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In situ Analysis of Na and K in a Laminar Premixed Flame by Laser-induced Breakdown Spectroscopy

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Chemical Research in Chinese Universities 2013年第6期29卷 1149-1152页

作者： li Yu ZHANG Han-zhuang li Zhong-shan li hong-dong ZHANG Chun-wei HU Chang-hong College of Physics Jilin University Changchun 130012 P.R.China State Key Laboratory of Superhard Materials Jilin University Changchun 130012 P.R.China Division of Combustion Physics Lund University Lund Sweden

Laser-induced breakdown spectroscopy（liBS） was used to in situ monitor the concentration of alkali elements in combustion environments. Particular efforts were made to optimize the temporally resolved spectra of Na and K elements. Calibration curves were constructed by relating the intensities of the specific lines to the corres- ponding elemental concentrations. The detection limits of Na and K elements were found to be temperature- dependent. The results indicate that liBS can be a powerful tool for in situ monitoring Na and K concentrations in combustion environments.

关键词： Laser-induced breakdown spectroscopy(liBS) Alkali metal Solution-seeded Calibration curve

Histological and Ultrastructural Observation Reveals Significant Cellular Differences between Agrobacterium Transformed Embryogenic and Non-embryogenic Calli of Cotton

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Journal of Integrative Plant Biology 2009年第5期51卷 456-465页

作者： Hai-hong Shang Chuan-liang liu Chao-Jun Zhang Feng-lian li Wei-dong hong Fu-Guang li Key Laboratory of Cotton Genetic Improvement Ministry of Agriculture Chinese Cotton Research Institute Chinese Agricultural Academy of Sciences Anyang 455004 China

Over the past few decades genetic engineering has been applied to improve cotton breeding. Agrobacterium medicated transformation is nowadays widely used as an efficient approach to introduce exogenous genes into cotton for genetically modified organisms. However, it still needs to be improved for better transformation efficiency and higher embryogenic callus induction ratios. To research further the difference of mechanisms for morphogenesis between embryogenic callus and non-embryogenic callus, we carried out a systematical study on the histological and cellular ultrastructure of Agrobacterium transformed calli. Results showed that the embryogenic callus developed nodule-like structures, which were formed by small, tightly packed, hemispherical cells. The surface of some embryogenic callus was covered with a fibrilar-like structure named extracellular matrix. The cells of embryogenic calli had similar morphological characteristics. Organelles of embryogenic callus cells were located near the nucleus, and chloroplasts degraded to proplastid-like structures with some starch grains. In contrast, the non-embryogenic calli were covered by oval or sphere cells or small clusters of cells. It was observed that cells had vacuolation of cytoplasm and plastids with a well organized endomembrane system. This study aims to understand the mechanisms of embryogenic callus morphogenesis and to improve the efficiency of cotton transformation in future.

关键词： cell organization pattern chloroplasts embryogenic callus Gossypiurn hirsutum histological structure transformation ultrastructure

A novel derivative of geldanamycin and its antitumor activity

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Chinese Chemical Letters 2009年第4期20卷 391-392页

作者： liang li hong liu Xian dong Xu Yong Su Zhen Institute of Medicinal Biotechnology Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100050 China

A new derivative of geldanamycin was synthesized by introducing the 6-cinnamamido-hexyl-amino group into the 17-site of geldanamycin, a heat shock protein 90 （Hsp90） inhibitor, to obtain 17-（6-cinnamamido-hexylamino）-17-demethoxygel-danamycin （CNDG）. Its in vitro and in vivo antitumor effects were evaluated by MTT assay and xenograft in nude mice.

关键词： 17-(6-Cinnamamido-hexylamino)-17-demethoxygeldanamycin Hsp90 inhibitor

A Novel Processing Route for Ni-doped Alumina Composites

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Chinese Journal of Aeronautics 2006年第B12期19卷 55-61页

作者： JING Mao-xiang SHEN Xiang-qian ZHOU Jian-xin li dong-hong li Wang-xing School of Materials Science and Engineering Jiangsu University Zhenjiang 212013China Zhengzhou Research Institute of Chalco Henan Zhengzhou 450041 China

Alumina-based composites containing 0-15wt% Ni metallic phase were produced by hot press-sintering Ni-coated alumina powders. The Ni-coated alumina powders were prepared by the aqueous heterogeneous precipitation of alumina micro-powders and nickel sulfate salt followed by reduction process. The microstructural features and dispersion of Ni phase in Ni-coated alumina powders and the subsequent alumina-Ni cermets were investigated using scanning electron microscope （SEM）, X-ray diffractometer （XRD）, and transmission electron microscope （TEM）. The relative density of the hot press-sintered composites was measured with the Archimedes＇ method while the fracture strength and the fracture toughness were defined with the three-point bending method and the micro-indentation fracture method. In the formation of alumina-Ni cermets from sintered Ni-coated alumina powders, Ni phase to some extent limits the densification rate and stifles the coarsening and growing process of alumina grains. The Ni phase is found to be located at the interfaces and the triple-joint junctions of alumina grains which results into alteration of the fracture mode of alumina and its increased fracture strength and fracture toughness if compared with monolithic alumina.

关键词： alumina-based composite Ni-coated alumina powder heterogeneous precipitation Ni dispersion

Synthesis and Temperature-dependent Electrochemical Properties of Boron-doped Diamond Electrodes on Titanium

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Chemical Research in Chinese Universities 2012年第3期28卷 507-510页

作者： DU li-li SUN Jian-rui CUI Hang li hong-dong CUI Tian liN Hai-bo State Key Laboratory of Superhard Materials Jilin UniversityChangchun 130012P.R.China College of Chemistry Jilin UniversityChangchun 130012P.R.China State Key Laboratory of Theoretical and Computational Chemistry Institute of Theoretical ChemistryJilin UniversityChangchun 130021P.R.China

On the sand-blasting-treated titanium（Ti） substrate, the boron-doped diamond（BDD） electrodes with a wide potential window were prepared by microwave plasma chemical vapor deposition（MPCVD）. The electrochemi- cal oxidation ratios of phenol at BDD/Ti electrodes at elevated temperatures（from 20 ℃ to 80 ℃） were examined by the chemical oxygen demand（COD） of phenol electrolyte during electrolysis. The results show that the COD removal was increased at high temperatures and the optimized temperature for enhancing the electrochemical oxidation ratio of phenol is 60 ℃. The mechanism for the temperature-dependent electrochemical oxidation ratios of phenol at the electrodes was investigated. The study would be favorable for further improving the performance of BDD/Ti elec- trodes, especially working at high temperatures.

关键词： BDD/Ti electrode Microwave plasma chemical vapor deposition Phenol Electrochemical degradation

Development of remaining life prediction of crankshaft remanufacturing core

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Advances in Manufacturing 2013年第1期1卷 91-96页

作者： li-hong dong Bin-Shi Xu Nan Xue Hui-Peng Wang Hao-Yu li Science and Technology on Remanufacturing Laboratory

This paper reviewed the main research work in the field of remaining life prediction of crankshaft remanufacturing core by Science and Technology on Remanu- facturing Laboratory. Based on the results of finite element analysis, the R angle zone of crankshaft was determined as a major measuring position. A special measuring probe is developed, and bending fatigue bench tests were carried out to collect electromagnetic damage information during fatigue process. A neural network model was established to identify damage degree of crankshaft core, and a damage evaluation equipment for crankshaft core was developed.

关键词： Remanufacturing Remaining life Crankshaft Metal magnetic memory Multi-frequency eddy current

Unraveling role of double-exchange interaction in electrochemical water oxidation by external magnetic field

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Rare Metals 2024年第1期43卷 289-297页

作者： Jun li Jun-Ming li hong hong dong-Xue liu Qing-Qi Cao Dun-Hui Wang National Laboratory of Solid State Microstructures and Jiangsu Provincial Key Laboratory for Nanotechnology Nanjing UniversityNanjing 210093China School of Electronics and Information Hangzhou Dianzi UniversityHangzhou 310018China

Double-exchange(DE) interaction plays an important role in electrocatalytic oxygen evolution reaction(OER).However,precise achievement of DE interaction often requires foreign dopants or vacancy engineering,leading to destabilization of the catalysts and deterioration of *** contrast,the utilization of environmentally friendly,contactless,and continuously adjustable magnetic fields to study the OER process is profitable to avoid aforementioned interference factors and further elucidate the direct relationship_(0.5)between DE interaction and OER ***,by using cobalt hydroxide carbonate(Co(OH)(CO_(3))·xH_(2)O,CoHC) nanostructures as a proof-of-concept study,external magnetic fields are carefully implemented to verify the role of DE interaction during water oxidation *** studies reveal that external magnetic fields effectively enhance the reaction rate of the catalyst,the overpotential decreases from 386 to 355 mV(100 mA·cm^(-2)),while Tafel slopes drastically decline from 93 to 67 mV·dec^(-1)(1.0 T).Moreover,magnetic field increment exhibits robust *** in situ Raman and impedance measurements under external field,it can be found that magnetic field promotes the electron migration between Co^(2+) and Co^(3+) in the CoHC catalysts with the assistance of DE interactions,thus boosting the OER efficiency.

关键词： Magnetic field Double-exchange(DE)interaction Electrocatalysis Oxygen evolution reaction(OER) Cobalt hydroxide carbonate

EPG Comparison of Sitobion avenae (Fab.) Feeding Behavior on Three Wheat Varieties

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Agricultural Sciences in China 2008年第2期7卷 180-186页

作者： HU Xiang-shun ZHAO Hui-yan HU Zu-qing li dong-hong ZHANG Yu-hong College of Plant Protection Northwest A＆F University Yangling 712100 P.R.China

This article was to study the potential resistance mechanism of three different wheat varieties （Ww2730, Xiaoyan 22 and Batis） in the seedling stage to Sitobion avenae. The aphid feeding behavior was ascertained by stylet penetration activities monitoring using the electrical penetration graph （EPG） technique. When the aphids feed on Ww2730 seedlings, the time for the 1st duration probing was later than that on Xiaoyan 22 and Batis significantly, and the number of interrupted probing before the 1st duration probing was more than that on Xiaoyan 22 and Batis significantly, and the 1st duration probing was shorter than that on Xiaoyan 22 and Batis significantly. The durations of the stylet pierce from the extra- to the intra-cellular （pd Ⅱ-1） on Ww2730 and Xiaoyan 22 were longer than those on Batis significantly. The duration of the potential drop （pd） in C wave on Ww2730 was longer than that on Xiaoyan 22 and Batis significantly. The times and duration of the G wave （ingestion in xylem） on Ww2730 were more and longer than those on Xiaoyan 22 and Batis significantly. The times of spot G wave on Batis was more than that on Ww2730 significantly, but the duration of spot G was shorter than that on Xiaoyan 22 and Ww2730 significantly. The total time of E1 wave, the longest duration of E1 fractions, and the mean duration time of E1 fractions that followed E2 wave on Xiaoyan 22 and Batis were all significantly longer than those on Ww2730. There was no difference of the mean duration of the 1st E1 wave on the 3 varieties, but the mean durations of other E1 wave on Ww2730 and Xiaoyan 22 were shorter than those on Batis significantly. The other wave parameters, including times and durations of F and E2 were all not different on the 3 wheat varieties. It is suggested that the resistance mechanism of wheat variety Ww2730 to S. avenae is a restriction factor of feeding in epidermis, the thicker cell wall in mesophyll, and secondary metabolites or nutrition unbalance in phloem in

关键词： wheat Sitobion avenae resistance mechanism electrical penetration graph (EPG) feeding behavior

Enhanced hydrogen evolution reaction in FePt film with remanence due to decrease in domain walls

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Rare Metals 2024年第3期43卷 1108-1115页

作者： hong hong dong-Xue liu Jun li Jun-Ming li li-Qian Wu Bo Yang Qing-Qi Cao Dun-Hui Wang National Laboratory of Solid State Microstructures Collaborative Innovation Center of Advanced MicrostructuresJiangsu Provincial Key Laboratory for NanotechnologySchool of PhysicsNanjing UniversityNanjing210093China Hangzhou Dianzi University Hangzhou310018China Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Material Science and EngineeringNortheastern UniversityShenyang110819China

As an effective strategy to improve the properties of electrocatalysts,magnetic field-assisted electrocatalytic water splitting has attracted increasing attention ***,the corresponding enhancements mostly depend on the exertion of an external magnetic field during electrochemical reactions,which results in a high cost of industrial production,and makes the magnetic field manipulation of electrocatalysis become a challenging *** this work,instead of the external magnetic field,a bias magnetic field is self-supplied by the remanence state of a ferromagnetic electrocatalyst of *** to the assistance of this bias magnetic field,the FePt film in the remanence state shows the overpotential of 229 mV during hydrogen evolution reaction,which is much lower than that in its demagnetization state(283 mV).Our findings demonstrate that the remanence in ferromagnetic electrocatalysts can improve the catalytic performance,which is attributed to the decrease in domain walls.

关键词： Remanence Magnetic domains Electrocatalysis Hydrogen evolution reaction(HER)