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The purpose of this paper is to evaluate the effect of antioxidant 2,6-di-tert-butyl-p-methylphenol (BHT) on the thermal stability and fatigue resistance of spirooxazine and then study the properties of photochromic polyvinyl butyral resin (PVB) films.

BHT was introduced into the spirooxazine system by blending and covalent bonding. The properties of spirooxazine solutions and photochromic PVB films were studied.

The thermal stability and fatigue resistance of spirooxazine covalently linked (BHT-SO) or mixed (BHT/SO) with BHT were higher than the system without BHT, and BHT-SO was the better one. But acidic substance would greatly impair the fatigue resistance of spirooxazine. The optimum addition amount of BHT-SO2 to PVB was 2.5 per cent, and the minimum limit was 0.01 per cent. The fading kinetic and fatigue resistance of film were similar to the solution and better. Plasticizer could accelerate the fading rate and strengthen the mechanical properties of photochromic film but had no effect on the fatigue resistance.

Spirooxazine could be grafted onto the PVB chain to make the ring closure fading reaction slower.

In addition to the wide application prospects of photochromic materials in decoration, optical storage, etc., the photochromic PVB film in the car safety glass can absorb sunlight and turn blue, then fade to colorless when the sunlight disappears, making the interior environment more comfortable.

The introduction of BHT into the spirooxazine system not only exerts its ability to capture free radicals, but its bulky volume also increases the resistance of the ring closure, making the fading process slower.

In this study, research was concerned primarily with the development of test methods that are sufficiently sensitive to detect the initial degradation of selected exterior coatings exposed to various pollutant‐containing environments. The test methods employed in generating dose response data included erosion rates, attenuated total reflectance (ATR), gloss and sheen, surface roughness, tensile strength and scanning election microscopy. Five commercially important paint systems were selected for characterizations including an oil house paint, latex coating, an alkyd industrial maintenance coating, a coil coating and an automotive refinish lacquer. The properties of the coating systems were determined periodically consequent to ‘short term’ exposure at four exterior locations and to various pollutant‐containing environments under controlled, but accelerated conditions in an Atlas Xenon Arc Weather‐Ometer® Model 600WR12. The test sites for the former ‘short term’ exterior study were located at Leeds (north central), North Dakota; Los Angeles, California; Chicago (Research Center), Illinois and Valparaiso, Indiana. These sites represent a ‘clean’ rural environment, a high O3 environment, a high SO2 environment, and a relatively high O3 environment plus a moderate SO2 environment, respectively. In the accelerated laboratory exposure study, five enenvironmental pollutant conditions were employed in the Weather‐Ometer including a zero pollutant, 0·1ppm and 1·0ppm SO2 and 0·1ppm or 1·0ppm O3 level. The zero pollutant condition represents the control (clean air) with 0·1 ppm of each pollutant type considered representative of the levels frequently reached in polluted cities. The 1·0ppm levels represent a highly polluted (industrial) site.

For many years the effect of sulphuric anhydride in the atmosphere has been recognised, such as in the report by Thomson. As an example of this, consider some of the work reported by Hudson and Stanners, who exposed iron and steel to copper in a variety of environments. When they studied the results, they found a close relationship between the degree of corrosion and the amount of SO2 present, whereas the effect of chlorides was restricted to a narrow test area close to the sea.

This study develops the economic rationale for the inclusion of new environmental financial assets, tradable pollution rights, in a well‐diversified portfolio. These new assets are generated and their valuation determined in the market‐incentive environmental regulatory approach called emissions trading, especially the cap‐and‐trade variant. This approach has been gaining wide acceptance and approval. A leading example is the sulfur dioxide market where tradable allowances are assets that may be held by private investors. Transactions in this market have reached volumes indicative of a high degree of liquidity. Comparable tradable rights in other pollutants are under active development. We explain the design and workings of these markets and demonstrate empirically, on the basis of time series data, that sulfur dioxide allowances have rates of return and yield distributions that make them candidates for inclusion in asset portfolios. We conjecture that other tradable pollution rights will exhibit similar properties when sufficient data are available. Financial analysts and accountants are likely to play an increasing role in advising investors about the role of these assets in a well‐diversified portfolio.

The emission of SO2, a dangerous atmospheric pollutant, is the major problem with increasing the use of coal as fuel in various industries, particularly in thermal power plants. A variety of methods for minimizing the SO2 emission have been reported in the literature, among which the desulphurization of the flue gas, generated by combustion of coal receives much attention and is termed as flue gas desulphurization (FGD). FGD scrubbers have found widespread use in thermal power plants, smelters, incinerators and various refining operations. The scrubber parts must resist corrosion from solution which have a varying degree of acidity and erosion, besides containing substantial concentrations of chlorides and SO2, and the unfavourable conditions of fluctuations in temperature. The currently‐used type 316L stainless steel material in many FGD installations, were reported to have failed, due to the localized corrosion attack by the aggressiveness of the environment encountered during scrubbing of SO2. Normally, the improvement in corrosion performance of the construction materials can be achieved by:

Ports create harmful effects on their adjacent population because ships discharge noxious gases like SO_X, NO_X, and particulate matter (PM). To tackle this problem, some ports started to control emission through regulations such as Emission Control Areas (ECA) and Reduced Speed Zone (RSZ). This paper estimates the social cost of ship emission and eco-efficiency at the Port of Incheon (POI). We further examine how the ECA and RSZ designation can reduce the social cost. The estimation is based on the activity-based approach, where ship type, engine, and movement are used to measure fuel consumption and then emission. Results suggest that the social cost of ship emission at the POI amounts to $90,805,478. The eco-efficiency of the POI, compared to the one at the Port of Las Palmas in another study, is substantially better. Under RSZ, the corresponding emission abatement values are $4,485,308, $2,642,009 and $21,932,435 from SO₂, NO_X and PM reduction, respectively. If 1.0% and 0.1% sulfur fuel are used complying with rules of the ECA, the social cost savings amount to $8,174,947 and $12,868,842 from SO₂ reduction.

The influence of corrosive gases on the solderability of palladium/silver thick‐film conductors has been investigated. An experimental set‐up for atmospheric corrosion testing has been constructed in which atmospheres can be created comparable to a heavily polluted industrial environment. Various Pd/Ag thick‐film conductors have been submitted for 14 days to flowing atmospheres containing 1 ppm SO2, 15, 0·2 or 0·04 ppm H2S, 1 ppm NO2, 1 ppm O3 and 0·05 ppm Cl2, separately or in various combinations. When used separately, only H2S causes a poor solderability of the thick‐film conductors. This effect on the solderability turns out to be independent of the H2S concentration; even concentrations as low as 0·04 ppm cause identical corrosion phenomena. The other gases mixed with H2S have a synergistic effect on the corrosion process.

Objective – This chapter examines the performance of the market to discover efficient equilibrium under alternative auction designs.

Background – Auctions are increasingly being used to allocate emissions allowances (“permits”) for cap and trade and common-pool resource management programs. These auctions create thick markets that can provide important information about changes in current market conditions.

Methodology – This chapter uses experimental methods to examine the extent to which the predicted increase in the Walrasian price due to a shift in willingness to pay (perhaps due to a shift in costs of pollution abatement) is reflected in observed sales prices under alternative auction formats.

Results – Price tracking is comparably good for uniform-price sealed-bid auctions and for multi-round clock auctions, with or without end-of-round information about excess demand. More price inertia is observed for “pay as bid” (discriminatory) auctions, especially for a continuous discriminatory format in which bids could be changed at will, in part because “sniping” in the final moments blocked the full effect of the demand shock.

Conclusion – Uniform-price auctions (clock and sealed-bid uniform-price, and continuous uniform-price) generate changes in purchase prices that are reasonably close to predicted changes. There is some evidence of tacit collusion causing prices to be too low relative to predictions in most cases. The worst price tracking was observed for discriminatory auctions.

Application – Uniform-price auctions appear to perform at least as well as other auction designs with respect to discovery of efficient market prices when there are unexpected and unannounced changes in willingness to pay for permits.

TESTING ELECTRO‐DEPOSITED COATINGS. The necessity for accurate correlation between laboratory testing and actual service trials of electro‐deposited coatings to determine their corrosion‐resistant properties was the theme of the meeting held at the headquarters of the Society of Chemical Industry on October 21 last. The meeting was a joint meeting of the Corrosion Group of the Society with the London Section of the Institute of Metal Finishing, under the chairmanship of Dr. S. G. Clarke. The two speakers were Dr. J. Edwards of the British Non‐Ferrous Metals Research Association and J. H. Hooper of Humber Ltd.

The reactions between a food additive and the components of the food to which it is added are not restricted to the preservative action. Dr B.L. Wedzicha describes the chemical consequences of the use of sulphur dioxide as a food additive.