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Failure evolution and disaster prediction of rock under uniaxial compression based on non-extensive statistical analysis of electric potential

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International Journal of Mining Science and Technology 2024年第7期34卷 975-993页

作者： Tiancheng shan Zhonghui Li Haishan jia Enyuan Wang Xiaoran Wang Yue Niu Xin Zhang Dong Chen shan Yin Quancong Zhang State Key Laboratory of Coal Mine Disaster Prevention and Control China University of Mining and TechnologyXuzhou 221116China National Engineering Research Center for Coal Gas Control China University of Mining and TechnologyXuzhou 221116China School of Safety Engineering China University of Mining and TechnologyXuzhou 221116China State Key Laboratory for Fine Exploration and Intelligent Development of Coal Resources China University of Mining and TechnologyXuzhou 221116China State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhou 221116China

Rock failure can cause serious geological disasters,and the non-extensive statistical features of electric potential(EP)are expected to provide valuable information for disaster *** this paper,the uniaxial compression experiments with EP monitoring were carried out on fine sandstone,marble and granite samples under four displacement *** Tsallis entropy q value of EPs is used to analyze the selforganization evolution of rock *** the influence of displacement rate and rock type on q value are explored by mineral structure and fracture modes.A self-organized critical prediction method with q value is *** results show that the probability density function(PDF)of EPs follows the q-Gaussian *** displacement rate is positively correlated with q *** the displacement rate increasing,the fracture mode changes,the damage degree intensifies,and the microcrack network becomes *** influence of rock type on q value is related to the burst intensity of energy release and the crack fracture *** q value of EPs can be used as an effective prediction index for rock failure like b value of acoustic emission(AE).The results provide useful reference and method for the monitoring and early warning of geological disasters.

关键词： Electric potential Non-extensive statistical feature Displacement rate q-Gaussian distribution Precursor prediction Rock materials

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Efficacy and safety of Yiqi Peiyuan granules for improving the short-term prognosis of patients with acute kidney injury:A multicenter,double-blind,placebo-controlled,randomized trial

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Journal of Integrative Medicine 2024年第3期22卷 279-285页

作者： jia-jia Wu Tian-yi Zhang Ying-hui Qi Min-yan Zhu Yan Fang Chao-jun Qi Li-ou Cao Ji-fang Lu Bo-han Lu Lu-min Tang jian-xiao shen shan Mou Department of Nephrology Molecular Cell Lab for Kidney DiseaseShanghai Peritoneal Dialysis Research CenterUremia Diagnosis and Treatment CenterRenji Hospital Affiliated to Shanghai Jiaotong University School of MedicineShanghai 200127China Department of Nephrology Shanghai Pudong New Area Punan HospitalShanghai 200125China Department of Nephrology Ningbo Hangzhou Bay HospitalNingbo 315336Zhejiang ProvinceChina

Background:Yiqi Peiyuan(YQPY)prescription,a composite prescription of traditional Chinese medicine,has been used to prevent or delay the continued deterioration of renal function after acute kidney injury(AKI)in some institutions and has shown considerable ***:This is the first randomized controlled trial to assess efficacy and safety of YQPY for improving short-term prognosis in adult patients with ***,setting,participants and interventions:This is a prospective,double-blind,multicenter,randomized,and placebo-controlled clinical trial.A total of 144 enrolled participants were randomly allocated to two groups according to a randomization ***,caregivers and investigators assessing the outcomes were blinded to group *** in the YQPY group received 36 g YQPY granules twice a day for 28 *** in the placebo group received a placebo in the same dose as the YQPY *** outcome measures:The primary outcome was the change in the estimated glomerular filtration rate(eGFR)between baseline and after 4 and 24 weeks of *** secondary outcomes were the change of serum creatinine(Scr)level between baseline and after treatment,and the incidence of endpoint events,defined as eGFR increasing by more than 25%above baseline,eGFR>75 mL/min per1.73 m2or the composite endpoint,which was defined as the sum of patients meeting either of the above ***:Data from a total of 114 patients(59 in the YQPY group and 55 in the control group)were *** mean changes in eGFR and Scr in weeks 4 and 24 had no difference between the two *** further subgroup analysis(22 in the YQPY group and 31 in the control group),the mean change in eGFR after treatment for 4 weeks was 27.39 mL/min per 1.73 m2in the YQPY group and 5.78 mL/min per1.73 m2in the placebo group,and the mean difference between groups was 21.61 mL/min per 1.73 m2(P<0.001).Thirteen(59.1%)patients in the YQPY group and 5(16.1%)in the placebo g

关键词： Chinese herbal medicine Randomized controlled trial Acute kidney injury Renal function

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Evolution and Application of Sealing Ability of Gypsum Caprocks under Temperature-Pressure Coupling:An Example of the ZS5 Well in the Tazhong Area of the Tarim Basin

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 168-184页

作者： LIU Hua ZHAO shan YANG Xianzhang ZHU Yongfeng WANG shen ZHANG Ke National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)QingdaoShandong 266580China School of Geosciences China University of Petroleum(East China)QingdaoShandong 266580China Laboratory for Marine Mineral Resources National Laboratory for Marine Science and TechnologyQingdaoShandong 266071China PetroChina Tarim Oil Field Company KorlaXinjiang 841001China

Gypsum caprocks'sealing ability is affected by temperature-pressure *** to the limitations of experimental conditions,there is still a lack of triaxial stress-strain experiments that simultaneously consider changes in temperature and pressure conditions,which limits the accuracy of the comprehensive evaluation of the brittle plastic evolution and sealing ability of gypsum rocks using temperature pressure *** stress-strain tests were utilized to investigate the differences in the evolution of the confinement capacity of gypsum rocks under coupled temperaturepressure action and isothermal-variable pressure action on the basis of sample feasibility *** to research,the gypsum rock's peak and residual strengths decrease under simultaneous increases in temperature and pressure over isothermal pressurization experimental conditions,and it becomes more *** reduces the amount of time it takes for the rock to transition from brittle to *** temperature is taken into account,both the brittle–plastic transformation's depth limit and the lithological transformation of gypsum rocks become shallower,and the evolution of gypsum rocks under variable temperature and pressure conditions is more complicated than that under isothermal *** sealing ability under the temperature-pressure coupling is more in line with the actual geological context when the application results of the Well#ZS5 are *** provides a theoretical basis for precisely determining the process of hydrocarbon accumulation and explains why the early hydrocarbon were not well preserved.

关键词： temperature-pressure coupling gypsum caprocks brittle-plastic evolution sealing capacity Tarim Basin

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保留一侧杓状软骨的喉次全切除术的远期疗效观察

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中华耳鼻咽喉头颈外科杂志 2005年第1期40卷 49-51页

作者：贾深汕孙冀裴荣哈尔滨医科大学附属肿瘤医院头颈外科 150040

目的　探讨保留一侧杓状软骨的喉次全切除术的疗效。方法　分析 82例 (Ⅲ期 73例 ,Ⅳ期 9例 ;声门上型 71例 ,声门型 6例 ,跨声门型 5例 )喉鳞状细胞癌患者施行保留一侧杓状软骨的喉次全切除术的远期疗效。结果　 82例均恢复了发音及吞... 详细信息

目的　探讨保留一侧杓状软骨的喉次全切除术的疗效。方法　分析 82例 (Ⅲ期 73例 ,Ⅳ期 9例 ;声门上型 71例 ,声门型 6例 ,跨声门型 5例 )喉鳞状细胞癌患者施行保留一侧杓状软骨的喉次全切除术的远期疗效。结果　 82例均恢复了发音及吞咽功能 ,呼吸功能恢复正常者 84 2 % (6 9/82 )。 82例中发生咽瘘 2例 ,创口感染 6例 ,均保守治愈。 82例随访均满 5年以上 ,失访 5例 ,随访率为 93 9%。 5年内死亡 2 6例 ,其中喉癌局部复发 5例 ,颈淋巴结转移 4例 ,喉癌复发及颈淋巴结转移 4例 ,其他 4例 (心功能衰竭、心肌梗死、肺转移、直肠癌各 1例 ) ,死因不明 4例 ,失访 5例。随访满 10年者 6 8例 ,死亡 30例 (包括 5年内死亡之 2 6例 ,5年后死于喉癌复发 1例 ,死因不明 2例 ,失访 1例 ) ,5、10年生存率分别为 6 8 3% (5 6 /82 )及 5 5 9% (38/6 8)。

关键词：杓状软骨喉次全切除术喉肿瘤并发症喉鳞状细胞癌

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Significantly Enhanced Melt Memory Effect of Metallocene-made Isotactic Polypropylene Containing Talc

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Chinese Journal of Polymer Science 2024年第2期42卷 213-222,I0008页

作者： Hong-Wen Sun Fu-shan Wang Yan Gao Fu-Qing Wei jia-Chun Feng State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai200433China Lanzhou Petrochemical Corporation of PetroChina Lanzhou730060China Lanzhou Petrochemical Research Center Petrochemical Research Institute of PetroChinaLanzhou730060China

The melt memory effect is a widely observed phenomenon in semi-crystalline polymers. In practical applications, various additives are usually introduced into polymers, which may affect their melt memory behavior. In this work, the effect of talc on the melt memory effect of metallocene-made isotactic polypropylene(M-PP) was investigated in detail by using the differential scanning calorimetry. The results indicated that the introduction of talc significantly strengthened the melt memory effect of M-PP. Specifically, the upper limit temperature of Domain II increased from 161 ℃ to 174 ℃, resulting in a substantial widening of the temperature range of Domain IIa from 1 ℃ to 14 ℃. Analysis of the crystal orientation of the M-PP containing talc cooled from various Ts suggested that the remarkably enhanced melt memory effect could be ascribed to the stabilization of oriented nuclei facilitated by talc. This stabilizing effect was likely attributable to the prefreezing effect or the sorption interaction between talc and the M-PP chains.

关键词： Metallocene-made isotactic polypropylene Talc Melt memory effect Crystal orientation

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Synthetic auxotrophs accelerate cell factory development through growth-coupled models

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Frontiers of Chemical Science and Engineering 2024年第9期18卷 73-87页

作者： Liangpo Li Linwei Yu Xinxiao Sun Qipeng Yuan Xiaolin shen jia Wang State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China

The engineering of microbial cell factories for the production of high-value chemicals from renewable resources presents several challenges,including the optimization of key enzymes,pathway fluxes and metabolic *** these challenges involves the development of synthetic auxotrophs,a strategy that links cell growth with enzyme properties or biosynthetic *** linkage allows for the improvement of enzyme properties by in vivo directed enzyme evolution,the enhancement of metabolic pathway fluxes under growth pressure,and remodeling of metabolic networks through directed strain *** advantage of employing synthetic auxotrophs lies in the power of growth-coupled selection,which is not only high-throughput but also labor-saving,greatly simplifying the development of both strains and *** auxotrophs play a pivotal role in advancing microbial cell factories,offering benefits from enzyme optimization to the manipulation of metabolic networks within single ***,this strategy extends to coculture systems,enabling collaboration within microbial *** review highlights the recently developed applications of synthetic auxotrophs as microbial cell factories,and discusses future perspectives,aiming to provide a practical guide for growth-coupled models to produce value-added chemicals as part of a sustainable biorefinery.

关键词： synthetic auxotrophs growth-coupled directed enzyme evolution pathway flux directed strain evolution coculture

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Research on slim-hole drilling technology for shale gas geological survey in China

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PETROLEUM RESEARCH 2024年第3期9卷 451-461页

作者： Zhao, Hongbo Wu, Haixia shen, Lina Zhu, Zhitong shan, Yansheng China Geol Survey Oil & Gas Survey Beijing 100083 Peoples R China Beijing Inst Explorat Engn Beijing 100083 Peoples R China Chinese Acad Geol Sci Inst Explorat Tech Langfang 065000 Peoples R China

Over the last 10 years, the China Geological Survey has deployed 137 slim-hole shale gas geological exploration wells for coring entire wellbores. These wells are primarily located in new blocks and geological formations where neighboring well data are insufficient, beyond the scope of developed oil fields in China, or outside of oil and gas company mining-right areas. The drilling rig equipment, coring tools, and core drill bits of slim-hole shale gas drilling technology are different from those associated with traditional petroleum drilling. Many studies have been conducted on non-coring slim-hole drilling technology. This paper focuses on coring technology and drilling safety, summarizing a set of high- efficiency shale gas drilling equipment and technology systems based on geological drilling equipment and techniques (that can be used for solid mineral exploration). We report on: 1) an improved vertical shaft drilling rig adapted to shale gas well control safety; 2) high-efficiency core drilling techniques, focusing on coring tools, and techniques incorporating an inverted tower drilling tool combination, air circulation follow-through technology, and expanded casing technology; 3) research progress on high- efficiency core drill bits, including non-planar tooth polycrystalline diamond compact bits and impregnated diamond core bits, along with their application effects. This research provides substantial advances in drill-core technology and improvements in exploration efficiency. Moreover, it provides a reference frame for well structural design and selection of construction technology for shale gas exploration drilling projects. (c) 2024 The Authors. Publishing services provided by Elsevier B.V. on behalf of KeAi Communication Co. Ltd. This is an open access article under the CC BY-NC-ND license .

关键词： Shale gas Slim-hole drilling technology Core drilling tools Core drill bits China RESEARCH PROGRESS EXPLORATION DISCOVERY

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Simultaneous Bulk-and Surface-initiated Living Polymerization Studied with a Heterogeneous Stochastic Reaction Model

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Chinese Journal of Polymer Science 2024年第3期42卷 364-372,I0008页

作者： jia-Shu Ma Zhi-Ning Huang jia-Hao Li Bang-Ping jiang Yan-Da Liao Shi-Chen Ji Xing-Can shen State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources(Ministry of Education of China)School of Chemistry and Pharmaceutical SciencesGuangxi Normal UniversityGuilin 541004China School of Computer Science and Engineering&School of Software Guangxi Normal UniversityGuilin 541004China

To better characterize the properties of surface-initiated polymers, simultaneous bulk-and surface-initiated polymerizations are usually carried out by assuming that the properties of the surface-initiated polymers resemble those of the bulk-initiated polymers. Through a Monte Carlo simulation using a heterogeneous stochastic reaction model, it was discovered that the bulk-initiated polymers exhibit a higher molecular weight and a lower dispersity than the corresponding surface-initiated polymers, which indicates that the equivalent assumption is invalid. Furthermore, the molecular weight distributions of the two types of polymers are also different, suggesting different polymerization mechanisms. The results can be simply explained by the heterogeneous distributions of reactants in the system. This study is helpful to better understand surface-initiated polymerization.

关键词： Surface-initiated polymerization Polymer brush Stochastic reaction model Heterogeneous polymerization Simultaneous polymerization

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Experimental and numerical simulation study on the erosion behavior of the elbow of gathering pipeline in shale gas field

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Petroleum Science 2024年第2期21卷 1257-1274页

作者： En-Bin Liu shen Huang Ding-Chao Tian Lai-Min Shi shan-Bi Peng He Zheng Petroleum Engineering School Southwest Petroleum UniversityChengdu 610500SichuanChina Chongqing Natural Gas Sales Center Natural Gas BranchSinopecChongqing400023China Zhejiang Zheneng Natural Gas Operation Co. Ltd.Hangzhou 310000ZhejiangChina School of Civil Engineering and Architecture Southwest Petroleum UniversityChengdu 610500SichuanChina Louisiana Tech Univ Trenchless Technol Ctr599 Dan Reneau DrRustonLA71270USA Southwest Oil and Gas Field Branch Natural Gas Research Institute Chengdu 610213SichuanChina

During the production period of shale gas, proppant particles and rock debris are produced together,which will seriously erode the elbows of gathering pipelines. In response to this problem, this paper takes the elbow of the gathering pipeline in the Changning Shale Gas Field as an example to test the erosion rate and material removal mechanism of the test piece at different angles of the elbow through experiments and compares the four erosion models with the experimental results. Through analysis, it is found that the best prediction model for quartz sand-carbon steel erosion is the Oka model. Based on the Oka model, FLUENT software was used to simulate and analyze the law of erosion of the elbow of the gas gathering pipeline under different gas flow velocities, gas gathering pressure, particle size, length of L1,and bending directions of the elbow. And a spiral pipeline structure is proposed to reduce the erosion rate of the elbow under the same working conditions. The results show that this structure can reduce erosion by 34%.

关键词： Shale gas Gas gathering pipeline Elbow Erosion CFD

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A General Authentication and Key Agreement Framework for Industrial Control System

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Chinese Journal of Electronics 2024年第4期33卷 1046-1062页

作者： shan GAO Junjie CHEN Bingsheng ZHANG Kui REN Xiaohua YE Yongsheng shen School of Cyber Science and Technology Zhejiang University Hangzhou Global Scientific and Technological Innovation Center Zhejiang University Zhejiang Provincial Key Laboratory of Blockchain and Cyberspace Governance Hangzhou City Brain Co. Ltd

In modern industrial control systems(ICSs), when user retrieving the data stored in field device like smart sensor, there exists two main problems: one is lack of the verification for identification of user and field device;the other is that user and field device need exchange a key to encrypt sensitive data transmitted over the *** propose a comprehensive authentication and key agreement framework that enables all connected devices in an ICS to mutually authenticate each other and establish a peer-to-peer session key. The framework combines two types of protocols for authentication and session key agreement: The first one is an asymmetric cryptographic key agreement protocol based on transport layer security handshake protocol used for Internet access, while the second one is a newly designed lightweight symmetric cryptographic key agreement protocol specifically for field devices. This proposed lightweight protocol imposes very light computational load and merely employs simple operations like one-way hash function and exclusive-or(XOR) operation. In comparison to other lightweight protocols, our protocol requires the field device to perform fewer computational operations during the authentication phase. The simulation results obtained using Open SSL demonstrates that each authentication and key agreement process in the lightweight protocol requires only 0.005 ms. Our lightweight key agreement protocol satisfies several essential security features, including session key secrecy, identity anonymity, untraceability, integrity, forward secrecy, and mutual authentication. It is capable of resisting impersonation, man-in-the-middle, and replay attacks. We have employed the Gong-NeedhamYahalom(GNY) logic and automated validation of Internet security protocols and application tool to verify the security of our symmetric cryptographic key agreement protocol.

关键词： Performance evaluation Protocols Costs Industrial control Internet security Authentication Time measurement

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