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101.
102.
The first stability constants (log beta(1)) of the copper(II) complex of glycine in water and in 13 water + alcohol (isopropanol, tert-butanol, 1,2-propylene glycol and glycerol) solvents have been determined at 25 degrees C and an ionic strength of 0.10, from pH and pCu measurements of cells containing copper(II) ion selective electrode. It has been shown that as the proportion of the alcohol increases, the stability constants become increasing positive in all of the mixed solvents examined. An almost linear relation between log beta(1) and the mole fraction of alcohol was found for the complex in aqueous solutions of isopropanol, tert-butanol and glycerol. The response of the copper(II) ion selective electrode in water and in water + alcohol mixed solvents was also investigated. The advantages of using an ion selective electrode to determine the stability constants in mixed solvents are discussed. 相似文献
103.
The double-T injector design employed in many microchip capillary electrophoresis devices allows for the formation of very small (50-500 pL) sample plugs for subsequent analysis on-chip. In this study, we show that sample plugs formed at the channel junction can be geometrically defined. The channel width and injector symmetry prove to be of great importance to good performance. A unique pushback of solvent into the side channels can be induced when the side channels have a very low resistance to flow, and this helps to better define the injected sample plug. Samples and running buffers of differing ionic strength (e.g., 10 mM KCl buffer and 20 mM KCl sample) can yield widely variable results in terms of plug shape and amount injected (variations of 1.5 to 10x). Applying bias voltages to all the intersecting channels aids in controlling the plug shape. However, when the ionic strengths of buffer and sample are not matched, the actual amount injected (up to 10x variations) can be inconsistent with the appearance of the plug formed in the injector (up to only 30 % variations). Operating at constant pH and ionic strength produced the most consistent results. This report examines the effects of altering the injector geometry and solution ionic strengths, and presents the results of using bias voltages to control plug formation. The observed results should provide a benchmark for modeling of the fluid dynamics in channel intersections. 相似文献
104.
105.
X. Y. Zhang S. Jin Y. C. Liang Y. F. Ming L. H. Yu M. G. Fan W. F. Wang S. D. Yao 《Research on Chemical Intermediates》1995,21(1):17-24
Photochromic reactions of four indolinospirooxazine derivatives have been studied using nanosecond laser flash photolysis
techniques. Photolysis of the four compounds in acetonitrile and in cyclohexane all leads to the formation of the short-lived
CT intermediates as the predominant photoproducts. In certain circumstances few photomerocyanines (PMC) can be observed. From
the absorption bands and the lifetimes of CT intermediates, it has been speculated that the substituents at the nitrogen atom
of the indole ring influence the structural characteristics of CT intermediates mainly through steric hindrance effects, whereas
the substituents at the 5 position of the indoline ring influence mainly through electron effects. A potential energy surface
model is established to explain the results. 相似文献
106.
Science China Mathematics - Let w be a permutation of {1, 2, …, n}, and let D(w) be the Rothe diagram of w. The Schubert polynomial ${\mathfrak{S}_w}\left(x \right)$ can be realized as the... 相似文献
107.
Abe K Abt I Ahn CJ Akagi T Ash WW Aston D Bacchetta N Baird KG Baltay C Band HR Barakat MB Baranko G Bardon O Barklow T Bazarko AO Ben-David R Benvenuti AC 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 Cassell R Castaldi R Castro A Cavalli-Sforza M Church E Cohn HO Coller JA Cook V Cotton R Cowan RF Coyne DG D'Oliveira A Damerell CJ Dasu S 《Physical review letters》1995,74(9):1512-1516
108.
109.
Abe K Abt I Ahn CJ Akagi T Allen NJ Ash WW Aston D Baird KG Baltay C Band HR Barakat MB Baranko G Bardon O Barklow T Bazarko AO Ben-David R Benvenuti AC 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 Cassell R Castaldi R Castro A Cavalli-Sforza M Church E Cohn HO Coller JA Cook V Cotton R Cowan RF Coyne DG D'Oliveira A Damerell CJ Daoudi M 《Physical review D: Particles and fields》1995,52(7):4240-4244
110.
Bai JZ Bardon O Blum I Breakstone A Burnett T Chen GP Chen HF Chen J Chen SJ Chen SM Chen Y Chen YB Chen YQ Cheng BS Cowan RF Cui HC Cui XZ Ding HL Du ZZ Dunwoodie W Fan XL Fang J Fero M Gao CS Gao ML Gao SQ Gao WX Gratton P Gu JH Gu SD Gu WX Gu YF Guo YN Han SW Han Y Harris FA Hatanaka M He J He KR He M Hitlin DG Hu GY Hu HB Hu T Hu XQ Huang DQ Huang YZ Izen JM Jia QP Jiang CH Jin Y Jones L Kang SH Kelsey MH Kim BK Lai YF Lan HB Lang PF Lankford A Li F Li J Li PQ Li Q Li RB 《Physical review D: Particles and fields》1995,52(7):3781-3784