检索结果-南通市图书馆

Effect of a negative DC bias on a capacitively coupled Ar plasma operated at different radiofrequency voltages and gas pressures

引用

Plasma Science and Technology 2024年第5期26卷 62-71页

作者：相垚君王晓坤刘永新王友年 Key Laboratory of Materials Modification by Laser Ionand Electron Beams(Ministry of Education)School of PhysicsDalian University of TechnologyDalian 116024People’s Republic of China Chair of Applied Electrodynamics and Plasma Technology Ruhr University BochumBochum 44801Germany

The effect of a negative DC bias,|V_(dc)|,on the electrical parameters and discharge mode is investigated experimentally in a radiofrequency(RF)capacitively coupled Ar plasma operated at different RF voltage amplitudes and gas *** electron density is measured using a hairpin probe and the spatio-temporal distribution of the electron-impact excitation rate is determined by phase-resolved optical emission *** electrical parameters are obtained based on the waveforms of the electrode voltage and plasma current measured by a voltage probe and a current *** was found that at a low|V_(dc)|,***α-mode,the electron density and RF current decline with increasing|V_(dc)|;meanwhile,the plasma impedance becomes more capacitive due to a widened ***,RF power deposition is ***|V_(dc)|exceeds a certain value,the plasma changes toα–γhybrid mode(or the discharge becomes dominated by theγ-mode),manifesting a drastically growing electron density and a moderately increasing RF ***,the plasma impedance becomes more resistive,so RF power deposition is enhanced with|V_(dc)|.We also found that the electrical parameters show similar dependence on|V_(dc)|at different RF voltages,andα–γmode transition occurs at a lower|V_(dc)|at a higher RF *** increasing the pressure,plasma impedance becomes more resistive,so RF power deposition and electron density are *** particular,theα–γmode transition tends to occur at a lower|V_(dc)|with increase in pressure.

关键词： RF capacitively coupled plasma DC-overlapped RF discharge power deposition discharge mode transition

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

Mechanical regulation of lipid and sugar absorption by Piezo1 in enterocytes

引用

Acta Pharmaceutica Sinica B 2024年第8期14卷 3576-3590页

作者： Tian Tao Qing Shu Yawen Zhao Wenying Guo Jinting Wang Yuhao Shi Shiqi Jia Hening Zhai Hui Chen Cunchuan Wang Geyang Xu Department of Physiology School of MedicineJinan UniversityGuangzhou 510632China Department of Metabolic and Bariatric Surgery the First Affiliated Hospital of Jinan UniversityGuangzhou 510630China Endoscopy Center the First Affiliated Hospital of Jinan UniversityGuangzhou 510630China Biotherapy Center Cell-gene Therapy Translational Medicine Research Centerthe Third Affiliated HospitalSun Yat-sen UniversityGuangzhou 510630China Key Laboratory of Viral Pathogenesis&Infection Prevention and Control(Jinan University) Ministry of EducationGuangzhou 510632China

Obesity is primarily caused by excessive intake as well as absorption of sugar and *** surge in distention pressure and intestinal motility accelerates the absorption of *** response of intestinal epithelial cells to mechanical stimulation is not fully ***1,a mechanosensitive ion channel,is widely expressed throughout the digestive ***,its function in intestinal nutrient absorption is not yet *** our study,excessive lipid deposition was observed in the duodenum of obese patients,while duodenal Piezo1-CaMKK2-AMPKa was decreased when compared to normal-weight *** high-fat diet condition,the Piezo1iKO mice exhibited abnormally elevated sugar and lipid absorption as well as severe lipid deposition in the duodenum and *** phenotypes were mainly caused by the inhibition of duodenal CaMKK2-AMPKa and the upregulation of SGLT1 and *** contrast,Yoda1,a Piezo1 agonist,was found to reduce intestinal lipid absorption in diet induced obese *** of Piezo1,stretch and Yoda1 inhibited lipid accumulation and the expression of DGAT2 and SGLT1,whereas knockdown of Piezo1 stimulated lipid accumulation and DGAT2 in Caco-2 *** study reveals a previously unexplored mechanical regulation of nutrient absorption in intestinal epithelial cells,which may shed new light on the therapy of obesity.

关键词： Piezo1 DGAT2 SGLT1 Lipid metabolism Obesity Mechanical sensing Intestinal lipid absorption Intestinal glucose absorption

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

Experimental study and correlation development for the two-phase frictional pressure drop of flow boiling in copper foam fin microchannels

引用

Science china(Technological Sciences) 2024年第9期67卷 2758-2776页

作者： FU Kai XU XiangHua LIANG XinGang School of Aerospace Engineering Tsinghua UniversityBeijing 100084China

Flow boiling in microchannels with porous walls has received extensive attention in recent years. Compared with the emphasis on heat transfer, there is a lack of research on the effect of the porous wall structures on the pressure drop characteristics. In this study, systematic experiments are performed to measure the pressure drop of water-vapor two-phase flow in five microchannels with copper foam fins, which consist of nine or six channels and fins of copper foam. The porosities of the foam fins range from0.78 to 0.82 and ratios of fin width to channel width range from 0.5 to 2. The channels are approximately 0.5 or 1 mm in width and 1 mm in height. Both adiabatic and flow boiling experiments are conducted with water at mass fluxes ranging from 66 to 407 kg/(m^(2)s). In the adiabatic experiments, the average quality in channels is between 0.017 and 0.846. In the flow boiling experiments, the outlet quality of channels is between 0.040 and 0.863. Slug flow, churn flow, annular flow, and wispy-annular flow are observed in adiabatic experiments. A two-phase frictional pressure drop correlation based on the Lockhart-Martinelli model is developed for copper foam fin microchannels by introducing the effects of the mass flux, porosity, ratio of fin width to channel width, and heating condition step by step. The mean absolute percentage errors of the new correlation are 7.53% for 325data points under adiabatic conditions and 5.51% for 268 data points under flow boiling conditions, respectively. This work provides insight into the correlations of frictional pressure drop in microchannels with porous walls.

关键词： two-phase flow boiling pressure drop correlation microchannel copper foam porous wall

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

Human CD56+CD39+ dNK cells support fetal survival through controlling trophoblastic cell fate:immune mechanisms of recurrent early pregnancy loss

引用

national Science Review 2024年第6期11卷 129-145页

作者： Wentong Jia Liyang Ma Xin Yu Feiyang Wang Qian Yang Xiaoye Wang Mengjie Fan Yan Gu Ran Meng Jian Wang Yuxia Li Rong Li Xuan Shao Yan-Ling Wang State Key Laboratory of Stem cell and Reproductive Biology Key Laboratory of Organ Regeneration and ReconstructionInstitute of ZoologyChinese Academy of Sciences Beijing Institute for Stem Cell and Regenerative Medicine University of the Chinese Academy of Sciences NHC Key Lab of Reproduction Regulation Shanghai Engineering Research Center of Reproductive Health Drug and Devices Shanghai Institute for Biomedical and Pharmaceutical Technologies national Clinical Center for Obstetrics and Gynecology Peking University Third Hospital Department of Family Planning The Second Hospital of Tianjin Medical University Department of Prenatal Screening Haidian Maternal and Child Health Hospital

Decidual natural killer（dNK） cells are the most abundant immune cells at the maternal-fetal interface during early pregnancy in both mice and humans, and emerging single-cell transcriptomic studies have uncovered various human dNK subsets that are disrupted in patients experiencing recurrent early pregnancy loss（RPL） at early gestational stage, suggesting a connection between abnormal proportions or characteristics of dNK subsets and RPL pathogenesis. However, the functional mechanisms underlying this association remain unclear. Here, we established a mouse model by adoptively transferring human dNK cells into pregnant NOG（NOD/Shi-scid/IL-2Rγnull） mice, where human dNK cells predominantly homed into the uteri of recipients. Using this model, we observed a strong correlation between the properties of human dNK cells and pregnancy outcome. The transfer of dNK cells from RPL patients（dNK-RPL）remarkably worsened early pregnancy loss and impaired placental trophoblast cell differentiation in the recipients. These adverse effects were effectively reversed by transferring CD56+CD39+dNK *** studies revealed that CD56+CD39+dNK subset facilitates early differentiation of mouse trophoblast stem cells（m TSCs） towards both invasive and syncytial pathways through secreting macrophage colony-stimulating factor（M-CSF）. Administration of recombinant M-CSF to NOG mice transferred with dNK-RPL efficiently rescued the exacerbated pregnancy outcomes and fetal/placental development. Collectively, this study established a novel humanized mouse model featuring functional human dNK cells homing into the uteri of recipients and uncovered the pivotal role of M-CSF in fetal-supporting function of CD56+CD39+dNK cells during early pregnancy, highlighting that M-CSF may be a previously unappreciated therapeutic target for intervening RPL.

关键词： recurrent pregnancy loss CD56+CD39+ dNK subset NOG mice adoptive transfer placental trophoblast cell fate M-CSF

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

Effects of stigma on the quality of lifein patients with epilepsy

引用

Acta Epileptologica 2024年第2期7卷 110-118页

作者： Chunmei Hu Yuping Zhao Zheng Xiao Department of Neurology The First Affiliated Hospital of Chongqing Medical UniversityNO.1 Youyi Rd.ChongqingYuzhong District 400016China Department of Neurology The People’s Hospital of NanchuanChongqing 408400China

Background This study was aimed to evaluate the stigma and quality of life(QoL)in adult patients with epilepsy(PWEs)and explore the relationship between stigma and *** Two hundred and ninety-eight PWEs admitted to the Epilepsy Center of the First Affiliated Hospitalof Chongqing Medical University during September 2020 and March 2021 were enrolled in this *** participantscompleted self-reported questionnaires including the Stigma Scale for Epilepsy and the Quality of Life in EpilepsyInventory-31(QOLIE-31).Results A total of 146(49%)PWEs reported an experience of *** total score of QOLIE-31 and the individualscores of seven subscales(worry about new seizures,emotion,well-being,energy and fatigue,cognitive impairment,medication effect,and social function)were significantly decreased in these patients(P<0.001).Multivariate stepwiselinear regression analysis showed that the annual household income per capita,the number of antiseizure medica-tions and stigma had statistically significant effects on QoL(P<0.05).Among them,stigma had the most significantnegative *** Nearly half of PWEs have experienced ***,lower household income per capita,and polyp-harmacy treatment are associated with poorer *** has the most obvious negative impact.

关键词： Perceived stigma Epilepsy Quality of life

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

Machine Learning-Based Research on Tensile Strength of SiC-Reinforced Magnesium Matrix Composites via Stir Casting

引用

Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 453-466页

作者： Zhihong Zhu Wenhang Ning Xuanyang Niu Yuhong Zhao Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China School of Materials Science and Engineering Collaborative Innovation Center of Ministry of Education and Shanxi Province for High-Performance Al/Mg Alloy MaterialsNorth University of ChinaTaiyuan 030051China Institute of Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110004China

SiC is the most common reinforcement in magnesium matrix composites,and the tensile strength of SiC-reinforced magnesium matrix composites is closely related to the distribution of *** a uniform distribution of SiC requires fine control over the parameters of SiC and the processing and preparation ***,due to the numerous adjustable parameters,using traditional experimental methods requires a considerable amount of experimentation to obtain a uniformly distributed composite ***,this study adopts a machine learning approach to explore the tensile strength of SiC-reinforced magnesium matrix composites in the mechanical stirring casting *** analyzing the influence of SiC parameters and processing parameters on composite material performance,we have established an effective predictive ***,six different machine learning regression models have been developed to predict the tensile strength of SiC-reinforced magnesium matrix *** validation and comparison,our models demonstrate good accuracy and reliability in predicting the tensile strength of the composite *** research findings indicate that hot extrusion treatment,SiC content,and stirring time have a significant impact on the tensile strength.

关键词： Machine learning Stirring casting Magnesium matrix composite Tensile strength

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

Tunable hexagonal boron nitride topological optical delay line in the visible region

引用

Chinese Optics Letters 2024年第5期22卷 124-130页

作者：费宏明武敏林瀚杨毅彪肖连团 College of Physics Taiyuan University of TechnologyTaiyuan 030024China College of Information Engineering Shanxi Vocational University of Engineering Science and TechnologyJinzhong 030619China College of Science RMIT UniversityMelbourneVictoria 3000Australia College of Electronic Information and Optical Engineering Taiyuan University of TechnologyTaiyuan 030024China

Tunability,ultracompact design,high group index,low loss,and broad bandwidth are desired properties for integrated optical delay lines(ODLs).However,those properties are challenging to achieve simultaneously in the visible *** paper proposes a tunable hexagonal boron nitride topological optical delay line(ODL)in the visible region based on valley photonic *** topological edge state from the beard-type boundary allows the achievement of an ultralow group velocity close to zero,which results in a large group index of 629 at 645 ***,we demonstrate tuning of the slow-light wavelength and optical delay times with electrically tunable liquid crystals by applying external *** device has an ultracompact size of 5μm×2.7μm with an optical delay distance of 25a(a is the lattice constant)and a delay time of 12 *** design can provide a new possibility for designing ODLs working in the visible region for optical communication and quantum computing systems.

关键词： valley photonic crystal topological edge states optical delay lines

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

Revealing the Structure-Property Difference of natural Rubber Prepared by Different Methods: Protein and Gel Content are Key Factors

引用

Chinese Journal of Polymer Science 2024年第4期42卷 457-467页

作者： Shao-Qi Huang Jun-Qi Zhang Yong Zhu Ling-Min Kong Lu-Sheng Liao Fu-Quan Zhang Zheng-Tian Xie Jin-Rong Wu State Key Laboratory of Polymer Materials Engineering College of Polymer Science and EngineeringSichuan UniversityChengdu610065China Hainan Provincial Key Laboratory of natural Rubber Processing Agricultural Products Processing Research Institute of Chinese Academy of Tropical Agricultural SciencesZhanjiang524001China

natural rubber (NR) is widely used in various fields including aerospace, military industry and transportation due to its superior elasticity and comprehensive mechanical properties. Nonetheless, the commercial NR prepared by different methods usually exhibits different mechanical properties, primarily due to variations in processing conditions during the conversion from latex to bulk rubber material. Consequently, this poses challenges in scientific research and industrial production of NR. In order to assess the properties of various commercially available NR and identify key structural and compositional components, this study systematically compares and analyzes four representative NR raw materials: air dried sheet (ADS), ribbed smoked sheets (RSS), constant viscidity NR (CV), and whole field latex rubber (WF). The investigation focuses on evaluating their static mechanical behavior, SIC behavior, wear resistance, and fatigue resistance. The findings indicate that protein and gel content exhibit a crucial influence on the NR properties. These constituents contribute to the formation of a high-crosslinking density region, generating a heterogeneous network structure within the rubber. This structure amplifies strains during deformation, leading to earlier and stronger strain-induced crystallization (SIC). Among the four commercial NR brands, RSS demonstrates superior overall mechanical and dynamic properties owing to its high protein and gel content. This study serves as a valuable reference for comprehending the differences in properties among various commercial NR, thereby offering guidance for the actual processing and selection of NR.

关键词： natural rubber Processingmethod Protein Gel content Property

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

Modulating charge separation and transfer for high-performance photoelectrodes via built-in electric field

引用

International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 1126-1146页

作者： Houyan Cheng Peng Liu Yuntao Cui Ru Ya Yuxiang Hu Jinshu Wang Key Laboratory of Advanced Functional Materials of Education Ministry of china Faculty of Engineering and ManufacturingBeijing University of TechnologyBeijing 100124China Key Laboratory of Cryogenic Science and Technology and Beijing Key Lab of Cryo-Biomedical Engineering Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China Inner Mongolia Academy of Science and Technology Hohhot 010020China

Constructing a built-in electric field has emerged as a key strategy for enhancing charge separation and transfer,thereby improving photoelectrochemical ***,considerable efforts have been devoted to this *** review systematically summarizes the impact of built-in electric fields on enhancing charge separation and transfer mechanisms,focusing on the modulation of built-in electric fields in terms of depth and ***,mechanisms and tuning strategies for built-in electric fields are ***,the state-of-the-art works regarding built-in electric fields for modulating charge separation and transfer are summarized and categorized according to surface and interface ***,current strategies for constructing bulk built-in electric fields in photoelectrodes are explored,and insights into future developments for enhancing charge separation and transfer in high-performance photoelectrochemical applications are provided.

关键词： photoelectrochemical water splitting bulk built-in electric field cation intercalation charge separation and 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

Topologically engineering of π-conjugated macrocycles: Tunable emission and photochemical reaction toward multi-cyclic polymers

引用

Chinese Chemical Letters 2024年第10期35卷 233-240页

作者： Yi Liu Peng Lei Yang Feng Shiwei Fu Xiaoqing Liu Siqi Zhang Bin Tu Chen Chen Yifan Li Lei Wang Qing-Dao Zeng Shenzhen Key Laboratory of Polymer Science and Technology Guangdong Research Center for Interfacial Engineering of Functional MaterialsCollege of Materials Science and EngineeringShenzhen UniversityShenzhen 518060China CAS Key Laboratory of Standardization and Measurement for Nanotechnology CAS Center for Excellence in NanoscienceNational Center for Nanoscience andTechnology(NCNST)Beijing100190China Institute of Critical Materials for Integrated Circuits Shenzhen Polytechnic UniversityShenzhen 518055China

The topology of conjugated macrocycles had significant impacts on their photo-physical and photochemical ***,a series ofπ-conjugated macrocycles with diverse topology were synthesized via intramolecular McMurry *** chemical structure and macrocyclic topology were unambiguously confirmed via NMR,MALDI-TOF mass spectra,crystal analysis and scanning tunneling microscopy(STM).Depending on the structural topology and structural rigidity,these cyclic compounds display obviously distinctive emission behavior and photochemical reactions in the solution and in the solid *** phenylene vinylene macrocycle(denoted as MST)exhibiting aggregation-induced emission behavior,was more vulnerable to photo-cyclization in solution and triplet sensitizer promoted photodimerization due to lower strain and more flourishing intramolecular *** UV light irradiation,relatively more flexible MST could yield the anti-dimer via triplet excimer on the HOPG surface confirmed by STM *** contrast,highly constrained bicyclic analogue(named as DMTPE)with central tetraphenylethene core,displayed high emission quantum yields of 68%both in solution and in the solid state,and was relatively inert to photochemical reactions and yield syn-dimer on the surface via singlet excimer involved[2+2]*** on the solution-mediated photo-polymerization of MST moiety,multicyclic porous carbon-rich ribbon connected with four-membered ring was successfully constructed and validated via STM imaging.

关键词： Conjugated macrocycle Scanning tunneling microscopy Aggregation-induced emission Photochemistry Multicyclicribbon

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：