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Geochemical CompGeochemical Comparison of Fresh and Weathered Tailings from the Sabodala Gold Mine Kedougou Region, Senegal Following 6 Years of Operationarison of Fresh and Weathered Tailings from the Sabodala Gold Mine Kedougou Region, Senegal Following 6 Years of Operation

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Journal of Geoscience and Environment Protection 2020年第7期8卷 177-194页

作者： Ibrahima Dia Mababa Diagne Mamadou Gueye Andrew Barnes Christian Mace Earth Sciences Institute Cheikh Anta Diop University Dakar Senegal Geochemic Ltd. Monmouthshire United Kingdom Teranga Gold Corporation Toronto Canada

The Sabodala gold mine is located in the Kedegou region in eastern Senegal near the border with Mali in a tropical Savannah climate zone with distinct wet and dry seasons. The mine has been operating since 2009 with active tailings deposition giving an ideal opportunity to study the weathering characteristics of carbonate rich tailings materials under real world conditions. The mine is operated in accordance with international best practice with regular monitoring of water quality and tailings chemistry in accordance with the international cyanide management code (ICMC) and also in order to monitor and control any potential impacts from Acid Rock Drainage and Metal Leaching (ARDML) that may be generated from the tailings materials and waste rock. In 2015 as part of a project looking at the potential for re-use of generated tailings as construction materials, a number of additional geochemical tests including whole rock assays, mineralogy, Acid Base Accounting in accordance with modified Sobek method with siderite correction, together with paste pH and electrical conductivity (Ec) measurements were undertaken. The purpose of the study was to update the predictions of the potential for ARDML generation and drainage pH in leachates forming from the Sabodala tailings. The tests were run on one composite weathered and 3 selective fresh samples collected by auger drilling on three holes over the tailing. Results have enabled a better understanding of the chemical weathering characteristics of finely ground tailings materials under tropical weathering conditions and the nature of secondary minerals precipitated.

关键词： Acid Base Accounting Neutralization Potential elemental analysis Mineralogy

Comparative Studies of Thermal Stability of Coal Tar Pitches

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Journal of Chemistry and Chemical Engineering 2012年第9期6卷 860-865页

作者： Andrey A. Gahguzov Valery V. Kulakov Denis I. Kalugin Artem P. Malakho Viktor V. Avdeev Chemistry Department Moscow State University Moscow 119991 Russia The Aircraft Corporation 《Rubin》 Balashikha 143900 Russia

In the present work, three medium softening point coal tar pitches were used for comparative thermal stability and under-storage stability investigation. Powders of the pitches were found to be different under storage： one of the pitches was caked and slumped after 7-day or longer storage. For thermal stability investigation the soft temperature treatment （265℃） of coal tar pitches was used. Detailed study of initial and treated pitches was carried out. Experimental results demonstrated that LMW-HC （high low-molecular-weight hydrocarbons） and oxygen content influence pitch quality characteristics in a negative way under long-term storage and lead to highest properties change after thermal stability treatment.

关键词： Coal tar pitch rheology thermal analysis toluene-insoluble quinoline-insoluble elemental analysis GCMS.

Research on the Distribution of Major Metal Elements in the Typical Landslide Soil of the Three Gorges Reservoir Area

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Research on the Distribution of Major Metal Elements in the ...

The Determination of Water Diffusion Coefficients and Dynamics in Adhesive/PI Film Bonded Joints

2011 World Congress on Engineering and Technology(CET 2011)

作者： Liu Luwen1 2 Xiang Wei2 Lin Zhaoxiang3 Liu Linmei3 Wu Jinquan3 1.School of Math and Physics China University of Geosciences Wuhan 430074 China 2.Faculty of Engineering China University of Geosciences Wuhan 430074 China 3.Lab.for Laser Spectrum Research South-Central University for Nationalities Wuhan 430074 China

In this paper,a laboratory-built experimental system---Laser-induced Breakdown Spectroscopy（LIBS）,is used to measure soil *** explores landslides band soil of five typical landslides in Xiangxi River section of the Three Gorges Reservoir Area,which include Bazimen landslide,Baijaibao landslide,Jiajiadian landslide,Sixiangxi landslide and an unnamed landslide that has already *** samples of the five landslides are taken in different latitudes,and in relatively consistent *** experimental measurement,the author gets spectrum of those soil samples,and then dose qualitative and quantitative analyses of elements（Mg,Si,K,Al, etc）in *** author concludes that main metal elements in the soil are changed according to different longitudes and latitudes,which opens up a new way of thinking for the quantitative analysis of the function of soil and water,and for the establishment of relations between chemical environment factors and soil engineering mechanics effects.

关键词： LIBS landslides band soil elemental analysis

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The Determination of Water Diffusion Coefficients and Dynami...

Characteristics of Self-Shielded Flux Cored Arc Welding Consumables for High Strength Steel Grades

第三届世界粘接及相关现象大会暨北京粘接学会第十五届学术年会

作者： C.WANG W.B.LIU Y.Q.LU J.H.LI College of Chemistry and Molecular Engineering Peking University Heilongjiang Petrochemistry Institute Harbin Engineering University Department of Public Courses Medical CollegeZhengzhou Railway Vocational and Technological College Department of Chemistry Daqing Vocational College

In this paper,water diffusion coefficients and dynamics in PI film/adhesive/PI film joints are determined with both energy dispersive X-ray spectroscopy and elemental *** energy dispersive X-ray spectroscopy analysis (EDX) is an easy and exact method for determination of water diffusion coefficients and *** we have calculated the water diffusion coefficients and dynamics in PI film/adhesive/PI film joints subjected to different surface treatments with both energy dispersive X-ray spectroscopy and elemental *** water diffusion coefficients and dynamics in the adhesive joints determined with EDX analysis are almost the same as those determined with elemental *** durability of the adhesive joints with PI film subjected to C06O irradiation is better than those subjected to acetone washing treatment and chemical treatment.

关键词： diffusion coefficients dynamics energy dispersive X-ray spectroscopy elemental analysis PI film/adhesive/PI film joints

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Characteristics of Self-Shielded Flux Cored Arc Welding Cons...

Synthesis and Molecular Structure of Bis-Ferrocene-Containing Acyl Thiourea Derivatives

第十届中国钢铁年会暨第六届宝钢学术年会

作者： Kuzmikova L. Han J. Zhu Z. Barbaro F.J. University of Wollongong

The most widely used processes for girth welding of pipelines constructed from API X80 is mechanised GMAW and SMAW in combination with cellulosic electrodes. However, both of these processes face certain limitations. Mechanised GMAW is not suitable for tie-ins, applications in difficult terrain and due to high mobilisation cost for use on short sections. Whereas SMAW with cellulosic electrodes presents significant challenges in terms of satisfying weld metal strength（over）matching requirements and high risk of HACC that is particularly critical for high strength large diameter thick wall pipelines. Low hydrogen basic electrodes have also been increasingly used especially those designed for vertical down application. However, the cost of these consumables is high and due to the unique operational characteristics require extensive welder training. Self-shielded FCAW（SS-FCAW） consumables offer a feasible alternative to these limitations. However, in recent years an increasing number of cases have been reported where the use of the SS-FCAW process produced welds with extremely poor toughness particularly when applied to high strength line pipe. This paper describes some initial results of weld metal dilution effects on Charpy impact toughness, which is part of an ongoing investigation into the performance of SS-FCAW consumables.

关键词： SS-FCAW weld consumable dilution elemental analysis API 5L X80 Charpy impact test

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有机化学 2003年第Z1期23卷 376-376页

作者： XU Yan FU Yong RAN Chun-Ling SONG Mao-Ping Department of Chemistry Zhengzhou University Zhengzhou 450052 Department of Chemistry Zhengzhou University Zhengzhou 450052 Department of Chemistry Zhengzhou University Zhengzhou 450052 Department of Chemistry Zhengzhou University Zhengzhou 450052

　　Ferrocene is a compound with excellent stability. In addition, it has very favourable electrochemical properties. So the synthesis, structure, electrochemistry and coordination behaviors of ferrocene-derivatives have attracted considerable attention in recent years.[1,2] Electrondonating atoms such as N, S, O in the derivatives are known for their coordination particularly with transition metals. [3] Two new bis-ferrocene-containing acyl thiourea derivatives are synthesized. The derivatives are confirmed by IR spectrum, 1H NMR and elemental analysis. These compoundshave many electrondonating atoms and two ferrocenes. The structure of one compound is shown below. The study onelectrochemistry and coordination behaviors is in the progress.……

关键词： Thiourea Derivatives electrochemical properties thiourea derivatives elemental analysis transition metals IR spectrum

Synthesis of Covalently-Linked Linear Donor-Acceptor Copolymers Containing Porphyrins and Oligothiophenes

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有机化学 2004年第Z1期24卷 290-页

作者： DUANMU,Chuan-Song CHEN,Zhang-Ping YU,Xue-Song College of Chemistry and Molecular Sciences Wuhan Universit Wuhan 430072 College of Chemistry and Molecular Sciences Wuhan Universit Wuhan 430072 College of Chemistry and Molecular Sciences Wuhan Universit Wuhan 430072

　　5,15-Di-bithienyl porphyrin (1) and its Cu(Ⅱ), Zn (Ⅱ) complexes (2 and 3)[1] were polymerized according to Scheme 1 by chemical oxidation using FeCl3 as oxidant for making organic conductor, and the linear porphyrin-thiophene copolymers were obtained. The structures of the copolymers were identified by elemental analysis and IR spectra. The conductivity of poly 5,15-di-bithienyl porphyrin (4) doped with FeCl3 was measured to reach over 10-6 S/cm, which was in the range of semiconductor and higher than that of other porphyrin-thiophene copolymers prepared by Shimidzu. The higher conductivity may be due to the better conjugation between the thienyl group and the porphyrin ring. The thienylporphyrins 7 and 8 could not be polymerized under the similar conditions, but could be polymerized by electrochemical oxidation (working electrode: gold-plate electrode; counter electrode: platinum; reference: standard calomel electrode SEC; solvent: 0.1 mol·dm-3 n-Bu4NClO4 in dry MeCN).……

关键词： electrochemical oxidation elemental analysis organic conductor IR spectra range of

Solvent-free Synthesis of 5-Azacytosine with Microwave Activation

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有机化学 2003年第Z1期23卷 106-106页

作者： QU Gui-Rong LIU Qi-Bin ZHANG Wen-Sheng Feng Feng Key Laboratory of Environmental Science and Technology of High Education of Henan Province College of Chemical & Environmental Science Henan Normal University Xinxiang 4530022 Department of Chemistry Jiaozuo Normal College Jiaozuo 454151

5-Azacytosine (4-amino-1,2-dihydro-1,3,5-triazin-2-one) is a very important intermediate in the synthesis of 5-azacytidine which shows remarkable bacteriostatic and cytostatic activity as well as against T-4 lymphoma and L1210 leukemia in mice. Starting with N-cyanoguanidine (dicyandiamide) and formic acid, under the solvent-free microwave activation, we synthesized 5-azacytosine in short time (4 min) with good yield (60.4%). The structure of the product was confirmed by 1H NMR and elemental analysis.……

关键词： microwave activation elemental analysis formic acid

Studies on the Fluorescence Properties of Chloromethyl Polystyrene Supported Fluorophore

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Chemical Research in Chinese Universities 2001年第Z1期17卷 213-页

作者： REN HongXia Department of Chemistry Shanxi University Department of Chemistry Northwest Normal University Lanzhou

The basic materials used in making photoluminescence materials are all synthesized polymers at present, such as PVC, etc [1]. Red and green LEDs are easy to be prepared, but the blue LED is difficult to be done. In this paper, we used chloromethyl polystyrene as supporter, leading into the known fluorophore by polymer chemical reaction, so as to obtaining blue luminous material.The PS-CH2Cl supported fluorophore are prepared by PS-CH2Cl and benzidine (B), dimethylbenzidine (MA), 4,4'-diamino-diphenyl ether (DAPE), 4,4'-diamino-diphenyl sulfone (DAPS), respectively. They were characterized by IR and elemental analysis. The stead state fluorescence properties of these supported polymers were *** results were summarized in table 1.

关键词： fluorescence properties elemental analysis luminous material chemical reaction basic materials used in