钱塘江河口段潮动力对污染物稀释扩散作用探讨

本文采用了平面二维有限元数学模型模拟计算了钱塘江河口段的潮汐和潮流场，并建立了二维水质模型，分别在大、小潮情况下对该地区污染物的稀释扩散进行了计算。在此基础上，分析比较了在潮动力条件不同的大潮和小潮情况下污染物稀释扩散情况，发现在排放口附近区域浓度增量在大潮时较低，体现了大潮较强的稀释能力；在远离排放口的区域在大潮时的浓度增量则较高，说明更多的污染物在大潮时被挟带到了更远的地区，体现了大潮较强的扩散能力。     

Up-conversion of Er3＋/yb3＋ co-doped transparent glass-ceramics containing Ba2LaF7 nanocrystals

The up-conversion of Er3+/Yb3+co-doped transparent glass-ceramics 50SiO2-10AlF3-5TiO2-30BaF2-4LaF3-0.5ErF3-0.5YbF3 containing Ba2 LaF7 nanocrystals under the changing of heat treatment temperature and time were investigated.The Ba2 LaF7 nanocrystals precipitated from the glass matrix was confirmed by X-ray diffraction(XRD).The structural investigation carried out by XRD and transmission electron microscopy(TEM) evidenced the formation of cubic Ba2 LaF7 nanocrystals with crystal size of about 14 nm.Comparing with the samples before heat treatment,the high efficiency up-conversion emission of Er3+/Yb3+co-doped samples was observed in the glass-ceramics under 980 nm laser diode excitation.The increase in red emission intensity bands was stronger than the green bands when the crystal size increased.The mechanism for the up-conversion process in the glass-ceramics and the reasons for the increase of Er3+/Yb3+co-doped up-conversion intensity after heat treatment were discussed.     

Effects of crystal field on photoluminescence properties of Ca2Al2SiO7:Eu2+ phosphors

A series of single-phased Ca₂Al₂SiO₇:Eu²⁺ phosphors were synthesized by the solid-state reaction. Their structure and photolumi-nescence properties were investigated by the X-ray powder diffraction （XRD） and excitation and emission spectra in detail. The emission spectra of Ca₂Al₂SiO₇:Eu²⁺ phosphors consisted of blue and green band located at419 and542 nm, respectively. The relative intensities of the blue and green emission changed with Eu²⁺ concentration and were sensitive to the excitation wavelength. The unique photoluminescence property originated from the 4f⁷→4f⁶5d transition of Eu²+ at different energy levels, on which the effect of the crystal field strength was con-sidered to be tailed by adjusting the host composition.     

聚磷酸铵在纺织品上的阻燃整理研究

本文介绍了阻燃剂聚聚磷酸铵的阻燃机理以及在麻布上的应用，并对阻燃麻布的阻燃性及物性进行了研究。     

基于密度泛函理论计算的3d过渡金属掺杂CuGaS2电子结构分析

3d transition metals doped CuGaS2 are considered as possible absorbing material candidates for intermediated band thin film solar cells. The electronic structure and optical properties of 3d transition metals doped CuGaS2 are investigated by using density functional theory calculations with the GGA ＋ U method in the present work. The doping with 3d transition metals does not obviously change the crystal structure, band gap, and optical absorption edge of the CuGaS2 host. However, in the case of CuGa1-χTMχS2 （TM = Ti, V, Cr, Fe, and Ni）, there is at least one distinct isolated impurity energy level in the band gap, and the optical absorption is enhanced in the ultraviolet-light region. Therefore, these materials are band thin film solar ceils. The calculated results are very well better explain them. ideal absorber material candidates for intermediated consistent with experimental observations, and could better explain them.     

高层建筑整体式外挂脚手架

1 高层建筑外脚手架概况 随着我国国民经济持续稳定的增长,城乡建设发展迅速。近年来,为了缓和城市用地紧张和人口稠密的矛盾,有时也是为了扩大地区或单位的社会影响,提高社会地位,创建广告效应,全国各地高层和超高层建筑如雨后春笋地发展。高层建筑施工的特点是体积大;层数多,露天作业多,高层作业多,限于我国组织与施工技术方面产生一系列的矛盾。在投影面积相等的施工场地上,高层建筑施     

磷铝酸盐玻璃中铋离子近红外发光与光学碱度反常现象

研究了铋离子掺杂磷铝酸盐玻璃近红外发光与光学碱度的反常现象. 研究发现, 通过改变碱金属离子半径调节玻璃基质光学碱度, 在808 nm激光激发下铋离子位于1300 nm波段的近红外宽带发光强度随光学碱度的增大而增强, 而在690 nm激光激发下得到的1100 nm波段近红外发光强度则随着光学碱度的增大而减弱. 该玻璃1300 nm波段近红外发光强度与光学碱度依存关系与以往报道结果相反, 且也与1100 nm波段发光特性相反. 根据上述结果可以推测玻璃中1100和1300 nm波段的近红外发光源于不同价态的铋离子, 而该玻璃体系的基质结构自还原作用是导致上述现象产生的主要原因.     

PHBV/PVA复合膜的制备及其性能研究

采用静电纺方法制备聚羟基丁酸/戊酸酯共聚物(PHBV)纤维膜材料,通过调节纺丝液中无水乙醇的含量制备出形态均匀的PHBV静电纺纤维膜。用浇铸法将聚乙烯醇(PVA)涂敷在PHBV静电纺纤维膜上,制备PHBV/PVA复合膜,通过调节PVA的浓度及涂覆量,研究复合膜配比对其力学性能及过滤性能的影响。结果表明,当PVA浓度为8%,PHBV/PVA体积比为2/3时,得到最佳性能的PHBV/PVA复合膜,水通量达到996 L/(m2.h),截留率为86%。     

Upconversion luminescence and color tunable properties in Yb-Tb codoped Ca0.15Zr0.85O1.85 inverse opal

The upconversion (UC) luminescence and color tunable properties of Tb3+ ions were investigated by steady spectral under 980 LD excitation in the Ca0.15Zr0.85O1.85:Yb,Tb inverse opals fabricated by the self-assembly technique in combination with a sol-gel method. The in-hibition of UC emission was inspected if the Tb3+ UC emission band was in the regions of the photonic bandgap, while enhancement of the UC emission occurred if the UC emission band located at the edge of the bandgap. Color modification of the UC emission was successfully ob-tained by the suppression or enhancement effect of the photonic band gap on the UC emission.     

用原位透射电镜技术观察微晶玻璃结晶过程的研究进展

总结了利用原位透射电子显微镜(TEM)技术观察纳米颗粒在玻璃介质中结晶过程的研究进展.原位TEM技术可以提供一个实时记录纳米颗粒形核结晶以及长大的动力学平台,该技术为理解和优化微晶玻璃中纳米颗粒生长机理提供了方法,从而为实现优化纳米颗粒结晶性、形貌以及其物理特性提供了直接途径.此外,还总结了微晶玻璃中纳米颗粒的成核机理...