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Sonochemical degradation of organophosphorus pesticide in dilute aqueous solutions

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Journal of Environmental Sciences 2003年第5期15卷 710-714页

作者： RobinaFarooq LINFeng-kai S.F.Shaukat: HUANGJian-jun collegeofresourcesandenvironmentalengineering EastChinaUniversityofS&TShanghai200237China DepartmentofPhysics GovernmentCollegeLahore.Pakistan

Ultrasonic irradiation was found to accelerate the rate of hydrolysis of omethoate in aqueous solution over the pH range of 2—12 Process parameters studied include pH, steady state temperature, concentration, and the type of gases. Greater than 96% hydrolysis was observed in 30 minutes through this process and the rate of destruction increased with the help of more soluble and low thermal inert gas. So with Krypton, omethoate was found to undergo rapid destruction as compared with Argon. In the presence of ultrasound, the observed first order rate of hydrolysis of omethoate is found to be independent of pH. The formation of transient supercritical water(SCW) appears to be an important factor in the acceleration of chemical reactions in the presence of ultrasound. A detailed chemical reaction mechanism for omethoate destruction in water was formulated. Experimental results and theoretical kinetic mechanism demonstrated that the most of the omethoate undergo destruction inside the cavitating holes. A very less effect of temperature on the degradation of omethoate within a temperature range of 20—70℃ proves that a small quantity of omethoate undergoes secondary destruction in the bulk liquid.

关键词： sonochemical degradation omethoate pesticide sonolysis role of inert gases

Sonochemical Behavior of Aqueous Solutions of Iodide, Bromide and Azide

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Journal of Shanghai University(English Edition) 2002年第3期6卷 255-259页

作者：林逢凯黄建军 collegeofresourcesandenvironmentalengineering EastChinaUniversityofScienceandTechnologyShanghai200237China

The sonolysis of azide solutions was investigated. The main product isnitrogen, which is formed in the reaction of N_3^- with OH radicals in the millimolar concentrationrange. At higher azide concentration, additional nitrogen is formed as hydrogen atoms are *** and hydrazine are minor products of the N_3^- sonolysis. Solutions of iodide and bromideare also irradiated under pH conditions where reactions of the products, i.e., hydrogen per oxideand iodide (or bromide) do not occur. The total yield of the products as well as the hydrogen yieldis independent of the solute concentration. The results are understood in terms of the competitionof the OH + OH and the OH + solute reactions. A local concentration of 4 X 10^(-3) mol/L of the OHradicals in an interfacial region between the cavitation bubbles and the liquid is derived from thedata obtained.

关键词： sonolysis iodide bromide azide ultrasound.

Quality index of bedded and joint-bearing rock mass and its applications

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Journal of Coal Science & Engineering(China) 2002年第2期8卷 12-16页

作者：姜福兴秦忠诚蒋国安 collegeofresourcesandenvironmentalengineering ShandongUniversltyofSclenceandTechnologyTal‘an271019China collegeofresourcesandenvironmentalengineering ShandongUniversltyofSclenceandTechnologyTal’a

Based on the theory of Fuzzy Mathematics and Expert System, this paper presents the quantitative expression method of bedded and joint bearing rock mass quality "Stratum Quality Index"(SQI for short), and also introdu... 详细信息

关键词：地层模糊数学专家系统岩体质量指标岩层移动

Formation mechanism of ferromagnetic minerals in loess of China:TEM investigation

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Chinese Science Bulletin 2003年第20期48卷 2259-2266页

作者： CHENTianhu XUHuifang JIJunfeng CHENJun CHENYang collegeofresourcesandenvironmentalengineering HefeiUniver-sityofTechnololzyHefei230009China DepartmentofEarthandPlanetarySciences TheUniversityofNewMexicoNM87131USA InstituteofSurficialGeochemistry DepartmentofEarthSciencesNanjingUniversityNanjing210093China

The results of TEM investigation indicate that magnetite and maghemite are the major ferromagnetic minerals in loess-paleosol sequences. Primary magnetite has the similar morphology and surface characteristics as eolian detrital particles. The magnetite can be classified into two categories, high-titanium and low-titanium, which may be the indicators of magmatic rocks and metamorphic rocks, respectively. TEM investigation at nanometer scale shows that primary detrital magnetite of micron scale had been partially weathered to maghemite of 5～20 nanometer during the pedogenic process, which maintain the pseudomorphism of the aeolian debris. Some chlorite particles were also weathered to nanometer scale magnetite or maghemite in the pedogenic process. So weathering of the two minerals leads to formation of superparamagnetism, which may be the important mechanism of magnetic-susceptibility increase in paleosols. The magnetite or maghemite resulting from the weathering of chlorite contains a small amount of P and S, which is the signal of microbe-mineral interaction, and indicates that microbes may play a certain role in chlorite weathering and formation of superparamagnetic particles.

关键词：铁磁性矿物中国黄土-古土壤序列透射电子显微镜磁铁矿磁赤铁矿

S tudy on Doped Fluoride Glasses for Scintillation Applications

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Journal of Shanghai University(English Edition) 2002年第4期6卷 303-306页

作者： Shaukat S F. Farooq R 等 DepartmentofCehmistry EastChinaUniversityofScienceandTechnologyShanghai200237China collegeofresourcesandenvironmentalengineering EastChinaUniversityofScienceandTechnologyShangh

This paper studies the properties of fluoride glasses for use in particle calorimeters or in optical fibers. The effects of major and minor impurities in manufacturing process and ultimately on the glass properties have been investigated. Glasses in a range of compositions have been made and tested in the form of small samples as well as larger blocks of size 2×3×14 cm 3. Results of measurements on these materials, using a high energy particle beam, are presented.

关键词： heavy metal fluoride glasses scintillation electromagnetic calorimeter.