Ce3+离子激活的SrB4O7的VUV光谱

Ce³⁺只有一个4f电子,具有最简单的4f¹5d⁰基态结构,其激发光谱直接反映了5d轨道的能量状态。由于同一基质晶格相同格位上不同稀土离子受基质晶体场影响相近,所以根据Ce³⁺离子的光谱可以推测和分析其他稀土离子的5d轨道能量,是研究其他稀土离子f-d跃迁的基础。采用高温固相法合成了Ce³⁺离子激活的SrB₄O₇发光体,测定了样品在130~350nm波长范围的激发光谱和相应的发射光谱。指认了VUV激发光谱上Ce³⁺离子的5个4f¹→4f⁰5d¹跃迁激发带,讨论了SrB₄O₇的基质吸收带和Ce³⁺的5d轨道在SrB₄O₇中的晶体场劈裂、5d轨道能级重心及SrB₄O₇:Ce³⁺的发射光谱和Stokes位移。     

An improved broad-spectrum room acoustics model including diffuse reflections

More and more literature has paid attention to the diffuse reflections in enclosed space during the past few years. In this paper, the current computer models including diffuse reflections have been reviewed briefly at first. Then, to realize the broad-spectrum simulation for enclosed sound fields including diffuse reflections, an improved ray-tracing algorithm, which combines the splitting coefficient diffusion model and a dynamic sound ray receiving method, has been given. The algorithm can deal with broad frequency bands simultaneously by using the frequency independent splitting coefficient. To test the algorithm and also to investigate the significance of the diffuse reflections in enclosed sound fields, experiments have been made in three spaces including a virtual room and two real rooms. The results and discussions have validated the applicability of the improved algorithm and they have also shown that diffuse reflections can improve room acoustic prediction, although it not always promote a sound field to be more diffused.     

自发喇曼成像法在线测量流场组分浓度(II)

 介绍了利用自发Raman散射光谱测量低压气流组分绝对浓度的方法，在流动状态下得到了不同压力下的自发喇曼散射光谱，检测最低压力为133帕；对于含N₂氧气流在已知N₂浓度时实时标定检测了O₂的绝对浓度，测量误差小于8%。     

催化动力学测定食品中痕量甲醛

在H2SO4介质中,甲醛可灵敏催化溴酸钾氧化中性红的褪色反应,研究了该指标反应的动力学参数,建立了动力学光度法测定痕量甲醛的新方法。该方法的检出限为4.08×10-9g/mL,线性范围在0-1.0μg/25mL。用水蒸汽蒸馏法蒸馏甲醛用于食品中甲醛的测定,结果满意。     

部分相干光学成像系统的光学传递函数和像质评价准则

根据光学成像理论，建立了部分相干成像光学系统的光学传递函数。该函数与非相干成像光学系统传递函数相同，因而部分相干成像和非相干成像两者的光学系统波面像差公差标准也是相同的。这一点解释了显微镜光学系统的光学设计惯用法则：镜头像差公差标准的选择，并不因为采用成像照明方式的不同而有所差异。     

铜(Ⅱ)/H2O2对多巴氧化作用的紫外-可见光谱研究

本文采用紫外－可见光谱法研究了在不同pH条件下铜（Ⅱ）／H2O2对多巴氧化作用的影响。结果表明，pH可影响铜离子催化多巴氧化成黑色素的效率，在弱酸性环境下铜（Ⅱ）的催化作用要比pH7.4时强。     

粗糙波面光学传递函数像质评价准则和粗糙度公式理论

建立了包含波面像差和粗糙度影响的粗糙波面光学传递函数及其像质评价准则，讨论了粗糙度公差的理论和标准。     

SOME PROPERTIES OF A CLASS OF INTERCHANGE GRAPHS

§１ＩｎｔｒｏｄｕｃｔｉｏｎＬｅｔＧｂｅａｃｏｎｎｅｃｔｅｄｇｒａｐｈｗｉｔｈｖｅｒｔｅｘ－ｓｅｔＶ（Ｇ）ａｎｄｅｄｇｅ－ｓｅｔＥ（Ｇ）．Ｄｅｎｏｔｅｂｙｅ＝（ｘ，ｙ）ｔｈｅｅｄｇｅｊｏｉｎｉｎｇｔｈｅｖｅｒｔｉｃｅｓｘａｎｄｙｏｆＧ．Ａｍ－ｃｌｉｑ...     

Synthesis,characterization and in vitro cytotoxicity screening of some triarylbismuth(V) di(N‐salicylidene)amino carboxylates and the crystal structure of (2‐HOC6H4CHNCH2CO2)2Bi(C6H5)3

Four novel triarylbismuth(V) di(N‐salicylidene)amino carboxylates were synthesized. Their structures were confirmed by IR, ¹H NMR, ¹³C NMR and elemental analysis. The crystal structure of (2‐HOC₆H₄CH?NCH₂CO₂)₂BiPh₃ was determined by X‐ray diffraction. The in vitro cytotoxicity of all compounds against three human cancer cells (HL‐60, BGC‐823 and MDA‐MB‐435) at 10 µM are reported. Copyright © 2005 John Wiley & Sons, Ltd.     

Time-resolved Luminescence-based Chemosensor for Fluoride Anion

Design and synthesis of new chemosensors for fluoride anion (F-)1-6 have been of interest to chemists for many years, because F- plays a crucial role in the dental care5 and the treatment of osteoporosis7. Recently, the fluorescent chemosensors of fluorid…