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Unraveling the significance of cobalt on transformation kinetics,crystallography and impact toughness in high-strength steels
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作者 Yishuang Yu Jingxiao Zhao +3 位作者 Xuelin Wang Hui Guo Zhenjia Xie Chengjia Shang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第2期380-390,共11页
This work reveals the significant effects of cobalt(Co)on the microstructure and impact toughness of as-quenched highstrength steels by experimental characterizations and thermo-kinetic analyses.The results show that ... This work reveals the significant effects of cobalt(Co)on the microstructure and impact toughness of as-quenched highstrength steels by experimental characterizations and thermo-kinetic analyses.The results show that the Co-bearing steel exhibits finer blocks and a lower ductile-brittle transition temperature than the steel without Co.Moreover,the Co-bearing steel reveals higher transformation rates at the intermediate stage with bainite volume fraction ranging from around 0.1 to 0.6.The improved impact toughness of the Co-bearing steel results from the higher dense block boundaries dominated by the V1/V2 variant pair.Furthermore,the addition of Co induces a larger transformation driving force and a lower bainite start temperature(BS),thereby contributing to the refinement of blocks and the increase of the V1/V2 variant pair.These findings would be instructive for the composition,microstructure design,and property optimization of high-strength steels. 展开更多
关键词 high-strength steel COBALT transformation kinetics CRYSTALLOGRAPHY impact toughness
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Soliton Solutions of a Coupled KdV System via Backlund Transformation
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作者 CAO Xifang WU Yiheng +2 位作者 LU Yi XU Wenjing XIA Yutong 《应用数学》 北大核心 2025年第1期211-216,共6页
In this paper we use Böcklund transformation to construct soliton solutions for a coupled KdV system.This system was first proposed by Wang in 2010.First we generalize the well-known Bäcklund transformation ... In this paper we use Böcklund transformation to construct soliton solutions for a coupled KdV system.This system was first proposed by Wang in 2010.First we generalize the well-known Bäcklund transformation for the KdV equation to such coupled KdV system.Then from a trivial seed solution,we construct soliton solutions.We also give a nonlinear superposition formula,which allows us to generate multi-soliton solutions. 展开更多
关键词 KdV equation Coupled KdV system B¨acklund transformation SOLITON
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Stage IV malignant transformation of mature cystic teratoma palliatively treated with concurrent chemoradiotherapy:A case report
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作者 Saori Kondo Takashi Suzuki +4 位作者 Kanato Yoshiike Sakura Yamanaka Kenta Sonehara Hiroshi Nabeshima Osamu Oguchi 《World Journal of Clinical Cases》 SCIE 2025年第1期56-61,共6页
BACKGROUND Malignant transformation(MT)of mature cystic teratoma(MCT)has a poor prognosis,especially in advanced cases.Concurrent chemoradiotherapy(CCRT)has an inhibitory effect on MT.CASE SUMMARY Herein,we present a ... BACKGROUND Malignant transformation(MT)of mature cystic teratoma(MCT)has a poor prognosis,especially in advanced cases.Concurrent chemoradiotherapy(CCRT)has an inhibitory effect on MT.CASE SUMMARY Herein,we present a case in which CCRT had a reduction effect preoperatively.A 73-year-old woman with pyelonephritis was referred to our hospital.Computed tomography revealed right hydronephrosis and a 6-cm pelvic mass.Endoscopic ultrasound-guided fine-needle biopsy(EUS-FNB)revealed squamous cell carci-noma.The patient was diagnosed with MT of MCT.Due to her poor general con-dition and renal malfunction,we selected CCRT,expecting fewer adverse effects.After CCRT,her performance status improved,and the tumor size was reduced;surgery was performed.Five months postoperatively,the patient developed dis-semination and lymph node metastases.Palliative chemotherapy was ineffective.She died 18 months after treatment initiation.CONCLUSION EUS-FNB was useful in the diagnosis of MT of MCT;CCRT suppressed the disea-se and improved quality of life. 展开更多
关键词 Mature cystic teratoma Malignant transformation Squamous cell carcinoma Concurrent chemoradiotherapy Endoscopic ultrasound-guided fine-needle biopsy Case report
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Xiamen after 20 Years of Ecological Transformation
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作者 ZACHARY G.LUNDQUIST 《China Today》 2025年第1期66-68,共3页
The efforts Xiamen has made in ecological protection over the last 20 years have helped it become a beautiful and clean city.TWENTY years ago,I had the opportunity to travel to the city of Xiamen in southeastern China... The efforts Xiamen has made in ecological protection over the last 20 years have helped it become a beautiful and clean city.TWENTY years ago,I had the opportunity to travel to the city of Xiamen in southeastern China’s Fujian Province.Unfortunately,due to the fact that I was in a rush,I did not have the chance to see the whole city.My memory of Xiamen was its pleasant climate and unforgettable beauty-I knew if I ever got the opportunity,I would revisit this place.Twenty years went by until I was able to return to this city again.After emerging from the airport,I realized that I had grown older,while Xiamen was becoming increasingly youthful and vibrant.What exactly had given this city such vitality? 展开更多
关键词 ECOLOGICAL XIAMEN transformation
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Development of an Agrobacterium tumefaciens-mediated transformation system for somatic embryos and transcriptome analysis of LcMYB1's inhibitory effect on somatic embryogenesis in Litchi chinensis
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作者 Yaqi Qin Bo Zhang +6 位作者 Xueliang Luo Shiqian Wang Jiaxin Fu Zhike Zhang Yonghua Qin Jietang Zhao Guibing Hu 《Journal of Integrative Agriculture》 2025年第2期594-609,共16页
Litchi has great economic significance as a global fruit crop.However,the advancement of litchi functional genomics has encountered substantial obstacles due to its recalcitrance to stable transformation.Here,we prese... Litchi has great economic significance as a global fruit crop.However,the advancement of litchi functional genomics has encountered substantial obstacles due to its recalcitrance to stable transformation.Here,we present an efficacious Agrobacterium tumefaciens-mediated transformation system in somatic embryos of‘Heiye'litchi.This system was developed through the optimization of key variables encompassing explant selection,A.tumefaciens strain delineation,bacterium concentration,infection duration,and infection methodology.The subsequent validation of the transformation technique in litchi was realized through the ectopic expression of LcMYB1,resulting in the generation of transgenic calli.However,the differentiation of transgenic calli into somatic embryos encountered substantial challenges.To delineate the intricate molecular underpinnings of LcMYB1's inhibitory role in somatic embryo induction,a comprehensive transcriptome analysis was conducted that encompassed embryogenic calli(C),globular embryos(G),and transgenic calli(TC).A total of 1,166 common differentially expressed genes(DEGs)were identified between C-vs.-G and C-vs.-TC.Gene Ontology(GO)annotation and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway analysis revealed that these common DEGs were mostly related to plant hormone signal transduction pathways.Furthermore,RT-qPCR corroborated the pronounced down-regulation of numerous genes that are associated with somatic embryo induction within the transgenic calli.The development of this transformation system provides valuable support for functional genomics research in litchi. 展开更多
关键词 Litchi chinensis A.tumefaciens transformation LcMYB1 somatic embryo
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Digitalization Empowers Higher Education Teaching Management-Reform and Innovation,Shaping and Transformation,Role and Inspiration,Challenges and Countermeasures
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作者 Ce Zhang Peng Liu +2 位作者 Xiaoying Liu Meng Wei Xuejie Zhao 《计算机教育》 2025年第3期10-23,共14页
The combination and application of information technology and higher education have led to changes in the form and mode of teaching management in higher education,promoting the continuous deepening of digital transfor... The combination and application of information technology and higher education have led to changes in the form and mode of teaching management in higher education,promoting the continuous deepening of digital transformation in higher education.This paper discusses higher education management innovation triggered by digital technology and the new appearance of digital university governance,digital evaluation management,and internal governance of higher education.From the perspective of forging new forms,models,and paths of digital management through digital technology,this paper focuses on analyzing the reshaping of management systems by digitalization in higher education.The promotion and inspiration of digitalization on management system reform are provided,including typical features brought about,new paths opened up,and new advantages shaped.It is emphasized that the establishment of digital management system needs to rely on the systematic integration of multiple aspects.Finally,the challenges and solutions faced by the digital management system are deeply analyzed from the aspects of collaborative management and services,management process interoperability,evaluation and trust protection,and personnel digital literacy.Digital technology drives the transformation of higher education management system,resulting in new forms,models,paths,and methods of networked and digital management based on intelligent analysis and processing of educational and teaching data and promoting higher education management toward digital governance.The comprehensive establishment of a digital management system will unleash strong potential for universities to better fulfill their functions,and the high-quality development of higher education will be more solid and powerful. 展开更多
关键词 Higher education Digital transformation Management system Digital management
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Streamlined Agrobacterium rhizogenes-mediated hairy root transformation for efficient CRISPR/Cas9-based gene editing evaluation in diverse Citrullus cultivars
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作者 Yong Zhao Hongju Zhu +7 位作者 Xuqiang Lu Muhammad Anees Nan He Dongdong Yang Zihao Chen Zonglie Hong Junhong Zhang Wenge Liu 《Horticultural Plant Journal》 2025年第2期816-826,共11页
The CRISPR/Cas9 genome-editing system serves as a pivotal tool for enhancing crop genetics.Within this system,single guide RNAs(sgRNAs)are instrumental in the precise cleavage of DNA double strands.However,the efficie... The CRISPR/Cas9 genome-editing system serves as a pivotal tool for enhancing crop genetics.Within this system,single guide RNAs(sgRNAs)are instrumental in the precise cleavage of DNA double strands.However,the efficiency of gene editing varies among sgRNAs,emphasizing the need to meticulously select target sites,especially in the context of Citrullus lanatus,a species notorious for its challenging and inefficient generation of transgenic plants through stable transformation.This study employed an Agrobacterium rhizogenes-mediated hairy root method to assess effective target sites for gene editing of ClCIPK17 across various Citrullus species.Hairy roots were successfully induced in different plant tissues at diverse growth stages of Citrullus lanatus,Citrullus mucosospermus,and Citrullus amarus.Employing a vector with two sgRNAs(sgRNA1 and sgRNA5)positioned within conserved regions of exon 1 and exon 5 of ClCIPK17 in the CRISPR/Cas9 system,targeted mutations were detected in 90.9%of accessions across the four Citrullus species.Notably,73.94%of all examined hairy roots exhibited mutations at the sgRNA1 site,while the sgRNA5 site showed no mutations.Among the 31 different mutation types identified at the sgRNA1 site,base deletion was the most prevalent.Using the sgRNA1 site of ClCIPK17,stable transgenic watermelon buds were obtained from explants,and the targeted mutations of the sgRNA1 site were confirmed.These findings underscore the viability of the hairy root transformation system in assessing the editing efficiency of sgRNA targets in diverse Citrullus species. 展开更多
关键词 Citrullus lanatus sgRNAs Agrobacterium rhizogenes Hairy root transformation CRISPR/Cas9
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National standard proposals on digital transformation approved
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《China Standardization》 2025年第1期8-8,共1页
The digital economy has become an important impetus of global economic growth. The rapid development of emerging and key technological fields, such as the new generation of information technology and biotechnology, ha... The digital economy has become an important impetus of global economic growth. The rapid development of emerging and key technological fields, such as the new generation of information technology and biotechnology, has put forward new requirements for standards development.However, the traditional mode of standards development relying on paper documents faces problems such as low efficiency, long cycle, and relatively low quality, which fails to meet current demands. 展开更多
关键词 transformation approved TECHNOLOGICAL
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The Road of“Coal to Gas”in the Transformation of Energy Structure—Current Status and Strategic Suggestions for Foshan City’s Policy Implementation
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作者 Wanyi Chen Yifeng Huang 《Journal of Electronic Research and Application》 2025年第1期74-80,共7页
Under the guidance of national policies,the“coal to gas”project has become one of the important measures to promote the transformation of energy structure in China.Foshan,an important industrial town in Guangdong pr... Under the guidance of national policies,the“coal to gas”project has become one of the important measures to promote the transformation of energy structure in China.Foshan,an important industrial town in Guangdong province,the implementation of the“coal to gas”policy has demonstrated significance for the optimization of the national energy structure.Through the analysis of the change in Foshan’s energy consumption structure and the implementation of the policy,this paper found that there were some challenges in the policy implementation process,such as high economic cost,lagging infrastructure,low social acceptance,and lack of technical personnel.To address this,suggestions are put forward,including increasing financial subsidies,improving laws and regulations,promoting technological innovation,and encouraging social inclusion policies.These recommendations aim to provide guidance and reference for the remaining“coal to gas”projects and the development of clean energy. 展开更多
关键词 Coal to gas Energy structure transformation Foshan City Clean energy
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Evidence-Based Practice of Nutrition Management in Chronic Heart Failure Patients Based on Knowledge-to-Action Transformation Model
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作者 Jing Zhang Junjun Liu 《Open Journal of Applied Sciences》 2025年第2期400-410,共11页
Objective: To develop a best-evidence-based optimal nutrition management plan for patients with chronic heart failure, apply it in clinical practice, and evaluate its effectiveness. Methods: Use the KTA knowledge tran... Objective: To develop a best-evidence-based optimal nutrition management plan for patients with chronic heart failure, apply it in clinical practice, and evaluate its effectiveness. Methods: Use the KTA knowledge translation model to guide evidence-based practice in nutrition management, and compare the nutritional status, cardiac function status, quality of life, and quality review indicators of chronic heart failure patients before and after the application of evidence. Results: After the application of evidence, the nutritional status indicators (MNA-SF score, albumin, hemoglobin) of two groups of heart failure patients significantly increased compared to before the application of evidence, with statistically significant differences (p Conclusion: The KTA knowledge translation model provides methodological guidance for the implementation of evidence-based practice for heart failure patients. This evidence-based practice project is beneficial for improving the outcomes of malnutrition in chronic heart failure patients and is conducive to standardizing nursing pathways, thereby promoting the improvement of nursing quality. 展开更多
关键词 Chronic Heart Failure Knowledge transformation Mode Nutrition Management Evidence-Based Practice
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N-Fold Darboux Transformation and Various Solutions for the Coupled mKdV Equations
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作者 Chunmei Fang 《Journal of Applied Mathematics and Physics》 2025年第2期381-391,共11页
In this paper, we get the N-fold Darboux transformation with multi-parameters for the coupled mKdV equations with the help of a guage transformation of the spectral problem. As an application, some new multi-soliton s... In this paper, we get the N-fold Darboux transformation with multi-parameters for the coupled mKdV equations with the help of a guage transformation of the spectral problem. As an application, some new multi-soliton solutions and complexiton solutions are obtained from choosing the appropriate seed solution. All obtained solutions and N-fold Darboux transformations are expressed using the Vandermonde-like determinants. 展开更多
关键词 The N-fold Darboux transformation The Coupled mKdV Equations Multi-Soliton Solutions Complexiton Solutions
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Construction of Vocational Education Quality Evaluation Index System from the Perspective of Digital Transformation Based on the Analytic Hierarchy Process of Higher Vocational Colleges in Hainan Province,China
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作者 Limei Fu 《Journal of Contemporary Educational Research》 2025年第1期282-289,共8页
In the context of the digital transformation of vocational education,a quality evaluation index system has been constructed.Based on a questionnaire survey conducted among higher vocational colleges and enterprises in... In the context of the digital transformation of vocational education,a quality evaluation index system has been constructed.Based on a questionnaire survey conducted among higher vocational colleges and enterprises in Hainan Province,it has been found that the quality of vocational education generally depends on the talent training program and professional construction at the macro level.At the meso level,the teacher level and teaching environment are critical,while at the micro level,the evaluation of talent training quality cannot be underestimated.Strategies for quality improvement in vocational education are proposed from the perspectives of talent training programs,major construction,teacher development,teaching environment,and talent training quality,all under the lens of digital transformation. 展开更多
关键词 Digital transformation Vocational education Evaluation index system
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A Study on the Digital Transformation of Higher Education in Egypt
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作者 Gang Hu Ruonan Cao 《Journal of Contemporary Educational Research》 2025年第2期101-105,共5页
With the advancement of information technology,the digital transformation of higher education has become a global trend in educational reform.Egypt has propelled the modernization of its higher education system throug... With the advancement of information technology,the digital transformation of higher education has become a global trend in educational reform.Egypt has propelled the modernization of its higher education system through digital means,focusing on enhancing teachers’digital teaching capabilities,improving course quality,and establishing a policy environment that supports digital instruction.The driving forces behind Egypt’s transformation include meeting the demand for skilled talent due to economic reforms,participating in internationalization processes,and the impetus provided by public diplomacy.By introducing high-quality international resources,deepening scientific research collaboration,and applying digital technologies,Egypt has effectively alleviated issues of resource insufficiency and uneven development,thereby enhancing its capacity for higher education quality assurance.Egypt’s practice demonstrates that digitalization is a key pathway for developing countries to improve the quality of higher education,providing valuable insights for constructing sustainable models of higher education development. 展开更多
关键词 Higher education Public diplomacy Digital transformation
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ESG rating and transformation upgrading of enterprises:An empirical test based on the heterogeneity of listed A-share enterprises
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作者 WEI Yu-xin LI Peng-yu +1 位作者 LI Yan CHEN Xi-meng 《Ecological Economy》 2025年第1期48-65,共18页
ESG(Environmental,Social,and Governance)performance has emerged as a central metric in assessing corporate sustainability.Utilizing ESG rating data for A-share listed companies on the Shanghai Stock Exchange spanning ... ESG(Environmental,Social,and Governance)performance has emerged as a central metric in assessing corporate sustainability.Utilizing ESG rating data for A-share listed companies on the Shanghai Stock Exchange spanning from 2019 to 2022,coupled with measures of corporate transformation and upgrading,this study introduces green innovation as a mediating variable to dissect the impact of ESG ratings on corporate transformation and upgrading.The key findings of this research are as follows:(1)ESG ratings positively influence corporate transformation and upgrading,a conclusion that retains robustness after a comprehensive series of tests and discussions on endogeneity.(2)Mechanism analysis reveals that ESG ratings foster corporate transformation and upgrading by enhancing corporate green innovation.(3)In comparison with other industries,the influence of ESG ratings on corporate transformation and upgrading is notably more pronounced among heavily polluting industries among listed companies in China.Additionally,ESG ratings exhibit a more significant promotional effect on non-state-owned enterprises compared to state-owned enterprises.Larger enterprises play a more substantial role in transformation and upgrading than small and medium-sized enterprises.The promotional effect of ESG ratings is more evident in enterprises with poor information disclosure quality.Furthermore,as media attention increases,so does the impact of ESG ratings on corporate transformation.This study offers valuable policy insights from the ESG rating perspective,aiming to propel corporate transformation and upgrading,thereby contributing to economic high-quality and sustainable development. 展开更多
关键词 ESG rating enterprise transformation and upgrading heterogeneity analysis
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In an Ocean or a River:Bilinear Auto-Backlund Transformations and Similarity Reductions on an Extended Time-Dependent(3+1)-Dimensional Shallow Water Wave Equation
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作者 GAO Xin-yi 《China Ocean Engineering》 2025年第1期160-165,共6页
With respect to oceanic fluid dynamics,certain models have appeared,e.g.,an extended time-dependent(3+1)-dimensional shallow water wave equation in an ocean or a river,which we investigate in this paper.Using symbolic... With respect to oceanic fluid dynamics,certain models have appeared,e.g.,an extended time-dependent(3+1)-dimensional shallow water wave equation in an ocean or a river,which we investigate in this paper.Using symbolic computation,we find out,on one hand,a set of bilinear auto-Backlund transformations,which could connect certain solutions of that equation with other solutions of that equation itself,and on the other hand,a set of similarity reductions,which could go from that equation to a known ordinary differential equation.The results in this paper depend on all the oceanic variable coefficients in that equation. 展开更多
关键词 OCEAN RIVER extended time-dependent(3+1)-dimensional shallow water wave equation bilinear auto-Bäcklund transformation similarity reduction symbolic computation
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Green transformation paths of resource-based cities in China from the configuration perspective
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作者 GONG Qunxi 《Regional Sustainability》 2024年第3期40-53,共14页
Green transformation is an unavoidable choice for resource-based cities(RBCs)that face resource depletion and environmental pollution.Existing research has focused primarily on specific RBCs,making it challenging to a... Green transformation is an unavoidable choice for resource-based cities(RBCs)that face resource depletion and environmental pollution.Existing research has focused primarily on specific RBCs,making it challenging to apply green transformation strategies universally across cities.The fuzzy set qualitative comparative analysis(fsQCA)is a combination of qualitative and quantitative analyses that can handle multiple concurrent causality problems and determine how different conditions combine into configurations and generate an outcome.Thus,to address this gap,in this study,we established a research framework for green transformation and utilized the fsQCA to examine the configurations of 113 RBCs in China.By incorporating the element of time,this study explored the dynamic evolution of solutions in 2013,2016,and 2019.The main findings indicate that individual elements do not constitute the necessary conditions for improving the green transformation efficiency(GTE),and the systematic combination of multiple conditions is an effective path for realizing the improvement of the GTE in RBCs.Green transformation paths of RBCs exhibit the same destination through different paths.Additionally,the combination of system environment elements and system structure elements is both complementary and alternative.Differences in RBCs have led to various factor combinations and development paths,but there are some similarities in the key elements of the factor combinations at different stages.Economic environment,government support,and technological innovation are key factors that universally enhance the GTE in RBCs.These insights can assist city managers in formulating policies to drive green transformation and contribute to a better theoretical understanding of green transformation paths in RBCs. 展开更多
关键词 Green transformation path Green transformation efficiency Resource-based cities Configuration analysis Fuzzy set qualitative comparative analysis(fsQCA)
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Influence of cooling rate on phase transformation and microstructure of Ti-50.9%Ni shape memory alloy 被引量:4
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作者 张艳秋 江树勇 +1 位作者 赵亚楠 唐明 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第11期2685-2690,共6页
Heat treatment of Ti-50.9%Ni (mole fraction) alloy was studied by differential scanning calorimetry, X-ray diffraction, scanning electron microscopey and energy dispersive X-ray analysis to investigate the influence... Heat treatment of Ti-50.9%Ni (mole fraction) alloy was studied by differential scanning calorimetry, X-ray diffraction, scanning electron microscopey and energy dispersive X-ray analysis to investigate the influence of cooling rate on transformation behavior and microstructures of NiTi shape memory alloy. The experimental results show that three-stage phase transformation can be induced at a very low cooling rate such as cooling in furnace. The cooling rate also has a great influence on the phase transformation temperatures. Both martensitic start transformation temperature (Ms) and martensitic finish transformation temperature (Mf) decrease with the decrease of the cooling rate, and decreasing the cooling rate contributes to enhancing the M→A austenite transformation temperature. The phase transformation hysteresis (Af-Mf) increases with the decrease of the cooling rate. Heat treatment is unable to eliminate the textures formed in hot working of NiTi sample, but can weaken the intensity of them. The cooling rate has little influence on the grain size. 展开更多
关键词 NiTi alloy shape memory alloy phase transformation cooling rate martensitic transformation temperature austenite transformation temperature
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Hemorrhagic transformation in patients with large-artery atherosclerotic stroke is associated with the gut microbiota and lipopolysaccharide 被引量:1
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作者 Qin Huang Minping Wei +3 位作者 Xianjing Feng Yunfang Luo Yunhai Liu Jian Xia 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第7期1532-1540,共9页
Hemorrhagic transformation is a major complication of large-artery atheroscle rotic stroke(a major ischemic stro ke subtype)that wo rsens outcomes and increases mortality.Disruption of the gut microbiota is an importa... Hemorrhagic transformation is a major complication of large-artery atheroscle rotic stroke(a major ischemic stro ke subtype)that wo rsens outcomes and increases mortality.Disruption of the gut microbiota is an important feature of stroke,and some specific bacteria and bacterial metabolites may contribute to hemorrhagic transformation pathogenesis.We aimed to investigate the relationship between the gut microbiota and hemorrhagic transformation in largearte ry atheroscle rotic stro ke.An observational retrospective study was conducted.From May 2020 to September 2021,blood and fecal samples were obtained upon admission from 32 patients with first-ever acute ischemic stroke and not undergoing intravenous thrombolysis or endovascular thrombectomy,as well as 16 healthy controls.Patients with stro ke who developed hemorrhagic transfo rmation(n=15)were compared to those who did not develop hemorrhagic transformation(n=17)and with healthy controls.The gut microbiota was assessed through 16S ribosomal ribonucleic acid sequencing.We also examined key components of the lipopolysaccharide pathway:lipopolysaccharide,lipopolysaccharide-binding protein,and soluble CD14.We observed that bacterial diversity was decreased in both the hemorrhagic transformation and non-hemorrhagic transfo rmation group compared with the healthy controls.The patients with ischemic stro ke who developed hemorrhagic transfo rmation exhibited altered gut micro biota composition,in particular an increase in the relative abundance and dive rsity of members belonging to the Enterobacteriaceae family.Plasma lipopolysaccharide and lipopolysaccharide-binding protein levels were higher in the hemorrhagic transformation group compared with the non-hemorrhagic transfo rmation group.lipopolysaccharide,lipopolysaccharide-binding protein,and soluble CD14 concentrations were associated with increased abundance of Enterobacte riaceae.Next,the role of the gut microbiota in hemorrhagic transformation was evaluated using an experimental stroke rat model.In this model,transplantation of the gut microbiota from hemorrhagic transformation rats into the recipient rats triggered higher plasma levels of lipopolysaccharide,lipopolysaccharide-binding protein,and soluble CD14.Ta ken togethe r,our findings demonstrate a noticeable change in the gut microbiota and lipopolysaccharide-related inflammatory response in stroke patients with hemorrhagic transformation.This suggests that maintaining a balanced gut microbiota may be an important factor in preventing hemorrhagic transfo rmation after stro ke. 展开更多
关键词 gut microbiota hemorrhagic transformation INFLAMMATION LIPOPOLYSACCHARIDE STROKE
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Formation and transformation of metastable LPSO building blocks clusters in Mg-Gd-Y-Zn-Zr alloys by spinodal decomposition and heterogeneous nucleation 被引量:1
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作者 Xin Zhao Zhong Yang +2 位作者 Jiachen Zhang Minxian Liang Liying Wang 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第2期673-686,共14页
To study the formation and transformation mechanism of long-period stacked ordered(LPSO)structures,a systematic atomic scale analysis was conducted for the structural evolution of long-period stacked ordered(LPSO)stru... To study the formation and transformation mechanism of long-period stacked ordered(LPSO)structures,a systematic atomic scale analysis was conducted for the structural evolution of long-period stacked ordered(LPSO)structures in the Mg-Gd-Y-Zn-Zr alloy annealed at 300℃~500℃.Various types of metastable LPSO building block clusters were found to exist in alloy structures at different temperatures,which precipitate during the solidification and homogenization process.The stability of Zn/Y clusters is explained by the first principles of density functional theory.The LPSO structure is distinguished by the arrangement of its different Zn/Y enriched LPSO structural units,which comprises local fcc stacking sequences upon a tightly packed plane.The presence of solute atoms causes local lattice distortion,thereby enabling the rearrangement of Mg atoms in the different configurations in the local lattice,and local HCP-FCC transitions occur between Mg and Zn atoms occupying the nearest neighbor positions.This finding indicates that LPSO structures can generate necessary Schockley partial dislocations on specific slip surfaces,providing direct evidence of the transition from 18R to 14H.Growth of the LPSO,devoid of any defects and non-coherent interfaces,was observed separately from other precipitated phases.As a result,the precipitation sequence of LPSO in the solidification stage was as follows:Zn/Ycluster+Mg layers→various metastable LPSO building block clusters→18R/24R LPSO;whereas the precipitation sequence of LPSO during homogenization treatment was observed to be as follows:18R LPSO→various metastable LPSO building block clusters→14H LPSO.Of these,14H LPSO was found to be the most thermodynamically stable structure. 展开更多
关键词 LPSO Spinodal decomposition Homogenization treatment CLUSTERS Phase transformation
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Precise regulation of the phase transformation for pyrolusite during the reduction roasting process 被引量:1
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作者 Ruofeng Wang Peng Gao +3 位作者 Shuai Yuan Yanjun Li Yingzhi Liu Cheng Huang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CSCD 2024年第1期81-90,共10页
The mechanism involved in the phase transformation process of pyrolusite (MnO_(2)) during roasting in a reducing atmosphere was systematically elucidated in this study,with the aim of effectively using low-grade compl... The mechanism involved in the phase transformation process of pyrolusite (MnO_(2)) during roasting in a reducing atmosphere was systematically elucidated in this study,with the aim of effectively using low-grade complex manganese ore resources.According to single-factor experiment results,the roasted product with a divalent manganese (Mn^(2+)) distribution rate of 95.30% was obtained at a roasting time of 25 min,a roasting temperature of 700℃,a CO concentration of 20at%,and a total gas volume of 500 mL·min^(-1),in which the manganese was mainly in the form of manganosite (MnO).Scanning electron microscopy and Brunauer–Emmett–Teller theory demonstrated the microstructural evolution of the roasted product and the gradual reduction in the pyrolusite ore from the surface to the core Thermodynamic calculations,X-ray photoelectron spectroscopy,and X-ray diffractometry analyses determined that the phase transformation of pyrolusite followed the order of MnO_(2)→Mn_(2)O_(3)→Mn_(3)O_(4)→MnO phase by phase,and the reduction of manganese oxides in each valence state proceeded simultaneously. 展开更多
关键词 PYROLUSITE phase transformation reduction roasting microstructural evolution reaction mechanism
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