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821.
822.
In the present work, bimetallic silver/zinc was applied into the degradation of trihalomethanes, THMs: CHCl3, CHBrCl2, CHBr2Cl, and CHBr3. The kinetics reaction rates and removal efficiencies of the THM compound mixtures, in the aqueous solutions, were investigated. Batch experiments were conducted under mild conditions, ambient temperature, and pressure. The primary degradation reaction followed a pseudo-first-order kinetic law. The first-order rate constants and the degradation efficiencies followed the decreasing order of CHBr3>CHBr2Cl>CHBrCl2>CHCl3. The bond dissociation energy and hydrophilic/hydrophobic characteristics of the THM compounds may become the most important parameters affecting the degradation kinetics and efficiency by bimetallic Ag/Zn.  相似文献   
823.
A conjugate numerical model has been proposed to investigate the problem of cooling a fluid flowing through a spiral coil immersed in a chilled water container, which is common in many beverage dispensers. A simple axisymmetric numerical procedure is described to determine the temperature of the fluid in the spiral coil and that of the coil surface. A one-dimensional heat balance equation for the fluid within the coil is utilized to update the fluid and wall surface temperatures, which are needed to calculate the temperature field in the water container with solid ice walls. The SIMPLE algorithm has been adopted along with the standard k-epsilon turbulence model equations. A reasonably good agreement between the numerical predictions and experimental results has been achieved.  相似文献   
824.
Abstract— A thick‐film ceramic‐sheet PDP provides a long sustain discharge gap of 0.45 mm, enabling the use of positive column discharges. The discharges are established in the middle of the discharge space and are completely free from touching the surface of substrates. This allows for the reduction in diffusion losses of the charged particles. To further improve the efficacy, delayed D pulses are applied to the address electrodes during the sustain period. Although the pulses only draw a little current, they perturb the electric field, reducing the peak discharge current and hence resulting in higher efficacy and luminance. The efficacy and luminance increase by 35% and 38%, respectively, with the delayed D pulses. These pulses are incorporated into the contiguous‐subfield erase‐addressing drive scheme for TV application. A short gap of 70 μm between the sustain and data electrodes generates a fast‐rising discharge and allows a high‐speed addressing of 0.25 μsec. This provides 18 contiguous subfields for the full‐HD single‐scan mode, with 70% light emission duty. A luminous efficacy of 6.0 lm/W can been attained using Ne + 30% Xe 47 kPa, a sustain voltage of 320 V, and a sustain frequency of 3.3 kHz, when the luminance is 157 cd/m2. Alternatively, the panel can achieve 4.2 lm/W and 1260 cd/m2 by increasing the sustain frequency to 33 kHz.  相似文献   
825.
The ion-nitriding behaviour of four iron alloys containing between 0.11 and 1.48 wt% titanium was investigated in the-phase region to discuss kinetics of the growth of the nitriding layer. The ion-nitriding experiments have been made at 823 K. Two nitriding layers were observed: a thin surface layer which mainly consists of Fe4N; an internal nitriding layer beneath the surface layer, where the nitride formed was found to be TiN. The growth of the internal nitriding layer is controlled by a diffusion process of nitrogen in the matrix metal. The apparent diffusion coefficient of nitrogen in the nitriding layer, evaluated using the rate equation proposed for internal oxidation, increases linearly with the volume fraction of titanium nitride. Furthermore, by excluding the effect of the titanium nitride from the apparent diffusion coefficient, the diffusion coefficient of nitrogen in-iron was calculated, being in good agreement with that reported so far. In addition, the increase in hardness in the internal nitriding layer has been discussed.  相似文献   
826.
Mouse monoclonal anti–human IL–2 receptor antibody(BB10) inhibits EL–2–dependent human T–cellproliferation. It has been used in clinical trials in the transplantationfield and promising results are being accumulated. Mouse B–B10antibody was humanized by grafting all CDRs and some frameworkamino add residues onto human antibodies, KAS for VH and PAYfor Vx. Nine humanized B–BlOs with differently graftedframework residues were constructed and assessed for their biologicalactivities. One of these humanized B–B10, M5, showed nearlythe same activity as the mouse B–B10. The 49th residueof Vx was demonstrated to play a crucial role in the antigen–antibodyinteraction by 3–D structure analysis with a computermodeling system.  相似文献   
827.
Horino  Hideyuki  Liu  Suwen  Sano  Manami  Wako  Sugio  Hiratsuka  Atsuko  Ohno  Yuichi  Kobal  Ivan  Matsushima  Tatsuo 《Topics in Catalysis》2002,18(1-2):21-26
Two-directional N2 desorption was found in N2O decomposition on Pd(110) at 100–160 K. It collimated ±43° off the surface normal in the (001) plane. A hot-atom-assisted model is proposed for N2 desorption. Inclined O2 desorption was simulated by hot atoms emitted from aligned oxygen molecules on stepped Pt(112) at 308 nm irradiation.  相似文献   
828.
The relationship between the fluorescence behavior and crystallinity of poly(1,4-butylene terephthalate) (PBT) films, prepared by a spin-casting method, was investigated. Throughout the fluorescence measurements of PBT thin films having different crystallinities, the main-chain phenylene fluorescence near 320 nm and that near 365 nm were assigned to monomer fluorescence mainly from crystalline regions and excimer fluorescence from amorphous regions, respectively. It was found that the ratio of the fluorescence intensity at 320 nm to that at 365 nm can be an effective indicator of PBT crystallinity. The present work should provide a quick and nondestructive method for determining the crystallinity of PBT factory products.  相似文献   
829.
830.
Data abstraction and inheritance, some of the most important features in constructing a large, clean software system, in a logic programming language Prolog/KR, an expansion of Prolog, are described. First two kinds of processes are added; one is called NPO, which is mainly used to implement a generator, the other is called CPO, which is mainly used to implement an abstract data object. Then synchronization features are added to implement abstract data types that can be used concurrently. Using this feature it is possible to employ pipes for communications among processes. Finally, inheritance mechanism is added to define hierarchies among objects.  相似文献   
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