共查询到20条相似文献,搜索用时 93 毫秒
1.
2.
FENG Changgen ZHUO Xiaoxi LIU Xia 《中国稀土学报(英文版)》2009,27(5):717-722
A series of photocatalysts, K11[Ln(PW11O39)2]/PVA (Ln=La, Ce, Pr, Nd, Sm) were prepared by K11[Ln(PW11O39)2] (Ln=La, Ce, Pr,Nd, Sm) containing five kinds of lanthanides and polyvinyl alcohol as the support. The catalysts obtained were characterized by Fourier trans-form infrared spectra, UV-vis spectra, powder X-ray diffraction, and scanning electron microscopy, indicating that the structure of K11[Ln(PW11O39)2] and polyvinyl alcohol remained intact, respectively. The photocatalysts exhibited efficient catalytic activity to degrade methyl orange, Congo Red, Ponceau 2R. The maximal degradation conversions of the three kinds of dyes were 99.58%, 47.61%, 72.42%, respectively. 相似文献
3.
在香港校园里,常常有这么一群特殊的人,她们每天早早地来到学校,为学生测量体温,观摩学校早会,协助管理图书,课余为学生讲故事,中午帮学生盛饭,甚至为学校编辑刊物,放学为低年级学生辅导作业……俨然是学校的正式教师,其实是学生家长,她们为学校,帮老师做了很多事情,都是义务的,没有任何报酬,在香港,通常把她们称之为“家长义工”。 相似文献
4.
5.
业绩略低于预期第三季度公司实现营业收入1471394万元,同比上涨30.67%,净利润91950万元,同比下降26.9%,每股收益0.30元,前三季度实现营业收入4154476万元,同比上涨45.46%,净利润369876万元,同比增长13.76%,每股收益1.22元,业绩略低于市场的普遍预期。 相似文献
6.
7.
提出了用火焰原子吸收光谱法测定金锭中Cu,Ag,Fe,Pb,Bi,Sb的方法。用乙酸乙脂萃取分离金,水相浓缩后测定6种待测元素,方法的检出限:Cu,Ag,Fe为0.021mg/L,Pb,Bi,Sb为0.24mg/L;回收率94%~106%;RSD小于10.6%。该方法快速、简便,样品用量少,测定结果与ICP AES法和国家标准方法一致。 相似文献
8.
9.
10.
型铁中Si,Mn,P,S四大元素的测定是型铁质量评价的主要内容。以往化学法分析Si,Mn,P,S四大元素,劳动强度大,工序繁琐,偶然误差因素多,分析周期长,准确度低。近年来,X射线荧光光谱仪在冶金、地矿、水泥等分析应用方面,得到迅速发展,它具有自动化程度高,操作简单、快速、准确、非破坏性等优点,本文应用3530荧光光谱仪,分析型铁中的Si,Mn,P,S四大元素,取得了成功,方法简单、准确、快速。1实验部分1.1仪器和试剂3530X射线荧光光谱仪(日本理学),Rh靶,端窗X射线管;PR—10气体;… 相似文献
11.
通过对一例国内某冶金企业高炉余压TRT发电机组运行过程中失磁保护动作导致发电机组运行中事故跳闸的分析和说明,从理论和实际上分析了机组跳闸的原因,指出了存在的问题和解决措施。 相似文献
12.
13.
14.
分析了3000kW背压汽发电机因功率方向继电器接线错误引起的频繁误跳闸事故,并指出了保护误动作的原因和改正的方法。 相似文献
15.
16.
邯宝公司高炉TRT励磁系统发生数次故障导致机组跳闸,经查是因高炉炉顶压力陡变时发电机组振动引起励磁回路暂时开路所致。经处理后有效消除了故障原因。 相似文献
17.
因变电站主变故障跳机,造成20000m3/h制氧机组和6000m3/h制氧机组全线停机,在机组启动过程中造成20000m3/h空分主换热器出现过冷现象。文章介绍了为避免过冷现状扩大的事件经过、原因分析、处理措施及预防此类事故的措施。 相似文献
18.
19.
为研究影响城市交通结构的主要因素,建立出行者属性与个体出行方式选择的合理关系模型.所有的出行者相关属性数据均由统计资料获得,方式选择数据由蚌埠市居民出行调查的数据获得.应用非集计模型来建立个人属性、家庭属性和出行属性与方式选择间的函数关系.建模结果表明:居民出行交通方式选择与个人属性、家庭属性和出行属性之间有较稳定的关系,其随着时间的推移变化甚微.非集计模型所推算的交通方式结构较为精确,可用于交通方式结构的预测.此外,所建模型亦能识别方式分担的主要影响因素,从而实现交通方式结构优化. 相似文献
20.
Thirty-four of 54 campers on a 2 week trip in mountains of Utah had diarrhea during and after their trip. Twenty-two (79%) of 28 symptomatic campers' stools examined contained Giardia lamblia cysts, whereas 4 (29%) of 14 asymptomatic campers' stools had cysts. The temporal distribution of cases and the absence of clustering among food preparation subgroups suggested a common source exposure. Although the epidemiologic data and fecal coliform counts implicated the remote mountain stream used as water source by the group as the vehicle of transmission, Giardia lamblia cysts were not recovered from stream water nor were they found in intestines or feces of sampled mammals living in the drainage area. Twenty-five other campers had stools examined before and after a subsequent hiking trip in another area of Utah; none had Giardia cysts before, but 6 (24%) had them after return. Questionnaires returned by 133 of the campers showed that 5% had an illness compatible with giardiasis within 2 weeks after their trip. These surveys show that campers exposed to mountain stream water are at risk of acquiring giardiasis. 相似文献