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11.
Cristiano Rony Ponce Enrique Pagano Daniel J. Granzotto Mathieu 《Nonlinear dynamics》2019,96(2):1243-1266
Nonlinear Dynamics - The electronic circuit of a DC–DC boost power converter under a specific sliding mode control strategy is analyzed. This circuit is modeled as a discontinuous piecewise... 相似文献
12.
Rony Snyders Christophe Roberges Marie-Pierre Faure Jolanta E. Klemberg-Sapieha 《Surface science》2007,601(1):112-122
We studied the mechanism of adhesion between N2 plasma treated polypropylene (PP/N2) backing and a hybrid hydrogel (HG) produced by chemical crosslinking between poly(ethylene glycol) and soy albumin. The work of adhesion, measured by peel testing, was found to be 25 times higher for PP/N2 compared to untreated PP (≈5.0 J/m2 versus ≈0.2 J/m2). In order to understand the adhesion mechanism, we performed a detailed analysis of the surface chemical composition of PP and PP/N2 using X-ray photoelectron spectroscopy (XPS), chemical derivatization and attenuated total reflectance infra-red (ATR-IR) measurements. The results confirm incorporation of different nitrogen- (amine, amide,…) and oxygen- (hydroxyl, carboxyl,…) containing chemical groups on the PP/N2 surface. The derivatized functions were primary amine, hydroxyl, carboxyl and carbonyl groups. Chemical derivatization reactions validated the XPS results (except for carbonyl groups), and they clearly underlined the essential role of primary amine groups in the adhesion process. In fact, after derivatization of the amine functions, the work of adhesion was found to be 0.41 ± 0.12 J/m2. Participation of amine groups in the formation of covalent bonds at the interface between PP/N2 and HG was directly confirmed by ATR-IR measurements. 相似文献
13.
Hollow fiber enzyme reactors 总被引:1,自引:0,他引:1
P R Rony 《Journal of the American Chemical Society》1972,94(23):8247-8248
14.
Thomas Fenzl Chadi Touma Christoph PN Romanowski Jörg Ruschel Florian Holsboer Rainer Landgraf Mayumi Kimura Alexander Yassouridis 《BMC neuroscience》2011,12(1):29
Background
Neuronal mechanisms underlying affective disorders such as major depression (MD) are still poorly understood. By selectively breeding mice for high (HR), intermediate (IR), or low (LR) reactivity of the hypothalamic-pituitary-adrenocortical (HPA) axis, we recently established a new genetic animal model of extremes in stress reactivity (SR). Studies characterizing this SR mouse model on the behavioral, endocrine, and neurobiological levels revealed several similarities with key endophenotypes observed in MD patients. HR mice were shown to have changes in rhythmicity and sleep measures such as rapid eye movement sleep (REMS) and non-REM sleep (NREMS) as well as in slow wave activity, indicative of reduced sleep efficacy and increased REMS. In the present study we were interested in how far a detailed spectral analysis of several electroencephalogram (EEG) parameters, including relevant frequency bands, could reveal further alterations of sleep architecture in this animal model. Eight adult males of each of the three breeding lines were equipped with epidural EEG and intramuscular electromyogram (EMG) electrodes. After recovery, EEG and EMG recordings were performed for two days. 相似文献15.
Masahiro Ueda Kazuhiko Ishikawa Chen Jie Sanae MizunoYasunori Touma 《Optics and Lasers in Engineering》1994,21(5):307-316
A highly sensitive method for the detection of blood leakage has been developed, and a practical sensor system for blood concentration measurement has been constructed. The present method is based on the attenuation of laser light by blood cells. The effects of the fluctuations of the incident laser light power are eliminated by normalizing the attenuated light intensity by the incident light intensity. A part of the incident laser light is reflected by a beam splitter mounted at the entrance of the test cell, of which the power is measured to provide base data for normalization. The optical path is extended to enhance sensitivity by using a pair of side mirrors. This multi-reflection method is very effective to increase sensitivity; the maximum sensitivity obtained for blood concentration is about 4 X 10-6 by volume, which is significantly higher than that of the conventional sensors. 相似文献
16.
Six different embryogenic cell lines of Pinus nigra Arn. have been cryopreserved in liquid nitrogen using cryoprotection with sucrose (18%) and DMSO (7.5%). Post-thaw growth and tissue proliferation have been observed in five cell lines. The survival levels after storage in liquid nitrogen reached values between 62.5 and 100%. Growth of recovered embryogenic cells as well as somatic embryos is similar to the non-frozen tissues maintained in long-term culture. Somatic embryo maturation and plantlet regeneration occurred in all selected cell lines. 相似文献
17.
Rony A. Bitan 《Journal of Number Theory》2011,131(9):1657-1671
For a torus T defined over a global field K, we revisit an analytic class number formula obtained by Shyr in the 1970s as a generalization of Dirichlet?s class number formula. We prove a local-global presentation of the quasi-discriminant of T, which enters into this formula, in terms of cocharacters of T. This presentation can serve as a more natural definition of this invariant. 相似文献
18.
This article describes the finite-field (FF) approach for calculating static (hyper)polarizabilities based on the divide-and-conquer (DC) method. The method is assessed by the Hartree?CFock (HF) and post-HF calculations of ??-conjugated model systems: a terminal donor or acceptor substituent on polyene chains. The DC?CFF approach enables the evaluation of molecular polarizabilities with highly accurate coupled-cluster theory. Numerical assessments demonstrate that the (hyper)polarizabilities calculated by the present DC?CFF method agree with the conventional FF results to within a few percent by employing an appropriate buffer size. 相似文献
19.
This paper presents high-resolution computations of a two-phase gas-solid mixture
using a well-defined mathematical model. The HLL Riemann solver is applied to
solve the Riemann problem for the model equations. This solution is then employed
in the construction of upwind Godunov methods to solve the general
initial-boundary value problem for the two-phase gas-solid mixture. Several
representative test cases have been carried out and numerical solutions are
provided in comparison with existing numerical results. To demonstrate the
robustness, effectiveness and capability of these methods, the model results
are compared with reference solutions. In addition to that, these results are
compared with the results of other simulations carried out for the same set of
test cases using other numerical methods available in the literature. The diverse
comparisons demonstrate that both the model equations and the numerical methods
are clear in mathematical and physical concepts for two-phase fluid flow problems. 相似文献
20.