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用组分分离法书写混合溶液的质子守恒式 被引量:9
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作者 曾应超 《化学教学》 CAS 北大核心 2013年第5期70-71,共2页
通过对书写混合溶液质子守恒式时存在的困难进行分析,介绍了一种易于掌握的快捷书写方法一一组分分离法。结合具体实例,对利用组分分离法书写质子守恒式的基本步骤进行了阐述,并指出了应用组分分离法书写混合溶液质子守恒式的关键点。
关键词 组分分离法 混合溶液 质子守恒式
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煤的化学族组成研究(Ⅱ)煤的可溶化体系的优化 被引量:5
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作者 田原宇 申曙光 谢克昌 《煤炭转化》 CAS CSCD 北大核心 2002年第1期28-32,共5页
煤的可溶化体系是煤化学族组成研究的前提和关键,通过从高抽提率、溶剂回收性、普遍适应性、快捷省时、方便准确等方面综合考察溶剂选择、溶剂组合方式、溶剂抽提方式等因素对煤可溶化的影响,提出了一套较为优化的可溶化体系,以满足... 煤的可溶化体系是煤化学族组成研究的前提和关键,通过从高抽提率、溶剂回收性、普遍适应性、快捷省时、方便准确等方面综合考察溶剂选择、溶剂组合方式、溶剂抽提方式等因素对煤可溶化的影响,提出了一套较为优化的可溶化体系,以满足煤化学族组成研究的需要. 展开更多
关键词 化学族 组成 可溶化体系 体系优化 组分分离法
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基于化学族组成的煤化学研究体系构建及其应用 被引量:5
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作者 田原宇 谢克昌 +1 位作者 乔英云 田斌 《煤炭学报》 EI CAS CSCD 北大核心 2021年第4期1137-1145,共9页
针对170多年来按照物理相似性、以显微组分为基础的传统煤化学研究方法普适性差和近70 a来借助现代分析仪器和量子化学计算得到的煤大分子结构模型无法解析煤结构和反应性的关联性的核心科学问题,提出表征可溶化程度的相对抽提率概念,... 针对170多年来按照物理相似性、以显微组分为基础的传统煤化学研究方法普适性差和近70 a来借助现代分析仪器和量子化学计算得到的煤大分子结构模型无法解析煤结构和反应性的关联性的核心科学问题,提出表征可溶化程度的相对抽提率概念,构建了基于环己酮和CS_(2)-NMP复合溶剂分步抽提煤的普适性可溶化体系,按照化学相似性将煤中有机物分为饱和分、芳香分,胶质、沥青质、碳青质和焦质6个化学族组分,开展不同变质程度煤化学族组分的物理化学结构、组成及其不同热解条件下的热解行为、热解特性、反应机理与动力学研究;提出煤热解反应主体由热离解的自由基主导的新观点,构建了普适性的煤热解自由基调控机理及其强化机制,并按照煤化学族组分的基元反应产生初始自由基、自由基调控和自由基复合3个阶段的反应机理合理有效地解析了煤等离子热解制乙炔过程反应历程与机理以及产物中乙炔选择性高达80%以上的现象、低阶煤快速热解提质实现焦油收率最大化的适宜条件等工业现象,从而形成了基于化学族组成的现代煤化学研究方法,实现了从分子水平识别、表征和描述煤的组成和物理与化学结构参数、煤中各种化学键和有害组分的存在形态,进而利用煤的化学族组成从分子水平研究煤转化过程的反应历程、反应机理和反应动力学,揭示各种煤在反应性方面的相似之处,提高煤转化过程效率、降低污染排放,为煤炭资源的高效清洁转化与利用提供借鉴。 展开更多
关键词 煤可溶化 化学族组分 6组分分离法 自由基调控机理 分子水平结构 反应性
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污水处理厂脱水污泥中重金属的分布规律 被引量:1
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作者 徐骏 朱伟 《水资源保护》 CAS 2014年第2期62-66,共5页
针对污泥中重金属赋存形态尚不明确的问题,使用MacNicol提出的组分分离方法,以3个污水处理厂污泥为对象,研究了重金属在无机颗粒、生物絮团、胶粒、流动相4个组分中的分配情况。结果表明,脱水污泥的干物质中颗粒组分和生物絮团组分... 针对污泥中重金属赋存形态尚不明确的问题,使用MacNicol提出的组分分离方法,以3个污水处理厂污泥为对象,研究了重金属在无机颗粒、生物絮团、胶粒、流动相4个组分中的分配情况。结果表明,脱水污泥的干物质中颗粒组分和生物絮团组分约占到了67%~94%,而在脱水污泥中颗粒组分和生物絮团仅占7%~22%,大多数属于流动相。这一组成特性决定了脱水污泥的大部分重金属分布在污泥流动相中,无机颗粒、生物絮团、胶粒中的重金属只占很少一部分。但从赋存浓度来看,流动相重金属浓度很低,相反有机相胶粒组分中重金属浓度较高。 展开更多
关键词 脱水污泥 组分分离法 重金属分布 污水处理厂
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A review of state-of-the-art processing operations in coal preparation 被引量:7
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作者 Noble Aaron Luttrell Gerald H. 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2015年第4期511-521,共11页
Coal preparation is an integral part of the coal commodity supply chain. This stage of post-mining, pre-utilization beneficiation uses low-cost separation technologies to remove unwanted mineral matter and moisture wh... Coal preparation is an integral part of the coal commodity supply chain. This stage of post-mining, pre-utilization beneficiation uses low-cost separation technologies to remove unwanted mineral matter and moisture which hinder the value of the coal product. Coal preparation plants typically employ several parallel circuits of cleaning and dewatering operations, with each circuit designed to optimally treat a specific size range of coal. Recent innovations in coal preparation have increased the efficiency and capac- ity of individual unit operations while reinforcing the standard parallel cleaning approach. This article, which describes the historical influences and state-of-the-art design for the various coal preparation unit operations, is organized to distinguish between coarse/intermediate coal cleaning and fine/ultrafine coal cleaning. Size reduction, screening, classification, cleaning, dewatering, waste disposal unit operations are particularly highlighted, with a special focus on the LI.S. design philosophy. Notable differences between the U.S. and international operations are described as appropriate. 展开更多
关键词 Coal preparation Coal supply chain Unit operations Particulate separations Tailings disposal
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RESEARCH OF QUANTUM GENETIC ALGORITH AND ITS APPLICATION IN BLIND SOURCE SEPARATION 被引量:60
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作者 Yang Junan Li Bin Zhuang Zhenquan (Department of Electronic Science & Technology, USTC, Hefei 230026) 《Journal of Electronics(China)》 2003年第1期62-68,共7页
This letter proposes two algorithms: a novel Quantum Genetic Algorithm (QGA)based on the improvement of Han's Genetic Quantum Algorithm (GQA) and a new Blind Source Separation (BSS) method based on QGA and Indepen... This letter proposes two algorithms: a novel Quantum Genetic Algorithm (QGA)based on the improvement of Han's Genetic Quantum Algorithm (GQA) and a new Blind Source Separation (BSS) method based on QGA and Independent Component Analysis (ICA). The simulation result shows that the efficiency of the new BSS method is obviously higher than that of the Conventional Genetic Algorithm (CGA). 展开更多
关键词 Quantum computation Genetic algorithm Quantum genetic algorithm Independent component analysis Blind source separation
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Isolation and characterization of wood components with aqueous acetic acid
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作者 LI Gai-yun QIN Te-fu 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第1期62-64,共3页
A study was conducted on the isolation of poplar (Populusxeurarnaricana (Dode) Guineir cv. I -72/58) wood components with aqueous acetic acid (AcOH) containing small amounts of sulfuric acid. The reaction time, ... A study was conducted on the isolation of poplar (Populusxeurarnaricana (Dode) Guineir cv. I -72/58) wood components with aqueous acetic acid (AcOH) containing small amounts of sulfuric acid. The reaction time, concentration of acetic acid, ratio of liquor to wood, and concentration of acid catalyst were investigated to examine their effects on the fractionation of wood components. The three main separated components were characterized. The results showed that the optimum conditions for fractionation of poplar wood components were: 0.3% H2SO4 in reaction solution, ratio of liquor to wood 6, reflux time 3 h, and 90% AcOH. The residues were mainly composed of a-Cellulose and hemicellulose, The water insoluble precipitate (acetic acid lignin, AcL) had a low weight-average molecular weight range from 341 to 253 (Mw) and a narrow molecular weight distribution from 1.1 to 1.2. The sugar analysis revealed the solubilized products resulted mainly from hemicellulose and exited as monosaccharides. 展开更多
关键词 Aqueous acetic acid Sulfuric acid Component separation Poplar wood
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Methods Comparison for Microsatellite Marker Development:Different Isolation Methods,Different Yield Efficiency 被引量:1
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作者 ZHAN Aibin BAO Zhenmin HU Xiaoli LU Wei HU Jingjie 《Journal of Ocean University of China》 SCIE CAS 2009年第2期161-165,共5页
Microsatellite markers have become one kind of the most important molecular tools used in various researches. A large number of microsatellite markers are required for the whole genome survey in the fields of molecula... Microsatellite markers have become one kind of the most important molecular tools used in various researches. A large number of microsatellite markers are required for the whole genome survey in the fields of molecular ecology,quantitative genetics and genomics. Therefore,it is extremely necessary to select several versatile,low-cost,efficient and time-and labor-saving methods to develop a large panel of microsatellite markers. In this study,we used Zhikong scallop(Chlamys farreri) as the target species to compare the efficiency of the five methods derived from three strategies for microsatellite marker development. The results showed that the strategy of constructing small insert genomic DNA library resulted in poor efficiency,while the microsatellite-enriched strategy highly improved the isolation efficiency. Although the mining public database strategy is time-and cost-saving,it is difficult to obtain a large number of microsatellite markers,mainly due to the limited sequence data of non-model species deposited in public databases. Based on the results in this study,we recommend two methods,microsatellite-enriched library construction method and FIASCO-colony hybridization method,for large-scale microsatellite marker development. Both methods were derived from the microsatellite-enriched strategy. The experimental results obtained from Zhikong scallop also provide the reference for microsatellite marker development in other species with large genomes. 展开更多
关键词 MICROSATELLITE marker development isolation efficiency method comparison SCALLOP
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褐煤的化学族组成研究方法及应用 被引量:2
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作者 田原宇 乔英云 刘芳 《腐植酸》 2006年第4期31-34,共4页
利用化学族组成研究方法对褐煤进行分子水平研究。介绍褐煤化学族组成研究的思路,六组分的定义和划分,并建立了褐煤的六组分分离法,为褐煤生产腐植酸、褐煤转化过程的反应历程、反应机理以及反应动力学研究提供了一种新思路。
关键词 褐煤 化学族组成 组分分离法 分子水平
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Photoelectrode for water splitting: Materials,fabrication and characterization 被引量:6
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作者 Zhiliang Wang Lianzhou Wang 《Science China Materials》 SCIE EI CSCD 2018年第6期806-821,共16页
Photoelectorchemical(PEC) water splitting is an attractive approach for producing sustainable and environment-friendly hydrogen. An efficient PEC process is rooted in appropriate semiconductor materials, which shoul... Photoelectorchemical(PEC) water splitting is an attractive approach for producing sustainable and environment-friendly hydrogen. An efficient PEC process is rooted in appropriate semiconductor materials, which should possess small bandgap to ensure wide light harvest, facile charge separation to allow the generated photocharges migrating to the reactive sites and highly catalytic capability to fully utilize the separated photocharges. Proper electrode fabrication method is of equal importance for promoting charge transfer and accelerating surface reactions in the electrodes. Moreover,powerful characterization method can shed light on the complex PEC process and provide deep understanding of the rate-determining step for us to improve the PEC systems further. Targeting on high solar conversion efficiency, here we provide a review on the development of PEC water splitting in the aspect of materials exploring, fabrication method and characterization. It is expected to provide some fundamental insight of PEC and inspire the design of more effective PEC systems. 展开更多
关键词 PHOTOELECTRODE water splitting semiconductor material electrode fabrication CHARACTERIZATION
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Fractionation of Zn,Cd and Pb in a Tropical Soil After Nine-Year Sewage Sludge Applications 被引量:9
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作者 T.A.R.NOGUEIRA W.J.MELO +3 位作者 I.M.FONSECA S.A.MARCUSSI G.M.P.MELO M.O.MARQUES 《Pedosphere》 SCIE CAS CSCD 2010年第5期545-556,共12页
A long-term field experiment was carried out in the experiment farm of the Sao Paulo State University,Brazil,to evaluate the phytoavailability of Zn,Cd and Pb in a Typic Eutrorthox soil treated with sewage sludge for ... A long-term field experiment was carried out in the experiment farm of the Sao Paulo State University,Brazil,to evaluate the phytoavailability of Zn,Cd and Pb in a Typic Eutrorthox soil treated with sewage sludge for nine consecutive years,using the sequential extraction and organic matter fractionation methods.During 2005-2006,maize(Zea mays L.) was used as test plants and the experimental design was in randomized complete blocks with four treatments and five replicates.The treatments consisted of four sewage sludge rates(in a dry basis):0.0(control,with mineral fertilization),45.0,90.0 and 127.5 t ha-1,annually for nine years.Before maize sowing,the sewage sludge was manually applied to the soil and incorporated at 10 cm depth.Soil samples(0-20 cm layer) for Zn,Cd and Pb analysis were collected 60 days after sowing.The successive applications of sewage sludge to the soil did not affect heavy metal(Cd and Pb) fractions in the soil,with exception of Zn fractions.The Zn,Cd and Pb distributions in the soil were strongly associated with humin and residual fractions,which are characterized by stable chemical bonds.Zinc,Cd and Pb in the soil showed low phytoavailability after nine-year successive applications of sewage sludge to the soil. 展开更多
关键词 heavy metals humic substance sequential extraction Zea mays L.
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