Ciência & Tecnologia dos Materiais最新文献_第10页

New process for simultaneous removal of CO2, SOX and NOX 同时去除CO2、SOX和NOX的新工艺

Ciência & Tecnologia dos Materiais Pub Date : 2016-07-01 DOI: 10.1016/j.ctmat.2016.12.002

S.P. Santos , A.P. Duarte , J.C. Bordado , J.F. Gomes

引用次数: 11

Low-temperature short-time nitriding of Va-group metals, V, Nb and Ta, in uncracked NH3 gas under heating with concentrated solar power (CSP) 聚光太阳能(CSP)加热下未裂解NH3气体中va族金属V、Nb和Ta的低温短时间氮化

Ciência & Tecnologia dos Materiais Pub Date : 2016-07-01 DOI: 10.1016/j.ctmat.2017.02.001

J.C. Fernandes , F.A.C. Oliveira , L.G. Rosa , J. Rodríguez , I. Cañadas , T. Magalhães , N. Shohoji

{"title":"Low-temperature short-time nitriding of Va-group metals, V, Nb and Ta, in uncracked NH3 gas under heating with concentrated solar power (CSP)","authors":"J.C. Fernandes , F.A.C. Oliveira , L.G. Rosa , J. Rodríguez , I. Cañadas , T. Magalhães , N. Shohoji","doi":"10.1016/j.ctmat.2017.02.001","DOIUrl":"10.1016/j.ctmat.2017.02.001","url":null,"abstract":"<div>Over the last two decades, the authors have been using concentrated solar beam as the reaction heat source for synthesizing carbides and nitrides of d-group transition elements in view of usage of ecological renewable energy source in place of conventional heat sources using electricity or natural gas. In recent works, nitriding of VIa-group metals (Cr, Mo, W) and Fe in stream of NH3 gas with suppressed extent of dissociation (uncracked NH3) was attempted under heating with concentrated solar beam. It was demonstrated that mono-nitride δ-MoN of Mo and sub-nitride ɛ-Fe2N of Fe that are known to be impossible to synthesize in N2 gas environment even at elevated N2 gas partial pressure p(N2) up to 300bar were successfully synthesized by the reactions of these metals in stream of NH3 gas under heating with concentrated solar beam up to 800°C.In the present work, nitriding of Va-group metals (V, Nb and Ta) was attempted in stream of NH3 gas under irradiation of concentrated solar beam. After 90min heating in uncracked NH3 under concentrated solar beam up to 800°C, X-ray diffraction (XRD) characterization of the reaction products showed certain extent of nitriding progressed for all the specimens in spite of relatively low reaction temperature for short reaction duration.</div>","PeriodicalId":10198,"journal":{"name":"Ciência & Tecnologia dos Materiais","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2016-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.ctmat.2017.02.001","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85181847","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Virtual bronchoscopy method based on marching cubes and an efficient collision detection and resolution algorithm 基于行进立方体的虚拟支气管镜检测方法和高效的碰撞检测与分辨算法

Ciência & Tecnologia dos Materiais Pub Date : 2016-07-01 DOI: 10.1016/j.ctmat.2015.12.002

Catalin Ciobirca , Teodoru Popa , Gabriel Gruionu , Thomas Lango , Hakon Olav Leira , Stefan Dan Pastrama , Lucian Gheorghe Gruionu

引用次数: 3

Effect of TiO2 nanotubes developed on pure titanium substrates on the mechanical performance of titanium-titanium single-lap adhesive joints 在纯钛基体上制备TiO2纳米管对钛-钛单搭接接头力学性能的影响

Ciência & Tecnologia dos Materiais Pub Date : 2016-07-01 DOI: 10.1016/j.ctmat.2016.02.004

G.C. Papanicolaou, D.V. Portan, G.N. Petropoulos, L.C. Kontaxis

{"title":"Effect of TiO2 nanotubes developed on pure titanium substrates on the mechanical performance of titanium-titanium single-lap adhesive joints","authors":"G.C. Papanicolaou, D.V. Portan, G.N. Petropoulos, L.C. Kontaxis","doi":"10.1016/j.ctmat.2016.02.004","DOIUrl":"10.1016/j.ctmat.2016.02.004","url":null,"abstract":"<div>The aim of the present work is to study the combined effect of TiO2 nanotubes, developed by means of electrochemical anodization on pure titanium adherends, and of the adhesive epoxy resin reinforced with carbon nanotubes (CNTs), on the quasi-static three-point bending behaviour of titanium-titanium single lap adhesive joints. A specific combination of parameters, namely time, type of electrolyte and voltage, has been selected in order to develop nanotubes with optimum geometry in an effort to achieve single lap adhesive joints with enhanced mechanical strength. The mechanical performance of the single lap joints as well as the bonding efficiency of the nano-composite adhesive were studied by means of three point bending and tensile shear tests, while the nano-structural topography was investigated through Scanning Electron Microscopy (SEM) observations. Following the above procedure an increase on the order of 82% in flexural strength for the thus manufactured single-lap adhesive joints was achieved, while the flexural modulus of the joints remained unaffected.</div>","PeriodicalId":10198,"journal":{"name":"Ciência & Tecnologia dos Materiais","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2016-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.ctmat.2016.02.004","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74878927","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

Viscoelastic behaviour and modelling of nano and micro TiO2 powder-epoxy resin composites 纳米和微TiO2粉末-环氧树脂复合材料的粘弹性行为和建模

Ciência & Tecnologia dos Materiais Pub Date : 2016-07-01 DOI: 10.1016/j.ctmat.2016.02.005

G.C. Papanicolaou, L.C Kontaxis, A.E. Manara

{"title":"Viscoelastic behaviour and modelling of nano and micro TiO2 powder-epoxy resin composites","authors":"G.C. Papanicolaou, L.C Kontaxis, A.E. Manara","doi":"10.1016/j.ctmat.2016.02.005","DOIUrl":"10.1016/j.ctmat.2016.02.005","url":null,"abstract":"<div>Epoxy resin composites reinforced with different weight fractions of TiO2 micro-particles 0.2μm in size (1%, 5%, 10%, 15%wt) and of TiO2 nano-particles 21nm in size (0.5%, 1%, 3%wt) were manufactured. The quasi-static mechanical properties of both nano-composites and micro-composites were investigated and compared through tensile testing. The experimental results were predicted and the degree of matrix-particle adhesion and particle dispersion were evaluated, by the Property Prediction Model (PPM) developed by the first author. The composites were also subjected to creep-recovery tests as well as to relaxation tests in order to investigate their viscoelastic behaviour. The experiments were carried out at different filler-weight fractions and loading conditions. Non-linear viscoelastic behaviour was observed in all cases and appropriate models were applied in order to describe, and/or predict the viscoelastic behaviour of all materials tested. A fair agreement between experimental results and theoretical predictions was observed for both viscoelastic and static results.</div>","PeriodicalId":10198,"journal":{"name":"Ciência & Tecnologia dos Materiais","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2016-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.ctmat.2016.02.005","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73864507","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 8

Improved mechanical properties of magneto rheological elastomeric composite with isotropic iron filler distribution 各向同性铁填料分布改善磁流变弹性体复合材料力学性能

Ciência & Tecnologia dos Materiais Pub Date : 2016-07-01 DOI: 10.1016/j.ctmat.2016.03.002

Sneha Samal , Jarmil Vlach , Pavel Kavan

引用次数: 11

A new class of closed-cell aluminium foams reinforced with carbon nanotubes 用碳纳米管增强的新型闭孔泡沫铝

Ciência & Tecnologia dos Materiais Pub Date : 2016-01-01 DOI: 10.1016/j.ctmat.2016.06.003

I. Duarte , E. Ventura , S. Olhero , J.M.F. Ferreira

引用次数: 7

Biomimetic cork-based CeO2 ecoceramics for hydrogen generation using concentrated solar energy 用于聚光太阳能制氢的仿生软木基CeO2陶瓷

Ciência & Tecnologia dos Materiais Pub Date : 2016-01-01 DOI: 10.1016/j.ctmat.2016.04.002

R.C. Pullar , L. Gil , F.A.C. Oliveira

{"title":"Biomimetic cork-based CeO2 ecoceramics for hydrogen generation using concentrated solar energy","authors":"R.C. Pullar , L. Gil , F.A.C. Oliveira","doi":"10.1016/j.ctmat.2016.04.002","DOIUrl":"10.1016/j.ctmat.2016.04.002","url":null,"abstract":"<div>Naturally occurring and sustainable materials can be used as a template to create biomimetic/biomorphic ceramics, known as Ecoceramics (environmentally conscious ceramics). In this work, cork was chosen as template to produce novel ceria (CeO2) ecoceramics, for applications in water splitting for H2 production via direct concentrated solar thermochemical fuel production (TCFP). The cork powder was pyrolised at 900°C and the resulting carbon skeleton was infiltrated with an aqueous CeO2 precursor, and then heated at 1000°C for 2h to produce the ecoceramic. The cellular structure of the cork was maintained, with hexagonal cell dimensions of 20-30μm in diameter, but the grains were nanoscale at ≤100nm. XRD data confirmed that CeO2 was the only crystalline phase obtained. An important feature was that, while the rectangular side walls were maintained to hold the three-dimensionally ordered macroporous (3DOM) cellular cork structure, the rear hexagonal walls were pierced repeatedly through the structure, unlike in the original cork structure, which will allow gasses such as H2 to permeate well into the structure, greatly increasing the reactive area available for catalysis. The next step will be to test the capabilities of both the regular, porous 3DOM structure and the nanoscale grains for thermochemical water splitting to produce hydrogen under direct concentrated solar energy.</div>","PeriodicalId":10198,"journal":{"name":"Ciência & Tecnologia dos Materiais","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.ctmat.2016.04.002","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81946380","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

Deformation behaviour of self-expanding magnesium stents based on auxetic chiral lattices 基于缺手性晶格的自膨胀镁支架的变形行为

Ciência & Tecnologia dos Materiais Pub Date : 2016-01-01 DOI: 10.1016/j.ctmat.2016.01.002

V.H. Carneiro , H. Puga

{"title":"Deformation behaviour of self-expanding magnesium stents based on auxetic chiral lattices","authors":"V.H. Carneiro , H. Puga","doi":"10.1016/j.ctmat.2016.01.002","DOIUrl":"10.1016/j.ctmat.2016.01.002","url":null,"abstract":"<div>Current stenting solutions commonly employ metal alloys and are permanent. This fact has the consequence of diverse long term risks for the patients, e.g. Restenosis, late-term stent Thrombosis, etc. One possible solution to attenuate these problems is the use of polymer or metallic based bioabsorbable stents that tend to be degraded by corrosion and completely eliminated after their scaffolding duties are fulfilled. Additionally, there is a need to find new ways of deploying these devices. A route to fulfill this goal, can be the design of stents that eliminate the necessity of balloon expansion and are able to self-expand by their own deformation mechanism, for example by possessing auxetic behavior. The objective of this study is the modeling of a stent that reveals auxetic behavior and is composed by a biodegradable material (AZ91D Magnesium alloy), to embrace both recent tendencies on stenting designs. It is shown that the defined stent modeling is able to expand when stretched (auxetic behavior) and reveals a deformation mechanism that may be interesting for further development. In conclusion, the combination of both biodegradable and auxetic characteristics shown in this study may be a future step in the evolution of these medical devices.</div>","PeriodicalId":10198,"journal":{"name":"Ciência & Tecnologia dos Materiais","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.ctmat.2016.01.002","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83671685","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 16

Geometrical and mechanical analysis of various types of cellular metals 各种类型多孔金属的几何和力学分析

Ciência & Tecnologia dos Materiais Pub Date : 2016-01-01 DOI: 10.1016/j.ctmat.2016.06.004

M. Vesenjak, Z. Ren

引用次数: 1