Table of Content

20 November 2011, Volume 47 Issue 6

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Several Binomial Functions with Low Differential Uniformity

GUO Feiwang,ZHANG Xiyong,HAN Wenbao

2011, 47(6):  973-977. 

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Selecting the combinations of two appropriate monomial functions, the authors construct several functions with low differential uniformity, find some quadratic highly nonlinear differentially 4-uniform and cubic differentially 6-uniform binomial functions, and give a bound of nonlinearity of cubic functions by second order nonlinearity. These new functions have higher nonlinearity and lower uniformity.

Investigation on Combined Aero-Valve of Air-Breathing Gasoline-Air Pulse Denotation Engine

ZHENG Dianfeng,YANG Yiyong,WANG Jiahua

2011, 47(6):  978-982. 

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A technique of combined aero-valve to advance the air-breathing pulse detonation engine (PDE) is investigated. The combined aero-valve is composed of a blunt aero-valve and a swirling aero-valve placed in the PDE inlet in series and different combination forms can be obtained by altering their location. The results show that the combined aero-valve can produce continuous detonation waves and the optimal type is the combination with blunt aero-valve in the front and swirling aero-valve in the after. The detonation combustion performance of combined aero-valve is better than that of a single aero-valve, while the blunt aero-valve is better than the swirling valve. These results are important to develop novel aero-valve structure and the fuel atomizing-vaporizing-mixing device.

Establishment of Digital Diagnostic Templates for Malocclusion and Research of Landmark Automatic Identification

HAN Bing,XU Tianmin,LIN Jiuxiang

2011, 47(6):  983-989. 

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The purpose of this research is to provide digital diagnostic templates as references for automatic landmark identification and attempt to realize landmark automatic identification by computers. 2249 pre-treatment X-ray films of malocclusion patients were divided into 21 subtypes according to the coordinates of 60 landmarks by cluster and discriminate analysis. The total differentiate rate and leave-one-out differentiate rate were 89.1% and 85.0% respectively. 21 digital diagnostic templates were established. A new case could be classified into one subtype by discriminate functions or the characters of templates and the digital diagnostic templates could be used for diagnosis, evaluation and prognosis in orthodontic clinic. 23 landmarks of 10 new samples were identified automatically by computer using templates. The mean errors of 11 landmarks were below 2 mm, which could reach the clinical demand.

A Highly Accurate Li-Ion Battery Charger Based on Digital Controlled Source

YAN Wei,LIU Yuzhang,KANG Qi

2011, 47(6):  990-994. 

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A highly accurate Li-ion battery charging approach based on digitally controlled source by hardware was proposed. To avoid a reduced working life and a potential blast in conventional charging systems with less accurate signal-sample and control, it can synchronously detect the instant charging-states of each single cell in the whole series combinations with more stable and accurate, digitally controlled outputs. In some turbulent energy supplies from the reproducible source, the stable, accurate and universal charging system could be utilized to gain maximized efficiency of charging with minimum defaults.

Effects of Perceptual Load Related to Flight Task on Auditory ERPs

WANYAN Xiaoru,ZHUANG Damin,LU Shasha,LIU Wei

2011, 47(6):  995-1002. 

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To investigate the effects of perceptual load related to flight task on the auditory ERPs, 14 subjects participated in a flight simulation experiment, and were asked to perform the indicator-monitoring task based on different perceptual loads. Auditory probes were simultaneously sent binaurally through headphones under the oddball paradigm. Subjects were instructed to pay attention to the flight simulation task and ignore auditory probes. The auditory ERPs of mismatch negativity (MMN), N1 and P2 were recorded as the evaluation indexes of perceptual load. The results revealed that the frontal-central MMN was affected by perceptual load significantly. The MMN average amplitude was enhanced under the high perceptual load, reflecting an improvement of automation processing ability of task-irrelevant information. Furthermore, the MMN average amplitude was positively correlated with the accuracy rate of detecting abnormal information. The present study indicates that the frontal-central MMN is well sensitive to perceptual load, and it may offers effective electrophysiological reference for the perceptual load assessment in complex flight tasks. However, the results also show that the perceptual load has little effect on the auditory early components N1 and P2 as well as the temporal MMN, which manifest the complicated effects of auditory ERPs on measuring the perceptual load related to flight task to some extent.

RoBDD-Based Fine-Grained Dynamic Taint Analysis

WANG Tielei,WEI Tao,ZOU Wei

2011, 47(6):  1003-1008. 

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The bottleneck of fine-grained taint analysis is figured out. A roBDD-based fine-grained off-linetaint analysis approach is proposed. The experiment results show that the proposed approach can significantly improve the performance of fine-grained taint analysis, and reduce the memory usage.

Hardware Adaptive Copyright Protection Method for Multiple Devices of End-User

FENG Xue,YU Yinyan,TANG Zhi

2011, 47(6):  1009-1016. 

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Too restrictive digital rights management system makes that some legitimate rights of users cannot be guaranteed. Users hope the legally purchased content can be rendered on their multiple end devices and the hardware alteration of the rendering device is allowed. To solve this problem, a hardware adaptive copyright protection method for multiple devices of end-user is proposed. The method supports dynamic contents sharing, satisfies the independence between shared nodes and takes into account the copyright security. The method can solve the device independence problem in the existing hardware adaptive copyright protection mechanism, which is suitable for the devices of various types without the need for customized solutions respectively.

Calibration and Error Analysis for Multi-wavelength Sun-Photometer Observations

GAO Ling,ZHAO Chunlei,LI Chengcai,REN Tong,LI Qian

2011, 47(6):  1017-1024. 

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The theory of Langley method was used to calibrate the four multi-wavelength MICROTOPS Ⅱ sun-photometers at Lingshou in Hebei Province, and good calibration results were obtained by using least square method. Then error analysis was taken from instrument viewing angle, filter bandwidth, weather condition, gas absorption etc. The modified Langley method was adopted to the water vapor channel (936 nm). Finally, calibration results of five channels were calculated for each instrument. In order to verify the effectiveness of the calibration, the calibrated sun-photometers were used to observe the aerosol optical thickness (AOT) at Wuqing in Tianjin and Shijiazhuang in Hebei Province. The result shows that the relative errors are no larger than 1%, which indicts a successful calibration.

Comparative Study of Computing Methods of Soil Temperature on Different Underlying Surfaces

ZHANG Haihong,LIU Shuhua,WEI Zhigang,Lv Shihua,HOU Xuhong,WEN Jun,GAO Xiaoqing

2011, 47(6):  1025-1033. 

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Using soil temperature data observed at Dunhuang, Badanjilin Desert center, Badanjilin Desert edge and Pingliang from July to Aug. 2009, the soil thermal diffusivity and soil water flux density are calculated with thermal conduction algorithm and thermal conduction-convection algorithm. Based on these results and taking the soil layer at the depth of 5 cm as the upper boundary, the soil temperatures at the depth of 10 cm in the 4 areas are modeled using the two algorithms. The results show that both of the two methods could correctly model the soil temperature, and the soil temperature modeled at daytime is more exact. The soil thermal diffusivities of Dunhuang, Badanjilin Desert center, Badanjilin Desert edge and Pingliang are 1.62 × 10^-7, 6.92 × 10^-7, 8.01 × 10^-7and 16.10 × 10^-7m²/s, and the soil water flux densities of Badanjilin Desert center, Badanjilin Desert edge and Pingliang are 4.72, 9.22 and 7.06 m2/s. The standard error of soil temperature modeled by thermal conduction algorithm is less at Dunhuang Gobi, where the soil moisture is low. The standard errors of soil temperature modeled by thermal conduction-convection algorithm are less at Badanjilin Desert center, Badanjilin Desert edge and Pingliang, where the soil moistures are high.

Organic Geochemistry of Triassic Source Rocks in the Southern Qilian Basin

XIE Qifeng,ZHOU Lifa,MA Guofu,TAN Xiuzhong,WAN Yanzhou,LIANG Shiwei,ZHANG Kai,ZHAO Junhui

2011, 47(6):  1034-1040. 

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According to the outdoor profile survey, collection of samples in systematic and the organic geochemical analysis technique including rock pyrolysis, residual organic carbon content, kerogen analysis, organic maceral, vitrinite reflectance, gas chromatography of saturated hydrocarbon and transmitted light microscopy, the authors discussed organic matter abundance, type and maturity of T₃g carbonate and T₂d mudstone outcrop samples in the Southern Qilian Basin, the original sedimentary environment and bio-inputs of organic matter. The results show that T₃g carbonate belong to good source rocks, the organic matter is type Ⅰ~Ⅱ and T₂d mudstone is type Ⅱ~Ⅲ. The organic matter has a high degree of thermal evolution and is at the high and over mature stage. They are deposited in transitional and mainly terrestrial facies. Organic matters are mainly derived from aquatic plant and errestrial life biodegradation.

Environmental Changes and Relationships with Human Activities of Dongtinghu Plain Since 6000 aBP

LI Jun,WANG Shuyun,MO Duowen

2011, 47(6):  1041-1048. 

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A continuous record from the Dongtinghu Lake is presented in this work. The authors provide detailed evidence of particle size, magnetic capacity and pollen analysis of ZK01 core that reveals the changes of lake’s environment and climate since 6000 aBP. The study shows that 6000-4000 aBP, the water depth was deep in the area of ZK01 core and subtropical evergreen broad-leaved forest developed around the lake, implying a hot/humid climate; 4000-1000 aBP, the water depth was still deep with decreasing trend in the late period, and the climate became relatively dry and cool, vegetation changed significantly; 1000-600 aBP, the lake shrank to be a shallow lake and further developed to the alternate shoal and lacustrine bog environment after 600 aBP. The results reveal that hydrological environment and climate change evidently affected the process of regional ancient culture and history. Particularly, the changes of hydrological environment and climate maybe were the main fading reason of prehistoric civilization in Dongtinghu area. Since 1000 aBP, human activities such as embankment and reclamation in the banks of Yangtze River affected obviously the evolution history of flow and sediment process and river-lake environment in Dongtinghu region.

Fractals of Oil and Gas Field Reserve Distribution in Outer Continental Shelf (OCS), Gulf of Mexico Basin

JU Wei,HOU Guiting,XIAO Fangfeng

2011, 47(6):  1049-1055. 

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On the basis of dividing the size of proved oil and gas fields in the outer continental shelf (OCS) of Gulf of Mexico Basin, the authors applied the fractal theory to the study of the relationship between the number of oil and gas fields and their sizes, and discussed the meaning of fractal dimension D. The fractal dimension D is a reflection of the exploratory development level, the larger the fractal dimension D is, the more mature the exploration is. The fractal method is a good way to analyze the size-distribution of oil and gas fields, to decide the exploration degree and to predict the reserve distribution of oil and gas fields.

Geochemistry and Geological Implications of Mafic Dyke Swarms in the Southwestern Area of Zhongtiao Mountains

SHU Wulin,HOU Guiting,WANG Chuancheng,XIAO Fangfeng,LI Le

2011, 47(6):  1055-1062. 

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Based on the petrographic and geochemical characteristics, petrogenesis of diabase dyke swarms in the southwestern area of Zhongtiao mountains can be discussed in three groups. The results show that the basaltic magma was derived from partial melting of an enriched mantle. Group 1 directly came from initial mantle magma and experienced a small amount of fractional crystallization of mafic minerals. Groups 2 and 3 were derived from a mixing of the mantle and the crust magmas, which experienced fractional crystallization of plagiocalse and Ti-Fe oxides. Compared with group 2, group 3 might undergo significantly crustal contamination and hydrothermal alteration. They were formed in the intraplate extensional environment, which might be related to the extension of the Xionger-Zhongtiao aulacogen.

Research on Focal Mechanism Solutions of Wenchuan Earthquake Sequence

CUI Xiaofeng,HU Xingping,YU Chunquan,TAO Kai,WANG Yanhua,NING Jieyuan

2011, 47(6):  1063-1072. 

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Based on the initial P wave polarity of digital wave form data given by Chinese National Seismic Network, regional seismic network, temporary seismic networks as well as some IRIS stations, employing the improved grid point test method, 121 reliable focal mechanism solutions of Wenchuan earthquake sequence (M 4.0) are determined. The results show that the initial rupture of mainshock is purely thrust. The aftershocks of Wenchuan earthquake sequence are mostly thrust or strike-slip, and there is a characteristic of subsection distribution. The P axes shows a dominant distribution in the directions of NWW-SEE and NEE-SWW.

Eco-environmental Variables Estimation from Remotely Sensed Data and Eco-environmental Assessment: Models and System

SUN Quan,ZHANG Xianfeng,JIANG Miao

2011, 47(6):  1073-1080. 

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Considering the insufficiency of conventional observational means in arid eco-environmental monitoring, this paper examines the requirements for eco-environmental monitoring, as well as the characteristics of the land cover types and climate in arid areas. According to the needs for eco-environmental monitoring and assessment tasks in the arid areas, remote sensing inversion technology was incorporated into the estimation of significant eco-environmental parameters and variables, based on which further assessment models were correspondingly built. In the Microsoft .Net environment, the ArcEngine GIS component was applied to develop the software modules for remote sensing image data visualization and spatial analysis functions, and the IDL language was used to implement the algorithms for remote sensing inversion for the estimation of the land surface variables. Finally a computer system for remote sensing based inversion and assessment of eco-environmental variables and quality in the Shihezi area were implemented and integrated. This system was practically utilized for eco-environmental monitoring and assessment in the study area afterwards. The results show that the system can be operated steadily and is quite useful for rapid estimation of regional significant eco-environmental variables such as vegetation index, soil moisture, land surface temperature, fractional vegetation coverage, net primary productivity, and so on. The system can also aid in the eco-environmental assessment tasks and offer technical support and promote the use of geospatial technology for eco-environmental protection and monitoring in the arid areas.

Life Cycle Greenhouse Gas Emission Assessment of Fuel Ethanol Based on EIO-LCA

LI Xiaohuan,JI Junping,MA Xiaoming,WANG Jingtian

2011, 47(6):  1081-1088. 

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A hybrid life cycle assessment model is built based on Chinese Economic Input-Output Life Cycle Assessment (EIO-LCA) Model 2007 and PLCA. The life cycle GHG emissions of cassava ethanol are calculated and its indirect emission is then allocated into 43 sectors. The results indicate that the life cycle GHG emission of cassava ethanol is 96.2 g/MJ, direct emission, indirect emission and carbon absorbed by photosynthesis is 130.2 g/MJ, 36.9 g/MJ and 70.9 g/MJ, respectively. The electric and heat power sector contributes the most emission in the indirect emission of cassava ethanol, accounts for 32.2%. Compared with traditional gasline, GHG emission reduction of cassava ethanol is not obvious. The hybrid method has the capacity to calculate the life cycle GHG emissions of cassava ethanol more comprehensively, and to reflect the distribution of indirect emission in the sectors of production chain, thus it can help improve policy making in emission reduction.

Accounting Provincial Eco-economic System in China Using a Modified Emergy-Based Ecological Footprint Model

GAO Yang,FENG Zhe,WANG Yang,LI Shuangcheng

2011, 47(6):  1089-1096. 

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By using a modified emergy-based ecological footprint model and Theil index, the authors accounted and analyzed the changing process of the per capita consumption ecological footprint and local output ecological carrying capacity in China in 1996, 2000, 2004 and 2008. The results show that the absolute value of the improved model results was significantly higher than the traditional model. Overall per capita ecological footprint, ecological carrying capacity and ecological surplus and deficit were higher in east region than in middle and west regions. Analysis of the Theil index show that during 1996 and 2008 the main differences between the regions were caused by the differences within intra region rather than the inter-region. At the regional level, differences among the three regions remained stable; at provincial level, difference slightly decreased in east and middle regions, while the west region decreased significantly.

A Simulation Research of Nonlinear Lowry Model Based on Genetic Algorithm

ZHOU Binxue,DAI Teqi,LIANG Jinshe,ZHANG Hua

2011, 47(6):  1097-1104. 

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Under the principle of genetic algorithm, by using the genetic algorithm toolbox, after proving the applicability of genetic algorithm on a numerical example of 3 zones, 3-section economy of nonlinear Lowry model, the authors use this model to perform a simulated experiment on 9 zones, 3-section economy under a fan-shaped urban framework. The results show that, at first, if the residential charm of every district is at the same degree, traffic factor will play a very important role in residential structure of urban area; secondly, the district at the best traffic location owns the highest population density. Because of the limitation of land and maximization of economic goal, this type of district is the first choice to the industry which have high added value. This article shows a good explanatory ability of nonlinear Lowry model and lays a good foundation for the practical simulated research of urban.

Risk Assessment on Food Crops Supply-Demand Balance under Climate Change in China

ZHOU Qiaofu,DAI Erfu,WU Shaohong,PAN Tao,CHEN Xiwei

2011, 47(6):  1105-1115. 

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The term “risk” here mainly refers to the possible impacts of future climate change on food crops supply-demand balance. Based on the simulated results of food crops production under scenario B2 of climate change in RCMCA (regional crop model for Chinese agriculture), this study developed the food crops consumption scenario and set the criteria on food crops risks under climate change. It also analyzed the future variation in food crops supply and demand to determine the effect of climate change on food crops security in the short, medium and long terms at the county scale with the support of GIS. The results show that the climate change will hinder the food crops supply in general. With higher living standard, the gap between food crops supply and demand will be enlarged in the future, resulting in the increase of risk. The highest may occur in the medium term, the lowest in the near future, and the medium in the far future. Particularly in the medium term, 66.99% of the counties in China will face risks. Among them, 29.5%, occupying the largest area, will be with high and moderate risks; in the short-term, however, the situation will be easier, i.e. 25.54% counties in moderate (14.82%) and high risks (10.72%). Moreover, counties with high risks are distributed mainly in Huang-Huai-Hai Region, Loess Plateau, Southwest China, and Eastern Margin of Qinghai-Tibet Plateau Region. The areas with lower risks are in Northeast Region, Gansu Province and Xinjiang Uygur Autonomous Region, and Inner Mongolia Autonomous Region and areas along the Great Wall.

Research on the Pretreatment of Black Liquor Produced from Refined Cotton Production by Acidification-Coagulation-Micro-electrolysis

YU Yu,YE Zhengfang,ZHAO Quanlin

2011, 47(6):  1116-1120. 

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Black liquor produced from refined cotton production is highly concentrated refractory organic wastewater containing complicated components. Pretreatment by physical-chemical processes is preferred. The Acidification-Coagulation-Micro-electrolysis (ACM) was adopted to pretreat the black liquor. The effect of pH was investigated. UV-vis analysis and acute toxicity test were used for monitoring the changes of the composition. The results showed that the best pH value was 2 for acidification, 12 for coagulation and 4?5 for micro-electrolysis. COD decreased from 5400 to 1900 mg/L by the ratio of 65%. BOD5 decreased from 2860 to 1080 mg/L by the ratio of 62%. TOC decreased from 2080 to 906 mg/L by the ratio of 56%. Chromaticity decreased from 4500 to 50 by the ratio of 99%. Acute toxicity test showed that the dilution ratio of LIR50 (50% of luminosity inhibition rate) decreased from 250 to 17, meaning that the acute toxicity was reduced by 93%. Parts of refractory organic compounds containing conjugated double bonds and aromatic substances were precipitated or degraded. ACM for black liquor achieved good effect, providing favorable conditions for subsequent biological treatment.

Residents’ Perception on Rural Event and Event Tourism Impact Based on Structural Equation Model: A Case Study in Changshaoying Village in Bejing

DAI Linlin,GAI Shijie

2011, 47(6):  1121-1128. 

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Take Changshaoying (a village highly developed in event and event tourism (E&ET) in Beijing suburbs) as a case study, based on the data collected during March to May in 2010, the authors use confirmatory factor analysis (CFA) combined with structural equation model (SEM) to get 4 key factors of residents’ perceptions from 19 items, defining the perceptions on “humane environment improvement”, “economic life improvement”, “environment deterioration” and “social contradiction” as first-order latent variables, perceptions on “event costs” and “event profits” as second-order latent variables, residents’ participation and support degree as latent variables. A tri-correlate structural equation model is established to measure the logical relations between these three (perceptions, participation and support degree of the residents) and verify 5 relevance assumptions. The result shows a positive correlation between participation and costs/profits perception, a positive correlation between participation and support degree, a positive correlation between profits perception and support degree, but a negative between costs perception and support degree. In detail, participation effects profits perception far more than costs perception, alike profits perception plays a more important role than costs perception in effecting supporting degree of the residents.

Surface Air Temperature Changes of Different Land Cover Types in China during 1979-2007

LI Yan,ZHAO Xinyi

2011, 47(6):  1129-1136. 

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The surface air temperature changes of different land cover types in China were investigated by using observation minus reanalysis (OMR) method. The OMR trends for the 1979?2007 period were estimated from NCEP/NCAR Reanalysis 1 and surface observation temperature monthly data, which showed that China had an overall OMR warming trend of 0.18℃/10a. The OMR trends with respect to different land cover types were analyzed based on AVHRR land cover classification data. The results show that the sensitivity of surface air temperature to different land cover types is different. Most of the land types show positive OMR trends, while forests show negative trends. OMR results with land type under different thresholds are quite similar, which indicates the robustness of this method.

Psychological Effect Analysis for Volunteers of National Day Celebration

MA Huaxiang,QIN Bo,WU Hao,XIE Xiaofei

2011, 47(6):  1137-1142. 

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The authors explored the positive mental effects of the National Day celebration on the participants ? the undergraduate volunteers of Peking University, and discussed in details its possible mechanism. Through distributing questionnaires before and after the celebration, the research found the National Day celebration could significantly increase individuals’ sense of national identity, and also tested the mediation of sense of national identity. Result showed that the National Day celebration could promote participants’ volunteering willingness and life satisfaction; sense of national identity, rather than the affective reaction, was the mediator variable between them. According to the self-presentation theory, National Day celebration would enhance sense of nation identity and self-esteem. The results were also discussed in terms of theoretical and practical implications.

China’s Air Pollution Control Strategy and Reform

WU Dan,ZHANG Shiqiu

2011, 47(6):  1143-1150. 

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There has been severely regional compound pollution in China now. However, the existing institutional arrangement of air quality management has not responded to the emerged pollution situation. The authors analyze two key limitations of existing air pollution control strategy. First, the in-effective feature due to the pollution control target setting based only on emission reduction, and only for key pollutant; second, the costly feature in the long-term due to design of the control strategy based on major but single pollutant as well as the local based pattern. Referencing to the international experience, the authors give suggestions that transforming air pollution control target from emission reduction to damage reduction (or air quality improvement); transforming control strategy from single pollutant control to multi-pollutant control; and developing an ecological compensation mechanism based on regional air quality management.

LED Failure Analysis with Phenomenon of Resonant Tunneling Model

YUAN Chen,YAN Wei

2011, 47(6):  1151-1154. 

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The authors provided a failure analysis method of LEDs based on the fact that LEDs suffered electro- static damage sometimes were familiar with the resonant tunneling diode (RTD) model. After they were destroyed by HBM model over 500-3000 V, part of the failure LEDs showed as a resonant tunneling diode (RTD) in I-V curves, which proved that the electrostatic damage path went through the LED internal quantum wells. By contrasting with more devices, a set of I-V curve analysis method can be established for the location of LED damage. This failure analysis with the advantage of reducing observations by OBIRCH can be enriched through experience.

Effect of Polymer Coating on Electrochemical Performance of Novel LiFeBO₃ Cathode Materials

YANG Chi,WANG Hong,GUO Chuntai,SUN Li’an

2011, 47(6):  1155-1158. 

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The cathode materials of LiFeBO₃ was prepared by means of solid reaction with lithium metaborate and ferric oxide as raw materials. LiFeBO₃ were coated with silicone polymer solution. The samples were characterized by X-ray diffraction and scanning electron microscopy. Electrochemical tests of materials showed that LiFeBO₃ exhibited a higher discharge mass specific capacity. The coated samples demonstrated the improved performance. Sample coated with 5% silicone had a initial capacity 195 mAh/g. There was only 4.3% capacity loss after 50 cycling.