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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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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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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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Effect of intermediate principal stress on strength of soft rock under complex stress states 被引量:2
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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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Study on fluorescence properties of rare earth complexes influenced by steric effect 被引量:5
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作者 袁伟 崔玉民 +7 位作者 师瑞娟 陶栋梁 王永忠 张文保 陈继堂 孙林 刘少轩 徐怡庄 《Journal of Rare Earths》 SCIE EI CAS CSCD 2011年第11期1013-1017,共5页
The rare earth complexes Tb(o-BrBA)3,Tb(m-BrBA)3 and Tb(p-BrBA)3 were synthesized using o-,m-,p-bromo benzoic acids(2-bromo benzoic acid,3-bromo benzoic acid and 4-bromo benzoic acid) as ligand,respectively.Th... The rare earth complexes Tb(o-BrBA)3,Tb(m-BrBA)3 and Tb(p-BrBA)3 were synthesized using o-,m-,p-bromo benzoic acids(2-bromo benzoic acid,3-bromo benzoic acid and 4-bromo benzoic acid) as ligand,respectively.The UV spectra showed that the absorption ability of Tb(m-BrBA)3 was the strongest.However,the fluorescent intensity of Tb(o-BrBA)3 was the weakest.The effect of the molecular structure,the energy level of Tb3+ and energy transfer efficiency from ligands to Tb3+ were discussed to explain the experimental results.The results indicated that,due to the large atomic radius of bromine,the steric effect caused by the different substitution bromine on the benzene ring might strongly affect the bond length formed by the coordination atoms and Tb3+.The longer the bond length was,the lower the efficiency of energy transfer was,and the weaker the fluorescent intensity was. 展开更多
关键词 terbium complexes bromo benzoic acid steric effect fluorescent spectrum rare earths
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Effects of Y(Ⅲ) Ions on the Fluorescence Properties of Ce(Ⅲ) Ion and the Organic Ligands in the Complex 被引量:3
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作者 LI Wen-lian. (Changchun Institute of Physics and the Excited State Process Laboratory, Chinese Academy of Sciences , Changchun , 1 30021 ) Takayuku Mishima , Gin-Ya Adachi and Jiro Shiokawa (Department of Applied Chemistry, Faculty of Engineering, 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1997年第3期189-194,共6页
The enhancement effects of Y ( Ⅲ) ions on the fluorescence of Ce ( Ⅲ) in Ce ( Ⅲ)-Y ( Ⅲ)-PMMA (polymethylmethacrylate ) or Ce ( Ⅲ)-Y ( Ⅲ)-PVC (polyvinyl chloride ) complex systems were observed. The influence of ... The enhancement effects of Y ( Ⅲ) ions on the fluorescence of Ce ( Ⅲ) in Ce ( Ⅲ)-Y ( Ⅲ)-PMMA (polymethylmethacrylate ) or Ce ( Ⅲ)-Y ( Ⅲ)-PVC (polyvinyl chloride ) complex systems were observed. The influence of Y ( Ⅲ) ions on the emission spectra of PMMA ligands in PMMA-Y ( Ⅲ) and the fluorescent enhance- ment of Y( Ⅲ) on Ce( Ⅲ) emission in PMMA-Ce-Y by Y( Ⅲ) ion were studied. It was also of interest to note that when Y ( Ⅲ) ions were added into PMMA and into bpy(bipyridine ) , respectively , the emission spectrum of PMMA ligands was split into fine structure bands by Y ( Ⅲ) , and the fluorescence intensities of bpy ligands in bpy-Y ( Ⅲ) complexes were considerably increased. 展开更多
关键词 effect Fluorescence properties Organic ligand complex
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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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POLYMER SUPPORT EFFECTS OF METAL COMPLEXES FOR CATALYSIS
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作者 李弘 何炳林 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1998年第4期362-369,共8页
In the course of investigating the catalytic behavior of metal complexes for ring opening metathesis polymerization of cycloolefins, metathesis, hydroformylation and selective hydrogenation of olefins experimental res... In the course of investigating the catalytic behavior of metal complexes for ring opening metathesis polymerization of cycloolefins, metathesis, hydroformylation and selective hydrogenation of olefins experimental results time and again indicate the presence of effects of macromolecular supports - the utilization of macromolecular supports increases obviously the activity, selectivity, and stability of the catalysts and so as to increase the conversion of substrates, yields of reactions, properties of formed polymers and so on. Discussed these effects on the basis of the authors' experiments. (Author abstract) 18 Refs. 展开更多
关键词 polymer supported catalysts metal complexes support effects
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Bacteriostatic Effect of Cerium Humic Acid Complex
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作者 张辉 冯嘉 王和 《Journal of Rare Earths》 SCIE EI CAS CSCD 1999年第3期237-237,共1页
关键词 rare earths cerium humic acid complex bacteriostatic effect
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Ultrafast Optical Kerr Effect of ConjugatedSilver Phenylacetylide Complex Oligomer
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作者 Yi Hui XU Li LIN +5 位作者 Jia Gang LUO Boon K. TEO Zong Ju XIA Ying Hua ZOU Hut Ying CHEN (1Department of Chemistry. University of Hinois at Chicago. Chicago. IL 60680. USA2Department of Physics. Mesoscopic Physics Laboratory. Peking University,Beijing 1008713 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第9期793-794,共2页
Silver phenylacetylide oligomer was found to exhibit prominent third-order nonlinear optical property, with susceptibility chi((3)) of 2.4x10(-14) esu (10(-4) mol/L in 1:1 dimethyl sulfoxide/CHCl3 mixed solution) and ... Silver phenylacetylide oligomer was found to exhibit prominent third-order nonlinear optical property, with susceptibility chi((3)) of 2.4x10(-14) esu (10(-4) mol/L in 1:1 dimethyl sulfoxide/CHCl3 mixed solution) and second-order hyperpolarizability gamma of 5.18x10(-32) esu via heterodyned ultrafast optical Kerr effect measurement. It existed mainly as 1:1 complex oligomers and polymers as characterized by mass spectroscopy and elemental analysis etc. 展开更多
关键词 silver phenylacetylide conjugated complex optical Kerr effect
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POLYMER NETWORK-POLY(ETHYLENE GLYCOL)COMPLEXES WITH SHAPE MEMORY EFFECT
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作者 Yi-ping Cao +1 位作者 C.W.Yip 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2003年第1期29-33,共5页
The complexes of poly(methacrylic acid-co-methyl methacrylate) network with poly(ethylene glycol) stabilized byhydrogen bonds were prepared. By introducing the poly(ethylene glycol), a large difference in storage modu... The complexes of poly(methacrylic acid-co-methyl methacrylate) network with poly(ethylene glycol) stabilized byhydrogen bonds were prepared. By introducing the poly(ethylene glycol), a large difference in storage modulus below andabove the glass transition temperature occurred and the complexes exhibited shape memory behaviors. The morphology ofcomplexes was studied by using DSC, WAXD, and DMA. The results indicate that the fixed phase of this kind of novelshape memory materials is the network, and the reversible phase is the amorphous state of PEG:PMAA complex phase. Theshape recoverability almost reaches 100%. This type of complexes can be regarded as a novel shape memory network. 展开更多
关键词 Hydrogen bonded complex Shape memory effect Storage modulus ratio
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The Double-Double Effect of Lanthanide Complexes with Styrene-Acrylic Acid Copolymer
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作者 于广谦 李玉良 刘丛明 《Journal of Rare Earths》 SCIE EI CAS CSCD 1992年第2期148-150,共3页
The double-double (or tetrad) effect of low molecular lanthanide complexes has been reportedsince the effect was discovered by Fidelis and Siekierski.However,so far no description concerning thedouble-double effect of... The double-double (or tetrad) effect of low molecular lanthanide complexes has been reportedsince the effect was discovered by Fidelis and Siekierski.However,so far no description concerning thedouble-double effect of macromolecular lanthanide complexes has been published in literature.We have been successful in preparing lanthanide complexes with styrene-acrylic acid copolymer,someof which exhibite high activitiest in butadiene polymerization.It was found that the complexes showedthe double-double effect as they were characterized.In the present paper,the SAAC·Ln IR spectra whichcharacterize the double-double effect have been discussed in detail. 展开更多
关键词 Double-double effect Lanthanide complexes COPOLYMER
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EFFECT OF WATER ON THE CONDUCTIVITY OF PPQ (ClO_4^-) COMPLEX
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作者 张驰 卢风才 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1993年第1期8-15,共8页
The preparation of conducting PPQ film was first reported in the previous paper. It is very interesting that this film is highly sensitive to moisture in air. The hydration and dehydration of the film are accompanied ... The preparation of conducting PPQ film was first reported in the previous paper. It is very interesting that this film is highly sensitive to moisture in air. The hydration and dehydration of the film are accompanied by change not only in color but also in conductivity and UV-visible spectrum. The conducting PPQ is reduced to PPQ and loses its conductivity after being soaked in water. 展开更多
关键词 POLYPHENYLQUINOXALINE ClO_4^- complex Electrical conductivity Water effect
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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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Study on the Complexity of the Bullwhip Effect
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作者 LU Yingjin, TANG Yong, Tang Xiaowo (School of Management, University of Electronic Science and Technology of China Chengdu 610054 China) 《Journal of Electronic Science and Technology of China》 2004年第3期86-91,共6页
Recent years have witnessed a rapid growth of interest in the study of the dynamic behavior of replenishment rules of bullwhip effect. We prove that bullwhip effect and butterfly effect share a same the self-oscillati... Recent years have witnessed a rapid growth of interest in the study of the dynamic behavior of replenishment rules of bullwhip effect. We prove that bullwhip effect and butterfly effect share a same the self-oscillation amplifying mechanism that is the ordering decisions the supplier self-oscillation amplify the perturbations brought by the errors in the processing of retailers' demand information. This results as an explicit self-similar structure of the sensitivity of the system to the initial values duty to the nonlinear mechanism. In this paper, the causes process of the bullwhip effect is described as the internal nonlinear mechanism and study on the complexity of bullwhip effect for order-up-to policy under demand signal processing. The methodology is based on fractal and chaotic theory and allows important insights to be gained about the complexity behavior of bullwhip effect. 展开更多
关键词 the bullwhip effect complexity theory order-up-to policy demand signal processing
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Enhanced effect of dimension of receptor-ligand complex and depletion effect on receptor-mediated endocytosis of nanoparticles
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作者 刘野 高庆庆 +4 位作者 刘益军 赵闯 毛宗良 胡林 刘艳辉 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第12期48-54,共7页
We present an extended analytical model including the depletion effect and the dimension of ligand-receptor complex, aiming to elucidate their influences on endocytosis of spherocylindrical nanoparticles (NPs). It i... We present an extended analytical model including the depletion effect and the dimension of ligand-receptor complex, aiming to elucidate their influences on endocytosis of spherocylindrical nanoparticles (NPs). It is found that the dimension of ligand-receptor complex (δ) and the depletion effect interrelatedly govern the optimal conditions of NP endocytosis. The endocytosis phase diagram constructed in the space of NP radius and relative aspect ratio indicates that the endocytosis of NP is enhanced evidently by reducing the optimal radius and the threshold radius of endocytosed NP. Meanwhile, through thermodynamic and kinetic analysis of the diffusion of receptors, the dependence of diffusion length on depletion effect and the dimension of ligand-receptor complex can be identified in great detail. For small aspect ratio, diffusion length decreases with increasing concentration c of small bioparticles in cellular environment. Endocytosis speed corresponding to large radius R and high concentration c of small bioparticles strongly depends on the increasing (2r-δ). These results may show some highlights into the conscious design of NPs for diagnostic agents and therapeutic drug delivery applications. 展开更多
关键词 cellular uptake depletion effect dimension of receptor-ligand complex elasticity theory
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Effects of heat shock protein-antigen peptide complexes (HACs) in melanoma B16 cell line on transplanted tumor development in mice
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作者 GONG Shou liang,YANG Ying,LI Xiu juan,FU Shi bo,SUN Zu yue,CHEN Sha li,LI Xiu yi (MH Radiobiology Research Unit,Jilin University,Changchun 130021 China) 《白求恩医科大学学报》 CSCD 北大核心 2001年第5期457-460,共4页
目的 :建立黑色素瘤 B16细胞热休克蛋白 -抗原肽复合物 (HACs)的制备方法并测其抑瘤效应。方法 :应用 Sephacryl S- 2 0 0凝胶过滤制备 HAC粗提物 ,应用 SDS- PAGE纯化 HACs,并测其抑瘤效应。结果 :应用 SDS- PAGE纯化的 HAC6 0、 HAC75... 目的 :建立黑色素瘤 B16细胞热休克蛋白 -抗原肽复合物 (HACs)的制备方法并测其抑瘤效应。方法 :应用 Sephacryl S- 2 0 0凝胶过滤制备 HAC粗提物 ,应用 SDS- PAGE纯化 HACs,并测其抑瘤效应。结果 :应用 SDS- PAGE纯化的 HAC6 0、 HAC75和 HAC97不同程度地降低肿瘤发生率 ,延迟肿瘤发生时间和减慢肿瘤生长速度。结论 :6 0 0 0 0~ 970 0 0 展开更多
关键词 黑色素瘤 B16细胞 热休克蛋白-抗原肽复合物 HACs 抑瘤效应
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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:15
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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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Study of Complexes of Lanthanum with Amino Acids by Titration Calorimeter 被引量:2
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作者 Ye Gang, Wang Cun-xin, Qu Song-sheng College of Chemistry and Environment Science, Wuhan University, Wuhan 430072, China 《Wuhan University Journal of Natural Sciences》 EI CAS 2000年第4期479-484,共6页
The stability constants and thermodynamic functions for complexes of lanthanum with eight kind of amino acids according to 1∶1 and 1∶2 in proportion have been determined by titration calorimeter at 298.15 K. The ent... The stability constants and thermodynamic functions for complexes of lanthanum with eight kind of amino acids according to 1∶1 and 1∶2 in proportion have been determined by titration calorimeter at 298.15 K. The enthalpy change makes a predominant contribution to the stability of these complexes. The ring in amino acid associated with lanthanum ion helps to enhance the stability of complexes. Steric effects between rings in complexes leads to that the equilibrium constants of reaction of the complexes (1∶2) is much less than that of the complexes (1∶1). 展开更多
关键词 titration calorimeter rare earth amino acid complexES steric effects
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