Yang C, Cai X-C. Newton-Krylov-Schwarz method for a spherical shallow water model. In: Huang Y, Kornhuber R, Widlund O, Xu J Proc. 19th International Conference on Domain Decomposition Methods (DD-19), Lecture Notes in Computational Science and Engineering. Vol. 78. Zhangjiajie, China: Springer; 2011. pp. 149–155.
Concentrations of dichlorodiphenyltrichloroethane (DDT) and its metabolites (designated as DDTs, the sum of o,p'- and p,p'-DDT, o,p'- and p,p'-DDE, and o,p'- and p,p'-DDD) in air and precipitation from the Pearl River Delta (PRD) of China were determined. Total concentrations of DDTs in air (gas + particle) and precipitation (dissolved + particle) were 170 +/- 120 pg m(-3) and 940 +/- 180 pg L(-1) for Dongguan (rural) and 240 +/- 120 pg m(-3) and 790 +/- 140 pg L(-1) for Shunde (rural), respectively, while they were 1550 +/- 640 pg L(-1) in precipitation from Guangzhou (urban). Log-transformed partition coefficients between air and particulate organic matter (log K'(oa)) of p,p'-DDT, p,p'-DDE, p,p'-DDD, o,p'-DDT, o,p'-DDE, and o,p'-DDD were 9.64 +/- 0.58, 10.07 +/- 0.56, 9.90 +/- 0.76, 10.06 +/- 0.66, 10.02 +/- 0.72, and 10.13 +/- 0.57, respectively: while those between water and particulate organic matter (log K'(om)) were 6.58 +/- 0.66, 6.36 +/- 0.53, 6.01 +/- 0.62, 6.41 +/- 0.42, 5.98 +/- 0.76, and 5.95 +/- 0.66, respectively. Total washout ratios by bulk rainfalls ranged from 4600 for o,p'-DDT to 54,000 for p,p'-DDT. Estimated average dry particle and wet depositional intensities in the PRD were 2.1 x 10(-6) and 1.6 x 10(-6) g m(-2) y(-1). (C) 2011 Elsevier Ltd. All rights reserved.
A series of conjugated oligo(p-phenylene-ethynylene) (OPE) molecules with backbone conformations (that is, the relative orientations of the contained phenylene units) controlled by competitive intramolecular hydrogen bonds to be either co-planar or random were synthesised and studied. In these oligomers, carboxylate and amido substituents were attached to alternate phenylene units in the OPE backbone. These functional groups were able to form intramolecular hydrogen bonds between neighbouring phenylene units. Thereby, all phenylene units in the backbone were confined in a co-planar conformation. This planarised structure featured a more extended effective conjugation length than that of regular OPEs with phenylene units adopting random orientation due to a low rotational-energy barrier. However, if a tri(ethylene glycol) (Tg) side chain was appended to the amido group, it enabled another type of intramolecular hydrogen bond, formed by the Tg chain folding back and the contained ether oxygen atom competing with the ester carbonyl group as the hydrogen-bond acceptor. The outcome of this competition was proven to depend on the length of the alkylene linker joining the ether oxygen atom to the amido group. Specifically, if the Tg chain folded back to form a five-membered cyclic structure, this hydrogen-bonding motif was sufficiently robust to overrule the hydrogen bonds between adjacent phenylene units. Consequently, the oligomers assumed non-planar conformations. However, if the side chain formed a six-membered ring by hydrogen bonding with the amido NH group, such a motif was much less stable and yielded in the competition with the ester carbonyl group from the adjacent phenylene unit. Thus, the hydrogen bonds between the phenylene units remained, and the co-planar conformation was manifested. In our system, the hydrogen bonds formed by the back-folded Tg chain and amido NH group relied on a single oxygen atom as the hydrogen-bond acceptor. The additional oxygen atoms in the Tg chain made a negligible contribution. A bifurcated hydrogen-bond motif was unimportant. From our results, in combination with the results from an independent study by Meijer et al.,([13]) it is evident that intramolecular hydrogen bonds involving back-folded oligo(ethylene glycol) moieties may differ in their structural details. Absorption spectroscopy served as a convenient yet sensitive technique for analysing hydrogen-bonding motifs in our study.
Gao Y, Yu H, Liu Y, Liu Y, Liu M, Zhao Y. Optimization for viewshed analysis on GPU, in Proceedings - 2011 19th International Conference on Geoinformatics, Geoinformatics 2011.; 2011. 访问链接
The interface between an electrode and the organic active layer is an important factor in organic solar cells (OSCs) that influences the power conversion efficiency (PCE). In this report, a buffer layer of 2-thenylmercaptan/Au self-assembly film is introduced into OSCs as a substitute for the poly(3,4-ethylene dioxythiophene):poly(styrene sulfonate) (PEDOT: PSS) layer. The electrode/active layer interface is meliorated by Au-S coordinate bond of self assembly after applying this buffer layer. The series resistance reduces from 20 Omega cm(2) in a device based on PEDOT:PSS to 10.2 Omega cm(2). Correspondingly, the fill factor (FF) increases from 0.50 to 0.64. Moreover, due to the dipole of this self-assembled layer, the open circuit voltage (V-oc) also increases slightly from 0.54 V to 0.56 V and the PCE reaches 2.5%. (C) 2010 Elsevier B.V. All rights reserved.