitulive equalions. for suains and svesses are often analyzed with the stain behavior given by a function of moisturr for some media ai well. The emohasis is on the inuoduclion of comprehensive criteria for undersunding the problems of strain and stress development in materials subjected to drying. 相似文献