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1.
Ferrite particles coated with biocompatible phases can be used for hyperthermia treatment of cancer. We have synthesized substituted
calcium hexaferrite, which is not stable on its own but is stabilized with small substitution of La. Hexaferrite of chemical
composition (CaO)0.75(La203)0.20(Fe2O3)6 was prepared using citrate gel method. Hydroxyapatite was prepared by precipitating it from aqueous solution of Ca(NO3)2 and (NH4)2HPO4 maintaining pH above 11. Four different methods were used for coating of hydroxyapatite on ferrite particles. SEM with EDX
and X-ray diffraction analysis shows clear evidence of coating of hydroxyapatite on ferrite particles. These coated ferrite
particles exhibited coercive field up to 2 kOe, which could be made useful for hysteresis heating in hyperthermia. Studies
by culturing BHK-21 cells and WBC over the samples show evidence of biocompatibility. SEM micrographs and cell counts give
clear indication of cell growth on the surface of the sample. Finally coated ferrite particle was implanted in Kasaulli mouse
to test its biocompatibility. The magnetic properties and biocompatibility studies show that these hydroxyapatite coated ferrites
could be useful for hyperthermia. 相似文献
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Dasgupta U. Wooi Gan Yeoh Chun Geik Tan Sheng Jau Wong Mori H. Singh R. Itoh M. 《Microwave Theory and Techniques》2002,50(11):2443-2452
An implementation of the IF section of WCDMA mobile transceivers with a set of two chips fabricated in an inexpensive 0.35-/spl mu/m two-poly three-metal CMOS process is presented. The transmit/receive chip set integrates quadrature modulators and demodulators, wide dynamic range automatic gain control (AGC) amplifiers, with linear-in-decibel gain control, and associated circuitry. This paper describes the problems encountered and the solutions envisaged to meet stringent specifications, with process and temperature variations, thus overcoming the limitations of CMOS devices, while operating at frequencies in the range of 100 MHz-1 GHz. Detailed measurement results corroborating successful application of the new techniques are reported. A receive AGC dynamic range of 73 dB with linearity error of less than /spl plusmn/2 dB and spread of less than 5 dB for a temperature range of -30/spl deg/C to +85/spl deg/C in the gain control characteristic has been measured. The modulator measurement shows a carrier suppression of 35 dB and sideband/third harmonic suppression of over 46 dB. The core die area of each chip is 1.5 mm/sup 2/. 相似文献
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Two techniques for designing function-dependent easily testable programmable logic arrays are presented. The techniques can detect all the multiple stuck-at, crosspoint and bridging faults, as compared with most of the existing techniques where some of the faults, especially bridging faults, remain undetected.<> 相似文献
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VIMTEX: A Visualization Interface for Multivariate,Time‐Varying,Geological Data Exploration 下载免费PDF全文
Observing interactions among chemical species and microorganisms in the earth's sub‐surface is a common task in the field of geology. Bioremediation experiments constitute one such class of interactions which focus on getting rid of pollutants through processes such as carbon sequestration. The main goal of scientists’ observations is to analyze the dynamics of the chemical reactions and understand how they collectively affect the carbon content of the soil. In our work, we extract the high‐level goals of geologists and propose a visual analytics solution which helps scientists in deriving insights about multivariate, temporal behavior of these chemical species. Specifically, our key contributions are the following: i) characterization of the domain‐specific goals and their translation to exploratory data analysis tasks, ii) developing an analytical abstraction in the form of perceptually motivated screen‐space metrics for bridging the gap between the tasks and the visualization, and iii) realization of the tasks and metrics in the form of VIMTEX, which is a set of coordinated multiple views for letting scientists observe multivariate, temporal relationships in the data. We provide several examples and case studies along with expert feedback for demonstrating the efficacy of our solution. 相似文献
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The effect of nonlinear signal absorption (NLSA) due to ground-state absorption and excited-state absorption in a transversely pumped high-power dye laser amplifier is theoretically examined with a one-dimensional steady-state model for a dye amplifier pumped by a copper vapor laser. A well-approximated analytical expression for the extraction efficiency is derived, from which the effect of NLSA in reducing the amplifier efficiency can be appreciated immediately and can also be interpreted in terms of certain characteristic lengths. The reduction in efficiency due to NLSA is found to be largely independent of the pump power, provided that the signal power is increased linearly with the pump power to continue to saturate the amplifier gain and suppress amplified spontaneous emission. 相似文献
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Kunal Sain Abhishek Dasgupta Utpal Garain 《International Journal on Document Analysis and Recognition》2011,14(1):75-85
Performance evaluation of mathematical expression recognition systems is attempted. The proposed method assumes expressions
(input as well as recognition output) are coded following MathML or TEX/LaTEX (which also gets converted into MathML) format. Since any MathML representation follows a tree structure, evaluation of
performance has been modeled as a tree-matching problem. The tree corresponding to the expression generated by the recognizer
is compared with the groundtruthed one by comparing the corresponding Euler strings. The changes required to convert the tree
corresponding to the expression generated by the recognizer into the groundtruthed one are noted. The number of changes required
to make such a conversion is basically the distance between the trees. This distance gives the performance measure for the
system under testing. The proposed algorithm also pinpoints the positions of the changes in the output MathML file. Testing
of the proposed evaluation method considers a set of example groundtruthed expressions and their corresponding recognized
results produced by an expression recognition system. 相似文献