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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 81-100页

作者： S.SAURABH R.KIRAN d.singh R.VAISH V.S.CHAUHAN School of Mechanical and Materials Engineering Indian Institute of Technology Mandi

Bio-inspired helicoidal composite laminates, inspired by the intricate helical structures found in nature, present a promising frontier for enhancing the mechanical properties of structural designs. Hence, this study provides a comprehensive investigation into the nonlinear free vibration and nonlinear bending behavior of bio-inspired composite plates. The inverse hyperbolic shear deformation theory(IHSdT) of plates is employed to characterize the displacement field, with the incorporation of Green-Lagrange nonlinearity. The problem is modeled using the C0finite element method(FEM), and an in-house code is developed in the MATLAB environment to solve it numerically. Various helicoidal layup configurations including helicoidal recursive(HR), helicoidal exponential(HE), helicoidal semi-circular(HS), linear helicoidal(LH), and Fibonacci helicoidal(FH)with different layup sequences and quasi-isotropic configurations are studied. The model is validated, and parametric studies are conducted. These studies investigate the effects of layup configurations, side-to-thickness ratio, modulus ratios, boundary conditions, and loading conditions at different load amplitudes on the nonlinear vibration and nonlinear bending behaviors of bio-inspired composite plates. The results show that the laminate sequence exerts a substantial impact on both nonlinear natural frequencies and nonlinear bending behaviors. Moreover, this influence varies across different side-to-thickness ratios and boundary conditions of the bio-inspired composite plate.

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Thermal inertia at the MSL and InSight mission sites on Mars

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Earth and Planetary Physics 2022年第1期6卷 18-27页

作者： d.singh S.Uttam Centre of Studies in Resources Engineering Indian Institute of Technology BombayMumbaiIndia Physical Research Laboratory AhmedabadIndia

For planetary surface materials,thermal inertia is the critical property that governs the surface’s daily thermal response and controls diurnal and seasonal surface temperature *** we use the ground measurements made by the MSL Curiosity rover and the InSight lander to determine the thermal inertia of two sites on *** study compares the variation of thermal inertia during and after the Large dust Storm(LdS)of Martian Year(MY)*** determine surface thermal inertia,we derive a simple approximation(using energy balance),which utilizes surface albedo,surface energy flux,and diurnal change in the surface *** average thermal inertia in MY34 is about 39.2%,3.7%,and 3.4%higher than MY35 average thermal inertia for the MSL,InSight(FOV1),and InSight(FOV2),***,the thermal inertia at the InSight(FOV1)is consistently lower by about 20 J·m^(-2)·s^(-1/2)·K^(-1) than the InSight(FOV2)site for all scenarios,indicating variation in the region’s surface *** best-fit surface albedo in MY34(determined using the KRC model)are about 0.08,0.05,and 0.03 higher than MY35 surface albedo for the MSL,InSight(FOV1),and InSight(FOV2),*** increase in both surface albedo and thermal inertia during the LdS indicates that the underlying surface is both more thermally resistant and more reflective than the overlying loose dust.

关键词： Mars Mars surface thermal inertia dust storm Mars climate

Transient photoconductivity in a-(Se80Te20)100-xAgx（0≤x≤4） thin films

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Progress in Natural Science:Materials International 2012年第5期22卷 386-391页

作者： d.singh S.Kumar R.Thangaraj Semiconductors Laboratory Department of PhysicsGuru Nanak Dev UniversityAmritsarPunjab 143005India

Bulk material of(Se80Te20)100-xAgx(0≤x≤4) system was prepared by using a conventional melt quenching *** films of a-(Se80Te20)100-xAgx(0≤x≤4) were deposited by the vacuum evaporation technique at a base pressure of 10-4 mbar onto well-cleaned glass *** dependence of electrical conductivity in the temperature range of 263-333 K has been *** is increase in the value of conductivity with increase in temperature as well as with Ag *** measurements of intensity dependence of photoconductivity show that the photoconductivity increases with intensity as a power law where the power is found to be between 0.5 and 1.0,representing the continuous distribution of *** and decay of photocurrent with time at room temperature at different light intensities for(Se80Te20)98Ag2 thin film samples have also been *** results have been explained on the basis of the dember voltage and interaction between photoexcited holes and the trapped electrons on the surface.

关键词： Chalcogenides Se-Te-Ag system Transient photoconductivity

Nonlinear Coupling of Kinetic Alfvén Waves and Ion Acoustic Waves in the Inner Heliosphere

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Research in Astronomy and Astrophysics 2024年第10期24卷 141-158页

作者： Mani K.Chettri Vivek Shrivastav Rupak Mukherjee Nidhi Gaur R.P.Sharma Hemam d.singh department of Physics Sikkim UniversityGangtokSikkimIndia dAV Public School Sector 14GurugramHaryanaIndia Plasma Simulation Laboratory Department of Energy Science and EngineeringIndian Institute of Technology DelhiDelhiIndia

We study the nonlinear coupling of kinetic Alfvén waves with ion acoustic waves applicable to the Earth’s radiation belt and near-Sun streamer belt solar wind using dynamical equations in the form of modified Zakharov *** simulations show the formation of magnetic field filamentary structures associated with density humps and dips which become turbulent at later times,redistributing the energy to higher *** magnetic power spectra exhibit an inertial range Kolmogorov-like spectral index value of-5/3 for k_(⊥)ρ_(i)d by a steeper dissipation range spectra with indices~-3 for the radiation belt case and~-4 for the nearSun streamer belt solar wind case,here k_(⊥)andρ_(i)represent the wavevector component perpendicular to the background magnetic field and the ion thermal gyroradius,*** quasilinear theory in terms of the Fokker-Planck equation in the region of wavenumber turbulent spectra,we find the particle distribution function flattening in the superthermal tail population which is the signature of particle energization and plasma heating.

关键词： Sun:chromosphere Sun:corona Sun:heliosphere

Organo-petrographic and geochemical characteristics of Gurha lignite deposits,Rajasthan,India:Insights into the palaeovegetation,palaeoenvironment and hydrocarbon source rock potential

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Geoscience Frontiers 2020年第3期11卷 965-988页

作者： Runcie Paul Mathews Bhagwan dsingh Vikram Partap singh Alpana singh Hukam singh Mahesh Shivanna Suryendu dutta Vinod A.Mendhe Rimpy Chetia dST-Birbal Sahni Institute of Palaeosciences Lucknow226007India department of Earth Sciences Indian Institute of Technology BombayMumbai400076India CSIR-Central Institute of Mining and Fuel Research Dhanbad826015India

The sedimentary sequence containing lignite deposits in Gurha quarry of the Bikaner-Nagaur Basin(Rajasthan)has been *** samples from lignite and allied shale horizons were evaluated for petrographical,palynological,palynofacies and organic geochemical inferences,to depict the source flora and to reconstruct the palaeodepositional conditions prevailed during the *** assessment for the hydrocarbon generation potential of these deposits has also been *** results revealed the dominance of huminite macerals and phytoclasts organic matter(OM) indicating the existence of forested vegetation in the vicinity of the depositional site.A relatively high terrigenous/aquatic ratio(TAR) and the carbon preference index(CPI) are also suggesting the contribution of higher plants in the peat ***,the n-alkane distributions,maximizing at n-C17 and n-C29,showed inputs from the algal communities along with the higher plant derived organic *** palynomorphs of the families Onagraceae,Meliaceae,Arecaceae,Rhizophoraceae,Rubiaceae,Ctenolophonaceae, *** with oleanene and ursane types of triterpenoids suggest the contribution from angiosperms source ***,the presence of Araucareaceae and Podocarpaceae pollen grains shows the existence of gymnosperms ***,the presence of tetracyclic diterpanes;demethylated entbeyerane,sandaracopimarane,pimarane,and Kaurane type of compounds confirms the contribution of *** variation in the values of the coefficient of non-equality(H:0.68%-7.56%),the standard deviation(8:0.04%-0.16%) and the coefficient of variability(V:16.10%-46.47%),also shows the heterogeneity in the source organic *** various petrographical indices,palynological entities,and geochemical parameters indicate that the peatforming vegetation was accumulated under a mixed environment and fluctuating hydrological *** interpretation of palynofacies data on APP(Amorphous organ

关键词： Palynofacies Biomarkers Rock-Eval Palaeocene deposits Bikaner-Nagaur Basin

旱地小麦的叶片和芒在不同穗发育时期对籽粒产量的作用

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国外农学（麦类作物） 1992年第6期 35-36页

作者： d.singh 夏晓慧郑全明

旗叶叶片和叶鞘的面积以及旗叶面积的持续期与产量呈正相关.由于不同株高范围的雨养小麦品种在籽粒发育的不同时期叶片及芒的作用至今尚未见报导,所以本试验进行了这方面的研究.

关键词：小麦叶片芒穗籽粒产量

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一种糖的替代品——木糖醇的发酵法生产

四川食品与发酵 1997年第2期23卷 47-52页

作者： P.nigam d.singh 余锟何敢为

木糖醇的应用和重要性木糖醇是一种糖醇,一种在自然界中存在的多醇。由于它天然的可利用特性,通常被应用在一些食品中。是一种比普通多元醇甜的啤味剂,是一种糖源。它极好的应用特性是不需要胰岛素来限定其新陈代谢,因此而被作为临床... 详细信息

木糖醇的应用和重要性木糖醇是一种糖醇,一种在自然界中存在的多醇。由于它天然的可利用特性,通常被应用在一些食品中。是一种比普通多元醇甜的啤味剂,是一种糖源。它极好的应用特性是不需要胰岛素来限定其新陈代谢,因此而被作为临床糖尿病人食品中的蔗糖代用品。而且它的代谢不需要葡萄糖—6—磷酸脱氢酶,对于葡萄糖—6—磷脱氢酶不足的人来说是一种理想的甜味剂。木糖醇最显著的特点是一种抗龋齿甜味剂。

关键词：木糖醇发酵工艺制糖工艺

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糖厂滤泥作为土壤改良剂对钠盐土的改良利用

甘蔗糖业 1982年第9期 50-52页

作者： Y.Rai d.singh 庄学调

比哈尔(Brhar)邦的钠盐土原来的PH约为9.0,电导率约为4.0毫姆欧/厘米,钠饱和度约为17%左右,施用亚硫酸法滤泥200公担/公顷,经过土壤中的反应后,使土壤的PH值降低了0.5单位,电导率达到正常水平,钠饱和度降至7-9%,并增加了有效磷4-5单位,... 详细信息

比哈尔(Brhar)邦的钠盐土原来的PH约为9.0,电导率约为4.0毫姆欧/厘米,钠饱和度约为17%左右,施用亚硫酸法滤泥200公担/公顷,经过土壤中的反应后,使土壤的PH值降低了0.5单位,电导率达到正常水平,钠饱和度降至7-9%,并增加了有效磷4-5单位,结果增加了甘蔗产量。一般说来,施亚硫酸法滤泥200公担/公顷比不施可增产蔗量达263公担/公顷,其经济收益可达3000卢比。因此,可以推荐亚硫酸法糖厂的滤泥不仅能有效地用来改良比哈尔的钠盐土,而且有助于显著地提高甘蔗产量。

关键词：滤泥甘蔗产量制糖工业副产品亚硫酸法糖厂盐土盐渍土

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棉花中三个数量性状的遗传分析

国外作物育种 2003年第1期22卷 57-58页

作者：Ｄ.singh J.P.Yadavendra 谢国禄

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六倍体小麦单体的育种习性

山西小麦通讯 1995年第4期16卷 23-25页

作者： d.singh C.Rajlakshmy 刘新月

***培育的小麦品种中国春全部单体系列和Swaminathan等(1968)育成的印度品种Pb.C591的20个单体系(包括5B),一直保存在印度新德里农业研究所遗传部。这些单体系列被用于遗传和细胞遗传学研究。上述两个单体系列所有单体的育种习性进行了... 详细信息

***培育的小麦品种中国春全部单体系列和Swaminathan等(1968)育成的印度品种Pb.C591的20个单体系(包括5B),一直保存在印度新德里农业研究所遗传部。这些单体系列被用于遗传和细胞遗传学研究。上述两个单体系列所有单体的育种习性进行了为期18年的研究。分析了与品种中国春有关的617株的数据,表明65.6%是单体(20'+1’),36.6%是二体(21'),0.5%是双单体(19'+2’)和0.5%是缺体和三体(20'和20'+1'’或21'+1’)(表1)。同样分析了品种Pb.C591的573株的数据,表明69.6%是单体,29.3%

关键词：小麦六倍体单体系育种习性