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Progress in the application of graphene material in oilfield chemistry:A review

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Petroleum 2024年第2期10卷 175-190页

作者： Jinsheng Sun Yuanwei Sun Yong Lai Li Li Gang Yang Kaihe Lv Taifeng Zhang Xianfa Zhang Zonglun Wang Zhe Xu zhiwen dai Jingping Liu School of Petroleum Engineering China University of Petroleum (East China) CNPC Engineering Technology R&D Company Limited Nanchong Vocational and Technical College Oil & Gas Technology Research Institute of Changqing Oilfield Company CNPC Greatwall Drilling Fluids Company

Graphene is a single atom thick crystal composed of carbon atoms. It is the lightest, thinnest, strongest material that conducts heat and electricity well heretofore. In terms of application, by introducing oxygen-containing groups, graphene can be well dispersed in solvents, can be chemically modified and functionalized, or connected with other electroactive substances through covalent bond or non-covalent bond to form composite materials, which is conducive to further processing and promotion. The application of graphene in oilfield chemistry started late, but developed rapidly. Graphene has played an active role in drilling fluid, cementing fluid, fracturing fluid, displacement fluid and other oilfield working fluids. It can enhance the temperature and salt resistance of working fluid and improve the effect of working fluid. In this paper, several directions of graphene applications in oilfield chemistry, such as modified graphene, graphene copolymers and graphene nanoparticles, are reviewed in detail from the synthesis methods, action mechanisms and effects of graphene and its derivatives, and the frontier cases at this stage are given. On the basis of the existing research, suggestions for the development direction of graphene materials in oilfield chemistry are given for a variety of graphene materials, aiming to provide guidance for the application of graphene in oilfield chemistry.

关键词： Oilfield chemistry Graphene Action mechanism Application Prospect

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网联车辆编队的信号灯路口通行控制策略

现代制造工程 2024年第1期 118-123页

作者：孔慧芳戴志文合肥工业大学电气与自动化工程学院合肥230009

为提高信号灯路口场景下车辆编队的安全性和通行效率,提出V2X环境下网联车辆编队的信号灯路口通行控制策略。在信号灯路口上游设置一段控制区,以车辆编队领航车在信号灯路口排队疏散后到达信号灯路口为目标,对进入控制区的车辆编队速度... 详细信息

为提高信号灯路口场景下车辆编队的安全性和通行效率,提出V2X环境下网联车辆编队的信号灯路口通行控制策略。在信号灯路口上游设置一段控制区,以车辆编队领航车在信号灯路口排队疏散后到达信号灯路口为目标,对进入控制区的车辆编队速度进行优化。考虑速度变化对车辆编队纵向安全距离的影响,引入分布式模型预测控制理论,建立固定跟车时距控制策略下编队车辆的速度跟随控制模型,并采用加权二次型性能泛函将速度跟随控制问题转化为易于在线求解的凸二次规划问题。通过PreScan/Simulink软件仿真将信号灯路口通行控制策略与固定跟车时距控制策略进行对比,以验证速度跟随控制模型的有效性,结果表明:信号灯路口通行控制策略能够避免车辆间碰撞冲突,并可以减少编队车辆在信号灯路口的通行耗时,在保证安全性的同时提高了通行效率。

关键词：智能网联汽车信号灯路口车辆编队控制车路协同模型预测控制

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国际快堆发展综述

原子能科学技术 2024年第S02期58卷 265-270页

作者：张东辉王松平代智文中核霞浦核电有限公司福建宁德352000

快堆着眼于铀资源的高效利用和放射性废物最小化管理,是核能发展的高阶阶段。因此,在第4代核能系统的6种堆型中,有3种是快堆。在历经多年发展之后,从全球来看,快堆中的钠冷快堆已完整走过实验堆、原型堆和示范堆,系统性解决了技术和配... 详细信息

快堆着眼于铀资源的高效利用和放射性废物最小化管理,是核能发展的高阶阶段。因此,在第4代核能系统的6种堆型中,有3种是快堆。在历经多年发展之后,从全球来看,快堆中的钠冷快堆已完整走过实验堆、原型堆和示范堆,系统性解决了技术和配套体系问题,其工程化水平已处于商业化前夜。快堆规模化推广,将打破核能发展的天花板,238U的利用使得核能总资源量达到全球已知化石能源总和的5.6倍,可以在千年尺度上解决全球能源问题。同时,快堆的推广也将为清洁能源体系的建立、双碳目标的实现打下坚实基础。本文综述了国际快堆技术的发展概况,提出第4代核能系统——快堆在安全性、可持续性、经济性和核燃料循环体系建立等方面面临的技术挑战与突破,并指出快堆未来的发展趋势。

关键词：快堆清洁能源双碳第4代核能系统

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钠冷快堆制氢工艺及经济性研究

原子能科学技术 2024年第5期58卷 1101-1108页

作者：代智文张东辉王松平邢成文中核霞浦核电有限公司福建宁德352000

“双碳”目标下,氢能将成为未来能源体系的重要组成部分。钠冷快堆具有反应堆出口温度高、热效率高等优点,可同时提供大规模制氢所需的电力和热能。本文对钠冷快堆匹配制氢工艺进行研究,研究显示在零碳排放目标下匹配的制氢工艺为铜-氯... 详细信息

“双碳”目标下,氢能将成为未来能源体系的重要组成部分。钠冷快堆具有反应堆出口温度高、热效率高等优点,可同时提供大规模制氢所需的电力和热能。本文对钠冷快堆匹配制氢工艺进行研究,研究显示在零碳排放目标下匹配的制氢工艺为铜-氯热化学循环制氢与常规电解制氢。利用国际原子能机构开发的制氢经济评价程序HEEP对百万千瓦快堆(CFR1000)耦合常规电解、热化学循环制氢成本进行了经济性分析,并基于GIF开发的四代堆经济评价软件G4-ECONS V3.0校核验证。计算结果显示,CFR1000耦合常规电解制氢成本为3.05美元/kg,耦合热化学循环热电联产的制氢成本为4.83美元/kg。钠冷快堆投资比将随着未来规模化建造后逐渐降低,利用钠冷快堆制氢具有广阔的应用前景。

关键词：核能制氢经济性分析钠冷快堆

Finite-Time Stabilization for Constrained Discrete-time Systems by Using Model Predictive Control

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IEEE/CAA Journal of Automatica Sinica 2024年第7期11卷 1656-1666页

作者： Bing Zhu Xiaozhuoer Yuan Li dai zhiwen Qiang IEEE the Seventh Research Division Beihang UniversityBeijing 100191China the School of Automation Beijing Institute of TechnologyBeijing 100081China

In this paper, a model predictive control(MPC)framework is proposed for finite-time stabilization of linear and nonlinear discrete-time systems subject to state and control constraints. The proposed MPC framework guarantees the finite-time convergence property by assigning the control horizon equal to the dimension of the overall system, and only penalizing the terminal cost in the optimization, where the stage costs are not penalized explicitly. A terminal inequality constraint is added to guarantee the feasibility and stability of the closed-loop *** feasibility can be improved via augmentation. The finite-time convergence of the proposed MPC is proved theoretically,and is supported by simulation examples.

关键词： Constraints deadbeat control finite-time stabilization model predictive control(MPC)

Development and performance evaluation of a high temperature resistant, internal rigid, and external flexible plugging agent for water-based drilling fluids

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Petroleum 2023年第1期9卷 33-40页

作者： Zhe Xu Jinsheng Sun Li Li Kaihe Lv Jingping Liu zhiwen dai Xianfa Zhang Zonglun Wang School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580China CNPC Engineering Technology R&D Company Limited Changping10206China Oil&Gas Technology Research Institute of Changqing Oilfield Company Xi'an710000China

During the drilling process for oil and gas production,a larger number of drilling fluids invade the formation,causing severe formation damage and wellbore collapsing,which seriously hinders the efficient production of deep oil and *** several plugging agents have been developed for efficient fracture sealing in recent years,the development of high-performance plugging agents with self-adaptive ability and high-temperature resistance remain a ***,we report the synthesis of an internal rigid and external flexible plugging agent PANS by reversed-phase emulsion polymerization with nano-silica as the rigid core and poly(acrylamide-co-N-vinylpyrrolidone)as a flexible *** plugging agent has a median particle size of 10.5μm and can self-adapt to seal the microfractures and fractures in the formation,leading to an effective reduction in the filtration loss of bentonite water-based drilling fluid under both low temperature and low pressure(LTLP)and high temperature and high pressure(HTHP)*** addition,compared with the neat nano-silica(500 nm),the sealing efficiency of PANS toward 100–120 mesh sand bed was increased by 71.4%after hot rolling at 180°C.

关键词： Internal rigidity External flexibility Plugging agent Filter loss reduction Plugging performance

RL and AHP-Based Multi-Timescale Multi-Clock Source Time Synchronization for Distribution Power Internet of Things

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Computers, Materials & Continua 2024年第3期78卷 4453-4469页

作者： Jiangang Lu Ruifeng Zhao zhiwen Yu Yue dai Kaiwen Zeng Electric Power Dispatching and Control Center Guangdong Power Grid Co.Ltd.Guangzhou510600China

Time synchronization(TS)is crucial for ensuring the secure and reliable functioning of the distribution power Internet of Things(IoT).Multi-clock source time synchronization(MTS)has significant advantages of high reliability and accuracy but still faces challenges such as optimization of the multi-clock source selection and the clock source weight calculation at different timescales,and the coupling of synchronization latency jitter and pulse phase *** this paper,the multi-timescale MTS model is conducted,and the reinforcement learning(RL)and analytic hierarchy process(AHP)-based multi-timescale MTS algorithm is designed to improve the weighted summation of synchronization latency jitter standard deviation and average pulse phase ***,the multi-clock source selection is optimized based on Softmax in the large timescale,and the clock source weight calculation is optimized based on lower confidence bound-assisted AHP in the small *** shows that the proposed algorithm can effectively reduce time synchronization delay standard deviation and average pulse phase difference.

关键词： Multi-clock source time synchronization(TS) power Internet of Things reinforcement learning analytic hierarchy process

Effect of electroacupuncture at Neiguan(PC6)at different time points on myocardial ischemia reperfusion arrhythmia in rats

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Journal of Traditional Chinese Medicine 2024年第1期44卷 113-121页

作者： SUN Qianhui CHENG Kai dai Xingye YANG zhiwen WU Xiaoling XU Chang QIU Xinghua GAO Xiaofeng LIU Daonan YANG Qirui School of Acupuncture and Tuina Beijing University of Chinese MedicineBeijing 100029China Beijing MedEx Technology Co. Ltd.Beijing 100029China

OBJECTIVE:To observe the effects of electroacupuncture at Neiguan(PC6)at different time points on reperfusion arrhythmia(RA)after myocardial ischemia and reperfusion in rats,and to investigate the correlation of this protective effect with nerve growth factor(NGF),tyrosine kinase A(Trk A),tyrosine hydroxylase(TH),and norepinephrine(NE).METHODS:A total of 72 Sprague-Dawley male rats were randomly divided into six groups(n=12 rats/group):normal group(Norm),sham operation group(Sham),ischemia reperfusion group(I/R),pre-ischemic electroacupuncture group(EAI),pre-reperfusion electroacupuncture group(EAII),post-reperfusion electroacupuncture group(EAIII).The myocardial ischemia-reperfusion injury(MIRI)model was induced by occlusion of left anterior descending coronary artery for 20 min followed by reperfusion for 40 min in *** no intervention in the Norm group and only threading without ligation in the Sham *** pretreatment at 20 min/d for 7 d before ligation in the EAⅠgroup,20 min of electroacupuncture before reperfusion in the EAII group and 20 min of electroacupuncture after reperfusion in the EAIII *** electrocardiogram(ECG)of each group was recorded throughout the whole process,and the success of the MIRI model was determined based on the changs of J-point and T-wave in the *** arrhythmia score was used to record premature ventricular contractions,ventricular tachycardia and ventricular fibrillation during the reperfusion period to assess the reperfusion induced *** expression levels of NGF,Trk A,TH protein were measured by Western ***,the expression levels of plasma and myocardial NE levels were detected by enzyme linked immunosorbent ***:The differences between Norm group and Sham group were not statistically significant in all *** score,myocardial NGF,Trk A,TH,and NE expression were significantly higher in the I/R group compared with the Sham *** score,myocardial NGF,T

关键词： myocardial reperfusion injury reperfusion arrhythmia electroacupuncture point PC6(Neiguan) nerve growth factor protein-tyrosine kinases norepinephrine

Low-Complexity Integrated Super-Resolution Sensing and Communication with Signal Decimation and Ambiguity Removal

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ZTE Communications 2024年

作者： dai Qianglong ZHOU zhiwen XIAO Zhiqiang ZENG Yong YANG Fei CHEN Yan National Mobile Communications Research Laboratory， Southeast University Purple Mountain Laboratories Wireless Technology Lab.， 2012 Lab， Shanghai Huawei Technologies Co.， Ltd

Integrated sensing and communication (ISAC) is one of the main usage scenarios for the sixth-generation (6G) wireless networks. To most efficiently utilize the limited wireless resources， integrated super-resolution sensing and communication (ISSAC) has been recently proposed to significantly improve sensing performance with super-resolution algorithms for ISAC systems， such as the Multiple Signal Classification (MUSIC) algorithm. However， traditional super-resolution sensing algorithms suffer from prohibitive computational complexity for orthogonal-frequency division multiplexing (OFDM) systems due to the large dimensions of the signals in the subcarrier and symbol domains. To address such issues， we propose a novel two-stage approach to significantly reduce the computational complexity for super-resolution range estimation. The key idea of the proposed scheme is to first uniformly decimate signals in the subcarrier domain， so that the computational complexity is significantly reduced without missing any target in the range domain. However， the decimation operation may result in range ambiguity due to pseudo peaks， which is addressed by the second stage where the total collocated subcarrier data are used for verification of the detected peaks. Compared with traditional MUSIC algorithms， the proposed scheme reduces computational complexity by two orders of magnitude， while maintaining the range resolution and unambiguity. Simulation results verify the effectiveness of the proposed scheme.

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