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Assessment and Development of Two phase Turbulent Mixing Models for Subchannel Analysis Relevant to BWR

World Journal of Nuclear Science and Technology 2014年第4期4卷 195-207页

作者： Mohit p. Sharma arun K. Nayak Homi Bhabha National Institute Mumbai India Bhabha Atomic Research Centre Reactor Engineering Division Mumbai India

Determination of turbulent mixing rate of two phase flow between neighboring subchannels is an important aspect of sub channel analysis in reactor rod bundles. Various models have been developed for two phase turbulent mixing rate between subchannels. These models show that turbulent mixing rate is strongly dependent on flow regimes;their validity was examined against specific or limited experiments. It is vital to evaluate these models by comparing the predicted two phase turbulent mixing rate with available experimental data conducted for various subchannel geometries and operating conditions. This paper describes evaluation of different models for two phase turbulent mixing rate for both gas and liquid phase against large range of experimental data which are obtained from various subchannel geometries. The results indicate that there is large discrepancy between the predicted and experimental data for turbulent mixing rate. This paper provides important shortcoming of the previous work and need for the development of a new model. In the view of this, a two phase flow model is presented, which predicts both liquid and gas phase turbulent mixing rate between adjacent sub channels of reactor rod bundles. The model presented here is for slug churn flow regime, which is dominant as compared to the other regimes like bubbly flow and annular flow regimes, since turbulent mixing rate is the highest in slug churn flow regime. The present model has been tested against low pressure and temperature air-water and high pressure and temperature steam-water experimental data found that it shows good agreement with available experimental data.

关键词： Subchannel Analysis Two phase Turbulent Mixing Model Turbulent Mixing Rate

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physicochemical properties,antioxidant and anti-inflammatory activities of coumarin-carbonodithioate hybrids

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Asian pacific Journal of Tropical Biomedicine 2018年第4期8卷 201-206页

作者： Suresh S.Kumbar Kallappa M.Hosamani arun K.Shettar Department of Studies in Chemistry Kamatak University p G Department of Studies in Biotechnology and Microbiology Karnatak University

Objective:To study physicochemical properties,antioxidant and anti-inflammatory activities of coumarin-carbonodithioate ***:The substituted 4-bromomethyl coumarins were synthesized in first step by the *** the reaction of substituted coumarins(a-e)with potassium O-ethyl/methyl carbonodithioate(1)by using absolute ethanol as solvent,afforded coumarin-carbonodithioate(1a-1j)derivatives under microwave irradiation and the conventional *** spectroscopic analysis was used for the characterization of coumarin *** title(1a-1j)compounds were confirmed by spectroscopic *** property was evaluated by using DppH free radical-scavenging ability assay method and anti-inflammatory activity was evaluated by protein denaturation procedure using diclofenac sodium as a ***-silico toxicity was predicted with LD_(50)value and bioactivity score was also calculated for all the ***:All coumarin(1a-1j)compounds exhibited promisingin-vitro antioxidant and anti-inflammatory properties in comparison to standard *** tested compounds were used for evaluating their physicochemical properties as set by Lipinski *** was observed that the synthesized compounds followed rule of five,indicating more'drug-like'***:All the screened coumarin-carbonodithioates display promising in vitro antioxidant and antiinflammatory *** the physicochemical properties of coumarin derivatives,it is found that none of the compounds violate the Lipinski rule and they fall well in the range of rule of *** is concluded that the coumarin-carbonodithioate hybrids act with more'drug-like'nature.

关键词： physicochemical properties Coumarin-carbonodithioates In vitro antioxidant activity In vitro anti-inflammatory activity

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Ecological variables influencing the diversity and distribution of macrolichens colonizing Quercus leucotrichophora in Uttarakhand forest

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Journal of Mountain Science 2018年第2期15卷 307-318页

作者： Shashi UpADHYAY arun K.JUGRAN Yogesh JOSHI Renu SUYAL Ranbeer S.RAWAL Lichenology laboratory S.S.J.Campus Kumaun University Biodiversity Conservation & Management Ecosystem Services and Climate Change Group G.B.Pant National Institute of Himalayan Environment and Sustainable Development G.B.pant National Institute of Himalayan Environment and Sustainable Development Garhwal Unit

Ecological variables play a significant role in determining the diversity and distribution of any living organism on earth. Lichens are not exceptional and are quite sensitive in comparison to other organisms; hence the present study focuses on the impact of ecological variables on the diversity and distribution of epiphytic macrolichens colonizing Quercus leucotrichophora across eight different sites(50 m × 50 m) in Thal Ke Dhar forest, Kumaun Himalaya, Uttarakhand, India. For sampling of macrolichens, 200 trees(25 trees from each site) of *** were selected from each site and five quadrats of 5 cm × 10 cm(1000 quadrats in totality) were drawn at the tree trunk. From all the sampled trees, a total of 54 species of epiphytic macrolichens belonging to 18 genera and five families were recorded. Various ecological variables, namely altitude, aspect, slope, diameter at breast height(DBH), and lopping percent(partial cutting of the twigs as disturbance), were also analyzed to investigate their influence on macrolichen species composition and distribution pattern in the study area. For the determination of relationships between these variables, statistical analysis, namely pearson's Correlation Coefficient, polynomial regression analysis and principal Component Analysis(pCA)were performed. Out of all variables, lopping was significantly correlated to species richness of epiphytic macrolichens(0.712~*, ppearson's Correlation *** of having high anthropogenic pressure or impact through lopping, the maximum number of macrolichen species was recorded at elevation 2267 meter above sea level(m asl). The present study revealed that besides other ecological variables,lopping practices can act as a key parameter incontrolling the diversity and distribution not only of epiphytic macrolichens but also of other life forms such as bryophytes, pteridophytes, insects, birds *** can be either negatively or positively correla

关键词： Conservation Epiphytic macrolichens Kumaun Himalaya Lopping Quercus Banj oak

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Comprehensive Record of Megafossils from the Rajmahal Basin, Jharkhand, India

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International Journal of Geosciences 2023年第4期14卷 316-328页

作者： arun Joshi Council of Scientific and Industrial Research (CSIR) New Delhi India Botany Department S.G.R.R. (P.G.) College Dehradun India

The study provides the first comprehensive record of the plant megafossils mainly Glossopteris flora from the Barakar Formation, Rajmahal Open Cast Mine, Rajmahal Basin, Jharkhand. The assemblage is composed of pteridophytes and gymnosperms. The pteridophytes comprise Equisetalean axes (order Equisetales), whereas, gymnosperms include nine species of Glossopteris including Glossopteris communis, G. damudica, G. gigas, G. indica, G. lanceolatus, G. longicaulis, G. oldhamii, G. taenioides, G. tenuifolia along with Vertebraria indica and Noeggerathiopsis hislopi. The present investigation adds to the knowledge of the Glossopteris flora of India, especially that of the Rajmahal Basin from where the plant fossil records are sporadic. The area is a treasure for palaeobotanical studies as evinced by different fossil localities. However, the localities are degraded by mining activities performed by private companies and hence systematic investigation for such vegetation is vital to create a palaeobotanical database before their complete degradation. The floral assemblage compares with earlier known assemblages, recorded from the Barakar Formation of other Lower Gondwana basins of peninsular India. .

关键词： Glossopteris Flora Barakar Formation Rajmahal Basin Gondwana

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Design of an Efficient Cooperative Spectrum for Intra-Hospital Cognitive Radio Network

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Computers, Materials & Continua 2021年第10期69卷 35-49页

作者： Abhinav Adarsh Basant Kumar Manoj Gupta arun Kumar Aman Singh Mehedi Masud Fahad A.Alraddady Department of ECE MNNIT AllahabadPrayagraj211004India Department of ECE JECRC UniversityJaipur303905India Computer Science and Engineering Lovely Professional UniversityPunjab144411India Department of Computer Science College of Computers and Information TechnologyTaif UniversityP.O.Box 11099Taif21944Saudi Arabia Department of Computer Engineering College of Computers and Information TechnologyTaif UniversityP.O.Box 11099Taif21944Saudi Arabia

This paper presents a new low delay centralized cooperative spectrum sensing method based on dynamic voting rule using multiple threshold level,for indoor hospital environment,where fading and direct path loss both are together responsible for variation in signal *** the proposed algorithm,weights of Cognitive Radios(CRs)in terms of assigned votecount are estimated based on the sensed energy values with respect to multiple fixed threshold levels,so that the direct path loss can be dealt without further increasing the error,which occurs due to *** indoor hospital like environment,Rician fading model is more ***,formulation,evaluation and analysis of various sensing performance parameters have been carried out considering Rician fading *** analysis and tradeoff among three optimum parameters-energy threshold,total number of CRs participating in sensing and total error rate,are presented with respect to signal to noise ratio(SNR).Finally,the Monte Carlo simulation is designed and implemented considering the two conditions-only fading environment and fading along with direct path loss *** can be observed that in both cases,the proposed spectrum sensing rule outperforms the other contemporary rules.

关键词： Cognitive radio direct path loss spectrum sensing health care

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Optimized Resource Allocation for IoT-D2D Communication Using WSN

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Computer Systems Science & Engineering 2023年第5期45卷 1789-1804页

作者： S.arun Mozhi Selvi Roobaea Alroobaea Saeed Rubaiee Abdulkader S.Hanbazazah Department of Computer Science and Engineering Holy Cross Engineering CollegeVagaikulam628851Tamil NaduIndia Department of Computer Sceience College of Computers and Information TechnologyTaif UniversityP.O.Box 11099Taif 21974Saudi Arabia Department of Industrial and Systems Engineering College of EngineeringUniversity of JeddahJeddah21959Saudi Arabia

The need for a strong system to access radio resources demands a change in operating frequency in wireless networks as a part of Radio Resource Management(RRM).In the fifth-generation(5G)wireless networks,the capacity of the system is expected to be enhanced by Device-to-Device(D2D)*** cooperation and Resources Allocation(RA)in the development of Internet of Things(IoT)enabled 5G wireless networks are investigated in this *** radio RA methods for D2D communication while not affecting any Mobile Users’(MU)communication is the main challenge of this *** performance goals such as practising equality in the rates of user data,increasing Network Throughput(NT),and reducing End-to-End Delay(EED)are achieved by *** study undertaken on optimising performance for various wireless networks is focused on in this research *** a polynomialtime proportional Fair Resource Allocation Method(pFRAM),which considers the MU’s rate requirements,is the prime objective of this *** Resource Allocation Method(RAM)can be used by the proposed method for MU,and the time and differing location channel conditions are the factors to be adapted *** more than one resource block is allowed by our pFRAM to a D2D *** automatic maintenance of battery-less IoT wireless devices’energy level is done potentially using an Extensible Energy Management System(EEMS).Finally,the device’s Node Transmission power(NTp)can be managed using an Energy-Saving Algorithm(ESA)designed in this work for Node Uplink Data Transmission(NUDT).The trade-off between the packet Loss Rate(pLR)and NTp is balanced by the *** cost of NUDT’s average Energy Consumption(EC)is reduced by locating the optical *** order to free much bandwidth for wireless information,NUDT conserves the harvested energy for minimising Radio Frequency(RF)Energy Transmission(ET).MATLAB simulations are used to assess the proposed *** IoT device’s NTp is managed using

关键词： IoT energy transmission WSN mobility resource allocation

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Experimental Investigation on Fuel Coolant Interaction Using Simulant Ceramic Melts in Water: Insights and Conclusions

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World Journal of Nuclear Science and Technology 2020年第4期10卷 139-157页

作者： Nitendra Singh arun K. Nayak parimal p. Kulkarni Homi Bhabha National Institute Mumbai India Bhabha Atomic Research Centre Reactor Engineering Division Mumbai India

Steam explosion is one of the crucial and poorly understood phenomena which may occur during severe accident scenario and may lead to containment failure. In spite of several experimental and analytical studies, the root cause of steam explosion has not been understood. Recent claims in the literature suggest that the presence of fine fragmentation during steam explosion causes its occurrence. In order to investigate this and understand the root cause of steam explosion, series of experiments were performed with 50 g to 2500 g of CaO-B2O3, a corium simulant in 4.5 litre of water. It was observed that steam explosion may occur even in the absence of fine fragments, which is contrary to the claims in the literature. To investigate further, conversion efficiency analysis was performed. This suggested that the amount of thermal energy converted to mechanical energy is more important deciding factor in explaining the occurrence of steam explosion. The present study discusses the importance of conversion efficiency in deciding steam explosion and also gives a new perspective to look at steam explosion phenomenology.

关键词： Severe Accident Core Catcher Steam Explosion Fuel Coolant Interaction Fragmentation

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Systematic study of odd-mass^151-161pm and^154,156pm isotopes using projected shell model

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Chinese physics C 2020年第9期44卷 142-153页

作者： Veerta Rani preeti Verma Suram Singh Manvi Rajput arun Bharti G.H.Bhat J.A.Sheikh Department of physics and Astronomical Sciences Central University of JammuSambaJ&K181143India Department of physics University of JammuJammu180001India Department of physic S.P.CollegeCluster University Srinagar190001India Cluster University Srinagar J&K190001India

Inspired by the availability of recent experimental as well as theoretical data on the energy levels of odd-mass^151-161pm and odd-odd^154,156pm,we applied the theoretical framework of the projected shell model to further understand the nuclear structure of these *** calculations closely reproduced the experimental data reported for the yrast bands of these isotopes by assuming an axial(prolate)deformation of^*** properties along the yrast line,such as transition energies and transition probabilities,have also been *** diagrams are plotted to understand their intrinsic multi-quasiparticle structure,which turn out to be dominated by 1-quasiparticle bands for the odd-mass pm isotopes and 2-quasiparticle bands for the doubly-odd pm isotopes under *** present study not only confirms the recently reported experimental/theoretical data,but also extends the already available information on the energy levels and adds new information regarding the reduced transition probabilities.

关键词： projected shell model yrast spectra band diagram transition energies reduced transition probabilities

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Spectral characteristics of banded iron formations in Singhbhum craton,eastern India:Implications for hematite deposits on Mars

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Geoscience Frontiers 2016年第6期7卷 927-936页

作者： Mahima Singh Jayant Singhal K.arun prasad V.J.Rajesh Dwijesh Ray priyadarshi Sahoo Department of Earth and Space Science Indian Institute of Space Science and TechnologyValiamala P.O.Thiruvananthapuram 695 547India physical Research Laboratory NavrangpuraAhmedabad 380009India Geological Survey of India State Unit:OdishaNuipalliBhubaneswar 751012India

Banded iron formations （BIFs） are major rock units having hematite layers intermittent with silica rich layers and formed by sedimentary processes during late Archean to mid proterozoic time. In terrestrial environment, hematite deposits are mainly found associated with banded iron formations. The BIFs in Lake Superior （Canada） and Carajas （Brazil） have been studied by planetary scientists to trace the evolution of hematite deposits on Mars. Hematite deposits are extensively identified in Meridiani region on Mars. Many hypotheses have been proposed to decipher the mechanism for the formation of these deposits. On the basis of geomorphological and mineralogical studies, aqueous environment of deposition is found to be the most supportive mechanism for its secondary iron rich deposits. In the present study, we examined the spectral characteristics of banded iron formations of Joda and Daitari located in Singhbhum craton in eastern India to check its potentiality as an analog to the aqueous/marine environment on Mars. The prominent banding feature of banded iron formations is in the range of few millimeters to few centimeters in thickness. Fe rich bands are darker （gray） in color compared to the light reddish jaspilitic chert bands. Thin quartz veins （〈4 mm） are occasionally observed in the handspecimens of banded iron formations. Spectral investigations have been conducted in VIS/NIR region of electromagnetic spectrum in the laboratory conditions. Optimum absorption bands identified include 0.65, 0.86, 1.4 and 1.9 μm, in which 0.56 and 0.86 μm absorption bands are due to ferric iron and 1.4 and 1,9 μm bands are due to OH/H2O. To validate the mineralogical results obtained from VlS/NIR spectral radiometry, laser Raman and Fourier transform infrared spectroscopic techniques were utilized and the results were found to be similar. Goethite-hematite association in banded iron formation in Singhbhum craton suggests dehydration activity, which has altered the primary iron ox

关键词： Banded iron formation Singhbhum craton VIS/NIR spectroscopy Raman spectroscopy Terrestrial analog Mars

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Saponins isolated from roots of Chlorophytum borivilianum reduce acute and chronic inflammation and histone deacetylase

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Journal of Integrative Medicine 2015年第1期13卷 25-33页

作者： Anirudha A.Lande Shirishkumar D.Ambavade Uma S.Swami prafulla p.Adkar prashant D.Ambavade arun B.Waghamare Department of pharmacology JSPM's Jayawantrao Sawant College of Pharmacy and Research University of Pune Haffkine Biopharmaceutical Corporation Ltd.

OBJECTIVE： The roots of Chlorophytum borivilanum are used in traditional medicine for the treatment of arthritis and inflammation. The aim of the work was to evaluate the anti-inflammatory activity of isolated saponins from Chlorophytum borivilianum （ISCB）. METHODS： The ISCB was screened using the carrageenan-induced paw edema, histamine-induced paw edema, cotton pellet-induced granuloma, and Freund＇s adjuvant-induced arthritis in rats at orally administered doses of 3, 10, and 30 mg/kg. Effect of ISCB on histone deacetylase （HDAC） level was measured by the HDAC assay at the highest dose （30 mg/kg）. RESULTS： The results showed that the ISCB significantly reduced carrageenan-induced inflammation, histamine-induced inflammation, cotton pellet-induced granuloma and Freund＇s adjuvant-induced arthritis in rats. The ISCB at a dose of 30 mg/kg significantly inhibited HDAC level in rat paw tissue. CONCLUSION： It is concluded that saponins isolated from roots of C. borivilianum possess anti- inflammatory and anti-arthritic properties. ISCB may act by inhibiting histamine, prostaglandin and HDAC. This suggests that ISCBs have potential for therapeutic use in the treatment of inflammation and arthritis

关键词： Chlorophytum borivilianum plants, medicinal saponin carrageenan inflammation arthritis histon deacetylase rats

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