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Chinese Chemical Letters 2014年第11期25卷 1461-1465页

作者： Feng Li Chun-Shan Lu Xiao-Nian Li Institute of industrial Catalysis of Zhejiang University of Technology State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology

The effect of the amount of precipitant ammonia on the Cu0/Cu＋ratio of Cu/Si O2 prepared by the deposition–precipitation method is investigated. Species at different preparation stages, resulted from the amount of ammonia used, are identified by the XRD and FTIR techniques. Chrysocolla together with either copper nitrate hydroxide or copper hydroxide coexist in the uncalcined catalysts. Upon calcination, the latter two species are converted to Cu O particles while chrysocolla remains. Following reduction, Cu O is transformed to metallic Cu and chrysocolla is converted to Cu2 O. The value of Cu0/Cu＋ratio can be evaluated using the peak areas in their TPR profiles. Hydrogenation of dimethyl oxalate（DMO） to ethylene glycol（EG） shows that the selectivity of EG depends on the Cu0/Cu＋ratio. Catalyst prepared with the addition of ammonia solution at n（NH3）/n（Cu2＋） = 0.9 for precipitation–deposition gains a more suitable Cu0/Cu＋ratio upon reduction and thus has a higher selectivity for EG.

关键词： Amount of ammonia Deposition–precipitation Chrysocolla Copper nitrate hydroxide Copper hydroxide DMO hydrogenation

Mechanism of high temperature reduction on iron carbide preparation with low-grade siderite

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Journal of Iron and Steel research International 2022年第9期29卷 1357-1367页

作者： Dong Chen Ya-nan Lv Wei Zhao Fei-bao Wu Wei-ang Ying School of Iron and Steel Soochow UniversitySuzhou 215021JiangsuChina Department of Mechanical and Electrical Engineering Suzhou Institute of Industrial TechnologySuzhou 215104JiangsuChina

The carburization roasting followed by magnetic separation is a feasible method to utilize low-grade siderite *** order to enhance the carburization efficiency and separation effciency,high temperature reduction was carried out,and its mechanism was demonstrated by measuring carburization index,phase change,and microstructure under a carbon-sulfur infrared analyzer,an X-ray diffractometer,and a metallurgical *** results show that both the carburization effciency of siderite pellet and the separation efficiency of iron carbide from gangue are very ***,high temperature reduction is a useful way to enhance the carburization efficiency,as it can accelerate the reduction reaction rate and carburization reaction ***,high temperature reduction can improve the growth of iron carbide particle,promote the carburization efficiency,and strengthen the sodium modification reactions,thereby greatly accelerating the separation efficiency of iron carbide and *** the siderite pellets were reduced at 1050℃ for 90 min and carburized at 650℃ for 120 min,the carburization index of carburized pellets reached *** magnetic separation treatment,an electric furnace burden assaying 83.12 wt.%Fe and 6.96 wt.%C was prepared,and the corresponding iron recovery rate was 95.43%.The high temperature reduction is promisingly adopted to promote the utilization of low-grade siderite ores using carburization-magnetic separation technology.

关键词： Siderite High temperature reduction Carburization-Separation Iron carbide

Topological Structure of US Flight Network based on Complex Network Theory

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Transactions of Nanjing University of Aeronautics and Astronautics 2015年第5期32卷 555-559页

作者：李善梅徐肖豪王飞王兴隆 Air Traffic Management research base Civil Aviation University of China

US flight network,composed of 285airports(nodes)and 3 971flights(edges)is studied.A static network model and a dynamic network model of US flight network are ***,the characteristics of static network are *** finds that such a network is a″small-world″and″scale-free″*** cumulative degree distributions of weighted network and unweighted network follow″Double Pareto Law″.And the degree exponent of weighted network is smaller than unweighted *** average shortest-path length is 2.368 9,which is smaller than previous *** clustering coefficient of unweighted network is 0.637 1and of weighted network is 0.653 6,which are both bigger than previous *** correlation of degree,unweighted clustering coefficient and weighted clustering coefficient are also ***,the characteristics of dynamic network are *** structure of flight network is changing as the time goes by on a *** rush hours,the network′s character of″scale-free″is stronger than other *** then the relationships of topological structures and congestion effects are addressed.

关键词： complex network scale-free small-world congestion effect

Reduced nitrogen application rate with dense planting improves rice grain yield and nitrogen use efficiency: A case study in east China

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The Crop Journal 2021年第4期9卷 954-961页

作者： Huanhe Wei Tianyao Meng Jialin Ge Xubin Zhang Tianyi Shi Enhao Ding Yu Lu Xinyue Li Yuan Tao Yinglong Chen Min Li Qigen Dai jiangsu Key Laboratory of Crop Cultivation and Physiology/jiangsu Key Laboratory of Crop Genetics and Physiology/jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops/research Institute of Rice industrial Engineering Technology Yangzhou UniversityYangzhou 225009JiangsuChina Institutes of Agricultural Science and Technology Development/Joint International research Laboratory of Agriculture and Agri-Product Safety The Ministry of Education of ChinaYangzhou UniversityYangzhou 225009JiangsuChina Rice research Institute of Guizhou Guiyang 550006GuizhouChina

Dense planting could be a feasible method for reducing nitrogen(N) application rates without compromising rice grain yield in northeast and central China. It is still unclear whether reduced N application with dense planting(RNDP) can achieve higher rice yield and N use efficiency(NUE) in jiangsu, east China. Three japonica inbred rice(JI) and three indica hybrid rice(IH) cultivars were grown in a field experiment. Their grain yield, NUE, and related traits were compared under two cultivation treatments:conventional high-yielding practice(CHYP) and RNDP. JI showed similar yields under the two treatments,while IH showed lower yield under RNDP than under CHYP, and the partial factor productivity of N and N use efficiency for grain yield increased(P jiangsu. For JI, the increased panicles per m2, sink-filling efficiency, harvest index, and NSC remobilization after heading under RNDP contributed to a grain yield similar to that under CHYP.

关键词： Japonica inbred rice Grain yield Nitrogen use efficiency Reduced nitrogen rate Dense planting

Induction of Chromosomal Aberrations by Propoxur in Mouse Bone Marrow Cells

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Biomedical and Environmental Sciences 1999年第4期12卷 292-295页

作者： R. C. AGRAWAL(Laboratory of Environmental Carcinognesis, industrial Toxicology researchCentre, Post Box No. 80, Mahatma Gandhi Marg, Lucknow, India) industrial Toxicology research Centre 印度

Propoxur is a widely used dithiocarbamate insecticide. In this study, the clastogenic effect of propoxur has been evaluated using chromosomal aberration assay in mouse bone marrow cells. Single i. p. administration of propoxur, at 25 mg/kg ***., a maximum tolerated dose (MTD) and 12 .5mg/kg *** (50% of MTD) have significantly induced different types of aberrations after 24 h of treatment. The aberrations were dose and time dependent and reached a maximum after 24 h of exposure. The sresult suggest a genotoxic potential of propoxur.

关键词： Chromosome Aberrations Animals Bone Marrow Cells DNA Damage Insecticides Male Mice Mutagenicity Tests Propoxur

Selective hydrogenation of dimethyl maleate to tetrahydrofuran over Cu/SiO_2 catalyst:Effect of Cu^+ on the catalytic performance

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Chinese Chemical Letters 2015年第9期26卷 1150-1154页

作者： Xue-Qing Han Qun-Feng Zhang Feng Feng Chun-Shan Lu Lei Ma Xiao-Nian Li Institute of industrial Catalysis ofZhejiang University of Technology State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology

Cu/SiO2 catalysts prepared by different methods have been investigated focusing on the influence of Cu^＋on the catalytic *** composition,structure and copper valence state were characterized by means of BET,XRD,XPS,FTIR,*** was found that the Cu/SiO2 prepared by ammoniaevaporation（AE） method had much higher TOF value than that prepared by wetness-impregnation（WI）with the same THF *** higher TOF value was attributed to the coexistence of Cu^＋ and Cu^0species in the activated AE-Cu/*** only Cu° species existing in the activated Wl-Cu/*** suggest that Cu^＋ can adsorb and polarize the C=0 bond of *** is concluded that Cu°could be the main active site and the synergistic effect between Cu^0 and Cu^＋ could contribute to hydrogenation of DMM to THF.

关键词： Dimethyl maleate Tetrahydrofuran Copper phyllosilicate Silica-supported copper Copper valence state

One-pot synthesis of nitrogen and sulfur co-doped activated carbon supported AuCl_3 as efficient catalysts for acetylene hydrochlorination

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Chinese Chemical Letters 2016年第9期27卷 1567-1571页

作者： Xiao-Xia Di Jia Zhao Yi Yu Xiao-Long Xu Shan-Chuan Gu Hai-Hua He Tong-Tong Zhang Xiao-Nian Li Institute of industrial Catalysis of Zhejiang University of Technology State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology

Commercialization of acetylene hydrochlorination using AuCl3 catalysts has been impeded by its poor stability. We have been studying that nitrogen-modified Au/NAC catalyst delivered a stable performance which can improve acetylene hydrochlorination activity and has resistance to catalytic deactivation. Here we show that nitrogen and sulfur co-doped activated carbon supported AuCl3 catalyst worked as efficient catalysts for the hydrochlorination of acetylene to vinyl chloride. Au/NSAC catalyst demonstrated high activity comparative to Au/AC catalyst. Furthermore, it also delivered stable performance within the selectivity of acetylene, reaching more than 99.5%, and there was only a 3.3% C2H2 conversion loss after running for 12 h under the reaction conditions of a temperature of 180 C and a C2H2 hourly space velocity of 1480 h 1. The presence of the sulfur atoms may serve to immobilize/ anchor the Au and also help prevent reduction and sintering of the Au and hence improve the catalytic activity and stability. The excellent catalytic performance of the Au/NSAC catalyst demonstrated its potential as an alternative to mercury chloride catalysts for acetylene hydrochlorination.

关键词： Acetylene Hydrochlorination AuCl3 Nitrogen and sulfur co-doped

Improvement of the stability of Hg/AC catalysts by CsCl for the high-temperature hydrochlorination of acetylene

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Chinese Chemical Letters 2016年第6期27卷 822-826页

作者： Xiao-Long Xu Jia Zhao Chun-Shan Lu Tong-Tong Zhang Xiao-Xia Di Shan-Chuan Gu Xiao-Nian Li Institute of industrial Catalysis of Zhejiang University of Technology State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology

Activated carbon-supported mercuric chloride（HgCl2） is used as an industrial catalyst for acetylene hydrochlorination. However, the characteristic of easy sublimation of HgCl2 leads to the deactivation o the catalyst. Here, we showed that the thermal stability of the Hg/AC catalyst can be evidently improved when Cs Cl is added into the Hg/AC catalyst. Compared with the pure Hg/AC catalyst, the sublimation rate of HgCl2 from the Hg–Cs/AC catalyst decreased significantly and the Hg–Cs/AC catalyst showed bette catalytic activity and stability in the reaction. This promoting effect is related to the existence of cesium mercuric chlorides（CsxHgyCl（x＋2y）） highlighted by XRD, HR-TEM and EDX analyses. Thus, reacting HgCl2 with alkali chlorides to form alkali-mercuric chlorides may be a key to design highly efficient and thermally stable mercuric chloride catalyst for hydrochlorination reactions.

关键词： Cesium chloride Mercuric chloride Sublimation Hydrochlorination of acetylene Cesium–mercuric chlorides

Synthesized high-silica hierarchical porous ZSM-5 and optimization of its reaction conditions in benzene alkylation with methanol

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Chinese Chemical Letters 2019年第3期30卷 757-761页

作者： Jiayao Rui Jinghui Lyu Hualei Hu Qunfeng Zhang Qingtao Wang Xiaonian Li industrial Catalysis Institute of Zhejiang University of Technology State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology

In our present work, the high-silica hierarchical porous ZSM-5 with appropriate Br(o|¨)nsted acidity and hierarchical porous structure was synthesized by sol-gel method for continuously catalytic conversion of benzene alkylation with methanol to xylene. The effects of temperature, pressure, benzene/methanol molar ratio and weight hour space velocity(WHSV) on the catalytic performance of the catalyst were investigated as well. As a result, the high-silica hierarchical porous ZSM-5 showed great performance as the yield of xylene was up to 41.1% under the optimum reaction conditions(500 ℃,0.1 MPa,M_(benzene)/M_(methanol)= 1:1.5 and WHSV=4 h 1), while the selectivity to by-product, ethylbenzene, was well suppressed(below 0.1%). In addition, the catalyst structure and properties were characterized by the means of XRD, IR, TPD,SEM, TEM and N_2 physical adsorption technologies.

关键词： ZSM-5 Ethylbenzene Xylene Optimization Benzene alkylation

Evaluation of Cytogenetic Effects of Isoproturon on the Root Meristem Cells of Allium sativum

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Biomedical and Environmental Sciences 2001年第3期14卷 214-219页

作者： L. K. S. CHAUHAN, P. N. SAXENA, AND S. K. GUPTA1Cell Biology Section, industrial Toxicology research Centre, P. B. No. 80, M. G. Marg, Lucknow- 226001, India\ \ industrial Toxicology research Centre 印度 226001

Objective\ To validate the use of Allium sativum as a reliable test model for genotoxicity, isoproturon, a substituted phenylalkylurea herbicide, was evaluated on the root meristem cells by this plant system. Method\ Test concentrations were selected by determining EC50 and root tips were exposed to various concentrations for 6 or 24 hr. EC50 concentration was calculated to be 70.8 ppm for the root growth. In addition to root growth retardation exposure to isoproturon induced morpholoogical changes like discolouration and stiffness of roots. Results\ Exposure to various experimental concentrations of isoproturon (35-280 ppm), including EC50, significantly and dose-dependently inhibited the mitotic index and induced chromosome breaks/mitotic aberrations at 6 or 24 hr. Conclusion\ The frequency of aberrations was found to be decreased in a dose dependant manner at 24 or 48 hr post exposure, however in comparison of control cells the frequency of aberrations was considerably high which indicates genotoxicity potentials of isoproturon. Further, present study also suggests that Allium sativum is a sensitive, efficient, and reliable test system for measuring the genotoxicity potential of environmental chemicals.

关键词： Phenylurea Compounds Chromosome Aberrations DNA Damage Dose-Response Relationship, Drug Garlic Herbicides Lethal Dose 50 Methylurea Compounds Mitosis Mutagenicity Tests Plant Roots Sensitivity and Specificity