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石油勘探与开发 2024年第1期51卷 190-198页

作者：王强赵金洲胡永全李勇明王玉丰西南石油大学“油气藏地质及开发工程”国家重点实验室成都610500

基于多孔介质弹性理论、嵌入式离散裂缝模型及有限体积法,考虑页岩气微观渗流机制,建立适用于裂缝性页岩气储集层的渗流-地质力学全耦合模型,并提出了重复压裂时机优化方法,采用四川盆地涪陵页岩气井资料分析了重复压裂时机的影响因素... 详细信息

基于多孔介质弹性理论、嵌入式离散裂缝模型及有限体积法,考虑页岩气微观渗流机制,建立适用于裂缝性页岩气储集层的渗流-地质力学全耦合模型,并提出了重复压裂时机优化方法,采用四川盆地涪陵页岩气井资料分析了重复压裂时机的影响因素。研究表明:受地层压力衰竭影响,最大水平主应力反转面积占总面积的百分比随时间的延长先增加后减小,且距人工裂缝越近的区域,应力反转面积百分比曲线出现峰值的时间越短,最终归零(恢复到初始状态)的时间也越短。重复压裂的最佳时间受基质渗透率、初始应力差、天然裂缝逼近角的影响:基质渗透率、初始应力差越大,应力反转面积百分比曲线出现峰值、恢复到初始状态的时间越短,采取重复压裂措施的时机越早。天然裂缝逼近角越大,裂缝附近越难发生应力反转、重复压裂最佳时间越早,人工裂缝末端以远区域越易发生应力反转、重复压裂最佳时间越晚。对于基质渗透率很小的储集层,其单井产能递减快,为保证经济性,可采取关井或注气补能等措施恢复应力,提前实施重复压裂。

关键词：页岩气井渗流-地质力学全耦合模型重复压裂时机优化影响因素

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硅基陶瓷前驱体快速裂解转化研究进展

有机硅材料 2024年第3期38卷 60-68页

作者：陈楚童陈艳杰罗永明张宗波李永明徐彩虹中国科学院化学研究所中国科学院极端环境高分子材料重点实验室北京100190 中国科学院大学化学与化工学院北京100049

聚合物前驱体裂解转化法是制备陶瓷材料的重要方法之一,裂解是该工艺中不可或缺的步骤。传统的陶瓷前驱体热裂解方法存在升降温速率慢、工艺时间长、能耗高等问题。激光裂解、微波裂解、放电等离子烧结等新技术因具有升降温速率快、能... 详细信息

聚合物前驱体裂解转化法是制备陶瓷材料的重要方法之一,裂解是该工艺中不可或缺的步骤。传统的陶瓷前驱体热裂解方法存在升降温速率慢、工艺时间长、能耗高等问题。激光裂解、微波裂解、放电等离子烧结等新技术因具有升降温速率快、能量消耗低等优势,近年来受到材料领域研究者的关注。本文总结了快速裂解方法用于硅基前驱体转化陶瓷方面的研究进展,阐述了裂解新技术在高性能陶瓷材料制备中的技术优势。

关键词：陶瓷前驱体快速裂解激光裂解微波裂解

基于ANSYS-FLUENT的云南某锡矿尾砂料浆管道输送设计研究

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有色金属科学与工程 2024年第3期15卷 407-421页

作者：廉柏栋乔登攀杨天雨王俊陈剑李绍腾李勇明高博龙赣昆明理工大学国土资源工程学院昆明650093 云南锡业大屯锡矿云南红河661018 凉山矿业股份有限公司四川凉山615141

以云南某锡矿井下充填管道为对象,经流变实验获得了该矿山全尾砂流变参数,并采用布金汉方程对尾砂料浆阻力损失进行了初步计算,最后运用ANSYS-FLUENT软件进行了模拟计算,并对模拟结果进行了深入分析。结果表明,较优方案为C1,即水泥量为3... 详细信息

以云南某锡矿井下充填管道为对象,经流变实验获得了该矿山全尾砂流变参数,并采用布金汉方程对尾砂料浆阻力损失进行了初步计算,最后运用ANSYS-FLUENT软件进行了模拟计算,并对模拟结果进行了深入分析。结果表明,较优方案为C1,即水泥量为300 kg/m^(3),质量浓度为72%的尾砂料浆能够在管道内安全输送2600余米,充填流量可达110 m^(3)/h,满足了矿山井下充填制备站至各采场空区的充填需求,确保了充填系统的安全、可靠和高效运行。进一步研究分析发现,在管道内输送的尾砂料浆速度和压力存在边界层效应;管输阻力损失随尾砂料浆的屈服应力及黏度的增加而增加,并得出了阻力损失与屈服应力及黏度之间的关系表达式。本文针对充填采矿法中矿山尾砂料浆合理、安全地管道输送,制定了简便高效的计算、模拟和分析方法,为充填采矿法的实际应用提供了有益指导。

关键词：充填采矿布金汉方程 ANSYS-FLUENT模拟尾砂料浆管道输送阻力损失

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Spectroscopic Investigation of the Interaction between Human Serum Albumins and 10-Hydroxycamptothecin

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Wuhan University Journal of Natural Sciences 2009年第3期14卷 257-261页

作者： li Guizhi liU yongming College of Chemistry Yantai University Yantai 264005Shandong China

The binding reaction between 10-hydroxycamptothecin （10-HCPT） and human serum albumins （HSA） is studied by means of fluorescence spectroscopy, UV-Vis absorption spectrum, IH NMR spectrum, and molecular simulation. The results indicate that the binding reaction of 10-HCPT and HSA is a single static quenching process, and the binding equilibrium constant for 10-HCPT binding with HSA is estimated K0-4.93×10^4 L · mol-I at 25 ℃ with the molar ratio of I ： 1. The distance （r） and energy transfer efficiency（E） between donor （HSA） and acceptor （10-HCPT） are obtained as follows, r=3.51 nm; E-0.27. The enthalpy change （△Hφ） and entropy change （△Sφ） are calcu- lated at different temperatures, and the hydrophobic force and shidipole force are the functions in the reaction. The results show that 10-HCPT binds within the subdomain II A of HSA by the hydrophobic force, and the 10-OH and 20-OH of 10-HCPT bind with both residue Leu-238 of HSA and Ala 291 of HSA by hydrogen bonds.

关键词： 10-hydroxycamptothecin human serum albumins (HSA) fluorescence spectroscopy UV absorption spectroscopy 1H NMR spectrum molecular simulation

Finite automata based on quantum logic and monadic second-order quantum logic

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Science China(Information Sciences) 2010年第1期53卷 101-114页

作者： li yongming College of Computer Science, Shaanxi Normal University, Xi’an 710062, China College of Computer Science Shaanxi Normal University

We introduce monadic second-order quantum logic and prove that the behaviors of finite automata based on quantum logic are precisely the quantum languages definable with sentences of our monadic secondorder quantum logic. This generalizes Büchi’s and Elgot’s fundamental theorems to quantum logic setting. We also consider first-order quantum logic and show that star-free quantum languages and aperiodic quantum languages introduced here coincide with the first-order quantum definable ones. This generalizes Schützenberger’s fundamental theorems to quantum logic setting. The determinazation of finite automata based on quantum logic is studied by introducing the generalized subset construction method. Then the Kleene theorem in the frame of quantum logic is presented here.

关键词： quantum logic finite automaton monadic second quantum logic quantum language quantum computation Kleene theorem

Minimizing Purifi cation-Induced Defects in Single-Walled Carbon Nanotubes Gives Films with Improved Conductivity

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Nano Research 2009年第11期2卷 865-871页

作者： Yu Wang liping Huang Yunqi liu Dacheng Wei Hongliang Zhang Hisashi Kajiura yongming li Beijing National Laboratory for Molecular Sciences Key Laboratory of Organic SolidsInstitute of ChemistryChinese Academy of SciencesBeijing 100190China Materials Laboratories Sony CorporationOkataAtsugi CityKanagawa 243-0021Japan

A method for the non-destructive purification of single-walled carbon nanotubes(SWNTs)using classical coordination chemistry to remove the metal catalyst has been *** preliminary tests,the conductivity of films based on the resulting SWNTs was markedly better than that of films prepared from SWNTs purified by treatment with oxidizing acid *** transparent and conducting SWNT films have potential applications in optoelectronic devices.

关键词： Carbon nanotube film conductivity transparency coordination chemistry

Experimental study on flow heterogeneity of shale bedding fractures based on full-diameter cores

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Petroleum Exploration and Development 2023年第5期50卷 1187-1195页

作者： ZHU Juhui ZENG Jing GENG Zhoumei li yongming WANG Tengfei li Deqi PAN Yong WANG Juan Downhole Service Company of CNPC Chuanqing Drilling Engineering Company limited Chengdu 610051China State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation at Southwest Petroleum University Chengdu 610051China Yan’an Energy Service Co. Ltd.Yan’an 716099China PetroChina Zhejiang Oilfield Company Hangzhou 310023China

A self-designed full-diameter core experimental facility was used to evaluate the flow heterogeneity of bedding fractures at four radial directions under different closure pressures and injection rates,using full-diameter cores retaining original natural bedding *** distribution morphology of bedding surface affects the conductivity of bedding fractures,and the flow capacity of bedding fractures in four radial directions varies greatly with the closure pressure and injection *** rougher the fracture surface,the greater the flow capacity varies with the closure *** unsupported bedding fractures,the mean percentage error(MPE)of the conductivity in four radial directions increase gradually with the increase of the closure *** phenomenon is especially prominent in deep rock *** is indicated that the flow heterogeneity of bedding fractures tends to increase with the closure *** proppant is placed in the fracture,at a low closure pressure,due to the combined effects of self-support of rough fracture surface,proppant instability and uneven proppant placement,the flow heterogeneity is greater than that when proppant is not placed at the same closure pressure;however,with the increase of the closure pressure,the proppant becomes compact and stable,and the flow heterogeneity is mitigated gradually.

关键词： shale full-diameter core bedding fracture conductivity heterogeneity fracturing

High efficient gene targeting in rice field eel Monopterus albus by transcription activator-like effector nucleases

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Science Bulletin 2017年第3期62卷 162-164页

作者： Ke Feng Hongrui Luo yongming li Ji Chen Yaping Wang Yonghua Sun Zuoyan Zhu Wei Hu State Key Laboratory of Freshwater Ecology and Biotechnology Institute of HydrobiologyChinese Academy of SciencesWuhan 430072China University of Chinese Academy of Science Beijing 100049China

Genome editing plays an important role in the research of gene functions,gene correction and cell replacement ***,genome editing is mainly dependent on the technology of homologous recombination(HR)and embryonic stem(ES)cell lines in mammals[1].However,genome editing is severely limited by the low efficiency of HR and lack of ES cell lines in most ***,the development of zinc finger nucleases(ZFNs),

关键词：基因打靶核酸酶转录激活胚胎干细胞 ES细胞系子样黄鳝基因组

Robust adaptive fuzzy backstepping output feedback tracking control for nonlinear system with dynamic uncertainties

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Science China(Information Sciences) 2010年第2期53卷 307-324页

作者： TONG ShaoCheng & li yongming Department of Basic Mathematics, liaoning University of Technology, Jinzhou 121001, China Department of Basic Mathematics Liaoning University of Technology

In this paper, an adaptive fuzzy output feedback control approach based on backstepping design is proposed for a class of SISO strict feedback nonlinear systems with unmeasured states, nonlinear uncertainties, unmodeled dynamics, and dynamical disturbances. Fuzzy logic systems are employed to approximate the nonlinear uncertainties, and an adaptive fuzzy state observer is designed for the states estimation. By combining backstepping technique with the fuzzy adaptive control approach, a stable adaptive fuzzy output feedback robust control is constructed recursively, in which nonlinear damping terms and a dynamical signal are introduced to counteract the nonlinear uncertainties and dominate the dynamic disturbances, respectively. It is proved that the proposed adaptive fuzzy control approach guarantees that all the signals of the closed-loop system are semi-globally uniformly bounded, and the tracking error converges to a small neighborhood of the origin. Simulation studies are included to illustrate the effectiveness of the proposed approach.

关键词： nonlinear systems fuzzy control adaptive control backstepping technique adaptive state observer stability analysis