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21.
根据所藏月光石的光薄片鉴定研究,阐述了月光石的美学特征和产生原因。介绍了月光石的产出特征和相应的月光石文化,同时介绍了我国关于“和氏壁”属性与月光石关系的研究历史及现状。 相似文献
22.
R. J. Henry 《Journal of the Institute of Brewing》1985,91(6):393-396
A scanning near-infrared reflectance spectrophotometer was calibrated for the prediction of barley aleurone colour and malt moisture. The malt moisture was predicted on malt ground for the determination of malt extract (coarse grind) making the method suitable for moisture correction in malt extract estimation. Calibrations for the prediction of malt extract and endosperm modification from barley and malt were also attempted. A correlation (r= 0.851 n = 135) was found between malt hot water extract and the percentage of the endosperm estimated as being modified by microscopy following staining with Calcofluor. Probably because of this influence of modification on malt extract, the use of near-infrared reflectance to predict malt extract was most successful at predicting the malt extract values obtained following micro-malting in the absence of the additives, gibberellic acid and potassium bromate. 相似文献
23.
Kenneth W. Young Kevin J. Whittle 《Journal of the science of food and agriculture》1985,36(5):383-392
Hunter L, a and b values are used to order fish mince colour according to species or processing parameters. Mince colour difference (ΔE) or statistical examination of L, a and b values are used to establish a 3-dimensional plot to illustrate colour differences between samples. 相似文献
24.
A modified CIECAM02 colour appearance model, named CIECAM02‐m2, is proposed to enable CIECAM02 to predict the simultaneous contrast effect. The structure of the CIECAM02‐m2 is a development from CIECAM02, and contains two different procedures for modifying the reference white; one is for lightness and the other is for hue. The model was tested using a data set accumulated in this study and the LUTCHI data. The CV values for three colour attributes between predictions and experimental data were used to evaluate the accuracy of the model. The low CV values obtained show the performance of the CIECAM02‐m2 model to predict the simultaneous contrast effect satisfactorily. © 2007 Wiley Periodicals, Inc. Col Res Appl, 32, 121 – 129, 2007 相似文献
25.
Aleksej G. Voloboj 《Computer Graphics Forum》1993,12(5):289-296
The paper describes the colour approximation problem and the method of dynamic palette construction is suggested for its solution. The method uses the graphic display palette based on the computed true colour of the individual picture. Some aspects of human colour perception are considered. Two metrics in colour space are introduced to estimate closeness of the suggested colour approximation. The method was applied to visualize 3D scenes generated by ray tracing. 相似文献
26.
介绍铝及铝合金阳极氧化膜颜色的概念和描写,对颜色的儿种测量方法进行了比较,重点分析观察法及其在各国标准中的异同。在此基础上,提出了GB8013中的对颜色进行观察的条件和理论根据。 相似文献
27.
PVC挤塑制品的着色 总被引:1,自引:0,他引:1
通过对PVC挤塑材料性能的分析,探讨了影响PVC挤塑制品着色的主要因素;从原材料及加工过程的特点,寻找控制着色产品色泽的主要因素;认为对材料的配方及配混工艺、挤塑加工工艺进行严格控制,是控制好PVC挤塑制品色泽的主要途径。 相似文献
28.
29.
A glassceramic material, which can be used in stomatology for production of dentinal layer of the dental crown multilayer coating, was received. In order to colour the material the admixtures of Tb and Ce compounds were used, as well as composite admixture representing a mixture of Ce, Nd and La oxides. It was demonstrated that the admixture of Tb oxide tones the material only when it is used together with Ce oxide. It was found that the more admixtures of rare earth elements oxides are contained in the sample composition, the higher the colour strength of the sintered material is. The wave length for the test samples is in the range of 600~650 nm, which corresponds to the yellow-orange and orange-red spectral range. 相似文献
30.
通过对GB 11186-1989《涂膜颜色的测量方法》标准中关于CIE 1964补充标准色度系统、CIE 1976(L*a*b*)色空间的色坐标及色差公式和光与颜色的相关理论的分析,解析了GB/T 8814-2004《门、窗用未增塑聚氯乙烯(PVC-U)型材》中有关型材颜色测量要求,并给出了灰卡级数与总色差的换算关系。 相似文献