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11.
This paper develops a framework for the consideration of internal markets as an alternative to information systems (IS) outsourcing. It is based on an assessment of the pros and cons of both outsourcing and of insourcing based on the internal markets approach. It is formulated in terms of the operational, tactical, and strategic impacts of the choice among the alternatives. The framework, and the propositions that are developed from it, should be useful both for researchers, who can use it for developing testable research hypotheses, and for practitioners, who may use it as a basis for developing a comprehensive set of criteria for the evaluation of these sourcing options. 相似文献
12.
S. Arul L. Vijayaraghavan S.K. Malhotra R. Krishnamurthy 《The International Journal of Advanced Manufacturing Technology》2006,29(7-8):655-662
Drilling trials have been carried out on glass Fibre reinforced plastics (GFRP) with plain high speed steel (HSS), TiN coated
HSS and tipped tungsten carbide drills. Most of the defects in drilling of composites are due to thrust force experienced
by the workpiece. The parametric influence on cutting force was experimentally evaluated. The experimental results show that
the defects toleranced drilling can be attained by proper selection of cutting parameters and tool material. This is substantiated
by monitoring flank wear, hole shrinkage and acoustic emission during drilling. 相似文献
13.
B. Madhusudhan Reddy Y. Venkata Mohana Reddy B. Chandra Mohan Reddy R. Meenakshi Reddy 《Journal of Natural Fibers》2020,17(5):759-768
ABSTRACTUsage of composites with natural fiber reinforcement is drastically increasing in recent times because of their low density, biodegradable nature, and low cost. However, natural fibers have certain core problems such as poor adhesion between the fiber and matrix and a relatively high degree of moisture absorption. Alkaline treatment of natural fibers is aimed at improving the adhesive strength so that effective stress transferability takes place in the composite. In the present work, Cordia-Dichotoma fibers were treated with sodium hydroxide (NaOH) and composites were prepared with different weight ratios of these fibers reinforced with epoxy. The prepared composites were tested for their tensile and flexural strengths (mechanical properties). Besides, for a comprehensive material characterization, IR spectroscopy (FT-IR), scanning electron microscope, and thermogravimetric analysis were carried out. This work investigates the influence of aforementioned NaOH treatment on thermal, mechanical, and morphological properties of the composite material. 相似文献
14.
Effects of processing and cooking on ascorbic acid content of chickpea (Cicer arietinum L) varieties
Chickpea (Cicer arietinum L) is an important source of protein in several developing countries. Two commonly grown chickpea cultivars, HPG‐17 and C‐235, were evaluated for their physicochemical characteristics such as 100‐seed weight and density. Both chickpea varieties were subjected to various processing treatments and then analysed for their ascorbic acid content. The ascorbic acid content was generally found to be higher in the C‐235 variety, but it was higher in the HPG‐17 variety after germination. Significant results were obtained for both varieties after various treatments such as pressure cooking, germination, parching and solar cooking. It was found that the ascorbic acid content in both varieties decreased after all treatments except germination. © 2001 Society of Chemical Industry 相似文献
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Buchner Daniel Schweikhart Meenakshi Behrens Sebastian Schöndorf Thomas Laskov Christine Haderlein Stefan B. 《Grundwasser》2019,24(1):51-63
Grundwasser - Eine erfolgreiche biologische In-situ-Sanierung von PCE-kontaminierten Grundwasserleitern erfordert hinreichend reduzierende Bedingungen sowie die Anwesenheit von molekularem... 相似文献
18.
Melissa J. Ruggiero Shipra Malhotra Aron W. Fenton Liskin Swint-Kruse John Karanicolas Bruno Hagenbuch 《International journal of molecular sciences》2022,23(6)
In the Na+/taurocholate cotransporting polypeptide (NTCP), the clinically relevant S267F polymorphism occurs at a “rheostat position”. That is, amino acid substitutions at this position (“S267X”) lead to a wide range of functional outcomes. This result was particularly striking because molecular models predicted the S267X side chains are buried, and thus, usually expected to be less tolerant of substitutions. To assess whether structural tolerance to buried substitutions is widespread in NTCP, here we used Rosetta to model all 19 potential substitutions at another 13 buried positions. Again, only subtle changes in the calculated stabilities and structures were predicted. Calculations were experimentally validated for 19 variants at codon 271 (“N271X”). Results showed near wildtype expression and rheostatic modulation of substrate transport, implicating N271 as a rheostat position. Notably, each N271X substitution showed a similar effect on the transport of three different substrates and thus did not alter substrate specificity. This differs from S267X, which altered both transport kinetics and specificity. As both transport and specificity may change during protein evolution, the recognition of such rheostat positions may be important for evolutionary studies. We further propose that the presence of rheostat positions is facilitated by local plasticity within the protein structure. Finally, we note that identifying rheostat positions may advance efforts to predict new biomedically relevant missense variants in NTCP and other membrane transport proteins. 相似文献
19.
Jacob Smith Rajiv Malhotra W. K. Liu Jian Cao 《The International Journal of Advanced Manufacturing Technology》2013,69(5-8):1185-1201
Single-point incremental forming (SPIF) uses one small hemispherically ended tool moving along a predefined toolpath to locally deform a completely peripherally clamped sheet of metal such that the sum total of the local deformations yields the final desired shape of the sheet. While SPIF is characterized by greater formability than conventional forming processes, it suffers from significant geometric inaccuracy. Accumulative double-sided incremental forming (ADSIF) is a substantial improvement over SPIF in which one hemispherically ended tool is used on each side of the sheet metal. The supporting tool moves synchronously with the forming tool, therefore acting as a local but mobile die. ADSIF results in considerably enhanced geometric accuracy and increased formability of the formed part as compared to SPIF. In light of the aforementioned advantages of ADSIF as compared with SPIF, an investigation of the mechanics associated with the ADSIF process, which has yet to be presented in the literature, is warranted. The present study sheds light on the differences in deformation mechanisms between SPIF and ADSIF. Finite element analyses are performed to simulate deformation in the two processes, and a detailed analysis of the deformation history is presented. It is shown that the presence of the supporting tool in ADSIF elicits substantial differences in the plastic strain, hydrostatic pressure, and shear strains as compared to SPIF. The implications of these trends on the prevalent modes of deformation in ADSIF along with possible explanations for increased formability observed in the process arediscussed. 相似文献
20.
Dodecylbenzene sulfonate (DBS)‐doped polypyrrole (PPY) conducting polymer films were electrochemically deposited onto the indium‐tin‐oxide (ITO)‐coated glass plates in aqueous medium. The enzyme cholesterol oxidase (ChOx) was immobilized on these DBS–PPY films by a physical adsorption technique. These ChOx‐immobilized DBS–PPY films were characterized by ultraviolet–visible and Fourier transform infrared spectroscopy. The enzyme activity studies indicate that ~40% of ChOx leaches out from the ChOx/DBS–PPY film. The ChOx activity in the ChOx/DBS–PPY film was assayed as a function of cholesterol concentration. The results of amperometric measurements conducted on ChOx/DBS–PPY/ITO film show linearity over the range 2–8 mM of cholesterol solution. The ChOx/DBS–PPY/ITO electrodes exhibit a response time of 30 s and are stable for ~3 months at 4 °C. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 3486–3491, 2001 相似文献