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Selective recovery of lithium from simulated brine using different organic synergist

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Chinese Journal of Chemical Engineering 2019年第2期27卷 335-340页

作者： Huifang Li Lijuan Li Xiaowu Peng Lianmin ji Wu Li Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources Qinghai Institute of Salt Lakes Chinese Academy of Sciences Key Laboratory of Salt Lake Resources Chemistry of qinghai Province University of Chinese Academy of Sciences qinghai University

The organic synergists, including Octanol, ethyl acetate(EA), butyl acetate(BA), methyl isobutyl ketone(MIBK),diisobutyl ketone(DIBK), N,N-bis(2-ethylhexyl) acetamide(N523) and 8-hydroxylquiolate, were added to the TBP–FeCl_3 extraction system to extract lithium from brine. The effects of concentration of organic synergist and total organic extractant, molar ratio of Fe/Li, phase ratio, counter-current extraction and the acidity of stripping agent on lithium extraction were investigated to optimize the extraction conditions. Under the optimize conditions, the results of counter-current extraction showed the mixed extraction system was the preponderance on the lithium extraction. Especially the separation of lithium in organic phase and aqueous phase and the separation mass ratio of Mg/Li increased greatly. An extraction mechanism was proposed based on the analysis of FT-IR spectra and Raman spectra.

关键词： Organic synergist Lithium extraction Mixed extraction system Mechanism

基于相对分子质量和热性质的改性沥青微观性能研究

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建筑材料学报 2018年第1期21卷 159-164页

作者：周燕吉鹏飞张凯李美东管青海天津城建大学天津市软土特性与工程环境重点实验室天津300384 安徽省交通规划设计研究总院股份有限公司桥梁工程科技分公司安徽合肥230000 天津市赛英工程技术咨询有限公司天津300051 天津城建大学天津市土木建筑结构防护与加固重点实验室天津300384

在90#基质沥青中加入一定比例的SBS,SBR,稳定剂和糠醛抽出油,分别制备成4种改性沥青并对其进行旋转薄膜烘箱试验和压力老化试验,得到短期老化和长期老化状态下的沥青样品.采用凝胶渗透色谱试验、差示扫描量热试验和热重试验,对改性沥青... 详细信息

在90#基质沥青中加入一定比例的SBS,SBR,稳定剂和糠醛抽出油,分别制备成4种改性沥青并对其进行旋转薄膜烘箱试验和压力老化试验,得到短期老化和长期老化状态下的沥青样品.采用凝胶渗透色谱试验、差示扫描量热试验和热重试验,对改性沥青样品相对分子质量和热性质进行研究.结果表明:单掺SBR的改性沥青样品结构最不稳定,耐老化性能最差;稳定剂组和糠醛抽出油组改性沥青样品在老化过程中的大分子分解和小分子聚合得到了抑制,温度稳定性得到了提高;4种改性沥青样品在升温过程中质量损失主要分为小于200℃,200~420℃及420~550℃这3个阶段,其中第3个阶段反应最剧烈,质量损失速率最大.

关键词：道路工程应力吸收层改性沥青热性质热老化

1978-2016年青藏高原湖冰物候时空变化特征及其影响因素分析

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长江流域资源与环境 2024年第5期33卷 1089-1098页

作者：张克新赵莉汪田归曹立国彭娇婷杜建雄纪燕贵州财经大学管理科学与工程学院贵州贵阳550025 陕西师范大学地理科学与旅游学院陕西西安710119 贵州财经大学科研处贵州贵阳550025

湖冰物候是反映气候变化的灵敏指示器。基于青藏高原126个湖泊1978~2016年湖冰物候数据集和气象数据,对青藏高原湖泊湖冰物候的时空变化特征及其影响因素进行分析。结果表明:(1)在全球变暖背景下,青藏高原1978~2016年湖冰物候指数的变... 详细信息

湖冰物候是反映气候变化的灵敏指示器。基于青藏高原126个湖泊1978~2016年湖冰物候数据集和气象数据,对青藏高原湖泊湖冰物候的时空变化特征及其影响因素进行分析。结果表明:(1)在全球变暖背景下,青藏高原1978~2016年湖冰物候指数的变化特征呈现出结冰时间显著推迟、融化时间显著提前、冰期显著缩短的变化趋势。(2)青藏高原湖冰物候指数变化趋势的空间差异较为显著,其中大多数湖泊的结冰时间、融化时间和冰期持续时间呈现出显著提前、推后和缩短趋势,仅有少数湖泊的湖冰物候指数变化趋势不显著。(3)青藏高原湖冰物候指数空间分布差异显著,从南到北呈现出湖泊结冰日期提前、融冰日期推迟、冰期持续时间延长的分布模式。(4)温度是影响湖冰物候指数的关键因素;降水、纬度和湖泊面积则对开始日结冰日和完全结冰日具有显著影响;开始融化日和完全融化日则主要受到风速、纬度和海拔的共同作用;而冰期和完全结冰期的长短则主要受到风速、降水、纬度和海拔的影响。因此,青藏高原湖冰物候的变化是气候变化和湖泊自身因素相互作用所导致的。

关键词：湖冰物候时空变化影响因素青藏高原

拉萨地块东部石炭——二叠系地层碎屑锆石年代学研究及启示

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西藏科技 2024年第1期46卷 24-39,46页

作者：吕龙颜家强吉风宝西藏自然科学博物馆拉萨850000

拉萨地块东部连续出露石炭—二叠系海相地层,研究其物源对揭示松多古特提斯洋演化过程具有重要意义。文章对工布江达娘蒲和林芝龙得地区石炭—二叠系地层开展碎屑锆石年代学研究,定年结果表明该套地层最年轻的年龄簇为314 Ma~322 Ma,指... 详细信息

拉萨地块东部连续出露石炭—二叠系海相地层,研究其物源对揭示松多古特提斯洋演化过程具有重要意义。文章对工布江达娘蒲和林芝龙得地区石炭—二叠系地层开展碎屑锆石年代学研究,定年结果表明该套地层最年轻的年龄簇为314 Ma~322 Ma,指示其沉积时代不早于晚石炭世。综合对比前人报道的澳大利亚Canning和Perth盆地石炭—二叠系地层碎屑锆石年龄谱、拉萨地块内松多古特提斯洋演化岩浆作用记录和增生杂岩碎屑锆石年龄谱,笔者认为该套地层中石炭纪年龄的碎屑锆石主要来源于松多古特提斯洋演化过程中岩浆作用;工布江达娘蒲松多群(AnOs)地层与直孔—松多地区的松多组(C2P1s)为同一套地层,是松多古特提斯洋增生杂岩的一部分;林芝龙得地区诺错组(C1n)地层与当雄来姑组(C2P1I)地层类似,是松多古特提斯洋边缘稳定沉积。

关键词：青藏高原拉萨地块晚古生代松多群诺错组

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苞叶雪莲化学成分及药理作用研究进展

中国民族民间医药 2024年第15期33卷 75-88页

作者：张胜男王素娟德吉西藏大学生态环境学院生态学系西藏拉萨850000

苞叶雪莲(Saussurea obvallata)是青藏高原地区特有的菊科风毛菊属植物,具有清热解毒、抗炎镇痛、通经活血等功效,是中国西藏、印度、巴基斯坦等地的传统药用植物。目前针对苞叶雪莲的现代药理学研究较少。苞叶雪莲的化学成分包括黄酮... 详细信息

苞叶雪莲(Saussurea obvallata)是青藏高原地区特有的菊科风毛菊属植物,具有清热解毒、抗炎镇痛、通经活血等功效,是中国西藏、印度、巴基斯坦等地的传统药用植物。目前针对苞叶雪莲的现代药理学研究较少。苞叶雪莲的化学成分包括黄酮类、萜类、脂肪酸、生物碱等,现代药理学研究证实这些成分具有抗炎、抗氧化、抗肿瘤、调节免疫、保护心脑血管等多种作用。文章对苞叶雪莲的化学成分和药理作用研究进展进行了综述,为苞叶雪莲的进一步研究和新药开发提供参考。

关键词：苞叶雪莲传统藏药化学成分药理作用

同方期刊数据库博看期刊评论

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青海省三江源生态功能区文旅融合发展实证

湖北农业科学 2024年第3期63卷 1-7页

作者：张杰季海瑞张剑勇青海师范大学经济管理学院西宁810016 青海师范大学高原与可持续发展研究院西宁810016

为探究三江源生态功能区文旅融合发展的可行性,实现高质量文旅发展,基于文化、旅游耦合协调机理,采用2010—2020年的面板数据,通过耦合协调模型,从时间与区域分布对三江源生态功能区文旅产业耦合协调发展水平进行实证分析。结果表明,201... 详细信息

为探究三江源生态功能区文旅融合发展的可行性,实现高质量文旅发展,基于文化、旅游耦合协调机理,采用2010—2020年的面板数据,通过耦合协调模型,从时间与区域分布对三江源生态功能区文旅产业耦合协调发展水平进行实证分析。结果表明,2010—2020年,三江源生态功能区文化产业和旅游产业的发展整体呈上升趋势,但文化产业的发展滞后于旅游产业;从区域分布看,各州文化产业和旅游产业发展不同步,东、西部发展不协调。三江源生态功能区文旅融合总体上历经中度失调—轻度失调—濒临失调的阶段,随着各州耦合协调度的不断增长,耦合协调水平差距在缩小,但大部分州仍处于低水平阶段。三江源生态功能区东部地区文旅融合水平优于西部地区,黄南州依靠资源优势和地理条件,产业融合发展最优,达到中水平耦合协调。三江源生态功能区文化产业和旅游产业相互配合、相互支撑,文旅融合有利于促进产业间的转型升级,帮助两大产业提质增效。

关键词：文化产业旅游产业文旅融合三江源生态功能区青海省

Spatial variability and its main controlling factors of the permafrost soil-moisture on the northern-slope of Bayan Har Mountains in qinghai-Tibet Plateau

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Journal of Mountain Science 2017年第12期14卷 2406-2419页

作者： cao wei sheng yu wu ji-chun li jing state key laboratory of frozen soil engineering northwest institute of eco-environment and resourceschinese academy of sciences

The soil moisture movement is an important carrier of material cycle and energy flow among the various geo-spheres in the cold ***, this research takes the north slope of Bayan Har Mountains in qinghai-Tibet Plateau as a case *** present study firstly investigates the change of permafrost moisture in different slope positions and depths. Based on this investigation, this article attempts to investigate the spatial variability of permafrost moisture and identifies the key influence factors in different terrain conditions. The method of classification and regression tree(CART) is adopted to identify the main controlling factors influencing the soil moisture movement. The relationships between soil moisture and environmental factors are revealed by the use of the method of canonical correspondence analysis(CCA). The results show that: 1) Due to the terrain slope and the freezing-thawing process, the horizontal flow weakens in the freezing period. The vertical migration of the soil moisture movement strengthens. It will lead to that the soil-moisture content in the up-slope is higher than that in the down-slope. The conclusion is contrary during the melting period. 2) Elevation, soil texture, soil temperature and vegetation coverage are the main environmental factors which affect the slopepermafrost soil-moisture. 3) Slope, elevation and vegetation coverage are the main factors that affect the slope-permafrost soil-moisture at the shallow depth of 0-20 cm. It is complex at the middle and lower depth.

关键词： qinghai-Tibet Plateau Northern-slope of Bayan Har Mountains Permafrost Soil moisture Spatial variability Controlling factors

Modern pollen rain in the Lake qinghai basin, China

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Science China Earth Sciences 2009年第10期52卷 1510-1519页

作者： SHANG Xue LI XiaoQiang AN ZhiSheng ji Ming ZHANG HongBin State Key Lab of Loess&Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an 710075China Graduate University of Chinese Academy of Sciences Beijing 100049China

Lake qinghai is the largest inland brackish lake in China and lies within the NE Tibetan Plateau. Our study shows that pollen assemblages in each vegetation belt are significantly correlated with the vegetation types of this area. Among the herbaceous and shrubby pollen assemblages, Artemisia is over-represented, while Poaceae, Cyperaceae and Polygonaceae are under-represented. Artemisia/ Chenopodiaceae (A/C) ratios with the regional vegetation characteristic can be used as a proper index to reconstruct the history of vegetation and climate in Lake qinghai basin. Modern pollen in the lake mainly comes from the nearby vegetation, controlled by the directions and velocity of the wind. The distribution of modern pollen in Lake qinghai tends to be similar in most part of the lake. The difference of pollen sedimentation process in the lake can be potentially influenced by the focusing function of the lake, river streams, and lake current.

关键词： Lake qinghai basin modern pollen pollen sources dominant factors

Subspecies in Przewalski's gazelle Procapra przewalskii and its conservation implication

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Chinese Science Bulletin 2013年第16期58卷 1897-1905页

作者： MARDAN Turghan jiANG ZhiGang GROVES Colin P YANG ji FANG HongXia Key Laboratory of Animal Ecology and Conservation Biology Institute of Zoology Chinese Academy of Sciences Key Laboratory of Biogeography and Bioresource in Arid Land Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Graduate School of Chinese Academy of Sciences Department of Archaeology and Anthropology Australian National University

Przewalski’s gazelle Procapra przewalskii is an endangered species endemic to China. A question remains about subspecific variation in this species. Skulls of Przewalski’s gazelle collected from its current remnant ranges around the qinghai Lake in combination with those collected prior to the 20th century were measured and analyzed using Hierarchical Cluster Analysis in order to clarify the question. Unexpectedly, P. p. diversicornis, extirpated from its historic range, has spread to the qinghai Lake region where it has replaced nominotypical P. p. przewalskii and is now restricted to a few small isolated populations around the lake. We discuss the causes of this unexpected replacement. In this study, we discuss the possibility of a new form, possibly a new subspecies, in the Guide Basin, adjacent to qinghai Lake; it is unclear whether the new form has long existed and was only discovered in recent years, or whether it evolved in recent times due to the geographical isolation and anthropogenic landscape features. The study sheds light on the processes of microevolution and subspeciation in Procapra przewalskii, and based on the findings, we propose measures for conservation strategies for Przewalski’s gazelle.

关键词：普氏原羚亚种保护青海湖地区濒危物种聚类分析普氏野马贵德盆地