复配农药制剂丙溴磷·毒死蜱的气相色谱同时分析方法研究

建立气相色谱法同时测定丙溴磷和毒死蜱含量的分析方法,OV-101为固定液的石英毛细管柱,邻苯二甲酸二异丙酯为内标物。实验表明,丙溴磷和毒死蜱的线性相关系数分别为0.998 8和0.996 7,平均回收率分别为99.64%和99.71%。     

复配农药制剂丙溴磷·毒死蜱的气相色谱同时分析方法研究

建立气相色谱法同时测定丙溴磷和毒死蜱含量的分析方法,OV-101为固定液的石英毛细管柱,邻苯二甲酸二异丙酯为内标物。实验表明,丙溴磷和毒死蜱的线性相关系数分别为0.9988和0.9967,平均回收率分别为99.64％和99.71％。     

A method for the simultaneous analysis of unconjugated and glycine-conjugated bile acids by capillary gas-liquid chromatography

A method for the simultaneous analysis of unconjugated and glycine-conjugated bile acids by means of capillary gas-liquid chromatography without need for prior deconjugation is described. The method involves: i) the use of an aluminum-clad fused-silica capillary column coated with a very thin film (0.1 μm) of a highly thermostable bonded and crosslinked methyl polysiloxane, and ii) the analysis of the bile acids as their methyl ester-dimethylethylsilyl ether derivatives. This method, used to separate the major free and glycine-conjugated bile acids from human gall bladder bile, should be applicable for the analysis of other biological fluids.     

Dry column method for the quantitative extraction and simultaneous class separation of lipids from muscle tissue

A method for lipid isolation is presented that is alternative to the traditional chloroform/methanol extraction methods. This new method allows lipid isolation by solvent elution of a dry column composed of a tissue sample, anhydrous sodium sulfate, and Celite 545 diatomaceous earth groud together. To isolate total lipids, the dry column is eluted with a mixture of dichloromethane/methanol (90∶10, v/v). Alternatively, the lipids may be isolated and simultaneously separated into neutral and polar fractions by a sequential elution procedure; neutral lipids free of polar lipids are eluted first with dichloromethane, followed by elution of polar lipids with the dichloromethane/methanol (90∶10) mixture. The two dry column methods-isocratic or sequential elution-were compared with the traditional chloroform/methanol methods by gravimetric, thin layer chromatographic and phosphorus analyses. Presented in part at the AOCS 70th Annual Meeting, San Francisco, May 1979. Agricultural Research, Science and Education Administration, U.S. Department of Agriculture.     

A simple HPLC method for the simultaneous analysis of phosphatidylcholine and its partial hydrolysis products 1- and 2-acyl lysophosphatidylcholine

A simple HPLC method for the simultaneous analysis of phosphatidylcholine (PC), 1-acyl lysophosphatidylcholine (1-acyl LPC), and 2-acyl lysophosphatidylcholine (2-acyl LPC) with refractive index detection is described. The separation of these three compounds was achieved on a Waters (Milford, MA) Spherisorb amino phase column using a mixture of ethanol and an aqueous oxalic acid solution as eluent. The optimal mixture of ethanol to oxalic acid solution was 92∶8 (vol/vol). PC and the two regioisomers of LPC eluted within 15 min. The calibration curves were linear in a concentration range from 0.05 to 2.5 mM. Natural PC or LPC eluted in a single peak, despite the diversity in the fatty acid composition. There was no rearrangement between 1-acyl LPC and 2-acyl LPC during analysis or storage in ethanol within 23 h. This method is thus especially suitable for studying reactions on PC and acyl migration in LPC.     

A practical equation of state for non‐spherical and asymmetric systems for application at high pressures. Part 1: Development of the pure component model

A practical, mathematically and computationally simple, equation of state (EOS) has been developed to accurately describe pure component phase behaviour of spherical and chain‐like molecules. The EOS consists of a newly developed hard sphere model and a perturbation term based on the Barker and Henderson approach using the Chen and Kreglewski intermolecular potential model and a double constrained summation as a mathematical expression thereof. The perturbed hard chain theory (PHCT) approach is used to extend the EOS to non‐spherical molecules. The EOS compares well with other more complex models such as the simplified perturbed hard chain theory (SPHCT) and statistically associating fluid theory (SAFT) models and will be extended to describe mixtures in Part 2 of this series. © 2011 Canadian Society for Chemical Engineering     

氯乙烯精馏尾气回收膜分离法与变压吸附法的对比分析

介绍了电石法PVC树脂生产过程中氯乙烯精馏尾气的吸收方法,从原理到回收情况对比了膜吸附回收法和变压吸附法。结果表明,采用变压吸附法回收氯乙烯精馏尾气不仅降低了消耗,增加了经济效益,而且减少了环境污染。     

New data analysis method for the evaluation of ionization constants and other thermodynamic functions from the temperature dependence of the electromo tive force of cells

A multilinear regression method is presented by which the analysis of emf data for electrochemical cells as a function of electrolyte concentration and temperature is achieved in a single stage yielding thermodynamic quantities and their estimated standard errors. This procedure is considered to be an advance over the two-stage method of treating the concentration and temperature variation separately. The new method is applied to selected literature data for the evaluation of the standard potential of the silver—silver chloride electrode, the autoprotolysis constants of light and heavy waters and the second ionization constant of glycerol-2-phosphate.