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91.
It is well known that dilute sulfuric acid pretreatment of the lignicellulosisc biomass is an effective approach used for the production of the ethanol. However, there are less studies on the biogas production from the pretreated lignocellulosics and hardly data available on the codigestion of cattle manure with the pretreated lignocellulosisc material. The aim of this study was to evaluate biomethane production potential of codigestion of cattle manure with dilute acid pretreated lignocellulosic biomass. Sugarcane bagasse and rice husk was pretreated with dilute sulfuric acid or phosphoric acid at 121°C for 20 minutes and subsequently subjected to anaerobic digestion alone or codigested with cattle manure.

The results showed that codigestion of 1% phosphoric acid pretreated rice husk with cattle manure led to the highest methane production of 115 Nmlg?1VS while monodigestion of cattle manure and phosphoric acid pretreated rice husk produced 98 and 87 Nmlg?1VS, respectively. An inhibition was observed in anaerobic digestion of sulfuric acid pretreated rice husk and sugarcane bagasse during monodigestion and codigestion with cattle manure.

The study concludes that dilute phosphoric acid pretreated lignocellulosics like sugarcane bagasse and rice husk can be used as a cosubstrate with cattle manure in anaerobic digestion for enhanced methane production. Dilute sulfuric acid pretreatment, which is effective method for the bioethanol production, causes inhibition during anaerobic digestion of the pretreated lignocellulosics.  相似文献   
92.
Prediction models relating pheromone trap catches of (H) with several onvironmental factors are worked out. It is expected that those models will help overcome indiscriminate use of pesticides.  相似文献   
93.
94.
In this study, some heavy metal concentrations (Pb, Zn, Fe, Cr, Cu), suspended sediment, chemical oxygen demand (COD), biological oxygen demand (BOD), cyanide, phenol, fecal coliform and total coliform water parameters were determined in the streams (Kucuk Melen, Asarsuyu, Ugursuyu, Buyuk Melen and Aksu) of Buyuk Melen Watershed that provides drinking water to Istanbul in Western Black Sea Region of Turkey. Measurements of water quality parameters were done monthly in eleven separate stations (4 in Kucuk Melen Stream, 1 in Asarsuyu Stream, 1 in Ugur Stream, 1 in Aksu Stream and 4 in Buyuk Melen Stream) from August 2001 to August 2002. The seasonal changes in water quality parameters were evaluated statistically. The results, the parameters, COD, BOD, Pb, Zn, Fe, Cr, Cu, cyanide, fecal coliform, total coliform and suspended sediment showed significant differences among seasons and streams (ANOVA; P <0.05). According to Turkish Standarts (TS) 266, European Union (EU) and World Health Organization (WHO) criteria, the maximum values of each parameter in streams within the Buyuk Melen watershed are recorded and evaluated in this study.  相似文献   
95.
Sarikaya R  Yilmaz M 《Chemosphere》2003,52(1):195-201
A 96-h LC(50) values of 2,4-D [(2,4-dichlorophenoxy)acetic acid], a common contaminating agricultural herbicide, were determined on the adult common carp (Cyprinus carpio L., 1758; Pisces, Cyprinidae). The study was conducted in two stages using 130 carp. The data obtained were statistically evaluated by the use of the EPA computer program based on Finney's Probit Analysis Method and a 96-h LC(50) value for C. carpio L., 1758 was found to be 63.24 mg/l in a static bioassay test system. 95% lower and upper confidence limits for the LC(50) were 55.03 and 71.92 mg/l, respectively. Water temperature was 17+/-1 degrees C. Behavioral changes of the above mentioned species were examined for various herbicide concentrations.  相似文献   
96.
The objectives of this study were to assess land suitability andto monitor the spatial and temporal changes in land use types (LUTs)by using GIS. The study was conducted in an irrigated area of 920ha, located in the East Mediterranean region of Turkey. Archiveddata of LUTs were utilized. Data analysis was conducted by usingArcInfo and ArcView GIS softwares. The land characteristics werecompared with land requirements of present LUTs by taking intoaccount the land evaluation results. Three major soil series andtwelve different LUTs were identified. Corn and citrus were themost planted LUTs in the assessment period. Generated mapsdemonstrated how LUTs changed spatially and temporally. Most LUTswere clustered in certain areas indicating that farmer'sselection of LUTs was affected by their habits and neighbor'sbehavior. Land suitability assessment results indicated thatCanakci and Mursel soil series were found to be highly suitable forall LUTs while Arikli soil series was determined to be moderately suitablecitrus, vegetables and watermelon. Citrus plantationmaps overlaid on soil series maps demonstrated that the citrushas not been planted completely on suitable areas. Landsuitability assessment showed that citrus plantation in Arikliseries would result in 40% yield loss and 58% of land is notused at its potential.  相似文献   
97.
Concentration of Cd, Co, Cr, Ni, Zn, Fe, Mn, Pb and Cu were determinedin biota and sediment samples collected from the Marmara Sea in Turkey. The levels of Zn, Fe, Mn, Pb and Cu in the macroalgae are higher than previous studies in the Marmara Sea. Moreover, Cu and Zn concentrations at the present study are significantly high than Bosphorus and Black Sea algae. The order heavy metal concentrations in the mussel samples was: Fe > Zn > Ni > Mn > Cu > Pb > Cr > Cd > Co. The metal concentrations are generally lower when compared with the Black Sea mussels except Pb. At the same time, concentrations of Pb, Cu and Zn in the mussel species are lower when compared with the results in the Aegean Sea. The ranges of Mn and Cu in the tested fish samples are higher than Black Sea fish. On the other hand, Cd, Co, Cr, Zn and Pb concentrations are lower. The northern coast of the Marmara Sea having the highest metal concentrations in sediments as follows: Co, Cr, Ni, Fe at ?arköy ; Pb, Cu at M. Ere?li; Cd, Zn, Mn at Menek?e. The heavy metal levels in the sediment samples are lower than other areas in the Marmara Sea.  相似文献   
98.
By utilising a relatively underused framework developed by Maurie J. Cohen (1997. Risk society and ecological modernisation alternative visions for post-industrial nations. Futures, 29 (2), 105–119), this theoretical paper joins two of the most debated theories of environmental politics – ecological modernisation (EM) and Ulrich Beck’s risk society thesis – into a unified framework and problematises some of their implicit assumptions to theoretically introduce the notion of a “double-risk” society. In addition, it explains the differences between the traditional “Risk Society” theorised by the German sociologist Ulrich Beck and the newly introduced concept of a “double-risk” society. The arguments put forward in this paper provide some fresh perspectives facilitating the study of the techno-environmental risks and other ecological problems faced by “double-risk” societies. Theoretically, this paper adds to both EM theory and the risk society thesis as the generalisability of their existing versions is limited precisely because they fail to address some important social changes at the global structural level.  相似文献   
99.
Process equipment failures (PEFs) are one of the most important causes of process incidents occurrences. To investigate and prevent the PEFs, in addition to having the previous data, it is necessary to have some resources of the PEFs domain knowledge. Nowadays, PEFs data are usually retrieved from existent databases. Customary databases present only previously stored data of equipment failures but, for carrying out a comprehensive PEFs management it is necessary to have access to the PEFs desired knowledge and not only stored data. This paper aims to offer a knowledge base for the PEFs through adopting an ontological approach and then to use the proposed knowledge base for further applications particularly, process incident investigation activities. Through adding semantic search capability, the proposed knowledge base could upgrade the data presenting feature of the common databases into a knowledge presenting feature. Using this approach, the user would be able to extract the desired knowledge of the PEFs along the virtual stored data of occurred cases. The knowledge extraction process and the data mining of occurred incidents are both necessary for the PEFs investigation.  相似文献   
100.
The biological aerated filter (BAF) system, a new alternative in drinking water treatment, was designed to remove NH4+–N and Mn2+ simultaneously. This study aimed to control the aeration time in the BAF system for simultaneous NH4+–N and Mn2+ removal to achieve the Malaysian effluent quality regulation for drinking water. The experiment was conducted under four strategies of S1, S2, S3 and S4. The results demonstrated that acceptable levels of NH4+–N and Mn2+ were achieved over a 6 h aeration period (S1), producing effluent concentrations of 0.7 mg/L (93.2% removal) and 0.08 mg/L (79.6% removal), respectively. At the initial treatment of S1 and S2, the dissolved oxygen (DO) level rapidly increased until it reached a saturated concentration (6.8 mg/L DO) after 2 h period. Automatic on–off aeration time to maintain 3 mg/L DO set point (S4) resulted with a good effluent quality of NH4+–N and Mn2+ compared with the 2 mg/L DO set point (S3) which did not meet the regulated standard limits. Through the automatic on–off aeration time, the saturated and excessive DO levels in the BAF system can be avoided consequently reduce the wastage of energy and electrical consumption for simultaneous NH4+–N and Mn2+ removal from drinking water treatment.  相似文献   
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