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Degradable preformed particle gel as temporary plugging agent for low-temperature unconventional petroleum reservoirs:Effect of molecular weight of the cross-linking agent

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Petroleum Science 2022年第6期19卷 3182-3193页

作者： Hong-Jun Zhang Dao-Yi Zhu Yong-Long Gong Jun-Hui Qin Xiao-Ning Liu yuan-hang pi Qi Zhao Run-Tian Luo Wan-Sheng Wang Ke-Ke Zhi Zong-Jie Mu China University of Petroleum-Beijing at Karamay KaramayXinjiang834000China

The development of unconventional petroleum resources has gradually become an important succession for increasing oil ***,the related engineers and researchers are paying more and more attention to the application of temporary plugging agents(TPAs)for their efficient *** can expand the stimulated reservoir volume(SRV)and facilitate the flow of oil and gas to the bottom of the ***-gels used as temporary plugging agents have the characteristics of the simple injection process,good deformation,high plugging strength,and complete self-degradation performance,which have been widely applied in recent *** this paper,five samples of DPPG polymerized by different molecular weights of cross-linking agents were *** addition,infrared spectroscopy analysis,differential calorimetry scanning(DSC)analysis,static particle gel swelling and degradation performance evaluation experiments,and dynamic temporary plugging performance experiments in cores were conducted at 34°*** show that as the molecular weight of the cross-linking agent(at 0.01 g)in the DPPG molecule decreased from 1,000 to 200 Da,the fewer cross-linking sites of DPPG,the looser the microscopic three-dimensional mesh structure *** swelling ratio increased from 7 to 33 ***,the complete degradation time increased from 40 to 210 ***,the DSC results confirmed that the higher the molecular weight of the cross-linking agent,the worse is chemical stability and the more prone it to *** samples had good temporary plugging performance in reservoir *** prepared by the cross-linking agent with smaller molecular weight has a stronger swelling ratio,higher gel strength,and greater plugging strength in the core ***,the degraded DPPG is less damaging to the ***,their slower degradation rates take a slightly longer times to reach complete *** results of this paper can provide new ideas and

关键词： Temporary plugging agent Preformed particle gel Degradable cross-linking agent Molecular weight Low-temperature reservoir

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爆炸切割网络传爆中的间隙与角度效应

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火工品 2025年第1期 37-43页

作者：周晓鹏姜勇袁航中国船舶集团有限公司第七一三研究所河南郑州450015 河南省水下智能装备重点实验室河南郑州450015

为研究爆炸切割网络中传爆节点处传爆能力的关键影响因素,通过改变切割索对传爆药柱的传爆间隙进行了平板传爆试验,将试验结果结合仿真分析确定了JO-11C传爆药柱的仿真材料参数,并进一步分析了传播角度对传爆能力的影响。研究结果表明:... 详细信息

为研究爆炸切割网络中传爆节点处传爆能力的关键影响因素,通过改变切割索对传爆药柱的传爆间隙进行了平板传爆试验,将试验结果结合仿真分析确定了JO-11C传爆药柱的仿真材料参数,并进一步分析了传播角度对传爆能力的影响。研究结果表明:随着传爆间隙的增加,传爆能力下降,切割索对传爆药柱的最大传爆间隙区间为2.0~2.5 mm;同时,传爆角度的增大能够显著提高传爆能力。本研究为爆炸切割网络的传爆性能研究以及提高武器系统的可靠性提供了参考。

关键词：爆炸切割网络传爆间隙传爆角度传爆药柱仿真分析

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Inhibition of the cGAS–STING pathway:contributing to the treatment of cerebral ischemia-reperfusion injury

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Neural Regeneration Research 2025年第7期20卷 1900-1918页

作者： hang Yang Yulei Xia Yue Ma Mingtong Gao Shuai Hou Shanshan Xu Yanqiang Wang School of Clinical Medicine Shandong Second Medical UniversityWeifangShandong ProvinceChina Department of Emergency The Affiliated Hospital of Weifang Medical UniversityWeifangShandong ProvinceChina Department of Neurology Ⅱ The Affiliated Hospital of Weifang Medical UniversityWeifangShandong ProvinceChina

The cGAS–STING pathway plays an important role in ischemia-reperfusion injury in the heart,liver,brain,and kidney,but its role and mechanisms in cerebral ischemia-reperfusion injury have not been systematically ***,we outline the components of the cGAS–STING pathway and then analyze its role in autophagy,ferroptosis,cellular pyroptosis,disequilibrium of calcium homeostasis,inflammatory responses,disruption of the blood–brain barrier,microglia transformation,and complement system activation following cerebral ischemia-reperfusion *** further analyze the value of cGAS–STING pathway inhibitors in the treatment of cerebral ischemia-reperfusion injury and conclude that the pathway can regulate cerebral ischemia-reperfusion injury through multiple *** of the cGAS–STING pathway may be helpful in the treatment of cerebral ischemia-reperfusion injury.

关键词： calcium homeostasis cellular autophagy cerebral ischemia-reperfusion injury cGAS–STING pathway ferroptosis gut–brain–microbiota axis inflammatory light chain 3 microglial cells Syntaxin-17 protein

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Free Vibration Analysis of Moderately-Thick Laminated Doubly-Curved Shells with the Modified Higher-Order Theory

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Acta Mechanica Solida Sinica 2023年第1期36卷 132-142页

作者： yuan Tao Jie Xu Xuegang yuan hang Yin School of Mathematics Boda College of Jilin Normal UniversitySiping 136000China Department of Mechanics Northeastern UniversityShenyang 110819China School of Science Dalian Minzu UniversityDalian 116600China

In this work,the free vibration properties ofmoderately-thick laminated doubly-curved shells are *** model of the natural frequency of the simply-supported laminated doubly-curved shell is formulated via the variational *** on the numerical solutions,the influences of the shell type,the aspect ratio,the lamination angle and the layer number on the free vibration are *** obtained results show that,for the symmetrically laminated curved shells with fixed thickness,when the layer number is greater than 4,the increasing number has no impact on the natural frequency;however,the lamination angle plays a key role in the fundamental frequency of the spherical shell,while it has little effect on the hyperbolic paraboloid ***,a higher-order shear deformation theory with modified parameters is developed for the moderately-thick laminated doubly-curved shells in this work,i.e.,the geometrically nonlinear strain–displacement relationships are derived with a stricter series expansion form,which are more suitable for the moderately-thick curved shells.

关键词： Vibration analysis Laminated doubly-curved shell Modified displacement fields Higher-order shear deformation

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Shape of slab solidification end under non-uniform cooling and its influence on the central segregation with mechanical soft reduction

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International Journal of Minerals,Metallurgy and Materials 2021年第11期28卷 1788-1798页

作者： Jie Li Yan-hui Sun hang-hang An Pei-yuan Ni Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China School of Metallurgy Northeastern UniversityShenyang 110819China Hesteel Group Technology Research Institute Shijiazhuang 050000China

In order to study the effect of continuous casting process parameters on the shape of slab solidification end under non-uniform cooling,a solidification model of a continuous-cast slab with non-uniform cooling condition was established with ProCAST *** model was verified by the results of nail shooting tests and the infrared temperature measurement *** characteristic parameters were defined to evaluate the uniformity of the shape of slab solidification *** results showed that the nonuniformity at the beginning and end of solidification,the solidification end length,and the solidification unevenness increased with the rise of casting *** each 10°C increase of superheat,the solidification unevenness increased by about ***,the effect of superheat on the solidification end length can be *** secondary cooling strength showed minimal effect on the nonuniformity at the beginning and end of *** the increase in secondary cooling intensity,the solidification end length decreased,but the solidification unevenness *** addition,the central segregation of the slab produced with and without the mechanical soft reduction(MSR)process was *** transverse flow of molten steel with low solid fraction influenced the central segregation morphology under MSR.

关键词： continuous casting heat transfer model nail shooting shape of solidification end central segregation

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ACCELERATION METHODS OF NONLINEAR ITERATION FOR NONLINEAR PARABOLIC EQUATIONS

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Journal of Computational Mathematics 2006年第3期24卷 412-424页

作者： Guang-wei yuan Xu-deng hang Laboratory of Computational Physics Institute of Applied Physics and Computational Mathematics P.O.Box 8009 Beijing 100088 China

This paper discusses the accelerating of nonlinear parabolic equations. Two iterative methods for solving the implicit scheme new nonlinear iterative methods named by the implicit-explicit quasi-Newton （IEQN） method and the derivative free implicit-explicit quasi-Newton （DFIEQN） method are introduced, in which the resulting linear equations from the linearization can preserve the parabolic characteristics of the original partial differential equations. It is proved that the iterative sequence of the iteration method can converge to the solution of the implicit scheme quadratically. Moreover, compared with the Jacobian Free Newton-Krylov （JFNK） method, the DFIEQN method has some advantages, e.g., its implementation is easy, and it gives a linear algebraic system with an explicit coefficient matrix, so that the linear （inner） iteration is not restricted to the Krylov method. Computational results by the IEQN, DFIEQN, JFNK and picard iteration methods are presented in confirmation of the theory and comparison of the performance of these methods.

关键词： Nonlinear parabolic equations Difference scheme Newton iterative methods.

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Hybrid Precoding for Cluster-Based Multi-Carrier Beam Division Multiple Access in Terahertz Wireless Communications

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China Communications 2021年第5期18卷 81-92页

作者： hang yuan Xiang Wang Kai Yang Jianping An School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China National Innovation Institute of Defense Technology Chinese Academy of Military ScienceBeijing 100000China

Terahertz(THz)wireless communication has the capability to connect massive devices using its ultra-large spectrum *** propose a hybrid precoding scheme for the cluster-based multi-carrier beam division multiple access(MC-BDMA)to enable THz massive *** the inter-beam interference and inter-band power leakage in this system are considered.A mathematical model is established to analyze and reduce their effects on the THz signal *** considering the peculiarities of THz channels and characteristics of THz hardware components,we further propose a three-step hybrid precoding algorithm with low complexity,where the received signal power enhancement,the inter-beam interference elimination,and the inter-band power leakage suppression are conducted in *** results are presented to demonstrate the high spectrum efficiency and high energy efficiency of our proposed algorithm,especially in the massive-connection scenarios.

关键词： terahertz wireless communications multicarrier hybrid precoding power leakage suppression

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Matching design of hydraulic load simulator with aerocraft actuator

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Chinese Journal of Aeronautics 2013年第2期26卷 470-480页

作者： Shang Yaoxing yuan hang Jiao Zongxia Yao Nan Science and Technology on Aerocraft Control Laboratory School of Automation Science and Electrical Engineering Beihang University

This paper intends to provide theoretical basis for matching design of hydraulic load simulator （HLS） with aerocraft actuator in hardware-in-loop test, which is expected to help actuator designers overcome the obstacles in putting forward appropriate requirements of HLS. Traditional research overemphasizes the optimization of parameters and methods for HLS controllers. It lacks deliberation because experimental results and project experiences indicate different ultimate performance of a specific HLS. When the actuator paired with this HLS is replaced, the dynamic response and tracing precision of this HLS also change, and sometimes the whole system goes so far as to lose control. Based on the influence analysis of the preceding phenomena, a theory about matching design of aerocraft actuator with HLS is presented, together with two paired new concepts of ＂Standard Actuator＂ and ＂Standard HLS＂. Further research leads to seven important conclusions of matching design, which suggest that appropriate stiffness and output torque of HLS should be carefully designed and chosen for an actuator. Simulation results strongly support that the proposed principle of matching design can be anticipated to be one of the design criteria for HLS, and successfully used to explain experimental phenomena and project experiences.

关键词： Aerocraft actuator Design Flight simulation Hydraulic drive and control Hydraulic load simulator (HLS) Matching Servo control Stiffness

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Squeeze flow of interstitial Herschel-Bulkley fluid between two rigid spheres

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Particuology 2010年第4期8卷 360-364页

作者： Chunhui Xu Li yuan Yong Xu Wenbin hang College of Science China Agricultural University Beijing 100083 China

Interaction between two spheres with an interstitial fluid is crucial in discrete element modeling for simulating the behaviors of ＇wet＇ particulate materials. The normal viscous force of squeeze flow between two arbitrary rigid spheres with an interstitial HerscheI-Bulkley fluid was studied on the basis of Reynolds＇ lubrication theory, resulting in analytical integral expressions of pressure distribution and the viscous force between the two spheres. According to the variation of shear stress, the fluid was divided into yielding and unyielding regions, followed by a discussion on the thickness of the two regions. The result of this paper could be reduced to either the power-law fluid or the Bingham fluid case.

关键词： Wet granuleDiscrete element method Herschel-Bulldey fluid Viscous force

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Monkeypox virus:past and present

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World Journal of Pediatrics 2023年第3期19卷 224-230页

作者： Ya-Mei Dou hang yuan Hou-Wen Tian NHC Key Laboratory of Medical Virology and Viral Disease Chinese Center for Disease Control and PreventionNational Institute for Viral Disease Control and Prevention155 Changbai RoadChangPing DistrictBeijing 102206China

Background The objective of this paper is to analyze the current status of monkeypox *** the face of this public health threat,our purpose is to elucidate the clinical characteristics and epidemiology of monkeypox,the developmental progress of monkeypox-related drugs and the vaccines *** sources The literature review was performed in databases including PubMed,Science Direct and Google Scholar up to July *** Since May 2022,the World Health Organization has reported more than 45,000 confirmed cases from 92 nonendemic countries,including nine *** some women and children have been infected so far,most cases have occurred among men who have sex with other men,especially those with multiple sexual partners or anonymous *** Pediatric monkeypox infection has been associated with a higher likelihood of severe illness and mortality than in *** monkeypox illness in pediatrics often requires adjunctive antiviral *** is crucial for all countries to establish sound monitoring and testing systems and be prepared with emergency preparedness.

关键词： Monkeypox Orthopoxvirus Smallpox Zoonotic

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