[an error occurred while processing this directive]

Table of Content

    20 September 2011, Volume 47 Issue 5
    Ecological Risk Assessment of Natural Disasters in China
    XU Xuegong,YAN Lei,XU Lifen,LU Yaling,MA Luyi
    2011, 47(5):  901-908. 
    Asbtract ( )   PDF (7765KB) ( )  
    Related Articles | Metrics
    The authors explore an approach on large scale of regional ecological risk assessment, and implement the integrated assessment of China, so as to provide scientific support for eco-system risk recognition and risk prevention. Select the 10 natural disasters as ecological risk sources, 22 species of the ecosystem as risk receptors and consider eco-environmental vulnerability. The integrated ecological risk assessment and mapping are conducted, on the basis of evaluating ecological risk by individual disaster and overlaying various risk evaluation by GIS. The result shows that the high, medium risk level of eco-system areas account for 45% of China’s territory. The environmental protection and risk prevention are very important and need to go a long way. It is imperative to establish adaptive disaster reduction and risk prevention mechanisms, make rational use and conservation for the forests, grassland, farmland, wetlands and other ecosystems.
    Psychological Typhoon Eye Effect in the Wenchuan Earthquake
    XIE Jiaqiu,XIE Xiaofei,GAN Yiqun
    2011, 47(5):  944-952. 
    Asbtract ( )   PDF (741KB) ( )  
    Related Articles | Metrics
    This study measured the risk perception, risk behavior propensity, and anxiety state of 494 residents in Hanwang, Panzhihua, and Beijing, which were impacted to different extent by the 5.12 Wenchuan Earthquake. The results confirmed the hypothesis of a Psychological Typhoon Eye Effect in terms of risk perception of tremors and risk behavior propensity, but revealed a reversed effect with regard to state anxiety. In addition, residents from Panzhihua, which is located in the edge zone of earthquake tremors, showed the most conflicting psychological reactions. The final part discusses the situational factors for Psychological Typhoon Eye Effect and Edge Zone Effect.
    Design Optimization and Implementation of Carrier Tracking Loop for High Sensitivity GPS Receivers
    WU Lingjuan,CUI Yingying,LU Weijun,YU Dunshan
    2011, 47(5):  783-788. 
    Asbtract ( )   PDF (506KB) ( )  
    Related Articles | Metrics
    This paper presents the design, optimization and implementation of GPS carrier tracking loop based on high sensitivity GPS base band signal processor research topic. The phase detector, loop error sources and loop parameters are first optimized to improve the tracking sensitivity and then the phase lock loop assisted by frequency lock loop circuit structure is applied. The circuit is optimized and timing-sharing technology is used for the modules including several multipliers and dividers to reduce resource consumption and save chip area. The authors implement the designed GPS carrier tracking loop in Verilog and complete the logic and functional simulation in Modelsim with RTL level code. The FPGA board verification platform is established and the performance test is carried out using GPS L1 band signal source. The test result shows that the tracking sensitivity can reach 25 dB-Hz and chip area of the single channel carrier tracking loop is 425555μm2 in SMIC 0.18μm technology using Design Complier.
    Synthesis and Characterization of Gold Nanoparticles with Various Diameters
    ZHENG Haixia,HUANG Boneng,HU Junman,GONG Yan
    2011, 47(5):  777-782. 
    Asbtract ( )   PDF (12060KB) ( )  
    Related Articles | Metrics
    Gold nanoparticles with various diameters were synthesized by chemical reduction. UV-Vis spectroscopy and transmission electron microscopy (TEM) were used to characterize the morphology and the size of the prepared Au nanoparticles. The effects of factors, such as the type of the reducing agent, the amount of the reducing reagent, reagent adding order and reaction temperature on the stability, radius, morphology and dispersion of Au nanoparticles were studied. The results show that the size of Au nanoparticles prepared with Na3C6H5O7 as a reductant was within the range of 15~20 nm, and the size of Au nanoparticles prepared with NaBH4 as a reducing agent was within the range of 3~10 nm. The optimum molar ratio of Na3C6H5O7 and HAuCl4 was 1.5:1. The gold nanoparticles prepared after adding HAuCl4 to the hot mixture of Na3C6H5O7 and poly vingl pyrrolidone (PVP) solution were better dispersed, smaller in size and more uniform, compared with that prepared after adding Na3C6H5O7 to the hot mixture of HAuCl4 and PVP solution.
    Identification of Topic Sentence about Key Event in Chinese News
    WANG Wei,ZHAO Dongyan,ZHAO Wei
    2011, 47(5):  789-796. 
    Asbtract ( )   PDF (571KB) ( )  
    Related Articles | Metrics
    The authors propose an approach to extract topic sentences that describe key event from a news article. Considering the special structure of news articles, the relations between news articles and key events reported in them is studied, as well as the characteristics of a news headline in three aspects: information, form and language. A novel method based on the information aspect of a headline is used to extract a topic sentence which contains the key event information from a news story. The method first classifies a news headline as informative or non-informative, and then considers text and semantic features of a sentence, such as word frequency, sentence length, location in the text and word co-concurrency with the headline, to evaluate the importance for each sentence and select the most important one as the topic sentence. Experiment results show that this method can identify a topic sentence accurately and the proposed approach makes a good preparation for event information extraction.
    Estimation of the Soil Moisture Using FY-3A/MWRI Data over Semiarid Areas
    PENG Lichun,LI Wanbiao,LIU Huizhi
    2011, 47(5):  797-804. 
    Asbtract ( )   PDF (535KB) ( )  
    Related Articles | Metrics
    In order to monitor the range and extent of drought and resolve the serious problems of the semi-arid regions, a soil moisture retrieval method by satellite microwave remote sensing is proposed. The relation of microwave brightness temperature and surface soil moisture was simulated by surface and atmosphere microwave radiative transfer models. The soil moisture retrieval algorithm in the logarithm-cubic form was established. By using the data of the microwave radiation imager aboard the FY-3A polar orbiting meteorological satellite and the retrieval algorithm, the soil moisture was derived for the farmland and the grassland in Tongyu of Jilin. The result shows that the retrieval soil moisture is in good agreement with the ground-based observations. The root mean square error is 0.003 cm3/cm3 for the farmland, and 0.005 cm3/cm3 for grassland. The method can be applied to the future FY-3B satellite that is possible to derive more information. With the improved radiation transfer model in the future, the radiation characteristics of the various grounds will be obtained. The regional moisture study will be carried on in the future.
    Analysis of Ozone Vertical Distribution in Shanghai Area
    PENG Li,GAO Wei,GENG Fuhai,RAN Liang,ZHOU Hourong
    2011, 47(5):  805-811. 
    Asbtract ( )   PDF (1393KB) ( )  
    Related Articles | Metrics
    The observations of ozone sounding at Shanghai Baoshan National Climate Stations during May 2007 and December 2009 are analyzed. The results show that ozone vertical distribution is mainly influenced by photochemistry and dynamic transport. Ozone distribution in the boundary layer and the middle and upper stratosphere is apparently influenced by photochemistry. In the boundary layer, ozone concentration gradient varies positively. Influencing factors such as temperature, radiation and vapor, lead to a seasonal variation of highest ozone in the summer and lowest ozone in the winter. Above 26 km, photochemical processes lead to the highest ozone concentrations in the middle and upper stratosphere in the summer, vice versa in the winter. Dynamic transport significantly influences ozone level in upper troposphere and lower stratosphere, about 10-17 km. Ozone concentration is highest in spring due to the process of stratosphere-troposphere exchange.
    Case Analysis and Econometric Model of Resource and Environmental Impact of Tourism Industry on Destination
    YI Zhibin,XU Hong
    2011, 47(5):  863-867. 
    Asbtract ( )   PDF (454KB) ( )  
    Related Articles | Metrics
    The authors try to establish the econometric model of environmental impact of tourism industry on destination from the six facets of tourism based on the theory of environmental economy, and take the accommodation in Beijing as example, estimate the resource and environmental impact of visitors’ accommodation. The resource and environmental cost of visitors accommodation is 5.464×108 Yuan elementarily in 2008. Considering on the water and energy consumption per unit GDP value, the tourism industry belongs to the saving water and energy industry relative to others industries.
    3D Modeling and Analysis of Natural Foundation Bearing Capacity Based on Kriging Method
    QIAO Jinhai,PAN Mao,JIN Yi,ZHAO Zengyu
    2011, 47(5):  812-818. 
    Asbtract ( )   PDF (1844KB) ( )  
    Related Articles | Metrics
    The authors introduce the basic principles of Kriging and the simulation of variogram and elaborate the method in details, including several aspects: formation of the block model, collection and exploration of experimental data, semivariogram analysis, interpolation etc. The authors present a method which integrates 3D solid modeling with Kriging. The method can provide important decision support aid for urban development planning and construction by 3D visualization. Finally, the practical effect of the method is shown in a case study, and the sampling area locates in Beijing and 887 samples are adopted. The anthors present the analysis results of the model, verify the accuracy of the result, and carry on comparative analysis with 2D model. The results demonstrate the validity of method presented base on 3D GIS and Kriging, and 3D visualization makes it convenient to make decision for professionals.
    Key Technologies of Prediction and Display of Deformation Field Induced by Underground Construction
    TIAN Tian,PAN Mao,HAN Xuan,CONG Weiqing,ZHANG Fang,ZHANG Jie
    2011, 47(5):  819-824. 
    Asbtract ( )   PDF (1553KB) ( )  
    Related Articles | Metrics
    Basing on the “3D Engineering Investigation Information System”, a “3D Underground Construction Deformation Display System” is developed. Empirical methods were used to predict the deformation of strata and buildings in the system. 3D regular grid model and triangulated irregular network (TIN) model were used for the 3D deformation field visualization. For the TIN model, the adaptive TIN keep-geometry refinement algorithm were developed. This algorithm can depict the deformation field in higher resolution without remarkable data size increase. Therefore the modeling and analysis of very large areas become possible.
    The Third Series of Cambrian Oolitic Limestones and Their Sedimentary Environment in Beijing, Tianjin, Shanxi and Hebei Provinces, North China
    ZHAO Pengyun,LIU Bo,QIN Shan
    2011, 47(5):  825-830. 
    Asbtract ( )   PDF (4134KB) ( )  
    Related Articles | Metrics
    The study area, geographically including Beijing, Tianjin, Shanxi and Hebei Provinces, is the main part of the North China Plate. Based on the study of outcrop and thin section observation, the distribution pattern of oolitic limestone and its ooid characteristics are presented. Olitic limestones were widely distributed in the area during the Third Series of Cambrian. Generally, the oolitic limestone elevates in strata gradually from east to west, which indicates that the oolitic limestone is diachronous. Huge oolitic shoals distribute along a western ward bulging belt from north to south, and mainly are composed of concentric ooids. In west of the belt, the thickness of the oolitic limestone decreases rapidly, and the oolitic limestone mainly is composed of radial ooids. In east of the belt, the oolitic limestone thins gradually, with majority grains of concentric ooids. The marine transgression during the Third Epoch of Cambrian took place from east to west on the North China Plate. In this background, the inner ramp ooid shoals developed in the central belt of the study area, with open sea in the east and shoal back tidal flat in the west.
    Effect of Carbonate Rock to Development of Structural Fracture in the Area of Keping, Xinjiang, China
    ZHANG Peng,HOU Guiting,PAN Wenqing,JU Yan,ZHANG Qinglian,LI Le,SHU Wulin
    2011, 47(5):  831-836. 
    Asbtract ( )   PDF (2564KB) ( )  
    Related Articles | Metrics
    Four sections of dolomite, grainstone, micritic limestone and granulir micritic limestone in Dawangou of Keping area are selected, and their structural fractures are statistically analyzed. The results of fracture density measurements show that the value of the fracture density from big to small is dolomite, grainstone, micritic limestone and granulir micritic limestone, which means in the same tectonic setting dolomite is easier to produce structural fracture. Also, the purer and the bigger granules the carbonate have, for example limestone, the more difficulty to produce structural fracture. The relationship between the structural fracture and the rock mechanics parameters is discussed.
    AVO Template of Sandstone Reservoir under Formation Condition
    HE Tao,SHI Ge,ZOU Changchun,REN Keying,PEI Fagen
    2011, 47(5):  837-844. 
    Asbtract ( )   PDF (1448KB) ( )  
    Related Articles | Metrics
    The reservoir sandstone core samples from W3 formation of WXS depression were measured for density, porosity and acoustic velocity under pressure and temperature of formation condition in laboratory. A method based on core result and rock physics model was proposed to produce an advanced AVO response template capably showing integrated information of reservoir character (porosity and thickness) and saturation fluid. This method used the sandstone porosity as the key factor to construct the rock physics model based on the linear relationships of porosity-density and porosity-impedances in dry condition. Using Gassmann fluid replacement technique, the forwarding modeling results of AVO responses for different reservoir conditions were obtained, and then the AVO template was made by analyzing the distribution and shape characteristics of AVO clusters on intercept-gradient crossplots. Through this template the porosity, thickness and fluid type of reservoir could be estimated directly, and thus the non-uniqueness of AVO inversion due to complex geology was greatly reduced and the accuracy of direct hydrocarbon prediction could also be improved.
    Anciant Geomorphological Environmental Evolution of the Ancient Jicheng Area in Beijing: A Case of the Geotechnical Profile in the Construction Field of Guangyi Building
    YUE Shengyang,MIAO Shui,XU Haipeng
    2011, 47(5):  845-852. 
    Asbtract ( )   PDF (4682KB) ( )  
    Related Articles | Metrics
    The Guanganmen area is the locality of the ancient Jicheng city (the earliest city site in Beijing). Based on the geomorphological analysis and the several kinds of experiments for the samples collected from the geotechnical profile in the construction site of Guangyi Building in Guanganmen area, the reconstructions of palaeogeomology in this area were conducted. The results show that the location of the ancient Jicheng city was just the highland, which developed since the Holocene, beside the river, where the channel of Yongding River has been passed through about 22000 years ago. The climate in this area has changed from the cool and wet environment (sparse-wood grassland was developed) and the following arid environment (grassland vegetation was developed) in the late Late-Pleistocene to the warm and wet environment (sparse-wood grassland was developed) and the following cool and wet conditions (meadow vegetation was developed) during the Holocene.
    Comprehensive Evaluation of Land Use Ecosystem Service Value in Beijing
    TANG Xiumei,CHEN Baiming,LU Qingbin
    2011, 47(5):  853-862. 
    Asbtract ( )   PDF (2557KB) ( )  
    Related Articles | Metrics
    A comprehensive evaluation of land use ecosystem service value is brought out. Based on the evaluation, the land classification of ecological function importance is explored. Firstly, the main land use types in Beijing are determined with 9 first types and 15 sub-types, then the basic ecosystem service value of each type is determined. Secondly, the factors including natural, location and humanistic conditions are chosen to evaluate the ecological environment and divide Beijing into 4 ecological zones. Thirdly, the land use ecosystem service value is corrected by the ecological environment indexes of each ecological zone and the land classification of ecological function importance is figured out with the clustering method by their ecosystem service value. In the end, the comprehensive evaluation method is applied to the current land utilization maps of Beijing in 1993, 2001 and 2007, and the distribution maps of ecosystem service value in per unit area and land classification of ecological function importance are obtained, so the changing situation of ecosystem service value and each type of land classification of ecological function importance in Beijing are analyzed according to the result. It shows that, the total ecosystem service value of Beijing decreases from 1993 to 2007 and that of ecological zone decreases except one zone. The grade of land classification of ecological function importance is decreasing from central city to suburb and the grade in northwest is higher than that of southeast. The area of the first class, the second class and the sixth class increases, while the area of the third class, the fourth class and the fifth class decreases from 1993 to 2007.
    Key Components and Modeling Framework for Intelligent Watershed Management (IWM)
    ZOU Rui,LIU Yong,YAN Xiaopin,GUO Huaicheng
    2011, 47(5):  868-874. 
    Asbtract ( )   PDF (481KB) ( )  
    Related Articles | Metrics
    A new watershed management module, Intelligent Watershed Management (IWM), was proposed. The decision need for watershed management was analyzed before the conception and components of IWM were formulated. The idea of IWM comes from the principles of bionics and imitates the process of human decisions. The IWM is significantly differing from traditional watershed management, which includes three main steps, i.e. watershed information inquiring, input-output response modeling at the watershed scale, and optimized decision making. Four key issues of IWM were identified, including the management goal, suitable models, non-linear responses and computational requirement, and the uncertainties in the watershed system. The modeling framework of IWM was developed and some new algorithms were proposed, such as Risk Explicit Interval Linear Programming (REILP) and Nonlinearity-Interval Mapping Scheme (NIMS) for simulation-optimization analysis. Some cases were demonstrated for the efficiency of the proposed models.
    Grassland Ecological Vulnerability Assessment of Mu Us Desert in Recent 50 Years: A Case Study of Wushen Banner
    JIN Yi,MENG Jijun,HUANG Jiao
    2011, 47(5):  909-915. 
    Asbtract ( )   PDF (3778KB) ( )  
    Related Articles | Metrics
    Mu Us Desert is one the most sensitive and vulnerable areas in China. Based on spatial analysis tool of GIS, this study performs a dynamic ecological vulnerability assessment of Wushen Banner in 1960s, 1978, 1988, 2000 and 2008 by using the ecological vulnerability evaluation model established though analytic hierarchy process. The conclusion is that the majority parts of Wushen Banner belongs to middle and low vulnerable area. The grassland ecological vulnerability experienced decrease, increase and decrease in recent 50 years, and the grassland ecological vulnerability of southern Wushen Banner is higher than the northern area. The changing process is caused by two reasons. One is that Wushen Banner ecosystem locates in the semiarid and heavy sand-wind area, another is the ecological interferences which include both natural and social aspects, especially by fluctuation of aridity, population growth and extensive ranching. Finally, the authors give suggestions about how to protect and utilize the grassland resource based on the evaluation result.
    Emission Inventory Prediction of HCFC-141b in China
    YAN Huanghuang,ZHANG Jianbo
    2011, 47(5):  875-881. 
    Asbtract ( )   PDF (555KB) ( )  
    Related Articles | Metrics
    Emission inventory of HCFC-141b in China was established based on the IPCC Guidelines for National Greenhouse Gas Inventories (2006). Constitution and trend of HCFC-141b emission was analyzed. The product retire emission, which considered to be the largest part of emission, accounts for 48.7% of the total; under Montreal Protocol Phaseout Schedule (MPPS) and Accelerated Phaseout Schedule (APS) scenarios, total ODP emission reduction would be 7.30×104 tons and 7.46×104 tons ODP and GHG emission reduction would be 4.7317×108 tons and 4.8381×108 tons CO2-eq respectively during 2010-2030; compared to the MPPS scenario, the APS scenario result in additional 3.815×107 tons CO2-eq GHG emission reduction during HCFC-141b emission period and most of the reduction comes from refrigerator, water heater insulation and panel sub-sector. China makes great contribution on global GHGs reduction during the implementation of Montreal Protocol.
    Uncertainty Analysis of Integrated Ecological Risk Assessment of China
    MA Luyi,XU Xuegong,XU Lifen
    2011, 47(5):  893-900. 
    Asbtract ( )   PDF (5429KB) ( )  
    Related Articles | Metrics
    On the basis of the integrated ecological risk assessment of China, this research chooses the risk sources data as the main source of uncertainties to analyze their impact to the risk value calculation and the sensitivities of the risk value to them. Monte Carlo smulation method is used to perform these proprieties for each pixel throughout the country with the special scale of 10 km×10 km. In the simulation progress for each pixel, the uncertainty is set firstly, and then the probability distribution of the risk source levels are computed according to their frequency statistics for at least last 50 years. At last, the simulation of risk value is carried out reference to the equitation of integrated ecological risk assessment. Meanwhile, the sensitivities of the risk value to all risk sources are got in term of Spearman rank correlation coefficients, the variance contribution of which can be used to figure out the sensitivity structure of all risk sources. The uncertainties are set as 50% and 25% to indicate high uncertainty and low uncertainty respectively, and the simulation times is set as 10000 for each pixel. The results show that 1) the simulated mean risk values are close to the calculated risk values, the ratio of them for all pixels are concentrated in 0.80?1.20 with either high or low uncertainty, and 0.95?1.05 for low uncertainty, although some differences exist between different hazard regions; 2) the simulated maximum risk values are also close to the calculated risk values, which are mostly less than one and a half of the calculated, except for the Qinghai-Tibet region; 3) for the whole country, three main risk sources that the risk value most sensitive to are droughts, floods and landslides/debris flows.
    On Complex System Model of Thinking and Design of a New Generation of Expert System
    SHE Zhensu,NI Zhiyong
    2011, 47(5):  960-968. 
    Asbtract ( )   PDF (1387KB) ( )  
    Related Articles | Metrics
    From a complex system perspective, the authors report a conceptual model of thinking. In this model, the knowledge forms a complex network, in which concepts form nodes, conceptual relationships form links, and propositions form network circuits. It suggests that a thinking process such as deductive reasoning corresponds to a set of network dynamical events with competing activations of network circuits under an optimization function. This conceptual model leads to a design for the next generation of expert system.
    Identification and Application of Seasonality Parameters of Crop Growing Season in Northeast China Based on NDVI Time Series Data
    LI Zhengguo,TANG Huajun,YANG Peng,ZHOU Qingbo,WANG Yanglin,WU Wengbin,YIN He,ZHANG Li
    2011, 47(5):  882-892. 
    Asbtract ( )   PDF (3348KB) ( )  
    Related Articles | Metrics
    The authors investigated spatio-temporal patterns of seasonality parameters of crop growing season in Northeast China, by using the SPOT/VGT NDVI ten day composed time-series data collected from 1998 to 2009. First, to minimize the effects of anomalous values caused by atmospheric haze and cloud contamination, the software TIMESAT was used to generate smooth time series of NDVI based on an asymmetric Gaussian function; second, the seasonality parameters, such as the start date, the end date, the peak date, and length of the growing season, were defined and extracted from the smoothed NVDI time-series dataset; third, each of the extracted parameters and the observed agricultural phenophases (including the stages of seedling, heading and maturity for harvest, length of growth period) were compared and validated by using a scatter plot, respectively; finally, the temporal trends and spatial patterns of the major crop seasonality parameters in Northeast China were illustrated and analyzed over the past 10 years. The results show that the growth process of major crops can be discriminated to a certain extent from the temporal trend of observed crop phenological characteristics. Obvious linear correlations can be found between the extracted seasonality parameters and the observed crop phenophases, which indicates that spatio-temporal variations of crop phenophase can be expressed in details by utilizing the extracted parameters from the smoothed NDVI time series. Meanwhile, all these grid-based crop phenophases can be used as data alternative for studying the spatio-temporal responses of crop growth process caused from fluctuation in external environmental conditions, such as air temperature, precipitation and daylight hours, etc.
    VOCs Fluxes Analysis Based on Micrometeorological Methods over Litchi Plantation in the Pearl River Delta, China
    GAO Xiang,ZHANG Hongsheng,CAI Xuhui,SONG Yu,KANG Ling
    2011, 47(5):  916-922. 
    Asbtract ( )   PDF (652KB) ( )  
    Related Articles | Metrics
    Observations of VOCs concentration were conducted at a litchi plantation in the Pearl River Delta in July 2008 and February-March 2009 respectively. VOCs fluxes were estimated based on the relationship of flux-gradient and REA method using the VOCs concentration data. Statistical evidence indicates that the major emission matter is isoprene with a typical daytime mean flux 0.932 nmol/(m2?s) in the growing season over the litchi plantation. While in the non growing season, the flux is negligible. This study provides a reliable reference not only for emission rates for litchi and manmade plantation, but also for usage of micrometeorological methods to measure VOCs fluxes.
    Impact of Anaerobic Phenanthrene Biodegradation on Bacterial and Archaeal Communities
    ZHANG Shuying,XIE Shuguang
    2011, 47(5):  923-928. 
    Asbtract ( )   PDF (423KB) ( )  
    Related Articles | Metrics
    Terminal restriction fragment length polymorphism (TRFLP) was used to investigate the change of bacterial and archaeal communities in leachate-contaminated aquifer in response to anaerobic phenanthrene biodegradation. Results show that a great change in bacterial community occurred with phenanthrene biodegradation. The ribotype and Shannon-Weiner index increase from 15 to 23, and 2.39 to 2.88 respectively. However, archaeal community only shows an insignificant change with phenanthrene biodegradation, and ribotype and Shannon-Weiner index vary slightly.
    A Preliminary Study on the Characteristics of β-Glucosidase from a Newly Isolated Aspergillus fumigates
    LEI Jing,HUANG Wen,LI Tianhong
    2011, 47(5):  929-932. 
    Asbtract ( )   PDF (1973KB) ( )  
    Related Articles | Metrics
    A strain of Aspergillus fumigates with high activity towards Dioscorea zingiberensis saponins was isolated, and the characteristics of its β-glucosidase were studied preliminarily. As shown in the results, the β-glucosidase from Aspergillus fumigates which effectively produced diosgenin from saponins, exhibited the high level of activity and stablity at high temperature. At 65℃ and pH6.0, the β-Glucosidase activity of Aspergillus fumigates was 4.1 U/mg, and it retained 77% of its original activity for 48 hours with 1.5 mol/L ammonium sulfate. The β-Glucosidase of this Aspergillus fumigates hydrolyzed the D-glucose at the C-3position in trillin to yield saponin, and the transformation ratio was 56% within 24 hours.
    Research on Regional Ecological Risk Assessment: A Case Study of Ordos in Inner Mongolia
    MENG Jijun,ZHOU Ting,LIU Yang
    2011, 47(5):  935-943. 
    Asbtract ( )   PDF (4266KB) ( )  
    Related Articles | Metrics
    A conceptual model of ecological risk assessment is built, which includes the following procedures: to determine the objectives of risk management, to analyze risk probability, to choose appropriate assessment methods, to characterize assessment results, and to make risk management. Ordos, the study area, is located in the farming-grazing transitional zone of northern China. On the basis of Landsat TM images, historical records, survey data and socio-economic statistical data, the authors make the regional ecological risk assessment of Ordos in 2000 and 2008 using the RS, GIS and SPSS. The stressors such as drought, flooding, pollution, strong wind, sandstorm, desertification and soil erosion, are selected as the risk sources. Also, the index system of regional ecological risk assessment is set up. The results are presented as follows. The spatial differentiation of ecological risk level is evident in Ordos. The regions with high risk distribute in the Kubuqi Desert, Waowusu Desert, and Zhungeer and so on, which is directly related to their adverse environmental background and economic activities like large-scale mining. In 2000, the regions with moderate or high risk level mainly lie in the Zhungeer, Dalate, the Kubuqi Desert in Hangjin, and the middle, north, and southwest of Wushen. In 2008, the risk of most areas is lower. However, there are some exceptions, for example, the areas such as the middle and southwest of Dalate Banner, the northwest of Dalate Banner which lies in the Kubuqi Desert and along Yellow River, take higher risk. Dynamically, the risk degree presents a downward trend from 2000 to 2008, which is due to the implementation of various measures concerning eco-environmental construction and restoration. To be specific, the risk of grass and desert ecosystems decreases significantly, so does the farmland and forest. However, the risk of water and urban and rural ecosystems increases.
    Analysis on Why UK Advanced CCS Development and Valued Cooperation with China
    WANG Zhongcheng,SONG Bo
    2011, 47(5):  953-959. 
    Asbtract ( )   PDF (491KB) ( )  
    Related Articles | Metrics
    The authors introduce the UK’s CCS development strategy and the implementation scheme, and analyze from various angles on the background and reasons that UK actively promoted the CCS development and valued cooperation with China as well. UK has been developing CCS since the beginning of the 1990s. Especially some of energy policies such as Energy White Paper and Energy Act promulgated have laid the sound foundation furthering the development of CCS. Until now a series of activities such as CCS competition/CCS demonstration projects have been conducted. During the process of implementation, it can be found that China has been considered one of important factors in the UK’s decision on how to promote CCS technology roadmap and how to promote international cooperation. So China’s future coal market as well as the position in climate change’s politics have been and will be one of important factors that UK considered.
    Pressure Sensitivity and Its Genetic Mechanism of Igneous Rock Formations in Changshen Gas Field
    WANG Lei,SHI Yongmin,SONG Qiuguo,CHAI Zhi,QIN Xiaoshuang,LI Xiaomin,WU Wenjuan
    2011, 47(5):  969-972. 
    Asbtract ( )   PDF (1330KB) ( )  
    Related Articles | Metrics
    The core samples of igneous rock formations with low permeability and low porosity in Jilin Changshen well block are tested for their pressure sensitivity. The result shows that permeability recovery rate of these samples is not more than 11%, which indicates high pressure sensitivity of the formations. By observing core samples and comparing the result of pressure sensitivity tests with those from igneous rock core samples of other regions, it shows that the pressure sensitivity of igneous rock formations is relevant to lithology, structure, construction, development and type of porosity and fracture. Different from the unitary diagenesis of sandstone, the complex diagenesis of igneous rock leads to different pressure sensitivity in different areas. Therefore the pressure sensitivity of different igneous rock formations should be treated differently. Meanwhile, pressure sensitivity of a certain well may not be the same in different igneous layers.