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Mechanical characteristics and reservoir stimulation mechanisms of the Gulong shale oil reservoirs, the northern Songliao Basin

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Petroleum Science 2024年第3期21卷 2023-2036页

作者： Si-wei Meng Jia-Ping Tao tian-Jiao Li Dong-Xu Li Su-Ling Wang Liu Yang xin Liu Li-Hao Liang He Liu PetroChina Research Institute of Petroleum Exploration Development Beijing100083China National Key Laboratory of Continental Shale Oil Daqing 163002HeilongjiangChina Dalian University of Technology Dalian116024LiaoningChina PetroChina Daqing Oilfield Co.Ltd. Daqing163002HeilongjiangChina Northeast Petroleum University Daqing163002HeilongjiangChina China University of Mining and Technology(Beijing) Beijing100083China

Shale oil of the Qingshankou Formation of the Gulong Sag,the northern Songliao Basin,represents the first attempt at large-scale development of pure-shale-type shale oil in *** integrating the multiscale refined reservoir characterization with macro-micro-scale mechanical testing,it is clarified that the Gulong shale is characterized by high clay mineral content,high rock plasticity,highly-developed bedding,and prominent mechanical anisotropy.A three-dimensional(3D)fracture propagation model of hydraulic fracturing was built for the Gulong shale,which fully captures the hydraulic fracture distribution pattern affected by the high bedding density,in-situ stress,and fracturing treatment *** research showed that due to influences of bedding,hydraulic fracturing in the Gulong shale forms a complex fracture morphology featuring the main fracture with multiple perpendicular branches that have different lengths(like the outdoor directional TV antenna);however,the vertical propagation of fractures is inhibited,and the fracture height is commonly less than 10 *** limited stimulated reservoir volume(SRV)is the main problem facing the fracturing stimulation of the Gulong shale *** density has vital effects on fracture morphology,so case-specific fracturing designs shall be developed for shale intervals with different bedding development *** reservoirs with welldeveloped bedding,it is suggested to properly increase the perforation cluster spacing and raise the volume and proportions of viscous fluids of the pad,so as to effectively promote vertical fracture propagation and improve reservoir stimulation *** study integrates multi-scale fine reservoir characterization and macro-micro-scale mechanical testing,as well as the construction and numerical simulation of hydraulic fracturing models for high-density layered shale reservoirs,providing a new approach and methodological framework for the fracturing research of high-density layer

关键词： Shale oil Hydraulic fracturing High bedding density Fracture propagation model

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Cutibacterium acnes in Atopic Dermatitis:Roles and Potential Therapeutic Applications

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International Journal of Dermatology and Venereology 2024年第1期7卷 12-17页

作者： tian-Ze Yu wei Li Department of Dermatology Shanghai Institute of DermatologyHuashan HospitalFudan UniversityShanghai 200040China

Atopic dermatitis(AD)is a chronic relapsing inflammatory skin *** main initiating mechanisms of AD are disruptions in the skin microbiota,dysfunction of the skin barrier,and predominantly elevated type 2 immune *** acnes(***)is a commensal bacterium that is ubiquitous and predominant in healthy skin and shows intraspecific subtype *** abundance of *** is closely related to the sebum secreted by sebaceous *** has long been considered a proinflammatory skin bacterium that drives the development of acne *** evidence indicates that *** promotes skin microbiota homeostasis and skin barrier maintenance;however,the potential role of *** in AD remains largely *** review provides the latest information on the distribution of *** and its phylotypes in healthy skin and AD as well as an overview of the possible role of *** in the pathophysiological pathways underlying ***,the review focuses on new evidence regarding the protective functions of *** and its metabolites in AD and discusses the potential for therapeutic applications.

关键词： atopic dermatitis skin microbiota probiotic therapy

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Insight into the Role of Isolated Gold Atoms-Ceria Conjunction in Catalyzing the Water-Gas Shift Reaction

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Chinese Journal of Chemistry 2024年第6期42卷 636-644页

作者： xin-Pu Fu Hui-Zhao wei-wei Wang Chun-Jiang Jia Key Laboratory for Colloid and Interface Chemistry Key Laboratory of Special Aggregated MaterialsSchool of Chemistry and Chemical EngineeringShandong UniversityJinanShandong250100 China

As the promising catalysts for the water-gas shift(WGS)reaction,the activity of Au-CeO_(2) composites is susceptible to the aggregation size and electronic state of Au *** reports were extensively focused on the discrepancy between nonmetallic Au and metallic Au nanoparticles,whereas the understanding of the authentic role of the isolated Au atoms was ***,we investigated the catalytic behavior and structural information over two types of Au/CeO_(2) catalysts,in which the predominant conjunctions were isolated Au1-CeO_(2) and Aun-CeO_(2),*** on comprehensive characterizations,particularly by in-situ Raman and in-situ DRIFTS,we found that the isolated Au atoms were responsible for enhancing the reducibility of the CeO_(2) *** CO adsorption ability on the isolated Au sites was significantly inferior to clustered Au atoms,especially at relatively high temperatures(>200°C).As a result,the boosted O vacancy on the isolated Au1-CeO_(2) conjunctions could improve the H2O activation ability for the Au-CeO_(2) catalysts and demonstrate a comparable activity to the clustered Aun-CeO_(2) *** work might deepen understanding of the catalytic function for the isolated Au1 site within Au/CeO_(2) systems while catalyzing the WGS reaction.

关键词： Isolated Au atoms Ceria-based catalysts Water-gas shift reaction Defect Adsorption

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Regulating CRISPR/Cas9 Using Streptavidin-Biotin Interactions

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Chinese Journal of Chemistry 2024年第12期42卷 1387-1393页

作者： wei Shen wei Xiong Qianqian Qi xingyu Liu Zhongpao Xie Yuanyuan Zhang Jinxuan Hou tian tian Xiang Zhou College of Chemistry and Molecular Sciences Wuhan UniversityWuhanHubei 430072China Department of Thyroid&Breast Surgery Zhongnan Hospitalof Wuhan University Wuhan Hubei43001Chin

Comprehensive Summary Currently,CRISPR/Cas9 technology has found widespread applications across various ***,the utility of CRISPR/Cas9 is encumbered by issues pertaining to its reliability and safety,primarily stemming from the uncontrolled activity of the ***,the design and development of CRISPR/Cas9 systems with controllable activity is of paramount ***,characterized by its small molecular weight,and streptavidin,distinguished by its substantial spatial steric hindrance,can be harnessed as an ideal OFF switch(termed a"bioactivity brake")due to their interaction *** this work,we present a strategy that employs the streptavidin-biotin interaction as a"brake system"for CRISPR/Cas9,effectively allowing for the shutdown of the enzymatic activity of CRISPR/Cas9.

关键词： Streptavidin-biotin CRISPR/Cas9 CRISPR-OFF Guide RNA 2'-OH acylation Gene technology DNA cleavage

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Facile Synthesis of Polyisothioureas via Alternating Copolymerization of Aziridines and Isothiocayanates

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Chinese Journal of Polymer Science 2024年第3期42卷 292-298,I0005页

作者： Hao-tian Zhang Ming-xin Niu Qi Zhang Chen-Yang Hu Xuan Pang Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Department of Materials Science and Engineering Jilin UniversityChangchun 130025China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China

Isothiourea is an important class of sulfur-containing molecules showing unique catalytic and biological activities. As such,polyisothiourea is envisioned to be an interesting type of polymer that potentially exhibits a number of interesting properties. However, there is no access to synthesizing well-defined polyisothiourea, and currently isothiourea-containing polymers are mainly prepared by immobilizing onto other polymer's side chain. Herein, we report the first facile synthesis of polyisothioureas via alternating copolymerization of aziridines and isothiocayanates. Mediated by the catalytic system of phosphazene superbases/alcohol, a broad scope of aziridines and isothiocayanates could be transformed into polyisothioureas with adjustable substitutions(11 examples). The structures of obtained polyisothioureas were fully characterized with ^(1)H-NMR, ^(13)C-NMR, and ^(1)H-^(13)C HMBC NMR. Moreover, the polyisothioureas show tunable thermal properties depending on substitutions on the isothiourea linkages. The novel structure of these polyisothioureas will enable a powerful platform for the discovery of nextgeneration functional plastics.

关键词： Polyisothioureas Alternative copolymer Aziridines Isothiocayanates

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Influence of friction-lubrication characteristics varying with rolling speed on instability of chatter and slip in cold tandem rolling process

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Journal of Iron and Steel Research(International) 2024年第4期31卷 894-908页

作者： Yan-li xin Zhi-ying Gao Bo tian Qing-dong Zhang School of Mechanical Engineering University of Science and Technology BeijingBeijing 100083China

In the high-speed cold tandem rolling process of thin plate,chatter or slip instability gives rise to the deterioration of equipment and product *** instability behavior is closely related to interfacial friction-lubrication con-dition which is generally characterized by the friction ***,with higher and higher speed requirements,the commonly used model of friction coefficient is no longer applicable and accurate.A novel approach is suggested to calculate the speed-dependent friction coefficient,in which the viscosity-pressure-temperature effects of the lubricant,surface roughness states of work rolls and rolled piece are comprehensively involved and the mixed flm lubrication theory is ***,the influences of friction coefficient on the instability of slip and chatter are investigated for a five-stand cold tandem rolling *** one side,the critical friction coefficient for each stand is determined by calculating the corresponding slip factor;on the other hand,the friction coefficient varying with rolling speed is combined with the model of theoretical critical rolling speed presented under constant friction coefficient,so that the speed threshold is ***,the stable and unstable regions corresponding to the rear three stands are individually discussed,and the technical strategies are proposed to suppress both slip and chatter frequently occurring in the actual rolling process.

关键词： Cold tandem rolling:Oil film thickness Speed-dependent friction coefficient-Slip:Chatter

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An Adaptive Program Recommendation System for Multi-User Sharing Environment

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China Communications 2024年第6期21卷 112-128页

作者： Sun Shiyun Hu Zhengying wei xin Zhou Liang School of Communications and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China

More and more accounts or devices are shared by multiple users in video applications,which makes it difficult to provide recommendation *** recommendation schemes overlook multiuser sharing scenarios,and they cannot make effective use of the mixed information generated by multi-user when exploring users’potential *** solve these problems,this paper proposes an adaptive program recommendation system for multi-user sharing ***,we first design an offline periodic identification module by building multi-user features and periodically predicting target user in future sessions,which can separate the profile of target user from mixed log ***,an online recommendation module with adaptive timevarying exploration strategy is constructed by jointly using personal information and multi-user social information provided by identification *** one hand,to learn the dynamic changes in user-interest,a time-varying linear upper confidence bound(LinUCB)based on personal information is *** the other hand,to reduce the risk of exploration,a timeinvariant LinUCB based on separated multi-user social information from one account/device is proposed to compute the quality scores of programs for each user,which is integrated into the time-varying LinUCB by cross-weighting ***,experimental results validate the efficiency of the proposed scheme.

关键词： adaptive exploitation LinUCB multiuser recommendation system

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Variation Characteristics of Root Traits of Different Alfalfa Cultivars under Saline-Alkaline Stress and their Relationship with Soil Environmental Factors

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Phyton-International Journal of Experimental Botany 2024年第1期93卷 29-43页

作者： tian-Jiao wei Guang Li Yan-Ru Cui Jiao Xie xing-Ai Gao xing Teng xin-Ying Zhao Fa-Chun Guan Zheng-wei Liang Northeast Agricultural Research Center of China Jilin Academy of Agricultural SciencesChangchun130033China Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchun130102China

Soil salinization is the main factor that threatens the growth and development of plants and limits the increase of *** is of great significance to study the key soil environmental factors affecting plant root traits to reveal the adaptation strategies of plants to saline-alkaline-stressed soil *** this study,the root biomass,root morphological parameters and root mineral nutrient content of two alfalfa cultivars with different sensitivities to alkaline stress were analyzed with black soil as the control group and the mixed saline-alkaline soil with a ratio of 7:3 between black soil and saline-alkaline soil as the saline-alkaline treatment *** the same time,the correlation analysis of soil salinity indexes,soil nutrient indexes and the activities of key enzymes involved in soil carbon,nitrogen and phosphorus cycles was carried *** results showed that compared with the control group,the pH,EC,and urease(URE)of the soil surrounding the roots of two alfalfa cultivars were significantly increased,while soil total nitrogen(TN),total phosphorus(TP),organic carbon(SOC),andα-glucosidase activity(AGC)were significantly decreased under saline-alkaline *** was no significant difference in root biomass and root morphological parameters of saline-alkaline tolerant cultivar GN under saline-alkaline *** number of root tips(RT),root surface area(RS)and root volume(RV)of AG were reduced by 61.16%,44.54%,and 45.31%,respectively,compared with control *** ratios of K^(+)/Na^(+),Ca^(2+)/Na^(+)and Mg^(2+)/Na^(+)of GN were significantly higher than those of AG(pweight(RFW)and dry weight(RDW),root length(RL),RV and RT of alfalfa were positively regulated by soil SOC and TN,but negatively regulated by soil pH,EC,and URE(p<0.01).Root Ca^(2+)/Na+ratio was significantly positively correlated with soil TN,TP and SOC(p<0.01).The absorption of Mg and Ca ions in roots is significantly negatively regulated by soilβ-glucosidase ac

关键词： Saline-alkaline stress alfalfa root traits soil environmental factors correlation analysis

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A novel interpretable multilevel wavelet decomposition deep network for actual heartbeat classification

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Science China(Technological Sciences) 2024年第6期67卷 1842-1854页

作者： JIN YanRui LI ZhiYuan tian YuanYuan wei XiaoYang LIU ChengLiang School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai200240China

Arrhythmias may lead to sudden cardiac death if not detected and treated in time.A supraventricular premature beat(SPB)and premature ventricular contraction(PVC)are important categories of arrhythmia ***,deep learning methods have been applied to the PVC/SPB heartbeats ***,most researchers have focused on time-domain information of the electrocardiogram and there has been a lack of exploration of the interpretability of the *** this study,we design an interpretable and accurate PVC/SPB recognition algorithm,called the interpretable multilevel wavelet decomposition deep network(IMWDDN).Wavelet decomposition is introduced into the deep network and the squeeze and excitation(SE)-Residual block is designed for extracting time-domain and frequency-domain ***,inspired by the idea of residual learning,we construct a novel loss function for the constant updating of the multilevel wavelet decomposition ***,the IMWDDN is evaluated on the Third China Physiological Signal Challenge Dataset and the MIT-BIH Arrhythmia *** comparison results show IMWDDN has better detection performance with 98.51%accuracy and a 93.75%F1-macro on average,and its areas of concern are similar to those of an expert diagnosis to a certain ***,the IMWDDN has good application value in the clinical screening of PVC/SPB heartbeats.

关键词： actual heartbeat classification electrocardiogram interpretable deep network multilevel discrete wavelet decomposition layer SE-Residual block

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Enhanced thermoelectric and mechanical properties of Bi_(0.5)Sb_(1.5)Te_(3) alloy with dispersed yttrium oxide ceramic nanoparticles

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Rare Metals 2024年第4期43卷 1758-1768页

作者： Cun-Cheng Li Ming-wei Zhang Ji-Wu xin Lei wei Wen-Yu Zhao School of Materials Science and Engineering Shandong University of TechnologyZibo255000China School of Electrical and Electronic Engineering Nanyang Technological UniversitySingapore639798Singapore State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan430070China

Reducing thermal conductivity while avoiding adverse interfacial reactions during sintering is crucial for improving the thermoelectric performance of Bi_(2)Te_(3)based *** ceramic nanoparticles are good candidates for achieving this *** this study,we designed and prepared a series of p-type Bi_(0.5)Sb_(1.5)Te_(3)nanocomposites decorated with Y_(2)O_(3)ceramic nanoparticles via ball-milling dispersion and spark-plasma *** to the chemical stability of the ceramics,no traces of atomic doping or interfacial reactions were *** measurements revealed that the Y_(2)O_(3)nanoparticles distributed along the grain boundaries acted as energy-dependent carrier-filtering centers to improve the scattering parameter and Seebeck coefficient,contributing to the elevated power factor even with a decreased electrical ***,the incorporated Y_(2)O_(3)nanoparticles and various defect structures they induced effectively strengthened the phonon scattering and suppressed the lattice thermal ***,a peak figure of merit(ZT)of 1.23 at 313 K was achieved for 0.4%Y_(2)O_(3)/Bi_(0.5)Sb_(1.5)Te_(3),which is 13%higher than that of the *** addition,the Vickers hardness of the composite material was 35%higher than that of the *** study demonstrates the effectiveness of ceramic nanoparticles in synergistic ally improving the thermoelectric and mechanical properties,which may be further extended to other thermoelectric systems.

关键词： Bi_(0.5)Sb_(1.5)Te_3 alloy Y_(2)O_(3) ceramic nanoparticles Microstructures Thermoelectric performance Mechanical properties

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