防辐射有机玻璃板材的抗辐射性能

系统研究了含铅有机玻璃、含钡有机玻璃、含硼有机玻璃和普通有机玻璃的ｘ、γ射线和中子射线防护性能及其耐６０Ｃγ射线辐照稳定性。结果表明，含铅有机玻璃板材具有良好的ｘ射线、反应堆热柱γ射线屏蔽性能；合硼有机玻璃板材具有良好的热中子屏蔽性能；含钡有机玻璃板材的褪化裂变谱中子辐射屏蔽性能良好；含钡有机玻璃和普通有机玻璃可耐１０５～１０６Ｇｙ的６０Ｃｏｙ射线辐照；含铅有机玻璃板材耐６０Ｃｏｙ射线照射能力小于１０５Ｇｙ。     

腈氯纶吸附纤维对亚甲基蓝和铅离子的共吸附行为研究

采用无机活性炭与丙烯腈-偏氯乙烯共聚体共混,以二甲基甲酰胺为溶剂纺制了腈氯纶吸附纤维,并用水合肼控制预交联过程,通过碱性水解制得羧酸钠型离子交换吸附纤维,着重考察了该纤维在染料亚甲基蓝和重金属Pb2 混合共存条件下对2种物质的共吸附行为.结果表明,混合条件下,该纤维对亚甲基蓝和Pb2 的吸附量可分别达到9.5 mg·g-1和487.8 mg·g-1;活性炭对亚甲基蓝的物理吸附与改性纤维对Pb2 的离子交换过程同时发生,离子交换的发生对物理吸附的影响较大;Langmuir模式比Freundlich模式更适于描述Pb2 的等温吸附过程;随着温度的升高,纤维的物理吸附能力增强,而对Pb2 的离子交换性能变化不大;pH为中性条件时,纤维对Pb2 和亚甲基蓝的吸附量均达到最大.     

Plants emit sulfate-, phosphate- and metal-containing nanoparticles

Environmental Chemistry Letters - The presence of engineered and natural nanoparticles in the atmosphere is of concern for health and climate. Actually there are few studies on the release of...     

多级生物系统工程处理沈阳西部污水的研究(示范工程)

建立以污水驱动水轮机,再带动转盘和低坝的落水曝气充氧,和大气复氧,菌藻吐氧,达到多次充氧的多级生物系统工程,以逐级沉淀和多次降解,以及沙滤等设施代替工厂处理的复杂工程。在沈阳西部中试结果证明该工程结构简单、管理方便、处理效果高、节能节资.同时,建立了快速监测生物活性和水质毒性的方法.     

Discovery of nano-sized gold particles in natural plant tissues

Biological effects of nanoparticles have attracted widespread attention. However, the interaction between plants and nanoparticles remains unclear. The purpose of this study was to investigate characteristics of nano-sized metal particles in two representative plant species, Erigeron canadensis and Boehmeria nivea, in the Guangdong Province, China. The stems of the plants were sliced and placed on Ni–C grids for field-emission transmission electron microscopy (TEM). The metal-bearing nanoparticles were further analysed for their size, shape, composition, content and other characteristics using X-ray energy spectrum analysis, scanning TEM and selected-area electron diffraction pattern. The results revealed that the plants contain nano-sized Au-bearing particles with a diameter of 5–50 nm, ellipsoid, spherical and bone-rod shapes or irregular morphology with smooth edges. These nanoparticles primarily consisted of Au, Cu, O and Cl. The discovery of Au-bearing nanoparticles in natural plant tissues is of great significance for biological nanoscience. Here, we discuss the function and absorption mechanism of Au-bearing nanoparticles in plants and present the influence of the discovery of Au-bearing nanoparticles in natural plants.