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51.
Several salts of α,ω-sulfates, MO3SO(CH2)n OSO3M(n=12, 14, 16, 18, and M=Li, Na, and K) were prepared from the corresponding α,ω-alkane diols. The Krafft points of these α,ω-sulfates with common counterion as estimated by electroconductivity measurements increased with the increase of the hydrocarbon chain length, and the effect of the counterions on the Krafft points of the α,ω-sulfates with the same hydrocarbon chain length was in the order : Li<Na<K. Solutions of the α,ω-sulfates, except disodium dodecanediol disulfate, showed two break points corresponding to the first and second critical micelle concentration in each plot of the electroconductivity as a function of the concentration. The existence of the second break point suggested that another aggregation of rearrangement of the existing aggregates occurs in α,ω-sulfate solutions in addition to the usual micelle formation. The first and second break points of α,ω-sulfates with sodium counterion decreased logarithmically with increasing total number of methylene groups. The relationships were given as follows: log(first break point)=−0.138Nc−0.095; log(second break point)=−0.104Nc−0.251. The effect of the counterions upon the break points of α,ω-sulfates with the same hydrocarbon chain length was in accordance with their positions in the lyotropic series.  相似文献   
52.
The NMR spectra of olefinic protons in the four representative conjugated fatty acid methyl esters, methylcis-9,trans-11-octadecadienoate, methyltrans-9,trans-11-octadecadienoate, methyl α eleostearate, and methyl β eleostearate, were studied. The chemical shift of each olefinic proton in these compounds was determined by considering their intramolecular environment. Coupling constants were also obtained as the results of spectral analysis.  相似文献   
53.
Necessary conditions were studied for the optimum operation of agglomeration granulation. The mechanisms that would realize these conditions were investigated by several experiments.On the basis of the results obtained, a novel granulating system involving a surface wetness control mechanism has been developed.The present paper describes the mixing and dispersing characteristics of the coating vessel, the detection method for wetness control, the particular spraying units, and the operating conditions thereof, together with the characteristics of this newly developed powder coating granulation system.This system has been shown to provide an easy and reproducible granulating technique even when products below 1 mm in size are required.  相似文献   
54.
The purpose of this study was to investigate the physiological and subjective responses of the European, Japanese (JPN) and US firefighters' helmet, gloves and boots for international standardisation. Three experimental conditions were evaluated (clothing mass: 9.4, 8.2 and 10.1 kg for the three conditions, respectively) at the air temperature of 32°C and 60% relative humidity. The results showed that there was no significant difference among the three conditions in oxygen consumption, heart rate, total sweat rate, rectal temperature and mean skin temperature, whereas peripheral temperatures and subjective perceptions were lower in the JPN condition than in the other conditions (P < 0.05). These results indicate that a 0.5-kg reduction in helmet mass and a 1.1-kg reduction in boot mass during exercise resulted in a significant decrease in head and leg temperatures and subjective perceptions, while a 1.9-kg reduction in total clothing mass had insignificant influences on the metabolic burden and overall body temperature.  相似文献   
55.
We present a new architecture level unified reliability evaluation methodology for chip multiprocessors (CMPs). The proposed reliability estimation (REST) is based on a Monte Carlo algorithm. What distinguishes REST from the previous work is that both the computational and communication components are considered in a unified manner to compute the reliability of the CMP. We utilize REST tool to develop a new dynamic reliability management (DRM) scheme to address time-dependent dielectric breakdown and negative-bias temperature instability aging mechanisms in network-on-chip (NoC) based CMPs. Designed as a control loop, the proposed DRM scheme uses an effective neural network based reliability estimation module. The neural-network predictor is trained using the REST tool. We investigate how system’s lifetime changes when the NoC as the communication unit of the CMP is considered or not during the reliability evaluation process and find that differences can be as high as 60%. Full-system based simulations using a customized GEM5 simulator show that reliability can be improved by up to 52% using the proposed DRM scheme in a best-effort scenario with 2–9% performance penalty (using a user set target lifetime of 7 years) over the case when no DRM is employed.  相似文献   
56.
We have developed a two‐way multi‐view 2‐D/3‐D display combining a liquid crystal lens and horizontally and vertically x times‐density pixels (HVxDP) arrangement. The two‐way multi‐view display features the same display resolution in 2‐D and 3‐D modes and a quite small color moiré for landscape and portrait, respectively, when using the HVxDP arrangement. In this paper, we realized suitable 3‐D properties for achieving a good balance between 3‐D moiré and 3‐D crosstalk for landscape and portrait by a two‐way liquid crystal lens with two kinds of focal lengths for the edge part and the center part of the lens.  相似文献   
57.
Takeda M  Yamamoto H 《Applied optics》1994,33(34):7829-7837
An interferometric technique for automated profilometry of diffuse objects has been proposed. It is based on the Fourier-fringe analysis of spatiotemporal specklegrams produced by a wavelength-shift interferometer with a laser diode as a frequency-tunable light source. Unlike conventional moiré techniques the proposed technique permits the objects to have discontinuous height steps and/or surfaces spatially isolated from one another. Experimental results are presented that demonstrate the validity of the principle.  相似文献   
58.
We have considered the behavior of the conductivity or the dielectric function of the one-dimensional (1-D) quantum sine-Gordon system (g2 = 4) for two models of impurities. We have used a Fermi-Bose relation and a self consistent t-matrix approximation. As for the conductivity at zero temperature, it appears when the concentration of impurities becomes larger than the critical concentration of impurities. It shows the linear increase near the critical concentration. As for the dielectric constant, its behavior is model dependent. We have numerically calculated the frequency dependence of the conductivity at zero temperature. The real part shows the second order increase near the critical frequency. The imaginary part shows the linear decrease from the origin.  相似文献   
59.
Yamamoto K  Ishida H 《Applied optics》1995,34(21):4177-4185
The optical behavior of a thin film, that is, peak positions and intensities, is discussed for transmission under a thin-film approximation. The infrared transmission spectra of thin films, both standing films and those on dielectric substrates, are simulated for s and p polarization at various angles of incidence. For spectral simulation, the matrix method is used in conjunction with noise-free complex refractive indices based on the dispersion theory. The peak positions in the simulated spectra are compared with transverse optic and longitudinal optic frequencies based on the macroscopic theory. The simulated peak intensities for the standing films are compared with the prediction based on the thin-film approximation. Furthermore, it is found from the spectral simulation for thin films on dielectric substrates that the peak intensity for a thin film may depend on the thickness and refractive index of the substrate.  相似文献   
60.
We report experimental results on enhanced backscattering from a plane mirror that is viewed through polymer-film-dispersed nematic liquid crystals. The distribution of the averaged intensity of the light reflected from the mirror placed behind the polymer film is investigated with an image-processing system when a Gaussian beam wave is incident. The enhanced light peak is observed in an incident beam direction, the result of which is predicted by a theory based on the circular Gaussian statistic random-phase-screen model. We pay attention to the enhancement dependence on parameters such as the distance between the polymer film and the flat mirror. The observed result is similar to a previous study by Jakeman et al. in which a random diffusive glass plate was used as a random-phase screen [J. Phys. D 21, 32 (1988)].  相似文献   
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