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1.
本研究的目标是增加关于模型生成数据被用作水质管理的交流工具时,地方利益相关者接受该数据的知识.研究地区选在瑞典西南部的伦讷(R(o)nne(a))河流域.结果表明,模型生成数据起到了联合因素的作用.同时,利益相关者与提供的数据有关,主要问题为未考虑到的污染源、测定污染时缺乏信任、自然变化和延迟效应的影响的不确定性.确定了4组影响利益相关者接受模型生成数据的因素对其实际应用的信心,对所涉及的参与人员或对话资料提供者(如专家、决策者、媒体)的信心,参与者的社会特征(如年龄和职业),和数据的交流方式(如交流的语气、小组的构成、持续时间、对话的地理尺度).对给定的模型生成数据实际应用的公平性的感知,也是接受与否的一个重要因素.  相似文献   
2.
Recognition and understanding of landscape dynamics as a historical legacy of disturbances are necessary for sustainable management of forest ecosystems. This study analyzes spatial and temporal changes in land use and forest cover patterns in a typical mountain forest area in Rize Forest Enterprise of the Northeastern part of Turkey. The area is investigated by evaluated the temporal changes of spatial structure of forest conditions through spatial analysis of forest cover type maps from 1984 and 2007 using GIS and FRAGSTATS. The quantative evidences presented here showed that there were drastic changes in the temporal and spatial dynamics of land use/forest cover. As an overall change between 1984 and 2007, there was a net decrease of 2.30% in total forested areas. On one hand, productive forest areas decreased 12,506 ha, on the other hand, degraded forest areas increased 14,805 ha. In examining the changes of crown closure and development stages of forest ecosystem during the study period, the forest stand area with medium crown closures increased. Regenerated area increased while the other development stages were left to grow to mature development stages in the period. These results regarding to crown closure and development stage showed that forest quality has increased but total forest areas decreased. This is partially due to out-migration of rural population in Rize and Cayeli towns. In terms of spatial configuration, analysis of the metrics revealed that landscape structure in Study area had changed substantially over the 23-year study period, resulting in fragmentation of the landscape as indicated by the large patch numbers and the smaller mean patch sizes due to heavy timber subtraction, illegal cutting, and uncontrolled stand treatments.  相似文献   
3.
The aim was to investigate the impact of atmospheric pollen in determining allergic rhinitis. It was conducted with 130 patients with allergic rhinitis in three different sites in Eskisehir, Turkey, in 2000-2001, using a gravimetric method with a Durham sampler. Skin prick test results, the symptoms of patients and their findings all confirmed the presence of allergic reactions to pollen allergens in the patients observed. During the period, a total of 47,082 pollen grains/cm(2) belonging to 45 taxa were recorded. Of the total pollen grains, 81.0% were arboreal and 18% non-arboreal. The majority of the investigated pollen grains were from Pinaceae, Salix spp., Chenopodiaceae/Amaranthaceae, Cupressaceae and Poaceae. Pollen concentrations reached the highest level in May (54.36%). The pollen allergens provoking severe sensitization were grasscereal mixtures (58.5%), followed by arboreals (33.8%). All patients (100.0%) were sensitive to grass. This study emphasizes the significance of determining the types and concentrations of pollen with a view to comparing changes in highly concentrated allergens.  相似文献   
4.
This study is focused on the preparation, characterization, and determination of thermal properties and thermal reliability of paraffin/polypropylene (PP) composite as a novel form-stable phase change material (PCM) for thermal energy storage applications. In the composite, paraffin acts as a PCM when PP is operated as supporting material. The composites prepared at different mass fractions of paraffin (50, 60, 70, 80, and 90 w/w%) by solution casting method were subjected to leakage test by heating the composites over the melting temperature of the PCM. The paraffin/PP composite (70/30 w/w%) is found as the maximum paraffin containing composite and was characterized using Fourier transform infrared spectroscopy, optic microscopy, differential scanning calorimetry (DSC), and thermal gravimetric analysis (TGA) techniques. DSC analysis indicated that the form-stable paraffin/PP composite melts at 44.77–45.52 °C and crystallizes at 53.55–54.80 °C. It has latent heats of 136.16 and −136.59 J/g for melting and crystallization, respectively. These thermal properties make it potential PCM for latent heat thermal energy storage (LHTES) purposes such as solar space heating applications. Accelerated thermal cycling tests indicated that the form-stable PCM had good thermal reliability. TGA also showed that the form-stable PCM degrades in two distinguishable steps and had good chemical stability.  相似文献   
5.
Alkan Olsson J  Berg K 《Ambio》2005,34(7):507-512
The objective of this study was to increase the knowledge of local stakeholders' acceptance of model-generated data when used as a communication tool in water quality management. The R?nne? catchment in the southwest of Sweden was chosen as the study area. The results indicate the model-generated data served as a uniting factor. Simultaneously, the stakeholders were concerned with presented data, the main problems being sources of pollution, which were not accounted for, lack of trustworthiness when measuring pollution, and the uncertainty of the impact of natural variation and delayed effects. Four clusters of factors were identified as influencing stakeholders' acceptance of the model-generated data: confidence in its practical applications, confidence in the people involved in or providing material for the dialog (such as experts, decision-makers, and media), the social characteristics of the participants (such as age and profession), and the way of communicating the data (such as tone of communication, group composition, duration, and geographical scope of the dialog). The perception of the fairness of the practical application of given model-generated data was also an important factor for acceptance.  相似文献   
6.
FeSO4·xH2O is generated in large amounts in galvanizing workshops. It can be reutilized by conversion to Fe2O3. In this study, the recovery of Fe2O3 from FeSO4·xH2O formed in the galvanizing process has been examined. The experimental work was carried out at various temperatures and times in the oxidizing medium. The reaction temperatures and times were selected as 450, 500, 550, 600, 650, 700, 800 and 900°C, and 15, 30, 45, 60, 90 and 120 minutes, respectively. In order to determine the amount of Fe2O3, a titrimetric method was applied. The reaction products were characterized by means of IR and XRD techniques.The extent of conversion is low at temperatures below 650°C. Almost all of the iron (II) sulfate in the original sample was converted to iron(III) oxide at 650°C (120 min), 700°C (90 min), 800°C (60 min) and 900°C (45 min).  相似文献   
7.
The study was attempted to produce activated carbons from palm oil mill effluent (POME) sludge. The adsorption capacity of the activated carbons produced was evaluated in aqueous solution of phenol. Two types of activation were followed, namely, thermal activation at 300, 500 and 800%, and physical activation at 150% (boiling treatment). A control (raw POME sludge) was used to compare the adsorption capacity of the activated carbons produced. The results indicated that the activation temperature of 800℃ showed maximum absorption capacity by the activated carbon (POME 800) in aqueous solution of phenol. Batch adsorption studies showed an equilibrium time of 6 h for the activated carbon of POME 800. It was observed that the adsorption capacity was higher at lower values ofpH (2--3) and higher value of initial concentration of phenol (200--300 mg/L), The equilibrium data were fitted by the Langmuir and Freundlich adsorption isotherms. The adsorption of phenol onto the activated carbon POME 800 was studied in terms of pseudo-first and second order kinetics to predict the rate constant and equilibrium capacity with the effect of initial phenol concentrations. The rate of adsorption was found to be better correlation for the pseudo-second order kinetics compared to the first order kinetics.  相似文献   
8.
In this study, a challenging preconcentration/separation method based on the sorption of manganese on ethylene glycol dimethacrylatemethacrylic acid copolymer (EGDMA-MA) treated with ammonium pyrrolidine dithiocarbamate (APDC) and its slurry analysis by electrothermal atomic absorption spectrometry was described. Optimum conditions for quantitative sorption, as well as for preparing a homogeneous and stable slurry were investigated. A 100-fold enrichment factor could be reached. The analyte element in certified sea-water and bovine-liver samples were determined in the range of 95% confidence level. The proposed technique is fast, simple, and the risk of contamination is low. The limit of detection of the method for manganese in the slurry of the blank subjected to the proposed procedure was 0.07 μg L?1 (3δ, N:10) corresponding to 0.56 μg kg?1 slurry.  相似文献   
9.
The productivity of forest sites has been indirectly determined with solo wood production objective in forest management. Forest site productivity should, however, be determined directly in order to implement ecosystem based multipurpose forest management philosophy. This article tackles the problem in distinguishing and mapping forest sites using both direct method and indirect method in Genya Mountain located in central of Artvin State Forest Enterprise. About 112 sample plots were designed and distributed over the area. In each sample plot, soil samples were collected and the classical timber inventory measurements were taken. According to direct method, Soil Moisture Regime (SMR) method is preferred due to a water deficiency in the study area. Water holding capacity was used as an essential criterion for the classification of the forest site. Forest site classifications were assigned regarding the physiographic factors such as landform, aspect, and slope. Five different forest sites classes; dry, moderate fresh, fresh, humid and hygric were determined. According to direct method, the guiding curve was used to generate anamorphic site index (SI) equations and three site index classes; good (SI=I–II), medium (SI=III) and low (SI=IV–V) were determined. Some important differences between the methods were realized. The forest sites determined with site index estimation method indicate that site index I and II is 505.99 ha, III 1095.79 ha and IV and V 992.95 ha, whereas forest sites determined with direct method related to dry site of 937.58 ha, moderate fresh site of 931.90 ha, fresh site of 1,797.71 ha, humid site of 80.48 ha and hygric site of 356.55 ha. The forest site maps of both methods were created using GIS functions. The forest sites of open and degraded areas should be determined according to direct method.  相似文献   
10.
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