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991.
中国工业清洗行业发展状况 总被引:1,自引:3,他引:1
较详细、系统地介绍了我国化学清洗技术、物理清洗技术、生物清洗技术的发展历程及应用情况,阐述了我国工业清洗行业的发展状况,指出了我国工业清洗业面临的问题及对策。 相似文献
992.
Yuhao Lu 《Electrochimica acta》2007,52(7):2562-2569
The electrochemical behavior of cobalt phthalocyanine/platinum as methanol-resistant oxygen-reduction electrocatalyst for DMFC was investigated. Platinum was chemically deposited on the carbon-supported cobalt phthalocyanine (CoPc), and then it was heat-treated in high purity nitrogen at 300 °C, 635 °C and 980 °C. In order to evaluate the electrocatalytic behavior of CoPc-Pt/C, the PtCo/C and Pt/C as reference catalysts were employed. TGA, XRD, EDAX, XPS and electrochemical experiments were used to study the thermal stability, crystal structure, physical characterization and electrochemical behavior of these catalysts. These catalysts exhibited similar electrocatalytic activity for oxygen reaction in 0.5 M H2SO4 solution. In methanol tolerance experiments, Pt/C, PtCo/C and CoPc-Pt/C heated at 980 °C were active for the methanol oxidation reaction (MOR). The presence of Co did not improve resistance to methanol poisoning. However, the CoPc-Pt/C after 300 °C or 635 °C heat-treatment demonstrated significant inactivity for MOR, hence they have a good ability to resist methanol poisoning. The current study indicated that the macrocyclic structure of phthalocyanine is the most important factor to improve the methanol tolerance of CoPc-Pt/C as the oxygen-reduction reaction (ORR) electrocatalyst. The CoPc-Pt based catalyst should be a good alternation for oxygen electro-reduction reaction in DMFC. 相似文献
993.
本文综合研究了螺带式搅拌器在假塑性液体中的混合特性及动力特性,测定了双螺带,内外螺带及螺带螺旋3种类型搅拌器的功率常数Kp和Metaner常数Ks,并得出混匀操作和传质工艺过程的放大准则。 相似文献
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The present study was designed to examine the effects of EFA deficiency (EFAD) on biochemical, functional, and structural
aspects of the kidney in growing and adult rats fed a normal or EFAD diet for 9 wk after weaning. Food and fluid intake (FI),
urine volume, and Na+ and K+ excretions were measured weekly from weeks 4 to 8 by placing the rats in individual metabolic cages for 24 h. At week 9,
Li+ and a 5% water load, respectively, were administered at 14 and 1.5 h prior to glomerular and proximal tubular function studies,
as assessed by 3-h creatinine (CCr) and Li+ (CLi+) clearances. Hematocrit and urine volume; serum and urine [Cr], [Li+], [Na+], and [K+]; and renal FA distribution were also measured. Data [corrected to 100 g/body weight (bw) and presented as means ±SEM] were
significant, at P<-0.05. Despite a similar ingestion of solids from weeks 4 to 7 (weeks 7 to 10 of life), the rats on the EFAD diet showed
a decreased body weight from week 5. From weeks 4 to 8, Fl and urine volume were similar for both groups, but the Fl increased
at week 6 in the EFAD group; 24-h Na+ and K+ excretions were similar at all weeks, except for an increase in the EFAD group for both ions at week 7. In the EFAD group,
CCr and CLi+ decreased by 27 and 56.3%, respectively (385.7±33.4 vs. 280±21.1, and 21.0±2.1 vs. 9.2±1.1 μL/min/100 g; n=9 vs. 10), the latter result suggesting increased proximal reabsorption. The 3-h Na+ and K+ excretions were similar, but the Li+ decreased (0.78±0.06×10−2 vs. 0.32±0.03×10−2 μeq/min/100 g) in the EFAD group, giving additional support to the suggestion. Renal structure was normal and similar for
both groups, but the EFAD group showed a more prominent proximal tubule brush border, together with heavier periodic acid-Schiff
staining in all specimens from weeks 5 to 9. In the EFAD group, FA of the n−9 and n−7 series were higher, but most of the
n−6 series were lower as a percentage of total lipids in the medulla and cortex. Medullary levels of 20∶4n−6 were maintained,
22∶4n−6 declined twice, arachidonic acid was maintained, and 20∶5n−3 was lower. The EFAD diet affected glomerular function,
proximal tubular structure and function, and FA distribution in the rat kidney. 相似文献
998.
本文首先叙述了智能家居的基本概念以及分析了智能家居中的通信技术,分析了WiFi技术在智能家居中的应用优势。接着讨论了串口WiFi的功能,以WiFi插座为例,描述了串口WiFi在智能家居中的具体应用。最后叙述了基于WiFi技术的智能家居系统。 相似文献
999.
基于便携性与实用性考虑,提出一种新的步行者航位推算装置设计。使用三维加速度计与电子罗盘集成芯片LSM303DLHC和陀螺仪集成芯片MPU3050对步行者的实时运动信息进行采集,采用具有ARM Cortex-M3内核的STM32F103RBT6单片机收集传感器数据并对数据进行航位推算处理,将步行者航迹信息显示于TFTLCD上。实验证明,该装置具有较高的推算精度,能满足实际应用需求。 相似文献
1000.
在搭建农机仿真平台时,若虚拟农场里的资源过多,使用Unity3D软件默认的一次性加载机制会使载入过程十分缓慢,用户需要漫长的等待时间.针对这个问题,使用资源动态加载算法优化资源的加载过程,使平台更加流畅运行.本文主要阐述了动态加载算法的原理和实现过程. 相似文献