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This paper aims to report a novel preparation method of titanium dioxide (TiO₂)/zinc oxide (ZnO) composites with different mole ratios of TiO₂:ZnO and their photocatalytic activity.

TiO₂/ZnO composites are prepared by a facile route. X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM) and ultra-violet–visible diffuse reflectance spectra (UV-vis DRS) are used to characterize the products. Photocatalytic activity of the samples is evaluated by degradation of persistent organic pollutant pentachlorophenol under ultra-violet (UV) irradiation.

It is found that all the as-prepared TiO₂/ZnO composites not only have good catalytic activity under UV light irradiation, but also have excellent circulation stability. The optimal mole ratio of TiO₂:ZnO is 0.75:1.

This report presents a simple and rapid method for the preparation of TiO₂/ZnO composites with excellent photocatalytic activity. Experimental results could provide useful reference for the treatment of chlorophenols in the future.

AT the request of the Crown Agents for the Colonies investigations were made into the possibility of improving the Standard Specification No. 40 (revised February 1937) on methods for protecting the bindings of books from attacks by insects and fungi.

This paper aims to report a novel preparation method of ZnO particles with different structures and their photocatalytic activity.

ZnO powders are prepared by a facile, economical and environment-friendly aqueous solution route. X-ray diffraction, field emission scanning electron microscopy, energy dispersive spectroscopy, transmission electron microscopy and UV-vis diffuse reflectance spectra are used to characterize the products. Photocatalytic activity of the samples is evaluated by degradation of organic pollutant pentachlorophenol under UV-vis irradiation.

It is found that three-dimensional ZnO hierarchical structures can be prepared via aqueous solution route without using any template or structure-directing agent, and the alkalinity of reaction solution is the key factor. All the as-prepared ZnO products have good catalytic activity under UV-vis light irradiation.

This report presents a simple method for the preparation of ZnO particles with excellent photocatalytic activity. Experimental results could provide useful reference for the treatment of chlorophenols in the future.

An abridged version of the final report by the Paint Research Association on Department of the Environ‐ment Contract CR10184

Nowadays trace organic pollutants represent a major concern in water treatment systems. Activated carbon has been used for most applications aiming at the reduction of these kind of compounds in aqueous effluents, but regeneration needs and high operation costs led to a renewed interest in the search for alternative sorbents. Pine bark is an excedentary raw material from sawmills in Portugal, and therefore a profitable natural resource that has already been successfully tested in the adsorption of organochlorines from contaminated water. This study aims at characterizing the pine bark surface structurally and chemically, to understand the nature of sorption occurring when a trace organic contaminant is present in aqueous effluents. Pentachlorophenol (PCP) was the trace contaminant used in the experiments. Scanning electron microscopy (SEM), mercury porosimetry, Fourier transform infrared spectroscopy (FTIR) and X‐ray photoelectron spectroscopy (XPS) were the techniques used, in addition to classical chemical analysis and solid phase micro extraction (SPME) prior to gas chromatography with mass spectrometry (GC‐MS) for PCP quantification. The pine bark proved to be a material of very low porosity, low specific surface area, strong carbon aromatic content probably relative to polyphenols and lignin composition. Sorption experiments showed a good correlation for the linear adsorption isotherm, as well as the desorption experiments. In the conditions tested, the average PCP removal after 24 h was above 98 per cent. This material proved to be an encouraging sorbent for cheap water remediation solutions.

The milling properties of polybutadienes have been improved and scorch time decreased by the use of aluminium naphthenate, which can also be employed to ensure homogenous distribution of pigments in polyesters. Aluminium secbutoxide/naphthenic acid reaction products are useable in the preparation of cellular polyurethanes and mixtures of the material with polyethylene have been applied to textile fabrics. The naphthenate possesses rubber‐like properties to a certain extent and was in fact used as a rubber extender during the First World War. Mixtures of naphthenates and pentachlorophenol compounds have been utilised to preserve wood. Alum naphthenate has been used to produce poly (naphthenaluminophenyl siloxanes), polymers containing radicals f naphthenic acid chemically bound with aluminium atoms in the side chains. The product contains 9% silicon, 4.52% aluminium, approximate molecular weight 1600, and are easily soluble in benzene, toluol, carbon tert, and ether, giving stable film‐forming transparent solutions, whose films have an electrical volume resistency of 3.1 x 1015 ohms‐cm, a tongent of dielectric loss angle of 0.0082, an electric strength of 68.3 kv/mm and a dielectric constant of 2.9. Although the mechanical strength of these films is not high it can be increased by heating 10 hours at 120°C. When added to other silicon‐organic or organic polymers these products accelerate their drying gelatinization and hardening.

Seven years arduous service from fibre glass pump. A Fybroc fibre glass horizontal end suction centrifugal pump, supplied by Alpha Technical Services Limited, has given more than seven years service on a difficult duty at speciality chemicals manufacturers Catomance Limited, Welwyn Garden City. The pump handles an Ester, Pentachlorophenol Laurate, together with acidic water and other corrosive and abrasive by products.

Purpose – This chapter explores the policy formation process for chemical pollution in the An-Shun Plant case. Two major policies including the closing policy and the 1.3 billion NT dollars’ compensation were studied.

Design/methodology/approach – This chapter first analyzes the background of the An-Shun Plant case, the closing policy, and the compensation policy. Analytically, a comparison of the closing policy and compensation policy are offered using Kingdon's (1984) theories of policy formation.

Findings – It was found that both inside and outside government factors were important from the analysis of the two formed policies. For the closing policy, inside government factors were more important than outside government factors. On the contrary, outside government factors were more important for the compensation policy.

Originality/value of the chapter – Environmental policies, especially compensation policy processes, were often ignored. This chapter signifies the importance of environmental policy formation.

Past and current uses of chemical treatments to control or eradicate fungal infections and/or insect infestations in buildings have led to a number of reported cases where occupants and users of these buildings have suffered various physical symptoms. The role of chemical treatments, whether as biocides, fungicides, insecticides or wood preservatives, has therefore come under scrutiny and various countries are now reviewing their use in favour of a more benign approach to the management of decay in buildings. Growing concern for the environment and the health of those treating or living in treated buildings has also led to changes in the way we perceive and deal with buildings and building defects. As a result, the conventional approach to survey, defect diagnosis and remediation has to be re‐thought and placed in the context of a wider environmental agenda. This paper provides evidence for how historic chemical treatments can have effects on the health of the building and its occupants, and considers the implications of such treatments for those charged with specifying or undertaking works to the fabric of affected buildings.

Preparation of new organotin polymers via a new synthetic route based on the exchange reactions of pentachlorophenyl acrylate or methacrylate with amino‐tri‐phenyltin benzoates or hydroxyl‐tri‐phenyltin benzoates.

The pentachlorophenyl acrylate or methacrylate was prepared by polymerisation in solution with azobisisobutyrontrile as a free radical initiator. The polymers obtained were allowed to undergo exchange reactions with amino‐tri‐phenyltin benzoates or hydroxyl‐tri‐phenyltin benzoates. The structure of the polymers prepared was confirmed by IR spectroscopy. Films were prepared from purified organotin polymers solution on glass, PVC and tin plates. The release of tin compound from the films, when immersed in aqueous media, was assessed. The concentration of the released tin (ppm) was measured by atomic adsorption spectrophotometer.

The new synthetic route was effective, the organotin polymers prepared had good film properties and the release of tin compounds increased with the content of tin in the organotin polymers.

The alkaline resistance of the polymeric films prepared needs improvement.

The polymers prepared provide a family of effective polymeric fungicide useful for a number of applications including water sterilisation.

The polymers prepared contained pendent triphenyltin moieties which slowly hydrolysed to give fungicidal and antifouling effects.