Sorption Mechanism of Lead Ions From Aqueous Solution By Imperata Cylindrica Dried Leaf Particle: Effect of Temperatures

This study was conducted to investigate the sorption mechanism of Pb2+ ions from aqueous solution onto Imperata cylindrica (IC) dried leaf particles. The effect of temperatures (30, 35 and 40oC) was scrutinised from a batch adsorption system using a synthetic liquid waste containing Pb2+ ions. Adsorption of lead ions mechanism was investigated by intraparticle diffusion model. The results showed that higher adsorption rate occurred at higher temperature, and obeyed the pseudo second order adsorption model. The overall rate of lead uptake was found to be controlled by external mass transfer at the beginning of adsorption, then gradually changes to intraparticle diffusion controlled at a later stage. The intraparticle diffusion constant increased with increasing temperature. The values of effective diffusion coefficient (Di) increased at higher temperatures, which were 5.5466 × 10−9, 6.8215 × 10−9, and 7.3726 × 10−9 m2/s at 30, 35, and 40 ◦C, respectivel

Experimental and Modeling Studies of the Reaction Kinetics of Alkaline-Catalyzed used Frying Oil Glycerolysis using Isopropyl Alcohol as a Reaction Solvent

An alkaline catalyzed glycerolysis of used frying oil using sodium hydroxide and isopropyl alcohol as solvent was investigated. A reaction kinetic model considering glycerol-triglyceride solubility and a second order kinetic mechanism was also developed. The effect of variations in glycerol to used frying oil molar ratio (RGO = 2:1 to 4:1) and temperature (60 to 80ºC) on the rate of reaction were investigated, while the isopropyl alcohol to used frying oil ratio (2:1 v/w) and the concentration of catalyst (3 wt% based on used frying oil) were held constant. Results showed that both RGO and temperature affected the glycerolysis reaction kinetic, with the effect of RGO was found to be superior. The proposed model showed its good agreement with the experimental data. Glycerolysis at RGO = 3:1 and 80ºC in 90 min was found to be a relatively good condition, where 91.03% of tryglceride was converted into MG

Hydrological factors influencing sediment concentration fluctuations in small drainage basins

Although sediment concentrations measured in two contrasting streams in East Yorkshire fluctuate in response to similar hydrological factors, the effectiveness of these factors reflects the environmental characteristics of the drainage basins. Consequently, regression relationships used to predict sediment concentrations in individual streams are not directly applicable outside the region in which they were developed. The sensitivity of sediment concentration variations to environmental conditions makes long term estimates of denudation of limited value

Forecasting the Impact on Demand Management Strategies: Results from Saturn Model Tests (Part 1)

This report provides a summary of the network modelling which has been undertaken as part of the "Transport Demand Management in Historic Cities" research project. This report describes the development of techniques which enable the strategies of the project, as described in the document "Proposed Strategy Measures - Consultation Document" to be modelled. The results presented within this report should not be taken as the final results for the project. However, the results can be read as a first round of results indicating that the model is capable of forecasting the impacts of the strategies. Furthermore, these results provide an indication of the possible impacts of the strategies and should be used as the basis of discussion with regard to the implications of introduction of such strategies and the manner in which the strategies could he combined

A new portable 3-D gyroscope system for the evaluation of upper limb function

This study aims to develop a lightweight, portable and cost effective system for 3D motion analysis of the upper limb which can be readily applied within a clinical environment

The Rhone Caesar

It was probably between 49 and 46 BC, when Caesar had close relationships with Arles that, according to the French archaeologist Luc Long, who found it in 2007 after struggling with poor visibility, strong currents and the catfishes of Rhone, the famous marble bust of Arles had been carved. This beautiful portrait, discovered in the depths of the right bank of the river near Arles, has been undoubtedly attributed by Long to Julius Caesar. ... Here we compare the Arles bust with some others and propose the application of image processing and multimodal biometric systems to the ancient artifac

Investigating bias in the application of curve fitting programs to atmospheric time series

The decomposition of an atmospheric time series into its constituent parts is an essential tool for identifying and isolating variations of interest from a data set, and is widely used to obtain information about sources, sinks and trends in climatically important gases. Such procedures involve fitting appropriate mathematical functions to the data. However, it has been demonstrated that the application of such curve fitting procedures can introduce bias, and thus influence the scientific interpretation of the data sets. We investigate the potential for bias associated with the application of three curve fitting programs, known as HPspline, CCGCRV and STL, using multi-year records of CO2, CH4 and O3 data from three atmospheric monitoring field stations. These three curve fitting programs are widely used within the greenhouse gas measurement community to analyse atmospheric time series, but have not previously been compared extensively. The programs were rigorously tested for their ability to accurately represent the salient features of atmospheric time series, their ability to cope with outliers and gaps in the data, and for sensitivity to the values used for the input parameters needed for each program. We find that the programs can produce significantly different curve fits, and these curve fits can be dependent on the input parameters selected. There are notable differences between the results produced by the three programs for many of the decomposed components of the time series, such as the representation of seasonal cycle characteristics and the long-term (multi-year) growth rate. The programs also vary significantly in their response to gaps and outliers in the time series. Overall, we found that none of the three programs were superior, and that each program had its strengths and weaknesses. Thus, we provide a list of recommendations on the appropriate use of these three curve fitting programs for certain types of data sets, and for certain types of analyses and applications. In addition, we recommend that sensitivity tests are performed in any study using curve fitting programs, to ensure that results are not unduly influenced by the input smoothing parameters chosen. Our findings also have implications for previous studies that have relied on a single curve fitting program to interpret atmospheric time series measurements. This is demonstrated by using two other curve fitting programs to replicate work in Piao et al. (2008) on zero-crossing analyses of atmospheric CO2 seasonal cycles to investigate terrestrial biosphere changes. We highlight the importance of using more than one program, to ensure results are consistent, reproducible, and free from bias

Testing the use of bomb radiocarbon to date the surface layers of blanket peat

The recently formed surface layers of peatlands are archives of past environmental conditions and can have a temporal resolution considerably greater than deeper layers. The low density and conditions of fluctuating water table have hindered attempts to construct chronologies for these peats. We tested the use of the radiocarbon bomb pulse to date recently accumulated peat in a blanket mire. The site was chosen because the peat profiles contained independent chronological markers in the form of charcoal-rich layers produced from known burning events. We compared chronologies derived from accelerator mass spectrometry C-14 analysis of plant macrofossils against these chronological markers. The bomb C-14-derived chronologies were in broad agreement with the charcoal dating evidence. However, there were uncertainties in the final interpretation of the C- 14 results because the pattern of C-14 concentration in the peat profiles did not follow closely the known atmospheric C-14 record. Furthermore, samples of different macrofossil materials from the same depth contained considerable differences in C-14. Suggested explanations for the observed results include the following: i) minor disturbance at the site, ii) in-situ contamination of the C-14 samples by carbonaceous soot, and iii) differential incorporation of plant material during blanket peat growth