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Material Balance for Stepwise Extraction of Freshwater Algae Biomass with Heavy Metal Sequestration

Abstract

During our studies concerning the isolation of sulfated polysaccharides (SPs) from freshwater algae species widespread in Poland, an improved overall extraction methodology has been developed. This new, multi-step procedure allows for obtainment of several fractions that could find use in cosmetic and food industries, with the final one containing the valuable SPs, important both from economic and scientific perspective. Moreover, the process allows for easy use of typical chelating agents to remove harmful heavy metal ions without important losses in natural compounds of interest. Furthermore, a material balance has been established for said process, allowing for its easier implementation on bigger scales, and highlighting the areas which could still be improved to positively affect the final time-cost ratio of the methodology. Combined with previously published information concerning the detailed composition of obtained fractions, we aim to provide a robust and informative outlook on the potential of native freshwater algae species as cheap, raw and easily purifiable resource, usable in a number of important industries. According to the mass balance, nearly 5 % of dry mass of Cladophora glomerata is extractable with ethanol and this fraction consists mostly of fatty acids, phenolics and pigments. Another 5 % of mass can be isolated as pure SPs from aqueous fraction. Additionally, calcium from natural incrustations on the surface of C. glomerata amounts to 17 % of dry material weight and can be reclaimed from acidic wash by simple precipitation; such calcium salts have garnered significant interest as nutritional supplements.

Open access
Possibility of Carbon Dioxide Sequestration by Catch Crops

Abstract

The global fluxes of carbon in the ecosystem of Earth, with particular attention drawn to the cycle of CO2 were characterised. The sequestration of carbon dioxide in the biomass of plants, especially the ones which can be cultivated as catch crops is described. It was shown that the cultivation of catch crops may play an important role in the mitigation of CO2 emissions.

Open access
Prediction of Water Quality in Riva River Watershed

Abstract

The Riva River is a water basin located within the borders of Istanbul in the Marmara Region (Turkey) in the south-north direction. Water samples were taken for the 35 km drainage area of the Riva River Basin before the river flows into the Black Sea at 4 stations on the Riva River every month and analyses were carried out. Changes were observed in the quality of water from upstream to downstream. For this purpose, the spatial and temporal variations of water quality were investigated using 13 water quality variables with the ANOVA test. It was observed that COD, DO, S and BOD were important in determining the spatial variation. On the other hand, it was found out that all the variables were effective in determining the temporal variation. Moreover, the correlation analysis which was carried out in order to assess the relations between water quality variables showed that the variables of BOD-COD, BOD-EC, COD-EC, BOD-T and COD-T were correlated and the regression analysis showed that COD, TKN and NH4-N explained BOD and BOD, NH4-N, T and TSS explained COD by approximately 80 %. Consequently, the Artificial Neural Network (ANN), Decision Tree and Logistic Regression models were developed using the data of training set in order to predict the water quality classes of the variables of COD, BOD and NH4-N. Quality classes were predicted for the variables by inputting the data of testing set into the developed models. According to these results, it was seen that the ANN was the best prediction model for COD, the Decision Tree for BOD and the ANN and Decision Tree for NH4-N.

Open access
Trace Metal Concentrations in Pleurozium Schreberi and Taraxacum Officinale Along the Road No. 7

Abstract

The aim of this study is to test two plant species, the common dandelion Taraxacum officinale and moss Pleurozium schreberi, as bio monitors of trace metal pollution emitted by motor vehicles. The samples of the moss Pleurozium schreberi (green segments) and the common dandelion Taraxacum officinale (leaves) were collected within 12 transects along the state road No. E77 near Chyzne, Sothern Poland. The transects were located on the eastern and western side of the road (downwind and upwind towards prevailing winds), at the following distances from the road: 5, 50, 100, 300 500 and 600 m. Total concentrations of Cr, Cu, Ni, Pb, Sb and Zn in the plant material were determined. The studied species accumulated trace metals in the similar amounts. Statistically significant differences in metal concentrations between two plant species were observed only in the case of Cu and Pb. Copper concentrations were higher in the common dandelion, while the moss Pleurozium schreberi accumulated considerably higher amounts of Pb. There is a statistically significant negative correlation between the trace metal concentrations in plants and the distance to the road. There are also statistically significant differences in concentrations of Cr, Cu, Ni, Pb and Zn in the common dandelion between the samples collected from the opposite sides of the road: upwind/downwind towards the prevailing wind direction at the distance up to 300 meters. The concentrations are higher on the downwind side of the road.

Open access
Using a Novel Method to Evaluate the Performance of Human Resources in Green Logistics Enterprises

Abstract

The essence of low-carbon logistics is to make logistics capacity grow moderately to meet the requirements of social and economic developments and the goals of energy conservation and carbon reduction through logistics planning and policies, logistics rationalization and standardization, logistics informationization, low-carbon logistics technologies, etc. This study evaluates the performances of human resources in low-carbon logistics enterprises from three assessment facets: work ability, work performance, and work attitude. It adopts the AHP method to reasonably determine an indicator system of performance evaluation and its weight to avoid certain human-caused bias. According to the results herein, the low-carbon work attitude of the case company in recent years has produced good performance, but its low-carbon work performance and low-carbon work ability are both poor. The case company should practically implement and strengthen these indicators so as to enhance human resource performance in low-carbon logistics enterprises. This study establishes a human resources performance evaluation system for low-carbon logistics enterprises to measure the low-carbon working ability, work performance, and working attitude of their general staff. In this way, enterprises may understand their development status, improve development plans, and formulate the best human resources management and development decisions, thus positively guiding their future development.

Open access
Bacillus subtilis BS-2 and Peppermint Oil as Biocontrol Agents Against Botrytis cinerea

Abstract

The purpose of this study was to assess the activity of Bacillus subtilis BS-2 and peppermint oil against Botrytis cinerea. In this study parameters such as the age and the density of the bacterial culture and the incubation temperature were taken into consideration. Furthermore, the cellulolytic activity of the bacterium was determined. The effect of peppermint oil was evaluated at a concentration range of 0.5-4.0 %. The research was conducted with a dual culture plate method. The influence of B. subtilis BS-2 and peppermint oil on the growth of B. cinerea was evaluated based on the growth rate index. It was noted that the bacterial culture occurred at an initial density of OD 560 = 1.0, cultivated at 30 °C for 48 hours demonstrated the strongest antagonistic effect (57.07 % inhibition). Furthermore, it was observed that the highest cellulolytic activity occurred on the bacteria incubated for 48 hours at 37 °C. The effect of mint oil, at the lowest concentration of 0.5-1.0 %, was much weaker on bacterial activity (1.1-12.1 % inhibition). The highest concentration (4.0 %) of mint oil caused the maximum inhibition (31.9 %) of the mycelial growth. B. subtilis BS-2 may be environmental-friendly alternatives for protecting plants against B. cinerea

Open access
Characterisation of Municipal Sewage Sludge as a Soil Improver and a Fertilizer Product

Abstract

In this study, we have determined the main important physical and chemical properties of municipal sewage sludge and compared them to the requirements of the Finnish Fertilizer Product Act and Fertilizer Product Decree in order to assess the potential utilization of this by-product as a fertilizer. Except for Hg (1.4 mg/kg d.m.), the total concentrations of Cd, Cu, Ni, Pb, Zn, Cr and As in our sewage sludge were lower that the Finnish maximum permissible heavy metal concentrations for sewage sludge used as a fertilizer products. However, the sewage sludge may be utilized as a soil improver, a growing media or as a fertilizer product in landfill sites (e.g. surface structures) or in other closed industrial areas, because the above mentioned Finnish limit values are not applied at these sites. If the sewage sludge is to be utilized in these kinds of areas, an environmental permit may be needed. According to BCR-extraction, the lowest release potential (solubility) from the sample matrix was observed for sulphur (58.4 %) and the highest for Cd (100 %).

Open access
Comparative Review of Artificial Light Sources for Solar-Thermal Biomass Conversion Research Applications

Abstract

In recent years solar-thermal methods of waste biomass conversion are promptly gaining on attention. For researchers working in areas that suffer from lack of natural solar power, the choice of proper solar simulator for the study is crucial. Solar simulator consist of artificial light source enclosed in proper housing with optical and cooling system, powered by dedicated power supply. Solar simulators are not only granting independence from external conditions, yet provide possibility of research expand due to tuneable output power and emissive spectrum. Over the years, solar simulators were powered by different types of lamps. Throughout the history, the solar simulators were used mainly in photovoltaic and space research, crystal growth industry, and the material testing. For mentioned purposes, the total thermal output power of simulator was playing secondary role in comparison to urgent need of spectral match, irradiance distribution and beam uniformity with terrestrial or extra-terrestrial sunlight. For thermal applications, solar simulators are facing the challenge of providing high output power, described by high radiant heat flux and high heat flux density over the specified target area. In presented paper the comparison of xenon arc, metal halide lams and tungsten halogen for thermal applications has been presented with emphasis on available thermal power, spectral match with natural sunlight and operational issues. The course of decision taken during the selection of artificial light source for construction of laboratory-scale solar pyrolytic reactor is proposed.

Open access
A Comparison of ETV and LA for the Determination of Trace Elements in Solid Samples by MIP OES

Abstract

The performance of electrothermal vaporization (ETV) and laser ablation (LA) of dry aerosols as sample introduction systems for microwave induced plasma optical emission spectrometry (MIP OES) are compared and evaluated in terms of detection limits, precision and accuracy for the determination of trace elements (Ca, Cd, Cu, Fe, Mg, Mn, Sr, Zn) in the same solid micro samples. In MIP OES both radiation sources can be independently adjusted to optimize the sampling process and then its subsequent excitation. A univariate approach and simplex optimization procedure were used to obtain the best signal/noise (S/N) ratio and derive analytical figures of merit. A comparison using a Student’s t-test between the results obtained by both ETV/LA-MIP OES methods for trace elements, and concentrations in standard reference material (SRM) and certified reference materials (CRMs) showed that there was no significant differences on a 95 % confidence level. The detection limits of the tested elements in solid samples by ETV/LA-MIP OES were in the range of 0.1 to 11 µg g−1 for all elements determined, while the corresponding absolute values in the range of ng. The precision of the results for ETV-MIP OES and LA-MIP OES varied between 2 and 4 % and 3 and 7 %, respectively. The linear dynamic ranges in the ETV/LA-MIP OES are extend over three decades of concentration. The methods were validated by the analysis of NIST SRM 2711Montana Soil, NRCC CRM PACS-2 Marine Sediment and NRCC CRM TORT-2 Lobster Hepatopancreas of different matrix composition and by the standard addition technique.

Open access
Designing a Pond and Evaluating its Impact Upon Storm-Water Quality and Flow: A Case Study in Rural Australia

Abstract

Storm-water management is a common concern in rural catchments where development-related growth causes increases of storm-water flows. Greater magnitude and frequency of storm-water create greater challenges for mitigating storm-water damage and improving water quality. The concept of Blue-Green Infrastructure (BGI) as a solution incorporates a wide range of applicable components with the aim of minimizing the effect of catchment development on flow regimes without changing the watershed morphology. BGI components manage storm-water by decreasing impermeable cover and expanding natural and semi-natural systems to store water or recharge and filter storm-water into the ground. In this paper, guidelines for designing a pond as a component of BGI are provided and, configuration and size of the pond are determined. Moreover, the impacts of the designed pond on storm-water peak flow and quality are assessed for the Tarwin catchment, State of Victoria, Australia. The results indicate that the introduction of the pond would have reduced outfall inflow by 94 % and would have achieved the reduction of 88.3, 75.5 and 50.7 % for total suspended solids, total phosphorus, and total nitrogen respectively, during the extreme weather event in June 2012.

Open access