49 research outputs found
The biotoxic effect of ZnO nanoparticles on three zooplankton
纳米氧化锌(ZnO-NPs)因其特殊的理化性质而在化妆品、医学抗菌、工业涂料等领域被广泛应用。其通过工业生产、商品使用、空气沉降、运输泄露、地表水径流等途径直接或间接汇入海洋环境,对海洋的生态系统构成潜在威胁。海洋中的浮游动物可以通过摄食影响或控制初级生产力,同时它们的种群动态变化又影响许多鱼类和其他动物资源群体的生物量。开展纳米氧化锌对浮游动物的毒性效应研究,对于了解纳米材料在水体中行为、评价浮游动物对纳米材料的响应、实现纳米材料环境危害性的合理评估具有十分重要的意义。 本研究选取了典型模式种日本虎斑猛水蚤、广泛分布的安氏伪镖水蚤和枝角类代表蒙古裸腹溞这三种浮游动物进行混合培养,分析ZnO...Zinc oxide nanoparticles is widely used in cosmetics, medical antibacterial, industrial coatings and other fields because of its special physical and chemical properties. It is directly or indirectly imported into the marine environment through industrial production, commodity used, air sedimentation, transport leakage, surface runoff, posing a potential threat to marine ecosystems. The zooplankto...学位:理学硕士院系专业:海洋与地球学院_海洋生物学学号:2232014115136
Investigation of lithium manganese oxides with large tunnel structure as electrode material in Li ion batteries
锂锰氧化物材料是一类重要的锂离子电池电极材料。文中报道一种新型大隧道结构镁锰复合氧化物〔结构类型:钡镁锰矿(TOdOrOkITE)型〕的合成方法及其电化学性能表征。X-光衍射(Xrd)谱证实了合成物具有所预想的(3x3)隧道结构。在慢速循环伏安图中可发现该类电极材料分别在3.35V及2.45V(VS.lI)出现一对锂离子的脱出-嵌入峰。充放电实验结果表明:该类大隧道结构复合氧化物可作为一种3V锂离子电池的电极材料,当充放电电流密度为0.1MA/CM2时,材料的初次容量可达158MAg/H,经过4次充放电循环后其容量仍可保持在约130MAH/g。Lithium manganese oxide is one kind of the important electrode material of Li ion batteries.In this paper, investigations of a novel Li Mn oxide electrode material with large tunnel structure such as todorokite type electode material For Li ion batteries are carried out in the lab.It is demonstrated that the material synthesized has a todo rokite structure (i.e.3×3 tunnel)using X ray diFFraction(XRD) method.It is also observed that a couple of deintercalation/intercalation peaks of lithium ion appear at 3.35V and 2.46V (vs.Li) respectively in the slow rate cyclic voltammograms.In addition,it is Found that the material shows quite good cyclic perFormance,the initial capacity of the material is 158mAh/g,and its discharge capacity is still kept at about 130mAh/g aFter Four cycles at charging/discharging current density of 0.1mA/cm 2.福建省自然科学基金;杰出青年基
一种固液发动机药柱及其制备方法
本发明公开了一种固液发动机药柱及其制备方法,通过单位螺旋二十四面体极小曲面结构沿三维进行阵列至大于药柱的尺寸,得到螺旋二十四面体晶格结构;进行加厚,获得片层状螺旋二十四面体晶格结构;将药柱模型与片层状螺旋二十四面体晶格结构相交,得到与药柱模型一致的螺旋二十四面体晶格结构;3D打印后得到药柱的金属燃料架构,在金属燃料架构的孔隙中填充固体燃料,固化成型为药柱。本发明通过使用金属材质极小曲面结构嵌入固体药柱的方法,实现了金属燃料的均匀添加,提高了药柱的密度比冲,不会对发动机其他部件、结构有任何负担性影响,解决了现有技术中金属粉末难以在固体燃料中分布均匀的问题
