排序方式: 共有36条查询结果,搜索用时 31 毫秒
1.
E. Matsinos J. Guy E. Simopoulou W. Venus P. Allport M. Berggren M. Calicchio T. Coghen A. M. Cooper-Sarkar O. Erriquez N. Giannakopoulos G. T. Jones P. Marage M. M. Mobayyen D. R. O. Morrison S. O'Neale M. A. Parker J. Sacton R. A. Sansum N. Schmitz G. W. Van Apeldoorn K. Varvell A. Vayaki H. Wachsmuth W. Wittek BEBC WA Collaboration 《Zeitschrift fur Physik C Particles and Fields》1989,44(1):79-87
Backward proton and pion production is studied in ν and \(\bar v\) charged current interactions in neon. The results are compared with other experiments and theory. The complete backward proton data is compatible with protons produced by reinteractions in the nucleus. However in events with only one proton, muon variables appear correlated to those for the backward proton, as expected by the two-nucleon correlation model. 相似文献
2.
Summary Optically pure (+)-beta-eudesmol is a possible starting material for the synthesis of several termite defense compounds. A
two step procedure for the isolation of gram quantities of (+)-beta-eudesmol from commercially availableAmyris balsamifera oil (syn. West Indian sandalwood oil), containing 8% beta-eudesmol, was developed. Step one consisted of an efficient vacuum
distillation of the total oil. Step two was a medium pressure LC separation with an AgNO3 impregnated silica gel stationary phase. Several other separation procedures failed due to the presence of many closely related
sesquiterpene alcohols (75% of the oil). 相似文献
3.
A. E. Giannakopoulos K. P. Baxevanakis A. Gouldstone 《Archive of Applied Mechanics (Ingenieur Archiv)》2007,77(2-3):113-122
The present work gives a systematic and rigorous implementation of Volterra dislocations in ordinary two-dimensional finite
elements using the thermal analogue and the integral representation of dislocations through the stresses. The full fields
are given for edge dislocations in anisotropic crystals, and the Peach–Koehler forces are found for some important examples. 相似文献
4.
The thermodynamics of adsorption of gallic acid (GA, 3,4,5-trihydroxylbenzoic acid) on the hanging mercury drop electrode (HMDE) surface was studied by temperature-dependent stripping voltammetry (TD-SV), at physiological pH 7.4. The thermodynamic parameters, e.g., Gibbs free energy, ΔG(ADS), enthalpy, ΔΗ(ADS) and entropy, ΔS(ADS), of adsorption have been determined at physiological temperatures 2-40 °C. Chemisorption of the radical species ≡[GA(OH)(2)(O(-))]* is the energetically important reaction. The thermodynamic data show a complex mechanism of adsorption of GA on the electrode surface, which is strongly dependent on temperature. At low-temperatures T<12 °C, adsorption is controlled by enthalpy, while at T>22 °C, adsorption is entropy driven. In the temperature range 12 °C and 22 °C, a combined enthalpy-entropy stabilization occurs. A mechanism is proposed which analyses the implication of thermodynamics to the interfacial adsorption of polyphenols with cell membranes under physiological conditions. 相似文献
5.
W. Wittek M. Aderholz P. Allport N. Armenise J. P. Baton M. Berggren F. W. Bullock M. Calicchio E. F. Clayton T. Coghen A. M. Cooper-Sarkar O. Erriquez P. Fitch N. Giannakopoulos J. Guy E. Hoffmann P. O. Hulth G. T. Jones P. Kasper U. F. Katz J. Kern H. Klein P. Marage E. Matsinos D. R. O. Morrison M. Neveu M. A. Parker N. Schmitz E. Simopoulou K. Varvell A. Vayaki W. Venus H. Wachsmuth BEBC WA Collaboration 《Zeitschrift fur Physik C Particles and Fields》1988,40(2):231-251
The average multiplicities of charged hadrons and of π+, π? and π0 mesons, produced in \(\bar v\) Ne and νNe charged current interactions in the forward and backward hemispheres of theW ±-nucleon center of mass system, are studied with data from BEBC. The dependence of the multiplicities on the hadronic mass (W) and on the laboratory rapidity (y Lab) and the energy fraction (z) of the pion is also investigated. Special care is taken to determine the π0 multiplicity accurately. The ratio of average π multiplicities \(\frac{{2\left\langle {n_{\pi ^O } } \right\rangle }}{{[\left\langle {n_{\pi ^ + } } \right\rangle + \left\langle {n_{\pi ^ - } } \right\rangle ]}}\) is consistent with 1. In the backward hemisphere \(\left\langle {n_{\pi ^O } } \right\rangle \) is positively correlated with the charged multiplicity. This correlation, as well as differences in multiplicities between \(\mathop v\limits^{( - )} \) and \(\mathop v\limits^{( - )} \) , \(\mathop v\limits^{( - )} \) scattering, is attributed to reinteractions inside the neon nucleus of the hadrons produced in the initial \(\mathop v\limits^{( - )} \) interaction. 相似文献
6.
7.
Knoop indentation tests have long been a standard method for material characterization due to the fact that they provide an easy, inexpensive non destructive and objective method of evaluating basic properties from small volumes of materials. In spite of the broad use, Knoop indentation has never been analysed and its methodology is basically empirical. The present work presents an extensive finite element study on the adhesionless contact of flat surfaces by Knoop indenter. The aim of this work is to explore the theoretical foundation for the commonly used Knoop test and shed light to the interesting details that make the Knoop test so useful and simple. Both elastic and elastoplastic responses are explored. The material of the contacting solid is modeled as homogeneous and isotropic. The effect of the Coulomb friction at the contact region is also considered. Subsequently, the computational results presented in the current study are compared with analytical and experimental results that exist in bibliography. 相似文献
8.
Ch. Sargentis K. Giannakopoulos A. Travlos D. Tsamakis 《Physica E: Low-dimensional Systems and Nanostructures》2007,38(1-2):85
Floating gate devices with nanoparticles embedded in dielectrics have recently attracted much attention due to the fact that these devices operate as non-volatile memories with high speed, high density and low power consumption. In this paper, memory devices containing gold (Au) nanoparticles have been fabricated using e-gun evaporation. The Au nanoparticles are deposited on a very thin SiO2 layer and are then fully covered by a HfO2 layer. The HfO2 is a high-k dielectric and gives good scalability to the fabricated devices. We studied the effect of the deposition parameters to the size and the shape of the Au nanoparticles using capacitance–voltage and conductance–voltage measurements, we demonstrated that the fabricated device can indeed operate as a low-voltage memory device. 相似文献
9.
K. Giannakopoulos N. Boukos A. Travlos T. Monteiro M.J. Soares M. Peres A. Neves M.C. Carmo 《Applied Physics A: Materials Science & Processing》2007,88(1):41-44
Isolated, self assembled ZnO nanoparticles are grown in two steps: by the electron beam evaporation of Zn on oxidised silicon
wafers, during which isolated Zn nanodots are grown, and a subsequent annealing in oxygen that results in the desired ZnO
nanodots. Low temperature PL measurements of the ZnO nanodots show that the near band edge part of the spectra is dominated
by a zero phonon line near 3.36 eV which is an overlap of two emitting lines near 3.363 eV and 3.367 eV. Characterization
by TEM and EELS shows that the nanoparticles are zinc oxide single crystals grown with their c-axis perpendicular to the substrate;
their distribution, size and crystallinity depend on the deposition parameters of zinc and the growth substrate. We discuss
the effect of these parameters on the morphology of the resulting material. Our approach demonstrates a simple method for
the growth of high purity isolated ZnO nanodots of similar sizes, distributed uniformly on a large surface.
PACS 61.46.Df; 81.05.Dz; 81.07.-b 相似文献
10.
N. Boukos C. Chandrinou K. Giannakopoulos G. Pistolis A. Travlos 《Applied Physics A: Materials Science & Processing》2007,88(1):35-39
ZnO nanorods were grown by a near-room-temperature, simple, chemical solution method on large-area Zn foils and substrate
materials such as silicon, and zinc oxide thin films on silicon and glass. Study of the ZnO nanorods on the different substrates
by electron microscopy methods shows that the morphology and size of the ZnO nanorods can be tuned varying the growth parameters
and the substrates used. The growth mechanism is briefly discussed. Photoluminescence experiments at room temperature reveal
a major emission peak of the nanorods at around 385 nm, which is attributed to the band edge transition of ZnO and weaker
defect-related visible band peaks.
PACS 81.05.Dz; 78.55.Et; 81.07.-b 相似文献