Journal: Materials最新文献_第3页

Thermal and Dielectric Behavior Studies of Poly(Arylene Ether Sulfone)s with Sulfonated and Phosphonated Pendants 磺化和膦化垂饰聚芳醚砜的热学和介电行为研究

Journal: Materials Pub Date : 2016-08-24 DOI: 10.1155/2016/7271959

S. D. Ganesh, Vasantakumar K. Pai, M. Kariduraganavar, Madhu B. Jayanna

{"title":"Thermal and Dielectric Behavior Studies of Poly(Arylene Ether Sulfone)s with Sulfonated and Phosphonated Pendants","authors":"S. D. Ganesh, Vasantakumar K. Pai, M. Kariduraganavar, Madhu B. Jayanna","doi":"10.1155/2016/7271959","DOIUrl":"https://doi.org/10.1155/2016/7271959","url":null,"abstract":"The present paper discusses the aspects of the synthesizing valeric acid based poly(ether sulfone)s with active carboxylic acid pendants (VALPSU) from solution polymerization technique via nucleophilic displacement polycondensation reaction among 4,4′-dichlorodiphenyl sulfone (DCDPS) and 4,4′-bis(4-hydroxyphenyl) valeric acid (BHPA). The conditions necessary to synthesize and purify the polymer were investigated in some detail. The synthesized poly(ether sulfone)s comprise sulfone and ether linkages in addition to reactive carboxylic acid functionality; these active carboxylic acid functional groups were exploited to hold the phenyl sulphonic acid and phenyl phosphonic acid pendants. The phenyl sulphonic acid pendants in VALPSU were easily constructed by altering active carboxylic acid moieties by sulfanilic acid using N,N′-dicyclohexylcarbodiimide (DCC) mediated mild synthetic route, whereas the latter one was built in two steps. Initially, polyphosphoric acid condensation with VALPSU by 4-bromoaniline and next straightforward palladium catalyzed synthetic route, in both of which acidic pendants are clenched by polymer backbone via amide linkage. Without impairing the primary polymeric backbone modified polymers were prepared by varying the stoichiometric ratios of respective combinations. All the polymers were physicochemically characterized and pressed into tablets; electrical contacts were established to study the dielectric properties. Finally, the influence of the acidic pendants on the dielectric properties was examined.","PeriodicalId":17611,"journal":{"name":"Journal: Materials","volume":"70 1","pages":"1-10"},"PeriodicalIF":0.0,"publicationDate":"2016-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77397711","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: 2

The Energy Loss of α-Particles in Ferromagnetic Nickel at Phase Transition 铁磁镍中α-粒子相变的能量损失

Journal: Materials Pub Date : 2016-08-17 DOI: 10.1155/2016/4576194

U. V. Khadke

引用次数: 3

CNT Reinforced Silver Nanocomposites: Mechanical and Electrical Studies 碳纳米管增强银纳米复合材料:机械和电气研究

Journal: Materials Pub Date : 2016-08-17 DOI: 10.1155/2016/8629206

D. Kumar, Sonia Nain, Neena, H. Pal, Ravi Kumar

引用次数: 4

Enhancement of Light Localization in Hybrid Thue-Morse/Periodic Photonic Crystals 杂化Thue-Morse/周期光子晶体中光局域化的增强

Journal: Materials Pub Date : 2016-08-14 DOI: 10.1155/2016/9471312

R. Asmi, N. Ali, M. Kanzari

引用次数: 5

Optimization of Cutting Parameters during Dry Turning of Austenitic Stainless Steel Using nc-AlTiN/Si3N4, TiAlN, and TiN Coated Inserts nc-AlTiN/Si3N4、TiAlN和TiN涂层刀片干式车削奥氏体不锈钢切削参数优化

Journal: Materials Pub Date : 2016-07-28 DOI: 10.1155/2016/3495698

K. V. Prasad, R. Pal, V. Rajendraprasad

引用次数: 1

Cement Pastes and Mortars Containing Nitrogen-Doped and Oxygen-Functionalized Multiwalled Carbon Nanotubes 含氮掺杂和氧功能化多壁碳纳米管的水泥浆和砂浆

Journal: Materials Pub Date : 2016-02-28 DOI: 10.1155/2016/6209192

Mauricio Martínez-Alanis, F. López‐Urías

{"title":"Cement Pastes and Mortars Containing Nitrogen-Doped and Oxygen-Functionalized Multiwalled Carbon Nanotubes","authors":"Mauricio Martínez-Alanis, F. López‐Urías","doi":"10.1155/2016/6209192","DOIUrl":"https://doi.org/10.1155/2016/6209192","url":null,"abstract":"Cement pastes and mortars based on ordinary Portland cement containing nitrogen-doped multiwalled carbon nanotubes (MWCNT-Nx) or oxygen-functionalized multiwalled carbon nanotubes (MWCNT-Ox) are investigated. To incorporate MWCNTs into the cementitious matrix, the as-produced carpets are dispersed over periods of 1 and 2 hours in distilled water at pH levels of 1 and 7. The cement pastes are prepared by adding 0.1 wt% of MWCNTs to cement powder, followed by characterization with SEM and X-ray diffraction (XRD) at an early age (first hours of hydration). The mortars are mechanically characterized during the hydration process for a period of 28 days. SEM characterization of cement pastes revealed that the carbon nanotubes are well incorporated in the cementitious matrix, with the hydrated cement grains interconnected by long carbon nanotubes. XRD characterizations demonstrated that, during the hydration of cement pastes, different peaks emerged that were associated with ettringite, hydrated calcium silicate, and calcium hydroxide, among other structures. Results of the compressive strength measurements for mortars simultaneously mixed with MWCNT-Nx and MWCNT-Ox reached an increment of approximately 30% in compressive strength. In addition, density functional theory calculations were performed in nitrogen-doped and oxygen-functionalized carbon nanotubes interacting with a cement grain.","PeriodicalId":17611,"journal":{"name":"Journal: Materials","volume":"17 1","pages":"1-16"},"PeriodicalIF":0.0,"publicationDate":"2016-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78200046","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: 3

Influence of Grain Boundary Character and Annealing Time on Segregation in Commercially Pure Nickel 工业纯镍中晶界特征和退火时间对偏析的影响

Journal: Materials Pub Date : 2016-02-16 DOI: 10.1155/2016/4597271

S. Welsh, M. Kapoor, O. Underwood, R. Martens, G. Thompson, Jeffrey L. Evans

引用次数: 7

Behavioural Change according to the Si/Al Ratio of Successive Na-Mordenites Observed through Their Dielectric Relaxation during Water Vapour Adsorption Process 通过介电弛豫观察连续na -丝光沸石在水蒸气吸附过程中Si/Al比值的行为变化

Journal: Materials Pub Date : 2016-02-03 DOI: 10.1155/2016/7532951

S. Diaby

{"title":"Behavioural Change according to the Si/Al Ratio of Successive Na-Mordenites Observed through Their Dielectric Relaxation during Water Vapour Adsorption Process","authors":"S. Diaby","doi":"10.1155/2016/7532951","DOIUrl":"https://doi.org/10.1155/2016/7532951","url":null,"abstract":"The experimental study of water vapour adsorption phenomenon on a zeolite, by dielectric relaxation measurement, makes it possible to determine the variations in the exchangeable cation hopping activation energy, on the surface of the solid, in relation to the number of adsorbed molecules. The present work shows that it is possible to explain the change observed in the energy, by means of simple assumptions based, on the one hand, on the models used in order to simulate the adsorption process and, on the other hand, on the distribution of the molecules adsorbed near the exchangeable cations. Thus, the phenomenological interpretation suggested here, about the change in the exchangeable cation hopping energy, obtained by dielectric relaxation measurement, makes us with a mind to conceive a simple method for explaining the results leading to new information on the organization of the first adsorbed molecules on the surface of the studied zeolite. Then, it can be verified that these conclusions confirm the assumptions already developed for interpreting the inferences from previous experiments carried out by means of other techniques.","PeriodicalId":17611,"journal":{"name":"Journal: Materials","volume":"23 1","pages":"1-10"},"PeriodicalIF":0.0,"publicationDate":"2016-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75159404","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: 2

Investigation of the Physical and Molecular Properties of Asphalt Binders Processed with Used Motor Oils 废旧机油加工沥青粘结剂的物理和分子性能研究

Journal: Materials Pub Date : 2015-12-21 DOI: 10.1155/2015/632534

Mohyeldin Ragab, M. Abdelrahman

{"title":"Investigation of the Physical and Molecular Properties of Asphalt Binders Processed with Used Motor Oils","authors":"Mohyeldin Ragab, M. Abdelrahman","doi":"10.1155/2015/632534","DOIUrl":"https://doi.org/10.1155/2015/632534","url":null,"abstract":"In this work we investigated the performance aspects of addition of used motor oils (UMO) to neat and crumb rubber modified asphalts (CRMA) and related that to the change of molecular size distribution of modified asphalt’s fractions; asphaltenes, saturates, naphthene aromatics, and polar aromatics. Based on the results of temperature sweep viscoelastic tests, addition of crumb rubber modifier (CRM) alone or with UMO results in the formation of internal network within the modified asphalt. Based on the results of short and long term aged asphalts, the utilization of combination of UMO and CRM enhanced the aging behavior of asphalt. Bending beam rheometer was utilized to investigate the low temperature behavior of UMO modified asphalts. Based on those tests, the utilization of the UMO and CRM enhanced the low temperature properties of asphalts. Based on the results of the asphalt separation tests and the Gel Permeation Chromatography (GPC) analysis, it was found that saturates and naphthene aromatics are the two asphalt fractions that have similar molecular size fractions as those of UMO. However, UMO only shifts the molecular sizes of saturates after interaction with asphalt. Results also show that polar aromatics pose higher molecular size structures than UMO.","PeriodicalId":17611,"journal":{"name":"Journal: Materials","volume":"33 1","pages":"1-9"},"PeriodicalIF":0.0,"publicationDate":"2015-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82152336","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: 9

Structural and Thermophysical Studies of Composite Na-Cobaltite Electrospun Nanofibers 复合钠钴酸盐静电纺纳米纤维的结构和热物理研究

Journal: Materials Pub Date : 2015-11-15 DOI: 10.1155/2015/838957

Fatima-tuz-Zahra, M. Anis-Ur-Rehman

{"title":"Structural and Thermophysical Studies of Composite Na-Cobaltite Electrospun Nanofibers","authors":"Fatima-tuz-Zahra, M. Anis-Ur-Rehman","doi":"10.1155/2015/838957","DOIUrl":"https://doi.org/10.1155/2015/838957","url":null,"abstract":"Polymeric nanofibers have been produced in the last few years by electrospinning of polymer solutions. Polyvinyl alcohol (PVA) was the selected polymer for the preparation of nanofibers. Processing parameters like flow rate, needle gauge, needle to collector distance, and molarity of the solution have been optimized during electrospinning process. Sol-gel method has been used for the preparation of thermoelectric cobaltite nanoparticles having composition NaCoO2. Sol-gel combined electrospinning technique was used to prepare the composites of the NaCoO2 with PVA nanofibers. X-ray diffraction (XRD), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC) have been used for the structural analysis of the prepared samples. Scanning electron microscopy (SEM) was used to observe the morphology of the prepared fibers. SEM micrographs showed that, by increasing the flow rate, diameter of the fibers increased from 185 nm to 200 nm. Two-probe method and Advantageous Transient Plane Source (ATPS) were used to study the electrical and thermal transport properties, respectively. Thermal conductivity and electrical conductivity showed a direct dependence on temperature. It was observed that particles, sample has lower thermal conductivity (0.610 W/m-K) as compared to that of composite nanofibers (1.129 W/m-K). The measurements reported are novel and are useful for energy applications.","PeriodicalId":17611,"journal":{"name":"Journal: Materials","volume":"2 1","pages":"1-8"},"PeriodicalIF":0.0,"publicationDate":"2015-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76571907","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: 1