海产品中多聚磷酸盐的离子色谱法测定

本文建立了一种采用去离子水提取，三氟乙酸作为蛋白沉淀剂对海产品样品进行前处理，采用淋洗液自动发生装置在线产生KOH进行梯度淋洗，抑制型电导离子色谱法，检测海产品样品中多聚磷酸盐的方法。本文亦比较讨论了不同沉淀剂对保留时间和加标回收率的影响。该方法具备抗干扰能力强，选择性好，灵敏度高，对环境友好等特点。实际样品检测结果令人满意。     

非抑制型排斥离子色谱法快速检测油田回注液的重碳酸盐

介绍了一种采用离子排斥机理，羧酸基阳离子交换色谱柱进行分离，非抑制型电导检测，稀释后直接进样快速测定油田回注液中重碳酸盐含量的方法。选择的色谱条件为：IonPac CS17羧酸基阳离子交换柱，去离子水等度淋洗，非抑制型电导检测。本方法用于快速分析油田回注液样品中的重碳酸盐，并获得了令人满意的结果，单个样品的分析时间低于10min。该方法具有选择性好，操作简单，适用性广，节省时间，对环境友好等特点，用于实际样品测定，所得结果令人满意。     

离子色谱法测定有机无机肥中无机阴离子含量

本文建立离子色谱法测定有机无机复混肥料中氯离子、亚硝酸根离子、硝酸根离子、硫酸根离子和磷酸根离子的方法,采用AS19阴离子交换色谱柱、KOH溶液作为流动相梯度淋洗、抑制型电导检测。该法具有良好的线性(相关系数为0.9990-0.9995)和重复性(相对标准偏差为0.37%-0.91%),回收率为91.7%-105.1%。该方法简便实用,用于实际样品分析,所得结果令人满意。     

离子色谱-荧光检测法测定氟哌酸、盐酸环丙沙星、 依诺沙星

本文利用离子色谱—荧光检测法研究同时分离分析多种喹诺酮类广谱抗菌药的方法。氟哌酸、盐酸环丙沙星、依诺沙星在流速为1ml/min,淋洗液为0.015mol/l的H2SO435%CH3OH的离子色谱仪能很好的分离。用激发波长为347nm,发射波长为420nm的荧光检测器进行检测。三者的检测限分别是0.05ppm,0.105ppm和0.08ppm。具有良好的重现性和线性关系。对药物样品与混合样品进行测定,结果令人满意。     

氯乙酸类化合物在离子色谱中保留时间机理探讨

本文采用抑制电导检测离子色谱分析的方法,对乙酸,一氯乙酸,二氯乙酸,三氯乙酸在不同组成和pH值的淋洗液下进行测定,定性的分析了淋洗液pH值,样品pKa值及其水合阴离子半径对保留时间的影响。     

高效液相色谱紫外检测法测定茶(药)用菊花的绿原酸含量

建立了高效液相色谱分离以及四波长紫外检测测定菊花中绿原酸的方法.以甲醇:磷酸二氢钠缓冲溶液(浓度为0.1mol/L)=40∶60(用磷酸调节pH值为2.7)为淋洗液进行分离,对230nm、254nm、275nm、327nm4个波长检测出的绿原酸信号加以比较进行定性定量.用该方法对菊花样品中的绿原酸进行测定,检出限为0.085mg/L,精密度低于5％,结果令人满意.实验证明,该方法准确、可行,可以很好地对菊花中的绿原酸进行定性定量研究.     

AQF-离子色谱联用技术检测1,4-丁炔二醇中全氯

介绍了一种全新的“油相”样品前处理仪器--自动快速燃烧炉（AQF）与离子色谱联用技术,测定1,4-丁炔二醇中全氯的方法.选择色谱条件为：AS14A离子色谱分离柱,碳酸钠/碳酸氢钠缓冲溶液等度淋洗,抑制型电导检测.样品经过AQF装置分段燃烧约10分钟后,在线进入离子色谱系统进行分析.该方法的检测限（S/N=3）为60 μ g/L,线性相关系数r=0.9997,RSD为2.9%,回收率为100-104%,具有灵敏度高,选择性好,操作简单,节省时间,对环境友好等特点,用于实际样品的检测,所得结果令人满意.     

两步梯度法分析酸雨中阴离子

本文使用戴安公司的ICS-1100型离子色谱仪,通过安装选配淋洗液选择阀(三通阀)实现系统在两种淋洗液之间的切换。即离子色谱系统的二元梯度淋洗。选用色谱条件:高容量IonPac AS19氢氧根体系阴离子交换色谱柱,抑制型电导检测。两种淋洗液浓度可根据不同样品类型和检测要求灵活选择。我们对模拟雨水样品中的常规阴离子和含溴酸盐样品分别进行了测试。实验结果证明,本法可实现NaOH淋洗液的二元梯度淋洗。常规离子检测重现性满足要求:峰面积相对标准偏差在0.2%以内。校准曲线线性99.8%以上,标准加入回收率为80%～110%。结合CRD200使用,可大大减轻切换淋洗液造成的基线漂移,并进一步改善系统重现性和精密度。该技术仅在原有流路的基础上增加了一路淋洗液,并未改变核心功能部件,操作简单且可重复性强。大大拓展了原有离子色谱仪的应用范围。     

离子色谱法对液体食物产品中的安息香酸盐的检测

介绍了一种简单的离子色谱方法,用来直接检测液态食品中的安息香酸盐.采用全新的ICS-3000型多功能离子色谱仪,淋洗液自动发生装置在线产生氢氧化钾淋洗液,配合高容量的IonPac AS18色谱柱使用,对标准溶液和多种基体的实际样品进行了检测.样品只需要进行稀释和超声脱气即可直接进样,具有操作方便、重现性好、灵敏度高等特点,用于实际样品的检测,加标回收率结果也较为理想.经合作实验室、美国FDA和美国戴安公司多方验证,该方法可作为标准方法进行推广.     

湿巾中荧光增白剂迁移量现场快速检测方法和仪器的研究

采用自制的前表面荧光光谱仪(FFFS),研究了湿巾中荧光增白剂迁移量现场快速定量检测方法,该方法具有无需化学前处理样品、仪器设备简单、检测速度快、全程检测时间只需十min、定量准确、实用性强等特点,对实际样品的检测结果令人满意。     

The processing of rotor startup signals based on empirical mode decomposition

In this paper, we applied empirical mode decomposition method to analyse rotor startup signals, which are non-stationary and contain a lot of additional information other than that from its stationary running signals. The methodology developed in this paper decomposes the original startup signals into intrinsic oscillation modes or intrinsic modes function (IMFs). Then, we obtained rotating frequency components for Bode diagrams plot by corresponding IMFs, according to the characteristics of rotor system. The method can obtain precise critical speed without complex hardware support. The low-frequency components were extracted from these IMFs in vertical and horizontal directions. Utilising these components, we constructed a drift locus of rotor revolution centre, which provides some significant information to fault diagnosis of rotating machinery. Also, we proved that empirical mode decomposition method is more precise than Fourier filter for the extraction of low-frequency component.     

香叶中挥发性组分的超临界萃取及气相色谱-质谱分析

用正交试验法研究超临界萃取香叶挥发性成分的条件，并用气相色谱-质谱联用技术分析了香叶挥发油的化学成分。结果显示萃取条件按对结果影响大小依次排列为：萃取压力、萃取温度、萃取时间,最佳萃取条件为萃取压力30 MPa、萃取温度40 ℃、萃取时间1 h。挥发油收率为2.6%,从中确认出47种化学成分，而用同时水蒸气蒸馏 溶剂萃取方法收率仅为0.8%，仅确认出30种挥发性成分。     

The performance of a new measuring method for three-dimensional ball motion in a ball-bearing

Recently, a new method for measuring ball motions three dimensionally was developed by one of the present authors and its principle was reported in the previous paper.Before its practical applications were examined, the calibration tests were carried out and the outputs obtained by this new method were compared with the values expected theoretically. By compensating for some undesirable effects, it was confirmed that the outputs were sufficient to analyse actual ball motions within an experimental error of 5%.In order to demonstrate its usefulness, an example of experimental results obtained by this new technique is shown.     

The press-brake bending of rigid/linear work-hardening plates

The analogy between the deformation of the rigid/linear work-hardening beam beyond yield and the linear elastic beam is successfully applied to analyse press-brake plate and sheet bending. Some of the results obtained cannot be obtained by using more elementary theories. Compared with an analysis by the finite element method[4], the solution in this paper not only needs much lesss computing storage and time, but also provides a clearer insight into the physical mechanisms which operate. The springback effect is considered.     

多种离子色谱法检测矿泉水中的硅酸盐

本文新开发出多种检测矿泉水中硅酸盐的离子色谱方法,包括等度非抑制型电导检测法、等度非抑制型紫外检测法和抑制型紫外检测法,并将三种方法与已有梯度非抑制型电导检测法进行了详尽的比较。文中三种新方法选取的色谱柱均为高容量选择性IonPac AS22色谱柱,配合使用IonPac AG14A保护柱,碳酸盐等度淋洗。几种方案各具特点,均可准确分析矿泉水中硅酸盐的含量,可按照实际情况灵活选用。后期配合Chromeleon 6.8色谱工作站的丰富功能,辅助完成数据处理工作,以得到满意结果     

直接煮沸和水浴浸提-电感耦合等离子体质谱法测定土壤中有效硼的对比研究

以玻璃器皿水直接煮沸 5 m in与塑料杯水浴 ( 1 0 0℃ )加热 65 min两种方法浸提土壤中的有效硼 ,采用电感耦合等离子体质谱法 ( ICP-MS)测定。两种浸提方法比较试验结果表明 :与常规的热水浸提法相比 ,塑料杯水浴法具有空白低 ,可以避免样品处理过程中的硼污染 ,条件易于控制 ,成本低的特点。由于水浴法温度低于常规的电热板煮沸法 ,其有效硼测定结果略低于采用煮沸法确定的标准值。两种方法经国家一级标准物质验证 ,测定值均在误差允许范围内 ,其测定值呈显著正相关 ( r=0 .988)。方法检出限为 0 .68ng/g(水浴法 )、8.2 2 ng/g(煮沸法 )。采用该方法测定了某硼矿区土壤样品中的有效硼     

小茴香中挥发油组分的微波辅助提取

A new method, non-polar solvent microwave-assisted extraction (NPSMAE)，was applied to extraction of essential oils from Foeniculum vulgare Mill.. By adding microwave absorption medium (carbonyl iron powders) into extraction system, the non- polar solvent (ether) was heated by CIP and the essential oil was obtained at high pressure. The constituents of essential oil obtained by NPSMAE was compared with that obtained by hydrodistillation (HD) by GC/MS analysis. The main volatile constituents in extracts obtained by different methods were similar, which indicated that NPSMAE was a feasible way to extract essential oil from dried plant materials. The NPSMAE took much less extraction time (5 min) than HD (180 min).     

Vector ARMAX modeling approach in multi-input modal analysis

This paper analyses multivariate time series using a parametric approach for the purpose of identification of modal parameters of mechanical structures. Because of computer capacity the multi-input/multi-output (MIMO) data were treated with the multi-input/single-output (MISO) consecutively. By noting that some of the modal parameters must have global characteristics regardless of measurement locations in theory, a MIMO modeling approach is taken to analyse a set of multiple-random excitation/multiple response measurements. The MISO approach is also applied to the same data and the results obtained by the two methods are compared. Two specific regression models for the MIMO and MISO approach are derived from the vector Autoregressive Moving Average model with exogenous variables (ARMAX) and the least squares method is applied iteratively for the parameter estimation. The modal parameters are derived from the parameters of the vector ARMAX based upon the principle of impulse response invariance. The procedures are used to analyse a set of simulation data of a three degree of freedom system.     

ANALYSIS OF CAPSAICIN AND DIHYDROCAPSAICIN IN HOT PEPPERS BY ULTRASOUND ASSISTED EXTRACTION FOLLOWED BY GAS CHROMATOGRAPHY–MASS SPECTROMETRY

A simple method for the analysis of capsaicin and dihydrocapsaicin in peppers by ultrasound assisted extraction (USAE) followed by gas chromatography–mass spectrometry (GC-MS) has been developed. USAE conditions were optimized by experimental design in order to maximize analyte extraction. A full factorial design involving extraction variables such as solvent (ethanol and water), extraction time (5–25 min), extraction temperature (25–50 °C), sample amount (0.25–0.5 g), and ultrasound amplitude (40–80%) was applied. The most significant conditions for capsaicinoid extraction by USAE were solvent type, extraction time, and sample amount. The obtained results were compared with other extraction methods: the official Soxhlet method and a previously reported solid phase microextraction method. Results showed that the extraction efficiency with the application of USAE (98%) was as good as that obtained with Soxhlet and the precision of recovery was less than 5%; in addition, the extraction time was decreased from 5 h to 25 min. The GC-MS analytical method was linear in the range 10–100 μg/mL for capsaicin and dihydrocpsaicin with correlation coefficient r = 0.998 and peak area variability of ～1% for both capsaicinoids. The method was applied to the analysis of 11 varieties of hot peppers cultivated in México. A large concentration range for capsaicin (101–6800 μg/g) and dihydrocapsaicin (110–2736 μg/g) was found in these pepper samples.