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1.
The simplified expressions for the electromagnetic field of the near zone from the magnetic frill are derived. In these formulas,E_{rho} andH_{phi} are expressed as a single integration of the complete elliptical integrals of the first and second kinds. Furthermore the closed form ofE_{z} is obtained approximately. Their accuracy is checked numerically by comparing with Tsai's, and significant improvement in efficiencies is obtained. 相似文献
2.
Norikazu Nishiyama Tao Zheng Yusuke Yamane Yasuyuki Egashira Korekazu Ueyama 《Carbon》2005,43(2):269-274
Microporous carbons have been synthesized by the carbonization of cationic surfactant-resorcinol/formaldehyde (RF) composites, which were themselves formed by electrostatic organic-organic interaction. The porous structure produced by the decomposition of the surfactant plays an important role for the gasification of the RF polymer at higher temperatures. The pore size of the carbon prepared from tetrapropylammonium bromide (TPAB)-RF, cetyltrimethylammonium bromide (C16TAB)-RF and decyltrimethylammonium bromide (C10TAB)-RF mixtures can be estimated as 0.53 nm from the Horvath-Kawazoe method using N2 adsorption isotherms. Their pore size distributions were very narrow, showing that the microporous carbons derived from surfactant-RF mixture may have promise as adsorbents and membrane materials. 相似文献
3.
Masayuki Morita Ryo Arizono Nobuko Yoshimoto Minato Egashira 《Journal of Applied Electrochemistry》2014,44(4):447-453
The electrochemical activation process of the so-called “alkali-treated soft carbon” (ASC) has been examined in organic electrolyte solutions. SEM observation demonstrated that the edge plane of graphene structure of the ASC particle becomes rough after the activation, and XRD measurements indicated that the average lattice constant of graphene stacking in ASC increases after the activation process. Ex-situ 7Li NMR measurements proved that the insertion of cation (Li+) into the pore structure of ASC is associated with the activation process in the electrolyte dissolving Li salt. The pore-size distribution determined from N2-gas adsorption for ASC electrodes before and after the electrochemical activation indicates that the pore structure becomes developed after the electrochemical polarization, especially in the pore-diameter range of 2–10 nm. A schematic model of the activation process has been presented, which includes electrochemical insertion of ions into the inside of the ASC. 相似文献
4.
Kiyomi Ohmori Asuka Kamei Yuki Watanabe Keiko Abe 《International journal of molecular sciences》2022,23(6)
The Bhas 42 cell transformation assay (Bhas 42 CTA) is the first Organization for Economic Cooperation and Development (OECD)-certificated method used as a specific tool for the detection of the cell-transformation potential of tumor-promoting compounds, including non-genotoxic carcinogens (NGTxCs), as separate from genotoxic carcinogens. This assay offers the great advantage of enabling the phenotypic detection of oncotransformation. A key benefit of using the Bhas 42 CTA in the study of the cell-transformation mechanisms of tumor-promoting compounds, including non-genotoxic carcinogens, is that the cell-transformation potential of the chemical can be detected directly without treatment with a tumor-initiating compound since Bhas 42 cell line was established by transfecting the v-Ha-ras gene into a mouse fibroblast cloned cell line. Here, we analyzed the gene expression over time, using DNA microarrays, in Bhas 42 cells treated with the tumor-promoting compound 12-O-tetradecanoylphorbol-13-acetate (TPA), and NGTxC, with a total of three repeat experiments. This is the first paper to report on gene expression over time during the process of cell transformation with only a tumor-promoting compound. Pathways that were activated or inactivated during the process of cell transformation in the Bhas 42 cells treated with TPA were related not only directly to RAS but also to various pathways in the hallmarks of cancer. 相似文献
5.
Melt pool behaviour and the characteristics of the surrounding metal powder during selective laser melting (SLM) are captured using high-speed imaging, and the influence of the substrate temperature and the line building sequence on the formation of the built structure and the generation of spatter particles is experimentally investigated. The results indicate that the substrate temperature has a measurable effect on the formation of droplets and the generation of spatter particles, while the volume specific energy density of the process was the principal factor affecting the built structure. 相似文献
6.
Hitoshi Ushijima Makoto Egashira 《Journal of Materials Science: Materials in Electronics》1999,10(4):259-266
Reduction of cuprous chloride has been examined in various atmospheres, mostly at 600°C, to produce copper microfibers that can be applied as a filler for electromagnetic interference shielding and electron conductive paste composites. The reduction with hydrogen resulted in formation of a large amount of copper films, but fine particles and short filaments were obtained when carbon black was mixed into the raw material. The most promising copper microfibers with dimensions of several mm length and 1–10 m thickness could be produced with the system CuCl — C — H2O using argon as a carrier gas, where H2 and CO formed then probably reduced the vaporized CuCl molecules. Introduction of hydrogen gas into this system increased the yield of copper microfibers, though they became more bent, curved and kinked in shape. However, the morphology of the microfibers is still acceptable as a filler. 相似文献
7.
The influence of HCl, Cl2, Br2 and I2 on the vapor phase growth of carbon fibers from naphthalene was examined at 1100°C with the expectation of a promotive effect similar to H2S. However, these halogen additives were found not to catalyse but to inhibit the growth. Employment of 1-chloronaphthalene as the source material also resulted in the remarkable suppression of fiber formation. The fibers obtained in the presence of the halogens exhibited highly pockmarked surfaces, due to deposition of soot-like carbon. In addition, the deposition was preferential at the growing end of the fiber, so that the diameter became thick progressively from root to tip. From these observations, the inhibition of the fiber growth with halogens was attributed to the accelerated decomposition of naphthalene into soot-like carbon. 相似文献
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