检索结果-南通市图书馆

Review of micromachining of ceramics by etching

在线全文

学校读者我要写书评

暂无评论

中国有色金属学会会刊：英文版 2009年第B09期19卷 1-16页

作者： H.t.tING K.A.AbOU-EL-HOSSEIN H.b.CHUA School of Engineering and Science Curtin University of Technology (Sarawak Campus) Department of Mechatronics Nelson Mandela Metr opolitan University

In the last two decades, there has been an enormous surge in interest in ceramic materials and, as a result, there have been significant advances in their development and applications. their inherent properties, such as capability of operating at temperatures far above metals, high level of hardness and toughness, low coefficient of thermal expansion and high thermal conductivity rendered ceramics to be one of the leading engineering materials. Many research works have been conducted in the past few years on machining of advanced ceramics using different processing methods in order to obtain a better surface roughness, higher material removal rate and improved tool life. Micromachining using chemical etching is one of those methods that do not involve the problem of tool life and direct tool-work piece contact. However, only a few research works have been done on micromachining of ceramics using chemical etching. Hence, study of chemical machining of advanced ceramics is still needed as the process has found wide application in the industry because of its relative low operating costs. In this work, we summarize the recent progresses in machining of different types of advanced ceramics, material processing methods such as wet etching and dry etching, and finally the prospects for control of material removal rate and surface quality in the process of ceramic micromachining.

关键词：陶瓷材料化学蚀刻表面粗糙度机械加工过程陶瓷加工刀具寿命材料去除率高温作业

toughening of Epoxy Resin with Solid Amine terminated Poly(ethy-lene glycol) benzoate and Effect of Red Mud Waste Particles

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & technology 2008年第2期24卷 272-278页

作者： b.C.Samanta t.Maity S.Dalai A.K.banthia Department of Chelnistrv and Chemical technology Vidyasagar UniversityMidnapore-721102India Materials Science Centre Indian Institute of TechnologyKharagpur-721302India

An investigation was carried out to modify the toughness of triethylene tetramine cured DGEbA （diglycidyl ether of bisphenol-A） resin using solid amine terminated poly （ethylene glycol） benzoate （AtPEGb） as modifier with and without red mud waste particles. the solid AtPEGb modifier synthesized from the acid catalyzed esterification reaction of poly （ethylene glycol）（PEG） and 4-amino benzoic acid was characterized by Fourier transform infrared spectroscopy （Ft-IR） and ^1H-NMR （nuclear magnetic resonance） spectroscopies, viscosity measurements, and solubility parameter calculation. the unfilled and red mud waste filled modified epoxy networks were evaluated with impact, adhesive, tensile, flexural and thermal properties by differential scanning calorimetry （DSC）, thermogravimetric （tG） and dynamic mechanical analysis （DMA）. the effect of modifier concentration and red mud waste particles on toughening behavior was also investigated. the optimum properties were obtained at 12.5 phr （parts per hundred parts of resin） concentration of the modifier. the AtPEGb modified cured epoxy was thermally stable up to 315℃. the morphology on fracture surfaces of cured epoxy was also analyzed by scanning electron microscopy （SEM）.

关键词： Epoxy toughness Adhesive Morphology

titanate Nanorods Modified with Nanocrystalline ZnS Particles and their Photocatalytic Activity on Pollutant Removal

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & technology 2016年第11期32卷 1122-1128页

作者： G.Naudin t.Entradas b.barrocas O.C.Monteiro Faculte de Chimie Universite Pierre et Marie Curie (UPMC) Batiment F 3e etage 4 placeJussieu 75005 Paris France Centro de Quimica e bioquimica Faculdade de Ciencias Universidade de Lisboa 1749-016 Lisboa Portugal

Aiming to produce materials with enhanced photocatalytic properties, the synthesis of new crystalline nanocomposites by combining titanate nanorods（tNR） with ZnS nanocrystallites is described in this *** tNR modification was accomplished by an in situ nucleation and growth process of ZnS *** diethyldithiocarbamate was used as the metal chalcogenide precursor. the prepared materials were structural, morphological and optical characterized by X-ray diffraction, transmission electron microscopy and high resolution transmission electron microscopy, energy dispersive spectroscopy and powder diffuse reflectance spectra. Crystalline Zn S nanoparticles were obtained as a homogeneous and continuous layer, covering completely the tNR surface. the application of these new nanocomposite materials on photocatalytic degradation of pollutants was investigated. First, the evaluation of hydroxyl radical formation, using the terephthalic acid as probe, was studied. Afterwards, the adsorption and photodegradation of safranine-t, used here as a model pollutant molecule, was investigated. the obtained data indicate that the prepared nanocomposites have potential to be used as photocatalysts for organic pollutant *** best removal results（97% removal） were obtained using the 0.01 Zn S/HtNR sample as catalyst（0.2 g/L; 10 ppm safranin-t solution） with a combination of a low dye adsorption（20%） and a high dye photocatalytic degradation（77%）.

关键词： Nanocomposite materials Surface modification Photocatalysis Adsorption ability Optical properties

Miniaturized antenna design for communication establishment of peer-to-peer communication in the oil pipelines

在线全文

学校读者我要写书评

暂无评论

Petroleum Research 2021年第3期6卷 291-302页

作者： E.b.Priyanka S.thangavel t.Kalavathidevi Department of Automobile Engineering Kongu Engineering CollegeErode638060India Department of Mechatronics Engineering Kongu Engineering CollegeErode638060India Department of Electronics and Instrumentation Engineering Kongu Engineering CollegeErode638060India

In the oil pipeline world,wireless automation plays an important role through integrated electronic technology in antenna design for robust *** technology gets evaluated by its power consumption and compactness to afford a better solution to real-world problems with better sophistication to adopt a modernized wireless *** that,the Iot(Internet of things)technology plays a predominant role by combining with Artificial Intelligence to optimize and revolute the characterization of data *** the data communication is initiated,the main contributor to the transmission is the miniaturized antenna holding different types in its structure and *** acquires the required radio spectrum channel with the advanced multi coding modulating technique by utilizing token ring mesh topology for the data transfer with acquired data *** chapter describes the design and fabrication of a miniaturized antenna using MEMS technology(Micro-Electro-Mechanical System)and its different types using INtELLISUItE software to get suited for better communication in oil *** on the application,it also enumerates the choices of micro or nanoantennas with its specification upholding data adopting techniques with modulation schemes to support Iot applications.

关键词： Antenna MEMS Channel width Optimization Oil pipelines and Iot

Magnetohydrodynamics hemodynamics hybrid nanofluid flow through inclined stenotic artery

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

Applied Mathematics and Mechanics(English Edition) 2023年第3期44卷 459-476页

作者： b.K.SHARMA R.GANDHI t.AbbAS M.M.bHAttI Department of Mathematics Birla Institute of Technology and SciencePilani 333031India Department of Mathematics Division of Science and TechnologyUniversity of EducationLahore 54770Pakistan College of Mathematics and Systems Science Shandong University of Science and TechnologyQingdao 266590Shandong ProvinceChina

the present study aims to perform computational simulations of twodimensional(2D)hemodynamics of unsteady blood flow via an inclined overlapping stenosed artery employing the Casson fluid model to discuss the hemorheological properties in the arterial region.A uniform magnetic field is applied to the blood flow in the radial direction as the magneto-hemodynamics effect is *** entropy generation is discussed using the second law of *** influence of different shape parameters is explored,which are assumed to have varied shapes(spherical,brick,cylindrical,platelet,and blade).the Crank-Nicolson scheme solves the equations and boundary conditions governing the *** a given critical height of the stenosis,the key hemodynamic variables such as velocity,wall shear stress(WSS),temperature,flow rate,and heat transfer coefficient are computed.

关键词： overlapping stenosis hematocrit-dependent viscosity Au-Cu/blood hybrid nanofluid entropy generation shape effect

Urban invaders are not bold risk-takers: a study of 3 invasive lizards in Southern California

在线全文

学校读者我要写书评

暂无评论

Current Zoology 2020年第6期66卷 657-665页

作者： breanna J.Putman Gregory b.Pauly Daniel t.blumstein Department of Ecology and Evolutionary biology University of CaliforniaLos AngelesCA90095-1606USA Department of Herpetology and Urban Nature Research Center Natural History Museum of Los Angeles County900 Exposition BoulevardLos AngelesCA90007USA Department of biology California State UniversitySan BernardinoCA 92407USA

biological invasions threaten biodiversity worldwide,and therefore,understanding the traits of successful invaders could mitigate their *** comm only invasive species do well in disturbed habitats,such as urban environments,and their abilities to effectively respond to disturbarices could con tribute to their ***,there are non invasive species that also do well in disturbed *** question remains whether urban invaders behave differently in urban environments than noninvaders,which could suggest an"urban-exploiting"*** Southern California,the co-occurrence of in vasive Italia n wall lizards Pod arc is siculus,brown anoles Anolis sagrei,and green anoles ***,and native western fence lizards Sceloporus occidentalis offers an opportunity to test whether invasives exhibit consistent differences in risk-taking within human-altered habitats compared with a native *** predicted that invasive lizards would exhibit more bold behavior by having shorter flight-initiation distances(FIDs)and by being found farther from a refuge(behaviors that would presumably maximize foraging in low-risk environments).Invasive populations had similar or longer FIDs,but were consistently found at distances closer to a ***,invasive lizards in urban habitats were not bolder than a native *** on nearby refuges might help species successfully invade urban habitats,and if a general pattern,may pose an added challenge in detecting or eliminating them.

关键词： antipredator boldness escape behavior invasion reptile urban ecology

Influence of towing speed on effectiveness of rolling dynamic compaction

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

Journal of Rock Mechanics and Geotechnical Engineering 2020年第1期12卷 126-134页

作者： brendan t.Scott Mark b.Jaksa Peter W.Mitchell School of Civil Environmental and Mining EngineeringThe University of AdelaideSouth Australia5005Australia Aurecon AdelaideSouth Australia5000Australia

the influence of towing speed on the effectiveness of the 4-sided impact roller using earth pressure cells(EPCs)is *** field trials were undertaken;the first trial used three EPCs placed at varying depths between 0.5 m and 1.5 m with towing speeds of 9-12 km/*** second used three EPCs placed at a uniform depth of 0.8 m,with towing speeds of 5-15 km/*** findings from the two trials confirmed that towing speed influences the pressure imparted to the ground and hence compactive *** paper proposes that the energy imparted to the ground is best described in terms of work done,which is the sum of the change in both potential and kinetic *** practice of using either kinetic energy or gravitational potential energy should be avoided as neither can accurately quantify rolling dynamic compaction(RDC)when towing speed is varied.

关键词： Rolling dynamic compaction(RDC) Optimum towing speed Ground improvement

targeting circular RNAs as a therapeutic approach: current strategies and challenges

在线全文

学校读者我要写书评

暂无评论

Signal transduction and targeted therapy 2021年第6期6卷 1718-1731页

作者： Alina t.He Jinglei Liu Feiya Li burton b.Yang Sunnybrook Research Institute TorontoONCanada Department of bioinformatics ATCGene IncGuangzhouChina Department of Laboratory Medicine and Pathobiology University of TorontoTorontoONCanada

Significant progress has been made in circular RNA(circRNA)research in recent *** evidence suggests that circRNAs play important roles in many cellular processes,and their dysregulation is implicated in the pathogenesis of various *** are highly stable and usually expressed in a tissue-or cell type-specific ***,they are currently being explored as potential therapeutic ***-of-function and loss-of-function approaches are typically performed using circRNA expression plasmids and RNA interference-based strategies,*** strategies have limitations that can be mitigated using nanoparticle and exosome delivery ***,recent developments show that the cre-lox system can be used to knockdown circRNAs in a cell-specific *** still in the early stages of development,the CRISPR/Cas13 system has shown promise in knocking down circRNAs with high specificity and *** this review,we describe circRNA properties and functions and highlight their significance in *** summarize strategies that can be used to overexpress or knockdown circRNAs as a therapeutic ***,we discuss major challenges and propose future directions for the development of circRNA-based therapeutics.

关键词： therapeutic specificity circular

bound in continuum states and induced transparency in mesoscopic demultiplexer with two outputs

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

Chinese Physics b 2020年第12期29卷 429-437页

作者： Z Labdouti t Mrabti A Mouadili E H El boudouti F Fethi b Djafari-Rouhani LPMR Dèpartement de PhysiqueFacultèdes SciencesUniversitèMohammed IOujdaMorocco LStA Dèpartement de PhysiqueFacultèPolydisciplinaire de LaracheUniversitèAbdelmalek EssaadiTètouanMorocco LPMCER Dèpartement de PhysiqueFacultèdes Sciences et Techniques de MohammediaUniversitèHassan IICasablancaMorocco IEMN UMR CNRS 8520UFR de PhysiqueUniversitède Lille59655 Villeneuve d'AscqFrance

We investigate the electronic transport in a simple mesoscopic cross structure made of two wires(stubs)grafted at the same point along a quantum *** show that the structure may exhibit important phenomena such as bound in continuum(bIC)*** states are transformed into electromagnetically induced transparency(EIt)resonance by detuning slightly the lengths of the *** last phenomenon is used to propose and study a mesoscopic demultiplexer device with an input waveguide and two output *** give closed-form expressions of the geometrical parameters that allow a selective transfer of a given state in the first waveguide without perturbing the second *** effect of temperature on the transmission resonances is also examined by using Landauer-büttiker *** analytical results of the dispersion relation and transmission and reflection coefficient are obtained using the Green's function method.

关键词： mesoscopic structure demultiplexer device bound states in continuum(bIC) EIt resonance