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101.
Silicon - In this paper, a compact 2D analytical modelling of surface potential and simulation of Si-Ge hetero-junction Dual Material Gate Vertical t-shape T-FET is presented. In the proposed... 相似文献
102.
Journal of Applied Electrochemistry - Newly synthesized polyurethane (PU)–polydopamine (Pda)/CeO2 (cerium oxide) nanocomposite-coated mild steel was investigated for its corrosion protection... 相似文献
103.
Gill Raj; Verma Chandra; Wallach Brenda; Urso Birgitte; Pitts Jim; Wollmer Axel; De Meyts Pierre; Wood Steve 《Protein engineering, design & selection : PEDS》1999,12(4):297-303
Insulin-like growth factor-1 (IGF-1) is a serum protein whichunexpectedly folds to yield two stable tertiary structures withdifferent disulphide connectivities; native IGF-1 [1861,648,4752]and IGF-1 swap [1861,647, 4852]. Here we demonstratein detail the biological properties of recombinant human nativeIGF-1 and IGF-1 swap secreted from Saccharomyces cerevisiae.IGF-1 swap had a ~30 fold loss in affinity for the IGF-1 receptoroverexpressed on BHK cells compared with native IGF-1.The parallelincrease in dose required to induce negative cooperativity togetherwith the parallel loss in mitogenicity in NIH 3T3 cells impliesthat disruption of the IGF-1 receptor binding interaction ratherthan restriction of a post-binding conformational change isresponsible for the reduction in biological activity of IGF-1swap. Interestingly, the affinity of IGF-1 swap for the insulinreceptor was ~200 fold lower than that of native IGF-1 indicatingthat the binding surface complementary to the insulin receptor(or the ability to attain it) is disturbed to a greater extentthan that to the IGF-1 receptor. A 1.0 ns high-temperature moleculardynamics study of the local energy landscape of IGF-1 swap resultedin uncoiling of the first A-region -helix and a rearrangementin the relative orientation of the A- and B-regions. The modelof IGF-1 swap is structurally homologous to the NMR structureof insulin swap and CD spectra consistent with the model arepresented. However, in the model of IGF-1 swap the C-regionhas filled the space where the first A-region -helix has uncoiledand this may be hindering interaction of Val44 with the secondinsulin receptor binding pocket. 相似文献
104.
Raj Kumar Singh Sunil Kumar Sinha A. Rama Rao 《Nuclear Engineering and Design》2009,239(10):1760-1767
The primary function of the shut down system in a nuclear reactor is to terminate any reactivity transient occurring in the core during its entire design life. Normally there is more than one system, which are independent and diverse in its mode of operation. They consist of quick acting mechanisms like dropping of safety rods by gravity, poison injection, etc. Typically in liquid poison injection system wherein high flow velocities are involved, there is significant fluid structure interaction associated with cyclic shock transients in the system. One such phenomenon has been captured and analyzed to understand the dynamics involved in the loop. The trends of loop pressure and vibration indicated presence of more than two pressure transients after complete injection of poison. The first transient arrived after 1.44 s and the second after 0.75 s. The reverse pressure pulses that manifested in the loop as a result of fast injection of fluid has been mathematically characterized by solving basic fluid balance equations. Possibility of ball lifting due to momentum pulse is also discussed. 相似文献
105.
L. Satyanarayan Anish Kumar T. Jayakumar C. V. Krishnamurthy Krishnan Balasubramaniam Baldev Raj 《Journal of Nondestructive Evaluation》2009,28(3-4):111-124
New techniques developed using the array transducer, to image and size the bottom-surface and near-through-wall crack-like defects in thick carbon steel components are discussed. Three studies are reported here including (a) Optimal beam steering angle for focused and unfocused inspection using phased array method for bottom-surface crack sizing. (b) A front wall correction algorithm for sizing of near-through-wall crack-like defects. (c) A small aperture technique for sizing of near-through-wall crack-like defects. A Finite Difference Time Domain (FDTD) based simulation was used to study and verify the experimental observations. The application of time domain scheme relative arrival time technique (RATT), to measure the size of the near-through wall crack-like defects for the leak before break (LBB) criterion, was also investigated and found to be insufficient. A conventional SAFT algorithm was used for improving the sizing using the small aperture technique. 相似文献
106.
P. Shankar P. Palanichamy T. Jayakumar Baldev Raj S. Ranganathan 《Metallurgical and Materials Transactions A》2001,32(12):2959-2968
The presence of even dilute concentrations of nitrogen (0.08 mass pct) is found to have a strong influence on the microstructure
of a nuclear grade 316LN austenitic stainless steel, thermally aged at 1123 K. High-resolution transmission electron microscopy
(TEM) evidence of pre-precipitation reactions involving formation of Cr-N rich clusters prior to Cr2N precipitation has been presented. A tendency for cellular precipitation has been observed on continued aging above 500 hours.
Beyond 1000 hours, chi precipitates are the most frequently seen phase. The observed microstructural variations correlate
well with ultrasonic velocity and attenuation measurements. The present study reveals that nitrogen in solid solution decreases
all the elastic constants, namely longitudinal modulus, elastic modulus, shear modulus, and bulk modulus in this steel but
has a negligible effect on Poisson’s ratio. The stages associated with the precipitation of intragranular coherent Cr2N are, however, associated with an increase in all the elastic constants including Poisson’s ratio. 相似文献
107.
108.
A bibliography on research work related to nullors and their applications in circuit analysis, synthesis and design, covering the period 1961–2000, is given. 相似文献
109.
This article presents a novel methodology for designing double‐ridged waveguides by numerically optimizing their geometric shape such that they sustain the two prescribed lowest order modes. The field solution to the problem is obtained by using the finite element method. The performance of the microgenetic algorithm and the quasi‐Newton methods is studied for carrying out geometry optimization. This generalized formulation is capable of handling inhomogeneous material fillings in the guide, and computational results are presented to demonstrate the versatility of the proposed technique. © 2002 Wiley Periodicals, Inc. Int J RF and Microwave CAE 12, 530–539, 2002. Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mmce.10053 相似文献
110.
This paper examines the project sponsoring pattern and the outcome of extramural R&D with respect to the projects sponsored
by country's eleven central agencies during the Seventh Five-Year Plan period. The outcome considered are: contribution of
R&D support to development of R&D facilities at the recipient institutions, creation of employment through project posts,
development of new technologies, quantum and quality of research publications and generation of doctoral thesis. The paper
concludes that sponsored R&D has largely remained one-way flow of funds to a preferred set of institutions (as perceived by
each sponsoring agency) and the outcome of the R&D have also remained unexamined by the respective funding agencies. The paper
advocates development of a monitoring system which would help in enhancing the utilisation of sponsored R&D and its overall
impact on science, society and economy. 相似文献