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101.
Abe F Akimoto H Akopian A Albrow MG Amendolia SR Amidei D Antos J Anway-Wiese C Aota S Apollinari G Asakawa T Ashmanskas W Atac M Auchincloss P Azfar F Azzi-Bacchetta P Bacchetta N Badgett W Bagdasarov S Bailey MW Bao J de Barbaro P Barbaro-Galtieri A Barnes VE Barnett BA Barzi E Bauer G Baumann T Bedeschi F Behrends S Belforte S Bellettini G Bellinger J Benjamin D Benlloch J Bensinger J Benton D Beretvas A Berge JP Berryhill J Bertolucci S Bhatti A Biery K Binkley M Bisello D Blair RE 《Physical review letters》1996,76(23):4307-4311
102.
103.
Abe F Albrow M Amidei D Anway-Wiese C Apollinari G Atac M Auchincloss P Azzi P Baden AR Bacchetta N Badgett W Bailey MW Bamberger A de Barbaro P Barbaro-Galtieri A Barnes VE Barnett BA Bauer G Baumann T Bedeschi F Behrends S Belforte S Bellettini G Bellinger J Benjamin D Benlloch J Bensinger J Beretvas A Berge JP Bertolucci S Biery K Bhadra S Binkley M Bisello D Blair R Blocker C Bodek A Bolognesi V Booth AW Boswell C Brandenburg G Brown D Buckley-Geer E Budd HS Busetto G Byon-Wagner A 《Physical review D: Particles and fields》1993,48(3):998-1008
104.
105.
Abe K Abt I Acton PD Agnew G Ash WW Aston D Bacchetta N Baird KG Baltay C Band HR Baranko G Bardon O Battiston R Bazarko AO Bean A Belcinski RJ Ben-David R Benvenuti AC Biasini M Bienz T Bilei GM Bisello D Blaylock G Bogart JR Bolton T Bower GR Brau JE Breidenbach M Bugg WM Burke D Burnett TH Burrows PN Busza W Calcaterra A Caldwell DO Calloway D Camanzi B Carpinelli M Carr J Cassell R Castaldi R Castro A Cavalli-Sforza M Chadwick GB Chen L Church E Claus R Cohn HO Coller JA Cook V Cotton R 《Physical review letters》1993,71(16):2528-2532
106.
Hirokazu Okuma Hitoshi Takahashi Shuichi Sekimukai Kouji Kawahara Ryoichi Akahoshi 《Analytica chimica acta》1991
An amperometric enzyme electrode for the determination of hypoxanthine in fish meat is described. The hypoxanthine sensor was prepared from xanthine oxidase immobilized by covalent binding to cellulose triacetate and a carbon paste electrode containing hydroxymethylferrocene. The xanthine oxidase membrane was retained behind a dialysis membrane at a carbon paste electrode. The sensor showed a current response to hypoxanthine due to the bioelectrocatalytic oxidation of hypoxanthine, in which hydroxymethyiferrocene served as an electron-transfer mediator. The limit of detection is 6 × 10?7 M, the relative standard deviation is 2.8% (n=28) and the response is linear up to 7 × 10?4 M. The sensor responded rapidly to a low hypoxanthine concentration (7 × 10?4 M), the steady-state current response being achieved in less than 1 min, and was stable for more than 30 days at 5 ° C. Results for tuna samples showed good agreement with the value determined by the conventional method. 相似文献
107.
The concise synthesis of Amaryllidaceae alkaloids, such as anhydrolycorinone, anhydrolycorin-7-one, assoanine, and oxoassoanine, which have a pyrrolophenanthridine skeleton, was achieved in moderate yield using the Pd-mediated biaryl coupling reaction of 1-(2-halobenzyl)-2,3-dihydroindole, which applied the regioselective C-H activation method with intramolecular coordination of the benzylamino group to Pd. 相似文献
108.
Sm2+-doped glasses in the system of Al2O3-SiO2 were prepared by sol-gel processing of metal alkoxides and reacting with H2 gas at 800°C. The hole burning properties of these glasses were investigated. The holes were burned in the 7F0 5D0 line of the Sm2+ ions using a DCM dye laser at 77 K. The hole depth increased with increasing the laser irradiation time, reaching up to 15% of the total intensity within a few hundred seconds. The hole width was 3 cm–1 full width at half maximum. Fluorescence line narrowing spectra of the 5D0 7 F1 transition were analyzed to study the local structure surrounding the Sm2+ ion. It is concluded that the Sm2+ ions are closely coordinated with nine oxygens of the AlO6 group in aluminosilicate glasses and that the addition of Al3+ ions into glass induces an increase in the coordination number of the Sm2+. 相似文献
109.
Two new acylated flavanone glycosides, (S)-eriodictyol 7-O-(6"-O-trans-p-coumaroyl)-beta-D-glucopyranoside (1) and (S)-eriodictyol 7-O-(6"-O-galloyl)-beta-D-glucopyranoside (2) were isolated from the leaves and branches of Phyllanthus emblica together with a new phenolic glycoside, 2-(2-methylbutyryl)phloroglucinol 1-O-(6"-O-beta-D-apiofuranosyl)-beta-D-glucopyranoside (3), as well as 22 known compounds. Their structures were determined by spectral and chemical methods. 相似文献
110.
The origin of Cotton effect shown by o-nitrobenzoyl esters is discussed. The Cotton effect observed for 1-(?)-methyl ester of 3-nitrophalic acid and 4-nitrohemimellitic acid (6 and 12), indicated that the favoured twisting direction of the nitrobenzene moiety is determined by the asymmetric menthyl group through the intervening carboxyl groups. This provides a new concept in conformational analysis of aromatic compounds. Extending the concept of conformational transmission to 2,2′-dinitrobipenhyl derivatives with known ab twisted nitrobenzene was related to the sign of the Cotton effect at 330 nm in accordance with the result of X-ray crystal analysis 1-(?)-menthyl 4-bromo-2-nitrobenzoate (1) 相似文献