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41.
Asner DM Athanas M Bliss DW Brower WS Masek G Paar HP Gronberg J Korte CM Kutschke R Menary S Morrison RJ Nakanishi S Nelson HN Nelson TK Qiao C Richman JD Roberts D Ryd A Tajima H Witherell MS Balest R Cho K Ford WT Lohner M Park H Rankin P Smith JG Alexander JP Bebek C Berger BE Berkelman K Bloom K Browder TE Cassel DG Cho HA Coffman DM Crowcroft DS Dickson M Drell PS Dumas DJ Ehrlich R Elia R Gaidarev P Garcia-Sciveres M Gittelman B Gray SW Hartill DL Heltsley BK Henderson S Jones CD 《Physical review D: Particles and fields》1996,53(3):1039-1050
42.
Bean A Gronberg J Kutschke R Menary S Morrison RJ Nelson H Richman J Tajima H Schmidt D Sperka D Witherell M Procario M Yang S Daoudi M Ford WT Johnson DR Lingel K Lohner M Rankin P Smith JG Alexander JP Bebek C Berkelman K Besson D Browder TE Cassel DG Coffman DM Drell PS Ehrlich R Galik RS Garcia-Sciveres M Geiser B Gittelman B Gray SW Hartill DL Heltsley BK Honscheid K Jones C Kandaswamy J Katayama N Kim PC Kreinick DL Ludwig GS Masui J Mevissen J Mistry NB Ng CR Nordberg E O'Grady C 《Physical review letters》1993,70(2):138-142
43.
Nanosecond fluorescence spectroscopy has been used to study the interaction of 2-anilinonaphthalene with polar solvent molecules which is shown to result in stoichiometric complex formation at low polar solvent concentrations. This is followed by reorientation of the solvent cage when the concentration of polar solvent is high. 相似文献
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Template Reaction of Bis(acetylacetonato)-dioxo-molybdenum(VI) with Benzoylhydrazone By reaction of bis(acetylacetonato)-dioxo-molybdenum(VI) with benzoylhydrazine benzoylhydrazido(2?)-acetylacetonebenzoylhydrazonato(2?)-oxo-molybdenum(VI) was formed beside another species. The compound was characterized by mass spectrometry and X-ray structural analysis. Crystallographic data see ?Inhaltsübersicht”?. 相似文献
48.
Tetraphenylphosphonium triiodotetrabromide [PPh4][I3Br4] is obtained by the reaction of tetraphenylphosphonium bromide with iodine monobromide. It is the first example of an iodine rich, seven-membered polybromide. [PPh4][I3Br4] crystallizes triclinic in the space group P1 with a = 10.947(1) A, b = 11.945(1) A, c = 12.896(1) A, alpha = 66.80(1) degrees, beta = 77.21(1) degrees, gamma = 85.73(1) degrees, and two formula units per unit cell. The final R indices [I > 4 sigma(I)] are R1 = 0.0362 and wR2 = 0.0944. 相似文献
49.
Aromatic ketones react with 3-mercapto-1,2-propanediol ( 1 ) in refluxing benzene under the catalytic influence of a sulfonic acid and with azeotropic removal of water to yield a mixture comprised predominantly of cis- and trans-2-alkyl-2-aryl-1,3-oxathiolane-5-methanols 7, accompanied by lesser amounts of cis- and trans-2-alkyl-2-aryl-1,3-dioxolane-4-methanethiols 8 (up to 30%). It was discovered that 8 is the kinetic product and is isomerized by 4-toluenesulfonic acid in hot benzene to the thermodynamically more stable 7 . Under these conditions, ortho- and α-substituted aromatic ketones tend to produce more of 8 , which can be attributed to steric hindrance encountered by the thiol as it attacks the ketone. Ketalizations of 1-aryl-2-(1H-imidazol-1-yl)-1- as well as 1-aryl-2-(1,H-1,2,4-triazol-1-yl)-1-ethanones by 1 fail under these conditions, even after 24 hours of reflux in toluene. However, 1-(4-chlorophenyl)-3-(1H-imidazol-1-yl)-1-propanone and 1-(4-bromophenyl)-4-(1H-imidazol-1-yl)-1-butanone are ketalized by 1 as expected. Interestingly, the reaction of 2-bromo-4′-chloroace-tophenone with 1 produces 1-(4-chlorophenyl)-2,8-dioxa-6-thiabicyclo[3.2.1]octane. Characterization of all isomers and separation of some diastereomers is described. Nuclear Overhauser enhancement experiments are utilized to establish the stereochemistry of 1,3-oxathiolanes. 相似文献
50.
Owens TM Ludwig BJ Fosnacht DR Bartolin JM Homann N Wells NJ Orr BG Banaszak Holl MM 《Langmuir : the ACS journal of surfaces and colloids》2004,20(26):11422-11427
Chemisorbed monolayers of octylgermane (C8H17GeH3) on gold have been formed by vapor deposition in ultrahigh vacuum. The monolayer has been characterized by X-ray photoelectron and reflection absorption infrared spectroscopies (XPS and RAIRS) and scanning tunneling microscopy (STM). XPS data indicate the monolayer can be oxidized by exposure to ozone. STM images exhibit a complex pattern which can be modeled as strain-mediated spinodal decomposition. 相似文献