Ce掺杂羟基铁插层蒙脱石的光催化性能研究

使用离子交换的方式制备了掺杂Ce的羟基铁插层蒙脱石,通过X射线粉末衍射分析(XRD)、红外光谱(FTIR)、X射线电子能谱(XPS)以及BET比表面积分析等测试手段对催化剂进行了表征。在不同实验条件下,使用插层蒙脱石作为异相光助Fenton试剂,考查了催化剂在紫外光条件下降解活性艳蓝的光催化性能。实验结果表明,掺杂Ce能明显提高羟基铁插层蒙脱石的光催化效率。在活性艳蓝(KN-R)初始质量浓度ρ0(KN-R)=75mg/L,pH=3.0,H2O2初始浓度[H2O2]0=4.9mmol/L条件下,t=100min时,掺杂2%Ce的铁插层蒙脱石对活性艳蓝的降解率为99.5%。实验结果结合化学结构的分析表征探讨了Ce对催化效果的影响。     

REE Geochemistry of Loess in Xinjiang ,China

The total rare-earth element values(ΣREE)of loess in the Xinjiang region vary over a range of 128-200 ppm ,with an average of 153ppm .The average REE content of loess lies between the earth‘s crust (155ppm) and sedimentary rocks(151ppm).The Xinjiang loess,with the REE distribu-tion patterns characterized by negative slopes ,is rich in the Ce-family elements, and has a distribu-tion pattern characteristic of sedimentary rocks.The North Xinjiang loess is relatively depleted in Tb,but rich in Yb and Lu.The South Xinjiang loess is relatively rich in light rare-earth elements.This is full proof that the Xinjiang loess comes partly from weathered materials(clay rock,sandstone)in the region studied.The REE distribution patterns in the Xinjiang loess are similar to those in the precipitated dust and Aeolian sand,indicating the same material source.The REE distribution pat-terns in the Xinjiang loess are also similar to those in loess from the middle Yellow River Valley,China and Taskent,the former USSR.This implies that loesses of the three locations(Xinjiang,the mid-dle Yellow River Valley and Taskent) come from a common material source.But the REE patterns in the Xinjiang loess are different from those in wall rocks (volcanic rock,K-bearing volcanic rock).Generally ,LREE/HREE,Eu/Eu* and Ce/Ce* ratios reflect the features of parent materials of loess,indicating that the parent rocks were probably in the early stage of alkaline weathering and the weathered materials existed in an oxidation environment with basic mediums under arid-climatic conditions before transport.As a result,the migration ability of the REE is weak.     

江西大吉山五里亭花岗岩中变生褐帘石的加热研究

对采自我国南方燕山期五里亭花岗岩体中的褐帘石,经偏光显徽镜、电子探针仪、差热仪、X射线等方法进行分析得出,该矿物为变生褐帘石。加热800℃,850℃,950℃,970℃,1100℃退火系列样品的X射线粉晶数据分析得出:1.变生褐帘石X射线粉晶分析的最宜加热温度为800-850℃;2.加热至970℃的退火样品,褐帘石已分解为方铈石、赤铁矿、钙长石,加热到1100℃,褐帘石已渐消失,方铈石、钙长石和赤铁矿成为主要矿物相。     

粤西新榕锰矿成矿物质来源的Ce，Nd同位素证据

首次测定了粤西新生代迁积型新榕锰矿床中的矿石与岩石以及扬子地台南缘若干碳酸盐型锰矿石样品的Nd,Ce同位素组成,由此推断新榕锰矿床的成矿物质来源于该地区已遭受剥蚀或被构破坏的中泥盆世后晚古生代含锰碳酸盐地层。     

氟碳钙铈矿晶体结构解析探索

氟碳钙铈矿从１８３５年发现至今已有一百五十多年的历史。然而迄今还没有人深度用结构因子计算法成功测定其晶体结构，只有推测结构模型与部分原子位，本文第一次用结构因子计算法完成该矿物二级亚晶胞ａ＇ｃ＇的结构测定。晶体简易化学式Ｃｅ２ＣａＦ２［ＣＯ３］３，ａ＇ｃ＇亚晶胞空间群为Ｐ６３２２，晶胞参数ａ＇＝ｂ＇＝０．４１０１ｎｍ（ａ＝０．７１０４（１）ｎｍ，ａ＇＝１／√３ａ），ｃ＇＝２．７９０１（４）ｎｍ，ｒ     

层硅铈钛矿的矿物学研究

层硅铈钛矿是一种罕见又多变的矿物,因而至今未见详细报导。笔者在赛马碱性岩体的铀、钍、铌、稀土巨型综合矿床中获得了各种成因的新鲜矿样,作了系统的研究,指出该矿物为单斜晶系、具类似2M型白云母结构的层状钛硅酸盐。