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Synergistic effects of tropical cyclones on forest ecosystems:a global synthesis 被引量:2
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作者 Weimin Xi 《Journal of Forestry Research》 SCIE CAS CSCD 2015年第1期1-21,共21页
Tropical cyclones are large-scale strong wind disturbance events that occur frequently in tropical and subtropical coastal regions and often bring catastrophic physical destruction to ecosystems and economic disruptio... Tropical cyclones are large-scale strong wind disturbance events that occur frequently in tropical and subtropical coastal regions and often bring catastrophic physical destruction to ecosystems and economic disruption to societies along their paths. Major tropical cyclones can infrequently move into the midaltitudes and inland areas. Ecologically, tropical cyclones have profound impacts on diversity, structure, succession and function of forest ecosystems. The ecological effects are both dramatic and subtle. The dramatic effects can be visible, noticeable and to some extent predictable over the short-term and relatively well documented in the literature. However, the subtle effects are often invisible, complex and at smaller scale relatively unpredictable in the long-term. Many factors, meteorologic, topographic and biologic, simultaneously interact to influence the complexity of patterns of damage and dynamics of recovery. I present a global synthesis on the effects of tropical cyclones on forest ecosystems and the complexity of forest responses, with particular attention on the response to large hurricanes in the neotropics and the temperate North America, and strong typhoons on the subtropical and temperate forests in the East and Southeast Asia. Four major aspects provide on organizational framework for this synthesis:(1) consistent damage patterns,(2) factors that influence response patterns and predict damage risks,(3) complexity of forest responses and recovery, and(4) the long-term effects. This review reveals highly variable and complex effects of tropical cyclones on forest ecosystems. A deep understanding of the synergistic effects of tropical cyclones is essential for effective forest management and biodiversity conservation. 展开更多
关键词 Large infrequent disturbance Multiplescale á Tropical cyclones Hurricanes Typhoons Complexity Tree mortality Synergistic effects
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PHOTOELECTRIC EFFECTS FROM COVALENTLY LINKED PHTHALOCYANINE COMPLEXES IN BOTH BLM AND SnO_2 PHOTOVOLTAIC CELL
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作者 Zhi Chu BI Xin Li ZHAO +3 位作者 Yue Ying QIAN Shu Yin SHEN Jia Yong YU Hui Jun XU 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第7期565-568,共4页
Covalently linked phthalocyanine complexes were incorporated in bilayer lipid membranes(BLN) and deposited on SnO_2 transparent electrodes, Their photovoltages were measured and compared. It has been found that a more... Covalently linked phthalocyanine complexes were incorporated in bilayer lipid membranes(BLN) and deposited on SnO_2 transparent electrodes, Their photovoltages were measured and compared. It has been found that a more favorable orientation and closer proximity are attained in the diad compounds between the donor (phthalocyanine)-acceptor(anthraquinone) pair than in the simple compound for efficient light-induced charge separation and transfer. The triad compound is the best among all tested compounds. 展开更多
关键词 BLM PHOTOELECTRIC effects FROM COVALENTLY LINKED PHTHALOCYANINE COMPLEXES IN BOTH BLM AND SnO2 PHOTOVOLTAIC CELL SNO
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Composting MSW and sewage sludge with effective complex microorganisms 被引量:18
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作者 XiBD LiuHL 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2002年第2期264-268,共5页
The effects of complex microorganisms in composting process of the municipal solid waste (MSW) and sludge were examined through inspecting biomass, temperature, oxygen consumption, organic mater, and C/N (the ratio of... The effects of complex microorganisms in composting process of the municipal solid waste (MSW) and sludge were examined through inspecting biomass, temperature, oxygen consumption, organic mater, and C/N (the ratio of carbon and nitrogen). The experimental results shows: complex microorganisms are effective to compose organic matter and speedup composting change into humus. 展开更多
关键词 effective complex microorganisms(ECM) temperature oxygen consumption organic matter C/N ratio
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Methane and Nitrous Oxide Emissions from Rice-Duck and Rice-Fish Complex Ecosystems and the Evaluation of Their Economic Significance 被引量:13
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作者 YUAN Wei-ling CAO Cou-gui LI Cheng-fang ZHAN Ming CAI Ming-li WANG Jin-ping 《Agricultural Sciences in China》 CAS CSCD 2009年第10期1246-1255,共10页
Rice-duck (RD) and rice-fish (RF) ecological systems are major complex planting and breeding models of rice paddy fields in southern China. Studying the methane (CH4) and nitrous oxide (N2O) emissions and thei... Rice-duck (RD) and rice-fish (RF) ecological systems are major complex planting and breeding models of rice paddy fields in southern China. Studying the methane (CH4) and nitrous oxide (N2O) emissions and their economic value from these two ecosystems can provide theoretical and practical basis for further development and utilization of these classical agricultural techniques. CH4 and N2O emissions from RD and RF ecological systems were measured in situ by using static chambers technique. Using global warming potentials (GWPs), we assessed the greenhouse effect of CH4 and N2O and their economic value. Results showed that the peaks of CH4 emission fluxes from RD and RF appeared at full tillering stage and at heading stage, and the average emission fluxes were significantly (P〈 0.05) lower than that from CK. N2O fluxes remained low when the field is flooded and high after draining the water. Compared with CK, the total amount of N2O emissions was significantly (P〈0.05) higher and slightly lower than those from RD and RF, respectively. In 2006 and 2007, the total greenhouse effect of CH4 and N20 from RD and RF were 4 728.3 and 4 611 kg CO2 ha^-1, 4 545 and 4 754.3 kg CO2 ha^-1, respectively. The costs of greenhouse effect were 970.89 and 946.81 RMB yuan ha^-1, and 933.25 and 976.23 RMB yuan ha^-1, respectively, which were significant lower than those from CK (5 997.6 and 5 391.5 RMB yuan ha^-1). Except for the environment cost of CH4 and N2O, the economic benefits from RD and RF were 2 210.64 and 4 881.92 RMB yuan ha^-1; 3 798.37 and 5 310.64 RMB yuan ha^-1, respectively, higher than those from CK. Therefore, RD and RF complex ecological planting and breeding models can effectively decrease and control CH4 and N2O emissions, and they are two of the effective strategies to reduce greenhouse gases from rice paddy fields and contribute in alleviating global warming. Thus, their adoption is important to the environment together with their economy benefits. 展开更多
关键词 methane emission nitrous oxide emission rice-duck complex ecosystem rice-fish complex ecosystem greenhouse effect economic benefit
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Effect of intermediate principal stress on strength of soft rock under complex stress states 被引量:1
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作者 马宗源 廖红建 党发宁 《Journal of Central South University》 SCIE EI CAS 2014年第4期1583-1593,共11页
A series of numerical simulations of conventional and true triaxial tests for soft rock materials using the three-dimensional finite difference code FLAC3D were presented. A hexahedral element and a strain hardening/s... A series of numerical simulations of conventional and true triaxial tests for soft rock materials using the three-dimensional finite difference code FLAC3D were presented. A hexahedral element and a strain hardening/softening constitutive model based on the unified strength theory(UST) were used to simulate both the consolidated-undrained(CU) triaxial and the consolidated-drained(CD) true triaxial tests. Based on the results of the true triaxial tests simulation, the effect of the intermediate principal stress on the strength of soft rock was investigated. Finally, an example of an axial compression test for a hard rock pillar with a soft rock interlayer was analyzed using the two-dimensional finite difference code FLAC. The CD true triaxial test simulations for diatomaceous soft rock suggest the peak and residual strengths increase by 30% when the effect of the intermediate principal stress is taken into account. The axial compression for a rock pillar indicated the peak and residual strengths increase six-fold when the soft rock interlayer approached the vertical and the effect of the intermediate principal stress is taken into account. 展开更多
关键词 soft rock strength strain-softening complex stress state effect of intermediate principal stress
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CRYSTAL STRUCTURE AND SHG EFFECT OF COMPLEX [Zn(POM)_2Br_2]
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作者 Song Xian LI Zhe Ming WANG +1 位作者 Jian Zhong CHEN Wen Yue SUDepartment of Chemistry,Fuzhou University,Fuzhou,350002 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第5期397-398,共2页
[Zn(POM)_2Br_2](POM is 3-Methyl-4-Nitropyridine-1-Oxide),C_(12)H_(12)Br_2N_4O_6Zn, Mr=533.44,triclinic,P1,a=11.450(3),b=13.027(2),c=6.605(1),α=101.25(1),β=96.96(2), γ=108.06(2)°,V=901.2(4)~3,Z=2,D_c=1.97g·... [Zn(POM)_2Br_2](POM is 3-Methyl-4-Nitropyridine-1-Oxide),C_(12)H_(12)Br_2N_4O_6Zn, Mr=533.44,triclinic,P1,a=11.450(3),b=13.027(2),c=6.605(1),α=101.25(1),β=96.96(2), γ=108.06(2)°,V=901.2(4)~3,Z=2,D_c=1.97g·cm^(-3),(MoK_α)=0.71069,F(000)=520, μ=58.21cm^(-1),final R=0.040 for 2192 observed reflections,T=296K.The compound is a mononuclear complex,containing a tetrahedrally coordinated zinc atom. 展开更多
关键词 POM CRYSTAL STRUCTURE AND SHG EFFECT OF COMPLEX Br ZN SHG
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Complex Effective Relative Permittivity of Soil Samples from the Taunus Region (Germany) 被引量:1
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作者 Katja Lauer Christian Albrecht +1 位作者 Christina Salat Peter Felix-Henningsen 《Journal of Earth Science》 SCIE CAS CSCD 2010年第6期961-967,共7页
The most important parameter affecting ground-penetrating radar (GPR) measurements is the complex effective relative permittivity εr^*,eff because it controls the propagation velocity and the reflection of GPR pul... The most important parameter affecting ground-penetrating radar (GPR) measurements is the complex effective relative permittivity εr^*,eff because it controls the propagation velocity and the reflection of GPR pulses. Knowing εr^*,eff of soils passed through by electromagnetic waves increases accuracy in soil thickness and interface identification. Complex effective relative permittivity εr^*,eff= εr^*,eff - jεr^*,effof 25 soil samples with textures ranging from loamy sand to silty clay was measured using the two-electrode parallelplate method. The measurements were conducted at defined water contents for frequencies from 1 MHz to 3 GHz. The results confirm the frequency dependence of εr^*,eff and show that the dielectric behavior of soil-water mixtures is a function of water content. Applying the experimental data of this study with predictions based on the empirical model by Toppet aL (1980), we find that Topp et aL's curve tends to underestimate the real part of εr^*,eff measured. Along with frequency and water content, soil texture and organic matter affect soil permittivity. Moreover, the real part of εr^*,eff increases at higher dry bulk densities. Output from our calibration model enables us to predict εr^*,eff for the soil samples which were tested under the actual in situ soil water content. This results in high accuracy of soil thickness prediction. 展开更多
关键词 ground-penetrating radar (GPR) complex effective relative permittivity soil sample.
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Complex effective depth approximation for soft solid bottom 被引量:1
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作者 JIANG Dejun (Institute of Acoustics, Academia Sinica Beijing 100080) 《Chinese Journal of Acoustics》 1997年第3期260-272,共13页
In this paper, the approximate equation of Chapman's (real) effective depth for Pekeris guide is extended to the complex effective depth approximation whose real and imaginary parts explicate respectively the phas... In this paper, the approximate equation of Chapman's (real) effective depth for Pekeris guide is extended to the complex effective depth approximation whose real and imaginary parts explicate respectively the phase change and energy loss on reflection. It is shown that the homogeneous acoustic field, which comprises the complex effective depth approximation,closely reproduces the character of low modes at small grazing angles, and calculates effectively the acoustic field at longer ranges in shallow water. Application of the complex effective depth approximation can be extended to bottoms having two soft solid layers. 展开更多
关键词 mode Complex effective depth approximation for soft solid bottom
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Syntheses and structures of tetranuclear Zn(Ⅱ) complexes with in situ generated macrocyclic Schiff base ligands:Applications in Zn^(2+) sensing 被引量:1
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作者 Cai-Xia Ding Chang-Hua He Yong-Shu Xie 《Chinese Chemical Letters》 SCIE CAS CSCD 2013年第6期463-466,共4页
Three novel Zn(II) complexes,[Zn4L1Cl4]-3H2O(1),[Zn4L2Cl4]-2DMF(2) and[Zn4L^3Cl4]H2O(3),have been synthesized and structurally characterized.In these complexes,interesting 32-membered dodecadentate macrocyclic... Three novel Zn(II) complexes,[Zn4L1Cl4]-3H2O(1),[Zn4L2Cl4]-2DMF(2) and[Zn4L^3Cl4]H2O(3),have been synthesized and structurally characterized.In these complexes,interesting 32-membered dodecadentate macrocyclic ligands were generated in situ by '2 + 2' type condensation reactions between a tetraamine and various dialdehydes.All the complexes are isostructurally tetranuclear Zn(Ⅱ) complexes,containing endogenous alkoxo and phenoxo bridges.Applications of the macrocyclic ligands as Zn^2+ sensors have been investigated.Take H4L^1 for example,it exhibits a 4-fold fluorescence enhancement upon the addition of 2 equiv.of Zn^2+ in MeOH. 展开更多
关键词 Macrocyclic ligand Schiff base Zn(Ⅱ) complexes Fluorescent enhancement CHEF effect
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Study on the key problems of interaction between microwave and chemical reaction
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作者 YANG Xiaoqing HUANG Kama 《Frontiers of Electrical and Electronic Engineering in China》 CSCD 2007年第4期473-480,共8页
Microwave has been found as an efficient heating method in chemical industry.However,in present days the interaction between microwave and chemical reactions has not been deeply understood,which restricts a wider appl... Microwave has been found as an efficient heating method in chemical industry.However,in present days the interaction between microwave and chemical reactions has not been deeply understood,which restricts a wider application of high power microwave in chemical industry.In this paper,the key problems of interaction between microwave and chemical reaction are investigated,such as complex effective permittivity of chemical reaction,simulation of microwave heating on chemical reaction and non-thermal effect of microwave,which will enhance further knowledge of the mechanism of interaction between microwave and chemical reaction.Moreover,such an analysis is beneficial for handling with difficulties in application of microwave chemical industry. 展开更多
关键词 MICROWAVE chemical reaction INTERACTION complex effective permittivity numerical simulation non-thermal effect
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A coupled-mode sound propagation model with complex effective depth
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作者 MO Yaxiao PIAO Shengchun +1 位作者 ZHANG Haigang LI Li 《Chinese Journal of Acoustics》 2014年第4期348-358,共11页
A coupled-mode sound propagation model with complex effective depth is presented,in order to involve the effect of branch line integral for acoustic field in a range-dependent waveguide.The equations of motion and con... A coupled-mode sound propagation model with complex effective depth is presented,in order to involve the effect of branch line integral for acoustic field in a range-dependent waveguide.The equations of motion and continuity are used to obtain the coupled equations,which satisfy boundary conditions in the waveguide with varying topography and contain one coupling matrix.Meanwhile,the couplings between discrete and continuous spectrum are dealt with based on complex effective depth theory.Numerical simulations show that the accuracy of transmission loss is improved by the coupled mode model when eigenvalues of trapped modes are located near the branch point.The acoustic field in a non-horizontally stratified waveguide can be calculated efficiently and accurately by this model,and the energy corresponding to trapped modes,leaky modes and branch line integral can be considered adequately. 展开更多
关键词 MODE A coupled-mode sound propagation model with complex effective depth LINE
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Length-regulation in the self-association of actin and the effect of platinum complexes
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作者 曾慧慧 卢景芬 +1 位作者 丁友真 王夔 《Chinese Science Bulletin》 SCIE EI CAS 1995年第17期1492-1493,共2页
The evidence on the length-regulation in the self-association of actin is conflicting andits interpretation relies heavily on the character of the measurement method. By quasi-elastically light scattering (QELS) measu... The evidence on the length-regulation in the self-association of actin is conflicting andits interpretation relies heavily on the character of the measurement method. By quasi-elastically light scattering (QELS) measurements. the change of the polymerlength as a function of time and the effect of ATP have been studied. QELS studies re-vealed that there is a length-regulation stage in self-association of actin which is not in- 展开更多
关键词 length time Length-regulation in the self-association of actin and the effect of platinum complexes
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Interaction of benzene-1,3-disulfonylamid-kriptofix[22] with iodine in chloroform and dichloromethane solutions
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作者 Tayyebeh Madrakian Sara Heidari 《Chinese Chemical Letters》 SCIE CAS CSCD 2014年第10期1375-1378,共4页
The interaction of iodine as an cr-acceptor with a synthetic ligand,benzene-1,3-disulfonylamid-kriptofix[22](BDSAK) as a π-donor has been investigated spectrophotometrically in chloroform(CHCl3) and dichlorometh... The interaction of iodine as an cr-acceptor with a synthetic ligand,benzene-1,3-disulfonylamid-kriptofix[22](BDSAK) as a π-donor has been investigated spectrophotometrically in chloroform(CHCl3) and dichloromethane(DCM) solutions.The results of mole ratio plots and Job's method show the stoichiometry of complexation I2/BDSAK is 1:1.Stability constants have been calculated in various temperatures and thermodynamic parameters have also been determined from the temperatures dependence of the stability constants by using van't Hoff equation.The results indicate the iodine complex with BDSAK is enthalpy stabilized but entropy destabilized. 展开更多
关键词 Charge transfer complex Iodine Spectrophotometry Solvent effect
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Template-directed synthesis of pyridazine-containing tetracationic cyclophane for construction of[2]rotaxane
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作者 Qiu-Sheng Fang Ling Chen Qing-Yan Liu 《Chinese Chemical Letters》 SCIE CAS CSCD 2017年第5期1013-1017,共5页
Benefiting from its bent molecular structure,3,6-pyridazinyl contained tetracationic cyclophane(1) is synthesized by template-directed method with high isolated yield up to 92%.This template-directed strategy is fur... Benefiting from its bent molecular structure,3,6-pyridazinyl contained tetracationic cyclophane(1) is synthesized by template-directed method with high isolated yield up to 92%.This template-directed strategy is further utilized to efficiently construct [2]rotaxane. 展开更多
关键词 Tetracationic cyclophane Template effect Inclusion complex π-Stacking Rotaxane
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