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Chinese Journal of Chemistry 2005年第9期23卷 1157-1164页

作者： PANdey, Jata Dhari HArOON, SHahla CHHABrA, Jyotsna dey, ranjan MISrA, Krishna Department of Chemistry University of Allahabad Allahabad 211-002 India

Experimental determination of density, ultrasonic velocity and viscosity of two pyrimidine bases thymine and cytosine along with their respective nucleosides, thymidine and cytidine has been carried out in aqueous urea solutions in the presence of different concentrations of three salts, viz. NaC1, KCl and CaCl2. The experimental data have been used for the computation of various thermodynamic parameters, viz. apparent molar volume, apparent molar compressibility, coefficients A and B of the Jones-Dole equation, internal pressure, acoustic impedance, etc. Structural studies of solutions under investigation have also been carried out by ultraviolet spectroscopy, and an at- tempt has been made to collaborate the findings of ultraviolet spectroscopy with results obtained thermodynami- cally.

关键词： interaction bivalent ion thermodynamic property ultraviolet spectroscopy ionic size

Numerical Visualization of Air Intake Induced by Free Surface Vortex

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Journal of Thermal Science 2017年第6期26卷 540-544页

作者： Young Kyu Park Mohan Kumar dey Yoon Hwan Choi Yeon Won Lee research Institute of Industrial Science & Technology Pukyong National University Busan Korea Interdisciplinary Program of Biomedical Mechanical and Electrical Engineering Pukyong National University Busan Korea Department of Mechanical Design Engineering Pukyong National University Busan Korea

Free surface vortex control is vital in a pump sump system because the air absorbed by free surface vortex induc- es noise, vibration, and cavitation corrosion on the pumping system. In this study, the change of free surface vor- tex and air absorption in a pump intake has been investigated by the Volume of Fraction （VOF） method with steady multiphase flow model in order to represent the behavior of the free surface vortex exactly. The homoge- neous free surface model is used to apply interactions of air and water. The results show that air intake by the free surface vortex motion can be visualized using the iso-surface of air volume fraction. The vortices make an air column from the free surface to the pump intake. Also, it was found that the flee surface vortex can be controlled by installing curtain walls.

关键词： free surface vortex numerical visualization curtain wall air intake

Phenomenological modelling of flow behaviour of 20MnMoNi55 reactor pressure vessel steel at cryogenic temperature with different strain rates

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Defence Technology（防务技术） 2019年第3期15卷 326-337页

作者： Swagatam Paul Partha dey Snehasish Bhattacharjee Sanjib Kumar Acharyya Prasanta Sahoo Jayanta Chattopadhyay Department of Mechanical Engineering Jadavpur University Kolkata India Department of Mechanical Engineering Academy of Technology Hooghly West Bengal India Bhaba Atomic research Centre Mumbai India

In the present study a phenomenological constitutive model is developed to describe the flow behaviour of 20MnMoNi55 low carbon reactor pressure vessel (rPV) steel at sub-zero temperature under different strain rates. A set of uniaxial tensile tests is done with the variation of strain rates and temperature ranging from 10^-4s^-1 to 10^-1s^-1 and -80℃ to 140℃ respectively. From the experimental data, family of flow curves at different temperatures and strain rates are generated and fitted exponentially. The strain rate and temperature dependence of the coefficients of the exponential flow curves are extracted from these curves and characterised through a general phenomenological constitutive coupled equation. The coefficients of this coupled equation are optimised using genetic algorithm. Finite element simulation of tensile tests at different strain rates and temperatures are done using this coupled equation in material model of Abaqus FEA software and validated with experimental results. The novelties of proposed model are:(a) it can predict precisely the flow behaviour of tensile tests (b) it is a simple form of equation where fitting parameters are both function of strain rate ratio and temperature ratio,(c) it has ability to characterize flow behaviour with decreasing subzero temperatures and increasing strain rates.

关键词： Flow behaviour rPV steel Cryogenic temperature Strain rate

Mechanical properties and microstructural evolution of ultrafine grained zircaloy-4 processed through multiaxial forging at cryogenic temperature

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Transactions of Nonferrous Metals Society of China 2015年第7期25卷 2221-2229页

作者： D.FULOrIA S.gOEL r.JAYAgANTHAN D.SrIVASTAVA g.K.dey N.SAIBABA Department of Metallurgical and Materials Engineering Centre of Nanotechnology ⅡT Roorkee Materials Science Division Bhabha Atomic Research Center Nuclear Fuel Complex Limited

The mechanical properties and microstructural evolution of zircaloy-4 subjected to cumulative strains of 1.48,2.96,4.44 and 5.91 through multiaxial forging（MAF） at cryogenic temperature（77 K） were *** mechanical properties of the MAF treated alloy were measured through universal tensile testing and Vickers hardness testing *** zircaloy-4 deformed up to a cumulative strain of 5.91 showed improvement in both ultimate tensile strength and hardness from 474 MPa to 717 MPa and from HV 190 to HV 238,respectively,as compared with the as-received ***,there was a noticeable decrement in ductility（from 18%to 3.5%） due to the low strain hardening ability of deformed *** improvement in strength and hardness of the deformed alloy is attributed to the grain size effect and higher dislocation density generated during multiaxial *** microstructural evolutions of deformed samples were characterized by optical microscopy and transmission electron microscopy（TEM）.The evolved microstructure at a cumulative strain of 5.91 obtained after MAF up to 12 cycles depicted the formation of ultrafine grains with an average size of 150-250 nm.

关键词： zircaloy-4 multiaxial forging cryogenic temperature ultrafine-grain microstructural evolution mechanical properties

Substance use disorders among older adults: A review of randomized controlled pharmacotherapy trials

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World Journal of Psychiatry 2019年第5期9卷 78-82页

作者： rajesh r Tampi Aarti Chhatlani Hajra Ahmad Kripa Balaram Joel dey ricardo Escobar Thejasvi Lingamchetty Department of Psychiatry and Behavioral Sciences Cleveland Clinic Akron GeneralOhioNH 44106United States Cleveland Clinic Lerner College of Medicine of Case Western reserve University ClevelandOH 44109United States Savant Care Clinic CaliforniaCA 90277United States Department of Psychiatry MetroHealthClevelandOH 44109United States Case Western reserve University School of Medicine ClevelandOH 44109United States

Substance use disorders(SUDs)are a growing problem among older ***,disulfiram,and naltrexone are United States Food and Drug Administration(referred to as FDA)approved for the treatment of alcohol use disorder,and buprenorphine is approved for the treatment of opiate use disorder among ***,the data on the use of these medications for the treatment of SUDs among older adults are unclear from randomized controlled trials(referred to as rCTs).A review of the literature indicates that there are only two rCTs that evaluated the use of pharmacologic agents for SUDs among older adults(≥50 years).One trial evaluated the use of naltrexone when compared to placebo for the treatment of alcohol use disorder among individuals,50-70 years in *** other trial evaluated the use of naltrexone or placebo as adjuncts with sertraline in the treatment of alcohol use disorder among individuals older than 55 years in *** trials indicated that the use of naltrexone reduced the rates of relapse among older adults with alcohol use ***,we did not identify any rCTs that studied the use of buprenorphine,acamprosate,or disulfiram for SUDs among older *** on available evidence,it would be safe to conclude that limited data indicate some efficacy for naltrexone in the treatment of alcohol use disorder among older ***,data from controlled trials on the use of other medications that are FDA approved for the treatment of SUDs among younger adults are nonexistent among older adults with SUDs.

关键词： Older adults Substance use Naltrexone Acamprosate Disulfiram Buprenorphine

Voltage-controlled NiO/ZnO p–n heterojunction diode: a new approach towards selective VOC sensing

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Microsystems & Nanoengineering 2020年第1期6卷 894-902页

作者： Sayan dey Swati Nag Sumita Santra Samit Kumar ray Prasanta Kumar guha Department of Electronics&Electrical Communication Engineering Indian Institute of TechnologyKharagpur 721302India Department of Electrical Engineering National Institute of TechnologyAgartala 99046India Department of Physics Indian Institute of TechnologyKharagpur 721302India Department of Physics Belda CollegeBelda 721424India S N Bose National Centre for Basic Sciences Kolkata 700106India

Metal oxide resistive gas sensors suffer from poor selectivity that restricts their practical *** sensor arrays are used to improve selectivity which increased the system ***,we have proposed a novel NiO/ZnO-based p–n junction single-diode device for selective sensing of several volatile organic compounds(VOCs)simultaneously by tuning bias *** operating voltage was varied between 3 and 5 volts to achieve selective sensing of 2-propanol(19.1 times for 95ppm with response and recovery times of 70 s and 55s respectively‚at 3 volts),toluene(20.1 times for 95 ppm with response and recovery times of 100 s and 60 s respectively,at 4 volts),and formaldehyde(11.2 times for 95 ppm with response and recovery times of 88 s and 54s respectively,at 5 volts).A probable mechanism of the tunable selectivity with operating bias voltage due to increase in surface carriers with increasing voltage was hence put ***,this device may play an important role to develop future selective multiple VOC sensor thereby replacing standard sensor arrays.

关键词： selectivity hence thereby

Software radio: A review of Design Considerations and Digital Hardware Choices

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China Communications 2009年第1期6卷 64-72页

作者： Parul gupta Pradipta dey Shivkumar Kalyanaraman Wang Qing Chen Jianwen Lin YongHua IBM India research Lab Bangalore IBM India research Lab Delhi IBM China research Lab Beijing

This paper reviews the requirements for Software Defi ned radio (SDr) systems for high-speed wireless applications and compares how well the different technology choices available-from ASICs, FPgAs to digital signal p... 详细信息

关键词： ASIC FPgA DSP gPP processor software radio SDr wireless networks

A multi-attribute decision making approach of mix design based on experimental soil characterization

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Frontiers of Structural and Civil Engineering 2018年第3期12卷 361-371页

作者： Amit K. BErA Tanmoy MUKHOPADHYAY Ponnada J.MOHAN Tushar K. dey Faculty of Science & Technology The ICFAI University Dehradun India College of Engineering Swansea University Swansea UK Department of Civil Engineering National Institute of Technical Teachers' Training and Research (NIT'ITR) Kolkata India

The clay mineral composition is one of the major factors that governs the physical properties of silty sand subgrade. Therefore, a thorough knowledge of mineral composition is essential to predict the optimum engineering properties of the soil, which is generally characterized by different indices like maximum dry density （MDD）, California bearing ratio （CBr）, unconfined compressive strength （UCS） and free swelling index （FSI）. In this article, a novel multi- attribute decision making （MADM） based approach of mix design has been proposed for silty sand- artificial clay mix to improve the characteristic strength of a soil subgrade. Experimental investigation has been carried out in this study to illustrate the proposed approach of selecting appropriate proportion for the soil mix to optimize all the above mentioned engineering properties simultaneously. The results show that a mix proportion containing approximately 90% silty sand plus 10% bentonite soil is the optimal combination in context to the present study. The proposed methodology for optimal decision making to choose appropriate combination of bentonite and silty sand is general in nature and therefore, it can be extended to other problems of selecting mineral compositions.

关键词： silty sand bentonite soil soil mix design multi-attribute decision making

Effect of fire severity on physical and biochemical soil properties in Zagros oak(Quercus brantii Lindl.)forests in Iran

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Journal of Forestry research 2017年第1期28卷 95-104页

作者： M.Heydari A.rostamy F.Najafi D.C.dey Department of Forest Science Faculty of Agriculture and Natural ResourcesIlam UniversityIlamIran Department of Forest Science Islamic Azad UniversityIlam BranchIlamIran Expert in forest Science Ilarn Natural Resources OfficeIlamIran research Forester Northern Research StationUSDA Fores tService202 Natural Resources BldgColumbiaMO 65211USA

Fire affects the physical and chemical properties and soil biological activity of natural ecosystems. This study was conducted in the Miyan Tang region, Ilam Province in western Iran. The study site was 110 hectares, where we sampled soils in areas that were classified by fire severity： low （LS）, high （HS） and medium severity （MS）, and unburned （UB）, which served as the control. In each severity class, 25 transect points were randomly selected for measurement. Around each transect plot center, 3 soil samples were selected randomly and soils collected from the 0 to 20 cm depth were combined into a composite sample that was used in laboratory analysis to represent conditions at that point. Plots in the UB and LS fire classes had similar soil conditions and had higher values of factors such as saturated moisture, organic carbon, carbon dioxide, and silt and clay content. In contrast, plots in the HS and MS fire severity classes were clustered in the positive direction along the first axis that represented gradients in soil acidity, electrical conductivity, cation exchange capacity, accessible phosphorus, accessible potassium, bulk density, and sand. Soil attributes were similar in areas of HS and MS fire severity classes, whereas soil conditions in the LS class and UB controls were most similar. Fire in the LS areas either did not significantly alter the physicalchemical soil properties and microbial basal respiration, or soils were able to recover quickly after being burned.

关键词： Fire severity Oak Soil respiration Physical and chemical soil properties

Prioritizing woody species for the rehabilitation of arid lands in western Iran based on soil properties and carbon sequestration

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Journal of Arid Land 2020年第4期12卷 640-652页

作者： Masoud BAZgIr reza OMIDIPOUr Mehdi HEYDArI Nasim ZAINALI Masoud HAMIDI Daniel C dey Department of Water and Soil Engineering Faculty of AgricultureIlam UniversityIlam ***Iran Department of range and Watershed Management Faculty of Natural Resource and Earth ScienceShahrekord UniversityShahrekord ***Iran Department of Forestry Faculty of AgricultureIlam UniversityIlam ***Iran US Forest Service Northern Research StationColumbiaOM 65211USA

Plants are an important component in many natural ecosystems. They influence soil properties, especially in arid ecosystems. The selection of plant species based on their adaptations to site conditions is essential for rehabilitation of degraded sites and other construction sites such as check-dams. Other factors to be considered in species selection include their effects on soil properties and their abilities to meet other management objectives. The purpose of this study was to assess the effects of native(Populus euphratica Oliv. and Tamarix ramosissima Ledeb.) and introduced(Eucalyptus camaldulensis Dehnh. and Prosopis juliflora(Swartz) DC.) woody species on soil properties and carbon sequestration(CS) in an arid region of Iran. Soil sampling was collected at three soil depths(0–10, 10–20 and 20–30 cm) at the sites located under each woody species canopy and in an open area in 2017. Soil physical-chemical property was analyzed in the laboratory. The presence of a woody species changed soil characteristics and soil CS, compared with the open area. For example, the presence of a woody species caused a decrease in soil bulk density, of which the lowest value was observed under E. camaldulensis(1.38 g/cm^3) compared with the open area(1.59 g/cm^3). Also, all woody species significantly increased the contents of soil organic matter and total nitrogen, and introduced species had more significant effect than native species. The results showed that CS significantly increased under the canopy of all woody species in a decreasing order of P. euphratica(9.08 t/hm^2)>E. camaldulensis(8.37 t/hm^2)>P. juliflora(5.20 t/hm^2)>T. ramosissima(2.93 t/hm^2)>open area(1.33 t/hm^2), thus demonstrating the positive effect of a woody species on CS. Although the plantation of non-native species had some positive effects on soil properties, we recommend increasing species diversity in plantations of native and introduced woody species to provide more diversity for the increased ecosystem

关键词： arid ecosystem carbon sequestration degraded soil restoration reforestation soil management