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排序方式: 共有276条查询结果,搜索用时 187 毫秒
1.
Takayuki Yamanaka Hideki Fukano Ken Tsuzuki Munehisa Tamura Ryuzo Iga Matsuyuki Ogasawara Yasuhiro Kondo Tadashi Saitoh 《光学学报》2003,23(Z1)
A comprehensive analysis of multi-quantum-well electroabsorption modulators buried with semi-insulating (SI)-InP is presented. We quantitatively demonstrate that suppression of Zn diffusion into the burying and optical core layers plays a key role in high-speed and high-extinction operation. 相似文献
2.
To develop a sealed-type nickel-metal hydride battery for use in portable equipment or in electric vehicles, investigations
were conducted on negative electrodes using AB5-type hydrogen storage alloy and positive electrodes. For the cycle life performance of the battery, alkaline treatment of
the alloy and the substitution of more than 50% to the alloy with Co were effective. For the positive electrode, zinc as a
solid solution in the nickel positive electrode obviously prevented γ-NiOOH from being formed in the charging process of β-Ni(OH)2 and suppressed the migration of the electrolyte solution in the separator to the active material of the positive electrode.
Also, hydrophobic treatment of the surface of the alloy was effective to prevent the elevation of the battery internal pressure
of the battery in high rate charge. 相似文献
3.
Y Kusumoto M Goto H Tajima K Nakata R Furukawa A Satoh K Kawahara N Ishii T Munehisa T Koji 《Radioisotopes》1984,33(10):686-690
To determine the diagnostic value of anti-HBc IgM in acute viral hepatitis or chronic liver disease B, Anti-HBc IgM was measured by a RIA and an ELISA in 32 patients with acute hepatitis (4 with type A, 15 with type B and 13 with type non A non B), 18 patients with chronic hepatitis and 19 patients with liver cirrhosis. In acute hepatitis B, anti-HBc IgM (both RIA and ELISA) was positive in 14(93%) of 15 patients and its cut-off index value was very high. However, anti-HBc IgM was always negative in one patient with typical course of type B. In 1 of 4 patients with acute hepatitis A and 2 of 13 with non A non B, anti-HBc IgM (RIA and/or ELISA) was positive. These 3 patients were positive for anti-HBs at the onset of disease, so we could not made the diagnosis of acute hepatitis B. Anti-HBc IgM was positive in 21(51%) of 37 patients with HBsAg-positive chronic liver disease by RIA and in 11 (30%) by ELISA, and its cut-off index value was relatively low. These results suggest that when adequate cut-off index value is established, anti-HBc analysis is useful for differentiating recent and current infections from remote infections. 相似文献
4.
M Shimizu S Horie S Terashima H Ueno T Hayashi M Arisawa S Suzuki M Yoshizaki N Morita 《Chemical & pharmaceutical bulletin》1989,37(9):2531-2532
Aldose reductase (AR) inhibitory activity-directed fractionation of the 70% ethanolic extract of Para-parai mí, Phyllanthus niruri, has led to the isolation of three active components, ellagic acid (1), brevifolin carboxylic acid (4) and ethyl brevifolin carboxylate (5). Among them, 1 showed the highest inhibitory activity, being about 6 times more potent than quercitrin, which is a known natural inhibitor of AR. 相似文献
5.
Reinosuke Hayakawa Toshio Nishi Kunio Arisawa Yasaku Wada 《Journal of Polymer Science.Polymer Physics》1967,5(1):165-177
Thermal expansion and dielectric relaxation of polyacrylonitrile were measured in the temperature range from ?75 to 152°C. at frequencies from 30 cps to 3 Mc./sec. The thermal expansion curve and the temperature dependence of logarithmic relaxation time both show an inflection at 85°C. An x-ray study by Bohn reveals that this inflection comes from the thermal expansion of the paracrystalline phase of this polymer, and consequently the transition at 85°C. and the associated relaxation are ascribed to molecular motion in the paracrystalline phase. The relaxation strength increases with increasing temperature above this point. The transition is caused by freezing of the bending vibration of chains whereas the relaxation results from rotational vibration. The length of segments in this phase is roughly estimated to be ca. 100 A. by comparing the observed relaxation strength with the theory developed on the basis of the above considerations. 相似文献
6.
Phenols are ethynylated at the ortho position with silylated chloroethyne in the presence of a catalytic amount of GaCl3 and lithium phenoxide. The lithium salt is essential for the catalysis, and addition of 2,6-di(tert-butyl)-4-methylpyridine inhibits desilylation and hydration of the products. The reaction can be applied to various substituted phenols giving the ortho-ethynylated products in high yields, and the turnover numbers based on GaCl3 are between 8 and 10. The reaction mechanism involves addition of in situ formed phenoxygallium to the haloethyne followed by the elimination of GaCl3. 相似文献
7.
Abulencia A Adelman J Affolder T Akimoto T Albrow MG Ambrose D Amerio S Amidei D Anastassov A Anikeev K Annovi A Antos J Aoki M Apollinari G Arguin JF Arisawa T Artikov A Ashmanskas W Attal A Azfar F Azzi-Bacchetta P Azzurri P Bacchetta N Badgett W Barbaro-Galtieri A Barnes VE Barnett BA Baroiant S Bartsch V Bauer G Bedeschi F Behari S Belforte S Bellettini G Bellinger J Belloni A Benjamin D Beretvas A Beringer J Berry T Bhatti A Binkley M Bisello D Blair RE Blocker C Blumenfeld B Bocci A 《Physical review letters》2007,98(13):132002
We present an analysis of angular distributions and correlations of the X(3872) particle in the exclusive decay mode X(3872)-->J/psipi+ pi- with J/psi-->mu+ mu-. We use 780 pb-1 of data from pp[over ] collisions at sqrt[s]=1.96 TeV collected with the CDF II detector at the Fermilab Tevatron. We derive constraints on spin, parity, and charge conjugation parity of the X(3872) particle by comparing measured angular distributions of the decay products with predictions for different J(PC) hypotheses. The assignments J(PC)=1++ and 2-+ are the only ones consistent with the data. 相似文献
8.
Aaltonen T Abulencia A Adelman J Affolder T Akimoto T Albrow MG Ambrose D Amerio S Amidei D Anastassov A Anikeev K Annovi A Antos J Aoki M Apollinari G Arguin JF Arisawa T Artikov A Ashmanskas W Attal A Azfar F Azzi-Bacchetta P Azzurri P Bacchetta N Badgett W Barbaro-Galtieri A Barnes VE Barnett BA Baroiant S Bartsch V Bauer G Bedeschi F Behari S Belforte S Bellettini G Bellinger J Belloni A Benjamin D Beretvas A Beringer J Berry T Bhatti A Binkley M Bisello D Blair RE Blocker C Blumenfeld B 《Physical review letters》2007,98(14):142001
We present a measurement of the top-quark mass Mtop in the all-hadronic decay channel tt-->W+bW-b-->q1q2bq3q4b. The analysis is performed using 310 pb-1 of sqrt[s]=1.96 TeV pp[over ] collisions collected with the CDF II detector using a multijet trigger. The mass measurement is based on an event-by-event likelihood which depends on both the sample purity and the value of the top-quark mass, using 90 possible jet-to-parton assignments in the six-jet final state. The joint likelihood of 290 selected events yields a value of Mtop=177.1+/-4.9(stat)+/-4.7(syst) GeV/c2. 相似文献
9.
Affolder T Akimoto H Akopian A Albrow MG Amaral P Amidei D Anikeev K Antos J Apollinari G Arisawa T Artikov A Asakawa T Ashmanskas W Azfar F Azzi-Bacchetta P Bacchetta N Bachacou H Bailey S de Barbaro P Barbaro-Galtieri A Barnes VE Barnett BA Baroiant S Barone M Battle C Bauer G Bedeschi F Belforte S Bell WH Bellettini G Bellinger J Benjamin D Bensinger J Beretvas A Berge JP Berryhill J Bhatti A Binkley M Bisello D Bishai M Blair RE Blocker C Bloom K Blumenfeld B Blusk SR Bocci A Bodek A 《Physical review letters》2002,88(7):071806
We present the first general search for new heavy particles, X, which decay via X --> WZ0 --> e(nu)+jj as a function of M(X) and Gamma(X) in pp collisions at square root[s] = 1.8 TeV. No evidence is found for production of X in 110 pb(-1) of data collected by the Collider Detector at Fermilab. General cross section limits are set at the 95% C.L. as a function of mass and width of the new particle. The results are further interpreted as mass limits on the production of new heavy charged vector bosons which decay via W' --> WZ0 in an extended gauge model as a function of the width, Gamma(W'), and mixing factor between the W' and the standard model W bosons. 相似文献
10.
Acosta D Affolder T Albrow MG Ambrose D Amidei D Anikeev K Antos J Apollinari G Arisawa T Artikov A Ashmanskas W Azfar F Azzi-Bacchetta P Bacchetta N Bachacou H Badgett W Barbaro-Galtieri A Barnes VE Barnett BA Baroiant S Barone M Bauer G Bedeschi F Behari S Belforte S Bell WH Bellettini G Bellinger J Benjamin D Beretvas A Bhatti A Binkley M Bisello D Bishai M Blair RE Blocker C Bloom K Blumenfeld B Bocci A Bodek A Bolla G Bolshov A Bortoletto D Boudreau J Bromberg C Brubaker E Budagov J 《Physical review letters》2005,94(17):171802
We report the first largely model independent measurement of charged particle multiplicities in quark and gluon jets, Nq and Ng, produced at the Fermilab Tevatron in pp collisions with a center-of-mass energy of 1.8 TeV and recorded by the Collider Detector at Fermilab. The measurements are made for jets with average energies of 41 and 53 GeV by counting charged particle tracks in cones with opening angles of theta(c) = 0.28, 0.36, and 0.47 rad around the jet axis. The corresponding jet hardness Q = Ejet theta c varies in the range from 12 to 25 GeV. At Q = 19.2 GeV, the ratio of multiplicities r = Ng/Nq is found to be 1.64+/-0.17, where statistical and systematic uncertainties are added in quadrature. The results are in agreement with resummed perturbative QCD calculations. 相似文献