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Any change in physical performance of the fibre corresponds to a change in its molecular structure. Basically polyester is hydrophobic in nature due to the absence of attracting polar groups and the dense packing in its polymeric structure. Due to the dense packing in polymeric structure and lack of hydroxyl groups of polyester it does not absorb water hence breathability is poor. The possibility of using air and oxygen plasma treatments for fibre surface activation to facilitate the improvement of hydrophilicity is attempted and has been improved. The purpose of this paper is to study the possibility of engineering the multifunctional of fabrics.

The treated fabric is evaluated through measuring the ultraviolet protection factor, thermal resistance, and antibacterial activity properties. Scanning electron microscopy and transmission electron microscopy graphs show deposition of nano particles (NPs) of Chitosan, TiO₂ and ZnO onto the fibre after washing several times.

Air plasma-nano Chitosan treatment affects positively the antibacterial activity, thermal resistance of the fibre and air plasma-nano TiO₂ and ZnO the fibre protection against ultraviolet rays. Furthermore, the plasma treatment solves an environmental problem which offers safe production process and working place and decreases the unit cost.

The authors are confident that textiles will adopt this technology in the future.

Chlorofluorocarbons, better known as CFCs, were developed more than 50 years ago as safe alternatives to the unpleasant sulphur dioxode and ammonia then in use in refrigerator compressors.

The purpose of this paper is to evaluate the potential of natural colourants from fruits of Ixora siamensis for coating applications, to study its glossiness and effectiveness against UV‐B irradiation.

In this study, natural colourants from the fruits of Ixora siamensis were extracted using trifluoroacetic acid‐methanol solution. Anthocyanins and organic acid variants were mixed together to form co‐pigments. Different concentrations of ferulic and gallic acid co‐pigments were added to a blended solution of poly (vinyl alcohol), PVA and anthocyanin (from Ixora siamensis) to form a coating system. The coatings were exposed to UV‐B irradiation at room temperature in air using a UV‐lamp which emitted radiation at 312 nm. The effects of UV‐B irradiation on the coating system were evaluated using glossiness test and UV‐visible spectroscopy.

Anthocyanins are unstable and can quickly lose their colour. One of the methods of preserving the stability of these pigments is by co‐pigmentation. Co‐pigmentation of anthocyanin with organic acid variants resulted in an increase in both hyperchromic effects (ΔA) and bathochromic shifts (Δλ). In this study, ferulic acids yielded better results compared to gallic acids.

Samples with co‐pigmentation give better result compared to the untreated samples. The addition of 0.5 and 1.0 per cent ferulic acid improves the gloss properties and resistivity of the samples towards the UV irradiation. Thus, in order to study the effectiveness of ferulic acid as additive and improving the properties of the samples, the percentage of ferulic acid added and exposure time could be increased.

The method developed provided a simple and efficient solution for improving the UV resistance of anthocyanin blend with poly (vinyl alcohol), PVA UV absorber. Effect of ferulic acid as UV absorber, if added in more concentration, can be further studied for optimization.

The social implication is the use of local plant species as a low cost source of natural pigments in coating system.

The method for improving the resistance towards UV irradiation of anthocyanin blend with poly (vinyl alcohol), PVA was novel and could find numerous applications for natural product based on plant pigment.

The purpose of this study is to investigate the effects of pH, UV-B radiation and NaCl on anthocyanin extracted from vivid blue petals of Clitoria ternatea L. (legume crop), as a potential natural colourant for food, dye or coating technology.

The anthocyanin from petals of Clitoria ternatea was extracted using 0.5 per cent trifluroacetic (TFA) in methanol solution. The liquid colourant was exposed to different pH (1, 4.5 and 5.5), UV-B radiation and sodium chloride (NaCl). The results were compared using UV-vis spectrophotometric analysis.

Anthocyanins are sensitive and quickly degrade in the presence of light. In the dry powder form, the anthocyanin is easier to maintain and preserve (storage).

Anthocyanins extracted from vivid blue petals of Clitoria ternatea L. are sensitive and quickly degrade in the presence of light.

The anthocyanin pigments extracted from Clitoria ternatea L. petals with methanolic acid were successfully coated on glass slides. The combination of binders and pigments had produced environmental paint which added with stabilisers (additives) for better durability. Acrylic has been known for its high weathering and embrittlement resistance, good mechanical and electrochemical properties and gloss retention.

This anthocyanin is suitable as natural colourant especially in baby products, cosmetics production or for coating and varnish application.

Till date, the natural colourant of Clitoria ternatea L. petals is widely used in food. However, this result is a new finding, as there is no report on the potential of applications of this natural colourant for coating technology. Therefore, the current study with appropriate extraction method was significantly based on the relevant literatures of coating production from pigment by using other plant species. The findings and conclusion highlight the practicality as the potential applications in coating technology.

This study aims to determine the appropriate irradiation dose for induction of somaclonal variation in mass of unorganized parenchyma cells derived from sainfoin (Onobrychis viciifolia) tissues.

To investigate the feasibility of UV-B irradiation (312 nm), seeds and callus of sainfoin were exposed to five different intensities (20-100 per cent) for evaluating the effectiveness of phytochemical constituents and cellular behaviour.

Although percentage of seed viability reduced in 20 per cent intensity of UV-B irradiation compared with control seeds, the germination speed significantly enhanced from 3.58 to 5.42. The spectrophotometer analysis confirmed that concentrations of chlorophyll (a and b) decreased after UV-B exposure as compared with control callus. Also, carotenoid content showed significant differences among treated calli. Flavonoid and phenolic contents were observed to gradually increase when the non-irradiated callus subjected to 40 and 60 per cent intensities of UV-B irradiation, respectively. Observation on cellular behaviour such as determination of nuclear and cell areas, mitotic index and chromosomal aberrations were also detected to change in different intensities of UV-B irradiation. Fragmented and aneuploidy aberrations were only observed in exposed cells with more than 40 per cent intensity of UV-B irradiation.

In reality, radiocytological evaluation was proven to be essential in deducing the effectiveness of UV-B irradiation to induce somaclonal variation in callus tissue of sainfoin.

The flux residues on almost all soldered printed circuit boards are removed using the chlorofluorocarbon (CFC) 113. In just one year's time production of this solvent will almost certainly be curtailed, on a scale agreed internationally. This is a major issue that needs to be addressed urgently by the electronics assembly industry worldwide. This paper presents (i) the background that has led to the restrictions being placed on production and consumption of solvent 113, (ii) the international agreement and timetable for the implementation of the restrictions and (iii) the perceived opportunities that are available to the electronics assembly industry to meet this challenge.

Provides a summary of the main European regional and world global issues in relation to air pollution. Makes reference to the classical problems of SO⊂x, SPM and NO⊂x pollution by heavy metals, and to the issue which was at the forefront in the 1980s – acidic deposition; winter‐and summer‐smog episodes which caught the attention of politicians a few years ago; and of course, the widely spoken of issue on global climate change and the ozone layer depletion. Gives special attention to the not so well‐recognized and understood indoor air quality. Closes with the proposal of possible solutions for confronting the various issues.

Discusses the responses of plants to a variety of environmental stresses and considers different techniques that could potentially be used to detect and amplify such responses. Because plants may naturally produce steroids in response to raised stress levels, the paper suggests that genetic modification of crop plants to improve resistance to stress is worth investigating as a strategy. Sensitive to public concerns about the safety of transgenic crops, the authors suggest using such plants in carefully controlled locations.

The worldwide production and the consumption of CFCs are now controlled through the Montreal Protocol. A meeting in London in June 1990 of the signatories of the Protocol will almost certainly tighten the controls on CFCs and introduce regulations to control other common chlorinated solvents. This paper gives the reasons why worldwide control of emissions of chlorinated substances is necessary, the events that led up to the present controls and the prognosis for future regulations. The properties and uses of the six key chlorinated solvents are discussed. Each industrial solvent‐using sector has a range of options available to implement cutbacks and eventual elimination of chlorinated solvents.

The purpose of this paper is to access the present situation of the Pakistani population that suffers from vitamin D deficiency.

A review-based study was conducted based on publications from Pakistan between the years 2008 and 2018. The publications were archived from Pub Med and Google Scholar databases. A total of 18 publications were shortlisted, based on the cutoff values of vitamin D sufficiency, insufficiency and deficiency.

As per the data, 38.5 per cent of the participants were males, 48.7 per cent were females and 12.8 per cent of the studies have not mentioned the genders of the participants. The cumulative results show that 58.17 per cent (95 per cent CI: 52.17, 64.16) of the population is vitamin D-deficient and 26.65 per cent (95 per cent CI: 21.63, 31.66) is insufficient in vitamin D. The highest level of vitamin D deficiency was reported from Sindh (62.15 per cent), followed by Khyber Pakhtunkhwa (60.57 per cent), Punjab (51.75 per cent) and the Federal Capital (49.25 per cent). Moreover, Cochran’s Q test indicated considerable heterogeneity (p = >0.001) with regard to Vitamin D deficiency (VDD) prevalence found among samples from the selected studies.

The present analysis suggests that more than half of the Pakistani population suffers from VDD, which, thus, should be considered as an epidemic and treated likewise.