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Petroleum Science 2019年第2期16卷 447-457页

作者： Liangyu Xia Yujie Yin Xin Yu yuhua zheng School of Economic and Management China University of Petroleum-Beijing Information Technology Center BGP CNPC

The heterogeneity of coalbed methane(CBM) resources was not taken into account when the current indiscriminate subsidy policy was developed. In it, limited subsidy funds are given first to high-quality resources and even to subsidize profitable projects. Thus, the policy has had less than the intended effect in improving CBM production. To implement a new type of differential subsidy, it is necessary to grade the CBM resources, as will be discussed in this paper. After the factors affecting the resources value are systemically examined, sorted and merged, the relationship between the key factors and economic value is analyzed by an engineering economics method, and the production profile type, peak production(or stable production) and buried depth are used as grading factors. The production profile type is used to categorize, and peak production and buried depth are used to grade resources within the same category. The grading method is as follows: use subsidy levels at the economic critical point(NPV = 0) to identify the grades of resources, and determine the combination of peak production and buried depth for different resources grades base on indifference curves drawn according to the relationship between the economic value and peak production and buried depth.

关键词： Coalbed methane Production profile type Peak production Buried depth Differential subsidies

Magnetic activated carbon for the removal of methyl orange from water via adsorption and Fenton-like degradation

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Particuology 2024年第11期94卷 314-326页

作者： Qianyu Wang Yuming Zhang yuhua zheng Emmanuel Oluwaseyi Fagbohun Yanbin Cui State Key Laboratory of Heavy Oil Processing China University of Petroleum(Beijing)Beijing102249China State Key Laboratory of Mesoscience and Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing100190China Laboratory for Nanomaterials and Molecular Plasmonics Department of Chemistry and BiologyToronto Metropolitan University350 Victoria StTorontoONM5B2K3Canada

Water pollution caused by organic dyes is a critical environmental *** activated carbon(AC)is commonly used for dye adsorption,its effectiveness is limited by challenges in separation and *** address these limitations,a convenient recyclable magnetic activated carbon(MAC)was fabricated via co-precipitation and calcination method,serving as adsorbent and catalyst for methyl orange(MO)removal through a Fenton-like degradation *** techniques,including XRD,FTIR,SEM and TEM,confirmed that Fe_(3)O_(4) nanoparticles(10–20 nm)were uniformly dispersed on AC *** MAC maintaining a high surface area(997 m^(2)/g)and pore volume(0.795 cm^(3)/g)and exhibited superparamagnetic properties with a saturated magnetization of 5.52 emu/g,enabling effective separation from aqueous solutions by *** adsorption studies revealed that MO adsorption onto MAC followed pseudo-second-order kinetic and Freundlich isotherm model,with a maximum adsorption capacity of 205 mg/g at 25℃.Thermodynamic analysis showed that the adsorption process was spontaneous and *** degradation of MO and in-situ regeneration of MAC were achieved via Fenton-like reaction using sodium persulfate(PS).Under a PS concentration of 9 mmol/L,the MO removal efficiency near 95%after 60 min,with a total organic carbon(TOC)reduction of 83.1%.The reaction of Fe_(3)O_(4) and oxygen functional groups on AC surface with PS facilitated the generation of SO_(4)^(·-),thereby enhancing catalytic degradation of *** degradation efficiency improved as the temperature increased from 25℃ to 45℃.Cycle tests demonstrated that the MO removal efficiency of MAC remained above 90%after 5 cycles of ***,this study highlights the potential of MAC for efficient removal of organic dyes from water through the coupling of adsorption and Fenton-like degradation,providing a promising solution for addressing water pollution challenges.

关键词： Magnetic activated carbon Methyl orange Adsorption Sodium persulfate Fenton-like degradation

Epidemiological Characteristics of Visceral Leishmaniasis—Shanxi Province,China,1950–2019

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China CDC weekly 2022年第28期4卷 614-617,I0004页

作者： Yingze Zhao Ping Tie Yongfei Bai Liping Wang yuhua zheng Jiaojiao Zhang Xiao Qi Canjun zheng Xiao-nong Zhou National Institute for Viral Disease Control and Prevention Chinese Center for Disease Control and PreventionBeijingChina Shanxi Provincial Center for Disease Control and Prevention Taiyuan CityShanxi ProvinceChina Chinese Center for Disease Control and Prevention BeijingChina Beijing Center for Disease Control and Prevention BeijingChina National Institute of Parasitic Diseases of Chinese Center for Disease Control and Prevention ShanghaiChina.

Summary What is already known about this topic?Visceral leishmaniasis(VL)is the most serious form of *** recent years,reported cases of VL have been gradually increasing in Shanxi Province,*** is added by this report?The report describes the epidemiology of VL from 1950 to 2019 in Shanxi Province and the recent trend of VL *** are the implications for public health practice?Measures to prevent and control VL,such as health education,improving clinical diagnostics,strengthening epidemiological investigation capacity for VL cases,monitoring surveillance,and use of other evidence-based preventive measures,should be undertaken in Shanxi Province.

关键词： Shanxi strengthening education

Targeting self-enhanced ROS-responsive artesunatum prodrug nanoassembly potentiates gemcitabine activity by down-regulating CDA expression in cervical cancer

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Chinese Chemical Letters 2023年第7期34卷 186-192页

作者： Shengtao Wang Kunyi Yu Zhiyu Yu Bingchen Zhang Chaojie Chen Ling Lin Zibo Li Zhongjun Li yuhua zheng Zhiqiang Yu Affiliated Foshan Maternity&Child Healthcare Hospital Southern Medical University(Foshan Maternity&Child Healthcare Hospital)Foshan 528000China School of Pharmaceutical Sciences Southern Medical UniversityGuangzhou 510515China Department of Obstetrics and Gynecology Affiliated Dongguan HospitalSouthern Medical UniversityDongguan 523059China

Prodrug self-delivery carriers with targeting that specifically responded to tumor microenvironments have good potential to improve the application dilemma of approved clinical therapeutic drugs(systemic distribution and side effects).It's noted the conversion of gemcitabine(GEM)to inactive ingredients under the action of cytidine deaminase(CDA)during metabolism in vivo limits its clinical effect.A high level of reactive oxygen species(ROS)results in a high level of oxidative stress in tumor cells,which changes the expression of CDA and optimizes the metabolism of GEM in vivo and overcome drug *** this study,the ROS responsive and ROS self-supplied prodrug of artemisia(ART)-thioacetal bond(TK)-GEM was synthesized and self-vectors based on ART-TK-GEM(TK@FA NPs)was prepared by using nano *** responsive characteristics ensure specific release of prodrugs in tumor cells with high level of ROS thereby reducing side effects on normal cells and *** endogenous ROS and newly generated ROS by ART can reduce the expression of CDA and optimizes the metabolism of GEM,and the accumulated ROS can also induce apoptosis of tumor cells,realizing synergistic anti-tumor effect of chemical drugs and traditional Chinese *** paper proposes a simple method by using clinically approved drugs to improve the insufficient effect of existing chemotherapy and overcome resistance,which has potential to appropriately shorten the drug development cycle and accelerate the clinical investigation of drugs.

关键词： ROS self-supplied ROS-responsive Self-delivery carrier Down regulation of CDA Synergistic anti-tumor effect Cervical cancer

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基于GPS的提取操作模型及其应用规范研究

机械强度 2007年第4期29卷 632-636页

作者：张琳娜郑玉花郑鹏郑州大学机械工程学院郑州450001

揭示现代产品几何技术规范(geometrical product specification,GPS)中基于提取方案和提取点数的提取操作模型的构成规律;通过分析提取操作与产品功能特征、结构形状特征以及轮廓谐波成分之间的内在规律,给出面向产品几何特征的数字化... 详细信息

揭示现代产品几何技术规范(geometrical product specification,GPS)中基于提取方案和提取点数的提取操作模型的构成规律;通过分析提取操作与产品功能特征、结构形状特征以及轮廓谐波成分之间的内在规律,给出面向产品几何特征的数字化设计和计量的基础提取规范;并运用实例阐述该规范在工程实践中的实现方法,明确提取规范对于实现产品数字化规范设计与计量、丰富并完善ISO及我国现行GPS标准体系是至关重要的。

关键词：现代产品几何技术规范(geometrical product specification,GPS)提取提取规范恒定类

油气产业氢能利用的经济性与CO_(2)减排效益分析

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天然气工业 2023年第8期43卷 146-155页

作者：郑玉华张潇魏昭中国石油大学(北京)经济管理学院中国石油规划总院

中国在实现“双碳”目标和新型能源体系的构建过程中,油气产业发展中氢能利用具备独特的地域、技术和基础设施等优势。为此,总结了氢能产业的技术特点和油气产业发展氢能的优势,提出了4种典型的油气产业氢能发展路径,并运用蒙特卡罗模... 详细信息

中国在实现“双碳”目标和新型能源体系的构建过程中,油气产业发展中氢能利用具备独特的地域、技术和基础设施等优势。为此,总结了氢能产业的技术特点和油气产业发展氢能的优势,提出了4种典型的油气产业氢能发展路径,并运用蒙特卡罗模拟方法,从平准化成本和CO_(2)减排效益2个方面分析了各路径在不同资源禀赋条件下的发展趋势。研究结果表明:(1)蓝氢路径中,煤制氢耦合碳捕获与封存技术可以凭借其成本和CO_(2)减排优势作为油气产业氢气清洁化生产的过渡路径;绿氢路径的CO_(2)减排效益优于蓝氢路径,可以作为中长期的发展路径。(2)在天然气资源丰富、价格低于1.38元/m3的地区,天然气制氢耦合CCS技术具有较好的经济性和CO_(2)减排效果。(3)年光照有效发电小时数大于1390 h的油气田布局光伏制氢向加氢站供应清洁氢气将具有一定的经济可行性。(4)2030年,油气产业布局海上漂浮式风电制氢+天然气掺氢混合使用的业务在风力条件优越、年有效发电小时数大于2900 h的资源区将具备可行性。(5)其他资源区氢能利用路径的经济性则依赖于技术进步速度、碳市场价格和政策补贴力度。结论认为,氢能可以担当化石能源和可再生能源之间的桥梁作用,有助于持续推动能源体系向深度脱碳化发展。

关键词：氢能油气产业技术经济分析 CO_(2)减排 CCS

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变速磨削抑振的试验分析

系统工程理论与实践 1999年第6期19卷 137-140页

作者：郑玉华吉林工业大学机械学院

通过在磨削外圆中，使砂轮或工件的转速按一定规律变化的试验分析表明，砂轮或工件变速都有抑制颤振的作用，其原因是变速改变了砂轮和工件间的瞬时速比，使径向磨削力均值下降，减小了砂轮和工件间的接触刚度。

关键词：颤振变速磨削接触刚度试验砂轮

京津冀地区城市客运交通碳减排政策的成本效益分析

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资源科学 2022年第9期44卷 1772-1784页

作者：郑玉华贾艺伟中国石油大学(北京)经济管理学院北京102249 山东电力工程咨询院有限公司济南250013

客运交通在京津冀地区城市交通总量中占比高,其减排潜力是影响交通碳达峰的关键因素。本文建立了基于Agent建模与仿真方法的京津冀地区城市客运交通系统的模型,模拟了京津冀地区不同城市客运交通碳减排政策情景下消费者的交通出行行为,... 详细信息

客运交通在京津冀地区城市交通总量中占比高,其减排潜力是影响交通碳达峰的关键因素。本文建立了基于Agent建模与仿真方法的京津冀地区城市客运交通系统的模型,模拟了京津冀地区不同城市客运交通碳减排政策情景下消费者的交通出行行为,评估了各类碳减排政策的环境效益、经济成本及其对碳达峰的影响。结果显示:(1)乘用车燃料效能提升政策是唯一可以在2030年京津冀三地同时实现城市客运交通碳排放达峰的政策情景,且其碳减排的经济成本较低,其中天津市预计最先实现碳排放达峰,北京市次之,河北省最后;(2)公共交通推广政策的碳减排经济成本相对较高,尤其以河北省最为突出,虽然该政策可以在北京市和河北省实现城市客运交通碳排放达峰,但无法实现天津市碳排放达峰目标;(3)交通拥堵收费政策在京津冀三地单独实施无法实现碳排放达峰目标,需要与其他政策组合实施。基于此,京津冀三地实现客运交通碳排放达峰目标需要持续推进乘用车燃料效能的提升,此外还可以采取新能源汽车补贴、公共交通推广和交通拥堵收费等组合政策,以降低减排的经济成本。

关键词：城市交通碳减排成本效益自主体模拟交通碳排放情景分析京津冀地区

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CNC车床维修性及其特征量的统计与分析

系统工程理论与实践 1999年第8期19卷 133-139页

作者：郑玉华王义强吉林工业大学机械科学与工程系

根据本文所建数据库中数据对ＣＮＣ车床的维修性和有效度以及维修时间和停机时间的分布模型进行了统计与分析。

关键词：维修性维修时间停机时间分布模型数控车床

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油气勘探开发投资优化

石油勘探与开发 2009年第4期36卷 535-540页

作者：郑玉华罗东坤中国石油大学(北京)工商管理学院

以探明储量增长模型为基础建立了油气累计勘探投资与油气累计探明储量之间的关系模型;用数据包络分析法(DEA)建立了油气新建产能-油气开发工程建设投资模型。结合对数形式的油气开发操作成本模型构建了油公司油气开发投资-油气产量的关... 详细信息

以探明储量增长模型为基础建立了油气累计勘探投资与油气累计探明储量之间的关系模型;用数据包络分析法(DEA)建立了油气新建产能-油气开发工程建设投资模型。结合对数形式的油气开发操作成本模型构建了油公司油气开发投资-油气产量的关系模型;在投资-储量-产量关系模型的基础上,以企业利润最大化为目标,考虑产量构成、储采比及开采速度等方面的约束条件,构造了石油公司勘探开发投资多阶段优化模型,并用遗传算法给出了既定条件下石油公司多阶段最优化投资结构。该方法可以为石油公司制定长期发展战略规划、长期勘探开发投资方案提供方法依据,以减小勘探、开发投资中的盲目性及主观性,促进油气资源的合理、有序勘探开发。

关键词：勘探开发投资决策投资优化油气储量油气产量