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The cases of 3 sibs presenting with isovaleric acidemia are reported. The first infant died when he was 9 day-old. The two others appear to have benefited from a controlled leucine diet which was introduced from the first days on of life. The clinical symptomatology, highly typical of the disease, is described. Diagnosis was not assessed on amino-acids chromatography but on the chromatography of volatile fatty acids. The mode of treatment is described: peritoneal dialysis, with the object of rounding a crucial cape, and overall controlled leucine diet, but supplemented by essential amino-acids.  相似文献   
85.
Integrated biodiesel processes based on reactive separations powered by solid acid/base catalysts are available nowadays, offering significant advantages such as minimal capital investment and operating costs, as well as no catalyst-related waste streams and no soap formation. However, the controllability of the process is just as important as the capital and operating savings. In such processes the small number of degrees of freedom is a drawback which makes it difficult to correctly set the ratio of reactant feeds and consequently to avoid impurities in the products. This work considers the process control of biodiesel production by reactive absorption, the main result being an efficient control structure that ensures the excess of methanol that is necessary for the total conversion of the fatty acids and for prevention of the difficult separations, while maintaining high purity of the water by-product. Rigorous simulations were performed - using Aspen Plus and Aspen Plus Dynamics as efficient computer-aided process engineering tools - for a plant producing 10 ktpy biodiesel from waste vegetable oil with high free fatty acids content, using solid acids as green catalysts. This reactive absorption process eliminates all conventional catalyst-related operations, and efficiently uses the raw materials and the reactor volume in an integrated setup that is well controllable in spite of the reduced number of degrees of freedom.  相似文献   
86.
Low-temperature electrical characteristics of n-type gate-all-around vertically-stacked silicon nanowire (SNW) field-effect transistors (FETs) with high-k/metal gate have been investigated and are compared to those with Fin and fully-depleted silicon-on-insulator (FD SOI) FETs. In particular, the effective electron mobilities behaviors are discussed. Nanowires with a rectangular cross section of 15 nm in width and 19 nm in height have shown a strongly degraded mobility as compared to those with Fin and FD SOI FETs. Low-temperature measurements have revealed that the mobility degradation is due to higher surface-roughness limited mobility. On the other hand, no significant difference in the interface trap densities among the kinds of FETs measured in the study have been observed from the temperature dependence in the subthreshold slope.  相似文献   
87.
We synthesized new macromonomers containing vinylsilane moiety by cationic ring-opening polymerization of 2-ethyl-2-oxazoline. Kinetic studies proved that initiation with vinylsilane derivative, bearing chloride counterion, is a fast process followed by a slow propagation and absence of termination. We used the dispersion polymerization of styrene as test for the stabilizing efficiency of the newly synthesized macromonomer. The dispersion polymerization tests allowed the investigation of the effect of the macromonomer concentration on the number average diameter of the prepared polystyrene microspheres and its polydispersity index. In addition, we compared the stabilizing efficiency of commercial poly(N-vinylpyrollidone) with that of our macromonomer. Copolymerization of styrene with 10 wt% oxazoline macromonomer yielded stable and monodisperse microspheres, having the number average diameter of 1.8 μm and a good size polydispersity index of 1.05.  相似文献   
88.
In this paper, an approach to control a 6-DoF stereo camera for the purpose of actively tracking the face of a human observer in the context of Human-Robot Interaction (HRI) is proposed. The main objective in the presented work is to cope with the critical time-delay introduced by the computer vision algorithms used to acquire the feedback variable within the control system. In the studied HRI architecture, the feedback variable is represented by the 3D position of a human subject. We proposed a predictive control method which is able to handle the high time-delay inserted by the vision elements into the control system of the stereo camera. Also, along with the predictive control approach, a novel 3D nose detection algorithm is suggested for the computation of the feedback variable. The performance of the implemented platform is given through experimental results.  相似文献   
89.
Liquid metals based on gallium have attracted considerable attention for soft and bioelectronics, thanks to their excellent combination of stretchability and conductivity. Nevertheless, owing to their large surface tension, these materials are notoriously difficult to pattern and shape into thin continuous films, or nanoscale 2D architectures, hindering practical use in systems with reduced dimensions. Herein, thanks to fine control in both substrate surface state and oxidation dynamics, a process for producing stretchable gallium-based conducting films with percolation down to 90 nm thickness is presented. By further combining this process with lithography, it is also demonstrated that the approach enables, for the first time, stable stretchable gallium-based optical metasurfaces with tunable resonance in the infrared. It is shown that oxygen partial pressure during evaporation determines the initial film percolation via an interplay between oxidation and dewetting. With this approach, conducting films with relative resistance change as low as 3% over 50% strain, with an excellent stability over 15k cycles are also demonstrated. Tunable soft optical metasurfaces with sub-micrometer feature sizes are also realized, paving the way toward a novel paradigm in soft electronics and photonics.  相似文献   
90.
Plasma treatment of contaminated water appears to be a promising alternative for the oxidation of aqueous organic pollutants. This study examines the kinetic and oxidation mechanisms of methyl tert-butyl ether (MTBE) in a dense medium plasma (DMP) reactor utilizing gas chromatography-mass spectrometry and gas chromatography-thermal conductivity techniques. A rate law is developed for the removal of MTBE from an aqueous solution in the DMP reactor. Rate constants are also derived for three reactor configurations and two pin array spin rates. The oxidation products from the treatment of MTBE-contaminated water in the DMP reactor were found to be predominately carbon dioxide, with smaller amounts of acetone, tert-butyl formate, and formaldehyde. The lack of stable intermediate products suggests that the MTBE is, to some extent, oxidized directly to carbon dioxide, making the DMP reactor a promising tool in the future remediation of water. Chemical and physical mechanisms together with carbon balances are used to describe the formation of the oxidation products and the important aspects of the plasma discharge.  相似文献   
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