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Acta Metallurgica Sinica(English Letters) 2017年第12期30卷 1192-1200页

作者： Wei-Min gui Hong-Yu Zhang Min Yang Tao Jin Xiao-Feng Sun qi Zheng Superalloys Division Institute of Metal ResearchChinese Academy of Sciences School of Materials Science and Engineering University of Science and Technology of China State Key Laboratory of Solidification Processing Northwestern Polytechnical University

The intrinsic relationship between the microstructure evolution and thermal fatigue behavior of a single-crystal cobalt-base superalloy has been investigated. The thermal fatigue tests are performed cyclically between room temperature and 1050 ℃ using V-notch plate specimens. Three states of thermal fatigue specimens are selected： the as-cast, solutionized as well as aged states. The solution treatment is carried out at 1260 ℃ for 24 h, which results in the dissolution of most of interdendritic continuous primary carbides. The subsequent aging treatment is carried out at 1100 ℃ for 100 h after solution treatment, resulting in the precipitation of a profusion of chain- and point-like M23C6 carbides in the matrix. The results indicate that the heat treatment can improve the thermal fatigue properties of the alloy and the effect of the solution treatment is more prominent than that of the aging treatment. The coarse and continuously distributed primary carbides in the as-cast state are changed into small and discontinuous distribution by heat treatment, which is the dominant factor in the improvement of thermal fatigue property. Additionally, the effect of oxidation behavior during thermal fatigue test on the thermal fatigue behavior is also studied.

关键词： Cobalt-base superalloys Heat treatment Thermal fatigue Carbide Oxidation

Structural Changes in Nitrogen-Doped a C:H Films

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Chinese Physics Letters 1996年第7期13卷 537-540页

作者： LIU Yi-chun KONG Xiang-gui YU Ji-qi FAN Xi-wu Tagliaferro Alberto Institute of Theoretical Physics Northeast Normal UniversityChangchun 130024 Changchun Institute of Physics Chinese Academy of SciencesChangchun 130021 Changchun Institute of Physics Chinese Academy of Sciences Changchun 130021 Dipartimento di Fisica Politecnico di TorinoCroso Duca degli Abruzzi 2410129 TorinoItalia

The influence of nitrogen on the microstructure of a-C:H film is investigated by infrared,photoluminescence(PL),and transmittance-reflectance *** is indicated that nitrogen incorporation into a-C:H network will weaken some C-H bonds,which is confirmed by differential scanning calorimeter experimental *** is also demonstrated that nitrogen entering into a-C:H film can raise luminescence *** the other hand,nitrogenation will reduce PL thermal stability.

关键词： stability spectra film

Study on Removing Zinc from Nickel Electrolyte by Ion-exchange

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Journal of Central South University 2000年第4期12卷 194-197页

作者： ZHANG gui-qing ZHANG qi-xiu XIAO Lian-sheng GONG Bo-fan Metallurgical Separation Science and Engineering Lab. Central South UniversityChangsha 410083China

In the process of nickel production by diaphragm electrolysis, the quality of the product has been tremendously affected by the content of zinc in the nickel electrolyte. Removing zinc from nickel electrolyte by ion-exchange is studied in the paper. Resin D201 is selected as the resin for zinc removing. Effects of the operative parameters, such as temperature, pH value and the contact time on zinc adsorption are observed and the desorption feature of the zinc-loaded resin is inspected. The results show that macroporous anion-exchange resin D201 has excellent adsorption and desorption properties. Its breakthrough capacity and saturation capacity in zinc adsorption reach 0.81 g/L of zinc and 1.16 g/L of zinc respectively, when the operative temperature is 60 °C and the contact time is only 5 min. In addition, compared with gel type IER 201 × 7 used industrially nowadays, this resin has better wearability and greater intensity.

关键词： zinc removal nickel electrolyte ion-exchange

Electric transport properties and temperature stability of magnetoresistance of composite system between La_(8/9)Sr_(1/45)Na_(4/45)MnO_3 and Sb_2O_3

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Rare Metals 2013年第4期32卷 363-368页

作者： gui-Ying Wang Yong-Gang Tang qi-Xiang Song Ming-Yu Zhang Zhen-Sheng Peng Anhui Key Laboratory of Spintronic and Nano-materials Research School of Mechanical and Electronic Engineering Suzhou University

The samples ofLa8/9Sr1/45Na4/45MnO3 （LSNMO）/x/2（Sb2O3） were prepared by the solid-state reaction method. The electric transport properties and the temperature stabil-ity of magnetoresistance （MR） of the samples were studied through the measurements of X-ray diffraction patterns, resistivity-temperature （ρ-T） curves, mass magnetization-temperature （σ-T） curves, and magnetoresistance-temper-ature （MR-T） curves. The results indicate that the p-Tcurves of the original material LSNMO show two peaks, and the phenomenon of two peaks of ρ-T curves disappears for the composite samples, which can be explained by a competition between surface-phase resistivity induced by boundary-dependent scattering and body-phase resistivity induced by paramagnetism-ferromagnetism transition. For all the sam-ples in the low temperature range, MR increases continu-ously with the decrease of temperature, which shows a characteristic of low-field magnetoresistance. However, MR basically keeps the same in the high temperature range. The paramagnetism-ferromagnetism transition is observed in the high temperature range due to a composite between perov-skite manganite and insulator, which can enhance the tem-perature of MR appearance in the high temperature range and make it to appear near room temperature. For the sample with x = 0.12, MR remains constant at the value of 7.5 % in the temperature range of 300-260 K, which achieves a tem-perature stability of MR near room temperature. In addition,for the sample with x = 0.16, MR is above 6.8 % in the high temperature range of 318-252 K （△T = 66 K）. MR almost remains constant in this temperature range, which favors the practical application of MR.

关键词： Electric transport property Temperaturestability of magnetoresistance Two-phase composite Perovskite manganite

Gridded inventories of historical usage for selected organochlorine pesticides in Heilongjiang River Basin, China

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Journal of Environmental Sciences 2006年第4期18卷 822-826页

作者： LIU Li-yan JIANG An-xi REN Nan-qi JIANG gui-bin LI Yi-fan School of Municipal and Environmental Engineering ＇Harbin Institute of Technology Harhin 150090 China Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Atmospheric Environment Service Environment Canada Downsview Ontario Canada

The use of technical HCH （1, 2, 3, 4, 5, 6-hexachlorocyclohexane）, DDT （dichlorodiphenyltrichloroethane） and lindane in Heilongjiang River Basin （HRB） of China was studied. Between 1952 and 1984 the total usage in the HRB was 108900 t for technical HCH, and 4900 t for DDT, respectively, and the use of DDT due to dicofol application in the HRB was 220 t from 1984 to 2003. The usage of lindane in HRB was 109 t from 1991 to 2000. The results show that the highest technical HCH use （41800 t） in HRB was on maize, accounting for 38.3% of the total usage on all crops, followed by the use on wheat （28000 t, 25.7%） and on soybean （26600 t, 24.4%）. The highest DDT use （2300 t） was on soybean, accounting for 46.8% of the total usage on all crops, followed by the use on maize （1500 t, 31.3%） and on sorghum （600 t, 13.2%）. The major use of lindane was mainly on wheat. Gridded usage inventories of these three OCPs （organochlorine pesticides）, in HRB with a 1/6° latitude by 1/4° longitude resolution have been created by using different gridded cropland as surrogates. Some soil samples have also been collected in HRB. Data of usage and soil concentrations of 5： HCH in HRB match quite well to those in Shanghai region, and much higher soil concentration of 5： DDT in Shanghai region could be due to much heavier dicofol use in this region.

关键词： persistent organic pollutants (POPs) organochlorine pesticides (OCPs) DDT HCH lindane inventories Heilongjiang River Basin

Effect of Ce on castability,mechanical properties and electric conductivity of commercial purity aluminum

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China Foundry 2015年第4期12卷 277-284页

作者： Chang-lue Lü Heng-cheng Liao Ye Liu qi-gui Wang School of Materials Science and Engineering Southeast University Jiangsu Key Laboratory for Advanced Metallic Materials Materials Technology GM Global Powertrain Engineering

Effects of Ce addition on microstructure, castability （fluidity and hot tearing sensitivity）, mechanical properties and electric conductivity of commercial purity aluminum （CP-AI） were investigated through microstructure observation and performance tests. Results show that adding Ce in a CP-AI can considerably refine the grains, and has an important influence on the amount, crystallographic forms, and distribution of secondary phases. Addition of Ce also has a large impact on the fluidity and hot tearing sensitivity （HTS） of the CP-AI. With the addition of Ce from 0.1wt.% to 0.5wt.%, the fluidity of CP-AI is first increased remarkably and then decreased, and the HTS has an opposite response. The best castability of the studied alloys appears to be at 0.2wt.%-0.3wt.% Ce addition. The remarkable improvement in castability is attributed to the considerable refinement of grain structure. Ce addition can also lead to a significant rise in electric conductivity. The maximum conductivity of the as-cast CP-Al is 59.7% IACS with an addition of 0.2wt.%Ce. The T7 heat treatment can further improves the conductivity to 60.7% IACS. The Ce-induced evolution of the secondary phases is believed to be the mechanism for it.

关键词： cerium commercial purity aluminum microstructure castability mechanical property electric conductivity

Hydrophilicity Modification of Addition-cured Room Temperature Vulcanization Silicone Rubber

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Chinese Chemical Letters 2006年第4期17卷 533-536页

作者： Yun Xia qi Shi gui ZHAO Wei Feng JIANG Xin Xin YANG School of Material Science and Engineering Shandong University Jinan 250061

Allyl terminated polyether was used to improve the hydrophilicity of addition-cured room temperature vulcanization silicone rubber. With the increasing of the polyether, both the hydrophilicity and water absorbed of the vulcanizates were increased. The mechanical properties were also improved by adding the polyether. The result showed that 1.5wt% of the polyether provided the silicone rubber with proper hydrophilicity.

关键词： Allyl terminated polyether addition-cured silicone rubber room temperature vulcanization hydrophilicity mechanical properties.

Boosting Circularly Polarized Luminescence of Organic Conjugated Systems via Twisted Intramolecular Charge Transfer

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Research 2020年第1期2020卷 593-602页

作者： Junfeng Li Chenxi Hou Chao Huang Shanqi Xu Xuelei Peng qi qi Wen-Yong lai Wei Huang Key Laboratory for Organic Electronics and Information Displays Institute of Advanced Materials(IAM)Nanjing University of Posts and Telecommunications9 Wenyuan RoadNanjing 210023China School of Chemistry and Chemical Engineering Southeast UniversityNanjing 211189China Shaanxi Institute of Flexible Electronics(SIFE) Northwestern Polytechnical University(NPU)127 West Youyi RoadXi’an710072 ShaanxiChina

Realizing a high luminescence dissymmetry factor(g_(lum))is a paramount yet challenging issue in the research field of circularly polarized luminescence(CPL).Here,we reported a novel set of organic conjugated systems with twisted intramolecular charge transfer(TICT)characteristics based on conjugated o-carborane-binaphthyl dyads composing of binaphthyl units as chiral electron donors and o-carborane units as achiral electron acceptors,demonstrating intense CPL with large g_(lum) ***,single-crystalline o-1 exhibited a high-level brightness and a large g_(lum) factor as high as+0.13,whereas singlecrystalline o-2 processed a relatively low brightness with a decreased g_(lum) value *** significant diversity of CPL-active properties was triggered by the selective introduction of o-carborane units onto the binaphthyl *** from the large magnetic dipole transition moments in TICT states,the CPL activity of TICT o-carborane-based materials exhibited amplified circular *** study provides an efficient molecular engineering strategy for the rational design and development of highly efficient CPL-active materials.

关键词： materials circular conjugated

Discussion of Environmental Problem and Study of Environmental Impact on Steel Industry in China

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Journal of Iron and Steel Research International 2002年第2期9卷 24-27页

作者： ZHOU He-min LI gui-qi NIE Zuo-ren ZUO Tie-yong Central Iron&Steel Research Institute Beijing Polytechnic University Central-South University

The environmental conditions in steel industry were discussed in *** was also pointed out that it was necessary to reduce the quantity of waste generated and discharged by improving the raw material,energy structure and consumption rate,and reinforcing the waste control and *** the same time,the relevant mathematical models of environmental impact were set up on the basis of raw material consumption,energy consumption and waste generation and discharge in different technical routes of *** result showed that the production route of DR-iron clearly has more environmental advantages over that of BF-hot metal.

关键词： iron steel production route environmental impact mathematical model

Aquathermolysis of heavy crude oil with ferric oleate catalyst

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Petroleum Science 2018年第3期15卷 613-624页

作者： Yun-Rui Li qiu-Ye Li Xiao-Dong Wang lai-gui Yu Jian-Jun Yang Engineering Research Center for Nanomaterials Henan University

Oil-soluble catalysts could be of special significance for reducing the viscosity of heavy crude oil, because of their good dispersion in crude oil and high catalytic efficiency toward aquathermolysis. Ferric oleate was synthesized and applied as catalyst in the aquathermolysis reaction of Shengli heavy oil. It was found that ferric oleate was more efficient for heavy oil cracking than Co and Ni oleates. Besides, it was superior to oleic acid and inorganic ferric nitrate and achieved the highest viscosity reduction rate of up to 86.1%. In addition, the changes in the components of Shengli heavy oil before and after aquathermolysis were investigated by elemental analysis, Fourier transform infrared spectrometry, and ^1H nuclear magnetic resonance spectroscopy. Results indicated that ferric oleate contributed to a significant increase in the content of light components and decrease in the content of resin, N and S. The as-prepared ferric oleate showed good activity for reducing the viscosity and improving the quality of the heavy crude oil, showing promising application potential in aquathermolysis of heavy crude oil.

关键词： Heavy oil Viscosity reduction Aquathermolysis Ferric oleate Catalyst