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Research in Astronomy and Astrophysics 2020年第1期20卷 124-136页

作者： Aftab Ahmad shivani Alka Misra Poonam Tandon Department of Mathematics&Astronomy University of LucknowLucknowIndia Department of Physics University of LucknowLucknowIndia

The three isomers of C2H4O2,viz.,glycolaldehyde(HCOCH2 OH),acetic acid(CH3 COOH)and methyl formate(HCOOCH3),have been detected in copious amounts in the interstellar medium(ISM).The possibility for formation of these molecules through interstellar formaldehyde(HCHO)has been explored by using the quantum chemical approach described by density functional theory(DFT)and second order Moller-Plesset perturbation(MP2)theory with a 6–311 G(d,p)basis set in the gas phase as well as in icy *** associated molecule-molecule interactions have been discussed to study the formation of isomers of C2H4O2 in *** reactions of two formaldehyde molecules exhibit a considerable potential barrier but due to quantum tunneling,these reactions could be possible in *** chemical pathway is exothermic,which gives rise to a high probability for the formation of all three isomers,***,methyl formate and acetic acid,in interstellar *** rotational vibration,centrifugal distortion constants and coupling constants are also calculated and results suggest that the vibrations are harmonic in nature.

关键词： ISM:molecules astrochemistry astrobiology abundances

Fusion of spherical-octupole pairs of colliding nuclei for compact and elongated configurations

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Chinese Physics C 2022年第1期46卷 146-156页

作者： shivani Jain Manoj K.Sharma Raj Kumar School of Physics and Materials Science Thapar Institute of Engineering&TechnologyPatiala-147004PunjabIndia

The deformation and associated optimum/uniquely fixed orientations play an important role in the syn-thesis of compound nuclei via cold and hot fusion reactions,respectively,at the lowest and highest barrier *** choice of optimum orientation(0_(op))for the'cold or elongated'and hot or cormpact'fusion configurations of quadrupole(β_(2))deformed nuclei depends only on the+/-signs ofβ_(2)-deformation[***.G:***.31,631-644(2005)].In our recent study[***.C 101,051601(R)2020],we proposed a new sct of Oopt(iferent from the values reported for quadrupole deformed nuclei)after the inclusion of octupole deformation(up to B3)*** the respective 0op1 of B3-deformed nuclei for cold and hot optimum orientations,we analyzed the im-pact of the soft-and rigid-pear shapes of octupole deformed nuclei on the fusion barrier characterstics(barrier height Vg and barrier position RB).This analysis is applied to approximately 200 spherical-plus B3 deformed nucle-ar partners,that is,^(16)O,^(18)Cat octupole deformed *** with the compact configuration,the elongated fu-sion configuration has a relatively larger impact on the fusion barrier and cross sections ow ing to the inclusion of de-formations up to *** agreement with available experimental data for the^(16)O+^(150)Sm reaction(β_(22)-0.205,β_(32)=0.055)also improves when the optimum orientation degree of freedom is fixed in view of octupole *** reinforces the fact that nuclear structure effects play an important role in the nuclear fusion ***,octu-pole deformed nuclei can be used for the synthesis of heavy and superheavy nuclei.

关键词： nuclear fusion reactions fusion barrier heavy-ion reactions

Formation of cyanoallene(buta-2, 3-dienenitrile) in the interstellar medium: a quantum chemical and spectroscopic study

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Research in Astronomy and Astrophysics 2014年第3期14卷 275-284页

作者： Amresh Singh shivani Alka Misra Poonam Tandon Department of Mathematics & Astronomy University of Lucknow Department of Physics University of Lucknow

The interstellar medium, filling the vast space between stars, is a rich reser-voir of molecular material ranging from simple diatomic molecules to more com-plex, astrobiologically important molecules such as vinylcyanide, methylcyanodiac-cetylene, cyanoaUene, etc. Interstellar molecular cyanoallene is one of the most stableisomers of methylcynoacetylene. An attempt has been made to explore the possibilityof forming cyanoallene in interstellar space by radical-radical and radical-moleculeinteraction schemes in the gaseous phase. The formation of cyanoallene starting fromsome simple, neutral interstellar molecules and radicals has been studied using densityfunctional theory. The reaction energies and structures of the reactants and productsshow that the formation of cyanoallene is possible in the gaseous phase. Both of theconsidered reaction paths are totally exothermic and barrierless, thus giving rise to ahigh probability of occurrence. Rate constants for each step in the formation processof cyanoallene in both the reaction paths are estimated. A full vibrational analysishas been attempted for cyanoallene in the harmonic and anharmonic *** spectroscopic parameters such as rotational constants, rotation-vibrationcoupling constants and centrifugal distortion constants have been calculated.

关键词： astrochemistry techniques: spectroscopic ISM: abundances ISM: molecules

Controlled transition to different proton acceleration regimes:Near-critical-density plasmas driven by circularly polarized few-cycle pulses

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Matter and Radiation at Extremes 2023年第5期8卷 1-18页

作者： shivani Choudhary De Marco Sudipta Mondal Daniele Margarone Subhendu Kahaly AFFILIATIONS 1 ELI-ALPS ELI-HU Non-Profit Ltd.Wolfgang Sandner utca 3Szeged 6728Hungary ELI Beamlines Center Institute of PhysicsCzech Academy of SciencesZa Radnicí835252-41 DolníBrezanyCzech Republic Institute of Physics University of SzegedDóm tér 9H-6720 SzegedHungary

A controlled transition between two different ion acceleration mechanisms would pave the way to achieving different ion energies and spectral features within the same experimental set up,depending on the region of *** on numerical simulations conducted over a wide range of experimentally achievable parameter space,reported here is a comprehensive investigation of the different facets of ion acceleration by relativistically intense circularly polarized laser pulses interacting with thin near-critical-density plasma *** results show that the plasma thickness,exponential density gradient,and laser frequency chirp can be controlled to switch the interaction from the transparent operating regime to the opaque one,thereby enabling the choice of a Maxwellian-like ion energy distribution with a cutoff energy in the relativistically transparent regime or a quasi-monoenergetic spectrum in the opaque ***,it is established that a multispecies target configuration can be used effectively for optimal generation of quasi-monoenergetic ion bunches of a desired ***,the feasibility is demonstrated for generating monoenergetic proton beams with energy peak atℰ≈20–40 MeV and a narrow energy spread ofΔℰ/ℰ≈18%–28.6%confined within a divergence angle of∼175 mrad at a reasonable laser peak intensity of I0≃5.4×10^(20)W/cm^(2).

关键词： acceleration regime circular

Quantum chemical analysis for the formation of glycine in the interstellar medium

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Research in Astronomy and Astrophysics 2013年第8期13卷 912-920页

作者： Amresh Singh shivani Alka Misra Poonam Tandon Department of Mathematics & Astronomy University of Lucknow Department of Physics University of Lucknow

Glycine （C2H5NO2） was the first amino acid to be detected in space by the stardust space probe in Comet Wild2, and is used by living organisms to make proteins. We discuss three different reaction paths for the formation of glycine in interstellar space from some simpler molecules detected in the interstellar medium. The possibility of the formation of glycine in interstellar space is considered by radicalradical and radical-molecule interaction schemes using quantum chemical calculations with density functional theory at the B3LYP/6-31G （d,p） level. In the chemical pathways we discuss, a few reactions are found to be totally exothermic and barrierless while others are endothermic with a very small reaction barrier, thus giving rise to a high probability of forming glycine in interstellar space.

关键词： astrobiology - astrochemistry - ISM: abundances - ISM: molecules

Plasma cascaded solid wastes for possible adsorption of NO_(2)in diesel exhaust

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Waste Disposal and Sustainable Energy 2023年第3期5卷 383-393页

作者： Apoorva Sahu shivani Mishra Preeti Jain Bangalore S.Rajanikanth Department of Electrical Engineering Indian Institute of ScienceBangaloreIndia Department of Electrical Engineering Jabalpur Engineering CollegeJabalpurIndia

Extensive use of fossil fuel has led to an increase in solid and gaseous particulates in the environment,which in turn necessitated newer,effective,and economical control strategies to abate pollutants,particularly gaseous *** the current research work,focus has been placed on utilizing industry wastes to adsorb nitrogen oxides present in diesel engine exhaust,which is pre-treated by *** exhaust from a 5 kW diesel generator is exposed to discharge plasma where the oxidation of nitric oxide to nitrogen dioxide occurs,which is then made to flow through another reactor filled with industry wastes drawn from agriculture,foundry,utility,marine industry,etc.,comprising mulberry waste,rice husk,wheat husk,areca nut husk,sugarcane bagasse,coffee husk,foundry sand,lignite ash,red mud,and oyster *** the adsorption of nitrogen dioxide was observed in all the wastes,reduction of nitric oxide was observed in metallic compound-based industry *** about 184 J/L,specific energy plasma cascaded industrial waste red mud yielded 98%NO_(x)removal efficiency,and that with agriculture rice husk waste yielded 53%NOx ***_(2)/Fe_(2)O_(3)present in industry wastes might have exhibited photo-catalysis in visible light resulting in the possible reduction of NO.A new pathway for recycling the waste can be expected through nitrogen dioxide adsorption,and the results are further discussed with respect to plasma-alone and cascaded plasma adsorbent systems.

关键词： Industry waste Electrical discharge Diesel exhaust Nitrogen oxide reduction Agriculture waste Plasma adsorption

5-Hydroxytryptamine-inhibiting property of Feverfew: role of parthenolide content

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Acta Pharmacologica Sinica 2000年第12期21卷 51-59页

作者： shivani MTTTRA,Aniruddha DATTA,S K SINGH,Amarjit SINGH Research and Development Panacea Biotec Limited P O Lalru 140501 Punjab India Research and Development Panacea Biotec Limited P O Lalru 140501 Punjab India Research and Development Panacea Biotec Limited P O Lalru 140501 Punjab India Research and Development Panacea Biotec Limited P O Lalru 140501 Punjab India

AIM: To study the mechanism of antimigraine activity of Tanacetum parthenium ( Feverfew), its extracts and parthenolide, a component of Feverfew, by observing their effect on 5-HT storage and release, and stimulation of 5-HT2B and 5-HT2A receptors. Also to standardize a dosage form of Feverfew with respect to its parthenolide content. METHODS: Isometric responses to 5-HT and an indirect acting serotonergic, d-fenfluramine, were obtained on rat fundus and ileum. In one set of experiments the effect of dichloromethane extract of Feverfew and parthenolide was observed on the above. The extract was then thermally degraded upto 10 %, 23 %, and 33 % with respect to its parthenolide content by keeping at 60℃ and 75 % relative humidity and the experiments were repeated. In another set of experiments rats were fed with 20 mg/kg Feverfew powder (equivalent to a human dose of 500 μg parthenolide per day) for 30 d or were ip injected with parthenolide (23.4 μg/day) for 7 d. In the same set of experiments one gro

关键词： Tanacetum parthenium Feverfew parthenolide sesquiterpenes lactones stomach fundus ileum serotonin antagonist migraine

D2 analysis for estimating genetic divergence in different clones of Dalbergia sissoo

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Journal of Forestry Research 2016年第5期27卷 1085-1097页

作者： Ashok Kumar S. Ravichandran shivani Dobhal Vijay Kumar Forest Research Institute (Indian Council of Forestry Research and Education) Dehradun India Directorate of Rice Research Rajendra Nagar HyderabadAndhra Pradesh India Research Circle Punjab Forest Department HoshiarpurPunjab India

Genetic divergence was studied in selected 36 genotypes of Dalbergia sissoo Roxb. on the basis of seven morphological parameters. The divergence among genotypes was estimated by Mahalanobis method and genotypes were grouped into clusters by Tocher＇s method. All the genotypes were classified into seven distinct clusters on the basis of seven morphological traits. Cluster 1 was the largest with 25 genotypes followed by Cluster 2 （four genotypes）. Cluster 3, 5, 6 and 7 were the divergent clusters. The D2 analysis revealed that D2 value （39.42） between clone 5040 and clone 201 was recorded maximum. The intra-cluster distance ranged from 0.00 （Cluster 3, 5, 6 and 7） to 3.89 （Cluster 1）, the Cluster 3 （clone 33） was the most divergent cluster with maximum inter cluster distance （13.97） with the Cluster 7. By the divergence analysis, the parents for hybridization from diverse clusters could be selected for heterotic hybrids.

关键词： Dalbergia sissoo Roxb. Genetic divergence Hybridization D2 analysis Heterotic

Corelation Among Soft Tissue Points Namely Maxillary Point, Labrale Superius and Pronasale

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Corelation Among Soft Tissue Points Namely Maxillary Point, ...

作者： shivani GARG 重庆医科大学

学位级别：硕士

Background and objectiveThe aim of the present study was to determine-using the10most recent annual listings of the most beautiful people inpeople’s magazine–whether any measurable esthetic parametercould be extracted from the interrelation among the position ofsoft tissue points namely Maxillary point, Pronasale and Labralesuperius with respect to each other.Materials and MethodsA total of80women, who had been included in the list ofPeople’s magazine,100most beautiful people during the previous10years, were selected from internet database. A modifiedphotogrammetric analysis was performed on the lateral view ofeach subject to obtain the proportional measurements. Thederived measurement was then applied to the lateral photographsof20Chinese female patients with pleasing *** andafter photographs were then judged by a panel of twentyorthodontists and60lay people for any positive improvement inprofile. ResultsResults of this study showed that when upper lip is positionedhorizontally such that its distance from maxillary point andpronasale is in ratio of1.18:1with a standard deviation of0.12,leads to a very esthetic profile.ConclusionIt reveals that prominence of maxillary point should be takeninto consideration while contemplating treatment plan to achievethe most desired horizontal upper lip position and therebyestablishing an esthetic profile.

关键词： Esthetic parameter photogrammetric analysis proportionalmeasurement

Effect of blast inside tunnel on surrounding soil mass,tunnel lining,and superstructure for varying shapes of tunnels

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Underground Space 2021年第6期6卷 619-635页

作者： M.D.Goel shivani Verma Jagriti Mandal Sandeep Panchal Department of Applied Mechanics Visvesvaraya National Institute of Technology(VNIT)Nagpur 440010MaharashtraIndia Department of Mining Engineering Visvesvaraya National Institute of Technology(VNIT)Nagpur 440010MaharashtraIndia

In this study,a finite element(FE)analysis of shallow tunnels exposed to a blast inside the tunnel,with soil as surrounding medium and a structure at ground level,was *** ConWep program,developed by the US Army,was used to simulate blast loading using ABAQUS/Explicit■.Drucker-Prager(D-P)plasticity model,concrete damage plasticity(CDP),and Johnson-Cook(J-C)plasticity models were used to define the behavior of the soil,concrete,and reinforcement,*** analysis was carried out to compare the damages to the superstructure with variation in the cross-sectional shapes of the tunnel under internal blast *** tunnel shapes(circular,rectangular,and horseshoe cross-sections)were considered in the FE *** explosive of 100 kg TNT was located at the center of the cross-section of the *** response of the tunnel in terms of displacement and stress at critical locations was *** results showed that changes in the cross-section of the tunnel affect the stability of the tunnel,even when keeping all other factors *** was observed that the intensity of the stresses was the highest for a rectangular tunnel and lowest for a circular ***,it was also determined that the tunnel with a rectangular cross-section experienced the maximum displacement in the reinforced concrete(RC)lining compared with the horseshoe and circular *** displacement measured at critical structural members of the superstructure was found to be the highest for the tunnel with a rectangular cross-section and lowest for the tunnel with a circular cross-section.

关键词： Blast loading Numerical simulation ConWep Framed superstructure FE analysis ABAQUS/Explicit■