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统一大市场的共同富裕效应研究

现代经济探讨 2024年第2期 14-26页

作者：张晖陈建行海南大学国际商学院海南大学海南省开放型经济研究院海口570228

全国统一大市场建设不仅是中国经济高质量发展的必由之路,也是促进全体人民共同富裕的内在要求。基于2006-2019年城市面板数据,构建共同富裕指标体系,实证检验市场一体化对共同富裕的影响效应。研究表明,提高市场一体化程度有助于促进... 详细信息

全国统一大市场建设不仅是中国经济高质量发展的必由之路,也是促进全体人民共同富裕的内在要求。基于2006-2019年城市面板数据,构建共同富裕指标体系,实证检验市场一体化对共同富裕的影响效应。研究表明,提高市场一体化程度有助于促进共同富裕的实现,统一大市场建设具有共同富裕效应,这一结论经过各种稳健性检验以及缓解内生性问题后仍然成立。机制分析表明,市场一体化主要是通过提高劳动和资本要素配置效率,推动区域创新创业,进而促进共同富裕。异质性分析表明,在东部地区和城市群地区,市场一体化对共同富裕的促进作用更明显。该研究结果为地方政府加快统一大市场建设提供了重要的经验证据和政策参考,对加快共同富裕进程有着重要意义。

关键词：市场一体化共同富裕创新创业资源配置效率

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统一大市场的绿色之路--基于空气质量视角

科技管理研究 2024年第3期44卷 227-235页

作者：张晖陈建行海南大学国际商学院海南海口570228

为探究统一大市场的绿色之路,基于2001—2019年城市数据,采用面板回归模型探讨空气质量对市场一体化的影响,并构建多期双重差分(DID)模型探究《环境空气质量标准(2012)》政策对市场一体化的影响。研究表明,空气质量改善有利于市场一体... 详细信息

为探究统一大市场的绿色之路,基于2001—2019年城市数据,采用面板回归模型探讨空气质量对市场一体化的影响,并构建多期双重差分(DID)模型探究《环境空气质量标准(2012)》政策对市场一体化的影响。研究表明,空气质量改善有利于市场一体化形成,该结论经过一系列的稳健性检验和内生性检验依然成立;在非城市群城市和东部地区空气质量改善对市场一体化的促进作用更为明显;商品流通程度、劳动力流动和资本流动是空气质量影响国内市场一体化的重要渠道;进一步分析发现,《环境空气质量标准(2012)》的实施,能够有效地降低市场分割程度,促进市场一体化。研究结果为进一步探索市场一体化的绿色路径提供参考,为地方政府推进绿色发展和建设市场一体化提供理论和经验证据。

关键词：空气质量市场一体化环境空气质量标准双重差分(DID)

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含水率影响下煤体巴西劈裂特性与弱化机制

采矿与安全工程学报 2024年第2期41卷 362-371页

作者：张村王磊王潇杰刘金保崔舒畅陈见行中国矿业大学(北京)共伴生能源精准开采北京市重点实验室北京100083 中国矿业大学(北京)能源与矿业学院北京100083 中国矿业大学(北京)厚煤层绿色智能开采教育部工程研究中心北京100083

利用废弃矿井采空区作为储水空间对矿区生态环境和经济发展具有重要作用,但在不同含水率影响下,煤岩体强度会出现一定的弱化,进而影响地下储库的稳定性。以关闭的大台矿井-710 m开采水平3#煤层煤样为研究对象,研究不同含水率煤样巴西劈... 详细信息

利用废弃矿井采空区作为储水空间对矿区生态环境和经济发展具有重要作用,但在不同含水率影响下,煤岩体强度会出现一定的弱化,进而影响地下储库的稳定性。以关闭的大台矿井-710 m开采水平3#煤层煤样为研究对象,研究不同含水率煤样巴西劈裂强度弱化程度、劈裂破坏特征和声发射演化规律;借助CT扫描浸水前后煤样孔隙特征,探究其内在影响机制。研究结果表明:干燥煤样圆盘表面的主要裂纹沿劈裂面存在,而饱和煤样的裂纹偏离劈裂面,形成许多不规则的剪切裂纹。随着含水率的增加,圆盘表面劈裂裂隙平整度降低,从干燥到饱和,裂隙分形维数由1.066升高至1.298;煤样抗拉强度随含水率增加呈线性减小,但峰值应变则呈先增大后减小的抛物线变化;煤样声发射累计计数随含水率增加而逐渐减小,破坏阶段低含水率煤样产生张拉为主的拉剪复合裂隙且尺度较大,高含水率煤样产生小尺度张拉裂隙。煤样浸水后原生裂隙扩张,孔隙率提高2.55%,煤样孔隙率升高使煤样损伤发育加速,进而导致在劈裂过程中更易形成贯通裂隙;水的存在弱化了原生裂隙胶结强度,使劈裂裂隙沿强度较小的节理裂隙面扩张,初始劈裂面粗糙度增加。新增裂隙的减小也同样使声发射强度降低。

关键词：废弃矿井含水率巴西劈裂抗拉强度声发射弱化机制

Parametric study on the axial performance of a fully grouted cable bolt with a new pull-out test

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International Journal of Mining Science and Technology 2016年第1期26卷 53-58页

作者： chen jianhang Hagan Paul C. Saydam Serkan School of Mining Engineering University of New South Wales

Modified cable bolts are commonly used in underground mines due to their superior performance in preventing bed separation when compared with plain strands. To better test the axial performance of a wide range of cable bolts,a new laboratory short encapsulation pull test(LSEPT) facility was developed. The facility simulates the interaction between cable bolts and surrounding rock mass,using artificial rock cylinders with a diameter of 300 mm in which the cable bolt is grouted. Furthermore,the joint where the load is applied is left unconstrained to allow shear slippage at the cable/grout or grout/rock interface.Based on this apparatus,a series of pull tests were undertaken using the MW9 modified bulb cable bolt.Various parameters including embedment length,test material strength and borehole size were evaluated. It was found that within a limited range of 360 mm,there is a linear relationship between the maximum bearing capacity of the cable bolt and embedment length. Beyond 360 mm,the peak capacity continues to rise but with a much lower slope. When the MW9 cable bolt was grouted in a weak test material,failure always took place along the grout/rock interface. Interestingly,increasing the borehole diameter from 42 to 52 m in weak test material altered the failure mode from grout/rock interface to cable/grout interface and improved the performance in terms of both peak and residual capacity.

关键词：锚索灌浆性能参数锚索注浆拉拔试验轴向岩石界面试验材料钻孔直径

Movement and deformation laws of the overlying strata in paste filling stope

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Mining Science and Technology 2011年第6期21卷 863-868页

作者： Xu Ying Chang Qingliang Zhou Huaqiang Cao Zhong Li Xiushan chen jianhang School of Mines China University of Mining ＆ Technology Xuzhou 22116 China State Key Laboratory of Coal Resources and Mine Safety China University of Mining ＆ Technology Xuzhou 221116 China Daizhuang Mine of Shandong Energy Zibo Mining Group Co. Ltd. Jining 272000 China

We combined the similar simulation with numerical simulation to analyze the movement and deforma- tion features of overlying strata caused by paste backfill mining, study the movement and deformation laws of the overlying strata in paste backfill mining, structural movement of the stope strata as well as the stope stress distribution laws. Furthermore, authors also explored the key factors to the movement and deformation of the overlying strata in paste backfill mining. The results indicate that a caving zone existed in the bending zone only in the overlying strata of the paste backfill mining. Compared with the roof caving mining, the degree of stress concentration and area of influence in the paste filling stope were apparently smaller. And the degree of destruction and area of the overlying strata decreased prominently. Also, there was no apparent strata behavior in the working face. Lastly, the filling ratio was the key to control the movement and deformation of the overlying strata. Combined with a specific engineering example, the author proved the reliability of the simulation results and provided a theoretical basis for the further extension of the paste backfill mining.

关键词：充填开采变形规律岩层运动采场充填应力分布规律地层变形数值模拟覆岩运动

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数值分析课程线上授课方式探索

创新创业理论研究与实践 2024年第8期7卷 55-57,96页

作者：陈见行王世纪中国矿业大学(北京)能源与矿业学院北京100083

数值分析是采矿工程专业的一门课程,包括理论授课和上机实验两个部分。但受一些突发情况影响,包括多媒体损坏、教学区断电等,学生可能无法进行线下学习。因此,该文设计了“微信群+腾讯会议+超星学习通”相结合的方式展开线上授课,针对... 详细信息

数值分析是采矿工程专业的一门课程,包括理论授课和上机实验两个部分。但受一些突发情况影响,包括多媒体损坏、教学区断电等,学生可能无法进行线下学习。因此,该文设计了“微信群+腾讯会议+超星学习通”相结合的方式展开线上授课,针对理论知识和上机实验分别制定了相应的授课方案,课程结束之后,分别从学生成绩、学生评教、督导评价等方面进行评价。结果表明:采用线上授课的方式能够顺利完成对该课程的讲授。

关键词：教学改革线上授课上机实验学生评教数值分析实践教学

Exhumation of the Late Cretaceous Ore-forming Porphyries in Zhongdian Area,Northwestern Yunnan:Evidence from Fission Track Analysis

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Acta Geologica Sinica(English Edition) 2021年第5期95卷 1786-1787页

作者： LIU Xuelong YANG Zhiming LU Yingxiang ZHANG Na DONG Leilei JIAO Qianqian chen jianhang YANG Fucheng Kunming University of Science and Technology Kunming 650093China Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China Yunnan Geological Survey Kunming 650051China China University of Geosciences Beijing 100083China

Objective The Zhongdian area,Yunnan Province,is located in the southern of the Yidun Island arc belt in the TethysHimalayan metallogenic area,and is one of the important copper polymetallic mineral resource bases in China.Based on the previous studies(Liu et al.,2014),this paper discusses the Late Cretaceous tectono-thermal events in Zhongdian,to reconstruct the framework of their evolution and to restore the uplift history of representative ore-forming porphyries.

关键词： Cretaceous China. bases

Comparative study of big data of global adakites and mineralization-related granite in the Geza arc metallogenic belt, northwest Yunnan, Southwest China

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Big Earth Data 2018年第3期2卷 268-281页

作者： Liu Xuelong Li Wenchang Zhang Qi Zhang Na Zhang Changzhen Luo Ying Wang Shuaishuai Yang Fucheng chen jianhang Li Zhenhuan Faculty of Land and Resource Engineering Kunming University of Science and TechnologyKunmingChina Key Laboratory of Geological Information Technology Ministry of Natural Resources of the People’s Repbulic of ChinaBeijingChina chengdu Geological Survey Center China Geological SurveyChengduChina Institute of Geology and Geophysics Chinese Academy of SciencesBeijingChina

The Geza arc is an important part of the Sanjiang tectono-magmatic belt and is a newly discovered copper polymetallic ore concentration area in northwest Yunnan province,Southwest China.The area comprises numerous metal ore deposits,including one super-largedeposit,three large deposits,etc.The formation of these deposits was closely related to intermediate–acidic magmatic intrusions.Based on previous studies,the“big data”analysis technique was used for a comparative study of large geochemical datasets of granite related to ore-formation in the Geza porphyry copper deposit and global adakites.As a result,1313 element combinations and 127,765 overlap ratios were obtained.The results show that the Geza porphyry has similar geochemical characteristics to global adakites(the ratios of REE and Ga to major elements are in the range of global adakites).However,theCu,Mo,and Zn contents of the porphyry are significantly higher than those of global adakites,and the porphyry may,therefore,represent an end-member of the global range of adakite composition.In addition,the geochemistry of adakites associated with the porphyry copper deposits overlaps in part with that of global adakites,although most of the data lie outside of the range of global adakites(i.***.lowMn/Cu,Sr/Cu,Na/Cu,and Zr/Cu values,and high Th/Cu,Ba/Cu,Na/Mo,Rb/Mo,Th/Mo,Ta/Mo,Ba/Mo,Mn/Zn,and Ba/Znvalues).The samples with characteristics that deviate significantly from the geochemistry of global adakites show more advanced mineralization and alteration,and a stronger relationship with Cu and Momineralization.The results of geochemical data mining can be used as a prospecting indicator,and provide a new scientific basis for geological prospecting of the deep levels and per-iphery of the Geza Cu polymetallic ore belt.

关键词： Porphyry Cu deposit granite adakite geochemistry confidence ellipses overlapping ratio geological big data Sanjiang area

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超大断面矩形顶管姿态控制关键技术研究

广东土木与建筑 2024年第7期31卷 32-35页

作者：郭平李茂陈建航吴祥吕庆龙苏栋中电建南方建设投资有限公司深圳518052 深圳大学土木与交通工程学院深圳518060 中国水利水电第十一工程局有限公司郑州450001 滨海城市韧性基础设施教育部重点实验室(深圳大学) 深圳518060 深圳市地下车站绿色高效智能建造重点实验室深圳518060

针对深圳某地铁站矩形顶管隧道工程的超大断面、浅覆土、密贴顶进等特点,对顶管姿态控制难点进行分析,并对该工程采用的姿态测量、铰接纠偏、多螺旋机出土、多刀盘模式控制、注浆纠偏等多种技术结合的纠偏控制方案进行介绍。根据该工程... 详细信息

针对深圳某地铁站矩形顶管隧道工程的超大断面、浅覆土、密贴顶进等特点,对顶管姿态控制难点进行分析,并对该工程采用的姿态测量、铰接纠偏、多螺旋机出土、多刀盘模式控制、注浆纠偏等多种技术结合的纠偏控制方案进行介绍。根据该工程实践表明:①顶管姿态偏移主要源于顶管开挖面及隧道两侧水土压力不平衡;②矩形顶管姿态控制重点是水平姿态以及垂直姿态控制;③通过采用铰接油缸控制、注浆纠偏、多螺旋机出土、多刀盘转动模式控制等技术,可有效控制顶管姿态。

关键词：矩形顶管隧道超大断面密贴顶进姿态控制铰接纠偏