胃复安电极的研制及应用

本文报道了胃复安选择性电极的研制及应用.研究了活性物膜含量、增塑剂、电极结构等因素对电极性能的影响.以四苯硼作为离子交换体时,电极的线性范围为2.0×10~(-2)～8.0×10~(-6)mol/L,斜率57.4mV/pC,检测下限4.2×10~(-6)mol/L.用于胃复安的分析结果良好,回收率在97～104%之间,片剂胃复安的含量测定与药典法一致.     

苯海索电极的研制和应用

本文以苯海索—四苯硼为活性物质,邻苯二甲酸二正辛酯等为增塑剂,研制成苯海索电极。该电极在0.05～2mg/ml 和10~(-2)～10~(-4)M 苯海索标准溶液中呈线性关系。用该电极测定盐酸苯海索及片剂含量和均匀度,均得到满意结果。本法简便、快速。     

电势滴定法测定溶度积常数 Ksp

以自测或文献报道的六组电势滴定数据，代入本文导出的溶度积常数ＫＳＰ关系式，所得有关的ＫＳＰ值与文献值相符，说明该法具有一定的可靠性，且测试方便，计算简单，本文还用自制的四苯硼根电极为指示电极，以四苯硼钠为滴定剂，利用上法测定和计算了尚未报道的３６种四苯硼盐的深度积常数。     

离子缔合型离子选择电极的研究—ⅩⅣ.硼—苯羟乙酸络阴离子电极

本文报道一种硼－苯羟乙酸络阴离子电极。电极对硼－苯羟乙酸络阴离子的线性响应下限为６×１０＾－６ｍｏｌ／Ｌ，斜率５９ｍＶ／ｐＣ（２５℃）。对其它阴离子的选择性优于氟硼酸根电极。用此电极测定了稀土合金中的硼。     

用TPB电极测定RE（TMSO）8（TPB）3中的TPB含量

TPB 为四苯硼酸根的缩写,TPB 的测定方法有重量法、萃取滴定法和孔雀绿为显色剂的光度法等。TPB 电极作为滴定剂电极的研究较多,但尚无用于 TPB 分析的报导。本文以 DTOA-TPB 为活性材料,以 DBP 一氯苯为溶剂制成 PVC 膜 TPB 电极,避免了文献中所用的毒性较大的 DBP 一硝基苯溶剂。并用该电极为指示电极,N—CPC 为滴定剂,成功地测定了环丁基亚砜四苯硼稀土络合物中的四苯硼酸根含量。     

PVC石墨涂膜尼古丁电极

尼古丁是一类存在于烟草中的生物碱,具有毒性,其含量是烟草质量控制指标。Efstathiou 等以四(间—氯苯)硼—尼古丁为活性物溶于硝基苯中所制成的液膜烟碱电极,其线性范围为8×10~(-2)～10~(-5)M。我国周燕真等以四苯硼—尼古丁为活性物所制成的 PVC 膜烟碱电极,其线性范围为10~(-1)～2.8×10~(-5)M。本文比较了多种活性物,选择硅钨酸为活性物,并制成石墨涂膜电极,电极性能优于前文献报道,其线性范围为10~(-1)～10~(-6)M,检测下限达7.4×10~(-7)M,对烟草粉末、烟草浸膏及各种提取液中尼古丁含量测定结果表明,方法迅速、简便、其测定结果与经典法一致。     

用氟硼酸根电极电位滴定法间接测定磷酸二氢钠中的硫酸根

R.J.Levins和R.M.Ikeda在1965年提出了用四苯硼化钠直接电位滴定聚乙二醇及其衍生物;随后在1971年R.J.Levins同样利用聚乙二醇、钡和四苯硼化钠生成的(钅羊)盐沉淀这一性质,试制成了钡离子选择电极;殷学锋等成功地应用四苯硼酸根电极以四苯硼化钠滴定钡离子和镀铬液中的硫酸根。我们以氟硼酸根电极为指示电极,在聚乙二醇(PEG—600)存在下,加入过量的钡标准溶液沉淀硫酸根,然后用四苯硼化钠     

铊（1）离子电化学传感器的研究2.以30—冠—10铊（1）离子电极测定铊（1）

以合成的四种３０－冠－１０衍生物中性载体制备了ＰＶＣ膜铊（１）离子电极，探讨了冠醚结构，增塑剂，添加物与电极性能的关系，以１０＾－２ｍｏｌ／Ｌ醋酸镁为离子强度调节剂，邻苯二甲酸二丁酯增塑的添加有四（对氯苯）硼钾的四叔丁基二苯并－３０－冠－１０铊（１）电极的线性响应范围为１×１０＾－５～５×１０＾－２ｍｏｌ／Ｌ（ＴｌＮＯ３）Ｋ＾ｐｏｔｔ１，ｋ为０．１８。同时应用该电极和缬氨霉素钾电极作为双指示电极，     

离子缔合型离子选择电极的研究Ⅶ.PVC膜铯离子选择电极的研制

铯离子选择电极研制,国外曾报道过四苯硼铯液膜型、冠醚—PVC 膜型和非均相固膜型等类型。但四苯硼铯—PVC 膜铯电极未见文献报道。本文在离子缔合型阴离子选择电极研究的基础上,报道一种以四苯硼铯为活性物质的PVC 膜铯电极——离子缔合型阳离子电极。经过活性剂、溶剂、增塑剂的筛选试验和膜配方配比试验、确定膜的最佳组成为:四苯硼铯的硝基苯饱和溶液50%、邻苯二甲酸二丁酯30%、聚氯乙烯20%。     

盐酸氟桂嗪离子选择性电极的研制

本文报导了所研制的盐酸氟桂嗪离子选择性电极。基于不同的离子缔合物，含量及增塑剂对电极性能的影响，采用正交设计法来综合考察了它们的交互作用，筛选了电极膜的组成，测试了电极的性能，结果表明：以盐酸氟桂嗪－四苯硼钠离子缔合物为活性物质，ＤＢＰ或ＤＯＰ为增塑剂制成的ＰＶＣ膜电极的性能最佳，其响应范围为１．０×１０＾－４－５×１０＾－３ｍｏｌ／Ｌ，检测下限为３．５×１０＾－５ｍｏｌ／Ｌ，响应斜率为５８ｍＶ／     

利用化学计量学方法解析有机污染物降解的动力学过程

利用因子分析、数值遗传算法等化学计量学方法研究了电催化降解有机污染物的动力学过程。以Ti/SnO2＋Sb2O3催化电极为阳极对偶氮类染料甲基橙进行电催化降解为研究对象,采用紫外－可见光度法为测量手段,通过对降解过程中测得的不同波长、不同降解时间的两维吸光度矩阵进行解析,获得了降解过程中存在的组分数、降解的动力学模型等信息。研究表明,甲基橙在Ti/SnO2＋Sb2O3电极上的氧化降解的动力学过程符合连串反应模型,反应过程中产生了带苯环结构的中间体。     

一种磷酸根离子选择电极的测量与补偿

研究了基于金属钴作为敏感材料制成的磷酸根离子选择电极,设计了一种与之配套使用的数据采集系统,用于动态记录和显示被测溶液的电势响应。通过实验建立了以磷酸根离子选择电极的响应电势和溶液pH值为自变量,离子浓度为因变量的数学模型。实验结果表明:建立的模型能很好地拟合响应过程曲线,补偿pH值变化对电极测量的影响,为磷酸根离子选择电极的开发和应用提供了依据。     

一种新型的铬（Ⅲ）离子选择性电极的研制与应用

以水杨醛和硫代氨基脲合成的席夫碱水杨醛缩-硫代氨基脲为中性载体,将其与碳粉混合,以液体石蜡为粘合剂,制备了新型的铬（Ⅲ）离子选择性电极。在室温下,电极对Cr3＋的能斯特响应浓度范围为4.00×10-7～1.00×10-2mol/L,斜率为20.31mV/dec,检测下限为1.58×10-7mol/L。电极的响应时间小于20s,pH使用范围广（3.20～5.80）,稳定性好,使用寿命长。在选定的条件下,用固定干扰离子法（FIM）考察了10余种离子的干扰情况,结果显示,电极对Cr3＋具有较好的选择性。以该离子选择性电极为指示电极,饱和甘汞电极为参比电极,用直接电位法对废水中的Cr3＋进行测定,结果令人满意。     

Direct Fabrication of Nanoscale Light Emitting Diode on Silicon Probe Tip for Scanning Microscopy

We have fabricated a silicon microprobe integrated with a nanometer-sized light emitting diode (Nano-LED) on the tip. This paper describes the fabrication procedure and preliminary topographic testing results. The silicon probe with electrode pattern was made by wet-etching a silicon-on-insulator wafer using oxide as the mask. Subsequently, the probe tip was cut using a focused ion beam (FIB) to form a 150 nm-wide gap. Semiconductor nanoparticles (CdSe/ZnS core-shell nanoparticles) were electrostatically trapped and excited within the electrode gap made on the probe tip. The LED-tip is approximately 150 nm 150 nm. The nano-LED light intensity and current were measured as a function of the driving voltage up to 25 V. In addition to the electroluminescence peaks from the CdSe particles, possible emission from silicon dioxide doped in the FIB milling process was also observed in the measured spectra. Basic mechanical characteristics of the silicon probe were measured by mounting the probe on a tuning fork in a standard near-field scanning optical microscopy (NSOM) set up. It was observed that the drag force reduces the probe oscillation as the vibrating tip approached the near-field of the sample surface. The topographic images of a chromium test pattern on a glass substrate were successfully acquired by keeping the probe tip within roughly 5 nm from the sample surface. Although the probe tip shape and the location of the Nano-LED are yet to be further optimized before realizing near-field optical scanning experiment, the result showed its great promise as a new type of NSOM tip with the ldquoon-proberdquo light-source.     

氧化物电极在氧化锆氧传感器上的应用

用三电极法测量了La1-xSrxMO3 (M :Co ,Mn ,Fe) /ZrO2 电极系统在 40 0～ 80 0℃温度范围内的极化曲线 ,用数学模拟方法从中分离出电化学过电位 ,发现La0 .5Sr0 .5CoO3 的电极阴、阳极特性相近 ,而La0 .5Sr0 .5MnO3 作阴极时的活性高于阳极 ,并且La0 .5Sr0 .5MnO3 阴极已成功应用于工作温度低于 80 0℃下的ZrO2 电压型氧传感器中。     

电化学氧化锆氧传感器的多孔铂电极(连载二)——(二)多孔铂电极的评价指标分析

测量了表面电阻值不同的两个电极试样的厚度及直流极化特性曲线,并由此分析了以表面电阻值作为电极评价指标的模糊性,提出了以电极极化程度来评价电极性能的概念。     

A MEMS-based pyramid micro-needle electrode for long-term EEG measurement

The microelectromechanical systems process including cutting, isotropic wet-etching and sputtering was used to fabricate a pyramid micro-needle electrode, which could be applied in long-term electroencephalogram (EEG) measurement. A penetrating testing and comfort survey was presented to optimize the parameters of applying force and penetrating depth in order to make user comfort, safe and free of pain and bleeding. To investigate the performance of the micro-needle electrode, three micro-needle electrodes with different arrays were deployed to perform skin–electrode contact impedance experiments. Moreover, the impedances in time domain were measured to verify the feasibility of long time measurement. At last, EEG signals were recorded directly by three pairs of standard wet/micro-needle electrodes and the power spectrum density (PSD) was presented between standard wet electrode and micro-needle electrode to estimate signal quality. Based on the results of EEG signals and the PSD, the micro-needle electrode can be as a biopotential electrode for recording EEG with low skin–electrode contact impedance.     

Modelling and characterization of AlN-actuated microcantilevers vibrating in the first in-plane mode

The characterization of the first in-plane mode of aluminum nitride-actuated piezoelectric microcantilevers was carried out by using electrical and optical techniques. The top electrode of the cantilever was specifically designed to allow for an efficient electrical actuation of these in-plane modes. In order to confirm the in-plane nature of the modal vibration, the detection of the electrically induced movement was performed optically with the help of a stroboscopic microscope. In parallel, resonances were also measured electrically by means of an impedance analyzer. The quality factor and the resonant frequencies of the in-plane modes were estimated from the corresponding measurement data when applying both detection techniques. Our results show quality factor values as high as 3,000 for the first in-plane mode in air.     

Improved particle concentration by cascade AC electroosmotic flow

The importance of electrokinetics in microfluidic technology has been growing owing to its versatility and simplicity in fabrication, implementation, and handling. Alternating-current electroosmosis (ACEO), which is the motion of fluid due to the ion movement by an interaction between AC electric field and an electrical double layer on the electrode surface, has a potential for a particle concentration method to detecti rare samples flowing in a microchannel. This study investigates an improved ACEO-based particle concentration by cascade electrokinetic approach. Flow field induced by ACEO and accumulation behavior of particles were parametrically measured to discuss the concentrating mechanism. The accumulation of particles by ACEO can be explained by a balance between the attenuating electroosmotic flow to transport particles and the inherent diffusive motion of the particles, which is hindered due to the near-wall location. Although a parallel double-gap electrode geometry enables particles to be collected at the center of electrode very sharply, it has scattering zones with accumulated particles at sidewalls of the channel. This drawback can be overcome by applying sheath flow or introducing cascade electrode pattern upstream of the focusing zone. As a result, total concentration efficiency was 98.4 % for all the particles flowing in the cascade device. The resultant concentrated particles exist on the electrode surface within 5 μm, and three-dimensional concentration of particle with the concentration factor as large as 700 is possible using a monolithic channel, co-planar electrode, and sheathless solution feeding. This cascade electrokinetic method provides a new and effective preconcentrator for ultra-sensitive detection of rare samples.