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91.
A bis-phenylethynyl thiophene derivative functionalized with long-chain pyridyl biscarboxamides displayed unique helical morphology in the xerogel form via nicely complementary intermolecular interactions. The helical nanostructures visualized by TEM and AFM remarkably matched well with the computational results. Supramolecular chirality can be amplified by coassembly of a chiral conductor to bias the helical arrangement. 相似文献
92.
93.
CHRISTINE R
CKMANN UWE A. SCHNEIDER MICHAEL A. ST. JOHN RICHARD S.J. TOL 《Natural Resource Modeling》2007,20(2):223-262
ABSTRACT. . The population dynamics of the Eastern Baltic cod (Gadus morhua callarias L.), unlike many other stocks, shows a strong dependency on environmental conditions. To test the implications of different management policies on the stock and the fishery in a system of global environmental change, we apply a spatially disaggregated, discrete time, age‐structured model of the Eastern Baltic cod stock in 50 year simulation analyses. The simulation provides an analysis of stock, yield, and revenue development under various management policies and environmental scenarios. The policy analysis, focusing on different regulations of fishing mortality, is embedded into three environmental scenarios, assuming low, medium, or high climate and environmental change. The environmental assumptions are based on simulation results from a coupled atmosphere‐ocean regional climate model, which project salinity in the Baltic Sea to decrease by 7–47% in the period 2071–2100 relative to the reference period 1961 1990. Our simulation results show that a significant reduction in fishing mortality is necessary for achieving high long‐term economic yields. Moreover, under the environmental scenarios presented, a stock collapse cannot be prevented. It can, however, be postponed by the establishment of a marine reserve in ICES subdivision 25. 相似文献
94.
In this paper we consider defective products and Taguchi’s cost of poor quality in the economic order quantity (EOQ) model. We assume that the product quality performs a normal distribution function, and the Taguchi’s poor quality cost has been involved. From our analysis, it has been found that the annual profit will be decreased if the poor quality of product and Taguchi’s quality cost are involved in the model. It has also been found that economic order quantity in our model is larger than that in a traditional EOQ model. 相似文献
95.
Structural Diversity in the Self‐assembly of Cd(II) Complexes Containing 2,6‐Dimethyl‐3,5‐dicyano‐4‐(4‐pyridyl)‐1,4‐dihydropyridine
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The syntheses, structures and properties of the complexes [CdBr2( L )2·4H2O]n [ L = 2,6‐dimethyl‐3,5‐dicyano‐4‐(4‐pyridyl)‐1,4‐dihydropyridine], 1 and [Cd(SCN)2( L )2(H2O)]n, 2 , are reported. In polymeric complexes 1 — 2 , the L ligands bridge the metal centers through the pyrimidyl and cyano nitrogen atoms forming 1‐D double‐stranded chain and zigzag chain, respectively. The L ligands in complex 1 act as κ1, κ1‐bidentate bridging ligand, whereas the L ligands in complex 2 act as κ1‐monodentae and κ1, κ1‐bidentate bridging ligand. The molecules of these complexes are interlinked through various weak interactions that form the packed structure. All the complexes exhibit emissions which may be tentatively assigned as intraligand (IL) π→π* transitions. 相似文献
96.
97.
The effects of baryon exchanges in the renormalisation of Regge trajectories are studied in the dual unitarisation scheme. The main results are that: (i) the pomeron is boosted above α = 1, giving rising total cross sections beyond baryon-antibaryon thresholds, and (ii) the ω trajectory remains approximately at α = 0.5 but acquires a sizeable admixture of the exotic state, which enhances its coupling to baryons. There are in addition a number of other interesting predictions. 相似文献
98.
Sheung Tsun Tsou 《Nuclear Physics B》1978,141(4):397-412
Using a quark-gluon model we study exhaustively the states with , where at least one q is a strange quark. The spectrum is extremely rich, but a few trajectories are singled out by their distinctive decay pattern and production mechanism. States of unusual colour content, formed from a diquark in colour-6 and an antidiquark in , are weakly coupled to or two-meson channels through decay. Instead they prefer to cascade by emitting a π or a K if possible. Narrow states among these are expected to be seen in Kp interactions. States with S = 2 will occur with final states, but not for example . Some of these can be produced diffractively, with cross sections in the region of 1 μb. Those that require quantum-number exchange for production are expected to have considerably lower cross sections. Some can occur as cascade decay products. 相似文献
99.
This paper is concerned with the study of certain stabilityproperties of discrete-time systems by means of topologicalmethods. It turns out that suitably defined sets guarantee thestability of the reachable sets in the vicinity of compact sets.Furthermore, special properties about affine control systemsare given. 相似文献
100.