Properties of paper coated with kaolin: The influence of the rheological modifier

The first part of this paper analyses the influence of the molecular weight and concentration of carboxymethyl cellulose (CMC) and of kaolin concentration on rheology of the coating colours and on paper properties coated with ultra lightweight coatings (ULWC). In the second part, relationships between the rheological characteristics of the coating colour formulations and coated paper surface quality was also studied.New indexes on paper roughness at micro-scale are presented (RZI and SRI). In general, they show good correlation with sheet gloss. A new gloss index (SGI) is presented, accounting for the contribution of gloss from machine direction (MD) and cross direction (CD). Porosimetry was used to access microstructural characteristics in order to correlate them with light scattering and gloss properties. The former property is closely related to Hg intrusion volume of the coated layer while gloss is related to surface porosity with pore diameters in the range of 7–15 μm as measured by Hg intrusion volume.     

A comprehensive model of colour appearance for related and unrelated colours of varying size viewed under mesopic to photopic conditions

CIE has recommended two previous appearance models, CIECAM97s and CIECAM02. However, these models are unable to predict the appearance of a comprehensive range of colours. The purpose of this study is to describe a new, comprehensive colour appearance model, which can be used to predict the appearance of colours under various viewing conditions that include a range of stimulus sizes, levels of illumination that range from scotopic through to photopic, and related and unrelated stimuli. In addition, the model has a uniform colour space that provides a colour‐difference formula in terms of colour appearance parameters. © 2016 Wiley Periodicals, Inc. Col Res Appl, 42, 293–304, 2017     

UPLC-ESI-MS/MS analysis of Sudan dyes and Para Red in food

An analytical method for the simultaneous determination of Sudan dyes (Sudan Red G, Sudan I, Sudan II, Sudan III, Sudan Red 7B and Sudan IV) and Para Red in food by ultra-performance liquid chromatography-electrospray tandem mass spectrometry (UPLC-ESI-MS/MS) was developed. Samples were extracted with acetonitrile, and water added into the extract. The supernatant was analysed by UPLC-MS/MS after refrigeration and centrifugation. The sample was separated on an Acquity BEH C₁₈ column, and detected by MS/MS with the multiple reaction monitoring mode. Matrix calibration was used for quantitative testing of the method. The linear matrix calibrations of Sudan dyes and Para Red were 2–50 and 10–250 ng g^?1, respectively, and the regression coefficients were >0.9945. The recoveries were 83.4–112.3% with good coefficients of variation of 2.0–10.8%. The limits of detection were between 0.3 and 1.4 ng g^?1 for the six Sudan dyes, and between 3.7 and 6.0 ng g^?1 for Para Red. The limits of quantification were between 0.9 and 4.8 ng g^?1 for the six Sudan dyes, and between 12.2 and 19.8 ng g^?1 for Para Red.     

Colour and label evaluation of commercial pasteurised red juices and related drinks

Despite growing demand by consumers for healthy beverages, artificial colours are still widely used. Levels of anthocyanins and artificial colours were determined by HPLC with UV-Vis detection in red orange juices and other red beverages (nectar, juice-based, health, carbonated and sports drinks). The contribution of pigments to the visible colour of the beverage was calculated. Red orange juice samples contained about 34?mg?l^?1 of anthocyanins, which were responsible for about 92% of the visible colour. Red juice-based drinks, containing from 0% to 30% of red orange, berry, grape or pomegranate juices, had low levels of anthocyanins (about 7?mg?l^?1) and high levels of E129 (about 32?mg?l^?1), which were responsible for about 90.7% of the colour of these beverages. Red health drinks, enriched with vitamins and polyphenols, contained from 3% to 50% of red fruit juices. Also in this case the E129 levels were higher (about 22?mg?l^?1) than anthocyanins (about 9?mg?l^?1), and were responsible for the colour of the beverages (76.1%). High levels of artificial colours were found in red orange carbonated drinks, but in comparable amounts with those found in the other beverage samples, while anthocyanins were only present in trace amounts. Although all of the beverages claimed to contain red fruits on the labels, no correlation was found between the level of anthocyanins and the declared percentage of red fruits. These labels generally conformed with the requirements of the law, but food product labels can often be misleading to consumers about the real characteristics of the product.     

服装流行色的季节差异及关联性研究

为揭示服装流行色的季节差异及其变化规律,以2012-2019年中国服装流行色定案为研究对象,依据中国色彩标准体系(CNCS)对色彩进行量化,采用统计分析与灰色关联分析,探究季节服装流行色的波动规律与色彩特征。结果表明:服装流行色呈现一定的季节差异,不同色彩存在不同的季节模式,即春夏以高明度、高纯度和暖色系为主,秋冬则会增大低/中明度、低/中纯度和冷色系色彩的使用比例;秋冬服装流行色会受到春夏流行色的影响,但不同色彩的关联度存在差异;秋冬服装流行色的波动较大,春夏服装流行色的波动则比较平缓。     

食品中色素检测的研究进展

文章详细介绍了食用色素和违禁染料的定义、分类、特点,以及国内外对于色素类检测技术的研究现状,提出了未来色素类检测技术的重点、难点和发展趋势。     

Full Wave Modelling of Light Propagation and Reflection

The propagation and reflection of electromagnetic waves in a three‐dimensional environment is simulated, and realistic images are produced using the resulting light distributions and reflectance functions. A finite difference time domain method is employed to advance the electric and magnetic fields in a scene. Surfaces containing wavelength scaled structures are created, the interaction of the electromagnetic waves with these nano‐structured materials is calculated, and the sub‐surface interference and diffraction effects are modelled. The result is a reflectance function with wavelength composition and spatial distribution properties that could not have been predicted using classic computer graphic ray tracing approaches. The techniques are employed to reproduce demonstrations of simple interference and diffraction effects, and to create computer‐generated pictures of a Morpho butterfly.     

Usage pattern of synthetic food colours in different states of India and exposure assessment through commodities preferentially consumed by children

Exposure studies in children are emphasized nowadays given children's higher consumption vulnerability. The present study generated national-level data covering 16 major states of India on the usage pattern of colours and it identified food commodities through which a particular colour has the scope to exceed ADI limits. Out of the total analysed samples, 87.8% contained permitted colours, of which only 48% adhered to the prescribed limit of 100?mg?kg^?1. The majority of candyfloss, sugar toys, beverages, mouth fresheners, ice candy and bakery product samples exceeded the prescribed limit. Non-permitted colours were mostly prevalent in candyfloss and sugar toy samples. Though sunset yellow FCF (SSYFCF) and tartrazine were the two most popular colours, many samples used a blend of two or more colours. The blend of SSYFCF and tartrazine exceeded the prescribed limit by a factor of 37 in one sample, and the median and 95th percentile levels of this blend were 4.5- and 25.7-fold, respectively. The exposure assessment showed that the intake of erythrosine exceeded the ADI limits by two to six times at average levels of detected colours, whereas at the 95th percentile level both SSYFCF and erythrosine exceeded the respective ADI limits by three- to 12-fold in all five age groups. Thus, the uniform prescribed limit of synthetic colours at 100?mg?kg^?1 under Indian rules needs to be reviewed and should be governed by consumption profiles of the food commodities to check the unnecessary exposure of excessive colours to those vulnerable in the population that may pose a health risk.     

Testing the relative conspicuity of safety garments for New Zealand forestry workers

The relative conspicuities of six test garments (fluorescent orange, green/red, high-contrast, fluorescent lime-yellow, white, black) were assessed to guide the selection process of a standard upper body safety garment to be used within the New Zealand logging industry. Six male and four female participants, aged between 18 and 26 years, volunteered to perform 10 trials each on a demanding, central (tracking) task, while peripherally searching colour slides for test garments displayed on each of eight positions, against a pine forest background typically found in the New Zealand forestry. During each trial, transparency luminance was first gradually increased from darkness to daylight and then decreased to darkness again within 180 s. A head mounted ASL eye tracking system (4000SU) recorded the eye line of gaze for each participant, enabling a rank order of detection to be obtained for the tested garments in each trial. The fluorescent lime-yellow, fluorescent orange and white test garments were detected earlier than any other test garments across all trials, and the fluorescent lime-yellow test garment was detected first with a higher frequency than the white test garment. It was concluded that while white may be the most visible colour in near darkness conditions, as it provides highest contrast, fluorescent lime-yellow stands out better in twilight and daylight conditions against the pine forest background. The results of this study led to the promotion of fluorescent lime-yellow as the standard safety colour used in upper body garments within the New Zealand forest industry.     

大尺寸AMOLED的技术难题和新进展

自有机薄膜电致发光现象被发现以来,其自发光、高效率、超轻薄、低功耗和可弯曲的特点备受显示界的青睐.近年来OLED蓬勃发展,从MP3到中小尺寸的显示器均已产业化.但在大尺寸显示方面仍存在多方面的问题.从材料、基板和彩色化等几个方面讨论了大尺寸AMOLED的现状、遇到的困难以及新的进展.