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61.
S. Nagendra R. T. Haftka Z. Gürdal L. T. Watson 《Structural and Multidisciplinary Optimization》1996,11(3-4):235-243
Derivatives of buckling loads of stiffened panels with respect to ply thicknesses are easy to calculate. Consequently, such derivatives are often available in computer programs that calculate buckling loads of composite structures. These derivatives can be used to construct approximations of the dependence of the buckling load on ply thicknesses. The present work demonstrates the use of derivatives of buckling loads with respect to ply thicknesses to approximate the effects of changes in stacking sequence and ply orientations on buckling load of a laminate. Examples of unstiffened and stiffened panels are used to demonstrate the effectiveness of the proposed approximation. 相似文献
62.
Anders E. W. Jarfors Steven Tong Banghong Hu S. Nagendra Sharma Christopher Wee 《Materials and Manufacturing Processes》2003,18(4):637-641
Thin-walled hot chamber die cast parts are often used to make telephone casings and similar products having primarily requirements on weight and aesthetically satisfying surfaces. The post casting surface treatment often generates a glossy appearance. The glossy appearance makes it extremely sensitive to small-scale flaws, such as blisters, cold shuts, and cracks. Hot chamber die casting of thin-walled parts requires high filling speed and the use of lubrication because the parts have high aspect ratios. In the manufacturing of such high aspect ratio parts with a wall thickness of 0.6 mm, a new type of cold crack induced by the lubrication is observed. To some extent this defect is similar to a blister, but the characteristic bump is not formed and the actual crack is formed by thermal contraction along the high aspect ratio areas. 相似文献
63.
Abstract A comprehensive investigation of the solubility and mass transfer coefficient enhancement of benzene through hydrotropy has been undertaken. The solubility and mass transfer coefficient studies were carried out using hydrotropes such as citric acid, urea, nicotinamide, and sodium salicylate under a wide range of hydrotrope concentrations (0 to 3.0 mol/L) and different system temperatures (303 to 333 K). The effectiveness of hydrotropes was measured in terms of Setschenow constant KS and reported for all hydrotropes used in this study. 相似文献
64.
Free (FP) and bound phenolics (BP) were extracted from freeze dried (FD), oven dried (OD), as well as boiling treated (BT) Pleurotus eryngii samples. Free, bound, total phenolics were quantified using Folin–Ciocalteau assay. Qualitative and quantitative analysis of phenolic compounds were carried out using high‐performance liquid chromatography (HPLC) coupled with diode array detector (DAD), and a total of 8 phenolic compounds were detected. Free phenolic contents followed the order: Freeze‐dried free phenolics (FDFP) > Oven‐dried free phenolics (ODFP) > Boiling‐treated free phenolics (BTFP), and ranged from 95.42 (BTFP) to 442.50 (ODPF) μg gallic acid equivalents (GAE)/g dry weight (DW). Bound and total phenolic contents followed the order: FD > OD > BT, and ranged from 218.33 (BTBP) to 774.17 (FDBP) and 313.75 (BT total phenolics) to 1090.42 (FD total phenolics) μg GAE/g DW. Bound phenolics contributed 49.76% (OD), 69.59% (BT), and 71% (FD) of the total phenolic contents. All free and bound phenolic extracts were investigated for their antioxidant activities by 3 different assays, 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) radical scavenging activity, reducing power, and superoxide anion radical scavenging activity. FDFP showed strongest DPPH radical scavenging activity (IC50 at 32.61 μg/mL), ODFP showed strongest reducing power (IC50 at 26.31 μg/mL), and BTBP showed strongest superoxide anion radical scavenging activity (IC50 at 14.07 μg/mL). 相似文献
65.
Guoxiang Jiang K. Nagendra Prasad Yueming Jiang Bao Yang Yongxia Jia Jian Sun 《Innovative Food Science and Emerging Technologies》2009,10(4):638-642
Two alkali-soluble polysaccharide fractions (ASPs I and II) were extracted from longan fruit pericarp in this work. The results of chemical composition indicated that ASP I and II fractions comprised mainly of polysaccharides, proteins and lignins. Four monosaccharides, namely Xyl, Ara, Glc and Gal, were identified for both ASPs I and II. Xyl was the dominant monosaccharide in the two alkali-soluble polysaccharides with relative molar percentages of >60%. It constructed the backbone in combination with Ara for both ASPs I and II. The analysis of glycosidic linkage indicated that Xyl had two linkages,→3)-Xyl-(1→ and →3, 4)-Xyl-(1→. The substitution at C-4 position indicated that Xyl was of pyranose structure. The infrared spectra of ASPs I and II showed the characteristic bands at approximate 897 cm− 1 which indicated the β-linkage configuration of Xyl.
Industrial relevance
Hemicellulose has been suggested as an important polysaccharide with good pharmaceutical properties, including immune modulation and anti-cardiovascular diseases. In this work, alkali-soluble polysaccharides were extracted from longan fruit pericarp and fractionated. The structural characteristics were identified by gas chromatography/mass spectrometry and infrared spectrophotometry. The results will be helpful for application of hemicellulose in functional food industry. 相似文献66.
Yue Ying Ong Soon Wee Ho Vasarla Nagendra Sekhar Samuel Lim Yak Long Leong Ching Wai Jimmy Ong Xiaowu Zhang John H. Lau David Yeo Zhang Yanfeng Dong Kyun Sohn 《Microelectronics Reliability》2010,50(7):986-994
This paper reports the design, assembly and reliability assessment of 21 × 21 mm2 Cu/low-k flip chip (65 nm node) with 150 μm bump pitch and high bump density. To reduce the stress from the solder bump pad to low-k layers, Metal Redistribution Layer (RDL) and Polymer Encapsulated Dicing Lane (PEDL) are applied to the Cu/low-k wafer. Lead-free Sn2.5Ag, high-lead Pb5Sn and Cu-post/Sn37Pb bumps are evaluated as the first-level interconnects. It is found that the flip chip assembly of high-lead bumped test vehicle requires the right choice of flux and good alignment between the high-lead solder bumps and substrate pre-solder alloy to ensure proper solder bump and substrate pre-solder alloy wetting. Joint Electron Device Engineering Council (JEDEC) standard reliability is performed on the test vehicle with different first-level interconnects, underfill materials and PEDL.By integrating PEDL to the Cu/low-k chip, the reliability performance of the flip chip package has been improved by almost two times. This paper has demonstrated Moisture Sensitivity Test-Level 2 (MST-L2) qualified large die and fine-pitch Cu/low-k flip chip package. The presented results are significant for the development of flip chip packaging technologies for future advanced Cu/low-k generations. 相似文献
67.
Numerical exploration of thermal radiation and Biot number effects on the flow of a non‐Newtonian MHD Williamson fluid over a vertical convective surface 下载免费PDF全文
Chota Hyder Amanulla Nallagundla Nagendra Annasagaram Subba Rao Osman Anwar Bég Ali Kadir 《亚洲传热研究》2018,47(2):286-304
A theoretical and computational study of the magnetohydrodynamic flow and free convection heat transfer in an electroconductive polymer on the external surface of a vertical plate under radial magnetic field is presented. The Biot number effects are considered at the vertical plate surface via modified boundary conditions. The Williamson viscoelastic model is employed which is representative of certain industrial polymers. The nondimensional, transformed boundary layer equations for momentum and energy are solved with the second‐order accurate implicit Keller box finite difference method under appropriate boundary conditions. Validation of the numerical solutions is achieved via benchmarking with earlier published results. The influence of Weissenberg number (ratio of the relaxation time of the fluid and time scale of the flow), magnetic body force parameter, stream‐wise variable, and Prandtl number on thermo fluid characteristics are studied graphically and via tables. A weak elevation in temperature accompanies increasing Weissenberg number, whereas a significant acceleration in the flow is computed near the vertical plate surface with increasing Weissenberg number. Nusselt number is reduced with increasing Weissenberg number. Skin friction and Nusselt number are both reduced with increasing magnetic field effect. The model is relevant to the simulation of magnetic polymer materials processing. 相似文献
68.
69.
Lactobacillus plantarum WCFS1 Fermentation Differentially Affects Antioxidant Capacity and Polyphenol Content in Mung bean (Vigna radiata) and Soya Bean (Glycine max) Milks 下载免费PDF全文
70.
Sakthivel Muniyan Nagendra K. Chaturvedi Jennifer G. Dwyer Chad A. LaGrange William G. Chaney Ming-Fong Lin 《International journal of molecular sciences》2013,14(5):10438-10464
Human prostatic acid phosphatase (PAcP) is a 100 kDa glycoprotein composed of two subunits. Recent advances demonstrate that cellular PAcP (cPAcP) functions as a protein tyrosine phosphatase by dephosphorylating ErbB-2/Neu/HER-2 at the phosphotyrosine residues in prostate cancer (PCa) cells, which results in reduced tumorigenicity. Further, the interaction of cPAcP and ErbB-2 regulates androgen sensitivity of PCa cells. Knockdown of cPAcP expression allows androgen-sensitive PCa cells to develop the castration-resistant phenotype, where cells proliferate under an androgen-reduced condition. Thus, cPAcP has a significant influence on PCa cell growth. Interestingly, promoter analysis suggests that PAcP expression can be regulated by NF-κB, via a novel binding sequence in an androgen-independent manner. Further understanding of PAcP function and regulation of expression will have a significant impact on understanding PCa progression and therapy. 相似文献