空气包层大模场面积掺镱光子晶体光纤研究

采用改进的化学气相沉积法和气相液相混合掺杂技术制备大芯径掺镱石英光纤预制棒, 以此作为有源纤芯制备了纤芯直径约90 μm的掺镱双包层光子晶体光纤, 纤芯组分为镱铝磷共掺.双包层光子晶体光纤的模场面积约1330 μm², 纤芯数值孔径0.065,包层数值孔径0.5.首次实现了国产掺镱光子晶体光纤的高功率高效率激光输出, 1 m长的光子晶体光纤激光器实现102 W 激光输出,斜率效率76%.     

用于可见照明的超宽带黄色荧光玻璃

报道了一种新的可用蓝光发光二极管（LED）有效激发的黄色发光玻璃.这种超宽带黄色荧光玻璃样品是在低硅钙铝酸盐玻璃基质中掺杂Ce³⁺,并采用熔融法制备的.通过对吸收光谱、激发光谱、荧光光谱以及不同激发源下荧光强度和峰值波长的测试,分析了样品的发光特性.并利用蓝光LED来激发样品,获得白光发射.从色坐标的计算和玻璃本身的优势来看,这一发光体系在照明和显示等方面具有很大的潜在应用价值.     

便携式土壤重金属探测仪光学结构设计

当前土壤中的重金属污染日益严重,研究开发便携式土壤重金属快速、现场检测技术设备能为土壤重金属污染状况普查提供快速、有效的技术手段。系统中发射光路采用透镜对激光光束会聚并作用到样品;收集光路采用抛物面镜组对等离子体光信号收集并耦合至光纤。分析了激光光束经透镜汇聚后作用到样品时的功率密度,给出了等离子体光信号耦合至光纤端面的光斑大小,并得到整个光学系统的大小尺寸。结果表明,整个光学系统结构紧凑、体积小、光信号耦合效率高,非常适用于便携式土壤重金属快速、现场的探测系统应用。     

共振拉曼光谱方法研究生长期与光照对树椒果实β-胡萝卜素含量的影响

利用共振拉曼光谱技术,在体测量了室内盆栽树椒果实的拉曼光谱.实验结果表明,树椒果实的β-胡萝卜素含量随成熟期临近而增加,成熟期后(约45天)达最高值;没受光照的树椒果实β-胡萝卜素含量明显低于接受阳光照射的果实含量;生长(成熟)前期受阳光照射部位由黄白色变为紫色,其β-胡萝卜素含量高于其他部位.本文为在体分析水果蔬菜中β-胡萝卜素含量提供了方法和依据,也验证了阳光在植物生长中的作用.     

Effect of P2O5 addition on the structural and spectroscopic properties of sodium aluminosilicate glass

The structural and spectroscopic properties of Na₂O-Al₂O₃-SiO₂-xP₂O₅ glasses（x = 0 to 7 mol%） are investigated.Both Raman and IR spectra reveal that discrete phosphate species([PO₄]^-3,[PO3O_1/2]^-2) with low polymerization degree can be formed in the silicate glass.These phosphate structures scavenge non-bridging oxygen ions and cations from the silicate network,resulting in an increase of the glass transition temperature.According to the Judd-Ofelt intensity parameters（Ω₂,Ω₄,Ω₆） of Er³⁺.the asymmetry of local environment around Er³⁺ becomes higher,and the bond covalency between Er³⁺ and O^2-decreases after P2O5 is introduced.In the emission spectra,photo-luminescence intensity increases with increasing P₂O₅ concentration and the spectra are inhornogeneously broadened,revealing that the ligand electric field around Er³⁺ is dramatically changed,and the glass matrix becomes disordered.     

卡莱公司MCR引用

实践证明,将MCR控制工具应用到卡莱轮胎公司中,成功地降低了企业库存,加速了企业资金流动,具有良好的应用性。     

Stimulated Brillouin scattering-induced phase noise in an interferometric fiber sensing system

Stimulated Brillouin scattering-induced phase noise is harmful to interferometric fiber sensing systems.The localized fluctuating model is used to study the intensity noise caused by the stimulated Brillouin scattering in a single-mode fiber.The phase noise structure is analyzed for an interferometric fiber sensing system,and an unbalanced Michelson interferometer with an optical path difference of 1 m,as well as the phase-generated carrier technique,is used to measure the phase noise.It is found that the phase noise is small when the input power is below the stimulated Brillouin scattering threshold,increases dramatically at first and then gradually becomes flat when the input power is above the threshold,which is similar to the variation in relative intensity noise.It can be inferred that the increase in phase noise is mainly due to the broadening of the laser linewidth caused by stimulated Brillouin scattering,which is verified through linewidth measurements in the absence and presence of the stimulated Brillouin scattering.     

Measurements of NO2 mixing ratios with topographic target light scattering-differential optical absorption spectroscopy system and comparisons to point monitoring technique

A topographic target light scattering-differential optical absorption spectroscopy(ToTaL-DOAS) system is developed for measuring average concentrations along a known optical path and studying surface-near distributions of atmospheric trace gases.The telescope of the ToTaL-DOAS system points to targets which are located at known distances from the measurement device and illuminated by sunlight.Average concentrations with high spatial resolution can be retrieved by receiving sunlight reflected from the targets.A filed measurement of NO2 concentration is performed with the ToTaL-DOAS system in Shijiazhuang in the autumn of 2011.The measurement data are compared with concentrations measured by the point monitoring technique at the same site.The results show that the ToTaL-DOAS system is sensitive to the variation of NO2 concentrations along the optical path.     

一种新型紫外正型光刻胶成膜树脂的制备及光刻性能研究

本文合成了N-(p-羧基苯基)甲基丙烯酰胺单体,并将其与N-苯基马来酰亚胺共聚得到共聚物聚N-(p-羧基苯基)甲基丙烯酰胺共N-苯基马来酰亚胺(poly(NCMA-co-NPMI)).将此共聚物作为成膜树脂,与感光剂、溶剂等复配得到一种新型耐高温紫外正型光刻胶.本文探讨了该光刻胶的最佳配方组成和最佳光刻工艺.最佳配方组成为:15%—20%成膜树脂,4.5%—6%感光剂和70%—80%溶剂;最佳光刻工艺为:匀胶30 s(4000 rpm),前烘4 min(90℃),感度为30—35mJ/cm²,在0.2%TMAH溶液显影10 s和后烘2 min(90℃).     

金属泡沫填充薄壁圆管的轴压载荷-位移关系

将泡沫填充圆管的能量吸收视为泡沫与圆管两者之和, 基于包含偏心率效应的直链塑性铰模型和Reddy等对Alexander模型的改进结果, 对圆管的变形模式进行了更改, 以此来反映管壁与金属泡沫之间的相互作用效应, 导出了金属泡沫填充圆管的静、动态轴向平均压溃力的表达式. 通过理论预测与实验的对比, 发现理论预测偏低, 但与实验曲线的趋势保持一致, 比空管与金属泡沫的平均载荷之和略高一些. 此外, 泡沫填充圆管的平均压溃力随填充泡沫平台应力的增大而呈线性增加, 与已有研究结果及实际情况一致, 由此表明了模型的合理性.