红橙蓝发光Ce/Mn:Cd0.5Zn0.5B4O7材料和体系多重能量传递

用高温固相法首次制备出红橙蓝3种光发射为一体的(Cd0.38Ce0.06/Mn0.03)Zn0.5B4O7光致发光系列材料,由XRD测得(Cd0.38Ce0.06Mn0.03)Zn0.5B4O7的晶胞参数a、b、c分别为1.3959、0.8134、0.8658nm,属于正交晶系,Pbca空间群。Ce/Mn:Cd0.5Zn0.5B4O7的光谱显示:由285、370、296nm紫外光激发,分别呈现Mn2+的4T1(4G)→6A1(6S)和Ce3+的5d→2F5/2,2F7/2能级跃迁发射以及发射强度比相近的470和630nm的复合光发射。当Ce3+和Mn2+共掺杂时它们互为激活剂和敏化剂。在荧光体Ce/Mn:Cd0.5Zn0.5B4O7中存在极少见的基质、Ce3+和Mn2+的多重能传递,其中以Ce3+Mn2+的双向能量传递为主。助熔剂CaF2和KCl都能降低合成温度和增加发光强度,但对Ce3+和Mn2+发射光谱有不同影响。     

柠檬酸活化赤泥对亚甲基蓝染料废水的吸附净化作用

采用一种活化赤泥吸附剂用于水溶液中亚甲基蓝的吸附净化.考察吸附剂用量、pH值、亚甲基蓝浓度、吸附温度和吸附时间对活化赤泥吸附性能的影响规律.结果表明:采用稀柠檬酸活化处理可显著提高赤泥对染料分子的吸附效率;吸附率随吸附剂用量增加而增加,随初始亚甲基蓝浓度和温度升高而降低;测得活化赤泥对亚甲基蓝的最大吸附容量为30 mg/g,吸附过程符合Langmuir等温吸附模型;吸附动力学过程可用准二级动力学方程描述,计算出吸附过程的表观活化能为9.88 kJ/mol.对吸附过程焓和熵值的计算结果表明,活化赤泥对水溶液中亚甲基蓝染料的吸附是一个自发的放热过程.     

A novel indicator system for catalytic spectrophotometric determination and speciation of inorganic selenium species (Se(Ⅳ), Se(Ⅵ)) at trace levels in natural lake and river water samples

A novel catalytic kinetic method is proposed for the determination of Se(Ⅳ), Se(Ⅵ), and total inorganic selenium in water based on the catalytic effect of Se(Ⅳ) on the reduction of Celestine blue by sodium sulfide at pH 7.0 phosphate buffer. The fixed-time method was adopted for the determination and speciation of inorganic selenium. Under the optimum conditions, the two calibration graphs are linear with a good correlation coefficient in the range 2-20 and 20-200 μg·L-1 of Se(Ⅳ) for the fixed-time method a...     

FeCl3-NiCl2石墨层间化合物光催化性能初探

石墨层间化合物是一个近似的二维物理系统,人们对其独特的电学和磁学性质已开展广泛研究,但尚未见到有光催化活性方面报道。本文采用混合加热法制备了多种阶结构的FeCl3-NiCl2石墨层间化合物。将其添加到甲基蓝溶液中,通过紫外光辐照、阳光辐照和暗箱放置等试验发现所合成的石墨层间化合物具有光催化活性,且混合阶结构的样品光催化活性更高。     

壳聚糖吸附溴百里香酚蓝的机理研究

考察了溶液初始pH值和温度对吸附性能的影响,借助吸附等温线研究了壳聚搪吸附溴百里香酚蓝的吸附性能和机理,结果表明,在pH值为3.4时,壳聚搪对溴百里香酚蓝的吸附容量达到最大.温度对壳聚糖吸附溴百里香酚蓝的影响较小,随着温度的升高,吸附能力降低.计算得到吸附过程的热力学参数△G0,△H0和△S0分别为-19.74kj/m...     

基于光纤倏逝波传感器的磷酸根离子检测

提出了利用光纤倏逝波传感器通过光吸收方法来测量溶液中磷酸根离子浓度的新方法。将通信用标准单模光纤（SMF）局部腐蚀到接近芯层后放入不同浓度的磷钼蓝溶液中,当以磷钼蓝光吸收峰值为探测光波长时,光纤表面的倏逝波会部分被溶液吸收,通过测量光纤输出光强来计算溶液中的磷酸根离子浓度。实验结果表明,磷钼蓝溶液中磷浓度为0．04～O...     

用Berreman 4×4矩阵法计算胆甾相液晶的选择性反射

利用Berreman 4×4矩阵法对胆甾相液晶的选择性反射特性进行了计算模拟,从模拟结果分析了胆甾相液晶的蓝移现象和反射率与盒厚的关系。     

Optimization of CdTe thin‐film solar cell efficiency using a sputtered,oxygenated CdS window layer

A major source of loss in cadmium sulfide/cadmium telluride (CdS/CdTe) solar cells results from light absorbed in the CdS window layer, which is not converted to electrical current. This film can be made more transparent by oxygen incorporation during sputter deposition at ambient temperature. Prior to this work, this material has not produced high‐efficiency devices on tin oxide‐coated soda‐lime‐glass substrates used industrially. Numerous devices were fabricated over a variety of process conditions to produce an optimized device. Although the material does not show a consistent increase in band gap with oxygenation, absorption in this layer can be virtually eliminated over the relevant spectrum, leading to an increase in short‐circuit current. Meanwhile, fill factor is maintained, and open‐circuit voltage increases relative to baseline devices with sublimated CdS. The trend of device parameters with oxygenation and thickness is consistent with an increasing conduction band offset at the window/CdTe interface. Optimization considering both initial efficiency and stability resulted in a National Renewable Energy Laboratory verified 15.2%‐efficient cell on 3.2‐mm soda‐lime glass. This window material was shown to be compatible with SnO₂‐based transparent conducting oxide and high resistance transparent coated substrates using in‐line compatible processes. Copyright © 2015 John Wiley & Sons, Ltd     

Facile synthesis and catalytic properties of single crystalline β-MnO2 nanorods

Single-crystalline β-MnO₂ nanorods were successfully synthesized through facile reflux treatment of KMnO₄ and MnSO₄ in HNO₃ solution. TEM and SEM images show that the synthesized β-MnO₂ nanorods exhibited diameters of 20–50 nm, and lengths that ranged from approximately 0.5 to 2.0 μm with decreasing HNO₃ concentrations from 0.8 to 0.1 mol/L. The β-MnO₂ nanorods underwent three primary evolutionary stages over time. They exhibited excellent catalytic properties for the degradation of methylene blue (MB) by a Fenton-like reaction.     

电感耦合等离子原子发射光谱法测定食品添加剂亮蓝中的杂质元素

采用硝酸和双氧水消解体系,使用电感耦合等离子体原子发射光谱仪（IcP-AEs）检测食品添加剂亮蓝中Ph、Mn、cr的含量。结果表明,方法的检出限为0．005～0．015p∥mL,回收率为95．30％～103．9％,RSD小于3．05％。该方法简便、快速、准确,适用于检测食品添加剂亮蓝中的杂质元素。