Effects of Starch Sources and Supplementary Materials on Starch Based Foam Trays

Firstly, foam trays were produced from glyoxal cross-linked wheat, potato and corn starches and their mixtures. The most suitable starch type for starch-based foam tray production was selected according to the level of water absorption, density, surface and cross-section micrographs of the foam trays. It was decided that a wheat and potato starch blend was the most suitable starch source for producing the foam trays because they have the lowest water absorption percentage (25.5 ± 0.7%), low density (0.17 ± 0.01 g/cm³) and a smooth surface. Potato–wheat starch foam trays with fibres were produced by adding wheat and wood fibres. Unlike wood fibres addition, wheat fibres significantly decreased the percentage of water absorption (16.63 ± 1.2%) and density (0.115 ± 0.013 g/cm³) of the tray. Also, the trays including wheat fibre had a lighter colour than the wheat–potato starch tray. To further reduce water absorption of the tray, the trays were made by adding two different types of lipids (beeswax or shortening and three different types of filler materials—kaolin, montmorillonite or zinc oxide nanoparticles). According to the level of water absorption of the trays, it was decided that shortening and zinc oxide nanoparticles, in addition to kaolin, were respectively the most suitable lipid and filler materials. The foam trays were produced by adding these supplementary materials. The addition of shortening slightly, zinc oxide nanoparticles moderately and kaolin greatly increased the density of the wheat potato starch tray including fibre. However, the percent of water absorption of the trays containing wheat fibre + shortening or wheat fibre + shortening + zinc oxide nanoparticles decreased 6.4 ± 0.01 and 5.9 ± 0.3%, respectively.     

Analysis of Atmospheric Conditions during Air Pollution Episodes in Ankara,Turkey

ABSTRACT

This paper presents a detailed analysis of the meteorological conditions that are associated with strong air pollution episodes in Ankara, Turkey. Based on climatological and air quality data [SO₂ and TSP (total suspended par-ticulates)] obtained for the winter months during 19891994, the analysis showed that the presence of weak atmospheric pressure gradients and warm air advection were the most important factors leading to high SO₂ and TSP concentrations. In addition, the onset of the high air pollution episodes was generally associated with a trend toward negative vorticity at the 850-hPa level.     

Classification of dimension stone wastes

Purpose

For countries in which the stone industry is well developed, opposition to quarry and plant waste is gradually increasing. The primary step for waste control and environmental management is to define the problem of concern. In this study, natural building stone wastes were classified for the first time in the literature.

Methods

Following on-site physical observations and research at more than 50 quarries and 20 plants, stone wastes were classified as (1) solid, (2) dust and (3) semi-slurry, slurry and cake.

Conclusions

As a result of this study, the characteristics of wastes, their main environmental threats and the industries in which wastes could be used were defined for each group.     

Estimation of Biogas Generation from a Uasb Reactor via Multiple Regression Model

In this study, regression analysis based an estimation model for biogas generated from an up-flow anaerobic sludge blanket (UASB) reactor treating landfill leachate is developed using several leachate parameters, such as pH, conductivity, total dissolved solids, chemical oxygen demand, alkalinity, chloride, total Kjeldahl nitrogen, ammonia, total phosphorus. These landfill leachate parameters are monitorized over a period of 1000 days at 35 ± 1°C in the UASB reactor. In order to develop the best model giving highest estimation performance, eight model equations including different input parameter combinations are analyzed. Based on the results of regression analysis, the best coefficients of the model equation are determined. As a conclusion, the developed model in this study can give accurate biogas amount prediction for the USAB reactor-based leachate treatment system.     

Alkali-silica reactions of mortars produced by using waste glass as fine aggregate and admixtures such as fly ash and Li2CO3

Use of waste glass or glass cullet (GC) as concrete aggregate is becoming more widespread each day because of the increase in resource efficiency. Recycling of wastes is very important for sustainable development. When glass is used as aggregate in concrete or mortar, expansions and internal stresses occur due to an alkali-silica reaction (ASR). Furthermore, rapid loss in durability is generally observed due to extreme crack formation and an increase in permeability. It is necessary to use some kind of chemical or mineral admixture to reduce crack formation. In this study, mortar bars are produced by using three different colors of glass in four different quantities as fine aggregate by weight, and the effects of these glass aggregates on ASR are investigated, corresponding to ASTM C 1260. Additionally, in order to reduce the expansions of mortars, 10% and 20% fly ash (FA) as mineral admixture and 1% and 2% Li(2)CO(3) as chemical admixture are incorporated by weight in the cement and their effects on expansion are examined. It is observed that among white (WG), green (GG) and brown glass (BG) aggregates, WG aggregate causes the greatest expansion. In addition, expansion increases with an increase in amount of glass. According to the test results, it is seen that over 20% FA and 2% Li(2)CO(3) replacements are required to produce mortars which have expansion values below the 0.2% critical value when exposed to ASR. However, usages of these admixtures reduce expansions occurring because of ASR.     

Geoenvironmental behavior of foundry sand amended mixtures for highway subbases

The high cost of landfilling and the potential uses of waste foundry sands have prompted research into their beneficial reuse. Roadways have a high potential for large volume usage of the foundry sands. A laboratory testing program was conducted on soil-foundry sand mixtures amended with cement and lime to assess their applicability as highway subbase materials. The mixtures were compacted in the laboratory at a variety of moisture contents and compactive efforts and subjected to unconfined compression, California bearing ratio, and hydraulic conductivity tests. The environmental suitability of the prepared mixtures was evaluated by analyzing the effluent collected during hydraulic conductivity tests. Finally, required subbase thicknesses were calculated using the laboratory-based strength parameters. The results of the study show that the strength of a mixture is highly dependent on the curing period, compactive energy, lime or cement presence, and water content at compaction. The resistance of foundry sand-based specimens to winter conditions is generally better than that of a typical subbase reference material. Laboratory leaching tests indicated that if these mixtures later come in contact with water that has been discharged directly to the environment (e.g., drainage through asphalt pavement), the quality of water will not be affected.     

A wind-solar PV hybrid power system with battery backup for water pumping in remote localities

After energy, water is the most critical commodity to be made available to people to keep them alive. Saudi Arabia has vast land and people are living in all regions. Most of these are connected to national grid but some are not, especially in remote areas like in the north, south, and west south. Pumping water in remote areas for domestic needs like agriculture and animals beside human needs is essential and require regular power supply. The present idea of wind-PV-Battery hybrid power system based on 100% renewable source is being proposed to utilize and tested in some of the regions on experimental bases. Of the five locations chosen for the purpose, namely Dhahran, Riyadh, Jeddah, Guriat and Nejran, some are good from both wind and solar intensity point of view some have good winds only and some good solar only. Nearly optimal size of PV-Wind water pumping system is determined for each of these sites considering the availability of solar and wind energy distributions throughout the year in these sites. It is shown that the monthly total water pumping capacity when using nearly optimal PV-Wind water pumping system is fairly uniform throughout the year except for the sites of Guriat and Riyadh. In these sites higher water pumping capacity is observed during the spring and summer months. On the other hand the cost of underground water pumping is found to vary between 6 to 12 US¢/m³ for the five sites considered.     

Degradation of fipronil under laboratory conditions in a tropical soil from sirinhaém pernambuco,Brazil

The objective of this research was to assess the degradation of fipronil [5-amino-1-(2,6-dichloro-α,α,α -trifluoro-p-tolyl)-4-trifluoromethylsulfinylpyrazole-3-carbonitrile] in soils from sugar cane fields in Northeastern Brazil. Degradation experiments were carried out under laboratory conditions (controlled temperature and in the dark), where sterile and non-sterile soils (Ustoxs) were incubated [under moisture content of 55% of the water holding capacity (WHC)] and analyzed for fipronil disappearance and metabolite formation. Microbial communities present in the soil degrade fipronil. However, biodegradation seems to be dependent on the bioavailability of the fipronil and the half-life according to the zero-order model. Fipronil degradation rate appeared to be biphasic. Degradation fipronil ranged from 83 days (initial concentration = 978 ng g^{? 1}; short-term experiment) to 200 days (initial concentration = 689 ng g^{? 1}; long-term experiment). This an initial slower rate followed by a faster rate after 90 days of incubation may lead to shorter half-life than that calculated with the zero-order model. The sulfone derivative (an oxidation product) was the predominant metabolite, but the sulfide (a reduction product) and amide (a hydrolysis product) derivatives were also formed under non-sterile conditions after 120 days of incubation. The metabolites underwent further biodegradation, particularly the sulfone derivative. Bioavailability appears to affect fipronil degradation in soils with an effective capacity to adsorb fipronil (such as Ustoxs), while redox potential was important for the formation of metabolites. Despite the fine texture, more aerobic sites were present, thus favoring the formation of the sulfone metabolite over that of the sulfide metabolite. Therefore, microaggregation of Ustoxs, with high clay content, played a very important role in determining the types of metabolites formed.     

Investigation of heavy metal content in the suspended particulate matter and sediments of inner Gokova Bay and creeks

The Bay of Gokova in Southeastern Aegean Sea (Turkey) is important by the potential of agricultural, municipal, and tourism activities. In addition, there is no industrial plant within the area in the Aegean Sea. Kad?n Creek (Azmak) and Ak?ap?nar Creek (Azmak) flowing into the inner Gokova Bay are one of the important factors in determining the character of the inner Gokova Bay. In this study, nine stations were selected in the inner Gokova Bay, Kad?n Creek, and Akcap?nar Creek. The concentrations of Cd, Cu, Fe, Pb, and Zn were measured in suspended particulate matter (SPM) and sediments. The samples of sediments and SPM were collected in between February 2008 and September 2008. The aim of the study is searching the change of concentrations of Cd, Cu, Fe, Pb, and Zn in suspended particulate matter and sediments in the inner Gokova bay, Kad?n Creek, and Ak?ap?nar Creek. It has been identified that the metal concentrations in the creeks are higher than the metal concentrations in the marine environment. It has also been observed that the concentrations of Pb, Cd, and Cu in summer season have been higher than in the winter season, but the concentrations of Fe and Zn have not shown a significant difference between in summer and winter seasons. The obtained results show that the some heavy metals are caused by the agricultural, municipal, and tourism activities operating in the coastal areas and terrestrial environment, and they are transported from the creeks to the Gokova Bay by suspended particulate matter.     

A puzzle over ecological footprint,energy consumption and economic growth: the case of Turkey

Environmental and Ecological Statistics - The paper investigates the non-linear causality from energy consumption and economic growth to ecological footprint for the case of Turkey by employing...