Influence of maize kernel hardness on flour hydration and cooking properties

Knowledge of the association between cooking properties and endosperm hardness may help nutritionist and processors to select raw materials for preparing maize based food products, particularly those eaten as cooked dispersions. Seven commercial maize cultivars differing in hardness were selected to evaluate endosperm hardness on the kernels and some characteristics such as composition and hydration and cooking properties on the grits obtained from those maizes. Results show that the differences in endosperm hardness (directly related to grits protein content) can explain the differences in swelling and amylographic consistencies values. Cultivars with the hardest endosperm show the lowest values at high temperature. They also show the lowest amylographic consistencies. On the other hand softer endosperms present the highest swelling power and the highest amylographic consistencies. These differences are attributed to the restriction for starch swelling caused by the protein matrix. Endosperm hardness measurements and swelling power at 95 degrees C, can be useful to select cultivars that are going to be used to prepare maize based foods like atoles, polenta, etc.     

异向旋转双螺杆挤出机的发展前景

本文通过分析螺杆在不同区段的几何特征及其对相应加工阶段的影响对平行和锥形双螺杆挤出机进行了全面的比较。     

Low-field 3-DFT MRI: conceptual, analytical, and experimental aspects

Three-dimensional Fourier transform (3-DFT) magnetic resonance imaging (MRI) offers advantages in terms of signal-to-noise (S/N) per unit of time for the case where a large number of slices is desired. This advantage is enhanced when the relaxation time, T(1 ), is short. Because time limitations in 3-DFT imaging force the use of short time intervals, TR, between excitations of a slice, lesion contrast is often undesirable at mid-and high-field strength even when the S/N is good. At low fields, where T(1) values are short, high S/N and contrast can both be achieved with 3-DFT MR images. The conceptual and analytical aspects of low-field 3-DFT MRI are presented and demonstrated at 640 G.     

When the earth moved...

Northern California directors & dietitians are still talking about where they were, what they were doing & what they learned when the most severe earthquake ever hit their region. The sights & sounds & the lessons revealed by a world turned upside down live on in the following recollections.     

硬质合金晶粒长大的计算机研究

细晶粒的硬质合金粉末广泛应用于诸如整体立铣刀和微钻等工具：对于生产细晶粒的硬质合金来说，有关硬质合金晶粒长大方面的知识尤为重要。在本研究中，使用蒙特卡罗(Monte Cado)计算机模拟技术对硬质合金晶粒持续和断续的生长过程进行了研究。模拟中假定Ostwald成熟过程(溶解／再沉淀)和晶界迁移过程为晶粒长大机理，研究了液相成分、晶界能以及粗晶嵌入的影响。模拟结果，从定性方面来看和实验结果是相符的。这些结果表明，液相分布、WC／WC晶界能以及粗晶的夹杂是抑制硬质合金晶粒断续长大的重要因素。     

适用于高质量锻件的二次炼钢

<正> 一、前言英国钢铁公司的River Don工厂同由Johnson和Firth Brown团体组成的几家公司(其中最大的是Firth Brown公司)合并后成立的塞菲尔德锻造加热控制装置有限公司(Sheffield Forgemasters Limited)于1982年12月开业。该新公司的两个最大部门在贸易活动方面相互补充。其中River Don Works专门制造重型锻件(锻件重量     

不锈钢在高温水中应力腐蚀试验评定方法的比较

一、引言 304不锈钢在核电工业中应用相当广泛,但该材料在高温高压水中的SCC倾向是一严重问题,对此已有不少研究和评述。近年来,对316型不锈钢在高温水中的SCC行为也进行了研究。普遍认为,不锈钢上氧化膜的稳定性及其破裂后的再钝化能力,是影响SCC裂纹萌生和扩展的一个重要因素;304钢在高温水中的SCC属于破膜和局部阳极溶解机理。但有关研究304钢SCC行为与其表面氧化膜的组成和结构之间关系的报道还不多。     

有助于节能的CONFORM连续挤压工艺(上)

由于在金属的生产和加工过程中需要大量能耗,所以,工业界对确定可实现节能的各个领域,无论是直接节能,或是通过更有效地利用材料而间接节能都产生了特殊的兴趣. 概括地说,这些节能领域如下: 1.直接节能方面包括:(1)在合理制定工艺的基础上改进对各个工序的控制(即把热加工生产各工序中的时间-温度条件减到最