检索结果-南通市图书馆

Cotton pads-derived carbon materials/reduced graphene oxide modified with polypyrrole for electrode of supercapacitors

引用

Journal of Energy Chemistry 2024年第7期94卷 41-53页

作者： Ofelia MArias-Pinedo Elvis OLopez ivonne emonje RSoria-Martinez Antony Bazan-Aguilar Clemente Alfredo Luyo Caycho Gabriel Angel Planes Angelica Maria Baena-Moncada Laboratorio de Investigacion de Electroquimica Aplicada Facultad de Ciencias de la Universidad Nacional de IngenieriaAv.Tupac Amaru 210RimacLimaPeru Department of Experimental Low Energy Physics Brazilian Center for Research in Physics(CBPF)Rio de Janeiro22290-180Brazi Universidad Tecnologica del Peri Av.Arequipa 26515046 LimaPeru Centeror theevelopmentof Adanced Materials and Nanotechlogy Universidad NacionaldeIngeneria33LimaP Departamento de Quimica Universidad Nacional de Rio CuartoInstituto de Investigaciones en Tecnologias Energeticas y Materiales Avanzados(IITEMA)Ruta Nac.36Km 601(X5804BYA)RioCuartoCordobaArgentina

This study investigates the influence of electropolymerization conditions on the deposition of polypyrrole(PPy)onto cotton-derived carbon fiber(CF)modified with reduced graphene oxide(rGO)for supercapacitors applications using an experimental/theorical *** surface modification of CF by rGO and/or by PPy electrodeposited at 10,25 and 50 mV s^(-1) was thoroughly examined physicochemical and *** electrodes comprising CF-rGo-PPy,synthesized via electropolymerization at 25 mV s^(-1),demonstrated a remarkable increase in capacitance,showcasing~742 F g^(-1) compared to 153 F g^(-1) for ***,N_(2)-surface area,XPS,and TD-DFT approach revealed that the higher capacitance observed in CF-rGo-PPy electrodes underscores the influence of morphology and charged nitrogen species on the electrochemical performance of these modified ***,this electrode material achieves a specific capacitance retention of~96%of their initial capacitance after 10000 cycles at 0.5 A g^(-1) measured in a two-electrodes cell *** work also discusses the influence of the scan rate used for pyrrole electropolymerization on the pseudocapacitance contribution of PPy and its possible effect on the porosity of the *** results highlight the importance of appropriate electropolymerization conditions that allow obtaining the synergistic effect between CF,rGO and PPy.

关键词： Supercapacitors Cotton pads-derived carbon fibers rGO PPy TD-DFT

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

Potential distribution of a montane rodent (Cricetidae, Handleyomys chapmani) through time in Mexico: the importance of occurrence data

引用

Journal of Mountain Science 2021年第8期18卷 2024-2033页

作者： CANO ivonne GUEVARA Lazaro Department of Zoology Institute of BiologyNational Autonomous University of Mexico04510Mexico CityMexico

Ecological Niche Modeling uses the geographic coordinates of species presence records as the primary input to estimate potential geographic *** is little known whether carrying out rigorous data pre-processing is necessary before building niche models to be transferred to different time *** we compared the current,past,and future potential distributions projected by niche models built from two different databases,an open-access database and a database compiled ad hoc,for Handleyomys chapmani,a rodent closely associated with montane cloud forests in *** models predicted different spatial patterns of climatic suitability for the three periods *** on our current knowledge of cloud forest species in Mexico,the distributions predicted by the model built from the ad hoc database are more ecologically realistic than those obtained from the open-access *** models built using the open-access database were particularly inaccurate at the limits of the geographic range,predicting larger,more diffuse distributions for the three *** conclude that pre-processing occurrence data is crucial for mountain species,as the number of localities and even minor inaccuracies in the geographic coordinates can translate into very different climatic conditions due to abrupt altitudinal ***,the predicted shifts in the potential distribution of *** over time indicate that this species is highly susceptible to climate change.

关键词： Cloud forests Ecological Niche Modeling Handleyomys chapmani Maxent Rodentia

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

Study on inverter fault-tolerant operation of PMSM DTC

引用

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第2期9卷 156-164页

作者： Yznaga Blanco ivonne Dan SUN Yi-kang HE School of Electrical Engineering Zhejiang University Hangzhou 310027 China Researches and Electrical Tests Center Cujae University Havana City 19390 Cuba

This paper presents an investigation of inverter fault-tolerant operation for a permanent magnet synchronous motor （PMSM） direct torque control （DTC） system under various inverter faults. The performance of a faulty standard 6-switch inverter driven PMSM DTC system is analyzed. To avoid the loss or even disaster caused by the inverter faults, a topology-modified inverter with fault-tolerant capability is introduced, which is reconfigured as a 3-phase 4-switch inverter. The modeling of the 4-switch inverter is then analyzed and a novel DTC strategy with a unique nonlinear perpendicular flux observer and feedback compensation scheme is proposed for obtaining a continuous, disturbance-flee drive system. The simulation and experimental results demonstrate that the proposed inverter fault-tolerant PMSM DTC system is able to operate stably and continuously with acceptable static and pretty good dynamic performance.

关键词： Permanent magnet synchronous motor (PMSM) Direct torque control (DTC) Fault-tolerant operation Four-switchinverter Nonlinear perpendicular flux observer

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

The Bulk-Surface Virtual Element Method for Reaction-Diffusion PDEs:Analysis and Applications

引用

Communications in Computational Physics 2023年第3期33卷 733-763页

作者： Massimo Frittelli Anotida Madzvamuse ivonne Sgura Department of Mathematics and Physics“E.De Giorgi” University of SalentoVia per Arnesano73100 LecceItaly Department of Mathematics University of British Columbia1984 Mathematics RoadVancouverBC V6T 1Z2Canada Department of Mathematics School of Mathematical and Physical SciencesUniversity of SussexBrightonBN19QHUK Department of Mathematics and Applied Mathematics University of PretoriaPrivate Bag x 20Hatfield0028South Africa.

Bulk-surface partial differential equations(BS-PDEs)are prevalent in manyapplications such as cellular,developmental and plant biology as well as in engineeringand material *** numerical methods for BS-PDEs in three space dimensions(3D)are *** this work,we present a bulk-surface virtual elementmethod(BS-VEM)for bulk-surface reaction-diffusion systems,a form of semilinearparabolic BS-PDEs in *** previous studies in two space dimensions(2D),the3D bulk is approximated with general polyhedra,whose outer faces constitute a flatpolygonal approximation of the *** this reason,the method is restricted tothe lowest order case where the geometric error is not *** BS-VEM guaranteesall the advantages of polyhedral methods such as easy mesh generation andfast matrix assembly on general *** advantages are much more relevantthan in *** allowing for general polyhedra,general nonlinear reaction kineticsand general surface curvature,the method only relies on nodal values without needingadditional evaluations usually associated with the quadrature of general *** latter is particularly costly in *** BS-VEM as implemented in thisstudy retains optimal convergence of second order in space.

关键词： Bulk-surface PDEs bulk-surface reaction-diffusion systems polyhedral meshes bulksurface virtual element method convergence.

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

Canonical Workflows in Simulation-based Climate Sciences

引用

Data Intelligence 2022年第2期4卷 212-225页

作者： ivonne Anders Karsten Peters-von Gehlen Hannes Thiemann German Climate Computing Center(DKRZ) BundesstraBe 45aD-20146 HamburgGermany

In this paper we present the derivation of Canonical Workflow Modules from current workflows in simulation-based climate science in support of the elaboration of a corresponding framework for simulationbased *** first identified the different users and user groups in simulation-based climate science based on their reasons for using the resources provided at the German Climate Computing Center(DKRZ).What is special about this is that the DKRZ provides the climate science community with resources like high performance computing(HPC),data storage and specialised services,and hosts the World Data Center for Climate(WDCC).Therefore,users can perform their entire research workflows up to the publication of the data on the same *** analysis shows,that the resources are used by two primary user types:those who require the HPC-system to perform resource intensive simulations to subsequently analyse them and those who reuse,build-on and analyse existing *** then further subdivided these top-level user categories based on their specific goals and analysed their typical,idealised workflows applied to achieve the respective project *** find that due to the subdivision and further granulation of the user groups,the workflows show apparent ***,similar"Canonical Workflow Modules"can be clearly made *** modules are"Data and Software(Re)use","Compute","Data and Software Storing","Data and Software Publication","Generating Knowledge"and in their entirety form the basis for a Canonical Workflow Framework for Research(CWFR).It is desirable that parts of the workflows in a CWFR act as FDOs,but we view this aspect ***,we reflect on the question whether the derivation of Canonical Workflow modules from the analysis of current user behaviour still holds for future systems and work processes.

关键词： Canonical Workflow Fair Digital Objects HPC infrastructures Data services Climate science

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

四开关逆变器供电永磁同步电机直接转矩控制系统转矩脉动抑制

引用

中国电机工程学报 2007年第21期27卷 47-52页

作者：孙丹何宗元 ivonne Yznaga Blanco 贺益康浙江大学电气工程学院浙江省杭州市310027

永磁同步电机直接转矩控制(PMSM DTC)系统的转矩脉动问题一直被广泛关注,特别是在四开关逆变器供电系统中,由于可用电压矢量减少,转矩脉动更加严重。空间矢量调制(SVM)是一种常用的消除电力谐波的调制技术,更可用于电机控制中转矩脉动... 详细信息

永磁同步电机直接转矩控制(PMSM DTC)系统的转矩脉动问题一直被广泛关注,特别是在四开关逆变器供电系统中,由于可用电压矢量减少,转矩脉动更加严重。空间矢量调制(SVM)是一种常用的消除电力谐波的调制技术,更可用于电机控制中转矩脉动的削减。该文针对四开关逆变器供电PMSM DTC系统的特殊性,采用了一种新型SVM方法,分析了等效零矢量模拟技术,将传统SVPWM调制中的劈零思想引入到空间矢量的合成上。仿真及实验结果验证了该新型SVM DTC方法大大减小了转矩脉动,且仍保持了DTC系统固有的快速转矩动态响应。

关键词：永磁同步电机直接转矩控制四开关逆变器容错运行空间矢量调制

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

Complexity of molecular alterations impacts pancreatic cancer prognosis

引用

World Journal of Gastrointestinal Oncology 2013年第1期5卷 1-3页

作者： ivonne Regel Bo Kong Philipp Bruns Christoph W Michalski Jrg Kleeff Department of Surgery Technische Universitt München

Individualized cancer treatment(*** therapy) based on molecular alterations has emerged as an important strategy to improve the current standardof-care chemotherapy.A large number of studies have demonstrated the importance of biomarkers not only in predicting prognosis but more importantly in predicting the response towards *** example,amplification or mutation status of the two biomarkers HER2(human epidermal growth factor 2) and BRCA(breast cancer) can be used to decide on a specific targeted therapy in breast ***,no biomarkers with a similar clinical impact have been identified in pancreatic ductal *** many genome-wide and proteome-based high-throughput studies have identified candidate genes or proteins as promising biomarkers,none of them were eventually transferred into the clinical ***,the most reliable markers for predicting prognosis are still the tumor stage and grade and biomarkers for therapy response remain *** reason lies in the lack of systemic approaches to analyze the complexity of dominating cancer pathways and the impact of such signal complexity on prognosis and therapy response.

关键词： Pancreatic cancer Diagnostic markers Biomarkers Targeted therapy Prognosis Pathways

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

PMSM DTC系统逆变器故障的模糊神经网络诊断(英文)

引用

电机与控制学报 2008年第2期12卷 132-138,146页

作者： YZNAGA BLANC0 ivonne 孙丹贺益康浙江大学电气工程学院浙江杭州310027 Researches and Electrical Tests Center Cujae University of Havana CityHavana 19390Cuba

针对永磁同步电机(PMSM)直接转矩控制(DTC)系统中常见的电力电子逆变器故障,提出了一种基于智能策略的诊断方法。根据PMSM DTC系统逆变器故障的特性,建立了一个自适应神经模糊网络的模型,选择PMSM的电流量作为故障检测和诊断的信号源,... 详细信息

针对永磁同步电机(PMSM)直接转矩控制(DTC)系统中常见的电力电子逆变器故障,提出了一种基于智能策略的诊断方法。根据PMSM DTC系统逆变器故障的特性,建立了一个自适应神经模糊网络的模型,选择PMSM的电流量作为故障检测和诊断的信号源,对系统正常及故障状态下的电流特性进行了分析,并利用训练好的模糊神经网络进行逆变器的故障诊断。仿真结果表明,该方法仅需检测电机的一相电流便可直接实现逆变器多种常见故障的诊断,摒弃了复杂的信号变换,同时节约了系统成本,保障了故障系统容错策略的实施。

关键词：自适应模糊神经技术直接转矩控制永磁同步电机逆变器故障

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

Single nucleotide polymorphism in the tumor necrosis factor-alpha gene affects inflammatory bowel diseases risk

引用

World Journal of Gastroenterology 2008年第29期14卷 4652-4661页

作者： Lynnette R Ferguson Claudia Huebner ivonne Petermann Richard B Gearry Murray L Barclay Pieter Demmers Alan McCulloch Dug Yeo Han Discipline of Nutrition the University of AucklandPrivate Bag 92019 Auckland 1142 New Zealand Department of Gastroenterology Christchurch HospitalChristchurch 8140 New Zealand Crop and Food Research Mosgiel 9053 New Zealand AgResearch Limited Mosgiel 9053 New Zealand

AIM: To investigate the role that single nucleotide polymorphisms (SNPs) in the promoter of the tumour necrosis factor-alpha (TNF-α) gene play in the risk of inflammatory bowel diseases (IBDs) in a New Zealand population, in the context of international studies. METHODS: DNA samples from 388 patients with Crohn's disease (CD), 405 ulcerative colitis (UC), 27 indeterminate colitis (IC) and 201 randomly selected controls, from Canterbury, New Zealand were screened for 3 common polymorphisms in the TNF-α receptor: -238 G→A, -308 G→A and -857C→T, using a TaqmanR assay. A meta-analysis was performed on the data obtained on these polymorphisms combined with that from other published studies. RESULTS: Individuals carrying the -308 G/A allele had a significantly (OR = 1.91, χ2 = 17.36, P < 0.0001) increased risk of pancolitis, and a 1.57-fold increased risk (OR = 1.57, χ2 = 4.34, P = 0.037) of requiring a bowel resection in UC. Carrying the -857 C/T variant decreased the risk of ileocolonic CD (OR = 0.56, χ2 =4.32, P = 0.037), and the need for a bowel resection (OR = 0.59, χ2 = 4.85, P = 0.028). The risk of UC was reduced in individuals who were smokers at diagnosis, (OR = 0.48, χ2 = 4.86, P = 0.028). CONCLUSION: TNF-α is a key cytokine known to play a role in inflammatory response, and the locus for the gene is found in the IBD3 region on chromosome 6p21, known to be associated with an increased risk for IBD. The -308 G/A SNP in the TNF-α promoter is functional, and may account in part for the increased UC risk associated with the IBD3 genomic region. The -857 C/T SNP may decrease IBD risk in certain groups. Pharmaco- or nutrigenomic approaches may be desir- able for individuals with such affected genotypes.

关键词： Tumour necrosis factor alpha Singlenucleotide polymorphisms Inflammatory boweldiseases Crohn's disease Ulcerative colitis

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

Tentative Identification of Phytochemicals and Antioxidant Activities during Fruit-Ripening on Chamaedorea radicalis Mart.

引用

Phyton-International Journal of Experimental Botany 2020年第2期89卷 361-373页

作者： Gerardo Montelongo-Ruiz Yolanda del Rocio Moreno-Ramirez Maria Cruz Juarez-Aragon NohemiNino-Garcia Reyna ivonne Torres-Acosta Torres-Castillo Jorge Ariel Universidad Autonoma de Tamaulipas Instituto de Ecologia AplicadaCiudad Victoria87019Mexico Universidad Autonoma de Tamaulipas Unidad Academica Multidisciplinaria ManteCiudad Mante89840Mexico

This work aims to determine the phytochemical characterization of the pericarp of Chamaedorea radicalis *** as a non-timber product with potential to obtain phytochemicals with potential applications in the *** from *** were grouped in four ripening stages named as S1,S2,S3 and S4,according to maturity;S1 the most unripe stage and S4 the completely ripe *** of total phenolic compounds,free radical scavenging activities and total flavonoid contents using spectrophotometric methods were ***,the tentative identification of phytochemicals during fruit ripening was done using *** phenolic compound(TPC)content ranged from 7.24 to 12.53 mg gallic acid equivalents per gram of fresh weight(mg GAE/g FW).Total flavonoids(TF)contents ranged from 0.163 to 0.23 mg of quercetin equivalents per g FW(mg QE/g FW).Free radical scavenging activity against DPPH and ABTS radicals varied from 40.80 to 53.68 and from 22.29 to 37.76 mmol Trolox equivalents g FW(mmol TE/g FW),*** assay in vitro by FRAP(ferric reducing antioxidant power)method showed that S3 was the highest level with antioxidant power while S4 was the lowest with Red ripeness stage showed the lowest contents for all *** spectrometry allowed detection of 26 compounds,including phenolics,alkaloids and ***,Kaempferol 3-neohesperidoside and the four saponins identified were present in all ripeness *** phytochemical identification and the spectrophotometric determinations showed that the pericarp of *** presented antioxidants and compounds related to alkaloids,phenolics and *** presence and abundance of each phytochemical regarding each ripeness stage should be considered.

关键词： Metabolite identification palm free radical scavenging phenolic compounds saponins

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：