Conformation and electrical conductivity of poly(γ-methyl-L(LD)-glutamates) reticulate-doped with 1,3-dimethylimidazolium-7,7,8,8-tetracyano-p-quinodimethane complex salt

Polymeric composites were prepared by reticulate doping of poly(γ-methyl-L-glutamate) (PMLGA) and poly(γ-methyl-LD-glutamate) (PMLDGA, 1 : 1) having different conformation forms with 1,3-dimethylimidazolium-TCNQ complex salt. The heat induced α-helix to coil transition in PMLGA and α-helix to β-form and coil transition in PMLDGA were carried out in chlorobenzene and o-dichlorobenzene at temperatures between 70 and 150°C. The conductivity of polyglutamate composites thermally treated and prepared at 70°C is higher by approximately two orders of magnitude than that of thermally not treated films cast at ambient temperature. The conductivity of the most conductive reticulate-doped PMLGA film is higher by more than four orders of magnitude than that of the 1,3-dimethylimidazolium-TCNQ complex salt in pressed pellets.     

Some metallurgical observations upon the Preparation of Zircaloy 2/Stainless Steel Joints

A method of welding stainless steel to Zircaloy 2 by co-extrusion is proposed, and joints of these two metals have been made in this manner. Such a bond was examined at the interface between stainless steel and Zircaloy 2 using metallography, electron microprobe analysis, scanning electron microscopy and chemical analysis. It was found that this method of preparation the joints allow for sound connections characterized by the formation of a type of mechanical and metallurgical bond. These joints could be considered better than those obtained by diffusion at high temperatures.     

The influence of monoacylglycerol and L‐glutamic acid on the viscoelastic properties of wheat flour dough and sensory characteristics of French loaf product

BACKGROUND: The influence of monoacylglycerol Rimulsoft Super(V) and L ‐glutamic acid added to wheat flour dough was studied. Properties of the doughs were evaluated on the basis of chemical analysis and rheological measurements on a farinograph. Bakery products made from these doughs were subsequently subjected to sensory analyses. RESULTS: It was found that L ‐glutamic acid influenced the water absorption in dough more (50.0 g kg^?1; water absorption 56.6%) than monoacylglycerol Rimulsoft Super(V) (50.0 g kg^?1; water absorption 55.0%). Farinograph measurements showed that doughs with the addition of L ‐glutamic acid resembled flour containing high‐quality gluten, but dough with the addition of monoacylglycerol Rimulsoft Super(V) corresponded to ‘weak’ flour. Sensory analyses revealed that, in comparison with the control sample of French loaf, the saliva‐absorbing capacity increased in the French loaf with the highest addition of L ‐glutamic acid (30.0 g kg^?1). Deterioration in quality and texture in French loaf with addition of L ‐glutamic acid (8.0 g kg^?1, 30.0 g kg^?1) was noted. No other statistically significant differences were found. CONCLUSION: It is acceptable to add both additives to dough in order to modify its rheological properties. Copyright © 2010 Society of Chemical Industry     

Behavior of Deformed Droplets in an Immiscible Polymer Blend: A Comparative Study of Electron Microscopy and Small‐Angle X‐Ray Scattering

The deformation of dispersed droplets in a PS/LLDPE 95:5 blend during uniaxial elongation and after cessation of the flow was studied. The behavior of the dispersed droplets during elongation is in a good agreement with a prediction of the modified capillary number model using transient elongational viscosities. The phase structure changes after the elongation was studied in relaxation and recovery modes. The morphology was investigated using scanning electron microscopy and small‐angle X‐ray scattering. Thus the dimensions of the dispersed particles and their degree of orientation were estimated. It was shown that the SAXS as an integral method gives new additional information which is hardly accessible by SEM as a method providing local information about discrete locations in the sample. The results of both methods proved that the stress in the sample is a decisive parameter determining the morphology development after cessation of the flow.

     

A formal approach to AADL model-based software engineering

International Journal on Software Tools for Technology Transfer - Formal methods have become a recommended practice in safety-critical software engineering. To be formally verified, a system should...     

A selective organosilica membrane for ethyl acetate dehydration by pervaporation

Organosilica bis(triethoxysilyl) ethane (BTESE) membranes were explored for pervaporation dehydration of binary and ternary mixtures of ethyl acetate (EA) by undiluted sol coating combined with flash firing. Three BTESE membranes (M1, M2, and M3) were fabricated on macroporous supports by varying BTESE concentrations (0.5, 2.5, and 5 wt% BTESE, respectively) in polymer sols. The membranes were characterized by DLS, SEM, FTIR, XRD, contact angle, AFM, and pervaporation performance to discuss the effect of the BTESE contents in the polymer sol on the formation and dehydration performance of resulting organosilica membranes. It was found that 5 wt% loading of BTESE led to a highly selective membrane for dehydration of EA/H₂O mixture. Among the synthesized membranes, M3 delivered flux of 0.84 ± 0.05 kg.m⁻².h⁻¹ with a selectivity of >10,000 for EA/H₂O mixture (98/2 wt%) at 60°C. The time course of pervaporation dehydration for the EA/H₂O mixture (95/5 wt%) confirms the stability of BTESE membrane in the investigated time period of 120 h. Further, the membrane exhibited excellent selectivity larger than 10,000 for separation of ternary mixtures (90/2/8 wt%) of ethyl acetate/ethanol/water and n-propyl acetate/isopropanol/water respectively, the composition of which is similar to the top product of the distillation column used in the industrial esterification process. The best separation performance and excellent acid stability of BTESE membranes in this study suggest that the simple synthesis protocol of undiluted sol coating and flash firing will provide a cost-effective, quick, and efficient synthesis route for practical membrane based applications.     

Integrative and multi-disciplinary framework for the 3D rehabilitation of large mandibular defects

The International Journal of Advanced Manufacturing Technology - The restoration of mandibular defects, especially large deformities is regarded as the most challenging surgical procedure owing to...