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Experimental investigation on using CO_(2)/H_(2)O emulsion with high water cut in enhanced oil recovery

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Petroleum Science 2024年第2期21卷 974-986页

作者： Xi-dao Wu Peng Xiao Bei Liu guang-Jin Chen Jian-Hua Pang State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing102249China Ocean Intelligence Technology Center Shenzhen Institute of Guangdong Ocean UniversityShenzhen518120GuangdongChina

CO_(2) emulsions used for EOR have received a lot of interest because of its good performance on CO_(2)mobility ***,most of them have been focusing on the high quality CO_(2) emulsion(high CO_(2) fraction),while CO_(2) emulsion with high water cut has been rarely *** this paper,we carried out a comprehensive experimental study of using high water cut CO_(2)/H_(2)O emulsion for enhancing oil ***,a nonionic surfactant,alkyl glycosides(APG),was selected to stabilize CO_(2)/H_(2)O emulsion,and the corresponding morphology and stability were evaluated with a transparent PVT ***,plugging capacity and apparent viscosity of CO_(2)/H_(2)O emulsion were measured systematically by a sand pack displacement apparatus connected with a 1.95-m long capillary ***,a high water cut(40 vol%) CO_(2)/H_(2)O emulsion was selected for flooding experiments in a long sand pack and a core sample,and the oil recovery,the rate of oil recovery,and the pressure gradients were *** results indicated that APG had a good performance on emulsifying and stabilizing CO_(2) *** inversion from H_(2)O/CO_(2) emulsion to CO_(2)/H_(2)O emulsion with the increase in water cut was ***_(2)/H_(2)O emulsions with lower water cuts presented higher apparent viscosity,while the optimal plugging capacity of CO_(2)/H_(2)O emulsion occurred at a certain water ***,the displacement using CO_(2)/H_(2)O emulsion provided 18.98% and 13.36% additional oil recovery than that using pure CO_(2) in long sand pack and core tests,*** work may provide guidelines for EOR using CO_(2) emulsions with high water cut.

关键词： CO_(2)/H_(2)O emulsion High water cut CO_(2) mobility control Enhanced oil recovery

Description of a new species of the genus Uropsilus(Eulipotyphla:Talpidae:Uropsilinae)from the Dabie Mountains,Anhui,Eastern China

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Zoological Research 2021年第3期42卷 294-299页

作者： Ting-Li Hu Zhen Xu Heng Zhang Ying-Xun Liu Rui Liao guang-dao yang Ruo-Lei Sun Jie Shi Qian Ban Chun-Lin Li Shao-Ying Liu Bao-Wei Zhang School of Life Science Anhui UniversityHefeiAnhui 230601China Sichuan Academy of Forestry ChengduSichuan 610081China Forestry Investigation and Planning Institute of Anhui Province HefeiAnhui 230001China

During a terrestrial vertebrate survey of the Dabie Mountains in Anhui Province,eastern China,we collected four Asian shrew mole specimens(hereafter,shrew moles).Based on published literature and comparison with previously collected materials,the four specimens were similar to shrew moles from the mountains of Southwest China;however,no species in this group has been previously recorded from the Dabie *** genetic and morphological characteristics of the specimens were analyzed,based upon which a new species of shrew mole is described,named Uropsilus dabieshanensis ***.

关键词： Anhui Eastern mountains

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高速平滑S曲线加减速速度控制算法研究

控制工程 2017年第10期24卷 2053-2058页

作者：许光彬余道洋阜阳职业技术学院工程科技学院安徽阜阳236016 合肥工业大学机械与汽车工程学院合肥230009

针对S型曲线加减速算法的加加速度曲线是阶跃变化的,即其存在拐点,在高速加工过程中容易引起数控机床的冲击与振动,提出了能避免加加速度阶跃变化的平滑S型曲线加减速控制算法,根据曲线长度将平滑S型曲线加减速控制分为完整平滑加减速... 详细信息

针对S型曲线加减速算法的加加速度曲线是阶跃变化的,即其存在拐点,在高速加工过程中容易引起数控机床的冲击与振动,提出了能避免加加速度阶跃变化的平滑S型曲线加减速控制算法,根据曲线长度将平滑S型曲线加减速控制分为完整平滑加减速过程和不完整平滑加减速过程,并都建立了详细的算法。最后用流量计转子截面曲线摆线段作为实例并与S曲线加减速控制算法进行了仿真对比,验证该算法的正确性。验证结果表明:该算法不仅可保证速度和加速度连续,而且加加速度也呈线性规律变化,避免了加减速过程中的加加速度阶跃现象,提高了数控系统加减速平滑性、柔性。

关键词：平滑 S曲线加减速加加速度非完整平滑加减速

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企业资源配置战略与债券信用评级

财经问题研究 2024年第2期 64-75页

作者：张新民丁璇杨道广对外经济贸易大学国际商学院北京100029 对外经济贸易大学北京企业国际化经营研究基地北京100029

企业战略作为企业全局性、长期性资源配置的重要规划,对企业经营活动具有重要影响,也必然会影响企业的融资行为。本文从企业战略视角出发,以2008—2020年中国A股上市公司为研究对象,运用固定效应模型探究了企业资源配置战略对债券信用... 详细信息

企业战略作为企业全局性、长期性资源配置的重要规划,对企业经营活动具有重要影响,也必然会影响企业的融资行为。本文从企业战略视角出发,以2008—2020年中国A股上市公司为研究对象,运用固定效应模型探究了企业资源配置战略对债券信用评级的影响。研究发现:相对于经营主导型企业,投资主导型企业的债券信用评级更低,并且该结论在处理内生性问题和进行一系列稳健性检验后依然成立。异质性分析发现,企业资源配置战略对债券信用评级的影响在非国有企业和分析师跟踪人数多的企业中更明显。中介效应检验结果表明,企业资源配置战略通过作用于企业违约风险而影响债券信用评级。本文的研究结论对发债企业、信用评级机构和债券市场投资者具有重要启示意义。

关键词：企业资源配置战略债券信用评级企业违约风险投资主导型企业经营主导型企业

A novel refined dynamic model of high-speed maglev train-bridge coupled system for random vibration and running safety assessment

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Journal of Central South University 2024年第7期31卷 2532-2544页

作者： MAO Jian-feng LI dao-hang YU Zhi-wu CAI Wen-feng GUO Wei ZHANG guang-wen School of Civil Engineering Central South UniversityChangsha 410075China National Engineering Research Center of High-speed Railway Construction Technology Changsha 410075China China Railway Group Limited Beijing 100039China China Railway Eryuan Engineering Group Co. Ltd.Chengdu 610031China

Running safety assessment and tracking irregularity parametric sensitivity analysis of high-speed maglev train-bridge system are of great concern,especially need perfect refinement models in which all properties can be well characterized based on various stochastic excitations.A three-dimensional refined spatial random vibration analysis model of high-speed maglev train-bridge coupled system is established in this paper,in which multi-source uncertainty excitation can be considered simultaneously,and the probability density evolution method(PDEM)is adopted to reveal the system-specific uncertainty dynamic *** motion equation of the maglev vehicle model is composed of multi-rigid bodies with a total 210-degrees of freedom for each vehicle,and a refined electromagnetic force-air gap model is used to account for the interaction and coupling effect between the moving train and track beam bridges,which are directly established by using finite element *** model is proven to be applicable by comparing with Monte Carlo *** applying the proposed stochastic framework to the high maglev line,the random dynamic responses of maglev vehicles running on the bridges are studied for running safety and stability ***,the effects of track irregularity wavelength range under different amplitude and running speeds on the coupled system are *** results show that the augmentation of train speed will move backward the sensitive wavelength interval,and track irregularity amplitude influences the response remarkably in the sensitive interval.

关键词： maglev train-bridge interaction electromagnetic force-air gap model stochastic dynamic analysis running safety assessment probability density evolution method

U-Pb dating of monazite in the Bainiuchang silver polymetallic deposit,Yunnan Province,and its limitation on Mesozoic mineralization

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China Geology 2024年第3期7卷 592-595页

作者： Bo-de Lu Wen-chang Li Xue-long Liu guang-zhi Meng Qi-he Long Hong Zhang Jun-shan dao Fang-lan Li Jie-hu Zhou Mao-huang Fan Xue Mi Nan Shi Zhen-liang Cao College of Land Resources and Engineering Kunming University of Science and TechnologyKunming 650093China Geological Team 306 of Yunnan Non-ferrous Metals Geological Bureau Kunming 650217China Mengzi Mining and Metallurgy Co. Ltd.Mengzi 661199China

*** The Gejiu-Bozhushan-Laojunshan tin-tungsten polymetallic metallogenic belt is located in southeastern *** is bounded by the Mile-Shizong Fault and the yangzi Plate to the north and west,respectively,while the Honghe Fault represents its southwestern *** is adjacent to the Ailaoshan Fault,and extends to guangxi and Vietnam to the southeast(Fig.1a;Liu JP et al.,2021).

关键词： silver dating southeast

响应面法优化暗紫贝母流浸膏提取工艺及其质量评价

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天然产物研究与开发 2024年第9期36卷 1554-1563页

作者：张亚梅韩鸿萍宋道光青海师范大学化学化工学院西宁810008 青海省青藏高原药用动植物资源重点实验室西宁810016

优化暗紫贝母流浸膏提取工艺,评价暗紫贝母流浸膏质量。以总生物碱含量、贝母辛含量、贝母素甲、贝母素乙和西贝母碱三碱含量之和、浸膏得率的综合评分作为评价指标,采用单因素实验确定乙醇体积分数、乙醇用量、浸润时间、渗漉速度4个... 详细信息

优化暗紫贝母流浸膏提取工艺,评价暗紫贝母流浸膏质量。以总生物碱含量、贝母辛含量、贝母素甲、贝母素乙和西贝母碱三碱含量之和、浸膏得率的综合评分作为评价指标,采用单因素实验确定乙醇体积分数、乙醇用量、浸润时间、渗漉速度4个因素对暗紫贝母流浸膏提取的影响;利用Box-Benhnken响应面法确定并验证暗紫贝母流浸膏的最优渗漉提取工艺条件;采用薄层色谱法对暗紫贝母药材进行定性鉴别,并对其水分、灰分及浸出物进行检查;采用薄层色谱建立暗紫贝母流浸膏中贝母辛、贝母素乙的定性鉴别方法,并对其乙醇量和重金属进行检查。结果表明暗紫贝母流浸膏的最佳提取工艺为:乙醇体积分数为70%,乙醇用量为18倍,浸润时间为39 h,渗漉速度为3 mL/(kg·min),在此条件下暗紫贝母流浸膏综合评分为(89.97±1.90)%。药材和流浸膏TLC结果斑点清晰,分离度好,药材水分不超过15%、灰分不超过5.0%及浸出物大于9.0%,暗紫贝母流浸膏的乙醇量和重金属检查均符合《中华人民共和国药典》流浸膏制剂规定。本研究优化的暗紫贝母流浸膏提取工艺稳定可行,为暗紫贝母开发利用提供参考。

关键词：暗紫贝母流浸膏响应面提取工艺质量评价

孝昌周巷镇茶产业高质量发展助推乡村振兴的调查与思考

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湖北职业技术学院学报 2024年第2期27卷 7-11页

作者：叶道光湖北工业大学湖北武汉430068

产业兴旺是乡村振兴的重要基础,是解决农村一切问题的前提。孝昌县周巷镇立足资源禀赋,抢抓发展机遇,用足用活各类政策,因势利导发展壮大茶产业,成为当地推进乡村振兴的新引擎。面对机遇和挑战,周巷镇仍然需要准确识变、科学应变、主动... 详细信息

产业兴旺是乡村振兴的重要基础,是解决农村一切问题的前提。孝昌县周巷镇立足资源禀赋,抢抓发展机遇,用足用活各类政策,因势利导发展壮大茶产业,成为当地推进乡村振兴的新引擎。面对机遇和挑战,周巷镇仍然需要准确识变、科学应变、主动求变,不断破解土地、人才、技术、资金等要素制约,坚持市场思维、运用市场办法,加强品牌建设,走集约化、规模化发展之路。

关键词：乡村特色产业高质量发展乡村振兴

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多孔介质低渗测试气体周期振荡法理论研究

岩土力学 2024年第7期45卷 1939-1956页

作者：王威陈卫忠杨典森杨光华周小文袁明道史永胜刘宜杰广东省水利水电科学研究院广东广州510610 广东省岩土工程技术研究中心广东广州510640 华南理工大学土木与交通学院广东广州510640 中国科学院武汉岩土力学研究所岩土力学与工程国家重点实验室湖北武汉430071 武汉大学土木建筑工程学院湖北武汉430072

目前,多孔介质低渗测试主要采用高精度气体稳态法和气体脉冲衰减法,缺少对气体周期振荡法的深入探讨和分析。基于气体周期振荡法基本原理和试验方法,提出了3种基于不同控制方式模拟生成周期波气压边界条件的方法,以及在试样上游和下游... 详细信息

目前,多孔介质低渗测试主要采用高精度气体稳态法和气体脉冲衰减法,缺少对气体周期振荡法的深入探讨和分析。基于气体周期振荡法基本原理和试验方法,提出了3种基于不同控制方式模拟生成周期波气压边界条件的方法,以及在试样上游和下游分别设置1个体积可调的气体储存容器的试验设备方案。基于孔隙流体介质的讨论,将Fischer等提出的以不可压缩流体为渗流介质的周期法理论解,推广到以可压缩流体为渗流介质的情况,扩大了周期法理论解的适用范围,并讨论了各参数之间的物理意义及其联系。基于气体周期振荡法理论解,进行了2个特例分析,优化了理论解中复杂分项的处理。通过一系列正交对照计算案例,对比了气体周期振荡法理论解和数值解的计算结果,讨论了渗透率、孔隙率、下游容器体积、试样直径和长度等对试验过程的影响,验证了理论解的准确性和可靠性,并对理论解的不足进行了说明,在此基础上,给出了气体周期振荡法试验的优化设计策略。

关键词：气体周期振荡法渗透率储存系数理论研究