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991.
Liuhua ChenLihua Gan Mingxian LiuRong Fan Zijie XuZhixian Hao Longwu Chen 《Applied Surface Science》2011,257(11):5070-5076
The effect of tryptophan on the membrane stability was studied by using three artificial biological membranes including liposome, Langmuir monolayer and solid supported bilayer lipid membrane (s-BLM) as models. All the results indicate that the penetration of tryptophan can destabilize different artificial biological membranes. The diameter of liposome and the leakage of calcein from liposome increased with the increase of tryptophan concentration because the penetration of tryptophan was beneficial for dehydrating the polar head groups of lipids and the formation of fusion intermediates. π-A isotherms of lecithin on the subphase of tryptophan solution further confirm that tryptophan can penetrate into lipid monolayer and reduce the stability of lipid monolayer. When the concentration of tryptophan increased from 0 to 2 × 10−3 mol L−1, the limiting molecular area of lecithin increased from 110.5 to 138.5 Å2, but the collapse pressure of the monolayer decreased from 47.6 to 42.3 mN m−1, indicating the destabilization of lipid monolayer caused by the penetration of tryptophan. The resistance spectra of s-BLM demonstrate that the existence of tryptophan leads to the formation of some defects in s-BLM and the destabilization of s-BLM. The values of electron-transfer resistance and double layer capacitance respectively decreased from 5.765 × 106 Ω and 3.573 × 10−8 F to 1.391 × 106 Ω and 3.340 × 10−8 F when the concentration of tryptophan increased from 0 to 2 × 10−3 mol L−1. Correspondingly, the breakdown voltage of s-BLM decreased from 2.51 to 1.72 V. 相似文献
992.
Previously the perihelion advance in binary system was computed approximately. We will present an exact analytical solution
to nonlinear differential equation of perihelion advance by method of Jacobian elliptic function and the advanced angle between
successive perihelions.
Project supported by the Scientific Research Foundation for the Returned Overseas Chinese Scholars from Ministry of Education,
China (Grant No. [2004]527) and the Natural Science Foundation of Hunan Province, China (Grant No. 06JJ2026) 相似文献
993.
<正>A novel caged-prenylxanthone xanthone,neobractatin(1),was isolated from the twig of Garcinia bracteata.Its structure was elucidated by spectroscopic methods,especially 2D NMR techniques. 相似文献
994.
研究源自于MapReduce系统的一类排序问题。给定两台恒速机和一组按列表到达的工件,每个工件包含两类任务:Map Task和Reduce Task。假设Map任务和Reduce任务都是不可中断的,Map任务可以并行处理,即可以任意分割成若干小的任务并在两台机器上同时处理,而Reduce任务只可以在单台机器上处理。一旦工件到达,必须为其指派机器和开工时间,目标是使得最后完工时间最小。对LSc算法的竞争比进行了分析,得到其一般情形下的竞争比当$s\geq(1+\sqrt{5})/2$时为$1+1/s$,否则为$1+s/(s+1)$。而当每个工件$J_j$都满足其Map任务总长大于等于Reduce任务总长时,其竞争比当$s\geq(1+\sqrt{3})/2$时不超过$1+1/(2s)$,否则为不超过$1+s/(2s+1)$。 相似文献
995.
Chen Peng Liang Xiaoping Wang Jun Zhang Di Yang Shanmin Wu Weishan Zhang Wei Fan Xiaowei Zhang Dequan 《Journal of Sol-Gel Science and Technology》2017,81(3):850-858
Journal of Sol-Gel Science and Technology - To develop high performance mixed matrix gel polymer electrolyte, the synergistic effect of blending PVDF (PEO/PVDF weigh ratio of 85:15) and adding... 相似文献
996.
Xinying Zhang Xiaoyan Li Xuesen Fan Xia Wang Dongfang Li Guirong Qu Jianji Wang 《Molecular diversity》2009,13(1):57-61
One-pot multi-component reactions of aldehydes, cyanothioacetamide and malononitrile promoted by ionic liquid proved to be
an efficient way for the synthesis of thiopyran derivatives. Without any added catalyst, both aromatic and aliphatic aldehydes
participated in this reaction smoothly. As an application of this method, a pyrimidine nucleoside-thiopyran chimera with potential
biological activities was obtained in high yield from 5-formyl-2’-deoxyuridine. In addition, the ionic liquid used can be
easily recovered and effectively reused for at least 5 times.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
997.
Tianyu Sun Jianyong Ma Xiaoyong Fu Jianpeng Wang Yunxia Jin Jianda Shao Zhengxiu Fan 《中国光学快报(英文版)》2010,(5):447-448
<正>A guided-mode resonance(GMR) filter with the same material(Ta_2O_5) for both the grating layer and the waveguide layer is designed and fabricated.This simple structure is easy to fabricate and can avoid the defects at the grating/waveguide interface using different materials.The spectral response measured with a Lambda 900 spectrophotometer under normal incidence for TE waves exhibits a peak reflectance exceeding 80%at the wavelength of 1040 nm with a full-width half-maximum(FWHM) linewidth of 23 nm.We evaluate the deviations of the fabricated structure from the designed parameters. 相似文献
998.
<正>The optical performance of thin film polarizers is highly sensitive to the layer thicknesses of thin film.The thicknesses of the sensitive layers are optimized in order to gain broader polarizing zone in such case when the total layer thickness does not increase.An automatic layer thickness control system is established,and errors caused by different monitoring methods are analyzed.With this thickness control system,thin-film polarizers with T_p higher than 98%and T_p/T_s higher than 200:1(T_p and T_s are transmissions for p- and s-polarizations,respectively) with the bandwidth of 11 nm are prepared.Using the system allows for optimum repeatability of three successive runs. 相似文献
999.
<正>SnO_2 nanorods were deposited on the Si substrates in an aqueous solution containing both SnCl_4 and CO(NH_2)_2.It is found that different self-assembled patterns of SnO_2 nanorods can be obtained by changing the deposition conditions such as the molar ratio of CO(NH_2)_2 to SnCl_4 and the pretreatment of the substrate.Scattered SnO_2 nanorods,for example,can be changed into flower-like patterns when the molar ratio of CO(NH_2)_2 to SnCl_4 is raised,and well-aligned nanorod arrays can be formed when the pretreatment of the substrate is changed.In addition,some interesting patterns,e.g.tree-like patterns,can also be observed. 相似文献
1000.
In this paper, the hinged road-mat construction is modeled as a cable structure, and based on the equivalent cable theory the sinkage of the roadway is evaluated. Neglecting details of the interaction between tires and road mats, works caused by the traction, resistance, and drawbar pulling are defined to build a new work criterion to evaluate the mobility of vehicles on the hinged road mats. Mobility diagrams, related to coefficient of adhesion, terrain deformation, beam width, and fastening force, are developed to evaluate the locomotion of vehicles and further guide the design of hinged road mats. The presented method compares well with the field terramechanical experiments of the hinged road mats, thus verifying the validity of equivalent cable modeling and work criterion for hinged road mats. 相似文献