LBO腔内和频593 nm激光器

报道了LD纵向泵浦NdYVO4晶体,经腔内和频得到593 nm激光输出的实验研究.采用一个线性平凹腔实现了1 064 nm和1 342 nm双波长连续波振荡,利用LBO腔内和频产生593 nm激光输出.在泵浦功率为1.4 W时得到593 nm的输出功率为70 mW.593 nm光束远场发散角小于1 mrad,光斑椭圆度为0.999,且具有低噪声输出特性.实验结果表明,该结构激光器是获得衍射极限全固体黄激光器的实用方法.     

塞曼火焰原子吸收法测定黄河水体的总硬度

采用原子吸收分光光度法测定黄河水体的总硬度,钙的浓度在0.100～5.00 mg/L、镁的浓度在0.0500～2.00 mg/L范围内分别与吸光度呈线性关系,线性方程分别为A=0.045 5c+8.354×10~(-5)、A=0.514c+8.354×10~(-5),相关系数均为0.9999。黄河水样6次测定结果的相对标准偏差为1.2％,t检验结果表明,该法与EDTA络合滴定法测定结果无显著性差异。     

Sequential molecular vapor elution analysis for the separation and determination of LiCl and NaCl in river waters

The determination of alkali metal chloride in river waters by sequential molecular vapor elution analysis (SMVEA) using a molecular absorption detector (MA) is reported. An improved molybdenum column was developed for SMVEA. An optimum flow rate of carrier gas (pure argon or nitrogen) for separation of metal vapors was 12.0 ml min⁻¹. Lithium chloride and sodium chloride peaks completely separated from potassium, rubidium, and cesium chlorides but CaCl₂, FeCl₂, MgCl₂, and MnCl₂ peaks did not appear at a column temperature of 1000 °C and vaporization temperature of 1000 °C. The appearing order of these metal chlorides was LiCl, NaCl, KCl, RbCl, and CsCl. It was not understood by considering the boiling points of these metal chlorides. The delay of appearing time is due to an interaction between the molecular vapors and inside surface of the column. Under the experimental conditions, the number of theoretical plates was 247 for LiCl and 268 for NaCl in the improved column. Under the optimal experimental conditions, river waters were analyzed for lithium and sodium chlorides. The analytical results agreed well with the recoveries were in the range of 94–105%. By SMVEA, it was found that lithium and sodium chlorides in waters were determined without interference of matrix elements, no chemical treatment for river water samples.     

LDA抽运Nd∶YAG/KTP腔内和频589nm连续波激光器

报道了一种激光二极管阵列(LDA)抽运Nd∶YAG双波长和频黄光激光器.黄激光是由Nd∶YAG晶体的1064 nm和1319 nm谱线腔内和频产生.以KTP为和频晶体,采用Ⅱ类临界相位匹配,在12 W的808 nm抽运功率下,获得了最高功率为430 mW连续波基横模的589 nm黄激光输出,光光转换效率为3.6%,光束质量因子M2<1.2.实验结果表明采用激光二极管阵列抽运Nd∶YAG/KTP腔内和频技术是获得黄激光的高效方法,并可以应用到其它激光增益介质的两条谱线进行腔内和频,获得更多不同颜色的单谱线激光输出.     

雨水和表面活性剂的淋溶对河道底泥中多氯联苯迁移的影响

利用雨水和表面活性剂(LAS、AE9和NPE10)淋溶多氯联苯(PCBs)污染的河道底泥柱,初步探讨了它们对表层底泥中PCBs洗脱量的影响,同时也研究了从表层洗脱出的PCBs随着淋洗液在下层底泥中的纵向迁移。淋洗液包括雨水和浓度均为1500mg.L-1的LAS、AE9、NPE10溶液以及浓度都是1500mg.L-1的AE9+NPE10和LAS+NPE10混和溶液。实验发现:雨水和同浓度的表面活性剂溶液对表层底泥中PCBs洗脱量大小依次为:雨水相似文献   

Electrochemical Detection of Trace Concentrations of Cadmium and Lead with a Boron‐Doped Diamond Electrode: Effect of KCl and KNO3 Electrolytes,Interferences and Measurement in River Water

Parts‐per‐billion levels of cadmium and lead were detected using square‐wave anodic stripping voltammetry with a boron‐doped diamond electrode. Calibration plots (10‐minute deposition time) in KCl and KNO₃ were non‐linear at low concentrations (1–5 ppb) due to the deposition mechanism of these metals. The preferred electrolyte for cadmium was KCl, while lead could be measured in either electrolyte. The lowest concentrations included in the linear portion of the calibration plot (5 minute deposition time) for cadmium were 10 ppb and 50 ppb in KCl and KNO₃, respectively, and 10 ppb for lead in KNO₃. The presence of either lead or copper suppressed the cadmium stripping peak, but the lead stripping peak was unaffected by cadmium, and enhanced by the addition of copper. A river water sample was analyzed for cadmium and lead, and the cadmium results were confirmed using ICP‐AES spectrometry. It was determined electrochemically that a fraction of lead in the river sample was bound by complexing material in the sample.     

含5-(三氟甲基)-2-吡啶甲酸的黄光铱配合物的合成、光物理性质及量化计算研究

利用环金属配体2-(2’,4’-二氟苯基)-4-甲基吡啶(dfpmpy)和辅助配体5-(三氟甲基)-2-吡啶甲酸(tfmpic)合成了一个铱配合物[Ir(dfpmpy)₂(tfmpic)],并测定了该配合物的光物理和电化学性质。在乙腈溶液中,配合物发射黄色磷光,其最大波长位于554 nm,理论计算表明其磷光来自于金属和环金属配体到辅助配体的电荷转移跃迁(₃MLCT 或 ₃LLCT)。     

Simultaneous spectrophotometric determination of phosphate and silicate ions in river water by using ion-exclusion chromatographic separation and post-column derivatization

The simultaneous spectrophotometric determination of phosphate and silicate ions in river water was examined by using ion-exclusion chromatography and post-column derivatization. Phosphate and silicate ions were separated by the ion-exclusion column packed with a polymethacrylate-based weakly acidic cation-exchange resin in the H⁺-form (TSKgel Super IC-A/C) by using ultra pure water as an eluent. After the post-column derivatization with molybdate and ascorbic acid, so-called molybdenum-blue, both ions were determined simultaneously by spectrophotometry. The effects of sulfuric acid, sodium molybdate and ascorbic acid concentrations and reaction coil length, which have relation to form the reduced complexes of molybdate and ions, on the detector response for phosphate and silicate ions were investigated. Under the optimized conditions (color-forming reactant, 50 mM sulfuric acid-10 mM sodium molybdate; reducing agent, 50 mM ascorbic acid; reaction coil length, 6 m), the calibration curves of phosphate and silicate ions were linear in the range of 50-2000 μg L⁻¹ as P and 250-10,000 μg L⁻¹ as Si. This method was successfully applied to water quality monitoring of Kurose-river watershed and it suggested that the effluent from a biological sewage treatment plant was significant source of phosphate ion in Kurose-river water.     

基于现场光谱的潮滩表层沉积物叶绿素-a含量遥感模式

提出了一种可实现潮滩表层叶绿素的现场快速、无损的光学检测方法。利用反射率光谱对我国潮滩表层沉积物叶绿素-a浓度进行了观测试验。基于高光谱650,675及700nm各波段的反射率,提出了用于叶绿素浓度反演的归一化底栖微藻差异指数(NDI-MPB)、及可消除呈直线或近似直线变化的背景噪声光谱的反射谷深度(T-depth)模型。研究结果表明,NDI-MPB指数与表层沉积物(3mm)中的叶绿素-a浓度(2.22～49.36mg.m-2)有极好的线性相关性(r>0.99);以叶绿素-a浓度表征底栖微型藻类生物量,NDI-MPB可用于潮滩表层底栖微型藻类生物量的遥感监测。