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Energy analysis for damage and catastrophic failure of rocks

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Science china(Technological Sciences) 2011年第S1期54卷 199-209页

作者： XIE HePing 1,2.LI LiYun 2.1,JU Yang 2.PENG RuiDong 2.& YANG YongMing 2.1 Sichuan University,Chengdu 610065,china 2.State key {2. of Coal Resources and Safe Mining,beijing key {2. of Fracture and Damage Mechanics of Rock and Concrete,china University of Mining and Technology,beijing 100083.china Sichuan University Chengdu China State key laboratory of Coal Resources and Safe Mining Beijing Key Laboratory of Fracture and Damage Mechanics of Rock and Concrete China University of Mining and Technology Beijing China

The development history and current state of studies on the characteristics and mechanisms of deformation and failure of rock materials were briefly reviewed from the viewpoint of *** main scope and the achievable objectives of the energy-based research system were *** was validated by experiments that the damage process of rocks can be well described by the rock damage evolution equation established based on energy *** was found from the uniaxial compression and biaxial compression tests that only a small proportion of the total input energy in hard rocks is dissipated before peak load and a large proportion in soft rocks is dissipated before peak *** both hard and soft rocks,the energy dissipated after peak load accounts for a greater *** energy would be required for rock failure under equal biaxial compression than under unequal biaxial *** total absorbed energy is different for rock failure under high-rate loading and low-rate *** fragmented failure pattern usually corresponds to higher energy *** mesoscopic analysis on the damage and failure of bedded salt rocks showed that the energy dissipation is prominent and the total absorbed energy for rock failure is low when cracks propagate in the weak mud interlayer while it is contrary when cracks propagate in the salt *** energy accumulation,transfer,dissipation and release during the failure process of tunnel with impending failure under disturbance were analyzed theoretically based on the elastoplastic mechanics ***,the spatial distribution of energy dissipation and energy release of fractured rocks under unloading was simulated *** was demonstrated that energy is likely to be released from the weakest surface under compression,which triggers the global failure of rocks.

关键词： rock deformation failure energy accumulation energy dissipation energy release

Preliminary study on the origin identification of natural gas by the parameters of light hydrocarbon

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Science china Earth Sciences 2008年第S1期51卷 131-139页

作者： HU GuoYi 1,2.3 ,LI Jian 1,2.,LI Jin 1,2.,LI ZhiSheng 1,2.,LUO Xia 1,2.,SUN QingWu 1,2.&MA ChengHua 1,2.1 Research Institute of Petroleum Exploration and Development(Langfang Branch),petrochina,Langfang 065007,china 2.The {2. laboratory of gas Formation and Development,petrochina,Langfang 065007,china 3 College of Geo-Resources and Information,china University of Petroleum,beijing 102.00,china Research Institute of Petroleum Exploration and Development (Langfang Branch) Petrochina Langfang China The key laboratory of {2. Formation and Development Petrochina Langfang China College of Geo-Resources and Information China University of Petroleum Beijing China

The light hydrocarbon composition of 2.9 natural gas samples and individual light hydrocarbon carbon isotopes of 53 natural gas samples from typical humic-sourced gas and sapropelic-sourced gas in the four basins of china have been determined and *** identification parameters for humic-sourced gas and sapropelic-sourced gas are proposed or *** differences of compound-specificδ13C value of individual light hydrocarbon between humic-sourced gas and sapropelic-sourced gas have been *** humic-sourced gas has the distribution ofδ13C benzene > -2.‰,δ13C toluene >-2.‰,δ13C cyclohexane >-2.‰andδ13C methyl cyclohexane >-2.‰,while the sapropelicsourced gas has the distribution ofδ13C benzene 2.‰,δ13C toluene 2.‰,δ13C cyclohexane 2.‰and δ13C methyl cyclohexane 2.‰.Among the components of C7 light hydrocarbon compound,such as normal heptane(nC7),methyl cyclohexane(MCH)and dimethyl cyclopentane(ΣDMCP),etc,relative contents of nC7 and MCH are influenced mainly by the source organic matter type of natural ***,it is suggested that the gas with relative content of nC7 of more than 30%and relative content of MCH of less than 70%is sapropelic-sourced gas,while gas with relative content of nC7 of less than 35%and relative content of MCH of more than 50%is humic-sourced *** components of C5-7 aliphatics, the gas with relative content of C5-7 normal alkane of more than 30%is sapropelic-sourced gas,while the gas with relative content of C5-7 normal alkane of less than 30%is humic-sourced *** paremeters have been suggested to identify humic-sourced gas and sapropelic-sourced gas.

关键词： natural gas humic-sourced gas sapropelic-sourced gas carbon isotope light hydrocarbon parameters

Density functional theory study of the reaction paths of reactions of CH3C（O）O2.radicals with HO2.in the gas phase

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Progress in Natural Science:Materials International 2006年第12期16卷 1269-1274页

作者： ZHOU Yuzhi~ 1,2., ZHANG Shaowen~1 and LI Qianshu~1**(1. State key laboratory of Explosion Science and Technology, {2. Institute of Technology, {2. 100081, china 2. {2. Institute of Education, {2. 100044, china) State key laboratory of Explosion Science and Technology Beijing Institute of Technology Beijing 100081 China beijing Institute of Education Beijing 100044 China

A DFT study on the reactions between CH_3C（O）O_2.nd HO_2.adicals has been carried out. It is suggested that both the triplet and singlet potential surfaces involve a complex mechanism with the formation of loosely bound intermediate complexes of reactants and products. The reaction prefers to occur on the triplet surface to produce peracetic acid (CH_3C（O）O_2.) and triplet O_2.olecule. The CH_3C（O）O_2. can further convert into CH_3C（O）O and HO radicals.

关键词： acetyl peroxy radicals HO2.radicals reaction mechanism DFT.

The role of the catalysts with highly dispersed and isolated active sites in the selective oxidation of light hydrocarbons

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Progress in Natural Science:Materials International 2005年第12期15卷 1066-1072页

作者： WANG Hongxuan and ZHAO Zhen State key laboratory of Heavy {2. Processing,china University of Petroleum,beijing 102.49,china State key laboratory of Heavy {2. Processing China University of Petroleum Beijing 102249 China

This review summarizes the role of catalysts with highly dispersed and isolated active sites (active sites:supported atoms f≤0.5 %) in the selective oxidation of light hydrocarbons,such as methane,ethane and propane,into oxygenates and the epoxidation of *** plausible structures of the highly dispersed and isolated active species,as well as their effects on the catalytic performances are *** special physico-chemical properties and the functional mechanism of the catalysts with highly dispersed and isolated active sites,as well as the preparation,characterization of the catalysts with highly dispersed and isolated active sites and their applications in other types of reactions of lower hydrocarbons are summarized.

关键词： selective oxidation light hydrocarbons highly dispersed isolated active sites oxygenates catalyst methane ethane propane

A method of identifying effective source rocks and its application in the Bozhong Depression,Bohai Sea,china

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Petroleum Science 2010年第4期7卷 458-465页

作者： Jiang Fujie Pang Xiongqi Meng Qingyang Zhou Xiaohui Basin and reservoir Research Center China University of Petroleum Beijing 102249 China State key laboratory of Petroleum Resource and Prospecting Beijing 102249 China Research Institute of Petroleum Exploration and Development PetroChina Beijing 100083 China

Research on effective source rocks directly affects the accuracy of identifying hydrocarbon resources, and indirectly affects the exploration decisions in petroliferous basins. Although the previous evaluation methods of effective source rocks vary relatively widely, a complete quantitative evaluation approach has not yet been developed. For that reason, we redefined the concept of effective source rocks based on the existing research results. Surrounding this definition, and guided by the hydrocarbon expulsion theory, the quantitative model called ＂two stages and three steps＂ method is established to predict effective source rocks. Its application in the Bozhong Depression indicates that among the four sets source rocks in the Bozhong Depression, the Member 3 of the Shahejie Formation （Es 3 ） has the largest effective source rock thickness, and the Member 1 Member 2.of the Shahejie Formation （Es 1＋2.） is the second largest .The effective part of dark mudstone is only 30%-80% of the total volume and with the increase of buried depth and improvement of quality, the effective part increases. Comprehensive analysis indicates that the ＂two stages and three steps＂ method is a practical technique for effective source rock prediction.

关键词： Source rock effectiveness hydrocarbon expulsion threshold Bozhong Depression Bohai Sea

Micro-alloying of yttrium in Zr-based bulk metallic glasses

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Progress in Natural Science:Materials International 2011年第1期21卷 46-52页

作者： Wei-jie PENG,Yong ZHANG State key laboratory for Advanced Metals and Materials, University of Science and Technology {2.,{2. 100083.china State key laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China

The effect of yttrium addition on the glass-forming ability(GFA) and mechanical properties of the Zr-based (Zr0.52.Al0.1Ti0.05Cu0.179Ni0.146)100-xYxand(Zr0.55Al0.15Ni0.1Cu0.2.100-xYx(x=0,0.2.0.4 0.6,1,2. alloys was ***-alloying of 0.6%yttrium enhances the room temperature ductility as well as the GFA of the Zr-based *** mechanism of enhancing the GFA and room temperature ductility was *** is indicated that proper yttrium addition stabilizes the undercooled liquid by means of forming lots of ordered clusters,thus improving the GFA and the room temperature ductility.

关键词： micro-alloying glass-forming ability Zr-based alloys yttrium

Recommendation Method for Contrastive Enhancement of Neighborhood Information

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Computers, Materials & Continua 2024年第1期78卷 453-472页

作者： Hairong Wang beijing Zhou Lisi Zhang He Ma School of Computer Science and Engineering North Minzu UniversityNingxia750021China

Knowledge graph can assist in improving recommendation performance and is widely applied in various person-alized recommendation ***,existing knowledge-aware recommendation methods face challenges such as weak user-item interaction supervisory signals and noise in the knowledge *** tackle these issues,this paper proposes a neighbor information contrast-enhanced recommendation method by adding subtle noise to construct contrast views and employing contrastive learning to strengthen supervisory signals and reduce knowledge ***,first,this paper adopts heterogeneous propagation and knowledge-aware attention networks to obtain multi-order neighbor embedding of users and items,mining the high-order neighbor informa-tion of users and ***,in the neighbor information,this paper introduces weak noise following a uniform distribution to construct neighbor contrast views,effectively reducing the time overhead of view *** paper then performs contrastive learning between neighbor views to promote the uniformity of view information,adjusting the neighbor structure,and achieving the goal of reducing the knowledge noise in the knowledge ***,this paper introduces multi-task learning to mitigate the problem of weak supervisory *** validate the effectiveness of our method,experiments are conducted on theMovieLens-1M,MovieLens-2.M,Book-Crossing,and Last-FM *** results showthat compared to the best baselines,our method shows significant improvements in AUC and F1.

关键词： Contrastive learning knowledge graph recommendation method

Metallogenic epoch and genesis of the gold deposits in Jiaodong Peninsula, Eastern china: a regional review

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Progress in Natural Science:Materials International 2007年第2期17卷 138-143页

作者： YANG Liqiang, DENG Jun, GE Liangsheng, WANG Qingfei, ZHANG Jing, GAO Bangfei, JIANG Shaoqing and XU Hao ( State key laboratory of Geological Processes and Mineral Resources, {2. University of Geosciences, beijing 100083. china key laboratory of Lithosphere Tectonics and Lithoprobing Technology of Ministry of Education, {2. University of Geosciences, beijing 100083. china) State key laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China key laboratory of Lithosphere Tectonics and Lithoprobing Technology MOE China University of Geosciences Beijing 100083 China

Gold deposits are characterized by multi-sources, superimposition, large scale and temporal-spatial concentration in Jiaodong Peninsula, Eastern china. In this paper, we review the history and the development of the study on metallogenic chronology and genesis of gold deposits, summarize the main features of superimposed metallogenesis, provide evidence of the Mesozoic complex metallogenic system, and point out some problems for further research of Jiaodong gold deposit cluster from a regional view. Although gold deposits are different in genetic types, ore-forming materials and geological settings, our research indicates that the accumulation and emplacement of the ore-forming materials are temporally-spatially concentrated on a large scale, and the main metallogenic epoch of Jiaodong gold deposits was concentrated in Mesozoic. Metallogenic chronology and geological-geochemical data indicate that there are two periods of gold mineralizations occurred in 130-110 Ma and 90-80 Ma respectively in Jiaodong ore cluster. The gold deposit cluster results from the superimposition of the polygenetic mineralization, and further study is needed to investigate the formation and evolution of the Mesozoic complex metallogenic system.

关键词： superimposed metallogenic system Mesozoic Jiaodong ore cluster.

Research advances in the Mesozoic tectonic regimes during the formation of Jiaodong ore cluster area

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Progress in Natural Science:Materials International 2006年第8期16卷 777-784页

作者： DENG Jun, YANG Liqiang, GE Liangsheng, WANG Qingfei, ZHANG Jing, GAO Bangfei, ZHOU Yinghua and JIANG Shaoqing (State key laboratory of Geological Processes and Mineral Resources, {2. University of Geosciences, beijing 100083. china key laboratory of Lithosphere Tectonics and Lithoprobing Technology of Ministry of Education, {2. University of Geosciences, beijing 100083. china) State key laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China key laboratory of Lithosphere Tectonics and Lithoprobing Technology of Ministry of Education China University of Geosciences Beijing 100083 China

Based on research advances of the tectonic regime in Jiaodong ore cluster area and the related tectonic regime transformation in Mesozoic era in the eastern region of North china, in this paper, we first summarize some key problems required to be studied further on. Then we suggest an approach to dealing with these problems. It is known that the gold deposits in Jiaodong ore cluster area, which are of different mineralization styles, spatial distributions and geological settings, might be as a result from one or more geologic events in Mesozoic. Till now, this kind of research on the temporal evolution and spatial migration sequence, especially on the geodynamic mechanism of the above events, is far from sufficient. Moreover, quantitatively describing the action mode and the temporal-spatial framework of tectonic dynamic regimes and formulating the relative contribution of every tectonic dynamic regime for the metallogensis are still challenges to the geologists studying on the formation of Jiaodong ore cluster area. According to the interpretation of the regional tectonic analysis, the structural dynamics, the observation and the exploration of the mineralization network, we propose a geological-physical-chemical model with some constraints originated from the comprehensive analysis. We then use this model to simulate the coupled processes of the structural deformation, thermal transport, fluid flow and the chemical reaction. The obtained results indicate that the model is efficient in further analyzing the temporal-spatial evolutional trail of the tectonic regime in Jiaodong ore cluster area and in further understanding the nature of the mass metallogensis.

关键词： tectonic regime Mesozoic era Jiaodong ore cluster area genesis metallogenic system.