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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

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服装直播带货模式分析及绿色直播策略

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天津纺织科技 2024年第3期 28-33页

作者：邵鹏易薇西安工程大学管理学院陕西西安710048

基于商业模式理论对服装直播带货模式进行案例研究,从消费者、商家、监管机构3个方面提出促进服装绿色直播建议。研究发现,服装商家通过价值主张、价值创造、价值获取为消费者提供直播带货服务,并已经开始践行绿色直播;直播带货的绿色... 详细信息

基于商业模式理论对服装直播带货模式进行案例研究,从消费者、商家、监管机构3个方面提出促进服装绿色直播建议。研究发现,服装商家通过价值主张、价值创造、价值获取为消费者提供直播带货服务,并已经开始践行绿色直播;直播带货的绿色消费提升空间主要集中在直播销售过程、直播商品属性两方面。建议消费者应从决策过程和商品属性两方面践行绿色消费,商家应参照责任延伸制度促进绿色直播,监管机构应制定完善的服装绿色直播规范。

关键词：服装直播带货绿色直播电子商务数字化消费

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Synergistically enhanced dielectric, insulating and thermally conductive performances of sandwich PMMA based dielectric films

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Progress in Natural Science:Materials International 2024年第3期34卷 591-597页

作者： Dongmei Zhang Yufan Li Yuchao Li Zhonggui Sun Hanxue Zhu Lujia Yang Yanhu Zhan Yankai Li Shi Wang Jun-wei Zha School of Mathematical Sciences Liaocheng University School of Materials Science and Engineering Liaocheng University State Key Laboratory of Organic Electronics and Information Displays & Institute of Advanced Materials (IAM) Nanjing University of Posts & Telecommunications School of Chemistry and Biological Engineering University of Science and Technology Beijing

A tri-layered(B-G-B) dielectric films were simply prepared by alternatively spin-coating boron nitride/polymethylmethacrylate(BN/PMMA, B) and graphene nanosheets(GNS/PMMA, G) compound solutions. The structure, morphology, thermal conductivity, and particularly the dielectric and relaxation behaviors were systematically studied. Results showed that a good exfoliation and dispersion of BN and GNS can be simply achieved through intensive mechanical compounding with PMMA in the internal mixer. The dielectric constant and breakdown strength of the obtained 1-3-1(B-G-B) sandwich composite film reached 4.3(@1 kHz) and 458.6kV/mm, being 119 % and 113 % higher than that of pure PMMA, respectively. Furthermore, the overall thermal conductivity of sandwich 1-3-1 composite increased by 112 % due to the addition of thermally conductive BN and GNS. The sandwich design strategy provided an effective way of achieving good permittivity, high insulation, and improved thermal conductivity simultaneously, showing potential applications in the miniaturization and integration of electronic devices.

关键词： Sandwich structure Breakdown strength Thermal conductivity Dielectric constant Composites

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Silurian integrative stratigraphy,biotas,and paleogeographical evolution of the Qinghai-Tibetan Plateau and its surrounding areas

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Science China Earth Sciences 2024年第4期67卷 1005-1035页

作者： Zhongyang CHEN Qing CHEN Guangxu WANG Xiang FANG Peng TANG Guanzhou YAN Wenwei YUAN Bing HUANG Xiaole ZHANG Kui YAN Yuandong ZHANG yi WANG State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of SciencesNanjing 210008China University of Chinese Academy of Sciences Beijing 100049China

The Silurian palaeontology and stratigraphy of the Qinghai-Tibetan Plateau have been studied for more than100 *** the launch of the Second Tibetan Plateau Scientific Expedition and Research,it is necessary to update the summaries of the Silurian stratigraphy and fossil assemblages of the Qinghai-Tibetan Plateau and their correlation with its surrounding *** this study,we have selected 33 sections from the Qinghai-Tibetan Plateau and its surroundings areas,summarised the available data in terms of stratigraphic regionalisation,lithostratigraphy,chronostratigraphy,and biostratigraphy,and divided the study area into four stratigraphic provinces:the Xizang-Western Yunnan-Western Sichuan Province,the KunlunQilian Province,the South China Province,and the Tarim *** general,the Silurian strata in the Qinghai-Tibetan Plateau is more complete than those in other areas of *** studies of the vertebrate faunas,sporomorph assemblages,and brachiopod faunas of the study area indicate a closer geographical relationship between the South China,Tarim,and Indochina palaeoplates,than previously *** with the surrounding areas where Silurian strata have been extensively studied,the study of Silurian strata in the main part of the Qinghai-Tibetan Plateau is still in the preliminary *** the future,it is necessary to conduct research on the age,distribution,and resource potential of basal Silurian black shales to provide new directions for shale gas exploration and development in *** shallow marine strata of the middle to upper Silurian require further *** that the Silurian System in the Qinghai-Tibetan Plateau is more complete,it has the potential to supplement and improve the study of the carbon isotope stratigraphy of the Silurian in China.

关键词： Qinghai-Tibetan Plateau Silurian Stratigraphic regionalisation Lithostratigraphy Biostratigraphy Palaeogeographical evolution

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Risk Factors of Enternal Nutrition Intolerance in Septic Patients:A Case-control Study

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Current Medical Science 2024年第2期44卷 328-332页

作者： Li-zhu WANG Yan XIANG Qian LI yi-rong ZHU Jue FANG Xiao-dan LU Zhao-cai ZHANG Department of Nursing The Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310009China Department of Critical Care Medicine The Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310009China Key Laboratory of the Diagnosis and Treatment for Severe Trauma and Burn of Zhejiang Province Hangzhou 310009China Zhejiang Province Clinical Research Center for Emergency and Critical Care Medicine Hangzhou 310009China

Objective:This study aimed to investigate the incidence of enteral nutrition intolerance(ENI)in patients with sepsis and explore potential risk ***:A case-control study was conducted in patients with sepsis who were receiving enteral nutrition(EN)at a tertiary hospital in *** included patients were divided into the ENI group and the non-ENI *** and multivariate analyses were performed to identify the risk factors for ***:A total of 859 patients were included in the *** them,288(33.53%)patients experienced symptoms of ENI,including diarrhea,vomiting,bloating,and gastric *** regression analysis revealed that the Acute Physiology and Chronic Health Evaluation H(APACHE H)score,thoracocentesis,and usage of cardiotonic drugs(namely,inotropes)were independent predictors of the ***:The incidence of ENI is relatively high in patients with sepsis,especially in those who have higher APACHE H scores,have undergone thoracocentesis,and have received inotropes.

关键词： sepsis enteral nutrition intolerance influencing factor

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Comparison of prognosis and postoperative morbidities between standard pancreaticoduodenectomy and the TRIANGLE technique for resectable pancreatic ductal adenocarcinoma

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World Journal of Gastrointestinal Surgery 2024年第3期16卷 689-699页

作者： He-Xing Hang Zheng-Hua Cai yi-Fei Yang Xu Fu Yu-Dong Qiu Hao Cheng Division of Pancreatic Surgery Department of General SurgeryNanjing Drum Tower HospitalThe Affiliated Hospital of Medical SchoolNanjing UniversityNanjing 210008Jiangsu ProvinceChina

BACKGROUND Radical surgery combined with systemic chemotherapy offers the possibility of long-term survival or even cure for patients with pancreatic ductal adenocar-cinoma(PDAC),although tumor recurrence,especially locally,still inhibits the treatment *** TRIANGLE technique was introduced as an extended dissection procedure to improve the R0 resection rate of borderline resectable or locally advanced ***,there was a lack of studies concerning postoperative complications and long-term outcomes of this procedure on patients with resectable *** Patients with resectable PDAC eligible for PD from our hospital between June 2018 and December 2021 were enrolled in this retrospective cohort *** the patients were divided into PDstandard and PDTRIANGLE groups according to the surgical *** characteristics,surgical data,and postoperative morbidities were *** of the patients were followed up,and the date and location of tumor recurrence,and death were *** Kaplan-Meier method and log-rank test were used for the survival *** There were 93 patients included in the study and 37 underwent the TRIANGLE *** of operation was longer in the PDTRIANGLE group compared with the PDstandard group[440(410-480)min vs 320(265-427)min](P=0.001).Intraoperative blood loss[700(500-1200)mL vs 500(300-800)mL](P=0.009)and blood transfusion[975(0-1250)mL vs 400(0-800)mL](P=0.009)were higher in the PDTRIANGLE *** was a higher incidence of surgical site infection(43.2%vs 12.5%)(P=0.001)and postoperative diarrhea(54.1%vs 12.5%)(P=0.001)in the PDTRIANGLE *** rates of R0 resection and local recurrence,overall survival,and disease-free survival did not differ significantly between the two *** The TRIANGLE technique is safe,with acceptable postoperative morbidities compared with standardized PD,but it does not improve prognosis for patients with resectable PDAC.

关键词： Pancreatic ductal adenocarcinoma TRIANGLE technique Pancreaticoduodenectomy Prognosis Postoperative morbidities

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Self-supported copper-based gas diffusion electrodes improve the local CO_(2)concentration for efficient electrochemical CO_(2)reduction

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Frontiers of Chemical Science and Engineering 2024年第3期18卷 51-62页

作者： Azeem Mustafa Bachirou Guene Lougou Yong Shuai Zhijiang Wang Haseeb-ur-Rehman Samia Razzaq wei Wang Ruming Pan Jiupeng Zhao Key Laboratory of Aerospace Thermophysics of MIIT Harbin Institute of TechnologyHarbin150001China School of Energy Science and Engineering Harbin Institute of TechnologyHarbin150001China MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage School of Chemistry and Chemical EngineeringHarbin Institute of TechnologyHarbin150001China Mechanical Engineering Department University of Engineering and TechnologyTaxila47050Pakistan School of Aerospace Mechanical and Mechatronics EngineeringUniversity of SydneySydney2006Australia

Electrochemical CO_(2)reduction is a sustainable approach in green chemistry that enables the production of valuable chemicals and fuels while mitigating the environmental impact associated with CO_(2)*** its several advantages,this technology suffers from an intrinsically low CO_(2)solubility in aqueous solutions,resulting in a lower local CO_(2)concentration near the electrode,which yields lower current densities and restricts product *** diffusion electrodes(GDEs),particularly those with tubular architectures,can solve these issues by increasing the local CO_(2)concentration and triple-phase interface,providing abundant electroactive sites to achieve superior reaction *** this study,robust and self-supported Cu flow-through gas diffusion electrodes(FTGDEs)were synthesized for efficient formate production via electrochemical CO_(2)*** were further compared with traditional Cu electrodes,and it was found that higher local CO_(2)concentration due to improved mass transfer,the abundant surface area available for the generation of the triple-phase interface,and the porous structure of Cu FTGDEs enabled high formate Faradaic efficiency(76%)and current density(265 mA¸cm^(−2))at–0.9 V *** hydrogen electrode(RHE)in 0.5 mol·L^(−1)*** combined phase inversion and calcination process of the Cu FTGDEs helped maintain a stable operation for several *** catalytic performance of the Cu FTGDEs was further investigated in a non-gas diffusion configuration to demonstrate the impact of local gas concentration on the activity and performance of electrochemical CO_(2)*** study demonstrates the potential of flow-through gas-diffusion electrodes to enhance reaction kinetics for the highly efficient and selective reduction of CO_(2),offering promising applications in sustainable electrochemical processes.

关键词： CO_(2)electroreduction flow-through delivery hollow fiber structure local concentration formate

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Boosting cycling stability by regulating surface oxygen vacancies of LNMO by rapid calcination

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Nano Research 2024年第4期17卷 2671-2677页

作者： Haoran Jiang Cuihua Zeng wei Zhu Jiawei Luo Zhedong Liu Jingchao Zhang Rui Liu Yunhua Xu Yanan Chen Wenbin Hu School of Materials Science and Engineering Tianjin UniversityTianjin 300072China School of Materials Science and Engineering Shandong University of Science and TechnologyQingdao 266590China

Spinel LiNi_(0.5-x)Mn_(1.5+x)O_(4)(LNMO)has attracted intensive interest for lithium-ion battery due to its high voltage and high energy ***,severe capacity fade attributed to unstable surface structure has hampered its *** vacancies(OVs)tend to occur in the surface of the material and lead to surface structure reconstruction,which deteriorates the battery performance during electrochemical ***,we utilize high-temperature-shock(HTS)method to synthesize LNMO materials with fewer surface *** calcination drives lower surface OVs concentration,reducing the content of Mn^(3+)and surface reconstruction layers,which is beneficial to obtain a stable crystal *** LNMO material synthesized by HTS method delivers an initial capacity of 127 mAh·g^(-1) at 0.1 C and capacity retention of 81.6%after 300 cycles at 1 C,and exhibits excellent performance at low temperature.

关键词： ultrafast synthesis oxygen vacancy LiNi_(0.5-x)Mn_(1.5+x)O_(4)(LNMO)cathode high-temperature-shock lithium-ion batteries

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Direct observation of oxygen vacancy formation and migration over ceria surface by in situ environmental transmission electron microscopy

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Journal of Rare Earths 2024年第4期42卷 676-682页

作者： Dawei Pang wei Li Ningqiang Zhang Hong He Shengcheng Mao Yanhui Chen Liwei Cao Chong Li Ang Li Xiaodong Han Beijing Key Laboratory of Solid Microstructure and Properties Department of Materials and ManufacturingBeijing University of TechnologyBeijing 100124China Beijing Key Laboratory for Green Catalysis and Separation The Faculty of Environment and LifeBeijing University of TechnologyBeijing10124China International Joint Research Laboratory for Quantum Functional Materials of Henan School of Physics and MicroelectronicsZhengzhou UniversityZhengzhou450001China

The extremely high structural tolerance of ceria to oxygen vacancies(Ov)has made it a desirable catalytic material for the hydrocarbon oxidation to chemicals and pharmaceuticals and the reduction of gaseous *** is proposed that the formation and diffusion of Ov originate from its outstanding reduction ***,the formation and diffusion process of Ov over the surface of ceria at the atomic level is still ***,the structural and valence evolution of CeO_(2)(111)surfaces in reductive,oxidative and vacuum environments from room temperature up to 700℃was studied with in situ aberration-corrected environmental transmission electron microscopy(ETEM)*** is found to form under a high vacuum at elevated temperatures;however,the surface can recover to the initial state through the adsorption of oxygen atoms in an oxygen-contained ***,in hydrogen environment,the step-CeO_(2)(111)surface is not stable at elevated temperatures;thus,the steps tend to be eliminated with increasing *** with first-principles density function calculations(DFT),it is proposed that O-terminated surfaces would develop in a hypoxic environment due to the dynamic diffusion of Ov from the outer surface to the ***,in a reductive environment,H2 facilitates the formation and diffusion of Ov while Ce-terminated surfaces *** results reveal dynamic atomic-scale interplay between the nanoceria surface and gas,thereby providing fundamental insights into the Ov-dependent reaction of nano-CeO_(2) during catalytic processes.

关键词： Ceria Direct observation In situ ETEM Oxygen vacancy Density function calculations Rareearths

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Multi-objective global optimization approach predicted quasi-layered ternary TiOS crystals with promising photocatalytic properties

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Chinese Physics B 2024年第8期33卷 447-454页

作者：向依婕高思妍王春雷方海平段香梅郑益峰张越宇 Shanghai Institute of Applied Physics Chinese Academy of Sciences University of Chinese Academy of Sciences School of Materials Science and Engineering East China University of Science and Technology College of Science Shanghai University School of Physics East China University of Science and Technology School of Physical Science and Technology Ningbo University Wenzhou Institute University of Chinese Academy of Sciences (UCAS)

Titanium dioxide（TiO2） has attracted considerable research attentions for its promising applications in solar cells and photocatalytic ***,the intrinsic challenge lies in the relatively low energy conversion efficiency of TiO2,primarily attributed to the substantial band gaps（exceeding 3.0 eV） associated with its rutile and anatase *** multi-objective global optimization,we have identified two quasi-layered ternary Ti-O-S crystals,composed of titanium,oxygen,and *** calculations of formation energy,phonon dispersions,and thermal stability confirm the chemical,dynamical and thermal stability of these newly discovered *** the state-of-art hybrid density functional approach and many-body perturbation theory（quasiparticle GW approach and Bethe-Salpeter equation）,we calculate the optical properties of both the TiOS ***,both phases show favorable photocatalytic characteristics,featuring band gaps suitable for visible optical absorption and appropriate band alignments with water for effective charge carrier ***,ternary compound TiOS holds the potential for achieving high-efficiency photochemical conversion,showing our multi-objective global optimization provides a new approach for novel environmental and energy materials design with multicomponent compounds.

关键词： first principles calculations multi-objective global optimization photocatalysis

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