检索结果-南通市图书馆

A Cross-linked Polyethylene with Recyclability and Mechanical Robustness Enabled by Establishment of Multiple Hydrogen Bonds Network via Reactive Melt Blending

引用

Chinese Journal of Polymer Science 2023年第7期41卷 1104-1114页

作者： Hong-Da Mao Ting-Ting Zhang Zhen-You Guo dong-yu bai Jie Wang Hao Xiu Qiang Fu College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu610065China Chongqing University Key Laboratory of Micro/Nano Materials Engineering and Technology Chongqing University of Arts and SciencesChongqing402160China Hubei Huifu Nanomaterial Co. LTD.Yichang443007China

Physical cross-linking by hydrogen-bonds (H-bonds), providing a good combination of application properties of thermosets and processability of thermoplastics, is a potential strategy to resolve the recycling problem of traditional chemically cross-linked polyethylene. However, ureidopyrimidone (UPy), the most widely used H-bonding motif, is unfavorable for large-scale industrial application due to its poor thermal stability. In this work, H-bonds cross-linked polyethylene was successfully prepared by reactive melt blending maleic anhydride grafted polyethylene (PE-g-MAH) with 3-amino-1,2,4-triazole (ATA) to form amide triazole ring-carboxylic acid units. Triazole ring can easily generate multiple H-bonds with carboxylic acid and amide. More importantly, these units are more thermal stable than UPy due to the absence of unstable urea group of UPy. The introduction of H-bonds cross-linking leads to an obvious improvement in mechanical properties and creep resistance and a good maintain in thermal properties and recyclability. Furthermore, the reinforcement effect monotonically improves with increasing the density of H-bonds. The obtained good properties are mainly attributed to largely enhanced interchain interactions induced by H-bonds cross-linking and intrinsic reversibility of H-bonds. This work develops a novel way for the simple fabrication of H-bonds cross-linked PE with high performance through reactive melt blending.

关键词： Cross-linked polyethylene Hydrogen bonds Recyclability

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

Identity-based searchable attribute signcryption in lattice for a blockchain-based medical system

引用

Frontiers of Information Technology & Electronic Engineering 2024年第3期25卷 461-471页

作者： Huifang yu Xiaoping bai School of Cyberspace Security Xi'an University of Posts&TelecommunicationsXi'an 710121China School of Information Engineering Qinghai Communications Technical CollegeXining 810003China

Electronic healthcare systems can offer convenience but face the risk of data forgery and information leakage.To solve these issues,we propose an identity-based searchable attribute signcryption in lattice for a blockchain-based medical system(BCMS-LIDSASC).BCMS-LIDSASC achieves decentralization and anti-quantum security in the blockchain environment,and provides fine-grained access control and searchability.Furthermore,smart contracts are used to replace traditional trusted third parties,and the interplanetary file system(IPFS)is used for ciphertext storage to alleviate storage pressure on the blockchain.Compared to other schemes,BCMS-LIDSASC requires smaller key size and less storage,and has lower computation cost.It contributes to secure and efficient management of medical data and can protect patient privacy and ensure the integrity of electronic healthcare systems.

关键词： Blockchain Identity-based searchable attribute signcryption Distributed storage NTRU lattice

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

Risk evaluation for the task transfer of an aircraft maintenance program based on a multielement connection number

引用

Frontiers of Engineering Management 2024年第1期11卷 16-31页

作者： Tao LIU Zhibo SHI Huifen dong Jie bai yu YAN College of Electronics Information and Automation Civil Aviation University of ChinaTianjin 300300China College of Airworthiness Civil Aviation University of ChinaTianjin 300300China

This paper proposes a framework for evaluating the efficacy and suitability of maintenance programs with a focus on quantitative risk assessment in the domain of aircraft maintenance task transfer. The analysis is anchored in the principles of Maintenance Steering Group-3 (MSG-3) logic decision paradigms. The paper advances a holistic risk assessment index architecture tailored for the task transfer of maintenance programs. Utilizing the analytic network process (ANP), the study quantifies the weight interrelationships among diverse variables, incorporating expert-elicited subjective weighting. A multielement connection number-based evaluative model is employed to characterize decision-specific data, thereby facilitating the quantification of task transfer-associated risk through the appraisal of set-pair potentials. Moreover, the paper conducts a temporal risk trend analysis founded on partial connection numbers of varying orders. This analytical construct serves to streamline the process of risk assessment pertinent to maintenance program task transfer. The empirical component of this research, exemplified through a case study of the Boeing 737NG aircraft maintenance program, corroborates the methodological robustness and pragmatic applicability of the proposed framework in the quantification and analysis of mission transfer risk.

关键词： risk evaluation maintenance steering group analytic network process task transfer maintenance program

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

No Incidence of Liver Cancer Was Observed in A Retrospective Studyof Patients with Aristolochic Acid Nephropathy

引用

Chinese Journal of Integrative Medicine 2024年第2期30卷 99-106页

作者： SU Tao FANG Zhi-e GUO yu-ming WANG Chun-yu WANG Jia-bo JI dong bai Zhao-fang YANG Li XiAO Xiao-he Renal Division Department of MedicinePeking University First HospitalBeijing(100034)China Department of Pharmacy Chongqing Hospital of Traditional Chinese MedicineChongqing(400021)China Department of Hepatology Fifth Medical Center of Chinese PLA General HospitalBeijing(100039)China China Military Institute of Chinese Materia Fifth Medical Center of Chinese PLA General HospitalBeijing(100039)China Phase I Clinical Trials Unit Department of Medicine for Infectious DiseasesFifth Medical Center of Chinese PLA General HospitalBeijing(100039)China Department of Pharmacy Affiliated Hospital of Shandong University of Traditional Chinese MedicineJinan(250000)China National Key Laboratory of Kidney Diseases Beijing(100039)China

Objective:To assess the risk of aristolochic acid(AA)-associated cancer in patients with AA nephropathy(AAN).Methods:A retrospective study was conducted on patients diagnosed with AAN at Peking University First Hospital from January 1997 to December 2014.Long-term surveillance and follow-up data were analyzed to investigate the influence of different factors on the prevalence of cancer.The primary endpoint was the incidence of liver cancer,and the secondary endpoint was the incidence of urinary cancer during 1 year after taking AA-containing medication to 2014.Results:A total of 337 patients diagnosed with AAN were included in this study.From the initiation of taking AA to the termination of follow-up,39 patients were diagnosed with cancer.No cases of liver cancer were observed throughout the entire follow-up period,with urinary cancer being the predominant type(34/39,87.17%).Logistic regression analysis showed that age,follow-up period,and diabetes were potential risk factors,however,the dosage of the drug was not significantly associated with urinary cancer.Conclusions:No cases of liver cancer were observed at the end of follow-up.However,a high prevalence of urinary cancer was observed in AAN patients.Establishing a direct causality between AA and HCC is challenging.

关键词： aristolochic acid hepatocellular carcinoma urinary cancer drug safety retrospective study

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

Design and mechanical properties analysis of a cellular Waterbomb origamistructure

引用

Theoretical & Applied Mechanics Letters 2024年第3期14卷 193-202页

作者： Yongtao bai Zhaoyu Wang yu Shi School of Civil Engineering Chongqing UniversityChongqing 400045China Research Center of Steel Structure Engineering Chongqing UniversityChongqing 400045China

Cellular structures are commonly used to design energy-absorbing structures,and origami structures are becominga prevalent method of cellular structure design.This paper proposes a foldable cellular structure based on theWaterbomb origami pattern.The geometrical configuration of this structure is described.Quasi-static compressiontests of the origami tube cell of this cellular structure are conducted,and load-displacement relationship curvesare obtained.Numerical simulations are carried out to analyze the effects of aspect ratio,folding angle,thicknessand number of layers of origami tubes on initial peak force and specific energy absorption(SEA).Calculationformulas for initial peak force and SEA are obtained by the multiple linear regression method.The degree ofinfluence of each parameter on the mechanical properties of the single-layer tube cell is compared.The resultsshow that the cellular structure exhibits negative stiffness and periodic load-bearing capacity,as well as foldingangle has the most significant effect on the load-bearing and energy-absorbing capacity.By adjusting the designparameters,the stiffness,load-bearing capacity and energy absorption capacity of this cellular structure can beadjusted,which shows the programmable mechanical properties of this cellular structure.The foldability andthe smooth periodic load-bearing capacity give the structure potential for application as an energy-absorbingstructure.

关键词： Cellular structure Waterbomb origami Mechanical metamaterial Numerical simulation Energy absorption

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

Grassland-type ecosystem stability in China differs under the influence of drought and wet events

引用

Journal of Arid Land 2024年第5期16卷 615-631页

作者： CAO Wenyu bai Jianjun yu Leshan School of Geography and Tourism Shaanxi Normal UniversityXi'an 710119China International Business School Shaanxi Normal UniversityXi'an 710119China

Ecological stability is a core issue in ecological research and holds significant implications forhumanity. The increased frequency and intensity of drought and wet climate events resulting from climatechange pose a major threat to global ecological stability. Variations in stability among different ecosystemshave been confirmed, but it remains unclear whether there are differences in stability within the sameterrestrial vegetation ecosystem under the influence of climate events in different directions and intensities.China's grassland ecosystem includes most grassland types and is a good choice for studying this issue.This study used the Standardized Precipitation Evapotranspiration Index-12 (SPEI-12) to identify thedirections and intensities of different types of climate events, and based on Normalized DifferenceVegetation Index (NDVI), calculated the resistance and resilience of different grassland types for 30consecutive years from 1990 to 2019 (resistance and resilience are important indicators to measurestability). Based on a traditional regression model, standardized methods were integrated to analyze theimpacts of the intensity and duration of drought and wet events on vegetation stability. The resultsshowed that meadow steppe exhibited the highest stability, while alpine steppe and desert steppe had thelowest overall stability. The stability of typical steppe, alpine meadow, temperate meadow was at anintermediate level. Regarding the impact of the duration and intensity of climate events on vegetationecosystem stability for the same grassland type, the resilience of desert steppe during drought was mainlyaffected by the duration. In contrast, the impact of intensity was not significant. However, alpine steppewas mainly affected by intensity in wet environments, and duration had no significant impact. Ourconclusions can provide decision support for the future grassland ecosystem governance.

关键词： grassland ecosystem stability resistance resilience different climate types drought climate event wet climate event

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

Compound extreme inundation risk of coastal wetlands caused by climate change and anthropogenic activities in the Yellow River Delta,China

引用

Advances in Climate Change Research 2024年第1期15卷 134-147页

作者： Xiao-Li WANG Ai-Qing FENG Xi-Yong HOU Qing-Chen CHAO bai-yuan SONG yu-Bin LIU Qi-Guang WANG He XU yu-Xin ZHANG dong Li Li-Jie dong yu GUO CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation Yantai Institute of Coastal Zone ResearchChinese Academy of SciencesYantai 264003China Shandong Key Laboratory of Coastal Environmental Processes Yantai 264003China China Meteorological Administration Key Laboratory for Climate Prediction Studies National Climate CentreBeijing 100081China Tongji Urban Planning Design Research Institute Shanghai 200092China School of Geography and Tourism Qilu Normal UniversityJinan 250200China China Meteorological Administration Training Centre China Meteorological AdministrationBeijing 10008China University of Chinese Academy of Sciences Beijing 100049China Marine Science and Technology College Zhejiang Ocean UniversityZhoushan 316022China

The coastal wetlands of the Yellow River Delta(YRD)in China are crucial for their valuable resources,environmental significance,and economic contributions.However,these wetlands are also vulnerable to the dual threats of climate change and human disturbances.Despite substantial attention to the historical shifts in YRD's coastal wetlands,uncertainties remain regarding their future trajectory in the face of compound risks from climate change and anthropogenic activities.Based on a range of remote sensing data sources,this study undertakes a comprehensive investigation into the evolution of YRD's coastal wetlands between 2000 and 2020.Subsequently,the potential fate of coastal wetlands is thoroughly analyzed through the Land Use/Cover Change(LUCC)simulation using System Dynamic-Future Land Use Simulation(SD-FLUS)model and the extreme water levels projection integrated future sea-level rise,storm surge,and astronomical high tide in 2030,2050,and 2100 under scenarios of SSP1-2.6,SSP2-4.5,and SSP5-8.5.Results revealed that YRD's coastal wetlands underwent a marked reduction,shrinking by 1688.72 km²from 2000 to 2020.This decline was mostly attributed to the substantial expansion in the areas of artificial wetlands(increasing by 823.78 km2),construction land(increasing by 767.71 km²),and shallow water(increasing by 274.58 km²).Looking ahead to 2030-2100,the fate of coastal wetlands appears to diverge based on different scenarios.Under the SSP1-2.6 scenario,the area of coastal wetland is projected to experience considerable growth.In contrast,the SSP5-8.5 scenario anticipates a notable decrease in coastal wetlands.Relative to the inundated area suffered from the current extreme water levels,the study projects a decrease of 6.8%-10.6%in submerged coastal wetlands by 2030 and 9.4%-18.2%by 2050 across all scenarios.In 2100,these percentages are projected to decrease by 0.4%(SSP2-4.5)and 27.1%(SSP5-8.5),but increase by 35.7%(SSP1-2.6).Results suggest that coastal wetlands in the YRD will face a serious compound risk from cli

关键词： Climate change Anthropogenic activities Compound extreme risk Coastal wetlands Yellow River Delta

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

Reliable calculations of nuclear binding energies by the Gaussian process of machine learning

引用

Nuclear Science and Techniques 2024年第6期35卷 130-144页

作者： Zi-Yi yuan dong bai Zhen Wang Zhong-Zhou Ren School of Physics Science and Engineering Tongji UniversityShanghai 200092China College of Science Hohai UniversityNanjing 211100China Key Laboratory of Advanced Micro-Structure Materials Ministry of EducationShanghai 200092China

Reliable calculations of nuclear binding energies are crucial for advancing the research of nuclear physics.Machine learning provides an innovative approach to exploring complex physical problems.In this study,the nuclear binding energies are modeled directly using a machine-learning method called the Gaussian process.First,the binding energies for 2238 nuclei with Z>20 and N>20 are calculated using the Gaussian process in a physically motivated feature space,yielding an average deviation of 0.046 MeV and a standard deviation of 0.066 MeV.The results show the good learning ability of the Gaussian process in the studies of binding energies.Then,the predictive power of the Gaussian process is studied by calculating the binding energies for 108 nuclei newly included in AME2020.The theoretical results are in good agreement with the experimental data,reflecting the good predictive power of the Gaussian process.Moreover,the-decay energies for 1169 nuclei with 50≤Z≤110 are derived from the theoretical binding energies calculated using the Gaussian process.The average deviation and the standard deviation are,respectively,0.047 MeV and 0.070 MeV.Noticeably,the calculated-decay energies for the two new isotopes 204 Ac(Huang et al.Phys Lett B 834,137484(2022))and 207 Th(Yang et al.Phys Rev C 105,L051302(2022))agree well with the latest experimental data.These results demonstrate that the Gaussian pro-cess is reliable for the calculations of nuclear binding energies.Finally,the-decay properties of some unknown actinide nuclei are predicted using the Gaussian process.The predicted results can be useful guides for future research on binding energies and-decay properties.

关键词： Nuclear binding energies decay Machine learning Gaussian process

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

Unraveling magnetic properties and martensitic transformation in Mn-rich Ni-Mn-Sn alloys:first-principles calculations and experiments

引用

Rare Metals 2024年第4期43卷 1769-1785页

作者： yu Zhang Jing bai Ke-Liang Guo Jia-Xin Xu Jiang-Long Gu Nicola Morley Qui-Zhi Gao yu-dong Zhang Claude Esling Xiang Zhao Liang Zuo Key Laboratory for Anisotropy and Texture of Materials (Ministry of Education) School of Material Science and EngineeringNortheastern University Key Laboratory of Dielectric and Electrolyte Functional Material Hebei Province School of Resources and Materials Northeastern University at Qinhuangdao Department of Material Science and Engineering University of Sheffield State Key Laboratory of Metastable Materials Science and Technology Yanshan University Laboratoire d'Etude des Microstructures Et de Mecanique des Materiaux University of Lorraine

We have investigated the phase stability,magnetic properties,and martensitic transformation thermodynamics/kinetics of the Ni24-xMn18+x+ySn6-y（x,y=0,1,2） system by combining the first-principles calculations and experiments.The calculation results show that the optimized lattice parameters are consistent with the experimental data.Respectively,we obtain the relation equation for the austenite formation energy(Eform-A) and Mn content(XMn):Eform-A=507.358XMn-274.126,as well as for the six-layer modulated（6M） martensite formation energy(Eform-6M) and Ni content(XNi):Eform-6M=-728.484XNi+264.374.The ternary phase diagram of the total magnetic moment was established.The excess Mn will reduce the total magnetic moment of 6M（Mag6M） and non-modulated（NM）(MagNM) martensites,with the following equations relating the total magnetic moment and Mn content:Mag6M=-15.905XMn+7.902and MagNM=-14.781XMn+7.411,while the effect on austenite is complex.The variation of total magnetic moment is mainly dominated by the Mn atomic magnetic moment.The 3d electrons of MnSn（Mn at Sn sublattice）play an important role in magnetic properties from the perspective of the electronic density of states.Based on the thermodynamics of martensitic transformation,the alloys will likely undergo austenite?6M?NM transformation sequence.Combining the thermodynamic and kinetic results,the martensitic transformation temperature decreases with x increasing and increases with y increasing.These results are expected to provide reference for predicting the phase stability and magnetic properties of NiMn-Sn alloys.

关键词： Ni–Mn–Sn First-principles calculations Martensitic transformation Magnetic property Kinetics

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Mesenchymal stem cells for repairing glaucomatous optic nerve

引用

International Journal of Ophthalmology(English edition) 2024年第4期17卷 748-760页

作者： bai-yu Hu Mei Xin Ming Chen Ping yu Liu-Zhi Zeng Eye School of Chengdu University of TCM Chengdu 610000Sichuan ProvinceChina Department of Ophthalmology Chengdu First People’s HospitalChengdu 610095Sichuan ProvinceChina

Glaucoma is a common and complex neurodegenerative disease characterized by progressive loss of retinal ganglion cells(RGCs)and axons.Currently,there is no effective method to address the cause of RGCs degeneration.However,studies on neuroprotective strategies for optic neuropathy have increased in recent years.Cell replacement and neuroprotection are major strategies for treating glaucoma and optic neuropathy.Regenerative medicine research into the repair of optic nerve damage using stem cells has Received considerable attention.Stem cells possess the potential for multidirectional differentiation abilities and are capable of producing RGCfriendly microenvironments through paracrine effects.This article reviews a thorough researches of recent advances and approaches in stem cell repair of optic nerve injury,raising the controversies and unresolved issues surrounding the future of stem cells.

关键词： stem cell glaucoma retinal ganglion cell optic nerve axon regeneration

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：