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Development and performance evaluation of high temperature resistant strong adsorption rigid blocking agent

Petroleum Science 2024年第4期21卷 2650-2662页

作者： Zhe Xu Jin-Sheng Sun Jing-Ping Liu Kai-He Lv xiao-dong dong Zong-Lun Wang Tai-Feng Zhang Yuan-Wei Sun Zhi-Wen Dai School of Petroleum Engineering China University of Petroleum (East China) CNPC Engineering Technology R&D Company Limited

As drilling wells continue to move into deep ultra-deep layers, the requirements for temperature resistance of drilling fluid treatments are getting higher and higher. Among them, blocking agent, as one of the key treatment agents, has also become a hot spot of research. In this study, a high temperature resistant strong adsorption rigid blocking agent(QW-1) was prepared using KH570 modified silica,acrylamide(AM) and allyltrimethylammonium chloride(TMAAC). QW-1 has good thermal stability,average particle size of 1.46 μm, water contact angle of 10.5., has a strong hydrophilicity, can be well dispersed in water. The experimental results showed that when 2 wt% QW-1 was added to recipe A(4 wt% bentonite slurry+0.5 wt% DSP-1(filtration loss depressant)), the API filtration loss decreased from 7.8to 6.4 m L. After aging at 240.C, the API loss of filtration was reduced from 21 to 14 m L, which has certain performance of high temperature loss of filtration. At the same time, it is effective in sealing 80-100mesh and 100-120 mesh sand beds as well as 3 and 5 μm ceramic sand discs. Under the same conditions,the blocking performance was superior to silica(5 μm) and calcium carbonate(2.6 μm). In addition, the mechanism of action of QW-1 was further investigated. The results show that QW-1 with amide and quaternary ammonium groups on the molecular chain can be adsorbed onto the surface of clay particles through hydrogen bonding and electrostatic interaction to form a dense blocking layer, thus preventing further intrusion of drilling fluid into the formation.

关键词： High adsorption Rigid microsphere High temperature resistance Blocking performance

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基于ND5序列的西北太平洋海域四种弹涂鱼遗传变异比较研究

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海洋与湖沼 2024年第4期55卷 1037-1047页

作者：肖东东吴增满赵林林宋娜中国海洋大学海水养殖教育部重点实验室山东青岛266003 自然资源部第一海洋研究所山东青岛266061

弹涂鱼是一类两栖性鱼类的统称,具有重要的经济价值和生态价值。本研究基于线粒体ND5基因序列比较分析了西北太平洋地区4种弹涂鱼,即弹涂鱼(Periophthalmus modestus)、大鳍弹涂鱼(Periophthalmus magnuspinnatus)、大弹涂鱼(Boleophtha... 详细信息

弹涂鱼是一类两栖性鱼类的统称,具有重要的经济价值和生态价值。本研究基于线粒体ND5基因序列比较分析了西北太平洋地区4种弹涂鱼,即弹涂鱼(Periophthalmus modestus)、大鳍弹涂鱼(Periophthalmus magnuspinnatus)、大弹涂鱼(Boleophthalmus pectinirostris)和薄氏大弹涂鱼(Boleophthalmus boddarti)的群体遗传多样性和遗传结构。研究结果显示,在长度549 bp的线粒体ND5序列中,单倍型多样度:弹涂鱼>薄氏大弹涂鱼>大弹涂鱼>大鳍弹涂鱼,核苷酸多样度:大弹涂鱼>弹涂鱼>薄氏大弹涂鱼>大鳍弹涂鱼。此外,基于单倍型序列构建的邻接关系树可以看出,4种弹涂鱼的单倍型可各自聚成单系,但种内均不存在显著的谱系结构。群体间的遗传分化指数(Fst)表明弹涂鱼的中日群体间存在显著分化,大弹涂鱼湛江、厦门、温州群体两两之间遗传分化与其地理距离呈正比。分子方差分析(AMOVA)的结果显示分子变异主要来自于群体内,表明其群体内多样性较高。中性检验、核苷酸不配对分布以及贝叶斯天际线分析结果均表明弹涂鱼和大弹涂鱼在更新世末期可能经历了群体扩张事件。该研究对西北太平洋海域的4种弹涂鱼的遗传变异进行了全面的比较分析,研究结果可为弹涂鱼鱼类的资源保护与合理利用提供基础资料。

关键词：西北太平洋 4种弹涂鱼类遗传多样性遗传结构

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改进型LCL并网逆变器电容电流正反馈控制策略

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太原科技大学学报 2024年第3期45卷 278-284,291页

作者：董晓冬乔建华太原科技大学电子信息工程学院太原030024

弱电网下LCL滤波并网逆变器采用传统电容电流比例有源阻尼进行入网控制时,阻尼环等效为并联在电容两端的虚拟阻抗Z_(eq)(s),而Z_(eq)(s)的负阻特性易导致控制系统无法适应较宽范围内变化的电网阻抗,鲁棒性较差甚至失稳。鉴于此,提出一... 详细信息

弱电网下LCL滤波并网逆变器采用传统电容电流比例有源阻尼进行入网控制时,阻尼环等效为并联在电容两端的虚拟阻抗Z_(eq)(s),而Z_(eq)(s)的负阻特性易导致控制系统无法适应较宽范围内变化的电网阻抗,鲁棒性较差甚至失稳。鉴于此,提出一种改进型电容电流有源阻尼正反馈控制策略,通过在阻尼环路中引入二阶谐振环节,利用频域分析法给出了相关参数的设计过程,可有效扩大Z_(eq)(s)的正阻特性范围,并网逆变器在弱电网下的鲁棒性得到增强。最后,通过仿真验证了改进型方法的合理性和有效性。

关键词：电容电流比例有源阻尼数字控制延时虚拟电阻二阶谐振环节

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More Requests, Less Cost： Uncertain Inter-Datacenter Traffic Transmission with Multi-Tier Pricing

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Journal of Computer Science & Technology 2018年第6期33卷 1152-1163页

作者： xiao-dong dong Sheng Chen Lai-Ping Zhao xiao-Bo Zhou Heng Qi Ke-Qiu Li Tianjin Key Laboratory of Advanced Networking College of Intelligence and Computing Tianjin University Tianjin 300350 China School of Computer Science and Technology Dalian University of Technology Dalian 116024 China

With the multi-tier pricing scheme provided by most of the cloud service providers （CSPs）, the cloud userstypically select a high enough transmission service level to ensure the quality of service （QoS）, due to the severe penalty ofmissing the transmission deadline. This leads to the so-called over-provisioning problem, which increases the transmissioncost of the cloud user. Given the fact that cloud users may not be aware of their traffic demand before accessing the network,the over-provisioning problem becomes more serious. In this paper, we investigate how to reduce the transmission cost fromthe perspective of cloud users, especially when they are not aware of their traffic demand before the transmission *** key idea is to split a long-term transmission request into several short ones. By selecting the most suitable transmissionservice level for each short-term request, a cost-efiqcient inter-datacenter transmission service level selection framework isobtained. We further formulate the transmission service level selection problem as a linear programming problem andresolve it in an on-line style with Lyapunov optimization. We evaluate the proposed approach with real traffic data. Theexperimental results show that our method can reduce the transmission cost by up to 65.04%.

关键词： traffic uncertainty inter-datacenter transmission multi-tier pricing scheme

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Laponite:a promising nanomaterial to formulate high-performance water-based drilling fluids

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Petroleum Science 2021年第2期18卷 579-590页

作者： Xian-Bin Huang Jin-Sheng Sun Yi Huang Bang-Chuan Yan xiao-dong dong Fan Liu Ren Wang Key Laboratory of Unconventional Oil and Gas Development China University of Petroleum(East ChinaMinistry of Education)Qingdao266580ShandongPeople’s Republic of China School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongPeople’s Republic of China Zhanjiang Branch of China National Offshore Oil Corporation Limited Zhanjiang524057GuangdongChina CNPC Engineering Technology R&D Company Limited Beijing102206People’s Republic of China

High-performance water-based drilling fluids(HPWBFs)are essential to wellbore stability in shale gas exploration and *** is a synthetic hectorite clay composed of disk-shaped *** paper analyzed the application potential of laponite in HPWBFs by evaluating its shale inhibition,plugging and lubrication *** inhibition performance was studied by linear swelling test and shale recovery *** performance was analyzed by nitrogen adsorption experiment and scanning electron microscope(SEM)*** pressure lubricity test was used to evaluate the lubrication *** results show that laponite has good shale inhibition property,which is better than commonly used shale inhibitors,such as polyamine and *** can effectively plug shale *** considerably decreases the surface area and pore volume of shale,and SEM results show that it can reduce the porosity of shale and form a seamless *** is beneficial to increase lubricating property of drilling fluid by enhancing the drill pipes/wellbore interface smoothness and isolating the direct contact between wellbore and drill ***,laponite can reduce the fluid loss *** to mechanism analysis,the good performance of laponite nanoparticles is mainly attributed to the disk-like nanostructure and the charged surfaces.

关键词： Laponite Nanoparticles High performance Drilling fluid Shale gas

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On Minor Left Prime Factorization Problem for Multivariate Polynomial Matrices

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Journal of Systems Science & Complexity 2024年第3期37卷 1295-1307页

作者： LU dong WANG Dingkang xiao Fanghui School of Mathematics Southwest Jiaotong UniversityChengdu 610031China KLMM Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China MOE-LCSM School of Mathematics and StatisticsHunan Normal UniversityChangsha 410081China

A new necessary and sufficient condition for the existence of minor left prime factorizations of multivariate polynomial matrices without full row rank is *** key idea is to establish a relationship between a matrix and any of its full row rank *** on the new result,the authors propose an algorithm for factorizing matrices and have implemented it on the computer algebra system *** examples are given to illustrate the effectiveness of the algorithm,and experimental data shows that the algorithm is efficient.

关键词： Free modules Grobner bases minor left prime(MLP) multivariate polynomial matrices polynomial matrix factorizations

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Treatment of type C3 distal radius fracture resulted from high-energy injuries by volar plate in combination with external fixator

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Chinese Medical Journal 2009年第13期122卷 1517-1520页

作者： ZHANG Qiu-lin ZHU xiao-dong LI Guo-dong TANG Hao LI Ming WU Da-jiang Department of Orthopedics Changhal Hospital Second Military Medical University Shanghai 200433 China

Background With a type C3 distal radius fracture it is extremely difficult to maintain the reduction and to restore congruity of the articular surface because the support for the volar and dorsal bone cortex has been lost. An external fixator crossing wrist in combination with Kirschner wire （K-wire） fixation was popularly used by most studies in recent years. But loss of reduction often occurred especially in the volar sides. Methods A total of 30 cases of type C3 distal radius fracture were treated by a volar buttress plate combined with a transarticular external fixator and other techniques such as K-wire fixation and bone grafting if necessary. The postoperative volar tilt angles, ulnar inclinations, radial heights, range of motion, grip strength and complications were recorded to assess the therapeutic effects. Results Of the 30 patients, 27 patients were followed up for 12-29 （mean 18） months and all fractures healed in 8-13 weeks after surgery （mean 10 weeks）. The wrist function was excellent in 8 cases, good in 16 cases and fair in 3 cases according to the Sarmiento scoring system （modified by Stewart）. Conclusions For type C3 comminuted fracture with severe volar and dorsal instability, fixation by volar buttress plate combined with transarticular external fixator should be adopted. Dorsal instability could be further stabilized by other techniques such as Kirschner wire fixation, and bone grafting.

关键词： distal radius fracture internal fixation external fixator

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Current understanding of ELF4 deficiency:a novel inborn error of immunity

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World Journal of Pediatrics 2024年第5期20卷 444-450页

作者： Hong-Qiang Du xiao-dong Zhao Department of Rheumatology&Immunology National Clinical Research Center for Child Health and DisordersMinistry of Education Key Laboratory of Child Development and DisordersChongqing Key Laboratory of Child Rare Diseases in Infection and ImmunityChildren’s Hospital of Chongqing Medical UniversityZhongshan Er Road 136Yuzhong DistrictChongqingChina

Background ELF4 deficiency has been recently recognized as a novel disorder within the spectrum of inborn errors of immunity(IEIs),specifically categorized as a“disease of immune dysregulation.”Cases of this condition,reported by our team and others,are very limited *** such,our current knowledge of this new disease remains *** review aims to provide a brief overview of the clinical manifestations,pathogenesis,and treatment strategies for this novel *** sources A comprehensive review was conducted after an extensive literature search in the PubMed/Medline database and websites concerning transcriptional factor ELF4 and reports concerning patients with ELF4 *** search strategy was“ELF4 OR ETS-related transcription factor Elf-4 OR EL4-like factor 4 OR myeloid Elf-1-like factor”as of the time of manuscript *** The current signature manifestations of ELF4 deficiency disorder are recurrent and prolonged oral ulcer,abdominal pain,and diarrhea in pediatric *** some cases,immunodeficiency and autoimmunity can also be *** Sanger sequencing or whole exome sequencing can be used to detect variation in ELF4 *** blotting for ELF4 expression of the patient’s cells can confirm the pathogenic effect of the *** fully confirm the pathogenicity of the variant,further functional test is strongly *** and biologics are the mainstream management of ELF4 deficiency *** Pediatric males presenting with recurring ulcerations in digestive tract epithelium with or without recurrent fever should be suspected of *** atypical presentations are prominent,variations in ELF4 gene should be carefully evaluated functionally due to the complex nature of ELF4 *** of treating DEX includes use of glucocorticoid and biologics and more precise treatment needs more patients to identify and further mechanistic study.

关键词： ELF4 transcription factor Immune dysregulation Inborn errors of immunity Mechanism Recurrent infections

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Notoginsenoside as an environmentally friendly shale inhibitor in water-based drilling fluid

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Petroleum Science 2022年第2期19卷 608-618页

作者： Jin-Sheng Sun Zong-Lun Wang Jing-Ping Liu Kai-He Lv Fan Zhang Zi-Hua Shao xiao-dong dong Zhi-Wen Dai Xian-Fa Zhang College of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongPeople's Republic of China Key Laboratory of Unconventional Oil&Gas Development(China University of Petroleum(East China)) Ministry of EducationQingdao266580ShandongPeople's Republic of China

The demand for non-toxic and biodegradable shale inhibitors is growing in the drilling *** this paper,the effect of notoginsenoside(NS)as a new,environmentally friendly inhibitor of shale hydration is systematically studied for the first *** inhibition performance of NS was evaluated via inhibition evaluation tests,including mud ball immersion tests,linear expansion tests,shale rolling recovery tests,and compressive strength *** inhibition mechanism of NS was analyzed using Fourier transform infrared spectroscopy(FTIR),contact angle measurements,particle size distribution determination,thermogravimetric analysis(TGA),and scanning electron microscopy(SEM).The experimental results demonstrate that NS is able to adhere to the clay surface,forming a hydrophobic film that prevents the entry of water molecules and inhibiting the hydration dispersion of the *** of this,NS can maintain the original state of bentonite pellets in water,which can effectively reduce the swelling rate of bentonite,increase the recovery rate of shale drill cuttings,maintain the strength of the shale,and therefore maintain the stability of the borehole wall during *** addition,NS is non-toxic,degradable,and compatible with water-based drilling *** above advantages make NS a promising candidate for use as an environmentally friendly shale inhibitor.

关键词： Notoginsenoside Shale inhibition Environmentally friendly Water-based drilling fluid Inhibition mechanism

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Investigation of high rate mechanical flow followed by ignition for high-energy propellant under dynamic extrusion loading

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Defence Technology（防务技术） 2024年第2期32卷 336-347页

作者： Liying dong Yanqing Wu Kun Yang xiao Hou State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China

Investigating the ignition response of nitrate ester plasticized polyether(NEPE) propellant under dynamic extrusion loading is of great significant at least for two cases. Firstly, it helps to understand the mechanism and conditions of unwanted ignition inside charged propellant under accident ***, evaluates the risk of a shell crevice in a solid rocket motor(SRM) under a falling or overturning scene. In the present study, an innovative visual crevice extrusion experiment is designed using a dropweight apparatus. The dynamic responses of NEPE propellant during extrusion loading, including compaction and compression, rapid shear flow into the crevice, stress concentration, and ignition reaction, have been firstly observed using a high-performance high-speed camera. The ignition reaction is observed in the triangular region of the NEPE propellant sample above the crevice when the drop weight velocity was 1.90 m/s. Based on the user material subroutine interface UMAT provided by finite element software LS-DYNA, a viscoelastic-plastic model and dual ignition criterion related to plastic shear dissipation are developed and applied to the local ignition response analysis under crevice extrusion conditions. The stress concentration occurs in the crevice location of the propellant sample, the shear stress is relatively large, the effective plastic work is relatively large, and the ignition reaction is easy to occur. When the sample thickness decreases from 5 mm to 2.5 mm, the shear stress increases from 22.3 MPa to 28.6 MPa, the critical value of effective plastic work required for ignition is shortened from 1280 μs to 730 μs, and the triangular area is easily triggering an ignition reaction. The propellant sample with a small thickness is more likely to stress concentration, resulting in large shear stress and effective work, triggering an ignition reaction.

关键词： NEPE propellant Crevice extrusion Shear flow Sample thickness Ignition reaction

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