Internal circulating fluidized bed incineration system and design algorithm

ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅｐｒｏｃｅｓｓｏｆｍｕｎｉｃｉｐａｌｓｏｌｉｄｗａｓｔｅ(ＭＳＷ)ｉｓｏｎｅｏｆｔｈｅｍｏｓｔｓｅｒｉｏｕｓｉｓｓｕｅｓｉｎｔｅｒｍｓｏｆｅｎｖｉｒｏｎｍｅｎｔａｌｐｒｏｔｅｃｔｉｏｎ.ＰｒｏｃｅｓｓｉｎｇｏｆＭＳＷｗｉｔｈｏｕｔｆｕｒｔｈｅｒｄｉｓａｓｔｒｏｕｓｃｏｎｔａｍｉｎａｔｉｏｎｃａｎｂｅａｃｈｉｅｖｅｄｏｎｌｙｉｎｍｏｄｅｒｎｉｚｅｄｍｅａｓｕｒｅｓ,ｓｕｃｈａｓｉｎｃｉｎｅｒａｔｉｎｇａｎｄｅｎｅｒｇｙｇｅｎｅｒａｔｉｎｇｃｏｎｃｕｒｒｅｎｔｌｙ(Ｓｈｅｎ…     

Chinese life cycle impact assessment factors

ＩｎｔｒｏｄｕｃｔｉｏｎＬｉｆｅｃｙｃｌｅａｓｓｅｓｓｍｅｎｔ(ＬＣＡ)ｉｓａｎｅｎｖｉｒｏｎｍｅｎｔａｌｍａｎａｇｅｍｅｎｔｔｏｏｌｔｈａｔｉｓｕｓｅｄｔｏｅｘａｍｉｎｅａｎｄｅｖａｌｕａｔｅｔｈｅｅｎｖｉｒｏｎｍｅｎｔａｌｉｍｐａｃｔｓａｓｓｏｃｉａｔｅｄｗｉｔｈｔｈｅｅｘｉｓｔｅｎｃｅｏｆｐｒｏｄｕｃｔｓ(Ｊｅｎｓｅｎ,1998;Ｗｅｉｄｅｍａ,1997;Ｗｅｎｚｅｌ,1997).ＴｈｅｆｏｃｕｓｏｆＬＣＡｉｓｏｎｔｈｅｅｎｔｉｒｅｌｉｆｅｃｙｃｌｅｏｆｔｈｅｐｒｏｄｕｃｔ,ｉ.ｅ.ｆｒｏｍｔｈｅｅｘｔｒａｃｔｉ…     

Soil and water characteristics of a young surface mine wetland

Coal companies are reluctant to include wetland development in reclamation plans partly due to a lack of information on the resulting characteristics of such sites. It is easier for coal companies to recreate terrestrial habitats than to attempt experimental methods and possibly face significant regulatory disapproval. Therefore, we studied a young (10 years) wetland on a reclaimed surface coal mine in southern Illinois so as to ascertain soil and water characteristics such that the site might serve as a model for wetland development on surface mines. Water pH was not measured because of equipment problems, but evidence (plant life, fish, herpetofauna) suggests suitable pH levels. Other water parameters (conductivity, salinity, alkalinity, chloride, copper, total hardness, iron, manganese, nitrate, nitrite, phosphate, and sulfate) were measured, and only copper was seen in potentially high concentrations (but with no obvious toxic effects). Soil variables measured included pH, nitrate, nitrite, ammonia, potassium, calcium, magnesium, manganese, aluminum, iron, sulfate, chloride, and percent organic matter. Soils were slightly alkaline and most parameters fell within levels reported for other studies on both natural and manmade wetlands. Aluminum was high, but this might be indicative more of large amounts complexed with soils and therefore unavailable, than amounts actually accessible to plants. Organic matter was moderate, somewhat surprising given the age of the system.     

Nitrate-reductase activity and in vivo nitrate-reduction rate in Ulva rigida illuminated by blue light

In the marine green alga Ulva rigida C. Agardh, nitrate reductase (NR) is synergetically induced by blue light and nitrate. The present study examines the effect of blue light and a large NO ₃ ^– pulse (0.3 mM) on relevant variables of NO ₃ ^– -assimilation such as NO ₃ ^– -uptake, intracellular NO ₃ ^– -storage, NR activity, in vivo NO ₃ ^– -reduction rate and NO ₂ ^– and NH ₄ ⁺ -accumulation. Nitrate uptake started immediately upon addition of NO ₃ ^– , suggesting the presence of a constitutive carrier, however in the first 1.5 to 2 h, periods of net NO ₃ ^– efflux were frequent. After this time, NO ₃ ^– -uptake and intracellular NO ₃ ^– -accumulation proceeded linearly with time, suggesting the existence of a different NO ₃ ^– -uptake mechanism, which seems to be inducible. Our results indicate that in vivo NO ₃ ^– -reduction is not exclusively dependent on the potential NR activity. In U. rigida, during the first 2 h after a NO ₃ ^– pulse (300 M) there were clear indications that the induction state of the NO ₃ ^– -carrier limits the reduction rate of NO ₃ ^– . Once the induction of the NO ₃ ^– -transporter had been completed (1.5 to 2 h), the NO ₃ ^– -assimilation pathway reached a steady state, NO ₃ ^– -uptake rate, NO ₃ ^– -reduction rate and NO ₂ ^– and NH ₄ ⁺ -accumulation being linear with time. Since the reduction of NO ₃ ^– leads mainly to the accumulation of NH ₄ ⁺ , we conclude that, after the NO ₃ ^– -reduction itself, NH ₄ ⁺ -fixation into carbon skeletons is the limiting step in the assimilation of NO ₃ ^– by U. rigida under blue light.     

UV induces reactive oxygen species,damages sperm,and impairs fertilisation in the sea urchin <Emphasis Type="Italic">Anthocidaris crassispina</Emphasis>

We demonstrated that environmentally relevant levels of UVA and UVB can reduce sperm motility (UVA: by 38–58%; UVB: by 42–85%; P < 0.05) and subsequently fertilisation success (UVA: by 38–72%; UVB: by 91–98%; P < 0.05) of urchins (Anthocidaris crassispina) in a dose-dependent manner, implicating that recruitment of urchin populations might be reduced by UVR (ultraviolet radiation) prevailing in their natural habitats. Concomitantly, reactive oxygen species (ROS) production was enhanced by UVA and UVB in a dose-dependent manner (UVA: by 1.3-fold; UVB: by 6.6–7.3-fold; P < 0.05), and the increase in ROS resulted in an increase in lipid peroxidation (LPO) in urchin sperm (UVA: by 4.2–7.2-fold; UVB: by 2.3–2.7-fold; P < 0.05). This study demonstrated that ROS production and oxidative damages enhanced by UVR may account for the observed declines in sperm motility and fertilisation, and suggests that levels of UVR prevailing in the environment may pose a significant threat to the reproductive success of natural populations of urchins spawning in shallow waters.     

Effects of pre-exposure to ultraviolet-B radiation on responses of tomato (Lycopersicon esculentum cv. New Yorker) to ozone in ambient and elevated carbon dioxide

Patterns of environmental change in the biosphere include concurrent and sequential combinations of increasing ultraviolet (UV-B) and ozone (O(3)) at increasing carbon dioxide (CO(2)) levels; long-term changes are resulting mainly from stratospheric O(3) depletion, greater tropospheric O(3) photochemical synthesis, and increasing CO(2) emissions. Effects of selected combinations were evaluated in tomato (Lycopersicon esculentum cv. New Yorker) seedlings using sequential exposures to enhanced UV-B radiation and O(3) in differential CO(2) concentrations. Ambient (7.2 kJ m(-2 )day(-1)) or enhanced (13.1 kJ m(-2) day(-1)) UV-B fluences and ambient (380 microl l(-1)) or elevated (600 microl l(-1)) CO(2) were imposed for 19 days before exposure to 3-day simulated O(3) episodes with peak concentrations of 0.00, 0.08, 0.16 or 0.24 microl l(-1) O(3) in ambient or elevated CO(2). CO(2) enrichment increased dry mass, leaf area, specific leaf weight, chlorophyll concentration and UV-absorbing compounds per unit leaf area. Exposure to enhanced UV-B increased leaf chlorophyll and UV-absorbing compounds but decreased leaf area and root/shoot ratio. O(3) exposure generally inhibited growth and leaf photosynthesis and did not affect UV-absorbing compounds. The highest dose of O(3) eliminated the stimulating effect of CO(2) enrichment after ambient UV-B pre-exposure on leaf photosynthesis. Pre-exposure to enhanced UV-B mitigated O(3) damage to leaf photosynthesis at elevated CO(2).     

Heavy metal geochemistry of saltmarsh soils from the Ría of Ortigueira (mafic and ultramafic areas, NW Iberian Peninsula)

Concentrations of Fe, Mn, Ni, Cu, Cr and Zn in their total, silicate, organic, reactive and pyrite fractions were determined in soils collected from the Ortigueira saltmarshes (Esteiro, Ladrido and Mera, NW Iberian Peninsula), from sediments of the Landoi and Esteiro Rivers, and from sludge generated by a nearby dunite mine. The Esteiro saltmarsh presented clear enrichments of the four metals studied (first 10 cm), especially of Ni and Cr, whose concentrations were among the highest. It is proposed that the elevated Cr and Ni levels found in the Esteiro saltmarsh were derived from recent contributions of the mine, which are partially discharged into the Landoi River. Total Cu and Zn concentrations were lower than the corresponding ones for Cr and Ni. Under suboxic conditions, Ni, Cr, Cu and Zn were mainly associated with the reactive fraction. Under anoxic conditions, Cu and Ni were associated mainly with the pyrite phase. Pyritic Zn and Cr concentrations were relatively low and similar in all three saltmarshes; however, where anoxic-sulfidic conditions prevailed these two metals were mainly associated with the reactive and organic fractions.