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Synthesis and Biological Activity of New Pyrethroid Acid Oxime-esters Containing Pyrazole Ring

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Chemical Research in Chinese Universities 2003年第3期19卷 297-301页

作者： MA Jun-an HUANG Run-qiu FENG Lei SONG Jian qiu De-wen Institute and State Key Laboratory of Elemento-organic Chemistry Nankai UniversityTianjin 300071P.R.China

A series of compounds containing oxime-ester linkage and pyrazole ring(in place of the ester linkage and the alcohol moiety in pyrethroid ester) was designed and synthesized. The structures of all the compounds prepared were confirmed by 1H NMR and MS spectroscopy as well as elemental analyses. The bioassay data of those compounds against tobacco mosaic virus(TMV), cucumber mosaic virus(CMV), potato virus X(PVX) and potato virus Y(PVY) were presented. Among them compound 6i was found to possess significant plant antiviral activities. But all the compounds showed low insecticidal and acaricidal activities.

关键词： Pyrethroid Oxime-ester Synthesis Pyrazole Plant antiviral activity

Research on fuzzy self-adaptive PI-Smith control in long time-delay system

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The Journal of China Universities of Posts and Telecommunications 2011年第5期18卷 114-117,128页

作者： WEI qiu-yue WANG wen-qing School of Automation Xi＇an University of Posts and Telecommunications Xi＇an 710121 China

The long time-delay often exists in industrial process. In order to overcome the big overshoot and long regulating time of the long time-delay system control, a new fuzzy self-adaptive PI-Smith control method is proposed. This method combines the Smith predictive control with fuzzy self-adaptive proportional-integral （PI） control. The traditional proportional-integral-derivative （PID） controller in Smith predictive control is replaced by fuzzy PI controller which utilizes the principle of fuzzy control to tune parameters of PI controller on-line. The results of simulation for electric furnace show that the method has the advantages of shortening regulating time, no overshoot, no steady-state error, excellent control accuracy, and good adaptive ability to the change of system model.

关键词： self-adaptive fuzzy PI control Smith predictive control long time-delay

Solvent-free mechanochemical mild oxidation method to enhance adsorption properties of chitosan

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Frontiers of Environmental Science & Engineering 2021年第6期15卷 353-366页

作者： Mohammadtaghi Vakili wen qiu Giovanni Cagnetta Jun Huang Gang Yu Green Intelligence Environmental School Yangtze Normal UniversityChongqing 408100China State Key Joint Laboratory of Environment Simulation and Pollution Control(SKJLESPC) Beijing Key Laboratory for Emerging Organic Contaminants Control(BKLEOC)School of EnvironmentTsinghua UniversityBeijing 100084China

Oxidation has been profitably utilized to improve some properties of ***,only solventbased oxidation procedures have been proposed so far,which are hardly feasible at industrial scale in an economic way because of product recovery *** this study,a solvent-free,rapid,and effective oxidation method is *** is based on direct solid-state reaction between chitosan and oxidant powder in a mechanochemical *** prove that by short high energy ball milling(<3 h)it is possible to achieve diverse physicochemical modifications employing different *** from polysaccharidic chain shortening,persulfate provokes high amorphization and induces formation of ketonic groups;percarbonate heightens deacetylation degree,preserving in part crystallinity;calcium peroxide merely deprotonates amino groups and increases amorphization *** tests with the azo-dye reactive red 2 show that adsorption capacity of chitosan co-milled with persulfate(974 mg/g milled product),which is the best performing adsorbent,is twice that of pristine chitosan,while adsorption rate is outstandingly boosted(125 times).

关键词： Chitosan High energy ball milling Mechanochemistry Oxidation

Energy Buildup,Flux Confinement and Helicity Accumulation in the Solar Corona

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Chinese Journal of Astronomy and Astrophysics 2006年第1期6卷 77-86页

作者： You-qiu Hu wen Li School of Earth and Space Sciences University of Science and Technology of China Hefei230026

Starting from a dipole field ment of field lines on the photosphere, and a given distribution of footpoint displacewe find axisymmetric, force-free field solutions in spherical coordinates that have the same distribution of normal field on the photosphere and magnetic topology as the dipole field. A photospheric shear is introduced in the azimuthal direction in a region that strides across the equator and ends at latitude λs. The footpoint displacement has a sine distribution in latitude and a peak amplitude of φm. The magnetic energy E, azimuthal flux Fφ, and magnetic helicity lit in the solar corona are then calculated for each force-free field solution. It is found that for a given shear region range λs, all of the three quantities increase monotonically with increasing φm. In particular, both Fφ and HT have a linear dependence on φm. When φm reaches a certain critical value φmc, the force-free field loses equilibrium, leading to a partial opening of the field and the appearance of a current sheet in the equatorial plane. At this point, E, Fφ and HT reach their maximum values, Ec, Fφc and HTo Ec increases, and Fφc and HTc decrease with decreasing λs. It is found that Ec is always smaller than the open field energy, in agreement with the Aly conjecture. Of the three critical parameters, Ec has the weakest dependence on λs. Therefore, if one is interested in the transition of a magnetic configuration from a stable state to a dynamic one, the magnetic energy is probably the most appropriate marker of the transition.

关键词： Sun: magnetic fields -- Sun: force-free fields methods: numerical

Refined mathematical model for the breaching of concrete-face sand-gravel dams due to overtopping failure

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Journal of Mountain Science 2023年第3期20卷 670-687页

作者： qiu wen LI Yan-long wen Li-feng WANG Jing YIN Qiao-gang State Key Laboratory of Eco-hydraulics in Northwest Arid Region Xi'an University of TechnologyXi'an 710048China

Overtopping is one of the main reasons for the breaching of concrete-face sand-gravel dams(CFSGDs).In this study,a refined mathematical model was established based on the characteristics of the overtopping breaching of *** model characteristics were as follows:(1)Based on the Renormailzation Group(RNG)k-εturbulence theory and volume of fluid(VOF)method,the turbulent characteristics of the dam-break flow were simulated,and the erosion surface of the water and soil was tracked;(2)In consideration of the influence of the change in the sediment content on the dam-break flow,the dam material transport equation,which could reflect the characteristics of particle settlement and entrainment motion,was used to simulate the erosion process of the sand gravels;(3)Based on the bending moment balance method,a failure equation of the concrete face slab under dead weight and water load was *** proposed model was verified through a case study on the failure of the Gouhou *** results showed that the proposed model could well simulate the erosion mode of the special vortex flow of the CFSGD scouring the support body of the concrete face slab inward and reflect the mutual coupling relationship between the dam-break flow,sand gravels,and concrete face *** with the measured values,the relative errors of the peak discharge,final breach average width,dam breaching duration,and maximum failure length of the face slab calculated using the proposed model were all less than 12%,thus verifying the rationality of the *** proposed model was demonstrated to perform better and provide more detailed results than three selected parametric models and three simplified mathematical *** study results can aid in establishing the risk level and devising early warning strategies for CFSGDs.

关键词： Concrete-face sand-gravel dam Overtopping Dam-break flow Concrete face slab failure Refined mathematical model

Development of 1D and 2D coupled model to simulate urban inundation:An application to Beijing Olympic Village

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Chinese Science Bulletin 2009年第9期54卷 1613-1621页

作者： LI WeiFeng CHEN qiu wen MAO JingQiao The State Key Lab of Urban and Region Ecology The Centre for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Urban inundation due to anomalous storms is a serious problem for many cities worldwide. Therefore, it is important to accurately simulate urban hydrological processes and efficiently predict the potential risks of urban floods for the improvement of drainage designs and implementation of emergency ac-tions. However, the complexity of urban landforms and the diversity of hydraulic infrastructure pose particular challenges for the simulation and risk assessment of urban drainage processes. This study developed a methodology to comprehensively simulate inundation processes by dynamically coupling 1D and 2D hydrodynamic models. By allowing the simultaneous solution of the processes of rainfall and runoff, urban drainage, and flooding, this method can be used to estimate the potential inundation risks of any designed drainage system. Furthermore, a Geographical Information System (GIS) based platform was fully integrated with the model engine to effectively illustrate the context of the problem. The developed model was then demonstrated on the Beijing 2008 Olympic Village under the conditions of the 5-year and 50-year design storms. The sewer discharge, channel discharge, and flood propaga-tion (inundation initiation, extent, depths, and duration) were numerically validated and analyzed. The results identified the potential inundation risks. From the study, it is found that the coupled GIS and 1D and 2D hydrodynamic models have the potential to simulate urban inundation processes, and hence efficiently predict flood risks and support cost-effective drainage design and management. It also im-plies promising prospects about the wide availability of high quality digital data, GIS techniques, and well-developed monitoring infrastructure to develop online urban inundation forecasts.

关键词：城市洪水耦合模型奥运村淹没模拟二维一维地理信息系统技术

On the Stability of a Mixed Functional Equation Deriving from Additive, Quadratic and Cubic Mappings

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Acta Mathematica Sinica,English Series 2014年第6期30卷 1033-1049页

作者： Li Guang WANG Kun Peng XU qiu wen LIU School of Mathematical Sciences Qufu Normal University Zaozhuang Economics School

In this paper, we investigate the general solution and the Hyers–Ulam stability of the following mixed functional equation f（2x ＋ y）＋ f（2x- y） = 2f（2x）＋ 2f（x ＋ y）＋ 2f（x- y）- 4f（x）- f（y）- f（-y）... 详细信息

关键词： Additive mapping quadratic mapping cubic mapping Hyers–Ulam stability

The Effects of Different Tillages on Crop Residue Sequestration, Soil Available Nutrients and Some Biochemical Properties in the Chinese Black Soil Region

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Agricultural Sciences in China 2011年第4期10卷 576-584页

作者： LIU Xiao-li CHEN qiu-wen ZENG Zhao-xia State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 P.R.China Key Laboratory of Agro-Ecology Institute of Subtropical Agriculture Chinese Academy of Sciences Changsha 410125 P.R.China College of Resources ＆ Environment Hunan Agricultural University Changsha 410128 P.R.China

Three-year field experiments were conducted to investigate the effects of different tillage operations after harvest on crop residues sequestration and their subsequent effects on soil available nitrogen （N）, phosphorus （P）, some soil biochemical properties, and three enzymatic activities during the following growing seasons in a soybean （Glycine max）-soybean- corn （Zea mays） rotation farming system in Northeast China. Two different managements were implemented after crop harvest every year, which were tillage （T） and no tillage （NT）. Results showed that crop residue masses on soil surface and in the 0-20 cm layer after soybean harvest were about 1 450 and 340 kg ha-1, respectively, in October 2006 and 2007. While, soybean residue mass in the 0-20 cm soil layer was about 340 kg ha-1 in NT and about 1 550 kg ha-1 in T before sowing in May 2007 and 2008. The adverse results were found after corn crop plantation, that corn residue mass was about 270 and 860 kg ha-1 on soil surface and in the 0-20 cm soil layer, respectively, after harvest in October 2008, while residue mass in the 0-20 cm soil layer was only 466 kg ha-1 in T but 863 kg ha-1 in NT before planting in May 2009. So T had effectively sequestered soybean residue into soil but not corn. Results also showed that T after harvest helped to improve soil available N, P, soil microbial biomass carbon （MBC）, and nitrogen （MBN） contents and soil enzymes activities （urease, acid phosphatase, and protease） during the 2007 and 2008 seasons, but the positive effects decreased during the 2009 season. T practice had significant positive effects on available N, P, MBC, and MBN contents, protease and urease activities, however, no obvious effects on acid phosphatase activity. In this study, T practice after soybean harvest was proved to be preferable to improve soil microbial and enzyme activities during the following seasons due to an efficient sequestration of soybean residues. However, NT could be considered preferential

关键词： crop residues tillage soil biochemical properties Northeast China

Multilevel Assessment of Spatiotemporal Variability of Vegetation in Subtropical Mountain-hill Region

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Journal of Mountain Science 2013年第6期10卷 1028-1038页

作者： qiu Bing-wen ZENG Can-ying TANG Zheng-hong Key Laboratory of Spatial Data Mining & Information Sharing of Ministry of Education Spatial Information Research Centre of Fujian Province Fuzhou University Community and Regional Planning Program University of Nebraska-Lincoln

The complex spatiotemporal vegetation variability in the subtropical mountain-hill region was investigated through a multi-level modeling framework. Three levels - parcel, landscape, and river basin levels- were selected to discover the complex spatiotemporal vegetation variability induced by climatic, geomorphic and anthropogenic processes at different levels. The wavelet transform method was adopted to construct the annual maximum Enhanced Vegetation Index and the amplitude of the annual phenological cycle based on the 16-day time series of a5om Moderate Resolution Imaging Spectroradiometer Enhanced Vegetation Index datasets during 2OOl-2OlO. Results revealed that land use strongly influenced the overall vegetation greenness and magnitude of phenological cycles. Topographic variables also contributed considerably to the models, reflecting the positive influence from altitude and slope. Additionally, climate factors played an important role： precipitation had a considerable positive association with the vegetation greenness, whereas the temperature difference had strong positive influence on the magnitude of vegetation phenology. The multilevel approach leads to a better understanding of the complex interaction of the hierarchical ecosystem, human activities and climate change.

关键词： Enhanced Vegetation Index Multilevelmodel Wavelet transform Mountain-hill region Spatiotemporal variability