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1.
水性无树脂色浆体系的研究与制备   总被引:1,自引:0,他引:1  
相对于含树脂的色浆体系,无树脂色浆体系具有通用性强等特点。文章讨论了水性无树脂色浆制备过程中的影响因素,如颜料、分散剂、消泡剂以及流变剂等,其中在制备有机色浆过程中,超分散剂具有分散性好、稳定性强等特点;确定了无机和有机通用色浆的配方。采用高速分散、研磨等工艺,制备出贮存稳定、相容性良好以及环保的水性色浆,通过SEM观察了色浆的分散状态,测试了其基本性能,如细度、耐化学性等。讨论了色浆的评价方法和色浆在涂料中的应用。  相似文献   

2.
Huihui Yao  Li Li 《Lipids》2019,54(5):301-309
Chronic diseases are gradually becoming public health challenges around the world. This study was designed to explore the relationship between early life exposure to famine in China and the risk of dyslipidemia during adulthood. A total of 604 subjects born from 1955 to 1965 received a health checkup and completed a questionnaire survey at the health management center of the tertiary hospital in Hefei, China, in 2013. A logistic regression model was used to assess dyslipidemia in famine-exposed and nonexposed individuals. Overall, exposure to famine during the fetal (OR 1.37; 95% CI: 0.90–2.10; and p = 0.14) and childhood (OR 0.97; 95% CI: 0.67–1.41; and p = 0.89) periods did not significantly increase the risk of dyslipidemia in adulthood compared with no exposure group. For females, exposure to famine during the fetal period (OR 2.00; 95% CI: 1.03–3.86; and p = 0.04) significantly increased the risk of dyslipidemia in adulthood compared to no exposure; however, this difference was not found in males. Exposure to famine in early life leads to altered lipid distribution in adulthood, and the risk of dyslipidemia significantly increased in adult women who were exposed to famine during the fetal period. Our study further validated the relationship between famine exposure during pregnancy and increased risk of dyslipidemia in female adult offspring. This study provides a scientific basis for the prevention and control of abnormal blood lipid levels in adults.  相似文献   

3.
Whether we are purchasing fresh vegetables from a market stall, ready meals from the supermarket, eating at home or in a five‐star restaurant, we use colour to tell us what to expect in terms of taste, nutrition and safety. This review considers the techniques that have, over the years, been employed to modify the colour of our food, and the interactions of these techniques with issues of safety and nutrition. The demand for brightly coloured food resulted in the incorporation of some questionable inorganic and organic chemistry being used in food products. A limited number of synthetic dyes are still used in food today, but health concerns and the consumer‐driven demand for natural colorants has brought about a change in the way food is coloured. The proliferation of products with labels that state they contain “No artificial colours” on supermarket shelves suggests that the future of azo dyes and their various derivatives is strictly limited. Nature produces an abundance of colours and many of these are extracted and used as natural food colorants; however, they are subject to application limitations and stability problems. Significant research by academia and industry into methods to stabilise and expand the application possibilities for the various approved natural food colorants is ongoing, but most developments that food colour manufacturers proclaim are enhanced vehicles for delivering established natural pigments into food products.  相似文献   

4.
This study describes the dyeing efficiency of cochineal (Dactylopius coccus Costa) and Monascus purpureus colorants on cotton fabric. The effects of mordant, dyeing time and temperature on the shades and fastness properties of both colorants were studied. The colour coordinate values indicate that the cochineal colorant exhibited higher colour strength than M. purpureus for premordanted cotton fabric (4% owf). Optimum dyeing with M. purpureus was observed at a temperature of 80 °C for 80 min at a 30:1 liquor ratio. However, for cochineal, the optimum dyeing conditions were 60 °C for 60 min at a 40:1 liquor ratio. Furthermore, both colorants demonstrated moderate to good fastness properties. The results of the study indicate that cochineal has better dyeing properties than M. purpureus colorants.  相似文献   

5.
Product appearance is an important factor for consumers when determining the quality of a product, and colour is one of the most important factors which contribute to product appearance. Currently, the safety and consumer acceptance of some colorants used in food products, such as titanium dioxide and some synthetic colorants, are under discussion. Therefore, new ways to use natural colorants as alternatives to these suspect colorants for future applications are being investigated. A promising method for increasing the applicability of the often sensitive natural colorants is the encapsulation of these colorants in colloidal particles by natural polymers such as carbohydrates, lipids and proteins. In recent years, micro‐ and nano‐encapsulation have increasingly been used for various purposes concerning several food properties such as colour, flavour and micronutrient content. This technique results in improved stability for the often sensitive natural colorants and presents the possibility of entrapping water‐insoluble colorants for improved use in an aqueous system. This paper reviews the main methods that are used for encapsulation by natural polymers, discusses the different types thereof that are used for encapsulation of colorants, and provides a short overview of natural colorants successfully encapsulated in these natural polymers.  相似文献   

6.
Size distributions for As, Cd, Bi, Br, Fe, Mn, S, Sb, Tl, K, V, Rb, elemental carbon (EC), organic carbon (OC), sulfate (SO 2? 4 ), chloride (Cl?), and nitrate (NO? 3 ) were measured at Bakersfield and Modesto CA between 12/15/2000–01/07/2001. S and V size distributions were highly correlated with little diurnal variation suggesting that, during stagnant winter conditions, inhalation exposure and epidemiological studies can choose exposure/analysis times of several days during which population exposure will be relatively uniform. In contrast, the size distribution and temporal patterns of Fe are highly variable requiring more frequent measurements and shorter health analysis periods to adequately characterize exposure concentrations. K and Rb (tracers for wood smoke) exhibited nearly identical diurnal size distribution shifts (R 2  > 0.99) with smaller particles emitted at night and larger aged particles evident during the day. This pattern suggests that the health effects of fresh wood smoke could be studied through nighttime inhalation exposure experiments and aged wood smoke could be evaluated through daytime experiments. All of the components’ size distributions were consistent with production by combustion sources and/or secondary chemistry. Future inhalation exposure studies should use a combustion source to generate these particles. Lung deposition calculations predict that 32 ± 11% of PM deposition occurs in the pulmonary region, 61 ± 23% occurs in the respiratory region, and 6 ± 2% occurs in the tracheo-bronchial region for all components. Deposition patterns were highly correlated with PM 1.8 concentrations suggesting that exposure estimates can be developed with bulk filter samples during the current episode.  相似文献   

7.
本文对在水性涂料中的各类着色剂进行了归类;综述了各类着色剂在水性涂料中的应用,包括染料、无机颜料、有机颜料、效应颜料、特种颜料和颜料预制剂;详细地分析对比了常用有机和无机颜料的性能和应用的领域。另外,文章以劳尔色1021油菜黄为例,列举了不同涂料体系中对应的配色方案。  相似文献   

8.
Textiles coloration using extracts from the roots of various madder species (Rubia spp.) has been performed for centuries. To date, 68 anthraquinone colorants have been detected in Rubia spp. used to dye textiles. Many of these dyes are sensitive to hydrolysis and degradation from enzymes, extraction chemicals and processing temperatures, and are often overlooked as colorants in historical textiles. Conclusions in literature of the past 30 years concerning colorants present in planta and, particularly, in madder‐dyed artefacts are being challenged as new analysis methods are developed. The recent advent of ‘soft’ extraction techniques has demonstrated that anthraquinone glycosides and other sensitive molecules, such as carboxylated compounds, need to be preserved; this valuable chemical information embedded in the dye structure may be lost if extraction and analysis is too harsh. Some compounds thought to be present in madder and madder‐dyed artefacts are in fact degradation products resultant from the extraction process, and degradation pathways have been developed to better understand the reactivity and stability of these compounds. Detailed analysis of dyes in textile artefacts can reveal important cultural and heritage information concerning historical textiles relative to the specific dye species, the area of the world where this may have grown, how and where it was dyed, and, perhaps, where it was traded. Understanding the precise molecular structure of these dyes and their chemical reactivity is important to provide knowledge of their interactions with physical substrates, such as textile fibres, which could be used to develop superior techniques for analysis of artefacts.  相似文献   

9.
The creation of the first synthetic dyes not only stimulated the hunt for new colorants but also drove the search for rules correlating the constitution of organic compounds with their colour. Dye chemistry additionally facilitated the development of molecular electronic spectroscopy as well as theories of molecular electronic structure and electronic transitions. Powerful quantum chemical computational tools are now available for the prediction of the electronic structure and spectroscopic characteristics of organic compounds. Such methods are thus useful in designing new functional colorants and aiding interpretation of their properties. However, without a deep appreciation of the principles and assumptions behind the calculations, one runs the risk of misunderstanding what can be achieved as well as becoming confused about how the outputted electronic and vibronic transition data correspond to observed absorption spectra. This review therefore aims to cover fundamentals of electronic spectroscopy that are often overlooked and enable the dye chemist using modern computational methods to comprehend the subtle differences in the types of transition energy value that such software can generate. In addition, the limitations of these methods in predicting absorption maxima and intensities of real‐world colorants will be discussed in the context of physical influences on absorption band position and shape, for example from the perspective of different forms of the Franck–Condon principle. In essence, the goal of this review is to clarify, in terms that practical dye chemists will understand, what computational methods can predict and how valid these predictions are compared with reality.  相似文献   

10.
建立了用高效液相色谱(HPLC)/二极管阵列检测器(DAD)同时检测粉状化妆品中多种有机着色剂的检测方法。样品采用甲醇+水(1:1)提取溶剂超声提取15min后,以乙腈-磷酸二氢钾缓冲溶液(pH=6)为流动相梯度洗脱,在240nm的波长下用DAD对9种目标物同时进行检测。用保留时间结合目标化合物的紫外吸收光谱定性,外标法定量。方法的平均回收率(n=9)在90.31%-99.10%的范围内,精密度RSD在1.95%-4.61%之间。方法简单、快速,能有效提取和分离测定粉状化妆品中多种有机着色剂。将该方法用于实际样品的检测,结果令人满意。  相似文献   

11.
The use of vivid packaging colors is a strategy to attract consumers' attention and interest. In this context, the awareness of harmful effects caused by the use of synthetic colorants has led to an increasing interest in naturally derived alternatives. The use of carotenoids as colorants for polymeric materials represents an environmentally friendly way of obtaining colored packaging. The incorporation of carotenoids extracts rich in bixin, lycopene, and β‐carotene into poly(lactic acid) films was evaluated, where the presence of carotenoids (100 μg/g) reduced oxygen permeability and presented a lubricant effect, increasing films elasticity up to 50%. No effect on films crystallinity was observed. Carotenoids reduced films transparency and bixin was the most stable carotenoid at dark and light conditions. The color stability of films, evaluated through kinetic parameters of color degradation, presented Chroma half‐life times (40 °C/light) of 111, 51, and 5 days for bixin, lycopene, and β‐carotene, respectively. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46585.  相似文献   

12.
Secondary metabolites in fungi offer an interesting source of bio‐based compounds that could be used as colorants in many applications. From a historical point of view, fungal natural dyes have been used more rarely than plant‐based dyes. This paper investigates the potential of fungal colorants, using Cortinarius species as examples. In our research, fruiting bodies of the fungi Cortinarius sanguineus and Cortinarius semisanguineus were used as sources of anthraquinone dyestuffs. From 10 kg of fresh fruiting bodies, 60 g of anthraquinone powder was obtained, 6% of the dry weight content. The most abundant compounds were emodin, dermocybin and their glucosides, which formed over 90% of the total dyestuff amount. Pure emodin and dermocybin, as well as the crude water extract, were used for the dyeing and printing of natural and synthetic fibres. Conventional mordant techniques and high‐temperature (HT) disperse dye techniques were applied, and light and washing fastness were tested according to International Organization for Standardization standards. Our experiments show that the yields of dye powders extracted from fungi are reasonable compared with the yields of, for example, madder (Rubia tinctorum). Natural anthraquinones produce strong and bright colours on several types of fibres. In particular, for HT disperse dyed polyester, the light and washing fastness properties were excellent. Anthraquinones are common in nature and there are many fungal species which produce them, so there are a variety of possibilities for growing fungi. The use of large‐scale cultures is an interesting perspective for future biocolorant production.  相似文献   

13.
外墙乳胶漆耐候性研究   总被引:3,自引:0,他引:3  
采用天然曝晒和人工老化方法研究了各种纯丙乳液和硅丙乳液的耐候性,由该类乳液制备的不同PVC白色乳胶漆的耐候性,以及白色乳胶漆与各色色浆配制的浅色乳胶漆的耐候性。结果表明:硅丙乳液和核壳型纯丙乳液具有较好的耐候性,高PVC乳胶漆容易变色,炭黑和氧化铁系色浆适合于配制浅色外墙乳胶漆,有机颜料色浆应用在外墙时应谨慎。  相似文献   

14.
Summary Vegetable oil suspensions of ethyl bixin andbeta-carotene, to which vitamin A may be added, have excellent stability and are readily adaptable for use in coloring margarine and other fatty food products. Based on normal finished product turnover these colorants maintain adequate stability. In frying fats and popcorn oils only FD&C Yellows 3 and 4 are completely stable.  相似文献   

15.
我国农药安全风险管理概况   总被引:1,自引:0,他引:1  
李富根  王以燕  宋稳成  高希武 《农药》2012,51(6):393-398
为保障公众健康和环境生态安全,我国采取禁限用农药、严格市场准入、加强残留监控等措施,加强农药安全风险管理。概述了我国农药安全风险管理现状,对近年来农药管理部门出台的政策措施进行了系统归纳总结。同时,尝试在我国创制新农药中应用安全风险暴露评估模型,探索建立农药健康风险评估方法,并提出了相关政策建议。  相似文献   

16.
Blue colors were sparsely used in the first colored Japanese ukiyo-e prints but became predominant during the 19th century, mainly due to the integration of the synthetic Prussian blue in the palette of the printers around 1830. For a long time, researchers have assumed that the traditional Japanese organic blue colorants such as indigo were substituted by cheaper Prussian blue. Some analytical studies conducted on such artworks showed evidence of the common use of indigo and Prussian blue in Japanese paintings, alone or mixed together. Recent measurements carried out on bluish areas of an ukiyo-e designed by Utamaro showed the simultaneous use of the two pigments. However, if visible reflectance spectroscopy suggested the single use of Indigo, Fourier transform infrared spectroscopy (FTIR) also indicated the presence of Prussian blue. These results question about the possible identification of all the pigments of a colored mixture by using a single analytical technique. Without using FTIR spectroscopy, the Prussian blue would not have been detected, whereas on infrared spectra the expected specific bands ascribed to indigo are not identified. The objective of this work is to investigate mixtures of pigments, using noninvasive spectroscopic techniques in order to assess their limits of detection. Fluorimetry, hyperspectral imaging, and infrared spectroscopies have been performed on three color charts made of indigo, Prussian blue, and mixtures of them at different proportions of matter. The results emphasize the systematic identification of Prussian blue thanks to infrared spectroscopy, whereas the identification of indigo, mixed with Prussian blue, appears to be more challenging.  相似文献   

17.
In Europe, considerable amounts of bark are available from wood‐processing industries such as forestry and timber production. Polyphenolic components can be collected by hot water extraction. The extracted compounds can then be applied as colorants in textile dyeing operations. In this study, a comparative assessment of four different tree species with regard to their colouristic potential for wool dyeing was performed. Aqueous extracts from alder, ash tree, spruce and oak bark were prepared and analysed for their total phenolic content and ultraviolet (UV) absorption at 360–370 nm. The extracts were used for meta‐mordant dyeing by adding iron sulphate mordant (FeSO4 × 7H2O). For comparison, iron salt‐based dye lakes were prepared and used in dyeing experiments. For each tree species, a specific correlation between the total phenolic content of the dyebath and the colour depth in terms of K/S and CIELab coordinates was observed, both for the aqueous extracts and the dye lakes. Based on this relationship, standardisation and quality control of raw materials and dye lakes can be installed as important stages in the industrialisation of natural colorants from bark. The preparation of concentrated dye lakes permits formation of a concentrated colorant as dye product, which then can be standardised and delivered to textile dyehouses, similar to synthetic dyes. The preparation of dye lakes offers a relevant route towards achieving the commercialisation of bark extracts as natural colorants.  相似文献   

18.
A series of colorants based on renewable resources and food‐grade colorants have been evaluated for use in polypropylene (PP) and polyvinylchloride (PVC). It has been found that most of these colorants can be processed in PP at 200°C or even 260°C while maintaining good color intensity and color brightness. The colorants evaluated cover a large part of the color spectrum. In PP, the light stability of alizarin (red), carmine (red), indigo (blue), purpurin (red), quinizarin (red), and the aluminium lakes of quinoline yellow (yellow) and indigo carmine (blue) is close to the requirements for indoor applications. The blue colorants indigo and the aluminium lake of indigo carmine are, in principle, sufficiently light stable in PP for indoor applications. A few colorants showed bleeding from PP. Bonding of migrating colorants to the reactive carrier maleic anhydride grafted polypropylene, however, reduced bleeding of the colorant to a large extent. Also after processing in PVC at 200°C, good color intensity and saturation is maintained. Quinizarin, a structural analog of alizarin and purpurin, shows a light stability performance that is close to commercial lead chromate/molybdate orange based colorants. The best performing natural colorants are sufficiently heat and light stable for applications where moderate properties concerning heat resistance and (UV) light stability are required, such as underground PVC water drainage pipes and indoor PP applications. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2961‐2969, 2004  相似文献   

19.
To examine the strengths and limitations of the time-dependent density functional theory in calculating the absorption wavelengths of dye, 130, non-radical, radical and biradical coloured organic compounds, including perylenimide, porphyrin, azobenzene, quinone, croconaine, squaraine and push–pull-type colorants, were randomly selected. The first intense electronic transitions were satisfactorily calculated using time-dependent density functional theory. Whilst polymethine dyes behaved exceptionally, the calculated transition energies for cyanines, oxonols and various related dyes were systematically too large. Broken-symmetry unrestricted density functional calculations revealed the biradical character of several quinoid compounds derived from p-quinodimethane as well as that of some non-Kekulé-type structures.  相似文献   

20.
The colour of inorganic colorants is based on metal ions such as cadmium, lead, chromium or cobalt, the majority of which are unfortunately potentially toxic. Thus, there is in a need to introduce alternative metal or metal oxides, which would be environmentally friendly and economically viable as a replacement for potentially toxic inorganic colorants. Rare earth-based colorants offer an additional opportunity for the development of optically pure colours. In this study, a replacement for potentially toxic colorants has been sought through the use of a rare earth metal ion, cerium. Appropriate doping of cerium oxides with molybdenum and iron gives an orange–red colorant. The conditions ideal for optimal colour have been standardised and the resultant colorant characterised through powder X-ray diffraction techniques, particle size measurement, etc. The colorants exhibit good hiding power and tinting strength.  相似文献   

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