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81.
Jinming Lyu Paul G. Chen Gwenn Boedec Marc Leonetti Marc Jaeger 《Comptes Rendus Mecanique》2018,346(6):439-448
The red blood cell (RBC) membrane is a composite structure, consisting of a phospholipid bilayer and an underlying membrane-associated cytoskeleton. Both continuum and particle-based coarse-grained RBC models make use of a set of vertices connected by edges to represent the RBC membrane, which can be seen as a triangular surface mesh for the former and a spring network for the latter. Here, we present a modeling approach combining an existing continuum vesicle model with a coarse-grained model for the cytoskeleton. Compared to other two-component approaches, our method relies on only one mesh, representing the cytoskeleton, whose velocity in the tangential direction of the membrane may be different from that of the lipid bilayer. The finitely extensible nonlinear elastic (FENE) spring force law in combination with a repulsive force defined as a power function (POW), called FENE–POW, is used to describe the elastic properties of the RBC membrane. The mechanical interaction between the lipid bilayer and the cytoskeleton is explicitly computed and incorporated into the vesicle model. Our model includes the fundamental mechanical properties of the RBC membrane, namely fluidity and bending rigidity of the lipid bilayer, and shear elasticity of the cytoskeleton while maintaining surface-area and volume conservation constraint. We present three simulation examples to demonstrate the effectiveness of this hybrid continuum–coarse-grained model for the study of RBCs in fluid flows. 相似文献
82.
83.
红层泥岩水岩作用特征研究 总被引:13,自引:0,他引:13
红层是红色陆相沉积为主的碎屑沉积岩层,岩性以砂岩、泥岩、粉砂岩和页岩为主。该类岩层多为软岩与硬岩相间,呈互层状产出,层间结合力弱。受区域构造影响,岩层扭曲褶皱强烈,多中高倾角,结构面发育,有泥化现象。红层中的泥岩具有透水性弱、亲水性强,遇水易软化、塑变,抗风化能力弱,易崩解等特性。特别是遇水后岩体及结构面抗剪强度大幅度降低,并且具有遇水膨胀、失水收缩的工程特性。水岩作用对边坡的影响主要有,结构面遇水泥化导致楔形体失稳,泥岩塑性变形引起边坡蠕变,同时红层还具有很强的崩解性,边坡开挖后发生崩解等现象。 相似文献
84.
The facility characteristics for irradiation of red meat and poultry differ significantly from those of medical disposables. This paper presents the results of the market requirement definition which resulted in an innovative conceptual design. The process and the “state of the art tools” used to bring this abstract idea into a proof of concept are presented. 相似文献
85.
Sharifuddin Mohd Zain Rauzah Hashim Alan G. Taylor David Phillips 《Journal of Molecular Structure》1997,401(3):287-300
The electronic structures of carbazole, N-phenylcarbazole (NPC), cyanophenylcarbazole (CPC) and N-ethylcarbazole (NEC) have been calculated using the quantum chemical semi-empirical MINDO/3 method. In this paper, electronic ground states and first singlet excited states of the systems mentioned were investigated. It is observed that the excitation energy of carbazole based on the calculated difference in heats of formation agrees quite well with experimental data obtained from supersonic expansion studies. Calculated energy levels of molecular orbitals and their graphical forms are used qualitatively in elucidating the S0 → S1 excitation electronic origin red shifts observed in carbazole derivatives with respect to the electronic origin of the parent carbazole. It is noted that the red shifts are not just a result of the destabilization of the HOMO of carbazole but are also determined by the nature of the substituting moieties. It is also observed that the LUMO of CPC is not derived from the parent carbazole which partially explains the difference in electronic behaviour as compared with the other derivatives. 相似文献
86.
87.
Ling Zhang Chunyong Li Dehua Li Pingxue Li Qiulin Zhang Zhiguo Zhang 《Optics & Laser Technology》2005,37(7):524-526
A design of diode-pumped high efficiency Nd:YVO4/LBO laser with a compact linear cavity was reported. Employing a type-II noncritical phase-matched LBO crystal, we generated 520 mW of 671 nm in single transverse mode at 6 W of incident pump power, the optical conversion efficiency being 8.7%. 相似文献
88.
89.
Determination of chlorophenols in red wine using ionic liquid countercurrent chromatography as a new pretreatment method followed by high‐performance liquid chromatography 下载免费PDF全文
A countercurrent chromatography method for the enrichment and cleanup of chlorophenols from food samples was successfully established by using an ionic‐liquid‐modified two‐phase solvent system composed of dichloromethane containing 2% 1‐butyl‐3‐methylimidazolium bis(trifluoromethanesulfonyl)imide and water. The column was firstly filled with the organic stationary phase, and then a large volume of sample was pumped into the column after it was equilibrated with pure water at the rotation speed. Finally, the trace amounts of chlorophenols extracted and enriched in the stationary phase were eluted out by an alkaline mobile phase and determined by high‐performance liquid chromatography. Under optimized conditions, the enrichment and cleanup of the chlorophenols can be fulfilled online with enrichment factors (34–65) and high recoveries (84.69–95.23%). The method has been applied to the determination of chlorophenols in real red wine samples with the limits of detection in the range of 1.89–4.21 μg/L. The present method is highly suitable for the pretreatment of large volume of aqueous sample for the determination of trace amounts of contaminants in food and environmental samples. 相似文献
90.
Textile wastewater shows great threats to the environment if not well pretreated before discharge. A promising technique, ozonation, was applied to remove the color in dye solutions containing C.I. Reactive Red 195 (RR195) in a semi-batch reactor. The decolorization of RR195 by the ozone process followed pseudo-first-order kinetics. Several factors which influenced the efficiency of decolorization were studied and the reaction rate constant (k) obtained with different operational parameters was compared. Our results showed that RR195 was more easily degraded in acidic than in alkaline conditions. The dyeing auxiliaries (sodium carbonate and sodium chloride) that acted as radical scavengers could enhance the decolorization process, and the ozonation time for total color removal lengthened if the initial dye concentration was higher. The analysis of the ozonation products was performed by liquid chromatography-tandem mass spectrometer and a possible degradation pathway was predicted according to the ozonation products and structure of RR195. Our results indicated that ozonation was effective in the color removal of dyes, but further treatment might be necessary since the ozonation products are high toxic. 相似文献