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地图异构变换的数学模型及其在地图发展演进中的意义 被引量:7
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作者 钟业勋 《测绘工程》 CSCD 1996年第3期8-14,共7页
给出了地图图象异构变换的数学模型,如制图选取、制图综合等。这些模型已为地图编制中的经验事实所验证并作为实例给出。图象异构变换推动着地图的发展与进步。
关键词 地图 异构变换 数学模型 制图 图象变换
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《说文解字注》句法变换考察
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作者 马立春 《贵州师范学院学报》 2019年第4期46-51,共6页
《说文解字注》是清代段玉裁文字训诂的巨著。段氏在解字释词时,非常重视语法分析,其中所采用的句法变换方法是其一大特点。统计出《说文解字注》用于变换的例数共103例,这些句法变换的类型繁多,既有同构变换,又有异构变换,同时展现了... 《说文解字注》是清代段玉裁文字训诂的巨著。段氏在解字释词时,非常重视语法分析,其中所采用的句法变换方法是其一大特点。统计出《说文解字注》用于变换的例数共103例,这些句法变换的类型繁多,既有同构变换,又有异构变换,同时展现了移位、替换、添加、删略、分离、变性等现代变换规则,体现了段氏对汉语语法特点的熟谙,显现了段氏独到的语法观念。 展开更多
关键词 《说文解字注》 同构变换 异构变换 变换规则
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Preparation of Conjugated Linoleic Acid and Identification of Its Isomers 被引量:9
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作者 郭诤 张根旺 孙彦 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2003年第2期130-135,共6页
Conjugated linoleic acid (CLA) is a kind of fatty acid with physiological activities and potential application prospect. A synthesis method of conjugated linoleic acid and a purification technology were studied. CLA w... Conjugated linoleic acid (CLA) is a kind of fatty acid with physiological activities and potential application prospect. A synthesis method of conjugated linoleic acid and a purification technology were studied. CLA was prepared and purified by urea-complexation and conjugation using safflower oil as raw material. The purity of CLA and total recovery of the product was more than 95% and 48%, respectively. The main isomers produced in alkali-catalyzed conjugation were identified by gas chromatography (GC) linked to mass spectrometry (MS) and Fourier transform infrared spectroscopy (FTIR). The total amount of the two main isomers (9cis, 11trons-and 10trans, 12cis-CLA) determined by GC was more than 90% of the product. 展开更多
关键词 linoleic acid conjugated linoleic acid urea-complexation alkali-catalyzed conjugation IDENTIFICATION safflower oil
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High-Throughput Screening Using Fourier-Transform Infrared Imaging 被引量:2
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作者 Erdem Sasmaz Kathleen Mingle Jochen Lauterbach 《Engineering》 SCIE EI 2015年第2期234-242,共9页
Efficient parallel screening of combinatorial libraries is one of the most challenging aspects of the high- throughput (HT) heterogeneous catalysis workflow. Today, a number of methods have been used in HT catalyst ... Efficient parallel screening of combinatorial libraries is one of the most challenging aspects of the high- throughput (HT) heterogeneous catalysis workflow. Today, a number of methods have been used in HT catalyst studies, including various optical, mass-spectrometry, and gas- chromatography techniques. Of these, rapid-scanning Fourier-transform infrared (FTIR) imaging is one of the fastest and most versatile screening techniques. Here, the new design of the 16-channel HT reactor is presented and test results for its accuracy and reproducibility are shown. The performance of the system was evaluated through the oxidation of CO over commercial Pd/AI203 and cobalt oxide nanoparticles synthesized with different reducer-reductant molar ratios, surfactant types, metal and surfactant concentrations, synthesis temperatures, and ramp rates. 展开更多
关键词 HIGH-THROUGHPUT FTIR imaging SCREENING cobalt oxide CO oxidation
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Study of Dye Absorption in Carbon Nanotube-Titanium Dioxide Heterostructures
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作者 Marianna Barberio Alessandra Imbrogno Davide Remo Grosso Assunta Bonanno Fang Xu 《Journal of Chemistry and Chemical Engineering》 2015年第4期245-252,共8页
In this work, the authors present a study of dye absorption in TiO2 doped with CNTs (carbon nanotubes). Absorption decreases exponentially with the increase of CNTs in the film, while morphological characterization,... In this work, the authors present a study of dye absorption in TiO2 doped with CNTs (carbon nanotubes). Absorption decreases exponentially with the increase of CNTs in the film, while morphological characterization, conducted by SEM (scanning electron microscope) and TEM (transmission electron microscope) microscopes, suggests that this behavior is strongly related to morphological structure of grown films. For CNTs amounts greater than 1%, the authors observe the formation of CNTs clusters randomly distribute on TiO2 bulk, which strongly reduces the film porosity quenching the dye absorption. Comparison with optical properties of CNT/TiO2 filmstudied in the previous work, suggest that the best level of doping is with 0.5% of CNTs. FTIR (Fourier transform infrared spectroscopy) measurements conducted on a series of pristine and doped samples clearly indicate the absence of change in allotropic species of TiO2, while AFM (atomic force microscope) analysis indicates that the sample roughness strongly changes with doping, preventing the dye adsorption. Finally, measurements of cell efficiency indicate an increase of 5% in cells with 0.5% of CNT doping and a decrease for greater values. 展开更多
关键词 Graetzel cells dye adsorption titanium dioxide carbon nanotube doping.
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Influence of monovalent alkaline metal cations on binder-free nano-zeolite X inpara-xylene separation
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作者 Milad Rasouli Nakisa Yaghobi +2 位作者 Seyedeh Zahra Movassaghi Gilani Hossein Atashi Majid Rasouli 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第1期64-70,共7页
The adsorption process was studied for separating para-xylene from xylene mixture on modified nano-zeolite X in a breakthrough system. Nano-zeolitic adsorbent with different ratios of Si O2/Al2O3 was synthesized throu... The adsorption process was studied for separating para-xylene from xylene mixture on modified nano-zeolite X in a breakthrough system. Nano-zeolitic adsorbent with different ratios of Si O2/Al2O3 was synthesized through hydrothermal process and ion-exchanged with alkaline metal cations like lithium, sodium and potassium. The product was characterized by X-ray diffraction, scanning electron microscopy(SEM), nitrogen adsorption,transform electron microscopy(TEM) and in situ Fourier transform infrared(FTIR) spectroscopy. The influence of nano-zeolite water content and desorbent type on the selectivity of para-xylene toward other C8 aromatic isomers was studied. The optimization of adsorption process was also investigated under variable operation conditions. The isotherm for each isomer of C8 aromatics and the desorbents possess the adsorption characteristics of Langmuir type. The selectivity factor of para-xylene relative to each of meta-xylene, ortho-xylene and ethylbenzene under the optimum conditions obtained to be 5.36, 2.43 and 3.22, in the order given. 展开更多
关键词 Nano-zeolite X ADSORPTION C8aromatics ISOTHERM
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SH-wavefield simulation for a laterally heterogeneous whole-Earth model using the pseudospectral method 被引量:7
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作者 WANG YanBin TAKENAKA Hiroshi 《Science China Earth Sciences》 SCIE EI CAS 2011年第12期1940-1947,共8页
We present a scheme to simulate SH-wave propagation in a whole-Earth model with arbitrary lateral heterogeneities employing the Fourier pseudospectral method. Wave equations are defined in two-dimensional cylindrical ... We present a scheme to simulate SH-wave propagation in a whole-Earth model with arbitrary lateral heterogeneities employing the Fourier pseudospectral method. Wave equations are defined in two-dimensional cylindrical coordinates and the model is taken through a great circle of the Earth. Spatial derivatives in the wave equations are calculated in the wavenumber domain by multiplication, and the transformation between spatial and wavenumber domains is performed via fast Fourier transformation. Because of the high accuracy and high speed of the Fourier pseudospectral method, the scheme enables us to calculate a short-wavelength global SH-wavefield with accurate waveforms and arrival times for models with heterogeneities that can be approximated as azimuthally symmetric. Comparing with two-dimensional simulation methods based on an axisymmetric model, implementing the seismic source in the present scheme is more convenient. We calculated the global SH-wavefield for the preliminary reference Earth model to identify the generation, reflection and refraction of various seismic phases propagating in the Earth. Applications to a heterogeneous global model with low-velocity perturbation above the core-mantle boundary were conducted to analyze the effect of lateral heterogeneity on global SH-wave propagation. 展开更多
关键词 wave propagation computational seismology pseudospectral method global seismology core-mantle boundary
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