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The paper aims to analyse the effect of acid hydrolysis on the chemical composition and the biological activities of Rubia tinctorum collected from the south of Tunisia. It proposes to clarify the relationship between alizarin content and the antioxidant and antimicrobial activities of Rubia extract.

The paper opted for analytical tools (HPLC) and the in-vitro study of biological activities, namely, the antioxidant activity which is evaluated using the radical scavenging assay (ABTS) and ferric reducing power assay (FRAP); the antimicrobial activity is tested using the wells agar diffusion method.

The paper provides information about the positive effect of acid hydrolysis, namely, the enhancement of alizarin content in the extract which has increased its antioxidant and antimicrobial activities.

This paper fulfils an identified need to study the relationship between the chemical composition, biological activities and colour enhancement.

Identification and characterization of organic pigments and dyes used in works of art and cultural heritage material such as prints, drawings, manuscripts, paintings, and textiles can provide important information for dating, authentication, and conservation treatment of these objects and studying art history in general. Applications of surface‐enhanced Raman scattering (SERS) for this purpose have recently attracted increasing attention of both academic scientists and museum researchers. This paper aims to review the latest development involving the emerging applications of SERS for the analysis of organic pigments and dyes used in works of art and cultural heritage material.

First, the importance of organic pigments and dyes in the studies of works of art and cultural heritage material and the challenges in their identification and characterization are briefly summarized. This is followed by a discussion on sampling considerations in the context of art and archaeology. Then the fundamental principle of SERS, SERS instrumentation and different types of SERS substrates are reviewed. Finally, selected examples of SERS applications to the identification of organic pigments and dyes, including the analysis of a couple of samples of artistic and archaeological interest, are presented and discussed.

The last few years have witnessed the emergence of SERS as a non‐destructive or micro‐destructive technique for the characterization of organic pigments and dyes found in artistic and archaeological objects. Spectroscopic and microscopic measurements using SERS have provided some novel information and answers to a wide variety of questions. However, SERS application to the field of art and archaeology is still in the fledging stage of development and requires closer collaboration between academic scientists and museum researchers. But the range of possible applications is broad. Future trends point to a strong need for the development of portable instruments for field applications.

By compiling this review, the authors hope to direct more attention toward SERS and bring together the expertise in the scientific, museum and art community to further explore the possibilities of SERS in rapid and direct identification of pigments and dyes under field conditions.

In this chapter, a situation analysis was made on the use of technology in gastronomy, an ever-growing and exciting research area. The use of technology is essential in food production processes as well as in all sectors, and accordingly, the number of research on the subject has increased in recent years. Therefore, in the study, information is also given about trend applications today in addition to the use of technology in gastronomy. It is aimed to present the studies conducted by different disciplines together, to reveal the current situation in the light of the studies carried out on a national and international scale and to support possible future studies.

The present study has employed a high performance liquid chromatographic method coupled with a diode array detector (HPLC-DAD) to identify the dyestuffs in textile samples collected from the Coptic Museum in Cairo and the Museum of Jordanian Heritage. The results indicate that mixtures of organic dyes are used in dyeing these samples to produce different colours. The most dominantly identified colourants in samples collected from the Museum of Jordanian Heritage are laccaic acid, kermesic acid, munjistin and indigotin. The most dominantly identified dyestuffs are lac dye (Kerria lacca, Kerr), kermes (Kermes vermilio), madder (Rubia) species and indigoid dye source, either indigo (Indigofera species) or woad (Isatis tinctoria L.). These results confirm the historical information in the Museum of Jordanian Heritage in that the tested textile objects date back to the end of the 19^th century or the beginning of the 20^th century. The most dominantly identified colourants in samples collected from the Coptic Museum are alizarin, purpurin, and indigotin. The most dominantly identified dyestuffs are madder and indigotin. Based on this investigation, it is concluded that the tested dyed samples collected from the Coptic Museum belong to the 6-7^th centuries. This conclusion is in agreement with the initial dating of samples according to the style of the decorations.

The law relating to foreign bodies in food and drink continues to grow in volume, if not in clarity. It is generally accepted that their presence may constitute an infringement of Section 2, Food and Drugs Act, 1955; that dust (or cement or paint or any other extraneous matter) adhering to the interior of a bottle means that the bottle is not clean within the meaning of regulation 27 (1), Milk and Dairies Regulations, 1959 or regulation 6 (2), Food Hygiene Regulations, 1960. This has been held to be so even if the dust (or other adherent substance) has been shown to be sterile. In Jones v. Bryn Dairy, Ltd., (1954), Q.B.D., a case under the Milk and Dairies Regulations, 1949 where the offence concerned dust adhering to the interior of a bottle of milk, Lord Goddard made the robust statement of the obvious—“clean means clean”—and rejected the argument that the bottle which contained the very small quantity of dust was clean because the dust itself was sterile. It had yet to be decided that similar considerations applied to a foreign body lying loose in the bottle; that such a bottle of milk was not in a state of thorough cleanliness before use. The decision of the Divisional Court in South Coast Dairies Ltd. v. Halstead (1963), (reported in December, 1963 issue of B.F.J.,) has now done this.

This paper aims to focus on the absorption behaviour of single and binary mixtures of natural dyes on wool. Natural dyes are multi-components with different structures and properties.

In this research, the absorption behaviour of single and binary mixtures of natural dyes was investigated on wool fibre. Study was conducted via some natural dyes, including pomegranate peel as a yellow natural dye with tannin, weld as a yellow natural dye without tannin and madder as a red natural dye without tannin. Applied mordant was alum, which was used in the pre-mordant method. Different shades were obtained by varying dye concentration in the binary mixture. The effect of tannin on absorption behaviour of binary mixture of natural dyes was investigated by spectral reflectance and colour parameters of dyed samples measurements.

Obtained results indicate that tannin affects the absorption behaviour of natural dyes in binary mixtures.

Because natural dyes are multi-components with different structure and properties, the study of compatibility and absorption behaviour of natural dyes in binary mixture on wool is important in applied researches.

The study of compatibility and absorption behaviour of binary mixture of natural dyes on wool is novel.

The purpose of this paper is to develop textile materials with a pH‐sensitive function.

As a start point, the feasibility of incorporating pH‐indicators in conventional textiles using standard dyeing processes was investigated. Next, a pH‐indicator was incorporated into a nylon nanofibrous structure by adding the dye to the polymer solution before the start of the electro‐spinning process.

The authors' results proved that it is possible to develop a pH‐sensor using conventional textiles dyed by a standard dyeing process. Also, the incorporation of a pH‐indicator dye into a nanofibrous structure was possible. Moreover, reproducible samples could be obtained. Furthermore, the majority of the obtained textile structures showed a clear colour change with a change in acidity. This halochromic behaviour was, however, different from the behaviour of the dyes in solution due to dye‐fibre interactions.

The knowledge obtained in this study can lead to the development of a textile pH‐sensor. This sensor can be used in a broad field of applications since a colour change is a non‐disturbing but clear signal which can perform a first warning function.

RAILS AND WHEELS OF LARGE CRANES ARE, DURING LONG TRAVEL MOVEMENT, ALWAYS SUBJECTED TO LATERAL PRESSURES WHICH LEAD TO CONSIDERABLE WEAR OF RAIL AND WHEEL FLANGES. By eliminating dry friction on these parts, the new CENTRALUBE Crane Rail Lubricator (De Limon system) obviates lengthy out‐of‐service periods during repair and saves working hours and cost spent on such repairs.

Everyone is extremely concerned about environmental protection and health safety due to the rise in living standards. Plant-derived natural dyes have garnered much industrial attention in food, pharmaceutical, textile, cosmetics, etc. owing to their health and environmental benefits. The present study aims to focus on the elimination of the use of synthetic dyes and provides brief information about natural dyes, their sources, extraction procedures with characterization and various advantages and disadvantages.

In producing natural colors, extraction and purification are essential steps. Various conventional methods used till date have a low yield, as these consume a lot of solvent volume, time, labor and energy or may destroy the coloring behavior of the actual molecules. The establishment of proper characterization and certification protocols for natural dyes would improve the yielding of natural dyes and benefit both producers and users.

However, scientists have found modern extraction methods to obtain maximum color yield. They are also modifying the fabric surface to appraise its uptake behavior of color. Various extraction techniques such as solvent, aqueous, enzymatic and fermentation and extraction with microwave or ultrasonic energy, supercritical fluid extraction and alkaline or acid extraction are currently available for these natural dyes and are summarized in the present review article.

If natural dye availability can be increased by the different extraction measures and the cost of purified dyes can be brought down with a proper certification mechanism, there is a wide scope for the adoption of these dyes by small-scale dyeing units.

Natural dyes are mostly used for dyeing of natural fibre textiles to improve their eco-friendly features. For successful commercial use of natural dyes, the appropriate and standardized dyeing techniques need to be adopted. Appropriate scientific techniques or procedures need to be derived from scientific studies on dyeing methods, dyeing process variables, dyeing kinetics and compatibility of selective natural dyes with minimal use of hazardous chemicals.

In the present study, different enzymes (protease, amylase, xylanase, pectinase, phytase) were used efficiently with Rubia dye by using simultaneous and two-step processes; both the processes were developed with an aim for conservation of time and energy, for the ease of industrial use. The highlights of the study are twofold: eco-friendly natural dyeing by using enzyme replacing metal mordant and room temperature dyeing, which is a completely new concept.

Experiments showed that enzymatic treatment can give good colour strength to silk fabric using Rubia as a dye source and has good potential for commercial dyeing. It is a non-toxic dye. Use of enzymes were a deliberate attempt to avoid metal mordanting in silk dyeing, as it would make textile dyeing eco-friendlier. The order of reactivity of enzymes in one-step process was found to be protease > phytase > xylanase > amylase > pectinase. Similarly, for two-step dyeing process, the order of reactivity of enzymes observed was protease > amylase > xylanase = pectinase > phytase. Protease enzyme was the best option in both the cases. Overall, it can be concluded that in the case of enzymatic treatment, the two-step process was better in terms of larger K/S values, colour coordinate values and dye adherence.

A new domain of room temperature dyeing technique has been introduced.

In the present study, different enzymes (protease, amylase, xylanase, pectinase, phytase) were used efficiently with Rubia dye by using simultaneous and two-step processes; both the processes were developed with an aim for conservation of time and energy, for the ease of industrial use. The highlights of the research are twofold: eco-friendly natural dyeing by using enzyme replacing metal mordant and room temperature dyeing, which is a completely new concept. Overall, the ease of use for industrial application. Rubia dye from Sri Lanka has been used in conjunction with different enzymes to show that metal mordanting can be easily replaced by the use of eco-friendly and biodegradable enzymes. The most attractive feature of this study is the low-temperature dyeing at 30-40°C. For any dyeing house, this process can be easily adapted on jigger, winch or even in continuous padding machine. Good fastness properties and dye adherence have been the other highlights of this study.