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排序方式: 共有273条查询结果,搜索用时 15 毫秒
11.
C. Sasikumar K. Balamurugan S. Rajendran S. Naveenkumar 《Materials and Manufacturing Processes》2016,31(6):701-706
Among all alternate fuel sources available, the biodiesel of Jatropha curcas appears to be a potential fuel as it widely exists in Asia. The Jatropha methyl ester (JME) is produced by transesterification process. In the transesterification process, alkyl group of ester exchanges with that of an alcohol. This work focuses on optimizing various parameters like quantities of methanol, KOH, and stirrer speed, which influence high JME yield. Based on L9 orthogonal array, experiments are conducted by using Taguchi technique. All the nine combinations of L9 orthogonal array are experimentally done for extraction of JME, and then it is used for analysis in Taguchi technique. The analysis of maximum yield is done on the basis of “larger is better” signal to noise ratio (S/N ratio). The best combination in the L9 orthogonal array is found to be methanol (110 ml), KOH (1.306 gm), and stirrer speed (1200 rpm). The influence of methanol, KOH, and stirrer speed on the yield is found by analysis of variance (ANOVA). Based on the results of ANOVA, it is found that the influence of methanol, KOH, and stirrer speed on the yield are obtained as 70.10%, 20.35%, and 5.78%, respectively. 相似文献
12.
Tulyaganov DU Agathopoulos S Valerio P Balamurugan A Saranti A Karakassides MA Ferreira JM 《Journal of materials science. Materials in medicine》2011,22(2):217-227
New compositions of bioactive glasses are proposed in the CaO–MgO–SiO2–Na2O–P2O5–CaF2 system. Mineralization tests with immersion of the investigated glasses in simulated body fluid (SBF) at 37°C showed that
the glasses favour the surface formation of hydroxyapatite (HA) from the early stages of the experiments. In the case of daily
renewable SBF, monetite (CaHPO4) formation competed with the formation of HA. The influence of structural features of the glasses on their mineralization
(bioactivity) performance is discussed. Preliminary in vitro experiments with osteoblasts’ cell-cultures showed that the glasses
are biocompatible and there is no evidence of toxicity. Sintering and devitrification studies of glass powder compacts were
also performed. Glass-ceramics with attractive properties were obtained after heat treatment of the glasses at relatively
low temperatures (up to 850°C). 相似文献
13.
Dr. Balamurugan Dhayalan Dr. Ann Fitzpatrick Dr. Kalyaneswar Mandal Dr. Jonathan Whittaker Prof. Dr. Michael A. Weiss Prof. Dr. Andrei Tokmakoff Prof. Dr. Stephen B. H. Kent 《Chembiochem : a European journal of chemical biology》2016,17(5):415-420
Isotope‐edited two‐dimensional Fourier transform infrared spectroscopy (2 D FTIR) can potentially provide a unique probe of protein structure and dynamics. However, general methods for the site‐specific incorporation of stable 13C=18O labels into the polypeptide backbone of the protein molecule have not yet been established. Here we describe, as a prototype for the incorporation of specific arrays of isotope labels, the total chemical synthesis—via a key ester insulin intermediate—of 97 % enriched [(1‐13C=18O)PheB24] human insulin: stable‐isotope labeled at a single backbone amide carbonyl. The amino acid sequence as well as the positions of the disulfide bonds and the correctly folded structure were unambiguously confirmed by the X‐ray crystal structure of the synthetic protein molecule. In vitro assays of the isotope labeled [(1‐13C=18O)PheB24] human insulin showed that it had full insulin receptor binding activity. Linear and 2 D IR spectra revealed a distinct red‐shifted amide I carbonyl band peak at 1595 cm?1 resulting from the (1‐13C=18O)PheB24 backbone label. This work illustrates the utility of chemical synthesis to enable the application of advanced physical methods for the elucidation of the molecular basis of protein function. 相似文献
14.
Unidirectional <100> potassium dihydrogen orthophosphate (KDP) single crystals were grown for the first time by Sankaranarayanan-Ramasamy (SR) method. The <100> oriented seed crystals were mounted at the bottom of the glass ampoules and the crystal of 15 mm diameter, 65 mm height were grown by SR method. The grown crystals were characterized by high-resolution X-ray diffraction (HRXRD), etching studies. The HRXRD analysis indicates that the crystalline perfection is excellent without having any very low angle internal structural grain boundaries. Dislocation density is less in SR grown KDP compared to conventional method grown KDP. 相似文献
15.
A rigorous analysis of a broad-wall slot coupler between two crossed rectangular waveguides is presented. The slot is longitudinal and offset from the center line in the main guide and is centered transverse in the branch guide. Integral equations are developed, taking into account finite wall thickness. The integral equations are then solved for the aperture electric field. Coupling slot characteristics are obtained, including the resonant length and dominant mode scattering. Numerical results for resonant length and scattering parameters are presented over a range of offsets, waveguide dimensions, and frequencies 相似文献
16.
Silicon - We have studied the mc-Si wafers with different (hkl) planes. Initially, the wafer was chemically etched by the KOH (20wt%) and IPA (2%) in the Millipore water at 60 °C for... 相似文献
17.
S. Appavu alias Balamurugan Ramasamy Rajaram 《Expert systems with applications》2009,36(10):12113-12119
This paper deals with some improvements to rule induction algorithms in order to resolve the tie that appear in special cases during the rule generation procedure for specific training data sets. These improvements are demonstrated by experimental results on various data sets. The tie occurs in decision tree induction algorithm when the class prediction at a leaf node cannot be determined by majority voting. When there is a conflict in the leaf node, we need to find the source and the solution to the problem. In this paper, we propose to calculate the Influence factor for each attribute and an update procedure to the decision tree has been suggested to deal with the problem and provide subsequent rectification steps. 相似文献
18.
S. Balamurugan 《Chemical engineering science》2008,63(3):721-731
Ejectors are gas-liquid contactors that are reported to provide higher mass transfer rates than conventional contactors. Detailed experiments were performed and computational fluid dynamics (CFD) modeling studies were undertaken to understand the hydrodynamic characteristics of the ejector geometry. The CFD model provides a basis for quantifying the effects of operating conditions on the ejector performance. CFD studies shows that there is an optimum ratio of nozzle area to throat area (area ratio), at which the liquid entrainment rate is the highest. This can lead to substantial economic benefit in the industrial practice. The liquid entrainment rate correlates with pressure difference between the water surface in the suction chamber and the throat exit for a wide variety of ejector geometries and operating conditions. 相似文献
19.
S. Theodore Chandr N. B. Balamurugan M. Bhuvaneswari N. Anbuselvan N. Mohankumar 《半导体学报》2015,36(6):064003-6
A compact model is proposed to derive the charge density of the AlInSb/InSb HEMT devices by considering the variation of Fermi level, the first subband, the second subband and sheet carrier charge density with applied gate voltage. The proposed model considers the Fermi level dependence of charge density and vice versa. The analytical results generated by the proposed model are compared and they agree well with the experimental results. The developed model can be used to implement a physics based compact model for an InSb HEMT device in SPICE applications. 相似文献
20.
Silicon - In this study, we present an ambipolar conduction and RF stability performance for a Germanium Source Dual Halo Dual Dielectric Triple Material Surrounding Gate Tunnel FET... 相似文献