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Sludge Management: Integrating the Principle of Circular Economy into the Concept of Sustainability
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作者 Ludovico Spinosa 《Journal of Environmental Science and Engineering(A)》 CAS 2025年第1期53-59,共7页
The development of sustainable sludge management systems requires looking at them with a new vision in which the concepts of SD(Sustainable Development)must integrate those of CE(Circular Economy),both concepts subjec... The development of sustainable sludge management systems requires looking at them with a new vision in which the concepts of SD(Sustainable Development)must integrate those of CE(Circular Economy),both concepts subject to the principles of TD(Thermodynamics),thus allowing the adoption of actions that are all the more effective the more complete the evaluation of the social dimension has been.This involves a new“Way of thinking”which sees the sludge system as the“Locomotive”of the entire wastewater/sludge treatment train and is developed through“Ways of acting”which includes both“Technical”actions to maximize recoveries of useful materials and/or or energy,and“Socio/Institutional”actions to overcome barriers linked to local cultures and traditions,also considering that the specific local context heavily influences the choices capable of satisfying the concepts of CE.It follows the need of issuing realistic and applicable regulations and overcoming social barriers,such as lack of infrastructure and/or qualified personnel,to achieve an effective integration of the concepts of CE with the more general ones of sustainability. 展开更多
关键词 circular economy REGULATION sludge management STANDARDIZATION sustainability.
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Optimizing circular rotations in confined systems via enhanced self-driven speed of active nematics
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作者 Tian Tang Chun-lai Ren Yu-qiang Ma 《Communications in Theoretical Physics》 2025年第3期157-164,共8页
Active matter exhibits collective motions at various scales.Geometric confinement has been identified as an effective way to control and manipulate active fluids,with much attention given to external factors.However,t... Active matter exhibits collective motions at various scales.Geometric confinement has been identified as an effective way to control and manipulate active fluids,with much attention given to external factors.However,the impact of the inherent properties of active particles on collective motion under confined conditions remains elusive.Here,we use a highly tunable active nematics model to study active systems under confinement,focusing on the effect of the self-driven speed of active particles.We identify three distinct states characterized by unique particle and flow fields within confined active nematic systems,among which circular rotation emerges as a collective motion involving rotational movement in both particle and flow fields.The theoretical phase diagram shows that increasing the self-driven speed of active particles significantly enhances the region of the circular rotation state and improves its stability.Our results provide insights into the formation of high quality vortices in confined active nematic systems. 展开更多
关键词 active nematics collective motion CONFINEMENT circular rotation
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Circular RNAs inducing the osteogenic differentiation of dental mesenchymal stem cells via microRNA sponging
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作者 Yong-Song Jiang Wei-Sheng Wei +1 位作者 Dao-Tao Xie Gang Guo 《World Journal of Stem Cells》 2025年第5期12-25,共14页
Circular RNAs(circRNAs)are a distinct type of nonlinear and noncoding RNAs endogenously expressed by pre-mRNA back-splicing and crucial in transcriptional and posttranscriptional regulation.CircRNAs can regulate cellu... Circular RNAs(circRNAs)are a distinct type of nonlinear and noncoding RNAs endogenously expressed by pre-mRNA back-splicing and crucial in transcriptional and posttranscriptional regulation.CircRNAs can regulate cellular and molecular pathways through various mechanisms,such as microRNA sponging.Numerous studies have indicated the regulatory roles of circRNAs in the osteogenic differentiation of stem cells(SCs)isolated from different sources.Dental tissue-derived mesenchymal SCs(MSCs)have received considerable attention in artificial bone engineering,in which SCs are used to manufacture functional bone tissues to repair bone defects.Recently,studies have reported the regulatory roles of circRNAs in the osteogenic differentiation of dental-derived MSCs,such as apical papillae,dental pulp,and dental follicle SCs.This review aimed to discuss the findings of studies evaluating the contribution of circRNAs to the osteogenic differentiation of dental-derived MSCs. 展开更多
关键词 circular RNA Dentistry MICRORNA OSTEOGENESIS Dental stem cells
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Analysis of circularity metrology of small cylindrical workpiece with a segmenting scan method
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作者 Qiaolin Li Chuang Zeng +2 位作者 Jiali Zhao Dan Wu Liang Zhang 《Nanotechnology and Precision Engineering》 2025年第2期42-50,共9页
Owing to eccentricity and inclination, circularity of a cylindrical workpiece cannot be measured precisely by a circularity measuring machine when the workpiece has a small dimension(diameter ≤ 3 mm). In this paper, ... Owing to eccentricity and inclination, circularity of a cylindrical workpiece cannot be measured precisely by a circularity measuring machine when the workpiece has a small dimension(diameter ≤ 3 mm). In this paper, with the aim of solving this problem, circularity metrology of a small cylindrical workpiece using a segmenting scanning method is analyzed. The cross-sectional circle of the cylinder is segmented into several equivalent arcs for measurement by a two-dimensional coordinate measuring machine(profilometer). The circularity contour is obtained by stitching together arc contours obtained by data processing of the coordinates. Different segmenting patterns for coordinate scanning are considered. Measurement results are presented for three segmentation patterns, with 8, 10, and 12 equal segments, respectively.These results are evaluated in terms of the matching coefficient between neighboring arc contours on circumferential stitching, the Euclidean distance between neighboring arc contours on radial stitching, and the curvature of the arcs. From these evaluations, it is found that as the number of segments is increased, the matching coefficient increases from 0.14 to 0.50, the Euclidean distance decreases from 32 nm to 26 nm,and the curvature becomes close to the standard value. 展开更多
关键词 circularITY Precision metrology Small cylindrical part Coordinate modeling-segmenting Arc contour
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Profiling and bioinformatics analyses of circular RNAs in myocardial ischemia/reperfusion injury model in mice
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作者 Jiao-Ni Wang Ying-Ying Zhou +1 位作者 Yong-Wei Yu Jun Chen 《World Journal of Cardiology》 2025年第1期65-77,共13页
BACKGROUND Myocardial ischemia/reperfusion(I/R)injury,which is associated with high morbidity and mortality,is a main cause of unexpected myocardial injury after acute myocardial infarction.However,the underlying mech... BACKGROUND Myocardial ischemia/reperfusion(I/R)injury,which is associated with high morbidity and mortality,is a main cause of unexpected myocardial injury after acute myocardial infarction.However,the underlying mechanism remains unclear.Circular RNAs(circRNAs),which are formed from protein-coding genes,can sequester microRNAs or proteins,modulate transcription and interfere with splicing.Authoritative studies suggest that circRNAs may play an important role in myocardial I/R injury.AIM To explore the role and mechanism of circRNAs in myocardial I/R injury.METHODS We constructed a myocardial I/R injury model using ligation of the left anterior descending coronary artery,and evaluated the success of the validated model using triphenyltetrazolium chloride and hematoxylin-eosin staining.Then,left ventricular samples from different groups were selected for mRNA-sequence,and differential gene screening was performed on the obtained results.The differentially obtained mRNAs were divided into up-regulated and down-regulated according to their expression levels,and Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)functional enrichment analysis were performed,respectively.Then,the obtained circRNA and microRNA(miRNA)were paired for analysis,and the binding sites of miRNA and mRNA were virtual screened.Finally,the obtained circRNA,miRNA and mRNA were constructed by ceRNA mutual most useful network.RESULTS We used an RNA sequencing array to investigate the expression signatures of circRNAs in myocardial I/R injury using three samples from the I/R group and three samples from the sham group.A total of 142 upregulated and 121 downregulated circRNAs were found to be differentially expressed(fold change≥2,P<0.05).GO and KEGG functional analyses of these circRNAs were performed.GO analysis revealed that these circRNAs were involved mainly in cellular and intracellular processes.KEGG analysis demonstrated that 6 of the top 20 pathways were correlated with cell apoptosis.Furthermore,a circRNA-miRNA coexpression network and ceRNA network based on these genes were constructed,revealing that mmu-circ-0001452,mmu-circ-0001637,and mmu-circ-0000870 might be key regulators of myocardial I/R injury.CONCLUSION This research provides new insights into the mechanism of myocardial I/R,which mmu-circ-0001452,mmu-circ-0001637,and mmu-circ-0000870 are expected to be new therapeutic targets for myocardial I/R injury. 展开更多
关键词 Rna-sequencing circular RNA MicroRNA ceRNA Myocardial ischemia/reperfusion Bioinformatics analyses
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Promoting Tailored Hotel Recommendations Based on Traveller Preferences:A Circular Intuitionistic Fuzzy Decision Support Model
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作者 Sana Shahab Ibtehal Alazman +4 位作者 Ashit Kumar Dutta Mohd Anjum Vladimir Simic Zeljko Stevic Nouf Abdulrahman Alqahtani 《Computer Modeling in Engineering & Sciences》 2025年第5期2155-2183,共29页
With the increasing complexity of hotel selection,traditional decision-making models often struggle to account for uncertainty and interrelated criteria.Multi-criteria decision-making(MCDM)techniques,particularly thos... With the increasing complexity of hotel selection,traditional decision-making models often struggle to account for uncertainty and interrelated criteria.Multi-criteria decision-making(MCDM)techniques,particularly those based on fuzzy logic,provide a robust framework for handling such challenges.This paper presents a novel approach to MCDM within the framework of Circular Intuitionistic Fuzzy Sets(C-IFS)by combining three distinct methodologies:Weighted Aggregated Sum Product Assessment(WASPAS),an Alternative Ranking Order Method Accounting for Two-Step Normalization(AROMAN),and the CRITIC method(Criteria Importance Through Inter-criteria Correlation).To address the dynamic nature of traveler preferences in hotel selection,the study employs a comprehensive set of criteria encompassing aspects such as location proximity,amenities,pricing,customer reviews,environmental impact,safety,booking flexibility,and cultural experiences.The CRITIC method is used to determine the importance of each criterion by assessing intercriteria correlations.AROMAN is employed for the systematic evaluation of alternatives,considering their additive relationships and providing a weighted assessment.WASPAS further analyzes the results obtained from AROMAN,incorporating both positive and negative aspects for a comprehensive evaluation.The integration of C-IFS enhances the model’s ability to manage uncertainty and imprecision in the decision-making process.Through a case study,we demonstrate the effectiveness of this integrated approach,offering decision-makers valuable insights for selecting the most suitable hotel option in alignment with the diverse preferences of contemporary travelers.This research contributes to the evolving field of decision science by showcasing the practical applicability of these methodologies within a C-IFS framework for complex decision scenarios. 展开更多
关键词 Multi-criteria decision-making circular intuitionistic fuzzy sets hotel recommendations
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Extracellular vesicles circular RNA: A new perspective and clinical application potential for mediating chemoresistance in colorectal cancer
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作者 Shu-Zhen Liu Yan Liu +5 位作者 Chao-Li Wang Yu-Jiao Li Xiao-Qian Shan Wei-Li Gao Mei-Heng He Lan Zhao 《World Journal of Clinical Oncology》 2025年第7期163-175,共13页
Colorectal cancer(CRC)is a common and deadly malignancy worldwide,causing high morbidity and mortality rates.Chemoresistance continues to be the major barrier to the effective treatment of CRC.Circular RNA(circRNA),a ... Colorectal cancer(CRC)is a common and deadly malignancy worldwide,causing high morbidity and mortality rates.Chemoresistance continues to be the major barrier to the effective treatment of CRC.Circular RNA(circRNA),a recently identified class of non-coding RNA,has become an emerging focus in CRC research due to its abundant presence and stability in extracellular vesicles(EVs).The circRNA of EVs(EVs-circRNA)is closely associated with CRC progression and plays a pivotal role in chemoresistance mechanisms.This paper investigates the circRNA mechanism underlying different chemoresistance scenarios in CRC and explores the dual role of EVs-circRNA in mediating chemotherapy resistance.Furthermore,EVs-circRNA,a non-invasive biomarker for liquid biopsies,holds significant promise in clinical applications,ranging from early CRC diagnosis to monitoring disease progression and assessing prognosis.These studies provide a new perspective for uncovering CRC pathogenesis and lay the foundation for precision therapy and personalized treatment strategies for CRC.In the future,therapeutic strategies targeting EVs-circRNAs are anticipated to revolutionize CRC treatment,leading to improved therapeutic outcomes and enhanced quality of life for patients. 展开更多
关键词 Extracellular vesicles circular RNA Colorectal cancer Chemotherapy resistance Clinical application
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Experimental study on the buckling of composite cylinders with reinforced circular hole under hydrostatic pressure
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作者 Zhun Li Xinhu Zhang +3 位作者 Kechun Shen Jing Liu Jian Zhang Guang Pan 《Defence Technology(防务技术)》 2025年第2期231-247,共17页
In this paper,a type of reinforcing structure for composite shell with single and through hole is presented.The experimental tests for the composite shells without hole,with single hole and reinforced structure,with t... In this paper,a type of reinforcing structure for composite shell with single and through hole is presented.The experimental tests for the composite shells without hole,with single hole and reinforced structure,with through hole and reinforced structure subjected to hydrostatic pressure were carried out by the designed experimental test system.The mechanical responses of the composite shells under hydrostatic pressure are obtained by the high-speed camera and strain measurement.The results show that the entire deformation process of the shell can be divided into three:uniform compression,"buckling mode formation"and buckling.The"buckling mode formation"process is captured and reported for the first time.For the composite shell with single hole,the proposed reinforcing structure has a significant reinforcement effect on the shell and the buckling capacity of the shell is not weaker than the complete composite shell.For the composite shell with through hole,sealing effect can be achieved by the proposed reinforcing structure,but the buckling capacity of the shell after reinforcement can only reach 77%of the original buckling capacity. 展开更多
关键词 Composite cylindrical shell circular hole Reinforcing structure BUCKLING Hydrostatic pressure
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Extramural venous invasion in gastric cancer: 9.4T magnetic resonance imaging assessment and circular RNA functional analysis
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作者 Cai-Zhen Feng Xin-Yi Gou +7 位作者 Yi-Qun Liu Yu-Wei Xin Yin-Li Zhang Hui-Min Zhao Sheng-Cai Wei Nan Hong Yi Wang Jin Cheng 《World Journal of Gastroenterology》 2025年第14期94-105,共12页
BACKGROUND Extramural venous invasion(EMVI)is a critical prognostic factor in gastric cancer(GC);however,its detection and underlying molecular mechanisms remain underexplored.AIM To investigate the relationship betwe... BACKGROUND Extramural venous invasion(EMVI)is a critical prognostic factor in gastric cancer(GC);however,its detection and underlying molecular mechanisms remain underexplored.AIM To investigate the relationship between EMVI and expression of the circular RNA hsa_circ_0097977 in orthotopic GC mouse models.METHODS A retrospective analysis was conducted in addition to a preclinical animal study,involving 13 GC patients and 24 orthotopic GC mouse models,respectively.EMVI was assessed using axial T2-weighted fat suppression sequences on a 9.4T magnetic resonance imaging(MRI)with histopathological confirmation as the gold standard for EMVI.The impact of hsa_circ_0097977 on EMVI and GC cell function was evaluated.Statistical analyses comprised consistency,area under the curve analysis,correlation,χ^(2)/Fisher exact,and Mann-Whitney U/t-tests,with significance set at P<0.05.RESULTS EMVI was accurately detected using 9.4T MRI in orthotopic mouse models with an area under the curve of 0.843(sensitivity 78.6%,specificity 90.0%).MRI detected EMVI was the only imaging factor associated with distant metastasis(P=0.04).Furthermore,knockdown of hsa_circ_0097977 was the only factor associated with EMVI(P=0.043,0.038)and led to reduced invasion and increased apoptosis in GC cells.CONCLUSION EMVI,a risk factor for distant metastasis in GC,is detectable by 9.4T MRI and regulated by hsa_circ_0097977,making it a potential therapeutic target. 展开更多
关键词 Gastric cancer circular RNA Extramural venous invasion Orthotopic mouse model Magnetic resonance imaging Pathology Radiogenomics
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Circular RNA contributes to gastric cancer by targeting Wnt family member 2B as a competing endogenous RNA
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作者 Wei Bai Zong-Liang Guo +3 位作者 Jiang-Hong Guo Feng Li Peng Bu Juan Liu 《World Journal of Gastroenterology》 2025年第10期71-85,共15页
BACKGROUND As a non-coding RNA molecule,circular RNAs(circRNAs)have significant specificity,and existing data suggest a close relationship between them and the prognosis of patients with gastric cancer(GC).However,thi... BACKGROUND As a non-coding RNA molecule,circular RNAs(circRNAs)have significant specificity,and existing data suggest a close relationship between them and the prognosis of patients with gastric cancer(GC).However,this mechanism has no evidence yet.This article explores the functions of hsa_circRNA_102415 in the malignant behavior and potential downstream signaling of GC cells.The chosen approach is loss of signal and functional gain.AIM To investigate and analyze the relationship between hsa_circRNA_102415 and GC and explore its specific role.Results provide reference for other researchers to develop targeted treatment plans.METHODS The gene expression omnibus(GEO)database can be used to obtain the microarray dataset GSE83521.Data were analyzed using the GEO2R tool to identify differences in circRNAs between normal and GC samples.Quantitative real-time polymerase chain reaction was used to detect differentially expressed genes in GC tissue samples and adjacent cancer tissue samples.GC cells were transfected with small interfering-hsa_circRNA_104415 and plasmid DNA(pcDNA)-hsa_ircRNA_102415.Multiple detection methods,such as Transwell and cell counting kit 8,were used to evaluate cellular physiological activities,including cell invasion and proliferation.The relationship between Wnt family members 2B,microRNA(miR)-4529-5p,etc.,including argonaute 2-RNA immunoprecipitation and luciferase reporter genes was analyzed.Rescue experiments were conducted to analyze and explore the relationship between the malignant behavior of GC cells and hsa_circRNA_102415.RESULTS GEO2R analysis confirmed that hsa_circRNA_102415 had significantly higher expression levels in disease tissues.hsa_circRNA_102415 and miR-4529-5p showed a negative correlation in disease cells,suggesting that hsa_circRNA_102415 upregulated WNT2B expression in GC cells as a competing endogenous RNA for miR-4529-5p.miR-4529-5p mimic or small interfering-WNT2B reversed the effects of pcDNA-hsa_circRNA_102415 or miR-4529-5p inhibitor on cell malignant functions.CONCLUSION miR-4529-5p was used to successfully activate the potential of WNT2B,clarify the role of hsa_circRNA_102415 in GC cells,and provide reference for other researchers to develop targeted treatment plans. 展开更多
关键词 Competing endogenous RNA Wnt family member 2B MicroRNA-4529-5p circular RNAs Gastric cancer
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Circular RNA circAGAP1 promotes sunitinib sensitivity in renal cell carcinoma via sponging multiple PDGFR-targeted miRNAs
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作者 QI LV GANGMIN WANG +8 位作者 YI HONG TIANYI ZHU SHUANG QIN SAIFEI SUN YUTING WANG YAOHUA LIU QING ZHANG CHUNHUI MA PEIJUN WANG 《Oncology Research》 2025年第2期407-420,共14页
Background:Sunitinib resistance is a major challenge in advanced renal cell carcinoma(RCC).Clinically,elucidating the underlying mechanisms and developing practical countermeasures for sunitinib resistance in RCC is d... Background:Sunitinib resistance is a major challenge in advanced renal cell carcinoma(RCC).Clinically,elucidating the underlying mechanisms and developing practical countermeasures for sunitinib resistance in RCC is desirable.In previous studies,we found that circAGAP1 expression was significantly upregulated in clear cell RCC(ccRCC)and was strongly associated with poor prognosis.However,the role of circAGAP1 in sunitinib resistance in ccRCC remains unclear.Methods:We used public databases for bioinformatics analysis to identify the binding targets of circAGAP1.Additionally,the effects of circAGAP1 on the proliferation,clonogenesis,apoptosis,and migration of ccRCC cells were analyzed using quantitative real-time PCR,cell counting kit-8 assays,migration and apoptosis assays,and colony formation assays.Furthermore,RNA immunoprecipitation,dual-luciferase reporter,and fluorescence in situ hybridization assays were used to explore the molecular mechanism.Results:In this study,circAGAP1 exhibited higher expression in sunitinib-sensitive ccRCC cells and inhibited the clonogenesis,proliferation,and migration of ccRCC cells after sunitinib treatment.Mechanical studies revealed that circAGAP1 regulated the expression of sunitinib target platelet-derived growth factor receptor by acting as a microRNA sponge that suppresses miR-149-5p,miR-455-5p,and miR-15a-5p simultaneously.Overexpression of these three miRNAs reversed circAGAP1-mediated sunitinib sensitivity in ccRCC.Conclusions:In summary,our findings indicate that circAGAP1 may serve as a promising biomarker to predict sunitinib sensibility and a therapeutic target in ccRCC. 展开更多
关键词 Renal cell carcinoma Sunitinib resistance circular RNA circAGAP1 MiR-149-5p MiR-455-5p MiR-15a-5p
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基于时域同步平均的Circular图分析方法及齿轮故障智能诊断研究
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作者 胥永刚 张翼飞 +1 位作者 孙国栋 张坤 《机械强度》 北大核心 2025年第6期11-16,共6页
齿轮Circular图是用于与时域同步平均(Time Synchronous Averaging,TSA)相结合的一种结果呈现方法,可以将TSA提取到的齿轮啮合振动波形直观、清晰地展现出来。针对齿轮Circular图绘制参数设置和其缺少量化指标的问题,提出了用于波形边... 齿轮Circular图是用于与时域同步平均(Time Synchronous Averaging,TSA)相结合的一种结果呈现方法,可以将TSA提取到的齿轮啮合振动波形直观、清晰地展现出来。针对齿轮Circular图绘制参数设置和其缺少量化指标的问题,提出了用于波形边缘识别的F_(i)指标和基于Hu氏不变矩的Y_(i)指标。首先,使用TSA算法提取出齿轮啮合振动信号,通过计算最小F_(i)指标确定振动信号波形的上、下边缘;其次,利用上、下边缘参数绘制齿轮Circular图;再次,将齿轮Circular图分割为4个部分,通过计算分割后图片的Hu氏不变矩得到齿轮Circular图的Y_(i)指标;最后,基于从齿轮Circular图中提取出的Y_(i)和F_(i)指标,使用K最近邻(K-Nearest Neighbor,KNN)分类器对齿轮振动信号进行分类。仿真信号及齿轮断齿、裂纹故障信号的处理结果表明了该方法的有效性。 展开更多
关键词 齿轮箱 齿轮circular 特征指标 智能故障诊断
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富Ce稀土永磁材料微观结构与性能研究 被引量:1
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作者 王江 李莎 +7 位作者 付刚 陈东雯 甘家毅 黄清芳 马垒 张康斌 黄伟明 饶光辉 《大众科技》 2025年第3期115-117,122,共4页
文章采用真空熔炼甩带法制备6种不同成分的富Ce稀土速凝薄带合金样品,利用X射线衍射仪、磁性能测试仪等设备,开展甩带片物相结构分析、微观组织结构分析和磁性能测试。结果表明:富Ce稀土永磁合金甩带片主要由硬磁相(Nd,Ce)_(2)Fe_(14)B... 文章采用真空熔炼甩带法制备6种不同成分的富Ce稀土速凝薄带合金样品,利用X射线衍射仪、磁性能测试仪等设备,开展甩带片物相结构分析、微观组织结构分析和磁性能测试。结果表明:富Ce稀土永磁合金甩带片主要由硬磁相(Nd,Ce)_(2)Fe_(14)B、软磁相α-Fe以及少量的富稀土fcc-Ce相和dhcp-Nd相构成。其中,(Nd_(0.7)Ce_(0.3))_(16)Fe_(78)B_(6)速凝薄带合金样品的方形度最好,且最大磁能积达到7.26 MGOe。研究为高丰度稀土永磁材料的开发提供了基础实验数据。 展开更多
关键词 ce稀土 速凝薄带 磁性能
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LaBr_(3)(Ce)探测器性能测试实验设计
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作者 罗文 李鑫祥 +4 位作者 时正佳 罗凯军 刘泓辰 张书桐 宋良宏 《实验技术与管理》 北大核心 2025年第7期110-116,共7页
随着核科学技术的发展,核物理和核探测领域对高性能探测器的需求不断增加,因此在核类专业实验课程中加入前沿的探测器测试内容至关重要。这有助于学生提前接触科研设备,为将来从事科研工作打下基础,并通过实验室实践将理论与实际操作相... 随着核科学技术的发展,核物理和核探测领域对高性能探测器的需求不断增加,因此在核类专业实验课程中加入前沿的探测器测试内容至关重要。这有助于学生提前接触科研设备,为将来从事科研工作打下基础,并通过实验室实践将理论与实际操作相结合。该文设计了包括基于LaBr_(3)(Ce)的探测系统搭建、本底测量、能量刻度、能量分辨率刻度以及符合测量等内容的实验,并对实验结果进行了分析。研究结果表明,这项实验能够准确测量核素能谱,并能通过数据计算核素活度,有较高应用价值。 展开更多
关键词 LaBr_(3)(ce)探测器性能测试 符合测量 学术型人才培养 实验设计
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稀土(Ce/Y)与Al-5Ti-B复合添加对6061铝合金显微组织和力学性能的影响
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作者 丁万武 孙建英 +3 位作者 徐梅 张利鹏 安家志 余海存 《有色金属(中英文)》 北大核心 2025年第7期1096-1104,共9页
采用光学显微镜、扫描电子显微镜、万能试验机和显微硬度测试等方法,研究了在6061铝合金中添加稀土Ce/Y元素及Al-5Ti-B中间合金对其显微组织和力学性能的影响。结果表明,当向铸态6061铝合金中添加0.20%Al-5Ti-B和0.15%Y时,其力学性能最... 采用光学显微镜、扫描电子显微镜、万能试验机和显微硬度测试等方法,研究了在6061铝合金中添加稀土Ce/Y元素及Al-5Ti-B中间合金对其显微组织和力学性能的影响。结果表明,当向铸态6061铝合金中添加0.20%Al-5Ti-B和0.15%Y时,其力学性能最优,抗拉强度、伸长率、显微硬度分别由141.3 MPa、8.3%、58.1 HV提高至179.5 MPa、20.0%、69.7 HV,试样的平均晶粒尺寸由118.2μm减小至57.79μm,且β-AlFeSi和Mg2Si相的形貌由长针状转变为短棒状或颗粒状,降低了对基体的割裂作用。添加0.20%Al-5Ti-B和0.15%Y的6061试样综合性能的提高是晶粒细化和β-AlFeSi和Mg2Si相形貌改善综合作用的结果。 展开更多
关键词 6061铝合金 稀土ce 稀土Y 显微组织 力学性能
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中国西北地区770 BCE-1000 CE疫灾的时空特征与影响因子
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作者 龚胜生 杜雨涵 《华中师范大学学报(自然科学版)》 北大核心 2025年第5期755-764,共10页
中国西北地区是欧亚大陆贸易往来和疫病传输的重要通道.本文采用时间序列分析、GIS空间分析、因子相关分析等方法对中国西北地区770 BCE—1000 CE的疫灾时空特征与影响因子进行研究,结果表明:1)770 BCE—1000 CE,西北地区共有38个疫灾之... 中国西北地区是欧亚大陆贸易往来和疫病传输的重要通道.本文采用时间序列分析、GIS空间分析、因子相关分析等方法对中国西北地区770 BCE—1000 CE的疫灾时空特征与影响因子进行研究,结果表明:1)770 BCE—1000 CE,西北地区共有38个疫灾之年,疫灾频度仅2.15%,低于全国平均水平;疫灾多在春、秋季流行,长期呈波动上升趋势,与同期全国特征一致.2)770 BCE—1000 CE,西北地区疫灾集中于人口相对稠密的东南部,农耕区疫灾多于畜牧区,交通沿线为疫灾高发带,关中平原的宝鸡—西安—渭南一带为热点区,兰州—西宁一线、延安—榆林一线为冷点区.3)770 BCE—1000 CE,西北地区疫灾时空特征的形成受气候、灾害和人类活动多重因子的影响:寒冷干燥期较温暖湿润期疫灾多发;灾害对疫灾有显著激发作用,灾害频繁期也是疫灾频繁期,灾害多发区也是疫灾多发区.上述研究结果,对于研究干旱半干旱地区疫灾的发生与流行机制具有重要参考价值. 展开更多
关键词 疫灾 时空特征 影响因子 西北地区 770 Bce—1000 ce
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多级退火对高Ce含量烧结磁体磁性能及磁硬化机制的影响
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作者 岳明 岳鹏昊 +2 位作者 张乐乐 李玉卿 刘卫强 《金属功能材料》 2025年第1期1-8,共8页
近年来,高Ce含量的磁体成为了永磁材料的研究热点。高Ce含量的(Nd,Ce)-Fe-B磁体的晶界结构与传统的Nd-Fe-B磁体有着很大的差异,而退火是优化晶界、提升磁性能的关键。在传统的二级退火基础上,优化为三级退火,系统地研究了每一级退火对(C... 近年来,高Ce含量的磁体成为了永磁材料的研究热点。高Ce含量的(Nd,Ce)-Fe-B磁体的晶界结构与传统的Nd-Fe-B磁体有着很大的差异,而退火是优化晶界、提升磁性能的关键。在传统的二级退火基础上,优化为三级退火,系统地研究了每一级退火对(Ce_(0.6)Nd_(0.4))_(33)Fe_(bal)Al_(1)Co_(0.5)Cu_(0.35)Ga_(0.35)B_(0.96)磁体微观结构以及磁性能的影响。结果表明:经过三级退火后,磁体矫顽力从6.55增至9.35 kOe,增幅高达42.7%;方形度从78%优化至95%。磁性能大幅提升的根本原因在于,在退火的过程中消除了异形主相晶粒,调控了晶界CeFe_(2)相以及富RE相的分布,改善了晶间相的浸润性,促使形成了连续且较厚的具有良好磁隔离效果薄层晶界。 展开更多
关键词 (Nd ce)-Fe-B ceFe_(2)相 富RE相 退火 矫顽力 磁性能
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基于电子束辐射制备磁性离子交换树脂及其吸附Ce^(3+)研究
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作者 赵媛 高洁 +2 位作者 胡国文 韩小兵 陈涛 《稀土》 北大核心 2025年第2期53-61,共9页
以甲基丙烯酸甲酯(MMA)为单体,二乙烯苯(DVB)为交联剂,液体石蜡为制孔剂,纳米Fe_(3)O_(4)为磁源,通过悬浮聚合法制备了磁性多孔PMMA微球。再经电子束共辐射接枝对苯乙烯磺酸钠(SSS)制得强酸性PMMA-SSS离子交换树脂。对制备的离子交换树... 以甲基丙烯酸甲酯(MMA)为单体,二乙烯苯(DVB)为交联剂,液体石蜡为制孔剂,纳米Fe_(3)O_(4)为磁源,通过悬浮聚合法制备了磁性多孔PMMA微球。再经电子束共辐射接枝对苯乙烯磺酸钠(SSS)制得强酸性PMMA-SSS离子交换树脂。对制备的离子交换树脂进行了FTIR、TG、XRD表征,辅证了PMMA-SSS离子交换树脂的成功制备;探讨了其对Ce^(3+)的吸附性能,结果表明在辐射吸收剂量为160 kGy, pH=5时吸附效果最佳,吸附量为305.09 mg/g,且PMMA-SSS离子交换树脂对Ce^(3+)的吸附符合准二级动力学模型,表明吸附过程是化学吸附。 展开更多
关键词 磁性离子交换树脂 铈离子 辐射接枝 吸附 对苯乙烯磺酸钠
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Ce对AH36钢海洋环境中腐蚀行为的影响 被引量:2
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作者 李想 刘香军 +2 位作者 杨昌桥 任慧平 刘玉宝 《中国冶金》 北大核心 2025年第5期106-118,共13页
海洋环境下,船板钢易发生腐蚀,严重危害材料的服役安全。为了研究稀土Ce对AH36船板钢在海洋环境中耐腐蚀性能的影响,采用SEM、XRD、EPMA及电化学测试等手段分析了Ce对AH36钢中夹杂物的影响及其在模拟海洋环境下的腐蚀行为。研究结果显示... 海洋环境下,船板钢易发生腐蚀,严重危害材料的服役安全。为了研究稀土Ce对AH36船板钢在海洋环境中耐腐蚀性能的影响,采用SEM、XRD、EPMA及电化学测试等手段分析了Ce对AH36钢中夹杂物的影响及其在模拟海洋环境下的腐蚀行为。研究结果显示,添加Ce后,钢中的Al2O3、MnS、TiN夹杂物转变为椭球形的Ce-O、Ce-Ti-N-O-S夹杂物,钢中夹杂物的尺寸由2.5~6.0μm减小至1~2μm;当Ce的质量分数为0.009%、0.034%时,试验钢中夹杂物的数量密度从49mm^(-2)分别提高至54mm^(-2)和72mm^(-2),尺寸小于5μm的夹杂物所占比例从67%分别提高至82%和76%。质量分数为3.5%NaCl溶液浸泡试验结果表明,Ce可以提高α-FeOOH和Fe_(3)O_(4)在腐蚀产物中的占比;Ce的质量分数为0.009%和0.034%时,腐蚀产物中α-FeOOH和Fe_(3)O_(4)的质量分数之和与γ-FeOOH的质量分数之比(α^(*)/γ^(*))较未添加Ce时的1.09分别增大至2.27和1.64;浸泡21d时,Ce的质量分数为0.009%和0.034%,试验钢的腐蚀电流密度由未添加Ce时的2.652A/cm^(2)分别减小至2.127、2.209A/cm^(2);Ce的质量分数为0.009%时AH36钢的耐蚀性较好。 展开更多
关键词 稀土ce AH36船板钢 夹杂物 腐蚀产物 X射线衍射
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HPW@UiO-66(Ce)复合材料的制备及可见光催化降解四环素 被引量:1
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作者 王寒蕊 李春光 +3 位作者 杜晨阳 王强 王聪 柳雨晴 《精细化工》 北大核心 2025年第2期411-419,448,共10页
利用水热合成法将磷钨酸(HPW)负载在铈基金属有机骨架材料〔UiO-66(Ce)〕上,制备了HPW@UiO-66(Ce)复合材料。采用SEM、XRD、FTIR、BET、UV-Vis DRS、XPS对HPW@UiO-66(Ce)进行了表征。考察了HPW@UiO-66(Ce)可见光催化降解四环素(TC)的性... 利用水热合成法将磷钨酸(HPW)负载在铈基金属有机骨架材料〔UiO-66(Ce)〕上,制备了HPW@UiO-66(Ce)复合材料。采用SEM、XRD、FTIR、BET、UV-Vis DRS、XPS对HPW@UiO-66(Ce)进行了表征。考察了HPW@UiO-66(Ce)可见光催化降解四环素(TC)的性能,探讨了其光催化降解机理。结果表明,HPW@UiO-66(Ce)拓宽了UiO-66(Ce)可见光吸收范围,从470 nm增至500 nm;HPW的负载降低了UiO-66(Ce)的比表面积,但对其孔径没有影响。由m(H_(3)PO_(4)•12WO_(3)•xH_(2)O)∶m〔UiO-66(Ce)〕=7∶5〔UiO-66(Ce)0.5 g〕制备的HPW@UiO-66(Ce)-0.7具有最佳的光催化降解TC性能,在可见光照90 min、投加量〔HPW@UiO-66(Ce)-0.7质量与TC溶液体积之比,下同〕为0.50 g/L时,对质量浓度60 mg/L、pH=7的TC降解率可达到96.4%。羟基自由基、空穴是HPW@UiO-66(Ce)-0.7光催化降解TC过程中主要活性物种,超氧自由基也参与此过程。 展开更多
关键词 磷钨酸 UiO-66(ce) 四环素 光催化剂 降解 水处理技术
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