共查询到19条相似文献,搜索用时 93 毫秒
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天然VE和植物甾醇的液相色谱分析 总被引:2,自引:0,他引:2
介绍了天然VE和植物甾醇的高效液相色谱分析方法。使用SY-8000系列仪器搭建等度或二元低压液相色谱系统,对样品组分进行分离和检测,取得了较好的结果。 相似文献
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Waters ACQUITY UPC~2仪器结构和性能特点 总被引:1,自引:0,他引:1
Waters超高效合相色谱(Ultra Performance Convergence Chromatography,UPC2)技术集合SFC和UPLCTM的技术优点。泵系统的传输性能精准(精度0.001mL/min);样品室温控4~40℃,应用nano阀技术的进样器可在0.1~50μL内调控,进样线性>0.999、进样交叉污染<0.005%;色谱柱管理器可容纳并自动切换6根色谱柱,色谱柱具有eCordTM、主动预加热器功能(温控精度±0.1℃);可连接PDA、ELSD以及质谱等检测器。结合亚2μm颗粒填料技术,UPC2系统在以下应用方面分析结果优异:手性化合物、脂质、异构体、天然产物提取物等复杂体系,正相HPLC取代技术,GC、反相HPLC的正交、互补技术。 相似文献
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Waters超高效合相色谱(Ultra Performance Convergence Chromatography,UPC2)技术集合SFC和UPLCTM的技术优点。泵系统的传输性能精准(精度0.001mL/min);样品室温控4-40℃,应用nano阀技术的进样器可在0.1-50μL内调控,进样线性〉0.999、进样交叉污染〈0.005%;色谱柱管理器可容纳并自动切换6根色谱柱,色谱柱具有eCord^TM、主动预加热器功能(温控精度±0.1℃);可连接PDA、ELSD以及质谱等检测器。结合亚2μm颗粒填料技术,UPC2系统在以下应用方面分析结果优异:手性化合物、脂质、异构体、天然产物提取物等复杂体系,正相HPLC取代技术,GC、反相HPLC的正交、互补技术。 相似文献
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一、前言高效液相色谱仪作为一种有效的分离分析工具,目前已在分析化学的各个领域得到了广泛应用。高效液相色谱仪也可以作为一种制备手段,把色谱柱分离了的各个组份有效地收集起来,得到高纯度的样品。样品的制备量(包括色谱纯样品的制备量),根据需要的不同而不等,可从微克数量级到近百克。少量制备的 相似文献
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一种新的半监督直推式支持向量机分类算法 总被引:2,自引:0,他引:2
传统的支持向量机(SVM)是一种有监督学习方法,需要大量有标记样本,然而有标记样本的数量十分有限且获得困难。因此,当存在海量的无标记样本时,如何有效地利用这些数据成为了机器学习面临的重要任务。研究提出了一种新的半监督直推式支持向量机分类算法,将半监督算法与支持向量机结合,在迭代算法中将无标签样本与有标签样本结合,逐渐得到更可信的分类超平面。理论分析和计算机仿真结果都表明,研究提出的样本能够有效地利用大量的无标签样本,并且无标签样本的加入能够有效地提高分类准确率。 相似文献
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模糊信息处理技术在故障诊断中的应用 总被引:1,自引:0,他引:1
本文介绍了模糊信息扩散理论及其在故障诊断中的应用,运用模糊信息扩散理论对某液压系统的振动参数进行信息扩散,得到七组典型状态样本,训练神经网络,实例证明:通过典型样本的建立,克服了大样本的矛盾性及学习时间长的缺点,该网络对系统状态的诊断效果很好。 相似文献
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A. V. Khakhalin A. V. Koroleva Ya. N. Shirshov 《Instruments and Experimental Techniques》2013,56(6):749-752
The created external thermostatting system of condensed samples in the cell of a MIDAC M4000 infrared Fourier spectrometer is described. A thermostabilized metal bar that was worked out by the authors is the basic element of the system. The system is intended for investigating the IR spectra of samples using the attenuated total reflectance method (ATR spectroscopy method). When the ATR method is used, the standard range of thermostatting of samples in this spectrometer model is from room temperature to 100°C with an accuracy of ±1°C. The desired temperature of the bar is set by the flow of a cooling fluid, which is supplied from an external thermostat, and it is registered with two thermometers (contact for the cell and infrared for a sample). The proposed approach allows samples to be thermostatted in the temperature range from ?12 to 80°C with an accuracy of ±0.5°C. 相似文献
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Xiao BP Reece CE Phillips HL Geng RL Wang H Marhauser F Kelley MJ 《The Review of scientific instruments》2011,82(5):056104
A radio frequency (RF) surface impedance characterization (SIC) system that uses a novel sapphire-loaded niobium cavity operating at 7.5 GHz has been developed as a tool to measure the RF surface impedance of flat superconducting material samples. The SIC system can presently make direct calorimetric RF surface impedance measurements on the central 0.8 cm(2) area of 5 cm diameter disk samples from 2 to 20 K exposed to RF magnetic fields up to 14 mT. To illustrate system utility, we present first measurement results for a bulk niobium sample. 相似文献
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This paper proposes the development of water sample classification and authentication, in real life which is based on machine learning algorithms. The proposed techniques used experimental measurements from a pulse voltametry method which is based on an electronic tongue (E-tongue) instrumentation system with silver and platinum electrodes. E-tongue include arrays of solid state ion sensors, transducers even of different types, data collectors and data analysis tools, all oriented to the classification of liquid samples and authentication of unknown liquid samples. The time series signal and the corresponding raw data represent the measurement from a multi-sensor system. The E-tongue system, implemented in a laboratory environment for 6 numbers of different ISI (Bureau of Indian standard) certified water samples (Aquafina, Bisleri, Kingfisher, Oasis, Dolphin, and McDowell) was the data source for developing two types of machine learning algorithms like classification and regression. A water data set consisting of 6 numbers of sample classes containing 4402 numbers of features were considered. A PCA (principal component analysis) based classification and authentication tool was developed in this study as the machine learning component of the E-tongue system. A proposed partial least squares (PLS) based classifier, which was dedicated as well; to authenticate a specific category of water sample evolved out as an integral part of the E-tongue instrumentation system. The developed PCA and PLS based E-tongue system emancipated an overall encouraging authentication percentage accuracy with their excellent performances for the aforesaid categories of water samples. 相似文献
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BacT/ALERT3D240是法国梅里埃公司在BacT/ALERT240基础上改良的具有世界领先水平的新一代血液培养系统,为了解改进后的优势,对我库用新系统检测1268份脐带血和用老系统检测1794份脐带血的结果进行比较分析,以传代培养及涂片镜检为金标准,二者的检测灵敏度、特异性、准确性分别为94.29%、100%、99.84%和90.48%、100%、99.78%,阳性检出时间分别为1.95h至6.0d和2.00h至6.5d。此外,新系统在硬件和软件方面具有明显优势,实用性更强。 相似文献