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21.
Birthe Mller Jose Luis Molina‐Cano Lars Munck 《Journal of the Institute of Brewing》2002,108(3):294-302
In earlier studies concerning vigour, where subsamples are heat‐treated before germination there was found heat‐sensitive as well as heat‐resistant barley samples. The vigour model developed by Ellis and Roberts and further developed at Carlsberg, could only describe the heat‐sensitive barleys. Seventeen samples of the “Alexis” variety grown widely in Europe were collected from the EBC trials in 1994 in order to see if heat resistance in barley was influenced by different growing conditions. We found both heat‐sensitive samples following the vigour model as well as pronounced heat‐resistant samples, but these were not divided according to growing conditions. The germination curves dependent on heat treatment and germination time were evaluated by Principal Component Analysis (PCA). Heat‐resistant barley samples could be differentiated from heat‐sensitive samples already after ½ h of heat treatment at 68°C (12% moisture) and after 3 days of germination. The barley samples were analysed with regard to malting quality. The PCA evaluation of the data divided the samples according to growing location, mainly due to differences in protein and β‐glucan. However, the malting analyses could not describe the differences in heat resistance and sensitivity of the barleys. The biochemical background of the heat resistance found is discussed on the basis of literature. Our findings should give an experimental basis for exploiting a biochemical principle for heat resistance, which is formed during grain filling and consumed during storage and germination. 相似文献
22.
抚顺石油一厂通过大量试验和溶剂脱蜡装置的连续生产证明:加工减二线,套管易上压,滤机上蜡饼泡松易堆蜡,应选用合适的改进剂以控制蜡晶生成树枝状;减四、五线重馏分蜡晶细密,套管不易上压,滤机易失效,应选用和适当加入合适的改进剂以增大聚集状晶体粒度;减三线蜡晶粒度大,为套管上压周期较长,滤机上蜡饼通透性好,滤速快,可根据需要决定是否使用改进剂。提出了针对不同润滑油馏分中不同蜡晶型选用合适的蜡晶改进剂可以相应解决不同馏分的生产难点,提高处理能力,改善产品质量。 相似文献
23.
EPON技术具有大带宽、高性价比、结构简单和一定服务质量保证等特点,被业界普遍看好,成为 下一代接入网的最佳候选技术.本文主要介绍了EPON的工作原理、分层结构、接入控制和组帧方式,最后给出 了实现EPON的关键技术和难点以及EPON的发展近况. 相似文献
24.
部件试验模态综合的简便方法 总被引:4,自引:1,他引:3
本文将一种基于完备模态基的模态综合技术应用于子结构的试验模态综合,获得成功。这种半试验半理论的模态综合方法是一种较为简便的、要求试验工作量较小的试验模态综合法,因为它只要求测量子结构的振动模态和频率即可。数值仿真结果表明,这种简便的试验模态综合法是行之有效的。 相似文献
25.
本文介绍亚州第一台模拟分量电视车视频系统的设计思想,比较详细地阐述了该车的各种功能,总结了不同于复合电视车的新特点。 相似文献
26.
M. Safar D. Bertrand P. Robert M. F. Devaux C. Genot 《Journal of the American Oil Chemists' Society》1994,71(4):371-377
The combination of attenuated total reflectance (ATR) and mid-infrared spectroscopy (MIRS) with statistical multidimensional
techniques made it possible to extract relevant information from MIR spectra of lipid-rich food products. Wavenumber assignments
for typical functional groups in fatty acids were made for standard fatty acids: Absorption bands around 1745 cm−1, 2853 cm−1, 2954 cm−1, 3005 cm−1, 966 cm−1, 3450 cm−1 and 1640 cm−1 are due to absorption of the carbonyl group, C−H stretch, =CH double bonds of lipids and O−H of lipids, respectively. In
lipid-rich food products, some bands are modified. Water strongly absorbs in the region of 3600–3000 cm−1 and at 1650 cm−1 in butters and margarines, allowing one to rapidly differentiate the foods as function of their water content. Principal
component analysis was used to emphasize the differences between spectra and to rapidly classify 27 commercial samples of
oils, butters and margarines. As the MIR spectra contain information about carbonyl groups and double bonds, the foods were
classified with ATR-MIR, in agreement with their degree of esterification and their degree of unsaturation as determined from
gas-liquid chromatography analysis. However, it was difficult to differentiate the studied food products in terms of their
average chainlength. 相似文献
27.
Multiple forms of a symbol-digit substitution task were used to provide a componential analysis of age differences in coding task performance. The results demonstrated age differences in feature encoding, memory, and visual search. A 2nd experiment was conducted with young adults to investigate a sensory deficit as a locus of age differences. The spatial contrast sensitivity deficit of older adults was simulated on forms by applying a digital filter. Persons in the age-simulated contrast condition performed worse than those in the normal contrast condition. The stimulus degradation effect was linked to visual search speed. The study illustrates the utility of componential analysis and offers direct support for the hypothesis that sensory deficits affect performance on tasks used to assess intelligence (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
28.
William E Acree Jr Michael H Abraham 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2006,81(8):1441-1446
The contentions made in an earlier paper [J Chem Technol Biotechnol 80 : 133–137 (2005)] that the coefficients of the Abraham solvation equation do not provide meaningful information on the molecular properties of ionic liquid solvents is refuted. The objections noted in the earlier paper disappear when the solvation equation model is correctly applied to the experimental data. It is further shown that the coefficients of the Abraham solvation equations can be used to characterize ionic liquids and can be used to select solvents for the solubility of gaseous solutes. Copyright © 2006 Society of Chemical Industry 相似文献
29.
塔巴庙区块气藏属于低压、低渗气藏,储集层物性差异大、含气级别高,但含气非均质性强,录井解释评价困难。针对这一问题,开展了综合判断储集层物性和含气性方面的研究,分别探讨了钻时与全烃、钻井液性能与全烃、钻井液粘度与全烃、气测显示与测井参数和烃组分与气显示之间的关系,分析了其相关性及其在塔巴庙区块气层解释评价中的意义及作用。通过相关性研究,不但摸索出定性解释评价气层的方法,同时为今后深入研究录井相关参数关系,探索其内在规律,为实现准确解释评价储集层奠定了基础。 相似文献
30.
Stress analysis of pin-loaded woven-glass fiber reinforced epoxy laminate conveying chain components
The aim of this study is to examine the effects of various loading conditions on the stress of a pin-loaded woven-glass fiber reinforced epoxy laminate conveying chain component. A numerical and experimental study was carried out to determine the stress distribution of composite conveying chain components used to convey loads. For the experimental study, an apparatus was developed to simulate chain components in real motion. Two different working conditions of the chain component were investigated. The first condition represents the movement of the chain components without loading. In the second condition, the chain component touches and moves the load. The commercial finite element package ANSYS was used to perform the numerical analysis using a three dimensional eight-noded layered structural solid elements. Chain tensile forces were loaded through pins and chosen as 250, 500, 750, 1000 and 1250 N for the two conditions of chain components. Experimental and numerical studies were compared and discussed for two conditions and five different tensile forces. A good agreement between experimental results and numerical predictions is obtained. 相似文献