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Exfoliation corrosion of extruded Mg-Li-Ca alloy

Journal of Materials Science & Technology 2018年第9期34卷 1550-1557页

作者： Zi-You Ding Lan-Yue Cui Rong-Chang Zeng Yan-Bin Zhao Shao-kang Guan Dao-kui Xu Cun-Guo Lin College of Materials Science and Engineering Shandong University of Science and Technology Qingdao 266590 China School of Materials Science and Engineering Zhengzhou University Zhengzhou 450002 China CAS Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Science and Technology on Marine Corrosion and Protection Laboratory Qingdao 266071 China Qingdao Branch of Luoyang Ship Material Research Institute Qingdao 266101 China

Exfoliation on as-extruded Mg-1 Li-1 Ca magnesium alloy was investigated after an immersion in 3.5 wt%NaCl aqueous solution for 90, 120 and 150 days through optical microscope, digital camera, scanning electron microscope, electrochemical workstation, scanning Kalvin probe, X-ray diffraction and Fourier transform infrared spectroscope. The results demonstrated that exfoliation corrosion occurred on extruded Mg-1 Li-1 Ca alloy due to elongated microstructure parallel to surface, and delamination of lamellar structure resulted from galvanic effect and wedge effect. Skin layer with fine grains exhibited better corrosion resistance, whereas the interior with coarse grains and the intermetallic compound,Mg2 Ca particles existing in a fibrous structure, dispersed along grain boundaries and extrusion direction in a line. Furthermore, galvanic effect between Mg2 Ca particles and their neighboring a-Mg matrix facilitated dissolution of Mg2 Ca particles and a-Mg matrix; wedge effect was caused by formation of corrosion products. Exfoliation corrosion of extruded Mg-Li-Ca alloys might be a synergic effect of pitting corrosion,filiform corrosion, intergranular corrosion and stress corrosion. Finally, exfoliation corrosion mechanism was proposed.

关键词： Magnesium-lithium alloy Exfoliation corrosion Intermetallic compound Extrusion Microstructure

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Characteristics of air quality in Tianjin during the Spring Festival period of 2015

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Atmospheric and Oceanic Science Letters 2016年第1期9卷 15-21页

作者： TANG Miao Jl Dong-Sheng GAO Wen-kang YU Zhong-Wang CHEN kui CAO Wan Tianjin Environment Monitoring Center Tianjin 300191China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100083China University of Chinese Academy of Sciences Beijing 100049China Tianjin Environmental Protection Bureau Tianjin 300191China

To better understand the characteristics of air quality and the relationship between the chemical composition evolution and source variation,an intensive atmospheric campaign was conducted in Tianjin,a megacity of the North China Plain,from 10 February to 6 March *** were 20 days exceeding the threshold value of secondary Chinese Ambient Air Quality Standards for PM2.5(75 μg m-3,daily average over 24 h)during the study *** air pollution episodes were selected for *** the pre-holiday pollution episode,NH^+_4,NO^-_3,and SO^(2-)_4 were more abundant,indicating that air pollution was caused by motor vehicle exhaust emissions and coal consumption under unfavorable meteorological *** Chinese Lunar New Year's Eve,widespread use of fireworks resulted in extremely high aerosol *** displays caused increases in K+ and also enrichment of SO^(2-)_4 relative to NO^-_*** holiday pollution episode was caused by regional transport,characterized by abundant SO^(2-)_4 and NH^+_*** addition,the aging processes of the particles from fireworks discharge played an important role in the formation of NO-3and SO^(2-)_*** Lantern Festival episode was characterized by a transition from the enrichment of K+ to secondary inorganic ions(NO^-_3,SO^(2-)_4,and NH^+_4).The results of this study are useful for a detailed understanding of the variation in atmospheric compositions and sources caused by anthropogenic activity,and highlight the importance of controlling intensive fireworks discharge.

关键词： tianjin water-soluble ions fireworks organic carbon elemental carbon

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Effects of light intensity and photoperiod on the growth and stress response of juvenile Nile tilapia(Oreochromis niloticus)in a recirculating aquaculture system

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Aquaculture and Fisheries 2023年第1期8卷 85-90页

作者： kui Wang kang Li Liping Liu Cristina Tanase Rainier Mols Michiel van der Meer National Demonstration Center for Experimental Fisheries Science Education Shanghai Ocean UniversityShanghai201306China Shanghai Engineering Research Center of Aquaculture Shanghai201306China International Research Center for Marine Biosciences at Shanghai Ocean University Ministry of Science and TechnologyShanghai201306China Philips Lighting Aquaculture AE Eindhoven5656the Netherlands

Light is an essential natural factor of fish growth and development.A light regime in indoor aquaculture is critical for sustainable fish *** research aimed to investigate the effect of light intensity and photoperiod on the growth performance and stress response of Nile tilapia(Oreochromis niloticus),which is an important commercial species,in a recirculating aquaculture system(RAS).Fingerlings with an average weight of 5±0.9 g were randomly assigned to nine 1.5 m3 tanks with 145 fish in each tank,cultured under different light intensities(1000,2000,and 3000 lx)and photoperiods(12L:12D,18L:6D,24L:0D),and fed to apparent satiation twice a day for 160 *** growth of tilapia subjected to 2000 lx was significantly better than that exposed to 1000 and 3000 lx(P0.05).Light intensity and photoperiod manipulation did not cause a significant chronic stress response in *** study demonstrated that light intensity,especially at 2000 lx,and photoperiod manipulation could stimulate the growth of tilapia in the RAS and significantly affect economic *** study also served as an important reference for tilapia indoor aquaculture.

关键词： Recirculating aquaculture system Tilapia Light intensity Photoperiod Growth Stress response

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Hybrid optimization model and its application in prediction of gas emission

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Journal of Coal Science & Engineering(China) 2012年第3期18卷 280-284页

作者： FU Hua SHU Dan-dan kang Hai-chao YANG Yi-kui Faculty of Electrical and Engineering Control Liaoning Technology UniversityHuludao 125105China

According to the complex nonlinear relationship between gas emission and its effect factors, and the shortcomings that basic colony algorithm is slow, prone to early maturity and stagnation during the search, we introduced a hybrid optimization strategy into a max-rain ant colony algorithm, then use this improved ant colony algorithm to estimate the scope of RBF network parameters. According to the amount of pheromone of discrete points, the authors obtained from the interval of net- work parameters, ants optimize network parameters. Finally, local spatial expansion is introduced to get further optimization of the network. Therefore, we obtain a better time efficiency and solution efficiency optimization model called hybrid improved max-min ant system （H1-MMAS）. Simulation experiments, using these theory to predict the gas emission from the working face, show that the proposed method have high prediction feasibility and it is an effective method to predict gas emission.

关键词： max-rain ant colony algorithm optimization model gas emission prediction

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赤水河流域蛾类昆虫种类及区系组成

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生物灾害科学 2020年第3期43卷 265-269页

作者：王丽娜陈模芳钱正敏唐艳龙康奎班帮胜遵义师范学院生物与农业科技学院/贵州省赤水河流域动物资源保护与应用研究重点实验室贵州遵义563002

【目的】为了解赤水河流域主要蛾类昆虫种类及区系组成。【方法】采用定点灯诱法对赤水河流域的蛾类昆虫进行调查,分类鉴定后分析蛾类昆虫的种类及区系组成。【结果】考查共采集蛾类昆虫2000余号,鉴定出蛾类昆虫共有24科、168属、217种... 详细信息

【目的】为了解赤水河流域主要蛾类昆虫种类及区系组成。【方法】采用定点灯诱法对赤水河流域的蛾类昆虫进行调查,分类鉴定后分析蛾类昆虫的种类及区系组成。【结果】考查共采集蛾类昆虫2000余号,鉴定出蛾类昆虫共有24科、168属、217种;其中以夜蛾科、尺蛾科、天蛾科、灯蛾科和螟蛾科为优势科,从属的数量看,上述5个科占总属数的68.46%,从种的数量来看,夜蛾科最多,有40种,占总种数的18.43%,其次是灯蛾科,有30种,占总种数的13.82%。蛾类昆虫区系分布中,由多到少依次为:西南区、华南区、华中区、华北区、东北区、蒙新区和青藏区,其总比例依次为2400.00%、1194.79%、1192.23%、693.96%、603.01%、291.14%和229.32%。【意义】研究为赤水河流域蛾类昆虫多样性的保护和开发利用提供科学依据。

关键词：赤水河流域蛾类昆虫种类区系组成

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Progress and perspective of the cathode/electrolyte interface construction in all-solid-state lithium batteries

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Carbon Energy 2021年第6期3卷 866-894页

作者： Shiming Su Jiabin Ma Liang Zhao kui Lin Qidong Li Shasha Lv Feiyu kang Yan-Bing He Shenzhen Geim Graphene Center International Graduate School at ShenzhenTsinghua UniversityShenzhenChina Laboratory of Advanced Materials School of Materials Science and EngineeringTsinghua UniversityBeijingChina Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijingChina

Security risks of flammability and explosion represent major problems with the use of conventional lithium rechargeable batteries using a liquid *** application of solid-state electrolytes could effectively help to avoid these safety ***,integrating the solid-state electrolytes into the all-solid-state lithium batteries is still a huge challenge mainly due to the high interfacial resistance present in the entire battery,especially at the interface between the cathode and the solid-state electrolyte pellet and the interfaces inside the ***,recent progress made from investigations of cathode/solid-state electrolyte interfacial behaviors including the contact problem,the interlayer diffusion issue,the space-charge layer effect,and electrochemical compatibility is presented according to the classification of oxide-,sulfide-,and polymer-based solid-state *** also propose strategies for the construction of ideal next-generation cathode/solid-state electrolyte interfaces with high room-temperature ionic conductivity,stable interfacial contact during long cycling,free formation of the space-charge region,and good compatibility with high-voltage cathodes.

关键词： cathode configuration design interface lithium battery solid-state electrolyte

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Microstructure evolution and mechanical properties of PESR 55Cr17Mo1VN plastic die steel during quenching and tempering treatment

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Journal of Iron and Steel Research International 2021年第12期28卷 1625-1633页

作者： Cong-peng kang Fu-bin Liu Huai-bei Zheng Hua-bing Li Zhou-hua Jiang kui Chen Hao-yang Suo Xin-hao Yu School of Metallurgy Northeastern UniversityShenyang110819LiaoningChina State Key Laboratory of Metal Material for Marine Equipment and Application Anshan114002LiaoningChina

55Cr17Mo1VN high nitrogen martensitic stainless steel is usually applied to the high-quality mold,which is largely produced by the pressurized electro slag remelting *** microstructure evolution of quenching and tempering heat treatment were investigated and an optimal heat treatment process to achieve excellent mechanical properties was found *** main precipitates in the steel included carbon-rich type M_(23)C_(6) and nitrogen-rich type M_(2)*** increasing austenitizing temperature,the equivalent diameter of the precipitates got fined,and retained austenite content increased significantly when the austenitizing temperature exceeded 1020℃.The fracture mode gradually changed from brittle fracture to ductile fracture with increasing tempering temperature from 200 to 550℃.The experimental steel tempered at 350℃ achieved a good combination of hardness(60.6 HRC)and strength(2299.2 MPa)to meet service *** M_(23)C_(6) precipitated along martensite lath boundaries and the secondary hardening phenomenon occurred when the tempering temperature was 450℃.Due to the high nitrogen content,M_(2)N precipitated from the inside of laths and matrix when tempered at 550℃.

关键词： Microstructure Mechanical property Plastic die steel Quenching Tempering Precipitate

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Synthesis, Crystal Structure and Herbicide Activity of Three Phenyl-naphthyl Methanone Derivatives

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Chinese Journal of Structural Chemistry 2019年第11期38卷 1881-1888页

作者： FU Ying ZHANG Shuai-Qi HAN Zhi-Bo WANG kui kang Jing-Xin YE Fei College of Science Northeast Agricultural UniversityHarbin 150030China Daqing Chemical Research Center of Petrochemical Research Institute China PetroleumDaqing 163714China

Three phenyl-naphthyl methanone derivatives have been designed and synthesized through alkylation and Friedel-Crafts acylation *** the compounds were characterized by IR,1H NMR,13C NMR and H *** single crystal structure of the compounds has been further determined by X-ray diffraction.(4-Ethoxynaphthalen-1-yl)(2-methylphenyl)methanone(3a)crystallizes in monoclinic system,P21/c space group with a=13.144(3),b=11.041(2),c=11.320(2)?,β=106.65(3)°,V=1573.7(5)?3,Dc=1.225 Mg/m3,Z=4,F(000)=616,μ(MoKα)=0.078 mm-1,R=0.0928 and wR=0.1556.(4-Ethoxynaphthalen-1-yl)(2-hydroxyphenyl)methanone(3b)belongs to the monoclinic system,P21/c space group with a=9.985(2),b=10.814(2),c=14.353(3)?,β=105.49(3)°,V=1493.6(5)?3,Dc=1.300 Mg/m3,Z=4,F(000)=616,μ(MoKα)=0.087 mm-1,R=0.0568 and wR=0.1262.(4-Methoxynaphthalen-1-yl)(4-methylphenyl)methanone(3c)crystallizes in monoclinic system,P21/c space group with a=7.6130(15),b=15.068(3),c=12.880(3)?,β=100.63(3)°,V=1452.1(5)?3,Dc=1.264 Mg/m3,Z=4,F(000)=584,μ(MoKα)=0.081 mm-1,R=0.0804 and wR=*** presence of van der Waals forces leads to the stability of the ***,compounds 3a^c showed herbicidal activity against the monocotyledon plant barnyard grass(Echinochloa crus-galli).At the concentration of 0.75 mmol/m^2,compound 3b(Ct=0.436±0.116 mg/g)exhibited better activity than pyrazoxyfen(Ct=0.537±0.073 mg/g).

关键词： phenyl-naphthyl methanone synthesis single crystal structure bioactivity

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Effect of slag composition on elements oxidation behavior of GH984G superalloy for electroslag remelting withdrawal process

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Journal of Iron and Steel Research International 2022年第5期29卷 761-771页

作者： Fu-bin Liu Jun-zhe Gao Hai-bo Cao Hua-bing Li Zhou-hua Jiang Xin Geng Cong-peng kang kui Chen Rui-dong An School of Metallurgy Northeastern UniversityShenyang110819LiaoningChina State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang110819LiaoningChina Hefei Institutes of Physical Science Chinese Academy of SciencesHefei230031AnhuiChina

The composition of a slag system has been shown to be particularly important and influential for the new technology of electroslag remelting withdrawal *** oxidation of the GH984G alloy elements,in contact with different contents of CaF_(2)–CaO–Al_(2)O_(3)–MgO–TiO_(2)–SiO_(2)in various slag systems,has been investigated in the present study by performing slag–metal equilibrium experiments and ion and molecule coexistence theory *** results show that CaF_(2)and MgO have only a minor effect on the oxidation rates of Al and Ti in the GH984G ***,it was found that SiO_(2)would intensify the oxidation degree of Al and Ti,and Al was found to become easier oxidized than ***,CaO was found to reduce the activity of SiO_(2)and,thereby,also the oxidation degree of Al and ***,TiO_(2)was found to reduce the oxidation rate of Ti and instead increase the oxidation rate of ***,the effect of Al_(2)O_(3)on the oxidation of Al and Ti was observed to be opposite to that of TiO_(2).The calculated results were found to be in good agreement with experimental ***,viscosity experiments showed that CaO would rapidly increase the viscosity of the slag at low temperatures,and that the viscosity of the slag would increase with an increase in SiO_(2)content.

关键词： Electroslag remelting withdrawal Slag GH984G superalloy Oxidation rate Viscosity

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Orange-red, green, and blue fiuorescence carbon dots for white light emitting diodes

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Journal of Materials Science & Technology 2020年第15期47卷 184-191页

作者： Ling Jin Li Zhang Lei Yang Xingrong Wu Cheng Zhang kang Wei Lifang He Xinya Han Hongbin Qiao Abdullah MAsiri Khalid AAlamry kui Zhang School of Chemistry and Chemical Engineering Anhui University of TechnologyMa'anshan243032China Department of Chemistry University of North Carolina at Chapel HillChapel HillNC27599USA Key Laboratory of Metallurgical Emission Reduction&Resources Recycling Ministry of Education(Anhui University of Technology)Ma'anshan243002China Chemistry Department Faculty of ScienceKing Abdulaziz UniversityJeddah21589Saudi Arabia

Fluorescent carbon dots(CDs) are admirable nanomaterials due to their superior optical properties and low ***,regulation of the emission colors in CDs for lighting device still remains a *** this work,we developed a green hydrothermal method to obtain three emission colors of CDs using L-tyrosine(for blue CDs),o-phenylendiamine(for green CDs) and L-tyrosine/o-phenylendiamine mixture(for orange-red CDs).These CDs possess good water dispersibility,strong emission with high quantum yields,and excellent ***,the resulting CDs were dispersed in polyvinyl alcohol(PVA) matrix to yield solid state films,where the self-quenching effect in solid state was effectively avoided.A full-color light-emitting diode was fabricated by packing the CDs-PVA composites on the top of a UV-chip,which have superior potential applications in CDs-based solid-state lighting system.

关键词： Fluorescence Photoluminescene Carbon dots Self-quenching effect Light-emitting diode

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