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901.
The original BML model is extended by introducing extended sites, which can hold several vehicles at each time-step. Unexpectedly, the flow in the extended model sharply transits from free-flow to global jams, but the transition is not one-order in original BML model. And congestion in the extended model appears more easily. This can ascribe to the mixture of vehicles from different directions in one site, leading to the drop-off of the capacity of the site. Furthermore, the typical configuration of free flowing and global jams in the extended models is disorder, different from the regular structure in the original model.  相似文献   
902.
Both surface tension and solubility parameter are decided by molecular interactions. There are several empirical equations describing their connection. However, at least two limitations exist for them: polymers cannot be treated and only apolar or weakly polar solvents can be fitted. We found when only the dispersive properties were considered, for 37 solvents and 22 polymers, a linear relationship exists between γ d and γ/δ2/3 d , fitted by a new equation. Compared with the previous equations, the value of the new equation is that most solvents and common polymers could be treated simultaneously. This equation will be of value for estimating the accuracy of reported surface tension data or solubility parameters of polymers.  相似文献   
903.
Benzyl sulfonamide/alcohol‐tethered alkylidenecyclopropanes undergo a rhodium‐catalyzed and substrate‐controlled selective C?C bond activation, producing three types of common organic structural units: benzo[c]azepine/oxepines, dihydronaphthalen‐1‐amines, and conjugated dienes. Epoxidation and aromatization of these products to construct two useful compounds have also been achieved.  相似文献   
904.
For the first time, the influence of different types of atoms (Zn and O) on the antibacterial activities of nanosized ZnO was quantitatively evaluated with the aid of a 3D‐printing‐manufactured evaluation system. Two different outermost atomic layers were manufactured separately by using an ALD (atomic layer deposition) method. Interestingly, we found that each outermost atomic layer exhibited certain differences against gram‐positive or gram‐negative bacterial species. Zinc atoms as outermost layer (ZnO?Zn) showed a more pronounced antibacterial effect towards gram‐negative E. coli (Escherichia coli), whereas oxygen atoms (ZnO?O) showed a stronger antibacterial activity against gram‐positive S. aureus (Staphylococcus aureus). A possible antibacterial mechanism has been comprehensively discussed from different perspectives, including Zn2+ concentrations, oxygen vacancies, photocatalytic activities and the DNA structural characteristics of different bacterial species.  相似文献   
905.
Using vacuum evaporation and sputtering process, we prepared a photoelectric transistor with the vertical structure of Cu/copper phthalocyanine (CuPc)/Al/copper phthalocyanine (CuPc)/ITO. The material of CuPc semiconductor has good photosensitive properties. Excitons will be generated after the optical signal irradiation in semiconductor material, and then transformed into photocurrent under the built-in electric field formed by the Schottky contact, as the organic transistor drive current makes the output current enlarged. The results show that the I–V characteristics of transistor are unsaturated. When device was irradiated by full band (white) light, its working current significantly increased. In full band white light, when Vec = 3 V, the ratio of light and no light current was ranged for 2.9–6.4 times. Device in the absence of light current amplification coefficient is 16.5, and white light amplification coefficient is 98.65.  相似文献   
906.
907.
908.
909.
采用分子蒸馏法对树苔浸膏进行分级分离,用气相色谱-质谱法对各级馏分进行定性和定量分析。结果表明:三级馏分共鉴定出55种成分,主要成分是苔黑酚单甲醚、分歧扁枝衣素单甲醚、扁枝衣酸乙酯、柔扁枝衣酸甲酯、β-苔黑酚羧酸甲酯、赤星衣酸乙酯、苔黑酚羧酸乙酯、柔扁枝衣酸乙酯、棕榈酸乙酯、油酸乙酯、亚麻酸乙酯和亚油酸乙酯。  相似文献   
910.
There is a delicate balance for a low‐weight molecule to behave as a gelator or crystal. The synthesis of two novel amino acid‐based naphthalene‐dendrons, Nap ‐ G1 and Nap ‐ G2 is described. Both dendrons display polymorphic properties in organic solvents. Nap ‐ G1 developed a fibrous network with β‐sheet architecture in cyclohexane but exhibited a spherulitic network in mixed solvents (chloroform/petroleum ether 1:5, v/v). On the other hand, Nap ‐ G2 acted as an efficient organogelator in chloroform but formed crystalline fibers in relatively high polarity solvents (such as acetone and methanol). Combinations of characterizations have been employed to study the polymorphism.  相似文献   
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