Robust optimization evaluation of reliance on locally produced foods

While local food production may be beneficial in terms of developing the local economy and reducing greenhouse gases from transportation, sustainability strategies focused on local food production may generate their own risks due to yield variability. We have developed a robust optimization (RO) model to determine the minimum amount of land (cropland and pasture) required to grow food items that would satisfy a local population’s (accounting for gender and age) calorie and nutrient needs. This model has been applied to Boone County, Missouri, which has a population of approximately 170,000. Boone County is 1790 km², with 16% of the land defined as cropland and 30% defined as pasture. The model includes 27 nutrients from 17 potential foods that could be produced: six fruits and vegetables, five grains and six animal-sourced foods. Yield estimates are based on the predominate methods of agriculture in the USA. We first run our model assuming no variability, using the midpoint yield estimates. Then, to quantify uncertainty in yield for different food types, we use historical yield data over 10 years to estimate this variability and run our RO model under these variability estimates. We compare the two model results to illustrate the impact of data uncertainty on meeting sustainable local food for communities. Solutions suggest that nutrition needs can be met for the Boone County population within the land area defined.     

Effects of fly ash addition on physical properties of porous clay-fly ash composites via polymeric replica technique

The porous composites of clay and fly ash have the potential to be used in many fields, such as catalyst support and gas adsorbents. In this study, various ratios of fly ash (1–2) with different percentage of suspension (50–70 wt%) were applied to produce porous clay-fly ash composites via polymeric replica technique. Fabrication process starts by mixing clay and fly ash in distilled water to form slurry. The process is followed by fully immersing polymer sponge in slurry. The excess slurry is then removed through squeezing. Finally, the sponge coated with slurry is sintered at 500 and 1250 °C for 1 h. It is found that the compressive strength of porous composites improves significantly (0.178–1.28 MPa) when the amount of clay-fly ash suspension mixture (50–70 wt%) increases. The compressive strength of porous composites is mainly attributed to the mullite, quartz and amorphous phase formations. These results are supported by X-ray diffraction analysis. On the other hand, increase in the amount of suspension reduces the apparent density (from 2.44 to 2.32 g/cm³) and porosity (from 97 to 85 %). The reduction in apparent density is believed to be caused by the presence of high fly ash content in porous composites. The melted fly ash cenospheres have closed the internal pores and increased density of samples. Higher suspension level not only reduces porosity, but also increases close pores of the porous composites. The results are justified through the observation from the structures of porous clay-fly ash composites.     

Molecular Transport of Xylene Through Palm Pressed Fibre Filled Low Density Polyethylene: Role of Fibre Content,Alkali Treatment and Particle Size

We report in this paper the transport of an aromatic solvent, xylene through palm pressed fibre filled low density polyethylene composites studied at three different temperatures (40, 60, and 80 °C) by conventional weight-gain method. The diffusion parameters were investigated with special reference to the effect of fibre content, temperature and particle size. The effect of alkali treatment on solvent uptake was also analyzed. The transport coefficients of diffusion, permeation and sorption were determined to evaluate the influence of interface bonding on transport properties. The van’t Hoff relationship was used to determine the thermodynamic parameters and was found that the estimated free energies of sorption were all positive, indicating non-spontaneity of the solubility of PPF/LDPE composites. The first order kinetic rate constant and swelling parameters were also evaluated.     

Biodegradation characteristics of organic matters in swine carcasses under different initial operating conditions of simulated anaerobic lysimeter

This study was aimed to investigate the biodegradation characteristics of organic matters in swine carcasses. The lysimeters were simulated with different initial operating conditions: 30 % volumetric moisture content and no sludge addition for lysimeter A (control), 30 % volumetric moisture content and anaerobic sludge addition for lysimeter B, and 40 % volumetric moisture content and anaerobic sludge addition for lysimeter C. The degradation efficiency (18.4 %) of lysimeter B was higher than that (15.2 %) of lysimeter A due to anaerobic sludge addition. Lysimeter B showed higher CH₄ yield (15.6 L/kg VS) and CH₄ production rate (0.41 L/kg VS days) compared to lysimeter A by 31 % and 14 %, respectively. In addition, the degradation efficiency improved from 18.4 % (lysimeter B) to 26.3 % (lysimeter C) by increasing volumetric moisture content. The CH₄ yield (22.9 L/kg VS) and CH₄ production rate (0.68 L/kg VS days) of lysimeter C were higher than those of lysimeter B, respectively. Total organic carbon (TOC) removed in lysimeter C was converted to leachate (20.3 %) and gas (6.0 %), whose values were higher than those of lysimeter A and B. These results demonstrated that the proper control of initial operating conditions could accelerate the anaerobic degradation of organic matters in swine carcasses.     

Facile Preparation of Chitosan Films for High Performance Removal of Reactive Blue 19 Dye from Aqueous Solution

This study aimed at finding effective strategies for high-performance removal of reactive blue 19 (RB19) dye from aqueous solution. Chitosan (CS) films had been prepared by using solvent casting with mild drying for this purpose. The CS films were characterized by X-ray diffraction, field-emission scanning electron microscopy, and Fourier transform infrared (FTIR) spectroscopy. The performance of RB19 removal using CS were evaluated by varying contact time, solution pH, initial dye concentration, and adsorbent dosage. Adsorption isotherms, kinetics, and desorption were investigated by batch experiments. Results showed that CS films exhibited the optimal adsorption performance for RB19 removal and high maximum adsorption capacities of RB19, which were 799 and 822.4 mg g^?1 at 20 and 40 °C, respectively. Adsorption kinetic data were well described by the pseudo-second-order kinetic model. FTIR analyses further indicated that interactions between RB19 and the CS film occurred during adsorption. The CS films also exhibited satisfactory desorption of RB19 at about 80 % after 30 min of desorption at pH 11. Our study demonstrated that the CS films can be easily prepared and applied for effective removal of RB19 in treatment of wastewater.     

Marron farming and environmental sustainability: Western Australia’s case

Despite aquaculture’s contribution providing an additional food source or employment in rural areas, this industry is often presented in a controversial way, including its impact on the environment. However, an argument can also be made in favour of aquaculture operators and their efforts to follow environmentally sound practices. Along these lines, the present study investigates operators’ stance on environmental sustainability from a group of 26 Western Australian marron growers. Overall, the findings demonstrate growers’ commitment to grow marron environmentally, for instance, without the use of fertilisers or feeding. Furthermore, respondents are in agreement with the potential effects of environmentally unfriendly practices, especially as in many cases marron growing is a complement to rural activities such as horticulture and cattle farming. At the other end, some operators voice concerns on a different environmental issue, namely, the challenge that increasing droughts and lack of sufficient rain is posing to their industry.     

Erosional Consequence of Saltcedar Control

Removal of nonnative riparian trees is accelerating to conserve water and improve habitat for native species. Widespread control of dominant species, however, can lead to unintended erosion. Helicopter herbicide application in 2003 along a 12-km reach of the Rio Puerco, New Mexico, eliminated the target invasive species saltcedar (Tamarix spp.), which dominated the floodplain, as well as the native species sandbar willow (Salix exigua Nuttall), which occurred as a fringe along the channel. Herbicide application initiated a natural experiment testing the importance of riparian vegetation for bank stability along this data-rich river. A flood three years later eroded about 680,000 m³ of sediment, increasing mean channel width of the sprayed reach by 84%. Erosion upstream and downstream from the sprayed reach during this flood was inconsequential. Sand eroded from channel banks was transported an average of 5 km downstream and deposited on the floodplain and channel bed. Although vegetation was killed across the floodplain in the sprayed reach, erosion was almost entirely confined to the channel banks. The absence of dense, flexible woody stems on the banks reduced drag on the flow, leading to high shear stress at the toe of the banks, fluvial erosion, bank undercutting, and mass failure. The potential for increased erosion must be included in consideration of phreatophyte control projects.     

A Comparative Approach for Ranking Contaminated Sites Based on the Risk Assessment Paradigm Using Fuzzy PROMETHEE

A ranking system for contaminated sites based on comparative risk methodology using fuzzy Preference Ranking Organization METHod for Enrichment Evaluation (PROMETHEE) was developed in this article. It combines the concepts of fuzzy sets to represent uncertain site information with the PROMETHEE, a subgroup of Multi-Criteria Decision Making (MCDM) methods. Criteria are identified based on a combination of the attributes (toxicity, exposure, and receptors) associated with the potential human health and ecological risks posed by contaminated sites, chemical properties, site geology and hydrogeology and contaminant transport phenomena. Original site data are directly used avoiding the subjective assignment of scores to site attributes. When the input data are numeric and crisp the PROMETHEE method can be used. The Fuzzy PROMETHEE method is preferred when substantial uncertainties and subjectivities exist in site information. The PROMETHEE and fuzzy PROMETHEE methods are both used in this research to compare the sites. The case study shows that this methodology provides reasonable results.     

The Role of Disaggregation of Asset Values in Flood Loss Estimation: A Comparison of Different Modeling Approaches at the Mulde River,Germany

In loss estimation there is a spatial mismatch of hazard data that are commonly modeled on an explicit raster level and exposure data that are often available only for aggregated administrative units. Usually disaggregation methods that use ancillary information to distribute lumped exposure data in a finer spatial resolution help to bridge this gap. However, the actual influence of different mapping techniques and ancillary data on the final loss estimation has not been analyzed yet. In this paper three methods are applied to disaggregate residential building assets using two kinds of land use/land cover (LULC) data. The resulting disaggregated assets are validated and compared using census data of the residential building number on the community and constituency level. In addition, the disaggregated assets are taken to estimate residential building losses due to the flood in August 2002 in 21 municipalities on the River Mulde in Saxony, Germany. Losses are calculated with the help of four loss models. In general, disaggregation helps to decrease the error variance within the loss estimation. It must, however, be stated that the application of sophisticated disaggregation methods does not lead to significant improvements compared to the straightforward binary method. Therefore more effort should instead be put into the provision of high-resolution LULC data. Finally, the remaining uncertainties in loss estimation are high and demand further improvements in all modeling aspects.     

Food decay and offensive odorants: A comparative analysis among three types of food

In this study, a list of offensive odorants including reduced sulfur, carbonyls, nitrogenous, and volatile organic compounds was measured by the indirect (instrumental) method during the decay processes of three food types (snipe egg, mackerel, and squid). The strengths of the odor release were also quantified in terms of dilution-to-threshold (D/T) ratio based on the air dilution sensory test. To collect odor samples for each food type, decaying experiments were conducted in 100 mL throwaway syringes for 1 month. The results showed that ammonia had the largest mean ranging from 385 ppm (fish) to 554 ppm (egg). However, most odorants generally fell in the range of 0.01–10 ppm, regardless of food type. The odor strengths measured with the suprathreshold method in terms of average D/T values increased on the order of 33,520 (egg), 202,330 (fish), and 766,330 (squid). These results were highly comparable to the patterns of odor indices derived by empirical conversion of odorant concentration data. The overall results of this study thus suggest that a unique pattern of odor release develops among different odorants as well as food type.