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Impact of ozonation on disinfection byproducts formation from phenylalanine during chlorination

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Journal of Environmental sciences 2024年第10期144卷 199-211页

作者： Sinong Huang Hongwei Liu kunming Wei Liang Zhang Xiaoyan Ma Qingsong Li Xueyan Li Andrea M.Dietrich College of Civil Engineering Zhejiang Key Laboratory of Civil Engineering Structures&Disaster Prevention and Mitigation TechnologyZhejiang University of TechnologyHangzhou 310023China Water Resources and Environmental Institute Xiamen University of TechnologyXiamen 361005China school of Environmental science and Engineering Suzhou University of Science and TechnologySuzhou 215009China Civil and Environmental Engineering Virginia Polytechnic Institute and State UniversityBlackburgVA 24061USA

As a strong oxidizing agent,ozone is used in some water treatment facilities for disinfection,taste and odor control,and removal of organic ***(Phe)was used as the target amino acid to comprehensively investigate variability of disinfection byproducts(DBPs)formation during chlorine disinfection and residual chlorine conditions subsequent to *** results showed that subsequent to ozonation,the typical regulated and unregulated DBPs formation potential(DBPsFP),including trichloromethane(TCM),dichloroacetonitrile(DCAN),chloral hydrate(CH),dichloroacetic acid(DCAA),trichloroacetic acid(TCAA),and trichloroacetamide(TCAcAm)increased substantially,by 2.4,3.3,5.6,1.2,2.5,and 6.0 times,respectively,compared with only *** also significantly increased the DBPs yield under a 2 day simulated residual chlorine condition that mimicked the water distribution *** formations followed pseudo first order *** formation rates of DBPs in the first 6 hr were higher for TCM(0.214 hr^(−1)),DCAN(0.244 hr^(−1)),CH(0.105 hr^(−1)),TCAcAm(0.234 hr^(−1)),DCAA(0.375 hr^(−1))and TCAA(0.190 hr^(−1))than *** peak DBPsFP of TCM,DCAN,CH,TCAcAm,DCAA,and TCAA were obtained when that ozonation time was set at 5–15 *** times>30 min increased the mineralization of Phe and decreased the formation of DBPs upon *** bromine ion(Br^(−1))concentration increased production of bromine-DBPs and decreased chlorine-DBPs formation by 59.3%–92.2%.Higher ozone dosages and slight alkaline favored to reduce DBP formation and *** ozonation conditions should be optimized for all application purposes including DBPs reduction.

关键词： Ozone Amino acids Chlorination Disinfection by-products

Cultural Relevance for Rural Community Development in china: A Case Study in Bai, Jingpo and Huyaodai Communities of yunnan Province

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Chinese Journal of Population,Resources and Environment 2007年第2期5卷 78-83页

作者： Cai Kui1, Du Juan2, Dai Cong3, Hu Huabin4 1. Center for Rural Development Studies, yunnan university, kunming yunnan 650091, china 2. Institute of Ethnology, yunnan Academy of Social science, kunming yunnan 650034, china 3. Institute of Economics, yunnan Academy of Social science, kunming yunnan 650034, china 4. Xishuangbanna Tropical Botany Garden, Chinese Academy of sciences, kunming Yunan 650223, china Center for Rural Development Studies Yunnan University Kunming Yunnan 650091 China Institute of Ethnology Yunnan Academy of Social Science Kunming Yunnan 650034 China Institute of Economics Yunnan Academy of Social Science Kunming Yunnan 650034 China Xishuangbanna Tropical Botany Garden Chinese Academy of Sciences Kunming Yunnan 650223 China

A three-year study over the Bai, Jingpo and Huayaodai communities in yunnan Province reveals that the community development is significantly influenced in various ways by such cultural factors as the concepts of development; concepts and traditions of inter-community relationships, consumption, mar- riage and gender; patterns of decision-making and production, resource and income allocation; as well as the role of information dissemination systems, religion and ritual. Based on the analysis over the interactive relevance between each factor and community development, some strategies and methods for dealing with such a cultural relevance in development projects are recommended.

关键词： ethnic minority cultural relevance community development

Dielectric polymer grafted electrodes enhanced aqueous supercapacitors

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Nano Research 2024年第3期17卷 1525-1534页

作者： Shian Dong kunming Shi Jie Chen Yingke Zhu Hongfei Li Weihang Gao Zhenli Xu Qinglei Liu Xingyi Huang Shanghai Key Laboratory of Electrical Insulation and Thermal Aging Department of Polymer Science and EngineeringState Key Laboratory of Metal Matrix CompositesShanghai Jiao Tong UniversityShanghai 200240China school of Mathematical sciences Institute of Natural Sciences and MOE−LSCShanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong UniversityShanghai 200240China

Supercapacitors(SCs)have become increasingly important in electrical energy storage and delivery owing to their high power densities and long *** SCs are promising for large-scale engineering applications because of their low cost and ***,the low operating voltage and low energy density of aqueous SCs severely limit their practical *** this study,a nanoscale dielectric layer is grafted onto a graphene electrode to achieve both a high operating voltage and enhanced *** with an SC without dielectric grafting,a dielectric-enhanced SC(DESC)shows a higher capacitance by 2200%.The mechanism of the capacitance enhancement can be attributed to three factors:the dielectric polarization,the ions desolvation by the dielectric,and the enhanced quantum capacitance from charge transfer and ion adsorption in the polymer *** addition,a 2.5 V pouch DESC with a 1 M KCl electrolyte is confirmed to cycle up to 50,000 times with a capacitance retention of 87.5%.The DESC presents the optimal electrochemical properties after it is grafted with a 5 nm dielectric *** study provides new insights into the design of high-voltage and high-energy-density aqueous SCs.

关键词： supercapacitors dielectric polymer high voltage capacitance enhancement

Asymmetric interaction will facilitate the evolution of cooperation

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science china(Life sciences) 2010年第8期53卷 1041-1046页

作者： WANG RuiWu1, HE JunZhou1,2, WANG YaQiang1,2, SHI Lei1,3 & LI YaoTang1,2 1 State Key Laboratory of Genetic Resources and Evolution, kunming Institute of Zoology, Chinese Academy of science, kunming 650223, china 2 school of Mathematics and Statistics, yunnan university, kunming 650091, china 3 Statistics and Mathematics College, yunnan university of Finance and Economics, kunming 650221, china 1. State Key Laboratory of Genetic Resources and Evolution Kunming Institute of Zoology Chinese Academy of Science Kunming 650223 China2. School of Mathematics and Statistics Yunnan University Kunming 650091 China3. Statistics and Mathematics College Yunnan University of Finance and Economics Kunming 650221 China

Explaining the evolution of cooperation remains one of the greatest problems for both biology and social science. The classical theories of cooperation suggest that cooperation equilibrium or evolutionary stable strategy between partners can be maintained through genetic similarity or reciprocity relatedness. These classical theories are based on an assumption that partners interact symmetrically with equal payoffs in a game of cooperation interaction. However, the payoff between partners is usually not equal and therefore they often interact asymmetrically in real cooperative systems. With the Hawk–Dove model, we find that the probability of cooperation between cooperative partners will depend closely on the payoff ratio. The higher the payoff ratio between recipients and cooperative actors, the greater will be the probability of cooperation interaction between involved partners. The greatest probability of conflict between cooperative partners will occur when the payoff between partners is equal. The results show that this asymmetric relationship is one of the key dynamics of the evolution of cooperation, and that pure cooperation strategy (i.e., Nash equilibrium) does not exist in asymmetrical cooperation systems, which well explains the direct conflict observed in almost all of the well documented cooperation systems. The model developed here shows that the cost-to-benefit ratio of cooperation is also negatively correlated with the probability of cooperation interaction. A smaller cost-to-benefit ratio of cooperation might be created by the limited dispersal ability or exit cost of the partners involved, and it will make the punishment of the non-cooperative individuals by the recipient more credible, and therefore make it more possible to maintain stable cooperation interaction.

关键词： Hawk–Dove game evolutionarily stable strategy asymmetric cooperation mixed strategy Nash equilibrium

Torque model of hydro turbine with inner energy loss characteristics

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science china(Technological sciences) 2010年第10期53卷 2826-2832页

作者： ZENG Yun1,2, GUO YaKun2, ZHANG LiXiang1, XU TianMao3 & DONG HongKui4 1 Construction Engineering College, kunming university of science and Technology, kunming 650051, china 2 school of Engineering, university of Aberdeen, Aberdeen AB24 3UE, UK 3 Computing Center, kunming university of science and Technology, kunming 650051, china 4 Hydraulic Energy Department, yunnan Electric Power Test and Research Institute, kunming 650217, china 1. Construction Engineering College Kunming University of Science and Technology Kunming 650051 China2. School of Engineering University of Aberdeen Aberdeen AB24 3UE UK3. Computing Center Kunming University of Science and Technology Kunming 650051 China4. Hydraulic Energy Department Yunnan Electric Power Test and Research Institute Kunming 650217 China

This paper presents the result and analysis of the composition of energy loss occurring in the hydro turbine. Two new types of energy losses,namely the hydraulic loss in the flow channel and the impact loss,are defined. All losses within the hydro turbine are divided into four types and the loss coefficients are defined accordingly. Expressions or characteristic descriptions of these losses as well as the calibration method of the loss coefficients are presented. Furthermore,the torque model of the hydro turbine where the inner energy loss takes place is established. The developed model has been used to calculate the power loss due to the mechanical friction generated by the units’ rotation to solve the difficulty of measurements of the mechanical friction loss in the hydro turbine. The definition of the impact loss explains the phenomenon that the loss of no-load is greater than that of the rated operation. A set of conversion coefficients are defined using the characteristic parameters at the rated operation,which are used to transform the parameters in the torque model into those that are easily measured. Therefore,the expression of the hydro turbine power is converted into a function that has the main servomotor displacement as its single variable. This makes the proposed model be convenient to use. Finally,the proposed model and methods are calibrated and verified using the measured data of a hydropower plant. Good agreement between the modeled results and the measurements indicates that the proposed model can represent the inner energy loss characteristics of the hydro turbine.

关键词： hydraulic loss in flow channel impact loss loss coefficients conversion coefficients

Optical pulse compression using a nonlinear optical loop mirror constructed from dispersion decreasing fiber

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science china(Technological sciences) 2004年第1期47卷 33-50页

作者： CAO Wenhua & LIU Songhaoschool of information, Wuyi university, Jiangmen 529020, china school for information and Optoelectronic science and Engineering, South china Normal university, Guangzhou 510631, china 1. school of information Wuyi University 529020 Jiangmen China 2. school for information and Optoelectronic science and Engineering South China Normal University 510631 Guangzhou China

A novel scheme to compress optical pulses is proposed and demonstrated numerically, which is based on a nonlinear optical loop mirror constructed from dispersion decreasing fiber (DDF). We show that, in contrast to the conventional soliton-effect pulse compression in which compressed pulses are always accompanied by pedestals and frequency chirps owning to nonlinear effects, the proposed scheme can completely suppress pulse pedestals and frequency chirps. Unlike the adiabatic compression technique in which DDF length must increase exponentially with input pulsewidth, the proposed scheme does not require adiabatic condition and therefore can be used to compress long pulses by using reasonable fiber lengths. For input pulses with peak powers higher than a threshold value, the compressed pulses can propagate like fundamental solitons. Furthermore, the scheme is fairly insensitive to small variations in the loop length and is more robust to higher-order nonlinear effects and initial frequency chirps than the adiabatic compression technique.

关键词： dispersion decreasing fiber (DDF), optical pulse compression, optical solitons.

Application of Diagonal Recurrent Neural Network toDC Motor Speed Control Systems

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International Journal of Minerals,Metallurgy and Materials 2000年第1期14卷 68-71页

作者： Jing Wang Hui Chen information Engineering school, university of science and Technology Beijing, Beijing 100083, china information Engineering school University of Science and Technology Beijing Beijine 100083 China

A new kind of dynamic neural network--diagonal recurrent neural network (DRNN) and its learning method and architecture are presented. A direct adaptive control scheme is also developed that is applied to a DC (Direct Current) speed control system with the ability to auto-tune PI (Proportion Integral) parameters based on combining DRNN with PI controller. The simulation results of DRNN show better control performances and potential practical use in comparison with PI controller.

关键词： diagonal recurrent neural network PI controller DC Motor speed control system

Multimedia Data Coding and its Development

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International Journal of Minerals,Metallurgy and Materials 2000年第3期14卷 229-232页

作者： Xingye Yu, Yang Yang (information Engineering school, university of science and Technology Beijing, Beijing 100083, china) information Engineering school University of Science and Technology Beijing Beijing 100083 China

The requirements of data coding in multimedia applications are presented, the current technique of coding and relative standards is introduced, then the work that have been doing is presented, i.e. the wavelet-based coding method and the VE (Visual Entropy)-based coding method. The experiment results prove that these methods have gained a better perceptual quality of a reconstructed image and a lower bit rate. Their performance evaluations are better than JPEG (Joint Photographic Experts Group) coding. Finally, the future topics of study are put forward.

关键词： multimedia data coding MPEG (Moving Picture Experts Group) VE (Visual Entropy)

A WT-STFT combining Algorithm

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International Journal of Minerals,Metallurgy and Materials 2000年第4期14卷 315-317页

作者： Xisheng Li, Shaochun Wang (information Engineering school, university of science and Technology Beijing, Beijing 100083, china) information Engineering school University of Science and Technology Beijing Beijing 100083 China

A fast wavelet packet (WP) algorithm is presented, in which the wavelet transform (WT) and the short-time Fourier transform (STFT) are combined. As WT produces multiresolution of frequency and time, and STFT has a fas... 详细信息

关键词： signal processing, wavelet transform short-time Fourier transform Informatid