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煤炭地下气化及对中国天然气发展的战略意义 预览
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作者 邹才能 陈艳鹏 +3 位作者 孔令峰 孙粉锦 陈姗姗 东振 《石油勘探与开发》 SCIE EI CAS CSCD 北大核心 2019年第2期195-204,共10页
基于国内外煤炭地下气化技术发展现状与趋势,提出了煤炭地下气化基本概念、机理与模式,指出目前面临的挑战、发展潜力与发展路径。煤炭地下气化这一革命性技术能够实现'人工制气',且符合煤炭清洁利用方向,在新能源达到规模化供... 基于国内外煤炭地下气化技术发展现状与趋势,提出了煤炭地下气化基本概念、机理与模式,指出目前面临的挑战、发展潜力与发展路径。煤炭地下气化这一革命性技术能够实现'人工制气',且符合煤炭清洁利用方向,在新能源达到规模化供应之前,可开辟中国特色的有效供甲烷与氢气战略新途径。中国含油气盆地煤系发育,仅超出煤炭企业井工开采深度、埋深1 000~3 000 m的煤炭资源量即为3.77×1012 t,初步预计可气化煤炭折合天然气资源量为(272~332)×1012m3,是常规天然气资源量的3倍,与非常规天然气资源量的总和基本相当。根据煤炭地下气化反应机理和产物组分的差别,初步将煤炭地下气化分为'浅层富氢、中深层富甲烷、深层超临界极富氢'3种开发模式。石油石化企业可在煤炭企业井工开采范围之外,发挥自身技术、管道、市场等一体化优势,根据不同需求和相应技术成熟度,优选路径发展煤炭地下气化业务,可将大量煤炭资源进行有效清洁开发利用,缓解天然气供应紧张局面,还可结合产出氢气就近利用以及在邻近油区开展CO2驱油与埋存,打造石油石化循环经济净零排放示范区,为'氢经济'时代到来储备资源和技术,更为中国'清洁、低碳、安全、高效'的现代能源体系建设开辟新的途径。 展开更多
关键词 煤炭 煤炭地下气化 天然气 天然气革命 人工煤制甲烷 人工煤制氢气 超临界水 超临界水煤气化制氢
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2018年煤炭供需形势分析及2019年展望 预览
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作者 肖新建 《中国能源》 2019年第2期9-12,共4页
2018年,煤炭先进产能释放加快,全国煤炭生产量和净进口量均较快增长,库存总体上升;在电力行业拉动作用下,煤炭消费呈现较强增长;全年煤炭价格稳定,煤炭企业经营形势稳中向好,煤炭采选业固定资产投资回暖。全国煤炭经济运行平稳,但数据... 2018年,煤炭先进产能释放加快,全国煤炭生产量和净进口量均较快增长,库存总体上升;在电力行业拉动作用下,煤炭消费呈现较强增长;全年煤炭价格稳定,煤炭企业经营形势稳中向好,煤炭采选业固定资产投资回暖。全国煤炭经济运行平稳,但数据显示供需存在较大缺口,需从供需两侧进行认真审视。展望2019年,全国煤炭需求增长不会如2018年乐观,煤炭生产有望进一步释放,煤炭供需将相对宽松。建议2019年完善相关制度,重点做好煤炭消费总量控制工作。 展开更多
关键词 煤炭 消费较强增长 价格稳定 供需两侧 控制总量
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我国块煤市场分析研究 预览
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作者 杨芊 《煤炭加工与综合利用》 CAS 2019年第4期75-80,I0001共7页
分析了全国煤炭市场现状,重点研究了2015年我国建筑陶瓷、耐火材料、玻璃、氧化铝、化工、兰炭、合成氨、民用8个领域的块煤消费情况;提出增加块煤生产将会给煤炭企业带来更多利润的建议,预测国内块煤消费市场将由2015年的3.91亿t,降低... 分析了全国煤炭市场现状,重点研究了2015年我国建筑陶瓷、耐火材料、玻璃、氧化铝、化工、兰炭、合成氨、民用8个领域的块煤消费情况;提出增加块煤生产将会给煤炭企业带来更多利润的建议,预测国内块煤消费市场将由2015年的3.91亿t,降低到“十三五”末期的3.46亿t以下。 展开更多
关键词 煤炭 块煤 市场分析 消费预测
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Quantitative hazard assessment for Zonguldak Coal Basin underground mines 预览
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作者 H.H.Erdogan H.S.Duzgun A.S.Selcuk-Kestel 《矿业科学技术学报:英文版》 CSCD 2019年第3期453-467,共15页
Underground coal mining is one of the most dangerous occupations throughout the world.The reasons behind an underground occupational accident are too complex to analyze mainly due to many uncertainties which may arise... Underground coal mining is one of the most dangerous occupations throughout the world.The reasons behind an underground occupational accident are too complex to analyze mainly due to many uncertainties which may arise from geological,operational conditions of the mine or individual characteristics of employees.This study proposes implementing a quantitative methodology for the analysis and assessment of hazards associated with occupational accidents.The application of the proposed approach is performed on the mines of Turkish Hard Coal Enterprises(TTK).The accidents in TTK between the years 2000 and 2014 are firstly statistically analyzed with respect to the number,type and location of accidents,age,experience,education level and main duty of the casualties and also injuries resulting from such accidents.The hazards are classified as individual,operational and locational hazards and quantified using contingency tables,conditional and total probability theorems.Lower and upper boundaries of hazards are determined and event trees for each hazard class are prepared.Total hazard evaluation results show that Armutcuk,Karadon and Uzulmez mines have relatively high hazard levels while Amasra and Kozlu mines have relatively lower hazard values. 展开更多
关键词 UNDERGROUND COAL mining OCCUPATIONAL accidents HAZARD assessment CONTINGENCY TABLES Zonguldak COAL Basin
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我国煤制燃料油技术进展及工业化现状 预览
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作者 胡发亭 颜丙峰 +2 位作者 王光耀 谷小会 常秋连 《洁净煤技术》 CAS 2019年第1期57-63,共7页
我国富煤贫油少气,以煤为原料生产清洁燃料油具有重要意义。为实现我国煤制燃料油产业健康有序快速发展,论述了煤直接液化、煤间接液化、煤油共炼3种煤制燃料油技术的定义、原理以及工艺流程,概述了煤制燃料油技术在我国的发展历程、技... 我国富煤贫油少气,以煤为原料生产清洁燃料油具有重要意义。为实现我国煤制燃料油产业健康有序快速发展,论述了煤直接液化、煤间接液化、煤油共炼3种煤制燃料油技术的定义、原理以及工艺流程,概述了煤制燃料油技术在我国的发展历程、技术研究进展及工业化应用现状。对3种煤制燃料油技工业应用过程中存在的问题、技术难点进行分析,并展望了应用前景。3种煤制燃料油技术在我国均已建成工业示范项目,步入了商业化发展阶段,煤直接液化和煤油共炼由于技术和原料的特殊性,目前均只是建设了一套工业示范装置,而我国已投产或试车成功的煤间接液化项目有10个左右,总产能近千万吨。煤直接液化技术吨油煤耗小,投资和运行成本低,今后应重点提高循环溶剂的质量和数量;煤间接液化技术成熟,是我国重点推广的煤制燃料油技术,未来的发展趋势是拓展产品种类,提高产品附加值;在同时具备适合液化的煤和重质油资源的企业适宜发展煤油共炼产业。国家应加大煤制油研发投入,重点解决目前存在的水耗、能耗、碳排放高等问题,并给予政策支持,促进煤制油产业快速发展,保障国家能源安全。以规划为先导,积极稳妥发展煤制燃料油产业,是煤炭行业未来发展的新格局新趋势。 展开更多
关键词 燃料油 直接液化 间接液化 煤油共炼
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微波辐射用于处理和开采岩石的研究进展 预览
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作者 杨兆中 朱静怡 +1 位作者 李小刚 刘紫微 《科学技术与工程》 北大核心 2019年第5期1-7,共7页
微波辐射具有加热速度快、选择性加热、体积式加热、易于控制、高效、安全等特点。针对目前岩石破碎高成本高能耗、煤层气和油页岩无法高效开发等缺点,详细介绍和评述了微波辐射在处理和开采岩石中的应用。分析表明,微波辐射可以在岩石... 微波辐射具有加热速度快、选择性加热、体积式加热、易于控制、高效、安全等特点。针对目前岩石破碎高成本高能耗、煤层气和油页岩无法高效开发等缺点,详细介绍和评述了微波辐射在处理和开采岩石中的应用。分析表明,微波辐射可以在岩石内部诱导产生热应力,进一步产生和延伸岩石内部的裂缝,从而达到预处理岩石和煤岩的作用;微波对煤岩有脱硫的作用;微波还可以加热煤层气和油页岩,帮助煤层气解析和油页岩的热解,从而对两种非常规油气资源进行原位开采。总结认为,精确描述不同岩石的介电特性、优化微波辐射的功率和时间、建立计算机数值模型并考虑化学反应的影响、研发大规模微波发生器下入井下是今后的发展方向。 展开更多
关键词 微波辐射 岩石 煤层气 油页岩
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煤泥浮选过程中粒度对泡沫性质的影响
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作者 谭佳琨 梁龙 +1 位作者 彭耀丽 谢广元 《中国矿业大学学报》 EI CAS CSCD 北大核心 2019年第1期195-203,共9页
针对复杂的三相浮选泡沫,探索了不同粒度煤炭颗粒在浮选过程中产率和灰分的变化规律及其对浮选泡沫性质的影响.将煤炭浮选入料分为粗(500~250μm)、中(250~74μm)、细(-74μm)3个粒级分别进行单独和混合浮选,在入料性质不同而操作条件... 针对复杂的三相浮选泡沫,探索了不同粒度煤炭颗粒在浮选过程中产率和灰分的变化规律及其对浮选泡沫性质的影响.将煤炭浮选入料分为粗(500~250μm)、中(250~74μm)、细(-74μm)3个粒级分别进行单独和混合浮选,在入料性质不同而操作条件相同的情况下,分析各粒级煤炭的浮选精煤产率和灰分,以及相应的浮选泡沫性质,包括水回收率、均一性(气泡尺寸)、破裂气泡尺寸、破裂气泡个数和泡沫速度等.结果表明:粗颗粒的浮选精煤产率明显受到细颗粒的影响,加入细颗粒后产率从30%升高到60%,但粗颗粒精煤灰分基本不变;细颗粒的浮选产率独立性好,基本不受粗颗粒和中颗粒的影响,但细颗粒精煤灰分随粗颗粒和中颗粒的加入而升高.通过对浮选泡沫性质的分析,发现粗颗粒促使气泡破裂并破坏泡沫的稳定性,中颗粒能够显著提高泡沫速度,而细颗粒能够增强泡沫稳定性并且降低泡沫速度.当浮选入料性质,即颗粒粒度改变时,各浮选泡沫性质与精煤灰分的相关性规律与入料性质不变而操作条件改变的常规浮选不同,主要是由不同粒度颗粒的特性差异所导致. 展开更多
关键词 浮选 泡沫特性 颗粒粒度 精煤灰分
Geophysical criterion of pre-outburst coal outsqueezing from the face space into the working 预览
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作者 Alexander Shadrin Yuliya Diyuk 《矿业科学技术学报:英文版》 CSCD 2019年第3期499-506,共8页
The initial process of coal and gas sudden outburst is studied in the article when under the influence of rock and gas pressure the part of a coal seam layer(a coal section)is squeezed out from the mouth of the future... The initial process of coal and gas sudden outburst is studied in the article when under the influence of rock and gas pressure the part of a coal seam layer(a coal section)is squeezed out from the mouth of the future outburst cavity in a jump-like manner into the working.Geo-mechanical criterion for a part of a coal seam layer outsqueezing in the form of the relation of active(squeezing out)and passive(preventing the outsqueezing)forces is defined in the article.Based on it,the geophysical criterion is defined by expressing basic physical parameters through geo-physical ones:the current stress is defined by spectral-acoustic method through the ratio of high frequency and low-frequency components of an acoustic signal,which is generated into a face working space by the mining equipment operating in the face;in-situ gas pressure is defined by gas analytical method by the concentration of methane in the atmosphere of the working;the strength of the most broken coal layer is defined by a strength measuring device(a device for measuring the depth of a steal cone punched into the coal by a spring mechanism).This paper studies the influence of acoustic,strength and filtrating and collecting properties of a face working space on the limit value of an obtained geophysical criterion of pre-outburst squeezing of a coal‘‘plug”out of the mouth of the future outburst cavity into the working. 展开更多
关键词 Block-like structure CRITERION of a COAL section outsqueezing Spectral-acoustic method Stress condition COAL strength property IN-SITU GAS pressure Aero and GAS control equipment METHANE concentration
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Mechanics of rib deformation—Observations and monitoring in Australian coal mines 预览
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作者 Yvette Heritage 《矿业科学技术学报:英文版》 CSCD 2019年第1期119-129,共11页
The risk of fatalities from rib failure is still prevalent in the coal mining industry. This risk has prompted further research to be conducted on rib deformation in order to understand the mechanisms of rib failure,w... The risk of fatalities from rib failure is still prevalent in the coal mining industry. This risk has prompted further research to be conducted on rib deformation in order to understand the mechanisms of rib failure,with the long-term objective being to improve rib support design. This paper presents the results of ACARP research project C25057, which investigated the mechanics and drivers of rib failure. The results of rib deformation monitoring at three different mines in Australia provide rib deformation characteristics for overburden depths ranging from 160 to 530 m. Monitoring includes deformation during development drivage conditions and during the longwall retreat abutment stress environment. The rib deformation monitoring covered three different seams: the Goonyella Middle Seam, Ulan Seam, and Bulli Seam in the Bowen Basin, Western Coalfield, and Southern Coalfield, respectively. The observed mechanisms driving the rib deformation ranged from bedding shear failure along weak claystone bands to vertical shear fractures to kinematic failures driven by shear failure dilation. The variation in mechanisms of rib failure, together with the seemingly consistent method of rib support design, prompts the question: what exactly is the role of rib support? 展开更多
关键词 Coal RIB DEFORMATION MONITORING Measurement
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A method to improve fluidization quality in gas-solid fluidized bed for fine coal beneficiation
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作者 Chenyang Zhou Xuchen Fan +1 位作者 Chenlong Duan Yuemin Zhao 《中国颗粒学报:英文版》 SCIE EI CAS CSCD 2019年第2期181-192,共12页
Dry coal separation has become essential in China because it does not consume water and it reduces environmental pollution. In this study, a method for improving fluidization quality in a fluidized bed separator using... Dry coal separation has become essential in China because it does not consume water and it reduces environmental pollution. In this study, a method for improving fluidization quality in a fluidized bed separator using a micropore sponge is proposed. The separator is used for fine coal beneficiation. The pressure drop across the distributor and bed fluidization characteristics were analyzed to evaluate fluidization quality. The beneficiation efficiency for fine coal was further investigated by using a laboratory-scale fluidized bed with and without a micropore sponge. With the sponge, the highest pressure drop fluctuation factor decreased from 0.23 to 0.16, indicating an improvement in density stability. The modified separation method reduced the ash content of a sample of fine coal from 23.83% to 10.70%. The probable error efficiency value E for -6 + 3 mm coal was 0.12g/cm^3, close to the efficiency error values reported for other dry-beneficiation techniques. The separation results show that using a sponge in the fluidized bed can readily improve the efficiency of fine coal beneficiation. 展开更多
关键词 Fluidized bed COAL BENEFICIATION MICROPORE SPONGE Fine COAL Dry separation DISTRIBUTOR
洪塘煤矿煤中微量和稀土元素的地球化学特征 预览
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作者 胡小娟 夏小进 +2 位作者 黄懿 邹勇军 米振华 《江西煤炭科技》 2019年第1期11-14,共4页
对洪塘煤矿乐平组主采煤层中微量元素和稀土元素的地球化学特征分析研究结果表明,煤中微量元素的平均含量高于中国煤的平均值,亦高于世界煤的平均值;与地壳的平均含量相比,煤中比较富集的元素有Ge、U、As。稀土元素含量为高于中国陆壳... 对洪塘煤矿乐平组主采煤层中微量元素和稀土元素的地球化学特征分析研究结果表明,煤中微量元素的平均含量高于中国煤的平均值,亦高于世界煤的平均值;与地壳的平均含量相比,煤中比较富集的元素有Ge、U、As。稀土元素含量为高于中国陆壳稀土元素总量均值和世界煤中稀土元素总量均值,低于中国煤中稀土元素总量均值;稀土元素分布模式基本一致,均呈左高右低的宽缓"V"型曲线。 展开更多
关键词 微量元素 稀土元素 地球化学特征
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Subsidence over room and pillar retreat mining in a low coal seam 预览
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作者 Andre Zingano Anderson Weiss 《矿业科学技术学报:英文版》 CSCD 2019年第1期51-57,共7页
The objective of this paper is to study the behavior of a low thick and low depth coal seam and the overburden rock mass. The mining method is room and pillar in retreat and partial pillar recovery. The excavation met... The objective of this paper is to study the behavior of a low thick and low depth coal seam and the overburden rock mass. The mining method is room and pillar in retreat and partial pillar recovery. The excavation method is conventional drill and blast because of the small production. The partial pillar recovery is about 30% of the previous pillar size, 7 m × 7 m. The roof displacement was monitored during retreat operation;the surface movement was also monitored. The effect of the blasting vibration on the final pillar strength had been considered. Due to blasting, the pillar reduced about 20%. The consequence is more pillar deformation and roof vertical displacement. The pillar retreat and ground movement were simulated in a three-dimensional numerical model. This model was created to predict the surface subsidence and compare to the subsidence measured. This study showed that the remaining pillar and low seam reduce the subsidence that was predicted with conventional methods. 展开更多
关键词 SUBSIDENCE Room-and-pillar MINING RETREAT MINING Coal
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动静组合加载下煤体损伤及力学特性研究
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作者 杨英明 陶春梅 +1 位作者 郭奕宏 张科学 《采矿与安全工程学报》 EI CSCD 北大核心 2019年第1期198-206,共9页
为了揭示动力扰动下煤体的冲击失稳机理,对动静组合加载下煤体损伤机制及力学响应特征进行定性研究。首先进行冲击矿井煤体力学性质测定试验,继而运用RFPA2D-DynamicStatic软件模拟分析了静力水平和动力扰动波形对煤体裂隙发育、损伤单... 为了揭示动力扰动下煤体的冲击失稳机理,对动静组合加载下煤体损伤机制及力学响应特征进行定性研究。首先进行冲击矿井煤体力学性质测定试验,继而运用RFPA2D-DynamicStatic软件模拟分析了静力水平和动力扰动波形对煤体裂隙发育、损伤单元分布及声发射特征的影响,研究了动力扰动对煤体力学性能和能量演化特征的影响。研究结果表明:(1)动静组合加载下,煤体抗压强度与损伤度呈线性负相关性,弹性能储能极限与损伤度呈负指数关系。(2)在动力扰动作用下,煤体内部损伤不断加剧,煤体弹性能储能极限以[]13.71ln 36.33eU (28)-D (10)的趋势不断降低,冲击破坏损耗能不断减少,原本积聚在煤体内的弹性能会瞬间释放,导致煤体冲击破坏。(3)提出了增加煤柱的抗扰动能力和减少煤体中积聚的弹性能2种防治震动型冲击地压措施。 展开更多
关键词 动静组合加载 煤体 损伤 力学特性 冲击地压
Effect of weathering on physico-chemical properties and combustion behavior of an Indian thermal coal 预览
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作者 Subhajit Aich Barun Kumar Nandi Sumantra Bhattacharya 《国际煤炭科学技术学报:英文版》 2019年第1期51-62,共12页
An open air stockpile of conical shape was formed with 3.5 m base diameter and 5 m height using 500 tons of -200 mm size ROM thermal coal on a concrete floor. Coal sample from the stockpile were collected at 30 days i... An open air stockpile of conical shape was formed with 3.5 m base diameter and 5 m height using 500 tons of -200 mm size ROM thermal coal on a concrete floor. Coal sample from the stockpile were collected at 30 days interval for analysis of various chemical properties like;proximate analysis, ultimate analysis, gross calorific value (GCV) and various combustion related properties such as ignition temperature, peak temperature, burnout temperature, maximum combustion rate, ignition index, burnout index, combustion performance index and combustion rate intensity index. Experimental results show that, due to weathering of coal fixed carbon decreased from 35.6% to 19.9%, elemental carb on (C) decreased from 46.6% to 28.6%, hydrogen (H) decreased from 3.3% to 2.9% and GCV decreased by up to 55% of original value during 330 days of storage of coal in an open atmosphere. Ash con tent of coal increased form 29.2% to 46.6% due to loss of combustibles. Sulfur (S) of coal was found to get increased from 0.33% to 1.08% during storage. The activation energy of coal combustion increased from 22 kJ/mol to 54 kJ/mol. Variation in combustion parameters signifies that weathering has significant negative impact on coal combustion properties as coal become difficult to ignite. 展开更多
关键词 WEATHERING of COAL TGA-DTG Combustibles COAL COMBUSTION Activation energy
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压汞法研究煤孔隙的适用性与局限性探讨 预览
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作者 刘长江 桑树勋 +1 位作者 张琨 宋璠 《实验室研究与探索》 CAS 北大核心 2019年第3期11-15,共5页
为探讨压汞法在煤孔隙研究过程中的适用性和局限性,以褐煤、气肥煤、瘦煤、无烟煤4种不同煤级以及无烟煤的4种不同粒度煤样品为研究对象,通过对压汞数据的分形维数特征讨论认为:煤的压汞过程可以明显分为前进汞阶段、进汞阶段以及后进... 为探讨压汞法在煤孔隙研究过程中的适用性和局限性,以褐煤、气肥煤、瘦煤、无烟煤4种不同煤级以及无烟煤的4种不同粒度煤样品为研究对象,通过对压汞数据的分形维数特征讨论认为:煤的压汞过程可以明显分为前进汞阶段、进汞阶段以及后进汞阶段3个阶段。结果表明,在应用压汞仪对煤样品进行孔隙分析及数据处理时,不能直接进行煤的全孔径分析,而应充分考虑到前进汞阶段和后进汞阶段对压汞数据的影响。 展开更多
关键词 压汞法 粒间孔 煤的压缩性
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Prediction of coal structure using particle size characteristics of coalbed methane well cuttings 预览
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作者 Shuaifeng Lv Shengwei Wang +3 位作者 Rui Li Guoqing Li Ming Yuan Jiacheng Wang 《矿业科学技术学报:英文版》 CSCD 2019年第2期209-216,共8页
Severely deformed coal seams barely deliver satisfactory gas production.This research was undertaken to develop a new method to predict the positions of deformed coals for a horizontal CBM well.Firstly,the drilling cu... Severely deformed coal seams barely deliver satisfactory gas production.This research was undertaken to develop a new method to predict the positions of deformed coals for a horizontal CBM well.Firstly,the drilling cuttings of different structure coals were collected from a coal mine and compared.In light of the varying cuttings characteristics for different structure coals,the coal structure of the horizontally drilled coal seam was predicted.And the feasibility of this prediction method was discussed.The result shows that exogenetic fractures have an important influence on the deformation of coal seams.The hardness coefficient of coal decreases with the deformation degree in the order of primary structural,cataclastic and fragmented coal.And the expanding-ratio of gas drainage holes and the average particle size of cuttings increase with the increase of the deformation degree.The particle size distribution of coal cuttings for the three types of coals is distinctive from each other.Based on the particle size distribution of cuttings from X-2 well in a coal seam,six sections of fragmented coal which are unsuitable for perforating are predicted.This method may benefit the optimization of perforation and fracturing of a horizontal CBM well in the study area. 展开更多
关键词 COAL structure Gas drainage BOREHOLES Particle size distribution of COAL CUTTINGS Directional CBM WELL Optimization of PERFORATION
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不同变质程度煤成焦后焦炭的光学组织与冷热性能研究 预览
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作者 郭德英 李东涛 +3 位作者 张小明 马超 代鑫 刘洋 《首钢科技》 2019年第2期10-15,34共7页
测试了30余种炼焦煤的镜质体最大反射率以及成焦后焦炭的光学组织和冷热性能,并研究了二者之间的相互关系。结果表明,焦炭的光学组织随炼焦煤的变质程度呈现规律性变化,焦炭的冷热性能和光学组织含量之间可以建立回归方程,用于指导炼焦... 测试了30余种炼焦煤的镜质体最大反射率以及成焦后焦炭的光学组织和冷热性能,并研究了二者之间的相互关系。结果表明,焦炭的光学组织随炼焦煤的变质程度呈现规律性变化,焦炭的冷热性能和光学组织含量之间可以建立回归方程,用于指导炼焦生产后,经济效益显著。 展开更多
关键词 炼焦煤 镜质体最大反射率 焦炭的光学组织 焦炭质量
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贵州省燃煤污染型地方性氟中毒历史重病区村16周岁以上人群总摄氟量调查分析
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作者 张伯友 张念恒 +1 位作者 李杨 安冬 《中华地方病学杂志》 CAS CSCD 北大核心 2019年第1期41-44,共4页
目的 了解贵州省燃煤污染型地方性氟中毒(简称燃煤型氟中毒)历史重病区综合防治后16周岁以上人群总摄氟量现状。 方法 2017年,选择历史病情较重且未达到病区消除标准的荷花村、吉丰村和吉坪村作为调查点。对3个村全部8-12周岁在校学生... 目的 了解贵州省燃煤污染型地方性氟中毒(简称燃煤型氟中毒)历史重病区综合防治后16周岁以上人群总摄氟量现状。 方法 2017年,选择历史病情较重且未达到病区消除标准的荷花村、吉丰村和吉坪村作为调查点。对3个村全部8-12周岁在校学生进行氟斑牙患病情况检查;每村抽取10户居民户,调查16周岁以上人群平均每人每天的主食、蔬菜、水摄入量,并采集其家中食用玉米、大米、干辣椒、饮用水、室内空气样品,检测氟含量,计算人群总摄氟量。并将调查结果与2006年调查数据进行比较。 结果 荷花、吉丰、吉坪3个村8-12周岁儿童氟斑牙检出率分别为16.86%(29/172)、17.90%(29/162)、7.94%(10/126),与来自文献的2006年[94.32%(216/229)、100.00%(72/72)、99.63%(267/268)]比较差异均有统计学意义(χ^2 = 247.97、136.95、345.13,P均< 0.01);氟斑牙指数分别为0.36、0.40、0.12。3个村居民饮用水氟含量中位数分别为0.040、0.029、0.033 mg/L;主食大米的氟含量中位数分别为0.019、0.016、0.015 mg/kg,与2006年(主食为玉米,17.520、36.620、27.770 mg/kg)比较分别降低了99.89%、99.96%、99.95%;干辣椒氟含量中位数分别为2.09、1.97、0.35 mg/kg,与2006年(514.21、1 035.29、947.78 mg/kg)比较,分别降低了99.59%、99.81%、99.96%,二者比较差异均有统计学意义(Z= 2.079、2.542、2.449,P均< 0.01);室内24 h空气样均未检出氟化物。3个村16周岁以上人群平均每人每日摄氟量为0.304、0.279、0.273 mg,与2006年(19.564、33.837、27.224 mg)比较,分别降低了98.45%、99.18%、99.00%。 结论 贵州省燃煤型氟中毒历史重病区,16周岁以上人群总摄氟水平显著降低。 展开更多
关键词 氟中毒 总摄氟量
Arbuscular mycorrhizal fungi ameliorate the chemical properties and enzyme activities of rhizosphere soil in reclaimed mining subsidence in northwestern China
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作者 QIU Lang BI Yinli +3 位作者 JIANG Bin WANG Zhigang ZHANG Yanxu Yryszhan ZHAKYPBEK 《干旱区科学:英文版》 SCIE CSCD 2019年第1期135-147,共13页
In semi-arid region of northwestern China, underground mining subsidence often results in decreased vegetation coverage, impoverishment of soil fertility and water stress. In addition, the physical-chemical and biolog... In semi-arid region of northwestern China, underground mining subsidence often results in decreased vegetation coverage, impoverishment of soil fertility and water stress. In addition, the physical-chemical and biological properties of soil also change, resulting in more susceptible to degradation. In particular, subsidence causes disturbance of the symbioses of plant and microbe that can play a beneficial role in the establishment of vegetation communities in degraded ecosystems. The objective of this study was to evaluate the effects of revegetation with exotic arbuscular mycorrhizal fungi(AMF) inoculum on the chemical and biological properties of soil over time in mining subsidence areas. Soils were sampled at a depth up to 30 cm in the adjacent rhizosphere of Amorpha fruticose Linn. from five reclaimed vegetation communities in northwestern China. In August 2015, a field trial was set up with five historical revegetation experiments established in 2008(7-year), 2011(4-year), 2012(3-year), 2013(2-year) and 2014(1-year), respectively. Each reclamation experiment included two treatments, i.e., revegetation with exotic AMF inoculum(AMF) and non-AMF inoculum(the control). Root mycorrhizal colonization, glomalin-related soil protein(GRSP), soil organic carbon(SOC), soil nutrients, and enzyme activities were also assessed. The results showed that mycorrhizal colonization of inoculated plants increased by 33.3%–163.0% compared to that of non-inoculated plants(P<0.05). Revegetation with exotic AMF inoculum also significantly improved total GRSR(T-GRSP) and easily extracted GRSP(EE-GRSP) concentrations compared to control, besides the T-GRSP in 1-year experiment and the EE-GRSP in 2-year experiment. A significant increase in SOC content was only observed in 7-year AMF reclaimed soils compared to non-AMF reclaimed soils. Soil total N(TN), Olsen phosphorus(P) and available potassium(K) were significantly higher in inoculated soil after 1–7 years of reclamation(except for individual cases), and increased with reclamat 展开更多
关键词 REVEGETATION MYCORRHIZAL COLONIZATION glomalin-related soil proteins ARBUSCULAR MYCORRHIZAL fungi coal mining Amorpha fruticose
对我国煤炭利用转型发展浅析 预览
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作者 侯志鹰 《当代石油石化》 CAS 2019年第2期43-47,共5页
针对我国实际情况,结合能源禀赋特点,分析了我国化石能源尤其是煤炭资源概况,阐述了煤炭利用转型的内在原因和外在因素,探讨我国煤炭目前的能源主体地位以及今后转型发展的有效途径,论述煤炭的清洁高效利用是必经之路,可再生能源替代化... 针对我国实际情况,结合能源禀赋特点,分析了我国化石能源尤其是煤炭资源概况,阐述了煤炭利用转型的内在原因和外在因素,探讨我国煤炭目前的能源主体地位以及今后转型发展的有效途径,论述煤炭的清洁高效利用是必经之路,可再生能源替代化石能源是必然趋势,运用煤炭本身所具有的燃料(能源)和原料(材料)双重属性的特点,提出了未来煤炭利用的新方向。 展开更多
关键词 煤炭 转型发展 化石能源 可再生能源 清洁利用
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