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941.
Mizuk R Abe K Abe K Aihara H Akatsu M Asano Y Aulchenko V Aushev T Bakich AM Balagura V Ban Y Banerjee S Bedny I Bitenc U Bizjak I Blyth S Bondar A Bozek A Bracko M Brodzicka J Browder TE Chao Y Chen A Cheon BG Chistov R Choi SK Choi Y Chuvikov A Cole S Dalseno J Danilov M Dash M Dragic J Drutskoy A Eidelman S Fratina S Gabyshev N Garmash A Gershon T Gokhroo G Haba J Hastings NC Hayasaka K Hayashii H Hazumi M Hokuue T Hoshi Y Hou S Hou WS Hsiung YB Iijima T Imoto A Inami K Ishikawa A Itoh R 《Physical review letters》2005,94(12):122002
We report the observation of an isotriplet of excited charmed baryons, decaying into Lambda(+)(c)pi(-), Lambda(+)(c)pi(0), and Lambda(+)(c)pi(+). We measure the mass differences M(Lambda(+)(c)pi)-M(Lambda(+)(c)) and widths to be 515.4(+3.2+2.1)(-3.1-6.0) MeV/c(2), 61(+18+22)(-13-13) MeV for the neutral state; 505.4(+5.8+12.4)(-4.6-2.0) MeV/c(2), 62(+37+52)(-23-38) MeV for the charged state; and 514.5(+3.4+2.8)(-3.1-4.9) MeV/c(2), 75(+18+12)(-13-11) MeV for the doubly charged state, where the uncertainties are statistical and systematic, respectively. These results are obtained from a 281 fb(-1) data sample collected with the Belle detector near the Upsilon(4S) resonance, at the KEKB asymmetric energy e(+)e(-) collider. 相似文献
942.
Zhang J Abe K Abe K Abe T Aihara H Asano Y Aulchenko V Aushev T Aziz T Bahinipati S Bakich AM Bay A Bedny I Bitenc U Bizjak I Blyth S Bondar A Bozek A Bracko M Browder TE Chang P Chao Y Chen KF Cheon BG Chistov R Choi SK Choi Y Chuvikov A Danilov M Dash M Dong LY Dragic J Drutskoy A Eidelman S Eiges V Enari Y Fratina S Gabyshev N Garmash A Gershon T Gokhroo G Golob B Hayashii H Hazumi M Higuchi T Hinz L Hokuue T Hoshi Y Hou WS Hsiung YB Iijima T Imoto A Inami K Ishikawa A Ishino H Itoh R 《Physical review letters》2005,94(3):031801
We report a measurement of the branching fraction for the decay B+ --> rho(+) pi(0) based on a 140 fb(-1) data sample collected with the Belle detector at the KEKB asymmetric e(+)e(-) collider. We measure the branching fraction B(B(+) --> rho(+)pi(0)) = (13.2 +/- 2.3(stat)(+1.4)(-1.9)(syst)) x 10(-6), and the CP-violating asymmetry A(CP)(B-/+ -->rho(-/+)pi(0))=0.06 +/- 0.17(stat)(+0.04)(-0.05)(syst). 相似文献
943.
Dynamic pH junction technique for on-line preconcentration of peptides in capillary electrophoresis 总被引:1,自引:0,他引:1
A method based on the presence of a dynamic pH junction within the capillary to induce band narrowing for enhanced detection sensitivity for some peptides is presented. This technique is predicated on a sharp reduction in an analyte's migration velocity following a reversal of its electrophoretic direction from the acidic sample zone to the basic BGS zone. Larger-than-usual injection volumes of samples in relatively high-conductivity matrices were enabled, without degrading peak shape, resolution and efficiency. The size of the original sample plug was reduced by as much as 38-fold, and improvement in detector response in terms of peak height by as much as 124-fold was obtained. The effects of pH and concentration of the sample matrix, and the length of sample injection on the efficiency of the technique are discussed. 相似文献
944.
Absolute cross sections for the quenching of Cd(3P1) and Cd(3P0) by acetylene, ethylene, propene, cis-2-butene and four fluoroethylenes have been determined by a phase-shift method. It was found that acetylene and olefins quench the triplet cadmium at almost gas-kinetic encounter, while the quenching rates for fluoroethylenes were found to decrease with the increase in the number of substituted fluorine atoms. It was also observed that these molecules do not cause intramultiplet mixing between Cd(3P1) and Cd(3P0). The causes of the decrease of the reactivities of fluoroethylenes are discussed. 相似文献
945.
Dr. M. Ueda Dr. T. Urabata Dr. A. Katayama Dr. N. Kuroki 《Colloid and polymer science》1979,257(9):973-976
Summary The critical micelle concentrations (cmc) of non-ionic surfactants in water and in aqueous urea with or without hexahydric alcohols, sorbitol and inositol, were determined. In water the cmc's of the surfactants were decreased by the addition of the hexahydric alcohols. In addition, there was a remarkable difference in the decreasing ability between these two hexahydric alcohols. Inositol decreased the cmc's more markedly than sorbitol. In aqueous urea the effect of these hexahydric alcohols on the cmc's and the difference in the decreasing ability between the two alcohols were less than those in water. These results were explained in terms of the effect of the hexahydric alcohols on the structure of water.
With 5 figures and 2 tables 相似文献
Zusammenfassung Es wurde die kritische Mizellbildungskonzentration nichtionogener Tenside in Wasser sowie in wäßrigen Harnstofflösungen mit und ohne Zusatz von Inosit und Sorbitol bestimmt. In Wasser wird die cmc bei Zusatz der hexahydrischen Alkohole vermindert; Inosit wirkt dabei stärker als Sorbit. In wässrigen Harnstofflösungen ist der Einfluß auf die cmc und der Unterschied zwischen den zwei Alkoholen geringer als in Wasser. Die Ergebnisse werden über die Beeinflussung der Struktur des Wassers durch die Alkohole gedeutet.
With 5 figures and 2 tables 相似文献
946.
W. Manchot H. Gall J. König O. Scherer H. R. Ambler T. C. Sutton T. J. Drakeley H. Nicol P. Schuftan A. T. Larson C. W. Whittaker A. B. Lamb W. E. Vail P. Lebeau P. Marmasse J. I. Graham C. de la Condamine A. Thau J. Thorbun L. Wein H. Lent H. Kast H. Selle M. Nicloux S. H. Katz G. Wittig J. E. Underwood A. Krogh P. Brandt Rehberg Shigeru Nishi J. Johnston A. C. Walker 《Analytical and bioanalytical chemistry》1928,75(1-2):39-46
947.
We observed hillock formation during metalorganic molecular beam epitaxy (MOMBE) of InGaAs on a mesa-grooved (100) GaAs substrate. Hillocks were formed under specific growth conditions and comprised mostly InAs. The distribution of hillocks formed in InGaAs MOMBE using trimethylindium (TMIn) and metal Ga depended strongly on the widths of mesa-grooves; the density decreased with decreasing width and hillocks were hardly observed on the ridges. The hillock density also varied, depending on the off-angle of the substrate from the (100) plane. This indicates that the observed anomalous distribution of InGaAs hillocks was caused by both the formation of facets and a vicinal tilted surface near the edge of mesa-grooves, due to the growth of a GaAs buffer layer on a patterned substrate. 相似文献
948.
Motoharu Imai Kenichi Yaoita Yoshinori Katayama Jian-Qiang Chen Kazuhiko Tsuji 《Journal of Non》1992,150(1-3):49-52
The phase transitions from the quenched high-pressure phase, including amorphous state, have been investigated for crystalline silicon and germanium at various pressures. X-ray diffraction patterns have been measured at pressures up to 15 GPa and temperatures down to 90 K by an energy-dispersive method using synchrotron radiation and a diamond anvil cell. The quenched β-Sn phase undergoes an amorphous phase transition when heated at 1.5 GPa for c-Si and 2.0 GPa for c-Ge. On the other hand, the quenched β-Sn phase transforms into a metastable crystalline phase when heated at higher pressures. The phase behavior is discussed in relation to the pressure dependence of the height of potential barrier between the β-Sb and amorphous phases and that between the β-Sn and metastable phases. The coordination number for the pressure-induced amorphous germanium, obtained through amorphization from the quenched high-pressure phase, is estimated to be about 4. 相似文献
949.
Bortoletto D Goldberg M Horwitz N Jain V Mestayer MD Moneti GC Sharma V Shipsey IP Skwarnicki T Thulasidas M Csorna SE Letson T Alexander J Artuso M Bebek C Berkelman K Cassel DG Cheu E Coffman DM Crawford G DeWire JW Drell PS Ehrlich R Galik RS Gittelman B Gray SW Halling AM Hartill DL Heltsley BK Kandaswamy J Katayama N Kreinick DL Lewis JD Mistry NB Mueller J Namjoshi R Nandi S Nordberg E O'Grady C Peterson D Pisharody M Riley D Sapper M Silverman A Stone S Worden H Worris M Sadoff AJ 《Physical review letters》1990,64(18):2117-2120
950.