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Periodic Orbits in the Photogravitational Restricted Problem When the Primaries Are Triaxial Rigid Bodies

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International Journal of Astronomy and Astrophysics 2016年第1期6卷 111-121页

作者： preeti jain Rajiv Aggarwal Amit Mittal Abdullah Department of Mathematics A.R.S.D. College University of Delhi New Delhi India Department of Mathematics Sri Aurobindo College University of Delhi New Delhi India Department of Mathematics College of Science in Zulfi Majmaah University Riyadh KSA

We have studied periodic orbits generated by Lagrangian solutions of the restricted three-body problem when both the primaries are triaxial rigid bodies and source of radiation pressure. We have determined periodic orbits for different values of (h is energy constant;μ is mass ratio of the two primaries;are parameters of triaxial rigid bodies and are radiation parameters). These orbits have been determined by giving displacements along the tangent and normal at the mobile co-ordinates as defined in our papers (Mittal et al. [1]-[3]). These orbits have been drawn by using the predictor-corrector method. We have also studied the effect of triaxial bodies and source of radiation pressure on the periodic orbits by taking fixed value of μ.

关键词： Restricted Three-Body Problem Periodic Orbits Triaxial Rigid Body Radiation Pressure

An Evaluation on Antioxidant Activity, Total Phenolic and Total Flavaonoid Contents of Extracts from <i>Adina cordifolia</i>(Roxb.)

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American Journal of Plant Sciences 2015年第5期6卷 633-639页

作者： Md. Ali Akbar Hossain Md. Selim Hossain Kaniz Fatema Benazir Ahmed Siddique Hanif Sikder Md. Sohel Sarker preeti jain Department of Pharmaceutical Sciences North South University Bashundhara Dhaka Bangladesh Department of Pharmacy Gono Bishwabidyalay (University) Savar Dhaka Bangladesh Department of Pharmacy University of Asia Pacific Dhanmondhi Dhaka Bangladesh

In this study, in vitro antioxidant activity, total phenolic content and concentration of flavonoids of four different extracts of Adina cordifolia (Roxb.) were determined using spectrophotometric methods. Antioxidant activity of extracts was expressed as percentage of DPPH radicals’ inhibition and IC50 values (μg/ml). IC50 values ranged from 20.39 to 38.96 μg/ml. The total phenolic content ranged from 17.48 to 20.83 mg/g of dry weight of extract, expressed as gallic acid equivalents. The total flavonoid concentrations varied from 17.49 to 22.48 mg/g, expressed as quercetin equivalents. The significant linear correlation was confirmed between the values for the total phenolic content and antioxidant activity of plant extracts. Adina cordifolia (Roxb.) can be regarded as promising candidates for natural plant sources of antioxidants with high value.

关键词： Adina cordifolia Antioxidant Activity Flavonoids Total Phenolic Content DPPH

Antioxidant activity of phytosynthesized biomatrix-loaded noble metallic nanoparticles

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Chinese Journal of Chemical Engineering 2018年第5期26卷 1200-1208页

作者： preeti Dauthal Mausumi Mukhopadhyay Department of Chemical Engineering Sardar Vallabhbhai National Institute of Technology Surat 395007 Gujarat India Department of Chemical Engineering Marwadi University Gauridad Rajkot 360003 Gujarat India

Biofabrication of noble monometallic platinum nanoparticles(Pt-NPs) and bimetallic gold–silver nanoparticles(Au Ag-NPs) using aqueous extract of Delonix regia is presented here. Antioxidant activity of biomatrix-loaded metallic nanoparticles is estimated for scavenging of two model radicals i.e., 2,2′-Azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt and 1,1′-Diphenyl-2-picrylhydrazyl. Broad spectral continuum spanning from visible to ultra-violet region(Pt-NPs: 30 min) and broad high intensity absorption peak around at 500 nm(Au Ag-NPs: 10 min) in two different UV–Visible spectra confirmed the biofabrication. Nanoparticles fabricated with distorted spherical shape and crystalline face-centred-cubic geometry. Strong signal around at 2.10 ke V(pure-phase platinum) and typical X-ray peaks observed at 2.20 and 3 ke V suggested, co-existence and alloying interaction of Au and Ag in Au Ag-NPs. ζ potential(-15.2 mV: Pt-NPs and -13.9 mV: Au Ag-NPs) values suggested surface adsorption of polyphenolic compounds to provide stability. Nanoparticles exhibited pronounced antioxidant activity against free radicals through their electron/hydrogen transfer ability.

关键词： Platinum Gold-silver Nanopartides Antioxidant Free radical

Natural products:a rising star for treating primary dysmenorrhea?

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Traditional Medicine Research 2022年第6期7卷 73-82页

作者： Ankita Wal Pranay Wal Divyanshi Gupta Awani Kumar Rai preeti Sharma Nem Kumar jain Department of Pharmacy Pranveer Singh Institute of TechnologyUttar Pradesh 209305India School of Pharmacy ITM University GwaliorMadhya Pradesh 475001India

In the current scenario,dysmenorrhea is a very frequent gynecological condition among *** least one in every four women suffers from severe abdominal cramps,which are referred to as dysmenorrhea or menstrual ***,in this review we compile the data from several reviews and research papers about dysmenorrhea,its pathogenesis,along with all treatment *** was found in a survey that normally women treated these cramps with non-steroidal anti-inflammatory medicines or oral contraceptives,but lately it was found that these medications have a 20%to 25%failure rate as well as unpleasant side ***,in this review,we concluded all the possible treatments,including pharmacological treatment,non-pharmacological treatment,and herbal treatments for *** women are looking for alternatives to conventional treatments,such as the use of herbs,vitamins,minerals,nutritional supplements,analgesics,anti-inflammatory agents,and aromatherapy agents,which can have a significant impact when taken on a regular *** active constituents of these medicinal plants help the body fight cramps and pain associated with menstruation,as well as alleviate these issues in the most calming and effective way possible.

关键词： dysmenorrhea menstrual cramps treatment of dysmenorrhea herbal treatment for menstrual pain

A Cooperative Approach of Frequency Regulation Through Virtual Inertia Control and Enhancement of Low Voltage Ride-through in DFIG-based Wind Farm

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Journal of Modern Power Systems and Clean Energy 2022年第6期10卷 1519-1530页

作者： preeti Verma Seethalekshmi K. Bharti Dwivedi Department of Electrical Engineering Institute of Engineering and TechnologyLucknow 226021Uttar PradeshIndiawhich is a constituent institute of Dr.A.P.J.Abdul Kalam Technical UniversityLucknowUttar Pradesh(U.P.)India IEEE

Doubly-fed induction generator(DFIG)-based wind farms(WFs)are interfaced with power electronic *** interfaces are attributed to the low inertia generated in the WFs under high penetration and that becomes prevalent in a fault ***,transient stability enhancement along with frequency stability in DFIG-based WFs is a major concern in the present *** this paper,a cooperative approach consisting of virtual inertia control(VIC)and a modified grid-side converter(GSC)approach for low voltage ride-through(LVRT)is proposed to achieve fault ride-through(FRT)capabilities as per the grid code requirements(GCRs)while providing frequency support to the grid through a synthetic *** proposed approach provides LVRT and reactive power compensation in the *** participation of the VIC in a rotor-side converter(RSC)provides frequency support to the DFIG-based *** combined approach supports active power compensation and provides sufficient kinetic energy support to the system in a contingency *** studies are carried out in MATLAB/Simulink environment for symmetrical and unsymmetrical *** superiority of the proposed scheme is demonstrated through analysis of the performance of the scheme and that of a series resonance bridge-type fault current limiter(SR-BFCL).

关键词： Virtual inertia controller(VIC) doubly-fed induction generator(DFIG) fault ride-through(FRT)capability wind farm(WF) fault current limiter(FCL)

Non-static plane symmetric perfect fluid solutions and Killing symmetries in f(R,T)gravity

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Communications in Theoretical Physics 2024年第2期76卷 145-150页

作者： preeti Dalal Karanjeet Singh Sachin Kumar Department of Mathematics and Statistics Central University of PunjabBathinda151401PunjabIndia Department of Mathematics Jaypee University of Information TechnologySolan173234Himachal PradeshIndia

In this paper,the non-static solutions for perfect fluid distribution with plane symmetry in f(R,T)gravitational theory are ***,using the Lie symmetries,symmetry reductions are performed for considered vector fields to reduce the number of independent ***,corresponding to each reduction,exact solutions are *** vectors lead to different conserved ***,we figure out the Killing vector fields corresponding to all derived *** derived solutions are further studied and it is observed that all of the obtained spacetimes,at least admit to the minimal symmetry group which consists of δ_(y),δ_(z) and -zδ_(y)+yδ_(z).The obtained metrics,admit to 3,4,6,and 10,Killing vector *** of linear momentum in the direction of y and z,and angular momentum along the x axis is provided by all derived solutions.

关键词： Einstein field equations perfect fluid solutions f(R T)gravity killing symmetries

Finite control set model predictive control of three-port converter for interfacing a PV-battery energy storage system to a three-phase stand-alone AC system

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Clean Energy 2024年第2期8卷 73-84页

作者： Gangashetty A.preeti Anbalagan Karthikeyan Department of Electrical and Electronics Engineering National Institute of Technology KarnatakaSurathkal575025India

This paper proposes a multiport bidirectional non-isolated converter topology that provides advantages in terms of simultaneous multiple operations,single-stage conversion,high power density and reduced power losses due to the lower number of *** proposed multiport converter uses a centralized non-linear controller known as a finite control set model predictive controller to manage the flow of power between different *** deals with the parallel operation of photovoltaic and battery energy storage systems for stand-alone alternating current(AC)*** converter connects the lower voltage battery to the photovoltaic port using a bidirectional buck/boost converter and the photovoltaic port is linked to the stand-alone AC load through a three-phase full-bridge *** leg of the three-phase converter will act as a bidirectional direct current(DC)/DC converter as well as an inverter *** six switches manage the power transfer between all the connected ports of photovoltaic-battery energy storage system linked to the stand-alone AC *** proposed multiport converter is mathematically modelled and controlled by a finite control set model predictive *** system is validated in simulation(1-kW rating)and experimental environment(200-W rating).The hardware prototype is developed in the laboratory and the controller is implemented on the field-programmable gate array *** independent case studies are carried out to validate the efficacy of the *** first scenario is for a change in solar irradiance,while the second scenario is for a change in the output load.

关键词： multiport converter DC/AC converter DC/DC converter finite control set model predictive controller(FCSMPC) PV-BESS three-phase converter

ML-Fresh: Novel Routing Protocol in Opportunistic Networks Using Machine Learning

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Computer Systems Science & Engineering 2022年第2期40卷 703-717页

作者： Puneet Garg Ashutosh Dixit preeti Sethi Department of Computer Engineering J.C.Bose University of Science and TechnologyYMCAFaridabad121006India

Opportunistic Networks(OppNets)is gaining popularity day-by-day due to their various applications in the real-life *** two major reasons for its popularity are its suitability to be established without any requirement of additional infrastructure and the ability to tolerate long delays during data *** Network is also considered as a descendant of Mobile Ad hoc Networks(Manets)and Wireless Sensor Networks(WSNs),therefore,it inherits most of the traits from both mentioned networking *** from its popularity,Opportunistic Networks are also starting to face challenges nowadays to comply with the emerging issues of the large size of data to be communicated and blind forwarding of data among participating nodes in the *** issues lower the overall performance of the *** this thing in mind,ML-Fresh-a novel framework has been proposed in this paper which focuses to overcome the issue of blind forwarding of data by maintaining an optimum path between any pair of participating nodes available in the OppNet using machine learning techniques *** prediction,decision tree prediction,adamic-adar method for complex *** from this,ML-Fresh also uses the history of successful encounters between a pair of communicating nodes for route prediction in the *** results prove that the ML-Fresh outperforms the existing framework of Opportunistic Networks on the grounds of standard Quality-of-Service(QoS)parameters.

关键词： Opportunistic networks artificial intelligence machine learning link prediction routing protocols QoS parameters

Hopf bifurcation and chaos in a Leslie–Gower prey–predator model with discrete delays

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International Journal of Biomathematics 2020年第6期13卷 135-161页

作者： Anuraj Singh preeti Pradeep Malik ABV-Indian Institute of Information Technology and Management Gwalior M.P.India Department of Mathematics University of Petroleum Energy Studies DehradunUttarakhandIndia

In this work,a Leslie–Gower prey-predator model with two discrete delays has been *** positivity,boundedness and persistence of the delayed system have been *** system exhibits the phenomenon of Hopf bifurcation with respect to both *** conditions for occurrence of Hopf bifurcation are obtained for different combinations of *** is shown that delay induces the complexity in the system and brings the periodic oscillations,quasi-periodic oscillations and *** properties of periodic solution have been determined using central manifold and normal form ***,the global stability of the system has been established for different cases of discrete *** numerical computation has also been performed to verify analytical results.

关键词： Discrete delays limit cycle global stability Hopf bifurcation chaotic behavior