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81.
International Journal on Software Tools for Technology Transfer - We show how to underapproximate the procedure summaries of recursive programs over the integers using off-the-shelf analyzers for...  相似文献   
82.
We report the distorted wave Born approximation results of triple differential cross section of Ar (3p) by positron and electron impact. We compare the results of our calculations with the recent available experimental and theoretical results. We also provide a comparison of our positron impact ionization results with the electron impact ionization results to understand the effect of projectile charge on the projectile-target interaction.  相似文献   
83.
在过去的15年内,印度印刷业发生了天翻地覆的变化。1990年,印度发起了一场破除贸易壁垒,实现经济自由化的改革。为了使印度经济与全球经济更好地融合,印度加快了推进私人化的进程。在这场改革中,许多印度印刷企业开始引进最新的技术和设备,这也为印度印刷业打开了通向现代化的大门。在过去的15年中,印度的年平均综合增长速度超过了12%,而包装行业目前更是达到超过16%的增长速度。  相似文献   
84.
Alumina-coated multi-wall carbon nanotubes were synthesized and characterized by scanning electron microscopy, X-ray diffraction, and FTIR. They were used as an adsorbent for the removal of lead ions from aqueous solutions in two modes, batch and fixed bed. In the batch mode, experiments were carried out to investigate the effect of contact time, agitation speed, adsorbent dosage and solution pH on the removal of lead. The coated nanotubes exhibit better removal ability over uncoated. For fixed-bed columns, thickness of the layer and flow rate were investigated. Increasing the thickness and decreasing the flow rate enhanced the removal of lead. The prepared adsorbent displayed the main advantage of separation convenience when a fixed-bed column was used compared to the batch adsorption treatment.  相似文献   
85.
86.
The aim of this article is to present the ultrasonic machining of an alumina-based engineering ceramic composite. The machining mechanism and the behavior of certain tool material and work material combinations with respect to penetration rate and tool-wear rate under the influence of different parameters in ultrasonic machining are discussed in this paper. The shocking movement and cutting mechanics of the abrasive particle under the tip of the vibrating tool have been observed using high-speed photographic equipment. The machined surface has been analyzed by using a scanning electron microscope. Surface roughness values were measured and plotted at entry and at exit of the holes for different types and sizes of holes using the surface roughness-measuring instrument "Perthometer."  相似文献   
87.
The use of invariants is an important tool for analysis of distributed and concurrent systems modeled by Petri nets. For a large practical system, the computation of desired invariants by the existing techniques is a time-consuming task. This paper proposes a theoretical foundation for simplified computation of desired invariants. We provide invariant-preserving Petri net reduction rules followed by the conditions for the existence of invariants in various well-structured nets. If an invariant exists, it can be found directly from the net structure using the formulas derived, or by applying the existing techniques on the reduced net.  相似文献   
88.
Bottom Ash, a power plan t waste material and De-Oiled Soya, an agriculture waste product were successfully utilized in removing trisodium 2-hydroxy-1-(4-sulphonato-1-naphthylazo)naphthalene-3,6-disulphonate--a water-soluble hazardous azo dye (Amaranth). The paper incorporates thermodynamic and kinetic studies for the adsorption of the dye on these two waste materials as adsorbents. Characterization of each adsorbent was carried out by I.R. and D.T.A. curves. Batch adsorption studies were made by measuring effects of pH, adsorbate concentration, sieve size, adsorbent dosage, contact time, temperature etc. Specific rate constants for the processes were calculated by kinetic measurements and a first order adsorption kinetics was observed in each case. Langmuir and Freundlich adsorption isotherms were applied to calculate thermodynamic parameters. The adsorption on Bottom Ash takes place via film diffusion process at lower concentrations and via particle diffusion process at higher concentrations, while in the case of De-Oiled Soya process only particle diffusion takes place in the entire concentration range.  相似文献   
89.
Parabolic solar collector collects the radiant energy emitted from the sun and focuses it at a point. Parabolic trough collectors are the low cost implementation of concentrated solar power technology that focuses incident sun light on to a tube filled with a heat transfer fluid. However, the basic problem with the cylindrical parabolic collector without tracking was the solar collector does not move with the orientation of sun. Development of automatic tracking system for cylindrical parabolic collectors will increase solar collection as well as efficiency of devices. The main aim of this paper is to design, fabricate and analyze the performance of parabolic collector with automated tracking system. The automated tracking mechanism is used to receive the maximum possible energy of solar radiation as it tracks the path of sun. The performance of the parabolic trough collector is experimentally investigated with the water circulated as heat transfer fluid. The collector efficiency will be noted.  相似文献   
90.
Rate of fermentation and physico‐chemical characteristics of apple wines, owing to the addition of different yeast strains, insoluble solids and pectinesterase enzyme, were examined. The highest rates of fermentation and ethanol production were found in the wine fermented by yeast strain UCD 505, while strain UCD 595 gave the smallest amount of methanol. The addition of insoluble solids to the apple juice significantly increased the levels of methanol, vitamin C, amyl alcohol, total volatiles, rate of fermentation, tannins, colour units, Mn and Zn. Addition of insoluble solids decreased pH, titrable acidity, ethanol, total sugars, total esters, and K, Mg, Ca, Cu and Fe content of the wine. Addition of pectinesterase enzyme significantly increased all the parameters examined except for pH, vitamin C, total esters, Mn and Mg content. Application of cluster analysis to the results of rate of fermentation, reducing sugars, volatile acidity and ethanol showed that the influence of the yeast strains was more than the influence of insoluble solids or pectinesterase enzyme addition. Consideration of more parameters showed that there was a clear interaction between the yeast strain, insoluble solids and the pectinesterase enzyme. Addition of insoluble solids to the must led to the production of some undesirable quality characteristics. In contrast, specific yeast strains and enzyme addition improved various physico‐chemical characteristics of the wine. Pre‐settled or clarified juice was preferred to produce a quality apple wine. Copyright © 2013 The Institute of Brewing & Distilling  相似文献   
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