Synthesis and photoluminescence properties of a red emitting phosphor NaSr2（NbO3）5：RE3＋（RE=Sm,Pr） for white LEDs

Rare earth Sm3＋, Pr3＋doped NaSr2（NbO3）5 red phosphors were successfully synthesized. X-ray diffraction analysis indi-cated that all the samples were single phased. The luminescence property was investigated in detail by diffuse-reflectance spectra and photoluminescence spectra measurement. Both NaSr2（NbO3）5：Sm3＋and NaSr2（NbO3）5：Pr3＋phosphors showed strong absorption in near ultraviolet region, which was suitable for application in LEDs. When excited by UV light, they both emitted bright red emission with CIE chromaticity coordinates （0.603, 0.397） and （0.669, 0.330）, respectively. The optimal doping concentration of Sm3＋doped NaSr2（NbO3）5 was measured to be 0.04 and that for Pr3＋doped NaSr2（NbO3）5 was 0.01. The integral emission intensity was also measured and compared with the commercial red phosphor Y2O3：Eu3＋. The results indicated that NaSr2（NbO3）5：RE3＋（RE=Sm, Pr） have potential to serve as a red phosphor for UV pumped white LEDs.     

基于使用年限的高性能混凝土配合比设计与试验研究

工程实践证明,现今通常使用的普通混凝土的耐久性具有局限性,就算能够满足抵抗各种环境因素的耐久性要求,其安全性运行年限也较短。因此,研究的目的旨在将现行的混凝土耐久性试验检测的指标引入时间的因素,以此来推知混凝土的耐久性使用年限。通过试验研究发现:采用高性能混凝土配制技术,使用P.O 42.5和I级粉煤灰,当水胶比在0.33以下时,配制出的混凝土具有良好的抗冻性、抗侵蚀性及抗渗性,同时,配制出的混凝土具有较长的使用年限,可至少使用50年。     

新场气田须二段地层水地球化学特征及其石油地质意义

阐述新场地区地质构造背景的同时,在油气水文地质和大量水化学分析测试数据基础上,研究了川西新场气田须二段地层水化学参数的基本特征,勾划了地层水化学参数化学场图,揭示了地层水化学分布规律性,并结合油气研究成果对新场地区含油气性和气田保存条件进行了水文地质评价和预测。对于相关的气田地层水渗流场、地下水成因、单井水产量预测以及储层改造工艺技术具有一定的指导意义。图2表1参10     

钢筋混凝土T梁的加固方案研究

对粘贴钢板加固技术和增大截面加固T形梁进行了全面系统地研究,并通过计算分析,得到了加固后的主梁刚度和承载力提高率。研究表明:通过对主梁进行粘贴钢板加固可有效提高主梁的刚度和抗弯承载力,进而达到延长既有桥梁使用寿命的目的,并为同类桥梁加固提供指导。     

后注浆法钻孔灌注桩在建筑桩基施工中的应用

针对某工程场地分别进行了后注浆钻孔灌注桩施工处理和钻孔灌注桩施工处理,并通过静载荷试验对成桩质量进行验证,指出后注浆施工工艺,可明显改善桩端持力层及桩周条件,在提高桩基综合承载力的同时也有效地减少了地基的沉降量。     

Se-75 Υ射线源在小径薄壁管焊口探伤中的应用

针对检验设备选择,及Se-75射线源特性、工艺方法与辐射防护进行技术分析。阐述了Se-75Υ源在某电厂高温再热器的小径薄壁管焊口探伤中的应用。     

球墨铸铁曲轴的铸造及热处理工艺

针对高性能球墨铸铁曲轴整体对开、平面分型工艺易出现夹砂、气孔等铸造缺陷的问题,重新设计了铸造工艺,采用曲面分型,配以凸凹模板,设计了无芯铸造曲轴分型工艺,简化了操作工序,避免了夹砂、气孔等铸造缺陷的产生,降低了生产成本.为使铸件组织均匀,研制出了曲轴自动连续冷却生产线以及悬挂式旋转风雾冷却装置,均匀冷却后工件的热应力和组织应力分布均匀,减少了工件变形,提高了曲轴的质量,改善了曲轴的性能,实现了多缸曲轴的批量稳定生产.     

废油脂的利用及我国生物柴油的生产状况

介绍了对我国废油脂的回收再利用情况、存在的问题及将其用于生物柴油生产的优势,指出生物柴油的生产及生物柴油产业发展过程存在的问题,并提出了一系列解决对策。最后对生物柴油的发展前景做了展望。     

Cholecystokinin decreases intestinal hexose absorption by a parallel reduction in SGLT1 abundance in the brush-border membrane

The dual lumenaly and vascularly perfused small intestine was used to determine the mechanism by which cholecystokinin octapeptide (CCK-8) decreases the rate of glucose absorption. With CCK-8 in the vascular perfusate the rate of 3-O-methyl-D-glucose absorption decreased, whereas the rate of D-fructose absorption was unaffected. The substrate pool size within the tissue during steady-state transport, in the presence and absence of CCK-8, was estimated by compartmental analysis of the 3-O-methyl-D-glucose washout into the vascular bed. When CCK-8 was included in the vascular perfusate, the absorptive cell pool size decreased when compared with untreated tissue. Both the steady-state hexose absorption data and the washout studies indicated that the locus of action of CCK-8 was the SGLT1 transporter located in the brush-border membrane. The SGLT1 protein abundance in isolated brush-border membranes, as quantified by Western blotting, showed a decrease that paralleled the decrease in the steady-state transport rate induced by CCK-8. These results indicate that CCK-8 diminishes the rate of intestinal hexose absorption by decreasing SGLT1 protein abundance in the brush-border membrane of the rat jejunum and therefore provides evidence for acute enteric hormonal regulation of the rate of glucose absorption across the small intestine.     

Identification of bovine rotaviruses in Venezuela: antigenic and molecular characterization of a bovine rotavirus strain

Digestion by restriction enzymes has been carried out on polymerase chain reaction products of the mitochondrial DNA control region of round sardine (Sardinella aurita) samples coming from the Eastern Atlantic and the Mediterranean Sea. The results show i) that, though the habitat is continuous, there is no gene flow between the two basins where two genetically differentiated groups can be recognized, ii) that each basin is genetically homogeneous and, iii) that the haplotypic diversity in the Mediterranean is between two and three times smaller than that observed in the Atlantic. These results can hardly be explained by a recent colonization from the Eastern Atlantic. This suggests that, for S. aurita and some other species, the Mediterranean Sea is genetically little influenced by the Eastern Atlantic.