谷物干燥机的温度巡检单元

介绍了谷物烘干机温度巡检单元的系统工作过程、性能、硬件构成、工作原理及系统软件。该文通过对谷物干燥机内谷物温度信号的巡回检测，根据系统硬件及现场实际需要，并根据温度量与粮电机转速之间的关系所建立的数学模型利用8032丰富的口资源，从而实现了谷物干燥过程的温度测量、通信、数据的转换及数据显示等。     

XPS analysis of bio‐organic systems

A survey of the literature is made for the XPS analysis of food products (mainly spray‐dried powders, which reveal a considerable surface enrichment in lipids) and of microorganisms and related systems (extracellular polymer substances and biofilms). This survey is used as a background for discussions and recommendations regarding methodology. Sample preparation methods reviewed are freeze drying, analysis of frozen hydrated specimens and adsorption of surface‐active biocompounds on model substrates. Peak decomposition is a way to increase the wealth of information provided by the XPS spectra. It should be performed after a check that sample charge stabilization is satisfactory. Moreover, ensuring the precision needed to make comparisons within sets of samples may involve a trade‐off between imposing constraints and generating information. The examination of correlations between spectral data in the light of chemical guidelines is useful to validate or improve peak decomposition and component assignment, and may also upgrade the chemical information regarding speciation. Further upgrading may be achieved by expressing marker XPS data in terms of concentrations of compounds of interest. Different methods of computation are discussed, providing a composition in terms of ingredients, classes of biochemical compounds, or various organic and inorganic compounds. As an alternative or complement to this deterministic approach, multivariate analysis of suitable spectral windows provides spectral components, which may be used for comparing samples, and which may have a direct chemical relevance or be used to identify features of interest. Copyright © 2011 John Wiley & Sons, Ltd.     

Preparation of Copper Chromite by Vaccum Freezing Drying Method and Its Catalytic Activity for Sulfuric Acid Decomposition

Iodine sulfur (IS) process is one of the most promising routes for massive and CO₂‐free hydrogen production. Among the three reactions IS process composed, decomposition of sulfuric acid is the most energy intensive step and has to be conducted in the presence of catalyst. In this work, copper chromite (CuCr₂O₄) was prepared, characterized, and used as the catalyst for sulfuric acid decomposition reaction. The co‐precipitation preparation method of CuCr₂O₄ which featured in vacuum freezing drying (VFD), was applied, and the main factors which influence the structure of CuCr₂O₄ such as pH values of the co‐precipitation solution and calcination temperature were investigated. Results showed that pH value affected the size of copper chromite granule, when pH was between 7 and 8, the size of prepared CuCr₂O₄ was in nanometer scale. Calcination temperature influenced the purity of the crystal. The samples were characterized by XRD, TEM and BET. The catalytic activity of CuCr₂O₄ prepared by VFD was evaluated and compared with CuCr₂O₄ prepared by usual co‐precipitation method and Pt/Al₂O₃. Results showed that the activity of CuCr₂O₄ was close to that of Pt catalyst, but apparently higher than that of CuCr₂O₄ prepared by usual method. In addition, it presents good stability in the 70 h test. Therefore, it was promising to be used in the sulfuric acid decomposition step of IS process.     

Simulation of dynamic speckle sequences and its application to the analysis of transient processes

Dynamic speckle has been used in recent years to analyse several transient processes that are produced in industrial and biological applications. We present here a numerical simulation to generate a temporal sequence of dynamic speckle patterns which is based on a model used for speckle formation by the superposition of waves from discrete scattering centres. It is demonstrated that the first and second statistics of the intensity of each speckle image, the time history of the speckle pattern, the temporal evolution of the correlation coefficient, and the power spectral density of the intensity generated by the proposed model reproduce quite well those obtained from experimentally recorded data. The process of a fast drying paint is presented as an example of the application of the proposed numerical model.     

Monitoring of Paint Drying Process by Digital Speckle Correlation

The state of drying paint is monitored from the dynamic behaviors of the speckle pattern arising from laser illumination of the region inspected. Temporal variation of the peak height of the cross-correlation function between successive frames taken with a fixed interval is plotted until the peak maintains a stationary maximum value. We used a speckle pattern in the diffraction field for monitoring of a single region and that in the image field for simultaneous monitoring of various regions. Both the normal and the phase-only algorithms were compared for cross-correlation computation. The former showed more distinct variation of peak height.     

Comparison of Drying Procedures for the Preparation of Alumina Powders with the System Al-Alkoxide/Tertiary Butanol/Water

Two series of alumina gel precursors, obtained from Al sec-butylate, ASB, or Al tert-butylate, ATB, dissolved in tertiary butanol, TB, have been dried according to five procedures, in order to compare their efficiency and the consequences they may have on the structure of the final product. They consist of lyophilization (or freezedrying), evacuation at room temperature (with or without ageing of the gel), drying in an oven at atmospheric pressure, or under hypercritical conditions. Chemical analysis, X-Ray diffraction and spectroscopic characterizations (FTIR and laser Raman) allow the identification of the phases present. The temperature of the drying step, as well as the nature of the alkoxide percursor, considerably affect the final dried products.     

膨润土粉碎—气流干燥技术研究

本文对粉碎气流干燥的原理、特点和设计原则进行了分析.通过试验测定了小颗粒膨润土在气流干燥管内的体积传热系数,为膨润土的粉碎——气流干燥器设计提供了依据.     

真空冷冻干燥设备的先进控制系统

对应用于宇航，军事，医药，营养保健食品等领域的真空冷冻干燥设备ＺＬＧ－３０等，用ＯＭＲＯＮ ＰＬＣ／４０Ｐ及单片机８０３２／ＥＵ８１８Ｐ１５构成手动，自动控制系统进行了硬件配置及软件设计；并针对不同冻干物料的工艺要求，采取ＤＲＡ算法和临界比例法两种自适应，自整定控制方法，解决了被控对象主控参数－温度的滞后等问题，实现稳定，可靠的自动化冻干过程。     

酸溶性钛渣的干燥特性及其影响因素

以氯化法生产钛白粉的主要原料酸溶性钛渣中的水分为研究对象,对酸溶性钛渣的常规干燥特性及影响因素进行了研究。通过研究酸溶性钛渣在温度变化、样品质量变化、以及初始含水量变化的条件下,获得干燥过程中的水分迁移行为,从而揭示酸溶性钛渣干燥过程的基本规律,探明酸溶性钛渣内部的传质机理。通过实验研究和理论探讨,为干燥冶金、化工原料的工业化应用和推广提供实验依据和理论基础。     

国内外蓝莓加工技术与功能性成分研究进展

蓝莓是一种越橘属浆果,除含有基础营养物质,还富含花青素、类黄酮等功能性成分,具有抗炎、抗癌、清除自由基、保护视力等功效。然而,新鲜的蓝莓易腐烂且贮藏和运输性能差,故需要进一步深加工,同时,蓝莓良好的健康属性使消费者对蓝莓加工产品的需求日益增加,应用可更好保留功能成分的先进加工技术已成为蓝莓加工产业发展的重要驱动力。阐述了近年蓝莓果汁、蓝莓果酒、蓝莓干燥等加工技术与功能性成分提取技术的研究进展,以期为蓝莓深加工产业提供理论依据。