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The demise of the CFC‐113/alcohol azeotropic solvent for de‐fluxing circuit assemblies after soldering has led, in recent years, to the electronics assembly industry being offered other cleaning technologies, some new and some new to this industry. In terms of uptake, one of the most successful will be semi‐aqueous cleaning involving the use of an organic solvent of low volatility to dissolve the contamination followed by an aqueous rinsing process. Two families of solvent have evolved based on natural products (terpenes) and synthetic hydrocarbon chemicals. This paper reviews the possible semi‐aqueous processes and the development of the solvents that has taken place. The cleaning performance is considered as well as the potential for effluent control and fully closed‐loop systems.

This is a review paper, covering the various concerns that the electronics manufacturing industries are currently addressing, except for semiconductor manufacturing. These include waste water treatment, the need to reduce energy requirements for both the finished product and the manufacturing processes, the use of lead in solder and cathode ray tubes, bromine‐based fire retardants, ozone depletion, including the problems of the small and medium industry in developing nations and new ozone‐depleting solvents, climate change due to fluorocarbons and the problems from volatile organic compounds. A section treats the impact of industrial pollution on public health. The paper is written in a very critical style, evoking problems due to inappropriate rule making.

The purpose of this paper is to investigate some novel bis‐hetaryl dyes containing both azo and azo methine chromophores on their molecular structures: two series of different molecular structures of these dyes were synthesised. The spectral characteristics and the relationships between colour and constitution of these dyes in solvents with different polarities were systematically investigated and discussed.

A series of novel bichromophoric dyes containing azo and azomethine chromophores were synthesized using two kinds of reaction routes. 2‐amino‐4‐(p‐substituted) phenyl‐thiazole derivatives, which are coupling components, were subjected to diazotisation with aniline derivatives and then to condensation with benzaldehyde derivatives. By exchanging the synthesis route, two series of bichromophoric dyes could be obtained.

The maximum absorption wavelengths of the obtained dyes would be attributed to the higher bathochromic shift in basic organic solvent with high polarity, such as dimethylformamide, as compared with the solvent with low polarity, such as chloroform.

In the present study, a series of novel bichromophoric dyes were synthesized by means of two‐step pathway. In addition, the effects of substituent on the primary aromatic amine and on benzaldehyde moieties will also be discussed.

This novel synthesis method of the thiazole ring would lead to the formation of 2‐amino‐4‐(p‐substituted)phenyl‐thiazole with heteroaromatic coupling component position at C‐5, and consequently would produce the heteroaromatic diazo component at C‐2 for the preparation of the heteroaryl diazo dyes.

In this paper, the bichromophoric dyes obtained by different synthesis routes would indicate that the effect of solvent polarity should be responsible for the bathochromic shifts of the dyes.

Powder coating in the car industry. “The future for powder coatings in the car industry is bright”, Chrysler Corporation's Ernie McLaughlin said in the keynote address at the recent Powder Coating '94 in Cincinnati.

Inorganic thickeners or thixotropic agents are marketed in powder, fibrous or paste form. Chemically, they can be divided into the following groups:

Reports on the determination of rates of electropolishing of copper by measuring the limiting current of anodic dissolution of copper in phosphoric acid and in (water‐acetone) ‐phosphoric acid mixtures. Notes that the rate of electropolishing is decreased in (water‐acetone) ‐phosphoric acid mixtures and that the percentage inhibition of dissolution depends on the mole fraction of acetone, and its dielectric constant. Concludes with calculation of the thermodynamic parameters of activation.

The study aims to describe the main classes of antioxidants existing in fruit, beverages, vegetables and herbs and the different extraction and application of antioxidants in food. Oxidative degradation of lipids, especially induced by reactive oxygen species, leads to quality deterioration of foods and cosmetics and could have harmful effects on health. A major challenge is to develop tools to assess the antioxidant capacity and real efficacy of these molecules. Recently, many review papers regarding antioxidants from different sources and different extraction and quantification procedures have been published. However, none of them has all the information regarding antioxidants (sources, extraction and application in food).

This paper tries to take a different perspective on antioxidants for the new researcher involved in this field.

Antioxidants from fruit, vegetables and beverages play an important role in human health, for example, preventing cancer and cardiovascular diseases and lowering the incidence of different diseases. A number of plant products act as scavengers of free radical species and so have been classified as antioxidants. Antioxidants are an important group of food additives that have the ability to protect against detrimental change of oxidizable nutrients and consequently they extend shelf-life of foods.

Most of the antioxidants present in foods are phenolic and polyphenolic compounds, but their efficacy in food for the prevention of oxidation or in the body for dealing with oxidative stress and its consequences depends on different factors.

This study collected the last finding in the field of sources and applications of natural antioxidants.

Thixotropy can be regarded as the loss of viscosity in a paint or other material that is brought about by mechanical agitation, and where the viscosity continues to decrease provided that this disturbance is continued for a period of time. Conversely, when the mechanical force is removed, the material then increases in viscosity and this recovery toward the initial structure continues to take place over a period of time. Sometimes the time dependency of the viscosity is vanishingly small so that the material is then properly referred to as pseudoplastic. In most of the literature, however, it is not usually possible to differentiate between thixotropy and true pseudoplasticity and therefore both kinds of structure are included in this review as they each are destroyed by mechanical agitation and recover when this is discontinued.

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.

The amount of food wasted every year is 1.3 billion metric tonne (MT), out of which 0.5 billion MT is contributed by the fruits processing industries. The waste includes by-products such as peels, pomace and seeds and is a good source of bioactive compounds like phenolic compounds, flavonoids, pectin lipids and dietary fibres. Hence, the purpose of the present study is to review the novel extraction techniques used for the extraction of the bio active compounds from food waste for the selection of suitable extraction method.

Novel extraction techniques such as ultrasound-assisted extraction, microwave-assisted extraction, enzyme-assisted extraction, supercritical fluid extraction, pulsed electric field extraction and pressurized liquid extraction have emerged to overcome the drawbacks and constraints of conventional extraction techniques. Hence, this study is focussed on novel extraction techniques, their limitations and optimization for the extraction of bioactive compounds from fruit and vegetable waste.

This study presents a comprehensive review on the novel extraction processes that have been adopted for the extraction of bioactive compounds from food waste. This paper also summarizes bioactive compounds' optimum extraction condition from various food waste using novel extraction techniques.

Food waste is rich in bioactive compounds, and its efficient extraction may add value to the food processing industries. Hence, compressive analysis is needed to overcome the problem associated with the extraction and selection of suitable extraction techniques.

Selection of a suitable extraction method will not only add value to food waste but also reduce waste dumping and the cost of bioactive compounds.

This paper presents the research progress on the extraction of bioactive active compounds from food waste using novel extraction techniques.