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A sensitivity analysis of millimeter wave characteristics of siC IMPATT diodes

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Journal of semiconductors 2017年第6期38卷 58-65页

作者： s k swain J Pradhan G N Dash s R Pattanaik school of Physics sambalpur University Sambalpur Odisha 767019 India College of Engineering Bhubaneswar Bhubaneswar Odisha 751024 India National Institute of science and Technology Berhampur Odisha 761008 India

Ionization rate coefficients and saturation drift velocities for electrons and holes are the vital material parameters in determining the performance of an IMPATT *** have performed a sensitivity analysis of the millimeter wave characteristics of 4H-siC and 6H-siC IMPATT diodes with reference to the above mentioned material data and an operating frequency of 220 *** effect of a small variation in the ionization rate and drift velocity on the device characteristics like break down voltage,efficiency,noise measure and power output has been presented here.

关键词： IMPATT siC ionization rate saturation drift velocity, millimeter wave

Potentials of GaP as millimeter wave IMPATT diode with reference to si,GaAs and GaN

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红外与毫米波学报 2019年第4期38卷 395-402页

作者： Janmejaya Pradhan s k swain s R Pattnaik G N Dash College of Engineering Bhubaneswar Bhubaneswar Odisha 752024 India National Institute of science and Technology Berhampur Odisha 761008 India school of Physics Sambalpur University Sambalpur Odisha 768019 India

This paper presents the simulation results of DC,small-signal and noise properties of GaP based Double Drift Region( DDR) Impact Avalanche Transit Time( IMPATT) diodes. In simulation study we have considered the flat DDR structures of IMPATT diode based on GaP,GaAs,si and GaN( wurtzite,wz) material. The diodes are designed to operate at the millimeter window frequencies of 94 GHz and 220 GHz. The simulation results of these diodes reveal GaP is a promising material for IMPATT applications based on DDR structure with high break down voltage( V_B) as compared to si and GaAs IMPATTs. It is also encouraging to worth note GaP base IMPATT diode shows a better output power density of 4. 9 × 10~9 W/m^2 as compared to si and GaAs based IMPATT diode. But IMPATT diode based on GaN( wz) displays large values of break down voltage,efficiency and power density as compared to si,GaAs and GaP IMPATTs.

关键词： lmpact avalanche transit time(IMPATT) GaP GaN microwave and millimetre wave

POLY(METHYL METHACRYLATE)/sOY PROTEIN GREEN COMPOsITEs As GAs BARRIER MATERIALs

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Chinese Journal of Polymer science 2012年第3期30卷 397-404页

作者： sudhir k.kisku sarat k.swain Department of Chemistry North Orissa UniversityTakatpurBaripada-757003India Department of Chemistry Veer Surendra Sai University of TechnologyBurlaSambalpur-768018India

Poly（methyl methacrylate）/soy protein （PMMA/sP） composites were prepared by emulsion polymerization method using potassium persulphate （kPs） as the radical initiator. The interaction of soy protein with PMMA was evidenced by Fourier transformed infrared （FTIR） spectroscopy. The structure of PMMA/sP composite： was investigated by X-ray diffraction （XRD） study and scanning electron microscopy （sEM）. The thermal properties of soy protein and PMMA/sP composites were compared with soy protein and virgin PMMA sample. PMMA/sP composites were found to be flame retardant materials from the measurement of limiting oxygen index （LOI） of samples. The oxygen permeability of PMMA/sP composites was substantially decreased as compared to virgin PMMA.

关键词： soy protein Emulsion polymerization Biodegradability Oxygen permeability.

Nuclear structure and decay modes of Ra isotopes within an axially deformed relativistic mean field model

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Chinese Physics C 2018年第8期42卷 121-129页

作者： Rashmirekha swain s.k.Patra B.B.sahu school of Applied sciences KIIT Deemed to be UniversityBhubaneswar-751024OdishaIndia Institute of Physics Bhubaneswar-751005India

We examine the structural properties and half-life decay of Ra isotopes within the axially deformed Relativistic Mean-Field（RMF）theory with NL3 force *** work out the binding energy（BE）,RMs radii,two-neutron separation energies（s（2n））,and some other *** results are in good agreement with the finite-range droplet model（FRDM）and experimental *** the possibility of neutron magic number,theα-decay and cluster decay half-lives of Ra isotopes are calculated systematically using the Q-values obtained from the RMF *** decay half-life calculations are carried out by taking three different empirical *** calculated decay half-lives are found to be highly sensitive to the choice of *** shell or sub-shell closures are found at daughter nuclei with N=128 and N=126 when alpha and 8Be,12C,18O respectively are emitted from Ra *** the cluster radioactivity is affected by the shell closure of parent and daughter,a long half-life indicates the stability of the parent,and a small parent half-life indicates that the shell stability of the daughter against decay.

关键词： relativistic mean field nuclear bulk properties alpha and cluster decay half-life

Oxygen Barrier of Multiwalled Carbon Nanotube/Polymethyl Methacrylate Nanocomposites Prepared by in situ Method

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Journal of Materials science & Technology 2012年第5期28卷 391-395页

作者： Ajaya k. Pradhan sarat k. swain Department of Chemistry North Orissa University Takatpur Baripada 757003 India Department of Chemistry Veer Surendra Sai University of Technology Burla Sambalpur 768018 India

Multiwalled carbon nanotubes （MWCNTs）/poly（methyl methacrylate）（PMMA） nanocomposites were prepared by ultrasonic assisted emulsifier free emulsion polymerization technique with variable concentration of functionalized carbon nanotubes. MWCNTs were functionalized with H 2 sO 4 and HNO 3 with continuing sonication and polished by H 2 O 2 . The appearance of Fourier transform infrared absorption bands in the PMMA/MWCNT nanocomposites showed that the functionalized MWCNT interacted chemically with PMMA macromolecules. The surface morphology of functionalized MWCNT and PMMA/MWCNT nanocomposites were studied by scanning electron microscopy. The dispersion of MWCNT in PMMA matrix was evidenced by high resolution transmission electron microscopy. The oxygen permeability of PMMA/MWCNT nanocomposites gradually decreased with increasing MWCNT concentrations.

关键词： Nanocomposites Morphology Permeability Dispersion

Information Entropy and squeezing of Quantum Fluctuations in a Two-Level Atom

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Chinese Physics Letters 2000年第11期17卷 798-800页

作者： FANG Mao-Fa ZHOU Peng s.swain Department of Physics Hunan Normal UniversityChangsha 410081 Anhui Institute of Optics and Fine Mechanics Chinese Academy of Sciences Hefei 230031 Department of Applied Mathematics and Theoretical Physics The Queens University of BelfastBelfast BT7 INNUK

We study the atomic squeezing in the language of the quantum information theory.A rigorous entropy uncertainty relation which suits for characterizing the squeezing of a two-level atoms is obtained,and a general definition of information entropy squeezing in the two-level atoms is *** information entropy squeezing of two-level atoms interacting with a single-mode quantum field is *** results show that the information entropy is a superior measure of the quantum uncertainty of atomic observable,also is a remarkable good precision measure of atomic *** the population difference of two-level atom is zero,the definition of atomic squeezing based on the Heisenberg uncertainty relation is trivial,while the definition of information entropy squeezing of the atom based on the entropy uncertainty relation is valid and can provide full information on the atomic squeezing in any cases.

关键词： theory entropy quantum

Quantum Entropic Dynamics of a Trapped Ion in a standing Wave

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Chinese Physics Letters 2000年第12期17卷 885-887页

作者： FANG Mao-Fa ZHOU Peng s.swain Department of Physics Hunan Normal UniversityChangsha410081 Anhui Institute of Optics and Fine Mechanics Chinese Academy of SciencesHefei 230031 Department of Applied Mathematics and Theoretical Physics The Queens University of BelfastBelfast BT7 lNNUK

By performing a unitary transformation,we transform the Hamiltonian of the trapped ion in any position of standing wave to that of the normal Jaynes-Cummings model in ionic bare basis and we obtain a general evolution operator of the trapped ion *** study the quantum entropic dynamics of the phonons and trapped *** results show that,when the trapped ion is located at the node of standing wave,the quantum entropic dynamics of phonons and trapped ion are the same as the one of the field in the Jaynes-Cummings *** the trapped ion deviates from the node of standing wave,the entropies of the phonons and ion keep their maximum value except at the initial stage,and the phonons and trapped ion become extremely entangled.

关键词： Quantum trapped standing

Effects of Boron Nitride Nanopowder on Thermal, Chemical and Gas Barrier Properties of starch

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Chinese Journal of Polymer science 2014年第10期32卷 1311-1318页

作者： Gopal C. Pradhan Lingaraj Behera sarat k. swain Department of chemistry North Orissa University Takatpur Baripada 757003 India Department of Chemistry Veer Surendra Sai University of Technology Burla Sambalpur 768018 India

starch/boron nitride （starch/BN） bionanocomposites were prepared with the reinforcement of boron nitride nano powder by solution technique. The dispersion of BN in the starch was achieved by a continuous sonication process. The interaction between starch and boron nitride nanopowder was investigated by Fourier transform infrared （FTIR） spectroscopy. The structural properties of starch/BN bionanocomposites was studied by X-ray diffraction （XRD）. The high resolution transmission electron microscopy （HRTEM） was used for the study of dispersion of boron nitride in starch matrix and diffraction patterns were studied by selected area electron diffraction （sAED）. Thermal stability of the starch was increased with rising concentrations of boron nitride due to incorporation of rigid nano BN with starch matrix. The substantial reduction in oxygen permeability was obtained by increasing the concentration of BN. The biodegradability of synthesized bionanocomposites was measured by using activated sludge water. Further, it was noticed that, starch/BN bionanocomposites are resistant towards inorganic acids and bases. The tensile strength of starch/BN bionanocomposites was increased whereas; the water resistance property of the materials was decreased with increasing BN loading.

关键词： starch Boron nitride Bionanocomposites Oxygen permeability.

The future of wireless capsule endoscopy

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World Journal of Gastroenterology 2008年第26期14卷 4142-4145页

作者： Paul swain Department of surgical Oncology and Technology London University (Imperial College)London NW3 1TNUnited Kingdom

We outline probable and possible developments with wireless capsule endoscopy. It seems likely that capsule endoscopy will become increasingly effective in diagnostic gastrointestinal endoscopy. This will be attractive to patients especially for cancer or varices detection because capsule endoscopy is painless and is likely to have a higher take up rate compared to conventional colonoscopy and gastroscopy. Double imager capsules with increased frame rates have been used to image the esophagus for Barrett's and esophageal varices. The image quality is not bad but needs to be improved if it is to become a realistic substitute for flexible upper and lower gastrointestinal endoscopy. An increase in the frame rate, angle of view, depth of field, image numbers, duration of the procedure and improvements in illumination seem likely. Colonic, esophageal and gastric capsules will improve in quality, eroding the supremacy of flexible endoscopy, and become embedded into screening programs. Therapeutic capsules will emerge with brushing, cytology, fluid aspiration, biopsy and drug delivery capabilities. Electrocautery may also become possible. Diagnostic capsules will integrate physiological measurements with imaging and optical biopsy, and immunologic cancer recognition. Remote control movement will improve with the use of magnets and/or electrostimulation and perhaps electromechanical methods. External wireless commands will influence capsule diagnosis and therapy and will increasingly entail the use of real-time imaging. However, it should be noted that speculations about the future of technology in any detail are almost always wrong.

关键词： Wireless Capsule Endoscopy Future Complementary oxide silicone Charge coupled device Therapy screening Colonoscopy Biopsy Cancer Electrocautery