نمایش همه 3 نتیجه
Dry reforming of CH4 over solid solutions of LaNi1xCoxO3
LaNi1xCoxO3 perovskite-type oxides were synthesized by the sol–gel resin method and used as catalysts precursors in the dry reforming of methane to syngas between 600 and 800 8C at atmospheric pressure, the reaction was studied under continuous flow using an mixture of CH4:CO2 = 1:1. The solids were characterized by X-ray diffraction (XRD), BET specific surface area and temperature-programmed reduction (TPR). XRD analysis of the solids shows LaNiO3 and/or LaCoO3 as the main phases present on the solids depending on the degree of substitution. The more intense peaks and cell parameters showed formation of Ni-Co solid solutions. The as-synthesized solids were reduce during catalytic tests to form Ni0, Co0 and La2O2CO3 as the active phases which remain during the reaction and are responsible for the high activity shown by the solids inhibiting carbon formation, with CH4 and CO2 equilibrium conversions near 100%, except for LaCoO3 that showed a poor activity.
GUIDELINES FOR CONSUMPTION OF FISH AND SHELLFISH FROM CLEAR LAKE, CACHE CREEK, AND BEAR CREEK (LAKE, YOLO, AND COLUSA COUNTIES)
The Office of Enviroرایگان!
The Office of Environmental Health Hazard Assessment (OEHHA), formerly part of the Department of Health Services (DHS) but now in the California Environmental Protection Agency, issued a health advisory in 1987 for sport fish from Clear Lake (Lake County) based on mercury contamination in edible fish tissue collected from the lake (Appendix I). Since the advisory was issued, additional data have been collected for Clear Lake fishes as well as for fish from surrounding water bodies, including Cache Creek and Bear Creek. The Central Valley Regional Water Quality Control Board (CVRWQCB) compiled a large dataset comprised of historical and more recently collected fish tissue data principally for Clear Lake but including data from the nearby water bodies. The CVRWQCB used this dataset to develop a Total Daily Maximum Load (TMDL) for mercury for Clear Lake to lower mercury levels in the watershed such that human and wildlife health are protected (Cooke, 2002). This dataset was reviewed by OEHHA, and data suitable for issuing fish consumption advisories were selected and used to update the advisory for Clear Lake and to determine whether there may bepotential adverse health effects associated with consuming sport fish from Cache Creek and Bear Creek.
Health Advisory for Fish and Shellfish from Clear Lake, Cache Creek, and Bear Creek (Lake, Yolo, and Colusa Counties)
Why has OEHHA develoرایگان!
Why has OEHHA developed a new health advisory for fish from the Clear Lake and Cache Creek watersheds ?A fish consumption advisory was issued for Clear Lake in 1987. Since that time, many more samples of fish have been collected as part of studies on mercury contamination in the Clear Lake and Cache Creek atersheds. The Office of Environmental Health Hazard Assessment (OEHHA) used the information from these studies to update the advisory for Clear Lake and develop new consumption guidelines that reflect current scientific information on mercury. Also, fish were tested for mercury from nearby Cache Creek and Bear Creek. OEHHA used these results to develop guidelines for sport fish consumption from these water bodies as well. One set of guidelines applies to women of childbearing age and children age 17 years and younger, who are particularly sensitive to methylmercury (the most prevalent form of mercury in fish). A second set applies to women beyond their childbearing years and men.