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31.
一种基于流动注射梯度技术识别异常峰及校正的方法   总被引:1,自引:0,他引:1  
范世华  方肇伦 《分析化学》2002,30(9):1038-1041
基于流动注射梯度信息提出了一种利用梯度比均值进行定量的校正方法。方法具有在线自动判别和修复异常峰并自行校正的功能,和通用的标准系列定量方法相比,两者测定精度相当。但本文提出的方法抗干扰能力明显优于后者,可适用于在线过程监测。  相似文献   
32.
Intracellular pH plays a significant role in various biological processes, including cell proliferation, apoptosis, metabolism, enzyme activity and homeostasis. In this work, a novel design strategy for the preparation of pH responsive carbon dots (CDs-pH) for ratiometric intracellular imaging was reported. By using SciFinder database, fluorescent CDs-pH with the required pKa value of 6.84 were rationally designed, which is vital important for precise sensing of intracellular pH. As a result, the synthesized CDs-pH demonstrated robust ability to test pH fluctuations within the physiological range of 5.4-7.4. The CDs-pH was further utilized for fluorescent ratiometric imaging of pH in living HeLa cells, effectively avoided the influence of autofluorescence from native cellular species. Moreover, real-time monitoring of intracellular pH fluctuation under heat shock was successfully realized. This SciFinder-guided design strategy is simple and flexible, which has a great potential to be used for the development of other types of CDs for various applications.  相似文献   
33.
环境水中化学需氧量的FI分光光度法自动在线检测   总被引:10,自引:0,他引:10  
本文将流动注射分光光度法用于环境废水中化学需氧量(COD)的自动在线检测,方法线性范围在0-100mg/L之间,相对标准偏差<2%以葡萄糖和苯二甲酸氢钾混合液制备标准溶液,对标准参考水样COD含量(Cr值)的测定结果表明两者有良好的相关性(R=0.9880)对环境水样中COD含量的动态变化连续10h模拟试验,自制的在线过滤装置稳定,未发生堵塞现象;该系统可以较好地跟踪水样中COD浓度的实际变化  相似文献   
34.
A simple high-performance liquid chromatographic method was developed for the simultaneous determination of the therapeutic levels of acyclovir and ganciclovir in human plasma. After precipitation of plasma proteins with 6% perchloric acid, acyclovir and ganciclovir were simultaneously determined by reversed-phase chromatography with spectophotometric detection at 254 nm. The peak heights for acyclovir and ganciclovir were linearly related to their concentrations ranging from 0.063 to 2.080 micro g/mL. The recovery was 100.48-102.84% for acyclovir and 99.26-103.07% for ganciclovir. The intra- and inter-day relative standard deviation values were in the range 0.186-8.703% for acyclovir and 0.137-6.424% for ganciclovir. The detection limits for both compounds were 0.01 micro g/mL determined as the signal-to-noise ratio of 3. The present method is applicable to therapeutic monitoring during antiviral medication.  相似文献   
35.
利用商品化ITO玻璃导电层的温阻效应, 无需任何微加工手段, 实现了自加热和传感的芯片温度自动程序控制, 最大程度地减小了传感滞后对温度控制稳定性的影响, 温度控制的稳定性达到了0.2 ℃, 升温速度最快可达20 ℃/s以上, 在冷却风扇辅助下降温速度最快达到了8 ℃/s. 芯片温控单元的引线从传统的两对(一对用于传感, 一对用于加热)减少为一对. 通过在该芯片上直接构建多个开放微池反应器的方法成功地实现了λDNA 157 bp片段的并行扩增. 将该芯片置于倒置荧光显微镜样品台上, 以蓝色(575 nm)发光二极管为光源, 以光电倍增管为检测手段检测了dsDNA和SYBR Green Ⅰ嵌合物的荧光强度随温度的实时变化曲线.  相似文献   
36.
科学仪器工作状态监测装置的设计与实现   总被引:1,自引:0,他引:1  
建立了支持网络通讯的科学仪器工作状态监测装置。该检测装置以单片机系统为核心,运用信号检测技术获取仪器的工作状态信息,实现有效机时的记录。基于自制编码表对数据进行BASE64编码,保证了记录信息的安全;支持嵌入式互联网技术将被监测仪器的实时状态上传到远程服务器,实现大型科学仪器的网络化监测。  相似文献   
37.
环境样品分析   总被引:5,自引:0,他引:5  
本文是“分析试验室”定期评述“环境样品分析”的第8篇综述。它全面评述了2004年1月至2005年12月间我国环境样品分析各个方面的进展,主要内容包括:概述,大气、水体、土壤和沉积物、生物样品分析,质量控制和质量保证等。引用参考文献967篇。  相似文献   
38.
工业废水中微量铜(Ⅱ)和氰化物的流动注射光度分析   总被引:2,自引:0,他引:2  
王鹏  贾东玲 《分析化学》1995,23(1):36-38
采用FIA技术,以光度比色法为基础,建立了工业废水中微量Cu^2+和CN^-的顺序自动分析方法和装置。其对二种离子的测定频率为60样/h,相对标准偏差<1.0%,工作曲线的r值≥0.999,各项分析技术指标均优于手工法操作。  相似文献   
39.
Yellow poplar wood sawdust consists of 41% cellulose and 19% hemicellulose. The goal of pressure cooking this material in water is to hydrate the more chemically resistive regions of cellulose in order to enhance enzymatic conversion to glucose. Pretreatment can generate organic acids through acid-catalyzed degradation of monosaccharides formed because of acids released from the biomass material or the inherent acidity of the water at temperatures above 160°C. The resulting acids will further promote the acid-catalyzed degradation of monomers that cause both a reduction in the yield and the formation of fermentation inhibitors such as hydroxymethyl furfural and furfural. A continuous pH-monitoring system was developed to help characterize the trends in pH during pretreatment and to assist in the development of a base (2.0 M KOH) addition profile to help keep the pH within a specified range in order to reduce any catalytic degradation and the formation of any monosac-charide degradation products during pretreatment. The results of this work are discussed.  相似文献   
40.
Preservation of sensitive CRMs and monitoring their stability at IRMM   总被引:1,自引:0,他引:1  
Over the years, the nature of CRMs has changed considerably. Recently, more and more CRMs have been certified in their "natural" form, that is processed as little as possible, with analytes at their natural concentration level. This and the trend towards certified properties other than the concentrations of clearly defined molecules/elements have made guaranteeing stability of CRMs and estimating a shelf life an even more important issue for reference material producers than it has been before. One way to meet this challenge is to take more care in processing, storage and dispatch of CRMs. At IRMM, approximately 20 % of the RMs are stored at –20 °C or below and about 10% require cooled transportation. In addition, increased efforts for assessing stability are needed. Shelf lives are estimated using addition of an uncertainty component based on real-temperature stability studies rather than by accelerated stability studies. These pre-certification efforts are complemented by a stability-monitoring program, which at IRMM includes 80 % of the non-nuclear and non-isotopic materials. Although the costs for these efforts are high in absolute terms, they are only a minor and indispensable contribution to the total costs of CRM production.  相似文献   
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