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991.
While oil prices raise and the supply remains unsteady, it may be beneficial to use the high content of energy available in food processing wastes, such as cheese whey waste, by converting it to bioenergy. As well, there have been many new waste biotreatment technologies developed recently, which may well be used directly to food processing wastes. Microbial fuel cell represents a new technology for simultaneous use of waste materials and bioelectricity generation. In this study, bioelectricity generation with whey degradation was investigated in a two-chamber microbial fuel cell with mediators. E.coli was able to use the carbohydrate found in whey to generate bioelectricity. The open-circuit voltage in absence of mediator was 751.5mV at room temperature. The voltage was stable for more than 24 h. Riboflavin and humic acid were used as conceivable mediators. The results showed that humic acid was a few times more effective than Riboflavin. Additionally, four chemicals employed as catholyte. Based on polarization curve, FeCl3 (III) was the best. Maximum power generation and current were 324.8 μW and 1194.6μA, respectively.  相似文献   
992.
Introduction WithGPSreceiversmountedonLEOsatel lites,GPSoccultationeventscanbeobserved.Theobservablesarevaluableforatmospheric monitoringandweatherforecasting.Whenpre paringtobuildupanLEOsatelliteoccultation observationsystem,theevaluation,designand imple…  相似文献   
993.
Introduction Theprimarymissionofanelectronicwarfare dentificationsystemistodetectthepresenceof hostileemittersandidentifytheemittersas quicklyandaccuratelyaspossible[1,2].Thecur entrecognitionalgorithmsarebasicallymatc hingalgorithms.Theyperformasequenceo…  相似文献   
994.
IntroductionDVGE was first proposed by Lin Hui and GongJianhua in 1999. DVGE“is not only an advanceddevelopment of geographic information science, butalso a distributed three dimensions virtual environ-ment. It is based on avatar and has many charac-ters…  相似文献   
995.
IntroductionChina is the third richest country in the world ofmineral resources with a total potential value of 11trillion USdollars. Yunnan Provincce is one of theimportant metallogenic belts for nonferrous and pre-cious metal deposits[1].Mineral source …  相似文献   
996.
System dynamics (SD) theory has long been deployed in modeling complex non-linear interrelationships but, so far it has not been common to do the kind of modeling in support of bringing environmental sustainability policies to practice. This is largely because the challenge of including spatial data has not yet been well met. Potential for adoption of SD and GIS methods in combination is exemplified with the results of a decision-support exercise designed for simulation and prediction of the dynamic inter-relationships between socio-economic development and environmental quality for the “Wen, Pi, Du” county in Sichuan province, southwestern China.  相似文献   
997.
Potentiometric titrations were used to measure conditional stability constants of UO22+-fulvic acid and UO22+-humic acid complexes. Both 2:1 and 1:1 COO-:UO22+ binding were observed. With decreasing metal concentration (2.5·10−4-6.25·10−5 M) increasing amounts of UO22+ were in the form of 1:1 humate complexes and 2:1 fulvate complexes. Despite the high nitrogen content and the low acidic OH group content, the successive stability constant values were similar to those determined for divalent cations associated with fulvic and humic compounds isolated from soils. Stability constant values increase simultaneously with increasing ionization of the humic (or fulvic) acid polyelectrolytes and with decreasing metal concentration.  相似文献   
998.
999.
1 IntroductionSpatialrelationsqueryisoneofbasicfunctionsinGIS’sapplication .MostofcurrentcommercialGISscanonlyqueryspatialrelationsforspatialob jectswithoutanyerrororuncertainty ,forexample ,tousecomputation geometryalgorithmtodeter minewhetherapointfalls…  相似文献   
1000.
Dissolved load of the Loire River: chemical and isotopic characterization   总被引:5,自引:0,他引:5  
The Loire River, with one of the largest watersheds in France, has been monitored just outside the city of Orleans since 1994. Physico-chemical parameters and major and trace elements were measured between 2-day and 1-week intervals according to the river flow. The sampling site represents 34% of the total Loire watershed with 76% silicate rocks and 24% carbonate rocks.

Elements are transported mainly in the dissolved phase with the ratio of total dissolved salts (TDS) to suspended matter (SM) ranging between 1.6 and 17.4. Chemical weathering of rocks and soils are thus the dominant mechanisms in the Loire waters composition. The highest TDS/SM ratios are due to dissolved anthropogenic inputs. The database shows no link between NO3 content and river flow. The Na+, K+, Mg2+, SO42−, and Cl concentrations are seen to decrease with increasing discharge, in agreement with a mixing process involving at least two components: the first component (during low flow) is concentrated and may be related with input from the groundwater and sewage station water, the second component (during high flow) is more dilute and is in agreement with bedrock weathering and rainwater inputs. A geochemical behaviour pattern is also observed for HCO3 and Ca2+ species, their concentrations increase with increasing discharge up to 300 m3/s, after which, they decrease with increasing discharge. The Sr isotopic composition of the dissolved load is controlled by at least five components — a series of natural components represented by (a) waters draining the silicate and carbonate bedrock, (b) groundwater, and (c) rainwaters, and two kinds of anthropogenic components.

The aim of this study is to describe the mixing model in order to estimate the contribution of each component. Finally, specific export rates in the upper Loire watershed were evaluated close to 12 t year−1 km−2 for the silicate rate and 47 t year−1 km−2 for the carbonate rate.  相似文献   

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