Current Issue : April - June Volume : 2012 Issue Number : 2 Articles : 7 Articles
A complete design flow starting from the technological process development up to the fabrication of digital circuits is presented.\r\nThe aim of this work is to demonstrate the GaAs Enhancement/Depletion (E/D) double stop-etch technology implementation\r\nfeasibility for digital applications, aimed at mixed signal circuit integration. On the basis of the characterization of small E/D\r\ndevices with different Gate peripheries, developed by the SELEX-SI foundry, and the analysis of several GaAs-based logical families,\r\nthe most suitable logic for the available technology has been selected. Then, simple test vehicles (level shifters, NOR logic gates and\r\nD Flip-Flops) have been designed, realized, and measured to validate the design strategy applied to the GaAs E/D process. These\r\nlogical circuits are preliminary to the design of a more complex serial-to-parallel converter, to be implemented onto the same chip\r\ntogether with RF analog blocks, such as stepped attenuators and phase shifters....
In this study a one step method for the preparation of substituted anilides of\r\nquinoline-2-carboxylic acid was developed. This efficient innovative approach is based on\r\nthe direct reaction of an acid or ester with substituted anilines using microwave irradiation.\r\nThe optimized method was used for the synthesis of a series of eighteen substituted\r\nquinoline-2-carboxanilides. The molecular structure of N-(4-bromophenyl)quinoline-2-\r\ncarboxamide as a model compound was determined by single-crystal X-ray diffraction.\r\nIt crystallizes in the monoclinic space group with four molecules within the unit cell and\r\nthe total structure of the compound can be described as ââ?¬Å?a slightly screwed boatââ?¬Â....
This paper presents the formation of the parasitic components that exist in the RF MOSFET structure during its high-frequency\r\noperation. The parasitic components are extracted from the transistor�s S-parameter measurement, and its geometry dependence\r\nis studied with respect to its layout structure. Physical geometry equations are proposed to represent these parasitic components,\r\nand by implementing them into the RF model, a scalable RFCMOS model, that is, valid up to 49.85 GHz is demonstrated. A new\r\nverification technique is proposed to verify the quality of the developed scalable RFCMOS model. The proposed technique can\r\nshorten the verification time of the scalable RFCMOS model and ensure that the coded scalable model file is error-free and thus\r\nmore reliable to use....
HDA-capped ZnO nanoparticles were prepared by solvothermal method using solvents of different polarities. A number of\nparameters were kept constant such as temperature, pressure, time, and pH while solvents were varied, that is, water, ethanol,\nand acetone. The TEM was used for the structural properties and morphologies such as spheres, mixture of rods, and spheres and\nstars were obtained in ethanol, acetone, and water, respectively, in a given reaction time of 15 minutes. Both ethanol and acetone\ngave rods with high aspect ratio primarily because of the lengths of the rods. Water and ethanol have the hydroxyl groups which\ninteract with nanoparticles from nucleation, growth, and termination giving rise to nonspherical shapes. The hydroxyl group\npromotes growth in a nonuniform way resulting in stars and rods. The optical features were typical of ZnO nanoparticles with\nexcitonic peaks in the range 368 to 374nm from their absorption spectra. The XRD patterns of the particles gave the most stable\nform of ZnO which is the hexagonal phase, with high degree of crystallinity and with the 101 plane predominant in all solvents....
Background: Limb-salvage surgery has been well recognized as a standard treatment and alternative to amputation for\r\npatients with malignant bone tumors. Various limb-sparing techniques have been developed including tumor prosthesis,\r\nallograft, autograft and graft-prosthesis composite. However, each of these methods has short- and long-term\r\ndisadvantages such as nonunion, mechanical failures and poor limb function. The technique of intracorporeal devitalization\r\nof tumor-bearing bone segment in situ by microwave-induced hyperthermia after separating it from surrounding normal\r\ntissues with a safe margin is a promising limb-salvage method, which may avoid some shortcomings encountered by the\r\nabove-mentioned conventional techniques. The purpose of this study is to assess the healing process and revitalization\r\npotential of the devitalized bone segment by this method in a dog model. In addition, the immediate effect of microwave\r\non the biomechanical properties of bone tissue was also explored in an in vitro experiment.\r\nMethods: We applied the microwave-induced hyperthermia to devitalize the distal femurs of dogs in situ. Using a\r\nmonopole microwave antenna, we could produce a necrotic bone of nearly 20 mm in length in distal femur. Radiography,\r\nbone scintigraphy, microangiography, histology and functional evaluation were performed at 2 weeks and 1, 2, 3, 6, 9 and\r\n12 months postoperatively to assess the healing process. In a biomechanical study, two kinds of bone specimens, 3 and\r\n6 cm in length, were used for compression and three-point bending test respectively immediately after extracorporeally\r\ndevitalized by microwave.\r\nFindings: An in vivo study showed that intracorporeally and in situ devitalized bone segment by microwave had great\r\nrevitalization potential. An in vitro study revealed that the initial mechanical strength of the extracorporeally devitalized\r\nbone specimen may not be affected by microwave.\r\nConclusion: Our results suggest that the intracorporeal microwave devitalization of tumor-bearing bone segment in situ\r\nmay be a promising limb-salvage method....
We present the results of the measurement of complex dielectric permittivity, in the microwave frequency region, on glass\nreinforced polybutylene terephthalate (PBT) with blue inorganic pigments. The cavity resonant method had been used in order\nto measure the shift in the resonant frequency of the cavity, caused by the insertion of a sample, which can be related to the real\npart of the complex permittivity. Also, the quality factor of the cavity decreases with the insertion of a sample. The changes in the\ninverse of this quality factor give the imaginary part. In order to predict the dielectric behavior of this composite, we had developed\na program of numerical simulation to calculate the complex permittivity of the inclusion. By using some of dielectric mixture laws\n(Maxwell-Wagner-Sillars, Hanai, Looyenga, inverse and direct Wiener, and Bruggemann), we can predict the dielectric behavior\nof the composite in a large range of volume fraction of inclusions....
A female patient, 36-years-old, complained of bilateral palatal pain on the anatomical area of upper\r\nsecond molars. The painful condition of palatal mucosa erosion was observed. Palatal erosions or\r\nulcerations may be caused by heated food cooked in microwave ovens. We present a case of a\r\nbilateral palatal burn caused by cheese-pie. Concluding, any food containing cheese, when heated\r\nin microwave oven, may cause palatal burn if eaten immediately....
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