检索结果-南通市图书馆

COF-based membranes for liquid phase separation:Preparation,mechanism and perspective

Journal of Environmental Sciences 2024年第7期141卷 63-89页

作者： Yujie Zhao he Gu Yilun Zhou caimeiWen Xiaolu Liu Suhua Wang Zhongshan Chen Hui Yang Xiangke Wang College of Environmental Science and Engineering North China Electric Power UniversityBeijing 102206China School of Environmental Science and Engineering Guangdong University of Petrochemical TechnologyMaoming 525000China

Covalent organic frameworks(COFs)are a new kind of crystalline porous materials composed of organic molecules connected by covalent bonds,processes the characteristics of low density,large specific surface area,adjustable pore size and structure,and easy to functionalize,which have been widely used in the field of membrane separation technology.Recently,there are more and more researches focusing on the preparation methods,separation application,and mechanism of COF membranes,which need to be further summarized and compared.In this review,we primarily summarized several conventional preparation methods,such as two-phase interfacial polymerization,in-situ growth on substrate,unidirectional diffusion method,layer-by-layer assembly method,mixed matrix membranes,and so on.The advantages and disadvantages of each method are briefly summarized.The application potential of COF membrane in liquid separation are introduced from four aspects:dyeing wastewater treatment,heavy metal removal,seawater desalination and oil-water separation.Then,the mechanisms including pore structure,hydrophilic/hydrophobic,electrostatic repulsion/attraction and Donnan effect are introduced.For the efficient removal of different kind of pollutions,researchers can select different ligands to construct membranes with specific pore size,hydrophily,salt or organic rejection ability and functional group.The ideas for the design and preparation of COF membranes are introduced.Finally,the future direction and challenges of the next generation of COF membranes in the field of separation are prospected.

关键词： Covalent organic frameworks Membrane materials Liquid phase separation Separation mechanism

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

Influence of layer thickness on formation quality,microstructure,mechanical properties,and corrosion resistance of WE43 magnesium alloy fabricated by laser powder bed fusion

引用

Journal of Magnesium and Alloys 2024年第4期12卷 1367-1385页

作者： Bangzhao Yin Jinge Liu Bo Peng Mengran Zhou Bingchuan Liu Xiaolin Ma caimei Wang Peng Wen Yun Tian Yufeng Zheng State Key Laboratory of Tribology in Advanced Equipment Beijing100084China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China Institute for Precision Medicine Tsinghua UniversityBeijing102218China Department of Orthopaedics Peking University Third HospitalBeijing 100191China Beijing AKEC Medical Co. Ltd.Beijing 102200China School of Materials Science and Engineering Peking UniversityBeijing 100871China Engineering Research Center of Bone and Joint Precision Medicine Ministry of EducationBeijing 100191China

Laser powder bed fusion(L-PBF)of Mg alloys has provided tremendous opportunities for customized production of aeronautical and medical parts.Layer thickness(LT)is of great significance to the L-PBF process but has not been studied for Mg alloys.In this study,WE43 Mg alloy bulk cubes,porous scaffolds,and thin walls with layer thicknesses of 10,20,30,and 40μm were fabricated.The required laser energy input increased with increasing layer thickness and was different for the bulk cubes and porous scaffolds.Porosity tended to occur at the connection joints in porous scaffolds for LT40 and could be eliminated by reducing the laser energy input.For thin wall parts,a large overhang angle or a small wall thickness resulted in porosity when a large layer thicknesses was used,and the porosity disappeared by reducing the layer thickness or laser energy input.A deeper keyhole penetration was found in all occasions with porosity,explaining the influence of layer thickness,geometrical structure,and laser energy input on the porosity.All the samples achieved a high fusion quality with a relative density of over 99.5%using the optimized laser energy input.The increased layer thickness resulted to more precipitation phases,finer grain sizes and decreased grain texture.With the similar high fusion quality,the tensile strength and elongation of bulk samples were significantly improved from 257 MPa and 1.41%with the 10μm layer to 287 MPa and 15.12%with the 40μm layer,in accordance with the microstructural change.The effect of layer thickness on the compressive properties of porous scaffolds was limited.However,the corrosion rate of bulk samples accelerated with increasing the layer thickness,mainly attributed to the increased number of precipitation phases.

关键词： Magnesium alloy WE43 Laser powder bed fusion Layer thickness Process optimization

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

Improving corrosion resistance of additively manufactured WE43 magnesium alloy by high temperature oxidation for biodegradable applications

引用

Journal of Magnesium and Alloys 2024年第3期12卷 940-953页

作者： Jinge Liu Bangzhao Yin Fei Song Bingchuan Liu Bo Peng Peng Wen Yun Tian Yufeng Zheng Xiaolin Ma caimei Wang State Key Laboratory of Tribology in Advanced Equipment Beijing100084China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China Department of Orthopaedics Beijing Tsinghua Changgung HospitalInstitute for Precision MedicineTsinghua UniversityBeijing102218China Department of Orthopaedics Peking University Third HospitalBeijing 100191China Engineering Research Center of Bone and Joint Precision Medicine Ministry of EducationBeijing 100191China School of Materials Science and Engineering Peking UniversityBeijing 100871China Beijing AKEC Medical Co. Ltd.Beijing 102200China

Laser powder bed fusion(L-PBF)has been employed to additively manufacture WE43 magnesium(Mg)alloy biodegradable implants,but WE43 L-PBF samples exhibit excessively rapid corrosion.In this work,dense WE43 L-PBF samples were built with the relativity density reaching 99.9%.High temperature oxidation was performed on the L-PBF samples in circulating air via various heating temperatures and holding durations.The oxidation and diffusion at the elevated temperature generated a gradient structure composed of an oxide layer at the surface,a transition layer in the middle and the matrix.The oxide layer consisted of rare earth(RE)oxides,and became dense and thick with increasing the holding duration.The matrix was composed ofα-Mg,RE oxides and Mg_(24)RE_(5) precipitates.The precipitates almost disappeared in the transition layer.Enhanced passivation effect was observed in the samples treated by a suitable high temperature oxidation.The original L-PBF samples lost 40%weight after 3-day immersion in Hank’s solution,and broke into fragments after 7-day immersion.The casted and solution treated samples lost roughly half of the weight after 28-day immersion.The high temperature oxidation samples,which were heated at 525℃ for 8 h,kept the structural integrity,and lost only 6.88%weight after 28-day immersion.The substantially improved corrosion resistance was contributed to the gradient structure at the surface.On one hand,the outmost dense layer of RE oxides isolated the corrosive medium;on the other hand,the transition layer considerably inhibited the corrosion owing to the lack of precipitates.Overall,high temperature oxidation provides an efficient,economic and safe approach to inhibit the corrosion of WE43 L-PBF samples,and has promising prospects for future clinical applications.

关键词： Laser powder bed fusion Biodegradable magnesium alloy High temperature oxidation Corrosion resistance WE43.

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

A 3D-printed microhemispherical shell resonator with electrostatic tuning for a Coriolis vibratory gyroscope

引用

Microsystems & Nanoengineering 2024年第2期10卷 25-35页

作者： Baoyin Hou Ye Zhu Chaofan he Weidong Wang Zhi Ding Wen he Yong he Lufeng Che College of Information Science and Electronic Engineering Zhejiang UniversityHangzhou310027China Center for Microelectronics Shaoxing InstituteZhejiang UniversityShaoxing312035China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou310058China School of Mechanical Engineering Zhejiang UniversityHangzhou310058China

The emergence of microhemispherical resonant gyroscopes,which integrate the advantages of exceptional stability and long lifetime with miniaturization,has afforded new possibilities for the development of whole-angle gyroscopes.However,existing methods used for manufacturing microhemispherical resonant gyroscopes based on MEMS technology face the primary drawback of intricate and costly processing.here,we report the design,fabrication,and characterization of the first 3D-printable microhemispherical shell resonator for a Coriolis vibrating gyroscope.We remarkably achieve fabrication in just two steps bypassing the dozen or so steps required in traditional micromachining.By utilizing the intricate shaping capability and ultrahigh precision offered by projection microstereolithography,we fabricate 3D high-aspect-ratio resonant structures and controllable capacitive air gaps,both of which are extremely difficult to obtain via MEMS technology.In addition,the resonance frequency of the fabricated resonators can be tuned by electrostatic forces,and the fabricated resonators exhibit a higher quality factor in air than do typical MEMS microhemispherical resonators.This work demonstrates the feasibility of rapidly batch-manufacturing microhemispherical shell resonators,paving the way for the development of microhemispherical resonator gyroscopes for portable inertial navigation.Moreover,this particular design concept could be further applied to increase uptake of resonator tools in the MEMS community.

关键词： resonator tuning electrostatic

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

Circulating tumor cells shielded with extracellular vesicle-derived CD45 evade T cell attack to enable metastasis

引用

Signal Transduction and Targeted Therapy 2024年第5期9卷 2114-2131页

作者： Chuan Yang Xueping Wang Kenneth K.W.To caimei Cui Min Luo Shaocong Wu Lamei Huang Kai Fu Can Pan Zeyu Liu Teng Fan Caibo Yang Fang Wang Liwu Fu State Key Laboratory of Oncology in South China Guangdong Provincial Clinical Research Center for CancerSun Yat-sen University Cancer CenterGuangzhou 510060P.R.China School of Pharmacy Faculty of MedicineThe Chinese University of Hong KongHong KongChina LABVIV Technology(Shenzhen)Co. LtdShenzhen 518057China

Circulating tumor cells(CTCs)are precursors of distant metastasis in a subset of cancer patients.A better understanding of CTCs heterogeneity and how these CTCs survive during hematogenous dissemination could lay the foundation for therapeutic prevention of cancer metastasis.It remains elusive how CTCs evade immune surveillance and elimination by immune cells.In this study,we unequivocally identified a subpopulation of CTCs shielded with extracellular vesicle(EVs)-derived CD45(termed as CD45^(+)CTCs)that resisted T cell attack.A higher percentage of CD45^(+)CTCs was found to be closely correlated with higher incidence of metastasis and worse prognosis in cancer patients.Moreover,CD45^(+)tumor cells orchestrated an immunosuppressive milieu and CD45^(+)CTCs exhibited remarkably stronger metastatic potential than CD45−CTCs in vivo.Mechanistically,CD45 expressing on tumor surfaces was shown to form intercellular CD45-CD45 homophilic interactions with CD45 on T cells,thereby preventing CD45 exclusion from TCR-pMHC synapse and leading to diminished TCR signaling transduction and suppressed immune response.Together,these results pointed to an underappreciated capability of EVs-derived CD45-dressed CTCs in immune evasion and metastasis,providing a rationale for targeting EVs-derived CD45 internalization by CTCs to prevent cancer metastasis.

关键词： CD45 metastasis prevention

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

Chemotherapy induces breast cancer stem cell enrichment through repression of glutathione S-transferase Mu

引用

Genes & Diseases 2024年第2期11卷 528-531页

作者： Jing he Yiran Yu Yilin he Jie he Guangyu Ji Haiquan Lu The Second Hospital and Advanced Medical Research Institute Cheeloo College of MedicineShandong UniversityJinanShandong 250012China Department of Nursing The First Affiliated Hospital of Shandong First Medical UniversityJinanShandong 250014China School of Medicine Xinjiang Medical UniversityUrumqiXinjiang 830054China School of Medicine Binzhou Medical UniversityYantaiShandong 264003China Oncology Department Jinan Zhangqiu District People's HospitalJinanShandong 250200China Key Laboratory for Experimental Teratology of the Ministry of Education Cheeloo College of MedicineShandong UniversityJinanShandong 250012China Center for Reproductive Medicine Shandong UniversityJinanShandong 250012China

Triple-negative breast cancer(TNBC)has aggressive characteristics as exemplified by the high risk of recurrence,metastasis,and patient mortality.1 Cytotoxic chemotherapy may reduce tumor burden initially,but leave behind chemo-resistant breast cancer stem cells(BCSCs)that lead to tumor recurrence and metastasis.2 Chemotherapy induces BCsC enrichment through the activation of glutathione biosynthesis pathways,which increases intracellular glutathione levels and specifies the BCSC phenotype through complicated downstream signaling pathways.3 Glutathione S-transferases(GSTs),a superfamily(which contains seven cytosolic classes:Alpha,Kappa,Mu,Omega,Pi,Theta,and Zeta,and one microsomal class MGSTs)of phase Il enzymes that catalyze the conjugation of glutathione with electrophilic compounds,play a critical role in detoxification and chemotherapy resistance of cancer cells.However,the role of GSTs in the regulation of BCSCs is largely elusive.

关键词： chemotherapy breast metastasis

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

Coupled Numerical Simulation of Electromagnetic and Flow Fields in a Magnetohydrodynamic Induction Pump

引用

Fluid Dynamics & Materials Processing 2024年第4期20卷 889-899页

作者： he Wang Ying he College of Transportation Ludong UniversityYantai264025China College of Intelligent Manufacturing City College of HuizhouHuizhou516025China

Magnetohydrodynamic(MHD)induction pumps are contactless pumps able to withstand harsh environments.The rate of fluid flow through the pump directly affects the efficiency and stability of the device.To explore the influence of induction pump settings on the related delivery speed,in this study,a numerical model for coupled electromagnetic and flow field effects is introduced and used to simulate liquid metal lithium flow in the induction pump.The effects of current intensity,frequency,coil turns and coil winding size on the velocity of the working fluid are analyzed.It is shown that the first three parameters have a significant impact,while changes in the coil turns have a negligible influence.The maximum increase in working fluid velocity within the pump for the parameter combination investigated in this paper is approximately 618%.As the frequency is increased from 20 to 60 Hz,the maximum increase in the mean flow rate of the working fluid is approximately 241%.These research findings are intended to support the design and optimization of these devices.

关键词： Magnetic fluid multi-physical field coupling induction pump numerical simulation liquid metal conveying

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

Honeycomb-like biochar framework coupled with Fe_(3)O_(4)/FeS nanoparticles as efficient heterogeneous Fenton catalyst for phenol degradation

引用

Journal of Environmental Sciences 2024年第2期136卷 390-399页

作者： Aihua Cheng Yi he Xiaohe Liu Chi he Department of Environmental Engineering College of Geology and EnvironmentXi’an University of Science and TechnologyXi’an 710054China State Key Laboratory of Multiphase Flow in Power Engineering School of Energy and Power EngineeringXi’an Jiaotong UniversityXi’an 710049China National Engineering Laboratory for VOCs Pollution Control Material and Technology University of Chinese Academy of SciencesBeijing 101408China

Achieving an efficient and stable heterogeneous Fenton reaction over a wide pH range is of great significance for wastewater treatment.here,a pollen-derived biochar catalyst with a unique honeycomb-like structure,coupled with the dispersion of magnetic Fe_(3)O_(4)/FeS(Fe/S)nanoparticles,was synthesized by simple impregnation precursor,followed by pyrolysis.The prepared Fe/S-biochar catalyst demonstrated outstanding phenol degradation efficiency across a wide pH range,with 98%of which eliminated even under neutral conditions(pH 7.0).The high catalytic activity was due to the multilevel porous structure of pollenderived biochar provided enough active sites and allowed for better electron transfer,then increases oxidation ability to promote the reaction.Moreover,the acid microenvironment formed by SO_(4)^(2-)group from Fe/S composite extended the pH range for Fenton reaction,and S^(2-)facilitated the conversion of≡Fe^(3+)to≡Fe^(2+),resulting in remarkable degradation efficiency.Further,biochar can effectively promote cycling stability by limiting Fe leaching.This work may provide a general strategy for designing 3D framework biochar-based Fe/S catalysts with excellent performance for heterogeneous Fenton reactions.

关键词： Biomass Biochar Fenton reaction Fe_(3)O_(4)/FeS(Fe/S) Phenol degradation

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

Regulation of insect behavior by non-coding RNAs

引用

Science China(Life Sciences) 2024年第6期67卷 1106-1118页

作者： Jing he Le Kang State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesBeijing 100101China Beijing Institutes of Life Sciences Chinese Academy of SciencesBeijing 100101China College of Life Science Hebei UniversityBaoding 071002China

The adaptation of insects to environments relies on a sophisticated set of behaviors controlled by molecular and physiological processes.Over the past several decades,accumulating studies have unveiled the roles of non-coding RNAs(nc RNAs)in regulating insect behaviors.nc RNAs assume particularly pivotal roles in the behavioral plasticity of insects by rapidly responding to environmental stimuli.nc RNAs also contribute to the maintenance of homeostasis of insects by fine-tuning the expression of target genes.However,a comprehensive review of nc RNAs'roles in regulating insect behaviors has yet to be conducted.here,we present the recent progress in our understanding of how nc RNAs regulate various insect behaviors,including flight and movement,social behavior,reproduction,learning and memory,and feeding.We refine the intricate mechanisms by which nc RNAs modulate the function of neural,motor,reproductive,and other physiological systems,as well as gene expression in insects like fruit flies,social insects,locusts,and mosquitos.Furthermore,we discuss potential avenues for future studies in nc RNA-mediated insect behaviors.

关键词： ncRNAs insect behavior plasticity fine-tuning environmental adaptation

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

Distributed Nash Equilibrium Seeking on Compact Action Sets over Jointly Strongly Connected Switching Networks

引用

Journal of Systems Science & Complexity 2024年第1期37卷 63-81页

作者： he Xiongnan HUANG Jie Department of Mechanical and Automation Engineering The Chinese University of Hong KongHong Kong 999077China.

This paper studies the distributed Nash equilibrium seeking(DNES)problem for games whose action sets are compact and whose network graph is switching satisfying the jointly strongly connected condition.To keep the actions of all players in their action sets all the time,one has to resort to the projected gradient-based method.Under the assumption that the unique Nash equilibrium is the unique equilibrium of the pseudogradient system,an algorithm is proposed that is able to exponentially find the Nash equilibrium.Further,the authors also consider the distributed Nash equilibrium seeking problem for games whose actions are governed by high-order integrator dynamics and belong to some compact sets.Two examples are used to illustrate the proposed approach.

关键词： Compact action sets jointly strongly connected switching graphs Nash equilibrium seeking projected gradient-based algorithm.

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

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：