气压传动与控制在电子专用设备上的应用

气压传动与控制已成为电子专用设备研制过程中一项不可缺少的内容 ,必须进行合理的气动系统设计及其控制 ,选择相应的气动元件以满足设备的功能要求。概述了气压传动与控制在电子专用设备上的应用。     

Effect of thermal and mechanical factors on rheological properties of high performance inulin gels and spreads

The aim of this study was analysis of a number of factors affecting the rheological properties of high performance inulin gels and spreads in comparison with commercial products. Inulin gels (20%, 25%, 30%), commercial and inulin model spread (20% canola oil, 20% inulin, 3% emulsifier) were analysed. Inulin particles in water environment absorbed water which caused an increase in viscosity of the inulin suspensions. Different temperatures of preparation, cooling rates and viscosity increase which appeared during the stirring of inulin suspensions did not significantly change the rheological parameters of the final gels in contrast to heating rates (p ? 0.05). In spite of rigid laboratory conditions high standard deviation for hardness and apparent viscosity showed how difficult the process of an inulin crystallization is to control. Rheological properties of inulin model spread exhibited thixotropic and shear thinning behaviour which made it similar to commercial spread. The applied structure destruction step in the manufacturing process should be applied to make inulin model spread comparable to commercial spreads.     

Properties of Dried and Intermediate Moisture Honey Products: A Review

This review discusses the processing techniques proposed for the production of dried and intermediate moisture honey products, as well as their properties. Stickiness is the major problem in the drying of sugar rich products like honey, that depend on the type of sugar and temperature of operation, which are related to the glass transition temperature. Some additives are usually added to the sugary feed to increase the glass transition temperature and concurrently the sticky point temperature. In the case of honey-fruit spreads, nutritional and sensory characteristics can be enhanced by replacing part of sugar with honey. Co-crystallization of honey with sucrose could be used to preserve the honey flavor. These diversified honey products provide better taste and nutrition to the consumer besides enhancing the utilization of honey.     

Centrifugal Slump Test to Measure Yield Stress

ABSTRACT: The performance of a centrifugal viscometer (a new concept) was tested for its ability to accurately predict the yield stresses of semisolid foodstuffs. This instrument is based on the traditional slump test concept, but utilizes centrifugal force rather than gravitational force to cause deformation. Using dimensional analysis, there was a general agreement between the theoretical approximation of the yield stress, and experimental data generated using the vane method.     

An algorithm for segmentation of metaphase spreads

An algorithm is proposed for locating chromosomes in photomicrographs of metaphase spreads. The algorithm resembles closely the method used by human operators to search microscopic fields. The algorithm was specially programmed to be used with small scale computers.     

Effect of κ-carrageenan on rheological properties, microstructure, texture and oxidative stability of water-in-oil spreads

The effect of κ-carrageenan concentration (0-7.5 g kg⁻¹) on the rheology, microstructure, texture and oxidative stability of water-in-oil (W/O) spreads (600 g fat kg⁻¹ emulsion) was examined over 60 days storage time. Results showed that increasing the κ-carrageenan concentration to 7.5 g kg⁻¹ significantly increased the viscosity of the aqueous phase (to 42.7 mPa s at 60 °C) resulting in gelation of the aqueous phase on cooling. The microstructure of the spreads was disrupted by higher levels of κ-carrageenan, resulting in a less homogeneous distribution of the aqueous phase. Melt temperature (where tan δ > 1) decreased significantly from 62 to 56.2 °C with increasing κ-carrageenan concentration from 0 to 7.5 g kg⁻¹. The firmness and the G′ at 6 °C for all samples were significantly increased after 60 days storage with only small effects due to κ-carrageenan levels. Oxidation of the fat phase was evident by the significant increases in peroxide values of all spreads on storage, with κ-carrageenan exhibiting no antioxidant behaviour. While increased κ-carrageenan levels modified the microstructure of W/O spreads in terms of the droplet size of the aqueous phase and its distribution few changes were evident in the continuous fat phase.     

土工布在旧水泥混凝土路面改造中的应用

结合广州南沙开发区金岭路的改造工程实践,对土工布在旧水泥混凝土路面沥青加铺层防止反射裂缝工程中的一些作用进行探讨     

Geometrical isomers of linolenic acid in low-calorie spreads marketed in France

The fatty acid compositions of 20 samples of low-calorie spreads marketed in France have been examined by gasliquid chromatography (GLC) of their isopropyl esters on a fused silica capillary column coated with 100% cyanopropyl polysiloxane. Spreads containing linolenic acid at a level of 2.3% or higher (5 out of the 20 samples under study) also containtrans- 18:3 isomers. These were identified, after fractionation of their isopropyl esters by thin-layer chromatography (TLC) on silica-gel plates impregnated with AgNO₃, by GLC on two capillary columns of different polarities and comparison of their equivalent chain lengths with those of authentic standards. Identifications were supported by GLC/mass spectrometry of the dimethyl esters resulting from ozonolysis in BF₃/methanol of the monoenes isolated by AgNO₃-TLC after hydrazine reduction of 18:3 isomers. 9c,12c,15t-18:3 and 9t,12c,15c-18:3 were found to be the most abundant 18:3 isomers in the spreads, with small amounts of 9c,12t,15c-18:3. These isomers occurred in the relative proportions 52–55, 41–42 and 4–6%, respectively. These proportions are independent of the origin of the sample. The tentatively identified 9t,12c,15t-18:3 also occurred in some instances. In 2 of the spreads, total geometrical isomers of linolenic acid accounted for 0.9–1% of the total fatty acids (up to 28% of the total 18:3n-3 fraction). The presence of 18:3n-3 geometrical isomers in the spreads is likely due to rapeseed or soybean oils that were deodorized under rather harsh conditions before these were blended with other fats or oils. Partial hydrogenation of these oils may also contribute to accumulation of the same linolenic acid isomers in the spreads.     

方型传力杆在水泥混凝土路面施工中的应用

在水泥混凝土路面工程施工中,用方形传力杆代替圆面传力杆施工,可以很好地解决常用传力杆施工中存在的问题。