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1.
《Journal of Agricultural and Environmental Ethics》2004,17(1):103-109
Instructions for Authors
Instructions for Authors 相似文献2.
《Journal of Agricultural and Environmental Ethics》2002,15(1):143-149
Instructions for Authors
Instructions for Authors 相似文献3.
News And Comments
Support for Hawaiian humpback whales 相似文献4.
W. J. Granville Beynon 《The Environmentalist》1989,9(4):299-299
News And Comments
World data centre for greenhouse gases 相似文献5.
The performance of polyurethane rotating discs (RBC-1) versus polystyrene rotating discs (RBC-2) for the treatment of an up-flow anaerobic sludge blanket (UASB) reactor effluent fed with domestic wastewater was investigated. Both RBC units were operated at the same organic loading rate (OLR) of 10.5 gCOD/m2 d. and a hydraulic retention time (HRT) of 2.5 h. The residual values of COD fractions (CODsuspended, CODcolloidal and CODsoluble) in the treated effluent of RBC-1 and RBC-2 were similar. However, the removal efficiency of ammonia in the RBC-1 (87 ± 4%) was significantly higher than that found for RBC-2 i.e. 24 ± 6%. Moreover, RBC-1 achieved a substantial removal efficiency of 99.0 ± 1% for Escherichia coli (E. coli), while RBC-2 removed 91.2 ± 0.3%. Based on these results, optimization of RBC-1 treating UASB reactor effluent was extensively performed. The RBC-1 was operated at an OLR's of 4.0, 11 and 23 gCOD/m2 d. The results obtained showed that increasing the OLR from 11.0 to 23.0 gCOD/m2 d and decreasing the HRT from 2.5 to 1.25 h significantly declined the effluent quality of CODtotal and ammonia. However, the residual values of CODtotal and ammonia remained unaffected when increasing the OLR from 4.0 to 11.0 gCOD/m2 d and by decreasing the HRT from 5 to 2.5 h. Bacteriological examination showed that the mean residual count of E. coli remained at a level of 104/100 ml, in the effluent of RBC-1 independent on the imposed HRT. Accordingly, it is recommended to operate RBC-1 for treatment of anaerobically pre-treated sewage at an OLR of 11 gCOD/m2 d and an HRT of 2.5 h.A feed-less (ammonia limitation) period of 9.0 days followed by 9.0 days feeding with high OLR of 26 gCOD/m2 d. (raw sewage) was investigated to elaborate, if the nitrifiers of the RBC-1 are capable to convert ammonia to nitrate after totally 18 days when retuning back to the normal operating conditions. The results of the experiment clearly show a strong and immediate detrimental effect of imposing high OLR of 26 gCOD/m2 d on the nitrification process in the nitrifying RBC unit. However, after returning back to the original OLR of 10.6 gCOD/m2 d, the nitrification efficiency in the RBC unit was recovered within 2–3 days. 相似文献
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Variation in drying material and their biological differences, coupled with heat supply method in different dryers, makes mathematical modeling of drying complicated. Attempt was made to simulate a drying process and to identify best suitable model out of six selected drying models, for drying of ginger slices in a solar-biomass integrated drying system designed and developed for spice drying. Moisture content data were converted into the moisture ratio (MR) expressions and curve fitting with drying time for the selected drying models was analyzed. Sigma Plot software was used for nonlinear regression to the data obtained during drying and for modeling of drying curves. The suitability of the models was evaluated in terms of statistical parameters such as coefficient of determination (R2), mean percentage error (P), and standard error estimate. Drying air temperature was in the range of 47–55°C and air velocity was between 1.0 and 1.3 m s?1. Ginger slices were dried from 88.13% to 7.65 ± 0.65% (wb) in 16 h. Trays were interchanged in a predetermined matrix sequence from 4 h onwards when moisture content was reduced to 60–70% (wb), for uniformity in drying. Highest value of R2 (0.997), lowest value of SEE (0.020), and P value < 0.0001 established Page model as the best suitable model for the developed drying system. The predicted MRs were in good agreement with the experimental values and the effective moisture diffusivity for ginger was found to be 2.97 × 10–7 m2 s?1. 相似文献
8.
Robert France 《Environmental management》1996,20(2):249-255
Due to assimilation of recycled CO2 from litter decomposition and photosynthetic changes in carbon fractionation at low light levels, the foliage at the base of a forest is often more depleted in13C compared to that exposed to the atmosphere in either the canopy or in open clearings. This is referred to as the canopy effect. African research has indicated that these habitat differences in foliar 13C can be substantial enough to affect the carbon isotope ratios of resident fauna. Previous work documenting a 30-year chronology on moose teeth from Isle Royale National Park indicated a progressive depletion in13C and suggested that this could be due to forest regrowth following extensive burning. The present study examined the assumption implicit in this hypothesis that foliar 13C varies between open and closed boreal forest sites. I found a marginal canopy effect of 2 13C difference between upper canopy and ground flora for a forest in northwestern Ontario and an average difference of 1.2 in under- and mid-story vegetation between closed forests and open clear-cuts. Because of these small differences, the utility of carbon isotope analysis in quantifying temporally integrated exploitation of deforested habitats will be low for northern boreal locations. In denser forests, such as those in the tropics or western North American where the canopy effect can be expected to be much greater, 13C analysis may still offer some promise for determining selection by wildlife of disturbed habitats. 相似文献
9.
The objective of this study was to investigate the efficacy of panel solar cookers in reducing urease activity in full-fat soybeans (Glycine max). Changes in urease activity of soaked (SM), coarse-milled (CM) and whole dry (WM) full fat soybeans were investigated by roasting for 0, 30, 60, 90, 120, 150 and 180 min in multiple reflector panel solar cookers, in a 3 3 3 factorial experiment. Soaking soybeans for 14 h reduced (p<0.05) 1 urease activity by 9%, from 6.58 meqNH3/g DM to 5.98 meqNH3/g DM. After 180 min of solar roasting, urease activity levels had declined by 81%, 67% and 23% in soaked, milled and whole dry soybeans respectively. Full fat soybean urease activity can be reduced faster in soaked than in dry soybeans. Findings suggest that there is potential in using multiple reflector panel solar cookers to reduce urease activity in full fat soybeans. 相似文献
10.
Andrew J. Sexton Gary T. Rochelle 《International Journal of Greenhouse Gas Control》2009,3(6):704-711
MEA solutions were subjected to oxidative degradation at both low and high gas rates. Solutions were degraded with 100 mL/min of 98%O2/2%CO2 with mass transfer achieved by vortexing. Solutions were analyzed for degradation products by IC and HPLC. In a parallel apparatus 7.5 L/min of 15%O2/2%CO2 was sparged through solution, with additional mass transfer achieved by vortexing. A Fourier Transform Infrared (FTIR) analyzer collected continuous gas-phase data on volatile products.Hydroxyethyl-formamide (HEF) and hydroxyethylimidazole (HEI) are the major liquid-phase oxidation products. In the presence of Fe2+ and Cu2+, HEF, HEI, and MEA losses increase by a factor of 3 compared to Fe2+ alone. Cr3+ and Ni2+, two metals present in stainless steel alloys, resulted in MEA losses that are 55% greater. In terms of oxidative degradation potential (greatest to lowest): Cu2+ > Cr3+/Ni2+ > Fe2+ > V5+.Inhibitor A reduces the formation of known products by 90% when catalyzed by Fe2+ and Cu2+ and by 99% with Cr3+/Ni2+. Inhibitor B reduces product rates by 97% and MEA losses by 75%, while a 100:1 ratio of EDTA to Fe2+ completely inhibits oxidation. 相似文献
11.
《Journal of Agricultural and Environmental Ethics》2003,16(4):419-420
Publications Received
Books received 相似文献12.
《Journal of Agricultural and Environmental Ethics》2002,15(4):381-382
Publications Received
Book Received 相似文献13.
Geochemical atlases 总被引:1,自引:0,他引:1
《The Environmentalist》1990,10(4):241-242
Editorial
Geochemical atlases 相似文献14.
Editorial Introduction
From the Editors 相似文献15.
Stewart Lockie Jen Hayward Nell Salem 《Journal of Agricultural and Environmental Ethics》2001,14(2):253-254
Publications Received
Books Received 相似文献16.
Amitrajeet A. Batabyal 《Journal of Agricultural and Environmental Ethics》2003,16(6):625-629
Volume Contents
Conents of Volume 16 相似文献17.
《Resources, Conservation and Recycling》2007,50(4):325-339
In developing countries without the availability of reliable pavement management systems, recycling techniques may offer the best alternative for pavement structural rehabilitation. However, for many government officials and contractors there is a clear understanding of the technical advantages of recycling but not a clear perspective of cost saving. Since cost is a relative value among different regions of any country the following work makes an energy analysis of the construction process of the three different rehabilitation techniques available in Chile. Three different structural pavement rehabilitation alternatives were studied and compared using an energy consumption methodology:
- •Asphalt overlay;
- •Reconstruction;
- •Cold in place recycling with foamed asphalt.
18.
Ben A. Minteer Elizabeth A. Corley Robert E. Manning 《Journal of Agricultural and Environmental Ethics》2004,17(2):111-112
Editorial Introduction
From the Editor 相似文献19.
Editorial Introduction
From the Editors 相似文献20.
Anne C. Bellows 《Journal of Agricultural and Environmental Ethics》2003,16(3):225-226