级联拉曼光纤激光器

只要具备合适的泵源，拉曼光纤激光器可以在很大的波长范围获得激光输出，并可进行宽带调谐。本文从结构、原理和工作特性范围方面对三类级联拉曼光纤激光器的最新进展进行了系统的概述，并指出了其发展趋势。     

Mechanisms involved in the formation of phosphosilicate glass from a phosphoric acid dopant source

This study focused on how the formation of phosphosilicate glass (PSG) film affects the solar cell emitter profile when using an inline ultrasonic mist phosphoric acid source and an inline diffusion furnace. This investigation used a novel approach, whereby the samples were extracted from the inline furnace mid‐process that allowed for the investigation of incompletely formed PSGs. All experimentation was conducted at BP Solar Australia. Total Gravimetric Analysis found that the dilute phosphoric acid dehydrates to form a high concentration phosphoric acid layer on the top surface. X‐ray photoelectron spectroscopy then showed this top surface reacts with the silicon and is reduced to form silicon phosphide. ECV results then demonstrated that the sheet resistance and emitter surface concentration of phosphorus is dependent upon the ratio of phosphide to total phosphorus in the PSG film. Copyright © 2010 John Wiley & Sons, Ltd.     

凝胶掺杂磺化聚苯醚膜性能及水分子的动态吸附

将H3PO4/SiO2凝胶掺杂入磺化聚苯醚质子交换膜基质中,提高了吸水率和质子电导率。研究了水分子在凝胶掺杂型磺化聚苯醚膜中的动态吸附扩散行为,探讨了水与膜基质中磺酸和磷酸基团的相互作用及变化,研究了凝胶掺杂型磺化聚苯醚膜的质子传导过程。结果表明,复合膜的水吸附量显著增加,电导率提高,最高可超过Nafion112(0.0871S·cm-1),达到0.216S·cm-1。凝胶对提高复合膜的电导率具有重要作用,一方面,磷酸基团在磺酸基团和水分子作用下离解产生了离域的H+,增加了可移动的离子数总量;另一方面,凝胶由于强烈的亲水性可吸附水分子形成新的亲水区,并在水合离子的跃迁和传导过程中起着连接点的作用,从而形成更多更长的水分子区,促进了传导质子的离子簇和离子通道的形成,显著提高了电导率。     

喇曼光纤激光器最新进展

喇曼光纤激光器以其众多的优良特性在光通信、光传感以及视觉安全雷达、激光光谱和激光医学等领域有 广阔的发展前景。综合报道了近年来喇曼光纤激光器的最新研究进展,并对几种新型激光器进行了分析。     

基于光纤环形镜的掺磷光纤拉曼激光器

报道了一种由宽带光纤环形镜(FLM)作为腔反射元件的法布里-珀罗腔掺磷光纤拉曼激光器(RFL),并与使用窄带光纤布拉格光栅(FBG)作为高反镜的腔结构进行了对比研究。研究结果表明,使用宽带FLM替代FBG仍可实现掺磷RFL的窄带激光输出,并且可有效避免拉曼激光从高反镜端的泄漏。在相同的输出镜反射率情况下,使用FLM作为高反镜比使用FBG作为高反镜具有更低的振荡阈值和更高的光-光转换效率。当抽运功率为9.45W时,拉曼激光(1.24μm)输出功率为4.31W,激光器斜效率和光-光转换效率分别为57.9%和45.6%。     

CsH5(PO4)2晶须及介孔磷硅酸玻璃的协同制备

以TEOS,H3PO4与CsH2PO4为原料,采用溶胶-凝胶合成方法、以及随后的水热处理和室温时效工艺,生长CsH5 (PO4)2晶须,同时获得介孔结构磷硅酸玻璃基体.CsH5(PO4)2晶须直径为1.5～10μm,磷硅酸盐基体为介孔结构,平均孔径为27nm.晶须生长同时,协同获得介孔结构基体,该工艺路线能够成为一种新...     

An environmentally acceptable primer for galvanized steel: Formulation and evaluation by SVET

The object of this paper was to formulate a two-pack wash primer employing aluminium phosphosilicate as active anticorrosive pigment instead of basic zinc chromate. The anticorrosive action of the primer was evaluated by the polarization technique and the scanning vibrating electrode technique (SVET). The exposed surface was then examined by scanning electron microscopy (SEM) and the surface composition determined by energy dispersive X-ray (EDX) analysis. The primer was finally integrated in a complete paint scheme whose anticorrosive performance was evaluated by the salt spray chamber and electrochemical impedance spectroscopy. The adhesion of the primer plus a painting system was also evaluated by standard ASTM D 3359-90 test method. The wash primer pigmented with zinc chromate was used as reference. Results indicated that basic zinc chromate could be replaced by the more eco-friendly wash-primer containing aluminium phosphosilicate.     

火法精炼紫杂铜除Pb、Fe研究

研究了氧化精炼过程中精炼温度和Cu_2O加入量对紫杂铜除Pb、Fe效果的影响,采用扫描电子显微镜(SEM)和能量弥散X射线光谱(EDS)观察熔渣形貌并对熔渣化学成分进行检测,结合X射线衍射(XRD)对熔渣进行物相分析,同时对磷硅酸盐熔剂的除杂机理进行探讨。结果表明,精炼温度和Cu_2O加入量对除铅效果影响很大,而对除铁效果几乎没有影响;在1 115~1 290℃范围内,随着精炼温度的升高,除铅率逐渐下降;在1 115℃条件下,随着Cu_2O加入量的增加,除铅率呈现上升趋势,最佳Cu_2O加入量为11.35%;磷硅酸盐熔剂具有较好的除杂效果,除铅率最高可达96%,除铁率基本在90%以上;熔体中的Pb、Fe主要通过其氧化物与磷硅酸盐熔剂反应除去,或者被磷硅酸盐熔剂吸附溶解。     

高功率1.48 μm国产掺磷光纤级联拉曼激光器

使用20 W/1.06 μm掺镱双包层光纤激光器作为抽运源, 抽运由300 m国产掺磷光纤和光纤光栅构成的级联拉曼谐振腔, 进行了高功率1.48 μm级联拉曼光纤激光器的实验研究。实验研究了不同反射率的输出光纤光栅对拉曼激光阈值和激光效率的影响。结果表明激光阈值随输出光纤光栅反射率的增加而减小。当使用25.7%的输出光纤光栅时, 激光器具有最大的转换效率, 在入腔抽运功率为12.1 W时, 获得了最大2.8 W/1.48 μm连续波激光输出, 相应的激光斜率效率和转换效率分别为31.3%和23.1%。通过监测1.48 μm激光的最大输出功率, 2 h内的功率波动小于5%。     

Insights into zinc and silver co-substitution over cytotoxicity,antibacterial efficacy,and bone regeneration capabilities of strontium phosphosilicate

A series of Zinc and Silver co-substituted Sr₅(PO₄)₂SiO₄ samples were developed to evaluate the induction of antibacterial properties within the parent material. Structural evaluation of the powder samples showed a good agreement of diffraction data with respective ICDD data cards, and biocompatible secondary phases were found to be present alongside the parent material. A decrease in crystallite size (<40 nm) was observed as the substitution level increased calculated from Scherrer's equation which was also evident in infrared spectra. 6% molar substitution (Zn-3% & Ag-3%) was found to be optimized concentration for the same based on biocompatibility studies involving Hemolytic and MTT assay against MG-63 cell lines. The samples were identical in morphology to Hydroxyapatite and showed excellent bone regeneration capabilities supported by secondary phases confirmed during SBF treatment studies evaluated using diffraction, IR spectra, and electron microscopy that showed signs of apatite seeding over the particles. Both Qualitative and quantitative antibacterial tests in the form of Media poisoning and CFU calculations proved successful acquisition of antibacterial properties at 6% molar substitution. Hence the proposed system can be deemed antibacterial and biocompatible for human application and further evaluated as a possible substitute for Ca–P ceramics for bone regeneration applications.