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31.
Cecilia Akselsson Salim Belyazid Gunilla Pihl-Karlsson 《Environmental pollution (Barking, Essex : 1987)》2010,158(12):3588-3595
Nitrogen leaching from boreal and temporal forests, where normally most of the nitrogen is retained, has the potential to increase acidification of soil and water and eutrophication of the Baltic Sea. In parts of Sweden, where the nitrogen deposition has been intermediate to high during recent decades, there are indications that the soils are close to nitrogen saturation. In this study, four different approaches were used to assess the risk of nitrogen leaching from forest soils in different parts of Sweden. Nitrate concentrations in soil water and C:N ratios in the humus layer where interpreted, together with model results from mass balance calculations and detailed dynamic modelling. All four approaches pointed at a risk of nitrogen leaching from forest soils in southern Sweden. However, there was a substantial variation on a local scale. Basing the assessment on four different approaches makes the assessment robust. 相似文献
32.
Coagulation is the most important stage in drinking water treatment processes for the maintenance of acceptable treated water
quality and economic plant operation, which involves many complex physical and chemical phenomena. Moreover, coagulant dosing
rate is non-linearly correlated to raw water characteristics such as turbidity, conductivity, pH, temperature, etc. As such,
coagulation reaction is hard or even impossible to control satisfactorily by conventional methods. Traditionally, jar tests
are used to determine the optimum coagulant dosage. However, this is expensive and time-consuming and does not enable responses
to changes in raw water quality in real time. Modelling can be used to overcome these limitations. In this study, an Adaptive
Neuro-Fuzzy Inference System (ANFIS) was used for modelling of coagulant dosage in drinking water treatment plant of Boudouaou,
Algeria. Six on-line variables of raw water quality including turbidity, conductivity, temperature, dissolved oxygen, ultraviolet
absorbance, and the pH of water, and alum dosage were used to build the coagulant dosage model. Two ANFIS-based Neuro-fuzzy
systems are presented. The two Neuro-fuzzy systems are: (1) grid partition-based fuzzy inference system (FIS), named ANFIS-GRID,
and (2) subtractive clustering based (FIS), named ANFIS-SUB. The low root mean square error and high correlation coefficient
values were obtained with ANFIS-SUB method of a first-order Sugeno type inference. This study demonstrates that ANFIS-SUB
outperforms ANFIS-GRID due to its simplicity in parameter selection and its fitness in the target problem. 相似文献
33.
Pavlo Bekhta Pavlo Lyutyy Salim Hiziroglu Galyna Ortynska 《Journal of Polymers and the Environment》2016,24(2):159-165
The objective of this study was to evaluate some of the properties of experimental composite panels manufactured from waste packaging materials without using any additional binders. Particles from three types of materials, namely Tetra-Pak, food packaging films (FPEF) as recycled stretch wraps, and candy polyethylene wrappers (CPEW) were used at different ratios in the panels at a target density of 900 kg/m3. Modulus of rupture (MOR), screw holding strength and dimensional stability in the form of thickness swelling and water absorption of the panels were determined according to European (EN) standards. Based on the findings in this work it was determined that the ratio of different raw materials significantly influenced overall properties of the samples. The highest MOR value of 15.5 MPa was determined for the samples having 40 % Tetra-Pak and 60 % CPEW particles. Modulus of rupture values of the panels decreased with decreasing content of CPEW in the samples. The increased content of Tetra-Pak particles in the samples also resulted in reduction of their strength characteristics and dimensional stability. Properties of the samples considered in this work satisfied minimum requirements of typical particleboard stated in EN standards. It appears that such waste material would have potential to be used as raw material for value-added composite production using no adhesive in the panels and, therefore, such panels would possibly create significant ecological impact as green product. 相似文献
34.
Mandour Ahmed S. Elsayed Roushdy F. Ali Asmaa O. Mahmoud Ahmed E. Samir Haney Dessouki Amina A. Matsuura Katsuhiro Watanabe Izumi Sasaki Kazuaki Al-Rejaie Salim Yoshida Tomohiko Shimada Kazumi Tanaka Ryou Watanabe Gen 《Environmental science and pollution research international》2021,28(7):7815-7827
Environmental Science and Pollution Research - Copper deficiency (CuD) is a common mineral disorder in ruminants, which causes histomorphological changes in the heart due to disturbances in... 相似文献
35.
36.
Emad S.M.Ameen Abdullrahim Mohd Yusoff Mohd Razman Salim Azmi Aris Aznah Nor Anuar 《应用与环境生物学报》2013,(1):184-188
In this research,the treatability of solids from sanitary landfill leachate by microfiltration membrane was investigated and the fouling of the membrane was carefully studied.Continuous microfiltration process was carried out for 21 h in experimental system involved coagulation with Moringa oleifera followed by filtration using submerged hollow fibre microfiltration membrane (MFM).Coagulation with M.Oleifera,air diffusers and back flush technique were used for preventing or alleviating fouling of the membrane.The hollow fibre MFM showed high removals of 98%,91% and 99% for turbidity,colour and total suspended solids respectively.It was obtained at the beginning of the filtration.However,quality of the filtrate rapidly declined during the filtration process.Fouling was found to proceed according to the classical cake filtration model.Coagulation with M.Oleifera as well as the back-flush technique could not fully restore the deterioration occurred to the membrane. 相似文献
37.
Emil Salim Mathis Wackernagel Justin Kitzes Deborah Cheng Steven Goldfinger James Espinas Dan Moran Chad Monfreda Jonathan Loh Dermont O'Gorman Idy Wong 《世界环境》2006,(4):58-70
亚太区各国已共同做出坚决承诺。矢志迈向可持续发展的目标。我们希望区内所有人民均可拥有更美好的生活,与此同时维护地球拥有的支援万物生长的能力,尊重地球自然资源的极限。面对今日亚太区以至全世界人口持续增长。消费模式不断改变,我们怎样才能实现这个目标? 相似文献
38.
During social evolution, the ovary size of reproductively specialized honey bee queens has dramatically increased while their
workers have evolved much smaller ovaries. However, worker division of labor and reproductive competition under queenless
conditions are influenced by worker ovary size. Little comparative information on ovary size exists in the different honey
bee species. Here, we report ovariole numbers of freshly dissected workers from six Apis species from two locations in Southeast Asia. The average number of worker ovarioles differs significantly among species.
It is strongly correlated with the average mating number of queens, irrespective of body size. Apis dorsata, in particular, is characterized by numerous matings and very large worker ovaries. The relation between queen mating number
and ovary size across the six species suggests that individual selection via reproductive competition plays a role in worker
ovary size evolution. This indicates that genetic diversity, generated by multiple mating, may bear a fitness cost at the
colony level. 相似文献
39.
Vishwakarma Dinesh Kumar Ali Rawshan Bhat Shakeel Ahmad Elbeltagi Ahmed Kushwaha Nand Lal Kumar Rohitashw Rajput Jitendra Heddam Salim Kuriqi Alban 《Environmental science and pollution research international》2022,29(55):83321-83346
Environmental Science and Pollution Research - Dams significantly impact river hydrology by changing the timing, size, and frequency of low and high flows, resulting in a hydrologic regime that... 相似文献
40.
Removal of cadmium from aqueous solutions using 20 species of plant leaves and combinations of these leaves have been studied. Several factors affecting the removal efficiency have been studied. The most efficient types of plant leaves for the removal of cadmium are those of styrax, plum, pomegranate and walnut. The interaction effect of the combined leaf samples on the efficiency of removal of cadmium has been found to be additive in combinations involving styrax plant leaves but seems to be antagonistic in all other combinations. The optimum experimental conditions for removal of cadmium have been found to be at pH 4.1, using high concentrations of naturally dried plant leaves, using ground leaves and to remove cadmium from agitated aqueous solutions. The percentage of metal removed at an initial cadmium concentration of 10mg/l by the most efficient types of leaves have been found to be 85% for styrax leaves, 85% for plum leaves, 80% for pomegranate leaves, 78% for walnut leaves and 77% for meddler leaves. The presence of foreign ions or complexing agents has been found to reduce the efficiency of removal of cadmium by plant leaves. About 80-85% of the cadmium in charged plant leaves has been released under the influence of changing the pH of the solution, addition of competing ions and the addition of EDTA. The results of removal of cadmium by plant leaves have been found to follow the Freundlich adsorption isotherm, first-order reaction with respect to cadmium and to have intra-pore diffusion as the rate-limiting step. 相似文献