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1.
S V Bhat 《Bulletin of Materials Science》1994,17(7):1271-1285
When examined using continuous wave electron paramagnetic resonance and nuclear magnetic resonance spectrometers, the highT
c superconductors give rise to intense, low field, ‘non-resonant’ absorption signals in the superconducting state. This phenomenon
can be used as a highly sensitive, contactless technique for the detection and characterization of superconductivity even
in samples containing only minute amounts of the superconducting phase. Further, it can also be applied to the determination
of material parameters of interest such asJ
c andH
c2 in addition to being a powerful way of distinguishing between weak-link superconductivity and bulk superconductivity. The
details of these aspects are discussed. 相似文献
2.
Crystals of mixed NdLa heptamolybdates (max. size0.75×0.75×0.75 mm3) grown by silica gel technique were characterized using EDAX, IR, optical and scanning electron micrscopies.X-ray as well as electrn diffraction. The composition of the crystals was determined as (Nd1/2 La1/2 )2 Mo7O24·35H2O.The crystals exhibit varied morpholgies including square and octagonal platelets, cuboids, multifaceted crystal in coalesced and aggregated forms and spherulites.The XRD results indicate crystallinity of the grown material. Electron diffraction results suggest thermal instability of the material. IR results show the presence of peaks due to water and metal-oxygen bonds 相似文献
3.
Large signal analysis of the LCC-type parallel resonant converterusing discrete time domain modeling
A discrete time domain model for the LCC-type parallel resonant power converter has been derived. This model has been used to predict the large signal behavior of the power converter. The peak component stresses and the dynamic response of the key state variables, as obtained from the large signal analysis, using PRO-MATLAB software are plotted. SPICE results are included to verify the analytical results. Experimental results are also presented to verify the theory 相似文献
4.
监测正电源的电流时,通常使用高边检流放大器。然而,对于ISDN、电信电源,通常需要一个工作在负电源的检流放大器。本文介绍了一种采用MAX4460单电源仪表放大器设计负压检流放大器的方法。 相似文献
5.
6.
Undoped and Te-doped gallium antimonide (GaSb) layers have been grown on GaSb bulk substrates by the liquid phase epitaxial
technique from Ga-rich and Sb-rich melts. The nucleation morphology of the grown layers has been studied as a function of
growth temperature and substrate orientation. MOS structures have been fabricated on the epilayers to evaluate the native
defect content in the grown layers from theC-V characteristics. Layers grown from antimony rich melts always exhibitp-type conductivity. In contrast, a type conversion fromp- ton- was observed in layers grown from gallium rich melts below 400 C. The electron mobility of undopedn-type layers grown from Ga-rich melts and tellurium doped layers grown from Sb- and Ga-rich solutions has been evaluated.
Paper presented at the poster session of MRSI AGM VI. Kharagpur. 1995 相似文献
7.
8.
Atomic layer epitaxy or ALE has proven to be useful for the growth of epitaxial layers of high uniformity, good quality, and
well-controlled thickness. In this study, we have carried out in-situ monitoring during the atmospheric pressure ALE of CdTe on GaAs (100) substrates using spectroscopic ellipsometry (SE). The
susceptor temperature, reactant partial pressures, as well as the flow and flush duration for each precursor are crucial process
variables for ALE growth. Growth was carried out for 20–25 cycles under different sets of these process conditions during
the experiment and in-situ SE was used to verify the presence of layer-by-layer growth, which enabled the quick determination of the process window.
We observed ALE growth of CdTe at 300°C, supporting the explanation that the growth of CdTe occurs via a surface catalyzed
decomposition of the Te precursor di-isopropyltelluride (DIPTe). Investigation of ALE mode growth behavior for different susceptor
temperatures and DIPTe flush times indicated that the growth was limited by competition between desorption and reaction of
the adsorbed DIPTe species on the Cd terminated surface. 相似文献
9.
The influence of black pepper (Piper nigrum L.) and its active principle, piperine on the secretion and composition of bile was investigated in the rat. They were administered by gavage (black pepper at 250 or 500 mg and piperine at 12.5 or 25 mg/kg body wt.) or fed in the diet for 4 weeks (black pepper at 0.2 and 0.4%, piperine at 0.01 and 0.02%). The lower dose by gavage of black pepper caused an increase in bile solids while with other treatments bile secretion or dry matter in bile was not changed. Dietary feeding of black pepper caused an increase in bile flow with a concomitant decrease in bile solids -- a hydrocholagoguic effect. Cholesterol and bile acid output were not affected by black pepper or piperine at either level irrespective of the mode of administration; in contrast, the secretion of uronic acids in bile was enhanced by both levels of pepper as also of piperine indicating possible excretion of some of the components of black pepper or of piperine as glucuronides. 相似文献
10.
Realizing quality improvement through test driven development: results and experiences of four industrial teams 总被引:2,自引:2,他引:0
Nachiappan Nagappan E. Michael Maximilien Thirumalesh Bhat Laurie Williams 《Empirical Software Engineering》2008,13(3):289-302
Test-driven development (TDD) is a software development practice that has been used sporadically for decades. With this practice,
a software engineer cycles minute-by-minute between writing failing unit tests and writing implementation code to pass those
tests. Test-driven development has recently re-emerged as a critical enabling practice of agile software development methodologies.
However, little empirical evidence supports or refutes the utility of this practice in an industrial context. Case studies
were conducted with three development teams at Microsoft and one at IBM that have adopted TDD. The results of the case studies
indicate that the pre-release defect density of the four products decreased between 40% and 90% relative to similar projects
that did not use the TDD practice. Subjectively, the teams experienced a 15–35% increase in initial development time after
adopting TDD.
Nachiappan Nagappan is a researcher in the Software Reliability Research group at Microsoft Research. He received his MS and PhD from North Carolina State University in 2002 and 2005, respectively. His research interests are in software reliability, software measurement and empirical software engineering. Dr. E. Michael Maximilien (aka “max”) is a research staff member at IBM’s Almaden Research Center in San Jose, California. Prior to joining ARC, he spent ten years at IBM’s Research Triangle Park, N.C., in software development and architecture. He led various small- to medium-sized teams, designing and developing enterprise and embedded Java™ software; he is a founding member and contributor to three worldwide Java and UML industry standards. His primary research interests lie in distributed systems and software engineering, especially Web services and APIs, mashups, Web 2.0, SOA (service-oriented architecture), and Agile methods and practices. He can be reached through his Web site (maximilien.org) and blog (blog.maximilien.com). Thirumalesh Bhat is a Development Manager at Microsoft Corporation. He has worked on several versions of Windows and other commercial software systems at Microsoft. He is interested in software reliability, testing, metrics and software processes. Laurie Williams is an associate professor of computer science at North Carolina State University. She teaches software engineering and software reliability and testing. Prior to joining NCSU, she worked at IBM for nine years, including several years as a manager of a software testing department and as a project manager for a large software project. She was one of the founders of the XP Universe conference in 2001, the first US-based conference on agile software development. She is also the lead author of the Pair Programming Illuminated book and a co-editor of the Extreme Programming Perspectives book. 相似文献
Laurie WilliamsEmail: |
Nachiappan Nagappan is a researcher in the Software Reliability Research group at Microsoft Research. He received his MS and PhD from North Carolina State University in 2002 and 2005, respectively. His research interests are in software reliability, software measurement and empirical software engineering. Dr. E. Michael Maximilien (aka “max”) is a research staff member at IBM’s Almaden Research Center in San Jose, California. Prior to joining ARC, he spent ten years at IBM’s Research Triangle Park, N.C., in software development and architecture. He led various small- to medium-sized teams, designing and developing enterprise and embedded Java™ software; he is a founding member and contributor to three worldwide Java and UML industry standards. His primary research interests lie in distributed systems and software engineering, especially Web services and APIs, mashups, Web 2.0, SOA (service-oriented architecture), and Agile methods and practices. He can be reached through his Web site (maximilien.org) and blog (blog.maximilien.com). Thirumalesh Bhat is a Development Manager at Microsoft Corporation. He has worked on several versions of Windows and other commercial software systems at Microsoft. He is interested in software reliability, testing, metrics and software processes. Laurie Williams is an associate professor of computer science at North Carolina State University. She teaches software engineering and software reliability and testing. Prior to joining NCSU, she worked at IBM for nine years, including several years as a manager of a software testing department and as a project manager for a large software project. She was one of the founders of the XP Universe conference in 2001, the first US-based conference on agile software development. She is also the lead author of the Pair Programming Illuminated book and a co-editor of the Extreme Programming Perspectives book. 相似文献