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High-Confidence Computing 2024年第3期4卷 64-74页

作者： Chao wang Xueqiao Xu ke xiao Yunhua He Guangcan Yang School of Information Science and Technology North China University of TechnologyBeijing 100144North China University of TechnologyBeijing 100144

Recently,vehicles have experienced a rise in networking and informatization,leading to increased security *** the most widely used automotive bus network,the Controller Area Network(CAN)bus is vulnerable to attacks,as security was not considered in its original *** paper proposes SIDuBzip2,a traffic anomaly detection method for the CAN bus based on the bzip2 compression *** proposed method utilizes the pseudo-periodic characteristics of CAN bus traffic,constructing time series of CAN IDs and calculating the similarity between adjacent time series to identify abnormal *** method consists of three parts:the conversion of CAN ID values to characters,the calculation of similarity based on bzip2 compression,and the optimal solution of model *** experimental results demonstrate that the proposed SIDuBzip2 method effectively detects various attacks,including Denial of Service,replay,basic injection,mixed injection,and suppression *** addition,existing CAN bus traffic anomaly detection methods are compared with the proposed method in terms of performance and delay,demonstrating the feasibility of the proposed method.

关键词： Automotive safety CAN bus Anomaly detection

多硫化物修饰nZVI@BC对污染土壤中铬的稳定化:铬的生物可用性和稳定机制

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Journal of Central South University 2024年第4期31卷 1217-1232页

作者：陈劲松王鑫晏鑫尧王晓科马慧蒲生彦 State key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China State Environmental Protection key Laboratory of Synergetic Control and Joint Remediation for Soil&Water Pollution Chengdu University of TechnologyChengdu 610059China State key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China

土壤中铬(Cr)污染是最严重的环境问题之一,对人类健康构成了重大威胁。本研究探讨了多硫化物修饰的nZVI@BC(PS-nZVI@BC)对铬污染土壤的稳定化机制以及铬的生物可用性。经过30天的处理后,添加PS-nZVI@BC能够降低土壤中92.0%的可浸出Cr(VI... 详细信息

土壤中铬(Cr)污染是最严重的环境问题之一,对人类健康构成了重大威胁。本研究探讨了多硫化物修饰的nZVI@BC(PS-nZVI@BC)对铬污染土壤的稳定化机制以及铬的生物可用性。经过30天的处理后,添加PS-nZVI@BC能够降低土壤中92.0%的可浸出Cr(VI)。根据序贯萃取分析,添加PS-nZVI@BC后,土壤中的可交换铬从20.8%急剧下降至4.0%,大部分转化为铁锰氧化物和有机物结合态。稳定机制包括静电吸附、氧化还原反应、表面络合和沉淀。此外,PS-nZVI@BC能有效改善铬污染土壤的肥力,降低土壤中的铬对玉米幼苗的毒性。这些结果表明采用PS-nZVI@BC对受铬污染的土壤进行修复具有巨大的潜力。

关键词：铬污染土壤生物炭多硫化物修饰nZVI 土壤修复土壤肥力

长三角地区能源、经济与环境系统协调度发展评价

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生产力研究 2024年第8期 1-5页

作者：马勇刘盈王晓柯上海电力大学经济与管理学院上海201306

长三角是我国最重要的经济区之一,文章把长三角看作一个整体,通过构建能源-经济-环境系统评价指标体系,运用层次分析法对长三角地区的能源-经济-环境系统协调度发展进行了分析,结果发现长三角地区能源-经济-环境系统协调度整体趋势呈“... 详细信息

长三角是我国最重要的经济区之一,文章把长三角看作一个整体,通过构建能源-经济-环境系统评价指标体系,运用层次分析法对长三角地区的能源-经济-环境系统协调度发展进行了分析,结果发现长三角地区能源-经济-环境系统协调度整体趋势呈“N”型,协调度较低,但仍有很大发展空间,总体呈现向上增长的趋势,可以通过区域协调,加快产业结构升级、加强能源利用效率、加大环境污染治理力度等措施进行改善。

关键词：能源-经济-环境系统协调度层次分析法长三角地区

Application of Holdridge life-zone model based on the terrain factor in Xinjiang Automous Region

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Journal of Environmental Sciences 2005年第6期17卷 1042-1046页

作者： NI Yong-ming OUYANG Zhi-yun wang xiao-ke Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

This study improved the application of the Holdridge life-zone model to simulate the distribution of desert vegetation in China which gives statistics to support eco-recovery and ecosystem reconstruction in desert area. This study classified the desert vegetation into four types：（1） LAD： little arbor desert; （2） SD： shrub desert：（3） HLHSD： half-shrub, little half-shrub desert; （4） LHSCD： little halfshrub cushion desert. Based on the classification of Xinjiang desert vegetation, the classical Holdridge life-zone model was used to simulate Xinjiang desert vegetation＇s distribution and compare the Kappa coefficient result of the model with table of accuracy represented by Kappa values. The Kappa value of the model was only 0.19, it means the simulation result was poor. To improve the life-zone model application to Xinjiang desert vegetation type, a set of plot standards for terrain factors was developed by using the plot standard as the reclassification criterion to climate sub-regime. Then the desert vegetation in Xinjiang was simulated. The average Kappa value of the second simulation to the respective climate regime was 0.45. The Kappa value of final modeling result was 0.64, which is the better value. The modification of the model made it in more application region. In the end, the model＇ s ecological relevance to the Xinjiang desert vegetation types was studied.

关键词： Xinjiang desert vegetation types Holdridge life-zone terrain climate regime

Soil Organic Carbon and Its Fractions Across Vegetation Types:Effects of Soil Mineral Surface Area and Microaggregates

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Pedosphere 2009年第2期19卷 258-264页

作者： WU Qing-Biao wang xiao-ke OUYANG Zhi-Yun Forestry College of Guangxi University Nanning 530004 China Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Soil organic carbon(SOC)can act as a sink or source of atmospheric carbon dioxide;therefore,it is important to understand the amount and composition of SOC in terrestrial ecosystems,the spatial variation in SOC,and the underlying mechanisms that stabilize *** this study,density fractionation and acid hydrolysis were used to assess the spatial variation in SOC,the heavy fraction of organic carbon(HFOC),and the resistant organic carbon(ROC)in soils of the southern Hulun Buir region,northeastern China,and to identify the major factors that contribute to this *** results showed that as the contents of clay and silt particles(0–50μm)increased,both methylene blue(MB)adsorption by soil minerals and microaggregate contents increased in the 0–20 and 20–40 cm soil layers(P<0.05).Although varying with vegetation types,SOC,HFOC,and ROC contents increased significantly with the content of clay and silt particles, MB adsorption by soil minerals,and microaggregate content(P<0.05),suggesting that soil texture,the MB adsorption by soil minerals,and microaggregate abundance might be important factors influencing the spatial heterogeneity of carbon contents in soils of the southern Hulun Buir region.

关键词： carbon fractions microaggregates soil mineral surface area soil organic carbon vegetation

Spatial pattern of impervious surfaces and their impacts on land surface temperature in Beijing,China

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Journal of Environmental Sciences 2007年第2期19卷 250-256页

作者： xiao Rong-bo OUYANG Zhi-yun ZHENG Hua LI Wei-feng SCHIENke Erich W wang xiao-ke State key Lab of Urban and Regional Ecology Environmental Sciences Chinese Academy of Sciences Belting 100085 China Department of Science and Technology Studies Rensselaer Polytechnic Institute Troy NY 12180 USA

Land surface temperature （LST）, which is heavily influenced by urban surface structures, is a significant parameter in urban environmental analysis. This study examined the effect impervious surfaces （IS） spatial patterns have on LST in Beijing, China. A classification and regression tree model （CART） was adopted to estimate IS as a continuous variable using Landsat images from two seasons combined with QuickBird. LST was retrieved from the Landsat Thematic Mapper （TM） image to examine the relationships between IS and LST. The results revealed that CART was capable of consistently predicting LST with acceptable accuracy （correlation coefficient of 0.94 and the average error of 8.59%）. Spatial patterns of IS exhibited changing gradients across the various urban-rural transects, with LST values showing a concentric shape that increased as you moved from the outskirts towards the downtown areas. Transect analysis also indicated that the changes in both IS and LST patterns were similar at various resolution levels, which suggests a distinct linear relationship between them. Results of correlation analysis further showed that IS tended to be positively correlated with LST, and that the correlation coefficients increased from 0.807 to 0.925 with increases in IS pixel size. The findings identified in this study provide a theoretical basis for improving urban planning efforts to lessen urban temperatures and thus dampen urban heat island effects.

关键词： urban heat islands urban land cover normalized difference vegetation index (NDVI) climate mitigation regression tree

A new sesquilignan from Selaginella sinensis (Desv.) Spring

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Chinese Chemical Letters 2007年第10期18卷 1224-1226页

作者： Yan Zhi wang Hui Chen xiao ke Zheng Wei Sheng Feng Henan College of Traditional Chinese Medicine Zhengzhou 450008 China

A new sesquilignan, namely sinensiol A, was isolated from the plant of Selaginella sinensis （Desv.） Spring. Its structure was identified on the basis of various spectroscopic data analysis.

关键词： Selaginella sinensis, Sinonsiol A Sesquilignan

The effects of nitrogen fertilizer application on methane and nitrous oxide emission/uptake in Chinese croplands

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Journal of Integrative Agriculture 2016年第2期15卷 440-450页

作者： SUN Bin-feng ZHAO Hong LU Yi-zhong Lü Fei wang xiao-ke State key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 P.R.China University of Chinese Academy of Sciences Beijing 100049 P.R. China College of Resources and Environment China Agricultural University Beijing 100193 P.R. China

The application of nitrogen（N） fertilizer to increase crop yields has a significant influence on soil methane（CH_4） and nitrous oxide（N_2O） emission/uptake.A meta-analysis was carried out on the effect of N application on（i） CH_4 emissions in rice paddies,（ii） CH_4 uptake in upland fields and（iii） N_2O *** responses of CH_4 emissions to N application in rice paddies were highly variable and overall no effects were ***_4 emissions were stimulated at low N application rates（〈100 kg N ha^（-1）） but inhibited at high N rates（〉200 kg N ha^（-1）） as compared to no N fertilizer（control）.The response of CH_4 uptake to N application in upland fields was 15%lower than control,with a mean CH_4 uptake factor of-0.001 kg CH_4-C kg^（-1） *** mean N_2O emission factors were 1.00 and 0.94%for maize（Zea mays） and wheat（Triticum aestivum）,respectively,but significantly lower for the rice（Oryza sativa）（0.51%）.Compared with controls,N addition overall increased global warming potential of CH_4 and N_2O emissions by 78%.Our result revealed that response of CH_4 emission to N input might depend on the CH_4concentration in rice *** critical factors that affected CH_4 uptake and N_2O emission were N fertilizer application rate and the controls of CH_4 uptake and N_2O *** influences of application times,cropping systems and measurement frequency should all be considered when assessing CH_4 and N_2O emissions/uptake induced by N fertilizer.

关键词： nitrogen fertilizer methane nitrous oxide global warming potential emission factor

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留树贮藏对椪柑果实品质和呼吸强度的影响

西南农业学报 2024年第3期37卷 568-576页

作者：李文云罗怿王小柯林乾李金强韩秀梅贵州省果树科学研究所贵阳550006

【目的】探明椪柑留树贮藏果实的品质变化特征,为延长椪柑鲜果供应期提供理论依据。【方法】以留树贮藏椪柑果实为研究对象,以室温贮藏果实为对照,利用液相色谱技术、气相色谱和色度计等果实品质检测方法,研究留树贮藏方式对椪柑果实可... 详细信息

【目的】探明椪柑留树贮藏果实的品质变化特征,为延长椪柑鲜果供应期提供理论依据。【方法】以留树贮藏椪柑果实为研究对象,以室温贮藏果实为对照,利用液相色谱技术、气相色谱和色度计等果实品质检测方法,研究留树贮藏方式对椪柑果实可溶性固形物、果皮色泽、总糖、有机酸和异味等品质和呼吸强度的影响。【结果】椪柑果实留树贮藏40~80 d可溶性固形物含量高于对照,其中60和70 d时分别显著高于对照14.06%和17.28%;总糖在20、40、50和70 d分别比对照低23.31%、6.24%、17.65%和18.82%;留树贮藏10~80 d时柠檬酸含量分别是对照的1.26~1.92倍;红色饱和度a^(*)值降低(30~80 d)2.13~5.03,果皮颜色偏黄,呈橘黄色;除贮藏40 d外,留树贮藏呼吸强度均较对照高1.16%~127.54%;贮藏80 d时异味的代表性物质乙醇含量达峰值(293.28μg/g),室温贮藏是留树贮藏的3.29倍。【结论】生产中建议留树贮藏最佳时间在1月中下旬至2月初春节前后,留树贮藏椪柑果实能够保持色泽橘红,固酸比适宜,风味浓郁,效益好。

关键词：椪柑果实品质留树贮藏室温贮藏

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商洛引种薄壳山核桃试验研究

陕西林业科技 2024年第4期52卷 29-33页

作者：吴宽敏王敏珍王晓珂陈新乐商洛市林业科学研究所陕西商洛726000

为了解新引进的薄壳山核桃在商洛市的生长表现,本研究对2021年从江苏省常州市引种的薄壳山核桃物候期、年生长量、坚果品质等进行了调查分析。结果表明不论是生长量还是结果习性,肖肖尼6号和波尼2号显著优于其他品种(P<0.01),可初步作... 详细信息

为了解新引进的薄壳山核桃在商洛市的生长表现,本研究对2021年从江苏省常州市引种的薄壳山核桃物候期、年生长量、坚果品质等进行了调查分析。结果表明不论是生长量还是结果习性,肖肖尼6号和波尼2号显著优于其他品种(P<0.01),可初步作为优良品种在商洛及同类立地条件进行推广种植。

关键词：商洛薄壳山核桃引种试验