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Pointwise characterization for combinations of Szász-Mirakjan operators

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Applied Mathematics(A Journal of Chinese Universities) 2008年第2期23卷 202-212页

作者： XIE Lin-sen shi Zhong-rui Dept. of Math. Shanghai Univ. Shanghai 200444 China Dept. of Math. Lishui Univ. Lishui 323000 China

The purpose of this paper is to characterize the pointwise rate of convergence for the combinations of Szász-Mirakjan operators using Ditzian-Totik modulus of smoothness.

关键词： Szász-Mirakjan operator combination pointwise approximation.

Rice variety improvement and the contribution of foreign germplasms in China

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Journal of Integrative Agriculture 2017年第10期16卷 2337-2345页

作者： shi Xiao-hua HU rui-fa School of Management and Economics Beijing Institute of Technology Beijing 100081 P.R.China Henan Institute of Science and Technology Xinxiang 453003 P.R. China

The introduction and use of foreign germplasms have played an important role in the improvement of crop varieties in China. Based on published materials and scientist interviews, we collected data on the sown area, morphological characteristics, and pedigree of the popular rice varieties grown in the 15 major rice production provinces and 1 autonomous region in China, from 1982 to 2011. Results showed that China＇s scientists developed the largest number of rice varieties worldwide, and that rice yield potential and grain quality have substantiality improved during the studied period. In contrast, resistance of newly-released varieties to diseases and insect pests has decreased since the 1990s. Germplasms from the Interna- tional Rice Research Institute （IRRI） and from Japan have contributed 16.4 and 11.2% of genetic materials to China＇s rice varieties developed between 1982 and 2011, respectively. While IRRI＇s materials contributed to the improvement of yield potential, growth duration, and blast and bacterial blight resistance, Japanese materials contributed to the improvement of grain quality. Materials from other countries contributed to the improvement of resistance to diseases and insect pests, particularly to rice blast disease, brown planthoppers, white-backed planthoppers, and striped stem borers.

关键词： rice foreign germpiasm variety improvement China

Lifetime prediction and failure analysis of organic coatings by EIS

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 455-458页

作者： YAN rui WU Hang MA shi-ning XU Bin-shi Surface Engineering Research Institute of CMES Chinese Mechanical Engineering Society Beijing 100072 China Surface Engineering Research Institute of CMES Chinese Mechanical Engineering Society Beijing 100072 China Surface Engineering Research Institute of CMES Chinese Mechanical Engineering Society Beijing 100072 China Surface Engineering Research Institute of CMES Chinese Mechanical Engineering Society Beijing 100072 China

Organic coatings are widely used to control the corrosion of steel structure. The anticorrosive property of these coatings depends on their barrier properties, making a separation between the corrosive medium and the substrate. But unavoidable completely small pores, cracks and other defects in organic coatings may cause ions, water, gases, and other corrosive species penetrate and distribute in the coatings, causing accumulation and swelling of coatings, so leading to the degradation of coatings. In addition, water affects the permeation of oxygen and other corrosive medium, consequently the presence of such substances at coating-metal interface promotes corrosion of metal substrate. So the absorbability of the coatings to water may be one of the most important factors in undercoating corrosion. In recent years, electrochemical impedance spectroscopy (EIS) has been established and frequently used as a non-destructive testing method for assessing the performance of organic coatings, especially for the determination of the water content in organic coatings, since the capacitance of the coatings is sensitive to the penetration of water. So from EIS it can extract a wealth of information on the electrochemical corrosion of coated steels, especially, it can be utilized to assess organic coatings used under particular surroundings. The principle, methods and application of EIS on evaluating life-span and analyzing failure mechanism of organic coatings are also introduced briefly. Combining other analysis techniques such as XRD, SEM and FTIR with electrochemical technique, it will blaze a way in studying degradation mechanism of organic coatings and estimating their lifetime.

关键词： organic coatings lifetime prediction failure analysis electrochemical impedance spectro scopy

Preparation of large size ZTA ceramics with eccentric circle shape by microwave sintering

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Journal of Advanced Ceramics 2016年第4期5卷 291-297页

作者： Yongqiang CHEN Bingbing FAN Gang shao rui ZHANG Zhengzhou University of Aeronautics Henan 450015 ChinaSchool of Materials Science and Engineering Zhengzhou University Henan 450001 China School of Materials Science and Engineering Zhengzhou University Henan 450001 ChinaSinosteel Luoyang Institute of Refractories Research Co. Ltd. Henan 471039 China School of Materials Science and Engineering Zhengzhou University Henan 450001 China

Ultra-large zirconia toughened alumina (ZTA,mass ratio of Al2O3 and ZrO2 is 78∶22) ceramics with eccentric circle shape were successfully sintered by microwave sintering with a multi-mode cavity at 2.45 *** dimension of ZTA ceramics (green body) is 165 mm (outer diameter) × 25 mm (thickness).The optimized sintering temperature of microwave sintering is about 1500 ℃ for 30 min,and the total sintering time is about 4 h which is much shorter than that of conventional *** auxiliary-heating insulation device was designed based on the principle of local caloric compensation to guarantee the intact sintered *** the increasing of sintering temperature,more and more microwave energy is absorbed within the entire sample,volumetric densification performs,and phases shift from m-ZrO2 phase to t-ZrO2 phase and cause Al2O3 grain growth.

关键词： large size ZTA ceramics eccentric circle shape microwave sintering local caloric compensation

Pointwise Simultaneous Approximation by Combinations of Baskakov Operators

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Acta Mathematica Sinica,English Series 2007年第5期23卷 935-944页

作者： Lin Sen XIE Zhong rui shi Department of Mathematics Shanghai University Shanghai 200444 P. R. China Department of Mathematics Lishui University Lishui 323000 P. R. China

In this paper, we investigate the relation between the rate of convergence for the derivatives of the combinations of Baskakov operators and the smoothness for the derivatives of the functions approximated. We give some direct and inverse results on pointwise simultaneous approximation by the combinations of Baskakov operators. We also give a new equivalent result on pointwise approximation by these operators.

关键词： Baskakov operator combination simultaneous approximation modulus of smoothness

Catalytic decomposition of low level ozone with gold nanoparticles supported on activated carbon

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Frontiers of Environmental Science & Engineering 2009年第3期3卷 281-288页

作者： Pengyi ZHANG Bo ZHANG rui shi Department of Environmental Science and Engineering Tsinghua UniversityBeijing 100084China

Highly dispersed gold nanoparticles were supported on coal-based activated carbon(AC)by a sol immobilization method and were used to investigate their catalytic activity for low-level ozone decomposition at ambient *** adsorption-desorption,scanning electron microscope(SEM),and X-ray photoelectron spectroscopy(XPS)were used to characterize the catalysts before and after ozone *** results showed that the supported gold nanoparticles prepared with microwave heating were much smaller and more uniformly dispersed on the activated carbon than those prepared with traditional conduction heating,exhibiting higher catalytic activity for ozone *** pH values of gold precursor solution significantly influenced the catalytic activity of supported gold for ozone decomposition,and the best pH value was *** the case of space velocity of 120000 h–1,inlet ozone concentration of 50 mg/m3,and relative humidity of 45%,the Au/AC catalyst maintained the ozone removal ratio at 90.7%after 2500 *** being used for ozone decomposition,the surface carbon of the catalyst was partly oxidized and the oxygen content increased accordingly,while its specific surface area and pore volume only decreased a *** was mainly catalytically decomposed by the gold nanoparticles supported on the activated carbon.

关键词： ozone decomposition activated carbon gold nanoparticles catalysis sodium citrate microwave

Contributions of climate change to cereal yields in Tibet, 1993–2017

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Journal of Geographical Sciences 2022年第1期32卷 101-116页

作者： DING rui shi Wenjiao Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China

Climate change is a global environmental crisis, but there have been few studies of the effects of climate change on cereal yields on the Tibetan Plateau. We used data from meteorological stations and statistical yearbooks to assess the impacts of climate change on cereal yields in Tibet. Three types of statistical models were selected: fixed-effects model, first-difference models, and linear detrending models. We analyzed the impacts of climate change(including the minimum temperature, precipitation, growing degree days and solar radiation) on cereal yields in Tibet from 1993 to 2017 at the county, prefecture-level city, and autonomous region scales. The results showed that the sensitivity of cereal yields in Tibet to temperature(minimum temperature and growing degree days) was greater than their sensitivity to precipitation and solar radiation. The joint impacts of climate variables were positive, but the sensitivity and significance varied in different regions. The impacts of minimum temperature, precipitation, and solar radiation were positive in all cities, apart from the negative impacts of growing degree days on cereal yields in Lhasa. The impacts of climate trends on cereal yields in Tibet were positive and the results were in the range of 1.5%–4.8%. Among the three types of model, the fixed-effects model was the most robust and the linear detrending model performed better than the first-difference model. The robustness of the first-difference model decreased after adding the interaction terms between different climate variables. Our findings will help in implementing more spatially targeted agricultural adaptations to cope with the impacts of climate change on the agro-ecosystem of the Tibetan Plateau.

关键词： Tibetan Plateau climate change statistical model cereal yields

Physical and Mechanical Properties of Catalpa bungei Clones and Estimation of the Properties by Near-Infrared Spectroscopy

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Journal of Renewable Materials 2022年第12期10卷 3285-3302页

作者： rui Wang Lanlan shi Yurong Wang Research Institute of Wood Industry Chinese Academy of ForestryBeijing100091China

Air-dry density,modulus of rupture(MOR),modulus of elasticity(MOE),compressive strength parallel to grain,and hardness of Catalpa bungei clones were investigated in this study with feasibility of predicting these properties by near infrared(NIR)*** best candidate Luoqiu 3'has been selected from three clones based on wood physical and mechanical property *** values of wood physical and mechanical properties have been found in the corewood compared to the *** were significant positive correlations between the air-dry density and mechanical *** from Cross section for air dry density,compressive strength parallel to grain,and hardness yielded prediction models with better effects,along with the best MOR and MOE modeling effects resulted from average sections'spectra *** scatter correction(MSC)+Savitzky-Golay(S-G)smoothing method has been proved to be the most applicable *** addition,the predictions from five point sampling method were slightly better than three point ***,results suggest NIR spectroscopy was viable to predict the physical and mechanical properties of C bungei dones with methods developed in this study proved effective in preliminary screening.

关键词： C.bungei wood density mechanical properties near-infrared spectroscopy

Involvements of chloride ion in decolorization of Acid Orange 7 by activated peroxydisulfate or peroxymonosulfate oxidation

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Journal of Environmental Sciences 2011年第11期23卷 1799-1807页

作者： Ping Wang shiying Yang Liang Shan rui Niu Xueting shao Key Laboratory of Marine Environment and Ecology Ministry of EducationQingdao 266100China College of Environmental Science and Engineering Ocean University of ChinaQingdao 266100China Department of Civil and Structural Engineering The Hong Kong Polytechnic UniversityKowloonHong KongChina

The effects of chloride anion （Cl-）（up to 1.0 mol/L） on the decolorization of a model compound,azo dye Acid Orange 7 （AO7）,by sulfate radical （SO4-） based-peroxydisulfate （PS） or peroxymonosulfate （PMS） oxidation under various activated conditions （UV 254 nm /PS,Thermal （70°C/PS,UV 254 nm /PMS,Co 2＋ /PMS） were *** and NH4 ＋ were used as quenching reagents to determine the contributions of active chlorine species （dichloride radical （Cl2-.） and hypochlorous acid （HClO））.The results indicated that the effects of Cl- on the reaction mechanism were different under various activated *** UV/PS and Thermal/PS,the inhibition tendency became more clear as the Cl- concentration increased,probably due to the reaction between Cl- and SO4-.and the generation of Cl2-.or *** UV/PMS,Cl- did not exhibit inhibition when the concentration was below 0.1 mol/*** Cl- concentration reached to 1.0 mol/L,the decolorization rate of AO7 was,however,accelerated,possibly because PMS directly reacts with Cl- to form *** Co2＋ /PMS,Cl- exhibited a significant inhibiting effect even at low concentration （ 0.01 mol/L）.When Cl- concentration exceeded 0.1 mol/L,the activation of PMS by Co 2＋ was almost completely *** this condition,HClO maybe played a major role in decolorization of *** results implicated that chloride ion is an important factor in SO4-.-based degradation of organic contamination in chloride-containing water.

关键词： chloride anion activated peroxydisulfate oxidation activated peroxymonosulfate oxidation radicals decolorization