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Corrigendum regarding missing informed consents in previously published articles
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《Grain & Oil Science and Technology》 CAS 2024年第1期68-68,共1页
The publisher would like to draw the reader's attention to the following errors.Informed consents were not included in the published version of the following articles that appeared in previous issues of Grain&... The publisher would like to draw the reader's attention to the following errors.Informed consents were not included in the published version of the following articles that appeared in previous issues of Grain&Oil Science and Technology.The authors were contacted after publication to request informed consents for the following articles.The appropriate informed consents,provided by the authors,are included below. 展开更多
关键词 consent INFORMED articles
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An explorative study on document type assignment of review articles in Web of Science,Scopus and journals’websites
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作者 Manman Zhu Xinyue Lu +2 位作者 Fuyou Chen Liying Yang Zhesi Shen 《Journal of Data and Information Science》 CSCD 2024年第1期11-36,共26页
Purpose:Accurately assigning the document type of review articles in citation index databases like Web of Science(WoS)and Scopus is important.This study aims to investigate the document type assignation of review arti... Purpose:Accurately assigning the document type of review articles in citation index databases like Web of Science(WoS)and Scopus is important.This study aims to investigate the document type assignation of review articles in Web of Science,Scopus and Publisher’s websites on a large scale.Design/methodology/approach:27,616 papers from 160 journals from 10 review journal series indexed in SCI are analyzed.The document types of these papers labeled on journals’websites,and assigned by WoS and Scopus are retrieved and compared to determine the assigning accuracy and identify the possible reasons for wrongly assigning.For the document type labeled on the website,we further differentiate them into explicit review and implicit review based on whether the website directly indicates it is a review or not.Findings:Overall,WoS and Scopus performed similarly,with an average precision of about 99% and recall of about 80%.However,there were some differences between WoS and Scopus across different journal series and within the same journal series.The assigning accuracy of WoS and Scopus for implicit reviews dropped significantly,especially for Scopus.Research limitations:The document types we used as the gold standard were based on the journal websites’labeling which were not manually validated one by one.We only studied the labeling performance for review articles published during 2017-2018 in review journals.Whether this conclusion can be extended to review articles published in non-review journals and most current situation is not very clear.Practical implications:This study provides a reference for the accuracy of document type assigning of review articles in WoS and Scopus,and the identified pattern for assigning implicit reviews may be helpful to better labeling on websites,WoS and Scopus.Originality/value:This study investigated the assigning accuracy of document type of reviews and identified the some patterns of wrong assignments. 展开更多
关键词 Document type Web of science sCOPUs Review article
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Snapshot Survey of the Presence of Perfluoroalkyl Substances in Products, Articles, and the Environment in Ecuador
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作者 Heidelore Fiedler Luis Vega-Bustillos +2 位作者 Jenny Arias-Pastrano Lander Vinicio Pérez-Aldás Jose Castro-Díaz 《Engineering》 SCIE EI CAS CSCD 2024年第6期49-61,共13页
The Stockholm Convention on Persistent Organic Pollutants(POPs)is a legally binding instrument for 186 Parties(status:April 2023).Accordingly,among other responsibilities,countries are obliged to report the production... The Stockholm Convention on Persistent Organic Pollutants(POPs)is a legally binding instrument for 186 Parties(status:April 2023).Accordingly,among other responsibilities,countries are obliged to report the production,import,or export of the POPs listed in Annexes A,B,or C;provide information to registers;maintain inventories;and monitor the presence of POPs in the environment.In the broader context of international chemicals and waste management,producer responsibilities,harmonized reporting,and compliance with national and international regulations,Ecuador has addressed the newly listed group of perfluorinated alkyl substances(PFAS)in its national implementation plan and sent selected products from its national market for PFAS analysis.The products analyzed came from the initially listed fields of specific exemptions and acceptable purposes,including:fire-fighting foams;photographic aids;greasers/degreasers;various kinds of paper/packaging;textiles;and leather,coatings,cleaners,metal plating,and pesticides.Our results showed that the three PFAS presently listed in the Stockholm Convention could be quantified in only a few samples;additional PFAS,not yet listed in the Convention also had low detection frequencies.Although the number of samples was limited,the samples covered a large spectrum of sample matrices,making it possible to conclude that—once these products become waste and are regulated under the Basel Convention—they would not constitute a disposal problem.Nevertheless,verification of the presence of PFAS in products on the market is expected to pose an analytical challenge for both,developed and developing countries. 展开更多
关键词 Emerging or newly listed POPs stockholm Convention Products and articles PFAs analysis Developing countries
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Controllable fabrication of FeCoS_(4) nanoparticles/S-doped bowl-shaped hollow carbon as efficient lithium storage anode
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作者 Ming Zhou Mengrong Wu +8 位作者 Haiwei Yu Xiangjun Zheng Kuan Shen Xingmei Guo Yuanjun Liu Fu Cao Hongxing Gu Qinghong Kong Junhao Zhang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第3期78-88,共11页
To address the low conductivity and easy agglomeration of transition metal sulfide nanoparticles,FeCoS_(4) nanoparticles embedded in S-doped hollow carbon(FeCoS_(4)@S-HC)composites were successfully fabricated through... To address the low conductivity and easy agglomeration of transition metal sulfide nanoparticles,FeCoS_(4) nanoparticles embedded in S-doped hollow carbon(FeCoS_(4)@S-HC)composites were successfully fabricated through a combination of hydrothermal processes and sulfidation treatment.The unique bowlshaped FeCoS_(4)/S-HC composites exhibit excellent structural stability with a high specific surface area of 303.7 m^(2)·g^(-1) and a pore volume of 0.93 cm^(3)·g^(-1).When applied as anode material for lithium-ion batteries,the FeCoS_(4)@S-HC anode exhibits efficient lithium storage with high reversible specific capacity(970.2 mA·h·g^(-1) at 100 mA·g^(-1))and enhanced cycling stability(574 mA·h·g^(-1) at 0.2 A·g^(-1) after 350 cycles,a capacity retention of 84%).The excellent lithium storage is attributed to the fact that the bimetallic FeCoS_(4) nanoparticles with abundant active sites can accelerate the electrochemical reaction kinetics,and the bowl-shaped S-HC structure can provide a stable mechanical structure to suppress volume expansion. 展开更多
关键词 Bimetallic sulfides Bowl-shaped hollow carbon s doping Buffering volume expand Lithium-ion batteries
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Preparation of 20 (S)-protopanaxadiol PLGA Nanoparticles
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作者 Tao PAN Baifang GONG +2 位作者 Zhixia WANG Hanyu SUN Xuanle YIN 《Medicinal Plant》 2024年第1期13-17,共5页
[Objectives]To prepare 20(S)-protopanaxadiol PLGA nanoparticles(20(S)-PPD-PLGA-NPs).[Methods]20(S)-PPD-PLGA-NPs were prepared by emulsion solvent evaporation method,and the optimal formulation was screened by Box-Behn... [Objectives]To prepare 20(S)-protopanaxadiol PLGA nanoparticles(20(S)-PPD-PLGA-NPs).[Methods]20(S)-PPD-PLGA-NPs were prepared by emulsion solvent evaporation method,and the optimal formulation was screened by Box-Behnken experiment with particle size and drug loading as the indicators through single factor experiment,and the drug release in vitro was carried out.[Results]The average diameter of the nanoparticles was(119.60±2.29)nm and the polydispersity index was(0.12±0.02),the size was uniform.The encapsulation efficiency and drug loading of protopanaxadiol were(87.99±1.29)%and(14.86±0.25)%,respectively.[Conclusions]The 20(S)-PPD-PLGA-NPs were successfully prepared by emulsion solvent evaporation method,and the 20(S)-PPD-PLGA-NPs had good stability,to lay a foundation for the study of 20(S)-PPD-PLGA-NPs in vitro and in vivo. 展开更多
关键词 20(s)-protopanaxadiol PLGA nanoparticles Emulsion solvent evaporation method
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Ultralong nitrogen/sulfur Co-doped carbon nano-hollowsphere chains with encapsulated cobalt nanoparticles for highly efficient oxygen electrocatalysis 被引量:5
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作者 Wei Zhang Xingmei Guo +6 位作者 Cong Li Jiang-Yan Xue Wan-Ying Xu Zheng Niu Hongwei Gu Carl Redshaw Jian-Ping Lang 《Carbon Energy》 SCIE CSCD 2023年第8期15-30,共16页
The development of simple and effective strategies to prepare electrocatalysts,which possess unique and stable structures comprised of metal/nonmetallic atoms for oxygen reduction reaction(ORR)and oxygen evolution rea... The development of simple and effective strategies to prepare electrocatalysts,which possess unique and stable structures comprised of metal/nonmetallic atoms for oxygen reduction reaction(ORR)and oxygen evolution reaction(OER),is currently an urgent issue.Herein,an efficient bifunctional electrocatalyst featured by ultralong N,S-doped carbon nano-hollow-sphere chains about 1300 nm with encapsulated Co nanoparticles(Co-CNHSCs)is developed.The multifunctional catalytic properties of Co together with the heteroatom-induced charge redistribution(i.e.,modulating the electronic structure of the active site)result in superior catalytic activities toward OER and ORR in alkaline media.The optimized catalyst Co-CNHSC-3 displays an outstanding electrocatalytic ability for ORR and OER,a high specific capacity of 1023.6 mAh gZn^(-1),and excellent reversibility after 80 h at 10mA cm^(-2)in a Zn-air battery system.This work presents a new strategy for the design and synthesis of efficient multifunctional carbon-based catalysts for energy storage and conversion devices. 展开更多
关键词 Co nanoparticles N s co-doping oxygen electrocatalysts rechargeable Zn-air batteries ultralong carbon nano-hollow-sphere chains
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Topic Models to Analyze Disaster-Related Newspaper Articles: Focusing on COVID-19
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作者 Yun-Jung Choi Youn-Joo Um 《International Journal of Mental Health Promotion》 2023年第3期421-431,共11页
Major media outlets have run many articles on the COVID-19 pandemic.Since the public suffers cognitive and emotional effects related to COVID-19 from such reports,we analyzed and reviewed the topics of news reports.We... Major media outlets have run many articles on the COVID-19 pandemic.Since the public suffers cognitive and emotional effects related to COVID-19 from such reports,we analyzed and reviewed the topics of news reports.We searched newspaper articles with the term‘COVID-19’term in four Korean daily newspapers from January 20,2020,when thefirst patient in Korea was found,to June 15,2020.Topic modeling analysis was conducted through text mining using R.Five themes were found:“Changes in people’s everyday life,”“Socio-economic shock,”“Trends in infection,”“Role of the government and business,”and“Increased psychological anxiety,”which all showed sharp increases in articles from mid-February to early March and then decreased.Despite the increased psychological anxiety people suffered from the COVID-19 pandemic,this topic showed the fewest articles.“Changes in people’s everyday life”showed the most,focusing attention on stimulating lifestyle articles of general interest.Since the COVID-19 pandemic can lead to mental health problems due to severe changes and isolation in everyday life,a comprehensive response to the news focusing on the impact on the mental health of the population around the world should be made. 展开更多
关键词 COVID-19 mental health newspaper article text mining
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Rationally designed hollow carbon nanospheres decorated with S,P co-doped NiSe_(2) nanoparticles for high-performance potassium-ion and lithium-ion batteries 被引量:3
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作者 Jiajia Ye Zizhong Chen +4 位作者 Zhiqiang Zheng Zhanghua Fu Guanghao Gong Guang Xia Cheng Hu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第3期401-411,I0011,共12页
Hollow nanostructures with external shells and inner voids have been proved to greatly shorten the transport distance of ions/electrons and buffer volume change,especially for the large-sized potassium-ions in seconda... Hollow nanostructures with external shells and inner voids have been proved to greatly shorten the transport distance of ions/electrons and buffer volume change,especially for the large-sized potassium-ions in secondary batteries.In this work,hollow carbon(HC) nanospheres embedded with S,P co-doped NiSe_(2)nanoparticles are fabricated by "drop and dry" and "dissolving and precipitation" processes to form Ni(OH)2nanocrystals followed by annealing with S and P dopants to form nanoparticles.The resultant S,P-NiSe_(2)/HC composite exhibits excellent cyclic performance with 131.6 mA h g^(-1)at1000 mA g^(-1)after 3000 cycles for K^(+)storage and a capacity of 417.1 mA h g^(-1)at 1000 mA g^(-1)after1000 cycles for Li^(+)storage.K-ion full cells are assembled and deliver superior cycling stability with a ca pacity of 72.5 mA h g^(-1)at 200 mA g^(-1)after 500 cycles.The hollow carbon shell with excellent electrical conductivity effectively promotes the transporta tion and tolerates large volume variation for both K^(+)and Li^(+).Density functional theory calculations confirm that the S and P co-doping NiSe_(2) enables stronger adsorption of K^(+)ions and higher electrical conductivity that contributes to the improved electrochemical performance. 展开更多
关键词 s P co-doping Nise_(2)nanoparticles Hollow carbon nanospheres Potassium-ion batteries Lithium-ion batteries
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In Situ Generation of Copper Nanoparticles in Heat-Treated Copper-Containing Masson’s Pine as a Preservative Process for Sawn Timber
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作者 Minting Lai Guijun Xie +2 位作者 Wanju Li Lamei Li Yongjian Cao 《Journal of Renewable Materials》 SCIE EI 2023年第6期2665-2678,共14页
Heat-treated wood has good dimensional stability,durability,and color,but its susceptibility to fungal growth affects its commercial value.In this study,lumber harvested from mature Masson’s pine(Pinus massoniana Lam... Heat-treated wood has good dimensional stability,durability,and color,but its susceptibility to fungal growth affects its commercial value.In this study,lumber harvested from mature Masson’s pine(Pinus massoniana Lamb.)was vacuum impregnated with a basic copper salt solution(copper hydroxide,diethanolamine,and polyethylene glycol 200)prior to heat-treatment at 220℃ for 3 h.Antifungal properties,surface chemistry,crystal structure and sugar contents were tested,compared with heat treatment alone.The results showed that the samples treated by heating without copper salt treatment showed poor suppression of fungal growth,the copperimpregnated heat-treated wood suppressed(100%)the growth of Botryodiplodia theobromae Pat.,Aspergillus niger V.Tiegh.,Penicillium citrinum Thom,and Trichoderma viride Pers.The combined results of X-ray photoelectron spectroscopy,X-ray diffraction and sugars analysis suggested that fungal inhibition by the heat-treated copper-bearing Masson’s pine was mainly due to the reduction of the metal salt by PEG200 at high temperature to generate copper nanoparticles.In addition,the reduced sugar content of the treated timber,and hence the nutrient substrate for spoilage microbes,reduced in the presence of the metal salts at high-temperature.This study has demonstrated an effective method of increasing low-grade wood’s utility and commercial value. 展开更多
关键词 Heat treatment Masson’s pine sawn timber inhibition of fungal growth copper nanoparticles
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Application of the Shrinking Particle Model for the Evaluation of Molecular Recyclability of PET versus Semi-Aromatic Polyesters
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作者 Jack van Schijndel Sanne de Krom +2 位作者 Dennis Molendijk Koen van Beurden Amarante Böttger 《Open Journal of Physical Chemistry》 2024年第2期21-35,共15页
The molecular recyclability of poly (ethylene terephthalate) (PET) and three semi-aromatic polyesters poly (phloretic acid) (poly-H), poly (dihydroferulic acid) (poly-G), and poly (dihydrosinapinic acid) (poly-S) is e... The molecular recyclability of poly (ethylene terephthalate) (PET) and three semi-aromatic polyesters poly (phloretic acid) (poly-H), poly (dihydroferulic acid) (poly-G), and poly (dihydrosinapinic acid) (poly-S) is evaluated in this study. PET is an extensively used aromatic polyester, and poly-H, poly-G, and poly-S can be considered semi-aromatic poly (lactic acid) modifications. All these polyesters have been depolymerized at neutral pH and by acid- and base-catalyzed hydrolysis at two temperatures, i.e., 50˚C and 80˚C. Base-catalyzed depolymerization of virgin PET leads to an isolated yield of 38% after 48 hours of reaction at 80˚C. Contrary to these results for PET, almost all the monomers of the semi-aromatic polyesters poly-H, poly-G, and poly-S are recovered with isolated yields larger than 90% at the same temperature after 15 minutes in a facile manner. A shrinking particle model used to determine the global kinetics of the base-catalyzed depolymerization showed that the rate rises with increasing temperature. Using the shrinking particle model, the intrinsic reaction rate constants were determined. It has been demonstrated that the rate coefficients of the depolymerization of the semi-aromatic polyesters poly-H, poly-G, and poly-S are between 2 and 3 orders of magnitude higher than those for PET. 展开更多
关键词 DEPOLYMERIZATION Molecular Recycling Poly-H Poly-G Poly-s PET Circular Polymers
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Dark Matter Particles
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作者 Vladimir S. Netchitailo 《Journal of High Energy Physics, Gravitation and Cosmology》 2023年第4期1004-1020,共17页
Researchers have been able to infer the existence of Dark Matter (DM) only from the gravitational effect. DM seems to outweigh visible matter roughly six to one, making up about 27% of the universe. Here’s a sobering... Researchers have been able to infer the existence of Dark Matter (DM) only from the gravitational effect. DM seems to outweigh visible matter roughly six to one, making up about 27% of the universe. Here’s a sobering fact: The matter we know and that makes up all stars and galaxies only accounts for 5% of the content of universe! But what is DM? [1]. Many experiments to detect and study Dark Matter Particles (DMPs) directly are being actively undertaken, but none have yet succeeded. Indirect detection experiments search for the products of the annihilation or decay of DMPs in outer space [2]. In this paper, we discuss main ideas of the Hypersphere World-Universe Model (WUM) and introduce an additional new DMP “XION” (boson) with the rest energy 10.6 μeV that is an analog of Axion. On June 28, 2023, it was announced the existence of Cosmic Gravitational Background. In frames of WUM, we give an explanation of this discovery based on the analysis of “Gravitoplasma” composed of objects with Planck mass, which were created as the result of Weak Interaction between XIONs and other particles in the Medium. 展开更多
关键词 World-Universe Model Multicomponent Dark Matter Multiworld Planck Mass XION Cosmic Gravitational Background Distribution of World’s Energy Density
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Top 50 most cited articles on prostatic artery embolization for benign prostatic hyperplasia:A bibliometric review
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作者 Christopher Thomas Zoppo Trenton Taros Aaron Harman 《World Journal of Clinical Urology》 2023年第1期1-9,共9页
BACKGROUND Bibliometric analysis can be used to assess the current state of the literature and publication trends on a given topic.There has not been a review of this kind on prostatic artery embolization(PAE)for beni... BACKGROUND Bibliometric analysis can be used to assess the current state of the literature and publication trends on a given topic.There has not been a review of this kind on prostatic artery embolization(PAE)for benign prostatic hyperplasia(BPH).PAE is a relatively new and somewhat controversial treatment option for BPH.Given the novelty and controversy,there has been much research published on the topic recently.AIM To survey the current state of research on PAE for BPH by using bibliometric analysis to analyze the top 50 most highly cited articles.METHODS A cross-sectional study was performed using the Web of Science database to identify the most cited articles published on PAE for BPH as of June 2022.Articles that did not primarily focus on PAE or BPH as an indication were eliminated.The 50 most cited articles were carried forward for analysis.RESULTS All but 6 articles were published in the last decade with contributions from 15 countries.Fifty-two percent of the studies had a C level of evidence.The majority were published in the Journal of Vascular and Interventional Radiology and Cardiovascular and Interventional Radiology.Twenty percent(n=10)of the articles were published in urologic journals.On average,articles published in urologic journals tended to be more recent.The mean year of publication for an article in a urological journal was 2016.6 compared to 2013.9 in a non-urologic journal(P=0.02).Seventy percent of the articles focused on clinical outcomes,while only 2%focused on practice guidelines.Self-citations accounted for 11.4 citations perarticle on average,corresponding to 14.7%of all citations analyzed.CONCLUSION The most influential papers on this topic represent a fairly recent body of work with contributions from a wide variety of countries and journals.The fact that articles in urologic journals were published significantly more recently than articles on the list in non-urologic journals may suggest that the field of urology is starting to accept PAE for a wider range of indications.Finally,while there has been much high-quality research published,more influential studies on practice guidelines and technique may be beneficial. 展开更多
关键词 Prostate artery embolization Benign prostatic hyperplasia Endovascular urology Bibliometric review©The Author(s)2023.Published by Baishideng Publishing Group Inc.All rights reserved.
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2022年四川芦山M_(S)6.1地震前应力状态研究
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作者 张致伟 曾宪伟 +4 位作者 王迪 路茜 王玮铭 杨鹏 龙锋 《地震研究》 CSCD 北大核心 2024年第4期483-492,共10页
为研究2022年6月1日四川芦山M_(S)6.1地震的孕育和发生过程,采用CAP方法反演了2013年芦山M_(S)7.0主震及M_(S)≥5.0余震的震源机制解,并基于应力张量方差与b值时空分布特征,探讨了芦山M_(S)6.1地震的力学机制和震源区的应力状态。结果表... 为研究2022年6月1日四川芦山M_(S)6.1地震的孕育和发生过程,采用CAP方法反演了2013年芦山M_(S)7.0主震及M_(S)≥5.0余震的震源机制解,并基于应力张量方差与b值时空分布特征,探讨了芦山M_(S)6.1地震的力学机制和震源区的应力状态。结果表明:2022年芦山M_(S)6.1地震震源机制表现出与2013年芦山M_(S)7.0主震和5级余震相似的逆冲型破裂特征,压应力轴方位与龙门山断裂带南段区域应力场一致。2013年芦山M_(S)7.0地震后震中及附近的应力张量方差和b值长期处于低值状态,2022年芦山M_(S)6.1地震前震中及附近出现了应力张量方差和b值的低值异常,表明芦山余震区处于较高的应力水平。分析认为:巴颜喀拉块体持续东向运动受到华南块体的阻挡,震中所在区域长期受挤压逆冲作用,从而使芦山余震区长期处于应力积累的状态,芦山M_(S)6.1地震也是在这种动力学背景下发生的。 展开更多
关键词 芦山M_(s)6.1地震 芦山M_(s)7.0地震 震源机制解 应力张量方差 B值 应力状态
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Fuzzy Words Distribution in Management Science Research Articles 被引量:1
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作者 董艳云 白永权 蒋跃 《Sino-US English Teaching》 2007年第3期37-42,共6页
By using ZHANG Qiao's method for identifying fuzzy words (1998), the present paper makes a statistic analysis of fuzzy words appearing in about 43,000 words of 6 academic research articles in management science. A ... By using ZHANG Qiao's method for identifying fuzzy words (1998), the present paper makes a statistic analysis of fuzzy words appearing in about 43,000 words of 6 academic research articles in management science. A distribution curve of fuzzy words in management research articles is drawn in accordance with the structures of the articles, and it is proved to be reasonable for tile discourse function of each section. Furthermore, the fuzzy words are divided into three categories and eleven sub-categories, including Category Ⅰ-fuzzy words, Category Ⅱ-fuzzy words+non-fuzzy part / non-fuzzy part+fuzzy words, Category Ⅲ-approximators+fuzzy words. Distribution of fuzzy words varies in different sections of research articles in management science, because of different communicative purposes or discourse functions. Introduction section and Conclusion section have a higher occurrence rate of fuzzy words than Abstract section and Methodology and Data section. 展开更多
关键词 academic research articles in management science fuzzy words distribution curve discourse function category research
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阴道卷曲乳杆菌S层蛋白多样性研究
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作者 李娜 刘好静 +2 位作者 张婷 张茜 李娇 《川北医学院学报》 CAS 2024年第9期1167-1170,1175,共5页
目的:分析比较西安市女性阴道卷曲乳杆菌S层蛋白的多样性及NCBI数据库中阴道来源卷曲乳杆菌S层蛋白的多样性。方法:选取100例妇科患者的阴道分泌物标本作为研究对象,从其中10例标本中分离得到480株卷曲乳杆菌,其中两株卷曲乳杆菌S层蛋... 目的:分析比较西安市女性阴道卷曲乳杆菌S层蛋白的多样性及NCBI数据库中阴道来源卷曲乳杆菌S层蛋白的多样性。方法:选取100例妇科患者的阴道分泌物标本作为研究对象,从其中10例标本中分离得到480株卷曲乳杆菌,其中两株卷曲乳杆菌S层蛋白有明显差异,对其进行全基因组测序;并从NCBI数据库中下载人阴道源的卷曲乳杆菌全基因组数据,分析并比较西安市来源与数据库来源的卷曲乳杆菌S层蛋白的多样性。结果:S层蛋白注释基因具有菌株内和菌株间的多样性,同一套基因组中有多个S层蛋白注释基因,菌株间的相似性偏差较大,通过系统发育分析发现,中国人阴道卷曲乳杆菌的S层蛋白基因与其他人种的具有系统发育相似性。结论:阴道卷曲乳杆菌S层蛋白具有菌种间和菌株间多样性的特征,不同人种的卷曲乳杆菌具有相似性。 展开更多
关键词 阴道 卷曲乳杆菌 s层蛋白 多样性
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献血者HBVs基因变异的生物信息学分析
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作者 范加诚 李青 +2 位作者 陈秀丽 刘世香 陈烨 《中国输血杂志》 CAS 2024年第8期933-939,共7页
目的分析HBV DNA+/HBsAg-献血者的传染性指标、S区基因序列突变情况及生物信息学特征变化。方法通过PCR方法筛查出1份HBV DNA+/HBsAg-的标本,应用酶联免疫和化学发光方法检测该标本乙肝病毒5项指标,对该标本HBVs区基因片段测序并分析变... 目的分析HBV DNA+/HBsAg-献血者的传染性指标、S区基因序列突变情况及生物信息学特征变化。方法通过PCR方法筛查出1份HBV DNA+/HBsAg-的标本,应用酶联免疫和化学发光方法检测该标本乙肝病毒5项指标,对该标本HBVs区基因片段测序并分析变异情况,应用分析软件对所测序列进行生物信息学分析。结果该标本HBV DNA+、HBsAg-、HBsAb+、HBeAg+、HBeAb-、HBcAb+;HBVs区基因序列内发生氨基酸单位点突变(P151L),空间结构发生改变。结论HBVs区基因序列空间结构改变,可能是导致检测结果出现血清学HBsAg-/HBsAb+/HBV DNA+的原因。 展开更多
关键词 HBV OBI s基因 献血者 生物信息学
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基于数值模拟的高速公路S型曲线积水规律分析
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作者 吴文亮 曾威凯 +1 位作者 李智 王晓飞 《华南理工大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第8期56-64,共9页
S型曲线由于特殊的线型几何特征形成了易积水的路面区域,对于积水规律的掌握有利于在设计和建造阶段提前预防和处理积水路段的危害。该文基于计算流体力学软件Fluent,结合计算流体力学分析中基于欧拉-拉格朗日方法的欧拉液膜模型EWF(Eul... S型曲线由于特殊的线型几何特征形成了易积水的路面区域,对于积水规律的掌握有利于在设计和建造阶段提前预防和处理积水路段的危害。该文基于计算流体力学软件Fluent,结合计算流体力学分析中基于欧拉-拉格朗日方法的欧拉液膜模型EWF(Eulerian Wall Film),针对精细化处理的典型S型曲线双向多车道道路模型进行模拟计算。模拟包含了几何特征与降雨量等不同变量因素,得出了积水的水膜厚度以及流速分布规律。模拟结果表明:在降雨阶段,S型曲线横坡坡度0%~1%路段为积水路段,横坡坡度1%~2%路段为易积水路段,横坡坡度大于2%的路段积水情况受到降雨强度影响;在排水阶段,S型曲线横坡坡度0%~1%路段为排水困难路段,横坡坡度1%~2%路段为排水不畅路段,横坡坡度大于2%的路段排水顺畅,在排水时间结束时,路面在不同的几何条件和降雨条件下均能将积水排除至水膜厚度小于2 cm,横坡的大小与渐变影响了积水的横向分布与纵向分布,横向呈现中间高两边低、横断面上标高大的位置水膜厚度小和标高小的位置水膜厚度大的水膜厚度分布规律,总体呈现S型的分布规律;水膜流速在积水阶段呈现纵向上中间低两边高、水膜厚度大则水膜流速大的水膜厚度分布规律,在排水阶段则为纵向上中间高两边低的水膜流速分布规律。道路宽度影响了降雨落到路面的积水总量,进而对积水水膜厚度产生了影响;超高缓和率则主要使得积水路段、易积水路段增长,从而影响了积水分布的范围。 展开更多
关键词 计算流体力学 s型曲线 路面积水 积水规律
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S31603复合板压力容器点蚀行为试验研究 被引量:1
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作者 宋晓俊 杨忠武 +4 位作者 豆磊 张烜玮 魏西尧 谭中炜 郭睿朋 《压力容器》 北大核心 2024年第3期8-16,共9页
针对S31603复合板压力容器不锈钢层不同点蚀深度的发展进程及穿透至碳钢层后的电偶腐蚀风险,通过预制不同点蚀深度的S31603复合板试片组,分别在实验室和现场S31603复合板压力容器内进行腐蚀试验,并对试片进行宏观分析、低倍观察、高倍... 针对S31603复合板压力容器不锈钢层不同点蚀深度的发展进程及穿透至碳钢层后的电偶腐蚀风险,通过预制不同点蚀深度的S31603复合板试片组,分别在实验室和现场S31603复合板压力容器内进行腐蚀试验,并对试片进行宏观分析、低倍观察、高倍观察及腐蚀产物表征分析。结果表明,S31603复合板预制的点蚀坑深度穿透至碳钢层时发生了明显的电偶腐蚀,实验室腐蚀试验和现场试验最高点蚀速率分别达到4.954,1.023 mm/a;用S31603复合板试片预制的点蚀坑深度穿透至碳钢层后碳钢优先发生电偶腐蚀;S31603复合板试片预制的点蚀坑深度处于不锈钢层时腐蚀轻微,也未萌生新的点蚀,相邻点蚀坑之间也未见明显的腐蚀影响。在含Cl-的酸性腐蚀性介质环境下,当S31603复合板压力容器点蚀深度处于不锈钢层时腐蚀轻微,当点蚀深度穿透至碳钢层后,会发生明显的电偶腐蚀,需要缩短S31603复合板压力容器开罐检修周期以保证安全使用。 展开更多
关键词 复合板压力容器 点蚀 s31603 腐蚀试验
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深水采油树Spring-Seal密封圈接触模型构建与实验测试
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作者 张红 龙圣均 +1 位作者 冯定 黄熠 《中国安全生产科学技术》 CAS CSCD 北大核心 2024年第8期112-119,共8页
为提高深水采油树在高压、高温、低温等工况下长时间工作的稳定性,对采油树密封圈进行重新设计,提出Spring-Seal密封圈(以下简称S密封圈);基于赫兹接触理论、填料密封接触理论,重新构建S密封圈接触力学模型;建立有限元仿真分析模型,分... 为提高深水采油树在高压、高温、低温等工况下长时间工作的稳定性,对采油树密封圈进行重新设计,提出Spring-Seal密封圈(以下简称S密封圈);基于赫兹接触理论、填料密封接触理论,重新构建S密封圈接触力学模型;建立有限元仿真分析模型,分析不同条件下S密封圈的密封性能,同时验证新建接触模型的合理性;利用实验测试S密封圈的实际密封效果。研究结果表明:S密封圈在高压、高温、低温等工况下能够长时间稳定工作且密封性能良好。研究结果可为S密封圈的接触研究及工程运用提供理论参考。 展开更多
关键词 s密封圈 接触模型 密封性能 实验
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妊娠糖尿病患者蛋白C、蛋白S和抗凝血酶Ⅲ水平及其与孕周的关系
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作者 王全先 代延朋 +5 位作者 丁燕子 付梦宇 张雪薇 邢金芳 董凯楠 袁恩武 《河南医学研究》 CAS 2024年第8期1362-1365,共4页
目的探讨妊娠糖尿病(GDM)患者蛋白C(PC)、蛋白S(PS)和抗凝血酶Ⅲ(ATⅢ)水平及其与孕周的关系。方法选择2019年1月至2023年3月在医院就诊的232例GDM孕妇作为观察组,同时随机选取同期在医院进行孕检的268例正常孕妇作为对照组,比较两组一... 目的探讨妊娠糖尿病(GDM)患者蛋白C(PC)、蛋白S(PS)和抗凝血酶Ⅲ(ATⅢ)水平及其与孕周的关系。方法选择2019年1月至2023年3月在医院就诊的232例GDM孕妇作为观察组,同时随机选取同期在医院进行孕检的268例正常孕妇作为对照组,比较两组一般资料和PC、PS和ATⅢ水平;按孕周将观察组和对照组分为孕中期和孕晚期,分别比较孕中期和孕晚期观察组和对照组PC、PS和ATⅢ水平。通过相关性分析,分析PC、PS和ATⅢ水平与孕周的相关性。结果与对照组相比,观察组PS和PC水平降低(P<0.05),但ATⅢ水平差异无统计学意义(P>0.05)。GDM患者PC和ATⅢ水平与孕周呈负相关(r=-0.156、-0.134,P<0.05)。结论GDM患者PS和PC水平降低,且随孕周增大,PC、PS和ATⅢ水平降低,应尽早进行干预,以减少血栓形成的风险。 展开更多
关键词 妊娠糖尿病 蛋白C 蛋白s 抗凝血酶Ⅲ
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