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CO_(2),N_(2),and CO_(2)/N_(2)mixed gas injection for enhanced shale gas recovery and CO_(2)geological storage

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Frontiers in Energy 2023年第3期17卷 428-445页

作者： Jianfa WU Haoran HU Cheng CHANG Deliang zhang Jian zhang Shengxian ZHAO Bo WANG Qiushi zhang Yiming CHEN Fanhua ZENG Shale Gas Research Institute Petro-China Southwest Oil and Gas-field CompanyChengdu 610051China Faculty of Engineering and Applied Science University of ReginaSK S4S 0A2Canada Department of Petroleum and Natural Gas Engineering Liaoning Petrochemical UniversityFushun 113001China

In this work,using fractured shale cores,isothermal adsorption experiments and core flooding tests were conducted to investigate the performance of injecting different gases to enhance shale gas recovery and CO_(2)geological storage efficiency under real reservoir *** adsorption process of shale to different gases was in agreement with the extended-Langmuir model,and the adsorption capacity of CO_(2)was the largest,followed by CH_(4),and that of N_(2)was the smallest of the three pure *** addition,when the CO_(2)concentration in the mixed gas exceeded 50%,the adsorption capacity of the mixed gas was greater than that of CH4,and had a strong competitive adsorption *** the core flooding tests,pure gas injection showed that the breakthrough time of CO_(2)was longer than that of N_(2),and the CH_(4)recovery factor at the breakthrough time(Rch,)was also higher than that of N_(2).The RcH of CO_(2)gas injection was approximately 44.09%,while the RcH,of N_(2)was only 31.63%.For CO_(2)/N_(2)mixed gas injection,with the increase of CO_(2)concentration,the RcH,increased,and the RcH,for mixed gas CO_(2)/N_(2)=8:2 was close to that of pure CO_(2),about 40.24%.Moreover,the breakthrough time of N_(2)in mixed gas was not much different from that when pure N_(2)was injected,while the breakthrough time of CO_(2)was prolonged,which indicated that with the increase of N_(2)concentration in the mixed gas,the breakthrough time of CO_(2)could be ***,an abnormal surge of N_(2)concentration in the produced gas was observed after N_(2)*** regards to CO_(2)storage efficiency(S_(Storage-CO_(2)),as the CO_(2)concentration increased,S storage-co_(2)also *** S storage-co_(2),of the pure CO_(2)gas injection was about 35.96%,while for mixed gas CO_(2)/N_(2)=8:2,S sorage-co,was about 32.28%.

关键词： shale gas gas injection competitive adsorption enhanced shale gas recovery CO_(2)geological storage

Effective Stacking Fault Energy in Face-Centered Cubic Metals

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Acta Metallurgica Sinica(English Letters) 2018年第8期31卷 873-877页

作者： Ke-Qiang Li Zhen-Jun zhang Lin-Lin Li Peng zhang Jin-Bo Yang Zhe-Feng zhang Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences School of Materials Science and Engineering University of Science and Technology of China

As a typical configuration in plastic deformations, dislocation arrays possess a large variation of the separation of the partial dislocation pairs in face-centered cubic（fcc） metals. This can be manifested conveniently by an effective stacking fault energy（SFE）. The effective SFE of dislocation arrays is described within the elastic theory of dislocations and verified by atomistic simulations. The atomistic modeling results reveal that the general formulae of the effective SFE can give a reasonably satisfactory prediction for all dislocation types, especially for edge dislocation arrays. Furthermore, the predicted variation of the effective SFE is consistent with several previous experiments, in which the measured SFE is not definite, changing with dislocation density. Our approach could provide better understandings of cross-slip and the competition between slip and twinning during plastic deformations in fcc metals.

关键词： Face-centered cubic Stacking fault energy - Dislocation dissociation Atomistic modeling

Microstructure evolution of extruded Mg-RE-Ag alloy during short-time heat treatment

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Journal of Rare Earths 2024年第12期42卷 2350-2361页

作者： Zehua Li Jinghuai zhang Shujuan Liu Jiaming Hao Liyuan Liu Yuying He Haodong zhang Xingkai Jiao Xiaobo zhang Ruizhi Wu Key Laboratory of Superlight Material and Surface Technology Ministry of Education College of Material Science and Chemical Engineering Harbin Engineering University School of Materials Science and Engineering Harbin Institute of Technology Jiangsu Key Laboratory of Advanced Structural Materials and Application Technology Nanjing Institute of Technology

Microstructure regulation via short-time heat treatment is conducive to the optimization in the microstructure and properties of precipitable magnesium(Mg) alloys, but there is currently a lack of relevant studies. In this work, the microstructure evolution of a Mg-RE-Ag alloy during different short-time heat treatments was characterized and discussed. The results show that extreme short-time heat treatment(ESHT, e.g., 2 min) at 450-480℃ can greatly increase solute concentration in Mg matrix through the rapid re-dissolution of the second-phase and simultaneously maintain fine grains, while the ESHT at a too high temperature(e.g., 510℃) is not suitable due to excessive grain growth and coarse second phase regenerated at grain boundaries. It is found that 480℃ is the approximate critical temperature for appropriate ESHT, and further prolongation of the time will lead to excessive grain growth. It is suggested that in addition to grain boundary migration, grain rotation is activated, resulting in the annihilation of high-angle grain boundaries with relatively low misorientation, as well as the reduction in the ability of the residual second phase to pin grain boundaries. In addition, the reasons for the abnormal grain boundary segregation and grain boundary continuous phase were analyzed from the perspective of interfacial energy. This study provides a basis for effective microstructure regulation of Mg-RE alloys.

关键词： Magnesium alloy Rare earth alloying Microstructure Heat treatment Precipitates Rare earths

Coordinated response of milk bacterial and metabolic profiles to subacute ruminal acidosis in lactating dairy cows

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Journal of Animal Science and Biotechnology 2023年第6期14卷 2483-2495页

作者： Yingyu Mu Wangpan Qi Tao zhang Jiyou zhang Shengyong Mao Ruminant Nutrition and Feed Engineering Technology Research Center College of Animal Science and TechnologyNanjing Agricultural UniversityNanjing 210095China Laboratory of Gastrointestinal Microbiology Jiangsu Key Laboratory of Gastrointestinal Nutrition and Animal HealthNational Center for International Research on Animal Gut NutritionCollege of Animal Science and TechnologyNanjing Agricultural UniversityNanjing 210095China

Background Bovine milk is an important source of nutrition for human consumption,and its quality is closely associated with the microbiota and metabolites in *** there is limited knowledge about the milk microbiome and metabolome in cows with subacute ruminal *** Eight ruminally cannulated Holstein cows in mid lactation were selected for a 3-week *** cows were randomly allocated into 2 groups,fed either a conventional diet(CON;40%concentrate;dry matter basis)or a high-concentrate diet(HC;60%concentrate;dry matter basis).Results The results showed that there was a decreased milk fat percentage in the HC group compared to the CON *** amplicon sequencing results indicated that the alpha diversity indices were not affected by the HC *** the phylum level,the milk bacteria were dominated by Proteobacteria,Actinobacteria,Bacteroidetes,and Firmicutes both in the CON and HC *** the genus level,the HC cows displayed an improved proportion of Labrys(P=0.015)compared with the CON *** of both the principal components analysis and partial least squares of discriminant analysis of milk metabolome revealed that samples of the CON and HC groups clustered separately.A total of 31 differential metabolites were identified between the two *** these,the levels of 11 metabolites decreased(α-linolenic acid,prostaglandin E2,L-lactic acid,L-malic acid,3-hydroxysebacic acid,succinyladenosine,guanosine,pyridoxal,L-glutamic acid,hippuric acid,and trigonelline),whereas the levels of the other 20 metabolites increased in the HC group with respect to the CON group(P<0.05).Conclusion These results suggested that subacute ruminal acidosis less impacted the diversity and composition of milk microbiota,but altered the milk metabolic profiles,which led to the decline of the milk quality.

关键词： High-concentrate diet Milk bacteria Milk metabolome Milk quality Subacute ruminal acidosis

A Construction Method of Arbitrary-Length Polar Codes

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China Communications 2023年第10期20卷 153-162页

作者： Xiaojun zhang Chengguan Chen Rongcai zhang Jianming Cui Qingtian Zeng Shandong University of Science and Technology Qingdao 266590China State Key Laboratory of High-End Server and Storage Technology Jinan 250101China

To remove the restriction on code length of polar codes,this paper proposes a construction scheme,called stepwise polar codes,which can gen-erate arbitrary-length polar *** stepwise polar codes are generated by sub-polar codes with different code *** improve coding performance,sub-polar codes are united by polarization effect priority algorithm,which can reduce the number of in-completely polarized ***,the construction method of the generator matrix of the stepwise po-lar code is ***,we prove that the proposed scheme has lower decoding complexity than punctured,multi-kernel polar *** results show that the proposed method can achieve similar decoding performance compared with the conventional punctured polar codes,rate-compatible punctured polar code,PC-short and asymmetric polar codes(APC)when code length N=48 and 72,respectively.

关键词： code construction polar codes arbitrary-length channel polarization union encoding

Combination method of conflict evidences based on evidence similarity

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Journal of Systems Engineering and Electronics 2017年第3期28卷 503-513页

作者： Wenhao Bi An zhang Yuan Yuan School of Aeronautics Northwestern Polytechnical UniversityXi’an 710129China

Aiming at the problem that the traditional Dempster Shafer (D-S) evidence theory cannot deal with conflicted evidences effectively and correctly, this paper points out that the key issue of this problem is to measure the degree of conflict between evidences correctly after analyzing various improved methods. The existing evidence conflict measure methods are analyzed, and a new evidence conflict measure method called evidence similarity measure based on the Tanimoto measure is proposed, while a new evidence combination method is proposed on the basis of evidence similarity measure. Firstly, the conflict degrees between evidences are obtained through the evidence similarity measure. Then the evidence sources are modified based on the credibility of different evidences and the weights of conflicted parts of evidences on different focal elements are determined. Finally, the fusion result is obtained by this method. Numerical examples show that the proposed method can effectively fuse evidences when evidences are consistent or highly conflicted, and it has a fast convergence speed, a high degree of accuracy and good adaptability.

关键词： evidence theory evidence conflict conflict measure evidence similarity information fusion

The connection of phytoplankton biomass in the Marguerite Bay polynya of the western Antarctic Peninsula to the Southern Annular Mode

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Acta Oceanologica Sinica 2024年第1期43卷 35-47页

作者： Ning Jiang Zhaoru zhang Ruifeng zhang Chuning Wang Meng Zhou School of Oceanography Shanghai Jiao Tong UniversityShanghai 200240China Key Laboratory for Polar Science Polar Research Institute of ChinaMinistry of Natural ResourcesShanghai 200136China

Antarctic coastal polynyas are biological hotspots in the Southern Ocean that support the abundance of hightrophic-level predators and are important for carbon cycling in the high-latitude *** this study,we examined the interannual variation of summertime phytoplankton biomass in the Marguerite Bay polynya(MBP)in the western Antarctic Peninsula area,and linked such variability to the Southern Annular Mode(SAM)that dominated the southern hemisphere extratropical climate *** satellite data,atmosphere reanalysis products and numerical simulations,we found that the interannual variation of summer chlorophyll-a(Chl-a)concentration in the MBP is significantly and negatively correlated with the spring SAM index,and weakly correlated with the summer SAM *** negative relation between summer Chl-a and spring SAM is due to weaker spring vertical mixing under a more positive SAM condition,which would inhibit the supply of iron from deep layers into the surface euphotic *** negative relation between spring mixing and spring SAM results from greater precipitation rate over the MBP region in positive SAM phase,which leads to lower salinity in the ocean surface *** coupled physical-biological mechanisms between SAM and phytoplankton biomass revealed in this study is important for us to predict the future variations of phytoplankton biomasses in Antarctic polynyas under climate change.

关键词： Marguerite Bay polynya phytoplankton biomass Southern Annular Mode mixed layer depth interannual variation

Design, Synthesis and Biological Activities of Novel N-Aryl-1H-pyrazole-5-carboxylate Derivatives

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Chemical Research in Chinese Universities 2020年第5期36卷 853-858页

作者： zhang Xiulan zhang Huan MA Jinlong YU Shujing LI Zhcngming College of Science Tianjin University of Science&TechnologyTianjin 300457P.R.China State Key Laboratory of Elemento-Organic Chemistry Institute of Elemento-Organic ChemistryNankai UniversityTianjin 300071P.R.China

In an attempt to search for potent fungicide,a series of novel N-ary 1-1H-pyrazole-5-carboxylate derivatives was designed and *** chemical structures were characterized by 1H NMR spectra and high reso・lution mass spectrometry(HRMS).The preliminary bioassay results indicated that some target compounds displayed better fungicidal activities against certain fungi at 50μg/mL or favorable antitumor activities at 5 μg/mL compared with chlorothalonil and 5-fluorouracil,*** structure-activity relationship demonstrated that the introduction of ester group and amide bond was favorable to the improvement of activities against Physalospora pin cola and Phytophthora capsici.

关键词： N-Aryl-1H-pyTazole-5-carboxylate Fungicidal activity Antitumor activity

Topology: a unique dimension in protein engineering

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Science China Chemistry 2018年第1期61卷 3-16页

作者： Lianjie Xu Wen-Bin zhang Key Laboratory of Polymer Chemistry & Physics of Ministry of Education Center for Soft Matter Science and EngineeringCollege of Chemistry and Molecular Engineering Peking University

Controlling protein topology has been a long standing challenge to go beyond their linear configuration defined by the translation mechanism of cellular machinery. In this mini-review, we focus on the topological diversity in proteins and review the major categories of protein topologies known to date, including branched/star proteins, circular proteins, lasso proteins, knotted proteins, and protein catenanes. The discovery of these topologically complex natural proteins and their synthetic pathways, the rational design and recombinant synthesis of artificial topological proteins and their biophysical studies, are summarized and discussed with regard to their general features and broad implications. The complexity of protein topology is recognized and the routes to diverse protein topologies are illustrated. We believe that topology engineering is an important way to modify protein properties without altemating their native sequences and shall bring in valuable dynamic features central to the creation of artificial protein machinery.

关键词： protein topology protein engineering catenane rotaxane knot lasso peptide