Search results

1 – 10 of 30
To view the access options for this content please click here
Article
Publication date: 3 July 2017

Rui Huang, Kangni Shen, Teng Xu and Yongjia Shen

The purpose of this paper is to explore the optic performance of extended stilbene derivative.

Abstract

Purpose

The purpose of this paper is to explore the optic performance of extended stilbene derivative.

Design/methodology/approach

Five steps were adopted to synthesise novel 4, 4′-bis (2-cyanostyryl) stilbene, which contained three vinyl units in the skeleton (S3E). The structure of S3E was characterised by 1H NMR and EI-MS. Its absorption and emission spectra were also given.

Findings

Compared to C.I. Fluorescent Brightener 199, which contains two vinyl units in the skeleton, S3E showed obvious bathochromic shifts in both UV-VIS and FL spectra. The maximum absorption wavelength and fluorescent wavelength were at 390 nm and 464 nm, respectively, with Stoke’s shift of 74 nm. The absolute fluorescence quantum yield was 0.42. Thermogravimetric analysis (TGA) revealed that the weight loss of S3E was less than 5 per cent at 300 °C. Moreover, the light resistance test showed that S3E in PVC plate can keep the good fluorescent intensity for more than seven days exposed to xenon light. Therefore, it is believed that S3E could satisfy the requirements of colouring PVC as a fluorescent dye.

Practical implications

S3E can be used as a candidate of fluorescent dye in the development of thermoplastics.

Originality/value

The present paper designed and synthesised a new derivative of stilbene, which showed its preference to be a colourant of thermoplastics.

Details

Pigment & Resin Technology, vol. 46 no. 4
Type: Research Article
ISSN: 0369-9420

Keywords

To view the access options for this content please click here
Article
Publication date: 10 August 2018

Esmail Rezaei-Seresht, Aboulfazl Salimi and Behnam Mahdavi

The purpose of this paper is synthesis and evaluation of antioxidant and antibacterial activities of a series of new azo dyes derived from 4-aminostilbene.

Abstract

Purpose

The purpose of this paper is synthesis and evaluation of antioxidant and antibacterial activities of a series of new azo dyes derived from 4-aminostilbene.

Design/methodology/approach

First, the starting material 4-aminostilbene was prepared via two successive Wittig and reduction reactions from 4-nitrobenzyl bromide. The obtained 4-aminostilbene was then reacted with some phenols under the normal azo coupling reaction conditions to give five new azo products. Antioxidant activity of the azo compounds was determined by radical scavenging assay using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical. Also, the antimicrobial activity of the compounds against one gram-positive and eight gram-negative strains was evaluated based on the inhibition zone using disc diffusion assay.

Findings

The structures of the azo dyes were identified and characterized by fourier-transform Infrared, 1H nuclear magnetic resonance (NMR) and ultraviolet-visible (UV-V) is spectroscopic methods. All the compounds showed higher antioxidant activity than ascorbic acid (Asc) and butylated hydroxytoluene (BHT) as positive controls. Moreover, the compounds showed lower antibacterial activity than the standard antibiotic vancomycin.

Research limitations/implications

Excellent antioxidant activity, along with antibacterial activity against Streptococcus pneumoniae and Pseudomonas aeruginosa, was observed for the two synthesized azo dyes.

Originality/value

Five novel azo dyes based on 4-aminostilbene were synthesized. The dyes have a highly p-extended conjugated structure comprising the phenolic and stilbenic segments, and they indicated good antioxidant activity, so that the two dyes (2c and 2d) even showed much more scavenging activity compared to BHT which is used as an antioxidant agent in food industries. These compounds with highest antioxidant activity also inhibited the growth of S. pneumoniae and P. aeruginosa.

Details

Pigment & Resin Technology, vol. 48 no. 1
Type: Research Article
ISSN: 0369-9420

Keywords

To view the access options for this content please click here
Article
Publication date: 1 March 1950

B.C. VICKERY

An index, as the Shorter Oxford English Dictionary puts it, is ‘that which serves to direct to a particular fact or conclusion’. Its first purpose is to indicate the…

Abstract

An index, as the Shorter Oxford English Dictionary puts it, is ‘that which serves to direct to a particular fact or conclusion’. Its first purpose is to indicate the existence and the location of every item of information in the field it is designed to cover. Its mission is to establish contact between searcher and information sought, exactly, exhaustively, and expeditiously.

Details

Journal of Documentation, vol. 6 no. 3
Type: Research Article
ISSN: 0022-0418

To view the access options for this content please click here
Article
Publication date: 1 March 1981

In a full blaze of comings and goings, it is unnecessary to remind ourselves that the holiday season is upon us; mass travel to faraway places. The media have for months…

Abstract

In a full blaze of comings and goings, it is unnecessary to remind ourselves that the holiday season is upon us; mass travel to faraway places. The media have for months, all through the winter, been extolling a surfeit of romantic areas of the world, exspecially on television; of colourful scenes, exotic beauties, brilliant sunshine everywhere; travel mostly by air as so‐called package tours — holidays for the masses! The most popular areas are countries of the Mediterranean littoral, from Israel to Spain, North Africa, the Adriatic, but of recent years, much farhter afield, India, South‐east Asia and increasingly to the USA.

Details

British Food Journal, vol. 83 no. 3
Type: Research Article
ISSN: 0007-070X

To view the access options for this content please click here
Article
Publication date: 21 March 2008

G.A. Baghaffar, A.M. Asiri, B.M. Babgi and M.S. Al‐Amoudi

To discuss synthesis and evaluation of organo‐metallic chalcones as second‐order nonlinear optical (SONLO) materials.

Abstract

Purpose

To discuss synthesis and evaluation of organo‐metallic chalcones as second‐order nonlinear optical (SONLO) materials.

Design/methodology/approach

The new chalcones have been synthesised via Knovoenagel reactions of ferrocen carboxaldehyde with two active methylene compounds.

Findings

The ferrocenyl chalcones prepared have shown bathochromic shift and thermal stability in polymeric film. On heating the dye films up to 80°C the extent of degradation reached up to 12 per cent and very small amount of degradation was observed at 43 and 60°C.

Originality/value

The paper shows that these compounds have UV‐Vis bathochromic shift, enabling them to be used as SONLO materials in the blue domain as well as dyes.

Details

Pigment & Resin Technology, vol. 37 no. 2
Type: Research Article
ISSN: 0369-9420

Keywords

To view the access options for this content please click here
Article
Publication date: 1 September 2006

A.M. Asiri and M.S. Al‐Amoudi

To discuss synthesis and evaluation of organo‐metallic dyes as second‐order nonlinear optical (SONLO) material.

Abstract

Purpose

To discuss synthesis and evaluation of organo‐metallic dyes as second‐order nonlinear optical (SONLO) material.

Design/methodology/approach

New dyes have been synthesised via Knovoenagel reactions of ferrocene carboxyaldehyde and two active methylene compounds.

Findings

The ferrocenyl dyes prepared have shown bathochromic shift and thermal stability.

Practical implications

These compounds have UV‐Vis bathochromic shift, enabling them to be used as SONLO materials as well as dyes.

Originality/value

The paper provides further information on the thermal studies of these types of molecules.

Details

Pigment & Resin Technology, vol. 35 no. 5
Type: Research Article
ISSN: 0369-9420

Keywords

To view the access options for this content please click here
Article
Publication date: 16 January 2020

Juliane Barroso Leal, Juçara Barroso Leal, Joaline Barroso Portela Leal, Yan de Lima Borges, Maria Ivone Leal de Moura, Alfredo Anderson Teixeira-Araujo, Venilson Serafim da Costa and Ferdinando Oliveira Carvalho

This paper aims to verify the effect of 12 weeks of grape juice (GJ) consumption associated with aerobic exercise on the variation of the hypertensive elderly pressure.

Abstract

Purpose

This paper aims to verify the effect of 12 weeks of grape juice (GJ) consumption associated with aerobic exercise on the variation of the hypertensive elderly pressure.

Design/methodology/approach

A total of 45 hypertensive elderly of both sexes were distributed into: control group (CG, n = 10), exercise group (EG, n = 10), juice group (JG, n = 12) and juice and exercise group (JEG, n = 13). Blood pressure and heart rate were checked weekly before exercise in JG and JEG, and before and after intervention in all groups, with JG and JEG supplemented with 200 mL of GJ. Three weekly sessions of moderate walking were applied.

Findings

There was a reduction in EG, JG and JEG for systolic pressure and diastolic only for JG and JEG. The GJ consumption to the practice of aerobic exercise provided reductions in the arterial pressure of hypertensive, in addition to stabilization of the diastolic pressure.

Research limitations/implications

Although the objective of the study was to compare the effect and value of intervention with controls, the study had no intervention in food consumption, which could have led to more significant results. There was a limitation in the control drink, leading the study not to be blind, which may have impaired the results. However, it is probably not a bias, as the groups were divided by residence area, and therefore, had no direct contact with the other groups. Another limitation was that the sample size was still small, which would lead to more reliable results. Finally, although the existing limitations cannot be disregarded, the results of this research are very promising, especially when the objective is the effect of GJ and aerobic exercise on blood pressure, with the possibility of implementing supplemental GJ and the inclusion or not of exercise to the hypertensive elderly.

Originality/value

The paper deals with the benefits of GJ consumption associated with aerobic physical exercise on the blood pressure of elderly hypertensive patients. Considering that GJ along with physical exercise was enough to reduce the blood pressure of hypertensive elderly, this may be a new model to be used to reduce and/or control blood pressure, and GJ and the exercise to be part of the daily life of the population.

Details

Nutrition & Food Science , vol. 50 no. 5
Type: Research Article
ISSN: 0034-6659

Keywords

To view the access options for this content please click here
Article
Publication date: 29 October 2019

Mariantonietta Fiore, Leonardo Salvatore Alaimo and Nino Chkhartishvil

Wine, fruits, vegetables and whole grains are the main products of a healthy diet. The purpose of this paper is to scrutinize the existence of an interesting and evocative…

Abstract

Purpose

Wine, fruits, vegetables and whole grains are the main products of a healthy diet. The purpose of this paper is to scrutinize the existence of an interesting and evocative bond among moderate intake of wine, health and well-being.

Design/methodology/approach

By means of a fuzzy cluster analysis, the authors try to investigate the existence of groups of regions similar in wine consumption, subjective well-being, health and social relations. The latter are expressed through composite indicators, built and developed by Istat within the Italy ESW project’s activities (equitable and sustainable well-being). The analysis also investigates how this link has evolved over time. Data are related to refer to the situations in 2010 and 2017 in 21 regions of Italy.

Findings

Results obtained in 2010 seem to confirm the hypothesis of the existence of a link among moderate wine consumption, hedonism well-being and health, and in addition, findings highlight the so-called North‒South gap, that is the strong differences and economic issues among the different areas of the country. Then, outcomes obtained for 2017 appear in line with 2010 results.

Originality/value

Several authors from medicine, economics and chemistry domain strongly suggest and demonstrate that regular and moderate intake of wine reduces the incidence of heart disease, diabetes mellitus and hormonal problems, and correlatively increases longevity. In this work, the authors develop further research step including the aspects related to personal well-being and social relations under the umbrella of a hedonism approach. Finally, results highlight the existence of an amazing tie among moderate intake of wine consumption, well-being and health.

Details

British Food Journal, vol. 122 no. 8
Type: Research Article
ISSN: 0007-070X

Keywords

To view the access options for this content please click here
Article
Publication date: 8 February 2008

C.A. Smith

The purpose of this paper is to discuss the chemistry of organic compounds with a liquid crystal phase and their application in flat panel electronic displays.

Abstract

Purpose

The purpose of this paper is to discuss the chemistry of organic compounds with a liquid crystal phase and their application in flat panel electronic displays.

Design/methodology/approach

The paper is a review of liquid crystal display (LCD) technology. It provides an introduction to liquid crystals and LCDs, with an emphasis on their historical development, various LCD technologies employed, their electronic interconnection to driver circuitry and failure analysis.

Findings

The current world market for LCDs is being driven by flat panel television sales. As well as their use in television sets, they are to be found in aircraft cockpit instrumentation, computer monitors, mobile phones and digital cameras, all of which would not exist in their present form without liquid crystals.

Originality/value

The paper provides an introduction to LCDs for electronic engineers working in this area, who may be unfamiliar with the chemistry of liquid crystals, LCD technology, electronic interconnection and failure analysis.

Details

Circuit World, vol. 34 no. 1
Type: Research Article
ISSN: 0305-6120

Keywords

To view the access options for this content please click here
Article
Publication date: 1 August 1989

D.P. Atkins and S.M. Smith

The scientific basis of MAFF′s policy on the chemical safety offood is described. Examples are provided of the independent advisorycommittee structure which depends on…

Abstract

The scientific basis of MAFF′s policy on the chemical safety of food is described. Examples are provided of the independent advisory committee structure which depends on scientific information and advice in formulating proposals to Government. This science takes the form of pre‐market evaluations of chemical products such as food additives, pesticides and veterinary products and subsequently extends to the monitoring of their presence in the diet as part of a wide‐ranging surveillance programme of the UK′s food supply for food additives, nutrients and contaminants.

Details

British Food Journal, vol. 91 no. 8
Type: Research Article
ISSN: 0007-070X

Keywords

1 – 10 of 30