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The weather in the Arabian Gulf region constitutes an environment that is corrosive to carbon steel. In the Gulf region, atmospheric corrosion is aggravated further by the high salinity of Gulf sea‐water. In addition, sulphur dioxide and deposits from combustion products tend to make the atmosphere in the Gulf region even more corrosive. Various inhibitors are reported in the literature that can help in the prevention of metal corrosion in aqueous environments. Among these, sodium dihydrogen orthophosphate, sodium benzoate, sodium nitrite and sodium nitrate were obtained and the effectiveness of certain corrosion inhibitors on carbon steel specimens was examined in a simulated atmospheric corrosion environment containing 2% NaCl and 1% Na₂SO₄ with various inhibitor concentrations. Test specimens were prepared from locally produced carbon steel reinforcing bars. It was found as a result of the test programme that treatment of the steel with 10 or 100mM sodium dihydrogen orthophosphate for one day at room temperature resulted in the best inhibition of corrosion. The results also demonstrated that inhibitors such as sodium benzoate and sodium nitrite were only similarly effective, as was sodium nitrate. Plans further study to examine the inhibition performance of sodium dihydrogen orthophosphate under actual atmospheric conditions.

The author first discusses the factors to be considered before deciding on the use of an inhibitor. He then deals in turn with the most important inhibitors, namely sodium chromate, sodium nitrite, sodium benzoate and sodium salts of organic acids, and duplex inhibitors. He concludes with some notes on water treatment and the application of phosphates and silicates. In his first article (August), Dr. Shreir outlined the principles of inhibition.

This is the first of a series of articles surveying recent trends and new developments in specialised fields of corrosion, in this case inhibitors. A corrosion inhibitor is a substance which prevents, or reduces the rate of corrosion of a metal placed in an environment normally corrosive to it.

To investigate a new approach for making soy‐based adhesive having appropriate properties for potential application in wood industry.

Three chemicals were used for modifying protein contained in soy flour. According to orthogonal experiment design, nine soy‐based adhesives were prepared. Shearing strength of plywood bonded with these adhesives was measured to evaluate the bonding strength of nine formulas. Based on statistic analysis, the main effect factor and an optimised formula were determined. Further investigation on the modification effect to protein molecule was conducted by Fourier Transform Infrared Spectroscopy. In order to facilitate practical application, the viscosity of optimum formula adhesive was measured to determine possible working life. Three additives were added to optimise formula for reducing mould growth.

Based on soy‐flour mass, the best combination of lime milk, sodium hydroxide (NaOH) and sodium silicate was 10, 2, and 20 per cent, respectively. NaOH was considered the main effect factor on bonding strength, and sodium silicate was of the second importance. The viscosity of the optimised adhesive changed lightly in 2 h, and significantly increased from 2 to 4 h. However, it still could spread on veneer, which indicated a reasonable working life for practical application. Based on soy flour mass, when 0.5 per cent sodium benzoate or 25 per cent phenol formaldehyde was added, mould growth could be restrained after early stage.

Though the studied soy‐based adhesive had a good bonding strength and comparative water resistance, its pH was a little too high, which may cause risks of discolour of light coloured wood. Further study is needed to solve this problem.

The approach provided a bio‐adhesive with good bonding strength, comparative water resistance, reasonable working life, and without formaldehyde emission. Soy‐based adhesive is considered a promising alternate adhesive in wood industry and other applications because of the above mentioned advantages.

It provided a potential way to utilise by‐product of agriculture, soy‐flour, as industrial raw material. This will benefit farmers significantly. Meanwhile, the modified soy‐based adhesive is promising to partly or completely replace urea formaldehyde resin that are mainly used in wood industry, avoiding formaldehyde emission and reducing the dependence on petroleum products.

COPPER is by far the most important non‐ferrous metal used in industry. By virtue of its valuable physical and mechanical properties, long life, comparative cheapness and high scrap value, it occupies a position next only to iron and steel in commercial importance.

CORROSION GROUP'S BIG PROGRAMME. THE Corrosion Group's programme of meetings for 1954–55—the fourth session since the Group was formed—looks to be the most interesting planned so far. There are three outstanding events. In chronological order they are the Conversazione and Exhibition with the theme ‘Corrosion Prevention in the Home,’ to be held on January 20 at Battersea Polytechnic, London; the spring lecture, ‘Attention to Corrosion in U.S.A.,’ by the distinguished American corrosion scientist, F. L. LaQue, to be held on March 30 at Burlington House, London, W.I; and the ambitious Symposium on the Protection of Structural Steel scheduled for March 31 and April 1 in London. The conversazione is to be followed by a discussion on ‘Corrosion in the Home’ on February 16.

On March 11–12 ten informative papers on various corrosion aspects were given at the ‘Symposium on the Protection of Motor Vehicles from Corrosion’, held at the Institution of Mechanical Engineers, Birdcage Walk, London, and organised by the Society of Chemical Industry Corrosion Group. Abstracts of five of these papers are given below. Abstracts of the remaining five papers will be published in the May issue of CORROSION TECHNOLOGY.

The performance of commercial aluminium as a sacrificial anode for cathodic protection of mild steel in 0.3% sodium chloride has been studied in alkaline compositions for anolyte based on slaked lime. The influence of several addition agents has been investigated with a view to suppressing local cell action in the above‐mentioned environment.

This paper aims to identify an inhibitor to protect rebar corrosion in concrete.

The authors use the simple method of polarization and calculate the change in open-circuit potential and corrosion current density.

Sodium molybdate is an efficient inhibitor compared with sodium tungstate for rebar corrosion in concrete.

This paper has limitation of 0.0001 M concentration of inhibitors for 400 days of exposure in 3.5 per cent sodium chloride solution.

The research focused on the concentration of both inhibitors in the range from 0.1 to 0.0001 M, which resulted in greater structural protection from corrosion in adverse conditions, such as coastal areas.

The corrosion of metals can be reduced or prevented by influencing the electrode processes of electrochemical corrosion cells with suitable chemical additions to the corrosive electrolyte. It is the purpose of these articles to consider the mechanism of inhibition, and the applications and limitations of typical inhibitors. This first article is devoted to a consideration of the principles of inhibition in aqueous neutral solutions.