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Chinese Journal of Chemical Engineering 2018年第4期26卷 753-760页

作者： Junlei Zhang Zhen ma Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP^3) Department of Environmental Science and Engineering Fudan University Shanghai 200433 China Shanghai institute of Pollution Control and Ecological Security Shanghai 200092 PR China

Porous g-C3n4samples were obtained by simply calcining bulk g-C3n4in static air in a muffle *** photocatalytic performance of these samples was evaluated through the removal of aqueous organic dyes（methylene blue and methyl orange）and tetracycline hydrochloride under visible-light irradiation（λ〉420 nm）.Compared to bulk g-C3n4,porous g-C3n4exhibited much better capability for removing these contaminants,especially under visible-light irradiation,due to the enlarged specific surface area and more efficient separation of photogenerated charge *** particular,porous g-C3n4obtained by calcining bulk g-C3n4in air at 525℃ showed the highest visible-light-driven catalytic activity among these *** radical anions（·O2^-）were found to be the primary active species responsible for photodegradation.

关键词： C3n4 Catalyst Reaction Waste treatment Dyes Tetracycline hydrochloride

Water mass characteristics in the western north Pacific based on a streamfunction projection

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Science China Earth Sciences 2015年第11期58卷 2067-2077页

作者： ma Xiao SUn Che institute of Oceanology Chinese Academy of Sciences College of Earth Sciences University of Chinese Academy of Sciences

A streamfunction projection method called gravest empirical mode(GEM) is applied to the hydrographic section at 137°E to filter out eddy noises in the western north Pacific and derive quantitative ensemble-average water mass properties in the north Equatorial Current region. The GEM fields capture more than 80% of total property variances in the thermocline layer. The core layer structures of key water masses, including the north Pacific Tropical Water(nPTW) and the north Pacific intermediate Water(nPiW), are examined with a definition of water mass boundary based on property gradient. it shows that a tongue of maximal root-mean-square(RMS) residual exists in the upper half of nPiW for all water properties. These subsurface RMS tongues appear to be close to sharp property gradients. it is the first time a GEM diagnosis is applied to nutrient data, which reveals a drastic difference of n/P reaction rate ratio above and below the maximal-nutrient core at 1250 m. Additionally, a GEM velocity reconstruction successfully produces the north Equatorial Undercurrent(nEUC), demonstrating the stable thermal-wind nature of this newly-discovered current.

关键词： streamfunction projection gravest empirical mode water masses western north Pacific

High-Speed Friction Stir Welding of T6-Treated B4Cp/6061Al Composite

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Acta Metallurgica Sinica(English Letters) 2020年第1期33卷 67-74页

作者： Y.Z.Li Y.n.Zan Q.Z.Wang B.L.Xiao Z.Y.ma Key Laboratory of nuclear materials and Safety Assessment Institute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China Shenyang national Laboratory for materials Science Institute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China University of Science and Technology of China Shenyang 110016China

T6-treated 20 wt% B4 Cp/6061 Al sheets were joined under welding speeds of 400–1200 mm/min by friction stir welding(FSW) with a threaded cermet pin. The macro-defect-free FSW joints could be achieved at high welding speeds up to 1200 mm/min, but larger plunge depth was required at the welding speeds of 800 and 1200 mm/min to eliminate the tunnel defect. in the nugget zone(nZ) of the joints, the B4 C particles were broken up and uniformly redistributed. The nZ exhibited lower hardness than the base metal(BM), and the hardness value almost did not change with increasing welding speed, attributable to the dissolution of precipitates. Compared with the BM, the joints showed lower tensile strength. As the welding speed increased from 400 to 800 mm/min, the joint efficiencies were nearly the same and up to ~ 73%. When the welding speed increased up to 1200 mm/min, the tensile strength significantly decreased, due to the occurrence of kissing bond defect at the bottom of the nZ. With increasing welding speed, the fracture location of the joints transferred gradually from the heat-affected zone to the nZ due to the kissing bond defects.

关键词： Metal-matrix composites Microstructures Mechanical properties Friction stir welding High-speed welding

Rh_2O_3/monoclinic CePO_4 composite catalysts for n_2O decomposition and CO oxidation

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Chinese Journal of Chemical Engineering 2018年第1期26卷 109-115页

作者： Huan Liu Zhen ma Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention Department of Environmental Science and EngineeringFudan University

CePO4 （in particular, monoclinic CePO4） has been rarely used to make supported catalysts. Herein, monoclinic CeP04 nanoparticles were prepared by calcining hexagonal CePO4 nanomds （prepared by precipitation） in air at 900 ℃. Monoclinic CePO4 nanowires were prepared by calcining hexagonal CePO4 nanowires （prepared by hydrothermal synthesis at 150 ℃） in air at 900 ℃. Both monoclinic CePO4 materials were used to support Rh2O3 by impregnation using Rh（nO3）3 as a precursor （followed by calcination）. The catalytic performance of Rh2O3/monoclinic CePO4 composite materials in n2O decomposition and CO oxidation was investigated. it was found that Rh2O3 supported on monoclinic CePO4 nanowims was much more active than Rh2O3 supported on monoclinic CePO4 nanoparticles. The stability of catalysts as a function of reaction time on stream was studied in both reactions. The influence of co-fed CO2, O2, and H2O on the catalytic activity in n20 decomposition was also studied. These catalysts were characterized by employing n2 adsorption-desorption, iCP-OES, XRD, TEM, XPS, H2-TPR, O2-TPD, and CO2-TPD. The correlation between physicochemical properties and catalytic properties was discussed.

关键词： Rh2O3 CePO4 n2O decomposition CO oxidation Catalyst

The Amperometric Glucose Enzyme Electrode by immobilized Glucose Oxidase in Glucose Oxidase/n-ethyl-Poly (4-vinyl)pyridine Multilayer

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Chinese Chemical Letters 1998年第11期9卷 0-0,0页

作者： ma, YZ Heze Teachers Coll Dept Chem Shandong 274015 Peoples R China

Multilayers of glucose oxidase(GOD)/n-ethyl-poly (4-vinyl) pyridine (EPVP) have been assembled on thiol self-assembled monolayers on gold *** electrode can be used as an amperometric enzyme elcctrode for glucose. Fe (Cn)63-/4- incorporated in EPVP layer acts as the electron mediator, the linear range was 0.1 to 6 mmol/L when the number of GOD layers was 5.

关键词： Enzyme electrode glucose oxidase n-ethyl-poly (4-vinyl) pyridine. multilayer.

Deposition of Ti-Si-n coatings in deep blind-hole with pulsed dc power

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 260-263页

作者： ma Da-yan ma Sheng-li XU Ke-wei State Key Laboratory for Mechanical Behavior of materials Xi''an Jiaotong University Xi''an 710049 China State Key Laboratory for Mechanical Behavior of MaterialsXi''an Jiaotong University Xi''an 710049 China State Key Laboratory for Mechanical Behavior of MaterialsXi''an Jiaotong University Xi''an 710049 China

Multiphase nanocomposite Ti-Si-n coatings deposited by pulsed dc plasma enhanced chemical vapor deposition technique on the surface of HSS substrate, which were bolted with deep blind-hole to simulate the complexshaped surface of various tools, were investigated. The micrographs show that the surface morphologies of the coatings become coarser with an increasing depth of the bottom holes. And the silicon content increases in Ti-Si-n coatings, which are composed of nanocrystalline Tin, nano-sized amorphous Si3n4, and occasionally amorphous or nanocrysralline TiSi2. The thickness of the coatings decreases with the increasing depth of holes, which may result from the changes of the composition in the coatings. The microhardness of the coatings increases firstly with the increasing depth of holes, reaches a maximum value of about HV5 700 at 10mm depth, and then decreases at larger depth.

关键词： nanocomposite pulsed dc PCVD Ti-Si-n deep blind-hole

Enhancing capacitive deionization performance and cyclic stability of nitrogen-doped activated carbon by the electro-oxidation of anode materials

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Chinese Journal of Chemical Engineering 2024年第5期69卷 23-33页

作者： Xiaona Liu Baohua Zhao Yanyun Hu Luyue Huang Jingxiang ma Shuqiao Xu Zhonglin Xia Xiaoying ma Shuangchen ma School of Environmental Science and Engineering North China Electric Power UniversityBaoding 071003China Huadian Zhengzhou machinery Design and Research institute Co. LtdZhengzhou 450002China Huadian inner Mongolia Energy Co. Ltd.Baotou Power Generation BranchBaotou 014013China

Electrode materials with high desalination capacity and long-term cyclic stability are the focus of capacitive deionization(CDi) community. Understanding the causes of performance decay in traditional carbons is crucial to design a high-performance material. Based on this, here, nitrogen-doped activated carbon(nAC) was prepared by pyrolyzing the blend of activated carbon powder(ACP) and melamine for the positive electrode of asymmetric CDi. By comparing the indicators changes such as conductivity, salt adsorption capacity, pH, and charge efficiency of the symmetrical ACP-ACP device to the asymmetric ACP-nAC device under different CDi cycles, as well as the changes of the electrochemical properties of anode and cathode materials after long-term operation, the reasons for the decline of the stability of the CDi performance were revealed. it was found that the carboxyl functional groups generated by the electro-oxidation of anode carbon materials make the anode zero-charge potential(E_(pzc)) shift positively,which results in the uneven distribution of potential windows of CDi units and affects the adsorption capacity. Furthermore, by understanding the electron density on C atoms surrounding the n atoms, we attribute the increased cyclic stability to the enhanced negativity of the charge of carbon atoms adjacent to quaternary-n and pyridinic-oxide-n.

关键词： Anodic oxidation Capacitive deionization Cyclic stability n-doping

Taxonomic status of grey-headed Yellow Wagtails breeding in western China

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Avian Research 2021年第4期12卷 534-543页

作者： Alexander Hellquist Fredrik Friberg Petter Haldén Peter Schmidt Ming ma Gou Jun Urban Olsson Per Alström Fatburs kvarngata 17 11864 StockholmSweden Xinjiang institute of Ecology and Geography Chinese Academy of SciencesNo.818 Beijing RoadUrumqi 830011XinjiangChina Xinjiang Birdwatching Society 311 Nongda East RoadUrumqi 830091XinjiangChina Systematics and Bio-diversity Department of Biology and Environmental SciencesUniversity of GothenburgGöteborgSweden Gothenburg Global Biodiversity Centre GothenburgSweden Animal Ecology Department of Ecology and GeneticsEvolutionary Biology CentreUppsala UniversityNorbyvägen 18D75236 UppsalaSweden Key Laboratory of Zoological Systematics and Evolution Institute of ZoologyChinese Academy of SciencesBeijing 100101China Edeby 9 74191 KnivstaSweden Lenabergsvägen 33 74392 VattholmaSweden Tallmovägen 9 75645 UppsalaSweden

Background:Field studies from 2011 onwards have demonstrated the presence of a breeding population of Yellow Wagtails(Motacilla flava)in the Xinjiang Uygur Autonomous Region,China that is phenotypically distinct from known subspecies occurring in *** we describe the plumages and vocalisations of this population and discuss its taxonomic ***:The analysis of plumage is based on field studies and photos available *** of vocalisations are compared with recordings from other Yellow Wagtail populations,and differences are analysed based on *** DnA from one individual is compared to other Yellow Wagtail ***:Unlike *** subspecies breeding in or near Xinjiang,males in the studied population show a blue-grey head without prominent white supercilium,being most similar to the widely disjunct *** differ from the similarly widely allopatric ***,which might occur as a migrant or vagrant in Xinjiang,by on average cleaner yellow breast and more extensive white on the throat,and from the widely disjunct *** and ***,which might also occur on migration in that area,by softer contact calls and slower pace of *** are similar to female *** in *** mitochondrial nD2 tree shows the single sample from Xinjiang to be nested in the clade of western Yellow Wagtail ***:We discuss whether the Xinjiang breeding population could represent an intergrade between subspecies breeding nearby,or whether it is better regarded as a separate as yet unrecognized *** argue that the localization of its apparent range in relation to other subspecies along with fairly consistent male and female plumages suggest that it is more likely to represent an undescribed taxon,but conclude that more research is needed to firmly establish its status.

关键词： Bioacoustics Mitochondrial DnA Morphology Motacilla flava Systematics Undescribed populations

Effects of progressive drought on photosynthesis and partitioning of absorbed light in apple trees

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Journal of integrative Agriculture 2015年第4期14卷 681-690页

作者： ma Ping BAi Tuan-hui ma Feng-wang College of Horticulture Northwest A&F University/State Key Laboratory of Crop Stress Biology for Arid Areas

To understand how drought stress affects CO2 assimilation and energy partitioning in apple（malus domestica Borkh.）, we investigated photosynthesis and photo-protective mechanisms when irrigation was withheld from potted Fuji trees. As the drought progressing, soil relative water content（SRWC） decreased from 87 to 24% in 15 d; this combined the decreasing in leaf relative water content（LRWC）, net photosynthesis rate（P n） and stomatal conductance（G s）. However, the concentrations of chlorophylls（Chl） remained unchanged while P n values were declining. Photochemistry reactions were slightly down-regulated only under severe drought. Rubisco activity was significantly decreased as drought conditions became more severe. The actual efficiency of photosystem ii（ΦPSii） was diminished as drought became more intense. Consequently, xanthophyll-regulated dissipation of thermal energy was greatly enhanced. Simultaneously, the ratio of ΦPSii to the quantum yield of carbon metabolism, which is measured under non-photorespiratory conditions, increased in parallel with drought severity. Our results indicate that, under progressive drought stress, the reduction in photosynthesis in apple leaves can be attributed primarily to stomatal limitations and the inhibited capacity for CO2 fixation. Xanthophyll cycle-dependent thermal dissipation and the Mehler reaction are the most important pathways for dispersing excess energy from apple leaves during periods of drought stress.

关键词： apple drought stress energy dissipation photosynthesis

Rubbing-induced Vibration Response Analysis of Dual-Rotor-Casing System

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Transactions of nanjing University of Aeronautics and Astronautics 2018年第1期35卷 101-108页

作者： ma Xinxing ma Hui Zeng Jin Piao Yuhua School of Mechanical Engineering and Automation Northeastern University State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University

Considering gyroscopic effects caused by rotational speed,torsional vibration as well as coupling effects among inner rotor,out rotor and casing,a dynamic model of the dual-rotor-casing system is established using finite element(FE)*** comparing the natural characteristics obtained from maTLAB and AnSYS,the developed model is *** rubbing-induced vibration responses in dual-rotor-casing system are *** effects of rotational speed and speed ratio on rubbing vibration responses of the system are *** show that different combined frequency components will appear in the spectrum except two unbalanced excitation frequencies and their multiple frequency components,and these frequencies can be used as the dual-rotor aero-engine rubbing failure diagnosis frequencies when rubbing ***,the amplitude of torsional vibration is larger than that of lateral vibration under the same working condition,and speed ratio has a great impact on the periodicity of the system rubbing-induced motion *** amplitude of rubbing-induced responses under counter-rotation is less than that under co-rotation with the same parameters.

关键词： dual-rotor-casing system rubbing fault finite element method coupling dynamic