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991.
992.
993.
Hideto Tanoue Shinichiro Oke Hirofumi Takikawa Yushi Hasegawa Masao Kumagai Takeshi Ishikawa 《Applied Surface Science》2009,255(17):7780-7785
A new technique to etch a substrate as a pre-treatment prior to functional film deposition was developed using a filtered vacuum arc plasma. An Ar-dominated plasma beam was generated from filtered carbon arc plasma by introducing appropriate flow rate of Ar gas in a T-shape filtered arc deposition (T-FAD) system. The radiation spectra emitted from the filtered plasma beam in front of a substrate table were measured. The substrate was etched by the Ar-dominated plasma beam. The principal results are summarized as follows. At a high flow rate of Ar gas (50 ml/min), when the bias was applied to the substrate, the plasma was attracted toward the substrate table and the substrate was well etched without film formation on the substrate. Super hard alloy (WC), bearing steel (SUJ2), and Si wafer were etched by the Ar-dominated plasma beam. The etching rate was dependent on the kind of substrate. The roughness of the substrate increased, when the etching rate was high. A pulse bias etched the substrate without roughening the substrate surface excessively. 相似文献
994.
Tajima O Hayashii H Hazumi M Inami K Iwasaki Y Uehara S Abe K Adachi I Aihara H Anipko D Aulchenko V Bakich AM Barberio E Bedny I Belous K Bitenc U Bizjak I Bondar A Bozek A Bracko M Browder TE Chang MC Chen A Chen KF Chen WT Cheon BG Chistov R Choi Y Choi YK Cole S Dalseno J Danilov M Dash M Drutskoy A Eidelman S Fratina S Gabyshev N Gershon T Go A Gokhroo G Ha H Haba J Hayasaka K Heffernan D Hokuue T Hoshi Y Hou S Hou WS Iijima T Ikado K Ishikawa A Ishino H Itoh R Iwasaki M Kang JH Kataoka SU 《Physical review letters》2007,98(13):132001
We report results of a search for the invisible decay of the Upsilon(1S) via the Upsilon(3S)-->pi+ pi- Upsilon(1S) transition using a data sample of 2.9 fb-1 at the Upsilon(3S) resonance. The data were collected with the Belle detector at the KEKB asymmetric-energy e+ e- collider. No signal is found, and an upper limit for the branching fraction at the 90% confidence level is determined to be B(Upsilon(1S)-->invisible)<2.5 x 10(-3). 相似文献
995.
Lin SW Chang P Abe K Abe K Adachi I Aihara H Anipko D Arinstein K Aulchenko V Aushev T Aziz T Bakich AM Barberio E Bay A Bedny I Belous K Bitenc U Bizjak I Blyth S Bondar A Bozek A Bracko M Chao Y Chen A Chen KF Chen WT Cheon BG Chistov R Choi SK Choi Y Choi YK Dalseno J Dash M Dragic J Eidelman S Fratina S Gabyshev N Gershon T Go A Gokhroo G Golob B Ha H Haba J Hara T Hayasaka K Hayashii H Hazumi M Heffernan D Hoshi Y Hou S Hou WS Hsiung YB Iijima T Ikado K Imoto A Inami K Ishikawa A Ishino H 《Physical review letters》2007,98(18):181804
Using 449x10(6) BB[over ] pairs collected with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider, we observe clear signals for B(+)-->K[over ](0)K(+) and B(0)-->K[over ](0)K(0) decays with 5.3sigma and 6.0sigma significance, respectively. We measure the branching fractions B(B(+)-->K[over ](0)K(+))=(1.22(-0.28-0.16)(+0.32+0.13))x10(-6) and B(B(0)-->K[over ](0)K(0))=(0.87(-0.20)(+0.25)+/-0.09)x10(-6), and partial-rate asymmetries A(CP)(B(+)-->K[over ](0)K(+))=0.13(-0.24)(+0.23)+/-0.02 and A(CP)(B(0)-->K[over ](0)K(0))=-0.58(-0.66)(+0.73)+/-0.04. From a simultaneous fit, we also obtain B(B(+)-->K(0)pi(+))=(22.8(-0.7)(+0.8)+/-1.3)x10(-6) and A(CP)(B(+)-->K(0)pi(+))=0.03+/-0.03+/-0.01. The first and second error in the branching fractions and the partial-rate asymmetries are statistical and systematic, respectively. No signal is observed for B(0)-->K(+)K(-) decays, and for this branching fraction, we set an upper limit of 4.1x10(-7) at the 90% confidence level. 相似文献
996.
Fratina S Abe K Abe K Adachi I Aihara H Anipko D Arinstein K Aushev T Bakich AM Barberio E Bay A Belous K Bitenc U Bizjak I Bondar A Bozek A Bracko M Brodzicka J Browder TE Chang MC Chang P Chao Y Chen A Chen KF Chen WT Cheon BG Chistov R Choi Y Choi YK Cole S Dalseno J Dash M Drutskoy A Eidelman S Go A Golob B Gorisek A Ha H Haba J Hara K Hazumi M Heffernan D Hokuue T Hoshi Y Hou WS Iijima T Inami K Ishikawa A Ishino H Itoh R Iwasaki M Iwasaki Y Kaji H Kang JH Katayama N Kawai H Kawasaki T 《Physical review letters》2007,98(22):221802
We report measurements of the branching fraction and CP violation parameters in B(0)-->D+ D- decays. The results are based on a data sample that contains 535 x 10(6) BB pairs collected at the Upsilon(4S) resonance, with the Belle detector at the KEKB asymmetric-energy e+e- collider. We obtain [1.97+/-0.20(stat) +/- 0.20(syst)] x 10(-4) for the branching fraction of B0-->D+D-. The measured values of the CP violation parameters are S=-1.13+/-0.37+/-0.09, A=0.91+/-0.23+/-0.06, where the first error is statistical and the second is systematic. We find evidence of CP violation in B0-->D+D- at the 4.1sigma confidence level. While the value of S is consistent with expectations from other measurements, the value of the parameter A favors large direct CP violation at the 3.2sigma confidence level, in contradiction to standard model expectations. 相似文献
997.
Zhang LM Zhang ZP Adachi I Aihara H Aulchenko V Aushev T Bakich AM Balagura V Barberio E Bay A Belous K Bitenc U Bondar A Bozek A Bracko M Brodzicka J Browder TE Chang P Chao Y Chen A Chen KF Chen WT Cheon BG Chiang CC Cho IS Choi Y Choi YK Dalseno J Danilov M Dash M Drutskoy A Eidelman S Epifanov D Fratina S Gabyshev N Gokhroo G Golob B Ha H Haba J Hara T Hastings NC Hayasaka K Hayashii H Hazumi M Heffernan D Hokuue T Hoshi Y Hou WS Hsiung YB Hyun HJ Iijima T Ikado K Inami K Ishikawa A 《Physical review letters》2007,99(13):131803
We report a measurement of D0-D(0) mixing parameters in D(0) --> K(s)(0) pi(+) pi(-) decays using a time-dependent Dalitz-plot analysis. We first assume CP conservation and subsequently allow for CP violation. The results are based on 540 fb(-1) of data accumulated with the Belle detector at the KEKB e(+)e(-) collider. Assuming negligible CP violation, we measure the mixing parameters x = (0.80 +/- 0.29(-0.07-0.14)(+0.09+0.10))% and y = (0.33+/-0.24(-0.12-0.08)(+0.08+0.06))%, where the errors are statistical, experimental systematic, and systematic due to the Dalitz decay model, respectively. Allowing for CP violation, we obtain the CP-violating parameters |q / p| = 0.86(-0.29-0.03)(+0.30+0.06) +/- 0.08 and arg(q/p) = (-14(-18-3-4)(+16+5+2)) degrees . 相似文献
998.
Katayama M Takamatsu K Kaneko S Miyaji K Ishikawa H Matsuda Y 《Journal of separation science》2007,30(14):2279-2285
Improvement of the sensitivity and specificity of a simultaneous stress-free screening method for catechol estrogens as a potential prostate cancer marker in urine has been accomplished by HPLC with a diamond-electrode electrochemical detector and a fluorescence detector. Since taking urine samples generates less stress (or pain) than the drawing of blood, the method can readily be applied to almost any patient, and will also assist in improving the sensitivity and specificity of the prostatic specific antigen test. Catechol estrogens (2-hydroxyestrone, 4-hydroxyestrone, 2-methoxyestrone, 2-hydroxyestradiol, 4-hydroxyestradiol, 2-methoxyestradiol, and 2-hydroxyestriol) and estrogens (estrone, estradiol, estriol) were separated on an Inertsil ODS-II column with acetonitrile-potassium dihydrogen phosphate (pH 3.0). The diamond-electrode electrochemical detector used had the great advantage of being a maintenance-free system, and could sequentially analyze hundreds of samples. Fluorescence detection improved the sensitivity 10-500 times (e. g., the LOD of 2-hydroxyestriol was improved 250 times) compared to previous electrochemical detection reports, and dual detection improved peak identification in the urine samples. The proposed method was applied to the simultaneous determination of catechol estrogens in spiked urine in a preliminary study on estrogens and PSA values in biopsy and prostate cancer patients. 相似文献
999.
B3LYP-based density functional theory (DFT) calculations with effective core potentials (ECPs) (LANL2DZ) on M and 6-311+G(2d) all-electron basis function sets on C and O are used to interpret the symmetry characteristic vibrational absorption patterns of CO ligands in the "naked" coordinatively unsaturated transition-metal carbonyls M(CO)n-1 (M = Cr, Mo, and W; n = 4-6) observed by a time-resolved infrared absorption spectroscopy after the UV pulse laser photolysis of M(CO)6 in the gas phase. The UV photolysis results can be reasonably explained by the trends in the calculated bond dissociation enthalpies of M(CO)n-1-CO for group 6 metal carbonyls. M(CO)n-1 produced through one CO elimination from M(CO)n is found out to keep its parent skeleton, resulting in the structure with symmetry of C4v for M(CO)5, C2v for M(CO)4, and C3v for M(CO)3. 相似文献
1000.
Nakashima K Maki M Ishikawa F Yoshikawa T Gong YK Miyajima T 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2007,67(3-4):930-935
Binding of pyrene (PyH) and its derivatives to humic acid (HA) has been studied by fluorescence spectroscopy. The nature of the interaction between HA and pyrene derivatives are extensively investigated by employing three derivatives ranging from anionic to cationic compounds: 1-pyrenebutylic acid (PyA), 1-pyrenemethanol (PyM), and 1-pyrenebutyltrimethylammonium bromide (PyB). Binding constants between HA and PyX (X=H, A, M, B) are obtained by steady-state fluorescence quenching techniques, and it is found that PyB has a markedly large binding constant among the pyrene family. This is attributed to a strong electrostatic interaction between cationic PyB and anionic HA. The result suggests that an electrostatic interaction plays a dominant role in binding of pyrenes to humic acid. The importance of electrostatic interaction was also confirmed by a salt effect on the binding constant. Influence of collisional quenching on the binding constant, which causes overestimation of the binding constant, was examined by time-resolved fluorescence spectroscopy as well as temperature effect in steady-state fluorescence measurements. It is elucidated that collisional quenching does not much bring overestimation into the binding constants. 相似文献