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低温风洞中液氮液滴的破碎特性模拟研究

西安交通大学学报 2024年第2期58卷 91-99页

作者：苗庆硕魏震陈佳军张海洋钟富豪郑勉刘秀芳西安交通大学能源与动力工程学院西安710049 中国空气动力研究与发展中心设备设计及测试技术研究所四川绵阳621000

为探究低温风洞中液氮液滴的破碎特性并阐明其破碎机理,基于耦合水平集流体体积函数(CLSVOF)方法,采用自适应局部网格加密技术,构建了二维液氮液滴破碎模型,对比了液氮液滴与常温液滴的形态演变规律,计算分析了韦伯数(We)对液氮液滴形... 详细信息

为探究低温风洞中液氮液滴的破碎特性并阐明其破碎机理,基于耦合水平集流体体积函数(CLSVOF)方法,采用自适应局部网格加密技术,构建了二维液氮液滴破碎模型,对比了液氮液滴与常温液滴的形态演变规律,计算分析了韦伯数(We)对液氮液滴形态、变形系数及时间特性的影响规律。模拟结果表明:液氮液滴的We高于常温液滴,且更容易发生变形和破碎;随着We的增大,液氮液滴依次发生袋状破碎、多模式破碎和剪切破碎;液滴迎风面和背风面的压差均随时间呈现先增大后减小的规律,发生转变的原因是袋状结构形成或边缘液滴颗粒脱落;不同液氮液滴破碎模式下,变形系数的变化规律差异明显;液氮液滴无量纲初始破碎时间随We的增大而减小,在0

关键词：低温风洞液氮液滴破碎特性破碎模式变形系数

3D dynamic motion of a dielectric micro-sphere within optical tweezers

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Opto-Electronic Advances 2021年第1期4卷 14-24页

作者： Jing Liu mian zheng zhengjun Xiong Zhiyuan Li Institute of Laser and Intelligent Manufacturing Technology South-Central University for NationalitiesWuhan 430074China China Ship Development and Design Center Wuhan 430064China School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640China

Known as laser trapping,optical tweezers,with nanometer accuracy and pico-newton precision,plays a pivotal role in single bio-molecule measurements and controllable motions of *** order to advance the flourishing applications for those achievements,it is necessary to make clear the three-dimensional dynamic process of micro-particles stepping into an optical *** this paper,we utilize the ray optics method to calculate the optical force and optical torque of a micro-sphere in optical *** the influence of viscosity force and torque taken into account,we numerically solve and analyze the dynamic process of a dielectric micro-sphere in optical tweezers on the basis of Newton mechanical equations under various conditions of initial positions and velocity vectors of the *** particle trajectory over time can demonstrate whether the particle can be successfully trapped into the optical tweezers center and reveal the subtle details of this trapping *** in a simple pair of optical tweezers,the dielectric micro-sphere exhibits abundant phases of mechanical motions including acceleration,deceleration,and *** studies will be of great help to understand the particle-laser trap interaction in various situations and promote exciting possibilities for exploring novel ways to control the mechanical dynamics of microscale particles.

关键词： optical tweezers 3D dynamic motion ray optics method Newton mechanical equations

Magnetostratigraphy and ^(230)Th dating of a drill core from the southeastern Qaidam Basin:Salt lake evolution and tectonic implications

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Geoscience Frontiers 2018年第3期9卷 943-953页

作者： An-Dong Chen mian-Ping zheng Hai-Tao Yao Kui Su Jian-Ming Xu MLR Key Laboratory of Saline Lake Resources and Environments Institute of Mineral ResourcesChinese Academy of Geological Sciences Institute of Geomechanics Chinese Academy of Geological Sciences

The Qarhan Salt Lake area is the Quaternary depocenter of the Qaidam Basin, and carries thick lacustrine sediments, as well as rich potassium and magnesium salt deposits. The abundant resources and thick sediments in this lake provide an ideal place for the study of biogas formation and preservation, salt lake evolution, and the uplift of the Tibetan Plateau. In this study, we attempt to construct a paleomagnetic and ^(230)Th age model and to obtain information on tectonic activity and salt lake evolution through detailed studies on a 1300-m-long drill core(15DZK01) from the northwestern margin of the Qarhan Salt Lake area(Dongling Lake). Based on gypsum ^(230)Th dating, the age of the uppermost clastic deposit was calculated to be around 0.052 Ma. The polarity sequence consist of 13 pairs of normal and reversed zones,which can be correlated with subchrons C2r.1r-C1n of the geomagnetic polarity timescale(GPTS 2012)(from ~2.070 Ma to ~0.052 Ma). Sedimentary characteristics indicate that Dongling Lake witnessed freshwater environment between ~ 2.070 Ma and 1.546 Ma. During this period, the sedimentary record reflects primarily lakeshore, shallow-water and swamp environments, representing favourable conditions for the formation of hydrocarbon source rocks. Between 1.546 Ma and ~ 0.052 Ma, the Dongling Lake was in sulphate deposition stage, which contrasts with the central Qarhan Salt Lake area, where this stage did not occur in the meantime. During this stage, Dongling Lake was in a shallow saltwater lake environment, but several periods of reduced salinity occurred during this stage. During the late Pleistocene at ~0.052 Ma, the Dongling Lake experienced uplift due to tectonic activity, and saltwater migrated through the Sanhu Fault to the central Qarhan Salt Lake area, resulting in the absence of halite deposition stage. The residual saline water was concentrated into magnesium-rich brine due to the lack of freshwater, and few potassium salt deposits occur in the Don

关键词： Qaidam Basin Magnetostratigraphy 230Th dating Salt lake evolution Tectonic activity

Characteristics and origin of a new type of polyhalite potassium ore in the Lower Triassic Jialingjiang Formation, Puguang area, northeastern Sichuan Basin, SW China

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Journal of Palaeogeography 2021年第1期10卷 112-124页

作者： Wen-Jun Shang mian-Ping zheng Yong-Sheng Zhang Jia-Ai Zhong En-Yuan Xing Yuan Peng Bao-Ling Gui Kong Li Institute of Mineral Resources Chinese Academy of GeosciencesBeijing 100037China Key Laboratory of Salt Lake Resources and Environment Ministry of Natural ResourcesBeijing 100037China Key Laboratory of Mineralization and Resource Evaluation Ministry of Natural ResourcesBeijing 100037China The 5th Detachment of Gold Force of the Chinese People's Armed Police Force Xi'an 710199Shaanxi ProvinceChina

A new type of polyhalite potassium ore(NTPPO) was found in the Lower Triassic Jialingjiang Formation, NE Sichuan Basin, SW China. It is water soluble, therefore can be exploited using the water-solution method, and is of great potential of economic value and research significance. Based on cores, thin sections, energy spectrum and SEM analyses, its microfeatures, macrofeatures and origin are discussed, and a genetic model is established to provide a scientific basis for future evaluation, prediction and exploration of potassium ore in the Sichuan Basin. It is proposed that the NTPPO was caused by storm activities:(1) the storm broke the original sedimentary polyhalite–gypsum beds, whose fragments were transported into the salt basin with high content of K+ and Mg2+;(2) in the basin, the polyhalite continued to be formed from gypsum by metasomatism with K-and Mg-rich brine;(3) during diagenesis, under high temperature and high pressure, K–Mg-rich brine from halite continued to replace anhydrite(or gypsum) to form polyhalite.

关键词： Puguang area Lower Triassic New type of polyhalite potassium ore Microfeatures and macrofeatures Storm event deposition

Classification and mineralization of global lithium deposits and lithium extraction technologies for exogenetic lithium deposits

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China Geology 2023年第4期6卷 547-566页

作者： mian-ping zheng En-yuan Xing Xue-fei Zhang Ming-ming Li Dong Che Ling-zhong Bu Jia-huan Han Chuan-yong Ye Key Laboratory of Saline Lake Resources and Environment(Ministry of Natural Resources) Institute of Mineral ResourcesChinese Academy of Geological SciencesBeijing 100037China China University of Mining and Technology(Beijing) Beijing 100083China

A reasonable classification of deposits holds great significance for identifying prospecting targets and deploying exploration. The world ’s keen demand for lithium resources has expedited the discovery of numerous novel lithium resources. Given the presence of varied classification criteria for lithium resources presently, this study further ascertained and classified the lithium resources according to their occurrence modes, obtaining 10 types and 5 subtypes of lithium deposits(resources) based on endogenetic and exogenetic factors. As indicated by surveys of Cenozoic exogenetic lithium deposits in China and abroad,the formation and distribution of the deposits are primarily determined by plate collision zones, their primary material sources are linked to the anatectic magmas in the deep oceanic crust, and they were formed primarily during the Miocene and Late Paleogene. The researchers ascertained that these deposits,especially those of the salt lake, geothermal, and volcanic deposit types, are formed by unique slightly acidic magmas, tend to migrate and accumulate toward low-lying areas, and display supernormal enrichment. However, the material sources of lithium deposits(resources) of the Neopaleozoic clay subtype and the deep brine type are yet to be further identified. Given the various types and complex origins of lithium deposits(resources), which were formed due to the interactions of multiple spheres, it is recommended that the mineralization of exogenetic lithium deposits(resources) be investigated by integrating tectono-geochemistry, paleoatmospheric circulation, and salinology. So far, industrialized lithium extraction is primarily achieved in lithium deposits of the salt lake, clay, and hard rock types. The lithium extraction employs different processes, with lithium extraction from salt lake-type lithium deposits proving the most energy-saving and cost-effective.

关键词： Exogenetic lithium deposit Endogenetic lithium deposit Deposit type Salt lake type Deep brine type Geothermal type Volcanic deposit type Clay type Supernormal supergene enrichment SGSP lithium extraction techology Invention patent Mineral resource exploration engineering

青藏高原扎布耶盐湖SZK01孔粘土矿物X射线粉晶衍射分析

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光谱学与光谱分析 2014年第11期34卷 3119-3122页

作者：张雪飞郑绵平中国地质科学院矿产资源研究所国土资源部盐湖资源与环境重点实验室北京100037

青藏高原具有独特的地质地理区位优势,并且是我国最大的盐湖分布区,在其晚第四纪湖相沉积中保存着丰富多彩的古环境信息,可为研究青藏高原对全球变化的响应提供崭新而翔实的科学依据。扎布耶盐湖位于青藏高原腹地北部,对于高精度研究青... 详细信息

青藏高原具有独特的地质地理区位优势,并且是我国最大的盐湖分布区,在其晚第四纪湖相沉积中保存着丰富多彩的古环境信息,可为研究青藏高原对全球变化的响应提供崭新而翔实的科学依据。扎布耶盐湖位于青藏高原腹地北部,对于高精度研究青藏高原更新世晚期以来古气候、古环境变化具有重要意义。选择扎布耶盐湖SZK01孔岩芯粘土矿物为主要研究对象,通过X射线粉晶衍射对其进行定性、定量分析。结果显示粘土矿物种类主要是伊利石(I)、伊利石/蒙皂石混层矿物(I/S)以及少量高岭石(K)和绿泥石(C)。按照粘土矿物种类和含量变化,并综合沉积物矿物组合特征以及δ18 O同位素结果,重建扎布耶盐湖115ka(千年)以来的古气候演化。将结果与扎布耶SZK02孔、格陵兰冰芯、古里雅冰芯δ18 O同位素结果对比,将扎布耶盐湖115ka以来划分为5个阶段:末次间冰期(115~75.5ka)、末次冰期早阶(75.5~60ka)、末次冰期间冰阶(60~30.1ka)、末次盛冰期(30.1~16.7ka)、冰消期和全新世(16.7ka以来),识别出H6-H16个Heinrich事件和71ka左右的暖事件,说明青藏高原在该时期气候变化具有全球性。特别的是在52~53ka左右,高岭石含量较低,δ18 O值急剧偏负,SZK02孔δ18 O也相应偏负,古里雅冰芯δ18 O也偏负,说明青藏高原该时段存在冷事件,命名为H5-1。通过该研究综合说明青藏高原在末次冰期早冰阶以来气候变化具有全球性,但也有一定的地域性。

关键词：扎布耶盐湖粘土矿物 XRD 古气候 Heinrich事件

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兑卤法从硫酸钠亚型盐湖卤水中制备碳酸锂

高校化学工程学报 2018年第2期32卷 472-477页

作者：高峰乜贞郑绵平新疆警察学院非传统安全研究所新疆乌鲁木齐830011 公安海警学院船艇指挥系浙江宁波315801 中国地质科学院矿产资源研究所国土资源部盐湖资源与环境研究重点开放实验室北京100037

为开发西藏硫酸钠亚型盐湖—扎北盐湖中的卤水锂资源,提出盐湖联合开发—碳酸盐型卤水与扎北富锂卤水兑卤提锂的新方法。实验以扎北高锂卤水(BI)为原料,扎布耶盐田富碳酸根卤水(BII)为天然沉淀剂,在不同温度(5~90℃)及兑卤比(V_(BII)/V_... 详细信息

为开发西藏硫酸钠亚型盐湖—扎北盐湖中的卤水锂资源,提出盐湖联合开发—碳酸盐型卤水与扎北富锂卤水兑卤提锂的新方法。实验以扎北高锂卤水(BI)为原料,扎布耶盐田富碳酸根卤水(BII)为天然沉淀剂,在不同温度(5~90℃)及兑卤比(V_(BII)/V_(BI)=0.5~2.5)条件下进行了碳酸锂混盐的兑卤沉淀。结果表明,在V_(BII)/V_(BI)=1.75、90℃条件下进行兑卤沉淀时,锂收率82.66%,碳酸锂含量88.25%。用该法所制的碳酸锂混盐利于后续提纯,经调浆水洗、烘干研磨后可获纯度高、分散性好的碳酸锂粉末。

关键词：扎北盐湖硫酸钠型卤水兑卤法碳酸锂

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一种反馈FDL结构竞争解决丢包率的研究

光子学报 2006年第8期35卷 1243-1247页

作者：郑勉邱昆凌云电子科技大学宽带光纤传输与通信网技术教育部重点实验室成都610054

对反馈FDL结构的光分组交换竞争解决方案建立了数学模型并进行了理论分析,推导出了在反馈FDL输入分组比输入光纤输入分组具有更高输出优先级时的系统丢包率公式,对系统丢包率与负载、输入光纤端口数和FDL数目的关系进行了数值计算和讨论... 详细信息

对反馈FDL结构的光分组交换竞争解决方案建立了数学模型并进行了理论分析,推导出了在反馈FDL输入分组比输入光纤输入分组具有更高输出优先级时的系统丢包率公式,对系统丢包率与负载、输入光纤端口数和FDL数目的关系进行了数值计算和讨论.结果表明由于FDL缓存分组的概率与输入分组负载的非线性关系导致了反馈FDL结构在低负载时对丢包率的改善非常明显,对高负载的改善却十分有限.随着FDL数目的增加,对系统丢包率的改善不会趋于一个极限值,这是与使用波长转换器进行竞争解决的不同之处,因此使用反馈FDL结构可以降低波长转换器的丢包率极限.

关键词：光分组交换竞争解决光纤延迟线丢包率

我国蒙新地区近40年来湖泊动态变化与气候耦合

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地球学报 2014年第4期35卷 463-472页

作者：闰立娟郑绵平中国地质科学院矿产资源研究所国土资源部盐湖资源与环境重点实验室北京100037 中国地质科学院北京100037

湖泊对气候变化有着敏感的反应,是气候变化的镜子。本文以RS和GIS技术为基础,从20世纪70年代、90年代、2000年前后和2010年前后四期Landsat遥感影像中提取了我国内蒙古和新疆所有湖泊信息,建立了蒙新地区湖泊空间数据库。一方面,用ArcGI... 详细信息

湖泊对气候变化有着敏感的反应,是气候变化的镜子。本文以RS和GIS技术为基础,从20世纪70年代、90年代、2000年前后和2010年前后四期Landsat遥感影像中提取了我国内蒙古和新疆所有湖泊信息,建立了蒙新地区湖泊空间数据库。一方面,用ArcGIS软件对研究区湖泊信息进行了统计和空间分析,从时间和空间上分析了蒙新地区湖泊从20世纪70年代至2010年前后近40年湖泊的动态变化情况;另一方面,选取了蒙新地区面积大于5 km2的所有湖泊,逐个分析其在四个时期的变化情况,并根据变化结果进行分区。从20世纪70年代至90年代,内蒙古东南部和新疆西部的湖泊呈现萎缩的趋势,其余地区则在扩张;20世纪90年代至2000年前后,内蒙古东南部湖泊呈现萎缩的趋势,内蒙古北部和新疆全区湖泊呈现扩张的趋势;从2000年前后至2010年前后,内蒙古东北部和新疆西部的湖泊呈现萎缩的趋势,其余地区湖泊呈现扩张的趋势。在全球气候变暖的背景下,本文分析了蒙新地区40个气象台站的气温、降雨量和蒸发量数据,可知:近40年来,蒙新地区气温持续上升;2000年之前,内蒙古的降雨量呈增加的趋势,2000年之后骤减,而新疆大部分地区的降雨量呈增加的趋势;蒙新地区蒸发量整体呈现减少的趋势。湖泊的动态变化基本上与气候的变化趋势相吻合。最后,笔者以新疆博斯腾湖为例,分析了湖泊变化的影响因素:气候环境和人类活动。

关键词：内蒙古新疆湖泊遥感气候