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Study of temporal and spectral characteristics of the X-ray emission from solar flares

Research in Astronomy and Astrophysics 2018年第10期18卷 33-48页

作者： Veena Choithani Rajmal Jain Arun K.Awasthi Geetanjali Singh Sneha Chaudhari som kumar sharma Dept.of Physics Sh.M.M.Patel Institute of Sciences&ResearchKadi Sarva VishwavidyalayaGandhinagar 382015India CAS Key Laboratory of Geospace Environment Department of Geophysics and Planetary SciencesUniversity ofScience and Technology of ChinaHefei 230026China Physical Research Laboratory NavrangpuraAhmedabad 380009India

Temporal and spectral characteristics of X-ray emission from 60 flares of intensity ≥C class observed by the Solar X-ray Spectrometer （SOXS） during 2003-2011 are presented. We analyze the X-ray emission observed in four and three energy bands by the Si and Cadmium-Zinc-Telluride （CZT） detectors, respectively. The number of peaks in the intensity profile of the flares varies between 1 and 3. We find moderate correlation （R ~=0.2） between the rise time and the peak flux of the first peak of the flare irrespective of energy band, which is indicative of its energy-independent nature. Moreover, the magnetic field complexity of the flaring region is found to be highly anti-correlated （R = 0.61） with the rise time of the flares while positively correlated （R = 0.28） with the peak flux of the flare. The time delay between the peak of the X-ray emission in a given energy band and that in 25-30keV decreases with increasing energy, suggesting conduction cooling is dominant in the lower energies. Analysis of 340 spectra from 14 flares reveals that the peak of differential emission measure （DEM） evolution is delayed by 60-360 s relative to that of the temperature, and this time delay is inversely proportional to the peak flux of the flare. We conclude that temporal and intensity characteristics of flares are dependent on energy as well as the magnetic field configuration of the active region.

关键词： Sun X-rays, gamma rays - Sun magnetic fields - Sun flares - Sun corona

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Comparative efficacy of hyperbaric bupivacaine vs hyperbaric ropivacaine in spinal anesthesia for cesarean section:A metaanalysis

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World Journal of Methodology 2025年第2期15卷 154-165页

作者： Rishi Anand Deb Sanjay Nag Roushan Patel Prashant sharma Vamsi Krishna Uppalapati Umesh kumar Singh Department of Anaesthesiology Tata Main HospitalJamshedpur 831001JhārkhandIndia

BACKGROUND Intrathecal bupivacaine is the traditional anesthetic drug used in spinal anesthesia for caesarean sections(CSs),but ropivacaine has emerged as a potential *** meta-analysis compares the efficacy and safety of intrathecal hyper-baric bupivacaine vs hyperbaric ropivacaine for cesarean *** To systematically evaluate and compare the efficacy and safety of intrathecal hyperbaric bupivacaine and hyperbaric ropivacaine for spinal anesthesia in *** A thorough search of electronic databases was carried out to find pertinent randomized controlled trials(RCTs)comparing intrathecal hyperbaric ropi-vacaine and hyperbaric bupivacaine during ***,Cochrane database,Google Scholar,and Scopus were searched,and papers from January 2000 to January 2024 were deemed eligible and filtered using predetermined inclusion and exclusion *** were assessed for methodological quality,and data were extracted for time to adequate anesthesia(sensory and motor blockade),duration of sensory and motor block,hemodynamic changes and side effect *** standardized mean difference with 95%CI was used for continuous *** variables were assessed using the Mantel-Haenszel test and the random effect model to compute the odds *** Total 8 RCTs were selected from a pool of 119 search results for *** meta-analysis evaluated pooled effect sizes and assessed heterogeneity among the *** primary objective was to compare key outcomes to identify any significant variances in efficacy and safety profiles between two local *** analysis revealed that the difference in the onset of sensory blockade between the two local anesthetics was statistically insignificant(P=0.1586).However,the onset of motor blockade appeared to be faster with bupivacaine(P=0.03589).Additionally,the regression of sensory and motor blockade occurred earlier in the ropivacaine ***,the duration of the first analgesic

关键词： Ropivacaine Bupivacaine Anesthesia Spinal Cesarean section Meta-analysis

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COVID-19 rhapsody:Rage towards advanced diagnostics and therapeutic strategy

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Journal of Pharmaceutical Analysis 2021年第5期11卷 529-540页

作者： Koel Sinha Sutapa som Chaudhury Pramita sharma Bhuban Ruidas Centre for Healthcare Science and Technology Indian Institute of Engineering Science TechnologyShibpurHowrah711103India Department of Zoology Hooghly Mohsin College Affiliated to University of BurdwanHooghly712101India

The deadly global outbreak of coronavirus disease-2019(COVID-19)has forged an unrivaled threat to human *** its profuse impact,initial risk management and therapies are needed,as well as rapid detection strategies alongside treatments with existing drugs or traditional treatments to provide better clinical support for critical *** detection techniques have been considered but do not sufficiently meet the current challenges of effective COVID-19 ***,several modern techniques including point-of-care diagnosis with a biosensor,clustered regularly interspaced short palindromic repeats(CRISPR)-associated proteins that function as nuclease(Cas)technology,next-generation sequencing,serological,digital,and imaging approaches have delivered improved and noteworthy success compared to that using traditional *** drug treatment,plasma therapy,and vaccine development are also ***,alternative medicines including Ayurveda,herbal drugs,homeopathy,and Unani have also been enlisted as prominent treatment strategies for developing herd immunity and physical defenses against *** considered,this review can help develop rapid and simplified diagnostic strategies,as well as advanced evidencebased modern therapeutic approaches that will aid in combating the global pandemic.

关键词： COVID-19 Ayurveda Herd immunity Homeopathy

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Hill slope instability of Nainital City,Kumaun Lesser Himalaya,Uttarakhand,India

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第2期10卷 280-289页

作者： Nirvan Sah Mohit kumar Rajeev Upadhyay som Dutt Department of Geology(CAS) Kumaun UniversityNainital263001India Wadia Institute of Himalayan Geology 33 General Mahadeo Singh RoadDehradun248001India

Nainital City of Kumaun Lesser Himalaya is prone to mass wasting processes during monsoon season,which mischievously triggers the hill slope instability in this region. Slate, dolomitic limestone, silty sandstone and rhythmite of the Krol Formation are the main rock types. The present study focuses on the investigation of slope stability in the region in terms of potential seismicity and landslide. Geological and geotechnical mapping indicates that the major portion of the area is characterized by slope wash materials and buildings. The combination of 3-4 joint sets with one random joint is the main structure at *** major geological structures of this area are Nainital lake fault passing from the center of the lake, Main Boundary Thrust at SW, and Khuriya Fault passing from the SE direction of Nainital City. This work finds that different types of discontinuities(e.g. joints and faults), overburden due to unplanned civil structures,and neotectonic activity in the vicinity of this ara affect the stability of the city. The slate forms the base of the city, dipping slightly towards the lake side along the NW direction, thus accelerating the instability of this area. Rock mass rating(RMR), slope mass rating, factor of safety(FOS) and graphical analysis of the discontinuity for slope kinematics indicate that the study area is a landslide-prone zone. This study can facilitate reducing the risk of human life, and contribute to the ongoing construction works in the area.

关键词： Hill slope instability Himalaya region Wedge failure Rock mass rating(RMR) Factor of safety(FOS)

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Estimation of composite load model with aggregate induction motor dynamic load for an isolated hybrid power system

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Frontiers in Energy 2015年第4期9卷 472-485页

作者： Nitin kumar SAXENA Ashwani kumar sharma Deptment of Electrical Engineering NIT Kumkshetra Haryana 136119 India

It is well recognized that the voltage stability of a power system is affected by the load model and hence, to effectively analyze the reactive power compensation of an isolated hybrid wind-diesel based power system, the loads need to be considered along with the generators in a transient analysis. This paper gives a detailed mathematical modeling to compute the reactive power response with small voltage perturbation for composite load. The composite load is a combination of the static and dynamic load model. To develop this composite load model, the exponential load is used as a static load model and induction motors （IMs） are used as a dynamic load model. To analyze the dynamics of IM load, the fifth, third and first order model of IM are formulated and compared using differential equations solver in Matlab coding. Since the decentralized areas have many small consumers which may consist large numbers of IMs of small rating, it is not realistic to model either a single large rating unit or all small rating IMs together that are placed in the system. In place of using a single large rating IM, a group of motors are considered and then the aggregate model of IM is developed using the law of energy conservation. This aggregate model is used as a dynamic load model. For different simulation studies, especially in the area of voltage stability with reactive power compensation of an isolated hybrid power system, the transfer function AQ/AV of the composite load is required. The transfer function of the composite load is derived in this paper by successive derivation for the exponential model of static load and for the fifth and third order IM dynamic load model using state space model.

关键词： isolated hybrid power system (IHPS) compo- site load model static load dynamic load induction motorload model aggregate load

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Antioxidant and modulatory role of Chlorophytum borivilianum against arsenic induced testicular impairment

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Journal of Environmental Sciences 2012年第12期24卷 2159-2165页

作者： Garima sharma Madhu kumar Cell and Molecular Biology Laboratory Department of ZoologyCentre for Advanced studiesUniversity of RajasthanJaipur 302055India

Arsenic has a suppressive influence on spermatogenesis and induces impairment in male reproductive system due to oxidative stress. The present study was aimed to test the arsenic induced toxicity and protection by Chlorophytum borivilianum. The effect of sodium arsenite （4 mg/（kg body weight （bw）.day）） via double distilled water without or with C. borivilianum （800 mg/（kg ***）） was evaluated in Swiss albino mice for 30 days. The radical scavenging activity of the aqueous C. borivilianum root extract was measured using DPPH （1,1-diphenyl-2-picryl hydrayzyl） radical. Qualitative assessment of various cell types in the testis, sperm count and motility, testicular activity of lipid peroxidation （LPO）, reduced glutathione （GSH）, acid and alkaline phosphatase, cholesterol and serum testosterone were monitored. Arsenic treatment showed a significant increase in LPO, acid and alkaline phosphatase, cholesterol and decrease in sperm count, sperm motility, GSH and serum testosterone. Combined treatment showed significant decrease in LPO, acid and alkaline phosphatase, cholesterol and elevation in sperm count, sperm motility, GSH and serum testosterone. Testicular histopathology showed that C. borivilianum had reduced degeneration of germ cell in the seminiferous tubules and loss of sperms induced by arsenic intoxication. The results thus led us to conclude that administration of C. borivilianum root extract is found to be protective against arsenic induced toxicity.

关键词： DPPH radical assay Chlorophytum borivilianum reduced glutathione lipid peroxidation arsenic testosterone

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Effect of cooling media on bead geometry,microstructure,and mechanical properties of wire arc additive manufactured IN718 alloy

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Advances in Manufacturing 2024年第1期12卷 124-149页

作者： Parveen kumar Satish kumar sharma Ratnesh kumar Raj Singh Department of Mechanical Engineering Thapar Institute of Engineering and TechnologyPatialaPunjab147004India

This work aims to present and explore thermal management techniques for the wire arc additive manufacturing(WAAM)of IN718 *** heat can be mitigated via air or water *** this study,the material was deposited under four different heat-input conditions with air or water *** air cooling,the layer is deposited in a normal atmospheric air environment,whereas with water cooling,the material is deposited inside a water tank by varying the water *** validate the air and water cooling thermal management techniques,IN718 single-pass and multilayer linear walls were deposited using the bidirectional gas metal arc welding based WAAM setup under four different heat input *** the deposition of single layers,the temperature profiles were recorded,and the geometric and microstructural features were *** multilayer wall structures,the mechanical properties(hardness,tensile strength,and elongation)were determined and assessed using the corresponding microstructural features explored through scanning electron microscopy(SEM),energy dispersive spectroscopy(EDS),and electron backscatter diffraction(EBSD)*** microstructure observed through SEM analysis in the building direction was found to be nonhomogenous compared with that in the deposition ***,water cooling was found to govern bead characteristics,such as wall width and *** grain size and anisotropy of the mechanical properties also decreased in the water-cooled ***,water cooling is an economical and efficient method to mitigate excessive heat accumulation in WAAM-deposited IN718.

关键词： Air cooling Water cooling IN718 Bead characteristics Microstructure Electron backscatter diffraction(EBSD)

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PAPR Reduction in NOMA by Using Hybrid Algorithms

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Computers, Materials & Continua 2021年第10期69卷 1391-1406页

作者： Mohit kumar sharma Arun kumar Department of Electronics and Communication Engineering JECRC UniversityJaipur303905India

Non-orthogonal multiple access(NOMA)is gaining considerable attention due to its features,such as low out-of-band radiation,signal detection capability,high spectrum gain,fast data rate,and massive D2D *** may be considered for 5G ***,the high peak-to-average power ratio(PAPR)is viewed as a significant disadvantage of a NOMA waveform,and it weakens the quality of signals and the throughput of the *** this article,we introduce a modified NOMA system by employing a block of wavelet transform,an alternative to FFT(Fast Fourier transform).The modified system combines the details of fractional frequency and time analysis of NOMA *** this correspondence,we utilize an advanced partial transmission scheme(PTS),and selective mapping(SLM),and present a genetic algorithm(GA)for SLM to investigate the peak power performance of a WT-based NOMA *** performance of WT-SLM,WT-PTS,and WT-SLM-GA methods is compared with that of the traditional NOMAbased SLM and PTS *** simulation results demonstrate that the proposed system effectively reduces PAPR in comparison with the traditional schemes.

关键词： PAPR wavelet transform NOMA PTS SLM 5G

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Punjabi DeConverter for generating Punjabi from Universal Networking Language

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Journal of Zhejiang University-Science C(Computers and Electronics) 2013年第3期14卷 179-196页

作者： Parteek kumar Rajendra kumar sharma Department of Computer Science & Engineering Thapar University School of Mathematics & Computer Applications Thapar University

DeConverter is core software in a Universal Networking Language(UNL) system.A UNL system has EnConverter and DeConverter as its two major *** is used to convert a natural language sentence into an equivalent UNL expression,and DeConverter is used to generate a natural language sentence from an input UNL *** paper presents design and development of a Punjabi *** describes five phases of the proposed Punjabi DeConverter,i.e.,UNL parser,lexeme selection,morphology generation,function word insertion,and syntactic *** paper also illustrates all these phases of the Punjabi DeConverter with a special focus on syntactic linearization issues of the Punjabi *** linearization is the process of defining arrangements of words in generated *** algorithms and pseudocodes for implementation of syntactic linearization of a simple UNL graph,a UNL graph with scope nodes and a node having un-traversed parents or multiple parents in a UNL graph have been discussed in this *** cases of syntactic linearization with respect to Punjabi language for UNL relations like 'and','or','fmt','cnt',and 'seq' have also been presented in this *** paper also provides implementation results of the proposed Punjabi *** DeConverter has been tested on 1000 UNL expressions by considering a Spanish UNL language server and agricultural domain threads developed by Indian Institute of Technology(IIT),Bombay,India,as *** proposed system generates 89.0% grammatically correct sentences,92.0% faithful sentences to the original sentences,and has a fluency score of 3.61 and an adequacy score of 3.70 on a 4-point *** system is also able to achieve a bilingual evaluation understudy(BLEU) score of 0.72.

关键词： DeConverter EnConverter Machine translation Universal Networking Language(UNL) Syntactic linearization

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Characterization of optical transitions of Eu^(3+) in lanthanum oxychloride nanophosphor

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Journal of Rare Earths 2011年第4期29卷 345-348页

作者： A. Choubey S. som M. Biswas S.K. sharma Department of Applied Physics Indian School of Mines Dhanbad 826004 India

This paper presented the studies on the optical properties and calculation of spectral parameters of europium doped lanthanum oxychloride nanophosphor for their possible applications in optoelectronic devices. The compound was doped with 0.1 mol% Eu3＋ ions. The X-ray diffraction study of prepared sample suggested the tetragonal structure with particle size in the range of 18–21 nm. The photoluminescence （PL） emission spectra showed the bright emission in orange-red region from 580 to 630 nm. The most intense emission peak at 621 nm was due to transition 5D0→7F2 in energy levels of Eu3＋ ions. The spectral parameters were calculated from the absorption and emission spectra using Judd-Ofelt intensity parameters. The calculated values of the oscillator strength corresponding to the three transitions 7F1→5D1, 7F1→5D2 and 7F0→5D2 observed at 535, 472 and 465 nm in absorption spectra were 0.30×10–6, 1.36×10–6 and 0.63×10–6, respectively. The value of transi- tion probability （A）, stimulated emission cross-section （） and radiative lifetime （τrad） corresponding to 621 nm emission peak （transition 5D0→7F2） were 308 s–1, 1.22×10–21 cm2 and 3.24×10–3 s, respectively.

关键词： X-ray diffraction optical absorption photoluminescence spectral parameters rare earths

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