Reducing emissions of carbonyl compounds and regulated harmful matters from a heavy-duty diesel engine fueled with paraffinic/biodiesel blends at one low load steady-state condition

This study investigated the emissions of carbonyl compounds (CBCs) and regulated harmful matters (traditional pollutants) from an HDDE (heavy-duty diesel engine) at one low load steady-state condition, 24.5% of the max load (40 km h^?1), using five test fuels: premium diesel fuel (D100), P100 (100% palm-biodiesel), P20 (20% palm-biodiesel + 80% premium diesel fuel), PF80P20 (80% paraffinic fuel + 20% palm-biodiesel), and PF95P05 (95% paraffinic fuel + 5% palm-biodiesel). Experimental results indicate that formaldehyde was the major carbonyl in the exhaust, accounting for 70.3–75.4% of total CBC concentrations for all test fuels. Using P100 and P20 instead of D100 in the HDDE increased CBC concentrations by 9.74% and 2.89%, respectively. However, using PF80P20 and PF95P05 as alternative fuels significantly reduced CBC concentrations by 30.3% and 24.2%, respectively. Using PF95P05 instead of D100 decreased CBCs by 30.3%, PM by 11.1%, THC by 39.0%, CO by 34.0%, NOx by 24.3%, and CO₂ by 7.60%. The wide usage of paraffinic–palmbiodiesel blends as alternative fuels could protect the environment. However, it should be noted that only one engine operated at one low load steady-state condition was investigated.     

Direct assessment of international consistency of standards for ground-level ozone: strategy and implementation toward metrological traceability network in Asia

An international exercise to directly assess consistency of standards for ground-level ozone in East Asia was conducted as part of the East Asian Regional Experiment 2005 (EAREX 2005) in the framework of the Atmospheric Brown Clouds (ABC) project. Ten organizations collaboratively participated in the intercomparison. Four groups representing Japan, Korea, Hong Kong, and Taiwan made comparisons at the Gosan super observatory, Jeju Island, Korea, in March 2005, with ozone instruments calibrated to their national standards, and four Japanese groups made off-site comparisons with laboratory-level standards. All comparisons generally indicated good agreement with the standard reference photometer (SRP) 35, built by the National Institute of Standards and Technology (USA) and maintained by the National Institute for Environmental Studies (Japan). The assessment was expanded to measurement networks contributing to the World Meteorological Organization's Global Atmospheric Watch (WMO/GAW) program as part of off-site comparisons, and excellent agreement was achieved. These efforts contribute to propagating traceability of the national metrology standards among the atmospheric science community, to ensuring comparability of the existing ozone measurements, and to establishing an integrated network of air quality monitoring in Asia.     

Biomarkers responses of the earthworm Eisenia fetida to acetochlor exposure in OECD soil

To examine the potential of a suite of biomarkers as early warning indicators of environmental pollution, sperm count, neutral red retention time (NRRT) and DNA damage were measured in earthworm Eisenia fetida exposed to increasing concentrations of acetochlor in OECD soil. The neutral red retention time of earthworms coelomocytes was sensitive to acetochlor pollution, and decreased significantly when the concentration was more than 10mgkg(-1) after 30 and 60 days of exposure (P<0.05). The reduced neutral red retention time correlated with the soil acetochlor residual. Sperm count decreased significantly at the concentrations of 40 and 80mgkg(-1) after 15 days of exposure (P<0.05). The DNA damage of earthworms coelomocytes increased significantly after 30 days of exposure at the highest concentration (80mgkg(-1); P<0.05). Earthworms were under physiological stress at field dose of acetochlor (10mgkg(-1)). Higher concentrations of acetochlor caused sperm count decrease and DNA damage of earthworms. Such a suite of biomarkers could serve as indicators of the health of the soil environment and to evaluate the toxicity of acetochlor on earthworms or as a means of monitoring soil acetochlor pollution.