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Petroleum Science 2019年第2期16卷 298-317页

作者： m.Kumar m.S.Barak m.kumari Department of mathematics B R Ambedkar Govt. College Department of mathematics Indira Gandhi University

Phenomena of reflection and refraction of plane harmonic waves at a plane interface between an elastic solid and doubleporosity dual-permeability material are investigated. The elastic solid behaves non-dissipatively, while double-porosity dual-permeability materials behave dissipatively to wave propagation due to the presence of viscosity in pore fluids. All the waves(i.e., incident and reflected) in an elastic medium are considered as homogeneous(i.e., having the same directions of propagation and attenuation), while all the refracted waves in double-porosity dual-permeability materials are inhomogeneous(i.e., having different directions of propagation and attenuation). The coefficients of reflection and refraction for a given incident wave are obtained as a non-singular system of linear equations. The energy shares of reflected and refracted waves are obtained in the form of an energy matrix. A numerical example is considered to calculate the partition of incident energy among various reflected and refracted waves. The effect of incident direction on the partition of the incident energy is analyzed with a change in wave frequency, wave-induced fluid-flow, pore-fluid viscosity and double-porosity *** has been confirmed from numerical interpretation that during the reflection/refraction process, conservation of incident energy is obtained at each angle of incidence.

关键词： Plane harmonic wave Double-porosity dual-permeability Reflection/refraction coefficients Energy share Elastic solid

Effect of various physical properties on the reflection coefficients of inhomogeneous waves at the stress-free surface of partially saturated soils induced by obliquely incident fast P-wave

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Journal of Ocean Engineering and Science 2022年第3期7卷 225-236页

作者： m.kumari m.S.Barak A.Singh m.Kumar Department of mathematics M P College for WomenMandi Dabwali125104SirsaHaryanaIndia Department of mathematics Indira Gandhi University MeerpurRewari122503HaryanaIndia Department of mathematics Dr.B R Ambedkar Govt.CollegeDabwali125104SirsaHaryanaIndia

Ghasemzadeh and Abounouri[1]developed a mathematical model of partially saturated soils that is solved using the potential method,which decomposes elastodynamics equations into two standard wave equations,a scalar wave equation for scalar potential and a vector wave equation for vector *** such a medium,four waves exist three longitudinal and one *** fluid phase tortuous path is taken into account in this *** inertial coupling between solid and fluid particles is ***,both open-pore and sealed-pore boundaries are explored to investigate the reflection phenomenon at the surface of partially saturated *** both boundaries,the reflection coefficients of inhomogeneous waves at a partially saturated soil surface are found as a non-singular set of linear *** waves(both reflected and incident)in partially saturated soils are pronounced as inhomogeneous due to viscosity in pore fluids(i.e.,distinct directions of attenuation and propagation).The energy shares of reflected waves are determined using an energy matrix.A numerical example is used to determine the reflection coefficients and the distribution of incident energy among the various reflected *** effect of different physical features on reflection coefficients and incident energy partitioning is illustrated *** conservation of incident energy at the surface of partially saturated soils is mathematically confirmed at all angles of incidence.

关键词： Plane harmonic wave Inhomogeneous Partially saturated soils Reflection coefficients Energy shares

利用常规气象观测数据进行环境空气质量分析的模型研究

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环境科学技术 1990年第2期3卷 39-47,38页

作者： m.kumari O.P.Sharma 邓峰

多箱模型可用于对面源排放的空气污染扩散进行长距离空气质量分析。本研究使多箱模型的输入参数更加实际且易于采用。在对流盛行条件下,作者详尽讨沦了如何确定地面源排放的扩散模型。常规气象观测已用于计算地表感热通量、摩擦速度和... 详细信息

多箱模型可用于对面源排放的空气污染扩散进行长距离空气质量分析。本研究使多箱模型的输入参数更加实际且易于采用。在对流盛行条件下,作者详尽讨沦了如何确定地面源排放的扩散模型。常规气象观测已用于计算地表感热通量、摩擦速度和混合层厚度。辐射模型提供了对地面感热通量的估计。根据相似理论,作者提出了一个用于估计摩擦速度的迭代过程,其通过地表热通量表达式,将辐射计算与行星边界层的近地层联系了起来。主要参数——风速和涡动扩散率廓线已经求得并用于得出小时平均浓度模式。这一种研究很容易用于以观测到的气象参数来研究地面源的污染扩散。

关键词：气象观测数据环境空气质量模型

Systematic study of the product((E(2_2^+)/E(2_1^+)) * B(E2)↑) through the asymmetric rotor model

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Chinese Physics C 2016年第9期40卷 58-62页

作者： Parveen kumari H.m.mittal Dr.B.R.Ambedkar National Institute of Technology

A systematic study of the product（（E（22^＋）/E（21^＋））＊B（E2）↑） is carried out in the major shell space Z=50-82,N=82-126 within the framework of the asymmetric rotor model where the asymmetry parameter γ0reflects change in the nuclear structure.A systematic study of the product（（E（2^＋）/E（2^＋））＊B（E2）↑） with neutron number N is also *** product（（E（22^＋）/E（21^＋））＊B（E2）↑） provides a direct correlation with the asymmetry parameter γ*** effect of subshells is visible in Ba-Gd nuclei with N 〉 82,but not in Hf-Pt nuclei with N 〉 *** study,for the first time,the dependency of the product（（E（22^＋）/E（21^＋））＊B（E2）↑） on the asymmetry parameterγ0.

关键词： nuclear structure asymmetric rotor model reduced electric quadrupole transition probability

Synthesis, spectroscopic characterization, and thermal decomposition kinetics of some lanthanide(III) nitrate complexes of 2-(N-o-hydroxyacetophenone) amino-3-carboxyethyl-4,5,6,7-tetrahydrobenzo[b]thiophene

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Journal of Rare Earths 2008年第4期26卷 463-468页

作者： K. mohanan m. Thankamony B. Sindhu kumari Department of Chemistry University of Kerala Kariavattom Campus Trivandrum-695 581. Kerala India

Complexes of La（Ⅲ）, Ce（Ⅲ）, Pr（Ⅲ）, Nd（Ⅲ）, Sm（Ⅲ）, Eu（Ⅲ）, Gd（Ⅲ）, Dy（Ⅲ）, Yb（Ⅲ）, and Lu0ID with 2-（N-o- hydroxyacetophenone）amino-3-carboxyethyl-4,5,6,7-tetrahydrobenzo[b]thiophene （HAAT） formed by the condensation of o-hydroxyacetophenone and 2-amino-3-carboxyethyl-4,5,6,7-tetrahydrobenzo[b]thiophene were synthesized and characterized on the basis of elemental analyses, molar conductance measurements, magnetic susceptibility data, UV-Visible, IR, and NmR spectral studies. The spectral data revealed that the ligand acted as a neutral tridentate coordinating to the metal ion through ONO donor sequence. A coordination number nine was proposed for the complexes. Thermal decomposition studies of the ligand and lanthanum（Ⅲ） complex were carried out and kinetic parameters were calculated using Coats-Redfem equation. The decomposition reactions followed random nucleation mechanism with one nucleus on each particle.

关键词： lanthanides o-hydroxyacetophenone molar conductance magnetic susceptibility thermal study rare earths

A new green approach for the synthesis of 12-aryl-8,9,10,12-tetrahydrobenzo[a]xanthene-11-one derivatives using task specific acidic ionic liquid[NmP]H_2PO_4

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Chinese Chemical Letters 2014年第10期25卷 1336-1340页

作者： Harjinder Singh Sudesh kumari Jitender m.Khurana Department of Chemistry University of Delhi

12-Aryl-8,9,10,12-tetrahydrobenzo[a]xanthene-11-one derivatives were synthesized by a convenient and environmentally benign procedure involving multicomponent condensation reactions of substituted aromatic aldehydes with 2,7-dihydroxynaphthalene/2-naphthols/2,6-dihydroxynaphthlene and cyclic 1,3-dicarbonyl compounds in task specific acidic ionic liquid[NmP]HPOat 80 ℃.This protocol has proved to be efficient in terms of good yields,operational simplicity,easy workup,recyclability of reaction medium/catalyst,and short reaction time.

关键词： Benzo[a]xanthenes Ionic liquids multicomponent reactions Green synthesis

Green mediated synthesis of lanthanum doped zinc oxide:Study of its structural,optical and latent fingerprint application

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Journal of Rare Earths 2020年第12期38卷 1281-1287页

作者： H.N.Shivananjaiah K.Sailaja kumari m.S.Geetha Government Science College Nrupatunga RoadBangalore560001India Base Educational Services BasavanagudiBangalore560004India

The present paper summarises the synthesis of La3+doped zinc oxide nanoparticles using Aloe vera gel by solution combustion method and the characterization using a powder X-ray diffractometer(PXRD),a transmission electron microscope(TEm),an X-ray photometric spectrometer(XPS),a Raman spectrometer and their applications in optical devices and latent *** pattern confirms the crystallite size of La3+doped ZnO varies from 13 to 20 *** size varies inversely with doping *** properties are found to be the maximum for 2 mol% doping *** spectra extends the use of ZnO:La3+nanoparticles in blue green *** nanoparticles also have superior property as a fluorescent labels in fingerprints.

关键词： Green synthesis Nanostructures Photoluminescence Latent fingerprinting Rare earths

Scenario of solar energy and policies in India

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Clean Energy 2024年第5期8卷 117-128页

作者： Sathish Kumar m Prity kumari Y.A.Lad Sherin maria Teaching Assistant Symbiosis Institute of Business ManagementSymbiosis International(Deemed)UniversityNagpur440008MaharashtraIndia Assistant Professor and Head Department of Basic ScienceCollege of HorticultureAnand Agricultural UniversityAnand388110GujaratIndia Associate Professor&Head Department of HRD&PMInternational Agribusiness Management InstituteAnand Agricultural UniversityAnand388110GujaratIndia Research Assistant International Maize and Wheat Improvement Center(CIMMYT)HyderabadTelanganaIndia

Solar power is energy from the Sun that is converted into thermal or electrical ***,the USA,and India have the world’s richest solar energy *** receives solar radiation with an average intensity of 200 mW/km^(2) and 250–300 sunny days a *** solar radiation in India varies from 4 to 7 kWh/m^(2)/day,with 2300–3200 sunshine hours yearly,depending on the *** Solar Park,Jodhpur,India,is the world’s largest solar plant,with 2.25 GW of installed *** energy is the best alternative elec-tricity source used explicitly in the agricultural *** the farming sector,the consumption of solar energy has been *** major issues were the installation costs,low availability of technicians,and poor quality of *** focus on skill development equips the workforce to drive innovation,efficiency,and sustained growth in the renewable-energy *** the support of inter-national collaboration and a skilled workforce,India’s progress in solar energy development is a boon for the industry.

关键词： solar energy benefits policies challenges achievements

Screening of Antioxidant Potential of Selected Barks of Indian medicinal Plants by multiple in vitro Assays

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Biomedical and Environmental Sciences 2008年第1期21卷 24-29页

作者： ARCHANA kumari POONAm KAKKAR Herbal Research Section Industrial Toxicology Research Centre P. O. Box-80 M. G. Marg Lucknow-226001 India

Objective To evaluate the antioxidant potential in herbal extract barks of five therapeutically important medicinal plants native to India, i.e. Crataeva nurvala Buch.-Ham., Buchanania lanzan Spreng., Aegle marmelos Corr., Dalbergia sissoo Roxb. ex DC., and Cedrela toona Roxb. methods Standardized aqueous alcoholic extracts from the selected barks having different target radicals, such as superoxide radical, nitric oxide, ABTS radical, and peroxidative decomposition of phospholipids, were prepared and screened by multiple in vitro assays. These extracts were also tested for total phenolic and tannin content and correlated with antioxidant capacity. Results Total phenolic and tannin contents were found to be the highest in C. nurvala （195 GAE mg/g and 218.3 mg/g CE）. SOD mimetic activity was found to be the highest in Crataeva nurvula, although all barks showed activity more than IO3 units/mg extract. Lipid peroxidation inhibitory potential was found to be the highest in Crataeva nurvala （83.4% inhibition of mDA formation/10 μg extract）, and also showed a comparatively high NO quenching capacity （45.5% per 10 μg extract）. The highest NO quenching potential was found in Aegle marmelos （47.3% per 10 μg extract）. Cedrela toona showed the lowest LPO inhibitory potential and NO quenching capacity （50.5% and 30.5%, respectively）. Buchanania lanzan, a medicinal plant extensively used for inflammatory disorders and Dalbergia sissoo also showed 72.5% and 69.1% LPO inhibitory potential/10 μg extract. Trolox equivalent antioxidant capacity ranged from 0.24 to 0.39 mmol/L TEAC/mg extract, indicating that all the barks tested had ABTS^＋ radical quenching capacity. Conclusion Bark of Crataeva nurvula has the highest antioxidant capacity and a positive correlation between antioxidant activity and their plendic content was found.

关键词： Superoxide dismutase Lipid peroxidation Nitric oxide quenching medicinal plant extracts Reactive oxygen species Antioxidants

Wave-induced flow of pore fluid in a cracked porous solid containing penny-shaped inclusions

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Petroleum Science 2021年第5期18卷 1390-1408页

作者： manjeet kumari Virender manjeet Kumar Dept.of mathematics M P College for WomenMandi Dabwali125104India Dept.of mathematics Ramjas CollegeUniversity of DelhiDelhi110007India Dept.of mathematics Dr.B R Ambedkar Govt.CollegeMandi Dabwali125104India

An aim of current study is to analyze the contribution of reflected longitudinal waves to wave-induced fluid flow(WIFF) in the cracked porous ***,we investigate the time harmonic plane waves in cracked porous solid by employing the mathematical model proposed by Zhang et al.(2019).The solution is obtained in form of the Christoffel *** solution of the Christoffel equations indicates that there exist four(three dilatational and one shear) *** waves are attenuated in nature due to their complex and frequency-dependent *** reflection coefficients are calculated at the sealed pore stress-free surface of cracked porous solid for the incidence of P1 and SV *** is found that three longitudinal waves contribute to WIFF and the contribution of these waves to the induced fluid in the cracked porous solid is analyzed using the reflection coefficients of these longitudinal *** analytically show that the fluid flow induced by these longitudinal waves is linked directly to their respective reflection ***,a specific numerical example is considered to discuss and to depict the impact of various parameters on the characteristics of propagation like phase velocity/attenuation,reflection coefficients and WIFF of longitudinal waves.

关键词： Cracked porous solid Penny-shaped inclusions Longitudinal waves Phase velocity Attenuation Reflection coefficients