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High Voltage 2018年第4期3卷 310-315页

作者： shampa de Abhinandan de Gautam Bandyopadhyay department of Electrical Engineering Netaji Subhash Engineering CollegeKolkataWest BengalIndia department of Electrical Engineering Indian Institute of Engineering Science and TechnologyHowrahWest BengalIndia

Interleaving of the high-voltage winding turns is a widely-accepted method for restraining the surge voltage stresses in extra high voltage(EHV)transformers.Reduction of voltage stresses under external surge is attributed by the increase in the self-capacitance of the interleaved winding disks.However,the apparent benefit of interleaving may be counterpoised by a significant decrease of natural frequency of windings,which in turn,may force a winding to resonate under external surges.Winding resonance is particularly noticeable when uniform interleaving is adopted for the whole winding,uniform interleaving attributes a unique natural frequency to all interleaved coils and consequently,the collective resonance of the winding disks is plausible.Uniform interleaving in large EHV transformers therefore leads to complications and the windings reportedly exhibit an unexpectedly poor surge voltage response because of such internal resonances.This study describes a novel concept termed as‘graded interleaving’for EHV transformer windings to overcome resonance and to achieve an improved response against surge voltage.The performance of the proposed winding was tested on a 132/33 kV two-winding transformer with a tap changer using EMTP(ATP)simulations with encouraging results.Manufacturing and real-time implementation feasibility of the winding were verified with transformer manufacturers.

关键词： winding resonance capacitance

Magnetic properties of gadolinium and/or dysprosium substituted Sm-Co nanocomposite ribbons

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Journal of Rare Earths 2024年第6期42卷 1093-1100,I0004页

作者： Akila Raja shampa Aich department of Metallurgical A Materials EngineeringIndian Institute of Technology(IIT) Kharagpur721302India

The present study reported the influence of heavy rare-earth elements(Gd and/or Dy)on Sm-Co-based melt-spun ribbons.Microstructure and magnetic properties of Sm-Co-based(Sm_(1-x)RE_(x)Co_(5))ternary and quaternary systems were investigated.The X-ray diffraction,Auger spectroscopy,scanning electron microscopy(SEM)and transmission electron microscopy(TEM)analyses reveal the presence of the 1:5H and 2:17R phases in the as-spun ribbons.A high-temperature magnetic measurement reports a Curie temperature(Tc)at~825 and~869 K in Sm0.6Gd0.4Co5(ribbon A)and Sm_(0.6)Gd_(0.3)Dy_(0.1)Co_(5)(ribbon B),respectively.A low-temperature magnetic measurement on Sm0.6Gd0.3Dy0.1Co5 ribbons exhibits a type-2 SR(spin reorientation)behaviour at~72 K,which arises due to the presence of the DyCo5 phase.Room temperature magnetic measurements reveal that overall magnetic measurement(OMP)is about 24 and 29.9 for ribbons A and B,respectively.Consequently,the comparative investigations profess that ribbon B shows better magnetic performance due to Dy addition with reduced grain size.This observation indicates that the Gd and Dy substituted Sm-Co magnet can be a potential magnet for high-temperature applications.

关键词： Permanent magnets Melt-spinning Heavy rare-earth Curie temperature Rare earths

Stereotactic body radiotherapy in pancreatic adenocarcinoma

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Hepatobiliary & Pancreatic Diseases International 2024年第1期23卷 14-19页

作者： Carolina de la Pinta Radiation Oncology department Ramón y Cajal University HospitalIRYCISAlcaláUniversity28034 MadridSpain

Background:Stereotactic body radiotherapy(SBRT)in pancreatic cancer allows high delivery of radiation doses on tumors without affecting surrounding tissue.This review aimed at the SBRT application in the treatment of pancreatic cancer.Data sources:We retrieved articles published in MEDLINE/PubMed from January 2017 to december 2022.Keywords used in the search included:“pancreatic adenocarcinoma”OR“pancreatic cancer”AND“stereotactic ablative radiotherapy(SABR)”OR“stereotactic body radiotherapy(SBRT)”OR“chemoradiotherapy(CRT)”.English language articles with information on technical characteristics,doses and fractionation,indications,recurrence patterns,local control and toxicities of SBRT in pancreatic tumors were included.All articles were assessed for validity and relevant content.Results:Optimal doses and fractionation have not yet been defined.However,SBRT could be the standard treatment in patients with pancreatic adenocarcinoma in addition to CRT.Furthermore,the combination of SBRT with chemotherapy may have additive or synergic effect on pancreatic adenocarcinoma.Conclusions:SBRT is an effective modality for patients with pancreatic cancer,supported by clinical practice guidelines as it has demonstrated good tolerance and good disease control.SBRT opens a possibility of improving outcomes for these patients,both in neoadjuvant treatment and with radical intent.

关键词： Chemoradiotherapy Pancreatic adenocarcinoma Radiotherapy Stereotactic body radiotherapy Stereotactic ablative radiotherapy

Exfoliation,functionalization and antibacterial activity of transition metal dichalcogenides

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Tungsten 2024年第1期6卷 1-16页

作者： Avijit Mondal Mrinmoy de department of Organic Chemistry Indian Institute of ScienceBengaluru 560012India

Due to the growing resistance of available drugs to bacterial infection and the slow development of antibiotics,there is a continuous need to design and develop new antibacterial agents.The interest to develop transition metal dichalcogenides(TMDs)based antibacterial agents has significantly increased in recent years.This research interest is driven by their interesting properties such as metallic and semiconducting nature of different phases,electronic confinement,large surface to volume ratio,the possibility of surface functionalization,and their potential application as a material in biomedical sciences.Different synthetic strategies have been developed to synthesize monolayered TMDs and their functionalization with different bioactive molecules.Researchers have given a lot of effort to establish the structure-activity correlation between different TMDs and their antibacterial activity.Here,we have reviewed various exfoliation strategies for TMDs,different methods for their functionalization,and the antibacterial activity of different TMDs.

关键词： Transition metal dichalcogenides(TMD) Functionalization Antibacterial activity Antibacterial mechanism

ZnO/CeO_(2)/carbon xerogel composites with direct Z-scheme heterojunctions:Enhancing photocatalytic remediation of 4-chlorophenol under visible light

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Journal of Rare Earths 2024年第2期42卷 314-322,I0003页

作者： Nicolas Perciani de Moraes Maite Birkett de Campos Sanmartin Robson da Silva Rocha Abner de Siervo Marcos Roberto de Vasconcelos Lanza D.Amaranatha Reddy Lianqing Yu Liana Alvares Rodrigues Escola de Engenharia de Lorena-EEL/USP Estrada Municipal do Campinho S/NCEP 12602-810LorenaSao PauloBrazil Institute of Physics"Gleb Wataghin" Applied Physics DepartmentState University of Campinas13083-859CampinasSPBrazi Instituto de Quimica de Sao Carlos Universidade de Sao PauloAv.Trab.Sao Carlense400-Parque Arnold SchimidtSao CarlosSP13566-590Spain department of Sciences Indian Institute of Information Technology Design and ManufacturingKurnoolAndhra Pradesh518007India School of Materials Science and Engineering China University of PetroleumQingdao266580China

This paper aims to create visible light driven ternary photocatalysts using zinc oxide(ZnO),cerium(IV)oxide(CeO_(2)),and carbon xerogel(CX) as constituent materials.The use of CeO_(2) is based on the creation of direct-Z-scheme heterojunctions with the ZnO and the consequent diminishing of charge recombination,whereas the carbon xerogel inclusion is predicted to minimize bandgap energy,decrease electro n-hole reco mbination,and boost specific surface area.Furthermo re,the choice of the black-wattle tannin as a carbonaceous precursor was targeted at the development of an environmentally friendly and affordable composite.The existence of the hexagonal phase of zinc oxide and cubic structure of the cerium(IV) oxide in the ternary material was confirmed by X-ray diffractometry and X-ray photoelectron spectroscopy,with the latter also suggesting chemical bonding between the ZnO and the CX due to the creation of zinc oxycarbide complexes.The inclusion of the carbon xerogel provokes a significant modification in the morphology of the ternary material,resulting in an increased surface area and smaller particle aggregates.The CX/ZnO-CeO_(2) ternary composite obtains the highest photocatalytic efficiency among all the materials studied,degrading 100% of 4-chlorophenol under simulated sunlight and 68% under visible radiation,after 5 h.The increased photocatalytic activity can be attributed to the formation of direct Z-scheme heterojunctions between the semiconductors,higher visible light response,and higher specific surface area,as evidenced by the results obtained by active radical scavenging,chronoamperometry,diffuse reflectance spectroscopy,and N_(2) adsorption-desorption isotherms.

关键词： Zinc oxide Cerium(Ⅳ)oxide Carbon xerogel Photocatalysis Direct Z-scheme heterojunction 4-Chlorophenol Rare earths

Supercritical fluid technology as a sustainable alternative method for textile dyeing:An approach on waste,energy,and CO_(2)emission reduction

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Journal of Environmental Sciences 2024年第6期140卷 123-145页

作者： Carlos Rafael Silva de Oliveira Patrícia Viera de Oliveira Leandro Pellenz Catia Rosana Lange de Aguiar Afonso Henrique da Silva Júnior Federal University of Santa Catarina Textile Engineering Department2514 João Pessoa St.BlumenauSC89036-004Brazil Federal University of Santa Catarina Chemical Engineering DepartmentS/n Biotério Central St.FlorianópolisSC88040-900Brazil

The clothing industry is considered one of the most polluting industries on the planet due to the high consumption of water,energy,chemicals/dyes,and high generation of solid waste and effluents.Faced with environmental concerns,the textile ennoblement sector is the most critical of the textile production chain,especially the traditional dyeing processes.As an alternative to current problems,dyeing with supercritical CO_(2)(scCO_(2))has been presented as a clean and efficient process for a sustainable textile future.Supercritical fluid dyeing(SFD)has shown a growing interest due to its significant impact on environmental preservation and social,economic,and financial gains.The main SFD benefits include economy and reuse of non-adsorbed dyes;reduction of process time and energy expenditure;capture of atmospheric CO_(2)(greenhouse gas);use and recycling of CO_(2)in SFD;generation of carbon credits;water-free process;effluent-free process;reduction of CO_(2)emission and auxiliary chemicals.despite being still a non-scalable and evolving technology,SFD is the future of dyeing.This review presented a comprehensive overview of the environmental impacts caused by traditional processes and confronted the advantages of SFD.The SFD technique was introduced,along with its latest advances and future perspectives.Financial and environmental gains were also discussed.

关键词： Textile industry Supercritical dyeing Sustainable processes Water free dyeing Energy saving Cleaner production

China stroke surveillance report 2021

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Military Medical Research 2024年第3期11卷 374-399页

作者： Wen-Jun Tu Long-de Wang 无 department of Neurosurgery Beijing Tiantan HospitalCapital Medical UniversityBeijing 100070China School of Public Health Peking UniversityBeijing 100191China Special Writing Group of China Stroke Surveillance Report

Since 2015,stroke has become the leading cause of death and disability in China,posing a significant threat to the health of its citizens as a major chronic non-communicable disease.According to the China Stroke High-risk Population Screening and Intervention Program,an estimated 17.8 million[95%confidence interval(CI)17.6–18.0million]adults in China had experienced a stroke in 2020,with 3.4 million(95%CI 3.3–3.5 million)experiencing their first-ever stroke and another 2.3 million(95%CI 2.2–2.4 million)dying as a result.Additionally,approximately 12.5%(95%CI 12.4%–12.5%)of stroke survivors were left disabled,as defined by a modified Rankin Scale score greater than 1,equating to 2.2 million(95%CI 2.1–2.2 million)stroke-related disabilities in 2020.As the population ages and the prevalence of risk factors like diabetes,hypertension,and hyperlipidemia continues to rise and remains poorly controlled,the burden of stroke in China is also increasing.A large national epidemiological survey initiated by the China Hypertension League in 2017 showed that the prevalence of hypertension was 24.7%;the awareness,treatment,and control rates in hypertensive patients were:60.1%,42.5%,and 25.4%,respectively.A nationally representative sample of the Chinese mainland population showed that the weighted prevalence of total diabetes diagnosed by the American Diabetes Association criteria was 12.8%,suggesting there are 120 million adults with diabetes in China,and the awareness,treatment,and control rates in diabetic patients were:43.3%,49.0%,and 49.4%,respectively.The“Sixth National Health Service Statistical Survey Report in 2018”showed that the proportion of the obese population in China was 37.4%,an increase of 7.2 points from 2013.Data from 1599 hospitals in the Hospital Quality Monitoring System and Bigdata Observatory Platform for Stroke of China(BOSC)showed that a total of 3,418,432 stroke cases[mean age±standard error(SE)was(65.700±0.006)years,and 59.1%were male]were admitted during 2020.Of those,over 80.0%(81.9%)were ischemic

关键词： Stroke Epidemiological characteristics Treatment Prognosis China

Stability of the Stratification of Water Bodies in the North Passage of the Yangtze River Estuary Based on the EFDC Model

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Journal of Ocean University of China 2024年第1期23卷 23-32页

作者： WU de’an LI Xin WANG Yigang College of Harbor Coastal and Offshore EngineeringHohai UniversityNanjing 210098China Tianjin Research Institute For Water Transport Engineering Tianjin 300456China

To study the stratified stability of a water column in the North Passage of the Yangtze River Estuary,a numerical model of the hydrodynamics of this estuary is established using the EFDC model.On the basis of EFDC results,this paper derives and pro-vides the discriminative index of water body stability caused by salinity and analyzes the along-range variation in water body strati-fication stability in the North Passage of the Yangtze River Estuary and the periodic variation at a key location(bend area)based on the simulation results of the numerical model.This work shows that the water body in the bend area varies between mixed and strati-fied types,and the vertical average flow velocity has a good negative correlation with the differential velocity between the surface and bottom layers of the water body.The model simulation results validate the formulae for the stratified stability discriminant during spring tides.

关键词： Yangtze Estuary North Passage EFDC model stratification stability salinity distribution

Optimal Risk Sharing for Maxmin Choquet Expected Utility Model

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 430-444页

作者： de-jian TIAN Shang-ri WU School of Mathematics China University of Mining and TechnologyXuzhou 221116China

This article analyzes the Pareto optimal allocations,agreeable trades and agreeable bets under the maxmin Choquet expected utility(MCEU)model.We provide several useful characterizations for Pareto optimal allocations for risk averse agents.We derive the formulation descriptions for non-existence agreeable trades or agreeable bets for risk neutral agents.We build some relationships between ex-ante stage and interim stage on agreeable trades or bets when new information arrives.

关键词： maxmin Choquet expected utility model Pareto optimal allocation agreeable trade agreeable bet

Optimizing prediction models for pancreatic fistula after pancreatectomy:Current status and future perspectives

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World Journal of Gastroenterology 2024年第10期30卷 1329-1345页

作者： Feng Yang John A Windsor de-Liang Fu department of Pancreatic Surgery Huashan HospitalShanghai Medical CollegeFudan UniversityShanghai 200040China Surgical and Translational Research Centre Faculty of Medical and Health SciencesUniversity of AucklandAuckland 1142New Zealand

Postoperative pancreatic fistula(POPF)is a frequent complication after pancre-atectomy,leading to increased morbidity and mortality.Optimizing prediction models for POPF has emerged as a critical focus in surgical research.Although over sixty models following pancreaticoduodenectomy,predominantly reliant on a variety of clinical,surgical,and radiological parameters,have been documented,their predictive accuracy remains suboptimal in external validation and across diverse populations.As models after distal pancreatectomy continue to be pro-gressively reported,their external validation is eagerly anticipated.Conversely,POPF prediction after central pancreatectomy is in its nascent stage,warranting urgent need for further development and validation.The potential of machine learning and big data analytics offers promising prospects for enhancing the accuracy of prediction models by incorporating an extensive array of variables and optimizing algorithm performance.Moreover,there is potential for the development of personalized prediction models based on patient-or pancreas-specific factors and postoperative serum or drain fluid biomarkers to improve accuracy in identifying individuals at risk of POPF.In the future,prospective multicenter studies and the integration of novel imaging technologies,such as artificial intelligence-based radiomics,may further refine predictive models.Addressing these issues is anticipated to revolutionize risk stratification,clinical decision-making,and postoperative management in patients undergoing pancre-atectomy.

关键词： Pancreatic fistula Pancreaticoduodenectomy Distal pancreatectomy Central pancreatectomy Prediction model Machine learning Artificial intelligence