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The Analysis of Interplanetary Shocks Associated with Six Major Geo-Effective Coronal Mass Ejections during Solar Cycle 24

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International Journal of Astronomy and Astrophysics 2019年第3期9卷 191-199页

作者： Shirsh Lata Soni Prithvi Raj Singh Bharti Nigam Radhe Syam Gupta pankaj kumar shrivastava Department of Physics Govt. P.G. College Satna India Department of Physics APS University Rewa India Department of Physics Govt. P.G. Model Science College Rewa India

A Coronal Mass Ejection (CME) is an ejection of energetic plasma with magnetic field from the Sun. In traversing the Sun-Earth distance, the kinematics of the CME is immensely important for the prediction of space weather. The objective of the present work is to study the propagation properties of six major geo-effective CMEs and their associated interplanetary shocks which were observed during solar cycle 24. These reported CME events produced intense geo-magnetic storms (Dst > 140 nT). The six CME events have a broad range of initial linear speeds ~600 - 2700 km/sec in the LASCO/SOHO field of view, comparing two slow CMEs (speed ~579 km/sec and 719 km/sec), three moderate speed CMEs (speed ~1366, 1571, 1008 km/sec), and one fast CME (speed ~2684 km/sec). The actual arrival time of the reported events is compared with the arrival time calculated using the Empirical Shock Arrival model (ESA model). For acceleration estimation, we utilize three different acceleration-speed equations reported in the previous literatures for different acceleration cessation distance (ACD). In addition, we compared the transit time estimated using the second-order speed of CMEs with observed transit time. We also compared the observed transit time with transit time obtained from various shock arrival model. From our present study, we found the importance of acceleration cessation distance for CME propagation in interplanetary space and better acceleration speed for transit time calculation than other equations for CME forecasting.

关键词： Coronal Mass Ejection (CME) IP Shock Geomagnetic Strom

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Latitudinal Distribution of Solar Flares and Their Association with Coronal Mass Ejections

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Chinese Journal of Astronomy and Astrophysics 2005年第2期5卷 198-202页

作者： pankaj K.shrivastava Neelam Singh Post Graduate Department of Physics Govt.Model Science College Rewa (M.P.) 486001 India. Department of Physics Government New Science CollegeRewa (M.P.) India

Major solar flare events have been utilised to study the latitudinal frequency distribution of solar flares in northern and southern hemispheres for the period of 1986 to 2003. A statistical analysis has been performed to obtain the correlation between Coronal Mass Ejections (CMEs) and Forbush decrease (Fds) of cosmic ray intensity. Almost the same flares distribution in both hemispheres is found in association with CMEs. In a further analysis, it is noted that a larger number of CME-associated solar flares located in the northern hemisphere are found to be more effective in producing Forbush decreases.

关键词： Solar flares - coronal mass ejections - Forbush decrease

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Numerical Algorithm Based on Quintic Nonpolynomial Spline for Solving Third-Order Boundary Value Problems Associated with Draining and Coating Flows

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Chinese Annals of Mathematics,Series B 2012年第6期33卷 831-840页

作者： pankaj kumar SRIVASTAVA Manoj kumar Department of Mathematics Jaypee Institute of Information Technology Department of Mathematics Motilal Nehru National Institute of Technology

A numerical algorithm is developed for the approximation of the solution to certain boundary value problems involving the third-order ordinary differential equation associated with draining and coating flows. The authors show that the approximate so- lutions obtained by the numerical algorithm developed by using uonpolynomial quintic spline functions ave better than those produced by other spline and domain decomposition methods. The algorithm is tested on two problems associated with draining and coating flows to demonstrate the practical usefulness of the approach.

关键词： Third-order boundary value problem Spline functions Nonpolynomial quartic spline Nonpolynomial quintic spline Draining and coating flows

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A comprehensive review of the influence of physicochemical properties of biodiesel on combustion characteristics,engine performance and emissions

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Journal of Traffic and Transportation Engineering(English Edition) 2021年第4期8卷 510-533页

作者： Tikendra Nath Verma pankaj shrivastava Upendra Rajak Gaurav Dwivedi Siddharth Jain Ali Zare Anoop kumar Shukla Puneet Verma Department of Mechanical Engineering Maulana Azad National Institute of Technology(MANIT)Bhopal 462007India Department of Mechanical Engineering Prestige Institute of Engineering Management and ResearchIndore 452010India Department of Mechanical Engineering Rajeev Gandhi Memorial College of Engineering and TechnologyNandyal 518501India Energy Centre Maulana Azad National Institute of Technology(MANIT)Bhopal 462007India Department of Mechanical Engineering College of Engineering Roorkee(COER)Roorkee 247667India Flow Aerosols and Thermal Energy(FATE)Research GroupSchool of EngineeringDeakin UniversityBurwoodVIC 3216Australia Department of Mechanical Engineering Amity UniversityNoida 201313India School of Chemistry Physics and Mechanical EngineeringQueensland University of TechnologyBrisbaneQLD 4001Australia

Energy is a basic requirement for development in the *** continuously rising demand for energy resources and the fast depletion of fossil fuel is raises researcher's concern to focus on alternative sources of energy that can replace the shortage of fossil fuels *** is recognized as one of the potential alternative renewable energy fuels that can be easily available in a wide range in every part of the *** paper reviews biodiesel's prospect and focuses on the different fuel properties(physicochemical)of 100 biodiesels from first-,second-and third-generation followed by the evaluation of CI engine *** has been observed that the fuel properties of first-,second-and third-generation biodiesel are compatible with the ASTM *** present paper discussed the potential of various generations of biodiesel feedstocks from production *** paper also examined many aspects of these feedstocks which include different biodiesel feedstock sources,biodiesel conversion technology,and second-generation biodiesel performance and emission *** of the studies showed that biodiesel derived from plant feedstock is costly than ***,more influence is to be given to non-edible ***,the engine characteristics are shown promising behavior with biodiesel and a slight increase in NOX is also reported on using various biodiesel.

关键词： Biodiesel Physicochemical Combustion Ignition Emission

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Secondary Silicates as a Barrier to Carbon Capture and Storage in Deccan Basalt

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Acta Geologica Sinica(English Edition) 2020年第3期94卷 861-876页

作者： Amit kumar J.P. shrivastava Department of Geology University of DelhiDelhi 110007India

Investigating the immobilization of CO2,previous basalt-water-CO2 interaction studies revealed the formation of carbonates over a short period,but with the extensive formation of secondary silicates(SS).The mechanisms involved in these processes remain unresolved,so the present study was undertaken to understand secondary mineral formation *** and Rietveld refinement data for neo-formed minerals show a drastic decrease in the Ca-O bond length,with the calcite structure degenerating after 80 h(hours).However,SEM images and EDS data revealed that a longer interaction time resulted in the formation of chlorite and smectite,adjacent to basalt grains which prevent basaltwater-CO2 interaction to form carbonates,thus restricting carbonate *** a result of this,the CO2 mineralization rate is initially high(till 80 h),but it later reduces *** is evident that,for such temperature-controlled transformations,low temperature is conducive to minimizing SS surface coating at the time of mineral carbonation.

关键词： basalt-water-CO2 interaction carbon capture and storage CO2 mineralization leachate chemistry normalized mass loss secondary silicates

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p-TSA-catalyzed one-pot synthesis and docking studies of some 5H-indeno[ 1,2-b]quinoline-9,11 (6H,10H)-dione derivatives as anticonvulsant agents

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Chinese Chemical Letters 2016年第5期27卷 721-725页

作者： Kamaal Ahmed Balkrishna Dubey Sayyed Nadeem Birendra shrivastava pankaj Sharma Department of Pharmaceutical Chemistry TIT College of Pharmacy Anand Nagar Bhopal 462021 Madhya Pradesh India Department of Pharmacology Technocrats Institute of Technology-Pharmacy Anand Nagar Bhopal Modhya Pradesh 462021 India School of Pharmaceutical Sciences Jaipur National University Jaipur Rajasthan India

The present work describes a facile, one-pot three component environment friendly, green synthesis of a series of 5-（4-methoxyphenyl）-7,7-dimethyl-10-phenyl-7,8-dihydro-SH-indeno[ 1,2-b]quinoline- 9,11 （6H,10H）-dione derivatives 8（a-n）. 1,3-indanedione, awl-aldehyde and enaminone was thoroughly ground in the presence of catalytic amount of p-toluene sulfonic acid （p-TSA） to give the titled compounds in good yields. All the synthesized derivatives were evaluated for their anticonvulsant activity using the maximal electroshock （MES） method with phenytoin as a standard drug along with their neurotoxicity effect. Derivatives 8b, 8e and 8k exhibited significant anticonvulsant activity （P 〈 0.001）. The neurotoxicity study clearly revealed that all the tested compounds are non-toxic at a dose of 40 mg/kg. The molecular modeling studies also predicted good binding interactions of most active molecules with the serotonin 5-HT2A receptor. Therefore, it can be safely concluded that synthesized derivatives 8（a-n） would represent useful leads for further investigation in the development of a new class of anticonvulsant agents.

关键词： 5H-Indeno[1 2-b]quinoline One potp-toluene sulfonic acid (p-TSA) Anticonvulsant activity Molecular docking

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Flow past a bluff body subjected to lower subcritical Reynolds number

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Journal of Ocean Engineering and Science 2020年第2期5卷 173-179页

作者： pankaj kumar Santosh kumar Singh Department of Mechanical Engineering SRM Institute of Science and TechnologyKattankulathur 603203India

The paper aimed to study the flow structure at the wake of the bluff body with altered blockage ratio(BR)keeping the fixed aspect ratio(AR).The study was conducted by a finite volume technique using commercial software *** CFD analysis of the bluff body is mainly subjected to the lower subcritical Reynolds number range(5000 to 15,000)along with blockage ratio as an important *** flow parameters such as drag coefficient,pressure,and kinetic energy variations are analyzed here for the Reynolds number(Re)and *** was observed that at fixed Re,t he drag coefficient(C_(D))increases with an increase in the BR while decrease with increasing Re for a fixed value of BR.

关键词： Blockage ratio Bluff body Drag coefficient Reynolds number

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Pichia as yeast cell factory for production of industrially important bio-products:Current trends,challenges,and future prospects

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Journal of Bioresources and Bioproducts 2023年第2期8卷 108-124页

作者： Akansha shrivastava Mamta Pal Rakesh kumar Sharma Department of Biosciences Manipal University JaipurJaipur 303007India Sardar Swaran Singh National Institute of Bio-Energy Jalandhar 144601India

Yeast has been used as a cell factory for thousands of years to produce a wide variety of com-plex biofuels,bioproducts,biochemicals,food ingredients,and *** a variety of biotechnological production hosts,a few specific genera of yeast have proven *** developments in metabolic engineering and synthetic biology provide a workable long-term supply solution for these *** this review,we have covered recent advances in the design of yeast cell factories for the synthesis of terpenoids,alkaloids,phenylpropanoids,and other natural chemicals,primarily focusing on Pichia ***-edge solutions involving genetic and process engineering have also been ***,the review summarized recent advancements and challenges in synthetic and systems biology,as well as initiatives in metabolic engineering aimed at commercializing non-conventional yeasts like *** processes used in non-traditional yeasts to produce enzymes,therapeutic proteins,lipids,and metabolic products for industrial applications were thoroughly elaborated.

关键词： Natural product Pichia Non-conventional yeast Biosynthesis System biology Synthetic biology

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Particle Swarm Optimization Based Support Vector Regression for Blind Image Restoration

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Journal of Computer Science & Technology 2012年第5期27卷 989-995页

作者： Ratnakar Dash pankaj kumar Sa Banshidhar Majhi Computer Science and Engineering Department National Institute of Technology RourkelaRourkela 769008India

This paper presents a swarm intelligence based parameter optimization of the support vector machine （SVM） for blind image restoration. In this work, SVM is used to solve a regression problem. Support vector regression （SVR） has been utilized to obtain a true mapping of images from the observed noisy blurred images. The parameters of SVR are optimized through particle swarm optimization （PSO） technique. The restoration error function has been utilized as the fitness function for PSO. The suggested scheme tries to adapt the SVM parameters depending on the type of blur and noise strength and the experimental results validate its effectiveness. The results show that the parameter optimization of the SVR model gives better performance than conventional SVR model as well as other competent schemes for blind image restoration.

关键词： image restoration support vector regression particle swarm optimization

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Trace elemental signatures and mineral chemistry of clays associated with the alteration halos of the Paleoproterozoic U mineralization in Bijawars of the Sonrai Basin,Central India

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Acta Geochimica 2020年第3期39卷 365-386页

作者： Surendra kumar Jha Rashmi Sharma Jaya Prakash shrivastava University of Delhi DelhiIndia Department of Cement Technology A.K.S.UniversitySatnaMPIndia

Paleoproterozoic Bijawars of the Sonrai basin consists of(a) Sonrai(mostly carbonate carbonaceous shale and phosphatic breccia) and(b) Solda Formations(commonly chloritic and ferruginous shale) with well-developed clay-organo-rich facies,often marked with hydrothermal *** studies revealed abundance order of kaolinite> chlorite> illite> smectite;and kaolinite> illite> chlorite in clay(0.2-2.0 μm) fractions separated from the Sonrai and Solda Formations,*** understand atomic substitutions and trace elemental concentrations,clay minerals were analyzed by fusion ICPMS and *** normalized data plots show U,Th,Rb,Ba,Pb Sr,and large-ion lithophiles enrichment,whereas,Bandai sandstone and Rohini carbonate clays show HREE enrichment with asymmetrical patterns,similar to those reported from the well-established McArthur River,Cigar Lake,and Sue UTUD of *** Rohni carbonate,chondrite-normalized REE data plots revealed M shape REE patterns,ascribed to Gd-Tb-Dy-Ho tetrad effect and anomalous Y,Zr,and Hf *** to HREE incorporation in the clay inter-layers,linear and flattened REE trends were *** REE patterns associated with the highly altered chlorite and illite represent negative Eu anomaly related to the dilational nature of the uraninite structure and is suggestive of anoxic conditions.

关键词： Bijawars Sonrai basin Clays REE patterns Uranium mineralization

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