Flow instabilities of liquid and mushy regions during alloy solidification and under high gravity environment induced by rotation

Linear flow instabilities of the liquid and mushy regions during directional solidification of a binary alloy are studied under a high gravity environment where the rotation axis is inclined with respect to the high gravity vector. Stability analysis and numerical computation are carried out to determine the results for the stationary disturbances at several values of the rotation rates and for given values of the other parameters. The results provide information about the effects of Coriolis force on various flow features in the liquid and mushy layers. The preferred structure of the mush-liquid interface is found to be that of longitudinal rolls. The main mode of convection is found to be able to generate double-cell structure in the vertical direction and is strengthened in the mushy layer by the Coriolis force. The Coriolis force appears to be generally stabilizing in the sense that the motion in the liquid zone is significantly weakened, the tendency for the chimney formation in the mushy zone is reduced and the critical values of the liquid and mush Rayleigh numbers and the wave number increase with increasing the rotation rate.     

核电厂功能安全措施完整性标准与第3方验证——2．核电市场化：国际标准化平台上的企业联合

在8国峰会限火电,绿色和平挺核电的2007新政治环境中与跨国核电集团优化联合的新形势下,探讨计划经济形成的两弹-艇核工业,在勃兴的市场竞争中,引进与依托在标准化平台上的本国企业大联合。     

Nonabelian statistics for calogero-sutherland systems of particles

The mathematical aspects of the theory of nonabelian statistics and anyons are discussed. The dynamics and kinematics of these objects are defined by Hamiltonians which are the sums of terms associated with different roots of a given root system. The equations of Fuchsian type which are the so-called generalized Knizhnik-Zamolodchikov equations associated with the root systemsA _n ,B _n , andC _n , are presented. Some results the generalized pure braid groups and their application for defining the generalized anyon are discussed. The factorization of the spin Calogero-Sutherland operators and their connection with the theory of nonabelian statistics and anyons are given. To Dmitrii Anosov with admiration and deep respect on his sixtieth birthday The research was supported by Grants RFFI-INTAS 00418 and RFFI-Germany 96-01-00008G.     

Role of microstructures on the growth of long fatigue cracks

An analysis is presented to understand the role of microstructures on the two crack growth driving force parameters, and , without invoking the extrinsic crack closure concepts. Microstructural variables considered are: grain size, precipitates and stacking fault energy. It is shown that is strongly affected by the scale of the microstructure, such as grain size or precipitate spacing. For each case, the mode of slip deformation and environment affects the fatigue resistance as represented by . However, the microstructures seem to have a smaller effect on . Also, the enhanced planarity of slip from the reduction in stacking fault energy has a pronounced effect on when compared with the materials deforming under homogeneous slip.     

基于解集动态分析含风电接入的多目标机组组合研究

风电的大规模接入给多目标节能减排发电调度带来了新的机遇和挑战。由于风电场出力具有随机性,采用置信区间简化风电场景模拟数量,考虑到多目标模型的复杂性,利用Benders分解技术对模型进行降维,设计一种基于解集动态分析的多目标自适应优化算法对降维后的多目标主问题进行求解,并提出一种提高模型整体求解效率的预处理机制加速收敛。仿真结果表明所提方法能够有效求解含风电的多目标机组组合问题,并验证了所提多目标算法和预处理机制在求解模型中的优势。     

The Rotation χ-Lattice of Ternary Trees

This paper generalizes to k-ary trees the well-known rotation transformation on binary trees. For brevity, only the ternary case is developped. The rotation on ternary trees is characterized using some codings of trees. Although the corresponding poset is not a lattice, we show that it is a χ-lattice in the sense of Leutola–Nieminen. Efficient algorithms are exhibited to compute meets and joins choosen in a particular way. Received May 22, 2000; revised December 11, 2000     

Degradation of polybrominated diphenyl ethers by a sequential treatment with nanoscale zero valent iron and aerobic biodegradation

BACKGROUND: Polybrominated diphenyl ethers (PBDEs) are emerging persistent organic pollutants. Degradation of PBDEs is a significant challenge owing to their extreme persistence and recalcitrance nature. The objective of this study was to evaluate the effect of a sequential nano‐bio treatment using nanoscale zero‐valent iron (nZVI) and diphenyl ether degrading bacteria Sphingomonas sp. PH‐07 for degradation of PBDEs. RESULTS: In the bacterial tolerance test for determining the maximum endurable concentration of nZVI, the PH‐07 strain was able to grow in the presence of nZVI up to 5 g L^?1 in minimal salt medium by using non‐brominated diphenyl ether as growth substrate. Reductive debromination of decabrominated diphenyl ether (deca‐BDE; 1 mg) with nZVI (100 mg per vial) resulted in a 67% reduction of deca‐BDE and produced various intermediates ranging from nona‐BDEs to tri‐BDEs during a 20 day period. Additional experiments with 2,4,4′‐tri‐BDE and 2,4,6‐tri‐BDE as initial substrates revealed that both tri‐BDEs were further debrominated to mono‐BDEs. Following the reductive debromination process, reaction mixtures were aerobically treated with DE‐grown Sphingomonas sp. PH‐07 strain to mineralize the low brominated‐DEs (tri‐BDEs—mono‐BDEs) for additional 4 days. During bacterial treatment, the low brominated‐DEs were biologically degraded to bromophenols and other prospective metabolites. CONCLUSIONS: The nZVI‐biological sequential treatment method was found to be effective for degradation of PBDEs through reductive debromination followed by biological oxidation. This hybrid treatment method may lead to the development of a remediation strategy for highly halogenated environmental pollutants in contaminated sites. Copyright © 2011 Society of Chemical Industry     

Architecture + Textiles = Architextiles

A hybrid term, ‘architextiles’ encompasses a wide range of projects and ways of thinking that unite architecture and textiles. By way of introduction to this issue, guest-editor Mark Garcia highlights the significant rise of interest in this confluence by theorists, architects, engineers, textile designers, materials scientists and artists. He also explains how, as a hybrid mode of design and practice, architextiles is better able to respond to society's fast-changing cultural and consumer demands, enabling the production of more dynamic, flexible, interactive, event and process-based spaces. Copyright © 2006 John Wiley & Sons, Ltd.