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“共构殖民论”辨析:荷据时代台湾地区的中国内地移民与荷兰殖民者之间的关系考察
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作者 陈思 《广东社会科学》 CSSCI 北大核心 2024年第4期99-113,285,286,共17页
“共构殖民论”认为历史上中国内地对台移民开发活动的产生和发展,是荷兰殖民者到来后主导推动的结果,宣称中国内地移民与殖民者“相互依赖”,对台湾地区进行了“合作殖民”。这不仅美化了殖民统治,也否定了自古以来两岸之间交流融合不... “共构殖民论”认为历史上中国内地对台移民开发活动的产生和发展,是荷兰殖民者到来后主导推动的结果,宣称中国内地移民与殖民者“相互依赖”,对台湾地区进行了“合作殖民”。这不仅美化了殖民统治,也否定了自古以来两岸之间交流融合不断发展、中国内地对台移民开发逐步深化的历史事实,并将后者和西方国家的殖民活动混为一谈,与“台独史观”实际上有着相似的叙事模式。但是,各种史料记载早已充分证明,引发当时对台移民活动的主要动力来自中国内地方面,当时对台移民活动的主导是中国内地官方与民间,而不是荷兰殖民者。荷兰殖民者与中国内地移民的关系绝非“相互依赖”,当时台湾地区各项产业的开发,均是建立在前者残酷剥削后者血汗的基础之上。后者与台湾地区少数民族一样,都是荷兰殖民统治下的受害者,乃至与台湾地区少数民族联合起来,以各种形式进行着反抗,是荷兰殖民者猜忌防范的重点对象。所谓“共构殖民论”,是对荷据时代的中国内地对台移民开发历史的严重歪曲。 展开更多
关键词 中国内地移民 台湾地区 荷兰殖民者 “共殖民论”
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A novel model for assessing the pore structure of tight sands and its application 被引量:9
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作者 李潮流 周灿灿 +3 位作者 李霞 胡法龙 张莉 王伟俊 《Applied Geophysics》 SCIE CSCD 2010年第3期283-291,294,共10页
Pore-structure poses great influence on the permeability and electrical property of tight sand reservoirs and is critical to the petrophysical research of such reservoirs.The uncertainty of permeability for tight sand... Pore-structure poses great influence on the permeability and electrical property of tight sand reservoirs and is critical to the petrophysical research of such reservoirs.The uncertainty of permeability for tight sands is very common and the relationship between pore- structure and electrical property is often unclear.We propose a new parameterδ,integrating porosity,maximum radius of connected pore-throats,and sorting degree,for investigating the permeability and electrical properties of tight sands.Core data and wireline log analyses show that this newδcan be used to accurately predict the tight sands permeability and has a close relation with electrical parameters,allowing the estimation of formation factor F and cementation exponent m.The normalization of the resistivity difference caused by the pore- structure is used to highlight the influence of fluid type on Rt,enhancing the coincidence rate in the Pickett crossplot significantly. 展开更多
关键词 low permeability tight sand pore-structure NMR rock physics
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Microscopic damage and dynamic mechanical properties of rock under freeze-thaw environment 被引量:25
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作者 周科平 李斌 +2 位作者 李杰林 邓红卫 宾峰 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第4期1254-1261,共8页
For understanding the rock microscopic damage and dynamic mechanical properties subjected to recurrent freeze-thaw cycles, experiments for five groups of homogeneous sandstone under different freeze-thaw cycles were c... For understanding the rock microscopic damage and dynamic mechanical properties subjected to recurrent freeze-thaw cycles, experiments for five groups of homogeneous sandstone under different freeze-thaw cycles were conducted. After freezethaw, nuclear magnetic resonance(NMR) tests and impact loading tests were carried out, from which microscopic damage characteristics of sandstone and dynamic mechanical parameters were obtained. The results indicate that the porosity increases with the increase of cycle number, the rate of porosity growth descends at the beginning of freeze-thaw, yet accelerates after a certain number of cycles. The proportion of pores with different sizes changes dynamically and the multi-scale distribution of pores tends to develop on pore structure with the continuing impact of freeze-thaw and thawing. Dynamic compressive stress-strain curve of sandstone undergoing freeze-thaw can be divided into four phases, and the phase of compaction is inconspicuous compared with the static curve. Elastic modulus and dynamic peak intensity of sandstone gradually decrease with freeze-thaw cycles, while peak strain increases. The higher the porosity is, the more serious the degradation of dynamic intensity is. The porosity is of a polynomial relationship with the dynamic peak intensity. 展开更多
关键词 ROCK freeze-thaw cycle nuclear magnetic resonance(NMR) pore structure dynamic mechanical property dynamic compression stress-strain curve
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从模块化机房到可装配式地下空间的探讨 被引量:1
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作者 吴传中 《工程建设标准化》 2021年第6期84-87,共4页
本文以详实的3D建模为依据,用Revit配合建筑专业制造了一个活生生的地下空间机房区,探讨了模块化可装配式的地下机房集中站点存在的可能性和此种设计带来的革命性优势。以平时工作中外线设计的经验为依据,展望新的地下空间模式——"... 本文以详实的3D建模为依据,用Revit配合建筑专业制造了一个活生生的地下空间机房区,探讨了模块化可装配式的地下机房集中站点存在的可能性和此种设计带来的革命性优势。以平时工作中外线设计的经验为依据,展望新的地下空间模式——"共构"在未来新区建设和使用中所带来的便利。 展开更多
关键词 模块化 地下空间 “共构”
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Numerical simulation of rock pore-throat structure effects on NMR T_2 distribution 被引量:4
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作者 王克文 李宁 《Applied Geophysics》 SCIE CSCD 2008年第2期86-91,共6页
We built a three-dimensional irregular network model which can adequately describe reservoir rock pore-throat structures. We carried out numerical simulations to study the NMR T2 distribution of water-saturated rocks.... We built a three-dimensional irregular network model which can adequately describe reservoir rock pore-throat structures. We carried out numerical simulations to study the NMR T2 distribution of water-saturated rocks. The results indicate that there is a good correlation between T2 distribution and the pore radius frequency histogram. The total T2 distribution can be partitioned into pore body and pore throat parts. The effect of parameters including throat radius, pore-throat ratio, and coordination number of the micro- pore structure on the T2 distribution can be evaluated individually. The result indicates that: 1 ) with the increase of the pore throat radius, the T2 distribution moves toward longer relaxation times and its peak intensity increases; 2) with the increase of the pore-throat ratio, the T2 distribution moves towards longer T2 with the peak intensity increasing and the overlap between pore body T2 and pore throat T2 decreasing; 3) With the increase of connectivity, the short T2 component increases and peak signal intensity decreases slightly. 展开更多
关键词 Network model NMR T2 distribution Pore structure Microstructure modeling
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Influence of Preparation Conditions on Structural Stability of Ordered Mesoporous Carbons Synthesized by Evaporation-induced Triconstituent Co-assembly Method 被引量:1
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作者 游波 杨俊 +3 位作者 雍国平 刘少民 谢卫 苏庆德 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2011年第3期365-372,I0004,共9页
Various ordered mesoporous carbons (OMCs) have been prepared by evaporation-induced trieonstituent co-assembly method. Their mesostructural stability under different carbon content, aging time and acidity were conve... Various ordered mesoporous carbons (OMCs) have been prepared by evaporation-induced trieonstituent co-assembly method. Their mesostructural stability under different carbon content, aging time and acidity were conveniently monitored by X-ray diffraction, transmission electron microscopy, and N2 sorption isotherms techniques. The results show mesostruetural stability of OMCs is enhanced as the carbon content increases from 36% to 46%, further increasing carbon content deteriorates the mesostructural stability. Increasing aging time from 0.5 h to 5.0 h make the mesostructural stability go through an optimum (2.0 h) and gradually reduce framework shrinkage of the OMCs. Highly OMCs can only be obtained in the acidity range of 0.2-1.2 mol/L HC1, when the acidity is near the isoelectrie point of silica, the resulting OMCs have the best mesostructure stability. Under the optimum condition, the carbon content of 46%, aging time of 2.0 h, and 0.2 mol/L HCl, the resulting OMCs have the best mesostrueture stability and the highest BET surface areas of 2281 m2/g. 展开更多
关键词 Triblock copolymer Mesostructural stability SELF-ASSEMBLY Ordered mesoporous carbon
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Low-Energy Electron Attachment to Serine Conformers: Shape Resonances and Dissociation Dynamics 被引量:1
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作者 王永峰 田善喜 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2017年第2期173-185,I0001,共14页
Shape resonances of electron-molecule system formed in the low-energy electron attachment to four low-lying conformers of serine (serine 1, serine 2, serine 3, and serine 4) in gas phase are investigated using the q... Shape resonances of electron-molecule system formed in the low-energy electron attachment to four low-lying conformers of serine (serine 1, serine 2, serine 3, and serine 4) in gas phase are investigated using the quantum scattering method with the non-empirical model potentials in single-center expansion. In the attachment energy range of 0-10 eV, three shape resonances for serine 1, serine 2, and serine 4 and four shape resonances for serine 3 are predicted. The one-dimensional potential energy curves of the temporary negative ions of electron-serine are calculated to explore the correlations between the shape resonance and the bond cleavage. The bond-cleavage selectivity of the different resonant states for a certain conformer is demonstrated, and the recent experimental results about the dissociative electron attachment to serine are interpreted on the basis of present calculations. 展开更多
关键词 SERINE Conformational effect Shape resonance Dissociative electron attach-ment
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Study on Structure and Performance of Starch and Styrene Graft Copolymer
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作者 田晓玲 《Agricultural Science & Technology》 CAS 2012年第1期21-23,共3页
[Objective] The paper was to study the structure and performance of starch and styrene graft copolymer. [Method] The microscopic structure of corn starch and styrene graft copolymer was analyzed by using infrared spec... [Objective] The paper was to study the structure and performance of starch and styrene graft copolymer. [Method] The microscopic structure of corn starch and styrene graft copolymer was analyzed by using infrared spectrum and scanning electron microscope, and the property of starch and styrene graft copoly- mer was confirmed through grinding experiment, tensile strength, water absorption rate, hot water resistance properties and enzymatic properties analysis. [Result] The starch and styrene graft copolymer had the properties of thermoplastic and microbial degradation. IConclusion] The starch and styrene graft copolymer is expected to be developed as a biodegradable material. 展开更多
关键词 STARCH STYRENE Graft copolymerization STRUCTURE Biodegradation characteristic
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Evidence of Ultrastructure and Physiology of F-actin as Component of Plasmodesmata 被引量:2
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作者 王冬梅 王学臣 张伟成 《Acta Botanica Sinica》 CSCD 2002年第11期1278-1285,共8页
The characters and ultrastructure of the intercellular connection were revealed in the outer epidermis of the garlic clove sheath by means of fluorescent probe TRITC_Phalloidin (TRITC_Ph) labeling combined with confoc... The characters and ultrastructure of the intercellular connection were revealed in the outer epidermis of the garlic clove sheath by means of fluorescent probe TRITC_Phalloidin (TRITC_Ph) labeling combined with confocal laser scanning microscopy (CLSM), immuno_gold labeling and transmission electron microscopy. These results show that transcellular channel is a complex of rod_like cytoplasm channel and grouped plasmodesmata (PDs) in pit. The former remains a portion of the cell protoplast. The diameter of PD is normally 60-70 nm. The PDs are the real intercellular symplasmic connections of the cells. The transcellular fibers labeled with the TRITC_Ph obviously become narrow in the primary pit fields, which is the same as the characters observed under the electron microscope. The bright fluorescent spot in the primary wall reflects the grouped PDs in pit, and hence the presence of F_actin in the PDs can be confirmed. In immuno_gold labeling experiment, a lot of gold particles were massively distributed in the rod_like cytoplasm channel and grouped PDs. The result provides effective support that these fluorescent filaments possibly are the existing form of F_actin. 展开更多
关键词 PLASMODESMATA F_actin confocal laser scanning microscopy (CLSM) ULTRASTRUCTURE Allium sativum
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A new method to construct reservoir capillary pressure curves using NMR log data and its application 被引量:5
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作者 肖亮 张伟 《Applied Geophysics》 SCIE CSCD 2008年第2期92-98,共7页
By analyzing hundreds of capillary pressure curves, the controlling factors of shape and type of capillary pressure curves are found and a novel method is presented to construct capillary pressure curves by using rese... By analyzing hundreds of capillary pressure curves, the controlling factors of shape and type of capillary pressure curves are found and a novel method is presented to construct capillary pressure curves by using reservoir permeability and a synthesized index. The accuracy of this new method is verified by mercury-injection experiments. Considering the limited quantity of capillary pressure data, a new method is developed to extract the Swanson parameter from the NMR T2 distribution and estimate reservoir permeability. Integrating with NMR total porosity, reservoir capillary pressure curves can be constructed to evaluate reservoir pore structure in the intervals with NMR log data. An in-situ example of evaluating reservoir pore structure using the capillary pressure curves by this new method is presented. The result shows that it accurately detects the change in reservoir pore structure as a function of depth. 展开更多
关键词 NMR log pore structure Swanson parameter synthesized index capillary pressure curves
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~1H and ^(13)C NMR Assignments for Amlodipine and Risperidone
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作者 杨春晖 李勤 +2 位作者 刘雪辉 赵兴凯 崔育新 《Journal of Chinese Pharmaceutical Sciences》 CAS 2004年第1期49-52,共4页
Aim To investigate the NMR spectroscopy of amlodipine and risperidone.Methods 1D NMR and 2D NMR experimental techniques of gCOSY, gHSQC and gHMBC were wsed. Results Theassignments of the ~1H and ^(13) C NMR data for t... Aim To investigate the NMR spectroscopy of amlodipine and risperidone.Methods 1D NMR and 2D NMR experimental techniques of gCOSY, gHSQC and gHMBC were wsed. Results Theassignments of the ~1H and ^(13) C NMR data for the two drugs were performed and confirmed by theevidence of J_(HF) and J_(CF). Conclusion The structures of amlodipine and risperidone wereconfirmed by careful analysis of regular 1D and 2D NMR spectroscopy. 展开更多
关键词 NMR ASSIGNMENT fluorine coupling AMLODIPINE RISPERIDONE
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A universal thermodynamic model of calculating mass action concentrations for structural units or ion couples in aqueous solutions and its applications in binary and ternary aqueous solutions 被引量:1
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作者 杨学民 赵伟洁 +2 位作者 柴国明 郭汉杰 张强 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第3期626-641,共16页
A universal thermodynamic model of calculating mass action concentrations for structural units or ion couples in ternary and binary strong electrolyte aqueous solution was developed based on the ion and molecule coexi... A universal thermodynamic model of calculating mass action concentrations for structural units or ion couples in ternary and binary strong electrolyte aqueous solution was developed based on the ion and molecule coexistence theory and verified in four kinds of binary aqueous solutions and two kinds of ternary aqueous solutions. The calculated mass action concentrations of structural units or ion couples in four binary aqueous solutions and two ternary solutions at 298.15 K have good agreement with the reported activity data from literatures after shifting the standard state and concentration unit. Therefore, the calculated mass action concentrations of structural units or ion couples from the developed universal thermodynamic model for ternary and binary aqueous solutions can be applied to predict reaction ability of components in ternary and binary strong electrolyte aqueous solutions. It is also proved that the assumptions applied in the developed thermodynamic model are correct and reasonable, i.e., strong electrolyte aqueous solution is composed of cations and anions as simple ions, H2O as simple molecule and other hydrous salt compounds as complex molecules. The calculated mass action concentrations of structural units or ion couples in ternary and binary strong electrolyte aqueous solutions strictly follow the mass action law. 展开更多
关键词 universal thermodynamic model mass action concentration activity ternary aqueous solution binary aqueous solution ion and molecule coexistence theory structural units ion couples components
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A DC-to-32GHz 2Bit MEMS Phase Shifter
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作者 娄建忠 赵正平 +2 位作者 杨瑞霞 吕苗 胡小东 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2004年第11期1386-1390,共5页
A two-bit phase shifter with distributed microelectromechanical system (MEMS) transmission line (DMTL) is developed,and a novel structure which be actuated by coplanar waveguide transmission line (CPW-actuation struct... A two-bit phase shifter with distributed microelectromechanical system (MEMS) transmission line (DMTL) is developed,and a novel structure which be actuated by coplanar waveguide transmission line (CPW-actuation structure) is proposed,which can reduce the actuation voltage significantly.The measured result,with actuation voltage less than 20V,0°/20.1°/41.9°/68.2° phase shift and -1.2dB insert loss at 20GHz,is demonstrated,and insertion loss/return loss is better than -1.8dB/-11dB from DC to 32GHz.The experimental results highlight the potential of a low-loss and broadband digital MEMS phase shifter on a high-permittivity substrate. 展开更多
关键词 MEMS phase shifter CPW-actuation structure
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Effects of synthesis conditions on layered Li[Ni_(1/3)Co_(1/3)Mn_(1/3)]O_2 positive-electrode via hydroxide co-precipitation method for lithium-ion batteries 被引量:7
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作者 胡传跃 郭军 +2 位作者 杜勇 徐洪辉 贺跃辉 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第1期114-120,共7页
Layered Li[Ni1/3Co1/3Mn1/3]O2 was synthesized with complex metal hydroxide precursors that were prepared by a co-precipitation method.The influence of coordination between ammonia and transition-metal cations on the s... Layered Li[Ni1/3Co1/3Mn1/3]O2 was synthesized with complex metal hydroxide precursors that were prepared by a co-precipitation method.The influence of coordination between ammonia and transition-metal cations on the structural and electrochemical properties of the Li[Ni1/3Co1/3Mn1/3]O2 materials was studied.It is found that when the molar ratio of ammonia to total transition-metal cations is 2.7:1,uniform particle size distribution of the complex metal hydroxide is observed via scanning electron microscopy.The average particle size of Li[Ni1/3Co1/3Mn1/3]O2 materials was measured to be about 500 nm,and the tap-density was measured to be approximately 2.37 g/cm3,which is comparable with that of commercialized LiCoO2.XRD analysis indicates that the presently synthesized Li[Ni1/3Co1/3Mn1/3]O2 has a hexagonal layered-structure.The initial discharge capacity of the Li[Ni1/3Co1/3Mn1/3]O2 positive-electrode material is determined to be 181.5 mA·h/g using a Li/Li[Ni1/3Co1/3Mn1/3]O2 cell operated at 0.1C in the voltage range of 2.8-4.5 V.The discharge capacity at the 50th cycle at 0.5C is 170.6 mA·h/g. 展开更多
关键词 layered structure coordination effect hydroxide co-precipitation cathode material lithium ion batteries
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Ultra-wideband bilateral tapered slot-line antenna fed by coplanar waveguide 被引量:1
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作者 章朋 章文勋 《Journal of Southeast University(English Edition)》 EI CAS 2011年第2期128-131,共4页
In order to broaden the bandwidth of a tapered slot- line antenna (TSA), a bilateral tapered slot-line antenna (BTSA) with a new feeding structure of coplanar waveguide (CPW) is developed. Based on the fact that... In order to broaden the bandwidth of a tapered slot- line antenna (TSA), a bilateral tapered slot-line antenna (BTSA) with a new feeding structure of coplanar waveguide (CPW) is developed. Based on the fact that the bandwidth limitation of TSA mainly depends on its feeding structure, an improved CPW-based feed structure etched on the backboard of the BTSA is adopted to perform traveling-wave transition. Both the simulation results and measurement data verify that the proposed feeding structure results in "high-pass" frequency response for antenna impedance matching. The voltage standing wave ratio (VSWR) is less than 2:1 when the frequency is higher than 3 GHz. The antenna gain exceeds 7 dBi with good radiation patterns when the bandwidth is from 4 to 16 GHz. This ultra wideband (UWB) antenna with a compact size is specially available for the electronic systems of counter-measure and microwave imaging. 展开更多
关键词 ultra wideband (UWB) tapered slot-line antenna(TSA) feeding structure coplanar waveguide (CPW)
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2D NMR Studies on the Benzodiheteropine and its Cycloaddition Products
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作者 崔育新 刘晓峰 +1 位作者 吴海涛 潘鑫复 《Journal of Chinese Pharmaceutical Sciences》 CAS 1998年第4期11-14,共4页
The signals of 1H NMR and 13 C NMR for benzodiheteropine 1 and its cycloaddtion products 2~5 were assigned by two dimensional NMR techniques. The characteristics of their structures were analyzed and ... The signals of 1H NMR and 13 C NMR for benzodiheteropine 1 and its cycloaddtion products 2~5 were assigned by two dimensional NMR techniques. The characteristics of their structures were analyzed and discussed. The boat conformation of the seven membered heteroatomic ring in these structures was interpreted on the basis of the spectrum of NOESY as well. The coupling constants of relative protons were in accord with above results. 展开更多
关键词 Benzodiheteropine 2D NMR CONFORMATION Seven membered heteroatomic ring
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Covariant Prolongation Structure of Konno-Asai-Kakuhata Equation 被引量:2
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作者 XIE Tao LI Min-Li 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第9期565-567,共3页
Based upon the covariant prolongation structures theory, we construct the sl(2, R)×R(p) prolongation structure for Konno-Asai-Kakuhata equation. By taking two and one-dimensional prolongation spaces, we obtai... Based upon the covariant prolongation structures theory, we construct the sl(2, R)×R(p) prolongation structure for Konno-Asai-Kakuhata equation. By taking two and one-dimensional prolongation spaces, we obtain the inverse scattering equations given by Konno et al. and the corresponding Riccati equation. The Baecklund transformations are also presented. 展开更多
关键词 integrable equation covariant prolongation structure Baecklund transformation
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Design and Realization of CPW Circuits Using EC-ANN Models for CPW Discontinuities
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作者 胡江 孙玲玲 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第12期2320-2329,共10页
Novel accurate and efficient equivalent circuit trained artificial neural-network (EC-ANN) models,which inherit and improve upon EC model and EM-ANN models' advantages,are developed for coplanar waveguide (CPW) d... Novel accurate and efficient equivalent circuit trained artificial neural-network (EC-ANN) models,which inherit and improve upon EC model and EM-ANN models' advantages,are developed for coplanar waveguide (CPW) discontinuities. Modeled discontinuities include : CPW step, interdigital capacitor, symmetric cross junction, and spiral inductor, for which validation tests are performed. These models allow for circuit design, simulation, and optimization within a CAD simulator. Design and realization of a coplanar lumped element band pass filter on GaAs using the developed CPW EC-ANN models are demonstrated. 展开更多
关键词 CPW DISCONTINUITIES MODELS equivalent circuit artificial neural-network band pass filter
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Preparation of AgSnO_2 composite powders by hydrothermal process 被引量:2
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作者 杨天足 杜作娟 +2 位作者 古映莹 邱晓勇 江名喜 《Journal of Central South University of Technology》 EI 2007年第2期176-180,共5页
Silver-tin oxide powders were synthesized by the hydrothermal method with Ag(NH_3)_2^+ solution and Na_2SnO_3 solution as raw materials and Na_2SO_3 as reductant. The precipitation conditions of Na2SnO3 solution and t... Silver-tin oxide powders were synthesized by the hydrothermal method with Ag(NH_3)_2^+ solution and Na_2SnO_3 solution as raw materials and Na_2SO_3 as reductant. The precipitation conditions of Na2SnO3 solution and the reduction conditions of Ag(NH_3)_2^+ were also investigated. The powders prepared were characterized by differential thermal analysis (DTA), X-ray diffraction analysis (XRD), scanning electron microscope (SEM) and energy spectrum analysis. The results show that pH value of the solution is a key parameter in the formation of Sn(OH)_4 precipitate and the reduction reaction of Ag(NH_3)_2^+ can release H+ ions, which results in synchronous precipitation of Sn(OH)_6~2- as Sn(OH)_4. The reduction of Ag(NH_3)_2^+ and precipitation of Na_2SnO_3 occur simultaneously and the coprecipitation of silver and tin oxide is reached by the hydrothermal method. The silver-tin oxide composite powders have mainly flake shape of about 0.3 μm in thickness and there exists homogeneous distribution of tin oxide and silver in the powder synthesized. 展开更多
关键词 silver-tin oxide powder hydrothermal method flake structure coprecipitation
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Community structure changes of macrobenthos in the South Yellow Sea 被引量:3
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作者 张均龙 徐凤山 刘瑞玉 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2012年第2期248-255,共8页
The ecological environment in the Yellow Sea has changed greatly from the 1950s to 1990s and this has had significant impact on marine organisms. In this study, data on soft-sediment macrobenthos occurring in depths f... The ecological environment in the Yellow Sea has changed greatly from the 1950s to 1990s and this has had significant impact on marine organisms. In this study, data on soft-sediment macrobenthos occurring in depths from 25 m to 81 m in the South Yellow Sea were used to compare changes in community structure. The agglomerative classification (CLUSTER) and multidimensional scaling (MDS) methods were applied. Five communities were recognized by cluster analysis: 1. The Yellow Sea Cold Water Mass community dominated by cold water species, which changed slightly in species composition since the 1950s; 2. The mixed community with the coexistence of cold water species and warm water species, as had been reported previously; 3. The polychaete-dominated eurythermal community in which the composition changed considerably as some dominant species disappeared or decreased; 4. The Changjiang (Yangtze) River Estuarine community, with some typical estuarine species; 5. The community affected by the Yellow Sea Warm Current. The greatest change occurred in the coastal area, which indicated that the change may be caused by human activities. Macrobenthos in the central region remained almost unchanged, particularly the cold water species shielded by the Yellow Sea Cold Water Mass. The depth, temperature and median grain size of sediments were important factors affecting the distributions of macrobenthos in the South Yellow Sea. 展开更多
关键词 benthic macrofauna community structure South Yellow Sea Yellow Sea Cold Water Mass
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