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排序方式: 共有137条查询结果,搜索用时 296 毫秒
61.
B. E. Burpitt L. P. Crawford B. J. Davies J. Mistry M. B. Mitchell K. D. Pancholi W. J. Coates 《Journal of heterocyclic chemistry》1988,25(6):1689-1695
Two synthetic routes to the dihydropyridazinone-cyanoguanidine 4 (SK&F 94836) are described, both proceeding via the anilino compound 6. An efficient synthesis of the dihydropyridazinone-pyridone 5 (SK&F 95654) is reported. This synthesis proceeds via the fluoro-keto-acid 24 , with subsequent displacement of the fluoro substituent by 4-pyridone. The surprising effectiveness of water as a solvent in this reaction has been highlighted. 相似文献
62.
A mixture of manganese dioxide and hydrochloric acid has been used for the accurate and precise determination of gold in
various gold-bearing matrices. Results of intermethod comparison studies, F-test on variances, Mann-Whitney U-test, Spearman
rank correlation and regression analyses are presented. The recommended method can be applied to a quality control programme
and for the evaluation of reference materials. Various standard reference materials (SRM) of diverse matrices have been examined
to check the validity of the method and the results were found to be in very good agreement with the certified data. Sample
decomposition is straight forward [1–10 g sample (roasted at 600–700 °C)+5 g of MnO2+30 mL of 2 mol/L HCl]. Gold is coprecipitated with potassium tellurite using tin (II) chloride solution. The precipitate
is extracted into toluene and finally stripped back into aqua-regia solution for final nebulization into an air-acetylene
flame for atomic absorption spectrophotometry. The method is very simple and easily adaptable, and more convenient than conventional
methods involving aqua regia or a hydrobromic acid-bromine water mixture.
Received: 23 October 1995/Revised: 18 March 1996/Accepted: 23 March 1996 相似文献
63.
Ultrasonic irradiation has been found to accelerate the solvolysis of 2-chloro-2-methylpropane in aqueous ethanol mixtures from 20 to 60% w/w in ethanol at temperatures between 10° and 25°. The effects are more marked at lower temperatures and higher alcohol compositions with a 20 fold rate acceleration occurring at 10° and 60% w/w. The results also lend independent support to two previous observations that (a) the position of maximum in solvent structuredness is 50% w/w and (b) a logarithmic relationship exists between solvent vapour pressure and ultrasonically enhanced rate constant. At solvent compositions of 50 and 60% w/w ethanol the absolute rate of reaction under irradiation increases with decreasing reaction temperature below 20°. 相似文献
64.
Brock IC Ferguson T Vogel H Bebek C Berkelman K Blucher E Byrd J Cassel DG Cheu E Coffman DM Copie T Crawford G DeSalvo R DeWire JW Ehrlich R Galik RS Gittelman B Gray SW Halling AM Hartill DL Heltsley BK Kandaswamy J Kowalewski R Kreinick DL Kubota Y Lewis JD Mistry NB Mueller J Namjoshi R Nandi S Nordberg E Perticone D Peterson D Pisharody M Riley D Silverman A Stone S Worris M Sadoff AJ Avery P Besson D Garren L Yelton J Bowcock T Kinoshita K Pipkin FM Procario M Wilson R Wolinski J Xiao D 《Physical review D: Particles and fields》1991,43(5):1448-1458
65.
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
66.
Bortoletto D Brown DN Dominick J McIlwain RL Miller DH Modesitt M Shibata EI Schaffner S Shipsey IP Battle M Kroha H Sparks K Thorndike EH Wang C Goldberg M Haupt T Horwitz N Jain V Moneti GC Rozen Y Rubin P Skwarnicki T Sharma V Stone S Thusalidas M Yao W Zhu G Barnes AV Bartelt J Csorna SE Letson T Mestayer MD Alexander J Artuso M Bebek C Berkelman K Besson D Browder TE Cassel DG Cheu E Coffman DM Drell PS Ehrlich R Galik RS Garcia-Sciveres M Geiser B Gittelman B Gray SW Halling AM Hartill DL 《Physical review D: Particles and fields》1992,45(1):21-35
67.
Premaditya Chhetri Dieter Ackermann Hartmut Backe Michael Block Bradley Cheal Christoph Emanuel Düllmann Julia Even Rafael Ferrer Francesca Giacoppo Stefan Götz Fritz Peter Heßberger Oliver Kaleja Jadambaa Khuyagbaatar Peter Kunz Mustapha Laatiaoui Felix Lautenschläger Werner Lauth Enrique Minaya Ramirez Andrew Kishor Mistry Sebastian Raeder Calvin Wraith Thomas Walther Alexander Yakushev 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2017,71(7):195
68.
A. K. Mistry R. -D. Herzberg P. T. Greenlees P. Papadakis K. Auranen P. A. Butler D. M. Cox A. B. Garnsworthy T. Grahn K. Hauschild U. Jakobsson D. T. Joss R. Julin S. Ketelhut J. Konki M. Leino A. Lopez-Martens R. D. Page J. Pakarinen P. Peura P. Rahkila M. Sandzelius C. Scholey J. Simpson D. Seddon J. Sorri S. Stolze J. Thornhill J. Uusitalo D. Wells 《The European Physical Journal A - Hadrons and Nuclei》2017,53(2):24
69.
L. Herrag M. Bouklah N. S. Patel B. M. Mistry B. Hammouti S. Elkadiri M. Bouachrine 《Research on Chemical Intermediates》2012,38(7):1669-1690
The inhibition of the corrosion of mild steel 1 M HCl solution by some diamine compounds has been investigated in relation to the concentration of the inhibitor as well as the temperature using weight loss and electrochemical measurements. The effect of the temperature on the corrosion behavior with the addition of different concentrations of new diamine compounds (3-[2-(2-cyano-ethylamino)-methylamino]-propionitrile (P1); 3-[2-(2-cyano-ethylamino)-ethylamino]-propionitrile (P2), and 3-[6-(2-cyano-ethylamino)-hexylamino]-propionitrile (P3), respectively, was studied in the temperature range 40–80 °C. Polarization curves reveal that (P1, P2, and P3) are mixed type inhibitors. The inhibition efficiency of organic compounds is temperature independent, but increases with the inhibitor concentration. Adsorption of inhibitor on the carbon steel surface is found to obey the Langmuir adsorption isotherm. Some thermodynamic functions of dissolution and adsorption processes were also determined. On the other hand, and in order to determine the relationship between the molecular structure of these compounds and inhibition efficiency, quantum chemical parameters were calculated. The theoretically obtained results were found to be consistent with the experimental data. 相似文献
70.
Edwards MH Whittaker D Mistry P Booth N Pert GJ Tallents GJ Rus B Mocek T Koslová M McKenna C Delserieys A Lewis CL Notley M Neely D 《Physical review letters》2006,97(3):035001
The temporal evolution of the opacity of an iron plasma at high temperature (30-350 eV) and high density (0.001-0.2 g cm-3) has been measured using a nickel-like silver x-ray laser at 13.9 nm. The hot dense iron plasma was created in a thin (50 nm) iron layer buried 80 nm below the surface in a plastic target that was heated using a separate 80 ps pulse of 6-9 J, focused to a 100 microm diameter spot. The experimental opacities are compared with opacities evaluated from plasma conditions predicted using a fluid and atomic physics code. 相似文献