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Stress sensitivity of coal reservoir and its impact on coalbed methane production in the southern Qinshui Basin, north China

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Frontiers of Earth Science 2023年第1期17卷 4-17页

作者： Huimin JIA Yidong CAI Qiujia HU Cong ZHANG feng QIU Bin fan Chonghao MAO CBM Exploration and Development Branch PetroChina Huabei Oilfeld CompanyChangzhi 046000China School of Energy Resources China University of GeosciencesBeijing 100083China

Stress sensitivity has significant negative effects on the permeability and production of coalbed methane(CBM)*** effectively minimize these negative effects,the degree of stress sensitivity during the CBM production process should be carefully *** this work,the curvature of the stress-sensitivity curve was adopted to explore the degree of stress sensitivity,dividing the stress-sensitivity curve and the drainage process into five stress stages:sharp decrease,rapid decrease,low-speed decrease,slower decrease and harmless with four critical stress points—transition,sensitivity,relief and *** actual stages were determined by the initial permeability,stress-sensitivity coefficient and difference between the reservoir pressure and desorption *** four critical stress points did not completely exist in the stress-sensitivity *** an increase in the initial permeability of coal,the number of existing critical stresses increases,leading to different gas-water drainage strategies for CBM *** reservoirs with a certain stress-sensitivity coefficient,the permeability at the sensitive stress point was successively greater than that at the transition,relief and the harmless *** the stress-sensitivity coefficient is different,the stage is different at the beginning of drainage,and with an increase in the stress-sensitivity coefficient,the decrease rate of the permeability ***,the stress-sensitivity coefficient determines the ability to maintain stable CBM *** well-fractured CBM reservoirs,with a high stress-sensitivity coefficient,permeability damage mainly occurs when the reservoir pressure is less than the relief stress;therefore,the depressurization rate should be *** CBM reservoirs with fewer natural fractures,the reverse applies,and the depressurization rate can be much *** higher the difference between the reservoir and desorption pressures,the higher the effective stress and perme

关键词： coalbed methane stress sensitivity curvature stages division drainage

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超声乳化联合手法娩核手术治疗硬核白内障

实用防盲技术 2006年第4期1卷 12-13,22页

作者：姚念杰范峰赵运庭王晓红安徽省淮北市人民医院眼科 235000

目的探讨超声乳化联合手法娩核PMMA人工晶状体植入手术治疗硬核白内障的效果。方法对30例Ⅳ级以上核白内障施行超声乳化联合手法娩核PMMA人工晶状体植入术,观察术中、术后并发症,术后视力。结果超声乳化时间为0．1～0．5min。全部30例... 详细信息

目的探讨超声乳化联合手法娩核PMMA人工晶状体植入手术治疗硬核白内障的效果。方法对30例Ⅳ级以上核白内障施行超声乳化联合手法娩核PMMA人工晶状体植入术,观察术中、术后并发症,术后视力。结果超声乳化时间为0．1～0．5min。全部30例均顺利一期囊袋内人工晶状体植入。术后1天视力≥0．5者20眼占66．7％,术后一周视力≥0．5者25眼占83．3％。无严重并发症发生。结论超声乳化联合手法娩核技术可以减少超声能量,安全怏捷,组织损伤小,术后反应轻,视力恢复快等优点,是Ⅳ级以上核白内障较理想的手术方式。

关键词：超声乳化手法娩核硬核白内障

Modeling and Optimization of a Fractionation,Absorption,and Stabilization System in an Industrial Fluid Catalytic Cracking Process

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China Petroleum Processing & Petrochemical Technology 2022年第3期24卷 117-127页

作者： Long Jian Jiang Siyi Wang Wei Zhang feng Han Jifei fan Chen Key Laboratory of Smart Manufacturing in Energy Chemical Process Ministry of EducationEast China University of Science and TechnologyShanghai 200237China SINOPEC Jiujiang Company Jiujiang 332013China SINOPEC Research Institute of Petroleum Processing Beijing 100083China

Fluid catalytic cracking(FCC)is a vitally important refinery *** fractionation,absorption,and stabilization system in the FCC process is a significant way to obtain key products,and its parameters will directly affect the quality of the *** this work,using industrial data from an actual FCC process,a model of the FCC fractionation,absorption,and stabilization system was developed using process simulation *** sequence quadratic program algorithm was then used to identify the parameters of each tower,increasing the accuracy of the simulation ***,using this improved model,a sensitivity analysis was performed to examine the effects of different operating *** pattern-search method was then used to optimize the operating parameters of the *** results showed that the optimized model has good prediction accuracy,and using the model,it was found that changing the operation parameters could result in a 1.84%improvement in economic *** such,the developed model was demonstrated to be usefully applicable to the optimization of the process operation of an FCC fractionation,absorption,and stabilization system.

关键词： fluid catalytic cracking sequence quadratic program process modeling parameters identification patternsearch method

基于模糊综合评判法的长春市建设用地节约集约利用评价

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湖北农业科学 2017年第6期56卷 1173-1175,1178页

作者：关威李淑杰范晓锋梁珍玮孙博马晓葳吉林大学地球科学学院长春130061

基于模糊综合评判法,通过对长春市建设用地节约集约指标体系的研究,得出长春市区域建设用地节约集约利用程度。结果表明,长春市南关区、朝阳区集约程度为一级,榆树市、绿园区集约程度为二级,德惠市、双阳区集约程度为三级,九台市、农安... 详细信息

基于模糊综合评判法,通过对长春市建设用地节约集约指标体系的研究,得出长春市区域建设用地节约集约利用程度。结果表明,长春市南关区、朝阳区集约程度为一级,榆树市、绿园区集约程度为二级,德惠市、双阳区集约程度为三级,九台市、农安县、二道区、宽城区集约程度为四级。

关键词：节约集约利用模糊综合评判法建设用地长春市

Grain Shape Genes:Shaping the Future of Rice Breeding

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Rice science 2023年第5期30卷 379-404页

作者： LU Xuedan LI fan XIAO Yunhua WANG feng ZHANG Guilian DENG Huabing TANG Wenbang College of Agronomy Hunan Agricultural UniversityChangsha 410128China Hunan Provincial Key Laboratory of Rice and Rapeseed Breeding for Disease Resistance Changsha 410128China State Key Laboratory of Hybrid Rice Changsha 410125China Hunan Hybrid Rice Research Center Hunan Academy of Agricultural ScienceChangsha 410125China

The main goals of rice breeding nowadays include increasing yield,improving grain quality,and promoting complete mechanized production to save labor *** grain shape,specified by three dimensions,including grain length,width and thickness,has a more precise meaning than grain size,contributing to grain appearance quality as well as grain weight and thus ***,the divergence of grain shape characters could be utilized in mechanical seed sorting in hybrid rice breeding systems,which has been succeeded in utilizing heterosis to achieve substantial increase in rice yield in the past *** signaling pathways that regulate rice grain shape have been elucidated,including G protein signaling,ubiquitination-related pathway,mitogen-activated protein kinase signaling,phytohormone biosynthesis and signaling,micro RNA process,and some other transcriptional regulatory pathways and *** review summarized the recent progress on molecular mechanisms underlying rice grain shape determination and the potential of major genes in future breeding applications.

关键词： grain shape grain quality yield mechanization of seed sorting hybrid rice molecular function regulatory pathway

Low-power system model for quantum entangled photon-pair source

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Journal of Systems Engineering and Electronics 2024年第5期35卷 1287-1294页

作者： feng Tianxuan ZHANG Hanyi fan Rong MA Honghao DONG Mengcheng LI Lijing School of Instrumentation and Optoelectronic Engineering Beihang UniversityBeijing 100191China Engineering Training Center Beihang UniversityBeijing 102206China Beijing Aerospace Automatic Control Institute Beijing 100854China

The quantum entangled photon-pair source,as an essential component of optical quantum systems,holds great potential for applications such as quantum teleportation,quan-tum computing,and quantum *** current workhorse technique for preparing photon pairs involves performing spon-taneous parametric down conversion(SPDC)in bulk nonlinear ***,the current power consumption and cost of preparing entangled photon-pair sources are relatively high,pos-ing challenges to their integration and *** this paper,we propose a low-power system model for the quantum entan-gled photon-pair source based on SPDC theory and phase matching *** model allows us to analyze the per-formance of each module and the influence of component cha-racteristics on the overall *** our experimental setup,we utilize a 5 mW laser diode and a typical type-II barium metabo-rate(BBO)crystal to prepare an entangled photon-pair *** experimental results are in excellent agreement with the model,indicating a significant step towards achieving the goal of low-power and low-cost entangled photon-pair *** achievement not only contributes to the practical application of quantum entanglement lighting,but also paves the way for the widespread adoption of optical quantum systems in the future.

关键词： low-power system model optical quantum system entangled photon-pair source spontaneous parametric down conversion

本土化压力管理与心身增弹训练(SMART-C)对提升教师心理弹性与睡眠质量的作用研究

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世界睡眠医学杂志 2018年第7期5卷 808-812页

作者：王芳冯帆 John W.Denniger Herbert Benson Gregory L.Fricchione 中国中医科学院广安门医院睡眠心理科北京100053 哈佛大学医学院麻省总医院本森亨利心身医学研究所波士顿02114

目的:探索本土化压力管理心身增弹训练(SMART-C)对于教师群体的应对压力能力以及睡眠质量的改善作用,为进一步完善压力情绪管理应用于教育方案(RS-C)提供依据。方法:通过本土化压力管理心身增弹训练(SMART-C)对北京市东城区38位教师进... 详细信息

目的:探索本土化压力管理心身增弹训练(SMART-C)对于教师群体的应对压力能力以及睡眠质量的改善作用,为进一步完善压力情绪管理应用于教育方案(RS-C)提供依据。方法:通过本土化压力管理心身增弹训练(SMART-C)对北京市东城区38位教师进行干预,采用心理弹性量表、匹兹堡睡眠质量指数判定效果。结果:参与团体的教师在心理弹性的忍受消极情感和精神影响方面有所改善,睡眠方面在睡眠质量、入睡时间、睡眠时间、睡眠效率、日间功能等方面所有改善。结论:本土化压力管理心身增弹训练(SMART-C)对于教师群体的应对压力能力以及睡眠质量有改善作用。

关键词：本土化压力管理与心身增弹训练教师心身弹性睡眠质量

重症心力衰竭患者血清Adropin和炎性趋化因子水平变化及其与左心室重构和预后的关系

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热带医学杂志 2020年第4期20卷 530-533,541页

作者：范彩逢王振华张守彦马惠芳陈红英郑州大学附属洛阳中心医院心血管内科洛阳市心脑血管疾病研究所洛阳市心脑组织损伤与修复重点实验室河南洛阳471000 郑州大学附属洛阳中心医院超声科河南洛阳471000

目的探讨重症心力衰竭患者血清Adropin和炎性趋化因子水平变化及其与左心室重构和预后的关系。方法选取2017年3月至2018年11月郑州大学附属洛阳中心医院收治的重症心力衰竭(NYHA心功能Ⅱ级、Ⅲ级或Ⅳ级)患者128例行常规抗心力衰竭、厄... 详细信息

目的探讨重症心力衰竭患者血清Adropin和炎性趋化因子水平变化及其与左心室重构和预后的关系。方法选取2017年3月至2018年11月郑州大学附属洛阳中心医院收治的重症心力衰竭(NYHA心功能Ⅱ级、Ⅲ级或Ⅳ级)患者128例行常规抗心力衰竭、厄贝沙坦氢氯噻嗪以及美托洛尔片治疗,3个月1个疗程,患者均连续治疗2个疗程。检测患者治疗前、治疗1个疗程和治疗2个疗程的血浆脑钠肽(BNP)水平、血清Adropin水平、血清趋化因子(CXCL)10、CXCL12、CXCL16、白细胞介素-6(IL-6)等炎性趋化因子水平,以及左室射血分数(LVEF)、左心室舒张末期内径(LVEDD)、左心室收缩末期内径(LVESD)、左室短轴收缩率(LVFS)等左心室重构指标水平。统计患者不良心血管事件发生率。并分析患者血清Adropin和炎性趋化因子水平与其左心室重构指标水平以及不良心血管事件发生率的关系。结果与治疗前比较,患者治疗1个疗程和治疗2个疗程的血浆BNP水平、血清Adropin水平、血清CXCL10、CXCL12、CXCL16、IL-6水平以及LVEDD、LVESD均降低,同期LVEF、LVFS升高,差异均有统计学意义(P<0.05)。患者不良心血管事件发生率为16.41%(21/128)。与无不良心血管事件发生患者比较,发生不良心血管事件患者治疗前后的血清Adropin水平、血清CXCL10、CXCL12、CXCL16、IL-6水平均升高,差异均有统计学意义(P<0.05)。相关分析结果显示,重症心力衰竭患者血清Adropin和CXCL10、CXCL12、CXCL16、IL-6水平与血浆BNP水平、LVEDD、LVESD以及不良心血管事件发生率均呈正相关(Adropin:r=0.779、0.731、0.816、0.842;CXCL10:r=0.842、0.859、0.807、0.871;CXCL12:r=0.879、0.813、0.832、0.806;CXCL16:r=0.881、0.794、0.845、0.795;IL-6:r=0.802、0.819、0.872、0.883,P<0.05),与LVEF、LVFS则呈负相关(Adropin:r=-0.792、-0.778;CXCL10:r=-0.773、-0.779;CXCL12:r=-0.815、-0.843;CXCL16:r=-0.876、-0.889;IL-6:r=-0.818、-0.852,P<0.05)。结论重症心力衰竭患者血清Adropin和炎性趋化因子水平随着治疗的进行和病情的缓解而降低,且与患者左心室重构和预后均相关,可能作为其左心室重构和预后评估参考指标。

关键词：重症心力衰竭 Adropin 炎性趋化因子左心室重构预后

Zircon U-Pb Age,Geochemical,and Sr-Nd-Pb-Hf Isotopic Constraints on the Time Frame and Origin of Early Cretaceous Mafic Dykes in the Wuling Mountain Gravity Lineament,South China

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Acta Geologica Sinica(English Edition) 2021年第2期95卷 419-438页

作者： CHEN Xiaoqing LIU Shen feng Caixia XU Jingyan ZHAO Huibo feng Guangying Ian M.COULSON SUN Jinggui fan Yan College of Earth Sciences Jilin UniversityChangchun 130061China State Key Laboratory of Continental Dynamics and Department of Geology Northwest UniversityXi'an 710069China Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China Solid Earth Studies Laboratory Department of GeologyUniversity of ReginaReginaSaskatchewan S4S 0A2Canada

In view of the importance of mafic dyke swarms and their contribution to current scientific problems relating to South China,herein,we present the findings of studies on twenty–five representative mafic dykes cropping out in Hunan Province and Guangxi Zhuang Autonomous Region,within the southern Wuling Mountain gravity lineament,*** results include new zircon LA-ICP-MS U-Pb age,whole rock geochemical,Sr-Nd-Pb isotopic,and zircon Hf isotopic data for these *** dykes formed between 131.5±1.2 and 121.6±1.1 Ma,and have typical doleritic *** fall into the alkaline and shoshonitic series,are enriched in light rare earth elements(LREE),some large ion lithophile elements(LILE;e.g.,Rb,Ba,and Sr),Th,U,and Pb,and are depleted in Nb,Ta,Hf,and ***,the dolerites have high initial 87 Sr/86 Sr ratios(0.7055–0.7057),negativeεNd(t)and zirconεHf(t)values(-14.8 to-11.9,-30.4 to-14.9),and relatively constant initial Pb isotopic ratios(that are EM1-like,16.77–16.94,15.43–15.47,and 36.84–36.92 for 206 Pb/204 Pb,207 Pb/204 Pb,and 208 Pb/204 Pb,respectively).These results indicate that the dykes were likely derived from magma generated through low-degree partial melting(1.0%–10%)of an EM1-like garnet–lherzolite mantle *** parental magmas fractionated olivine,clinopyroxene,plagioclase,and Ti-bearing phases with negligible crustal contamination,during ascent and dyke *** possible models have been proposed to explain the origin of Mesozoic magmatism along the Wuling Mountain gravity *** we propose a reasonable model for the origin of these mafic dykes,involving the collision between the paleo-Pacific Plate and South China,which led to subsequent lithospheric extension and asthenosphere upwelling,resulting in partial melting the underlying mantle lithosphere in the Early Cretaceous,to form the parental magmas to the WMGL mafic dykes,as studied.

关键词： mafic dykes magmatic origin Early Cretaceous Wuling Mountain gravity lineament South China