我国典型季风海洋性冰川区雪坑中 主要阴、阳离子的来源   总被引：11，自引：0，他引：11  

李宗省  何元庆  庞洪喜  杨小梅  贾文雄  和献中  王旭峰  院玲玲  宁宝英  宋波  张宁宁 《地理学报》2007,62(9):992-1001

运用海盐示踪法、相关分析、趋势分析等方法,对我国两处典型季风海洋性冰川(海 螺沟1 号冰川和白水1 号冰川) 积累区雪坑主要化学离子来源进行了综合分析,结果表明： 两冰川区除Na⁺ 是海洋源外,其他离子主要是非海洋源;Cl^-、NO₃ ^-、SO₄ ^2- 、K⁺、Ca²⁺、Mg²⁺ 非 海洋源所占的比重,在海螺沟1 号冰川依次为52%、99%、100%、98%、99.9%、83%,白水 1 号冰川依次为68%、99%、100%、98%、99%、59%;分析认为,海螺沟1 号冰川离子的非 海洋源主要是大气环流远源物质和高原面物质输入,而白水1 号冰川除上述来源外,冰川区 近源物质输入对离子浓度贡献很大。两冰川区各离子具体来源存在较大的差异性并且阴、阳 离子来源的共源性较低,其主要原因是：(1) 冰川区内局地环境的差异,比如岩性、山谷风系 统、地形地貌等;(2) 两冰川区离子淋溶作用强度的差异,分析认为,海螺沟1 号冰川离子淋 溶作用较强;(3) 不同离子的来源方式、沉降方式、自身化学特征以及沉积后过程不同所致。  相似文献   

陶瓷釉的矿物学特征研究   总被引：2，自引：0，他引：2  

龚国洪  唐荣炳  尹祚莹 《高校地质学报》2000,6(2):327-332

应用原子吸收光谱（AAS）,X射线衍射（XRD）和 电子自旋共振（ESR）方法对工业及民用陶瓷釉进行了研究。实验表明：陶瓷釉的主要化学 成分为Al2O3、SiO2,少量为K2O、Na2O、MgO、CaO和微量的TiO2、Fe2O3 、S等;矿物相有石英、伊利石、方解石、长石、高岭石和滑石等。生釉经不同温度焙烧后 ,无论是化学成分、矿物相、微量杂质元素的价态及含量均发生了变化。讨论了在不同温度下的化学组分、含量、生成矿物相的种类以及杂质离子在矿物内部的电荷转移状态。这些结果对改进陶瓷釉的配方,探索最佳焙烧温度,生产高质量的陶瓷产品,有着实际的指导意义 。  相似文献   

高温高压下流体中电解质活度系数的确定     

苏根利  谢鸿森  李和平  郭捷  丁东业 《矿物岩石地球化学通报》2000,19(1):25-29

高温高压下流体中电解质的活度系数在地球化学领域有着广泛的应用。本实验测量了100—500℃、0．11—12GPa下0．01mol／L KCl溶液的电导率,并利用Hueckel方程由实验确定的摩尔电导和极限摩尔电导计算出了KCl的平均摩尔活度系数。平均摩尔活度系数随温度升高而减小,随压力升高而增大,而在高温高压下随温度压力的升高几乎保持恒定。  相似文献   

钾长石粉酸浸除铁废液资源化的实验研究   总被引：3，自引：0，他引：3  

郑骥马鸿文  章西焕文智慧 《地球科学》2004,29(1):59-64

钾长石粉经过硫酸或盐酸酸浸除铁后, 废液中含有大量的金属离子和游离酸.对废硫酸进行循环利用实验, 钾长石粉铁的浸出率达到88.3%.对酸浸废液进行蒸发结晶, 分别制备得到了纯度为94.1%的绿钾铁矾和74%的三氯化铁.用硫酸酸浸废液蒸发结晶后, 铁的回收率为70.0%, 钾的回收率为96.5%, 整个工艺无需高温, 无需加压, 操作简单, 具有高效、低能耗、低污染的特点, 表明用本项技术处理酸浸废液行之有效.分析认为, 废液呈强酸性、溶液中存在大量Fe2+、碱金属离子含量偏低是蒸发结晶过程中形成绿钾铁矾而不是黄钾铁矾的主要原因.   相似文献   

磁场偶极化过程中磁尾的电离层离子加速:Ⅰ离子分布函数的演化   总被引：2，自引：2，他引：0       下载免费PDF全文

史建魁  刘振兴 《地球物理学报》2000,43(1):11-18

采用动力学方程,对亚暴期间磁尾磁场向偶极形弛豫过程中离子分布函数的演化进行了模拟研究,主要结果为：（１）初始时刻分布函数为相对于速度呈指数下降的离子束,在随时间变化过程中,逐渐变为相对于速度（包括平行和垂直速度）的单峰结构,且单峰在速度空间的位置随时间的变化而向高速方向移动;（２）在速度空间中平行于磁场方向上单峰向高速方向移动得较慢,在垂直方向上移动得较快;（３）轻离子分布函数峰值的位置较重离子随时间的变化向高速方向移动较快。（４）初始能量较高时,离子分布函数的单峰位置向高速方向移动较快。（５）离子团在磁场偶极化过程中表现为一束地向流．本文还对上行离子受感应电场的加速进行了讨论．  相似文献   

Lead and Aroclor 1254 disrupt reproductive neuroendocrine function in Atlantic croaker     

I. A. Khan  P. Thomas 《Marine environmental research》2000,50(1-5):119-123

We have previously shown that lead (lead chloride) and a polychlorinated biphenyl (PCB) mixture (Aroclor 1254) can alter hypothalamic serotonin (5-hydroxytryptamine, 5-HT) content, and pituitary gonadotropin II (GTH II) release in vitro, in the Atlantic croaker (Micropogonias undulatus). In the present study we investigated whether impairment of the hypothalamic 5-HT pathway involves alterations in tryptophan hydroxylase (TPH), the rate-limiting enzyme in 5-HT biosynthesis, or monoamine oxidase (MAO), the catabolic enzyme. Aroclor 1254 (1 mg/kg body wt. for 30 days) significantly inhibited hypothalamic TPH activity without altering MAO activity, and caused a significant decline in 5-HT content. On the other hand, lead exposure (15 mg/kg body wt. for 30 days) only induced a slight decrease in hypothalamic 5-HT content and TPH activity, and a minor increase in MAO activity. However, both Aroclor 1254 and lead significantly inhibited the GTH II response to stimulation by a luteinizing hormone-releasing hormone analog (LHRHa) in vivo and caused reduced gonadal growth. These results demonstrate that impairment of hypothalamic serotonin metabolism by Aroclor 1254 involves inhibition of 5-HT synthesis, whereas lead does not exert a profound influence on 5-HT metabolism. The decline in 5-HT availability due to reduced 5-HT synthesis in the PCB-exposed fish may result in disruption of the stimulatory 5-HT-GnRH pathway controlling GTH II secretion leading to impairment of gonadal growth.  相似文献   

短脉冲激光在实验室天体物理方面的研究进展     

孙嘉宁  袁大伟  王菲鹿 《天文研究与技术》2021,(2):248-254

随着啁啾脉冲放大技术(Chirped Pulse Amplification,CPA)的飞速发展,激光功率密度实现了飞跃式的提升,利用短脉冲激光开展实验室天体物理研究的条件日趋成熟。短脉冲激光与靶相互作用可以产生相对论粒子(正负电子、质子、中子等)和高能电磁辐射(X射线、γ射线),这些粒子和辐射的产生过程与天体中的某些物理现象相对应。介绍了利用短脉冲激光开展实验室天体物理的研究进展,重点介绍了核天体物理、空心离子光谱学、相对论无碰撞冲击波以及等离子体状态诊断等。  相似文献   

Microstructure of NH4Cl-NH3-H2O system studied by ATR-FTIR, Raman and MD simulation          下载免费PDF全文

李非  郭小甫  魏华春  袁俊生 《盐湖研究》2019,27(1)

The solubilities of ammonium chloride in aqueous ammonia decreased first and then increased with increasing ammonia concentrations, but the mechanism of this phenomenon has not been clarified. In the present work, the ATR-FTIR and Raman spectroscopy were employed to investigate the corresponding mechanism. The spectra analysis was focused on the region between 2500 and 4000 cm-1. It was firstly discovered that the N-H???N hydrogen bonds between ammonium ions and ammonia molecule was mainly formed in the NH4Cl-NH3-H2O system with concentrations higher than 10% ammonia, but N-H???O hydrogen bonds between ammonium ions and water molecule took advantage in the system with lower ammonia concentrations. Correspondingly, the phenomena of hydrogen bonding redshift and blueshift was observed respectively compared in NH3?H2O solution. Moreover, the hydrogen bonding structure of the saturated solution was obtained by means of MD simulation. The present work provides some theoretical basis for the separation of ammonium potassium chloride.  相似文献   

Modelling of chloride ingress into concrete through a single‐ion approach. Application to an idealized surface crack pattern     

Santiago Guzmán  Jaime C. Gálvez  José M. Sancho 《国际地质力学数值与分析法杂志》2014,38(16):1683-1706

The paper examines ion (chloride) transport equations in porous media (concrete) integrated over a representative elementary volume, that is to say, averaging over the macroscopic level the phenomena that occur really at the pore scale. There are three basic variables to be used: chloride concentration, moisture and temperature. The diffusion process is examined, in addition to other phenomena such as convection (the motion of dissolved substances caused by flow of water in a pore solution of partially saturated media) or chloride binding (the capacity of free chloride of being chemically bound, particularly with C₃A to form Friedel salts). Contrary to other approaches, such effects are not considered by means of apparent diffusion coefficients but by developing the complete set of time‐dependent equations for both the chloride concentration within the pore solution and the moisture content within the pore space. Once the general model is described, the system of equations can be solved numerically by means of a two‐dimensional finite element formulation. The main objective is to reproduce results of experimental tests by means of a priori parameter estimation, according to the characteristics of materials and external environment conditions, thereby superseding the well‐known best fit a posteriori through Fick's second equation. While the introduction of hygrometric conditions and convection phenomena appears to be of high significance, other factors like temperature, surface concentration, chloride binding or equivalent hydration time are analysed too. The proposed model can reproduce bidimensional complex geometries, for example, cracked concrete cover, as well as variable surface condition. An application case is developed through a realistic model of the geometry of a crack. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

吉林省夹皮沟—金城洞绿岩区中金矿床形成的物理化学条件     

刘劲鸿 《国土资源》1991,(3)

作者应用气液包裹体研究和热力学方法讨论了吉林省夹皮沟—金城洞绿岩区中金矿床形成的物理化学条件,分别确定了Ⅰ矿田(石(?)沟旷田)、Ⅱ矿田(夹皮沟矿田)和Ⅲ矿田(金城洞矿田)的成矿T、P、pH、Eh、fs_2、fo_2、fco_2及成矿溶液性质、成分类型、主要成矿离子Pb~(2+)、Zn~(2+)、Fe~(2+)、[AuS_3]~(3-)的浓度。  相似文献