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Study of the pressure transient behavior of directional wells considering the effect of non-uniform flux distribution

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Petroleum Science 2024年第3期21卷 1765-1779页

作者： Yan-Zhong Liang Bai-Lu Teng wan-jing Luo School of Energy Resources China University of Geosciences(Beijing)Beijing100083China

During the production,the fluid in the vicinity of the directional well enters the wellbore with different rates,leading to non-uniform flux distribution along the directional ***,in all existing studies,it is oversimplified to a uniform flux distribution,which can result in inaccurate results for field ***,this paper proposes a semi-analytical model of a directional well based on the assumption of non-uniform flux ***,the direction well is discretized into a carefully chosen series of linear sources,such that the complex well trajectory can be captured and the nonuniform flux distribution along the wellbore can be considered to model the three-dimensional flow *** using the finite difference method,we can obtain the numerical solutions of the transient flow within the *** the aid of Green's function method,we can obtain the analytical solutions of the transient flow from the matrix to the *** complete flow behavior of a directional well is perfectly represented by coupling the above two types of transient ***,on the basis of the proposed model,we conduct a comprehensive analysis of the pressure transient behavior of a directional *** computation results show that the flux variation along the direction well has a significant effect on pressure *** addition,the directional well in an infinite reservoir may exhibit the following flow regimes:wellbore afterflow,transition flow,inclined radial flow,elliptical flow,horizontal linear flow,and horizontal radial *** horizontal linear flow can be observed only if the formation thickness is much smaller than the well ***,a dip region that appears on the pressure derivative curve indicates the three-dimensional flow behavior near the wellbore.

关键词： Directional well Pressure transient behavior Semi-analytical model Non-uniform flux

Investigation of Maxima Assumptions in Modelling Tropical Cyclone- Induced Hazards in the South China Sea

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China Ocean Engineering 2024年第3期38卷 491-504页

作者： WEN Ze-guo wanG Fu-ming wan jing YANG Fan School of Civil Engineering Sun Yat-sen University&Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082China Guangdong Academy of Safety Science and Technology Guangzhou 510060China Guangdong Key Laboratory of Oceanic Civil Engineering Guangzhou 510275China Advanced Energy Science and Technology Guangdong Laboratory(Yangjiang Offshore Wind Energy Laboratory) Yangjiang 529500China

The present study aims to examine the suitability of two commonly used assumptions that simplify modelling metoceanconditions for designing offshore wind turbines in the South China Sea (SCS). The first assumption assumes thatjoint N-year extreme wind and wave events can be independently estimated and subsequently combined. The secondone assumes peak wind and waves can be modelled as occurring simultaneously during a tropical cyclone (TC) *** better understand the potential TC activity, a set of 10000 years synthetic TC events are generated. The wind fieldmodel and the Mike 21 spectral wave model are employed to model the TC-induced hazards. Subsequently, theeffect of the assumptions is evaluated by analyzing the peak structural response of both monopile and semisubmersibleoffshore wind turbines during TC events. The results demonstrate that the examined assumptions are generally *** assessing the implications of these assumptions, valuable insights are obtained, which can inform andimprove the modelling of TC-induced hazards in the SCS region.

关键词： tropical cyclone numerical wave modelling hazards offshore wind turbines structural response

Alkali Tolerance of Concrete Internal Curing Agent Based on Sodium Carboxymethyl Starch

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 82-90页

作者：陈梅花刘荣进 CHEN Ping jing Daiyan wan Dandan FU Siyuan College of Materials Science and Engineering Guilin University of TechnologyGuilin 541004China Guangxi Engineering and Technology Center for Utilization of Industrial Waste Residue in Building Materials Guilin 541004China Guangxi Maibu New Material Limited Company Guilin 541004China

Internal curing agents (ICA) based on super absorbent polymer have poor alkali tolerance and reduce the early strength of *** alkali tolerate internal curing agent (CAA-ICA) was designed and prepared by using sodium carboxymethyl starch (CMS) with high hydrophilicity,acrylic acid (AA) containing anionic carboxylic group and acrylamide (AM) containing non-ionic amide group as the main raw *** results show that the ratio of CAA-ICA alkali absorption solution is higher than that existing ICA,which solves the low water absorption ratio of the ICA in alkali *** water absorption ratio of CAA-ICA in saturated Ca(OH)_(2) solution is 95.8 g·g^(-1),and the alkali tolerance coefficient is *** application of CAA-ICA in cement-based materials can increase the internal relative humidity and miniaturize the pore *** compressive strength of mortar increases up to 12.95%at 28 d,which provids a solution to overcome the reduction of the early strength.

关键词： alkali tolerance sodium carboxymethyl starch internal curing agent compressive strength

Adverse effect of niobium and boron on hot deformation behavior of sulfur-containing steel

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Journal of Iron and Steel Research International 2024年第1期31卷 252-263页

作者： Guo-ning He Shi-qi wan Bo Jiang Chao-lei Zhang Ya-zheng Liu Chun-jing Wu School of Materials Science and Engineering University of Science and Technology BeijingBeijing100083China Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing100083China

The hot deformation behaviors of sulfur-containing gear steel 20MnCr5 containing three different contents of Nb and B(0,0.021%Nb,and 0.024%Nb-0.0022%B)were *** compression and tenssion tests were carried out by Gleeble3800 at the austenite region from 850 to 1150℃and the adverse effects of Nb and B were analyzed by the fracture,microstructure and precipitate *** compression tests showed that the proportions of instable area in hot processing maps of 0.021%Nb and Nb-B steels were higher and the deformability of Nb free steel was *** tensile deformation experiments showed that the reduction areas of Nb free,0.021%Nb and Nb-B steels were 92%-99%,84%-98%and 67%-97%,*** addition of Nb or Nb and B inhibited the dynamic recrystallization during hot deformation,and consequently,more deformed grains were then formed in 0.021%Nb and Nb-B steels thus to obtain the microstructure with worse uniformity and then deteriorate the *** addition,the interaction between inclusions and microalloyed elements was also *** particles of 0.021%Nb and Nb-B steels dynamically precipitated during deformation and precipitated together with MnS thus to worsen the deformability,resulting in the decrease of reduction area.

关键词： Hot deformation Gear steel Processing map Dynamic recrystallization Microalloying

Mental retardation,seizures and language delay caused by new SETD1B mutations:Three case reports

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World Journal of Clinical Cases 2024年第2期12卷 383-391页

作者： Le Ding Li-wan Wei Tai-Song Li jing Chen Department of Neurology Children’s Hospital of Nanjing Medical UniversityNanjing 210000Jiangsu ProvinceChina Chigene(Beijing)Translational Medical Research Center Co.Ltd.Beijing 101111China

BACKGROUND The SETD1B gene is instrumental in human intelligence and nerve *** in the SETD1B gene have been linked in recent studies to neurodevelopmental disorders,seizures,and language *** SUMMARY This study aimed to analyze the clinical manifestations and treatment of three patients suffering from mental retardation,epilepsy,and language delay resulting from a new mutation in the SETD1B *** individuals with these symptoms were selected,and their clinical symptoms,gene test results,and treatment were *** article discusses the impact of the SETD1B gene mutation on patients and outlines the treatment *** the three patients(two females and one male,aged 8,4,and 1,respectively),all exhibited psychomotor retardation,attention deficit,and hyperactivity disorder,and two had *** treatment with sodium tripolyvalproate halted the seizures in the affected child,although mental development remained somewhat *** exome sequencing revealed new mutations in the SETD1B gene for all patients,specifically with c.5473C>T(***1825trp),c.4120C>T(***1374*,593),c.14_15insC(***5Hisfs*33).CONCLUSION Possessing the SETD1B gene mutation may cause mental retardation accompanied by seizures and language *** the exact mechanism is not fully understood,interventions such as drug therapy,rehabilitation training,and family support can assist patients in managing their symptoms and enhancing their quality of ***,genetic testing supplies healthcare providers with more precise diagnostic and therapeutic guidance,informs families about genetic disease risks,and contributes to understanding disease pathogenesis and drug research and development.

关键词： Neurodevelopmental disorder Seizure SETD1B gene Whole-exome sequencing New mutation Case report

Economic policy uncertainty and firms’investments in venture capital funds:Evidence from China

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China Journal of Accounting Research 2024年第4期17卷 190-206页

作者： Liangyong wan Xin Sui jing Rao Lai Deng School of Business Administration South China University of TechnologyGuangzhouChina School of Management Guangdong University of TechnologyGuangzhouChina

The latest business practice in the Chinese venture capital(VC)market involves the active participation of non-financial firms,as limited partners,in VC *** a unique hand-collected dataset from China,we find that economic policy uncertainty is positively related to the propensity of firms to participate in VC ***-sectional tests show that the positive effect of policy uncertainty on the likelihood of participating in VC funds is enhanced by industrial growth ***,economic consequence tests show that participating in VC funds is conducive to improving investment efficiency,increasing innovation performance and promoting product diversifica*** study advances our understanding of firms’investment decisions and the VC industry development amid economic policy uncertainty.

关键词： Economic policy uncertainty Venture capital Investment decision Limited partner

The NAC transcription factor LuNAC61 negatively regulates fiber development in flax (Linum usitatissimum L.)

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Journal of Integrative Agriculture 2024年第3期23卷 795-805页

作者： Dongwei Xie jing Li wan Li Lijun Sun Zhigang Dai Wenzhi Zhou Jianguang Su Jian Sun School of Life Sciences Nantong UniversityNantong 226019China Institute of Crop Cultivation and Tillage Heilongjiang Academy of Agricultural SciencesHarbin 150086China Institute of Bast Fiber Crops Chinese Academy of Agricultural SciencesChangsha 410221China Jiangsu Sanshu Biotechnology Co.Ltd. Nantong 226001China

Flax is a crucial fiber crop that exhibits excellent textile properties and serves as a model plant for investigating phloem fiber development. The regulation of multiple genes significantly influences fiber development, notably involving NAC(NAM, ATAF1/2, CUC2) transcription factors in forming the fiber secondary cell wall(SCW).Overexpression of LuNAC61 in flax resulted in sparse top meristematic zone leaves and significantly reduced stem cellulose content. Scanning electron microscopy and staining observations revealed a significant reduction in fiber bundles. β-Glucuronidase(GUS) staining analysis demonstrated high activity of the LuNAC61 promoter in the bast fibers of the flax stem. Additionally, several members of the LuPLATZ and LuCesA families exhibited significant coexpression with LuNAC61. Subcellular localization indicated the presence of LuPLATZ24 protein in the nucleus and cytoplasm, LuNAC61 protein exclusively in the nucleus, and LuCesA10 in the nucleus and endoplasmic reticulum. LuPLATZ24 positively regulates LuNAC61, whereas LuNAC61 negatively affects LuCesA10, suggesting the involvement of a metabolic network in regulating flax fiber development. In conclusion, this study provides a critical opportunity for a comprehensive and in-depth analysis of the mechanisms governing flax fiber development and the potential use of biotechnology to enhance flax fiber yield.

关键词： flax fiber development Lu NAC61 gene function gene interaction

Effect of bubble morphology and behavior on power consumption in non-Newtonian fluids’aeration process

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Chinese Journal of Chemical Engineering 2024年第1期65卷 243-254页

作者： Xiemin Liu jing wan Jinnan Sun Lin Zhang Feng Zhang Zhibing Zhang Xinyao Li Zheng Zhou Key Laboratory of Mesoscopic Chemistry of Ministry of Education(MOE) School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China Dalian Research Institute of Petroleum and Petrochemicals SINOPECDalian 116045China

Due to a prolonged operation time and low mass transfer efficiency, the primary challenge in the aeration process of non-Newtonian fluids is the high energy consumption, which is closely related to the form and rate of impeller, ventilation, rheological properties and bubble morphology in the reactor. In this perspective, through optimal computational fluid dynamics models and experiments, the relationship between power consumption, volumetric mass transfer rate(kLa) and initial bubble size(d0) was constructed to establish an efficient operation mode for the aeration process of non-Newtonian fluids. It was found that reducing the d0could significantly increase the oxygen mass transfer rate, resulting in an obvious decrease in the ventilation volume and impeller speed. When d0was regulated within 2-5 mm,an optimal kLa could be achieved, and 21% of power consumption could be saved, compared to the case of bubbles with a diameter of 10 mm.

关键词： Non-Newtonian fluids aeration process Power consumption Volumetric mass transfer rate Bubble size

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出口车道左转交叉口几何及信号组合优化模型

中国公路学报 2017年第2期30卷 120-127页

作者：赵靖马万经韩印上海理工大学交通系统工程系上海200093 同济大学交通运输工程学院上海200092

为了进一步提高出口车道左转这种非常规交叉口的运行水平,提出了一种基于组合设计的优化方法。优化模型以储备通行能力最大作为优化目标,考虑交通流量、车道功能划分、主信号控制、预信号控制、综合功能区长度以及饱和度等约束条件,描... 详细信息

为了进一步提高出口车道左转这种非常规交叉口的运行水平,提出了一种基于组合设计的优化方法。优化模型以储备通行能力最大作为优化目标,考虑交通流量、车道功能划分、主信号控制、预信号控制、综合功能区长度以及饱和度等约束条件,描述了优化参数间的相互关系,建立了混合整数非线性规划模型。该模型将交叉口几何布置与信号控制的关键参数整合在一个统一的优化框架中,以保障设计结果最优。通过将模型转化为一系列混合整数线性规划,采用分支定界法对其进行求解,进而通过算例和敏感性分析验证出口车道左转交叉口的优化效益。研究结果表明:利用出口车道左转的设计方法不仅可在饱和度较大的情况下显著提升交叉口通行能力,使原本处于过饱和状态的交叉口变为不饱和;而且在低流量水平下,也有助于减少交叉口延误和排队长度,算例中分别降低1.2%和5.1%;并且优化效益随左转交通量比例以及使用该设计方法岔口数的增加而增加,左转交通量比例每增加5%,该设计方法计算的通行能力将增加1%~5%,平均每增加1个岔口的使用,可使交叉口通行能力提高6.1%。

关键词：交通工程非常规交叉口非线性规划出口车道左转组合优化