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Hydrothermal synthesis of hydroxyapatite coating on the surface of medical magnesium alloy and its corrosion resistance

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Progress in Natural Science:Materials International 2021年第2期31卷 324-333页

作者： Shifeng Wen Xianglei Liu Jiahui Ding Yulai Liu ziting lan Zimeng Zhang Guangmeng Chen School of Mechanics and Civil & Architecture Northwestern Polytechnical University

The early corrosion control of biomedical magnesium alloy is an important measure to determine its good performance during implantation into human body. The deposition of calcium phosphate biological coating is the most effective solution at present. In this paper, hydroxyapatite（HAP） coating was hydrothermal synthesized on the surface of AZ31 B magnesium alloy, and the influence mechanism of hydrothermal synthesis temperature, time and solution concentration was investigated. The synthesis conditions and deposition mechanism of hydroxyapatite coating without DCPA（CaHPO4） were proposed. The surface morphology of the coating was observed by field emission electron scanning microscope（FESEM）. The types and contents of microelements in the material were analyzed by energy disperse spectroscopy（EDS）. Fourier transform infrared spectroscopy（FTIR） was used to analyze the functional group information of the coating surface. The corrosion resistance of different experimental groups was studied by electrochemical test. The results showed that when the calcium phosphate solution concentration was 0.1 mol/L and the calcium/phosphorus ratio was 1.67, the coating had better morphology structure and corrosion resistance, and the calcium/phosphorus ratio of HAP crystals reached 1.58, the epit of the prepared AZ31 B-HAP coating by bare metal increased from -1.51 V to -1.18 V, the impedance value reached 1.0×10～5Ω·cm2, and the early corrosion of magnesium alloy substrate was effectively delayed.

关键词： Medical magnesium alloy Hydroxyapatite coating Corrosion property Electrochemistry

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豫北平原浅层地下水资源可持续开发利用

地下水 2005年第4期27卷 229-231页

作者：兰自亭刘玉忠河南省地质矿产勘查开发局第一水文地质工程地质队河南新乡453002

豫北平原隶属黄河、海河两大流域,在平原区松散岩类中蕴藏着较丰富的地下水。随着工农业和城市化的发展,地下水资源的开发利用程度在逐步升高,合理地开发利用地下水资源的重要性日趋显著。主要论述了浅层含水岩组的特征、水动力条件、... 详细信息

豫北平原隶属黄河、海河两大流域,在平原区松散岩类中蕴藏着较丰富的地下水。随着工农业和城市化的发展,地下水资源的开发利用程度在逐步升高,合理地开发利用地下水资源的重要性日趋显著。主要论述了浅层含水岩组的特征、水动力条件、开发利用现状及与地下水开采相关的环境地质问题。分析了天然资源量的组成,说明了可采资源量的计算方法,指出有开采潜力区和超采区的分布。针对所存在的问题,提出了浅层地下水资源可持续开发利用的措施。

关键词：浅层地下水开发利用环境地质问题开采潜力

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地源热泵技术与深部地热供暖对比分析

中国煤炭地质 2020年第8期32卷 44-47页

作者：兰自亭郭精超尹红美刘瑾河南省地矿局第一地质环境调查院郑州450000 河南省煤田地质局三队河南新乡453004

目前河南省地热资源开发利用主要集中在中深层地热资源方面,开采方式以凿井取热为主,开采深度,大部分在800~1800m。详细介绍了土壤热泵技术、浅层地下水源热泵技术和中深层地下热水供暖技术,并结合工程实例进行了说明。通过调查统计与... 详细信息

目前河南省地热资源开发利用主要集中在中深层地热资源方面,开采方式以凿井取热为主,开采深度,大部分在800~1800m。详细介绍了土壤热泵技术、浅层地下水源热泵技术和中深层地下热水供暖技术,并结合工程实例进行了说明。通过调查统计与分析对比,认为浅层地热资源更具开发利用潜力。

关键词：中深层地热土壤源热泵系统水源热泵系统对比分析

Geochemical-geomorphological Evidence for the Provenance of Aeolian Sands and Sedimentary Environments in the Hunshandake Sandy land, Eastern Inner Mongolia, China

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Acta Geologica Sinica(English Edition) 2013年第3期87卷 871-884页

作者： LIU ziting YANG Xiaoping Key Laboratory of Cenozoic Geology and Environment Institute of Geology and Geophysics Chinese Academy of Sciences University of Chinese Academy of Sciences

Identifying the provenance of aeolian sediments in the Hunshandake Sandy land is of great importance for understanding the formation of the dune fields in the mid-latitudes and for deciphering information about desert＇s responses to global change. By determining the major and trace elements concentrations of aeolian sands in three grain size fractions from the central and western parts of the Hunshandake Sandy land, we systematically study the provenance and the depositional history of aeolian sands in this desert environment. Our results show that aeolian sands from the Hunshandake Sandy land are enriched in SiO2 and are depleted in many other elements compared to those of the Upper Continent Crust （UCC）. Variations of the immobile elements ratios like Zr/Hf, La/Yb, Th/Nb, La/Nb, lan/YbN, GdN/YbN are relatively large in the coarse and medium fractions but minor in the fine fractions. Eu anomalies are quite different in the coarse fractions, but mostly positive in the medium fractions and all negative in the fine fractions. Decreasing tendency of Zr concentrations from the west to the east in the Hunshandake Sandy land is evident in the coarse sands but rather weak in the fine grain size fractions. Our geochemical data indicate that the sources for the coarse and medium fractions of aeolian sands are diverse, influenced by local geology and geomorphology, while the fine sand fractions are more homogenous due to intensive mixture mainly by aeolian processes. Various ratios of immobile elements suggest that these sands should be sourced primarily from the surrounding mountains by fluvial/alluvial processes rather than from any remote territories. Aeolian sands with Ce negative anomalies are widely distributed in the Hunshandake Sandy land, indicating that aquatic environments have occurred extensively prior to the occurrence of the dune field.

关键词： sediment provenance trace element major element REE aeolian process geomorphology geochemistry dune

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大学毕业生面试服装设计方法研究

山东纺织科技 2018年第6期59卷 33-35页

作者：石云王澜关紫婷广东海洋大学寸金学院广东湛江524000

文章从大学毕业生对面试服装的需求出发,探讨了面试服装的设计方法和设计原则,总结了面试服装设计需要注意的问题,并设计制作了艺术设计专业和英语专业的面试服装,为相关设计工作提供一定的理论和实践参考。

关键词：大学毕业生面试服装设计方法研究