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Chinese Journal of Polymer Science 2017年第9期35卷 1132-1142页

作者： wen-jin yu shu-man xu li zhang 傅强 College of Polymer Science and Engineering State Key Laboratory of Polymer Materials Engineering Sichuan University Chengdu 610065 China

In this work, completely immiscible polyethylene/polyamidel2 （PE/PA12） blends were prepared by high shear extruder. The morphology and mechanical properties of the blends were investigated as a function of rotation speed. It was found that the high shear processing is an effective method to improve the dispersion of the PAl2 phase in PE matrix when PA 12 contents are 5 wt% and 10 wt%, and the dispersed phase particle size is reduced with the increase of rotation speed from 100 r/min to 500 r/min. However, with further increase of PAl2 content to 20 wt%, high shear processing has no effect on the phase morphology of the blends. Accordingly, a largely increased elongation at break and impact strength are observed for PE/PAl2/95/5 and PE/PA12/90/10 blends obtained at high rotation speeds but no effect on the property of PE/PAI2/80/20. Annealing experiment demonstrated that the obtained phase morphology is not stable thus compatibilizer should be introduced in the future work. This work could provide a guideline for the application of high shear processing in the preparation of polymer blends with huge polarity difference.

关键词： Immiscible polyethylene/polyamidel2 (PE/PA12) blends High shear processing Phase morphology

A Computer Program for Automatic Watering Based on Potential Evapotranspiration by Penman Method and Predicted Leaf Area in Miniature Pot Rose Production

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Agricultural Sciences in China 2010年第3期9卷 370-377页

作者： yu wen-jin Kitamura Ryo Kato Katsuhiko LI Lian-hua Fukui Hirokazu Agricultural College Guangxi University Nanning 530004 P.R.China The United Graduate School of Agricultural Science Gifu University Gifu 5011193 Japan Faculty of Applied Biological Sciences Gifu University Gifu 5011193 Japan Gifu Prefectural Center for Agricultural Sciences Gifu 5011152 Japan

In this study, we developed a computer program for automatic prediction of watering time point by considering the environmental factors such as solar radiation, air temperature and relative humidity based on the multiple linear regression equation of leaf area and Penman Method. The experiments were carried out for a year in two watering experimental plots, one of which was controlled by pF value, and the other by the computer program. After comparing the results of the two plots, the following findings were obtained. In the computer program plot, the observed and predicted values of both leaf area and evapotranspiration indicated significant correlation at the 1% level, which suggested that the computer program had high prediction accuracy. In addition, no significant difference was observed between the two experimental plots with respects to the plant height, plant diameter, leaf area, leaf number, fresh weight, and dry weight, which demonstrated that the plants in the computer program plot had normal growth. On the other hand, although the number of flower buds and flowering shoots showed higher values at the end of certain cultivations in the computer program plot than those in pF value plot, we proposed that it was due to the effect of cumulative daily solar radiation in the greenhouse, rather than the watering. Thus, we have reached the conclusion that the computer program for automatic prediction of watering time point developed by this study has high applicability in miniature pot rose production.

关键词： automatic watering leaf area miniature pot rose Penman Method program

A load-balanced minimum energy routing algorithm for Wireless Ad Hoc Sensor Networks

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第4期7卷 502-506页

作者： CAI wen-yu jin Xin-yu ZHANG yu CHEN Kang-sheng Department of Information Science ＆ Electronic Engineering Zhejiang University Hangzhou 310027 China

Wireless Ad Hoc Sensor Networks (WSNs) have received considerable academia research attention at present. The energy-constraint sensor nodes in WSNs operate on limited batteries, so it is a very important issue to use energy efficiently and reduce power consumption. To maximize the network lifetime, it is essential to prolong each individual node’s lifetime through minimizing the transmission energy consumption, so that many minimum energy routing schemes for traditional mobile ad hoc network have been developed for this reason. This paper presents a novel minimum energy routing algorithm named Load-Balanced Minimum Energy Routing (LBMER) for WSNs considering both sensor nodes’ energy consumption status and the sensor nodes’ hierarchical congestion levels, which uses mixture of energy balance and traffic balance to solve the problem of “hot spots” of WSNs and avoid the situation of “hot spots” sensor nodes using their energy at much higher rate and die much faster than the other nodes. The path router established by LBMER will not be very congested and the traffic will be distributed evenly in the WSNs. Simulation results verified that the LBMER performance is better than that of Min-Hop routing and the existing minimum energy routing scheme MTPR (Total Transmission Power Routing).

关键词： Wireless Ad Hoc Sensor Networks (WSNs) Load-Balanced Minimum Energy Routing (LBMER)

Effects of Extreme Air Temperature and Humidity on the Insecticidal Expression Level of Bt Cotton

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Journal of Integrative Agriculture 2012年第11期11卷 1836-1844页

作者： CHENyuan wen yu-jin CHEN yuan John Tom Cothren ZHANG Xiang WANG Yong-hui WilliamA Payne CHEN De-hua Ecology and Cultivation in Middle and Lower Reaches of Yangtse River Ministry of Agriculture/Agricultural College Yangzhou University Yangzhou 225009 P.R.China Department of Soil and Crop Sciences Texas A&M University College Station TX77843 USA Key Laboratory of Crops Genetics and Physiology Jiangsu Province/Agricultural College Yangzhou University Yangzhou 225009 P.R. China Norman Borlaug Institute for International Agriculture Texas A&M University College Station TX77843 USA

The higher survival rates of Helicoverpa amigera larvae were usually observed after adverse climate which was related to extreme temperature （T） and relative humidity （RH） stresses in transgenic Bacillus thuringiensis （Bt） cotton. The unstable resistance of Bt cotton to bollworms has been correlated with the reduced expression of CrylAc δ-endotoxin. The objective of this study was to investigate the effects of combined temperature and relative humidity stresses on the leaf CrylAc insecticidal protein expression during critical developmental stages. The study was undertaken on two transgenic cotton cultivars that share same parental background, Sikang 1 （a conventional cultivar） and Sikang 3 （a hybrid cultivar）, during the 2007 and 2008 growing seasons at the Yangzhou University Farm, Yangzhou, China. The study was arranged with two factors that consisted of temperature （two levels） and relative humidity （three levels）. The six T/RH treatments were 37℃/95%, 37℃/70%, 37℃/50%, 18℃/95%, 18℃/70%, and 18℃/50%. In 2007, the six treatments were imposed to the plants at peak flowering stage for 24 h; in 2008, the six treatments were applied to the plants at peak square, peak flowering, and peak boll stages for 48 h. The results of the study indicated that the leaf insecticidal protein expression in CrylAc was significantly affected by extreme temperature only at peak flowering stage, and by both extreme temperature and relative humidity during boll filling stage. The greatest reductions were observed when the stresses were applied at peak boll stage. In 2008, after 48 h stress treatment, the leaf Bt endotoxin expression reduced by 25.9-36.7 and 23.6-40.5% at peak boll stage, but only by 14.9-26.5 and 12.8-24.0% at peak flowering stage for Sikang 1 and Sikang 3, respectively. The greatest reduction was found under the low temperature combined with low relative humidity condition for both years. It is believed that the temperature and relative humidity stresses may be attribut

关键词： Bt cotton high temperature low temperature relative humidity CryIAc protein

Generating wind power time series based on its persistence and variation characteristics

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Science China(Technological Sciences) 2014年第12期57卷 2475-2486页

作者： LI jing Hua LI Jia Ming wen jin yu CHENG Shi Jie XIE Hai Lian yuE Cheng Yan China State Key Laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science and TechnologySchool of Electrical and Electronic Engineering School of Electrical Engineering Guangxi University ABB (China) Ltd. Corporate Research Center

Generation of wind power time series is an important foundational task for assisting electric power system planning and mak- ing decision. By analyzing the characteristics of wind power persistence and variation, th!.s paper proposes an improved Mar- kov chain Monte Carlo （MCMC） method, identified as the PV-MC method, for the direct generation of a synthetic series of wind power output. On the basis of the MCMC method, duration time and variation features are concluded in PV-MC method, gaining a more comprehensive reflection of wind power characteristics in the generated wind power time series. First, the wind power state series is generated to meet the state transition matrix based on the definition of the wind power state. Then, the time duration of each state in the series is determined by its respective duration character. Finally, the variation characteristic is used to convert the state series to a wind power time series. A significant amount of simulations are performed based on the PV-MC and MCMC methods and are then compared for 25 wind farms at 6 different locations throughout the world. The sim- ulation results show that the PV-MC method offers an excellent fit for the time domain features （persistence and variation characteristic） while holding other statistic features （mean value, variance, autocorrelation coefficient （ACC） and probability density function （PDF）） close to the MCMC method.

关键词： wind power time series generation persistence characteristic variation characteristic markov chain monte carlomethod

The effects of high temperature level on square Bt protein concen-tration of Bt cotton

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Journal of Integrative Agriculture 2015年第10期14卷 1971-1979页

作者： WANG Jun CHEN yuan YAO Meng-hao LI yuan wen yu-jin CHEN yuan ZHANG Xiang CHEN De-hua Jiangsu Provincial Key Laboratory of Crops Genetics and Physiology Yangzhou University Yangzhou 225009 P.R. China Department of Soil and Crop Sciences Texas A&M University College Station TX77843 USA Syngenta Biotechnology Inc. Carry NC 27519 USA

Higher boll worm survival rates were detected after high temperature presented during square period in Bt cotton. The objective of this study was to investigate the effects of high temperature level on the Bt efficacy of two different types of Bt cotton cultivars at squaring stage. During the 2011 to 2013 cotton growth seasons, high temperature treatments ranged from 34 to 44°C in climate chambers, and field experiments under high temperature weather with various temperature levels were conducted to investigate the effects of the high temperature level on square Bt protein concentration and nitrogen metabolism. The climate chamber experiments showed that the square insecticidal protein contents reduced after 24 h elevated temperature treatments for both cultivars, whereas significant declines of the square insecticidal protein contents were detected at temperature 〉38°C, and only slightly numerical reductions were observed when temperature below 38°C. Similar high temperature responses were also observed at the two field experimental sites in 2013. Correspondingly, high temperature below 38°C seems have little effect on the square amino acid concentrations, soluble protein contents, glutamic-pyruvic transaminase（GPT） and glutamic-oxalacetic transaminase（GOT） activities as well as protease and peptidase activities; however, when the temperature was above 38°C, reduced soluble protein contents, enhanced amino acid concentrations, decreased GPT and GOT activities, bolstered protease and peptidase activities in square were detected. In general, the higher the temperature is（〉38°C）, the larger the changes for the above compound contents and key enzymes activities of the square protein cycle. The findings indicated that the unstable insect resistance of the square was related to high temperature level during square stage.

关键词： Bt cotton square high temperature level stress Bt protein nitrogen metabolism

地震灾害对四川省区域生态系统危害及损失评价

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生态学报 2008年第12期28卷 5785-5794页

作者：于文金南京信息工程大学大气科学学院南京210044

地震是自然灾害中最为严重的一种,其带来的生态破坏灾难巨大,区域生态系统损害估算是目前研究中的难点问题之一。对我国西部地震的生态损失特点进行了研究,系统总结国内外地震灾害的生态系统损失评估成果,提出了西部地震生态损失评估模... 详细信息

地震是自然灾害中最为严重的一种,其带来的生态破坏灾难巨大,区域生态系统损害估算是目前研究中的难点问题之一。对我国西部地震的生态损失特点进行了研究,系统总结国内外地震灾害的生态系统损失评估成果,提出了西部地震生态损失评估模型:Eq=ED+ERC+ERL,利用指数分析法和机会成本法等构建了地震研究的基本计算模型和理论,提出用地震生态损失量和地震生态损失灾害度相结合的办法来研究具体区域生态系统的地震灾害损失。利用模型计算,四川省在本次地震中森林碳汇储备能力每年损失78.1万t,损失价值2.5×108元,森林释放氧气能力降低67.38万t,损失价值2.7×108元。直接生态系统损失(ED)647.58×108元,生态系统恢复费用(ERC)1158.31×108元,全省森林生态系统生态服务价值损失达1055.88×108元,综合生态损失在3527.31×108元,灾度0.38,属于明显灾害破坏。灾害损失和灾害度的快速评估对于指导灾后生态系统重建工作和生态系统工程的防灾都具有重要的积极作用。

关键词：地震生态系统灾害评估汶川

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含风电电力系统的主从博弈经济调度

控制理论与应用 2018年第5期35卷 653-661页

作者：仉梦林艾小猛文劲宇华中科技大学电气与电子工程学院强电磁工程与新技术国家重点实验室

风力发电具有显著的随机性和波动性,对电力系统原有调度模式提出挑战.采用鲁棒优化处理风电不确定性,利用鲁棒优化蕴含的博弈思想,将风电场看作调度中心的一个虚拟博弈者,利用双层规划法建立了二者的主从博弈模型,将调度中心看作领导层... 详细信息

风力发电具有显著的随机性和波动性,对电力系统原有调度模式提出挑战.采用鲁棒优化处理风电不确定性,利用鲁棒优化蕴含的博弈思想,将风电场看作调度中心的一个虚拟博弈者,利用双层规划法建立了二者的主从博弈模型,将调度中心看作领导层,其决策目标为电网运行的成本最低,将风电场看作下属层,其决策目标是能保证系统实时安全运行的最大风电出力区间.由于考虑了火电机组的阀点效应,主从博弈模型呈现出非线性双层规划的数学特点,提出一种改进教与学算法与线性规划相嵌套的求解方法.最后,采用改进的10机39节点系统对模型以及求解方法的有效性进行了验证.

关键词：电力系统经济调度鲁棒优化主从博弈风电安全区间教与学算法

Electromagnetic backscattering from one-dimensional drifting fractal sea surface Ⅱ：Electromagnetic backscattering model

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Chinese Physics B 2016年第6期25卷 214-219页

作者：谢涛 William Perrie 赵尚卓方贺于文金何宜军 School of Marine Sciences Nanjing University of Information Science and Technology Nanjing 210044 China Jiangsu Engineering Technology Research Center of Marine Environment Detection Nanjing 210044 China Bedford Institute of Oceanography B2 Y 4A2 Dartmouth NS Canada

Sea surface current has a significant influence on electromagnetic（EM） backscattering signals and may constitute a dominant synthetic aperture radar（SAR） imaging mechanism. An effective EM backscattering model for a one-dimensional drifting fractal sea surface is presented in this paper. This model is used to simulate EM backscattering signals from the drifting sea surface. Numerical results show that ocean currents have a significant influence on EM backscattering signals from the sea surface. The normalized radar cross section（NRCS） discrepancies between the model for a coupled wavecurrent fractal sea surface and the model for an uncoupled fractal sea surface increase with the increase of incidence angle,as well as with increasing ocean currents. Ocean currents that are parallel to the direction of the wave can weaken the EM backscattering signal intensity, while the EM backscattering signal is intensified by ocean currents propagating oppositely to the wave direction. The model presented in this paper can be used to study the SAR imaging mechanism for a drifting sea surface.

关键词： fractal ocean current electromagnetic scattering normalized radar cross section(NRCS)

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变阻抗桩纵向振动的半解析解

重庆交通大学学报（自然科学版） 2009年第3期28卷 518-524页

作者：虞文锦浙江交通职业技术学院路桥系浙江杭州311112

考虑桩周土体的三维波动效应,分析成层黏性材料阻尼土中桩顶受任意轴向激振力作用时变阻抗桩的纵向振动特性,求得桩顶频域响应解析解、复刚度和速度导纳,分析了底部土层模量变化和桩身阻抗变化对桩纵向振动特性的影响。

关键词：三维波动效应黏性材料频域响应复刚度速度导纳