检索结果-南通市图书馆

DEM investigation of strength and critical state behaviours of granular materials under true triaxial loadings

Particuology 2024年第2期85卷 198-212页

作者： Minyi Zhu Guobin Gong Jun xia Stephen Wilkinson Department of Civil Engineering Xi'an Jiaotong-Liverpool UniversityChina Department of Civil Engineering and Industrial Design University of LiverpoolLiverpoolUK Faculty of Engineering and Information Sciences University of Wollongong in DubaiUnited Arab Emirates

This paper investigates the strength and critical state(CS)behaviours of granular materials via DEM simulations of true triaxial drained tests under three different loading modes including constant b(in-termediate stress ratio)tests with constantσ'1(major principal stress),constant p(mean pressure)and constantσ'3(minor principal stress)*** this end,a series of samples are generated with the same particle size distribution,and with the confining stresses ranging from 100 kPa to 900 *** CS is achieved for all *** the macroscopic behaviours and the microscopic behaviours are examined and compared considering different loading modes,confining stresses and intermediate stress ratios(b).The critical state lines(CSLs)are found to be unique and independent of the loading modes,but dependent on the b *** CSLs with b=0 and b=1 form the two boundaries of CSLs respectively beyond which CSLs under all other b tests cannot go *** different strength criteria are examined and compared in terms of both peak and CS *** Mohr-Coulomb strength criterion is found to be only suitable for axisymmetric loading *** Lade-Duncan criterion is only suitable for describing peak strengths,which is dependent on the loading modes and confining *** Satake criterion and Matsuoka-Nakai criterion are the more appropriate strength criteria for describing CS failures,indicating that the CS values of both the Satake parameter and the Matsuoka-Nakai parameter describe an inherent property that characterizes the CS failure for a given type of *** CS mechanical coordination number is fitted by a curved line for a given b value,which is unique regardless of the loading *** peak and CS values of both major and minor principal fabric tensors decrease with increasing b values,while they increase with increasing b values for the intermediate principal fabric tensor.

关键词： Discrete element method Intermediate stress ratio Dilation Critical state Failure criterion

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Numerical simulations for radon migration and exhalation behavior during measuring radon exhalation rate with closed-loop method

引用

Nuclear Science and Techniques 2024年第1期35卷 81-95页

作者： Ming xia Yong-Jun Ye Shu-Yuan Liu School of Resources Environment and Safety Engineering University of South ChinaHengyang 421001China Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy University of South ChinaHengyang 421001China

Accurate measurements of the radon exhalation rate help identify and evaluate radon risk regions in the *** these measurement methods,the closed-loop method is frequently ***,traditional experiments are insufficient or cannot analyze the radon migration and exhalation patterns at the gas–solid interface in the accumulation *** CFD-based technique was applied to predict the radon concentration distribution in a limited space,allowing radon accumulation and exhalation inside the chamber intuitively and *** this study,three radon exhalation rates were defined,and two structural ventilation tubes were designed for the *** consistency of the simulated results with the variation in the radon exhalation rate in a previous experiment or analytical solution was *** effects of the vent tube structure and flow rate on the radon uniformity in the chamber;permeability,insertion depth,and flow rate on the radon exhalation rate and the effective diffusion coefficient on back-diffusion were *** on the results,increasing the inser-tion depth from 1 to 5 cm decreased the effective decay constant by 19.55%,whereas the curve-fitted radon exhalation rate decreased(lower than the initial value)as the deviation from the initial value increased by approximately 7%.Increasing the effective diffusion coefficient from 2.77×10^(-7) to 7.77×10^(-6) m^(2) s^(-1) made the deviation expand from 2.14 to 15.96%.The conclusion is that an increased insertion depth helps reduce leakage in the chamber,subject to notable back-diffusion,and that the closed-loop method is reasonably used for porous media with a low effective diffusion coefficient in view of the back-diffusion *** CFD-based simulation is expected to provide guidance for the optimization of the radon exhalation rate measurement method and,thus,the accurate measurement of the radon exhalation rate.

关键词： Radon exhalation Numerical simulation Accumulation chamber

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Efficient energy transfer from self-trapped excitons to Mn^(2+) dopants in CsCdCl_(3):Mn^(2+) perovskite nanocrystals

引用

International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1456-1461页

作者： Anran Zhang Xinquan Zhou Ranran Gu Zhiguo xia State Key Laboratory of Luminescent Materials and Devices Guangdong Provincial Key Laboratory of Fiber Laser Materials and Applied TechniquesSchool of Materials Science and EngineeringSouth China University of TechnologyGuangzhou 510641China School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510641China

Mn^(2+)doping has been adopted as an efficient approach to regulating the luminescence properties of halide perovskite nano-crystals(NCs).However,it is still difficult to understand the interplay of Mn^(2+)luminescence and the matrix self-trapped exciton(STE)emission *** this study,Mn^(2+)-doped CsCdCl_(3) NCs are prepared by hot injection,in which CsCdCl_(3) is selected because of its unique crystal structure suitable for STE *** blue emission at 441 nm of undoped CsCdCl_(3) NCs originates from the defect states in the ***^(2+)doping promotes lattice distortion of CsCdCl_(3) and generates bright orange-red light emission at 656 *** en-ergy transfer from the STEs of CsCdCl_(3) to the excited levels of the Mn^(2+)ion is confirmed to be a significant factor in achieving efficient luminescence in CsCdCl_(3):Mn^(2+)*** work highlights the crucial role of energy transfer from STEs to Mn^(2+)dopants in Mn^(2+)-doped halide NCs and lays the groundwork for modifying the luminescence of other metal halide perovskite NCs.

关键词： perovskite nanocrystals self-trapped excitons luminescence energy transfer

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Eigenfrequency analysis of bridges using a smartphone and a novel low-cost accelerometer prototype

引用

Frontiers of Structural and Civil Engineering 2024年第2期18卷 202-215页

作者： Seyedmilad KOMARIZADEHASL Ye xia Mahyad KOMARY Fidel LOZANO Department of Civil and Environment Engineering Universitat Politècnica de CatalunyaBarcelona 08034Spain Department of Bridge Engineering Tongji UniversityShanghai 200092China Department of Civil Engineering Universidad de Castilla-La ManchaCiudad Real 13071Spain

Researchers are paying increasing attention to the development of low-cost and microcontroller-based accelerometers,in order to make structural health monitoring feasible for conventional bridges with limited monitoring *** with the low-cost sensor development,the use of the embedded accelerometers of smartphones for eigenfrequency analysis of bridges is becoming popular in the civil engineering *** paper,for the first time in the literature,studies these two promising technologies by comparing the noise density and eigenfrequency analysis of a self-developed,validated and calibrated low-cost Internet of things based accelerometer LARA(low cost adaptable reliable accelerometer)with those of a state of the art smartphone(iPhone XR).The eigenfrequency analysis of a footbridge in San Sebastian,Spain,showed that the embedded accelerometer of the iPhone XR can measure the natural frequencies of the under study bridge.

关键词： smartphone modal analysis eigenfrequency analysis low-cost accelerometers Arduino Raspberry Internet of things

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Heteroepitaxial growth of Au@Pd core–shell nanocrystals with intrinsic chiral surfaces for enantiomeric recognition

引用

Rare Metals 2024年第1期43卷 225-235页

作者： Feng-xia Wu Feng-Hua Li xia-Li Lv Qi-xian Zhang Guo-Bao Xu Wen-Xin Niu State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Shaoxing Institute of Technology Shanghai UniversityShaoxing 312000China University of Science and Technology of China Hefei 230026China School of Materials Science and Engineering Shanghai UniversityShanghai 200436China Zhejiang Institute of Advanced Materials Shanghai UniversityJiashan 314113China University of Chinese Academy of Sciences Beijing 100039China

Noble metal surfaces with intrinsic chirality serve as an ideal candidate for investigating enantioselective chemistry due to their superior chemical durability and high catalytic ***,significant advance has been made in synthesizing metal nanocrystals with intrinsic ***,the majority reports are limited to ***,through a heteroepitaxial growth strategy,the synthesis of metal nanocrystals with intrinsic chirality to palladium was extended for the first time and their application in enantioselective recognition was *** heteroepitaxial growth strategy allows for transferring the chirality of homochiral Au nanocrystals to Au@Pd core–shell *** employing the chiral Au@Pd nanocrystals as enantiomeric recognizing elements,a series of electrochemical sensors for chiral discrimination were *** optimal conditions,the peak potential between D-dihydroxyphenylalanine(D-DOPA)and L-dihydroxyphenylalanine(L-DOPA)is about 80 m V,and the peak current of D-DOPA is 2 times as much as that of L-DOPA,which enables the determination of the enantiomeric excess(EE,%)of ***,this report not only introduces a heteroepitaxial growth strategy to synthesize metal nanocrystals with intrinsic chirality,but also demonstrates the superior capability of integrating intrinsic chirality and catalytic properties into metal nanocrystals for chiral recognition.

关键词： Core–shell nanostructures Chirality transfer Electrochemical sensors Chiral recognition Chiroplasmonics

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effects of psychological nursing in Parkinson's related depression patients undergoing functional magnetic resonance imaging:A randomized controlled trial

引用

World Journal of Clinical Cases 2024年第17期12卷 3086-3093页

作者： xiao-xia Zhang xiao-Hui Zhang Yan-chao Dong Department of Internal Medicine The First hospital of QinhuangdaoQinhuangdao 066000Hebei ProvinceChina Department of Gastroscope The First hospital of QinhuangdaoQinhuangdao 066000Hebei ProvinceChina Medical Imaging Center The First hospital of QinhuangdaoQinhuangdao 066000Hebei ProvinceChina

BACKGROUND Patients with Parkinson’s disease(PD)often experience depression,and some may require magnetic resonance imaging(MRI)for diagnosis,which can lead to MRI failure due to *** To explore the value of psychological interventions in successfully completing functional MRI scans of the brain for PD-related *** Ninety-six patients with PD were randomly divided into two *** control group(47 patients)received general care,and the experimental group(49 patients)received general care combined with psychological *** Unified Parkinson's Disease Assessment Scale(UPDRS),Hamilton Depression Scale(HAMD),and Geriatric Depression Scale(GDS)-15 scores,heart rate,systolic blood pressure,and MRI-Anxiety Questionnaire(MRI-AQ)scores before and after the scan were *** completion rate of magnetic resonance(MR)scanning,scanning duration,and image quality scores were *** Before scanning,no statistically significant difference was observed between the two groups in terms of heart rate,systolic blood pressure,and UPDRS,HAMD,GDS-15,and MRI-AQ *** scanning,systolic blood pressure,MRI-AQ score,and scan time in the experimental group were significantly lower than those in the control group,whereas the scan completion rate and image quality score were significantly higher than those in the control *** Psychological nursing interventions are helpful in alleviating PD-related depression and assessing MR depression scores and may be helpful in the successful completion of functional MRI scans of the patient's brain.

关键词： Magnetic resonance imaging Psychological nursing Parkinson's disease Depression Claustrophobia

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

BCCLR:A Skeleton-Based Action Recognition with Graph Convolutional Network Combining Behavior Dependence and Context Clues

引用

Computers, Materials & Continua 2024年第3期78卷 4489-4507页

作者： Yunhe Wang Yuxin xia Shuai Liu College of Information Science and Engineering Institute of Interdisciplinary StudiesHunan Normal UniversityChangsha410081China School of Educational Sciences Institute of Interdisciplinary StudiesHunan Normal UniversityChangsha410081China

In recent years,skeleton-based action recognition has made great achievements in Computer Vision.A graph convolutional network(GCN)is effective for action recognition,modelling the human skeleton as a spatio-temporal *** GCNs define the graph topology by physical relations of the human ***,this predefined graph ignores the spatial relationship between non-adjacent joint pairs in special actions and the behavior dependence between joint pairs,resulting in a low recognition rate for specific actions with implicit correlation between joint *** addition,existing methods ignore the trend correlation between adjacent frames within an action and context clues,leading to erroneous action recognition with similar ***,this study proposes a learnable GCN based on behavior dependence,which considers implicit joint correlation by constructing a dynamic learnable graph with extraction of specific behavior dependence of joint *** using the weight relationship between the joint pairs,an adaptive model is *** also designs a self-attention module to obtain their inter-frame topological relationship for exploring the context of *** the shared topology and the multi-head self-attention map,the module obtains the context-based clue topology to update the dynamic graph convolution,achieving accurate recognition of different actions with similar *** experiments on public datasets demonstrate that the proposed method achieves better results and realizes higher quality representation of actions under various evaluation protocols compared to state-of-the-art methods.

关键词： Action recognition deep learning GCN behavior dependence context clue self-attention

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Interleukins in Epilepsy:Friend or Foe

引用

Neuroscience Bulletin 2024年第5期40卷 635-657页

作者： Yuan Dong xia Zhang Ying Wang Neuropsychiatry Research Institute The Affiliated Hospital of Qingdao UniversityQingdao UniversityQingdao266000China Program in Cellular and Molecular Medicine Boston Children’s HospitalBostonMA02115USA

Epilepsy is a chronic neurological disorder with recurrent unprovoked seizures,affecting~65 million *** in patients with epilepsy and animal models suggests a contribution of neuroinflammation to epileptogenesis and the development of ***(ILs),as one of the major contributors to neuroinflammation,are intensively studied for their association and modulatory effects on ictogenesis and *** are commonly divided into pro-and anti-inflammatory cytokines and therefore are expected to be pathogenic or neuroprotective in ***,both protective and destructive effects have been reported for many *** may be due to the complex nature of ILs,and also possibly due to the different disease courses that those ILs are involved *** this review,we summarize the contributions of different ILs in those processes and provide a current overview of recent research advances,as well as preclinical and clinical studies targeting ILs in the treatment of epilepsy.

关键词： Epilepsy Interleukins Neuroinflammation

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Differences in insomnia-related self-reported outcomes among elderly hospitalized patients

引用

World Journal of Psychiatry 2024年第5期14卷 686-694页

作者： xia Ding Ling-xia Qi Dong-Yun Sun Department of Gangzha General Medical Center The Affiliated Hospital of Nantong UniversityNantong 226000Jiangsu ProvinceChina Department of Anesthesiology and Surgery The Affiliated Hospital of Nantong UniversityNantong 226000Jiangsu ProvinceChina Department of Ophthalmic Surgery Room The Affiliated Hospital of Nantong UniversityNantong 226000Jiangsu ProvinceChina

Insomnia is among the most common sleep disorders *** in older adults is a social and public health *** affects the physical and mental health of elderly hospitalized patients and can aggravate or induce physical *** subjective feelings and providing reasonable and standardized care for elderly hospitalized patients with insomnia are urgent *** To explore the differences in self-reported outcomes associated with insomnia among elderly hospitalized *** One hundred patients admitted to the geriatric unit of our hospital between June 2021 and December 2021 were included in this ***-reported symptoms were assessed using the Athens Insomnia Scale(AIS),Generalized Anxiety Disorder Scale-7(GAD-7),Geriatric Depression Scale-15(GDS-15),Memorial University of Newfoundland Scale of Happiness(MUNSH),Barthel Index Evaluation(BI),Morse Fall Scale(MFS),Mini-Mental State Examination,and the Short Form 36 Health Survey Questionnaire(SF-36).Correlation coefficients were used to analyze the correlation between sleep quality and self-reported *** of insomnia was analyzed using Logistic regression *** Nineteen patients with AIS≥6 were included in the insomnia group,and the incidence of insomnia was 19%(19/100).The remaining 81 patients were assigned to the non-insomnia *** were significant differences between the two groups in the GDA-7,GDS-15,MUNSH,BI,MFS,and SF-36 items(P<0.05).Patients in the insomnia group were more likely to experience anxiety,depression,and other mental illnesses,as well as difficulties with everyday tasks and a greater risk of falling(P<0.05).Subjective well-being and quality of life were poorer in the insomnia group than in the control *** AIS scores positively correlated with the GAD-7,GDS-15,and MFS scores in elderly hospitalized patients with insomnia(P<0.05).Logistic regression analysis showed that GDS-15≥5 was an independent risk factor for ins

关键词： Elderly hospitalized patients Insomnia Self-reported outcomes Symptoms Subjective feelings Correlation

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Early proactive monitoring of DNA-thioguanine in patients with Crohn’s disease predicts thiopurine-induced late leucopenia in NUDT15/TPMT normal metabolizers

引用

World Journal of Gastroenterology 2024年第12期30卷 1751-1763页

作者： Ting Yang Kang chao xia Zhu Xue-Ding Wang Sumyuet Chan Yan-Ping Guan Jing Mao Pan Li Shao-Xing Guan Wen Xie xiang Gao Min Huang School of Pharmaceutical Sciences Sun Yat-sen UniversityGuangzhou 510006Guangdong ProvinceChina Institute of Clinical Pharmacology Sun Yat-sen UniversityGuangzhou 510006Guangdong ProvinceChina Department of Gastroenterology The Sixth Affiliated HospitalSun Yat-sen UniversityGuangzhou 510655Guangdong ProvinceChina Department of Pharmacy The First Affiliated HospitalSun Yat-sen UniversityGuangzhou 510080Guangdong ProvinceChina Center for Pharmacogenetics and Department of Pharmaceutical Sciences University of PittsburghPittsburghPA 15261United States

BACKGROUND Thiopurine-induced leucopenia significantly hinders the wide application of *** optimization guided by nudix hydrolase 15(NUDT15)has significantly reduced the early leucopenia rate,but there are no definitive biomarkers for late risk leucopenia *** To determine the predictive value of early monitoring of DNA-thioguanine(DNATG)or 6-thioguanine nucleotides(6TGN)for late leucopenia under a NUDT15-guided thiopurine dosing strategy in patients with Crohn’s disease(CD).METHODS Blood samples were collected within two months after thiopurine initiation for detection of metabolite *** leucopenia was defined as a leukocyte count<3.5×10^(9)/L over two *** Of 148 patients studied,late leucopenia was observed in 15.6%(17/109)of NUDT15/thiopurine methyltransferase(TPMT)normal and 64.1%(25/39)of intermediate *** patients suffering late leucopenia,early DNATG levels were significantly higher than in those who did not develop late leucopenia(P=4.9×10^(-13)).The DNATG threshold of 319.43 fmol/μg DNA could predict late leucopenia in the entire sample with an area under the curve(AUC)of 0.855(sensitivity 83%,specificity 81%),and in NUDT15/TPMT normal metabolizers,the predictive performance of a threshold of 315.72 fmol/μg DNA was much more remarkable with an AUC of 0.902(sensitivity 88%,specificity 85%).6TGN had a relatively poor correlation with late leucopenia whether in the entire sample(P=0.021)or NUDT15/TPMT normal or intermediate metabolizers(P=0.018,P=0.55,respectively).CONCLUSION Proactive therapeutic drug monitoring of DNATG could be an effective strategy to prevent late leucopenia in both NUDT15/TPMT normal and intermediate metabolizers with CD,especially the former.

关键词： Thiopurine-induced late leucopenia DNA-thioguanine 6-thioguanine nucleotide Proactive therapeutic drug monitoring Crohn’s disease

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：