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Synthesis and bioactivity of novel coumarin derivatives containing(E)-methyl 2-(methoxyimino)-2-phenylacetates

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Chinese Chemical Letters 2011年第6期22卷 663-666页

作者： Ai Ying Guan Chang ling liu Zhi Nian li ming Xing zhang State Key Laboratory of the Discovery and Development of Novel Pesticide Shenyang Research Institute of Chemical Industry Co.Ltd. Shenyang 110021China

Ten coumarin derivatives containing（E）-methyl 2-（methoxyimino）-2-phenylacetate were synthesized and *** compounds were identified by IR,~1H NMR and elemental *** test results indicated that compound 5j（R^1 is methyl and R^2 is n-C_6H_（13）） was the optimal structure in this paper with good fungicidal activity against CDM（85%） at 6.25 mg/L concentration.

关键词： Coumarins Methoxyacrylates Intermediate derivatization method Fungicides

Tertiary montane origin of the Central Asian flora,evidence inferred from cpDNA sequences of Atraphaxis(Polygonaceae)

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Journal of Integrative Plant Biology 2014年第12期56卷 1125-1135页

作者： ming-li zhang Stewart C.Sanderson Yan-Xia Sun Vyacheslav V.Byalt Xiao-li Hao Key Laboratory of Biogeography and Bioresource in Arid Land Xinjiang Institute of Ecology and Geography the Chinese Academy of Sciences Institute of Botany the Chinese Academy of Sciences Shrub Sciences Laboratory Intermountain Research Station Forest Service US Department of Agriculture Provo UT 84601 USA Wuhan Botanical Garden the Chinese Academy of Sciences Komarov Botanical Institute Russian Academy of Sciences St Petersburg RU‐197376 Russia School of life Science Shihezi University

Atraphaxis has approximately 25 species and a distribution center in Central Asia. It has been previously used to hypothesize an origin from montane forest. We sampled 18 species covering three sections within the genus and sequenced five cpDNA spacers, atpB -rbcL, psbK -psbI, psbA -trnH, rbcL, and trnL -trnF. BEAST was used to reconstruct phylogenetic relationship and time divergences, and S-DIVA and Lagrange were used, based on distribution area and ecotype data, for reconstruction of ancestral areas and events. Our results appear compatible with designation of three taxonomic sections within the genus. The generic stem and crown ages were Eocene, approximately 47 Ma, and Oligocene 27 Ma,respectively. The origin of Atraphaxis is confirmed as montane,with an ancestral area consisting of the Junggar Basin and uplands of the Pamir-Tianshan-Alatau-Altai mountain chains,and ancestral ecotype of montane forest. Two remarkable paleogeographic events, shrinkage of the inland Paratethys Sea at the boundary of the late Oligocene and early Miocene, and the time intervals of cooling and drying of global climate from24（22） Ma onward likely facilitated early diversification of Atraphaxis, while rapid uplift of the Tianshan Mountains during the late Miocene may have promoted later diversification.

关键词： Allopatric diversification Atraphaxis biogeography Central Asia flora molecular clock montane origin phylogeny Polygonaceae

Preparation of thermal barrier coatings by ultrasonic plasma spraying

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中国有色金属学会会刊：英文版 2004年第z1期14卷 92-94页

作者： WEN Xiong-wei li Lu-ming zhang Hua-tang HAO Hong-wei LU Zhi-qing Department of Mechanical Engineering Tsinghua University Beijing 100084 China Department of Mechanical Engineering Tsinghua University Beijing 100084 China Department of Mechanical Engineering Tsinghua University Beijing 100084 China Department of Mechanical Engineering Tsinghua University Beijing 100084 China Department of Mechanical Engineering Tsinghua University Beijing 100084 China

Modulated plasma arc not only can heat the powder, but also can excite ultrasonic of different frequencies and different powers. The principles and characters of the plasma arc-excited ultrasonic were described, and the ultrasonic plasma spraying was compared with normal plasma spraying. Zirconia thermal barrier coatings (TBCs) were fabricated with two kinds of method. The TBCs were studied by the optical microscope observation, SEM observation and bonding strength experiment. The results show that suitable ultrasonic changes the performance and microstructure of TBCs in evidence. And the mechanism of ultrasonic influencing the TBCs was also discussed.

关键词： plasma spraying ultrasonic thermal barrier coatings

Evolutionary-assisted reinforcement learning for reservoir real-time production optimization under uncertainty

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Petroleum Science 2023年第1期20卷 261-276页

作者： Zhong-Zheng Wang Kai zhang Guo-Dong Chen Jin-Ding zhang Wen-Dong Wang Hao-Chen Wang li-ming zhang Xia Yan Jun Yao School of Petroleum Engineering China University of PetroleumQingdao266580ShandongChina Qingdao University of Technology Qingdao266520ShandongChina The University of Hong Kong 999077Hong KongChina

Production optimization has gained increasing attention from the smart oilfield community because it can increase economic benefits and oil recovery *** existing methods could produce high-optimality results,they cannot be applied to real-time optimization for large-scale reservoirs due to high computational *** addition,most methods generally assume that the reservoir model is deterministic and ignore the uncertainty of the subsurface environment,making the obtained scheme unreliable for practical *** this work,an efficient and robust method,namely evolutionaryassisted reinforcement learning(EARL),is proposed to achieve real-time production optimization under ***,the production optimization problem is modeled as a Markov decision process in which a reinforcement learning agent interacts with the reservoir simulator to train a control policy that maximizes the specified *** deal with the problems of brittle convergence properties and lack of efficient exploration strategies of reinforcement learning approaches,a population-based evolutionary algorithm is introduced to assist the training of agents,which provides diverse exploration experiences and promotes stability and robustness due to its inherent *** with prior methods that only optimize a solution for a particular scenario,the proposed approach trains a policy that can adapt to uncertain environments and make real-time decisions to cope with unknown *** trained policy,represented by a deep convolutional neural network,can adaptively adjust the well controls based on different reservoir *** results on two reservoir models show that the proposed approach not only outperforms the RL and EA methods in terms of optimization efficiency but also has strong robustness and real-time decision capacity.

关键词： Production optimization Deep reinforcement learning Evolutionary algorithm Real-time optimization Optimization under uncertainty

Numerical optimization on differential adjusting measures for asymmetrical degenerated warm permafrost railway embankment

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Advances in Climate Change Research 2023年第3期14卷 479-491页

作者： Yan-Dong HOU Wen-Yuan LEI Shu-Hao liANG ming-li zhang Feng-Xi ZHOU School of Civil Engineering Lanzhou University of TechnologyLanzhou 730050China Key Laboratory of Disaster Prevention and Mitigation in Civil Engineering of Gansu Province Lanzhou University of TechnologyLanzhou 730050China

Affected by climate warming and shady–sunny slope effect,the permafrost foundation under the railway is undergoing a significant asymmetric degradation process;research on the corresponding regulating or strengthening measures is urgently *** on a well developed of numerical model,we analyzed the‘thermal repair’effect of three redesigned differential thermal reinforcement on the partially degraded permafrost embankment with *** results show that,when used as a strengthening measure,the method of laying crushed rock revetment(CRR)with different thicknesses on the sunny and shady slopes cannot completely eliminate the residual warm permafrost regions formed in the previous thermal *** the TCRR scheme is adopted for reinforcement,although horizontal region from the evaporation section of thermosyphones(TPCTs)to the right side of the embankment is remarkably cooled,permafrost under the sunny slope is still *** the long run,both ETCRR and TCECRR reinforcement schemes can produce a large range of‘cold core’right below the whole ***,from the perspective of the simultaneous functioning range and cold storage capacity,the TCECRR scheme is signally more *** thermal insulation materials in the above composite strengthening measures can not only resist the heat input in the warm season,but also improve their working efficiency by maintaining the temperature difference between the evaporation section of the heat pipe and the external environment in cold *** addition of crushed rock revetment in TCECRR has played its thermal semiconductor effect and further improved the comprehensive thermal repair efficiency of the composite measures.

关键词： Asymmetric degradation Crushed rock revetment Thermal insulation materials TPCT Reinforcement

The application of event-tree based approach in long-term crude oil scheduling

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Science China Chemistry 2010年第6期53卷 1445-1452页

作者： ZOU LaiXi,li ChuFu,zhang ming & HE XiaoRong Department of Chemical Engineering,Tsinghua University,Beijing 100084,China 1. Department of Chemical Engineering Tsinghua University Beijing 100084 China

This paper addresses the problem of optimal operation in long-term crude oil scheduling,which involves unloading crude oil from vessels,transferring it to charging tanks and feeding it to the distillation *** application of a new approach for modeling and optimization of long-term crude oil scheduling is presented and the event-tree based modeling method that is very different from mathematical programming is *** approach is developed on the basis of natural language modeling and continuous time *** triggered rules,decomposition strategy,depth-first search algorithm and pruning strategy are adopted to improve the efficiency of searching the optimum *** approach is successfully applied to an industrial-size problem over a horizon of 4 weeks,involving 7 vessels,6 storage tanks,6 charging tanks,2 crude oil distillation units,and 6 crude oil *** CPU (AMD 3000+,2.0GHz) solving time is less than 70 seconds.

关键词： crude oil scheduling modeling and optimization event-tree based depth-first search algorithm

THE QIONGHAI CRUSTAL TILT OBSERVATION SYSTEM AND THE SEISMIC ACTIVITY IN WESTERN SICHUAN PROVINCE, CHINA

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地震地质 1990年第2期 115-120页

作者： zhang Chong-li, zhang Cun-de Xiang Jia-cui, li Tie-ming and zhang Da-wei(Institute of Geology, State Seismological Bureau)

In this paper, we introduce the measurements of crustal tilt using the Qionghai Observation System and a preliminary approach to the relation between the crustal plane tilt observed by the System and seismic activity in the region around the Qionghai Lake, at *** results show that the observed accuracy may reach the magnitude of 10-7-10-8 radian. The processes of the crustal stress accumulation and release are characterized by the activity of moderate earthquakes (M≥5.0) whose epicenters are located within a range away from the Qionghai Lake, and are reflected to a certain extent by time dependent processes of the crustal tilt observed by the *** short- term and impending precursors of moderate earthquakes are similar to those of the great ones, featuring of trending and abrupt anomalies.

关键词： Crustal deformation Xichang Qionghai Seismic activity

Preparation and Structural Characterization of Polystyrene-Rectorite Nanocomposites

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Wuhan University Journal of Natural Sciences 2003年第03A期8卷 817-820页

作者： Fang Peng\|fei, liu li\|ming, zhang ming, zhang Shao\|ping, Wang Bo, Wang Shao\|jie School of Physics and Technology, Wuhan University, Wuhan 430072, Hubei,China Wuhan University

The polystyrene/rectorite nanocomposites were prepared by free radical polymerization of styrene containing dispersed organophilic rectorite. The structures and thermal properties of these hybrids have been investigated by X\|ray diffraction (XRD), fourier transform infrared (FT\|IR), positron annihilation spectroscopy (PAS) and thermal gravimetric analysis (TGA) techniques. It was found that exfoliation of rectorite in polystyrene (PS) matrix was achieved. The average free\|volume radius in the PS/clay nanocomposites is generally same as that in PS. Along with increment of rectorite contents, the interface between rectorite and polystyrene matrix increases, and the free\|volume concentration decreases obviously. And the polystyrene nanocomposites have higher thermal decomposition temperature than pure PS.

关键词： polystyrene rectorite nanocomposites positron annihilation spectroscopy

Better use of experience from other reservoirs for accurate production forecasting by learn-to-learn method

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Petroleum Science 2024年第1期21卷 716-728页

作者： Hao-Chen Wang Kai zhang Nancy Chen Wen-Sheng Zhou Chen liu Ji-Fu Wang li-ming zhang Zhi-Gang Yu Shi-Ti Cui Mei-Chun Yang China University of Petroleum(East China) 66 Changjiang West RoadQingdao West Coast New AreaQingdao266580ShandongChina University of Calgary 2500 University Dr NWCalgaryT2N 1N4AlbertaCanada Qingdao University of Technology Qingdao266071ShandongChina State Key Laboratory of Offshore Oil Exploitation Beijing100028China CNOOC Research Institute Ltd. Beijing100028China CNPC Tarim Oilfield Branch Company Korla841000XinjiangChina National Engineering Laboratory for Exploration and Development of Low-Permeability Oil and Gas Fields Xi'an710000ShaanxiChina Sinopec Matrix Co. LTDQingdao266000ShandongChina

To assess whether a development strategy will be profitable enough,production forecasting is a crucial and difficult step in the *** development history of other reservoirs in the same class tends to be studied to make predictions ***,the permeability field,well patterns,and development regime must all be similar for two reservoirs to be considered in the same *** results in very few available experiences from other reservoirs even though there is a lot of historical information on numerous reservoirs because it is difficult to find such similar *** paper proposes a learn-to-learn method,which can better utilize a vast amount of historical data from various ***,the proposed method first learns how to learn samples before directly learning rules in ***,by utilizing gradients from networks with independent parameters and copied structure in each class of reservoirs,the proposed network obtains the optimal shared initial parameters which are regarded as transferable information across different *** on that,the network is able to predict future production indices for the target reservoir by only training with very limited samples collected from reservoirs in the same *** cases further demonstrate its superiority in accuracy to other widely-used network methods.

关键词： Production forecasting Multiple patterns Few-shot learning Transfer learning