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Volume 1; Issue 4 (30 December 2017)

Advanced Materials and Technologies Environmental Sciences – AdvMatTechEnv 2017; Vol 1; Issue 4

Bibliographic Data

Abstract

Recently, there have been many studies to decrease environmental pollution around the coal-fired power stations. One of the studies addresses that untreated ash particles cause economic gains for polymer based composites. In this study, free vibration characteristics of bottom ash/epoxy composite beam with respect to 5 and 10% bottom ash additive is considered for possible structural and infrastructural applications. General microstructural methods are handled for bottom ash/epoxy composites, and the modal and stress behaviors of the composites are calculated. Effect of natural frequency on shear stress and Strain energy density at the free edge is examined. Results are given in tabular and graphical forms. Experimental and numerical computations indicate that (i) values of natural frequency of bottom ash/epoxy composites are higher than that of epoxy, (ii) values of damping ratio of bottom ash/epoxy composites are lower than that of epoxy, (iii) shear stress and SED increase with increasing mode number for all bottom ash/epoxy composites.



Volume 1; Issue 3 (30 September 2017) 

Advanced Materials and Technologies Environmental Sciences – AdvMatTechEnv 2017; Vol 1; Issue 3

Bibliographic Data

Abstract

Recently, the introduction of separation membranes is progressing in the field of sewage and industrial wastewater treatment. The treatment methods with membrane separation have many advantages. Firstly, the sedimentation tank has not been required for the sake of gravity sedimentation. It is possible that the reaction tank become compact. Secondly, suspended solids (SS) can be almost completely removed, and it is possible to produce clarified treated water for which even bacteria and viruses can be almost completely removed. For this research, a new and novel separation polytetrafluoroethylene (PTFE) membrane has been produced, and the membrane has been applied to membrane bioreactor and membrane separation coagulation sedimentation treatments on an actual sludge treatment center. The experiment data was obtained through continuous operation during over approximately one year, and did show the similar good performance to a chlorinated polyethylene (CPE) membrane. As a result, the fouling resistance was considerably improved when using the flat PTFE membrane compared to the flat CPE membrane.

Nano-sized CdS has been prepared by aqueous chemical method using glycine as a capping and stabilizing agent. X-ray diffraction (XRD) analysis of as-synthesized material revealed hexagonal wurtzite structure of CdS with average crystallite size 48.1 nm. The observed FTIR spectra support the template role of glycine in controlling the size of CdS nanoparticles. Photo-catalytic efficiency of CdS nanoparticles was investigated under UV irradiation following degradation of methyl orange (MO), as a probe. Effect of some operational parameters such as photo-catalyst load, pH of solution and substrate (MO) initial concentration on the photo-catalytic degradation of the dye have been investigated. Using methyl orange initial concentration 300 mg/L, optimum photo-catalyst load 120 mg /L and pH 4.0, as high as 92 % degradation of methyl orange could be achieved under UV radiation. The photo-catalytic method developed here can be used for large scale treatment of water bodies contaminated with methyl orange dye.

Passive air sampling is a preferred method of air sampling for many applications. Traditionally, this method uses activated carbon as the sorbent and samples are analyzed by chemical or thermal desorption. This research explores the use of carbon nanotubes in the form of a buckypaper as a sorbent for passive sampling by comparing the mass uptake and percent yield to that of the 3M™ Organic Vapor Monitor 3500 over four time trials (30, 60, 120 and 240min) using toluene as the sorbate. A total of 48 samples were taken and results were analyzed using a gas chromatograph. The desorption efficiency and mass uptake rate of the carbon nanotube sorbents were similar to the 3M™ Organic Vapor Monitor 3500. Desorption efficiencies were 85.5 – 100.3% for 3M samplers and 89.5 – 95.5% for carbon nanotube sorbents. The mass of toluene collected at 30-minute and 120-minute time trials showed no significant differences (p = 0.37, 0.1, respectively) while 60min and 240min time trials were significantly different with fabricated sorbents collecting closer to the expected mass (p = 0.02, 0.04 respectively). Overall sampling capacity is lower in the 20mg carbon nanotube buckypapers compared to the 200mg activated carbon pad of the 3M™ OVM 3500 due to somewhat lower adsorption capacity and much lower sorbent mass. While the objective of this study was to explore the suitability of buckypaper sorbents for sampling exposures at low concentration for short durations, a larger mass buckypaper sorbent should provide a similar sampling capacity to standard passive samplers.

The knowledge of moisture transport in porous building materials and components is crucial to predict and avoid several pathologies and is essential to increase the durability. It is easy to know the amount of water that, for example, some material absorbs when in contact with water. However, it is very difficult to determine where the water is, the water transport process, the water movement, etc. Using the gamma ray attenuation technique, it is possible to determine the water content along a building material or component and obtained the water content profile in different moments. So, with this tool, several phenomena can be studied such as: the wetting and drying processes, the thermal performance, waterproof behavior, etc,. This paper presents the gamma ray attenuation technique, the way that the water content profiles can be obtained, some interesting water content profiles obtained for a material, monolithic and multilayered and the discussion of those results.

Volume 1; Issue 2 (30 June 2017)

Advanced Materials and Technologies Environmental Sciences – AdvMatTechEnv 2017; Vol 1; Issue 2

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Abstract

The oxidation of unsymmetrical dimethylhydrazine(UDMH) with different oxidizing agents in atmosphere, water and soil has been reviewed. Emphasis is put on comparison of the oxidative products and the oxidation mechanism in different systems rather than on individual results. The number of the detected oxidative products are more than 30, and major identified products are N-nitrosodimethyamine, Formaldehyde dimethyldrazones, Dimethylamine, Tetramethyl-tetrazene, Formaldehyde, which are proved to have serious environment and human health impact. The main detailed pathway in ozone and oxygen reaction is primary abstracting hydrogen for N-H bond with formation N-amine radical or diazene, followed by add oxygen to form N-oxides radicals; Moreover, the N-oxides radicals undergo disproportion forming NDMA and the diazene leads to dimerization to tetramethyltetrazone, cleavage to dimethylamine; while the hydroxide radical tends to abstract hydrogen from C-H bond leads to formaldehyde and formaldehyde dimethyldrazone. In order to clarify understanding the mechanism, the evaluation of transformation products quantitative analysis, as well as the advancement in theoretical and computational methods is the key role for the further study.

Clustering by fast search and find of density peaks (CFSFDP) is a new density based algorithm that discovers the centers of cluster by finding the density peaks efficiently. CFSFDP is applicable to a lot of clustering problems that deal with static data. Nowadays, more and more data, such as, social networks, blogs, web pages, Internet of things etc., is appearing in dynamic manner. However, CFSFDP is applicable only to organize the static data into different clusters. This paper considers the technique to be used with CFSFDP in the incremental clustering problem. In this paper, a novel approach ICFSFDP based on Nearest Neighbor Assignment (NNA) is proposed. ICFSFDP utilizes the CFSFDP mechanism for clustering the initial dataset and the remaining data-points are assigned to existing clusters based on NNA. Three standard clustering benchmark datasets are used to test the performance of the proposed method. The experimental results present that ICFSFDP based on NNA is efficient and effective to cluster the dynamic data and it is robust to noise as well.

Graphene and its derivatives are extensively used in many applications from medical to environmental or electronic applications, as well. The high interest for this kind of materials is due to the extraordinary electrical and mechanical properties, the good biocompatibility and a remarkable specific surface area. From the point of view of environmental applications, two properties are essential: very high specific surface area (can reach 2600m2/g, twice comparing to Single Wall Carbon Nanotube) and the ability of graphene to be oxidized and thus, the hydrophobic backbone and the hydrophilic moieties can selectively bind the desired hazardous compounds from different media, regardless their hydrophobic or hydrophilic nature. Among the many preparation routes presented in the literature only a few are suitable for obtaining graphene and graphene oxide at reasonable price at large scale. Along with the ability of selectively remove different species, graphene and its derivatives can be used as sensor.

Nd:YAG pulse laser system was used to fabricated TixBi1.7Pb0.3Sr2Ca2Cu3Oy superconductor thin films, were x=0.1, 0.3 and 0.5. All the samples have been annealed after deposition with flow of oxygen for two hours at 800 ºC. X-ray diffraction analysis evidenced that the prepared thin films were consistent of low 2212 and high 2223 phases. Scanning electron microscopy images of the samples revealed that the addition of Ti nanoparticles into (Bi,Pb)-2223 composition would have significant effects on their grain sizes and morphologies. Electrical properties of the thin films can be associated to the modification in the holes content, the highest TC at 114.5 K was obtained for the thin film with x=0.3.

Volume 1; Issue 1 (30 March 2017)

Advanced Materials and Technologies Environmental Sciences – AdvMatTechEnv 2017; Vol 1; Issue 1

Bibliographic Data

Abstract

New mine tailings matrices were formulated from two different mine tailings from Eastern Canada. The tailings were mixed with Portland cement, fly ash, slag and a new binder called Calsifrit. The study consisted of two phases where in the first phase 5 cm3 cubic tailings matrices were formulated to assess the change in curing period on the compressive strength of the matrices. In the second phase of these tests cylindrical specimens were formulated to assess the effect of weathering on the compressive strength of the tailings matrices. The cylindrical specimens were exposed to wetting/drying and freezing/ thawing durability tests before subjecting them to unconfined compression tests. To assess the suitability of such matrices to road construction, their layer coefficients were determined. It was found that the new mine tailings matrices were suitable structurally (even after weathering) for road construction as it was demonstrated by their layer coefficients.

Manganese oxides supported on granular activated carbon (MnOx/GAC) for degradation of UDMH wastewater was prepared via facile in-situ reduction of permanganate by activated carbon. The growth and properties of MnOx/GAC were characterized by scanning electron microscopy, X-ray diffraction, Raman spectra and X-ray photoelectron spectroscopy. Test results showed that MnOx deposited on GAC surface was poorly crystallized layer birnessite-style MnOx and the sample of 30min synthesis time exhibited the best performance on UDMH degradation. Combined with vacuum ultraviolet (VUV), under the best optimal process conditions including 15g/L catalysis dosage, pH 9.0 and 50mg/L initial UDMH concentration, the UDMH and COD removal rate respectively reached 95% and 85% at room temperature.

The cause of the emergence of bio-negative interaction of social and environmental situation in the oil- and gas-field facilities in the Gulf of Guinea (GoG) region has been studied. It has been established that the cause of the negative synergy of socio-ecological situations is due to the imbalance of equipment and building technology, along with increasing social and environmental load on the whole territory, related to the lack of relevant world-class technologies for collection, transportation and recycling of disposals and wastes from staff’s livelihood. It was found that the disorganized placement of oil and gas facilities in a typical area along the coast of the GoG, poor environmental protection, and inadequate organizational and financial mechanisms of the environmental safety are a part of the main factors, which affect the environment. From the analysis of the main factors determining the state of the socio-environmental structures, it follows that the further development of oil- and gas-field facilities cannot be based on pre-existing technologies. New technologies and design solutions for oil- and gas-field facilities that are safe for environment and integrated with nature should be developed and implemented.

Understanding the connection between soil biodegradation and temperature is a matter of concern nowadays. Increasing temperature increases the rate at which soil is degraded by microbial action enhancing carbon losses with a negative impact on the atmosphere and water quality. The number of methods allowing these measurements is small, and additional options that contribute to improve our knowledge about this subject are welcome. Calorimetry is a new alternative to monitor directly and in real time the immediate response of soil microbial activity to changing temperature. This paper shows a methodological application of these calorimetric devices to soil samples with extreme different organic matter properties, to monitor the evolution of their biodegradation rates with increasing temperatures and the fitting of the most widely used models: Q10 and the Arrhenius equation. Results showed that calorimetry is sensitive enough to detect different responses of the soil samples to increasing temperature from 18 ºC to 35 ºC, that the range of temperatures at which the biodegradation rates fitted the existing models varied among soils and that Ea derived from Arrhenius equation was not sensitive in all cases to link soil sensitivity to temperature with the soil organic matter nature.

The paper presents the most important issues relating to the research and application of materials with controlled-release properties that can increase the effectiveness of nutrient uptake, alleviate the negative influence of fertilizers on the environment and reduce labor and energy consumption associated with the use of conventional fertilizers. The article discusses predominantly commercially available controlled-release fertilizers manufactured with the use of sulfur, thermoplastics, polyurethane and alkyd resins. The multistep diffusion model was pointed out as the best tool for the qualitative description and quantitative prediction of the nutrient release. Attention was also paid to the fertilizers prepared with the use of other materials like superabsorbents and polysulfone-based materials. Bio-composites of starch, lignin, cellulose and other natural or synthetic biopolymers were depicted as the most promising materials for the future application. The article contains also the quantitative analysis of bibliographic data and information on the market situation of fertilizers with a delayed nutrient release.