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A micro-crosslinked amphoteric hydrophobic association copolymer as high temperature-and salt-resistance fluid loss reducer for water-based drilling fluids

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Petroleum Science 2024年第3期21卷 1980-1991页

作者： jian Li Yu-xi ji xiao-xiao Ni Kai-He Lv xian-Bin Huang jin-Sheng Sun School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongChina Key Laboratory of Unconventional Oil&Gas Development China University of Petroleum(East China)Qingdao26650ShandongChina Inspection and Testing Center of Huabei Oil Field Company PetroChinaRenqiu062552HebeiChina Drilling Fluid Research Institute CNPC Engineering Technology R&D Company LimitedBeijing102206China

During ultradeep oil and gas drilling,fluid loss reducers are highly important for water-based drilling fluids,while preparing high temperature-and salt-resistance fluid loss reducers with excellent rheology and filtration performance remains a ***,a micro-crosslinked amphoteric hydrophobic association copolymer(i.e.,DADC)was synthesized using N,N-dimethyl acrylamide,diallyl dimethyl ammonium chloride,2-acrylamido-2-methylpropane sulfonic acid,hydrophobic monomer,and pentaerythritol triallyl ether *** to the synergistic effects of hydrogen bonds,electrostatic interaction,hydrophobic association,and micro-crosslinking,the DADC copolymer exhibited outstanding temperature-and *** rheological experiments have shown that the DADC copolymer had excellent shear dilution performance and a certain degree of salt-responsive viscosity-increasing *** DADC copolymer could effectively adsorb on the surface of bentonite particles through electrostatic interaction and hydrogen bonds,which bring more negative charge to the bentonite,thus improving the hydration and dispersion of bentonite particles as well as the colloidal stability of the drilling ***,the drilling fluids constructed based on the DADC copolymer exhibited satisfactory rheological and filtration properties(FLHTHP=12 m L)after aging at high temperatures(up to200℃)and high salinity(saturated salt)***,this work provided new insights into designing and fabricating high-performance drilling fluid treatment agents,demonstrating good potential applications in deep and ultradeep drilling engineering.

关键词： Fluid loss reducer Temperature-and salt-resistance Hydrophobic association Amphoteric Micro-crosslinking

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Exploring the impact of pericentric inversion of chromosome 9 on fertility in sperm donors

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Asian Journal of Andrology 2024年第3期26卷 302-307页

作者： Qian Liu Wen-Jun Zhou Zeng-Hui Huang xiu-Hai Huang jian Wu xi-Ren ji Xue-Feng Luo Yu-Ling Tang Rui-Jun Wang Li-Qing Fan Chuan Huang Wen-Bing Zhu Institute of Reproductive and Stem Cell Engineering Basic Medicine CollegeCentral South UniversityChangsha 410013China Clinical Research Center for Reproduction and Genetics in Hunan Province Reproductive and Genetic Hospital of CITIC-XiangyaChangsha 410005China

Pericentric inversion of chromosome 9(inv[9])is a common chromosomal structural variant,but its impact on clinical outcomesremains *** screening criteria of sperm banks are rarely mentioned to individuals with inv(9).In this study,we evaluatedthe fertility of sperm donors with inv(9)who met eligibility criteria for sperm banks(inv[9]-eligible donors).From March 2004 toMay 2022,chromosomal analysis of 16124 sperm donors at CITIC-xiangya Human Sperm Bank in Hunan Province(Changsha,China)found that 251(1.6%)had chromosome variations,with inv(9)being the most prevalent at 1.1%.All 169 inv(9)-eligibledonors were contacted to collect fertility outcome data,along with 206 eligible donors without inv(9)as *** addition,semen samples from inv(9)-eligible donors and eligible donors underwent assessments of sperm fluorescence in situ hybridization(FISH),mitochondrial membrane potential,DNA fragmentation index,acrosome integrity,reactive oxygen species(ROS),andsperm *** showed that inv(9)did not significantly increase reproductive risks *** detecting ROSlevel differences,the clinical impact may be *** study provides new data on the inv(9)population that can serveas a valuable reference for decision-making by sperm banks as well as for genetic counseling and clinical guidance for individualscarrying inv(9)variant.

关键词： male fertility pericentric inversion of chromosome 9 sperm bank sperm functional parameters

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基于PLUS-InVEST模型的江西省生态系统碳储量时空演变与预测

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环境科学 2024年第6期45卷 3284-3296页

作者：胡佶熹勒先文王卫林熊媛谭雪兰湖南农业大学公共管理与法学学院长沙410128 萍乡学院商学院萍乡337000 湖南农业大学资源学院长沙410128 萍乡学院材料与化学工程学院萍乡337000

土地利用变化是影响陆地生态系统碳储量变化的重要因素,研究土地利用变化与碳储量之间关系对优化区域土地利用结构,维持区域碳平衡可提供可靠的数据支撑.以江西省为例,分析1990~2020年土地利用变化,基于PLUS模型,结合自然发展情景、生... 详细信息

土地利用变化是影响陆地生态系统碳储量变化的重要因素,研究土地利用变化与碳储量之间关系对优化区域土地利用结构,维持区域碳平衡可提供可靠的数据支撑.以江西省为例,分析1990~2020年土地利用变化,基于PLUS模型,结合自然发展情景、生态优先情景和经济发展情景设置,对2030年江西省土地利用格局进行模拟分析,运用In VEST模型测算1990~2020年及未来不同情景下江西省碳储量变化,利用空间自相关分析探索江西省不同情景下陆地生态系统碳储量时空变化特征,并提出相应的政策建议.结果表明:①1990~2020年江西省碳储量整体呈下降趋势,共减少4.58×10^(7)t.其中,水域和建设用地的面积增加,耕地、林地、草地及未利用地面积减少是导致碳储量减少的主要原因.②2030年江西省陆地生态系统碳储量在自然发展情景、生态优先情景和经济发展情景下分别为2.20×10^(9)、2.24×10^(9)和2.19×10^(9)t.③3种情景下的碳储量值在空间分布上具有相似性,碳储量高值区域在江西省北部、西北部及西部区域出现集聚,低值区域则在中部区域聚集.研究结果可为江西省未来国土空间规划,提升陆地生态系统碳储量提供数据支撑.

关键词：土地利用变化碳储量 InVEST模型 PLUS模型江西省

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红景天苷调控RAGE/JAK1/STAT3信号通路对糖尿病肾病小鼠的肾脏保护作用研究

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中国中药杂志 2024年第8期49卷 2188-2196页

作者：冷昌龙林款周梅叶贤胜舒细记柳威江汉大学武汉生物医学研究院湖北武汉430000

基于糖基化终末产物受体(receptor for advanced glycation end products,RAGE)/酪氨酸激酶1(janus activated kinase 1,JAK1)/信号转导和转录激活因子3(signal transduction and activator of transcription 3,STAT3)信号通路探讨红景天苷对糖尿病肾病(diabetic nephropathy,DN)小鼠肾损伤的保护作用。采用高糖高脂饮食联合腹腔注射链脲佐菌素(streptozotocin,STZ)建立小鼠DN模型,随机分为正常组、模型组、红景天苷低剂量(20 mg·kg~(-1))组、红景天苷高剂量(100 mg·kg~(-1))组、二甲双胍(140 mg·kg~(-1))组,每组12只。造模成功后每日灌胃相应药物或溶剂1次,持续10周,每2周测定体质量、日饮水量,检测空腹血糖(fasting blood glucose,FBG)。末次给药结束后,进行口服糖耐量测试,收集24 h尿液、血清及肾组织样本。采用生化法检测24 h尿蛋白(24 hours urinary total protein,24 h-UTP),血清肌酐(serum creatinine,Scr)、尿素氮(blood urea nitrogen,BUN)、甘油三酯(triglyceride,TG)、总胆固醇(total cholesterol,TC)、低密度脂蛋白胆固醇(low density lipoprotein cholesterol,LDL-C)、高密度脂蛋白胆固醇(high density lipoprotein cholesterol,HDL-C)水平;过碘酸雪夫(periodic acid-Schiff,PAS)染色观察肾组织病理形态变化;免疫组织化学染色检测肾脏α-平滑肌肌动蛋白(α-smooth muscle actin,α-SMA)、波形蛋白(vimentin)、糖基化终末产物(advanced glycation end products,AGEs)表达;试剂盒检测肾组织超氧化物歧化酶(superoxide dismutase,SOD)、过氧化氢酶(catalase,CAT)、谷胱甘肽过氧化物酶(glutathione peroxidase,GSH-PX)活力以及丙二醛(malondialdehyde,MDA)水平;酶联免疫吸附测定法(enzyme-linked immunosorbent assay,ELISA)检测血清AGEs、羧乙基赖氨酸(carboxyethyllysine,CEL)、羧甲基赖氨酸(carboxymethyllysine,CML)水平;蛋白免疫印迹法(Western blot)检测肾组织RAGE蛋白表达以及JAK1、STAT3蛋白的磷酸化水平。结果显示,与正常组比较,模型组小鼠FBG,血糖曲线下面积(area under the curve of glucose,AUCG),饮水量,肾脏指数,24 h-UTP,肾小管损伤评分,肾小球细胞外基质占比,血清中Scr、BUN、TG、LDL-C、AGEs、CEL、CML水平,肾组织中MDA含量,α-SMA、vimentin、AGEs、RAGE蛋白表达及JAK1、STAT3蛋白的磷酸化水平显著增加(P<0.01);血清HDL-C水平,肾组织SOD、CAT、GSH-PX活力显著降低(P<0.01)。与模型组比较,红景天苷高剂量组小鼠上述指标变化均显著逆转(P<0.05或P<0.01)。该研究表明,红景天苷可通过抑制AGEs介导的RAGE/JAK1/STAT3信号轴活性减轻氧化应激反应和肾脏纤维化,发挥治疗DN的作用。

关键词：红景天苷糖尿病肾病氧化应激肾脏纤维化 RAGE/JAK1/STAT信号轴

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Alternative industrial carbon emissions benchmark based on input-output analysis

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Frontiers of Earth Science 2016年第4期10卷 731-739页

作者： Mengyao HAN xi ji Institute of Geographic Sciences and Natural Resources Research Chineses Academy of Sciences Beijing 100871 China College of Engineering Peking University Beijing 100871 China School of Economics Peking University Beijing 100871 China

Some problems exist in the current carbon emissions benchmark setting systems. The primary con- sideration for industrial carbon emissions standards highly relate to direct carbon emissions （power-related emissions） and only a portion of indirect emissions are considered in the current carbon emissions accounting processes. This practice is insufficient and may cause double counting to some extent due to mixed emission sources. To better integrate and quantify direct and indirect carbon emissions, an embodied industrial carbon emissions benchmark setting method is proposed to guide the establishment of carbon emissions benchmarks based on input-output analysis. This method attempts to link direct carbon emissions with inter-industrial economic exchanges and systematically quantifies carbon emissions embodied in total product delivery chains. The purpose of this study is to design a practical new set of embodied intensity-based benchmarks for both direct and indirect carbon emissions. Beijing, at the first level of carbon emissions trading pilot schemes in China, plays a significant role in the establish- ment of these schemes and is chosen as an example in this study. The newly proposed method tends to relate emissions directly to each responsibility in a practical way through the measurement of complex production and supply chains and reduce carbon emissions from their original sources. This method is expected to be developed under uncertain internal and external contexts and is further expected to be generalized to guide the establish- ment of industrial benchmarks for carbon emissions trading schemes in China and other countries.

关键词： emissions trading scheme benchmarking,carbon emissions input-output analysis

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Scalable peer-to-peer resource discovering scheme for wireless self-organized networks

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The Journal of China Universities of Posts and Telecommunications 2009年第2期16卷 47-52,57页

作者： LI xi ji Hong Key Laboratory of Universal Wireless Communications Minisa-y of Education Beijing University of Posts and Telecommunications Beijing 100876 China

Peer-to-peer technologies have attracted increasing research attention with fruitful protocols and applications proposed for wired networks. As to mobile environments, there are currently no mature deployments. A novel resource managing and discovering protocol, Cheer, is proposed to realize scalable and effective peer-to-peer lookup in wireless self-organized networks. Cheer resolves the topologies mismatch problem between peer-to-peer overlay networks and actual nodes distribution, allowing for frequent nodes membership changes. With specially designed resource storage table, Cheer also supports multikey and fuzzy lookup. Its hybrid architecture and improved routing scheme based on small-world theory may realize effective lookup routing. Theoretical analysis and simulation results both prove that Cheer makes using peer-to-peer applications in large-scale self-organized mobile networks feasible and promising.

关键词： peer-to-peer small-world resource discovering

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Embodied energy consumption and carbon emissions evaluation for urban industrial structure optimization

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Frontiers of Earth Science 2014年第1期8卷 32-43页

作者： xi ji Zhanming CHEN jinkai LI School of Economics Peking University Beijing 100871 China Department of Energy Economics School of Economics Renmin University of China Beijing 100872 China Guanghua School of Management Peking University Beijing 100871 China

Cities are the main material processors asso- ciated with industrialization. The development of urban production based on fossil fuels is the major contributor to the rise of greenhouse gas density, and to global warming. The concept of urban industrial structure optimization is considered to be a solution to urban sustainable develop- ment and global climate issues. Enforcing energy con- servation and reducing carbon emissions are playing key roles in addressing these issues. As such, quantitative accounting and the evaluation of energy consumption and corresponding carbon emissions, which are by-products of urban production, are critical, in order to discover potential opportunities to save energy and to reduce emissions. Conventional evaluation indicators, such as ＂energy consumption per unit output value＂ and ＂emissions per unit output value＂, are concerned with immediate consumptions and emissions; while the indirect consump- tions and emissions that occur throughout the supply chain are ignored. This does not support the optimization of the overall urban industrial system. To present a systematic evaluation framework for cities, this study constructs new evaluation indicators, based on the concepts of ＂embodied energy＂ and ＂embodied carbon emissions＂, which take both the immediate and indirect effects of energy consumption and emissions into account. Taking Beijing as a case, conventional evaluation indicators are compared with the newly constructed ones. Results show that the energy consumption and emissions of urban industries are represented better by the new indicators than by conventional indicators, and provide useful information for urban industrial structure optimization.

关键词： embodied carbon emissions embodied energy industrial structure optimization urban economy

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Regional study on investment for transmission infrastructure in China based on the State Grid data

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Frontiers of Earth Science 2017年第1期11卷 162-183页

作者： Wendong WEI Xudong WU xiaofang WU Qiangmin xi xi ji Guoping LI College of Government Peking University Beijing 100871 China College of Engineering Peking University Beijing 100871 China School of Economics Nankai University Tianjin 300071 China School of Economics Peking University Beijing 100871 China

Transmission infrastructure is an integral component of safeguarding the stability of electricity delivery. However, existing studies of transmission infra- structure mostly rely on a simple review of the network, while the analysis of investments remains rudimentary. This study conducted the first regionally focused analysis of investments in transmission infrastructure in China to help optimize its structure and reduce investment costs. Using State Grid data, the investment costs, under various voltages, for transmission lines and transformer substa- tions are calculated. By analyzing the regional profile of cumulative investment in transmission infrastructure, we assess correlations between investment, population, and economic development across the regions. The recent development of ultra-high-voltage transmission networks will provide policy-makers new options for policy development.

关键词： regional study energy geography investment analysis transmission lines transformer substation

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基于PLC控制的间歇移动烟苗移栽机控制系统设计与实现

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现代机械 2024年第3期 77-81页

作者：王海涛吉嶲杨伟贵州轻工职业技术学院贵州贵阳550025 贵州大学机械工程学院贵州贵阳550025

为了提高烟苗移栽的适应性和通用性,设计了一种以蓄电池为动力源、以履带为行走机构、采用导苗管投苗的间歇移动式烟苗移栽机。以烟苗移栽农艺为基础设计移栽机系统,使用SolidWorks软件进行套装设计和三维模型绘制,使用PLC和触摸屏进行... 详细信息

为了提高烟苗移栽的适应性和通用性,设计了一种以蓄电池为动力源、以履带为行走机构、采用导苗管投苗的间歇移动式烟苗移栽机。以烟苗移栽农艺为基础设计移栽机系统,使用SolidWorks软件进行套装设计和三维模型绘制,使用PLC和触摸屏进行控制程序设计和编写。试验结果表明:移栽机性能满足烟苗移栽农艺要求,能够很好进行特殊山地作业,能周期性的完成钻孔—投苗—施肥的移栽流程,提高了栽植效率,并可以通过改变触摸屏数据和PLC程序来修改移栽机作业流程,为后续相关研究提供参考。

关键词：移栽机烟苗移栽 PLC 触摸屏 SolidWorks

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断层倾角对冲击地压危险性影响研究

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能源与节能 2024年第2期 199-203页

作者：许磊吉锡马治国玛纳斯县矿山安全服务保障中心新疆昌吉832200 玛纳斯县天欣煤业有限公司新疆昌吉832200

采用FLAC3D数值模拟软件,以接触面单元模拟断层上下盘构造关系,模拟在断层地质构造下,工作面从断层下盘向断层面推进过程中,在不同断层倾角和落差下的矿山压力分布规律和断层带位移变化规律。结果表明,在正断层地质构造下,以下盘工作面... 详细信息

采用FLAC3D数值模拟软件,以接触面单元模拟断层上下盘构造关系,模拟在断层地质构造下,工作面从断层下盘向断层面推进过程中,在不同断层倾角和落差下的矿山压力分布规律和断层带位移变化规律。结果表明,在正断层地质构造下,以下盘工作面开采为研究对象,距断层距离40 m处,断层倾角小于70°时,诱发冲击地压的危险性较大,当断层倾角大于70°时,冲击地压危险性有所降低。

关键词：正断层倾角数值模拟冲击地压

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