Surface integrity when machining age hardened Inconel 718 with coated carbide cutting tools

Considerable attention has been given to the use of ceramic cutting tools for improving productivity in the machining of heat resistant super alloys (HRSA). However, because of their negative influence on the surface integrity, ceramic tools are generally avoided particularly for finishing applications. As a result the main high end manufacturers are more or less dependent on carbide cutting tools for finishing operations. Still the improper use of carbide cutting tools can also result in poor surface integrity. The objective of this investigation is to develop a set of guidelines, which will assist the selection of the appropriate cutting tools and conditions for generating favorable compressive residual stresses. This paper specifically deals with residual stresses and surface finish components of surface integrity when machining (facing) age hardened Inconel 718 using two grades of coated carbide cutting tools specifically developed for machining HRSAs. The cutting conditions were obtained from investigations based on optimum tool performance. The effect of insert shape, cutting edge preparation, type and nose radius on both residual stresses and surface finish was studied at this optimum cutting condition. This investigation, suggested that coated carbide cutting tool inserts of round shape, chamfered cutting edge preparation, negative type and small nose radius (0.8 mm) and coolant will generate primarily compressive residual stresses.     

A small country in a world of big science a preliminary bibliometric study of science in Singapore

An analysis of 258 papers published from Singapore and covered inScience Citation Index (SCI) 1979 and 1980 indicates that (1) much of R&D in Singapore pertains to medical research, (2) almost all the papers are published in English language periodicals published from the western world, (3) nearly two-thirds of Singapore's publication output is accounted for by the University of Singapore, and (4) by and large papers from Singapore are rarely cited, even if many of them have appeared in journals having impact factor greater than one.     

A novel prognosis and segmentation of necrosis (dead cells) in contrast enhanced T1-weighted glioblastoma tumor with automatic contextual clustering

In recent years, mortality rate with high-grade tumor has been increased significantly especially with glioblastoma (GBM) brain tumor while compared to other malignant brain tumor. Here, the amount of dead cells accommodated with the tumor tissue in GBM brain tumor play a vital task and necessitate an earlier diagnosis of malignancy with the GBM tumor. It inspires to implement new automatic diagnosis system which detects the dead cells and tumor tissue with the GBM brain tumor, such that the survival rate of the diseased can easily be prognosis by the Radiologist and Neurosurgeon. The main objective of this article is to detect the amount of dead cells with respect to tumor tissue associated with the GBM brain tumor which desires the impact factor of the brain tumor. In this framework, initially, the new contrast enhancement modality is incorporated to enhance the gray information over the dead cells and the tumor tissue with the T1-weighted MRI GBM brain tumor. In this enhancement, the edges of the tumor cells and its dead cells are magnified efficiently. As the noises and outliers with MR image is unpredictable and it experiences the variable amount of noises over the local window, the contextual information over each pixel of the image is adaptively modified with respect to the amount of noise over local window using adaptive contextual clustering. The performance evaluation of the framework is investigated which exhibits the overwhelming result compared to conventional detection techniques.     

Solid-state production of esterase using fish processing wastes by Bacillus altitudinis AP-MSU

The bacterium Bacillus altitudinis AP-MSU, able to produce esterase was isolated from the gut of marine fish Sardinella longiceps. The esterase production was investigated in solid-state fermentation experiment using various fish processing waste meal. Among the tested fish processing wastes, red grouper waste emerged as the best source for higher esterase production. The suitable surfactant and triglyceride identified to increase the lipase production was neem oil. Effect of individual carbon and nitrogen sources supplementation on esterase production revealed that fructose and peptone aided the higher esterase production than the other tested carbon and nitrogen sources. The suitable concentration of sodium chloride for higher esterase production was at 5%. Effect of surfactants and trace elements on esterase production showed that Tween 20 and zinc sulphate, respectively produced maximum amount of esterase. The effect of physical parameters on lipase production revealed that 50 °C temperature and pH 7–8 were optimum for higher esterase production. Statistical optimization with Plackett–Burman design showed that neem oil, NaCl and fructose were found to be the most predictive factors for esterase production by this strain.     

Evaluation of Antioxidant Activity,and Nutritional and Chemical Composition of Ficus amplissima Smith Fruit

The present study was evaluated using the following in vitro antioxidant methods: 2,2′-azinobis (3-ethyl-benzothiozoline)-6-sulfonic acid disodium salt, phosphomolybdenum, ferric reducing antioxidant power, metal ion chelating activity, super oxide anion radical scavenging, hydrogen peroxide, and hydroxyl radical. Among these assays, acetone extract showed maximum free radical scavenging activity in 2,2′-azinobis (3-ethyl-benzothiozoline)-6-sulfonic acid disodium salt, phosphomolybdenum, metal ion chelating, superoxide anion, hydrogen peroxide, and hydroxyl radical assays. Moreover, the physiochemical, nutritional, and anti-nutritional parameters were analyzed. Its qualitative and quantitative composition was studied by gas chromatography-mass spectroscopy and out of 27 peaks, 27 compounds were identified. These compounds have the property of antioxidant, antimicrobial, and anti-inflammatory activity.     

PREDICTION OF JAPANESE ENCEPHALITIS VECTORS IN KURNOOL DISTRICT OF ANDHRA PRADESH,INDIA BY USING BAYESIAN NETWORK

Japanese encephalitis (JE), a complex viral disease transmitted by mosquitoes. Determination of vector (mosquito) density is a prerequisite for devising effective control measures against this disease. Bayesian network is a widely used tool that has recently found application in the epidemiological surveillance studies. This article describes the application of Bayesian network tool to predict the Japanese encephalitis vector density using the longitudinal data collected from the Kurnool district of Andhra Pradesh, India, from 2001 to 2006. The entomological parameter from the study area indicates that various contributing factors are responsible for the prevalence of these vectors, making it difficult to estimate the importance of any particular parameter contributing to the increase of vector density. The application of this approach resulted in 73.12% to 95.12% accuracy compared to the test data with the corrected data.     

Synthesis and properties of manganese-doped barium titanate

An oxalate route for the production of BaTiO₃ has been modified to incorporate Mn (upto 2%) as a dopant and the reaction sequence has been studied. The resulting Mn-doped BaTiO₃ exhibits a dielectric constant with an increasing insensitivity to temperature and applied a.c. field as the Mn content is increased. These samples possess a high electrical resistivity even after treatment in hydrogen at 1100°C and are therefore suitable as dielectric for multilayer capacitors with base metal electrodes.     

Water-soluble polymers. I. Synthesis of N-succinimido (N) thiocarbonyl acrylamide and its polymerization: Grafting of this monomer and acrylamide onto poly(vinyl alcohol)

A new monomer, N-succinimido (N) thiocarbonyl acrylamide is formed when succinic anhydride, thiourea, and acryloyl chloride are condensed in mole proportions at low temperatures. The monomer is polymerized and graft copolymerized onto poly(vinyl alcohol) using a potassium bromate-thiourea redox system. Acrylamide is also similarly grafted to poly(vinyl alcohol) using the same initiator system. Grafting efficiencies of the monomers are determined from the elemental analyses data of the graft copolymers. Thermal behavior of the polymers are derived from the DSC thermograms of the polymers. © 1993 John Wiley & Sons, Inc.     

Integration of Ceramics Research with the Development of a Microsystem

Rapid implementation of new materials into engineering systems may require a paradigm shift in our approach to materials research. One option is to obtain fundamental material properties from experimental systems that can also serve as devices. This concept is applied to the measurement of Young's modulus of a novel ceramic, a polymer-derived silicon carbonitride (SiCN), directly from the performance of a microelectromechanical system (MEMS) device. The device is an electrostatic actuator. The flexure resistance of the arms of the actuator is measured and analyzed for the elastic modulus of SiCN. The comparison between theory and experiment yields a value for Young's modulus in the range 130–155 GPa.