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21.
全球化下的市场竞争促使企业在全球范围进行资源整合,外包决策由此成为影响项目调度的重要因素。以三峡三期工程TCP/C1-3-1A-1项目为例,运用设计结构矩阵构建了模块化项目网络,并分两个层次对外包模块进行初选,在此基础上建立了基于模块化外包的项目调度模型。求解结果表明,由于模块化外包消除了承包商的资源瓶颈,降低了资源闲置率,并由此产生了良好的协同效应,因此可以有效地提高项目收益,并大大压缩项目工期。 相似文献
22.
Analysis of the induction of the myelin basic protein binding to the plasma membrane phospholipid monolayer
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Myelin basic protein(MBP) is an essential structure involved in the generation of central nervous system(CNS)myelin.Myelin shape has been described as liquid crystal structure of biological membrane.The interactions of MBP with monolayers of different lipid compositions are responsible for the multi-lamellar structure and stability of myelin.In this paper,we have designed MBP-incorporated model lipid monolayers and studied the phase behavior of MBP adsorbed on the plasma membrane at the air/water interface by thermodynamic method and atomic force microscopy(AFM).By analyzing the pressure–area(π–A) and pressure–time(π–T) isotherms,univariate linear regression equation was obtained.In addition,the elastic modulus,surface pressure increase,maximal insertion pressure,and synergy factor of monolayers were detected.These parameters can be used to modulate the monolayers binding of protein,and the results show that MBP has the strongest affinity for 1,2-dipalmitoyl-sn-glycero-3-phosphoserine(DPPS) monolayer,followed by DPPC/DPPS mixed and1,2-dipalmitoyl-sn-glycero-3-phospho-choline(DPPC) monolayers via electrostatic and hydrophobic interactions.AFM images of DPPS and DPPC/DPPS mixed monolayers in the presence of MBP(5 n M) show a phase separation texture at the surface pressure of 20 m N/m and the incorporation of MBP put into the DPPC monolayers has exerted a significant effect on the domain structure.MBP is not an integral membrane protein but,due to its positive charge,interacts with the lipid head groups and stabilizes the membranes.The interaction between MBP and phospholipid membrane to determine the nervous system of the disease has a good biophysical significance and medical value. 相似文献
23.
分析了我国人口城市化与房地产市场的关系,利用相关分析、因果分析、脉冲和方差分析,发现人口城市化率短期内受房地产市场影响较大,长期内房地产市场要受人口城市化速度的影响;研究了人口系统与房地产系统的熵流关系,利用静态和动态协调度定量分析,发现两个系统取得了较好协调发展效果,但未来协同效应存在下降的可能. 相似文献
24.
采用各种固体核磁共振 (NMR) 技术详细研究了 H-MCM-22 分子筛中 Brnsted/Lewis 酸的协同效应. 二维 1H 双量子魔角旋转 (DQ-MAS) NMR 结果表明, 在脱铝 H-MCM-22 分子筛中 Brnsted 酸位 (骨架桥式羟基) 和 Lewis 酸位 (非骨架铝羟基) 之间是空间邻近的, 暗示着可能存在 B/L 酸协同效应. 二维 27Al DQ-MAS NMR 结果揭示了各种铝物种之间的空间邻近性, 表明 B/L 酸协同效应优先发生在 H-MCM-22 分子筛超笼中的骨架 T6 位铝和非骨架铝物种之间. 2-13C-丙酮探针分子实验发现, 因 B/L 酸协同效应而导致脱铝 H-MCM-22 分子筛酸性明显增强, 氘代吡啶探针分子实验也证实在 H-MCM-22 分子筛的超笼中发生了 B/L 酸协同效应. 上述结果将有助于我们理解在脱铝 H-MCM-22 分子筛上发生的多相催化机理. 相似文献
25.
《Physics and Chemistry of Liquids》2012,50(3):286-301
The densities (ρ), viscosities (η), sound speeds (u) and refractive indices (n D) of seven ternary mixtures of cyclic ether (tetrahydrofuran), methanoland cyclic compounds; benzene, toluene, chlorobenzene, nitrobenzene, anisole, cyclohexane and cyclohexanone are determined over the entire range of composition at 298.15?K. From the experimental observations, viscosity deviation (Δη), the viscous synergy and antagonism, synergic and antagonic index are derived by the equations developed by Kalentunc-Gencer and Peleg [G. Kalentunc-Gencer and M. Peleg, J. Texture Stud. 17, 61 (1986)] and Howell [N.K. Howell, Presented at the Proceedings of the Seventh International Conference, Wales, 1993], respectively. Excess molar volume (V E), excess isoentropic compressibility (ΔK S) and excess molar refraction (ΔR) have been calculated from the experimentally measured density, sound speed and refractive index values. The excess Gibb's free energy of activation (ΔG E) has also been calculated. The results are discussed and interpreted in terms of molecular package and specific interaction predominated by hydrogen bonding. 相似文献
26.
In this contribution, we specify the conditions for assuring the validity of the synergy of the distribution of probabilities of occurrence. We also study the subsequent restriction on the maximal extension of the strict concavity region on the parameter space of Sharma–Mittal entropy measures, which has been derived in a previous paper in this journal. The present paper is then a necessary complement to that publication. Some applications of the techniques introduced here are applied to protein domain families (Pfam databases, versions 27.0 and 35.0). The results will show evidence of their usefulness for testing the classification work performed with methods of alignment that are used by expert biologists. 相似文献
27.
The selection abilities of the two well‐known techniques of variable selection, synergy interval‐partial least‐squares (SiPLS) and genetic algorithm‐partial least‐squares (GA‐PLS), have been examined and compared. By using different simulated and real (corn and metabolite) datasets, keeping in view the spectral overlapping of the components, the influence of the selection of either intervals of variables or individual variables on the prediction performances was examined. In the simulated datasets, with decrease in the overlapping of the spectra of components and cases with components of narrow bands, GA‐PLS results were better. In contrast, the performance of SiPLS was higher for data of intermediate overlapping. For mixtures of high overlapping analytes, GA‐PLS showed slightly better performance. However, significant differences between the results of the two selection methods were not observed in most of the cases. Although SiPLS resulted in slightly better performance of prediction in the case of corn dataset except for the prediction of the moisture content, the improvement obtained by SiPLS compared with that by GA‐PLS was not significant. For real data of less overlapped components (metabolite dataset), GA‐PLS that tends to select far fewer variables did not give significantly better root mean square error of cross‐validation (RMSECV), cross‐validated R2 (Q2), and root mean square error of prediction (RMSEP) compared with SiPLS. Irrespective of the type of dataset, GA‐PLS resulted in models with fewer latent variables (LVs). When comparing the computational time of the methods, GA‐PLS is considered superior to SiPLS. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
28.
In this work two aluminic pozzolans (metakaolins) and a non-pozzolan were added to two Portland cements with very different
mineral composition, to determine the effect on the rate of heat release and the mechanisms involved. The main analytical
techniques deployed were: conduction calorimetry, pozzolanicity and XRD.
The results showed that the two metakaolins induced stimulation of the hydration reactions due to the generation of pozzolanic
activity at very early stage, because of their reactive alumina, Al2O3r− contents, mainly. Such stimulation was found to be more specific than generic for more intense C3A hydration than C3S, at least at very early on into the reaction, and more so when 7.0% SO3 was added, and for this reason, such stimulation is described as ‘indirect’ to differentiate it from the ‘direct’ variety.
As a result of both stimulations, the heat of hydration released is easy to assimilate to a Synergistic Calorific Effect. 相似文献
29.
30.
用隐含5点模式对二维Fokker-Planck方程进行离散化,调用NAG程序库中子函数D03UAF求解该方程,并将求解二维Fokker-Planck方程的code与波的射线轨迹code相结合,根据HT-7托卡马克装置参数,分别对有或没有IBW情况下的等离子体电流的全波驱动和在低杂波和离子伯恩斯坦波协同作用下低杂波的功率沉积分布、驱动电流分布等进行数值模拟研究.结果显示:有IBW情况下的全波驱动电流分布比没有IBW时全波驱动的电流分布区域要广一些,而且驱动的总电流也大一点;在双波协同作用下,全波驱动的等离子体电流空间分布随IBW的频率和n//谱的变化而变化;在两波协同作用下低杂波驱动非感应电流的效率得到了很大的改善. 相似文献