锌精矿常压浸出与加压浸出工艺比较

比较了常压浸出与加压浸出两种工艺的机理、流程、技术经济指标、投资以及存在的问题。试验和生产数据表明,加压浸出在技术上和工艺上都更具有吸引力。     

低品位氧化锌粉矿制粒及碱性浸出

小于2 mm的氧化锌矿(含锌5.17%)与5%的水泥混合,制粒并固化,所得颗粒直径5~8 mm。固化3天、10天、45天的颗粒用碱性溶液浸出,最大浸出率分别为92.2%、87.3%、72.9%。减少固化时间能够缩短反应时间、增加颗粒中锌的溶解以及减少浸出剂中初始锌浓度的影响。实验表明颗粒最少需固化3天。动力学研究表明浸出过程受浸出剂通过脉石层的扩散控制,表观速率常数分别为3.51×10-2d-1、8.09×10-3d-1和4.74×10-3d-1。     

中温SOFC密封玻璃热稳定性研究

研究了一种热稳定性好的中温固体氧化物燃料电池密封玻璃. 研究表明, 此密封玻璃的热膨胀系数(室温～631℃)为9.8×10^-6/K, 与8YSZ电解质的热膨胀系数10.0×10^-6/K(室温～631℃)接近, 并且在700℃热处理300h后, 该密封玻璃的热膨胀系数几乎没有变化. 粘度实验表明, 玻璃在700℃下具有足够的刚性, 适合于运行温度在700℃左右SOFC的密封. 化学相容性的研究显示, 在700℃下与8YSZ反应300h后没有发现显著的界面反应.     

Uniformity of gallium doped zinc oxide thin film prepared by pulsed laser deposition

Recently, transparent conducting oxide thin films have attracted attention for the application to transparent conducting electrodes. In this work, we evaluated the uniformity of electrical, optical and structural properties for gallium doped zinc oxide thin films prepared on the 10 × 10 cm² silica glass substrate by pulsed laser deposition. The resistivity, carrier concentration, mobility, bonding state and atomic composition of the film were uniform along in-plane and depth direction over the 10 × 10 cm² area of the substrate. The film showed the average transmittance of 81-87%, resistivity of 1.4 × 10^− 3 Ω cm, carrier concentration of 9.7 × 10²⁰/cm³ and mobility of 5 cm²/Vs in spite of the amorphous X-ray diffraction pattern. The gradual thickness distribution was found, however, the potential for large-area and low temperature deposition of transparent conducting oxide thin film using pulsed laser deposition method was confirmed.     

添加物对Fe_2O_3超微粒的稳定作用

粒子的尺寸直接关系着气敏元件性能的好坏．为了防止Ｆｅ２Ｏ３超微粒在气敏元件烧结过程中长大，我们在纯Ｆｅ２Ｏ３中掺入５ｍｏｌ％碱土金属离子，利用ＸＲＤ和ＴＥＭ系统研究了掺杂物对Ｆｅ２Ｏ３超微粒子的稳定作用，并对由掺杂引起的Ｆｅ２Ｏ３电学性质的变化作了初步探讨．     

Correlation between structural and optical properties of 30 nm and 60 nm lead sulfide nanowires

PbS nanowires with 30 nm and 60 nm diameter fabricated under the same condition of electrochemical deposition with sulfuric and oxalic anodic alumina membranes (AAM), respectively, have been successfully prepared in order to study their optical properties in relation to their size. Scanning electron microscopy indicates that the 60 nm PbS nanowire arrays have the same shape with the 30 nm. X-ray diffraction result shows that 60 nm PbS nanowires are crystalline and have a highly (200) preferential orientation like 30 nm ones. UV spectrum considers the nanowire size decrease as the absorption peak shifts to the blue. The quantum confinement effects compared between 30 nm and 60 nm PbS nanowire arrays were observed by the measurements of ultraviolet-visible absorption spectroscopy (UV-vis).     

氧化钇纳米粉体材料的制备

以YCl3为原料 ,以Na2 CO3为添加剂 ,聚乙二醇 4 0 0为分散剂 ,首先制备出晶粒细小的碳酸钇前驱体。在 70 0℃焙烧 1h后制得Y2 O3纳米粉体材料 ,经XRD和TEM检测 ,粒径为 5 0nm ,粒度均匀     

Pulsed Electromagnetic Field (PEMF) Treatment Reduces Lipopolysaccharide-Induced Septic Shock in Mice

Despite advances in medicine, mortality due to sepsis has not decreased. Pulsed electromagnetic field (PEMF) therapy is emerging as an alternative treatment in many inflammation-related diseases. However, there are few studies on the application of PEMF therapy to sepsis. In the current study, we examined the effect of PEMF therapy on a mouse model of lipopolysaccharide (LPS)-induced septic shock. Mice injected with LPS and treated with PEMF showed higher survival rates compared with the LPS group. The increased survival was correlated with decreased levels of pro-inflammatory cytokine mRNA expression and lower serum nitric oxide levels and nitric oxide synthase 2 mRNA expression in the liver compared with the LPS group. In the PEMF + LPS group, there was less organ damage in the liver, lungs, spleen, and kidneys compared to the LPS group. To identify potential gene targets of PEMF treatment, microarray analysis was performed, and the results showed that 136 genes were up-regulated, and 267 genes were down-regulated in the PEMF + LPS group compared to the LPS group. These results suggest that PEMF treatment can dramatically decrease septic shock through the reduction of pro-inflammatory cytokine gene expression. In a clinical setting, PEMF may provide a beneficial effect for patients with bacteria-induced sepsis and reduce septic shock-induced mortality.