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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

Effect of ferric and bromide ions on the formation and speciation of disinfection byproducts during chlorination

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Journal of Environmental Sciences 2011年第5期23卷 765-772页

作者： Shaogang Liu Zhiliang zhu Yanling qiu jianfu Zhao State Key Laboratory of Pollution Control and Resource Reuse Tongji University Shanghai 200092 China. E-mail:zzl@*** Department of Chemical and Ecological Engineering Guangxi University for Nationalities Nanning 536000 China

The effects of ferric ion, pH, and bromide on the formation and distribution of disinfection byproducts （DBPs） during chlorination were studied. Two raw water samples from Huangpu River and Yangtze River, two typical drinking water sources of Shanghai, were used for the investigation. Compared with the samples from Huangpu River, the raw water samples from Yangtze River had lower content of total organic carbon （TOC） and ferric ions, but higher bromide concentrations. Under controlled chlorination conditions, four trihalomethanes （THMs）, nine haloacetic acids （HAAs）, total organic halogen （TOX） and its halogen species fractions, including total organic chlorine （TOC1） and total organic bromide （TOBr）, were determined. The results showed that co-existent ferric and bromide ions significantly promoted the formation of total THMs and HAAs for both raw water samples. Higher concentration of bromide ions significantly changed the speciation of the formed THMs and HAAs. There was an obvious shift to brominated species, which might result in a more adverse influence on the safety of drinking water. The results also indicated that high levels of bromide ions in raw water samples produced higher percentages of unknown TOBr.

关键词： disinfection byproducts total organic halogen chlorination ferric ion bromide ion

Scale properties of turbulent transport and coherent structure in stably stratified flows

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Applied Mathematics and Mechanics(English Edition) 2016年第4期37卷 443-458页

作者： Long zhu Xiang qiu jianping LUO Yulu LIU School of Mechanical Engineering Shanghai Institute of Technology School of Science Shanghai Institute of Technology Shanghai Institute of Applied Mathematics and Mechanics Shanghai University

The empirical mode decomposition （EMD） is used to study the scale properties of turbulent transport and coherent structures based on velocity and temperature time series in stably stratified turbulence. The analysis is focused on the scale properties of intermittency and coherent structures in different modes and the contributions of energy-contained coherent structures to turbulent scalar counter-gradient transport （CGT）. It is inferred that the velocity intermittency is scattered to more modes with the development of the stratified flow, and the intermittency is enhanced by the vertical stratification, especially in small scales. The anisotropy of the field is presented due to different time scales of coherent structures of streamwise and vertical velocities. There is global counter-gradient heat transport close to the turbulence-generated grid, and there is local counter-gradient heat transport at certain modes in different positions. Coherent structures play a principal role in the turbulent vertical transport of temperature.

关键词： stratified turbulence coherent structure counter-gradient transport (CGT),empirical mode decomposition (EMD)

Task scheduling for multi-electro-magnetic detection satellite with a combined algorithm

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Journal of Systems Engineering and Electronics 2012年第1期23卷 88-98页

作者： jianghan zhu Lining Zhang Dishan qiu Haoping Li Science and Technology on Information Systems Engineering Laboratory National University of Defense Technology Changsha 410073 P. R. China Northern Electronic Equipment Institute Beijing 100191 P. R. China

Task scheduling for electro-magnetic detection satellite is a typical combinatorial optimization problem. The count of constraints that need to be taken into account is of large scale. An algorithm combined integer programming with constraint programming is presented. This algorithm is deployed in this problem through two steps. The first step is to decompose the original problem into master and sub-problem using the logic-based Benders decomposition; then a circus combines master and sub-problem solving process together, and the connection between them is general Benders cut. This hybrid algorithm is tested by a set of derived experiments. The result is compared with corresponding outcomes generated by the strength Pareto evolutionary algorithm and the pure constraint programming solver GECODE, which is an open source software. These tests and comparisons yield promising effect.

关键词： task scheduling combined algorithm logic-based Benders decomposition combinatorial optimization constraint programming (CP).

NYFR output pulse radar signal TOA analysis using extended Fourier transform and its TOA estimation

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Journal of Systems Engineering and Electronics 2017年第2期28卷 212-223页

作者： Zhaoyang qiu Pei Wang Jun zhu Bin Tang School of Electronic Engineering University of Electronic Science and Technology of China Chengdu 611731 China

Nyquist folding receiver (NYFR) is a typical wideband analog-to-information architecture. Focusing on the non-cooperative receiving, the pulse radar signal intercepted by the NYFR in time domain is analyzed. The NYFR outputs under different input conditions are investigated based on the extended Fourier transform (EFT) and the sampling theorem. Combining with the characteristic of the NYFR output in time domain, a new time of arrival (TOA) estimation method based on the energy envelope and the wavelet transform is proposed. The proposed estimation method can be adapted for the non-cooperative situation. It has no requirement for prior information to determine the threshold and is not necessary to transform the signal into baseband. Simulation results prove the correctness of the NYFR output expressions and show the efficacy of the proposed estimation method. © 2017 Beijing Institute of Aerospace Information.

关键词： Fourier transforms Radar Time domain analysis Wavelet transforms

Removal of lead from aqueous solution by hydroxyapatite/ manganese dioxide composite

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Frontiers of Environmental Science & Engineering 2016年第1期10卷 28-36页

作者： Lijing DONG Zhiliang zhu Yanling qiu jianfu ZHAO Key Laboratory of Yangtze River Water Environment Ministry of Education Shanghai 200092 China Environmental Monitoring Centre of Changzhou Changzhou 213000 China State Key Laboratory of Pollution Control and Resource Reuse Tongji University Shanghai 200092 China

A novel composite adsorbent, hydroxyapatite/ manganese dioxide （HAp/MnO2）, has been developed for the purpose of removing lead ions from aqueous solutions. The combination of HAp with MnO2 is meant to increase its adsorption capacity. Various factors that may affect the adsorption efficiency, including solution pH, coexistent substances such as humic acid and competing cations （Ca2＋, Mg2＋）, initial solute concentration, and the duration of the reaction, have been investigated. Using this composite adsorbent, solution pH and coexistent calcium or magnesium cations were found to have no significant influence on the removal of lead ions under the experi- mental conditions. The adsorption equilibrium was described well by the Langmuir isotherm model, and the calculated maximum adsorption capacity was 769 mg. gl. The sorption processes obeyed the pseudo-second-order kinetics model. The experimental results indicate that HAp/MnO2 composite may be an effective adsorbent for the removal of lead ions from aqueous solutions.

关键词： manganese dioxide hydroxyapatite lead,adsorption composite materials

Synthesis of mesoporous Cu/Mg/Fe layered double hydroxide and its adsorption performance for arsenate in aqueous solutions

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Journal of Environmental Sciences 2013年第5期25卷 944-953页

作者： Yanwei Guo Zhiliang zhu Yanling qiu jianfu Zhao State Key Laboratory of Pollution Control and Resource Reuse Tongji University Key Laboratory of Yangtze River Water Environment Ministry of EducationTongji University

The mesoporous Cu/Mg/Fe layered double hydroxide（Cu/Mg/Fe-LDH） with carbonate intercalation was synthesized and used for the removal of arsenate from aqueous *** Cu/Mg/Fe-LDH was characterized by Fourier transform infrared spectrometry,X-ray diffraction crystallography,scanning electron microscopy,X-ray photoelectron spectroscopy and *** of various physico-chemical parameters such as pH,adsorbent dosage,contact time and initial arsenate concentration on the adsorption of arsenate onto Cu/Mg/Fe-LDH were *** showed that it was efficient for the removal of arsenate,and the removal efficiency of arsenate increased with the increment of the adsorbent dosage,while the arsenate adsorption capacity decreased with increase of initial pH from 3 to *** adsorption isotherms can be well described by the Langmuir model with R 2 〉 *** adsorption kinetics followed the pseudo second-order kinetic *** ions such as HPO42-,CO32-,SO42and NO3could compete with arsenate for adsorption sites on the Cu/Mg/*** adsorption of arsenate on the adsorbent can be mainly attributed to the ion exchange *** was found that the synthesized Cu/Mg/Fe-LDH can reduce the arsenate concentration down to a final level of 〈 10 μg/L under the experimental conditions,and makes it a potential material for the decontamination of arsenate polluted water.

关键词： arsenate adsorption mesoporous layered double hydroxide anion exchange

Sparse Signal Recovery via Exponential Metric Approximation

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Tsinghua Science and Technology 2017年第1期22卷 104-111页

作者： jian Pan Jun Tang Wei zhu Department of Electronic Engineering Tsinghua University Beijing 100084China

Sparse signal recovery problems are common in parameter estimation, image processing, pattern recognition, and so on. The problem of recovering a sparse signal representation from a signal dictionary might be classified as a linear constraint l_0-quasinorm minimization problem, which is thought to be a Non-deterministic Polynomial-time（NP）-hard problem. Although several approximation methods have been developed to solve this problem via convex relaxation, researchers find the nonconvex methods to be more efficient in solving sparse recovery problems than convex methods. In this paper a nonconvex Exponential Metric Approximation（EMA）method is proposed to solve the sparse signal recovery problem. Our proposed EMA method aims to minimize a nonconvex negative exponential metric function to attain the sparse approximation and, with proper transformation,solve the problem via Difference Convex（DC） programming. Numerical simulations show that exponential metric function approximation yields better sparse recovery performance than other methods, and our proposed EMA-DC method is an efficient way to recover the sparse signals that are buried in noise.

关键词： sparse recovery exponential metric approximation sparsity tolerance DC optimization signal-to-noiseratio

Grain boundary segregation of minor arsenic and nitrogen at elevated temperatures in a microalloyed steel

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International Journal of Minerals,Metallurgy and Materials 2012年第5期19卷 399-403页

作者： Yuan-zhi zhu Zhe zhu jian-ping Xu The Key Laboratory of the Ministry of Education of China for Ferrous Metallurgy and Resources Utilization Wulaan University of Science and Technology Wuhan430081 China School of Materials and Metallurgy Wuhan University of Science and Technology Wuhan 430081 China

Auger electron spectroscopy （AES） was used to investigate the grain boundary segregation of arsenic and nitrogen in a kind of microalloyed steel produced by a compact strip production （CSP） technology at 950 to 1100℃, which are similar to the hot working temperature of the steel on a CSP production line. It was discovered that arsenic segregated on grain boundaries when the steel was annealed at 950℃ for 2 h. When the annealing temperature increased to 1100℃, arsenic was also found to have segregated on grain boundaries in the early annealing stage, for instance, within the first 5 min annealing time. However, if the holding time of the steel at this temperature increased to 2 h, arsenic diffused away from grain boundaries into the matrix again. Nitrogen was not found to have segregated on grain boundaries when the steel was annealed at a relatively low temperature, such as 950℃. But when the annealing temperature increased to 1100℃, nitrogen was detected to have segregated at grain boundaries in the steel.

关键词： alloy steel arsenic nitrogen segregation grain boundaries