These data suggest that, under these solvent use scenarios, petroleum-based solvent products produced in the United States after 1978 likely did not produce airborne benzene concentrations above those measured if the concentration was less than 0.1% benzene.
The studied solvent products containing 0.07% benzene (spiked) did not exceed the current OSHA permissible exposure limit of 1 ppm (averaged over 8 h) or the ACGIH Threshold Limit Value of 0.5 ppm, in any of the tested short-term exposure scenarios.
However industrially formulated solvent products are often combined with basic additives such as alkylamines to improve their performance; and the mineral surfaces of aquifer rocks and sediments usually possess a range of acid and hydrogen-bonding adsorption sites.
Therefore, in order to relieve PM2.5 pollution, control strategies for OC and NH+4 would be enhanced by government through improving the quality of oils and solvent products, decreasing the amount of nitrogenous fertilizer utilization, or changing the fertilizing environment from dry condition to wet condition.
These constraints artificially specified ranges for secretion rates of acid and solvent products.
The anaerobic ethanol yield at 13 h was 0.497 g/g of glucose or 97% theoretical and less than 1% of the yield went to solvent products other than ethanol or CO2 (Fig. 1).
However, as is the case in many mesophiles, TGPAs are generally sensitive to excessive concentrations of their own solvent products [ 27], which reduce cell vitality, impair membrane integrity, inhibit enzymes and/or perturb intracellular pH balance [ 29, 30].
The trials enabled to select the application solvent, the product concentration and the application conditions that gave the best results.
Moreover, because CO2 is a gas at ambient conditions, removal of the solvent from product is facilitated [18].
