排序方式: 共有29条查询结果,搜索用时 31 毫秒
1.
Laxman Singh Ravikant Sharma Narayan Singh Atendra Kumar Dev K Mahato Youngil Lee Mikhael Bechelany KD Mandal 《Progress in Crystal Growth and Characterization of Materials》2021,67(4):100542
This review paper covers the low temperature wet growth of nano-engineered particles of ZnO-based mixed metal oxides, their growth mechanism, and characterization using X-ray diffraction, SEM, TEM and IR, UV–visible, and XPS spectral techniques. Main focus of this article is centered on low temperature semi-wet methods of synthesis that are suitable for large scale production of zinc oxide-based systems mixed with iron oxide, copper oxide, nickel oxide and cobalt oxide. These mixed metal oxides have broad industrial applications as catalyst, semiconductors, adsorbents, superconductors, electro-ceramics, and antifungal agents in addition to extensive applications in medicines. This paper discusses the low-cost and environment friendly synthesis of these mixed metal oxides, measurement of properties and applicability of these materials systems. 相似文献
2.
Edward J. Kramer Heider G. Krenz Dieter G. Ast 《Journal of Polymer Science.Polymer Physics》1978,16(2):349-366
Methanol crazes are grown from sharp cracks in poly(methyl methacrylate) (PMMA). The craze thickness profile is measured using a replica technique after the craze opening displacement profile of the growing craze has been measured with holographic interferometry. The craze strain profile is then computed from these data. The craze surface stress profile is determined by two methods: (1) from the uniaxial strain profile of regions adjacent to the craze as measured from the fringe spacing on the reconstructed hologram and (2) from the craze opening displacement profile using the Fourier transform method of Sneddon. From the surface stress and craze-strain profiles a true stress-strain curve for the craze fibrils has been constructed. The extrapolated fibril yield stress is in good agreement with the yield stress of bulk PMMA plasticized with methanol indicating that surface tension effects do not contribute importantly to craze fibril mechanical properties at room temperature. The craze strain increases from 0.4 near the craze tip to 1.4 near the craze base implying that methanol crazes in PMMA thicken by further straining of the existing craze fibrils and not by drawing new material into the craze from the craze surfaces. The primordial craze thickness, i.e., the original thickness of polymer which fibrillates to form the craze fibrils, is approximately 1 μm and is constant over most of the craze length. This thickness may be determined by diffusion of methanol normal to the craze surfaces in a process zone just behind the craze tip. 相似文献
3.
T. Eichten H. Deden F.J. Hasert W. Krenz J. Von Krogh D. Lanske J. Morfin H. Weerts G. Bertrand-Coremans J. Sacton W. Van Doninck P. Vilain D.C. Cundy D. Haidt M. Jaffre G. Kalbfleisch S. Natali P. Musset J.L. Pinfold 《Physics letters. [Part B]》1973,46(2):281-284
The total cross-sections for -nucleon scattering have been measured. A test has been made of the muon number conservation law. A limit of 2.4 GeV is found the mass of the “Georgi-Glashow type” heavy lepton 相似文献
4.
H. Deden F.J. Hasert W. Krenz D. Lanske J. Morfin M. Pohl K. Schultze L. Welch G. Bertrand-Coremans H. Mulkens J. Sacton W. Van Doninck H. Burmeister I. Danilchenko D. Haidt P. Jobin C. Matteuzzi P. Musset A.J. Segar 《Physics letters. [Part B]》1977,67(4):474-478
New results are presented of an analysis of pictures taken during an exposure of Gargamelle to the CERN ν beam in 1975. In addition to three νμ+N→μ?+e++V0+ hadrons events previously reported, an excess is found of events of the type νμ+N→μ?+e++ hadrons without V0. An analysis of strange particle production in charged current events suggests a possible violation of the ΔS=ΔQ rule. Interpreted in terms of charm production, the data permit an estimate of branching ratios and production rate of charmed particles. A limit is also placed on charmed particle production by neutral currents. 相似文献
5.
We consider a collapsing spherically symmetric inhomogeneous dust cloud in higher dimensional space-time. We show that the
central singularity of collapse can be a strong curvature or a weak curvature naked singularity depending on the initial density
distribution. 相似文献
6.
Nadine S Simons-Weidenmaier Maruschka Weber Claudia F Plappert Peter KD Pilz Susanne Schmid 《BMC neuroscience》2006,7(1):38
Background
Short-term habituation of the startle response represents an elementary form of learning in mammals. The underlying mechanism is located within the primary startle pathway, presumably at sensory synapses on giant neurons in the caudal pontine reticular nucleus (PnC). Short trains of action potentials in sensory afferent fibers induce depression of synaptic responses in PnC giant neurons, a phenomenon that has been proposed to be the cellular correlate for short-term habituation. We address here the question whether both this synaptic depression and the short-term habituation of the startle response are localized at the presynaptic terminals of sensory afferents. If this is confirmed, it would imply that these processes take place prior to multimodal signal integration, rather than occurring at postsynaptic sites on PnC giant neurons that directly drive motor neurons. 相似文献7.
Brian A. Slovick Peter M. Krenz Guy Zummo Glenn D. Boreman 《Infrared Physics & Technology》2010,53(2):89-93
Infrared dipole-coupled bolometers receive radiation more efficiently when illuminated through a high permittivity, antireflection (AR) coated, hemispherical immersion lens. To maintain the enhanced responsivity for all illumination angles, the AR coating must be uniform over the hemispherical surface. An evaporation method for depositing a uniform AR coating on the hemispherical surface is presented. The lens is tilted relative to the source, which can be either electron-beam or thermal, and rotated throughout the deposition. Evaporation at an angle of 70° yields a uniform film with less than 10% thickness variation over a 120° full angle of the hemispherical surface. A theoretical model is developed and compared to profilometer measurements. In all cases, there is general agreement between theory and measurement. A single dipole is fabricated onto the flat surface of an AR-coated germanium immersion lens and the responsivity is measured for both substrate-side and air-side illumination. With a zinc sulfide (ZnS) single-layer AR coating, substrate-side illumination yields a broadside antenna response 49 ± 2.7 times greater than air-side illumination. 相似文献
8.
J. Blietschau H. Deden F.J. Hasert W. Krenz J. Morfin K. Schultze L. Welch G. Bertrand-Coremans M. Dewitt H. Mulkens J. Sacton W. Van Doninck H. Wachsmuth P. Musset J.B. Pattison F. Romano K. Myklebost I. Danilchenko J. Pinfold 《Physics letters. [Part B]》1978,73(2):232-234
An upper limit of 3 × 10?42Eν cm2 per electron, at 90% confidence level, has been obtained for the cross section of the process νμ + e? → νμ + e?, interpreted in the usual V-A framework, for an electron recoil energy larger than 0.3 GeV. This estimate is based on the observation of one candidate event in exposures of Gargamelle to the CERN PS neutrino beam. 相似文献
9.
F.J. Hasert S. Kabe W. Krenz J. Von Krogh D. Lanske J. Morfin K. Schultze H. Weerts G.H. Bertrand-Coremans J. Sacton W. Van Doninck P. Vilain U. Camerini D.C. Cundy R. Baldi I. Danilchenko W.F. Fry D. Haidt W.G. Scott 《Physics letters. [Part B]》1973,46(1):138-140
Events induced by neutral particles and producing hadrons, but no muon or electron, have been observed in the CERN neutrino experiment. These events behave as expected if they arise from neutral current induced processes. The rates relative to the corresponding charged current processes are evaluated. 相似文献
10.
Favre C Boutou V Hill SC Zimmer W Krenz M Lambrecht H Yu J Chang RK Woeste L Wolf JP 《Physical review letters》2002,89(3):035002
We report the first observation of white-light emission from femtosecond laser-induced plasma in a water droplet. Such emission is not observed with water in a cell. The microdroplet acts as a lens, focusing the incident light to nanosized regions within itself and directing the emission from these regions primarily back toward the laser source. This focusing increases the intensity so that multiphoton ionization generates plasma and causes it to reach the critical density during the initial part of the pulse, enabling the rest of the pulse to heat the plasma enough to emit in the visible. 相似文献