Reply to Comment on “Ewald summation technique for one-dimensional charge distributions”

We explain why the methods in Langridge, Hart and Crampin [Comput. Phys. Commun. 134 (2001) 78] suffice for the evaluation of the lattice sums entering the Madelung matrix describing multipole interactions in systems with one-dimensional translational periodicity.     

Analysis of low load transients for the Vandellòs-II NPP: Application to operation and control support

The Technical University of Catalonia (UPC) has been jointly working with the Asociación Nuclear Ascó-Vandellòs (ANAV) for a number of years in order to establish, qualify and use best estimate (BE) models for the reactors under the control of ANAV. ANAV is the consortium that is responsible for operation of the Ascó and Vandellòs-II reactors. The reactors are Westinghouse-design three-loop PWRs with an approximate electrical power of 1000 MW. The existing integral plant models for each plant are currently used for many different purposes among which are support of plant operation and control. Quite a number of studies have been done in order to improve both safety and plant competitiveness. Most of these dynamic analyses were carried out in relation to transients starting at nominal full power or at least, very close to full power. This paper develops a specific use of the Vandellòs-II plant model for operation and control support at low power involving new ranges of system actuation parameters. It also examines scenarios that are somewhat different from those typically analysed. The study starts showing the results of an assessment case, which is a start-up test and provides some additional qualification, and subsequently attempts to establish calculations to support both an improvement in feed water controls and to set up operating recommendations for low-load manual operation of feed water turbo-pump. Both results hopefully, will produce an outcome, which leads to an improvement in safety and reduces reactor trip probability.     

A comparable study of image approximations to the reaction field

The recently developed high-order accurate multiple image approximation to the reaction field for a charge inside a dielectric sphere [J. Comput. Phys. 223 (2007) 846-864] is compared favorably to other commonly employed reaction field schemes. These methods are of particular interest because they are useful in the study of biological macromolecules by the Monte Carlo and Molecular Dynamics methods.     

煤化工专用黑水阀阀座流通性能研究

介绍了一种煤化工专用黑水阀的结构构成,并提出进行该型号阀门流通性能研究的重要性。建立流道三维模型,应用CFD有限元分析软件,模拟黑水阀内部流场分布情况,分析可视化结果,确定阀座/阀芯易损位置。分别对不同阀座渐扩角时模型进行仿真模拟,得到阀门进、出口压力值,并依此计算Cv值大小,拟合流量系数曲线,提出阀门在实现最大介质流通时阀座渐扩角范围,为阀门设计提供重要的理论参考。     

USFKAD: An expert system for partial differential equations

The computation of the solution, by the separation of variables process, of the Poisson, diffusion, and wave equations in rectangular, cylindrical, or spherical coordinate systems, with Dirichlet, Neumann, or Robin boundary conditions, can be carried out in the time, Laplace, or frequency domains by a decision-tree process, using a library of eigenfunctions. We describe an expert system, USFKAD, that has been constructed for this purpose.

Program summary

Title of program:USFKADCatalogue identifier:ADYN_v1_0Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADYN_v1_0Program obtainable from: CPC Program Library, Queen's University of Belfast, N. IrelandLicensing provisions:noneOperating systems under which the program has been tested: Windows, UNIXProgramming language used:C++, LaTeXNo. of lines in distributed program, including test data, etc.: 11 699No. of bytes in distributed program, including test data, etc.: 537 744Memory required to execute with typical data: 1.3 MegabytesDistribution format: tar.gzNature of mathematical problem: Analytic solution of Poisson, diffusion, and wave equationsMethod of solution: Eigenfunction expansionsRestrictions concerning the complexity of the problem: A few rarely-occurring singular boundary conditions are unavailable, but they can be approximated by regular boundary value problems to arbitrary accuracy.Typical running time:1 secondUnusual features of the program: Solutions are obtained for Poisson, diffusion, or wave PDEs; homogeneous or nonhomogeneous equations and/or boundary conditions; rectangular, cylindrical, or spherical coordinates; time, Laplace, or frequency domains; Dirichlet, Neumann, Robin, singular, periodic, or incoming/outgoing boundary conditions. Output is suitable for pasting into LaTeX documents.     

A parallel monotone iterative method for the numerical solution of multi-dimensional semiconductor Poisson equation

Various self-consistent semiconductor device simulation approaches require the solution of Poisson equation that describes the potential distribution for a specified doping profile (or charge density). In this paper, we solve the multi-dimensional semiconductor nonlinear Poisson equation numerically with the finite volume method and the monotone iterative method on a Linux-cluster. Based on the nonlinear property of the Poisson equation, the proposed method converges monotonically for arbitrary initial guesses. Compared with the Newton's iterative method, it is easy implementing, relatively robust and fast with much less computation time, and its algorithm is inherently parallel in large-scale computing. The presented method has been successfully implemented; the developed parallel nonlinear Poisson solver tested on a variety of devices shows it has good efficiency and robustness. Benchmarks are also included to demonstrate the excellent parallel performance of the method.     

Characterization of creep-fatigue in ferritic 9Cr-1Mo-V-Nb steel using ultrasonic velocity

The microstructural evolution of ferritic 9Cr-1Mo-V-Nb steel, subjected to creep-fatigue at 550 °C, was evaluated nondestructively by measuring the ultrasonic velocity. The ultrasonic velocity was strongly depended on the microstructural changes during creep-fatigue. The variation in the ultrasonic velocity with the fatigue life fraction exhibited three regions. In the first region (within 0.2 N_f), a significant increase in the velocity was observed, followed by a slight increase between the fatigue life fractions of 0.2 N_f and 0.8 N_f and a decrease in the final region. The change of the ultrasonic velocity during creep-fatigue was interpreted in relation to the microstructural properties. This study proposes an ultrasonic nondestructive evaluation method of quantifying the level of damage and microstructural change during the creep-fatigue of ferritic 9Cr-1Mo-V-Nb steel.     

Extraction of Digoxin from Fermented Woolly Foxglove Foliage by Percolation

The present paper deals with the fermentation of chopped, dried, woolly foxglove foliage, the extraction of secondary glycosides from fermented woolly foxglove foliage by the percolation method and the isolation and purification of digoxin. Optimal process conditions for fermenting the chopped, dried, woolly foxglove foliage, extracting of digoxin from the fermented woolly foxglove foliage by percolation, and further isolating and purifying of digoxin were defined. Under the optimum anaerobic conditions for fermentation of the chopped, dried woolly foxglove foliage at 37°C, the best yield of digoxin of 99-100% was achieved in 48 h. The optimal conditions for extraction of digoxin by percolation (plant particle size: 7 mm; height of foliage in the percolator: 30 cm; extracting solvent: 10%vol. ethanol- or methanol-water solution, volumetric percolate flow rate: 4 L/h and the percolate residence time in the percolator: 4h) ensured the digoxin extraction degree of 97%. Although ethanol is currently more expensive than methanol, it is recommended as extracting solvent because of its lower toxicity. Therefore, the 10%vol. aqueous ethanol solution was recommended as the extracting solvent for recovering digoxin from the fermented woolly foxglove foliage. By further isolation and purification, a highly pure product fulfilling the requirements prescribed by pharmacopoeias was obtained.     

Effect of treatment with electrolyzed NaCl solutions and essential oil compounds on the proximate composition,amino acid and fatty acid composition of carp fillets

This investigation was undertaken to evaluate the effect of treatment with electrolyzed NaCl solutions and 1% essential oil (0.5% carvacrol + 0.5% thymol) on the proximate composition and nutritional components (amino acids and fatty acids) of carp fillets at room temperature (25 °C). Carp fillet samples were treated with anodic electrolyzed NaCl solution [EW (+)], cathodic electrolyzed NaCl solution [EW (−)] followed by EW (+) [EW (−)/EW (+)], 1% essential oil (0.5% carvacrol + 0.5% thymol) [1% (Cv + Ty)], EW (+) followed by 1% (Cv + Ty) [EW (+)/1% (Cv + Ty)] and EW (−) followed by EW (+) and finally with 1% (Cv + Ty) [EW (−)/EW (+)/1% (Cv + Ty)]. Proximate composition, SDS–PAGE, amino acid composition, digestibility and fatty acid composition were used to determine the changes in carp fillet composition. Moisture, total lipid, total protein, ash and carbohydrate contents of the carp fillets were approximately 76%, 3.9%, 17.5%, 1.0% and 0.40%, respectively. The dominant amino acid was glutamic acid, and the composition ranged from 14.2 to 14.5 mol%. Protein digestibility of the carp fillets was approximately 85%. Oleic acid was the major monounsaturated acid in the carp fillets (41.0–41.9%). These results show that our method of fish preservation, using electrolyzed NaCl solutions and 1% (Cv + Ty), did not affect the quality (nutritional components) of carp fillets, and could be a good alternative to synthetic preservatives routinely used in the food industry.