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71.
M. Ivković M.A. Gonzalez S. Jovićević M.A. Gigosos N. Konjević 《Spectrochimica Acta Part B: Atomic Spectroscopy》2010
The results of an experimental study of the He I 447.1 nm line and its forbidden component at high electron number density are presented and compared with profiles calculated using computer simulation method. Michelson interferometer at 632.8 nm was used to measure plasma electron number density in the range (1–7) × 1023 m− 3 while electron temperatures for the same experimental conditions in the range of 25 000 K to 35 000 K were determined using several spectroscopic techniques. The agreement of experimental overall line shape with computer simulation results is within 10% of what is well within theoretical and experimental uncertainty. This favorable comparison enabled the development of a simple approximate formula for the evaluation of electron number density from the measurement of wavelength separation between peaks of allowed and forbidden lines. This technique of plasma diagnostics is not sensitive to the presence of self-absorption of strong He I allowed line. The derivation of approximate formula with estimated accuracy of 15% was followed by detailed comparison with other experimental and theoretical data. 相似文献
72.
In this paper, we use random walk theory to describe the length dynamics of microtubules, one of the principal components of the cytoskeleton. We present a simple two-state model (growing and shrinking) of microtubule length evolution that incorporates a variable rate of switching between the states. Using the generating function technique, we calculate the mean length of microtubule, its variance and diffusion coefficient. We also report analytical and computer simulation results for the mean number of positive monomers in microtubule, and find good qualitative agreement with experimental data. 相似文献
73.
V. N. Prudnikov A. P. Kazakov I. S. Titov Ya. N. Kovarskii N. S. Perov A. B. Granovsky I. Dubenko A. K. Pathak N. Ali J. Gonzalez 《Physics of the Solid State》2011,53(3):490-493
The quasi-diamagnetism effect that manifests itself in the negative magnetic susceptibility observed in weak magnetic fields
during cooling of samples below some critical temperature has been revealed in Ni48Co2Mn35In15 Heusler alloys. The effect has been attributed to a strong nonequilibrium of the system due to the presence of magnetic and
structural disorders and exchange anisotropy. 相似文献
74.
R. PereiraS. Skowronek A.González Ureña A. PardoJ.M.L. Poyato A.H. Pardo 《Journal of Molecular Spectroscopy》2002,212(1):17-21
Rotationally resolved spectra of the CaH radical using a supersonic molecular beam are reported. Thus, high energy resolution of the (1+1′) REMPI spectra corresponding to the A←X and B←X electronic transitions were measured which allowed for the first time a clear and precise analysis of the low rotational part (J≤7) of the CaH spectrum. A comparison with previous studies revealed that the commonly accepted energy separation between the two band heads of B−X (v′=1, v′=0) of 10 cm−1 is not correct. A value of ca. 1.6 cm−1 was found to be more realistic. On the other hand, the present study confirmed that the perturbation appears only for v′=1, N′>3 of the B state. 相似文献
75.
Ultrasound has been used to non-destructively assess the quality of many foods such as meat, fish, vegetables and dairy products. This paper addresses the applications of low intensity ultrasonics in the cheese manufacturing processes and highlights the areas where ultrasonics could be successfully implemented in the future. The decrease of ultrasonic attenuation during the renneting process can be used to determine the optimum cut time for cheese making. The ultrasonic velocity increases during maturation for those types of cheese that become harder during this manufacturing stage, thus being an indicator of the maturity degree. Moreover, ultrasonic measurements could be linked to sensory parameters. From the ultrasonic velocity measurements at two different temperatures, it is possible to assess cheese composition, thus allowing an improvement in the quality and uniformity of cheese commercialization. In addition, in pulse-echo mode it is possible to detect cracked pieces due to abnormal fermentations and also to assess the distance of the crack from the surface. 相似文献
76.
André JM Pardo B Bonnelle C 《Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics》1999,60(1):968-978
General formulation of the xuv intensity emitted when relativistic electrons cross through any periodic stratified medium is presented in the framework of electromagnetism in continuous media. Application is made to the resonant transition radiation emitted in the geometries of both normal and oblique incidence. In the first case, agreement is found between our calculated results and published values. Intensity emitted by a periodic multilayer stack used in the Bragg conditions is determined and the practical interest of a such a radiation source is discussed. 相似文献
77.
La Iglesia A. García V. Gonzalez Pozas J. M. Martín 《Journal of Thermal Analysis and Calorimetry》1975,8(2):273-278
Journal of Thermal Analysis and Calorimetry - Les anomalies que nous avons observées, dans le cas de l'oxydation de fils de nickel, peuvent s'interpréter en faisant appel à... 相似文献
78.
Ohne Zusammenfassung 相似文献
79.
Maryam?FaizEmail author Laia?Acarin Bernardo?Castellano Berta?Gonzalez 《BMC neuroscience》2005,6(1):26
Background
The forebrain subventricular zone (SVZ)-olfactory bulb pathway and hippocampal subgranular zone (SGZ) generate neurons into adulthood in the mammalian brain. Neurogenesis increases after injury to the adult brain, but few studies examine the effect of injury on neural and glial precursors in the postnatal brain. To characterize the spatio-temporal dynamics of cell proliferation in the germinative zones, this study utilized a model of postnatal damage induced by NMDA injection in the right sensorimotor cortex at postnatal day 9. 相似文献80.
Electrically contacted gold-nanocluster arrays formed within electromigration-induced break junctions exhibit bright, field-dependent electroluminescence in the near infrared (650-800 nm). Intensity autocorrelation of spatially isolated individual nanocluster emission driven at high electrical frequency (f(ac)= approximately 200 MHz) reveals antibunched electroluminescence at room temperature. These results demonstrate the single quantum nature of several-atom gold molecules and suggest their use as room-temperature electrically driven single-photon sources. 相似文献