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“双循环”战略实施对中国区域经济格局的影响——基于斯密分工思想的分析

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财经研究 2024年第3期50卷 4-18页

作者：刘军辉张古安虎森东北师范大学地理科学学院吉林长春130024 兰州大学经济学院甘肃兰州730000 南开大学经济研究所天津300071

文章以“双循环”战略为背景,在斯密分工思想的指引下,参考新兴古典理论关于分工的研究成果,基于新经济地理学理论的中间投入品模型和新增长理论的人力资本模型,融入由土地要素带来的拥塞效应,构建了具有“双循环”特征的区域经济模型,... 详细信息

文章以“双循环”战略为背景,在斯密分工思想的指引下,参考新兴古典理论关于分工的研究成果,基于新经济地理学理论的中间投入品模型和新增长理论的人力资本模型,融入由土地要素带来的拥塞效应,构建了具有“双循环”特征的区域经济模型,并在此基础上通过数值模拟和实证检验,分析中国区域经济格局演变的驱动力,研究了“双循环”战略实施对中国区域经济格局的影响。研究发现:(1)沿海地区和内陆地区的发展差距将经历“快速增加—较快下降—缓慢上升”的演变过程,并且这种差距在中期虽会收敛但不会消失,在后期甚至还有拉大的风险;(2)沿海地区和内陆地区的发展差距,与两个地区的对外交易效率和区域内部的交易效率密切相关,在分工原理作用下,这将演化出不同的区域产业结构,最终导致区域间的经济发展差距;(3)“双循环”战略的实施主要从交易效率方面影响中国的区域经济格局,因此缩小区域发展差距可从交易效率入手,借助产业链和产业集群,充分利用分工的作用来实现区域间的协调发展。研究结果表明,中国区域经济格局的形成是市场竞争下地域分工演化的结果,是斯密分工思想在区域经济中的体现。文章研究不仅巩固了区域经济关系分析的微观基础,还从数理和实证两方面证明了斯密分工思想的合理性,文章结论能够为“双循环”背景下空间经济问题的研究提供理论支撑。

关键词： “双循环”战略斯密定理区域经济格局南北差距新经济地理学

中原城市群交通基础设施建设对区域经济发展的空间溢出效应

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开发研究 2024年第3期 20-31页

作者：张凌玮安虎森东北师范大学地理科学学院长春130024 南开大学经济研究所天津300071

利用空间杜宾模型和中介效应模型对交通基础设施影响区域经济发展的空间溢出效应和作用机制进行了实证分析。结果表明,中原城市群高速交通网络的建设对区域经济发展的空间溢出效应显著,但不同类型的高速路网对该区域经济发展的影响存在... 详细信息

利用空间杜宾模型和中介效应模型对交通基础设施影响区域经济发展的空间溢出效应和作用机制进行了实证分析。结果表明,中原城市群高速交通网络的建设对区域经济发展的空间溢出效应显著,但不同类型的高速路网对该区域经济发展的影响存在较大的差异:高速公路建设对区域经济发展存在显著的负向的本地效应和空间溢出效应,高速公路建设加大了资源配置的扭曲,其市场整合效应也对现阶段中原城市群各城市经济发展造成了负向影响;高速铁路建设对中原城市群各城市经济发展存在显著的正向的本地效应和空间溢出效应,高速铁路的建设显著提升了劳动力配置效率,促进知识溢出提升了科技创新水平,推动了本地和邻近地区的经济发展。

关键词：交通基础设施本地市场效应空间溢出效应资源配置效应

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沿空留巷切顶爆破卸压技术研究与应用

煤 2024年第4期33卷 32-35页

作者：宋虎森武少鹏潞安化工集团安全管理部山西长治046204

针对长壁式采煤法基本顶破断,以及预留煤柱造成的资源浪费、巷道变形等问题,文章采用深孔预裂爆破切顶卸压技术,分析了工作面推进时顶板出现周期性垮落以及顶板应力分布特征,用预裂爆破技术在巷道上方和煤柱帮上方基本顶之间形成切缝,... 详细信息

针对长壁式采煤法基本顶破断,以及预留煤柱造成的资源浪费、巷道变形等问题,文章采用深孔预裂爆破切顶卸压技术,分析了工作面推进时顶板出现周期性垮落以及顶板应力分布特征,用预裂爆破技术在巷道上方和煤柱帮上方基本顶之间形成切缝,阻断基本顶之间的联系,消除采空区侧基本顶回转、断裂、垮落对煤柱侧的影响,使侧向支承压力峰值降低并向深部转移。研究表明,采用深孔预裂爆破切顶卸压技术后,顶底位移和两帮位移分别为190 mm和50 mm,切顶后的顶底位移与两帮位移比之前分别降低了71.2%和64.3%,由此可以看出,预裂爆破效果显著。该爆破方案的合理选择,不仅解决了采空区顶板压力与巷道变形较大的难题,还能有效地节省煤炭资源。

关键词：切顶爆破钻孔窥视矿压检测裂缝

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漳村煤矿井下充填开采方案设计

煤 2024年第9期33卷 58-61,71页

作者：宋虎森武少鹏潞安化工集团安全管理部山西长治046204

为了解决“三下一上”(建筑物下、铁路下、水体下和承压水体上)压煤、固体废弃物处理和开采损害等难题,选择以漳村煤矿为工程背景,通过理论分析、方案比较等方法,分析不同充填开采技术的适用性,最终设计采用膏体充填开采技术方案,并确... 详细信息

为了解决“三下一上”(建筑物下、铁路下、水体下和承压水体上)压煤、固体废弃物处理和开采损害等难题,选择以漳村煤矿为工程背景,通过理论分析、方案比较等方法,分析不同充填开采技术的适用性,最终设计采用膏体充填开采技术方案,并确定出矿井充填工艺及充填设备,能够满足矿井对有效回收“三下”煤炭资源和对地面沉降量控制的需求。

关键词：充填开采 “三下”压煤绿色开采技术地表沉降

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条带膏体充填开采覆岩移动规律研究——以高河能源为例

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煤 2024年第5期33卷 36-38,45页

作者：宋虎森武少鹏潞安化工集团安全管理部山西长治046204

为解决高河能源“三下”压煤开采问题,高河能源采用条带膏体充填回收边角煤资源。在系统阐述条带膏体充填的方案设计、巷道布置以及充填开采方法的基础上,给出了最优条带布置开采充填方案,并提出“掘顶—拉低—隔离—充填”的条带充填... 详细信息

为解决高河能源“三下”压煤开采问题,高河能源采用条带膏体充填回收边角煤资源。在系统阐述条带膏体充填的方案设计、巷道布置以及充填开采方法的基础上,给出了最优条带布置开采充填方案,并提出“掘顶—拉低—隔离—充填”的条带充填开采过程;基于E1312条带充填面布置条件构建FLAC3D数值模拟模型,分别对无充填开采与条带膏体充填开采过程进行模拟研究。结果表明:无填充开挖完成后覆岩下沉最大区域出现在开挖区域中部,表现出由中间向两侧呈拱形扩散的特征;条带膏体充填开采覆岩最大下沉值降低了57.97%,覆岩下沉形态为拱脚落在充填体上的连续拱形,覆岩裂隙带发育近似呈现“梯形”特征,能够有效控制煤层开采过程中的覆岩破坏移动。经分析研究表明,该技术可有效控制工作面开采过程中及采后覆岩运移破断,提高煤炭资源回收率,可为高河能源“三下”压煤资源开采与环境保护协调发展提供借鉴。

关键词： “三下”压煤条带膏体充填数值模拟覆岩运移

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Application of Silicon and Selenium in Rice for Reducing Cadmium Stress

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Phyton-International Journal of Experimental Botany 2023年第6期92卷 1873-1886页

作者： Mohammad Reza Boorboori husen Qiu Jieyun Liu Haiyang Zhang College of Environment and Surveying and Mapping Engineering Suzhou UniversitySuzhou234000China

Rice is an essential part of the human diet in most parts of the world;On the other hand,the industrialization of societies has led to pollution of the environment,including heavy metal contamination of soil and water,which negatively affects rice production and ***,finding ways to increase the yield and quality of this strategic crop seems *** studies have been conducted in recent decades to find effective and inexpensive solutions to reduce the adverse effects of heavy metals in rice *** to the negative effect of cadmium pollution on rice quality and yield,the current study aimed to investigate cadmium absorption and transfer mechanisms in rice(from absorption by roots to loading in grains),and its effects on rice morphology,physiology,and biochemistry(such as biomass,nutrient absorption,antioxidant defenses).Also,rice’s natural mechanisms for detoxifying cadmium were *** study also intended to identify the absorption and transfer pathways of silicon and selenium in rice,their roles in improving rice structures,and their antagonistic effects on reducing cadmium stress(absorption,transport,and toxicity of cadmium).

关键词： Oryza sativa L antagonism elements mechanism stress

Optimizing Energy Conservation in V2X Communications for 5G Networks

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Computers, Materials & Continua 2022年第5期71卷 3479-3495页

作者： Arif husen Abid Soahil Mohammad Hijji Muhammad Hasanain Chaudary Farooq Ahmed 无 Department of Computer Science COMSATS University IslamabadLahore CampusLahorePunjabPakistan Department of Computer Science and Information Technology Virtual University of PakistanLahorePunjabPakistan Computer Science Department University of TabukTabukSaudi Arabia

The smart vehicles are one of critical enablers for automated services in smart cities to provide intelligent transportation means without human *** order to fulfil requirements,Vehicle-to-Anything(V2X)communications aims to manage massive connectivity and high traffic load on base stations and extend the range over multiple hops in 5G ***,V2X networking faces several challenges from dynamic topology caused by high velocity of nodes and routing overhead that degrades the network performance and increases energy *** existing routing scheme for V2X networking lacks energy efficiency and scalability for high velocity nodes with dense *** order to handle the challenges,this article proposes a scalable and energy-efficient routing scheme called Dynamic proactive reactive routing for 5G(DPR5)for high mobility speed and dense *** compared to existing schemes it uses a single routing table and efficiently minimizes the energy consumption in dense environment,improves node‘s lifetime upto 42%,and optimizes network performance by reducing the packet loss ratio upto 46%in a high velocity dense environment.

关键词： Internet of vehicles vehicle-to-any device energy conservation

Using pyrosequencing and quantitative PCR to analyze microbial communities

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Frontiers of Environmental Science & Engineering 2011年第1期5卷 21-27页

作者： husen ZHANG Department of Civil Environmentaland Construction EngineeringUniversity of Central FloridaOrlandoFL 32816USA

New high-throughput technologies continue to emerge for studying complex microbial *** particular,massively parallel pyrosequencing enables very high numbers of sequences,providing a more complete view of community structures and a more accurate inference of the functions than has been possible just a few years *** parallel,quantitative real-time polymerase chain reaction(QPCR)allows quantitative monitoring of specific community members over time,space,or different environmental *** this review,the principles of these two methods and their complementary applications in studying microbial ecology in bioenvironmental systems are *** parallel sequencing of amplicon libraries and using barcodes to differentiate multiple samples in a pyrosequencing run are *** best procedures and chemistries for QPCR amplifications are also described and advantages of applying automation to increase accuracy are *** examples in which pyrosequencing and QPCR were used together to define and quantify members of microbial communities are provided:in the human large intestine,in a methanogenic digester whose sludge was made more bioavailable by a high-voltage pretreatment,and on the biofilm anode of a microbial electrolytic *** key findings in these systems and how both methods were used in concert to achieve those findings are highlighted.

关键词： polymerase chain reaction(PCR) microbial communities pyrosequencing gut microbial fuel cell sludge

Walnut Staminate Flowers Can Be Explored as a Supplementary Plant Oil Source

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Journal of Integrative Plant Biology 2006年第4期48卷 377-380页

作者： husen Jia Yinong Xu Key Laboratory of Photosynthesis and Environmental Molecular Physiology Institute of Botany the Chinese Academy of Sciences Beijing 100093 China

Fossil fuel Is currently the major energy source driving global socio-economy, but its stock Is being heavily depleted due to Increasing anthropogenic activities worldwide. There are also concerns regarding the burning of fossil fuels, which contributes to global climate warming and sir pollution. As such, the development of blodlesel as a non-toxic, blodegredable, and renewable alternative energy source using oil crops such as soybean and rapeseed has quickly emerged in the West countries. However, the production of oil crops In China Is far from sufficient to meet the demands of the country＇s population of 1.3 billion, and Increasing oil crop production Is Inhibited by a severe shortage of agricultural land, which currently averages 0.2 acre per person and, as such, Is less than half the world average. The current national policy in China regarding land use Is more towards revering cultivated lands in revins and hills to forestry, which presents an ideal opportunity to further develop plantations of walnut （Juglans regis L.） trees, a plant that is tolerant to drought and infertile soils and has a high oil content. Study In this paper shows that one ament of walnut staminate flowers produces about 0.168 g dry pollen, and the dry pollen contained 49.67% oil. Based on this discovery, oil yield obtained from staminate flowers Is estimated to reach 6.95% of that from walnut nuts. Thus walnut staminate flower is suggested to explore as supplementary plant oil source, and has a great opportunity to utilize as a biodlesel feedstock.

关键词： biodiesel feedstock oil walnut staminate flowers.