多种超细矿物颗粒在模拟人体体液中溶解行为研究

发布时间：2018-06-10 04:07

本文选题：矿物粉尘 + PM2.5　；参考：《西南科技大学》2015年硕士论文

【摘要】：随着经济和社会的飞速发展,大气污染也作为发展的代价日益严重,并严重影响着人类的生活和工作环境,对人体健康造成巨大危害。雾霾天气的频发更是让人们意识到了大气颗粒物污染的严重性。大气颗粒物可通过呼吸系统和消化系统进入人体,进而对人体造成伤害。本论文以矿物粉尘(石英、方解石、纳米Si O2、纳米Ca CO3)及自然降尘为研究对象,对其在不同模拟人体体液中的溶解特性进行研究。利用XRD、SEM及ICP等手段对反应后固体的物相、形貌和滤液中的溶出元素进行分析,此外,以石英和方解石为主要研究对像,分别探讨了石英和方解石在模拟人体体液中的元素溶出情况,同时对西宁降尘在模拟人体体液中溶解前后的表面形貌、物相及元素溶出进行了实验研究,以更好的理解矿物粉体被人体吸入后在人体体液内的溶解行为。结合处理前后矿物特性的变化,探讨大气颗粒物与人体的作用机理。几种矿粉溶解在不同的模拟人体体液中,混合悬液的p H在反应初期变化最快,一般在初始4h的溶解过程中反应液p H值变化最快。反应1d后溶液p H值变化不大,基本趋于稳定,第6d至8d溶液酸度微略增加。在不同的矿粉/模拟人体体液体系中,作用8d后,溶液的p H基本都稳定在8~8.5之间,缓和液偏碱性。较其他矿粉,纳米Si O2所在的几种不同溶液的p H值较低,方解石和纳米Ca CO3溶解过程中,溶液p H变化十分相似。SEM结果显示,矿粉在模拟人体体液中作用8d后,表面和边壁均出现了不同程度的凹蚀、表面剥离现象。溶解主要发生在矿物的表面和边壁,并仍有大面积未被腐蚀的区域,且占主要部分。多数矿物颗粒溶解后边缘更加光滑,部分颗粒边缘锯齿现象较明显。经反应液流体的不断碰撞、溶蚀,出现了更多的细小颗粒,大部分块状石英颗粒反应后厚度减薄,并且呈现出层层解理的溶解趋势,大大加大了矿物粉体与溶液的接触面积。矿粉自身的结构对溶解起到决定性的作用,一般条件下,碳酸盐矿物较硅酸盐矿物易于溶解。溶液的酸度对矿物溶解存在很大的影响,酸性条件一般可促进方解石及纳米Ca CO3的溶解而对石英及纳米Si O2存在一定程度的溶解抑制,这和前人的研究结果一致。在降尘的溶解过程中,方解石很快的与模拟人体体液反应并溶解,而石英、长石、云母的溶解非常缓慢。大气颗粒物与人体接触后,随着颗粒物组分的溶解,接触溶液p H迅速升高,而这恰好促进矿物中Si的溶出。因此,当降尘与人体酸环境接触不仅会对接触部位的液体环境造成影响,而且还将促进有毒有害的Si的溶出,进一步加重了大气颗粒物对人体的危害。通过对矿粉溶解前后进行FTIR红外光谱分析,矿粉在溶解前后其红外特征吸收峰并未发生明显变化,即8d的溶解作用并未对矿物表面官能团造成很大的影响。较明显的是,方解石和石英经模拟人体体液作用8d后,可以发现个别特征吸收峰的峰位发生一定的波数移动,吸收峰的相对峰强发生一定程度的改变。石英红外吸收光谱中特征峰峰位有一定的偏移,相对峰强变化较明显,但总体而言溶解对石英表面官能团无显著影响。由于石英、纳米Si O2、方解石及纳米Ca CO3结构的稳定性,作用8d后矿粉并没有新的物相生成。矿粉表面官能团及物相并未发生明显变化,溶解并未引起整个颗粒晶体结构的崩塌,颗粒结构保持完整。可见在模拟人体体液环境下,矿粉的溶解发生在表层,溶解是十分缓慢的过程。
[Abstract]:With the rapid development of economy and society, air pollution has become more and more serious as the cost of development, seriously affecting human life and working environment, causing great harm to human health. The frequent haze weather makes people realize the severity of atmospheric particulate matter pollution. Atmospheric particulate matter can be passed through the respiratory system and digestive system. In this paper, the dissolution characteristics of mineral dusts (quartz, calcite, nano Si O2, nano Ca CO3) and natural dust are studied in this paper. The dissolution characteristics of the body fluids in different simulated human body are studied. The phase, morphology and dissolved elements in the filtrate are introduced by means of XRD, SEM and ICP. In addition, the element dissolution of quartz and calcite in human body fluid was discussed with quartz and calcite as the main research image. The surface morphology, phase and dissolution of the dust in the simulated body fluid before and after the dissolving of the body fluid in Xining were studied to better understand the mineral powder being absorbed by the human body. The dissolution behavior in body fluid and the changes in the mineral properties before and after treatment are combined to explore the mechanism of the action of atmospheric particles and the human body. Several mineral powders dissolve in different simulated body fluids. The P H of mixed suspension is the fastest in the initial reaction, and the P H value of the reaction solution is the fastest in the initial 4H dissolution process. After the reaction 1D, the reaction is the fastest. The value of P H in solution changed little, basically stabilized, and the acidity of the solution from 6D to 8D increased slightly. In different mineral powder / simulated body fluid system, after 8D, the P H in the solution was basically stable between 8~8.5 and the solution was alkaline. The P H value of several different solutions of the nano Si O2 was lower than that of other mineral powders. Calcite and nano particles dissolved in the solution. During the process, the changes of P H in solution are very similar to.SEM results, and the results show that the surface and side wall of the mineral powder have different degrees of concave erosion and surface dissection after the action of 8D in the body fluid, and the dissolution mainly occurs on the surface and side wall of the mineral, and there is still a large area that is not corroded, and the main part is dissolved, the majority of the mineral particles dissolve after the dissolution. The edge of the particles is more smooth, and the edges of some particles are more obvious. After the continuous collision of the fluid, more fine particles are found. Most of the bulk quartz particles are thinner after the reaction, and the dissolution trend of the layer cleavage is presented. The contact area between the mineral powder and the solution is greatly increased. The structure of the mineral powder itself is dissolved. The solution plays a decisive role. Under general conditions, carbonate minerals are easier to dissolve than silicate minerals. The acidity of the solution has a great influence on the dissolution of minerals. Acid conditions can generally promote the dissolution of calcite and nano Ca CO3 and inhibit the dissolution of quartz and nano Si O2 in a certain degree, which is in agreement with the previous research results. In the process of dissolving the dust, calcite quickly reacts with the simulated body fluid and dissolves, and the dissolution of quartz, feldspar and mica is very slow. After the contact between the body and the body, the P H of the contact solution increases rapidly with the dissolution of the particles, and this just promotes the dissolution of the Si in the mineral. It will not only affect the liquid environment of the contact area, but also promote the dissolution of toxic and harmful Si, and further aggravate the harm of atmospheric particles to the human body. By the FTIR infrared spectrum analysis before and after the dissolution of mineral powder, the absorption peak of the mineral powder before and after dissolution has not changed obviously, that is, the dissolution of 8D and There is no significant effect on the surface functional groups of the mineral. It is obvious that after the calcite and quartz are simulated by the body fluid action of 8D, the peak position of some characteristic absorption peaks can be found to occur a certain number of wave numbers, and the relative peak intensity of the absorption peak is changed to a certain extent. The peak position of the characteristic peak in the absorption spectrum of Shi Yinghong is offset to a certain extent. The relative peak intensity changes obviously, but in general, dissolution has no significant influence on the quartz surface functional groups. Due to the stability of quartz, nano Si O2, calcite and nanoscale Ca CO3 structure, there is no new phase formation after the action of 8D, and there is no obvious change in the functional phase of the surface of the mineral powder. Dissolution does not cause the crystal structure of the whole particle. In the simulated human body fluid environment, the dissolution of mineral powder occurs on the surface, and dissolution is a very slow process.
【学位授予单位】：西南科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X513

【参考文献】