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The Impact of User-Generated Content in the Product Management Process of Digital Games
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作者 Judith Gerlach Daniel Schultheiss Anja Solf 《通讯和计算机(中英文版)》 2011年第10期855-862,共8页
关键词 数字游戏 管理过程 用户 客户忠诚度 客户满意度 顾客忠诚 产品 顾客满意
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The Influence of TikTok User-Generated Content Short Videos on Tourists’Willingness to Engage in Rural Tourism:The Mediating Role of Destination Image Perception
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作者 WANG Yang YAN Wei +1 位作者 SUN Jingru ZHOU Mi 《Journal of Resources and Ecology》 2025年第4期1185-1195,共11页
Rural tourism plays a crucial role in driving the sustainable development of rural economies.With the rise of the digital economy,user-generated content(UGC)videos on platforms such as TikTok have become a significant... Rural tourism plays a crucial role in driving the sustainable development of rural economies.With the rise of the digital economy,user-generated content(UGC)videos on platforms such as TikTok have become a significant factor influencing consumer decision-making,creating new opportunities for the growth of rural tourism.Using the TikTok app as the research platform,this study examines the relationship between UGC short videos,tourists’intentions to engage in rural tourism,and their perception of destination image.Specifically,it explores the impact of UGC short videos on tourists’willingness to participate in rural tourism and the mediating role of destination image perception.The findings indicate that UGC short videos positively influence tourists’willingness to engage in rural tourism.Destination image perception mediates this relationship,shaping tourists’decisions through cognitive and emotional image perceptions.Based on these findings,this paper recommends rural tourism destination managers enhance promotional strategies and improve destination image perception through UGC short video content. 展开更多
关键词 TikTok user-generated content short videos rural tourism intention destination image perception
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Personalized topic modeling for recommending user-generated content
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作者 Wei ZHANG Jia-yu ZHUANG +3 位作者 Xi YONG Jian-kou LI Wei CHEN Zhe-min LI 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2017年第5期708-718,共11页
User-generated content(UGC) such as blogs and twitters are exploding in modern Internet services. In such systems, recommender systems are needed to help people filter vast amount of UGC generated by other users. Howe... User-generated content(UGC) such as blogs and twitters are exploding in modern Internet services. In such systems, recommender systems are needed to help people filter vast amount of UGC generated by other users. However, traditional recommendation models do not use user authorship of items. In this paper, we show that with this additional information, we can significantly improve the performance of recommendations. A generative model that combines hierarchical topic modeling and matrix factorization is proposed. Empirical results show that our model outperforms other state-of-the-art models, and can provide interpretable topic structures for users and items. Furthermore, since user interests can be inferred from their productions, recommendations can be made for users that do not have any ratings to solve the cold-start problem. 展开更多
关键词 user-generated content(UGC) Collaborative filtering(CF) Matrix factorization(MF) Hierarchical topic modeling
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Content validation of the Global Adolescent and Child Physical Activity Questionnaire(GAC-PAQ)in low-,middle-,and high-income countries across 6 continents
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作者 Richard Larouche Saulo Neves de Oliveira +45 位作者 Mahdi Rostami Haji Abadi Judy K.Benavides-Castro Olga L.Sarmiento Garazi Angulo Garay Gabriela Argumedo Joseph O.Ashaolu Ameneh Baghestani Jasmin Bhawra Javier Brazo-Sayavera Nutnaree Choonak Christine Delisle Nystrom Seth Evance Zdenek Hamrik Alejandra Jáuregui Piyakrita Kaewpikul Piyawat Katewongsa Anuradha Khadilkar Geoff Kira McPherry Kuntembwe Yang Liu Marie Lof Tom Loney Maria Lundgren Rubina Mandlik Martine Matapo-Kolisko Chidvilas More Tawonga W.Mwase-Vuma Nattaporn Nilwatta Adewale L.Oyeyemi Susan Paudel Nanthawan Pomkai Justin Richards Diego Augusto Santos Silva Melody Smith Narayan Subedi Dyah Anantalia Widyastari Oliver W.A.Wilson SaloméAubert Valerie Carson Rachel C.Colley Dale W.Esliger Nicholas Kuzik Taru Manyanga John J.Reilly Leigh M.Vanderloo Mark S.Tremblay 《Journal of Sport and Health Science》 2026年第2期52-67,共16页
Background:Investigators from low-,middle-,and high-income countries representing 6 continents contributed to the development of the Global Adolescent and Child Physical Activity Questionnaire(GAC-PAQ).The GAC-PAQ is ... Background:Investigators from low-,middle-,and high-income countries representing 6 continents contributed to the development of the Global Adolescent and Child Physical Activity Questionnaire(GAC-PAQ).The GAC-PAQ is designed to assess physical activity(PA)across all key domains(i.e.,school,chores,work/volunteering,transport,free time,outdoor time).It aimed to address multiple gaps in global PA surveillance(e.g.,omission of important PA domains,insufficient cultural adaptation,underrepresentation of rural areas in questionnaire validation studies).The purpose of this study was to assess the content validity of the GAC-PAQ among PA experts,8-to 17-year-olds,and one of their parents/guardians,and to discuss changes made to the questionnaire based on participants'feedback.Methods:Sixty-two experts in PA measurement and/or surveillance from 24 countries completed an online survey that included both closed-and open-ended questions about the content validity of the GAC-PAQ.The proportion of experts who agreed or strongly agreed with the items was calculated.Child-parent/guardian dyads from 15 countries(n=250;10-40 per country)participated in a structured cognitive interview to assess the clarity of the questions and response options,and they were encouraged to provide suggestions to improve clarity and facilitate completion of the questionnaire.Participating countries are:Aotearoa New Zealand,Brazil,Canada,China,Colombia,Czech Republic,India,Malawi,Mexico,Nepal,Nigeria,Spain,Sweden,Thailand,and the United Arab Emirates.Interviews were conducted in 13 different languages and structured by PA domain.Generic images were included to help participants in answering questions about PA intensity.Results:Expert agreement with the items for each domain exceeded 75%,and their qualitative feedback was used to revise the questionnaire before cognitive interviews.In general,participants found the questionnaire to be comprehensive.Adolescents(12-17 years)found it easier than children(8-11 years)to answer the questions.Several children struggled to answer questions about the duration and intensity of activities and/or concepts related to travel modes,active trips,and organized activities.Many parents/guardians were unsure about the frequency,duration,and intensity of their children's or adolescents'PA at school and/or recommended using more culturally relevant and appropriate images.Some participants misunderstood the concept of activities that“make you stronger”(intended to assess resistance activities)and/or struggled to differentiate between work,volunteering,and chores.Conclusion:Participants'feedback was used to develop a revised,simplified,and culturally adapted GAC-PAQ,which will be pilot-tested in all15 countries in an App that will include country-specific images and narration in local languages.Further research is needed to assess the reliability and validity of the revised GAC-PAQ. 展开更多
关键词 Measurement Surveillance content validity Global health Cultural adaptation
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Analysis of Histochemical Localization and Content Influencing Factors of Saponins in Pseudostellaria heterophylla
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作者 Huiqing PAN Yanda ZHANG +3 位作者 Zhenhua WANG Qi ZHAO Zuyun YE Xin WANG 《Medicinal Plant》 2026年第1期5-9,19,共6页
This paper provides a systematic review of the histochemical localization,content characteristics,and influencing factors of saponins in Pseudostellaria heterophylla based on an extensive literature survey.It provides... This paper provides a systematic review of the histochemical localization,content characteristics,and influencing factors of saponins in Pseudostellaria heterophylla based on an extensive literature survey.It provides an in-depth analysis and summary of the effects of biological factors,environmental conditions,agronomic practices,processing methods,and continuous cropping obstacles on the synthesis of P.heterophylla saponins,as well as their underlying mechanisms.Based on identified gaps in the current literature,future research directions and prospects are proposed.The findings of this review offer valuable insights for advancing the understanding of the saponin biosynthesis mechanisms in P.heterophylla and for enhancing its quality. 展开更多
关键词 Pseudostellaria heterophylla SAPONIN Histochemical localization content influencing factors Research progress
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Content Determination of Zhuang Medicine Sauropus spatulifolius Beille from Guangxi
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作者 Lixin SUN Yongshan JIN +8 位作者 Wenjing YANG Aipeng LI Yarong WEI Liangna SU Chengxu CHEN Fangyuan SHEN Yanmin LU Suoyi HUANG Lixiang LU 《Medicinal Plant》 2026年第1期1-4,共4页
[Objectives]To determine the content of Zhuang medicine Sauropus spatulifolius Beille from Guangxi.[Methods]The amino acid content of S.spatulifolius Beille was determined by ultraviolet spectrophotometry(UVs).The con... [Objectives]To determine the content of Zhuang medicine Sauropus spatulifolius Beille from Guangxi.[Methods]The amino acid content of S.spatulifolius Beille was determined by ultraviolet spectrophotometry(UVs).The content of kaempferol-3-O-gentiobioside in S.spatulifolius Beille was determined by liquid chromatography-mass spectrometry(LC-MS).Pesticide residues in S.spatulifolius Beille were detected by gas chromatography-mass spectrometry(GC-MS).Heavy metal elements arsenic(As),cadmium(Cd),and lead(Pb)in S.spatulifolius Beille were detected by inductively coupled plasma mass spectrometry(ICP-MS).[Results]The amino acid content in S.spatulifolius Beille was 3.233 mg/g,with a relative standard deviation(RSD)of 0.36%.The content of kaempferol-3-O-gentiobioside was 1.15μg/mL.No pesticide residues or heavy metals were detected in the S.spatulifolius Beille medicinal material.[Conclusions]This study improves the quality control system for S.spatulifolius Beille and provides a reference basis for the quality standard control of Zhuang medicine S.spatulifolius Beille from Guangxi. 展开更多
关键词 Zhuang medicine Sauropus spatulifolius Beille Liquid chromatography-mass spectrometry(LC-MS) Gas chromatography-mass spectrometry(GC-MS) Inductively coupled plasma mass spectrometry(ICP-MS) content determination
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Key techniques for precise measuring gas content in deep coal mine:In-situ pressure-and gas-preserved coring 被引量:2
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作者 Ju Li Jianan Li +4 位作者 Tianyu Wang Guikang Liu Zhiqiang He Cong Li Heping Xie 《International Journal of Mining Science and Technology》 2025年第4期589-607,共19页
Gas content serves as a critical indicator for assessing the resource potential of deep coal mines and forecasting coal mine gas outburst risks.However,existing sampling technologies face challenges in maintaining the... Gas content serves as a critical indicator for assessing the resource potential of deep coal mines and forecasting coal mine gas outburst risks.However,existing sampling technologies face challenges in maintaining the integrity of gas content within samples and are often constrained by estimation errors inherent in empirical formulas,which results in inaccurate gas content measurements.This study introduces a lightweight,in-situ pressure-and gas-preserved corer designed to collect coal samples under the pressure conditions at the sampling point,effectively preventing gas loss during transfer and significantly improving measurement accuracy.Additionally,a gas migration model for deep coal mines was developed to elucidate gas migration characteristics under pressure-preserved coring conditions.The model offers valuable insights for optimizing coring parameters,demonstrating that both minimizing the coring hole diameter and reducing the pressure difference between the coring-point pressure and the original pore pressure can effectively improve the precision of gas content measurements.Coring tests conducted at an experimental base validated the performance of the corer and its effectiveness in sample collection.Furthermore,successful horizontal coring tests conducted in an underground coal mine roadway demonstrated that the measured gas content using pressure-preserved coring was 34%higher than that obtained through open sampling methods. 展开更多
关键词 Pressure-and gas-preserved coring Deep coal mines coring Gas migration model In-situ gas content
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Enhancing Folate Content in Japonica Rice Through Co-expression of OsADCS and OsGTPCHI Indica Alleles 被引量:1
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作者 LAI Changkai HU Shikai +9 位作者 JIAO Guiai WANG Ling SHAO Gaoneng ZHAO Fengli XIE Lihong WEI Xiangjin LÜYusong SHENG Zhonghua TANG Shaoqing HU Peisong 《Rice science》 2025年第3期353-366,I0050-I0058,共23页
Rice is a poor source of folate,an essential micronutrient for the body.Biofortification offers an effective way to enhance the folate content of rice and alleviate folate deficiencies in humans.In this study,we confi... Rice is a poor source of folate,an essential micronutrient for the body.Biofortification offers an effective way to enhance the folate content of rice and alleviate folate deficiencies in humans.In this study,we confirmed that OsADCS and OsGTPCHI,encoding the initial enzymes necessary for folate synthesis,positively regulate folate accumulation in knockout mutants of both japonica and indica rice backgrounds.The folate content in the low-folate japonica variety was slightly increased by the expression of the indica alleles driven by the endosperm-specific promoter.We further obtained co-expression lines by stacking OsADCS and OsGTPCHI genes;the folate accumulation in brown rice and polished rice reached 5.65μg/g and 2.95μg/g,respectively,representing 37.9-fold and 26.5-fold increases compared with the wild type.Transcriptomic analysis of rice grains from six transgenic lines showed that folate changes affected biological pathways involved in the synthesis and metabolism of rice seed storage substances,while the expression of other folate synthesis genes was weakly regulated.In addition,we identified Aus rice as a high-folate germplasm carrying superior haplotypes of OsADCS and OsGTPCHI through natural variation.This study provides an alternative and effective complementary strategy for rice biofortification,promoting the rational combination of metabolic engineering and conventional breeding to breed high-folate varieties. 展开更多
关键词 BIOFORTIFICATION endosperm-specific expression OsADCS OsGTPCHI folate content GRAIN Oryza sativa
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Factor analysis and machine learning for predicting endpoint carbon content in converter steelmaking 被引量:2
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作者 Lihua Zhao Shuai Yang +3 位作者 Yongzhao Xu Zhongliang Wang Xin Liu Yanping Bao 《International Journal of Minerals,Metallurgy and Materials》 2025年第10期2469-2482,共14页
The endpoint carbon content in the converter is critical for the quality of steel products,and accurately predicting this parameter is an effective way to reduce alloy consumption and improve smelting efficiency.Howev... The endpoint carbon content in the converter is critical for the quality of steel products,and accurately predicting this parameter is an effective way to reduce alloy consumption and improve smelting efficiency.However,most scholars currently focus on modifying methods to enhance model accuracy,while overlooking the extent to which input parameters influence accuracy.To address this issue,in this study,a prediction model for the endpoint carbon content in the converter was developed using factor analysis(FA)and support vector machine(SVM)optimized by improved particle swarm optimization(IPSO).Analysis of the factors influencing the endpoint carbon content during the converter smelting process led to the identification of 21 input parameters.Subsequently,FA was used to reduce the dimensionality of the data and applied to the prediction model.The results demonstrate that the performance of the FA-IPSO-SVM model surpasses several existing methods,such as twin support vector regression and support vector machine.The model achieves hit rates of 89.59%,96.21%,and 98.74%within error ranges of±0.01%,±0.015%,and±0.02%,respectively.Finally,based on the prediction results obtained by sequentially removing input parameters,the parameters were classified into high influence(5%-7%),medium influence(2%-5%),and low influence(0-2%)categories according to their varying degrees of impact on prediction accuracy.This classi-fication provides a reference for selecting input parameters in future prediction models for endpoint carbon content. 展开更多
关键词 CONVERTER endpoint carbon content parameter classification factor analysis improved particle swarm optimization support vector machine
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Effects of Al and C content onκ-carbide precipitation and strengthening in high-Mn low-density steels:A quantitative study 被引量:1
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作者 Yu-xiang Liu Tao Xu +4 位作者 Jian-lei Zhang Feng-hui An Gang Chen Chang-jiang Song Qi-jie Zhai 《China Foundry》 2025年第4期480-492,共13页
Fe-28Mn-(10-12)Al-(0.8-1.4)C(wt.%)steels were designed to investigate the influence of varying Al and C content on precipitation behavior ofκ-carbide and its contribution to the strength of high-Mn low-density steels... Fe-28Mn-(10-12)Al-(0.8-1.4)C(wt.%)steels were designed to investigate the influence of varying Al and C content on precipitation behavior ofκ-carbide and its contribution to the strength of high-Mn low-density steels.Results reveal that both Al and C elements promoteκ-carbide precipitation,with C having a more pronounced effect.In near-rapidly solidified 10Al steel strips,increasing C content from 0.8wt.%to 1.4wt.%raises theκ-carbide size from 9.6 nm to 38.2 nm,accompanied by volume fraction increase from 10.2vol.%to 29.8vol.%.In comparison,the average size and volume fraction ofκ-carbides in 12Al0.8C steel are only 11.4 nm and 17.8vol.%,respectively.Higher Al and C content reduces the lattice mismatch between austenite andκ-carbides,thus promoting nucleation ofκ-carbides.Notably,the increase in C content results in a greater reduction in the Gibbs free energy ofκ-carbide,leading to a stronger driving force forκ-carbide formation.Consequently,as the C content increases from 0.8wt.%to 1.4wt.%,the interaction betweenκ-carbides and dislocations transforms from particle cutting to bypassing,and the maximum precipitation strengthening ofκ-carbides reaches 583 MPa.The construction of the relationship between Al and C content andκ-carbide precipitation in this study would provide valuable insights for alloy design of high-Mn steels. 展开更多
关键词 low-density steel κ-carbide Al and C content precipitation strengthening
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Effects of carbon content on the microstructure and tensile properties of a low-density steel
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作者 Yongxuan Shang Mingyu Fan +1 位作者 Shuyong Jiang Zhongwu Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第2期391-401,共11页
Carbon can change the phase components of low-density steels and influence the mechanical properties.In this study,a new method to control the carbon content and avoid the formation ofδ-ferrite by decarburization tre... Carbon can change the phase components of low-density steels and influence the mechanical properties.In this study,a new method to control the carbon content and avoid the formation ofδ-ferrite by decarburization treatment was proposed.The microstructural changes and mechanical characteristics with carbon content induced by decarburization were systematically examined.Crussard-Jaoul(C-J)analysis was employed to examine the work hardening characteristics during the tensile test.During decarburization by heat treatments,the carbon content within the austenite phase decreased,while Mn and Al were almost unchanged;this made the steel with full austenite transform into the austenite and ferrite dual phase.Meanwhile,(Ti,V)C carbides existed in both matrix phase and the mole fraction almost the same.In addition,the formation of other carbides restrained.Carbon loss induced a decrease in strength due to the weakening of the carbon solid solution.For the steel with the single austinite,the deformation mode of austenite was the dislocation planar glide,resulting in the formation of microbands.For the dual-phase steel,the deformation occurred by the dislocation planar glide of austenite first,with the increase in strain,the cross slip of ferrite took place,forming dislocation cells in ferrite.At the late stage of deformation,the work hardening of austinite increased rapidly,while that of ferrite increased slightly. 展开更多
关键词 low-density steels carbon content DECARBURIZATION strengthening mechanisms work hardening behavior
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Mechanical Properties of Railway High-strength Manufactured Sand Concrete:Typical Lithology,Stone Powder Content and Strength Grade
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作者 WANG Zhen LI Huajian +3 位作者 HUANG Fali YANG Zhiqiang WEN Jiaxin SHI Henan 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2025年第1期194-203,共10页
In order to achieve the large-scale application of manufactured sand in railway high-strength concrete structure,a series of high-strength manufactured sand concrete(HMC)are prepared by taking the manufactured sand li... In order to achieve the large-scale application of manufactured sand in railway high-strength concrete structure,a series of high-strength manufactured sand concrete(HMC)are prepared by taking the manufactured sand lithology(tuff,limestone,basalt,granite),stone powder content(0,5%,10%,15%)and concrete strength grade(C60,C80,C100)as variables.The evolution of mechanical properties of HMC and the correlation between cubic compressive strength and other mechanical properties are studied.Compared to river sand,manufactured sand enhances the cubic compressive strength,axial compressive strength and elastic modulus of concrete,while its potential microcracks weaken the flexural strength and splitting tensile strength of concrete.Stone powder content displays both positive and negative effects on mechanical properties of HMC,and the stone powder content is suggested to be less than 10%.The empirical formulas between cubic compressive strength and other mechanical properties are proposed. 展开更多
关键词 manufactured sand concrete RAILWAY mechanical property LITHOLOGY stone powder content
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Security Strategy of Digital Medical Contents Based on Blockchain in Generative AI Model
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作者 Hoon Ko Marek R.Ogiela 《Computers, Materials & Continua》 SCIE EI 2025年第1期259-278,共20页
This study presents an innovative approach to enhancing the security of visual medical data in the generative AI environment through the integration of blockchain technology.By combining the strengths of blockchain an... This study presents an innovative approach to enhancing the security of visual medical data in the generative AI environment through the integration of blockchain technology.By combining the strengths of blockchain and generative AI,the research team aimed to address the timely challenge of safeguarding visual medical content.The participating researchers conducted a comprehensive analysis,examining the vulnerabilities of medical AI services,personal information protection issues,and overall security weaknesses.This multi faceted exploration led to an indepth evaluation of the model’s performance and security.Notably,the correlation between accuracy,detection rate,and error rate was scrutinized.This analysis revealed insights into the model’s strengths and limitations,while the consideration of standard deviation shed light on the model’s stability and performance variability.The study proposed practical improvements,emphasizing the reduction of false negatives to enhance detection rate and leveraging blockchain technology to ensure visual data integrity in medical applications.Applying blockchain to generative AI-created medical content addresses key personal information protection issues.By utilizing the distributed ledger system of blockchain,the research team aimed to protect the privacy and integrity of medical data especially medical images.This approach not only enhances security but also enables transparent and tamperproof record-keeping.Additionally,the use of generative AI models ensures the creation of novel medical content without compromising personal information,further safeguarding patient privacy.In conclusion,this study showcases the potential of blockchain-based solutions in the medical field,particularly in securing sensitive medical data and protecting patient privacy.The proposed approach,combining blockchain and generative AI,offers a promising direction toward more robust and secure medical content management.Further research and advancements in this area will undoubtedly contribute to the development of robust and privacy-preserving healthcare systems,and visual diagnostic systems. 展开更多
关键词 Digitalmedical content medical diagnostic visualization security analysis generativeAI blockchain VULNERABILITY pattern recognition
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Effect of Al content on nanoprecipitates, austenite grain growth and toughness in coarse-grained heat-affected zones of Al–Ti–Ca deoxidized shipbuilding steels 被引量:1
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作者 Tingting Li Jian Yang +3 位作者 Yinhui Zhang Han Sun Yanli Chen Yuqi Zhang 《International Journal of Minerals,Metallurgy and Materials》 2025年第4期879-891,共13页
This work focuses on the influence of Al content on the precipitation of nanoprecipitates,growth of prior austenite grains(PAGs),and impact toughness in simulated coarse-grained heat-affected zones (CGHAZs) of two exp... This work focuses on the influence of Al content on the precipitation of nanoprecipitates,growth of prior austenite grains(PAGs),and impact toughness in simulated coarse-grained heat-affected zones (CGHAZs) of two experimental shipbuilding steels after being subjected to high-heat input welding at 400 kJ·cm^(-1).The base metals (BMs) of both steels contained three types of precipitates Type Ⅰ:cubic (Ti,Nb)(C,N),Type Ⅱ:precipitate with cubic (Ti,Nb)(C,N) core and Nb-rich cap,and Type Ⅲ:ellipsoidal Nb-rich precipitate.In the BM of 60Al and 160Al steels,the number densities of the precipitates were 11.37×10^(5) and 13.88×10^(5) mm^(-2),respectively The 60Al and 160Al steel contained 38.12% and 6.39% Type Ⅲ precipitates,respectively.The difference in the content of Type Ⅲ precipitates in the 60Al steel reduced the pinning effect at the elevated temperature of the CGHAZ,which facilitated the growth of PAGs The average PAG sizes in the CGHAZ of the 60Al and 160Al steels were 189.73 and 174.7μm,respectively.In the 60Al steel,the low lattice mismatch among Cu_(2)S,TiN,and γ-Al_(2)O_(3)facilitated the precipitation of Cu_(2)S and TiN onto γ-Al_(2)O_(3)during welding,which decreased the number density of independently precipitated (Ti,Nb)(C,N) particles but increased that of γ-Al_(2)O_(3)–Ti N–Cu_(2)S particles.Thus abnormally large PAGs formed in the CGHAZ of the 60Al steel,and they reached a maximum size of 1 mm.These PAGs greatly reduced the microstructural homogeneity and consequently decreased the impact toughness from 134 (0.016wt%Al) to 54 J (0.006wt%Al)at-40℃. 展开更多
关键词 oxide metallurgy Al–Ti–Ca deoxidization Al content PRECIPITATES coarse-grained heat-affected zone
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Effect of Hydrogen Content on Static and Dynamic Mechanical Behavior of Zr-Sn-Nb-Fe Alloy
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作者 Li Yuli Chen Qiuyu +3 位作者 Li Hao Sun Taotao Qu Jingwen Liu Qiong 《稀有金属材料与工程》 北大核心 2025年第8期1956-1961,共6页
Zirconium alloy cladding materials inevitably undergo hydrogen absorption in the processing and operation process of the reactor,and its static and dynamic mechanical properties are closely related to the hydrogen con... Zirconium alloy cladding materials inevitably undergo hydrogen absorption in the processing and operation process of the reactor,and its static and dynamic mechanical properties are closely related to the hydrogen content.Samples with hydrogen content ranging from 23μg/g to 132μg/g were obtained using the method of gas-phase hydrogen charging,and the influence of hydrogen content on static/dynamic mechanical properties of Zr-Sn-Nb-Fe alloy was studied.The results show that the effect of weak hydrogen charging on the ultimate tensile strength,yield strength,and elongation of zirconium alloy is not obvious.There are a large number of dimples on the fracture surface of the tensile sample before and after hydrogen charging,which is a typical ductile fracture.However,the impact toughness of Zr-Sn-Nb-Fe alloy decreases significantly after trace hydrogen charging.The impact sample without hydrogen charging shows the mixed fracture mechanism of ductile fracture and microcleavage fracture.The increase in hydrogen permeability leads to the emergence of hydride,and the deformation of high strain rate under the impact loading condition leads to secondary cracks in the microstructure.The initiation and expansion of the secondary cracks is the main reason for the reduction of the impact toughness. 展开更多
关键词 Zr-Sn-Nb-Fe hydrogen content tensile property impact property
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Influence of Si Content on the Mechanical and Tribological Properties of Laser Cladding FeCoNiBSiNb Amorphous Alloy Composite Materials
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作者 DU Xian YU Dongxin +3 位作者 LIU Jian CAI Zhihai HE Dongyu WANG Xiaolong 《材料导报》 北大核心 2025年第12期156-162,共7页
Aseries of [(Fe_(0.6)Co_(0.2)Ni_(0.2))_(0.75-0.03x)B_(0.2)Si_(0.05+0.03x)]_(96)Nb_(4) amorphous alloy composite coatings were prepared by adjusting the silicon content(x=0,1,2,3,4,5,and 6)and their microstructures and... Aseries of [(Fe_(0.6)Co_(0.2)Ni_(0.2))_(0.75-0.03x)B_(0.2)Si_(0.05+0.03x)]_(96)Nb_(4) amorphous alloy composite coatings were prepared by adjusting the silicon content(x=0,1,2,3,4,5,and 6)and their microstructures and tribological properties were investigated by laser cladding technique.Additionally,the effect of Si on the glass forming ability(GFA)of the layers was understood.Results show that an appropriate Si content can refine the microstructure of the FeCoNiBSiNb laser cladding layers and improve the mechanical and tribological properties.The hardness of the coating layer increases monotonically with the Si content.At the Si content of 4.8at%(x=0),the coating layer exhibits a relatively low hardness(734.2HV 0.1).Conversely,at the silicon content of 13.44at%(x=3),the coating layer exhibits the highest hardness(1106HV 0.1).The non-crystalline content and tensile strength exhibit an initial increase,followed by a subsequent decrease.At x=2,the coating exhibits its maximum fracture strength(2880 MPa).However,when x>2,the fracture strength of the coating decreases with an increase in x.Conversely,with an increase in Si content,the wear volume loss initially decreases and then increases.At a Si content of 10.56at%(x=2),the coating exhibits the highest non-crystalline content(42%),the highest tensile strength(2880 MPa),and the most favorable dry friction performance. 展开更多
关键词 laser cladding FeCoNiBSiNb composite layer tribological property Si content
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Study on Hydration Mechanism of Composite Cementitious Material with Large Content of Fly Ash and Slag
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作者 YANG Jinchao SHEN Chao +2 位作者 LIN Rui CAI Xinan ZUO Lian 《材料导报》 北大核心 2025年第S2期495-498,共4页
In order to adjust some properties of cement grout or concrete,some mineral admixtures are usually added in the preparation.Admixtures can reduce the cement consumption and save the cost,and also adjust the workabilit... In order to adjust some properties of cement grout or concrete,some mineral admixtures are usually added in the preparation.Admixtures can reduce the cement consumption and save the cost,and also adjust the workability of the material,improve the strength and durability of the cement stone,or reduce hydration heat of the composite cement.At present,the content of fly ash or slag is generally less than 50%among the composite cementitious materials that have been studied more,but there is little research on composite cementitious materials with large mineral admixture.In this paper,XRD,SEM,and adiabatic temperature rise tests were used to discuss hydration products and mechanism of composite cement grout with 90%content of fly ash and slag.The results show that the hydration of the composite cement grout is an alkali-activated hydration reaction,and the hydration products are mainly amorphous substances such as hydrated calcium silicate or hydrated calcium aluminate gel.The hydration reaction temperature rise is much lower than that of ordinary cement grout,and the time of the temperature peak is significantly delayed. 展开更多
关键词 large content fly ash SLAG composite cement material hydration mechanism
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Genome-wide association study(GWAS)identifies genetic loci and candidate genes for variation in protein and oil content in Sesamum indicum L.
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作者 Habtamu Kefale Rong Zhou +6 位作者 Muez Berhe Ahmed A.Abbas Chris O.Ojiewo Huan Li Ting Zhou Jun You Linhai Wang 《Oil Crop Science》 2025年第4期337-347,共11页
Sesame(Sesamum indicum L.)is an ancient diploid oilseed crop valued for its high oil content,quality protein,unsaturated fatty acids,and antioxidants.The emerging research focuses on the utilization of vegetable prote... Sesame(Sesamum indicum L.)is an ancient diploid oilseed crop valued for its high oil content,quality protein,unsaturated fatty acids,and antioxidants.The emerging research focuses on the utilization of vegetable proteins in the development of novel products and the formulation of functional foods.Developing sesame genotypes with higher protein and oil content is a current focus for improving sesame quality traits,as preferred by the sesame seed oil industry and consumers.Despite previous genome-wide association studies(GWAS)on various agronomic and biochemical traits in sesame,the genetic basis of protein content and oil content remains limited.Therefore,this study was designed to identify candidate genes and quantitative trait loci(QTLs)regulating the target traits using 401 sesame accessions grown in three environments(2018WH,2018LQ,and 2022WH).The protein and oil content in the sesame population varied significantly.The protein content ranged from 15.06%to 26.45%,while the oil content was between 41.68%and 60.15%.Furthermore,the white seeds had a higher oil content,while the black seeds had a higher protein content,indicating an association between seed colour and oil and protein content.GWAS results revealed that 632 and 269 QTLs were selected as significant genetic regions for protein and oil content,respectively.Of these significant QTLs,we identified 10 and 22 stable QTLs for protein and oil content,respectively.A total of 17 candidate genes related to protein and oil content were identified within 32 stable quantitative trait loci(QTLs).Interestingly,two variant sites,SNP13:10093594 and In Del13:10935497,related to protein content,were identified in the gene sequences of SINPZ1300586 and SINPZ1300694.Four SNPs,SNP1:22608987,SNP4:13355820,SNP8:21686488,and SNP11:142842,for oil content were found correspond to the genes SINPZ0102106,SINPZ0401222,SINPZ0801731,and SINPZ1100015,respectively.The findings provide light on the genetic basis of protein and oil characteristics.These genes and QTLs can aid the molecular breeding and genetic engineering of innovative sesame germplasm,with improved potential for protein and oil content,as well as desired quality attributes. 展开更多
关键词 SESAME Quality traits Oil content Protein content GWAS QTLS
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Loess compaction at different water contents:Effects on hydraulic conductivity,compression behavior,microstructure,and water distribution
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作者 Kangze Yuan Wankui Ni +3 位作者 Xiangfei Lü Haiman Wang Yongpeng Nie Gabriele Della Vecchia 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第8期5307-5317,共11页
In this study,compacted loess samples with varying compaction water content but identical dry density were prepared to investigate the evolution of their hydraulic conductivity and compression behavior.Additionally,en... In this study,compacted loess samples with varying compaction water content but identical dry density were prepared to investigate the evolution of their hydraulic conductivity and compression behavior.Additionally,environmental scanning electron microscopy(ESEM)and nuclear magnetic resonance(NMR)analyses were conducted to gain microstructural insights into loess behavior at the laboratory scale.The results indicate that the maximum saturated hydraulic conductivity is observed at the lowest compaction water content,particularly in the early stage of permeability tests.In particular,for loess compacted at water contents below the optimum(as determined by the modified Proctor compaction test),the hydraulic conductivity decreases throughout the permeability tests.Conversely,when the water content exceeds the optimum level,the hydraulic conductivity shows an increasing trend.In terms of compression behavior,when the as-compacted samples are loaded in oedometer conditions,an increase in material compressibility is observed with increasing compaction water content.Again,a different phenomenological behavior was observed when the compaction water content exceeded the optimum,i.e.an abrupt increase in loess compressibility.ESEM tests provide microstructural confirmation of this evidence,as the surface morphology of the compacted loess changes significantly with increasing compaction water content.The microstructural evolution was also quantified in terms of area ratio using image processing software.Finally,NMR was used to quantify the intra-and inter-aggregate water at different compaction water contents,once again highlighting a threshold for the presence or absence of inter-aggregate water similar to the optimum water content. 展开更多
关键词 Compacted loess Water content COMPRESSIBILITY Hydraulic conductivity MICROSTRUCTURE
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Carnitine content and its influencing factors in marine animals collected from China's offshore region and the Northwest Pacific Ocean
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作者 Yufeng Gao Zhengguo Cui +10 位作者 Jianwei Li Keming Qu Qingkui Wang Lanlan He Xiangtao Liu Xiner Zhao Liuyizhi Zhang Lingxiao Li Ying Bai Fangqun Dai Qingjing Hu 《Acta Oceanologica Sinica》 2025年第9期158-168,共11页
Carnitine(CAR) is a vital quaternary ammonium compound. However, the characteristics of CAR content and its influencing factors across different marine animal species remain poorly understood. This study examined the ... Carnitine(CAR) is a vital quaternary ammonium compound. However, the characteristics of CAR content and its influencing factors across different marine animal species remain poorly understood. This study examined the CAR content in 258 marine animals, representing 54 species across seven classes, collected from coastal and offshore regions of China and the Northwest Pacific Ocean(NWPO) between May 2020 and June 2022. The CAR content ranged from0.01 mmol/kg to 1.33 mmol/kg, with a mean value of(0.15 ± 0.18) mmol/kg(mean ± standard deviation). The highest CAR content was observed in Crustacea [(0.48 ± 0.38) mmol/kg], which was four times greater than the average CAR content in the other classes [(0.12 ± 0.11) mmol/kg]. Overall, the CAR content exhibited minor variation among marine animals, potentially because the carnitine pool maintains its dynamic balance. Additionally, significant correlations were observed between the CAR content and environmental factors in some species: a negative correlation with seawater temperature and positive correlations with latitude, seawater salinity, and depth. These results suggest that the CAR content in marine animals is influenced by environmental changes. This study provides theoretical insights for understanding the characteristics and influencing factors of CAR content in marine animals. 展开更多
关键词 CARNITINE marine animal content characteristic influencing factor
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