紫外可见反射光谱法快速鉴别复印纸

建立了鉴别纸张种类的新方法。采用紫外可见反射光谱对20种不同牌号的A4复印纸进行了快速检验,同时研究了复印纸热老化、紫外光老化和自然光老化的规律,并考察了打印、复印过程对测试结果的影响。方法可对不同厂家、不同牌号、相同厂家不同牌号复印纸的种类进行区分,具有快速、灵敏、准确、不损坏检材的特点,为纸张的相同性比对和同一认定提供了一种实用的检验方法。     

ICA方法与NIR技术用于药片中活性成分含量的测定

用独立分量分析(ICA)方法提取药片近红外光谱数据矩阵的独立成分和相应的混合矩阵, 再用BP神经网络对混合矩阵和药片中活性成分的浓度矩阵进行建模, 提出了新的药片活性成分含量测定的基于独立分量分析-神经网络回归(ICA-NNR)的近红外光谱分析方法. 通过分析独立分量数和网络中间隐层的神经元数对模型性能的影响, 分别建立三类药片定量分析的最优模型. 该方法用于实测的三类药片中活性成分含量的测定, 测试样品集的化学检测值与近红外预测值的相关系数分别达到0.962, 0.980及0.979. 结果表明, 基于ICA-NNR的近红外光谱分析方法对制药业的药片进行定量分析是可行的.     

红外反射光谱法在金属表面光洁度表征中的应用

本研究利用傅里叶变换红外反射光谱技术,通过对比不同光洁度的金属表面红外反射光谱图,建立了利用傅里叶变换红外反射光谱表征金属表面光洁度的方法,本文从红外反射光谱图4000cm-1～600cm-1、3400cm-1～2600cm-1波段的斜率及4000cm-1、3000cm-1、2000cm-1波数处的反射率两方面进行考察,结果表明,斜率和某一波数处的反射率均能用来表征金属表面的光洁度,且具有较高的准确性。     

蒿甲醚缓释片体外释放研究

目的:建立蒿甲醚缓释片体外释放的含量测定方法,并对其进行体外释放考察。方法:以释放介质作为酸消解溶剂,用酸消解间接紫外分光光度法测定片剂在释放过程中的累计百分释放度;浆法考察片剂的体外释放。结果:优选了最佳酸消解条件,并确定了片剂体外释放含量测定方法:蒿甲醚缓释片2h,5h,10h的体外累计百分释放度分别为25%,60%,85%;在诸多因素中离子强度是影响缓释片释放较灵敏的因素。结论:方法准确、快速、可行,适于体外释放实验样品量大的要求;体外实验表明蒿甲醚缓释片具有比普通片明显的缓释效果。     

基于贝叶斯决策的近红外光谱药片分类方法

针对药片近红外光谱法分类过程中校正集样本数量过少且各类样本数量不均导致分类误差问题,提出了基于贝叶斯决策的分类方法。本方法对校正集样本在各类中的先验概率密度和各类药片光谱的类条件概率密度进行了估计,利用贝叶斯全概率公式计算了待分类光谱分属于各类的后验概率,根据后验概率大小对药片分类。实验随机选取4类数量不等的西酞普兰药片70片,建立贝叶斯决策分类模型,对20片验证集药片进行分类,各类的分类灵敏度和特异度均达到了100%,对比判别最小二乘法的分类结果,验证了贝叶斯决策分类法能将样本及其近红外光谱的分布信息参与分类决策,提高了分类的准确性和适应性。     

蒿甲醚缓秋片体外释放研究

目的 建立蒿甲醚缓释片体外释放的含量测定方法，并对共进行体外释放考察。方法 以释放介质作为酸消解溶剂，用酸消解间接外分光光度法测定片剂在释放过程中累计百分释放度；浆法考察片剂的体外释放。结果 优选了最佳消解条件，并确定了片剂体外释放含量测定方法：蒿甲醚缓释片２ｈ，５ｈ，１０ｈ的体外累计百分释放度分别为２５％，６０％，８５％；在诸多因素中离子强度是影响缓释片释放较灵敏的因素。结论 方法准确、快速、可     

氯高铁血红素含量测定的不确定度分析

对UV法测定氯高铁血红素原料药含量的不确定度进行估算。通过建立UV法测定氯高铁血红素原料药含量的数学模型,找出影响不确定度的因素并对各个不确定度分量进行评估。计算各变量的不确定度,由此计算合成不确定度,最终给出测量结果的扩展不确定度和置信水平。建立的不确定度评估方法可用于UV法测定的氯高铁血红素原料药不确定度分析。     

超高压提取桑叶芦丁

考察了常温下超高压提取桑叶芦丁的提取工艺,观察了不同提取溶剂、提取压力、溶剂与原料比、提取时间及桑叶颗粒大小等因素对桑叶芦丁提取率的影响,并对提取工艺进行了优化。桑叶芦丁的最佳萃取条件为:70%乙醇水溶液为提取溶剂,提取压力为500MPa,提取时间为8min,桑叶颗粒大小为0.18～0.25mm,溶剂与原料比为20∶1,桑叶芦丁提取率达23.9mg/g。     

气相色谱法用于分枝杆菌脂肪酸组成与菌种鉴定的研究

采用非极性毛细管柱气相色谱法对３株分枝杆菌细胞脂肪酸化学组成进行了研究,得到特异性指纹识别图,并对７例临床分离的分枝杆菌进行了鉴别。结果表明,结核菌硬脂酸（ＴＳＡ）为分枝杆菌属的特征组分,其含量与其他中长链脂肪酸的百分组成随菌种不同而异。     

直接甲醇燃料电池催化活性层的优化

本文考察了直接甲醇燃料电池 (DMFC)不同催化剂载量的膜电极性能 .对催化剂层中Nafion含量进行优化 ,研究了Nafion含量对电池的阻抗的影响 .实验发现 :DMFC适宜的阳极Pt_Ru/C载量为Pt 4mg/cm2 、Nafion质量百分含量为 2 1.4 % ;高电流密度下 ,阴极Pt/C载量为Pt4mg/cm2 、Nafion质量百分含量为 2 1.4 %时 ,有较好的放电性能 ,继续增加Nafion含量 ,阴极的欧姆极化和浓差极化增大 ,电池性能下降     

Indirect Electrosorptive Detection via Kinetic Facilitation in Ion Chromatography

Abstract

A new technique based on electrosorption is presented for the determination of selected anions in ion chromatography. Unlike conventional methods, which are based on the measurement of nonfaradaic currents, the present method utilizes a kinetic facilitation imparted to the electroreduction of a cationic “adsorbate probe” by specifically adsorbed anions, and hence involves the measurement of faradaic currents. Amminated, transition-metal salts of Co(III) have been found most useful as adsorbate probes for this application. The current enhancement-analyte concentration response curves obtained were determined to be linear over a limited range at mercury, but show curvature at virtually all concentrations at silver. Detection limits for this technique are slightly higher than those realized using more conventional double-layer capacitance methods. A brief discussion of the future prospects for this new approach is given.     

单碱基多样性的非测序检测

单碱基多样性（SNP）是最常见的基因突变形式之一,经研究证明与很多疾病相关。虽然测序是检测SNP的重要方法,但其需要检测仪器,且检测时间较长,限制了其临床应用。本文综述了SNP的常见非测序分析方法。首先讨论了检测的热力学问题,并归纳了主要的检测策略：基于杂交的检测,基于链取代反应的检测和酶介导的检测。在三维均相检测方法中,主要介绍了不同信号开关策略,如荧光开关、酶识别开关和场效应开关。三维原位检测不仅能检测SNP,还能提供其细胞定位信息,在细胞异质性较高时更具优势。二维界面检测的识别反应速率和杂交效率受到一定影响,但界面检测能进一步减小干扰,亦便于实现高通量检测。以DNA正四面体探针界面为代表的改良界面具有优良的灵敏度和特异性。同时本文亦讨论了现有方法的局限性,并对SNP非测序检测研究进行展望。     

A 2D cadmium metal–organic framework: Synthesis,structure and luminescence sensing for chromate,permanganate, cupric,silver and ferric

A multi-responsive Cd metal–organic framework {[Cd (ttpe)(H₂O)(ip)]•4H₂O•DMAC}_n ( 1•4H ₂ O•DMAC ) was synthesized using hydrothermal method (ttpe = 1,1,2,2-tetra(4-(1H-1,2,4-triazol-1-yl)phenyl)ethylene, ip = isophthalate, DMAC = N,N-dimethylacetamide), and characterized. 1 exhibits a 2D (4,4) network. The luminescent sensing experimrnts showed that 1•4H ₂ O•DMAC as a new MOF luminescent sensor can detect Cr₂O₇²⁻, CrO₄²⁻, MnO₄⁻, Cu²⁺, Ag⁺ and Fe³⁺ in aqueous solution with simultaneously high efficiency and high sensitivity. The quenching constants K_sv for Cr₂O₇²⁻, CrO₄²⁻, MnO₄⁻, Cu²⁺, Ag⁺ and Fe³⁺ are 4.231 × 10⁴ M⁻¹, 2.471 × 10⁴ M⁻¹, 6.459 × 10³ M⁻¹, 7.617 × 10³ M⁻¹, 1.563 × 10⁴ M⁻¹ and 3.574 × 10⁴ M⁻¹, respectively. The detection limits are 0.094 μM for Cr₂O₇²⁻, 0.108 μM for CrO₄^{2 −} , 0.346 μM for MnO₄⁻, 0.302 μM for Cu²⁺, 0.221 μM for Ag ⁺ , and 0.100 μM for Fe³⁺. 1•4H ₂ O•DMAC exhibits high photocatalytic efficiency for degradation of methylene blue under visible light irradiation.     

Integration of Separation Capillary with a Au Film Electrode and an Etched Decoupler in Amperometric Capillary Electrophoresis

Introduced in this article is fabrication of an integrated capillary for the applications of electrochemical detection in capillary electrophoresis. The separation section, voltage decoupler, and working electrode were composed into a single section of capillary. The porous decoupler was constructed by HF etching till the thickness of the capillary wall less than 20 μm. The working electrode was prepared by sputtering Au-films on the outlet of the capillary. The integration of the separation capillary with a complete detection assembly improves the convenience for the routine application of electrochemical measurements in capillary electrophoresis. For a 100-μm-i.d. capillary, the theoretical plate number of catechol and the migration time reproducibility can reach 120,000 and 1.9% RSD, respectively. The linear range exceeds 3 order of magnitude and the detection limit is lower than 0.65 μM.     

Surface-enhanced Raman scattering for protein detection

Proteins are essential components of organisms and they participate in every process within cells. The key characteristic of proteins that allows their diverse functions is their ability to bind other molecules specifically and tightly. With the development of proteomics, exploring high-efficiency detection methods for large-scale proteins is increasingly important. In recent years, rapid development of surface-enhanced Raman scattering (SERS)-based biosensors leads to the SERS realm of applications from chemical analysis to nanostructure characterization and biomedical applications. For proteins, early studies focused on investigating SERS spectra of individual proteins, and the successful design of nanoparticle probes has promoted great progress of SERS-based immunoassays. In this review we outline the development of SERS-based methods for proteins with particular focus on our proposed protein-mediated SERS-active substrates and their applications in label-free and Raman dye-labeled protein detection. Figure Protein-mediated SERS-active substrates for protein detection     

Amperometric multidetection with composite enzyme electrodes

The use of composite biosensors for multianalyte detection strategies is discussed. Graphite–Teflon rigid composite biosensors offer the possibility of coimmobilization of several enzymes by simple physical inclusion in the bulk of the electrode matrix with no covalent linkages. A novel trienzyme graphite–Teflon–glucose oxidase (GOD)–alcohol oxidase (AOD)–peroxidase (HRP)–ferrocene bisosensor yielded amperometric steady-state currents similar to those obtained with graphite–Teflon–GOD–HRP–ferrocene and graphite–Teflon–AOD–HRP–ferrocene electrodes for the same concentration of glucose and ethanol, respectively. The performance of the trienzyme biosensor for multianalyte detection was evaluated with the simultaneous determination of glucose and ethanol after separation by HPLC, in samples of sweet wine. The simultaneous analysis of several analytes in the same sample should imply that, with an adequate dilution, the concentration levels of the analytes can be included within the ranges of linearity of the corresponding calibration plots. The use of two composite biosensors in a parallel configuration, so that different analytes can be simultaneously detected with no need of chromatographic separation, is also discussed. The usefulness of this approach was evaluated by the simultaneous analysis of glucose and ethanol in sweet wine, and of glucose and lactic acid in red wine.     

光照度探测器设计与精度校正

助航灯光系统为夜间或能见度较低环境下飞机的安全起降提供安全保障。快速准确地测量和判断其光强等级、光照射角等是否符合国际民用航空组织(ICAO)的标准,是保障机场安全运行的重要工作。本文设计了基于硅光电池的照度探测器,通过余弦校正器和不同滤光片的组合完成视见函数校正和照度探测的精度标定,实现了灯光的高速动态检测;完成了光照度探测器的线性标定和动态精度测量实验,照度测量误差率和动态测量误差均满足ICAO规定的要求;实现了助航灯光平行截面内光强的高速动态检测。     

Chromenone-rhodamine conjugate for naked eye detection of Al3+ and Hg2+ ions in semi aqueous medium

Chromenone-rhodamine conjugate 1 has been synthesized and its metal ion binding properties have been studied in CH₃CN/water (3:1, v/v; 10 mM HEPES buffer; pH = 6.85). Compound 1 senses multiple metal ions such as Al³⁺ and Hg²⁺ by exhibiting turn on fluorescence and color change (colorless to pink). Al³⁺ and Hg²⁺ ions have been distinguished with the aid of tetrabutylammonium iodide (TBAI). While in the presence of I^? the pink color of the 1.Hg²⁺ complex was completely discharged; under identical conditions the pink color of 1.Al³⁺ complex was retained.     

A review of reaction detection in HPLC

Summary In the past decade, reaction detection has rapidly gained importance as a means to improve the sensitivity and selectivity of detection in HPLC. Today, most attention is being paid to post-column reaction detection with final analysis via fluorescence monitoring. Novel developments involve the use of solid-phase reactors for reagent addition or catalysis (ion-exchange resins, immobilized enzymes), and the increasing use of systems based on peroxyoxalate chemiluminescence detection. The rapidly growing number of reported applications indicates that commercialization of reaction-detection equipment is urgently needed.