A 30 A 30 V DMOS motor controller and driver

A power DMOS half bridge (R_on=40 mΩ, 30-V operating voltage, 30 A peak current) for windshield-wiper motors is presented. Double speed (DC and 20 kHz PWM output), motor braking, full protection and fault detection functions, and timing sequence (up to 200 ms) are performed by an integrated circuit that integrates the pull-up power transistor as well as the signal circuits on a technology process that allows the integration of bipolar, CMOS, and power DMOS transistors. The power pull-down transistor is a discrete device mounted in the same power package (Multi-watt 11) on an isolated tab     

Developmental regulation of the Drosophila Tropomyosin I (TmI) gene is controlled by a muscle activator enhancer region that contains multiple cis-elements and binding sites for multiple proteins

We have analyzed in Paramecium cells the occurrence and intracellular distribution of the high capacity/low affinity calcium-binding proteins, calsequestrin (CS) and calreticulin (CR) using antibodies against CS from rat skeletal muscle and against CR from rat liver, respectively. As revealed by Western blots, a CS-like protein isolated by affinity chromatography from Paramecium cells comigrated with CS isolated from rat skeletal muscle. The immunoreactivity of this 53 kDa protein band was blocked when the antibodies had been preadsorbed with purified rat CS. A band of identical molecular size was shown to bind 45Ca in overlays. By immunofluorescence and immunogold labeling this CS-like protein was localized selectively to the extended subplasmalemmal calcium stores, the "alveolar sacs", which cover almost the entire cell surface. Concomitantly the 53 kDa 45Ca-binding band became increasingly intense in overlays as we increasingly enriched alveolar sacs. Antibodies against rat CR react with a 61 kDa band but do not cross-react with CS-like protein in Paramecium. These antibodies selectively stained intracellular reticular structures, identified bona fide as endoplasmic reticulum.     

A High-Order Local Projection Stabilization Method for Natural Convection Problems

In this paper, we propose a local projection stabilization (LPS) finite element method applied to numerically solve natural convection problems. This method replaces the projection-stabilized structure of standard LPS methods by an interpolation-stabilized structure, which only acts on the high frequencies components of the flow. This approach gives rise to a method which may be cast in the variational multi-scale framework, and constitutes a low-cost, accurate solver (of optimal error order) for incompressible flows, despite being only weakly consistent. Numerical simulations and results for the buoyancy-driven airflow in a square cavity with differentially heated side walls at high Rayleigh numbers (up to \(Ra=10^7\)) are given and compared with benchmark solutions. Good accuracy is obtained with relatively coarse grids.     

A Review of Variational Multiscale Methods for the Simulation of Turbulent Incompressible Flows

Various realizations of variational multiscale (VMS) methods for simulating turbulent incompressible flows have been proposed in the past fifteen years. All of these realizations obey the basic principles of VMS methods: they are based on the variational formulation of the incompressible Navier–Stokes equations and the scale separation is defined by projections. However, apart from these common basic features, the various VMS methods look quite different. In this review, the derivation of the different VMS methods is presented in some detail and their relation among each other and also to other discretizations is discussed. Another emphasis consists in giving an overview about known results from the numerical analysis of the VMS methods. A few results are presented in detail to highlight the used mathematical tools. Furthermore, the literature presenting numerical studies with the VMS methods is surveyed and the obtained results are summarized.     

公共的私人空间 意大利Giovannoni公寓及工作室

意大利著名设计师Stefano Giovannoni不久前将一个旧工厂的厂房改建成居家与办公相结合的空间。项目的地点在米兰ViaTortona区附近。改建完成之后，由于其在建筑与室内设计上的特殊性，这个房子几乎成了展览及各类活动的举办地，尤其是salone国际设计周期间，这里更是热闹非凡。     

Processing of β-Silicon Nitride from Water-Based alpha-Silicon Nitride, Alumina, and Yttria Powder Suspensions

A water-based route for processing ß-Si₃N₄ from alpha-Si₃N₄, Al₂O₃, and Y₂O₃ powder mixtures was established. The surface charges and isoelectric points of the three different powders were investigated within the pH range from pH 3 to pH 12. Citric acid diammonium salt was found to be an effective deflocculant for shifting the isoelectric points to pH 3.5 for Al₂O₃ and to pH 6 for Y₂O₃. Aluminum hydroxide (Al(OH)₃) showed strong interaction with the Si₃N₄ powder, shifting the isoelectric point from pH 7 to pH 5.5. Low-viscosity, high-solids-loading suspensions (60-63 vol%) thus were possible at pH 9.7. The preparation of homogeneous and stable suspensions with a solids content of ≤61 vol% and a viscosity <1 Pa·s was limited to a pH regime between pH 9 and pH 10.5 because of the high solubility of yttria. The homogeneous suspensions were easily solidified by direct coagulation casting (DCC), using the urease-catalyzed decomposition of urea at pH 9 to pH 10, by forming salt. No shrinkage cracking, sedimentation, or phase separation was observed during coagulation or drying. The green-density distribution was homogeneous throughout all bodies, even for complex geometries.     

MALDI‐TOF‐CID for the microstructure elucidation of polymeric hydrolysable tannins

High molar mass wood tannin extracts are complex mixtures that are distributed in both molar mass and chemical composition. Hydrolysable tannins from tara, Turkey gall, and chestnut woods were analyzed and compared using matrix‐assisted laser desorption/ionization time‐of‐flight (MALDI‐TOF) mass spectrometry. Although MALDI‐TOF MS reveals the oligomer structure of the tannins, this method cannot distinguish between isomers with isobaric masses and, therefore, ambiguous structural assignments were made in a number of cases. To determine the actual microstructures present, MALDI‐TOF‐CID (collision induced dissociation) experiments were conducted. MALDI‐TOF‐CID enables monomer sequence determination and positive assignments of isobaric structures can be made. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Functionalized lactic acid macromonomers via polycondensation as an alternative to ring opening polymerization

Engineered polylactic acid (PLA) nanoparticles synthesized from oligo(lactic acid) macromonomers have been studied over the last decades for controlled drug delivery. These macromonomers are typically produced via ring-opening polymerization (ROP) of the cyclic dimer lactide, initiated by 2-hydroxyethyl methacrylate (HEMA). This reaction route, despite leading to well-defined macromonomers, relies on the production of lactide from lactic acid, which burdens the ROP overall cost for more than 30%. In this work, we report the synthesis of PLA-based macromonomers by direct polycondensation of lactic acid in the presence of HEMA as a valuable alternative to ROP. In particular, we compare the two processes side by side, focusing on the production of three HEMA-LA_n macromonomers, with n = 2, 4, and 6. Detailed kinetic models are developed for both reaction systems, and the corresponding parameters are estimated by fitting the experimental data. Through these models, the reaction kinetics as well as the time evolution of the entire chain length distributions of the products from polycondensation and ROP could be reliably predicted. This way, we demonstrated that polycondensation is a valuable alternative to ROP only for macromonomers with an average chain length of up to 4 and that ROP remains the main route to longer chains, when a strict control over the chain length distribution is required.     

Synthesis,spectral, crystal structures,Hirshfeld surface analysis and DFT studies on bis(N,N-di(4-methoxybenzyl)dithiocarbamato-S,S′)zinc(II) and its imine adducts: new precursor for the preparation of hexagonal ZnS

[Zn(4-mbzdtc)₂] (1), [Zn(4-mbzdtc)₂(py)] (2), [Zn₂(4-mbzdtc)₄(4,4′-bipy)] (3), and [Zn(4-mbzdtc)₂(2,2′-bipy)] (4), (where, 4-mbzdtc?=?N,N-di(4-methoxybenzyl)dithiocarbamate) were prepared and characterized by elemental analysis, infrared, ¹H and ¹³C NMR spectroscopy and the structures of 1 and 3 were elucidated by X-ray crystallography. The monomeric structure of 1 shows a distorted tetrahedral geometry for zinc(II). The coordination geometry around zinc in dinuclear complex 3 is an intermediate between square pyramidal and trigonal bipyramidal. The downfield shift of NCS₂ carbon signal for imine adducts of 2–4 compared to those found in parent complex 1 is attributed to the change in coordination number and steric effect exerted by the nitrogen donor ligand. Hirshfeld surface analysis was used to visualize intermolecular interactions in the crystal structure of 1 and 3. The geometry optimization of 1 is performed using DFT with the B3LYP-LANL2DZ basis set. Solvothermal decomposition of 1 yielded only hexagonal zinc sulfide nanoparticles. Zinc sulfide nanoparticles were characterized using powder X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectra and diffuse reflectance spectra. DRS study of ZnS nanoparticles shows the quantum confinement effect with a band gap of 3.74?eV.