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Preparation and Degradation Phenol Characterization of Ti/SnO_2-Sb-Mo Electrode Doped with Different Contents of Molybdenum

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Journal of Materials Science & Technology 2015年第5期31卷 473-478页

作者： jiyan Liang Cong Geng Dan Li Li Cui Xin Wang Department of Chemical & Environmental Engineering School of ScienceShenyang University of Technology

The Ti/SnO2-Sb-Mo electrodes doped with different molar ratios of molybdenum（Mo） were prepared by sol—gel method in order to investigate the effect of Mo on the characterization of Ti/SnO2-Sb—Mo electrodes.X-ray diffraction（XRD）,field-emission scanning electron microscopy（FE-SEM）,energy dispersive spectrometry（EDS）,and linear scanning voltammetry（LSV） were used to scrutinize the coating material and the electrochemical *** concentration of phenol,the value of total organic carbon（TOC）,the mineralization current efficiency（MCE） and the ultraviolet—visible spectroscopy（UV-Vis） spectrum of phenol solution were measured over the electrochemical degradation process of phenol to confirm the phenol degradation characterization of Ti/SnO2-Sb-Mo *** showed that the electrode at the Mo content of 1 at.%provided optimal catalytic activity for phenol degradation and the longest life *** removal percentage of phenol and TOC were 99.62%and82.67%,*** Ti/SnO2-Sb-Mo electrode with 1 at.%of Mo reached maximum MCE of phenol *** kinetic investigation of phenol and TOC degradation displayed the pseudo-first order reaction *** Ti/SnO2-Sb-Mo electrode coating with 7 at.%Mo presented the highest oxygen evolution overpotential,indicating the diverse effects for different Mo molar ratio doping.

关键词： Molybdenum Antimony doped tin oxide electrode Sol-

Synthesis of Quaternary α-Hydroxy Phosphonates via Direct Hydroxylation of Phosphonate Compounds

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Chinese Journal of Chemistry 2015年第5期33卷 559-562页

作者： jiyan Liu Wei Wang Rui Wang Lijun Gu Key Laboratory of Chemistry in Ethnic Medicinal Resources State Ethnic Affairs Commission&Ministry of EducationYunnan Minzu UniversityKunmingYunnan 650500China

It was found for the first time that Cs_(2)CO_(3) serves as highly efficient catalyst for the direct hydroxylation reactions of phosphonates under mild *** reaction provides an efficient approach to quaternaryα-hydro... 详细信息

关键词： quaternaryα-hydroxy phosphonates molecular oxygen direct hydroxylation

VNF-FG design and VNF placement for 5G mobile networks

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Science China(Information Sciences) 2017年第4期60卷 17-31页

作者： Jiuyue CAO Yan ZHANG Wei AN Xin CHEN jiyan SUN Yanni HAN State Key Laboratory of Information Security Institute of Information EngineeringChinese Academy of Sciences

Network function virtualization(NFV) is envisioned as one of the critical technologies in 5thGeneration(5G) mobile networks. This paper investigates the virtual network function forwarding graph(VNFFG) design and virtual network function(VNF) placement for 5G mobile networks. We first propose a two-step method composed of flow designing and flow combining for generating VNF-FGs according to network service requests. For mapping VNFs in the generated VNF-FG to physical resources, we then modify the hybrid NFV environment with introducing more types of physical nodes and mapping modes for the sake of completeness and practicality, and formulate the VNF placement optimization problem for achieving lower bandwidth consumption and lower maximum link utilization simultaneously. To resolve this problem, four genetic algorithms are proposed on the basis of the frameworks of two existing algorithms(multiple objective genetic algorithm and improved non-dominated sorting genetic algorithm). Simulation results show that Greedy-NSGA-II achieves the best performance among our four algorithms. Compared with three non-genetic algorithms(random, backtracking mapping and service chains deployment with affiliation-aware), Greedy-NSGA-II reduces 97.04%, 87.76% and88.42% of the average total bandwidth consumption, respectively, and achieves only 13.81%, 25.04% and 25.41%of the average maximum link utilization, respectively. Moreover, using our VNF-FG design method and GreedyNSGA-II together can also reduce the total bandwidth consumption remarkably.

关键词： network function virtualization VNF-FG design VNF placement multi-objective optimization genetic algorithm

Development and Tests of ZW-126/D2000-40 Vacuum Circuit Breakers with Controlled Switching Technology

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CSEE Journal of Power and Energy Systems 2022年第1期8卷 249-257页

作者： Yu Tian Jiayuan Xu Yuan Deng Yongxing Wang Enyuan Dong jiyan Zou Dalian University of Technology Dalian 116024China State Grid Pinggao Group Pingdingshan 467001China

A ZW-126/D2000-40 type single-break vacuum circuit breaker(VCB)with controlled switching technology is designed and produced in this *** results of type tests based on IEC and GB standards are presented.A 126 kV singlebreak vacuum interrupter(VI)with 3/4 coil axial magnetic field(AMF)contacts is used in the VCB,which can interrupt short currents of 40 *** external insulation of the VI is provided by SF_(6) at 0.1 *** order to match the 126 kV single-break VI and controlled switching device,a long-stroke electro-magnetic force actuator(EMFA)with 16 kN closing holding force and 3.5 m/s average opening speed is ***,a position tracking controlled switching device based on closed-loop control using the technology of a fuzzy control algorithm and pulse width modulation is applied to the controlled switching *** device is applied to control the coil current of EMFA and the electromagnetic force,so as to control the EMFA to follow the ideal position *** type tests of 126 kV VCB are all passed according to the IEC62271-100 and GB1984-2014,including dielectric tests,basic short-circuit tests,shortline fault tests,out-of-phase tests,*** strong capacitive current breaking capacity and mechanical strength of the VCB are proved by the capacitive current switching test of class C2,electrical endurance test of class E2 and mechanical endurance test of class *** electromagnetic compatibility(EMC)tests are passed according to the *** controlled switching test of capacitive current was successful according to IEC62271-302 and GB/T30846-2014,and the controlled switching accuracy is less than±0.5 *** test results show that the VCB has excellent performance,which has broad application prospects in special occasions at a 126 kV voltage level,such as a switching capacitor and no-load transformer,etc.

关键词： Controlled switching electro-magnetic force actuator(EMFA) single-break type test vacuum circuit breaker(VCB)

Nonoscillation for a Second Order Linear Delay Differential Equation with Impulses

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Acta Mathematicae Applicatae Sinica 2004年第1期20卷 101-114页

作者： Yan-lingTian Pei-xuanWeng Jin-jiyan DepartmentofMathematics.SouthChinaNormalUniversity Guangzhou510631China DepartmentofComputerSciences SouthChinaNormalUniversityGuangzhou510631China

A group of necessary and sufficient conditions for the nonoscillation of a second order linear delay equation with impulses

关键词： nonoscillation impulse linear delay differential equation boundedness

Butyltin compounds in vinegar collected in Beijing:Species distribution and source investigation

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Science China Chemistry 2012年第2期55卷 323-328页

作者： CUI ZongYan ZHANG KeGang ZHOU QunFang LIU jiyan JIANG GuiBin State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China

Forty-eight vinegar samples including white vinegar, rice vinegar and mature vinegar were collected from several markets in Beijing. Butyltin compounds were determined by headspace solid-phase microextraction coupled with gas chromatography and flame photometric detector after in situ ethylation with sodium tetraethylborate. Butyltin species were detected in sixteen vinegar samples and ranged from 0.012 to 14.10 lag Sn L 1. The detection rate of white vinegar is higher than that of rice vinegar and mature vinegar. Vinegar samples with relatively high butyltin concentration (〉1.5 μg Sn L-1) were those stored in plastic bags, indicating that the plastic bag was one of the possible sources of butyltin contamination. This was further confirmed by the leaching experiments of three selected plastic bags, and monobutyltin was detected in the leaching solvents. According to the estimation, the average daily intake of total butyltin compounds through vinegar consumption is about 0.04 ng Sn/kg b.w., much lower than the Tolerable Daily Intake (TDI) of 100 ng Sn/kg b.w. set by the European Food Safety Authority (EFSA).

关键词： butyltin compounds vinegar headspace solid-phase microextraction gas chromatography-flame photometric detection

Filtering detecting signal of rockbolt with harmonic wavelet

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Mining Science and Technology 2010年第3期20卷 411-414页

作者： WANG jiyan ZHAO Yucheng YAO Banghua XU Jinhai School of Mechanics & Civil Engineering China University of Mining & Technology Xuzhou 221008 China School of Mines China University of Mining & Technology Xuzhou 221008 China

Harmonic wavelets not only possess the traditional advantages of a wavelet function,they also have other merits such as clear expressions,more flexible time-frequency divisions,a simple transformation algorithm,a finer box-like frequency spectrum and *** the frequency distribution characteristics of the nondestructive testing signals from a rockbolt support system and based on the discrete harmonic wavelet transformation theory,we have effectively abstracted signals from frequency ranges concerned by removing useless high and low frequency signals from the testing signals of the rockbolt support system and obtained filtered signals with a reconstruction algorithm of harmonic ***,we applied the harmonic wavelet transformation in filtering analog signals and measured response signals of *** results indicate that harmonic wavelets also have excellent filtering characteristics.

关键词： rockbolt support system testing harmonic wavelet filtering

Synthesis and Biodegradation of St-g-poly(MMA-co-VAc) Initiated by Manganic Pyrophosphate

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Chemical Research in Chinese Universities 2004年第2期20卷 232-235页

作者： ZHULin-hui CHENMi-feng jiyan XIAHai-ping DINGMa-tai CollegeofChemistryandChemicalEngineering XiamenUniversityXiamen361005P.R.China CollegeofChemistryandEnvironmentalScience KeyLaboratoryofEnvironmentalScienceandTechnologyofHighEducationinHenanProvinceHenanNormalUniversityXinxiang453002P.R.China

Methyl methacrylate(MMA) and vinyl acetate(VAc) were grafted onto corn starch with manganic pyrophosphate{[Mn(H 2P 2O 7) 3] 3-} as the initiator and water as the reaction medium. The influences of reaction conditions, including pH value, initiator concentration, monomer concentration and its composition, on percent grafting and grafting efficiency were investigated. The graft copolymer was characterized by means of IR spectroscopy, scanning electron micrograph(SEM) and 1H NMR spectroscopy. The biodegradation experiment showed that the degradation of corn starch-g-poly(MMA-co-VAc) was mainly from starch. However, after poly VAc in the side chain was transformed into poly vinyl alcohol(PVA), both starch and the grafted side chain could be degraded completely.

关键词： Starch Graft copolymerization Manganic pyrophosphate Biodegradation

Geochemical Characteristics and Occurrence States of RE Element in Phosphorite in Xinhua , Zhijin, Guizhou

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Journal of Rare Earths 2004年第z1期22卷 320-324页

作者： Zhang Jie Zhang Qin Chen Dailiang Cheng jiyan Zhu Lei Chengdu University of Technology Geosciences College Chengdu 610059 China Guizhou University College of Resources and Environment Guiyang 550003 China Guizhou University College of Resources and Environment Guiyang 550003 China GuiZhou Geological Survey Academy Ministry of Chemical Industry Zunyi 563100 China Guizhou University College of Resources and Environment Guiyang 550003 China Guizhou University College of Resources and Environment Guiyang 550003 China

The RE and composition of trace elements analysis show that phosphorite-ores are rich in ∑ RE concentration generally in Xinhua, *** phosphorites were measured to gather LRE and HRE *** is higher than other *** phosphorite has enriched Y, La and Nd chemical *** are leading characteristics of concentrated La, LRE and Y, *** chondrite-normalized RE element patterns of the Xinhua dolomitic phosphorite distribute mode for rightwards type to one side of the ***/HRE ＞ 1, (La/Sm)N ＞ (Gd/Yb)N, and all indicate that LRE content is higher than *** test mode of chemical analysis of single mineral, chemistry phase analysis, scan electric analysis and micro-electronics probe analysis were *** chart of EDAX showed that there was representative element-Y(RE) in *** was no independent mineral of the *** is show that part of the few rare earth chemical element is adsorbed by the clay mineral, much for the type of quality isomorphic form exist in the apatite crystal structure of phosphorite inside.

关键词： occurrence of RE phosphorites in Xinhua rare earths