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41.
Discusses retouching of the Kallikak family photographs in H. H. Goddard's (1912) study of mental retardation and heredity, with reference to analyses by R. E. Fancher (see record 1987-31600-001) and S. J. Gould (1981), and concurs with Fancher that the retouching was probably not done for deceitful purposes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
42.
43.
为提高舌控智能辅助系统舌部运动信息的采集精度,利用STM32H743和LabVIEW设计了一种对舌机接口辅助系统进行信号采集、传输的通信装置.该装置通过舌部触碰嵌入式电极传感器发出信号并传输给单片机(进行舌控信号采集),然后通过串口传给上位机以此最终实现数据的采集与保存.实验结果表明,该装置可有效完成舌控智能辅助系统对控制信号的采集与传输,并具有实时显示、自动保存和查询历史数据等功能; 因此,该装置在舌控智能辅助系统的信号采集中具有良好的应用前景. 相似文献
44.
We investigate the thermodynamics, kinetics, and capacity of the hydrogen storage reaction: Li2Mg(NH)2 + 2H2 Mg(NH2)2 + 2LiH. Starting with LiNH2 and MgH2, two distinct procedures have been previously proposed for activating samples to induce the reversible storage reaction. We clarify here the impact of these two activation procedures on the resulting capacity for the Li–Mg–N–H reaction. Additionally, we measure the temperature-dependent kinetic absorption data for this hydrogen storage system. Finally, our experiments confirm the previously reported formation enthalpy (ΔH), hydrogen capacity, and pressure–composition–isotherm (PCI) data, and suggest that this system represents a kinetically (but not thermodynamically) limited system for vehicular on-board storage applications. 相似文献
45.
46.
XK5159H钢连铸连轧棒材用于制造矿山磨光球,对于钢的纯净度、低倍组织、探伤结果及DI值等均有严格的要求,很难控制。我们通过制定内控化学成分及合理的工艺路线,使生产试制一次成功。 相似文献
47.
In this paper, the author dipped surface vapor oxidized H13 steel specimens into 700℃ molten aluminum liquid for a certain period of time. Analyze the intermetallic phases formed on the H13 samples surface with optical microscope and X-ray diffraction method. The observation of immersion test sample's cross-section shows that Fe3O4 film will protect die substrate from molten aluminum erosion. The identification of the intermetallic phases reveals that they consist of 2parts, which is named as the composite layer and the compact layer. Further investigations are made in order to know the phase constituents of the 2 layers, they are Al8Fe2Si (outer composite layer), (AlCuMg) and Al5Fe2 (compact layer),respectively. The experimental results show that on the same specimen, a convex surface with bigger radius of curvature is more likely to be molten and the melting loss speed is also faster than a flat and smooth surface. The thickness of compact layer on a smooth surface is much bigger than that of the convex surface. Therefore, the author supposes the compact layer is favorable in stabilizing the die surface material from further melting loss, as their formation on the die surface, the melting loss speed will decrease. 相似文献
48.
Symmetrical and non-symmetrical triacylglycerols (TAG) containing oleic (O; 9c-18:1) and elaidic (E; 9t-18:1) acids were required
as part of a study relating the physical characteristics and functionality of trans-containing TAG with the mouth feel, taste characteristics and related characteristics desired by consumers in frying oils
and pastries. To replace the trans isomers in frying oils—a significant part of frying oils prepared by partial hydrogenation of vegetable oils—without loss
of the sensory properties desired by consumers, required the initiation of a study relating the structure of trans-containing TAG with such characteristics as melting range, drop points, and other crystalline properties. Elaidic acid was
esterified to trielaidin (EEE), and the EEE partially converted (glycerol/p-toluenesulfonic acid) to a mixture containing ca. 40% DAG (the 1,3- and 1,2-isomers). The DAG fraction was separated by silica
gel chromatography, the 1,3-dielaidylglycerol (1,3EE-DAG) isomer isolated (structural purity >99%) by crystallization from
acetone and esterified with oleic acid (O) to yield EOE. The 1(3)O-MAG was purchased commercially and esterified with E acid
to prepare OEE. Both syntheses yielded multi-gram quantities of EOE and EEO, in 80–85% yields, and with structural purities
>99%. Thus, by careful selection of the thermodynamically more-stable MAG or DAG precursors, the symmetrical EOE and non-symmetrical
EEO isomers could be readily synthesized, and their drop point and melting point values determined.
The 1- and 3- positions on the glycerol backbone of the MAG, DAG and TAG molecules are assumed to be equivalent. 相似文献
49.
探讨了该厂化肥生产中碳铵发青的原因,通过硫化氢含量的测定,分析了系统内外影响因素,提出了解决措施,达到了不停车稳定产品质量的目的。 相似文献
50.