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Working condition recognition of sucker rod pumping system based on 4-segment time-frequency signature matrix and deep learning

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Petroleum Science 2024年第1期21卷 641-653页

作者： yun-peng He Hai-Bo cheng peng Zeng Chuan-Zhi Zang Qing-Wei Dong Guang-Xi Wan Xiao-Ting Dong State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang 110016LiaoningChina Key Laboratory of Networked Control Systems Chinese Academy of SciencesShenyang 110016LiaoningChina Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang 110169LiaoningChina University of Chinese Academy of Sciences Beijing100049China School of Artifcial Intelligence Shenyang University of TechnologyShenyang 110870LiaoningChina

High-precision and real-time diagnosis of sucker rod pumping system(SRPS)is important for quickly mastering oil well *** learning-based method for classifying the dynamometer card(DC)of oil wells is an efficient diagnosis ***,the input of the DC as a two-dimensional image into the deep learning framework suffers from low feature utilization and high computational ***,different SRPSs in an oil field have various system parameters,and the same SRPS generates different DCs at different ***,there is heterogeneity in field data,which can dramatically impair the diagnostic *** solve the above problems,a working condition recognition method based on 4-segment time-frequency signature matrix(4S-TFSM)and deep learning is presented in this ***,the 4-segment time-frequency signature(4S-TFS)method that can reduce the computing power requirements is proposed for feature extraction of DC ***,the 4S-TFSM is constructed by relative normalization and matrix calculation to synthesize the features of multiple data and solve the problem of data ***,a convolutional neural network(CNN),one of the deep learning frameworks,is used to determine the functioning conditions based on the *** on field data verify that the proposed diagnostic method based on 4S-TFSM and CNN(4S-TFSM-CNN)can significantly improve the accuracy of working condition recognition with lower computational *** the best of our knowledge,this is the first work to discuss the effect of data heterogeneity on the working condition recognition performance of SRPS.

关键词： Sucker-rod pumping system Dynamometer card Working condition recognition Deep learning Time-frequency signature Time-frequency signature matrix

Transcriptomic and cellular decoding of scaffolds-induced suture mesenchyme regeneration

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International Journal of Oral Science 2024年第2期16卷 306-321页

作者： Jiayi Wu Feifei Li peng yu Changhao yu Chuyi Han Yitian Wang Fanyuan yu Ling Ye State Key Laboratory of Oral Diseases&National Center for Stomatology&National Clinical Research Center for Oral Diseases&West China Hospital of Stomatology Sichuan UniversityChengduChina State Key Laboratory of Oral Diseases&National Center for Stomatology&National Clinical Research Center for Oral Diseases&Department of Cariology and Endodontics West China Hospital of StomatologySichuan UniversityChengduChina State Key Laboratory of Oral Diseases&National Center for Stomatology&National Clinical Research Center for Oral Diseases&Department of Pediatric Dentistry West China Hospital of StomatologySichuan UniversityChengduChina

Precise orchestration of cell fate determination underlies the success of scaffold-based skeletal *** extensive studies on mineralized parenchymal tissue rebuilding,regenerating and maintaining undifferentiated mesenchyme within calvarial bone remain very challenging with limited advances *** knowledge has evidenced the indispensability of rebuilding suture mesenchymal stem cell niches to avoid severe brain or even systematic *** to date,the absence of promising therapeutic biomaterials/scaffolds *** reason lies in the shortage of fundamental knowledge and methodological evidence to understand the cellular fate regulations of *** address these issues,in this study,we systematically investigated the cellular fate determinations and transcriptomic mechanisms by distinct types of commonly used calvarial *** data elucidated the natural processes without scaffold transplantation and demonstrated how different scaffolds altered in vivo cellular responses.A feasible scaffold,polylactic acid electrospinning membrane(PLA),was next identified to precisely control mesenchymal ingrowth and self-renewal to rebuild non-osteogenic suture-like tissue at the defect center,meanwhile supporting proper osteointegration with defect bony ***,transcriptome analysis and cellular mechanisms underlying the well-orchestrated cell fate determination of PLA were *** study for the first time cellularly decoded the fate regulations of scaffolds in suture-bony composite defect healing,offering clinicians potential choices for regenerating such complicated injuries.

关键词： injuries healing suture

Interfacial friction effects on sealing performances of elastomer packer

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Petroleum Science 2024年第3期21卷 2037-2047页

作者： peng-cheng Wang Ming-Hui Chen Jim Jenkinson Yong-Xin Song Li Sun Department of Mechanical Engineering University of HoustonHoustonTX77024USA Guren Nanomaterials Suzhou215127JiangsuChina Department of Marine Engineering Dalian Maritime UniversityDalian116026LiaoningChina

Elastomer sealing performance is of critical importance for downhole tools application including the use of fracturing(Frac)plugs during multi-stage hydraulic *** practice sealing performances of such plugs are normally evaluated through pressure tests,and in numerical simulation studies,maximum contact stress,average contact stress and contact length data are used to determine sealing quality between a packer and *** previous studies,the impact of friction forces on sealing performance is often *** work aims to fill this knowledge gap in determining the influence of friction forces on elastomer packer sealing *** first determined the most appropriate constitutive hyperelastic model for the elastomers used in frac *** we compared analytical calculation results with Finite Element Analysis simulation using a simplified tubular geometry and showed the significant influences on interfacial friction on elastomer packer stress distribution,deformation,and contact stress after *** the demonstration of validity of FEA method,we conducted systematic numerical simulation studies to show how the interfacial friction coefficients can affect the maximum contact stress,average contact stress,contact stress distribution,and maximum mises stress for an actual packer used in plug *** addition,we also demonstrated how the groove in a packer can affect packer deformation and evolvement during setting with the consideration of interfacial *** study underscores the critical role that friction forces play in Frac plug performance and provides a new dimension for optimizing packer design by controlling interfacial interactions at the packer contact surfaces.

关键词： Elastomer seal Friction Sealing performance Contact stress

Gastric cancer immunotherapy:A scientometric and clinical trial review

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World Journal of Gastroenterology 2024年第2期30卷 196-198页

作者： Qian-cheng Du Xin-yu Wang Hua yu Thoracic Surgery Shanghai Xuhui Central HospitalShanghai 200031China Thyroid Breast and Vascular SurgeryShanghai Fourth People’s Hospital Affiliated to Tongji University School of MedicineShanghai 200434China Department of General Surgery Shanghai Fourth People’s Hospital Affiliated to Tongji University School of MedicineShanghai 200434China

This letter is intended to arouse your interest in a recent review of comprehensive scientometrics and clinical trials on immunotherapy for gastric cancer(GC).Our study reviews recent advances in immunotherapy in the field of GC and highlights its new prospects as a treatment for *** research reveals China’s leadership in this field,as well as new therapeutic strategies such as immune checkpoint inhibitors,cellular immunotherapy,and *** combined findings highlight the potential of immunotherapy to improve survival and quality of life in patients with stomach *** believe that this study will provide important guidance for the future direction of the GC treatment field.

关键词： Gastric cancer Immunotherapy Bibliometrics Comment Therapeutic strategies

Recent advances in post-chiroptical manipulation of supramolecular aggregates assembled with molecular modules

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Science China Chemistry 2024年第9期67卷 2842-2863页

作者： Yanling Shen Wanhua Wu Zhipeng yu cheng Yang Key Laboratory of Green Chemistry & Technology of Ministry of Education College of Chemistry Institution Sichuan University

Recently, various supramolecular assembly systems have been identified where the pre-existing chiral supramolecular structure can be manipulated through environmental adjustments, such as temperature, solvent, and concentration. These changes result in diverse microscopic morphologies during the assembly process and induce chiroptical variations, particularly in circular dichroism(CD) and circularly polarized luminescence(CPL) spectra. These chiroptical properties serve as direct indicators of the chiral supramolecular structure and hold promise for applications in sensing, molecular recognition, asymmetric synthesis, and material science. This review focuses on research published in the last five years, highlighting instances where assembled structures aggregated by small organic molecular modules demonstrate in-situ chiroptical changes through external condition control. It categorizes and discusses different modes of regulation, aiming to offer insights and guidelines for exploring dynamic changes in assembly processes and designing in-situ adjustable structures of assembly modules.

关键词： supramolecular assemblies post-chiroptical manipulation in-situ structural changes

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Pd-catalyzed intermolecular Si–O formation via Si–C activation

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Science China Chemistry 2024年第8期67卷 2661-2669页

作者： Shuang Liu yu-Shu Chen Yichen Wu peng Wang State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesShanghai 200032China School of Chemistry and Materials Science Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China College of Material Chemistry and Chemical Engineering Key Laboratory of Organosilicon Chemistryand Material Technology of Ministry of EducationHangzhou Normal UniversityHangzhou 311121China

The development of efficient Si–O bond formation reaction with 100% atom-economy, excellent functional group tolerance, and broad scope under mild conditions is highly desired due to the prevalence of silanol, silyl ether, and their derivatives in synthetic chemistry and materials science. Here, we have realized the Pd-catalyzed Si–O formation reaction via a Si–C activation approach with 100% atom-economy by employing silacyclobutanes(SCBs) and various hydroxy-containing substrates, including water,alcohols, phenols, and silanols. This protocol features a broad substrate scope, remarkable functional compatibility and mild conditions, providing a series of silanols, silyl ethers in high efficiency. Notably, this protocol could also be used for selective protection of hydroxy functionalities, and for the access of a class of novel polymers containing Si–O main chain. Preliminary mechanistic studies unveiled that this reaction underwent a Pd-catalyzed concerted ring-opening mechanism.

关键词： Si–O formation Si–C activation palladium silacyclobutane silanol silyl ether

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Synthesis of NaY zeolite from a submolten depolymerized perlite:Alkalinity effect and crystallization kinetics

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Chinese Journal of Chemical Engineering 2024年第6期70卷 130-138页

作者： Yanli Qu peng Dong Li Yang yuanyuan yue Haoliang Wang Jingcai cheng Chao Yang CAS Key Laboratory of Green Process and Engineering State Key Laboratory of Petroleum Molecular&Process EngineeringInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100190China Qingyuan Innovation Laboratory Quanzhou 362801China National Engineering Research Center of Chemical Fertilizer Catalyst College of Chemical EngineeringFuzhou UniversityFuzhou 350108China

NaY zeolites are synthesized using submolten salt depolymerized natural perlite mineral as the main silica and alumina sources in a 0.94 L stirred *** of alkalinity ranging from 0.38 to 0.55(n(Na_(2)O)/n(SiO_(2)))on the relative crystallinity,textural properties and crystallization kinetics were *** results show that alkalinity exerts a nonmonotonic influence on the relative crystallinity and textural properties,which exhibit a maximum at the alkalinity of *** nucleation kinetics are studied by fitting the experimental data of relative crystallinity with the Gualtieri *** is shown that the nucleation rate constant increases with increasing alkalinity,while the duration period of nucleation decreases with increasing *** n(Na_(2)O)/n(SiO_(2))ratios ranging from 0.38 to 0.55,the as-synthesized NaY zeolites exhibit narrower crystal size distributions with the increase in *** growth rates determined from the variations of average crystal size with time are 51.09,157.50,46.17 and 24.75 nm·h^(-1),*** is found that the larger average crystal sizes at the alkalinity of 0.38 and 0.43 are attributed to the dominant role of crystal growth over ***,the combined action of prominent crystal growth and the longer duration periods of nucleation at the alkalinity of 0.38 and 0.43 results in broader crystal size *** findings demonstrate that control of the properties of NaY zeolite and the crystallization kinetics can be achieved by conducting the crystallization process in an appropriate range of alkalinity of the reaction mixture.

关键词： NaY zeolite Submolten salt depolymerized perlite Alkalinity Crystallization kinetics

Suppression of current-induced membrane discharge of bipolar membranes by regulating ion crossover transport

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Journal of Energy Chemistry 2024年第9期96卷 387-395页

作者： Tingting yu Haolan Tao Jingkun Li cheng Lian Honglai Liu State Key Laboratory of Chemical Engineering Shanghai Engineering Research Center of Hierarchical NanomaterialsSchool of Chemical EngineeringEast China University of Science and TechnologyShanghai 200237China School of Chemistry and Molecular Engineering East China University of Science and TechnologyShanghai 200237China

Bipolar membranes(BPMs)exhibit the unique capability to regulate the operating environment of electrochemical system through the water dissociation-combination ***,the industrial utilization of BPMs is limited by instability and serious energy *** current-induced membrane discharge(CIMD)at high-current conditions has a negative influence on the performance of anion-exchange membranes,but the underlying ion transport mechanisms in the BPMs remain ***,the CIMD-coupled Poisson-Nernst-Planck(PNP)equations are used to explore the ion transport mechanisms in the BPMs for both reverse bias and forward bias at neutral and acid-base *** is demonstrated that the CIMD effect in the reverse-bias mode can be suppressed by enhancing the diffusive transport of salt counter-ions(Na^(+)and Cl^(−))into the BPMs,and that in the forward-bias mode with acid-base electrolytes can be suppressed by matching the transport rate of water counter-ions(H_(3)O^(+)and OH^(−)).Suppressing the CIMD can promote the water dissociation in the reverse-bias mode,as well as overcome the plateau of limiting current density and reduce the interfacial blockage of salt co-ions(Cl^(−))in the anion-exchange layer in the forward-bias mode with acid-base *** work highlights the importance of regulating ion crossover transport on improving the performance of BPMs.

关键词： Bipolar membranes Current-induced membrane discharge Salt ion crossover Diffusion-migration-reaction process

CCM-FL:Covert communication mechanisms for federated learning in crowd sensing IoT

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Digital Communications and Networks 2024年第3期10卷 597-608页

作者： Hongruo Zhang Yifei Zou Haofei Yin Dongxiao yu Xiuzhen cheng Institute of Intelligent Computing School of Computer Science and TechnologyShandong UniversityQingdao266237China

The past decades have witnessed a wide application of federated learning in crowd sensing,to handle the numerous data collected by the sensors and provide the users with precise and customized ***,how to protect the private information of users in federated learning has become an important research *** with the differential privacy(DP)technique and secure multiparty computation(SMC)strategy,the covert communication mechanism in federated learning is more efficient and energy-saving in training the ma-chine learning *** this paper,we study the covert communication problem for federated learning in crowd sensing Internet-of-Things *** from the previous works about covert communication in federated learning,most of which are considered in a centralized framework and experimental-based,we firstly proposes a centralized covert communication mechanism for federated learning among n learning agents,the time complexity of which is O(log n),approximating to the optimal ***,for the federated learning without parameter server,which is a harder case,we show that solving such a problem is NP-hard and prove the existence of a distributed covert communication mechanism with O(log logΔlog n)times,approximating to the optimal solution.Δis the maximum distance between any pair of learning *** analysis and nu-merical simulations are presented to show the performance of our covert communication *** hope that our covert communication work can shed some light on how to protect the privacy of federated learning in crowd sensing from the view of communications.

关键词： Covert communications Federated learning Crowd sensing SINR model