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Wet Chemical Synthesis of Entangled Nano-fibrous Conducting Polyaniline(PANI) Mesh: Effect of Heating and Stirring

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Journal of Wuhan University of Technology(Materials Science) 2019年第6期34卷 1463-1469页

作者： Chandrashekhar M.Mahajan Sachin S Sawant Department of Engineering sciences and humanities Vishwakarma Institute of Technology

An effect of heating and stirring in a facile wet chemical route to synthesize entangled nanofibrous mesh of doped polyaniline(PANI) was reported. The structural, morphological, and optical properties of PANI nano-fibers were found to be dependent on synthesis temperature and stirring. The XRD analysis confirms nano PANI formation with 2θ peaks around 15°, 21°, and 25° for(011),(020), and(200) crystal planes, respectively. The average crystallite size varies between 25 nm to 60 nm due to change in synthesis conditions. The SEM analysis reveals the clustered granule formation for PANI sample synthesized at 28 and 60 ℃ under continuous stirring, whereas, unstirred synthesis at 60 ℃ shows entangled nano-fibrous mesh morphology. The TGA study shows better thermal stability for PANI mesh over granular PANI. The FTIR spectra validates the emeraldine salt PANI formation with peaks corresponding to C-H, C-N, N=Q=N, N=B=N, and N-H vibration bands. The UV-Vis analysis shows the major absorbance peaks around λ: 340 nm(π-π* transition of benzenoid ring), and λ: 800 nm(π-π*, polaron-π*, π-polaron transitions). The dense entangled nano-fibrous coating of PANI synthesized at 60 ℃ without stirring shows highest electrical conductivity of 3.79 S·cm^-1.

关键词： polyaniline nano-fibrous mesh optical property electrical conductivity

Band structure characteristics of T-square fractal phononic crystals

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Chinese Physics B 2013年第3期22卷 380-384页

作者：刘晓健凡友华 School of Natural sciences and humanities Shenzhen Graduate School of Harbin Institute of Technology

The T-square fractal two-dimensional phononic crystal model is presented in this article.A comprehensive study is performed for the Bragg scattering and locally resonant fractal phononic *** find that the band structures of the fractal and non-fractal phononic crystals at the same filling ratio are quite different through using the finite element *** fractal design has an important impact on the band structures of the two-dimensional phononic crystals.

关键词： fractal design phononic crystal band gap filling ratio

Stability of LRS Bianchi type-I cosmological models in f(R,T)-gravity

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Research in Astronomy and Astrophysics 2019年第4期19卷 63-76页

作者： Umesh Kumar Sharma Rashid Zia Anirudh Pradhan Aroon Beesham Department of Mathematics Institute of Applied Sciences & Humanities GLA University Department of Mathematical sciences University of Zululand

This paper examines the stability of the transition from the early decelerating stage of the Universe to the recent accelerating stage for the perfect fluid cosmological locally rotationally symmetric(LRS) Bianchi-I model in f(R, T) theory. To determine the solution of field equations, the idea of a timevarying deceleration parameter(DP) which yields a scale factor, for which the Universe attains a phase transition scenario and is consistent with recent cosmological observations, is used. The time-dependent DP yields a scale factor a=exp■, where β and k are respectively arbitrary and integration constants. By using the recent cons_traints(H_0 _= 73.8, and q_0 =-0.54) from Type Ia Supernova(SN Ia) data in combination with Baryonic Acoustic Oscillations(BAO) and Cosmic Microwave Background(CMB) observations(Giostri et al.), we obtain the values of β = 0.0062 and k = 0.000016 for which we have derived a cosmological model from the early decelerated phase to the present accelerating phase. By applying_ other r_ecent constraints(H_0 = 73.8, q_0 =-0.73) from SNe Ia Union data(Cunha), we obtain the values of β = 0.0036 and k = 0.000084 for which we have derived a cosmological model in the accelerating phase only. We have compared both models with experimental data. The stability of the background solution has been examined also for the metric perturbations alongside the properties of future singularities in a Universe ruled by dark energy with phantom type fluid. We demonstrate the presence of a stable fixed point with a condition of state ω <-1 and numerically affirm this is really a late-time attractor in the ghost overwhelmed Universe. Some physical and geometric properties of the model are found and examined.

关键词： LRS Bianchi-I Universe Time-dependent deceleration parameter f(R,T) gravity theory Transit universe

TransientWaves Due to Mechanical Loads in Elasto-Thermo-Diffusive Solids

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Advances in Applied Mathematics and Mechanics 2011年第1期3卷 87-108页

作者： J.N.Sharma N.K.Sharma K.K.Sharma Department of Applied sciences and humanities National Institute of TechnologyHamirpur-177005India

This paper deals with the study of transient waves in a homogeneous isotropic,solid halfspace with a permeating substance in the context of the theory of generalized *** halfspace is assumed to be disturbed due to mechanical loads acting on its *** model comprising of basic governing differential equations and boundary conditions has been solved by employing Laplace transform *** that the second sound effects are short lived,the small time approximations of solution for various physical quantities have been obtained and the results are discussed on the possible wave *** case of continuous and periodic loads acting at the boundary,the displacement is found to be continuous at each wave front while it is discontinuous in case of impulsive *** temperature and concentration fields are found to be discontinuous at all the wave *** displacement,temperature change and concentration deviation due to impulsive,continuous and periodic mechanical loads have also been evaluated in the physical domain at all times by employing numerical inversion technique of integral *** computer simulated numerical results have been presented graphically in respect of displacement,temperature change and concentration deviation for brass.A significant effect of mass diffusion has been observed on the behaviour of mechanical and thermal waves.

关键词： Diffusion Laplace transform small time approximations wave fronts

Modified strip saturated models for two equal collinear cracks with coalesced zones in piezoelectric media

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Applied Mathematics and Mechanics(English Edition) 2019年第8期40卷 1097-1118页

作者： S.SINGH1 K.SHARMA R.R.BHARGAVA Department of sciences and humanities National Institute of Technology Uttarakhand Srinagar 246174India Department of Mathematics Indian Institute of Technology Roorkee Roorkee 247667India

Two equal collinear cracks with coalesced interior electric saturation zones are analytically studied for two-dimensional (2D) arbitrary polarized semipermeable piezo- electric media based on a modified strip saturated model. The strip saturated model is modified here by varying the strip saturated constant electric displacement condition to the polynomially varying electric displacement conditions. Based on the linear, quadratic, and cubic electric displacement conditions on the inner and outer saturated zones, dif- ferent modified strip saturated models are proposed and studied for two equal collinear cracks. With the Stroh formalism and the complex variable technique, these fracture problems are reduced into different types of non-homogeneous Riemann Hilbert problems in unknown generalized complex potential functions. These mathematical problems are then solved with the Riemann-Hilbert approach to obtain the stress and electric displace- ment components at any point of the domain. The explicit expressions for the outer saturated zone length, the crack opening potential (COP), the crack opening displace- ment (COD), and the local intensity factors (LIFs) are derived. A numerical study is presented for the modified strip saturated model in 2D arbitrary polarized semiperme- able PZT-4 material. The obtained results are compared with those of the strip saturated model, and the effects of the polynomially varying saturation condition on the saturated zones and the applied electrical loadings are presented.

关键词： complex variable coalesced zone piezoelectric Riemann-Hilbert problem strip saturated model

Quantitative genetic analysis of chlorophyll a fluorescence parameters in maize in the field environments

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Journal of Integrative Plant Biology 2014年第7期56卷 695-708页

作者： Domagoj ?imi? Hrvoje Lepedu? Vlatka Jurkovi? Jasenka Antunovi? Vera Cesar Agricultural institute Osijek Faculty of humanities and Social sciences Department of Biology Josip Juraj Strossmayer University of Osijek

Chlorophyl fluorescence transient from initial to maximum fluorescence （“P”step） throughout two intermedi-ate steps （“J”and“I”）（JIP-test） is considered a reliable early quantitative indicator of stress in plants. The JIP-test is particularly useful for crop plants when applied in variable field environments. The aim of the present study was to conduct a quantitative trait loci （QTL） analysis for nine JIP-test parameters in maize during flowering in four field environ-ments differing in weather conditions. QTL analysis and identification of putative candidate genes might help to explain the genetic relationship between photosynthesis and different field scenarios in maize plants. The JIP-test param-eters were analyzed in the intermated B73 ？ Mo17 （IBM） maize population of 205 recombinant inbred lines. A set of 2,178 molecular markers across the whole maize genome was used for QTL analysis revealing 10 significant QTLs for seven JIP-test parameters, of which five were co-localized when combined＆amp;nbsp;over the four environments indicating polygenic inheritance and pleiotropy. Our results demonstrate that QTL analysis of chlorophyl fluorescence parameters was capable of detecting one pleiotropic locus on chromosome 7, coinciding with the gene gst23 that may be associated with efficient photosynthe-sis under different field scenarios.

关键词： Chlorophyll a fluorescence parameters field conditions intermated B73× Mo17 recombinant inbred lines JIP-test maize (Zeamays L.) quantitative trait loci

Vibrational Spectra of Distorted Structure Molecules by Using Lie Algebraic Techniques： an Application to Copper and Magnesium Octaethyl Porphyrin

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Chinese Physics Letters 2010年第10期27卷 80-83页

作者： Srinivasa Rao Karumuri School of sciences and humanities Sri Viveka Institute of Technology (SVIT) Madalavari Gudem Nunna Krihna District-521212 India

Using a U （2） algebraic model the fundamental stretching vibrations of copper octaethyl porphyrin and magnesium octaethyl porphyrin are calculated for 24 vibrational bands. The locality parameter ξ confirms the highly local behavior of the stretching modes of these porphyrin molecules. The model Hamiltonian so constructed appears to describe the vibrational energy levels accurately.

关键词： VIBRATIONAL spectra NUCLEAR structure LIE algebras COPPER compounds PORPHYRINS MOLECULAR models

Complex variable approach in studying modified polarization saturation model in two-dimensional semipermeable piezoelectric media

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Applied Mathematics and Mechanics(English Edition) 2017年第11期38卷 1517-1532页

作者： S. SINGH K. SHARMA R. R. BHARGAVA Department of sciences and humanities National Institute of Technology UttarakhandSrinagar(Garhwal)246174India Department of Mathematics Indian Institute of Technology RoorkeeRoorkee 247667India

A modified polarization saturation model is proposed and addressed math- ematically using a complex variable approach in two-dimensional （2D） semipermeable piezoelectric media. In this model, an existing polarization saturation （PS） model in 2D piezoelectric media is modified by considering a linearly varying saturated normal electric displacement load in place of a constant normal electric displacement load, applied on a saturated electric zone. A centre cracked infinite 2D piezoelectric domain subject to an arbitrary poling direction and in-plane electromechanical loadings is considered for the analytical and numerical studies. Here, the problem is mathematically modeled as a non-homogeneous Riemann-Hilbert problem in terms of unknown complex potential functions representing electric displacement and stress components. Having solved the Hilbert problem, the solutions to the saturated zone length, the crack opening displace- ment （COD）, the crack opening potential （COP）, and the local stress intensity factors （SIFs） are obtained in explicit forms. A numerical study is also presented for the proposed modified model, showing the effects of the saturation condition on the applied electrical loading, the saturation zone length, and the COP. The results of fracture parameters obtained from the proposed model are compared with the existing PS model subject to electrical loading, crack face conditions, and polarization angles.

关键词： complex variable fracture parameter local stress intensity factor (SIF),piezoelectric polarization saturation (PS) model

AIdeal:Sentience and Ideology

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Journal of Social Computing 2023年第4期4卷 275-325页

作者： Daniel Estrada the Department of humanities and Social sciences New Jersey Institute of TechnologyNewarkNJ 07102USA

This paper addresses a set of ideological tensions involving the classification of agential kinds,which I see as the methodological and conceptual core of the sentience ***,I consider ideals involved in the classification of biological and artifactual kinds,and ideals related to agency,identity,and *** ideals frame the background against which sentience in Artificial Intelligence(AI)is theorized and debated,a framework I call the *** make this framework explicit,I review the historical discourse on sentience as it appears in ancient,early modern,and the 20th century philosophy,paying special attention to how these ideals are projected onto artificial agents.I argue that tensions among these ideals create conditions where artificial sentience is both necessary and impossible,resulting in a crisis of *** past this crisis does not require a satisfying resolution among competing ideals,but instead requires a shift in focus to the material conditions and actual practices in which these ideals *** Charles Mills,I sketch a nonideal approach to AI and artificial sentience that seeks to loosen the grip of ideology on the ***,I propose a notion of participation that deflates the sentience discourse in AI and shifts focus to the material conditions in which sociotechnical networks operate.

关键词： sentience agency artifacts artificial intelligence ideology nonideal theory natural kinds participation