Effect of ripeness and postharvest storage on the evolution of colour and anthocyanins in cherries (Prunus avium L.)

The relationship between colour parameters and anthocyanins of four sweet cherry cultivars, Burlat, Saco, Summit and Van was studied. The colour (L^∗, a^∗, b^∗, chroma and hue angle parameters) and anthocyanins were analysed during two different years at two different ripening stages (partially ripe, and ripe, respectively). The cherries were analysed at harvest and after storage at 1.5 ± 0.5 °C and 15 ± 5 °C for 30 and 6 days, respectively. The colour was measured by tristimulus colourimetry (CIELAB system) directly on the fruits, while anthocyanins were quantified by HPLC-DAD analysis on methanolic extracts of freeze-dried samples of the fresh cherries and on the differently stored cherries. L^∗, chroma, and hue angle values were always lower for the ripe than for the partially ripe cherries. All of the cultivars were found to contain cyanidin-3-rutinoside and cyanidin-3-glucoside as the major anthocyanins. The total anthocyanin content in fruits of the different cultivars varied in the order Burlat > Saco > Van > Summit. The concentration of anthocyanins increased at both temperatures of storage in both ripe and partially ripe cherries, but the extent of increase varied among cultivars. Cherries stored at 15 ± 5 °C showed higher reduction of L^∗, chroma and hue angle than fruits stored at 1.5 ± 0.5 °C. L^∗, a^∗, b^∗, chroma and hue angle correlated negatively (P < 0.001) with the total anthocyanins levels, but not with the total phenols. These results show that chromatic functions of chroma and hue correlate closely with the evolution of colour and anthocyanins levels during storage of sweet cherries and indicate that colour measurements can be used to monitor pigment evolution and anthocyanin contents of cherries (and vice versa).     

EFFECT OF EDTA ON COLOR DURING OSMOTIC DEHYDRATION OF BANANA SLICES

ABSTRACT

Five conditions of the osmo-dehydration process of banana slices, which in our previous study underwent the most adequate color parameters changes were used with the presence of EDTA added to the syrup solutions at five concentrations of 0.01, 0.05, 0.1, 0.5 and 1% w/w. EDTA presence did not change the tendency of polyphenol activity decrease during osmotic drying as well as has not effect on chroma, hue and total color difference changes. EDTA presence had an effect on L value decrease in the inner and outer part of the slice, and did not depend to osmotic dehydration conditions. It is highly recommended to use EDTA during osmotic dehydration of some fruits that would undergo undesirable darkening.     

适合硬件实现的解决色度上采样错误的算法实现

为了适应视频后处理芯片低成本的需求,提出一种每场仅需用两行缓存、适合硬件实现的解决色度上采样错误的算法。首先,检测出现色度上采样错误的地方;然后,对上采样错误的地方进行处理。具体表现为,检测出有上采样错误的地方,用帧处理方法来进行修复;否则用传统的场处理方法来处理。实验结果表明该算法在较少的资源下,仍然可以有效检测到出现CUE现象的像素点,较好地解决了该错误,并且便于硬件实现,可应用于低成本的数字视频后处理芯片中。     

64 cm FS彩色显像管白场品位的提高

通过对64cmFS彩管白场的测试及分析，确定提高白场色度及亮度比是提高整管白场品位的关键．经过对涂屏工艺条件的优化，对曝光台主透镜曲面及荫罩槽宽的优化设计，使该管型白场品位低下的顽疾得到明显改善。     

催化铁内电解法降低城市生活污水生化出水色度

研究了催化铁内电解法对城市生活污水生化出水色度去除的影响。喷淋式装置的水力停留时间2h,当铁铜比例为12∶1,出水色度值最低,基本都在10以下。当铁铜质量比为4∶1时,TN去除率可以达到10%以上;出水NO_3~-减少量最大,去除率大约为24.5%;NH_4~+的增加量可以达到3mg/L左右。     

UV/O3/H2O2化学氧化活性艳蓝KN-R

以商品染料活性艳蓝KN-R为研究对象，利用VC／O3/H2O2技术进行氧化处理。考察了染料溶液在此过程中的pH、电导率、COD、TOC和吸光度的变化。经过70min的氧化过程，结果表明，溶液的pH降低、电导率不断升高、色度去除率达98．9％，溶液的COD和TOC去除率分别为47％和5％。VC／O3/H2O2技术与UV/H2O2氧化法相比，UV／O3/H2O2能显著去除染料溶液的色度。     

色度在评价增强图像时对传统算法的修正效果

增强图像是指与原始图像相比在清晰度、亮度、色彩、对比度等方面有一定增强的图像.图像增强已被广泛应用,例如很多图像处理软件PS,ACDSee等都能够对图像进行增强.与此同时,也出现了很多图像增强算法.所以,对增强图像的质量评价具有重要意义.传统的图像质量评价算法不能够对增强图像进行精确评价.增强图像与原始图像相比,在色度上存在一定差异.在此基础上,研究了色度在评价增强图像质量时对传统的图像质量评价算法的修正效果.在增强图像数据库中进行的实验证明在评价增强图像质量时,色度能够对传统的图像质量评价算法进行较好的修正.     

基于参数查找表的肤色检测算法

针对现有模型对肤色空间刻画的不足,提出了一种基于参数查找表的肤色检测算法。该方法将肤色和非肤色看作两类模式,通过在YCbCr颜色空间统计,计算样本在不同色度下沿亮度的概率分布,分类采用贝叶斯判别规则,查找表用于存储模型参数,实现了快速查找和计算。实验中,从像素样本分类和彩色图片分割两个方面对算法的检测性能进行对比,说明其有较高的检测率和较强的鲁棒性。     

电化学氧化处理腈纶废水及水质指标相关性

采用电化学氧化技术处理腈纶厂生化池废水,运用国标测试方法对COD、氨氮、色度和氯离子等4项指标进行了分析。结果表明:色度得到有效降低,氨氮、COD得到有效去除。其中,氨氮的去除率达100%,色度降低幅度99%,COD去除率可达89%,氯离子的质量浓度亦可以降至国家一级排放标准,说明电化学氧化技术具有良好的应用前景。通过分析可知:色度在5min内能得到有效降低,氨氮在30min内能得到有效去除,且氨氮的去除速率是电解电压的一次函数;氯离子在溶液中的反应呈现一级反应的特征;COD的去除速率常数与氯离子的去除速率常数具有良好的相关性。这一结果对电化学氧化反应器的设计和工业化运行具有指导性意义。