检索结果-南通市图书馆

Defence Technology（防务技术） 2023年第1期19卷 1-11页

作者： Elango Natarajan Lídio Inacio Freitas M.s.santhosh Kalaimani Markandan Ammar Abdulaziz Majeed Al-Talib c.s.hassan Faculty of Engineering Technology and Built EnvironmentUCSI UniversityKuala LumpurMalaysia Dili Institute of Technology DiliTimor-Leste selvam composite Materials Research Laboratory Department of Mechanical EngineeringSelvam College of TechnologyTamil NaduIndia

suitability of s-Glass/carbon fiber reinforced polymer composite for submarine hull subjected to hydrostatic pressure has been investigated in the present *** materials have raised concerns owing to their decomposition due to low resistance towards salinity and hence polymer composites have been explored to showcase their mechanical stability to withstand transverse and impact *** this end,the mechanical properties of s-Glass/carbon fiber reinforced polymer composite were experimentally investigated and higher specific strength and stiffness of the composite in comparison to many metallic materials used for submarine hull were *** obtained experimental values were used for the static and dynamic crash analysis of the bow,stern and foil through Finite Element Analysis(FEA);where depth of travel was varied from sea surface level of 0-7000 *** assembly was later developed with the optimum shape and thickness of each *** also report the nonlinear crash analysis upon impact at velocity ranging from 3 to 21 m/***,kinetic energy,acceleration peak and internal energy in struck submarine revealed that travel depth 1750 m and 3500 m is recommendable,more particularly,crash safety factor of the submarine is found to be within limit when submarine encounters crash at 1750 m.

关键词： crash Impact Design submarine Hull Bow stern Foil

Machine learning empowers efficient design of ternary organic solar cells with PM6 donor

在线全文

学校读者我要写书评

暂无评论

Journal of Energy chemistry 2025年第1期100卷 337-347页

作者： Kiran A.Nirmal Tukaram D.Dongale santosh s.sutar Atul c.Khot Tae Geun Kim school of Electrical Engineering Korea University computational Electronics and Nanoscience Research Laboratory School of Nanoscience and Biotechnology Shivaji University Yashwantrao chavan school of Rural Development Shivaji University

Organic solar cells(Oscs) hold great potential as a photovoltaic technology for practical ***, the traditional experimental trial-and-error method for designing and engineering Oscs can be complex, expensive, and time-consuming. Machine learning(ML) techniques enable the proficient extraction of information from datasets, allowing the development of realistic models that are capable of predicting the efficacy of materials with commendable accuracy. The PM6 donor has great potential for high-performance Oscs. However, it is crucial for the rational design of a ternary blend to accurately forecast the power conversion efficiency(PcE) of ternary Oscs(TOscs) based on a PM6 ***, we collected the device parameters of PM6-based TOscs and evaluated the feature importance of their molecule descriptors to develop predictive models. In this study, we used five different ML algorithms for analysis and prediction. For the analysis, the classification and regression tree provided different rules, heuristics, and patterns from the heterogeneous dataset. The random forest algorithm outperforms other prediction ML algorithms in predicting the output performance of PM6-based TOscs. Finally, we validated the ML outcomes by fabricating PM6-based TOscs. Our study presents a rapid strategy for assessing a high PcE while elucidating the substantial influence of diverse descriptors.

关键词： Random forests

A comprehensive investigation on nonlinear vibration and bending characteristics of bio-inspired helicoidal laminated composite structures

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

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.

关键词： Inverse problems

Zero-Absorption Isolines in a 2-Photon 2-Level Atom Model

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

communications in Theoretical Physics 2017年第7期67卷 83-90页

作者： s.s.hassan R.A.Alharbey King Abdulaziz University Faculty of Science Mathematics Department P.O. Box 42696 Jeddah 21551 Kingdom of Saudi Arabia

The c-number atomic Bloch equations modelling the coupling of a 2-photon 2-1evel single atom with a non-resonant （A # O） squeezed vacuum （sV） radiation reservoir show that：（i） The quantum interference （QI） process, of parameter f O, between the 2-photon transition channels causes coupling of the atomic variables （inversion and polarisation）, and, （ii） The sV reservoir parameters （N, M） induce periodic coefficients and hence inhibited oscillatory behaviour in the atomic variables. Perturbative analytical solutions of these non-autonomous B1och equations are derived and used to calculate the absorption spectrum of a weak field probing the system. Of particular, the zero-absorption isolines in the relevant （N, f）- and （A, f ）-planes of the the largest set of points, where absorption is zero, in parameter （M） of the sV reservoir. system parameters are identified computationally. It is found that, the （A, f）-plane depends on the choice of the degree of squeezing

关键词： non-autonomous Bloch equations 2-photon transition quantum interference squeezed vacuumreservoir absorption spectrum

Brain-derived neurotrophic factor signaling in the neuromuscular junction during developmental axonal competition and synapse elimination

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第2期20卷 394-401页

作者： Josep Tomàs Víctor cilleros-Mañé Laia Just-Borràs Marta Balanyà-segura Aleksandra Polishchuk Laura Nadal Marta Tomàs carolina silvera-simón Manel M.santafé Maria A.Lanuza Unitat d’Histologia i Neurobiologia(UHNeurob) Facultat de Medicina i Ciències de la SalutUniversitat Rovira i VirgiliReusSpain

During the development of the nervous system,there is an overproduction of neurons and *** competition between neighboring nerve endings and synapses performing different activity levels leads to their elimination or *** have extensively studied the involvement of the brain-derived neurotrophic factor-Tropomyosin-related kinase B receptor neurotrophic retrograde pathway,at the neuromuscular junction,in the axonal development and synapse elimination process versus the synapse *** purpose of this review is to describe the neurotrophic influence on developmental synapse elimination,in relation to other molecular pathways that we and others have found to regulate this *** particular,we summarize our published results based on transmitter release analysis and axonal counts to show the different involvement of the presynaptic acetylcholine muscarinic autoreceptors,coupled to downstream serine-threonine protein kinases A and c(PKA and PKc)and voltage-gated calcium channels,at different nerve endings in developmental *** dynamic changes that occur simultaneously in several nerve terminals and synapses converge across a postsynaptic site,influence each other,and require careful studies to individualize the mechanisms of specific *** describe an activity-dependent balance(related to the extent of transmitter release)between the presynaptic muscarinic subtypes and the neurotrophin-mediated TrkB/p75NTR pathways that can influence the timing and fate of the competitive interactions between the different axon *** downstream displacement of the PKA/PKc activity ratio to lower values,both in competing nerve terminals and at postsynaptic sites,plays a relevant role in controlling the elimination of supernumerary ***,calcium entry through L-and P/Q-subtypes of voltage-gated calcium channels(both channels are present,together with the N-type channel in developing nerve terminals)contributes to red

关键词： acetylcholine release adenosine receptors axonal competition brain-derived neurotrophic factor calcium channels motor end-plate muscarinic acetylcholine receptors postnatal synapse elimination serine kinases tropomyosin-related kinase receptorB

FORcED OscILLATION OF sEcOND ORDER DIFFERENTIAL EQUATIONs WITH MIXED NONLINEARITIEs

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica scientia 2011年第2期31卷 613-626页

作者： Taher s. hassan Lynn Erbe Allan Peterson Department of Mathematics Faculty of Science Mansoura University Department of Mathematics University of Nebraska-Lincoln

This article is concerned with the oscillation of the forced second order differ- ential equation with mixed nonlinearities（a（t）（x＇（t））γ）＇＋po（t）xγ（go（t））＋n∑t=1pi（t）｜x（gi（t））｜αi sgn x（gi（t））=e（t）,where γ is a quotient of odd positive integers αi〉0,i=1,2 ……n,a,e,and pi ∈ c（[0,∞）R）,a（t）〉0,gi：R→R are positive continuous functions on R with lim gi （t）=∞,i=0,1,……,n. Our results generalize and improve the results in a recent article by sun and Wong[29].

关键词： Oscillation functional differentail equations second order

synthesis of ZnO Nanoparticles onto sepiolite Needles and Determination of Their sensitivity toward Humidity, NO_2 and H_2

在线全文

学校读者我要写书评

暂无评论

Journal of Materials science & Technology 2016年第6期32卷 573-582页

作者： M.hassan Ahmed s.Afify J.M.Tulliani Department of Applied science and Technology Politecnico di Torino

This work investigated the sensitivity toward humidity, NO2 and H2 of ZnO modified sepiolite （si12Mg8O30（OH）4.（H2O）4.8H2O）. To this aim, sepiolite powder was first modified by leaching magnesium ions in HcI then by precipitating nano-sized Zn-based compounds under basic conditions. A subse- quent thermal treatment at 550 ℃ for 1 h was performed. The powders were characterized by X-ray diffraction （XRD）, specific surface area measurements, thermogravimetric and differential thermal anal- ysis and field emission scanning electron microscopy, as well as high resolution transmission electron microscopy. The XRD patterns showed that all leached heat treated samples were made of anhydrous sepiolite and of ZnO. sensors were then obtained by screen printing these materials onto commercial alumina substrates with Pt electrodes. All the investigated compositions were capable of detecting NO2 down to ppm level and 20 ppm H2, at an optimal working temperature of 300°c. These detection limits are in line with the current best results reported in literature.

关键词： clay minerals Gas sensor sensitivity Hydrogen sensor Nitrogen Oxide

Forest structure and woody plant species composition after a wildfire in beech forests in the north of Iran

在线全文

学校读者我要写书评

暂无评论

Journal of Forestry Research 2013年第2期24卷 255-262页

作者： Mohammad Naghi Adel hassan Pourbabaei Ali Omidi Daniel c Dey Facultad de Department of Forestry Natural Resources Faculty University of Guilan Department of Forestry Natural Resources Office UsDA Forest service Northern Research Station 202 Natural Resources Building

Beech （Fagus orientalis Lipsky） forest covers about 565,000 ha of land in Guilan province, north of Iran and forms a major carbon pool. It is an important economic, soil protection and recreation resource. We studied long-term effects of fire on the structure and composition 37 years after fire occurrence in these forests. To do this research, we selected 85 ha burned and 85 ha unburned beech forests）. The results indicated that the fire had not changed the overall uneven-aged structure, but it changed forest composition from pure stands to mixed stands that now include species such as carpinus betulus, Acer cappadocicum and Alnus subcordata. The density of trees and regeneration was significantly increased, while the density of shrubs significantly decreased. The main reasons for increased tree regeneration were attributed to （1） reduction of litter depth, and （2） increase in available light from opening of the canopy and reduction in shrub competition. It is apparent that the forest is on a path to return to its natural state before the fire after 37 years.

关键词： fire structure composition regeneration beech forest Guilan Province

Ultra‑Transparent and Multifunctional IZVO Mesh Electrodes for Next‑Generation Flexible Optoelectronics

在线全文

学校读者我要写书评

暂无评论

Nano-Micro Letters 2025年第1期17卷 293-309页

作者： Kiran A.Nirmal Tukaram D.Dongale Atul c.Khot chenjie Yao Nahyun Kim Tae Geun Kim school of Electrical Engineering Korea UniversityAnam‑ro 145Seongbuk‑guSeoulRepublic of Korea computational Electronics and Nanoscience Research Laboratory School of Nanoscience and BiotechnologyShivaji UniversityKolhapur 416004India

Mechanically durable transparent electrodes are essential for achieving long-term stability in flexible optoelectronic ***,they are crucial for applications in the fields of energy,display,healthcare,and soft *** meshes represent a promising alternative to traditional,brittle,metal oxide conductors due to their high electrical conductivity,optical transparency,and enhanced mechanical *** this paper,we present a simple method for fabricating an ultra-transparent conducting metal oxide mesh electrode using selfcracking-assisted *** this method,we produced an electrode with ultra-transparency(97.39%),high conductance(Rs=21.24Ωsq^(−1)),elevated work function(5.16 eV),and good mechanical *** also evaluated the effectiveness of the fabricated electrodes by integrating them into organic photovoltaics,organic light-emitting diodes,and flexible transparent memristor devices for neuromorphic computing,resulting in exceptional device *** addition,the unique porous structure of the vanadium-doped indium zinc oxide mesh electrodes provided excellent flexibility,rendering them a promising option for application in flexible optoelectronics.

关键词： self-cracking template Vanadium-doped indium zinc oxide mesh Organic solar cells Organic light-emitting diodes Flexible transparent memory

Effects of the phase variation and high-order momentum transfer components of NN amplitude on p-~4He elastic scattering

在线全文

学校读者我要写书评

暂无评论

Nuclear science and Techniques 2018年第1期29卷 65-76页

作者： I.M.A.Tag-Eldin M.M.Taha s.s.A.hassan Nuclear Experimental Physics Department Nuclear Research Center Atomic Energy Authority Mathematics and Theoretical Physics Department Nuclear Research Center Atomic Energy Authority

Elastic scattering differential cross sections for a p- ~4He system are calculated within the framework of optical limit approximation of the Glauber multiple scattering model. Three different ranges for proton energy(E_(lab)), 19〈E_(lab)〈50 Me V, 100≤E_(lab)≤1730 Me V, and 45 ≤E_(lab)≤393 Ge V are considered. It is shown that the Pauli blocking fails to describe the data up to the proton energy, E_(lab)〈100 Me V. For higher proton energies, a qualitative agreement is obtained. The observed elastic scattering differential cross section is nicely reproduced in the whole range of scattering angles in the center of mass system up to Θ_(c.m.)〈200° for 19〈E_(lab) ≤100 Me V when the effect of both the nucleon–nucleon(NN) phase variation parameter γNN and higher-order momentum transfer components(λ_n; n = 1 and 2) of(NN) elastic scattering amplitude is included. In the range of 200 E_(lab) 1730 Me V, introducing λ_n plays a significant role in describing the data up to the momentum transfer, q^2≤1:2(Ge V/c)~***, it is found that considering only the effect of phase variation parameter, cNN, improved the agreement in the region of minima for elastic scattering differential cross section for 45≤E_(lab)≤393 Ge V. The values of cNNand kn as a function of incident proton energies are presented.

关键词： Elastic scattering Optical limit approximation Glauber multiple scattering model