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Investigation of the medium calcium based non-burnt brick made by red mud and fly ash: durability and hydration characteristics 被引量:10
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作者 Ying-tang Xu Bo Yang +4 位作者 Xiao-ming Liu Shuai Gao Dong-sheng Li Emile Mukiza Hua-jian Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2019年第8期983-991,共9页
Red mud is a type of highly alkaline waste residue produced in the process of alumina smelting by the Bayer process.Based on the idea of medium calcium content,solid wastes such as red mud and fly ash were used to pre... Red mud is a type of highly alkaline waste residue produced in the process of alumina smelting by the Bayer process.Based on the idea of medium calcium content,solid wastes such as red mud and fly ash were used to prepare non-burnt bricks;and the mass ratio of CaO/SiO2 was selected in the range of 0.88–1.42.Mechanical properties and durability were investigated with a compressive strength test.X-ray diffractometry(XRD),scanning electron microscope(SEM),and Fourier transform infrared spectroscopy(FTIR)techniques were used to characterize the hydration characteristic.The environmental performance was analyzed by Inductively Coupled Plasma Mass Spectrometry(ICP).The results indicated that the mechanical properties and the durability were optimal when the mass ratio of CaO/SiO2 was 1.23.The hydration products were mostly C–S–H gel,ettringite,Na4Ca(Si10All6)O32·12H2O and Ca3Al2(SiO4)(OH)8.They were responsible for the strength development,and the CaO/SiO2 mass ratio of 1.23 had the best polymerized structure.The results of an environmental performance test showed that the heavy metals in the raw materials were well-solidified in the brick.Therefore,this paper provides an effective solution for use of solid wastes in building material. 展开更多
关键词 MEDIUM CALCIUM content red MUD fly ash non-burnt BRICK
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An improved algorithm for mapping burnt areas in the Mediterranean forest landscape of Morocco 被引量:1
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作者 Issameddine Zidane Rachid Lhissou +1 位作者 Abdelali Bouli Mustapha Mabrouki 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第3期981-992,共12页
The identification of burnt forests and their monitoring provide essential information for the suitable management and conservation of these ecosystems. This research focuses on the use of remote sensing with MODIS se... The identification of burnt forests and their monitoring provide essential information for the suitable management and conservation of these ecosystems. This research focuses on the use of remote sensing with MODIS sensor data in a Mediterranean environment, precisely in the Rif region known for its high occurrence of forest fires and the largest burnt areas in Morocco. It mapped the burnt areas during the summer of 2016 using spectral indices from MODIS images, namely the Normalized Burn Ratio (NBR) and the Burnt Area Index for MODIS (BAIM). Two field surveys were used to calibrate spectral indices and validate the maps. First, a monotemporal analysis using a single pre-fire image determined the appropriate threshold of the spectral indices (BAIM and NBR) for burn detecting. Secondly, a multitemporal method was applied based on dBAIM and dNBR images which represented pre-fire and postfire differences of the BAIM and NBR images, respectively. The results show that separate use of monotemporal postfire and multitemporal methods produced an overestimation of the burnt areas. Finally, we propose a new algorithm combining both methods for burnt area mapping that we name Burnt Area Algorithm. MCD45A1 and MCD64A1 MODIS burnt area products were compared to the proposed algorithm. Validation of the estimated burnt areas using reference data of the Moroccan High Commission for Water, Forests and Fight against Desertification showed satisfactory results using the proposed algorithm, with a determination coefficient of 0.68 and a root mean square error of 44.0 ha. 展开更多
关键词 burnt FOREST MAPPING THRESHOLD MODIS MCD45A1 MCD64A1 SPECTRAL indices Morocco
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Petrologic and REE Geochemical Characters of Burnt Rocks 被引量:1
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作者 HUANG Lei LIU Chiyang YANG Lei ZHAO Junfeng FANG Jianjun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第2期392-398,共7页
The study of burnt rocks is beneficial to the discussion on the tectonic movement, paleoclimate and paleogeography that coal seams are subjected to after they were formed. In order to obtain the basic data on the feat... The study of burnt rocks is beneficial to the discussion on the tectonic movement, paleoclimate and paleogeography that coal seams are subjected to after they were formed. In order to obtain the basic data on the features of the burnt rocks, a systematic study of petrology and REE geochemistry on burnt rocks in Shenmu, Northern Shaanxi Province has been done, using the methods of SEM, EDS, susceptibility measurements and ICP-MS. The burnt rocks are divided into two series in the section: the melted rocks and the baked rocks. SEM and EDS analyses reveal that all the minerals show burnt and melted traces, and there are no clay minerals except illite found in the burnt rocks. Susceptibility measurements reveal that the burnt rocks have abnormally high susceptibility values, whereas a geochemical analysis shows that the REE distribution pattern of burnt rocks is similar to that of sedimentary rocks (initial rocks). In the longitudinal section, with increasing degree of burning (from baked rocks to melted rocks), the ∑REE gradually decreases, and the total REE of melted rocks is obviously lower than that of baked rocks. Besides, the melted rocks show apparent negative Ce anomalies, while the baked rocks show no anomaly of Ce, and sometimes even show positive anomalies. 展开更多
关键词 burnt rock mineral petrology SUSCEPTIBILITY REE negative Ce anomaly
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Sensitive Evaluation on Early Cracking Tendency of Concrete with Inclusion of Light-burnt MgO 被引量:3
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作者 陈霞 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2011年第5期1018-1022,共5页
The advanced temperature and stress test machine was introduced to determine the early cracking tendency of concrete with inclusion of light-burnt MgO under full restraint by tracking the development of thermal,physic... The advanced temperature and stress test machine was introduced to determine the early cracking tendency of concrete with inclusion of light-burnt MgO under full restraint by tracking the development of thermal,physical and deformation properties.Results showed that light-burnt MgO being incorporated ranging between 4 wt% and 6 wt% of cementitious materials was beneficial to increase the maximum compressive stress and cracking stress of concrete by 0.37 MPa and 0.2 MPa on average respectively.The second zero stress temperature was reduced by 11.4 ℃ and the maximum temperature was slightly reduced while cracking thermal impact was significantly enhanced from 59.8 ℃ to 66.2 ℃.Sensitive anti-cracking coefficient F was forwarded to assess the early cracking tendency of concrete and the inclusion of 4 wt% light-burnt MgO with activity of 109 s ranked the best in crack resistance. 展开更多
关键词 crack resistance cracking stress light-burnt MgO CONCRETE sensitive evaluation
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Temperature field distribution of burnt surrounding rock in UCG stope 被引量:10
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作者 Xin Lin Wang Zuotang +4 位作者 Huang Wengang Kang Guojun Lu Xuefeng Zhang Peng Wang Jianhua 《International Journal of Mining Science and Technology》 SCIE EI 2014年第4期573-580,共8页
In order to study temperature field distribution in burnt surrounding rock and to determine ranges of burnt surrounding rock, coal-wall coking cycle and heat influence in the underground coal gasification(UCG) stope, ... In order to study temperature field distribution in burnt surrounding rock and to determine ranges of burnt surrounding rock, coal-wall coking cycle and heat influence in the underground coal gasification(UCG) stope, based on the Laplace transform and inversion formula, we studied the temperature analytical solution of one-dimensional unsteady heat conduction for multi-layer overlying strata under the first and the forth kinds of boundary conditions, and we also carried out a numerical simulation of twodimensional unsteady heat conduction by the COMSOL multiphysics. The results show that when the boundary temperature of surrounding rock has a linear decrease because of a directional movement of heat source in the UCG flame working face, the temperature in surrounding rock increases first and then decreases with time, the peak of temperature curve decreases gradually and its position moves inside surrounding rock from the boundary. In the surrounding rock of UCG stope, there is an envelope curve of temperature curve clusters. We analyzed the influence of thermophysical parameters on envelope curves and put forward to take envelope curve as the calculation basis for ranges of burnt surrounding rock, coal-wall coking cycle and heat influence. Finally, the concrete numerical values are given by determining those judgement standards and temperature thresholds, which basically tally with the field geophysical prospecting results. 展开更多
关键词 Underground coal gasification (UCG) Temperature distribution Laplace transform Envelope curve burnt surrounding rock Coking cycle
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Forest structure, diversity and regeneration in unburnt and burnt Anogeissus latifolia forests in Garhwal Himalayas
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作者 Munesh KUMAR Jahangeer A. BHAT G. S. RAJWAR 《Forestry Studies in China》 CAS 2012年第4期268-275,共8页
The present study was carried out at two different gradients of unbumt and burnt Anogeissus latifolia forest sites in the Garhwal region, India. At each gradient, the unburnt and burnt forest sites were further catego... The present study was carried out at two different gradients of unbumt and burnt Anogeissus latifolia forest sites in the Garhwal region, India. At each gradient, the unburnt and burnt forest sites were further categorized into three different elevations, i.e., lower (700 m), middle (850 m) and upper (1000 m). At each elevation, the density of trees, saplings and seedlings was higher at the unburnt sites except for trees at the upper elevation which was higher at the burnt sites. The total basal area of each layer of for- est was also higher at the unburnt sites. The study revealed that the lower number of saplings and seedlings at the burnt forest sites might be due to the effect of fire. Most trees in the lower dbh classes were affected by forest fire at the burnt sites which reduced the total density and total basal area of the trees compared to the unburnt sites. The diversity of trees increased with increasing elevation. However, the diversity of saplings and seedlings reduced with increasing elevation. 展开更多
关键词 Anogeissus latifolia unburnt and burnt forest elevational gradient DIVERSITY REGENERATION
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Adult with mass burnt lime aspiration: A case report and literature review
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作者 Xin-Yu Li Hai-Jia Hou +2 位作者 Bing Dai Wei Tan Hong-Wen Zhao 《World Journal of Clinical Cases》 SCIE 2021年第32期9935-9941,共7页
BACKGROUND Foreign body aspiration mainly occurs in children,which can cause a severe concurrent syndrome and even death without timely treatment.As a rare foreign body,aspiration of lime is seldom reported,and most c... BACKGROUND Foreign body aspiration mainly occurs in children,which can cause a severe concurrent syndrome and even death without timely treatment.As a rare foreign body,aspiration of lime is seldom reported,and most cases involve a small amount of hydrated lime.Although the symptoms are usually severe,the prognosis is good after suitable treatment.Experience of treatment for lime aspiration is lacking,and this report provides novel evidence for treatment of mass burnt lime aspiration using bronchoscopy.CASE SUMMARY We report an adult with a large amount of burnt lime aspiration.Because of delay in clearance of the inhaled lime in the trachea and bronchus at the local hospital,he suffered several severe complications,including complete occlusion of the right primary bronchus,aeropleura,aerodermectasia,pneumomediastinum,secondary infection and hypoxemia at 4 d after injury.After transferring to our department,bronchoscopy was immediately carried out to clear the lime in the major airway,using foreign body forceps,biopsy forceps,puncture needle,and hairbrush.The patient’s condition recovered rapidly and at 3-months’follow-up,he demonstrated good recovery of the bronchus and lung parenchyma.CONCLUSION After mass lime aspiration,flexible fiberoptic bronchoscopy is suggested as early as possible,using clamping,flushing or cryotherapy. 展开更多
关键词 burnt lime ASPIRATION Bronchial obstruction Flexible fiberoptic bronchoscopy Computed tomography Case report
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Distributions of rare-earth elements in two Chinese coals and their burnt products
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作者 姚多喜 支霞臣 《Journal of Coal Science & Engineering(China)》 2005年第2期71-74,共4页
The concentrations of two fresh Chinese coals (lignitie and fatty coal ) from dif-ferent geological origin and the corresponding fly and bottom ashes were determined us-ing inductively coupled plasma mass spectrometry... The concentrations of two fresh Chinese coals (lignitie and fatty coal ) from dif-ferent geological origin and the corresponding fly and bottom ashes were determined us-ing inductively coupled plasma mass spectrometry(ICP-MS). The ranges and means of concentrations of these elemennts were given. Based on the combustion simulating ex-periment in the one-dismensional boiler, the contents of REE (rare-earth element) of 18 samples in lignite, fatty coal and their fly and bottom ashes in different combustion condi-tion were determined, and geochemical feature of REE were analyzed. 展开更多
关键词 REE DISTRIBUTION burnt products coal combustion two Chinese coals
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“Burnt-Out” Endomyocardial Fibrosis—An Overview
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作者 Ramachandran Muthiah 《Case Reports in Clinical Medicine》 2016年第11期437-493,共57页
Tropical endomyocardial fibrosis (EMF) is a public health problem affecting the children, young adults and elderly individuals in an epidemic fashion in the coastal districts of south India. Due to lack of resources f... Tropical endomyocardial fibrosis (EMF) is a public health problem affecting the children, young adults and elderly individuals in an epidemic fashion in the coastal districts of south India. Due to lack of resources for research in these endemic areas, its etiology remains elusive and hypotheses ranging from infections and allergic causes to malnutrition and toxins have not been tested rigorously. The disease is characterized by endocardial fibrosis and the right ventricle is the cardiac chamber most frequently affected. Patients may present clinically with heart failure and an associated AV (atrioventricular) valve regurgitation is common. Several features of the advanced disease called as “burnt-out” stage of endomyocardial fibrosis (EMF) are not fully understood. Background of these case studies described the clinical presentation, echocardiographic features and management of this late stage of the disease. 展开更多
关键词 Endomyocardial Fibrosis burnt-Out Stage Pericardial Effusion Endocardial Calcification “Cobra-Head” Fibrosis
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基于Landsat影像评估鸡足山火烧迹地近40年植被恢复动态
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作者 苏维翰 张楚然 +6 位作者 邓云 翟德利 张明达 李生发 李逢昌 唐志忠 林露湘 《生态学报》 北大核心 2025年第3期1362-1378,共17页
大范围、高强度的森林火灾能够摧毁地表植被并重启群落演替进程,是影响滇中地区森林生态系统稳定的重要干扰因素之一,但当地这些火烧事件的干扰边界和随后的植被恢复动态目前仍缺乏足够的定量报道。以大理鸡足山亚热带半湿润常绿阔叶林... 大范围、高强度的森林火灾能够摧毁地表植被并重启群落演替进程,是影响滇中地区森林生态系统稳定的重要干扰因素之一,但当地这些火烧事件的干扰边界和随后的植被恢复动态目前仍缺乏足够的定量报道。以大理鸡足山亚热带半湿润常绿阔叶林分布区内1984年5月3日发生火灾的火烧迹地为主要研究对象,基于1986-2023年的Landsat多时序影像,尝试以差值归一化燃烧指数(difference Normalized Burn Ratio,dNBR)对当地历史火烧事件的火烈度边界进行定量划分,以地形因子和多重比较对不同火烈度区域间空间分布格局差异进行解释和分析;以植被覆盖度(Fractional Vegetation Cover,FVC)、归一化燃烧指数(Normalized Burn Ratio,NBR)和燃烧恢复率(Burn Recovery Ratio,BRR)等遥感植被指数时序变化和分段线性回归模型对火烧迹地上的植被恢复阶段进行定量区分,结合气温和降水等气候因子的时序变化对植被恢复过程中的重要时间拐点进行解释,并以林冠高度特征对火烧迹地目前的植被恢复程度进行评价。研究结果表明:当地1984年时的总过火面积应不小于1423.71 hm^(2),火烧迹地可划分为轻度、中低度、中高度和重度等四个火烈度(Fire severity)等级,面积比例分别为63.39%、30.73%、5.85%和0.03%,坡度较小则火烈度可能越高;轻度和中低度火烈度区可分为快速恢复(1986-1996年)和降速恢复阶段(1996年至今),中高度和重度火烈度区可分为快速恢复(1986-1990年)、降速恢复(1990-1996年)和稳定(1996年至今)阶段,但气候因子并未表现出类似的阶段性变化,遥感植被指数的时间动态更多与植被演替过程中的树种迭代过程有关;各火烈度区域内的林冠平均高度至今仍较对照区(26.4 m)偏低,林冠结构和森林地上生物量应仍处于恢复过程中。当地火烧迹地上的森林经过40年的恢复后应仍处于次生演替的前中期,亚热带半湿润常绿阔叶林的恢复是一个复杂且长期的过程。 展开更多
关键词 卫星遥感 多光谱 火烈度 火烧迹地 植被恢复
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Disaster victim identification operations with fragmented,burnt,or commingled remains:experience-based recommendations 被引量:3
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作者 Hans H.de Boer Julie Roberts +2 位作者 Tania Delabarde Amy Z.Mundorff Soren Blau 《Forensic Sciences Research》 CSCD 2020年第3期191-201,共11页
Human-made and natural disasters can result in severely fragmented,compromised,and commingled human remains.The related disaster victim identification(DVI)operations are invariably challenging,with the state of the re... Human-made and natural disasters can result in severely fragmented,compromised,and commingled human remains.The related disaster victim identification(DVI)operations are invariably challenging,with the state of the remains potentially precluding some identifications.Practitioners involved in these DVI operations will routinely face logistical,practical,and ethical challenges.This review provides information and guidance derived from firsthand experiences to individuals tasked with managing DVI operations with fragmented human remains.We outline several key issues that should be addressed during disaster preparedness planning and at the outset of an operation,when incident-specific strategies are developed.Specific challenges during recovery and examination of fragmented remains are addressed,highlighting the importance of experienced specialists at the scene and in the mortuary.DNA sample selection and sampling techniques are reviewed,as well as downstream effects of commingling and contamination,which can complicate reconciliation and emphasise the need for rigorous quality control.We also touch on issues that may arise during communication with families.While recommendations are provided,they are not intended as proscriptive policy but rather as an addition to the general recommendations given in the International Criminal Police Organization(INTERPOL)DVI Guide,to inform preparative discussions between government officials,judiciary,police,and forensic specialists. 展开更多
关键词 Forensic sciences forensic anthropology DVI fragmented human remains burnt commingled DNA
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Preparation and Metallurgical Analysis of High Activity Burnt Lime for Steelmaking 被引量:1
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作者 Hua-qiang HAO Yu-zhu ZHANG +3 位作者 Su-ju HAO Chao-fa ZHANG Wu-feng JIANG Peng-hui CUI 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2016年第9期884-890,共7页
Burnt lime is an important material in steelmaking and its activity degree is a key factor for liquid steel quality. The burnt lime was made by the calcination of limestone in a high pressure electric furnace. The bur... Burnt lime is an important material in steelmaking and its activity degree is a key factor for liquid steel quality. The burnt lime was made by the calcination of limestone in a high pressure electric furnace. The burnt lime mineralogical phases and micro-morphologies were characterized by X-ray diffraction (XRD) and field emission scan- ning electron microscopy (FE-SEM). The burnt lime activity degree was determined by acid-base titration, the burnt lime pore distribution was measured by mercury intrusion porosimetry (MIP), and the thermal effect of a mixture of burnt lime and slag was measured by differential scanning calorimetry (DSC). The results showed that the CaO grain size and pore size of burnt lime made under high pressure were larger than those of burnt lime made under atmos- pheric pressure. The CaO grain size and pore size increased and the laminate phenomenon also occurred clearly under high pressure. The activity degree of burnt lime made under high pressure was greater than that made under atmos- pheric pressure. The maximum activity degree was 437 mL for burnt lime made under a pressure of 0.4 MPa. For the same ratio of CaO to SiOz, the melting temperature, hemisphere temperature and fluidity temperature of slag decreased with increasing burnt lime activity degree. The higher the activity degree the burnt lime had, the better the slag forming occurred. It was advantageous for -2CaO · SiO2 and 3CaO · SiO2 forming at lower temperatures if the burnt lime activity degree was increased. 展开更多
关键词 burnt lime high pressure calcination activity degree physical property slag performance
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干湿循环作用烧变岩孔隙特征与演化机理
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作者 赵飞 胡鑫 +2 位作者 韩璐 关继超 李国勇 《山西煤炭》 2025年第1期115-120,共6页
烧变岩的孔隙特征对注充填浆液的扩散距离与浆液水与水泥比例较大影响,通过吸水率测定、低场核磁共振技术等方法对烧变岩物理性质与孔隙结构进行了研究。结果表明,砂岩吸水率从1.4432%~7.2695%,泥岩吸水率为9.2290%~10.8180%;测试样品... 烧变岩的孔隙特征对注充填浆液的扩散距离与浆液水与水泥比例较大影响,通过吸水率测定、低场核磁共振技术等方法对烧变岩物理性质与孔隙结构进行了研究。结果表明,砂岩吸水率从1.4432%~7.2695%,泥岩吸水率为9.2290%~10.8180%;测试样品的T2图谱的波形基本不变,前峰降低后峰升高,整体向右移动;干湿循环的影响导致烧变岩的孔隙结构发生变化,虽然波形高低起伏,但峰型保持基本稳定,在前峰降低的同时,后峰上升。在循环过程中,微孔逐步演变为中孔,中孔又逐渐转化为大孔,导致微孔的比例逐步减少,而大孔的比例则持续上升,泥岩W-6、W-7的初始大孔比例为29%、38%;分别增加到48%与53%,变化最大;泥岩经过烧变后物性特征发生了显著变化,有利于介质流动与注浆充填。研究表明岩性与距离火焰远近是控制孔隙变化的主要因素。 展开更多
关键词 烧变岩 干湿循环 孔隙结构 孔隙类型
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某工程剪力墙混凝土点状爆裂原因的进一步分析
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作者 张鹏 杨超 《混凝土世界》 2025年第2期12-13,共2页
本文依据《混凝土世界》2024年11期刊登的《某工程剪力墙混凝土点状爆裂问题研究分析》与2024年12期刊登的《混凝土结构表面点状爆裂的原因分析》中关于混凝土点状爆裂的原因进行进一步讨论,通过再次调研、文献与工程实例分析,得出了混... 本文依据《混凝土世界》2024年11期刊登的《某工程剪力墙混凝土点状爆裂问题研究分析》与2024年12期刊登的《混凝土结构表面点状爆裂的原因分析》中关于混凝土点状爆裂的原因进行进一步讨论,通过再次调研、文献与工程实例分析,得出了混凝土产生点状爆裂的原因是骨料中混入了少量过火石灰缓慢吸水膨胀,从而产生由内向外的推力将混凝土拉裂。 展开更多
关键词 混凝土结构 点状爆裂 过火石灰
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Burnt Rubber
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作者 LIU XINLIAN 《Beijing Review》 2011年第49期32-33,共2页
Driving away Chinese tires has not benefited the U.S. tire industry, but has harmed their trade ties Two years after imposing punitive tariffs on Chinese-manufactured passenger vehicle and truck tires, the United Stat... Driving away Chinese tires has not benefited the U.S. tire industry, but has harmed their trade ties Two years after imposing punitive tariffs on Chinese-manufactured passenger vehicle and truck tires, the United States may launch a new round against truck and bus tires imported from China, reported 21st Century Business Herald based in Guangzhou, capital of Guangdong Province. 展开更多
关键词 WTO burnt Rubber
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基于数值模拟的神延西湾露天煤矿边坡稳定性分析
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作者 赵志荣 张飞云 《陕西煤炭》 2025年第1期92-98,共7页
西湾露天煤矿是国家能源集团的大型露天煤矿,煤炭产量高,产品质量优,在历年的能源保供任务中承担重要角色,西湾露天煤矿在开采过程中形成工作帮、边帮、排土场等边坡,较原始状态的边坡,稳定性存在不确定的因素。西湾露天煤矿地下水储量... 西湾露天煤矿是国家能源集团的大型露天煤矿,煤炭产量高,产品质量优,在历年的能源保供任务中承担重要角色,西湾露天煤矿在开采过程中形成工作帮、边帮、排土场等边坡,较原始状态的边坡,稳定性存在不确定的因素。西湾露天煤矿地下水储量丰富,尤其是东端帮火烧岩边界,地下水对岩土的分界面及地层的强度影响较大,边坡长期受涌水影响,岩层裂隙发育,孔隙变大,易造成边坡失衡;地表主要成分为砂土,局部遇水流沙,保安平盘留设困难,易发生片帮、坍塌、滑坡事故。本文通过对各个地层的岩性、构造、层理和地下含水体进行综合分析,使用极限平衡法、有限元分析法验算西湾露天煤矿边坡稳定系数,确定露天边坡的边坡角、爆破方式、平盘高度、平盘宽度等重要边坡稳定参数,保证边坡的稳定性,提高采剥效率,对露天煤矿的安全生产具有重要意义。 展开更多
关键词 露天煤矿 边坡稳定 数值模拟 烧变岩 边坡监测
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榆神矿区河兴梁井田2^(-2)煤烧变岩特征及对煤层开采的影响
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作者 李瑾 李明培 冯喜珍 《中国煤炭地质》 2025年第1期7-9,26,共4页
榆神矿区东部河兴梁井田2^(-2)煤层埋藏浅,沿煤层露头多发生自燃现象,形成烧变岩。为研究2^(-2)煤层烧变岩赋存规律及其对下伏煤层开采的影响,采用烧变岩露头剖面测量、地质钻探、抽水试验等手段,研究了2^(-2)煤层烧变岩的赋存规律、水... 榆神矿区东部河兴梁井田2^(-2)煤层埋藏浅,沿煤层露头多发生自燃现象,形成烧变岩。为研究2^(-2)煤层烧变岩赋存规律及其对下伏煤层开采的影响,采用烧变岩露头剖面测量、地质钻探、抽水试验等手段,研究了2^(-2)煤层烧变岩的赋存规律、水文地质特征,以及烧变岩水对下伏煤层开采的影响。结果表明:榆神矿区东部河兴梁井田2^(-2)煤层煤烧变岩呈条带状状分布,自下而上形成熔融岩带、烧结岩带和上部烘烤岩带。烧变岩孔洞、裂隙极其发育,厚度2.95~50.31m,烧变岩含水层以强富水性为主。3^(-1)煤层开采后导水裂缝带发育高度基本导通至烧变岩含水层,可能会导致矿井突水、溃沙灾害,对矿井安全生产有较大隐患。提出在烧变岩分布区采用完全充填开采方式开发3^(-1)煤层,实现安全开采的目的。 展开更多
关键词 保水采煤 烧变岩 水文地质特征 导水裂缝带 开采影响 河兴梁井田
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气相色谱-质谱法测定加热卷烟气溶胶中14种焦甜香成分 被引量:1
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作者 王昊 刘绍锋 +6 位作者 王冰 操吉学 秦亚琼 余晶晶 崔华鹏 杨俊鹏 蔡君兰 《化学分析计量》 CAS 2024年第5期42-47,共6页
建立气相色谱-质谱法测定加热卷烟气溶胶中14种焦甜香成分释放量。采用直线型吸烟机,在HCI(加拿大深度)抽吸模式下对加热卷烟进行抽吸,采用剑桥滤片对加热卷烟气溶胶进行捕集,用二氯甲烷溶液萃取剑桥滤片,萃取液经过滤后用气相色谱-质... 建立气相色谱-质谱法测定加热卷烟气溶胶中14种焦甜香成分释放量。采用直线型吸烟机,在HCI(加拿大深度)抽吸模式下对加热卷烟进行抽吸,采用剑桥滤片对加热卷烟气溶胶进行捕集,用二氯甲烷溶液萃取剑桥滤片,萃取液经过滤后用气相色谱-质谱法测定,以选择离子监测(SIM)模式采集质谱数据,以D8-苯乙酮作为内标定量分析。14种焦甜香化合物的质量浓度在0.1~80μg/mL范围内线性关系良好,相关系数均不小于0.998,方法检出限为0.004~0.028μg/mL,定量限为0.012~0.093μg/mL。空白样品加标回收率为85.0%~110.0%,测定结果的相对标准偏差为5.84%~9.48%(n=5)。该方法简单快速、测定结果准确可靠,适用于加热卷烟气溶胶中14种焦甜香成分的定量测定。 展开更多
关键词 气相色谱-质谱法 加热卷烟 烟气 焦甜香成分
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陕西省煤矿典型水灾隐患特征及治理技术 被引量:5
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作者 董书宁 樊敏 +5 位作者 郭小铭 刘英锋 郭康 姬中奎 李超峰 薛小渊 《煤炭学报》 EI CAS CSCD 北大核心 2024年第2期902-916,共15页
陕西省煤炭资源丰富,2022年煤炭产量达7.46亿t,是我国主要产煤省份之一。由于全省煤矿区地质及水文地质条件差异明显,煤矿水灾类型多样,随着近年煤炭开采强度的增大,水灾事故时有发生,防治水形势较为严峻。以煤炭赋存条件为基础,系统总... 陕西省煤炭资源丰富,2022年煤炭产量达7.46亿t,是我国主要产煤省份之一。由于全省煤矿区地质及水文地质条件差异明显,煤矿水灾类型多样,随着近年煤炭开采强度的增大,水灾事故时有发生,防治水形势较为严峻。以煤炭赋存条件为基础,系统总结区域水文地质结构特征,界定典型水灾类型及各类水灾影响区域分布,论述典型水灾的形成机理及特征,并提出了相应的防控技术。研究表明:(1)陕西省主要煤炭产区分为陕北、黄陇、渭北三大区,陕北侏罗纪煤田主要有顶板松散沙层水灾隐患、厚层砂岩水灾隐患、溃水溃沙灾害,局部区域分布有烧变岩对煤矿造成水灾隐患;黄陇煤田主要受顶板巨厚砂岩水灾隐患、离层溃水隐患、泥砂溃涌灾害隐患威胁;陕北石炭—二叠纪煤田和渭北煤田,主要受到煤层底板奥陶系灰岩水灾隐患威胁。(2)陕北侏罗系煤田顶板水灾隐患主要为顶板含水层受开采导水裂隙带扰动形成,导水裂隙波及砂岩含水层或松散沙层可形成持续大流量涌水,部分区域充水强度较大,在短时间水量较大超过排水系统能力时造成顶板水灾,在薄基岩区域垮落带直接导通松散沙层时可转变为溃水溃沙灾害,导水裂隙带影响到烧变岩富水区域时可形成瞬时水量大且持续的烧变岩水灾;黄陇煤田顶板巨厚砂岩含水层受采动导水裂隙带波及形成高强度持续涌水并可能形成顶板水灾,当含水层下部隔水层厚度较大时,可能形成离层溃水灾害,当近煤层顶板岩层松软遇水易崩解时可转变为泥砂溃涌灾害;陕北石炭—二叠纪煤田和渭北煤田,煤层开采底板扰动破坏带或断层等构造导通奥陶系灰岩含水层时,会引发极为严重的底板突水灾害,该类灾害具突发性强、瞬时水量大的特征。(3)各区域的顶板水灾隐患治理技术主要包括钻孔疏泄、注浆治理、开采参数控制等,底板水灾隐患治理技术主要包括区域注浆加固及封堵等;烧变岩水灾隐患主要采取帷幕注浆与钻孔探放有机结合的防治技术。 展开更多
关键词 陕西省煤矿 溃水溃沙 烧变岩水灾 离层溃水 泥砂溃涌 底板奥灰水灾
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某大型集装箱船中间轴承故障分析与处理 被引量:1
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作者 易小冬 徐逸然 蔡鹤 《船舶工程》 CSCD 北大核心 2024年第5期84-88,共5页
某大型集装箱船为系列船,其中有2条船发生了同样的中间轴承轴瓦烧毁故障,因此开展该型船故障原因分析尤为重要。通过对推进系统的设计、安装调试和运营记录等多方面进行问题排查,并进行失效分析,还原故障的发生过程,分析故障的发生机理... 某大型集装箱船为系列船,其中有2条船发生了同样的中间轴承轴瓦烧毁故障,因此开展该型船故障原因分析尤为重要。通过对推进系统的设计、安装调试和运营记录等多方面进行问题排查,并进行失效分析,还原故障的发生过程,分析故障的发生机理,从而提出了改进措施。通过故障案例分析,可为推进系统类似故障分析及处理提供经验和参考。 展开更多
关键词 大型集装箱船 中间轴承 轴瓦烧毁 故障分析
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