选择性发射极晶体硅太阳电池的二维器件模拟及性能优化

利用PC2D二维模拟软件对选择性发射极晶体硅太阳电池(SE电池)进行了器件模拟和参数优化的研究.在对丝网印刷磷浆法制备的SE电池的实测典型电流-电压曲线实现完美拟合的基础上,全面系统地研究了栅线、基区、选择性发射区和背表面场层等的参数对电池性能的影响.模拟表明:基区少子寿命、前表面复合速度和背表面复合速度是对电池效率影响幅度最大的三个参数.在所研究的参数范围内,当基区少子寿命从50μs上升到600μs时,电池效率从18.53%上升到19.27%.低的前表面复合速度是使发射区方块电阻配比优化有意义的前提.要取得理想的电池效率,背表面复合速度需控制在500 cm/s以下.此外,对于不同的前表面复合速度,电池效率的最大值总是在50—90Ω/□的重掺区方阻、110—180Ω/□的轻掺区方阻的范围内取得.对不同的栅线数目,重掺区宽度与栅线间距之比为32%时,电池的效率最高.另外,在主栅结构保持较低面积比率的前提下,主栅数目的增加也可提高效率.最后,通过优化p型SE电池的效率可达到20.45%.     

Indirect Determination of Sulfadiazine by Cloud Point Extraction/Flow Injection‐Flame Atomic Absorption (CPE/FI‐FAAS) Spectrometry

An indirect simple and rapid cloud point extraction is proposed for separation and preconcentration of sulfadiazine and its determination by flow injection‐flame atomic absorption spectroscopy (FI‐FAAS). The sulfadiazine from 35 mL of solution was readily converted to silver sulfadiazine upon addition of silver nitrate (9.7 × 10^‐5 mol/L). Then, Triton X‐114 a non ionic surfactant was added and the solution was heated to 60 °C. At this stage, two separate phases was formed and silver sulfadiazine enters the surfactant rich phase of non‐ionic micelles of Triton X‐114. The surfactant‐rich phase (～50 μL) was then separated and diluted to 300 μL with acidic methanol. The concentration of silver in the surfactant‐rich phase which is proportional to the concentration of sulfadiazine in sample solution was determined by FI‐FAAS. The parameters affecting extraction and separation were optimized. Under the optimum conditions (i.e. pH 2‐10, silver concentration (9.7 × 10 ^‐5 mol/L), Triton X‐114 (0.075% v/v) and temperature 60 °C) a preconcentration factor of 117 and a relative standard deviation of 4.9% at 37 μg L^‐1 of sulfadiazine was obtained. The method was successfully applied to analysis of milk, urine and tablet samples and accuracy was determined by recovery experiments.     

Performance Evaluation of Nickel Separation and Extraction Process from Simulated Spent Cr/Ni Electroplating Bath Solutions by ELM Process Using LIX63 and PC88A

The study was conducted to investigate synergistic extraction of nickel from simulated spent Cr–Ni electroplating bath solutions by emulsion liquid membrane (ELM) process using 5,8-diethyl-7-hydroxydodecan-6-one oxime (LIX 63) and 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (PC88A) as carriers. The importance of ELM composition and the properties of simulated spent electroplating bath solution have been optimized to synergistically extract nickel. The important parameters affecting the nickel extraction efficiency and ELM stability, such as acid concentration, stripping solution type and concentration, extractant concentration, surfactant concentration, and phase ratio, were experimentally studied. Along with obtained results, higher than 99% of nickel was selectively extracted within 30 minutes from simulated electroplating bath solutions that their metal concentrations was in the range of 100–500 mg/L. in the optimum conditions. The higher separation factor value of nickel over chromium (β_Ni/Cr) was obtained as 898. As a result, the nickel extraction kinetic was found to depend on PC88A, since extraction mechanism of PC88A is slower than that of LIX63. So, the combined use of LIX63 and PC88A improved the selective extraction of nickel in that process.     

硫辛酸片含量与降解物的高效液相色谱测定研究

建立了硫辛酸片中硫辛酸及其降解物快速测定的高效液相色谱方法。采用Waters XBridge色谱柱(5μm,150 mm×4.6 mm),流动相为0.05 mol/L磷酸二氢钾溶液(磷酸调至pH 2.5)-乙腈-甲醇(50∶45∶5),流速为1.0 mL/min,进样量为20μL,二极管阵列检测器,检测波长为220 nm,全波长扫描范围为200～400 nm,柱温为室温。结果表明,在上述色谱条件下,硫辛酸浓度在0.4～20.0 mg/L范围内线性关系良好(r=0.999 9);其检出限为0.2 mg/L;定量下限为0.6 mg/L;精密度RSD(n=12)为3.4%;加标回收率为100.9%,RSD为2.0%。该法简便、快速、准确、选择性好、灵敏度高,可用于硫辛酸片含量与降解物的测定。     

高效液相色谱法测定葛根芩连片中的葛根素

建立高效液相色谱测定葛根芩连片中葛根素含量的方法。以体积分数50%的甲醇为提取液对样品超声提取20 min,采用DiamonsilTMC18(250 mm×4.6 mm,5μm)色谱柱,以甲醇–乙腈–水(体积比8∶12∶80)为流动相,流速为1.0 mL/min,检测波长为250 nm,柱温为30.0℃,进样量体积10μL。在最佳实验条件下,葛根素与其它物质能完全分离,葛根素的质量浓度在5.43~543.2μg/mL范围内与色谱峰面积呈良好的线性,线性相关系数r=0.999 9,方法检出限为3.50μg/mL(S/N=3)。方法加标回收率为100.0%,测定结果的相对标准偏差为1.6%(n=6)。该方法简单、快速、重现性好,适用于葛根芩连片中葛根素的测定。     

食品中碘的光谱电化学法测定

本文研究了用光谱电化学法测定食品中的碘，探讨了最佳的测定条件，用于海带，海带表层盐及模拟碘盐中碘的测定，结果满意，回收率高，抗干扰力强，操作快捷，方法简单易行。     

部分空气桥式硅膜二维光子晶体

描述在Si基底上制备带隙在近红外波段部分空气桥式二维光子晶体（PC）.选用HF酸溶液作为腐蚀液，利用聚焦离子束刻蚀技术直接刻蚀出具有三角形空气洞结构的二维PC，并测出了二维PC完整的第一带隙透过谱的带隙范围为123—155μm.实验测得的透过谱与理论计算的空气桥式二维PC的计算结果一致.类TM0模的存在减小了带隙的宽度.由于部分SiO2支撑桥式平板，二维PC易于按所需尺寸进行制备.同时，通过改变平板下的支撑材料，可以制出有源的PC，利用这种机理可以把光从支撑材料中引出. 关键词： 二维光子晶体 带隙 平板波导     

Gas-Liquid Chromatographic Determination of Pipemidic Acid

A gas chromatographic method was established for the quantitative analysis of pipemidic acid. The method is based on alkylation of pipemidic acid with diazomethane catalyzed by boron trifluoride. The sample was chromatographed on a stainless steel column packed with 5% OV-101 on Chromosorb G-HP and n-octacosane was used as an internal standard. Quantitation is achieved by measuring peak-height ratio. The method was satisfactorily applied to the analysis of pipemidic acid in tablet.     

嵌入式频率特性分析仪的设计及实现

研究设计基于PC104和FPGA的嵌入式频率特性分析仪。该分析仪采用虚拟仪器的概念,以PC104 CPU为主控单元,通过FPGA控制D/A、A/D芯片时序,输出全频率范围内的正弦波并采样存储系统激励信号及输出响应,最后通过CPU算法处理得到系统频率特性。实验结果表明：该仪器人机界面友好,测量速度快,测试波形与理论计算波形能较好吻合。     

NMR metabolic profiling of organic and aqueous sea bass extracts: implications in the discrimination of wild and cultured sea bass

The nuclear magnetic resonance (NMR) technique was used as analytical tool to determine the complete metabolic profiling of sea bass extracts: water-soluble metabolites belonging to different classes such as sugars, amino acids, dipeptides and organic acids as well as metabolites soluble in organic solvent such as lipids, sterols and fatty acids were identified. The metabolite profiling together with a suitable statistical analysis were used to discriminate between wild and cultured sea bass samples. Preliminary results show that discrimination between wild and cultured sea bass was obtained not only using fatty acid composition but also cholesterol and phosphatidylethanolamine and some water-soluble metabolites such as choline, trimethylamine oxide, glutamine, fumaric and malic acids.