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大数据背景下的企业财务管理模式创新研究 被引量:3
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作者 石油 《经济管理文摘》 2020年第3期108-109,共2页
现阶段,在全球范围中的信息技术都得到了十分迅猛地发展,这就使得大数据技术获得了更为普遍地使用,且其与各个领域间密切相连。处于这一前提下,给企业所进行的财务管理给予了更多的要求,各个企业仅有适应于大数据时代,才可以让财务管理... 现阶段,在全球范围中的信息技术都得到了十分迅猛地发展,这就使得大数据技术获得了更为普遍地使用,且其与各个领域间密切相连。处于这一前提下,给企业所进行的财务管理给予了更多的要求,各个企业仅有适应于大数据时代,才可以让财务管理最大限度地得到升级、创新。为此,本次先阐述了企业财务管理所具有的各类作用,并鉴于大数据背景下给出了企业进行创新性财务管理的各项对策。 展开更多
关键词 大数据时代 财务管理 创新升级 企业
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低钠血症及血钠波动对动脉瘤性蛛网膜下腔出血患者预后的影响研究 被引量:1
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作者 石油 朱继 《医学信息》 2018年第3期73-77,共5页
目的观察动脉瘤性蛛网膜下腔出血(aSAH)中低钠血症与血钠波动的特点,分析低钠血症与钠波动的关系及对预后的影响。方法回顾性分析重庆医科大学附属第一医院2017年1月~8月收治的189例aSAH病例,根据血钠波动最大值,分为<6 mmol/L,6~12 ... 目的观察动脉瘤性蛛网膜下腔出血(aSAH)中低钠血症与血钠波动的特点,分析低钠血症与钠波动的关系及对预后的影响。方法回顾性分析重庆医科大学附属第一医院2017年1月~8月收治的189例aSAH病例,根据血钠波动最大值,分为<6 mmol/L,6~12 mmol/L,>12 mmol/L三组,以Rankin修订量表评分(mRS)评估患者预后,使用Logistic回归分析血钠波动与患者预后的联系。结果 mRS≥4组的患者发病后入院时间间隔短于mRS≤1组,mRS≥4组的患者鞍上池出血区域CT值均值最高,差异有统计学意义(P<0.05)。患有糖尿病和高血压的患者预后差,Fisher分级为Ⅲ~Ⅳ级的患者较Ⅰ~Ⅱ级的预后差,差异有统计学意义(P<0.01)。发生位置在后循环的患者比颈内动脉段预后较差,差异有统计学意义(P<0.05)。低钠血症与不良的神经功能预后相比,差异无统计学意义(P>0.05)。每日钠波动6~12 mmol/L组中,mRS≤1者26例(31.71%),2≤mRS≤3者25例(30.49%),mRS≥4者31例(37.80%);>12mmol/L组中mRS≤1者1例(6.67%),2≤mRS≤3者2例(13.33%),mRS≥4者12例(80.00%)。病程中血钠波动6~12 mmol/L及>12 mmol/L组,较<6 mmol/L组患者mRS评分更高,预后更差,差异具有统计学意义(P<0.05)。结论 aSAH患者中,血钠的波动,而非低血钠本身,与不良神经功能预后有统计学关联,这与现行的理念存在冲突,有待更进一步的临床探索。 展开更多
关键词 动脉瘤性蛛网膜下腔出血 血钠波动 低钠血症 Rankin修订量表评分
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油田维护费会计问题研究
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作者 <石油 天然气会计问题研究>课题组 《会计研究》 CSSCI 北大核心 2001年第9期34-37,共4页
油田维护费的核算是石油天然气企业会计核算的三大难题之一。我国现行的油田维护费制度对油气田建设及发展起到了积极的作用 ,但也存在许多问题与缺陷。本文主要在调查研究的基础上 ,通过分析我国油田维护费制度存在的问题 ,借鉴美国等... 油田维护费的核算是石油天然气企业会计核算的三大难题之一。我国现行的油田维护费制度对油气田建设及发展起到了积极的作用 ,但也存在许多问题与缺陷。本文主要在调查研究的基础上 ,通过分析我国油田维护费制度存在的问题 ,借鉴美国等国家的有关会计准则 ,对油田维护活动及油田维护费的若干热点问题进行探讨 ,对如何改革我国油田维护费会计核算体系提出设想与建议 ,以期有助于我国石油天然气会计准则的建立与完善。 展开更多
关键词 油田维护 油田维护费 后续勘探 后续开发 资本化 费用化 石油天然气企业 会计核算 中国
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泌阳凹陷碱性成岩作用及其对储层的影响 被引量:95
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作者 邱隆伟 姜在兴 +6 位作者 操应长 石油大学 华东 资源系 东营 邱荣华 陈文学 《中国科学(D辑)》 CSCD 北大核心 2001年第9期752-759,共8页
碱性成岩作用是指总体在碱性成岩环境下储层所经历的成岩作用历程. 由于碱性地层水的作用, 使得石英的显著溶蚀和长石的大规模加大成为最具特色的成岩现象, 碳酸盐矿物在演化上也出现晚期碳酸盐胶结物分布较少等特点. 随着成岩作用程度... 碱性成岩作用是指总体在碱性成岩环境下储层所经历的成岩作用历程. 由于碱性地层水的作用, 使得石英的显著溶蚀和长石的大规模加大成为最具特色的成岩现象, 碳酸盐矿物在演化上也出现晚期碳酸盐胶结物分布较少等特点. 随着成岩作用程度的加深和地层水碱性程度的下降, 石英的加大现象也变得很普遍. 在成岩作用过程中由于地层水性质的变化而导致储层孔隙在纵向分布上比经典的酸性水成因次生孔隙的分布更为复杂, 也使得早成岩B期成为重要的次生孔隙发育期. 展开更多
关键词 碱性成岩作用 石英溶解 次生孔隙 泌阳凹陷 碱性地层水 酸性水
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Advances in the production technology of hydrogen peroxide 被引量:23
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作者 Guohua Gao Yanan Tian +3 位作者 Xiaoxiao Gong Zhiyong Pan Keyong Yang Baoning Zong 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第7期1039-1047,共9页
This article mainly summarizes various aspects of hydrogen peroxide(H2O2)production through the anthraquinone route,including hydrogenation catalysts,working solution,regeneration technique,hydrogenation reactors,and ... This article mainly summarizes various aspects of hydrogen peroxide(H2O2)production through the anthraquinone route,including hydrogenation catalysts,working solution,regeneration technique,hydrogenation reactors,and environmental protection.The advances and breakthrough of SINOPEC in the production of H2O2 through the anthraquinone route is presented in this review,highlighting recent innovative technology on these aspects developed independently.The technical prospect and scientific challenges associated with the direct synthesis method from hydrogen and oxygen are also briefly discussed. 展开更多
关键词 Hydrogen peroxide Anthraquinone auto-oxidation Hydrogenation of anthraquinone Hydrogenation catalyst Production Technology
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深盆气资源量—储量评价方法 被引量:20
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作者 张金川 金之钧 +2 位作者 石油大学 北京 郑浚茂 《天然气工业》 EI CAS CSCD 北大核心 2001年第4期32-35,共4页
深盆气藏是致密储层中与源岩相连的有根状气水倒置关系的气藏 ,是一类在成藏机理和分布规律方面都比较特殊的油气藏类型 ,常发育在盆地的构造低部位 ,在碎屑岩沉积盆地中具有广阔的勘探和发现前景。目前对深盆气资源量—储量评价方法的... 深盆气藏是致密储层中与源岩相连的有根状气水倒置关系的气藏 ,是一类在成藏机理和分布规律方面都比较特殊的油气藏类型 ,常发育在盆地的构造低部位 ,在碎屑岩沉积盆地中具有广阔的勘探和发现前景。目前对深盆气资源量—储量评价方法的系统研究基本上仍是一个空白。根据深盆气藏的基本特征 ,结合油气资源评价方法论中的基本原则 ,较为扼要系统地提出了 10种深盆气资源量—储量预测方法 :特尔菲估计法、相似盆地地质条件类比法、盆地剩余资源量分析法、天然气聚散平衡计算法、地层流体异常压力恢复法、深盆气成藏条件分析预测法、盆地数值模拟法、深盆气藏甜点规模序列法、有效储层体积 (容积 ) 展开更多
关键词 深盆地 天然气 资源评价 资源量计算 储量计算
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Nuclear magnetic resonance T_2 spectrum:multifractal characteristics and pore structure evaluation 被引量:20
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作者 Yan Jian-Ping He Xu +4 位作者 Geng Bin Hu Qin-Hong Feng Chun-Zhen Kou Xiao-Pan Li Xing-Wen 《Applied Geophysics》 SCIE CSCD 2017年第2期205-215,322,共12页
Pore structure characteristics are important to oil and gas exploration in complex low-permeability reservoirs. Using multifractal theory and nuclear magnetic resonance (NMR), we studied the pore structure of low-pe... Pore structure characteristics are important to oil and gas exploration in complex low-permeability reservoirs. Using multifractal theory and nuclear magnetic resonance (NMR), we studied the pore structure of low-permeability sandstone rocks from the 4th Member (Es4) of the Shahejie Formation in the south slope of the Dongying Sag. We used the existing pore structure data from petrophysics, core slices, and mercury injection tests to classify the pore structure into three categories and five subcategories. Then, the T2 spectra of samples with different pore structures were interpolated, and the one- and three-dimensional fractal dimensions and the multifractal spectrum were obtained. Parameters a (intensity of singularity) andf(a) (density of distribution) were extracted from the multifractal spectra. The differences in the three fractal dimensions suggest that the pore structure types correlate with a andf(a). The results calculated based on the multifractal spectrum is consistent with that of the core slices and mercury injection. Finally, the proposed method was applied to an actual logging profile to evaluate the pore structure of low-permeability sandstone reservoirs. 展开更多
关键词 NMR T2 spectrum MULTIFRACTAL INTERPOLATION pore structure PERMEABILITY SANDSTONE
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干摩擦条件下天然橡胶/钢的磨损机理研究 被引量:14
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作者 何仁洋 张嗣伟 +1 位作者 王德国 石油大学 《摩擦学学报》 EI CAS CSCD 北大核心 2001年第4期260-265,共6页
采用 FAL EX试验机考察了 2 0 #钢 /天然橡胶在干摩擦条件下的磨损机理 .用扫描电子显微镜分析了 2 0 #钢和橡胶磨损表面形貌 ,用 X射线光电子能谱仪分析了金属和橡胶磨损表面元素的含量及化学状态 ,用镜面全反射傅立叶红外光谱仪分析... 采用 FAL EX试验机考察了 2 0 #钢 /天然橡胶在干摩擦条件下的磨损机理 .用扫描电子显微镜分析了 2 0 #钢和橡胶磨损表面形貌 ,用 X射线光电子能谱仪分析了金属和橡胶磨损表面元素的含量及化学状态 ,用镜面全反射傅立叶红外光谱仪分析了橡胶磨损表面官能团的变化 .结果表明 ,2 0 #钢 /天然橡胶摩擦副发生了粘着磨损 ,其磨损机制为 :金属及金属氧化物与天然橡胶大分子自由基在摩擦表面发生反应 ;在亚表层以金属与大分子自由基的反应为主 ,主要产物为含有 Fe- C的金属 -聚合物 ;金属本身发生氧化 ,主要产物为 Fe2 O3、Fe O和 Fe3O4,而在亚表层的主要产物以 Fe O为主 .表面膜可能通过化学键。 展开更多
关键词 20^#钢 天然橡胶 磨损机制 力化学效应 干摩擦
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Structure, synthesis, and catalytic properties of nanosize cerium-zirconium-based solid solutions in environmental catalysis 被引量:19
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作者 Jixing Liu Zhen Zhao +1 位作者 Chunming Xu Jian Liu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第10期1438-1487,共50页
Nanosize cerium-zirconium solid solution(CZO)with a special fluorite structure has received an increasing research interest due to their remarkable advantages such as excellent oxygen storage capacity and great flexib... Nanosize cerium-zirconium solid solution(CZO)with a special fluorite structure has received an increasing research interest due to their remarkable advantages such as excellent oxygen storage capacity and great flexibility in their composition and structure.By partial metal(including rare earth,transition,alkaline earth or other metal)doping into CZO,the physicochemical properties of these catalytic materials can be controllable adjusted for the study of specific reactions.To date,nanosize CZO has been prepared by co-precipitation,sol-gel,surfactant-assisted approach,solution combustion,micro-emulsion,high energy mechanical milling,etc.The advent of these methodologies has prompted researchers to construct well-defined networks with customized micromorphology and functionalities.In this review,we describe not only the basic structure and synthetic strategies of CZO,but also their relevant applications in environmental catalysis,such as the purification for CO,nitrogen oxides(NOx),volatile organic compounds(VOC),soot,hydrocarbon(HC),CO2 and solid particulate matters(PM),and some reaction mechanisms are also summarized. 展开更多
关键词 Cerium-zirconium solid solution SYNTHESIS Method STRUCTURE Environmental catalysis
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低速非达西渗流的流量动态规律研究 被引量:6
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作者 程时清 郭康良 +3 位作者 周吉培 栗波 鹏会新 辽河石油勘探局 《江汉石油学院学报》 CSCD 北大核心 1997年第1期56-60,共5页
建立了考虑表皮(超肤)效应作用的低速非达西渗流定井底流压生产的数学模型,求出了流量和累积流量的拉普拉斯空间解;采用Stehfest数值反演算法,绘制了流量和累积流量变化曲线;讨论了启动压力梯度和表皮效应的影响及非达西... 建立了考虑表皮(超肤)效应作用的低速非达西渗流定井底流压生产的数学模型,求出了流量和累积流量的拉普拉斯空间解;采用Stehfest数值反演算法,绘制了流量和累积流量变化曲线;讨论了启动压力梯度和表皮效应的影响及非达西渗流与达西渗流流量动态的差别。获得的结果有助于分析油井早期生产数据,确定地层参数和预测油井动态。 展开更多
关键词 渗流 非达西流 流量 地夫效应 低渗透油气藏
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Novel SiO2 nanoparticle-decorated BiOCl nanosheets exhibiting high photocatalytic performances for the removal of organic pollutants 被引量:16
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作者 Changlin Yu Hongbo He +2 位作者 Xingqiang Liu Julan Zeng Zhen Liu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第8期1212-1221,共10页
Novel SiO2/BiOCl composites were fabricated by decorating BiOCl nanosheets with SiO2 nanoparticles via a simple hydrothermal process. The as-prepared pure BiOCl and SiO2/BiOCl composites were intensively characterized... Novel SiO2/BiOCl composites were fabricated by decorating BiOCl nanosheets with SiO2 nanoparticles via a simple hydrothermal process. The as-prepared pure BiOCl and SiO2/BiOCl composites were intensively characterized by various techniques such as XRD, FT-IR, SEM/TEM, BET, UV-vis, DRS, XPS, and photocurrent measurements. The SiO2/BiOCl composite nanosheets displayed high photocatalytic activity and excellent stability in the degradation of organic pollutants such as phenol, bisphenol A (BPA), and rhodamine B (RhB). With respect to those over bare BiOCl, the degradation rates of RhB, BPA, and phenol over 1.88% SiO2/BiOCl increased 16.5%, 29.0%, and 38.7%, respectively. Radical capturing results suggested that h^+ is the major reactive species and that hydroxyl (·OH) and superoxide (·O2^-) radicals could also be involved in the degradation of organic pollutants. The enhanced photocatalytic performances of SiO2/BiOCl composites can be mainly attributed to the improved texture and the formation of intimate SiO2/BiOCl interfaces, which largely promoted the adsorption of organic pollutants, enhanced the light harvesting, and accelerated the separation of e^– and h^+. 展开更多
关键词 SiO2/BiOCl NANOSHEETS Organic pollutant PHOTOCATALYSIS Interface
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金属卟啉催化加氢脱金属的初步研究 被引量:10
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作者 徐海 于道永 +2 位作者 王宗贤 阙国和 石油大学 《石油学报(石油加工)》 EI CAS CSCD 北大核心 2001年第4期18-23,共6页
在装有工业加氢脱金属催化剂 ( ICR)的高压连续微型反应装置中 ,对镍 -2 ,3,7,8,1 2 ,1 3,1 7,1 8-八乙基卟啉 ( Ni-OEP)和氧钒 -2 ,3,7,8,1 2 ,1 3,1 7,1 8-八乙基卟啉 ( VO-OEP)的加氢反应进行了初步探索。金属卟啉的加氢脱金属历程... 在装有工业加氢脱金属催化剂 ( ICR)的高压连续微型反应装置中 ,对镍 -2 ,3,7,8,1 2 ,1 3,1 7,1 8-八乙基卟啉 ( Ni-OEP)和氧钒 -2 ,3,7,8,1 2 ,1 3,1 7,1 8-八乙基卟啉 ( VO-OEP)的加氢反应进行了初步探索。金属卟啉的加氢脱金属历程分为两步。第 1步 ,金属卟啉的一个外环双键加氢生成金属卟酚 (二氢金属卟啉 ) ;第 2步 ,金属卟酚分解 ,金属沉积在催化剂上。金属卟酚的分解过程比较复杂 ,它可被进一步加氢成四氢金属卟啉和八氢金属卟啉。在相同反应条件下 ,VO-OEP比 Ni-OEP容易催化加氢脱金属。吡啶和二硫化碳的存在不改变金属卟啉加氢脱金属反应过程 ,但吡啶对金属卟啉的催化加氢脱金属反应有抑制作用 。 展开更多
关键词 镍卟啉 钒卟啉 催化加氢 脱金属 反应过程 炼油
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Multi-resolution graph-based clustering analysis for lithofacies identifi cation from well log data: Case study of intraplatform bank gas fi elds, Amu Darya Basin 被引量:12
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作者 Tian Yu Xu Hong +4 位作者 Zhang Xing-Yang Wang Hong-Jun Guo Tong-Cui Zhang Liang-Jie Gong Xing-Lin 《Applied Geophysics》 SCIE CSCD 2016年第4期598-607,736,共11页
In this study, we used the multi-resolution graph-based clustering (MRGC) method for determining the electrofacies (EF) and lithofacies (LF) from well log data obtained from the intraplatform bank gas fields loc... In this study, we used the multi-resolution graph-based clustering (MRGC) method for determining the electrofacies (EF) and lithofacies (LF) from well log data obtained from the intraplatform bank gas fields located in the Amu Darya Basin. The MRGC could automatically determine the optimal number of clusters without prior knowledge about the structure or cluster numbers of the analyzed data set and allowed the users to control the level of detail actually needed to define the EF. Based on the LF identification and successful EF calibration using core data, an MRGC EF partition model including five clusters and a quantitative LF interpretation chart were constructed. The EF clusters 1 to 5 were interpreted as lagoon, anhydrite flat, interbank, low-energy bank, and high-energy bank, and the coincidence rate in the cored interval could reach 85%. We concluded that the MRGC could be accurately applied to predict the LF in non-cored but logged wells. Therefore, continuous EF clusters were partitioned and corresponding LF were characteristics &different LF were analyzed interpreted, and the distribution and petrophysical in the framework of sequence stratigraphy. 展开更多
关键词 Multi-resolution graph-based clustering method electrofacies lithofacies intraplatform bank gas fields Amu Darya Basin
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Continuous TDEM for monitoring shale hydraulic fracturing 被引量:13
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作者 Yan Liang-Jun Chen Xiao-Xiong +4 位作者 Tang Hao Xie Xing-Bing Zhou Lei Hu Wen-Bao and Wang Zhong-Xin 《Applied Geophysics》 SCIE CSCD 2018年第1期26-34,147,148,共11页
Monitoring and delineating the spatial distribution of shale fracturing is fundamentally important to shale gas production. Standard monitoring methods, such as time-lapse seismic, cross-well seismic and micro-seismic... Monitoring and delineating the spatial distribution of shale fracturing is fundamentally important to shale gas production. Standard monitoring methods, such as time-lapse seismic, cross-well seismic and micro-seismic methods, are expensive, time- consuming, and do not show the changes in the formation with time. The resistivities of hydraulic fracturing fluid and reservoir rocks were measured. The results suggest that the injection fluid and consequently the injected reservoir are characterized by very low resistivity and high chargeability. This allows using of the controlled-source electromagnetic method (CSEM) to monitor shale gas hydraulic fracturing. Based on the geoelectrical model which was proposed according to the well-log and seismic data in the test area the change rule of the reacted electrical field was studied to account for the change of shale resistivity, and then the normalized residual resistivity method for time lapse processing was given. The time-domain electromagnetic method (TDEM) was used to continuously monitor the shale gas fracturing at the Fulin shale gas field in southern China. A high-power transmitter and multi-channel transient electromagnetic receiver array were adopted. 9 h time series of Ex component of 224 sites which were laid out on the surface and over three fracturing stages of a horizontal well at 2800 m depth was recorded. After data processing and calculation of the normalized resistivity residuals, the changes in the Ex signal were determined and a dynamic 3D image of the change in resistivity was constructed. This allows modeling the spatial distribution of the fracturing fluid. The model results suggest that TDEM is promising for monitoring hydraulic fracturing of shale. 展开更多
关键词 Shale fracturing RESISTIVITY time lapse 3D imaging continuous monitoring
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Recent advances in VOCs and CO removal via photothermal synergistic catalysis 被引量:13
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作者 Longfu Wei Changlin Yu +2 位作者 Kai Yang Qizhe Fan Hongbing Ji 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第7期1078-1095,共18页
Currently,air pollution is being exacerbated by rapid social,economic,and industrial development.Major air pollutants include volatile organic compounds(VOCs)and CO.Photocatalytic and thermocatalytic technology can be... Currently,air pollution is being exacerbated by rapid social,economic,and industrial development.Major air pollutants include volatile organic compounds(VOCs)and CO.Photocatalytic and thermocatalytic technology can be used to convert VOCs and CO into harmless gases effectively.Recently,photothermal synergistic catalysis has aroused much attention because of its higher performance than those of individual photocatalytic and thermocatalytic processes.There have been many reviews on separate photocatalysts and thermocatalysts for the treatment of VOCs and CO,but few reviews have focused on photothermal synergistic catalysis.In this minireview,we concentrate on recent progress into photothermal synergistic catalysis for the efficient removal of VOCs and CO.The treatment of typical VOCs(such as benzene,toluene,ethanol,formaldehyde,acetone,propylene,and propane)and CO are summarized and analyzed.Furthermore,we discuss the use of conventional reactor technology,such as fixed‐bed quartz reactors,for VOCs and CO removal.We also discuss the mechanism of the photothermal synergistic catalytic removal of VOCs and CO.Finally,we present perspectives for the photothermal synergistic catalytic removal of VOCs and CO. 展开更多
关键词 Volatile organic compounds Carbon monoxide PHOTOCATALYSIS Thermocatalysis Photothermal synergistic catalysis
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Correlation between H-ZSM-5 crystal size and catalytic performance in the methanol-to-aromatics reaction 被引量:14
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作者 Lingzhi Yang Zhiyuan Liu +3 位作者 Zhi Liu Wenyong Peng Yunqi Liu Chenguang Liu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2017年第4期683-690,共8页
The porosity of H‐ZSM‐5zeolite is known to facilitate the diffusion of molecules in the methanol‐to‐aromatics(MTA)reaction.The activity and selectivity of the H‐ZSM‐5catalyst in the MTAreaction has been studied ... The porosity of H‐ZSM‐5zeolite is known to facilitate the diffusion of molecules in the methanol‐to‐aromatics(MTA)reaction.The activity and selectivity of the H‐ZSM‐5catalyst in the MTAreaction has been studied as a function of crystal size.ZSM‐5zeolites with different crystal sizeswere successfully synthesized by conventional hydrothermal methods.Tailoring ZSM‐5particle sizewas easily controlled by changes to the sol‐gel composition,and in particular,the deionized waterto tetrapropylammonium hydroxide ratio,and crystallization time.The structure of the H‐ZSM‐5zeolites were characterized by X‐ray diffraction and the morphology of the zeolite particles wasdetermined by scanning electron microscopy.N2adsorption‐desorption measurements establishedchanges to the textural properties,and compositional properties were characterized by X‐ray fluorescencespectroscopy.Acidity measurements of the catalysts were measured by pyridine‐adsorbedFourier transform infrared spectroscopy and the temperature‐programmed desorption of ammonia.After subjecting the catalysts to the MTA reaction,the total amount of coke formed on the spentdeactivated catalysts was determined by thermal gravimetric analysis.The results show that theSiO2/Al2O3molar ratios and acidic properties of the H‐ZSM‐5samples are similar,however,thenano‐sized hierarchical ZSM‐5zeolite with an additional level of auxiliary pores possesses a higher 展开更多
关键词 METHANOL AROMATICS Nano‐sized H‐ZSM‐5 Hierarchical structure Crystal size
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Application of four-component dipole shear reflection imaging to interpret the geological structure around a deviated well 被引量:11
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作者 Lee Sheng-Qing Chen Ming +2 位作者 Gu Xi-Hao Su Yuan-Da Tang Xiao-Ming 《Applied Geophysics》 SCIE CSCD 2019年第3期291-301,395,共12页
Acoustic reflection imaging in deep water wells is a new application scope for offshore hydrocarbon exploration.Two-dimensional(2 D)geological structure images can be obtained away from a one-dimensional(1 D)borehole ... Acoustic reflection imaging in deep water wells is a new application scope for offshore hydrocarbon exploration.Two-dimensional(2 D)geological structure images can be obtained away from a one-dimensional(1 D)borehole using single-well acoustic reflection imaging.Based on the directivity of dipole source and four-component dipole data,one can achieve the azimuth detection and the three-dimensional(3 D)structural information around the wellbore can be obtained.We first perform matrix rotation on the field fourcomponent data.Then,a series of processing steps are applied to the rotated dipole data to obtain the reflector image.According to the above dipole shear-wave imaging principle,we used four-component cross-dipole logging data from a deviated well in the South China Sea to image geological structures within 50 m of a deviated well,which can delineate the structural configuration and determine its orientation.The configuration of near-borehole bedding boundaries and fault structures from shear-wave imaging results agrees with those from the Inline and Xline seismic profiles of the study area.In addition,the configuration and orientation of the fault structure images are consistent with regional stress maps and the results of the borehole stress anisotropy analysis.Furthermore,the dip azimuth of the bedding boundary images was determined using borehole wall resistivity data.Results of this study indicate that integrating borehole acoustic reflection with seismic imaging not only fills the gap between the two measurement scales but also accurately delineates geological structures in the borehole vicinity. 展开更多
关键词 four-component cross-dipole logging single-well shear-wave imaging seismicwell tie geological structure imaging fault imaging
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The roles and mechanism of cocatalysts in photocatalytic water splitting to produce hydrogen 被引量:12
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作者 Nan Xiao Songsong Li +3 位作者 Xuli Li Lei Ge Yangqin Gao Ning Li 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第4期642-671,共30页
Photocatalytic hydrogen(H2)evolution via water spilling over semiconductors has been considered to be one of the most promising strategies for sustainable energy supply in the future to provide non-pollution and renew... Photocatalytic hydrogen(H2)evolution via water spilling over semiconductors has been considered to be one of the most promising strategies for sustainable energy supply in the future to provide non-pollution and renewable energy.The key to efficient conversion of solar-chemical energy is the design of an efficient structure for high charge separation and transportation.Therefore,cocatalysts are necessary in boosting photocatalytic H2 evolution.To date,semiconductor photocatalysts have been modified by various cocatalysts due to the extended light harvest,enhanced charge carrier separation efficiency and improved stability.This review focuses on recent developments of cocatalysts in photocatalytic H2 evolution,the roles and mechanism of the cocatalysts are discussed in detail.The cocatalysts can be divided into the following categories:metal/alloy cocatalysts,metal phosphides cocatalysts,metal oxide/hydroxide cocatalysts,carbon-based cocatalysts,dual cocatalysts,Z-scheme cocatalysts and MOFs cocatalysts.The future research and forecast for photocatalytic hydrogen generation are also suggested. 展开更多
关键词 COCATALYSTS Photocatalytsts Hydrogen evolution Charge separation Water splitting
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大庆长垣水淹层测井评价技术的研究 被引量:6
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作者 安丰全 大庆石油学院 罗娜 《石油学报》 EI CAS CSCD 北大核心 1998年第3期68-72,共5页
在分析大庆油田常规水淹层测井评价技术、密闭及常规取心分析资料和混合流体电阻率变化规律的基础上,运用统计学方法建立了一套计算水淹层参数的数学模型,并认为大庆油田厚油层混合水电阻率是驱油效率和注入水电阻率的函数,可用一非... 在分析大庆油田常规水淹层测井评价技术、密闭及常规取心分析资料和混合流体电阻率变化规律的基础上,运用统计学方法建立了一套计算水淹层参数的数学模型,并认为大庆油田厚油层混合水电阻率是驱油效率和注入水电阻率的函数,可用一非线性S型函数来表示。利用DFPBFS最优化算法求解上述函数和广义阿尔奇公式组成的二元非线性方程组,可得出剩余油饱和度和混合水电阻率,进而评价油层的水淹程度。经处理大庆油田三口密闭取心井测井资料表明该方法效果良好。 展开更多
关键词 水淹层 剩余油饱和度 地层水电阻率 大庆 测井评价
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Preparation of N‐vacancy‐doped g‐C_3N_4 with outstanding photocatalytic H_2O_2 production ability by dielectric barrier discharge plasma treatment 被引量:10
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作者 Xuhe Li Jian Zhang +4 位作者 Feng Zhou Hongliang Zhang Jin Bai Yanjuan Wang Haiyan Wang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第6期1090-1098,共9页
Dielectric barrier discharge(DBD) plasma is considered to be a promising method to synthesize solid catalysts. In this work, DBD plasma was used to synthesize a nitrogen‐vacancy‐doped g‐C3N4 catalyst in situ for ... Dielectric barrier discharge(DBD) plasma is considered to be a promising method to synthesize solid catalysts. In this work, DBD plasma was used to synthesize a nitrogen‐vacancy‐doped g‐C3N4 catalyst in situ for the first time. X‐ray diffraction, N2 adsorption, ultraviolet–visible spectroscopy, scanning electron microscopy, transmission electron microscopy, X‐ray photoelectron spectrosco‐py, electrochemical impedance spectroscopy, electron paramagnetic resonance, O2 tempera‐ture‐programmed desorption, and photoluminescence were used to characterize the obtained cat‐alysts. The photocatalytic H2O2 production ability of the as‐prepared catalyst was investigated. The results show that plasma treatment influences the morphology, structure, and optical properties of the as‐prepared catalyst. Nitrogen vacancies are active centers, which can adsorb reactant oxygen molecules, trap photoelectrons, and promote the transfer of photoelectrons from the catalyst to the adsorbed oxygen molecules for the subsequent reduction reaction. This work provides a new strat‐egy for synthesizing g‐C3N4‐based catalysts. 展开更多
关键词 Dielectric BARRIER discharge plasma Graphitic carbonnitride H2O2 productionNitrogen VACANCIES PHOTOCATALYSIS
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