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The impact of the environmental factors on the photosynthetic activity of common pine (Pinus sylvestris) in spring and in autumn in the region of Eastern siberia

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Journal of Forestry Research 2018年第6期29卷 1465-1473页

作者： n.E.Korotaeva M.V.Ivanova g.g.suvorova g.b.borovskii siberian Institute of Plant Physiology and biochemistry Siberian Branch of Russian Academy of Sciences

The taiga coniferous forests of the siberian region are the main carbon sinks in the forest ***, the size of the carbon accumulation is determined by the photosynthetic productivity, which is strongly influenced by environmental factors. As a result,an assessment of the relationship between environmental factors and photosynthetic productivity makes it possible to calculate and even predict carbon sinks in coniferous forests at the regional level. However, at various stages of the vegetative period, the force of the connection between environmental conditions and the productivity of photosynthesis may change. In this research, correlations between the photosynthetic activity of scots pine(Pinus sylvestris L.) with the environmental conditions were compared in spring and in autumn. In spring, close positive correlation of the maximum daily net photosynthesis was identified with only one environmental factor. For different years, correlations were for soil temperature(rs= 0.655,p = 0.00315) or available soil water supply(rs= 0.892,p = 0.0068). In autumn within different years, significant correlation was shown with two(temperature of air and soil; rs= 0.789 and 0.896, p = 0.00045 and 0.000006,respectively) and four factors: temperature of air(rs=0.749, p = 0.00129) and soil(rs= 0.84, p = 0.00000),available soil water supply(rs= 0.846, p = 0.00013) and irradiance(rs= 0.826, p = 0.000001). Photosynthetic activity has a weaker connection with changes in environmental factors in the spring, as compared to *** is explained by the multidirectional influence of environmental conditions on photosynthesis in this period and by the necessity of earlier photosynthesis onset, despite the unfavorable conditions. This data may be useful for predicting the flow of carbon in dependence on environmental factors in this region in spring and in autumn.

关键词： Pinus sylvestris L. Eastern siberia Correlations Photosynthetic productivity seasonal changes in environment

Effect on Landau damping rates for a non-Maxwellian distribution function consisting of two electron populations

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Chinese Physics b 2013年第3期22卷 358-365页

作者： M.n.s.Qureshi s.sehar H.A.shah J.b.Cao space science Institute Beihang University Department of Physics Government College University

In many physical situations where a laser or electron beam passes through a dense plasma,hot low-density electron populations can be generated,resulting in a particle distribution function consisting of a dense cold population and a small hot *** of such low-density electron distributions can alter the wave damping rate.A kinetic model is employed to study the Landau damping of Langmuir waves when a small hot electron population is present in the dense cold electron population with non-Maxwellian distribution *** of plasma from Maxwellian distributions significantly alters the damping rates as compared to the Maxwellian *** damping is found for highly nonMaxwellian distributions as well as plasmas with a higher density and hot electron *** of weak damping is also established when the distribution contains broadened flat tops at the low energies or tends to be *** results may be applied in both experimental and space physics regimes.

关键词： Landau damping Langmuir waves two electron populations non-Maxwellian distribution function

MULTIsCALE IssUEs In Dns OF MULTIPHAsE FLOWs

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Acta Mathematica scientia 2010年第2期30卷 551-562页

作者： g.Tryggvason s.Thomas b.Aboulhasanzadeh Worcester Polytechnic Institute

Direct numerical simulations （Dns） have now become a well established tool to examine complex multiphase flows. such flows typically exhibit a large range of scales and it is generally necessary to use different descriptions of the flow depending on the scale that we are examining. Here we discuss multiphase flows from a multiscale perspective. Those include both how Dns are providing insight and understanding for modeling of scales much larger than the ＂dominant scale＂（defined where surface tension, viscous forces or inertia are important）, as well as how Dns are often limited by the need to resolve processes taking place on much smaller scales. both problems can be cast into a language introduced for general classes of multiscale problems and reveal that while the classification may be new, the issues are not.

关键词： direct numerical simulations multiphase flow multiscale problems

Copy-Move Forgery Verification in Images Using Local Feature Extractors and Optimized Classifiers

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big Data Mining and Analytics 2023年第3期6卷 347-360页

作者： s.b.g.Tilak babu Ch srinivasa Rao University College of Engineering JNTU KakinadaKakinada 533003India. Department of ECE JNTUK UCEVizianagaram 535003India.

Passive image forgery detection methods that identify forgeries without prior knowledge have become a key research *** copy-move forgery,the assailant intends to hide a portion of an image by pasting other portions of the same *** detection of such manipulations in images has great demand in legal evidence,forensic investigation,and many other *** paper aims to present copy-move forgery detection algorithms with the help of advanced feature descriptors,such as local ternary pattern,local phase quantization,local gabor binary pattern histogram sequence,Weber local descriptor,and local monotonic pattern,and classifiers such as optimized support vector machine and optimized *** proposed algorithms can classify an image efficiently as either copy-move forged or authenticated,even if the test image is subjected to attacks such as JPEg compression,scaling,rotation,and brightness ***,CAsIA,and MICC datasets and a combination of CoMoFoD and CAsIA datasets images are used to quantify the performance of the proposed *** proposed algorithms are more efficient than state-of-the-art algorithms even though the suspected image is post-processed.

关键词： copy move forgery detection image authentication passive image forgery detection blind forgery detection

Microstructures and Mechanical Properties of Al/Mg Alloy Multilayered Composites Produced by Accumulative Roll bonding

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Journal of Materials science & Technology 2011年第1期27卷 15-21页

作者： H.s. Liu b. Zhang g.P. Zhang shenyang national Laboratory for Materials science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Key Laboratory for Anisotropy and Texture of Materials of Ministry of Education School of Materials & Metallurgy Northeastern University Shenyang 110004 China

Al/Mg alloy multilayered composites were produced successfully at the lower temperature（280 C） by accumulative roll bonding（ARb） processing *** microstructures of Al and Mg alloy layers were characterized by scanning electron microscopy and transmission electron *** hardness and three-point bending tests were conducted to investigate mechanical properties of the *** is found that Vickers hardness,bending strength and stiffness modulus of the Al/Mg alloy multilayered composite increase with increasing the ARb *** and crack propagation along the interface are the two main failure modes of the multilayered composite subjected to bending *** and fracture mechanisms of the composite are analyzed.

关键词： Accumulative roll bonding(ARb) Al/Mg alloy multilayered composite Ultra-fine grains Hardness bending properties

Astrophysical s-factor and reaction rate for 15n(p,γ)16O within the modified potential cluster model

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Chinese Physics C 2024年第4期48卷 130-145页

作者： s.b.Dubovichenko A.s.Tkachenko R.Ya.Kezerashvili n.A.burkova b.M.Yeleusheva Fesenkov Astrophysical Institute 050020 AlmatyKazakhstan new York City College of Technology City University of New YorkBrooklyn11201 New YorkUSA graduate school and University Center City University of New York10016 New YorkUSA al-Farabi Kazakh national University 050040 AlmatyKazakhstan

We study radiative p^(15)n capture on the ground state of ^(16)O at stellar energies within the framework of a modified potential cluster model(MPCM)with forbidden states,including low-lying *** investigation of the ^(15)n(p,γ0)^(16)O reaction includes the consideration of ^(3)s_(1) resonances due to E1 transitions and the contribution of the ^(3)P_(1) scattering wave in the p+^(15)n channel due to the ^(3)P_(1)→^(3)P_(0)M1 *** calculated the astrophysical low-energy s-factor,and the extrapolated s(0)turned out to be within 34.7−40.4 keV·*** important role of the asymptotic constant(AC)for the ^(15)n(p,γ0)16O process with interfering ^(3)s_(1)(312)and ^(3)s_(1)(962)resonances is elucidated.A comparison of our calculation for the s-factor with existing experimental and theoretical data is addressed,and a reasonable agreement is *** reaction rate is calculated and compared with the existing *** has negligible dependence on the variation of AC but shows a strong impact of the interference of ^(3)s_(1)(312)and ^(3)s_(1)(962)resonances in reference to the CnO gamow windows,especially at low *** estimate the contribution of cascade transitions to the reaction rate based on the exclusive experimental data from ***.C.85,065810(2012).The reaction rate enhancement due to the cascade transitions is observed from T_(9)>0.3 and reaches the maximum factor~1.3 at T_(9)=*** present the gamow energy window and a comparison of rates for radiative proton capture reactions ^(12)n(p,γ)^(13)O,^(13)n(p,γ)^(14)O,^(14)n(p,γ)^(15)O,and ^(15)n(p,γ)^(16)O obtained in the framework of the MPCM and provide the temperature windows,prevalence,and significance of each process.

关键词： low and astrophysical energies p^(15)n system thermonuclear reaction rate potential cluster model CnO-cycle

Anchoring of 10-phenylphenothiazine to mesoporous silica materials:A water compatible organic photocatalyst for the degradation of pollutants

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Journal of Materials science & Technology 2022年第8期103卷 134-143页

作者： Daniel gonzález-Muñoz Almudena gómez-Avilés Carmen b.Molina Jorge bedia Carolina belver Jose Alemán silvia Cabrera Organic Chemistry Department Science FacultyUniversidad Autónoma de Madrid28049 MadridSpain Chemical Engineering Department Science FacultyUniversidad Autónoma de Madrid28049 MadridSpain Institute for Advanced Research in Chemical sciences(IAdChem) Universidad Autónoma de Madrid28049 MadridSpain Inorganic Chemistry Department Science FacultyUniversidad Autónoma de Madrid28049 MadridSpain

The application of organic photocatalysts towards the oxidation of pollutants in water is hampered by different limitations such as their insolubility in the ***,we report that the grafting of a photoorganocatalyst into mesoporous silica materials is an ideal approach to obtain effective ***,the photocatalyst 10-phenylphenothiazine(PTH)was easily anchored into three different mesoporous silica-based materials(Msn,MsU-2 and sbA-15)with different particle sizes and pore sizes through an amide bond *** materials were characterized using IR analysis,solid-state X-ray diffraction,porosity and microscopy(sEM and TEM)techniques,showing that PTH is immobilized inside the pores of the materials and its optical properties are maintained after the *** homogeneous PTH was inactive in water media,the three photocatalytic materials were active for the degradation of ***-15-AP-PTH exhibited the highest catalytic performance towards the degradation of acetaminophen and diclofenac under solar irradiation,finding in this manner a new strategy for the decontamination of pollutants.

关键词： Organic semiconductors silica support solar photocatalysis Water treatment Pharmaceuticals

An Investigation of Ionic Flows in a sphere-Plate Electrode gap

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Plasma science and Technology 2013年第10期15卷 1012-1019页

作者： H.Z.ALIsOY s.ALAgOZ g.T.ALIsOY b.b.ALAgOZ Department of Electrical-Electronics Inonu University Department of Physics Inonu University Department of Mathematics Inonu University

This paper presents analyses of ion flow characteristics and ion discharge pulses in a sphere-ground plate electrode system. As a result of variation in electric field intensity in the electrode gap, the ion flows towards electrodes generate non-uniform discharging pulses. Inspection of these pulses provides useful information on ionic stream kinetics, the effective thickness of ion cover around electrodes, and the timing of ion clouds discharge pulse sequences. A finite difference time domain （FDTD） based space-charge motion simulation is used for the numerical analysis of the spatio-temporal development of ionic flows following the first Townsend avalanche, and the simulation results demonstrate expansion of the positive ion flow and compression of the negative ion flow, which results in non-uniform discharge pulse characteristics.

关键词： ion flow FDTD simulation space charge motion

Effect of viscous dissipation and heat source on flow and heat transfer of dusty fluid over unsteady stretching sheet

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Applied Mathematics and Mechanics(English Edition) 2012年第8期33卷 1001-1014页

作者： b.J.gIREEsHA g.s.ROOPA C.s.bAgEWADI Department of studies and Research in Mathematics Kuvempu UniversityShankaraghatta 577451KarnatakaIndia

This paper investigates the problem of hydrodynamic boundary layer flow and heat transfer of a dusty fluid over an unsteady stretching surface. The study considers the effects of frictional heating （viscous dissipation） and internal heat generation or ab- sorption. The basic equations governing the flow and heat transfer are reduced to a set of non-linear ordinary differential equations by applying suitable similarity transformations. The transformed equations are numerically solved by the Runge-Kutta-Fehlberg-45 order method. An analysis is carried out for two different cases of heating processes, namely, variable wall temperature （VWT） and variable heat flux （VHF）. The effects of various physical parameters such as the magnetic parameter, the fluid-particle interaction pa- rameter, the unsteady parameter, the Prandtl number, the Eckert number, the number density of dust particles, and the heat source/sink parameter on velocity and temperature profiles are shown in several plots. The effects of the wall temperature gradient function and the wall temperature function are tabulated and discussed.

关键词： heat transfer boundary layer flow stretching surface dusty fluid viscousdissipation non-uniform heat source numerical solution