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Microstructure evolution and superelasticity behavior of Ti-Ni-Hf shape memory alloy composite with multi-scale and heterogeneous reinforcements

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Journal of Materials Science & Technology 2020年第7期42卷 113-121页

作者： Xiaoyang Yi Bin Sun Weihong gao Xianglong Meng zhiyong gao Wei Cai Liancheng Zhao School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China

In the present study,the in-situ TiB whisker was introduced into the Ti-Ni-Hf shape memory alloy composite by the in-situ reaction of the Ti-Ni-Hf alloy powder and TiB2 ***(Ti,Hf)2 Ni phase also precipitated,accompanied with the formation of TiB ***,the residual TiB2 particles can be observed,as the TiB2 content was higher than 0.7 wt%.Thereinto,the larger scale reinforcements constituted the quasi-continuous network *** smaller scale reinforcements distributed in the interior of the network *** two-scale reinforcements showed the uniform distribution at macroscopic level and inhomogeneous distribution at microscopic *** single stage B19?B2 martensitic transformation occurred in the Ti-Ni-Hf *** addition,the martensitic transformation temperatures continuously decreased with the increased TiB2 content owing to the compositional and mechanical *** moderate TiB2 addition not noly enhanced the matrix strength,but also significantly improved the *** excellent superelaticity with the completely recoverable strain of 4%can be obtained in the Ti-Ni-Hf composite containing 0.7 wt%TiB2.

关键词： Ti-Ni-Hf composite Shape memory alloy Microstructure Martensitic transformation High temperature superelasticity

Effect of calcium ions on CO_2 corrosion of 3Cr low-alloy steel

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Acta Metallurgica Sinica(English Letters) 2011年第5期24卷 373-380页

作者： Zhijun JIA Cuiwei DU zhiyong LIU Jin gao Xiaogang LI Corrosion and Protection Center University of Science and Technology Beijing Beijing 100083 China

The effect of calcium ions on the corrosion behavior of 3Cr low-alloy steel in CO2- containing sodium chloride solution was investigated by immersion test and electrochemical measurements. It is found that with the addition of Ca2＋ to CO2-containing solution, the crazing level of the corrosion scale on the specimen is much slighter than that of the specimen immersed in solution without Ca2＋. The pitting on the surface of the specimens immersed in the solution with Ca2＋ is relatively small and distributes uniformly all over the surface. The significant change in the anodic polarization curve is attributed to the deposition of the CaCO3. CaCO3 deposits on the specimen surface and gives a protection to the metal substrate. And with the anodic proceeding, the concentration of H＋ in the solution increases. The CaCO3 deposition dissolves in the low pH solution and the protection effect disappears.

关键词： Steel Corrosion Corrosion scale Polarization EIS SEM

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新型三段式粗颗粒浮选柱内流场数值模拟

中国有色金属学报 2024年第8期34卷 2801-2818页

作者：彭建孙伟沈政昌韩海生晋应升肖遥高志勇孙磊罗远家中南大学资源加工与生物工程学院长沙410083 北京矿冶科技集团有限公司矿物加工科学与技术国家重点实验室北京102628

本文对一种新型三段式粗颗粒浮选柱内流场特性进行了研究,结果表明,稳流板的加入可增强粗颗粒浮选柱内流体的湍动能和湍流耗散率,促进气泡和粗颗粒的相互作用以及湍动能、湍流耗散率和液相速度的均匀分布,从而利于矿化气泡的输送。射流... 详细信息

本文对一种新型三段式粗颗粒浮选柱内流场特性进行了研究,结果表明,稳流板的加入可增强粗颗粒浮选柱内流体的湍动能和湍流耗散率,促进气泡和粗颗粒的相互作用以及湍动能、湍流耗散率和液相速度的均匀分布,从而利于矿化气泡的输送。射流管个数的增加使粗颗粒浮选柱内湍动能和湍流耗散率分布趋向于均匀。对称的4个射流管可显著改善流场分布,形成的漩涡促进了气泡与颗粒的相互作用,稳流板使气泡速度分布均匀。浮选柱内湍动能随着上升水量和充气量的增加而增大,稳流板作用明显。上升水量对稳流板上下方区域湍流耗散率的影响呈梯级分布,可实现底部紊流矿化、中部紊流−稳流转变、上部静态流态化浮选的三段式流体环境,利于粗颗粒矿物浮选的回收。

关键词：浮选柱流场特性湍动能湍流耗散率计算流体动力学

双模盾构在全断面硬岩施工中管片定位桩技术研究

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江苏建筑 2024年第2期 73-76页

作者：张强高志勇吕晨熙中建四局土木工程有限公司广东深圳518000 江苏省安捷岩土工程有限公司江苏徐州221000

文章结合深惠城际铁路项目在全断面硬岩盾构施工中管片上浮的预防措施,引进管片固定桩,通过现场应用分析其可行性,并在实际工程应用中获得了良好的效益,可为以后盾构在全断面硬岩中的施工提供相应的借鉴。

关键词：盾构管片抗上浮管片固定桩

双模(EPB/TBM)盾构模式转换技术工程实践

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江苏建筑 2024年第1期 82-85页

作者：张强高志勇吕晨熙中建四局土木工程有限公司广东深圳518000 江苏省安捷岩土工程有限公司江苏南京221000

双模盾构机为地质起伏变化较大的盾构隧道工程而设计,通过对平衡模式的切换来适应不同地质环境下盾构的高效施工掘进。深惠城际平湖站至凤岗站区间因具有前段、后段为上软下硬地质,中段为全断面岩层地质的特点而采用EPB/TBM双模盾构施工... 详细信息

双模盾构机为地质起伏变化较大的盾构隧道工程而设计,通过对平衡模式的切换来适应不同地质环境下盾构的高效施工掘进。深惠城际平湖站至凤岗站区间因具有前段、后段为上软下硬地质,中段为全断面岩层地质的特点而采用EPB/TBM双模盾构施工,其间,需要切换模式4次。文章就盾构机模式切换的方法进行系统的阐述。

关键词：双模盾构机 EPB/TBM 模式转换施工技术

Lithofacies paleogeography restoration and its significance of Jurassic to Lower Cretaceous in southern margin of Junggar Basin,NW China

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Petroleum Exploration and Development 2022年第1期49卷 78-93页

作者： gao zhiyong SHI Yuxin FENG Jiarui ZHOU Chuanmin LUO Zhong Petroleum Geology Research and Laboratory Center PetroChina Research Institute of Petroleum Exploration and DevelopmentBeijing 100083China State Key Laboratory of Enhanced Oil Recovery Beijing 100083China

In view of the difficulties in the study of lithofacies paleogeography and the low reliability of the distribution range of sedimentary sand bodies in the prototype basin caused by less deep drilling, complex seismic imaging and low degree of exploration in the southern margin of Junggar Basin, NW China. A new method based on the source to sink idea was used to restore lithofacies paleogeography and predict glutenite distribution. In the restoration, apatite fission track age was used to define range and uplift time of macro-provenance;the range of provenance area and the migration process of lake shoreline were restored based on the quantitative relationship between gravel diameter and transportation distance, tectonic shortening and other geological parameters;drilling cores and field outcrop sedimentary structures were analyzed, and a series of maps of lithofacies paleogeographic evolution and distribution range of glutenite bodies were compiled. It is concluded that from Early Jurassic to Early Cretaceous, in the southern margin of Junggar Basin, the provenance area gradually expanded from south to north, the lake basin expanded, shrunk and expanded, and the paleoclimate changed from humid to drought to humid. The western section always had proximal fan delta deposits from the southern ancient Tianshan provenance developed, and in the middle and eastern sections, the provenance areas evolved from far source to near source, mainly river-delta, braided delta, fan delta and other sediments developed. The boundary between provenance areas of the western and middle sections is speculated to be Hongche fault zone. In an angle open to the northwest with the current basin edge line, the restored ancient lake shoreline controlled the heterogeneity of reservoirs in the delta plain belt and delta front belt on its both sides. The ancient lake shoreline, current stratigraphic denudation line and current basin margin line limit the types and scope of favorable ***

关键词： southern margin of Junggar Basin deep lower assemblage Jurassic Cretaceous provenance lake shoreline lithofacies paleogeography favorable sandbody distribution

Ethylenediamine tetramethylenephosphonic acid as a selective collector for the improved separation of chalcopyrite against pyrite at low alkalinity

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International Journal of Mining Science and Technology 2023年第7期33卷 873-882页

作者： Jianjun Wang gaogui Jing Renji Zheng Zijie Huang Wei Sun zhiyong gao School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China Key Laboratory of Hunan Province for Clean and Efficient Utilization of Strategic Calcium-containing Mineral Resources Central South UniversityChangsha 410083China Hunan International Joint Research Centre for Efficient and Clean Utilization of Critical Metal Mineral Resources Central South UniversityChangsha 410083China

Chalcopyrite is the main Cu-containing mineral and cannot be separated well from pyrite using traditional xanthate collectors with large amounts of lime depressant, resulting in difficulties of the tailing treatment and associated precious metals recovery. Therefore, in this study, the green and odourless ethylenediamine tetramethylenephosphonic acid(EDTMPA) was introduced as a novel chalcopyrite collector. Flotation results from the binary mineral mixture and real ore demonstrated that EDTMPA could realize the selective separation of chalcopyrite from pyrite relative to ethyl xanthate(EX) without any depressants within the wide p H range of 6.0–11.0, and might replace the traditional high-alkaline lime process. Electrochemical and Fourier transform infrared spectra measurements indicated that the difference in adsorption performance of EDTMPA on chalcopyrite and pyrite was larger than that of EX, suggesting a better selectivity for EDTMPA. Density functional theory calculations demonstrated that there were stronger chemical bonds between P—O groups of EDTMPA and the Fe/Cu atoms on chalcopyrite in the form of a stable six-membered ring. Crystal chemistry calculations further revealed that the activity of metal atoms of chalcopyrite was higher than that of pyrite. Therefore, these basic theoretical results and practical application provide a guidance for the industrial application of EDTMPA in chalcopyrite flotation.

关键词： Chalcopyrite Pyrite Flotation Ethylenediamine tetramethylenephosphonic acid Collector

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桥梁空心薄壁高墩预制横隔板应用研究

建筑机械化 2024年第10期45卷 106-109页

作者：岳喜梅李超高智勇伊犁哈萨克自治州交通建设工程质量监督执法支队中铁一局集团有限公司第三工程分公司

横隔板是保障空心薄壁高墩墩身稳定性的重要结构，通过对新疆北天山高寒山区G577精伊公路精斯格布拉克特大桥变截面空心薄壁高墩横隔板施工特点、工艺、方法及实践等方面进行总结、分析和研究，提出了一种新型的横隔板施工工艺，并在对... 详细信息

横隔板是保障空心薄壁高墩墩身稳定性的重要结构，通过对新疆北天山高寒山区G577精伊公路精斯格布拉克特大桥变截面空心薄壁高墩横隔板施工特点、工艺、方法及实践等方面进行总结、分析和研究，提出了一种新型的横隔板施工工艺，并在对该工艺施工条件下的横隔板的施工方法和安全、质量控制措施进行了分析和总结，为今后高墩横隔板施工提供可借鉴施工经验。

关键词：预制混凝土盖板横隔板空心薄壁高墩施工工艺质量控制

Dew measurement and estimation of rain-fed jujube (Zizyphus jujube Mill) in a semi-arid loess hilly region of China

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Journal of Arid Land 2017年第4期9卷 547-557页

作者： WANG Xing gao zhiyong WANG Youke Wang Zhi JIN Shanshan Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water Resources Department of Water Conservancy Yangling Vocational & Technological College College of Water Resources and Architectural Engineering Northwest A&F University Department of Earth and Environmental Sciences California State University

Dew is an important water source for plants in arid and semi-arid regions. However, information on dew is scarce in such regions. In this study, we explored dew formation, amount, and duration of rain-fed jujube（Zizyphus jujube Mill） trees in a semi-arid loess hilly region of China（i.e., Mizhi County）. The data included dew intensity and duration, relative humidity, temperature, and wind speed measured from 26 July to 23 October, 2012 and from 24 June to 17 October, 2013 using a micro-climate system（including dielectric leaf wetness sensors, VP-3 Relative Humidity/Temperature Sensor, High Resolution Rain Gauge, and Davis Cup Anemometer）. The results show that atmospheric conditions of relative humidity of 〉78% and dew point temperature of 1°C–3°C are significantly favorable to dew formation. Compared with the rainfall, dew was characterized by high frequency, strong stability, and long duration. Furthermore, heavy dew accounted for a large proportion of the total amount. The empirical models（i.e., relative humidity model（RH model） and dew point depression model（DPD model）） for daily dew duration estimation performed well at 15-min intervals, with low errors ranging between 1.29 and 1.60 h, respectively. But it should be noted that the models should be calibrated firstly by determining the optimal thresholds of relatively humidity for RH model and dew point depression for DPD model. For rain-fed jujube trees in the semi-arid loess hilly regions of China, the optimal threshold of relative humidity was 78%, and the optimal upper and lower thresholds of dew point depression were 1°C and 5°C, respectively. The study further demonstrates that dew is an important water resource that cannot be ignored for rain-fed jujube trees and may affect water balance at regional scales.

关键词： dew formation dew amount dew duration jujube plantation empirical models Loess Plateau