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A new technology for hard-rock tunneling based on drilling and hydraulic impact breaking

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International Journal of Mining Science and Technology 2015年第6期25卷 1053-1058页

作者： Long Risheng Sun Shaoni Lian Zisheng Liao Yaoyao Qin Xiaofeng College of Mechanical Engineering Taiyuan University of Technology Shanxi Key Laboratory of Fully Mechanized Coal Mining Equipment shenyang puyue group School of Mechanical Engineering & Automation Northeastern University

In order to realize the safety, high efficiency and rapidity of hard rock tunneling, we propose the drilling &hydraulic impact hard-rock tunneling(DHIHT) technology and method. Based on the LS-DYNA explicit module and APDL programming, the key parameters of DHIHT, including drilling spacing and drilling radius, were investigated. The simulation results show that: the drilling spacing should not exceed0.20 m-larger distances weaken the actual breaking effect; the best drilling radius is about 0.035 m, larger or smaller distances would both decrease the effect of drilling-hole free surfaces. The field impact breaking experiments were conducted in Baitaizi township granite quarry, Jinzhou, Liaoning province,China. The experiment results indicate that DHIHT is a feasible method for hard-rock tunneling, but its efficiency still needs to be further optimized and improved.

关键词： Hydraulic impact breakingHard rock tunnelingBreaking mechanismNumerical simulationTechnology research

Experimental investigation of laser peening on TiAl alloy microstructure and properties

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Chinese Journal of Aeronautics 2015年第2期28卷 609-616页

作者： Qiao Hongchao Zhao Jibin Gao Yu shenyang Institute of Automation Chinese Academy of Science AVIC shenyang Liming Aero-engine (group) Corporation Ltd.

In order to study the effect of laser peening on microstructures and properties of TiAl alloy, TiAI alloy samples were treated by Nd：YAG laser system with the wavelength of 1064 nm, pulse-width of 18 ns, and pulse-energy of 0-10J. Surface micro-hardness, roughness, and microstructural characteristics were tested with micro-hardness tester, roughness tester and scanning electron microscope. Residual stress and pole figures were tested with X-ray diffraction and its high-temperature stability was analyzed. The experimental results show that surface micro-hardness increases by up to 30%, roughness increases to 0.37 lain, compressive residual stress increases to 337 MPa, and local texture and typical lamellar microstructure are generated. Residual stress, micro-hardness, and （002） pole figures tests are conducted, compressive residual stress value drops from 337 MPa to 260 MPa, hardness value drops from 377 HV0.2 to 343 HV0.2, and the （002） poles shift back to the center slightly. Laser peening improves microstructure and properties of TiAl alloy significantly.

关键词： High temperature stabilityLaser peening Microstructure Residual stress TiAl alloy

Isolation and characterization of the secondary wall-related SND1 gene in hawthorn

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Journal of Integrative Agriculture 2018年第9期17卷 2007-2014页

作者： CHEN Ke-qin GUO Yun-na SONG Meng-ru DAI Hong-yan ZHANG Zhi-hong group of Molecular Biology of Fruit Trees College of Horticulture Shenyang Agricultural University group of Fruit Germplasm Evaluation & Utilization College of Horticulture Shenyang Agricultural University

Secondary wall-associated NAC domain protein1 （SND1） is a key regulator directly regulating the expression levels of MYB46 and MYB83 in the regulation network for secondary wall synthesis, especially in plant fibres. In this study, a SND1 gene was isolated from hawthorn （Crataegus pinnatifida） and named as CpSND 1 because it has a conservative N-terminal DNA- binding domain with AtSNDI. Arabidopsis plants overexpressing CpSND1 had similar phenotypes as plants overexpressing AtSND1, including inhibited growth, upward-curling leaves, sepal dysplasia and sterility. In addition, overexpressing CpSNDI in Arabidopsis also induced the expression of downstream genes, including lignin, cellulose and xylan biosynthesis genes as well as MYB genes. Our results provided functional information of CpSND1 for future genetic engineering in hawthorn.

关键词： hawthorn transcription factor SND1 secondary cell wall transcriptional regulation

Laser cladding of NiCrSiB on Monel 400 to enhance cavitation erosion and corrosion resistance

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Rare Metals 2022年第12期41卷 4257-4265页

作者： Chun-Hua Zhang Chen-Liang Wu Song Zhang Yong-Feng Jia Meng Guan Jun-Zhe Tan Bin Lin School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China Nuclear Power Pump Industry Co. Ltd.Shenyang Blower Works Group CorporationShenyang 110869China

NiCrSiB modified layer was synthesized on Monel 400 by laser cladding,aiming at improving cavitation erosion and corrosion *** microstructure,chemical composition,phase constituents and microhardness were investigated using scanning electron microscope(SEM),energy-dispersive spectrometer(EDS),X-ray diffractometry(XRD) and microhardness *** cavitation erosion and corrosion behaviors of the modified layer were also evaluated using an ultrasonic vibrator and potentiodynamic polarization measurement,*** results show that by varying the laser fluence,a hard NiCrSiB modified layer with little airholes,cracks or other defects could be *** modified layer is ~1.1 mm in *** microstructure of the modified layer exhibits cellular dendrite,flake-like dendrite and multiple eutectic *** modified layer is mainly composed of γ-Ni solid solution,chromium carbide(Cr_(7)C_(3)and Cr_(23)C_(6)) and Ni_(3)*** microhardness of the modified layer is ~6.8 times that of Monel 400 *** the cavitation erosion and corrosion resistance of the modified layer are *** the cavitation erosion test,the cumulative erosion loss and erosion loss rate of the modified layer are one order of magnitude lower than that of the *** the electrochemical corrosion test,the corrosion potentials of the substrate and the modified layer are *** corrosion current densities of the substrate and the modified layer are 11.12 and 1.95 μA·cm^(-2),*** comparing their corrosion current densities,the corrosion resistance of the modified layer is about 5.7 times that of the substrate.

关键词： NiCrSiB Laser cladding Microstructure Cavitation erosion Corrosion

Effect of Solution Treatment on the Microstructure and Mechanical Properties of Sand-Cast Mg–9Gd–4Y–0.5Zr Alloy

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Acta Metallurgica Sinica(English Letters) 2018年第2期31卷 189-198页

作者： Jing-Li Li Na Zhang Xiao-Xuan Wang Di Wu Rong-Shi Chen The group of Magnesium Alloys and Their Applications Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China School of Materials Science and Engineering University of Science and Technology of China Hefei 230026 China AVIC shenyang Liming Aero--Engine group Corporation Shenyang 110043 China

Sand-cast Mg–9Gd–4Y–0.5 Zr（wt%） alloy was solution-treated at 500–565 ℃ in the time range of 0.5–30 h in air or vacuum to investigate its microstructure evolution and mechanical properties. The results showed that solution treatment temperature had a significant influence on the dissolving rate of eutectic phase and grain growth. Taken both of them into consideration, 510–520 ℃ was considered to be the optimum solution treatment temperature range for this *** should be noted that the trace（0.4–0.9 vol%） and insoluble cuboid-shaped phase precipitated during solution treatment was identified to be YH2, of which the hydrogen was thought to come from both the melting and solution heating *** addition, the 3D morphology and dissolving process of Mg24（Gd,Y）5 eutectic phases in the as-cast alloy were also discussed via in-situ observation under X-ray tomography.

关键词： Mg-Gd-Y-Zr alloy Solution treatment Microstructure Rare-earth hydride

Complicated hollow turbine blades and surface grain refinement process

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China Foundry 2010年第2期7卷 121-126页

作者： Peng Zhijiang Jia Shuqin Zhang Zehai Liu Yan AVIC shenyang Liming Aero-Engine （group） Corporation Ltd Shenyang 110043 shenyang Research Institute of Foundry Shenyang 110022 China

The control of grain size in superalloys is critical in the manufacture of gas turbine *** aim of the present research is to provide the technology for producing complicated hollow turbine blades with fine surface grains and better comprehensive mechanical *** melt superheating treatment and coating the internal surfaces of shell mould using a cobalt aluminate-bearing coating material,the in-uence of cobalt aluminate as inoculant on the surface grain sizes of turbine blade was studied with addition of cobalt aluminate:0,35%,45%-65% and 100% *** the same time,the effects of cooling circumstances of the blades on surface grain sizes were also experimented under the same addition of cobalt *** results showed that the melt superheating treatment plays a significant role in the grain size and carbide morphology;and fine surface grains were obtained when the internal surfaces of shell mould were coated using cobalt aluminate *** the addition of cobalt aluminate in coating is between 45%-65%,and the melt is poured into preheated shell moulds with fine silica sand as backing sand,the blades satisfied the surface grain size requirement is over 90%.In addition,comparisons of the surface grain size and the mechanical properties were also conducted between home-made and foreign-made blades.

关键词： complicated hollow turbine blades K465 alloy surface grain refinement melt superheating treatment

Synthesis and in vitro cytotoxicity of novel 1,4-disubstituted phthalazines

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Chinese Chemical Letters 2008年第1期19卷 29-32页

作者： Xin Zhai Juan Li Lei He Su Zheng Yao Bin Zhang Ping Gong School of Pharmaceutical Engineering Shenyang Pharmaceutical University Shenyang 110016 China shenyang No. 1 Pharmaceutical Factory Northeast Pharmaceutical Group Co. Ltd. Shenyang 110023 China

Eight novel 1,4-disubstituted phthalazines （7-14） were designed and synthesized. The structures of all the synthesized compounds were confirmed by IR,1H NMR, 13C NMR, MS and elemental analysis. Their in vitro cytotoxicity against cancer cell lines （Bel-7402 and HT- 1080） were evaluated by standard MTT assay. Among them, compounds 9 and 11 exhibited more potent cytotoxicity than cisplatin. 2007 Ping Gong. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Phthalazine derivatives Synthesis Cytotoxicity

Surface hardening of titanium alloys by oxygen-diffusion-permeation

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中国有色金属学会会刊：英文版 2003年第1期13卷 73-77页

作者：马红岩王茂才张松辛公春魏政 State Key Laboratory for Corrosion and Protection of Metals Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China School of Materials Science and Engineering Shenyang Polytechnic University Shenyang 110023 China shenyang Liming Aero-engine group Corporation Shenyang 110043 China

The surface oxygen-diffusion-permeation behaviors of Ti based alloys were investigated. MEF4A optical microscopy and HMV-2000 micro-hardness tester were employed to characterize the microstructure and micro-hardness of the oxygen-permeated alloys. The results show that the micro-hardness of Ti based alloys are sharply enhanced by the permeation of oxygen. The microstructure and micro-hardness of oxygen-permeated layer are strongly related to the oxygen-diffusion-permeation techniques. The solid solution of oxygen in α phase can improve the transformation temperature from α phase to β phase and enlarge the region of α phase so as to improve the micro-hardness of surface layer. Therefore, surface oxygen-diffusion-permeation would be a feasible method to reinforce Ti based alloys based on the solid solution of oxygen in α-Ti. At last, a diffusion-solution model was put forward.

关键词：钛基合金表面强化氧扩散渗透

Knowledge about non-invasive diagnostic tests for varices in liver cirrhosis:A questionnaire survey to the Gastroenterology Branch of the Liaoning Medical Association,China

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Gastroenterology Report 2016年第2期4卷 141-147,I0002,I0003页

作者： Xingshun Qi Xiaozhong Guo Hongyu Li Xu Liu Han Deng Liver Cirrhosis Study group Department of GastroenterologyGeneral Hospital of Shenyang Military AreaShenyangLiaoningChina

Background and aims:Due to the invasiveness of upper gastrointestinal endoscopy,non-invasive diagnostic tests for varices in liver cirrhosis have been widely established by numerous studies.A questionnaire survey,which was aimed at understanding the current knowledge about non-invasive diagnostic tests for varices in liver cirrhosis,was distributed among the members of Gastroenterology Branch of the Liaoning Medical ***:A questionnaire assessing the knowledge about non-invasive diagnostic tests for varices was sent to 42 members who participated in the entire ninth *** were from 33 hospitals in 13 cities of Liaoning Province,***:Overall,97.6%(41/42)of participants responded to the questionnaire.A majority of participants were chief physicians(85.4%),had>20 years of experience in clinical work of digestive diseases(80.5%)and worked at tertiary hospitals(97.6%).In 46.3%of participants’departments,there were>200 patients with liver cirrhosis and gastroesophageal varices admitted every *** 90.2%of participants’departments,upper gastrointestinal endoscopy was regularly employed for the diagnosis of gastroesophageal *** six(15%)participants often used non-invasive diagnostic tests for varices in clinical ***(75%)participants knew at least one non-invasive diagnostic test for *** knowledge of at least one non-invasive diagnostic test was significantly associated with the number of cirrhotic patients with varices(P¼0.038)or the regular use of gastrointestinal endoscopy to diagnose varices(P¼0.022).Conclusions:This questionnaire survey suggested that non-invasive diagnostic tests for varices in liver cirrhosis were rarely or never used in clinical practices in Liaoning Province,***,non-invasive indexes should be further explored in a well-designed multi-center observational study.

关键词： liver cirrhosis varices portal hypertension non-invasive diagnostic tests questionnaire survey