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We developed a method for determination of motor conduction along the mandibular and sensory conduction along the lingual and inferior alveolar nerves in 10 controls and 6 patients with lingual neuropathy following lower wisdom tooth extraction. Patients with lingual neuropathy had reduced/absent or delayed compound sensory action potentials and normal conduction along the fibers of the inferior alveolar nerve and mandibular nerve. The method provides a useful electrophysiological means of evaluating lingual nerve lesions. 相似文献
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Synthesis of Chlorinated and Non-chlorinated Polyols from Model Cross-Metathesis Modified Triacylglycerols
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Prasanth K. S. Pillai Shaojun Li Laziz Bouzidi Suresh S. Narine 《Journal of the American Oil Chemists' Society》2017,94(1):133-147
Three pure triacylglycerols (TAG) containing decenoic acid (D), and stearic acid (S), were hydroxylated into chlorinated and non-chlorinated polyols and studied in detail. D is a fatty moiety that can result from the cross metathesis of small olefins with common vegetable oils such as soybean oil. A fundamental understanding relating chemical composition and derived structure, particularly the number and position of the hydroxyl groups, to physical properties was established allowing us to add some perspective to the growing body of knowledge on industrially relevant polyol and polyurethane systems produced with metathesis-modified TAG (MTAG). The hydroxyl value, crystallization and melting behaviors, thermal degradation behavior of the polyols were directly related to their peculiar shortened and primary functionality inherited from the parent MTAG. The effect of regiochemistry on the physical properties of the polyols was investigated with the chromatography fractions of the trichlorinated polyol of propane-1,2,3-triyl tris(dec-9-enoate), giving an unhindered insight into the role of short and terminal functionality of MTAG polyols that will help select the optimal isomer composition for designer polyurethane materials. 相似文献
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Virtual adjustable sources are introduced in equivalent network representation of boundary conditions. For this purpose, integral equations are to be solved simple application of analog Kirchoff’s and Ohm’s laws. These adjustable sources represent generalized trial quantities. In order to illustrate this proposed approach, equivalent network representation of lossy planar transmission lines with arbitrary metallization thickness is presented. 相似文献
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The derivation of integral equations for solving boundary conditions by mere application of analog Kirchhoff's and Ohm's laws is used. Generalized trial quantities are introduced as virtual adjustable sources in the equivalent network representation of boundary conditions. The lossy conductor domain of a planar transmission line is represented by a particular two-port. Thus, metallic losses can be evaluated for any metallization thickness without restricting the conductor modeling to a simple surface impedance approximation. In this paper, this two-port model is discussed and numerical results relative to a lossy coplanar waveguide (CPW) are presented. These results are in very good agreement with those obtained from the mode-matching technique and with other experimental data available in the literature. The size of matrices involved in the calculation of losses is twice as large as that in the lossless case. Moreover, the authors' formulation can be easily applied to superconducting planar transmission lines 相似文献
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Kosheela D. Poopalam Latchmi Raghunanan Laziz Bouzidi Shoot Kian Yeong Suresh S. Narine 《国际能源研究杂志》2019,43(13):6934-6950
One of the major shortcomings of current organic phase change materials (PCMs) is their relatively low melting points, typically below 80°C, which limits their integration into thermal energy storage (TES) systems. The present work was aimed at developing lipid‐derived PCMs with increased melting points which would be suitable for TES applications requiring higher melting points without compromising other key properties such as enthalpy. The introduction of an amide group into the structure of linear saturated fatty acids was used as a means to increase intermolecular interactions and therefore crystallization and melting points. A series of six linear monoamides with differing chain length and symmetry about the amide group were investigated for thermal stability, thermal transition, flow behavior, and crystal structure to establish the structure‐property relationships relevant to TES. The presence of the highly polar amide group in the aliphatic fatty acid–derived molecules resulted in notable improvement in performance compared with the analogous monofunctional molecules: Increases in melting points (79°C‐96°C) and high enthalpies of fusion (155‐201 J/g) were recorded. Fundamental relationships between structure, processing, and macroscopic physicochemical properties, never before elucidated, were revealed in the study. The study revealed a step‐like variation of macroscopic properties: a surprising outcome of the competition between intermolecular attractions, symmetry effects, and mass transfer limitations. The predictive structure‐function relationships established in this work will allow the straightforward engineering of monoamide architectures that can extend the range of organic PCMs and deliver thermal properties desirable for TES applications. 相似文献
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Mark Baker Laziz Bouzidi Nissim Garti Suresh S. Narine 《Journal of the American Oil Chemists' Society》2014,91(4):559-570
Positional isomerism in triacylglycerols (TAG), present in a molecular ensemble arising from genetic, environmental or processing-induced changes, can result in significant differences in the macroscopic physico-chemical functionality of crystallized networks of the ensemble. The differences in phase behavior induced by positional isomerism and levels of unsaturation of pure oleoyl-distearoyl TAG (SOS, SSO) were detailed at different length scales. The effect of cooling rate on the polymorphism, thermal properties and microstructure were systematically investigated between 0.1 and 5 °C/min. The symmetrical SOS presented a complex polymorphism and microstructure, which varied predictively with cooling rate. The crystal phases and transitions observed for this TAG are similar to those of cocoa butter. In contrast, the cooling rate had limited effect on the phase behavior of the asymmetrical SSO. The differences between the crystallization of SSO and SOS induced by kinetics are related to the kinked oleic acid at the outer position in the SSO molecule and favorable end group structure for SOS. The fundamental understanding gained from such model systems can be used in many industrial formulations, particularly foods. 相似文献
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Mark R. Baker Laziz Bouzidi Nissim Garti Suresh S. Narine 《Journal of the American Oil Chemists' Society》2014,91(10):1685-1694
The phase composition of triacylglycerols (TAG) is determined by chemical structure and is greatly affected by kinetics. Positional isomerism and unsaturation are two key structural elements that govern, for a large part, the phase behavior of TAG during crystallization. Polymorphism, thermal properties, and microstructure of dioleoyl‐stearoyl isomers (OSO, SOO) were investigated at different cooling rates with XRD, DSC and PLM techniques, respectively. The physical properties of the symmetrical TAG were found to predictably vary with cooling rate; whereas, the properties of the asymmetrical TAG remained relatively constant. This was explained to be mainly due to the extra steric hindrance caused by asymmetry and the disturbances introduced at the “terrace” level via methyl‐end group interactions. The findings underscore the intricate contribution of saturation and symmetry to the phase trajectories of diunsaturated TAG. The knowledge gained will help understand the behavior of more complex materials and can be used for the manipulation of fat structures at different length scales and direct the manufacture of novel food systems and other relevant materials. 相似文献
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Farida Bouzidi Magali Fois Nacerddine Haddaoui 《Journal of Adhesion Science and Technology》2018,32(5):496-515
Poly(lactic acid) (PLA)/polypropylene (PP) blends composites were prepared by incorporating 3 wt.% of copper modified montmorillonite (MMT-Cu2+), obtained using cation exchange in a CuSO4 solution, and 10 wt.% of polypropylene-graft-maleic anhydride (PP-g-MA) as a compatibilizer then varying the PLA content until 50 wt.%. These materials were subjected to several investigations such as X-rays diffraction, dynamic mechanical thermal analysis (DMTA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and tensile and environmental tests. The DMTA analysis showed that the glassy PLA high stiffness and the PP crystalline phase compensate the decrease in the storage modulus occurring during the PP and PLA glass transitions, respectively. The variations of tan δ revealed no changes on the PP and PLA phases glass transitions temperatures which indicate the immiscibility of the two polymers, as supported by DSC analysis. Blends composites SEM micrographs stated the immiscibility of the system resulting in the poor adhesion of the PLA droplets to the PP matrix. Also, the blends composites exhibited intermediate tensile properties between those of PP and PLA. The incorporation of MMT-Cu2+ to the (50/50) PP/PLA blend accentuated its aptitude to water absorption and ensured an efficient antimicrobial activity over a satisfactorily long period of around six months. 相似文献