EXPERIMENTAL STUDY ON ASCORBIC ACID ADDITIVE AS GREEN INHIBITOR AGAINST CORROSION OF MILD STEEL

Purpose of study: The corrosion behavior of mild steel and the inhibition effect of ascorbic acid (an anti-oxidant additive) on aluminum coatings on the mild steel have been studied by weight loss technique under different corrosive medium. Methodology: Tap water, 3% Na2CO3 solution, seawater and open-air were chosen as different corrosive medium at ambient temperature range of 35- 400C. Corrosion was recorded using the weight-loss method and the rate was calculated. Later similar mid steel samples were coated with Sodium Bicarbonate paste, aluminum paint with ascorbic acid additive, and aluminum paint without ascorbic acid additive, in similar corroding medium, and the corrosion rate was calculated using the weight-loss method. Main Findings: Results show that the percentage of mild steel corrosion was found to be highest in the seawater and lowest in 3% Na2CO3 solution. Sodium Bicarbonate paste reduces the corrosion rate more studies on the corrosion protection was performed by coating the mild steel surface with aluminum paint along with ascorbic acid inhibitor i.e., a green corrosion inhibitor and it was found that the weight loss data is: 85.03 g from 85.05 g, 82.39 g from 82.43 g, no weight loss and 85.73 g from 85.74 g in tap water, seawater, 3% Na2CO3 solution and air medium respectively. Thus, the addition of ascorbic acid inhibitor gave the highest inhibition efficiency for aluminum paint.

Progress on Environmentally Compliant Aluminum Ceramic Compressor Coatings

During the last decade there has been an increasing emphasis on compliance to ever stricter environmental laws as well as compliance to regulations that have been designed to protect workers from exposure to toxic or otherwise harmful substances or processes. This world-wide emphasis has forced a continuing review of materials and processes used in the manufacture and protection of compressor materials from corrosion. Turbine compressors have been coated with silicone aluminum paint, diffused nickel cadmium and aluminum pigmented ceramic coatings that contain hexavalent chromium. These three processes utilize various chemicals including toxic substances, carcinogens and volatile organic compounds (VOC). All three of the coating processes need to be either made compliant or eliminated from use. This paper will review efforts that have been made to develop compliant aluminum ceramic compressor coating materials as applied to various steel and stainless steel substrates. In all cases the new materials that have been developed are free of toxic or carcinogenic materials. Test results will be compared to specification requirements for chrome containing compressor coatings in the area of physical properties including surface finish, thickness and adhesion. Additionally, environmental test data will be presented based on standard test methods that compare new compliant coatings with conventional chrome containing materials. Finally, process steps and conditions will be described for these new coatings.

Influence of Mulches on the Colonization by Adults and Survival of Larvae of the Colorado Potato Beetle (Coleoptera: Chrysomelidae) in Eggplant

Six treatments (no mulch, black plastic mulch, black plastic painted with reflective aluminum paint, straw mulch, black plastic plus straw, and a living mulch of rye growing between the rows) were used to grow eggplant and to observe the effects on movement of adult Colorado potato beetles, Leptinotarsa decemlineata (Say); oviposition; and density and survival of larvae. Straw mulch and rye treatments reduced movement of overwintered beetles into the plots and also reduced the growth of the plants compared to black plastic mulch. Survival from the egg to small larva (first and second instar) was lower in the plots with straw mulch and black plastic plus straw than in plots with rye, bare ground or aluminum-painted mulch. None of the treatments had an effect on movement of the first generation adults, which was primarily determined by the proximity of the plots to the source field of potatoes. It may be possible to combine the positive effects of black plastic on early season growth and straw mulch on reducing the survival of potato beetle larvae by transplanting the eggplants into black plastic mulch, then adding straw as the egg masses of the potato beetle begin to hatch.