检索结果-南通市图书馆

Experimental study on the wear evolution of different PVD coated tools under milling operations of LDX2101 duplex stainless steel

引用

Advances in Manufacturing 2023年第1期11卷 158-179页

作者： Vitor F.C.sousa francisco J.G.silva Ricardo Alexandre Jose s.Fecheira Gustavo Pinto Andresa Baptista IsEP-school of Engineering Polytechnic of PortoRua Dr.António Bernardino de Almeida4314200–072PortoPortugal INEGI-Driving science and Innovation Rua Dr.Roberto Frias4004200–465PortoPortugal TEandM-Technology Engineering and MaterialsS.A.Parque Industrial do TaveiroLotes 41-423045–504TaveiroPortugal

Duplex stainless steels are being used on applications that require,especially,high corrosion resistance and overall good mechanical properties,such as the naval and oil-gas exploration *** components employed in these industries are usually obtained by machining,however,these alloys have low machinability when compared to conventional stainless *** this work,a study of the wear developed when milling duplex stainless-steel,LDX 2101,is going to be presented and evaluated,employing four types of milling tools with different geometries and coatings,while studying the influence of feed rate and cutting length in the wear of these *** used have been provided with two and four flutes,as well as three different coatings,namely:TiAlN,TiAlsiN and *** cutting behavior of these tools was analyzed;data relative to the cutting forces developed during the process were obtained;and roughness measurements of the machined surfaces were *** tools were then submitted to scanning electron microscope(sEM)analysis,enabling the identification of the wear mechanisms that tools were subjected to when machining this material,furthermore,the early stages of these mechanisms were also *** this work was done with the goal of relating the machining parameters and cutting force values obtained,identifying,and discussing the wear patterns that were observed in the coating and tools after the milling tests,providing further information on the machining of these alloys.

关键词： Duplex stainless-steel Milling Tool coatings surface roughness Wear mechanisms

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

Immediate and late effects of chronic stress in the testes of prepubertal and adult rats

引用

Asian Journal of Andrology 2018年第4期20卷 385-390页

作者： Carina T Ribeiro Diogo B De souza Waldemar s Costa francisco J B sampaio Marco A Pereira-sampaio Urogenital Research Unit State University of Rio de Janeiro Rio de Janeiro RJ 20551-030 Brazil Department of Morphology Fluminense Federal University Niteroi RJ 24210-150 Brazil

The objective of this study was to investigate the effects of chronic stress on the testes of prepubertal and adult rats and to evaluate whether any alterations could be reversed when stress induction is ended. seventy-six male rats were assigned to eight groups depending on the type of treatment （control or stressed）, the age at which stress was initiated （prepubertal or adult）, and the time of evaluation （immediate or late）. stress stimuli were applied for 6 weeks. stressed prepubertal and adult rats evaluated immediately after the last stress stimulus were included in sP-I and sA-I groups, respectively. The late prepubertal （sP-L） and adult （sA-L） groups of stressed rats were evaluated 6 weeks after the last stress stimulus. Age-matched rats were used as controls （CP-I, CA-I, CP-L, and CA-L groups）. Application of stress stimuli to rats in the sP-I group resulted in body weight and seminiferous tubule diameter reduction. The rats in the sA-I group also showed several functional （testosterone level and sperm parameter） and morphological （testicular weight and seminiferous tubule diameter） reductions. The rats in the sP-L group showed increased body weight and intertubular compartment volumetric and absolute densities and reduced tubular compartment volumetric density. The rats in the sA-L group presented only reduced sperm viability. stress stimuli promoted changes in the rats in all the study groups. The testes of the adult rats were the most affected by chronic stress. However, the stressed adult rats recovered well from the testicular alterations.

关键词： chronic stress morphometry rat testis

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

Differential effects of environmental climatic variables on parasite abundances in blue tit nests during a decade

引用

Integrative Zoology 2022年第4期17卷 511-529页

作者： francisco CAsTAÑO-VÁZQUEZ santiago MERINO Evolutionary Ecology Museo Nacional de Ciencias Naturales CSICMadridSpain

Models on climate change have predicted an increase of temperature over the earth’s surface with potential drastic effects on living *** analyzed the relationships between climatic conditions(temperature,rainfall,and wind speed)and the abundance of blood-sucking flying insects(biting midges and blackflies)and nest-dwelling ectoparasites(mites,fleas,and blowflies)collected from blue tit nests during bird breeding seasons for a period of 10 *** temperature,rainfall,and wind speed showed significant differences among *** and wind speed increased during the period of study while rainfall *** midge,blackfly,and blowfly abundances increased across years but not flea and mite *** date decreased and brood size increased across *** of year variation,parasites were related to climatic *** example,biting midge,blowfly,mite,and flea abundances were positive and significantly related to average *** also found a positive and significant relationship between abundances of Haemoproteus infections and biting midge abundances during the first year of life of birds out of ***,abundance and prevalence of Lankesterella infections in yearlings were positive and significantly related to mite abundances during the year of birth of *** and Lankesterella infections were also significantly related to climatic variables and Haemoproteus and Lankesterella infections increased across *** addition,body condition of adult females and males were negatively related to flea larvae and blowfly abundance *** body condition was also negatively related to biting midge *** in climatic conditions across years could therefore affect several parasites of birds but also to birds themselves.

关键词： biting midges blackfly blowfly Haemoproteus Lankesterella rainfall temperature

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

Measurement of Anomalous Radon Gas Emanation Across the Yammouneh Fault in southern Lebanon: A Possible Approach to Earthquake Prediction

引用

International Journal of Disaster Risk science 2015年第3期6卷 250-266页

作者： Mohammed A.Kobeissi francisco Gomez Charles Tabet Lebanese Atomic Energy Commission Lebanese National Council for Scientific Research Department of Geological sciences University of Missouri Lebanese National Council for scientific Research BeirutLebanon

The eastern Mediterranean region is an active tectonic setting that includes the Dead sea Transform Fault, which forms the boundary between the African and the Arabian Plates and crosses Lebanon from south to north, striking in a restraining bend around 25–30°NE. The major structural feature in Lebanon is the Yammouneh Fault, which reaches to syria and southern Turkey in a north–south direction. Measurements of radon gas concentration and exhalation rates in two locations along the southern segment of the Yammouneh Fault in south Lebanon were performed. Two profiles in the El-Khiam basin and Blat pull-apart basin and perpendicular to the Yammouneh Fault trace were analyzed. An approximate fault width 25–30 m wide was determined in the El-Khiam study area. Temporal increase of radon concentration was measured and correlated with stress/strain tectonic activity and stress drops along the studied fault segment *** variable radon concentrations were detected during one of the measurements where an earthquake occurred in the region of Tiberias Lake in northern Palestine along the Yammouneh Fault in the study area. Measurements of radon concentration along a station’s profile in Blat village did not show any radon anomalous variation due to the discontinuity along the fault(pull-apart), and possible absence of stress and energy accumulation along the Yammouneh Fault line in that location.

关键词： CR-39 Detector Earthquake prediction Exhalation rate Lebanon Radon stress/strain

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

Linking plant metabolism and immunity through methionine biosynthesis

引用

Molecular Plant 2022年第1期15卷 6-8页

作者： francisco Escaray Amelia Felipo-Benavent Pablo Vera Instituto de Biología Molecular y Celular de Plantas Universidad Politécnica de Valencia-C.S.I.CCiudad Politécnica de la InnovaciónEdificio 8EIngeniero Fausto Elios/n46022 ValenciaSpain

Plants respond to pathogenic cues with a transcriptional reprog-ramming that leads to de novo production of defense-related pro-teins and a huge variety of secondary metabolites(e.g.,phyto-alexins,phenolics,etc.).Activation of these host defenses,which contribute to halt the intruder as part of the resistance,im-plies an increased demand for metabolic energy and carbon skel-etons derived from primary metabolism(Bolton,2009).

关键词： metabolism immunity Bolton

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

Geography of Talent in China During 2000-2015:An Eigenvector spatial Filtering Negative Binomial Approach

引用

Chinese Geographical science 2021年第2期31卷 297-312页

作者： GU Hengyu francisco ROWE LIU Ye sHEN Tiyan school of Government Peking UniversityBeijing 100871China Geographic Data science Lab Department of Geography and PlanningUniversity of LiverpoolLiverpool L69United Kingdom school of Geography and Planning Sun Yat-sen UniversityGuangzhou 510275China Guangdong Key Laboratory for Urbanization and Geo-simulation Sun Yat-sen UniversityGuangzhou 510275China

The increase in China’s skilled labor force has drawn much attention from policymakers,national and international firms and *** how educated talent locates and re-locates across the country can guide future policy discussions of equality,firm localization and service *** studies have tended to adopt a static cross-national approach providing valuable insights into the relative importance of economic and amenity differentials driving the distribution of talent in ***,few adopt longitudinal analysis to examine the temporal dynamics in the stregnth of existing *** released official statistical data now enables space-time analysis of the geographic distribution of talent and its determinants in *** four-year city-level data from national population censuses and 1%population sample surveys conducted every five years between 2000 and 2015,we examine the spatial patterns of talent across Chinese cities and their underpinning drivers evolve over *** reveal that the spatial distribution of talent in China is persistently unequal and spatially concentrated between 2000 and *** also shows gradually strengthened and significantly positive spatial autocorrelation in the distribution of *** eigenvector spatial filtering negative binomial panel is employed to model the spatial determinants of talent *** indicate the influences of both economic opportunities and urban amenities,particularly urban public services and greening rate,on the distribution of *** results highlight that urban economic-and amenity-related factors have simultaneously driven China’s talent’s settlement patterns over the first fifteen years of the 21st century.

关键词： talent distribution determinants eigenvector spatial filtering panel data analysis China

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

systemic epigallocatechin gallate protects against retinal degeneration and hepatic oxidative stress in the P23H-1 rat

引用

Neural Regeneration Research 2022年第3期17卷 625-631页

作者： Lorena Perdices Lorena Fuentes-Broto francisco segura Ana Cavero Elvira Orduna-Hospital Gema Insa-sánchez Ana Isabel sánchez-Cano Laura Fernández-sánchez Nicolás Cuenca Isabel Pinilla Aragón Institute for Health Research(IIs Aragón) ZaragozaSpain Pharmacology Physiology&Legal and Forensic MedicineUniversity of ZaragozaZaragozaSpain Department of Applied Physics University of ZaragozaZaragozaSpain Health sciences Faculty San Jorge UniversityVillanueva de GállegoSpain Department of Ophthalmology Miguel Servet University HospitalZaragozaSpain Department of Physiology Genetics and MicrobiologyUniversity of AlicanteAlicanteSpain Department of surgery Gynecology and ObstetricsUniversity of ZaragozaZaragozaSpain/Department of OphthalmologyLozano Blesa University HospitalZaragozaSpain

Retinitis pigmentosa(RP) is a group of inherited retinal disorders that lead to photoreceptor *** has been reported to be related to oxidative stress,autophagy,and inflammation.(-)-Epigallocatechin gallate(EGCG),the most abundant catechin-based flavonoid in green tea leaves,has significant antioxidant,anti-carcinogenic,antimicrobial,and neuroprotective ***,given its low molecular weight and hydrophilic properties,can cross the blood-retinal barrier and is able to reach different ocular tissues such as the lens,cornea,and *** has been shown to provide retinal protection against ischemia;sodium nitroprusside-,N-methyl-D-aspartate-,lipopolysaccharide-,light-,sodium iodate-,or H2 O2-induced damage and diabetic *** suggests that systemic EGCG administration has the potential to protect against retinal degenerative or neurodegenerative diseases such as *** aim of this work was to investigate whether EGCG can protect against RP progression in the animal P23 H line 1,the model of *** P23 H rats were crossed with pigmented Long Evans rats to produce offspring exhibiting the clinical features of *** P23 H rats were treated via intraperitoneal injection with saline or EGCG at a dose of 25 mg/kg every week from P100 to P160 and then compared to wild-type Long Evans *** treated with EGCG showed better visual and retinal electrical function with increased contrast sensitivity and b-wave values compared with those observed in P23 H rats treated with *** reduced lipid peroxidation and increased total antioxidant capacity and catalase and superoxide dismutase *** differences were observed in visual acuity,nitrate levels,nitrite levels or glutathione s-transferase *** conclusion,EGCG not only reduced the loss of visual function in P23 H rats but also improved the levels of antioxidant enzymes and reduced oxidative *** study was approved by the Institutional Animal Care and Use Committee(CE

关键词： antioxidants contrast sensitivity electroretinogram green tea neurodegeneration oxidative stress retinal degeneration retinitis pigmentosa systemic visual acuity

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

Multifunctional antimicrobial chlorhexidine polymers by remote plasma assisted vacuum deposition

引用

Frontiers of Chemical science and Engineering 2019年第2期13卷 330-339页

作者： Ana Mora-Boza francisco J.Aparicio Maria Alcaire Carmen López-santos Juan P.Espinós Daniel Torres-Lagares Ana Borrás Angel Barranco Consejo superior de Investigaciones Cientificas. Instituto de Ciencia de Materiales de sevilla (CsIC-Universidad de sevilla) c/Americo Vespucio 49 41092 SevillaSpain Facultad de Odontologia Universidad de Sevilla (USE) c/Avicena41009 SevillaSpain

Novel antibacterial materials for implants and medical instruments are essential to develop practical strategies to stop the spread of healthcare associated infections. This study presents the synthesis of multifunctional antibacterial nanocoatings on polydimethylsiloxane (PDMs) by remote plasma assisted deposition of sublimated chlorhexidine powders at low pressure and room temperature. The obtained materials present effective antibacterial activity against Escherichia coli K12, either by contact killing and antibacterial adhesion or by biocide agents release depending on the synthetic parameters. In addition, these multifunctional coatings allow the endure hydrophilization of the hydrophobic PDMs surface, thereby improving their biocompatibility. Importantly, cell-viability tests conducted on these materials also prove their non-cytotoxicity, opening a way for the integration of this type of functional plasma films in biomedical devices.

关键词： plasma polymers conformal plasma deposition chlorhexidine bactericide PDMs biocompatibility

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

A sylvester-Based IMEXMethod via Differentiation Matrices for solving Nonlinear Parabolic Equations

引用

Communications in Computational Physics 2013年第9期14卷 1001-1026页

作者： francisco de la Hoz Fernando Vadillo Department of Applied Mathematics Statistics and Operations ResearchFaculty of Science and TechnologyUniversity of the Basque Country UPV/EHUBarrio Sarriena S/N48940 LeioaSpain

In this paper we describe a new pseudo-spectral method to solve numerically two and three-dimensional nonlinear diffusion equations over unbounded domains,taking Hermite functions,sinc functions,and rational Chebyshev polynomials as basis *** idea is to discretize the equations by means of differentiation matrices and to relate them to sylvester-type equations by means of a fourth-order implicit-explicit scheme,being of particular interest the treatment of three-dimensional sylvester equations that we *** resulting method is easy to understand and express,and can be implemented in a transparent way by means of a few lines of *** test numerically the three choices of basis functions,showing the convenience of this new approach,especially when rational Chebyshev polynomials are considered.

关键词： semi-linear diffusion equations pseudo-spectral methods differentiation matrices Hermite functions sinc functions rational Chebyshev polynomials IMEX methods sylvester equations blow-up

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

EQUIVALENT UNIFORM DOsE sENsITIVITY TO CHANGEs IN ABsORBED DOsE DIsTRIBUTION

引用

International Journal of Biomathematics 2013年第1期6卷 129-142页

作者： francisco CUTANDA-HENRIQUEZ sILVIA VARGAs-CAsTRILLON Hospital General Universitario Gregorio Mara~sn Calle Doctor Esquerdo 46 28007 Madrid Spain Universidad Politdcnica de Madrid Ciudad Universitaria s/n 28040 Madrid Spain

Treatment planning in external beam radiation therapy （EBRT） utilizes dose volume histograms （DVHs） as optimization and evaluation tools. They present the fraction of planning target volume （PTV） receiving more than a given absorbed dose, against the absorbed dose values, and a number of radiobiological indices can be computed with their help. Equivalent uniform dose （EUD） is the absorbed dose that, uniformly imparted, would yield the same biological effect on a tumor as the dose distribution described by the DVH. Uncertainty and missing information can affect the dose distribution, therefore DVHs can be modeled as samples from a set of possible outcomes. This work studies the sensitivity of the EUD index when a small change in absorbed dose distribution takes place. EUD is treated as a functional on the set of DVHs. Defining a Levy distance on this set and using a suitable expansion of the functional, a very simple expression for a bound on the variation of EUD when the dose distribution changes is found. This bound is easily interpreted in terms of standard treatment planning practice.

关键词： Equivalent uniform dose DVH von Mises differential.

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：