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Effectively modulating spatial vortex four-wave mixing in a diamond atomic system
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作者 巴诺 姜明奇 +4 位作者 费金友 王丹 蒋海林 王磊 王海华 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期473-478,共6页
Due to the spatial characteristics of orbital angular momentum,vortex fields can be applied in the fields of quantum storage and quantum information.We study the realization of spatially modulated vortex fields based ... Due to the spatial characteristics of orbital angular momentum,vortex fields can be applied in the fields of quantum storage and quantum information.We study the realization of spatially modulated vortex fields based on four-wave mixing in a four-level atomic system with a diamond structure.The intensity and spiral phase of the vortex field are effectively transferred to the generated four-wave mixing field.By changing the detuning of the probe field,the phase and intensity of the generated vertex four-wave mixing field can be changed.When the probe field takes a large detuning value,the spatial distribution of the intensity and phase of the vertex four-wave mixing field can be effectively tuned by adjusting the Rabi frequency or detuning value of the coupled field.At the same time,we also provide a detailed explanation based on the dispersion relationship,and the results agree well with our simulation results. 展开更多
关键词 coherent optical effects four-wave mixing orbital angular momentum
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Hybrid Effects on MHD Mixed Convective Boundary Layer Flow through a Sloped Plate in Existence of Nanofluid-Saturated Porous Medium
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作者 Md. Nasir Uddin Abdul Halim Bhuiyan +1 位作者 Zahurul Islam Tahmina Tahrim 《Journal of Applied Mathematics and Physics》 2024年第9期3037-3052,共16页
This study examines the effects of heat, mass, and boundary layer assumptions-based nanoparticle characteristics on the hybrid effects of using MHD in conjunction with mixed convective flow through a sloped vertical p... This study examines the effects of heat, mass, and boundary layer assumptions-based nanoparticle characteristics on the hybrid effects of using MHD in conjunction with mixed convective flow through a sloped vertical pore plate in the existence of medium of porous. Physical characteristics such as thermo-diffusion, injection-suction, and viscous dissipation are taken into consideration, in addition to an equally distributed magnetic force utilized as well in the completely opposite path of the flow. By means of several non-dimensional transformations, the momentum, energy, concentration, and nanoparticle volume fraction equations under investigation are converted in terms of nonlinear boundary layer equations and computationally resolved by utilizing the sixth-order Runge-Kutta strategy in combination together with the iteration of Nachtsheim-Swigert shooting procedure. By contrasting the findings produced for a few particular examples with those found in the published literature, the correctness of the numerical result is verified, and a rather good agreement is found. Utilizing various ranges of pertinent factors, computing findings are determined not only regarding velocity, temperature, and concentration as well as nanoparticle fraction of volume but also concerning with local skin-friction coefficient, local Nusselt and general Sherwood numbers associated with nanoparticle Sherwood number. The findings of the study demonstrate that increasing the fluid suction parameter decreases the velocity and temperature of the flow field in conjunction with concentration and has a variable impact on the nanoparticle fraction of volume, despite an increasing behavior in the local skin friction coefficient and local Nusselt as well as general Sherwood numbers and an increasing behavior in the local nanoparticle Sherwood number. Furthermore, enhancing a Schmidt number leads to a reduction in the local nanoparticle Sherwood number and a rise in the nanoparticle proportion of volume. Along with concentration, it also reduces temperature and velocity. However, it also raises the local Sherwood and Nusselt numbers and reduces the local skin friction coefficient. 展开更多
关键词 Hybrid effects mixed Convection MHD NANOFLUID Viscous Dissipation
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Influence of alkali mixed effect on the mixing enthalpy in 0.75B_2O_3-0.25[xNa_2O-(1-x)K_2O]glass system
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作者 A.Kouyate A.P.Ahoussou +3 位作者 A.Yapi D.Diabate J.Rogez A.Trokourey 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第10期1252-1255,共4页
The mixed alkali effect was investigated in the glass system 0.75B2O3-0.25[xNa2O-(1 -x)K20] through thermodynamic properties. The calorimetric measurements were performed in HF solution calorimetry at 298 K. The mix... The mixed alkali effect was investigated in the glass system 0.75B2O3-0.25[xNa2O-(1 -x)K20] through thermodynamic properties. The calorimetric measurements were performed in HF solution calorimetry at 298 K. The mixing enthalpy values show non-linear behaviour upon substitution of one alkali ion by another. This thermodynamic non-ideality is caused by the slight variations of distance between metallic cations, the macromolecular structure being unchanged. It can be explained, at least qualitatively, using electrolyte theory based on the Coulombic interactions of charged species originally developed by Debye and Hückel. 展开更多
关键词 Alkali mixed effect CALORIMETRY mixing enthalpy Coulombic interactions
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Transverse effects in photorefractive two-wave mixing
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作者 蔡欣 刘劲松 +1 位作者 汪盛烈 刘时雄 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第5期1891-1897,共7页
In a biased photorefractive crystal, the process of two one-dimensional waves mixing, i.e., the dynamical evolution of both pump beam and signal beam, is traced by numerically solving the coupled-wave equation. Direct... In a biased photorefractive crystal, the process of two one-dimensional waves mixing, i.e., the dynamical evolution of both pump beam and signal beam, is traced by numerically solving the coupled-wave equation. Direct simulations show that the propagation and stability of the two beams are completely determined by the system parameters, such as the external bias field, the intensity and the beam waist of the pump beam. By adjusting these parameters, one can control the state of two Gaussian waves mixing. The numerical results are helpful for performing a two-wave mixing experiment. 展开更多
关键词 two-wave mixing transverse effects Gaussian distribution photorefractive crystal
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Effect of Dissolved Cadmium Chloride and Ammonium Chloride Salts on the Enthalpy of Mixing of the Methanol+Benzene System at 303.15 K
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作者 TAMILARASAN Rengasamy ANAND PRABU Arun +1 位作者 KAP JIN Kim DHARMENDIRA KUMAR Mahendradas 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2010年第6期995-999,共5页
The effect of two dissolved inorganic salts,cadmium chloride CdCl2 and ammonium chloride NH4Cl,on the excess enthalpy of mixing(HE) of the binary system methanol + benzene measured at 303.15 K using an iso-thermal dis... The effect of two dissolved inorganic salts,cadmium chloride CdCl2 and ammonium chloride NH4Cl,on the excess enthalpy of mixing(HE) of the binary system methanol + benzene measured at 303.15 K using an iso-thermal displacement calorimeter with vapor space is investigated in the present work. Compared to the salt-free system,a decreasing trend in the endothermicity of HE values is significant with the addition of CdCl2 salt but the decrease in the HE values is insignificantly smaller with the addition of NH4Cl salt. The experimental values of the enthalpy of mixing are fitted into a Redlich-Kister equation and the deviations in the values and the parameters are reported. The importance of the solute-solvent interactions and the solvent-solvent interactions are demonstrated from the increasing excess enthalpy of mixing values in the positive direction with the increase of salt concentration. 展开更多
关键词 salt effect enthalpy of mixing displacement calorimeter methanol-benzene Redlich-Kister equation
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Ba(d)^o-Ba(d)^o Mixing and New Physics Effects in a Top Quark Two-Higgs Doublet Model
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作者 LU Lin-Xia XIAO Zhen-Jun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第6期1099-1105,共7页
We calculate the new physics contributions to the neutral Bd^o and Ba^o meson mass splitting △Md and △Ma induced by the box diagrams involving the charged-Higgs bosons in the top quark two-Higgs doublet model (T2HD... We calculate the new physics contributions to the neutral Bd^o and Ba^o meson mass splitting △Md and △Ma induced by the box diagrams involving the charged-Higgs bosons in the top quark two-Higgs doublet model (T2HDM). Using the precision data, we obtain the bounds on the parameter space of the T2HDM: (a) For fixed MH = 400 GeV and 5= [0°, 60°], the upper bound on tan β is tan β≤ 30 after the inclusion of major theoretical uncertainties; (b) For the case of tan β≤ 20, a light charged Higgs boson with a mass around 300 GeV is allowed; and (c) The bounds on tan β and MH are strongly correlated: a smaller (larger) tan β means a lighter (heavier) charged Higgs boson. 展开更多
关键词 B meson mixing new physics effects two-Higgs-doublet model
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Covalent bonding and J–J mixing effects on the EPR parameters of Er^(3+) ions in GaN crystal
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作者 柴瑞鹏 李隆 +1 位作者 梁良 庞庆 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第7期435-439,共5页
The EPR parameters of trivalent Er(3+) ions doped in hexagonal Ga N crystal have been studied by diagonalizing the 364×364 complete energy matrices. The results indicate that the resonance ground states may be... The EPR parameters of trivalent Er(3+) ions doped in hexagonal Ga N crystal have been studied by diagonalizing the 364×364 complete energy matrices. The results indicate that the resonance ground states may be derived from the Kramers doublet Γ6. The EPR g-factors may be ascribed to the stronger covalent bonding and nephelauxetic effects compared with other rare-earth doped complexes, as a result of the mismatch of ionic radii of the impurity Er(3+)ion and the replaced Ga(3+) ion apart from the intrinsic covalency of host Ga N. Furthermore, the J–J mixing effects on the EPR parameters from the high-lying manifolds have been evaluated. It is found that the dominant J–J mixing contribution is from the manifold 2K(15/2), which accounts for about 2.5%. The next important J–J contribution arises from the crystal–field mixture between the ground state 4I(15/2) and the first excited state4I(13/2), and is usually less than 0.2%. The contributions from the rest states may be ignored. 展开更多
关键词 EPR parameters covalent bonding effect J–J mixing effect rare-earth ion Er3+
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Research of chemical induction unit on mixing effect and chlorine saving
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作者 焦中志 Chen Zhonglin +3 位作者 Li ZuoLiang Xue Zhu  Yuan Xing Li Guibai 《High Technology Letters》 EI CAS 2007年第1期109-112,共4页
Rapid mixing and chlorine saving are two important problems that most drinking water industries are focus on, and this paper adopts chemical induction unit to compare with water jet injector to study what merits chemi... Rapid mixing and chlorine saving are two important problems that most drinking water industries are focus on, and this paper adopts chemical induction unit to compare with water jet injector to study what merits chemical induction unit has. The experiment chose coefficient of variability of chlorine concentration to evaluate the mix effect and used chlorine consumption to compare the two equipments. Distribution reservoir experiments show that chemical induction unit can completely mix chlorine less than 6.2 seconds and water jet injector can not completely mix in 3 minutes. Mixing pool experiments show that chemical induction unit can save chlorine compared with water jet injector, and can save more if more chlorine is consumed. 展开更多
关键词 water jet injector chemical induction unit chlorine water mix effect coefficient ofvariability
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J-mixing Effect of the Crystal-field on the Spectroscopic Characteristics of Rare-earth Doped Laser Crystals
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作者 CHEN Xue-Yuan LUO Zun-Du(Fujian Institute of Research on the Structure of Matter,the Chinese Academy of Sciences, Fuzhou 350002) 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1997年第5期358-364,共7页
By using the re-derived formulae for both line-strength of electricdipole transition and simple J-mixing coefficients within the 4f shell in a rare-earthion, the spectroscopic properties of the luminescent material Eu... By using the re-derived formulae for both line-strength of electricdipole transition and simple J-mixing coefficients within the 4f shell in a rare-earthion, the spectroscopic properties of the luminescent material Eu3+ =Y2O3 and laser crystals Tb3+:=YAlO3 and Nd3+:YVO4, are investigated in detail. On the basis of three fitting Ω parameters and the effective reduced matrix elements, the spectral linestrengths, spontaneous emission probabilities, fluorescent branching ratios and lifetimeare calculated. The better agreement between theoretical results and experimental dataindicates the importance of J-mixing in the spectroscopic study of laser crystals. 展开更多
关键词 J-mixing effect crystal-field analysis rare-earth ion laser crystal
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Effect of Mixed Silage of Alhagi sparsifolia and Medicago sativa at Initial Flowering Stage on Degradation
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作者 蒋慧 应璐 +2 位作者 张秀萍 陈宏伟 马金萍 《Agricultural Science & Technology》 CAS 2010年第11期4-6,113,共4页
[Objective] The influence of mixed silage of A.sparsifolia and M.sativa at initial flowering stage on degradation was studied to provide theoretical basis for production practice.[Method] Using A.sparsifolia and M.sat... [Objective] The influence of mixed silage of A.sparsifolia and M.sativa at initial flowering stage on degradation was studied to provide theoretical basis for production practice.[Method] Using A.sparsifolia and M.sativa at initial flowering stage as materials,the changes of in vitro degradation rate,gas production,pH value,ammoniacal nitrogen(NH3-N)and volatile fatty acid(VFA)content in degradation solution were analyzed by means of artificial rumen technique,and the effect of mixed silage of A.sparsifolia and M.sativa at initial flowering stage on degradation was studied in order to find out suitable mixed silage ratio of A.sparsifolia and M.sativa.[Result] Compared with single M.sativa,NH3-N content in degradation solution was very significantly decreased in the mixed silage of A.sparsifolia and M.sativa,and there was a reduction in gas production,while the content of acetic acid,propionic acid and butyric acid increased significantly;for the treatment of 70% A.sparsifolia and 30% M.sativa,NH3-N content(22.93 mmol/L)and gas production(40.50 ml)was lowest,while degradation rate(32.27%),acetic acid(5.48 mmol/L),propionic acid(2.08 mmol/L),butyric acid(2.52 mmol/L)and their total content(10.08 mmol/L)were highest,so its degradation effect was the best.[Conclusion] The mixed silage of A.sparsifolia and M.sativa at initial flowering stage could improve the utilization efficiency of protein and carbohydrate in M.sativa and the treatment of 70% A.sparsifolia and 30% M.sativa had the best degradation effect. 展开更多
关键词 A.sparsifolia M.sativa mixed silage Degradation effect
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Numerical investigation of variable viscosities and thermal stratification effects on MHD mixed convective heat and mass transfer past a porous wedge in the presence of a chemical reaction 被引量:2
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作者 I. Muhaimin R. Kandasamy Azme B. Khamis 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2009年第11期1353-1364,共12页
An analysis is presented to investigate the effects of variable viscosities and thermal stratification on the MHD mixed convective heat and mass transfer of a viscous, incompressible, and electrically conducting fluid... An analysis is presented to investigate the effects of variable viscosities and thermal stratification on the MHD mixed convective heat and mass transfer of a viscous, incompressible, and electrically conducting fluid past a porous wedge in the presence of a chemical reaction. The wall of the wedge is embedded in a uniform nonDarcian porous medium in order to allow for possible fluid wall suction or injection. The governing boundary layer equations are written into a dimensionless form by similarity transformations. The transformed coupled nonlinear ordinary differential equations are solved numerically with finite difference methods. Numerical calculations up to the thirdorder level of truncation are carried out for different values of dimensionless parameters. The results are presented graphically, and show that the flow field and other quantities of physical interest are significantly influenced by these parameters. The results are compared with those available in literature, and show excellent agreement. 展开更多
关键词 variable viscosity chemical reaction non-Darcy flow mixed convection thermal stratification magnetic effect
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MECHANISM ANALYSIS OF THICKNESS EFFECT ON MIXED MODE Ⅰ/Ⅱ FRACTURE OF LC4-CS ALUMINUM ALLOY 被引量:2
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作者 H.R. Dong W.L. Guo 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2004年第3期255-262,共8页
Mixed mode Ⅰ/Ⅱ fracture erperiments of LC4-CS aluminum alloy were conductedby using tension--shear specimens with thicknesses of 2, 4, 8 and 14mm. Fracturemechanisms of thickness effect on mixed mode Ⅰ/Ⅱ fracture ... Mixed mode Ⅰ/Ⅱ fracture erperiments of LC4-CS aluminum alloy were conductedby using tension--shear specimens with thicknesses of 2, 4, 8 and 14mm. Fracturemechanisms of thickness effect on mixed mode Ⅰ/Ⅱ fracture were first examined fromfracture surface morphology to correlate with the macroscopic fracture behavior andstress state. It is found that specimen thickness has a strong influence on mixed modefracture. As thickness varies from thin to thick the macroscopic fracture surfacesappear the characteristics of plane stress state (2mm, 4mm--thick specimen), three--dimensional stress state (8mm--thick specimens), and plane strain state (14mm--thickspecimens), respectively. The specimens of all kinds of thicknesses are typical of ten-sile type failure under mode Ⅰ loading condition and shear type failure under mode Ⅱloading condition. Two distinct features coexist on the fracture surfaces under mixedmode loading conditions, and the corresponding proportion varies with loading mix-ity. Void--growth processes are the failure mechanism in both predominately tensile-and shears--type fractures. The size and depth of dimples on the fracture surface varygreatly with thickness. Therefore, it is extraordinary necessary to take into accountthe thickness effect when a mixed mode fracture criterion is being established. 展开更多
关键词 LC4-CS aluminum alloy mixed mode Ⅰ/Ⅱ fracture thickness effect macroscopic fracture appearance SEM
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Horizontal gas mixing in rectangular fluidized bed:A novel method for gas dispersion coefficients in various conditions and distributor designs 被引量:2
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作者 Asheesh Nautiyal Chien-Song Chyang +1 位作者 Pin-Wei Li Hsin-Yung Hou 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第7期848-861,共14页
In a rectangular fluidized bed combustor, the tracer gas is injected continuously into the bed from a point source at the center of the distributor plate. In this study, a general governing equation is formulated for ... In a rectangular fluidized bed combustor, the tracer gas is injected continuously into the bed from a point source at the center of the distributor plate. In this study, a general governing equation is formulated for tracer gas dispersion in the bed. An analytical solution is derived to estimate the dispersion coefficients, Dxand Dy, in a horizontal plane. The concentration profiles at different sampling heights with various gas velocities are plotted.Subsequently, to estimate the dispersion coefficients, surface fitting of the obtained analytical solution to the experimental data is performed. The dispersion coefficients obtained from this model are compared with those of a conventional model. Additionally, the effect of walls, bed height and gas injection rate on the dispersion coefficients in a horizontal plane is investigated, and the effect of distributor design on the dispersion coefficients in a horizontal plane is investigated with different tracer positions. It is found that Dxand Dyare nearly equivalent at a lower tracer gas ratio of the injected gas to the total gas flow rate. It is also demonstrated that the effect of bed height on Dxis minor. This model is also able to estimate the dispersion coefficients in the case of a multihorizontal nozzle distributor. 展开更多
关键词 Gas dispersion coefficient Horizontal mixing Wall effect Surface modeling
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Probing neutron–proton effective mass splitting using nuclear stopping and isospin mix in heavy-ion collisions in GeV energy region 被引量:3
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作者 Fan Zhang Jun Su 《Nuclear Science and Techniques》 SCIE CAS CSCD 2020年第8期35-42,共8页
The ramifications of the effective mass splitting on the nuclear stopping and isospin tracer during heavy-ion collisions within the gigaelectron volt energy region are studied using an isospin-dependent quantum molecu... The ramifications of the effective mass splitting on the nuclear stopping and isospin tracer during heavy-ion collisions within the gigaelectron volt energy region are studied using an isospin-dependent quantum molecular dynamics model.Three isotope probes,i.e.,a proton,deuteron,and triton,are used to calculate the nuclear stopping.Compared to the mn*>mp*case,the mn*<mp*parameter results in a stronger stopping for protons but a weaker stopping for tritons.The calculations of the isospin tracer show that the mn*>mp*parameter results in a higher isospin mix than the mn*<mp*parameter.The rapidity and impact parameter dependences of the isospin tracer are also studied.A constraining of the effective mass splitting using the free nucleons with high rapidity and in a central rather than peripheral collision is suggested. 展开更多
关键词 Neutron–proton effective mass splitting Nuclear stopping Isospin mix
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Observations and Simulations of the Circulation and Mixing around the Andaman-Nicobar Submarine Ridge 被引量:2
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作者 LI Yi-Neng PENG Shi-Qiu ZENG Xue-Zhi 《Atmospheric and Oceanic Science Letters》 2012年第4期319-323,共5页
Using data collected by an Acoustic Doppler Current Profiler (ADCP) on a research cruise in April 2010 in the eastern Indian Ocean, the vertical cun'ent structures surrounding the Andaman-Nicobar Submarine Ridge (... Using data collected by an Acoustic Doppler Current Profiler (ADCP) on a research cruise in April 2010 in the eastern Indian Ocean, the vertical cun'ent structures surrounding the Andaman-Nicobar Submarine Ridge (ANSR) are analyzed to investigate the hydrographic responses to the topography in this region. The results show that the topography of ANSR can induce internal waves around the submarine ridge that have a maximum current velocity of 1 m s 1 The spatial struc- ture of the turbulent kinetic energy (TKE) and shear in this region during 2010 is investigated using the high-resolution Princeton Ocean Model (POM) forced by the satellite-based Advanced Scatterometer (ASCAT) winds including the tide, The results show that the model successfully simulates the internal waves around the ANSR. Numerical experiments further indicate that both the topography and tide play an important role in the gen- eration of the internal waves in this region. 展开更多
关键词 Andaman Sea vertical mixing internal waves bottom topography effects
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Functional diversity dominates positive species mixture effects on ecosystem multifunctionality in subtropical plantations 被引量:2
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作者 Xi Li Hui Wang +4 位作者 Junwei Luan Scott X.Chang Bing Gao Yi Wang Shirong Liu 《Forest Ecosystems》 SCIE CSCD 2022年第3期417-426,共10页
Mixed-species plantations generally exhibit higher ecosystem multifunctionality than monospecific plantations.However,it is unclear how tree species functional composition influences species mixture effects on ecosyst... Mixed-species plantations generally exhibit higher ecosystem multifunctionality than monospecific plantations.However,it is unclear how tree species functional composition influences species mixture effects on ecosystem multifunctionality.We selected 171 monospecific and mixed-species plantations from nine regions across subtropical China,and quantified 13 key ecosystem functional properties to investigate how species mixture effects on ecosystem multifunctionality are modulated by functional diversity and identity.We found that ecosystem multifunctionality was significantly higher(p<0.05)in mixed tree plantations than in monospecific plantations except the mixed-conifer species plantations.Across all regions,ecosystem multifunctionality was significantly higher(p<0.05)in mixed conifer-broadleaf plantations than in monospecific plantations of the corresponding species,but not different between mixed and monospecific coniferous plantations.The magnitude of species mixture effects on ecosystem multifunctionality varied greatly with tree species compositions.Taking Cunninghamia lanceolata Lamb.as an example,the effects varied from a range of 2.0%–9.6%when mixed with a conifer species to 36%–87%when mixed with a broadleaf species.The functional diversity was the dominate driver shaping ecosystem multifunctionality,while functional identity,as expressed by community-weighted mean of specific leaf area,also had a positive effect on ecosystem multifunctionality through the increased below-ground nitrogen and phosphorus stocks regulated by specific leaf area of the mixing tree species.Our study highlights the important role of functional diversity in shaping ecosystem multifunctionality across region-wide environmental conditions.Mixed conifer-broadleaf tree plantations with distinct functional traits benefit the enhancement of ecosystem multifunctionality,and the magnitude of species mixture effects is modulated by the functional identity of tree species composition;those relationships deserve a special consideration in multifunctional management context of subtropical plantations. 展开更多
关键词 Ecosystem multifunctionality Species mixture effects Functional diversity Functional identity mixed tree plantations Monospecific plantations
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Synergistic Effect in Mixed Capillary Gas Chromatographic Stationap Phases Containing Heptakis(2,3,6-tri-o-pentyl)-β-cyclodextrin and Dibenzo-18-crown-6 被引量:1
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作者 Li Ming YUAN Ruo Nong FU +3 位作者 Xue Xian CHEN Shi Hong GUl Rong Ji DAI (Chemistry Department of Yunnan Normal University.Kunming 650092)(Department of Chemical Engineering.Beijing institute of Technology,BEijing 100081)(Solar Energy Research Institute ofyunna 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第3期223-226,共4页
used-silical capillary columns containing heptakis(2、3、6-tri-o-pentyl)-β-cyclodextrinand dibenzo-18-crown-6 were prepared.By studying the selectivity of mixed stationary phases forsome solute pairs.as well a... used-silical capillary columns containing heptakis(2、3、6-tri-o-pentyl)-β-cyclodextrinand dibenzo-18-crown-6 were prepared.By studying the selectivity of mixed stationary phases forsome solute pairs.as well as comparing with the heptakis(2.3、6-tri-O-pentyl)-β-cyclodextrin and thedibenzo-18-crown-6 used as individual stationary phase、the synergistic effects were observed.These effects were affected by the column temperature.mixed ratio and linear velocity of carrier gas. 展开更多
关键词 Gas chromatography mixed stationary phase synergistic effect heptakis(2.3.6-tri-o-pentyl)-β-cyclodextrin DIBENZO-18-CROWN-6
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Additive mixed models to study the effect of tree age and climatic factors on stem radial growth of Eucalyptus trees 被引量:1
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作者 Sileshi F.Melesse Temesgen Zewotir 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第2期463-473,共11页
The effect of tree age and climatic variables on stem radial growth of two hybrid clones of Eucalyptus was determined using longitudinal data from eastern South Africa.The stem radius of was measured weekly as the res... The effect of tree age and climatic variables on stem radial growth of two hybrid clones of Eucalyptus was determined using longitudinal data from eastern South Africa.The stem radius of was measured weekly as the response variable.In addition to tree age,average weekly temperature,solar radiation,relative humidity and wind speed were simultaneously recorded with total rainfall at the site.An additive mixed effects model that incorporates a non-parametric smooth function was used.The results of the analysis indicate that the relationship between stem radius and each of the covariates can be explained by nonlinear functions.Models that account for the effect of clone and season together with their interaction in the parametric part of the additive mixed model were also fitted.The interaction between clone and season was not significant in all cases.For analyzing the joint effect all the covariates,additive mixed models that included two or more covariates were fitted.A significant effect of tree age was found in all cases.Although tree age was the key determinant of stem radial growth,weather variables also had a significant effect that was dependent on season. 展开更多
关键词 Additive mixed effects Dendrometer trial Parametric modelling Penalized splines Weather variables
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Effects of Nitrogen Addition on the Mixed Litter Decomposition in Stipa baicalensis Steppe in Inner Mongolia 被引量:1
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作者 Wenya Li Wenchao Yu +2 位作者 Long Bai Hongmei Liu Dianlin Yang 《American Journal of Plant Sciences》 2016年第3期547-561,共15页
During the past two centuries, global changes (i.e., enhanced nitrogen deposition) have exerted profound effects on ecological processes of steppe ecosystems. We used litterbag method and mixed litters of three differ... During the past two centuries, global changes (i.e., enhanced nitrogen deposition) have exerted profound effects on ecological processes of steppe ecosystems. We used litterbag method and mixed litters of three different plant species tissues (Stipa baicalensis: Sb, Leymus chinensis: Lc and Artemisia frigid: Af), endemic to Stipa baicalensis Steppe, and measured the mass loss of mixtures over 417 days under the N addition treatment. We studied the effect of N addition (N0: no N addition;N15: 1.5 g N/m<sup>2</sup>·a;N30: 3.0 g N/m<sup>2</sup>·a;N50: 5.0 g N/m<sup>2</sup>·a;N100: 10.0 g N/m<sup>2</sup>·a;N150: 15.0 g N/m<sup>2</sup>·a) on the rate of mixed litter decomposition and nutrient dynamics change. The decomposition constant (k) of leaf mixtures was higher than that of root mixtures. The k values of leaf mixed combinations were 0.880 (Sb + Lc), 1.231 (Lc + Af), 1.027 (Sb + Lc + Af), respectively. The k value of stem was 0.806 (Lc + Af) and the root mixed combinations were 0.665 (Sb + Lc), 0.979 (Lc + Af) and 1.164 (Sb + Lc + Af), respectively. The results indicated that N addition had significantly effect on the mixed litter decomposition and nutrient releasing. The rate of plant tissues litter decomposition had different response to N addition. In the context of N addition, litter decomposition rate and nutrient dynamics were changed by synthetic effect of decaying time, specie types and N addition dose. Our findings suggested that prairie plants may adapt to environmental change by adjusting litter quality, thus retaining the stability of the steppe ecosystem. 展开更多
关键词 GRASSLAND Litter Decomposition mixed effect N Addition Mass Loss Nutrient Dynamics
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Experiment on the Fattening Effects of Mixed Silage of Wolfberry Branches on Hybrid 被引量:1
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作者 Youren DING Hua YUN +3 位作者 Ning'an MEI Jianning DING Yuping YAN Deyun YANG 《Agricultural Biotechnology》 CAS 2019年第6期57-58,67,共3页
[Objectives] This study was conducted to use the feeding value of wolfberry branches and to provide a basis for the rational use of its active ingredients and nutrients and the development of new feed resources. [Meth... [Objectives] This study was conducted to use the feeding value of wolfberry branches and to provide a basis for the rational use of its active ingredients and nutrients and the development of new feed resources. [Methods] Wolfberry branches and whole-plant corn were used to make mixed silage of wolfberry branches, which replaced different proportions of whole-plant corn silage for feeding hybrid mutton sheep, and the feeding effect of the mixed silage of wolfberry branches on hybrid mutton sheep was analyzed, which provides a technical basis for rational utilization of mulberry resources to ruminants. A single factor feeding comparison experiment was carried out. 32 hybrid mutton sheep of 8 months old with conform gender, age, body weight, physiological state and feeding management level were selected and divided into two groups, 16 in each group. [Results] The gross output value of weight gain of the experimental group was 18.06 yuan, which was higher than the CK(12.97 yuan) by 5.09 yuan. [Conclusions] The addition of the mixed silage of wolfberry branches to the diet had a positive effect on the increase of the weight gain of the hybrid mutton sheep and the reduction of the feed conversion ratio compared with the single whole-plant corn silage. 展开更多
关键词 Wolfberry branches mixed silage Hybrid mutton sheep Fattening effect
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