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多功能汽液平衡测定仪的研究 总被引:1,自引:0,他引:1
研制了一种多功能液平衡测定仪--CS-Ⅱ型VLE测定仪,阐述了该仪器的设计思想,该仪器兼有沸点仪和平衡釜的特点和功能,作为沸点仪,它具有泵结构搅拌器,可适用于拟静态法;作为平衡釜,它具有新型的汽液相取样结构和液相区冷却功能,可适用于安全互溶体系、部分互溶体系和高沸点差体系VLE的测定,本文给出了有关详细的实验考核结果。 相似文献
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肉类新鲜度快速检测方法 总被引:2,自引:0,他引:2
根据纳氏比色法测定氨氯的原理,设计制造了名为“肉类新鲜度快速检测仪”的仪器,应用此自制的仪器,一件肉类样品的检测仅需8min。试验表明,吸光度与NH4^+浓度在0~40mg/100g试样之间呈线性关系,其相关系数大于0.995,其检出限(3S/N)为0.5mg/100g。分析两件NH^+浓度不同的试样,测定结果的平均RSD(n=8)值为3.5% 相似文献
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设计中学化学实验用微型仪器是当前中学化学教学的一大任务,化学刊物已开始发表使用设计的微型仪器做实验的稿子,为了防止设计的微型仪器不符合实验的要求造成人力物力的浪费,在此提出中学化学实验用微型仪器应具备的条件供大家参考,并希望大家讨论。 相似文献
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建立黄曲霉毒素测定仪的校准方法。黄曲霉毒素测定仪校准项目主要包括仪器的动态基线漂移、长期基线噪声、线性相关系数、最小检测浓度、定性与定量重复性。选用C18色谱柱,以甲醇为流动相,流量为1.0 mL/min,其长期基线噪声不大于1500 counts/(30 min),动态基线漂移不大于5000 counts/h;当选用甲醇中黄曲霉毒素B1溶液标准物质,以乙腈-甲醇(1∶1)为流动相,仪器最小检测浓度不大于0.03 ng/mL,线性相关系数不小于0.998,定性重复性不大于1.0%,定量重复性不大于3.0%,仪器的计量性能正常。据此对影响仪器主要性能的各个参数进行全面评价,确认各项性能指标控制在合理范围内。该校准方法切实可行,可用于黄曲霉毒素测定仪的校准。 相似文献
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在一定条件下, 高分子及非挥发性有机化合物遵循一定的裂解规律, 即特定的样品能够产生特征的裂解产物及产物分布.裂解器-气相色谱质谱联用仪(pyrolyzer-gas chromatograph-mass spectrometer, Py-GCMS)将快速热解技术同气相色谱质谱联用技术结合, 作为研究木质生物质快速热解产物的重要仪器, 可定性、定量分析难挥发复杂基质成分.以CDS5200-7890A-5975C Py-GCMS为例, 从仪器的原理出发, 介绍Py-GCMS的使用技巧, 详细说明Py测试样品要求及操作注意事项.着重总结分享了仪器维护保养及故障处理经验, 指出规范有序及安全高效地运行Py-GCMS, 不仅可以保障科研活动, 在一定程度上也可延长仪器的使用寿命. 相似文献
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报道了一种新型仪器分析实验教学仪--“模块化自组装高效毛细管电泳教学仪”的研制及其在实验教学中的应用。对教学仪的结构设计、仪器组装和制作、工作原理以及教学应用实例进行了详细阐述和讨论。相比于目前教学中使用的商品化的高效毛细管电泳仪,该教学仪具有简单直观、模块化、自组装、价格低廉、便于推广的特点,能有效地将理论知识与对应的实践课程相结合,学生通过对仪器的动手组装深入了解其构造及功能,掌握分离原理和熟悉仪器操作,达到了提高教学效果和培养学生综合能力的目的。 相似文献
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Summary: A compact automated instrument has been developed for measuring the bivariate distribution by TREF fractionation and subsequent GPC analysis of the fractions in a single run. The configuration of this instrument and its operation principles are covered here. High resolution TREF fractionation of HDPE and fast methods with overlapped GPC injections are also discussed. Future developments, such the addition of comonomer or molar mass sensitive detectors, as well as operation in GPC – TREF mode for broad MWD resins are outlined. 相似文献
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等离子体质谱法测定大米、茶叶中痕量稀土元素 总被引:2,自引:0,他引:2
采用ICP—MS等离子体质谱法和使用HNO3+H2O2混酸体系高压密闭微波前处理样品联合技术,同时测定了大米、茶叶样品中15种稀土元素(La、Ce、Pr、Nd、Sm、Eu、Gd、Tb、Dy、Ho、Er、Tm、Yb、Lu、Y)含量。对消化条件、测定方法和等离子体质谱测定条件进行了优化选择,并进行了国家标准物质的对照分析质量验证。结果表明,检测方法的准确度达90%-110%,相对标准偏差(RSD)〈8%,仪器检出限为50—70ng/kg。该法快速灵敏,准确可靠,能够满足检测要求。 相似文献
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The Optical Technology Division of NIST has developed a new instrument for measuring ISO standard visual diffuse transmission densities using the diffuse influx mode. This instrument is used to calibrate both X-ray and photographic film step tablet Standard Reference Materials. The design, characterization, and operation of the instrument are detailed. The instrument was fully characterized both to verify compliance with the applicable international standards and to determine the combined uncertainty in transmission density associated with the calibrations. Results from comparisons with other laboratories are also presented. 相似文献
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Construction of an inexpensive surface plasmon resonance instrument for use in teaching and research
Barry K. Lavine David J. Westover Leah Oxenford Nikhil Mirjankar Necati Kaval 《Microchemical Journal》2007,86(2):147-155
The construction of an inexpensive SPR instrument that can be used for both teaching and research is described. Using a 2′ × 2′ optical table to construct this instrument allows both scientists and students full access to the operation of the spectrometer. Furthermore, the use of open platform instrumentation has the advantage of maintaining the focus on the relationship between emerging technology and analytical chemistry as well as allowing the user to modify the instrument to enhance the measurement process for a particular application. This is a change from the learning paradigm used in most research and teaching laboratories where commercial instrumentation is treated as a black box due to its complexity. Three studies, which were performed using this instrument, are presented to demonstrate the suitability of this instrument for both teaching and research. These studies include measuring the refractive index of alcohols, investigating the partitioning of ruthenium (II) trisbipyridine chloride into Nafion, and understanding the mechanism controlling metal ion adsorption by polyacrylamide hydrogels. 相似文献
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《中国化学快报》2023,34(4):107715
Liquid chromatography tandem mass spectrometry (LC-MS/MS) plays an important role in clinical diagnostics. Although LC-MS/MS is superior in terms of accurately quantifying molecules in complex matrices, instrument footprint, operation and maintenance complexity also hinder its expansion as the analytical technique of choice. In this study, a compact LC-MS instrument was developed, in which an assembled liquid chromatograph was coupled with a miniature ion trap mass spectrometer. The overall instrument has a footprint of 69 cm × 31 cm × 31 cm, and it requires no gas supply as well as minimum maintenance. Furthermore, the use of LC-MS is in accord with conventional clinical diagnostic protocols, and the choice of ion trap offers tandem MS performance. The results showed that the use of LC could improve both mixture analysis capability and detection sensitivity of the miniature mass spectrometer. After optimization, feasibility of this instrument in clinical practice was demonstrated by the quantitation of four widely used immunosuppressants in blood samples. Relatively good linearities were obtained, which spanned the reference ranges of effective therapeutic concentrations of each immunosuppressant. Intra-day and inter-day accuracy and precision of analytical method were also assessed. This work showed that a compact LC-MS instrument could be used in clinical diagnosis, either to replace conventional lab-scale instruments or to be used in POCT applications. 相似文献
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A pulsed laser photoacoustic (PA) instrument operating under visible and ultraviolet range was reported, which used a YAG pumped dye laser (width 8 ns, repetition rate 10 Hz) as the light source. Photoacoustic spectra of C2H2 overtone excitation and A1Au←X1Σ+g electronic transition were obtained using the instrument and the dependence of PA signal intensity on the sample pressure and the laser energy was measured. The application of pulsed PA to electronic transition was less reported before. Because of the simplification of its theoretical treatment and experimental operation, the pulsed PA instrument can replace resonant (or non-resonant) moderate cw PA instrument in almost all the cases except the ultra high-resolution spectroscopy. The difference between pulsed and cw moderate PA was also discussed in the text. 相似文献