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941.
This paper introduces a powerful design and analysis tool named SIMCAT, that is developed to support applications to license a CANDU nuclear reactor, refurbish projects, and support the existing CANDU stations. It consists of the CATHENA (Canadian Algorithm for Thermo-Hydraulic Network Analysis), the control logics from C6SIM (CANDU 6 Analytical Simulator), and a communication protocol, PVM (parallel virtual machine). This is the first time that CATHENA has been successfully coupled directly with a program written in another language. The independence of CATHENA and the C6SIM controllers allows the development of both CATHENA and C6SIM controller to proceed independently.  相似文献   
942.
The present study investigates the effect of air flowrate on the adsorption systems both numerically and experimentally. Tests are performed with Zeolite 4A adsorbent. The size of test desiccant channel section is 10 cm × 10 cm × 10 cm, and three test sections in series connections are used as the test section during adsorption and desorption. During adsorption, the inlet pressure is kept at 9 bar while it is reduced to 1.16 bar during desorption. The simulation is first validated with the experimental data. The simulation indicates though a higher airflow during adsorption can produce dry air quickly but may not be able to attain a prescribed very low dew point temperature. Yet lower airflow can dehumidify more moisture and attain much lower dew point but requires substantial time. For the required energy to generate the same dry air flow volume in cyclic operation, it was obvious that a lower flowrate like 150 standard liter per minutes (SLPM) is about 4% lower than that of a higher flowrate of 400 SLPM. For effective regeneration during desorption, a non-uniform heating provided at the first section is proved to be much effective than the uniform heating. It is found that the desiccant loading for only heating at the first section outperforms other arrangements, giving 10% lower desiccant loading than the uniform heating.  相似文献   
943.
ABSTRACT:  Differential scanning calorimetry (DSC) and dynamic oscillatory shear testing were performed to study the influence of inulin (Raftiline® HP-gel and Raftiline® ST-gel) and oligofructose (Raftilose® P95) on the thermal stability and gelation (using glucono-δ-lactone [GDL] as a coagulant) of soy protein isolate (SPI) dispersions. Addition of 10% (w/v) inulin/oligofructose or sucrose increased ( P < 0.05) the peak denaturation temperatures ( Tm ) of 7S and 11S soy proteins in SPI dispersion (5%[w/v], pH 7.0) by an average of 1.9 and 2.3 °C, respectively. GDL induced SPI thermal gelation, and the gel rheology was affected by both the pH decline and the specific temperature of heating. Addition of inulin/oligofructose (8%, w/v) improved the gelling properties of preheated SPI dispersion (8%, w/v) coagulated with GDL, showing 14.4 to 45.6% increase ( P < 0.05) in gel rigidity ( G ' value) at the end of heating (81 °C). Microstructural examination revealed a denser protein cross-linking structure and reduced pore sizes in SPI gels containing inulin/oligofructose. In general, inulin was more capable of improving SPI gelation than oligofructose, suggesting that the degree of fructose polymerization in the fructans was of thermal and rheological importance.  相似文献   
944.
A planar antenna array reflector with retrodirectivity in both the E-plane and the H-plane is analyzed and demonstrated at X band. The reflector consists of six pairs of slot-coupled patch antennas arranged using the Van Atta approach. The total reflected field from the reflector is separated into three primary components; that is, the reradiation field from the patch antennas (RFPA), the scattering field from the patch antennas (SPPA), and the scattering field from the ground plane (SFGP). The first two components are calculated by using the method of moments together with a mixed potential integral equation and the last one is by the physical optics (PO) method combined with the method of equivalent currents (MEC). By tuning the microstrip-line lengths, the total reflected field contributed by the three components is designed to possess a broad-beamed pattern in both the E-plane and the H-plane. The measured patterns show good agreement with the designed ones  相似文献   
945.
Previous studies suggest that the relationship between genes and nonsyndromic cleft lip +/- cleft palate (CLP) or cleft palate only (CP) may be modified by the environment. Using data from a population-based case-control study, we examined allelic variants for three genes, i.e., transforming growth factor alpha (TGFA), transforming growth factor beta 3 (TGFB3), and Msh (Drosophila) homeobox homolog 1 (MSX1), and their interactions with two exposures during pregnancy (maternal cigarette smoking and alcohol consumption) as risk factors for CLP and CP. For each cleft phenotype, risk estimates associated with most allelic variants tended to be near unity. Risk estimates for maternal smoking (> or = 10 cigarettes/day) were significantly elevated for CP and were most elevated among infants with allelic variants at the TGFB3 or MSX1 sites. By comparison, risk estimates for maternal alcohol consumption (> or = 4 drinks/month) were significantly elevated for CLP and were most elevated among infants with allelic variants at the MSX1 site. Our results suggest that development of CLP and CP may be influenced independently by maternal exposures but more significantly by interaction of such exposures and specific allelic variants.  相似文献   
946.
The space vector pulse‐width‐modulation technique is extensively applied in the three‐phase power electronics circuits because of its easy digital implementation and wide linear modulation range features. However, the attempt of this technique for the single‐phase Z‐source inverter has seldom been reported because of its unique topology and operational characteristics. In this paper, based on an in‐depth mathematical derivation and theoretical explanation, the space vector pulse‐width‐modulation principles have been discussed in detail. Various implementation schemes are demonstrated, and a comparison study for selected switching patterns is conducted. In addition, the theoretical analysis is validated by both the simulation and experimental results. This work will be helpful for understanding the space vector pulse‐width‐modulation concept and modulation techniques of the single‐phase full‐bridge Z‐source inverters. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
947.
948.
The purpose of this study was to directly use the writing techniques for the complex electrode edge isolation of transparent conductive polymer (TCP) thin films by a nanosecond pulsed UV laser processing system. The processing parameters including the laser pulse energy, the pulse repetition frequency, and the scan speed of galvanometers were examined to ablate the TCP films deposited on polyethylene terephtalate substrates of 188 microm thick. The thickness of TCP films was approximately 20 nm. The laser pulse repetition frequency and the scan speed of galvanometers were applied to calculate the overlapping rate of laser spots and to discuss the patterning region quality. Surface morphology, edge quality, and width and depth of edge isolated patterning structures after laser ablation process were measured by a three-dimensional confocal laser scanning microscope. In addition, the electrical conductivity of ablated TCP films was measured by a four-point probes instrument. After isolated line patterning was formed, the ablated TCP films with a better edge quality were obtained directly when the overlapping rate of laser spots, the scan speed, and the pulse repetition rate were 83.3%, 200 mm/s, and 40 kHz, respectively. The better surface morphology of electrode pattern structures was also obtained when the scan speed and the pulse repetition rate were 500 mm/s and 40 kHz, respectively.  相似文献   
949.
The effect of twisting on the electrical resistance of a raw single-walled carbon nanotube (SWCNT) rope was investigated and found to increase with increasing number of twists, varying from 28.7 Ω initially to 35.2 Ω after 12 twists. There are two reasons for this. One is that the twisting generated more contact points between the SWCNTs and catalytic nanoparticles, resulting in a high density of high local resistance points. The other is that the protrusion of SWCNTs in a rope twisted a large number of times (12–15 twists) partially interrupted the conducting path. By using a 9-V battery, ignition of the rope could be produced at a threshold resistance between 17.5 and 21.1 Ω, and this could be used to ignite ferrocene with the process lasting for several minutes.  相似文献   
950.
The Zernike electrostatic phase plate (ZEPP) consisting of three ring electrodes and two insulating rings has been fabricated using Micro Electro-Mechanical System processes. The electrostatic field produced in the phase plate was measured by electrostatic force microscopy. The electrostatic field and focal length of the phase plate is calculated using electron optics principles. The comparison of the experimental electrostatic field and the theoretical calculated is discussed. Finally, we report the application of ZEPP to enhance contrast of the SiON(x)/SiO(2) interface in an NMOS semiconductor device. The quantitative analysis of the contrast enhancement versus the applied bias is discussed in detail.  相似文献   
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