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51.
M. Balasubramanian M. K. Jain S. K. Bhattacharya A. S. Abhiraman 《Journal of Materials Science》1987,22(11):3864-3872
The effects of stabilization conditions on the formation of a consolidated carbon fibre structure from two acrylonitrile-based precursor fibres, one containing itaconic acid as comonomer and the other a commercial precursor, have been studied. The progression of changes in elemental composition and properties such as sonic modulus, electrical resistance and density in a continuous, low temperature (1200° C) carbonization process are reported for the first time. A criterion based on attaining a composition dependent critical density in stabilization is proposed for avoiding the formation of a hollow core in carbon fibres processed continuously at reasonably rapid rates. Aspects related to the development of open and closed micropores in the carbon fibre structure and the possible mechanisms for the formation of a hollow core in carbonization are also discussed. 相似文献
52.
Lim Lim Hwee S. Balakumar S. Mahadevan Zhou Mei Sheng Alex See M. Rahman A. Senthilkumar 《Journal of Electronic Materials》2001,30(12):1478-1482
In this paper, we investigate the effects of integration schemes on the STI-CMP performance of two polishers, as well as the
influence of consumables and process parameters. The experiment was based on both the blanket-oxide wafers and the patterned
wafers processed using 0.18 μm technology. The polishing capability was evaluated, based on the results collected using metrology
tools such as Opti-probe, Tencor profiler; atomic force microscope (AFM), and x-ray-scanning electron microscopy (X-SEM) analysis. 相似文献
53.
R. R. N. Sailaja B. G. Girija Giridhar Madras N. Balasubramanian 《Journal of Materials Science》2008,43(1):64-74
A new biobased composite was developed by adding soy flour (SF) to polypropylene (PP). This composite shows an enhanced tensile
strength and modulus but decrease in elongation at break. The compatibilizer (coupling agent) appears to have a synergistic
effect on tensile strength. The presence of the compatibilizer improves the dispersion of SF in the PP matrix. The addition
of glycerol plasticizer to the composite improves the processability resulting in improved performance, as compared to composites
without glycerol plasticizer. The optimal compatibilizer content appears to be 6%. 相似文献
54.
双重图形需要更新更苛刻的刻蚀能力,要求低于1.5nm CD均匀性、图形收缩和原位多层刻蚀。 相似文献
55.
G. Mahendran V. Balasubramanian T. Senthilvelan 《The International Journal of Advanced Manufacturing Technology》2009,42(7-8):689-695
In this investigation, Mg–Cu dissimilar materials are joined by diffusion bonding process. The principal difficulty when joining Mg–Cu lies in the existence of hard-to-remove oxide films on the magnesium surfaces and the formation of brittle metallic interlayers and oxide inclusions in the bond region. In this investigation, an attempt was made to develop diffusion bonding windows for effective joining of AZ31B Magnesium and commercial grade copper alloys. Joints were fabricated using different combination of process parameters such as bonding temperature, bonding pressure and holding time. The bonding quality was checked by microstructure analysis and lap shear tensile test. Based on the results, diffusion bonding windows were constructed, and they are presented in this paper. These windows will act as reference maps for selecting appropriate diffusion bonding process parameters to get good quality bonds for Mg–Cu alloys. 相似文献
56.
N. Balasubramanian R.S. Mishra K. Krishnamurthy 《Journal of Materials Processing Technology》2009,209(8):3696-3704
Commercially available compact heat exchangers are currently fabricated in several steps by joining multiple tubes, or by independently fabricating and joining fluid channels. Friction stir channeling (FSC) is a simple and innovative technique of manufacturing heat exchangers in a single step by creating continuous, integral channels in a monolithic plate in a single pass. FSC relies on the frictional heat generated between the tool material and the metal workpiece to soften and deform the material to facilitate the creation of a continuous channel. The channel shape, size, and integrity depend on the processing parameters and the tool design. In this paper the structural characteristics and the relationship between the channel features and the processing parameters are discussed. FSC is being developed as a technique for manufacturing heat exchangers. The channel is characterized by roughness features on the inside, which can be analyzed using optical microscopy techniques. 相似文献
57.
Chengkuo Lee Radhakrishnan R. Chii-Chang Chen Jing Li Thillaigovindan J. Balasubramanian N. 《Lightwave Technology, Journal of》2008,26(7):839-846
Conventionally a line defect in the photonic crystal (PhC) is used to create a waveguide for light propagation through the PhC. A PhC based filter is designed by introducing micro-cavities within the line defect so as to form the resonant bandgap structure for PhC. Such a PhC waveguide (PhCWG) filter shows sharp resonant peak in output wavelength spectrum. We proposed a suspended silicon bridge structure comprising this PhCWG filter structure. Since the output resonant wavelength is sensitive to the shape of air holes and defect length of the micro-cavity. Shift of the output resonant wavelength is observed for suspended PhCWG beam structure under particular force loading. In other words, the induced strain modifies the shape of air holes and the spacing among them. Such an effect leads to shift of resonant wavelength. Under optical detection limitation of 0.1 nm for resonant wavelength shift, the sensing capability of this nanomechanical sensor is derived as that vertical deformation is 20-25 nm at the center and the smallest strain is 0.005% for defect length. This innovative design conceptualizes a new application area for PhCs, i.e., the nanometer-scale physical sensors for strains and forces. 相似文献
58.
Surfactant‐mediated synthesis of polyhydroxybutyrate (PHB) nanoparticles for sustained drug delivery
Senthilkumar Pachiyappan Dawn Shanmuganatham Selvanantham Sree Samanvitha Kuppa Saipriya Chandrasekaran Antony Vincent Samrot 《IET nanobiotechnology / IET》2019,13(4):416
In this study, polyhydroxybutyrate (PHB) nanoparticles were synthesised following nanoprecipitation method having different solvents and surfactant (Tween 80) concentrations. In this study, PHB nanoparticles were encapsulated with curcumin and subjected for sustained curcumin delivery. Both the curcumin loaded and unloaded PHB nanoparticles were characterised using FTIR, SEM, and AFM. Sizes of the particles were found to be between 60 and 300 nm. The drug encapsulation efficiency and in vitro drug release of the nanoparticles were analysed. Antibacterial activity and anticancer activity were also evaluated. The LC50 values of most of the nanoparticles were found to be between 10 and 20 µg/100 µl, anticancer activity of curcumin loaded PHB nanoparticles were further confirmed by AO/PI staining and mitochondrial depolarisation assay.Inspec keywords: encapsulation, cancer, scanning electron microscopy, nanoparticles, surfactants, drugs, nanofabrication, antibacterial activity, biomedical materials, drug delivery systems, polymers, nanomedicine, Fourier transform infrared spectra, precipitation (physical chemistry), atomic force microscopy, particle sizeOther keywords: surfactant‐mediated synthesis, polyhydroxybutyrate nanoparticles, sustained drug delivery, surfactant concentrations, PHB nanoparticles, sustained curcumin delivery, drug encapsulation efficiency, anticancer activity, in vitro drug release, nanoprecipitation method, Tween 80, FTIR spectra, SEM, AFM, particle sizes, antibacterial activity, AO‐PI staining, mitochondrial depolarisation assay 相似文献
59.
A. K. Lakshminarayanan V. Balasubramanian R. Varahamoorthy S. Babu 《Metals and Materials International》2008,14(6):779-789
Control of dilution is important in hardfacing, where low dilution is typically desirable. At present, most fabrication industries
use shielded metal are welding, gas metal arc welding, gas tungsten arc welding and submerged are welding processes for hardfacing
purposes. In these processes, the percentage of the dilution level is higher, ranging between 10% and 30%. In Plasma Transferred
Arc (PTA) hardfacing, a solidified metallurgical bond between the deposit and the substrate is obtained with minimum dilution
(less than 10%). This paper highlights the application of response surface methodology to predict and optimize the percentage
of the dilution of a cobalt-based hardfaced surface produced by the PTA process. Experiments were conducted based on a fully
replicable five-factor, five-level central composite rotatable design and a mathematical model was developed using response
surface methodology. Furthermore, the response surface methodology was used to optimize the process parameters that yield
the lowest percentage of dilution. 相似文献
60.