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Hydrological impacts of afforestation-A review of research in India

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Journal of Forestry Research 2014年第1期25卷 37-42页

作者： b.Venkatesh N.Lakshman b.k.Purandara Regional Centre National Institute of Hydrology Department of Applied Mechanics National Institute of Technology Karnataka

We review the current status of experimental studies in India to understand the linkages between afforestation and hydrology. This discipline deals with the use and management of water, social awareness of environmental problems, and ecosystem limitations on provision of watershed services by river basins in the mountain regions of India. Our review begins with examination of experimental works in tropical countries and proceeds to discussion of initiatives of Indian research institutes and Government organizations towards establishing experimental watersheds to understand the impacts of land cover changes on hydrologic regimes in the Indian sub-continent. This is followed by the review of the experimental work carried out by various authors to assess the impact of land cover changes on major water balance components such as, runoff, groundwater, evapotranspiration and sediment yield. The spatial scales of these experiments have been limited to small watersheds or field plots. This paper also describes impacts of human interventions （such as planta- tions of exotic forest species to restore degraded landscapes） on the water balance components in diverse hydro-geo-environmental conditions in the Indian sub-continent. We focus on identifying the research areas which require immediate attention to develop tools to assist planners and policy makers in assessing and managing the water resources in these complex environments. The review is largely based on research results reported during the last 20 to 30 years.

关键词： afforestation Western Ghats experimental watersheds land-use/cover changes humid tropics

Nuclear structure and decay modes of Ra isotopes within an axially deformed relativistic mean field model

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Chinese Physics C 2018年第8期42卷 121-129页

作者： Rashmirekha Swain S.k.Patra b.b.Sahu School of Applied Sciences KIIT Deemed to be UniversityBhubaneswar-751024OdishaIndia Institute of Physics Bhubaneswar-751005India

We examine the structural properties and half-life decay of Ra isotopes within the axially deformed Relativistic Mean-Field（RMF）theory with NL3 force *** work out the binding energy（bE）,RMS radii,two-neutron separation energies（S（2n））,and some other *** results are in good agreement with the finite-range droplet model（FRDM）and experimental *** the possibility of neutron magic number,theα-decay and cluster decay half-lives of Ra isotopes are calculated systematically using the Q-values obtained from the RMF *** decay half-life calculations are carried out by taking three different empirical *** calculated decay half-lives are found to be highly sensitive to the choice of *** shell or sub-shell closures are found at daughter nuclei with N=128 and N=126 when alpha and 8be,12C,18O respectively are emitted from Ra *** the cluster radioactivity is affected by the shell closure of parent and daughter,a long half-life indicates the stability of the parent,and a small parent half-life indicates that the shell stability of the daughter against decay.

关键词： relativistic mean field nuclear bulk properties alpha and cluster decay half-life

A novel microscale selective laser sintering(μ-SLS)process for the fabrication of microelectronic parts

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Microsystems & Nanoengineering 2019年第1期5卷 1-14页

作者： Nilabh k.roy Dipankar behera Obehi G.Dibua Chee S.Foong Michael A.Cullinan Department of Mechanical Engineering The University of Texas at Austin204 E.Dean Keeton StAustinTX 78712USA NXP Semiconductors 6501W William Cannon DrAustinTX 78735US

One of the biggest challenges in microscale additive manufacturing is the production of three-dimensional,microscale metal parts with a high enough throughput to be relevant for commercial *** paper presents a new microscale additive manufacturing process called microscale selective laser sintering(μ-SLS)that can produce true 3D metal parts with sub-5μm resolution and a throughput of greater than 60mm^(3)/***μ-SLS,a layer of metal nanoparticle ink is first coated onto a substrate using a slot die coating *** ink is then dried to produce a uniform nanoparticle ***,the substrate is precisely positioned under an optical subsystem using a set of coarse and fine nanopositioning *** the optical subsystem,laser light that has been patterned using a digital micromirror array is used to heat and sinter the nanoparticles into the desired *** set of steps is then repeated to build up each layer of the 3D part in theμ-SLS ***,this new technology offers the potential to overcome many of the current limitations in microscale additive manufacturing of metals and become an important process in microelectronics packaging applications.

关键词： coating process additive

Organic photovoltaic cells with copper(Ⅱ) tetra-methyl substituted phthalocyanine

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Chinese Physics b 2013年第12期22卷 533-536页

作者：许宗祥 roy V. A. L Department of Chemistry South University of Science and Technology of China Center of Super Diamond and Advanced Films (COSDAF) Department of Physics and Materials Science City University of Hong Kong

Efficient heterojunction organic photovoltaic （OPV） cells are fabricated based on copper tetra-methyl phthalocyanine （CuMePc） as donor and fullerene （C60） as acceptor. The power conversion efficiency of CuMePc/C60 OPV cell （2.52%） is increased by 88% compared with that of the non-peripheral substituted copper phthalocyanine （CuPc）/C60 OPV cell （1.34%）. The introduction of methyl substituent leads to stronger π–π interaction of CuMePc （～ 3.5 ？） than that of CuPc （～ 3.8 ？）. The efficiency improvement is attributed to the enhanced carrier mobility of CuMePc thin film （1.1×10-3 cm2/V·s） and better film morphology by introducing methyl groups into the periphery of CuPc molecule.

关键词： organic photovoltaic cell copper (Ⅱ) tetra-methyl substituted phthalocyanine π–π stacking GIXRD

A Numerical Analysis of Turbulent Compressible Radial Channel Flow with Particular Reference to Pneumatic Controllers

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Journal of Thermal Science 2004年第1期13卷 24-29页

作者： Gilles roy Dinh Vo-Ngoc Vadim bravine Faculty of Engineering Université de MonctonMonctonNBCanadaE1A 3E9Faculty of EngineeringUniversité de MonctonMonctonNBCanadaE1A 3E9Faculty of EngineeringUniversité de MonctonMonctonNBCanadaE1A 3E9

A numerical analysis of turbulent axisymmetric radial compressible channel flow between a nozzle and a flat plate is presented in this paper. In particular, the application of this type of flow situation in pneumatic dimensional control systems is considered. The Spalart-Allmaras one-equation turbulence model is used. The resulting highly coupled PDE system has been solved using the control volume based numerical approach where the power-law scheme was used extensively to compute the diffusive and convective fluxes of momentum. Results show that local Mach numbers can easily achieve and surpass unity for typical industrial configurations. Also, in the case of a standard industrial nozzle geometry, the presence of a toroidal recirculation zone that moves radially outward is clearly identified in most cases. Separated flow areas are of particular concern as it has been shown previously that they can cause nozzle fouling in industrial applications. It has been shown that the size of this region is dependant on feed pressure. Considerable differences between results obtained using the Spalart-Allmaras and standard k- εturbulence models have also been noticed.

关键词： compressible radial flow numerical simulation pneumatic controllers impinging jet with confinement.

Structural and mass transport properties of liquid ytterbium in the temperature range 1123 k–1473 k

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Chinese Physics b 2023年第6期32卷 481-488页

作者： D D Satikunvar N k bhatt b Y Thakore Department of Physics Sardar Patel UniversityVallabh VidyanagarGujarat 388120India Department of Physics Maharaja Krishnakumarsinhji Bhavnagar UniversityBhavnagarGujarat 364001India

We have studied the structural and atomic transport properties of liquid f-shell Yb in the temperature range 1123 k–1473 k. Pair interactions between atoms are derived using a local pseudopotential. The potential parameters are fitted to the phonon dispersion curve at room temperature. The local pseudopotential used in the present study is computationally more efficient with only three parameters, and it is found to be transferable to the liquid phase without changing the *** the various computed properties agree with reported theoretical and experimental findings, the adopted fitting scheme is justified. As a significant outcome of the study, we find that(i) the melting in Yb is governed by the Lindemann's law,(ii)the mass transport mechanism obeys the Arrhenius law,(iii) the role of the three-particle correlation function in deriving the velocity autocorrelation function is small,(iv) the mean-square atomic displacement is more sensitive to the choice of interaction potential than the other bulk properties, and(v) liquid Yb does not show liquid–liquid phase transition within the studied temperature range. Further, due to the good description of the structural and mass transport properties, we propose that Yb remains divalent at reduced density.

关键词： transport properties pseudopotential single-particle dynamics ytterbium

Strange quark mass(ms)dependent model of anisotropic strange quark star

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Chinese Physics C 2023年第9期47卷 145-161页

作者： A.Hakim k.b.Goswami P.k.Chattopadhyay Department of Physics Coochbehar Panchanan BarmaUniversityVivekananda StreetDistrict:Coochbehar736101West BengalIndia

This article presents the configuration of strange quark stars in hydrostatic equilibrium considering the Vaidya-Tikekar metric *** interior of such stars comprises strange quark matter(henceforth SQM),whose equation of state(hencefor orth EoS)is described by the MIT EoS p=1/3(p-4b),where b is the difference between perturbative and non-perturbative *** have included the mass of the strange quark into the EoS and studied its effect on the overall properties of the strange quark star in this *** is observed that the maximum mass reaches its highest value *** have evaluated the range of the maximum mass of the strange quark star by solving the TOV equation for 57.55bble strange quark matter at a zero external pressure condition with respect to *** mass lies within the range of to when b ranges from 57.55 to 91.54MeV/fm^(3)and ms=*** is noted that the maximum mass decreases with an increase *** model is found suitable for describing the mass of pulsars such as PSR J1614-2230 and Vela X-1 and the secondary objects in the GW170817 *** model is also useful in predicting the radius of the recently observed pulsars PSR J0030+0451,PSR J0740+6620,and PSR J0952-0607 and the secondary objects in the GW170817 and GW190814 *** model is found to be stable with respect to all stability criteria of the stellar configurations and is also stable with respect to small perturbations.

关键词： Einstein field equation strange star strange quark mass MIT bag model

Magnesium matrix composite reinforced by nanoparticles-A review

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Journal of Magnesium and Alloys 2021年第1期9卷 57-77页

作者： k.b.Nie X.J.Wang k.k.Deng X.S.Hu k.Wu State key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China

Significant progress has been made in magnesium-based composites during recent decades,especially for the appearance of magnesium matrix composite reinforced by *** nanoparticles added not only exhibit a good strengthening effect,but also maintain the initial toughness of the matrix,effectively balancing the contradiction between the strength and plasticity in the traditional magnesium matrix *** magnesium matrix nanocomposites with excellent mechanical properties have pushed the development of magnesium matrix composites to a new ***,it is very difficult to disperse the nanoparticles in metal melt especially in magnesium melt which is different from other metal melts and dangerous during the cast *** means that the preparation of magnesium matrix nanocomposite is extremely ***,the magnesium matrix nanocomposites possess a distinctive characteristic in deformation behavior,strengthening and toughening mechanism due to their special size effect of ***,this review will focus on the new preparation technologies,deformation behavior,mechanical properties and strengthening and toughening *** potential applications,development trends and future research ideas of magnesium matrix nanocomposite are also prospected.©2020 Published by Elsevier *** behalf of Chongqing University.

关键词： Magnesium matrix nanocomposite Microstructure Mechanical properties Strengthening mechanism

A new four-dimensional chaotic system with first Lyapunov exponent of about 22,hyperbolic curve and circular paraboloid types of equilibria and its switching synchronization by an adaptive global integral sliding mode control

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Chinese Physics b 2018年第4期27卷 214-227页

作者： Jay Prakash Singh binoy krishna roy Zhouchao Wei Department of Electrical Engineering National Institute of Technology Silchar Silchar 788010 India School of Mathematics and Physics China University of Geosciences Wuhan 430074 China

This paper presents a new four-dimensional（4 D） autonomous chaotic system which has first Lyapunov exponent of about 22 and is comparatively larger than many existing three-dimensional（3 D） and 4 D chaotic *** proposed system exhibits hyperbolic curve and circular paraboloid types of *** system has all zero eigenvalues for a particular case of an equilibrium *** system has various dynamical behaviors like hyperchaotic,chaotic,periodic,and *** system also exhibits coexistence of *** behavior of the new system is validated using circuit *** an interesting switching synchronization phenomenon is proposed for the new chaotic *** adaptive global integral sliding mode control is designed for the switching synchronization of the proposed *** the switching synchronization,the synchronization is shown for the switching chaotic,stable,periodic,and hybrid synchronization *** of the controller designed in the paper is compared with an existing controller.

关键词： new hyperchaotic system maximum chaos an infinite number of equilibria hidden attractors switching synchronization global sliding mode control