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41.
42.
Muhammad Hanafiah Nurmawati Parayil Kumaran Ajikumar Ravindranath Renu Suresh Valiyaveettil 《Advanced functional materials》2008,18(20):3213-3218
Fabrication of two and three‐dimensional nanostructures requires the development of new methodologies for the assembly of molecular/macromolecular objects on substrates in predetermined arrangements. Templated self‐assembly approach is a powerful strategy for the creation of materials from assembly of molecular components or nanoparticles. The present study describes the development of a facile, template directed self‐assembly of (metal/organic) nanomaterials into periodic micro‐ and nanostructures. The positioning and the organization of nanomaterials into spatially well‐defined arrays were achieved using an amphiphilic conjugated polymer‐aided, self‐organization process. Arrays of honeycomb patterns formed from conjugated C12PPPOH film with homogenous distribution of metal/organic nanomaterials. Our approach offers a straightforward and inexpensive method of preparation for hybrid thin films without environmentally controlled chambers or sophisticated instruments as compared to multistep micro‐fabrication techniques. 相似文献
43.
Logic behaviour of an ECL OR/NOR gate under different physical faults is examined. It is shown that the conventional stuck-at fault modelling may be inadequate for obtaining a sufficiently high fault coverage. A new augmented stuck-at fault model is presented which provides a better coverage of physical failures.<> 相似文献
44.
This paper describes the need for and the design of, a knowledge based process diagnostic system. A prototype system is implemented using Intellicorp's Knowledge Engineering Environment (KEE). The system is being implemented at a planned new assembly plant. 相似文献
45.
Ce0.9Gd0.1O1.95 powders were synthesized by spray drying and successive calcinations. The phase purity, BET surface area, and particle morphology of as-sprayed and calcined powders were characterized. After calcination above 300 °C, the powders were single phase and showed a BET surface area of 68 m2/g when calcined at 300 °C. The conductivity, in air, of sintered pellets was measured by electrochemical impedance spectroscopy (EIS) and it was found to be comparable with literature values. The activation energy for the total conductivity was around 0.83 eV. The powder calcined at lower temperature showed better sinterability and higher total conductivity due to an increased bulk conductivity. 相似文献
46.
47.
Thomas O.J. Blomfeldt Richard T. Olsson Mohan Menon David Plackett Eva Johansson Mikael S. Hedenqvist 《大分子材料与工程》2010,295(9):796-801
A new way of producing rigid or semi‐rigid foams from vital wheat gluten using a freeze‐drying process is reported. Water/gluten‐based mixtures were frozen and freeze‐dried. Different foam structures were obtained by varying the mixing process and wheat gluten concentration, or by adding glycerol or bacterial cellulose nanofibers. MIP revealed that the foams had mainly an open porosity peaking at 93%. The average pore diameter ranged between 20 and 73 µm; the sample with the highest wheat gluten concentration and no plasticizer had the smallest pores. Immersion tests with limonene revealed that the foams rapidly soaked up the liquid. An especially interesting feature of the low‐wheat‐concentration foams was the “in situ” created soft‐top‐rigid‐bottom foams.
48.
Preparation of anchored ceramic coatings on metal substrates: a modified sol-gel technique using colloidal silica sol 总被引:1,自引:0,他引:1
M. F. M. Zwinkels S. G. Järås P. Govind Menon Knut I. Åsen 《Journal of Materials Science》1996,31(23):6345-6349
A single-step dip-coating technique was developed to produce stable films or washcoats of controlled thickness, surface area and pore-size distribution on alumina whisker-covered metal substrates (both flat plates and monoliths). Dip-coating slurries were prepared by dispersing fine porous powder in a colloidal silica sol. The method provided control over coating thickness and coating properties, such as pore-size distribution and surface area. The coating thickness could be varied between approximately 2 and 40 m by selecting slurry composition and withdrawal speed in the dipping procedure. The pore-size distribution and surface area could be varied by changing type and amount of porous filler material in the dipping slurry. Uniform and bimodal pore-size distributions were obtained using silica and ZSM-5 molecular sieves, respectively, yielding coatings with surface areas between 60 and 400 m2g–1. 相似文献
49.
R. Murugasami P. Vivekanandhan S. Kumaran R. Suresh Kumar T. John Tharakan 《Advanced Powder Technology》2017,28(2):506-513
In this research, the influence of process parameters such as sintering temperature and current during alloying and densification of silicon-germanium (Si80-Ge20) powder mixture using spark plasma sintering (SPS) was reported. Si80-Ge20 powder mixture was consolidated at the temperature range 900–1200 °C with 40 MPa pressure for 5 min. soaking. X-ray diffraction (XRD) study was made on sintered compacts to confirm the Si(Ge) alloy formation. Scanning electron microscope (SEM) was used to understand the morphology, particle size and distribution of un-milled and milled Si80-Ge20 powder mixture. Transmission electron microscope (TEM) study was made on milled Si80-Ge20 powder mixture and bulk SiGe alloy to confirm the nano-crystallinity and alloy formation. Fracture toughness of sintered bulk SiGe alloy was determined from Palmqvist cracks geometry model using Vickers hardness testing. It is understood that, during spark plasma sintering nano-structured Si80-Ge20 powder simultaneously increases the densification and reaction kinetics. It helps to achieve homogenous nanostructured SiGe alloy of near theoretical density. The superior hardness and benchmarked fracture toughness (KIC) values of 630 VHN and 2.19 MPa√m was achieved for SiGe alloy sintered at 1200 °C, respectively. 相似文献
50.
Vacuum deposited MoO3-V2O5 films of different molar concentrations have been used for DC electrical conductivity studies at different temperatures.
The optical absorption spectra of MoO3-V2O5 films of different molar concentrations have been measured. From these measurements it is found that optical band gap and
activation energy vary with molar concentration of MoO3-V2O5 films. 相似文献