连续流动法测定烟草水溶性糖的影响因素

为提高RFA-300连续流动分析仪测定烟草及烟草制品中水溶性糖含量的准确性.依据行业标准YC/ T159—2002对各种影响因素进行了考察,发现标准样品的种类、纯度及反应时间是主要影响因素,并根据试验结果和测试原理的要求对仪器管路进行了适当的加长。确定了以葡萄糖为标样.采用校正标样和加长仪器管路的连续流动法测定烟草制品中的水溶性糖。结果表明,改进后方法的回收率为98.8%-107.9%,变异系数为1.63%. 测定结果与芒森·沃克法的基本一致。     

连续流动分析法在葡萄酒总糖检测中的应用

采用连续流动分析法对不同类型的葡萄酒中的总糖进行了检测,并对连续流动法与费林法测定葡萄酒中的总糖结果进行比较分析,结果显示,两种检测方法的结果精密度和重现性没有差异。日常使用和检测结果数据显示,连续流动分析法测定葡萄酒中的总糖操作简单、自动化程度高,且检测结果准确度可靠、精密度高和重现性完全符合实验室质量控制规范的要求,可以广泛应用于葡萄酒中总糖含量的测定。     

层次分析法在烟草绩效考核指标权重确定中的应用

为了更好地实现烟草行业经济效益与社会效益目标,烟草公司必须建立行之有效且具备可操作性的绩效考核体系。而在绩效考核中各个指标的选取和指标的权重显得非常重要。本文针对烟草绩效考核,用层次分析法(AHP)对绩效考核的权重做了实证的研究。结果表明烟草中的绩效考核的指标中销售量、库存控制量和采购计划比的指标占了重要的比重。     

连续流动法测定烟草中水溶性总糖和还原糖的不确定度评定

依据JJF 1059. 1-2012《测量不确定度评定与表示》对连续流动法测定烟草样品中水溶性总糖、还原糖含量的不确定度进行评定,通过分析得出,测量重复性、样品前处理、标准溶液制备、标准曲线拟合、连续流动分析仪测量重复性是不确定度的主要来源。分析结果表明,当烟草样品中水溶性总糖为20. 4%时,扩展不确定度为0. 69%,k=2;还原糖含量为18. 4%,扩展不确定度为0. 77%,k=2。     

天然香料在烟草中的应用研究进展

本文综述了长白山地区天然植物精油资源及其在卷烟工业中的应用情况。并针对目前烟草工业对天然香料研究的需求情况,指出应在开发新的天然烟用香料资源、进一步优化天然香料的提取工艺、加强天然香料的生物活性在卷烟生产过程中的辅助作用的研究等三方面加强研究工作,同时对长白山地区丰富的植物精油资源的开发利用提出见解。     

连续流动法测定香料烟氯测量不确定度评定

为评定连续流动法香料烟氯的测量不确定度,对连续流动法测定氯的过程进行分析,得到简化的连续流动法香料烟氯的测定因果关系图,建立测量不确定度评定的数学模型,确定其测量不确定度的主要来源为样品的水分、连续流动分析仪测定的样品浓度和测量重复性。通过对测量不确定度进行评定,得出连续流动法香料烟氯测量结果的标准不确定度为0.04%,扩展不确定度为0.08%(α=0.05,k=2)。     

因子分析法在道路交通噪声分析中的应用

道路交通噪声的影响因素很多,而且这些因素互有联系且互相影响,以往一般都采用回归分析法来研究各因素对道路交通噪声的影响情况,但它很难从整体上反映出各因素对道路交通噪声的影响及各因素之间的内在关系,难于找出其主要矛盾.在道路交通噪声分析中应用因子分析法能方便地分析出影响道路交通噪声的各因素之间的关系,并从中找出最基本的影响因素,我们在珠海特区环境噪声现状调查中分析道路交通噪声时应用了因子分析方法取得了较好的效果.     

论网络营销在烟草营销中的应用

网络营销作为一种新的营销方式,给企业发展带来了新的机遇与挑战。本文分析了烟草行业开展网络营销的现实意义,并提出了实施对策。     

监控管理系统在烟草加工中的应用

我国的烟草行业正在利用烟草系统进行中式卷烟加工,至此,烟草行业正在摆脱以往粗放型注重外在指标(填充值、水份控制等)的质量管理模式转变为重视内在品质(烟草香气香量、口感吸味等)的质量管理模式,外在指标的质量管理模式向注重烟草香气香量、口感吸味等内在烟草品质的转变。在转变的过程中,进行技术改造是不可或缺的,重视生产管理也成为烟草行业的共识。进行技术升级和改造的过程中,将监控管理系统应用于烟草加工过程中,对此进行评论。     

数学建模在烟草制丝生产中的应用

以二贮后烟梗水分为因变量,以室内温度、室内湿度、刮板回潮出口温度值、刮板回潮出口水分值为自变量,应用多元回归分析,较为准确地估测烟梗在平衡过程后的水分值。     

电机定子铁芯振动特性分析的一种解析方法

随着新能源汽车的发展,用户对电机噪声的要求日趋严格,噪声振动分析已经成为电机开发中的重要内容.定子的电磁振动是电机的主要噪声源,由于电机定子的复杂结构,目前常用有限元方法建模分析定子铁芯的振动特性,耗时太长,不能满足定子优化设计的振动噪声特性快速计算要求.提出了一种解析方法用于计算定子铁芯的振动特性.采用厚壳-梁耦合结...     

Advanced process design and understanding of continuous twin-screw granulation via implementation of in-line process analytical technologies

Process analytical technologies (PAT) are identified as an essential element in the Quality by Design framework, providing the cornerstone to implement continuous pharmaceutical manufacturing. This study is concerned with employing three in-line PATs: Eyecon? 3D imaging system, Near-infrared spectroscopy (NIRS) and Raman spectroscopy (RS), in a continuous twin-screw granulation process to enable real-time monitoring and prediction of critical quality attributes of granules. The Thermo Scientific? Pharma 11 twin-screw granulator was used to manufacture granules from a low-dose formulation with caffeine anhydrous as the model drug. A 30-run full factorial design including three critical process parameters (liquid to solid ratio, barrel temperature and throughput) was conducted to evaluate the performance of each analytical tool. Eyecon? successfully captured the granule size and shape variation from different experimental conditions and demonstrated sufficient sensitivity to the fluctuation of size parameter D10 in the presence of process perturbations. The partial least square regression (PLSR) models developed using NIRS showed small relative standard error of prediction values (less than 5%) for most granule physical properties. In contrast, the RS-based PLSR models revealed higher prediction errors towards granule drug concentration, potentially due to the inhomogeneous premixing of raw materials during calibration model development.     

光度比浊法测定烟草中硫酸根的含量

在丙二醇介质中,基于硫酸根离子与钡离子形成稳定的胶体沉淀,建立了光度比浊法测定烟草中硫酸根含量的分析方法。硫酸根浓度在0.0-60.0μg/mL范围内符合比耳定律,相关系数0.9992。用于测定烟草样品中的硫酸根含量,回收率范围95.8%-104.9%;变异系数1.7%(n=10)。样品测定结果与重量法基本一致,相对误差小于4.0%。方法操作简便、准确、快捷,具有实用价值。     

Determination of trace lead in water samples by continuous flow microextraction combined with graphite furnace atomic absorption spectrometry

A new method of continuous flow microextraction (CFME) combined with graphite furnace atomic absorption spectrometry (GFAAS) was proposed for the determination of trace lead in water samples. A drop of 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (PMBP) dissolved in benzene is injected into a glass chamber by a microsyringe and held at the outlet tip of a PTFE connecting tube, the sample solution flows right through the tube and the glass chamber, the solvent drop interacts continuously with the sample solution, and the analyte was extracted into the drop and concentrated. After extracting for a period of time, the drop was retracted into the microsyringe and directly injected into graphite furnace for determination of Pb. Several factors affecting the extraction efficiency, such as solution pH, sample flow rate, drop volume and extraction time, were optimized. Under the optimized conditions, a concentration factor of 45 was achieved, and the detection limits for Pb were 12 pg mL(-1). The relative standard deviation for six replicate analyses of 10 ng mL(-1) Pb was 6.8%. The proposed method was applied to determine of trace Pb in water samples with satisfactory results.     

Implementation of a symmetric boundary element method in transient heat conduction with semi‐analytical integrations

A time‐convolutive variational hypersingular integral formulation of transient heat conduction over a 2‐D homogeneous domain is considered. The adopted discretization leads to a linear equation system, whose coefficient matrix is symmetric, and is generated by double integrations in space and time. Assuming polynomial shape functions for the boundary unknowns, a set of compact formulae for the analytical time integrations is established. The spatial integrations are performed numerically using very efficient formulae just recently proposed. The competitiveness from the computational point of view of the symmetric boundary integral equation approach proposed herein is investigated on the basis of an original computer implementation. Copyright © 1999 John Wiley & Sons, Ltd.     

Micromechanic modeling and analysis of unsteady-state granular flow in a cylindrical hopper

This paper presents a numerical study of the micro- and macro-dynamic behavior of the unsteady-state granular flow in a cylindrical hopper with flat bottom by means of a modified discrete-element method (DEM) and an averaging method. The results show that the trends of the distributions of the microscopic properties such as the velocity and forces, and the macroscopic properties such as the velocity, mass density, stress and couple stress of the unsteady-state hopper flow are similar to those of steady-state hopper flow, and do not change much with the discharge of particles. However, the magnitudes of the macroscopic properties in different regions have different rates of variation. In particular, the magnitudes of the two normal stresses vary little with time in the orifice region, but decrease in other regions. The magnitude of the shear stress decreases with time when far from the bottom wall and central axis of the hopper. The results also indicate that DEM can capture the key features of the granular flow, and facilitated with a proper averaging method, can also generate information helpful to the test and development of an appropriate continuum model for granular flow.     

Micromechanic modeling and analysis of unsteady-state granular flow in a cylindrical hopper

This paper presents a numerical study of the micro- and macro-dynamic behavior of the unsteady-state granular flow in a cylindrical hopper with flat bottom by means of a modified discrete-element method (DEM) and an averaging method. The results show that the trends of the distributions of the microscopic properties such as the velocity and forces, and the macroscopic properties such as the velocity, mass density, stress and couple stress of the unsteady-state hopper flow are similar to those of steady-state hopper flow, and do not change much with the discharge of particles. However, the magnitudes of the macroscopic properties in different regions have different rates of variation. In particular, the magnitudes of the two normal stresses vary little with time in the orifice region, but decrease in other regions. The magnitude of the shear stress decreases with time when far from the bottom wall and central axis of the hopper. The results also indicate that DEM can capture the key features of the granular flow, and facilitated with a proper averaging method, can also generate information helpful to the test and development of an appropriate continuum model for granular flow.     

连续流动分析仪在石化水质分析中的应用

本文应用连续流动注射分析仪(FIA),成功地实现了一次进样同时完成水质中挥发酚和氰化物、硫化物和总氮的测定[1,2]。分析结果准确、可靠,大大缩短了分析时间,加标回收率在95%--105%之间,相关系数均大于0.9995。并与传统的分光光度法进行了比较,在保证分析方法准确度的前提下,FIA法能提高检测灵敏度和检测速率,此方法简单、快速,适合于批量分析。