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Science & Technology Review CONTENTS |
Vol.25 No.18 2007 (Sum No. 240) |
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This issue published on 25. Sep., 2007 |
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Forward |
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1 Where is the Solution for Problems Related to Three Fs (Farmers, Farmlands, Farming)?
SHI Yuanchun |
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News Round |
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7 The Butterfly in Amazon Rainforest Flaps Its Wings
SU Qing |
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Suggest |
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8 Encouraging Prospecting for Shallow Buried Ore, Coordinating Economic Development of the Western Region, etc. |
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Articles |
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17 Experimental Study on Frequency Doubling of Femtosecond Pulses
LIN Xiaoxuan, CHEN Liming, LI Yutong, et al.
Abstract: This paper studies the frequency doubling of femtosecond laser pulses with a wavelength of 790 nm using a 2 mm thick KDP crystal. The energy conversion efficiency is better than 40% after the energy and chirp of the fundamental harmonic are optimized. Moreover, the frequency doubling is analyzed as a function of laser pulse frequency chirp. It is found that the frequency doubling conversion efficiency reaches a maximum when there is no frequency chirp; for the same grating position, the frequency conversion efficiency is better by using positively chirped fundamental laser pulses than by using negatively chirped pulses.
Key Words: nonlinear physics; femtosecond laser pulses; frequency doubling
CLC Number: O437 Document Code: A Article ID: 1000-7857(2007)18-0017-04 |
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21 Investigation of the Chord Wise Distribution of Temperature in Dielectric Barrier-Discharge Plasmas
LI Hanming, LI Yingjun, MAO Lingtao, et al.
Abstract: The heat exchange is accompanied by the formation of the dielectric barrier discharge plasma. As the power with high amplitude and frequency repeatedly ionizes the air, the chord wise distribution of the temperature in the interactive region is an important indicator. Using the infrared imager, we investigate the influencing factors of the chord wise distribution of the temperature in the interactive region and the heating and cooling processes of the plasma are measured too. A Gaussian distribution of the chord wise distribution is observed experimentally, which provides a promising way to increase the induced air flow to realize the flow control with the dielectric barrier discharge plasma.
Key Words: dielectric barrier discharge; infrared imager; distribution of the temperature; heat exchange
CLC Numbers: O531, O551.2 Document Code: A Article ID: 1000-7857(2007)18-0021-06 |
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27 Research on the Box Dimension of Blasting Seismic Wave Based on the Fractal Theory
LONG Yuan, YAN Junwei, LOU Jianwu, et al.
Abstract: Based on the characteristics of the blasting seismic wave and the fractal theory, this paper proposes a fractal box dimension model. By using the test data of the deep-hole blasting experiments carried out on a rock site, the fractal box dimension values D of blasting seismic signals is calculated according to this model. An analysis on the relationship between box dimension values D and the medium characteristics shows that the fractal box dimension value D of the blasting seismic wave can be used as a new important parameter to describe the blasting seismic wave. It reflects some important information concerning the properties of rock, the medium of the blasting seismic wave.
Key Words: mechanics of explosion; fractal theory; blasting seismic wave; box dimension model; no-dimensional parameter
CLC Numbers: O389, TD235.1 Document Code: A Article ID: 1000-7857(2007)18-0027-05 |
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32 Human Serum Albumin and A Rat's Model for D-Galactosamine/Lipopolysaccharide Induced Acute-on-Chronic Liver Failure
LIU Xuhua, CHEN Yu, ZHANG Jing, et al.
Abstract: There was no report on experimental model for acute-on-chronic liver failure, which is most commonly found in China. Immunological hepatic fibrosis was induced by human serum albumin in Wistar rats, then D-galactosamine/lipopolysaccharide was administered. 90% of rats died from acute liver failure after administration of D-galactosamine/lipopolysaccharide, with mean survival time of (16.1¡À3.7) hours. The kinetic changes of AST and TBil were compatible with massive necrosis of hepatocytes. Histopathological studies revealed massive or submassive necrosis in regenerative nodules, with fibrosis septa being kept intact. Plasma level of TNF-¦Á was significantly increased 8 hours after administration of D-galactosamine /lipopolysaccharide, in association with apoptosis shown by TUNEL, while the profile of plasma IL-10 level was consistent with immunosuppression as seen in patients with acute-on-chronic liver failure. Animal model for acute-on-chronic liver failure can be established by treating human serum albumin-induced rat's cirrhosis with D-galactosamine/lipopolysaccharide. This model duplicated partly pathophysiological process as seen in acute liver failure developed on the chronic liver disease. TNF-¦Á-mediated liver cell apoptosis plays a very important role in the pathogenesis.
Key Words: acute-on-chronic liver failure; animal model; lipopolysaccharide; D-galactosamine
CLC Numbers: R575.3, R332 Document Code: A Article ID: 1000-7857(2007)18-0032-06 |
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38 Residual-Based Modal Analysis Based on Phase Measurement System
ZHANG Xiuying, ZHANG Chuanmin, ZHANG Chuanli, et al.
Abstract: In this paper, GPS-based phase measurement system is introduced including the hardware and the architecture of the system based on Internet/Intranet. A new algorithm, the residual-based method, is developed to identify the system modes. The measurement system has been applied in Australian Network and have successfully identified the oscillatory frequency and damping values of the power system. Results from the analysis show that the residual-based method is able to completely extract the oscillatory information of the system.
Key Words: modal analysis; power system oscillation; voltage angle
CLC Number: TP227 Document Code: A Article ID: 1000-7857(2007)18-0038-04 |
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42 Experimental Research and Application of Skewed Gas Flow Technology
HE Jian, ZHANG Yuhai, XU Guosheng
Abstract: Skewed gas flow technology (SGFT), which is less researched at home, is one of the new technologies for improving ESP performances, and applied into actual ESP by foreign experts which obtained a significantly achievement. This paper studies the feasibility of SGFT by analyzing the particle distribution and on this basis the optimal gas distribution is gained by utilizing properly adjusting scheme. At the end of this paper, the results of SGFT used in industry programs are analyzed.
Key Words: skewed gas flow technology; particle distribution analyzing; ESP; renovation and improving
CLC Number: TM925.31 Document Code: A Article ID: 1000-7857(2007)18-0042-05 |
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47 Effects of Chemical Additives on Compressive Strength of Fly Ash-Desulphogypsum
YUAN Yongtao, WANG Fangqun, QI Liqiang, et al.
Abstract: In order to explore the comprehensive disposal and use of two kinds of solid waste-fly ash and desulphogypsum, in power plant, the ratios of fly ash/desulphogypsum and water/solid between fly ash and desulphogypsum, with respect to the two major solid wastes in coal-fired power plants, are studied by experiments, while they are being naturally cured in the air and the influences of chemical additives such as sulfates, lime, NaOH and acid exciting agents on cementitious material strength are analyzed. The results indicate that the optimum reaction mass ratio between fly ash and desulphogypsum is 3:2; the compressive strength of corresponding cementitious material is the highest with 1% K2SO4, 1% lime, 3% NaOH, 10% HCl solution being, respectively, added into fly ash-desulphogypsum system. And when the ratio of water/solid is 0.23, the compressive strength is the best.
Key Words: fly ash; desulphogypsum; solidification; additives; cementitious material
CLC Number: TQ177.3+9 Document Code: A Article ID: 1000-7857(2007)18-0047-05 |
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52 Design of Electrostatic Precipitator for Orimulsion-fired Boiler
FU Bohe
Abstract: Orimulsion is an emulsified fuel, consisting of Orinoco natural bitumen (70%), fresh water (30%) and a small amount of surfactant. Compared with heavy oil, it contains higher amounts of sulfur, water, vanadium and ash. It is still in a preliminary stage in using orimulsion and studying its environment in China. This paper discusses the design principle of the electrostatic precipitator for orimulsion-fired boiler, which can serve as a reference for power plant in using heavy oil and orimulsion.
Key Words: Orimulsion; electrostatic precipitator
CLC Number: TM925.31 Document Code: A Article ID: 1000-7857(2007)18-0052-04 |
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56 Cellular Automata Simulation Study on Complexity of the Stock Exchange Market
YANG Fan, XU Shiying
Abstract: With Shanghai stock exchange market as a research object, this paper studies the complexity of the stock exchange market using the cellular automata theory and model. With the fractal theory as a tool, the R/S method is used to compare the real and the simulated data, which verifies the validity of the simulation. In the CA model, with different initial values and rules, we can improve the study on complexity in the stork exchange market.
Key Words: R/S method; fractal dimension; cellular automata; complexity
CLC Number: N941 Document Code: A Article ID: 1000-7857(2007)18-0056-07 |
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63 Study on the Viticultural Climatic Zoning in China (I)
LI Hua, WANG Hua, FANG Yulin, et al.
Abstract: This paper analyzes the climatic index systems used in the viticultural zoning and the climatic characteristics in China. It is shown that all climatic zoning index systems are based on the Mediterranean and para-Mediterranean climatic conditions, therefore, are not necessarily suitable for the climate conditions in China, which are dominant with continental features. The principles in the viticultural climatic zoning in China are proposed based on the conditions demanded by the growth of grapevines and related problems are discussed.
Key Words: grapevine; climatic zoning; viticulture
CLC Number: S663.1 Document Code: A Article ID: 1000-7857(2007)18-0063-06 |
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Reviews |
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69 Application of Corona-induced Non-thermal Plasma in Gas Cleaning
YAN Keping |
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75 Effects of Environmental Chemicals on Biomarkers Using Free-living Nematode
WANG Shuozhi, RU Shaoguo, DU Enzai |
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81 Notes on Reviews in Chinese Science Abstracts(Chinese Edition) |
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Science Reports |
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82 Technological Innovation and the Sustainable Development of the Western Region |
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Commentary |
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85 From Information Economy to Bio-Economy: The Change and Contant
FENG Ying, WU Yishan |
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86 New Humanity of "the Father of Science History" Revisited
DONG Yuyu |
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87 Books Appraisal |
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Editor-in-chief's Thoughts |
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89 How to Pound the Foundation of Postgraduates Successful Research Career (X)
FENG Changgen |
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Special Columns |
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6 Cover Story |
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9 Voice of Scientific Communit |
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10 Half-month News Briefs |
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12 International Journal Highlights |
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13 Domestic Journal Highlights |
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14 Scientific Community Briefs |
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16 Guidance for Contributors to Science and Technology Review |
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84 Events |
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88 Readers'Letters |
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90 Entertainment |
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92 Digest of Chinese Newspapers and Journals |
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93 Career |
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95 Global Jobs |
