Statistical Behavior of O3, OX,NO, NO2, and NOx in Urban Environment

ABSTRACT

This paper presents the results of the statistical modeling of the ozone concentration in Campo Grande, Brazil in 2016. Five sets of data, summer (January–March), autumn (April–June), winter (July–September), spring (October–December), and all year round were used. The results show that the maximum concentrations of oxidants occur at 3:00 p.m., the diurnal NO variation, the concentrations show a cycle with two peaks at 7:00 and the other at 11:00 p.m. It has been found that the best distribution for the five datasets is the lognormal distribution of three parameters. The seasonality of the datasets shows greater asymmetry during the summer, due to the greater tail distribution, mainly due to the greater photochemical activity.     

Metals (major,essential to non-essential) composition of the different tissues of three demersal fish species from İskenderun Bay,Turkey

This study was performed to investigate certain major and toxic metal concentrations in different tissues of three demersal fish species (Triglia lucerna, Lophius budegassa, Solea lascaris). Generally, skin and liver exhibited higher metal concentrations than did muscle. Sodium and arsenic concentrations were found at higher levels in muscle tissues than in livers and skin, while zinc and nickel in different organs were classified as follows: skin > liver > muscle tissues. The concentrations of trace metals in fish samples indicated that S. lascaris was more contaminated than were other fish species, followed by L. budegassa and T. lucerna. It may be concluded that consumption of these species from this region is not likely to pose a threat for human health. However, although the concentrations are below the limit values for fish muscles, a potential danger may emerge in the future, depending on domestic waste waters and industrial activities in the region. Therefore, further monitoring programmes should be conducted.     

A novel co-processing method to manufacture an API for extended release formulation via formation of agglomerates of active ingredient and hydroxypropyl methylcellulose during crystallization

A novel process for generating agglomerates of active pharmaceutical ingredient (API) and polymer by swelling the polymer in a water/organic mixture has been developed to address formulation issues resulting from a water sensitive, high drug load API with poor powder properties. Initially, the API is dissolved in water, following which hydroxypropyl methylcellulose (HPMC) is added, resulting in the imbibing of water, along with the dissolved API, into the HPMC matrix. The addition of acetone and isopropyl acetate (anti-solvents) then causes the API to crystallize inside and on the surface of HPMC agglomerates. The process was scaled up to 20?kg scale. The agglomerates of API and HPMC generated by this process are ～350?µm diameter, robust, and have significantly better flow than the API as measured by Erweka flow testing. These agglomerates exhibit improved bulk density, acceptable chemical stability, and high compressibility. The agglomerates process well through roller compaction and tableting, with no flow or sticking issues. This process is potentially adaptable to other APIs with similar attributes.     

Development of constant output–input force ratio in slider–crank mechanisms

In the slider–crank mechanism whereby output piston force is produced against an input force at crank pin centre, the output force varies rapidly when the crank changes its position. For the applications that require a constant piston pushing force as in feeder mechanisms, a method is needed for identifying the parameters to keep output force at a constant value for any crank angle position. Hence in this study, two methods are shown for a slider–crank mechanism operating in horizontal plane. In the first one, a manual control process to generate a constant piston force and the resulting errors are demonstrated. In the second one, identifying the parameters of a mechanical controller for a readily available slider–crank mechanism in an open force control process and the associated error state are shown. Then, an approach to optimize the results of open force control is explained. Finally, the developed methods are generalized for any orientation of the whole slider–crank mechanism. A user friendly interface is developed to transform all the processes into a computer programme. The effectiveness of the methods are numerically illustrated on examples. The results of these examples show that ±4% deviation from the required output force can be obtained pending on the user’s ability while the optimized open force control process provides a maximum error of ±0.4% without any user intervention during operation.     

Anomalous charge transport in multiple interconnected polyaniline nanofibers

We report the unusual charge transport phenomena in polyaniline nanofiber networks and its dependencies on temperature, applied magnetic and electric field, and on the type of fiber morphology. The conductivity of nanofiber networks follows quasi 1-D variable range hopping (VRH) and demonstrates a peak at ～240 K in samples with high density of interfiber intersections. This anomalous peak of conductivity is attributed to change in the interfiber contact resistance with temperature. In all polyaniline nanofiber networks, positive and negative magnetoresistances (MRs) are observed and accounted for by shrinkage of localized electron wavefunctions and suppression of quantum interference among possible tunneling paths by magnetic field. We found that the magnitude of both positive and negative MR gets smaller with decreasing density of interfiber intersections and can be explained by decreasing of hopping barriers as well as decreasing of number of current pathways within VRH network. We also detected that the magnitude of MR in polyaniline nanofiber networks is affected by the applied electric field which we propose is due to field-induced suppression of the hopping activation energies.     

Evaluation of the Design, Planning, Construction Phases, and Structural Content of Permanent Residential Dwellings Built after the 1999 Eastern Marmara Earthquakes in Turkey

The aim of this study is to survey and evaluate permanent housing structures built after the Marmara earthquakes based on the principles of earthquake resistant design of reinforced concrete structures. The seismicity of Turkey requires immediate attention as there is a high probability of another major earthquake event in the next 30?years in Istanbul. The classification of structural systems, the damage patterns and behaviors of structural systems, and structural and nonstructural components under lateral earthquake loads, are analyzed. Based on this analysis, reliable structures can be built without overextending the Turkish economy, and loss of life and structural damage can be reduced by designing structures with greater earthquake energy dissipation capacity. The selection of project areas and the strength of the structural system are thoroughly analyzed taking postearthquake public psychology into account. Structural characteristics of permanent housing built subsequent to the Marmara earthquakes are critiqued and documented with a case study.     

A Kinetic Model for Dissolution of Zinc Oxide Powder Obtained from Waste Alkaline Batteries in Sodium Hydroxide Solutions

Metallurgical and Materials Transactions B - The determination of individual dissolution behaviors of zinc and manganese in waste alkaline battery powders is an important subject from the points of...     

Effects of Supercritical Fluid Extraction Parameters on Unsaturated Fatty Acid Yields of Pistacia terebinthus Berries

Utilization of renewable resources and development of new processes aimed at converting these materials into value added bio-products are gaining more emphasis. The scope of this study was to optimize supercritical CO₂ extraction (SFE) parameters such as pressure, temperature and flow rate for the yields of unsaturated fatty acids from Pistacia terebinthus berries by a Box-Behnken statistical design. All samples were analyzed for fatty acids by GC-FID. The most effective variables were pressure (P < 0.005) and flow rate (P ≤ 0.005). Maximizing the evaluative criteria for dependent variables (oleic acid, linoleic acid and linolenic acid), optimal conditions were determined to be 240 bar, 60 °C and a flow rate of 16 g/min yielding 51.2% oleic acid, 26.5% linoleic acid and 1.0% linolenic acid. The amounts of unsaturated fatty acids in SFE samples (81.3%) were higher than the hexane (74.3%) and were similar to that of cold press samples (80.1%). High concentrations of unsaturated fatty acids can indicate the utilization of the berries as a major dietary source and demonstrate challenges for industrial application of SFE as a green technology.     

Biodegradable Implantable Sensors: Materials Design,Fabrication, and Applications

The ability to monitor diseases, therapies, and their effects on the body is a critical component of modern care and personalized medicine. Real time monitoring can be achieved by analyzing body fluids or by applying sensors on, or alternatively, inside the body. Implantable sensors, however, must be removed. Second removal procedures lead to further tissue damage, which can be a problem in tissues such as those of the central nervous system. The use of biodegradable sensors alleviates these problems since they do not require removal procedures. Recent advances in material science made it possible for all sensor components to be biodegradable. Small size and power of implants, and the limited selection of materials are the main constraints determining the capabilities of the biodegradable device. Thus, the design will be always a challenge exploring a trade-off among these parameters. Despite of the encouraging results illustrating that biodegradable sensors can be as accurate and reliable as commercially available nondegradable ones, biodegradable implantable sensors are still in their infancy. Significant advances made in this area are critically reviewed in this paper, and future prospects are highlighted.