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121.
The omni-directional reflection (ODR) in a one-dimensional multilayered structure containing exponentially graded material is studied theoretically using the transfer matrix method. We propose a periodic multiplayer structure containing alternate layers of the exponentially graded refractive index and layers of constant refractive index. The reflectance for TE- and TM-modes of the structure are studied for different angles of incidence. We obtained two ODR bands, one in the visible and the other in the infrared region for both polarizations. The behavior of the ODR band in the infrared region is different from the usual Bragg ODR band in the visible region. The width of the ODR band for the TM-mode is larger that for the TE-mode in the wavelength range 850 nm–1050 nm. Such a structure with a large ODR band may be useful in the design of a broad infrared reflector. 相似文献
122.
The use of small-volume injections of hypertonic saline solutions (HSS) in resuscitation from hemorrhagic shock is accompanied by well-maintained and pronounced increases in coronary blood flow (CBF) and by increases in myocardial contractility. The present study was performed in open-chest, anesthetized dogs to evaluate the contribution of direct coronary vasodilator and positive inotropic effects of HSS to these therapeutic responses. The left anterior descending coronary artery (LAD) was cannulated and perfused at constant pressure (100 mm Hg) with normal arterial blood. CBF in LAD was measured electromagnetically, and used to calculate myocardial oxygen consumption (MVO2) and coronary arterial plasma osmolality. Percent segmental shortening in LAD bed (% SS) was evaluated with ultrasonic crystals. Measurements were obtained during infusion into LAD of 2.5, 5.0, and 7.5% HSS at 2 ml/min. These HSS solutions yielded calculated plasma osmolalities of 329 +/- 3, 361 +/- 8, and 378 +/- 10 mOsm/kg, respectively. The increases in plasma osmolality by 2.5% HSS were in the therapeutic range, whereas those by 5.0 and 7.5% HSS were supertherapeutic. HSS caused initial peak increases in CBF (reflecting decreases in coronary vascular resistance), which waned rapidly to achieve modest steady-state increases within 2-3 min. The magnitude of the peak and steady-state increases in CBF by HSS correlated to osmolality. The 2.5% HSS had no effect on MVO2 and % SS, whereas the 5.0% and 7.5% HSS increased these variables in an osmolality-dependent manner. Conclusions: (1) intracoronary infusions of HSS caused modest steady-state coronary vasodilation, (2) Supertherapeutic elevations of plasma osmolality by HSS were required for direct positive inotropic effects, and (3) the present findings suggest that the direct cardiac actions of HSS contribute minimally to the increases in coronary blood flow and myocardial contractility that follow the use of these solutions for resuscitation from hemorrhagic shock. 相似文献
123.
124.
Das M Sawamura T Abe M Kaneko JH Homma A Fujita F Tsuda S Nishitani T 《Radiation protection dosimetry》2004,110(1-4):325-331
Superheated emulsions being inexpensive, easy to fabricate, and having tissue equivalent composition make them as one of the popular neutron dosemeters. One more advantage is that they can be made insensitive to gamma rays by the choice of the sensitive liquid. It is observed that the response of commercially available bubble detector to neutron decreases above 20 MeV while its response is roughly flat in the 0.1-15 MeV region. This restricts its application as a dosemeter to high-energy neutrons. The response of bubble detector from Bubble Technology Industries, has been observed by using Pb-breeder for high-energy neutrons from different facilities in Japan. It is observed that 2-3 cm Pb-breeder is effective in increasing the response of the detector to the nominal value. Theoretical calculation using MCNPX code indicates an increase in neutrons in the energy range of 0.1-10 MeV with Pb-breeder. The present work indicates the possibility of using the bubble detector as a dosemeter to high-energy neutron using a Pb-breeder of proper thickness. 相似文献
125.
In this paper, we introduce a new impossible differential cryptanalysis of Zodiac that is considerably more effective than the one in the previous work (Hong et al., 2002). Using two new 13-round impossible differential characteristics and the early abort technique, this 3R-Attack breaks 128-bit key full-round Zodiac with complexity less than 271.3 encryptions, which is practical. This result is approximately 248 times better than what mentioned in the earlier work. Our result reveals depth of Zodiac’s weakness against impossible differential cryptanalysis due to its poor diffusion layer. We also obtain a tighter upper bound for time complexity. 相似文献
126.
Joakim Riikonen Jimi Rantanen Rinez Thapa Nguyen T. Le Séverinne Rigolet Philippe Fioux Petri Turhanen Nelli K. Bodiford Jhansi R. Kalluri Timo Ikonen Tuomo Nissinen Bénédicte Lebeau Jouko Vepsäläinen Jeffery L. Coffer Vesa-Pekka Lehto 《Journal of the American Ceramic Society》2021,104(2):766-775
Nanostructured silicon carbide (SiC) is an exceptional material with numerous applications, for example, in catalysis, biomedicine, high-performance composites, and sensing. In this study, a fast and scalable method of producing nanostructured SiC from plant materials by magnesiothermic reduction via self-propagating high-temperature synthesis (SHS) route was developed. The produced biogenic material possessed a high surface area above 200 m2/g with a SiC crystallite size below 10 nm, which has not been done previously by SHS. This method enables affordable synthesis of the material plant-based precursors in a reaction that only takes a few seconds, thereby paving a way for nanostructured SiC production in high volumes using renewable resources. The material was also functionalized with carboxylic acid and bisphosphonate moieties, and its use as metal adsorbent in applications such as wastewater remediation was demonstrated. 相似文献
127.
A. Shankar D. P. Rai Sandeep R. Khenata R. K. Thapa P. K. Mandal 《International Journal of Thermophysics》2016,37(11):108
Density functional theory-based calculations of the elastic and electronic properties with magnetic moments of the filled skutterudite \(\mathrm{EuRu}_{4}\mathrm{As}_{12}\) have been performed in its ferromagnetic ground state. The full-potential linearized augmented plane wave (FP-LAPW) method has been used for the study presented here. The numerical values of the elastic parameters are estimated within the framework of the Voigt–Reuss–Hill approximations. The energy band structure calculation performed near the Fermi energy level shows the metallic nature of the material with a high value of Seebeck coefficient (S). The presence of an exchange splitting of Eu-4f states suggests their appreciable contribution toward the magnetic behavior. The analysis of the thermal transport properties confirms the result obtained from the electronic structure calculation with Seebeck coefficient of \(118\,\,\upmu \hbox {V/K}\) and the figure of merit (ZT) value of 0.51, at room temperature. The estimated values of S and ZT indicate the possibility of the thermoelectric applications of the sample material. 相似文献
128.
The effect of two-photon absorption (TPA) on all-optical logic operation in quantum-dot semiconductor optical amplifier (QD-SOA) has been carried out. We model the rate equation with the TPA effect for the logic XOR gate, AND gate, and, for pseudo-random bit sequence (PRBS) generation. The simulated results indicate that the TPA induced pumping increases the output Q-factor (quality). The results show that the quality of the output depends on the input pulse width and the speed of operation. The PRBS system can operate at 250 and 320 Gb/s but an increase in pulse width decreases the output Q-factor. 相似文献
129.
Vinod VP Phadtare S Joshi HM Sastry M Rao M 《Journal of nanoscience and nanotechnology》2007,7(8):2767-2773
This study describes the synthesis of a free-standing nanogold membrane by the spontaneous reduction of aqueous chloroaurate ions by the diamine molecule DAEE at a liquid-liquid interface. The free standing nanogold membrane, provides a biocompatible surface for the immobilization of proteins. F-Protease (F-Prot) was then bound to the nanogold membrane via interaction with the gold nanoparticles leading to a new class of biocatalyst. A highlight of the new biocatalyst wherein the enzyme is bound to the nanogold membrane is the ease with which separation from the reaction medium may be achieved by simple filtration. In relation to the free enzyme in solution, the F-Prot in the bioconjugate material exhibited a slightly higher biocatalytic activity and significantly enhanced pH and temperature stability. The F-Prot nanogold membrane bioconjugate material also exhibited excellent biocatalytic activity over ten successive reuse cycles. 相似文献
130.
This paper examined the effects of a parenting intervention targeting working parents called Workplace Triple P. The intervention targeted both parenting and work factors, focusing on key transition times (e.g., from home to work) and trained parents to more effectively manage these transitions. One-hundred-and-twenty-one working parents with children ranging in age from 1–16 years were randomly assigned to either a Workplace Triple P condition (WPTP) or to a waitlist control condition (WLC). Results showed that parents who had received the intervention reported significantly lower levels on measures of personal distress and dysfunctional parenting; and higher levels of work commitment, work satisfaction, and self-efficacy. Implications for the delivery of parenting interventions as employee assistance programs are discussed along with how such interventions can enhance work and family life. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献