纤蛇纹石纳米管的水热合成与表征   总被引：3，自引：2，他引：3  

马国华  彭同江  段涛 《矿物岩石》2007,27(1):40-45

采用水热法进行了纤维蛇纹石的合成研究,通过改变反应温度、反应体系pH值合成了多个样品,并利用X射线衍射仪、透射电子显微镜、扫描电子显微镜和红外光谱仪等手段对合成样品的物相、结构和形貌进行表征,分析表明在180℃～220℃、pH值为10.39～13的水热体系中均能够合成纤蛇纹石结构纤维;在220℃、pH值为13的条件下合成晶型最好、纤维最长的纤蛇纹石纳米管,其内径约6 nm～8 nm、外径约30 nm～35nm,长约200 nm～400 nm。  相似文献   

非金属矿物的改型改性及其在环境保护中的应用   总被引：1，自引：0，他引：1  

潘忠华  潘兆橹 《地质科技情报》1995,14(3):51-55

沸石、粘土矿物及石棉都是重要的非金属矿物。通过物理的和化学的改型改性，可以明显地提高沸石及粘土矿物的离子交换性、吸附性及催化性等，可用作环境中无机和有机毒物的离子交换剂、吸附剂或燃烧催化剂。对石棉的表面改性则可以抑制或改变石棉的有害生理活性，减少石棉生产以人体及环境的危害。  相似文献   

基于多次非暴露式气管滴注的染毒法研究温石棉致大鼠肺损伤的作用          下载免费PDF全文

柏珺  崔琰  张青碧  霍婷婷  查雨欣  邓建军 《岩石矿物学杂志》2017,36(6):916-924

温石棉是一种安全性存在争议的石棉,合理可行并且能够真实反映其暴露致病过程的染毒方法对深入研究其致病机理有着重要意义。本文采用多次非暴露式气管滴注的染毒方法对雄性Wistar大鼠分别进行不同浓度温石棉悬液的染毒,在染毒1、3和6个月后记录体重和肺脏器系数,观察肺组织大体及苏木素-伊红(HE)染色的病理形态,对支气管肺泡灌洗液(BALF)中白细胞总数进行分类计数,并测定总蛋白(TP)、乳酸脱氢酶(LDH)、酸性磷酸酶(ACP)和碱性磷酸酶(AKP)的含量。结果表明,多次滴注的方式大鼠死亡率较低,并且每次滴注后能够苏醒的大鼠没有死亡发生;随着四川新康温石棉染毒时间的延长和染毒剂量增加,大鼠体重增长缓慢,肺脏器系数升高,肺大体出现水肿、肉芽肿、萎缩实质化,HE染色观察则表现为炎性细胞增多、肺泡结构遭到破坏以及出现纤维化;随着染毒时间的延长,支气管肺泡灌洗液(BALF)中的白细胞总数、中性粒细胞和淋巴细胞百分比呈上升趋势,巨噬细胞百分比呈下降趋势,TP、LDH、ACP和AKP均表现为上升的趋势,并呈现一定的剂量-效应关系。综上所述,多次非暴露式气管滴注方法可用于模拟温石棉慢性暴露的致病过程,四川新康温石棉可以通过破坏巨噬细胞、肺泡上皮细胞及肺泡上皮-毛细血管屏障造成大鼠的肺损伤。  相似文献   

硫酸氢铵与石棉尾矿混合焙烧浸取MgO过程分析     

孙红娟  宋鹏程  彭同江  谭道永  张海阳 《岩石矿物学杂志》2015,34(6):853-859

主要化学成分是SiO2和MgO的石棉尾矿与作为化学助剂的硫酸氢铵混合焙烧后可提取MgO并分离出活性SiO2残渣。本文研究了这一焙烧过程中主要金属氧化物的浸取率(以MgO表征)、焙烧产物水浸残渣剩余量及其与物相组成之间的相互关系,获得了优化的混合焙烧工艺参数,并结合焙烧水浸产物的物相变化,分析了焙烧过程中矿物和生成物的变化。结果表明,在NH4HSO4/MgO(摩尔比)为4、焙烧温度为500℃、焙烧时间为2 h、尾矿粒度为120目的条件下,石棉尾矿中的矿物分解最为彻底,MgO提取率最高;焙烧过程中,水镁石、方解石和富铬斜绿泥石反应活性高,蛇纹石次之,滑石最差;石棉尾矿中的金属氧化物与硫酸氢铵反应形成可溶硫酸盐,而硅氧四面体骨架转变成无定形活性SiO2残骸。研究结果对石棉尾矿的资源化利用和环境保护具有重要意义。  相似文献   

The sequence of geological events and the dynamics of the Milky Way galaxy     

Johann Steiner 《Australian Journal of Earth Sciences》2013,60(1):99-131

Present‐day galactic data permit the construction of a galactic model in which the galactic gravitational field is described by a gravitational function rather than the Newtonian gravitational “constant” G. The concept of this empirical gravitational function, which is based on galactic orbital velocity data, envisages G as a function of time and space. In this model the interaction of this gravitational function, which has rotational symmetry in the galactic plane, and the slightly elliptical galactic orbit of the solar system results in a systematic variation of G. This interaction specifies a simple galactic time‐scale which can be conveniently compared with events of the geological time‐scale. For reasons of galactic evolution and modifying effects due to suspected changes of mass distributions in the universe with the passage of time, which are classed here under the Dirac‐Jordan Effect, such a comparison is initially restricted to the past 1#fr1/4> cosmic years, or 350 million years. The problems in extending such a comparison to 8 cosmic years are discussed, and such an extension seems promising, but it is hampered by the paucity of geological and geophysical data from the lower Palaeozoic and the Precambrian and the present uncertainties in regard to galactic evolution.

“Worldwide” statistical maxima and minima of the following geological criteria disclose an episodic correlation with the variation of G and the rates of change of G during the past 350 million years, as specified by this galactic model. It is possible to interpret this correlation in terms of accepted geological principles and concepts in most cases. The following geological phenomena are considered in this comparison of the galactic and geological time‐scales for the past 350 million years.