Titanium dioxide remains one of the most studied semiconductor for photocatalytic applications due to its low cost production, reduced toxicity, ability to break down the organic pollutants and possibility to achieve complete mineralization. In this work, we report on results of the photocatalytic activity of titanium dioxide nanotubes fabricated by electrochemical anodization technique in an electrolyte solution containing a mixture of hydrofluoric acid, ethylene glycol and phosphoric acid. The morphology and crystallinity of the obtained nanotubes were investigated by means of electron microscopy and it was found that nanotubes have a constant outer diameter of 200 nm and an internal conical shape where the diameter gradually decreases from 120 nm at the wide end to 50 nm at the narrow end. The transmission electron microscopy investigation defined two different phases of titanium dioxide obtained after annealing of amorphous TiO2 in air at 650 ?C and 850 ?C. Photocatalytic activity of the samples have been evaluated in methylene blue solution in the presence of dispersed nanotubes under visible and UV irradiation by means of UV/Vis spectroscopy. Anatase phase TiO2 shows the best performance degrading 85 % of dye in 25 min under UV illumination, while rutile phase with anatase inclusions shows the best results with a 50 % decay of dye concentration in 25 min under visible light illumination.

Pattern descriptors invariant to rotation, scaling, and translation represents an important direction in the elaboration of the real time object recognition systems. In this article, the new kinds of object descriptors based on chord transformation are presented. There are described new methods of image presentation - Central and Logarithmic Central Image Chord Transformations (CICT and LCICT). It is shown that the CICToperation makes it possible to achieve invariance to object rotation. In the case of implementation of the LCICT transformation, invariance to changes in the rotation and scale of the object is achieved. The possibilities of implementing the CICTand LCICToperations are discussed. The algorithms of these operations for contour images are presented. The possibilities of integrated implementation of CICT and LCICT operations are considered. A generalized CICT operation for a full (halftone) image is defined. The structures of the coherent optical processors that implement operations of basic and integral image chord transformations are presented.

This paper reports on the influence of the asymmetric gain saturation on the dynamics of InGaAsP Fabry-Perot lasers. The results are obtained by numerical simulations of multimode rate equations. The gain saturation effects that results in competition phenomena among lasing modes are investigated. A hopping multimode case is examined in detail. With means of the bifurcation analysis the regions with instabilities in the evolution of the mode intensities have been found. The following operation in the plane of two parameters are obtained: stable single mode, stable multimode, bistabile, and multimode hopping. The pulse traces of amplitudes of modes are plotted to illustrate the observed behaviors. Finally, the influence of linewidth enhancement Henry factor on the laser behavior is investigated.

The small-to-medium sized Malta International Airport (MIA) is the only airport in Malta, especially in terms of its footprint, and is considered one of the world?s most scenic landings, according to a 2016 poll. The annual passenger turnover is approximately 16 times the country?s population. MIA?s unique features include its proximity to the urban conservation area of Luqa, as well as that town?s other residential and business facilities, and also to the southern coast of Malta and the unique ecological habitats it supports. Its impacts range from noise to atmosphere pollution and, potentially, pollution of the coastal waters, in the eventuality of an air traffic accident. On the basis of the national strategic vision that Malta evolves into an expanding hub in the centre of the Mediterranean, significant investment is earmarked for MIA, including initiatives impacting security, the environment and energy.

The use of coagulation-flocculation process as means of wastewater treatment is gradually becoming more popular. This research work is to evaluate the efficiency of coagulation-flocculation process in the treatment of abattoir effluent. Samples of abattoir effluent were collected from a slaughterhouse at Ede, Nigeria, and Alum was used in the coagulation-flocculation treatment of the effluent. The physico-chemical and bacteriological analyses of the untreated and treated effluent were carried out and these were used in determining the efficiency of the treatment process. The values obtained (from the physico-chemical and bacteriological analyses) were also compared with the effluent standard of Environmental Protection Agency (EPA). Coagulation-flocculation process is performed efficiently in reducing the contaminant level of Colour, TDS, Turbidity, Conductivity, TSS, Total Hardness, COD, Coliform, metals and other pollutants from the effluent.

This paper presents the results of a study of the compressive strength of concrete in a cyclic solar chamber. The analysis of the existing types of industrial solar chambers is carried out and the main structural elements are considered. The method of calculating the solar chamber for the production of concrete products is presented. Experiments were carried out on heavy concrete compositions using MC-Bauchemie superplasticizers additives: MC-PowerFlow 3100 and MC-PowerFlow 2695. The samples were kept in a cyclical solar chamber. The strength of concrete was determined at different periods of concrete hardening. A comparative analysis of the results of the compressive strength of concrete in a solar and normal hardening chamber is carried out.

Evaluation of the building element technical state relies on verification calculations using estimated construction material properties. Physical and mechanical properties are estimated predominately by using non-destructive test methods. The accuracy of these methods is affected by the level of stress-strain state of the structural element and present structural defects. The variability of the concrete properties over time under constant loads is a determining factor for the durability and reliability of the structural element. The influence of the physical and mechanical characteristics of a construction material on the deformation process of the local area of the structural element adjacent to the structural defect has been investigated. The research has been performed on structural models using software systems "LIRA SAPR" and "SOLIDWORKS". A structural model having dimensions of 100 x 100 x 400 mm was used for the study. Materials of concrete grades C12/15 through C25/30 with corresponding properties have been used. Load parameters for modeling of the deformation process varied from 0.1 to 0.5 of the ultimate loads. Performed calculations made it possible to obtain fields of stress, deformation and displacement under different model parameters and stress levels.

Jerusalem artichoke tubers are known for their high content of nutrients, high acidity, pleasant taste and smell and beneficial effects on health. Thus, the capitalization of food products such as bread with Jerusalem artichoke flour, could be an opportunity to diversify the range of new products. The aim of this research was to elucidate the impact of added Jerusalem artichoke flour (in a concentration of 2.5%, 5%, 7.5% and 10%) in wheat flour bread on the sensory and physico-chemical properties of the finished product. Jerusalem artichoke flour has a high dry matter content and a high content of essential amino acids such as histidine, isoleucine, methionine, phenylalanine and valine. In the results we recommend the replacement of wheat flour with 5% Jerusalem artichoke flour, to obtain a product rich in micro and macronutrients with better organoleptic properties and a longer shelf life, which positively influences human health.

In this paper, we investigate the possibility of using the friction method for modifying the microstructure and mechanical properties in the near-surface regions of AISI 316L austenitic steel specimens for the purpose of its practical application. It is shown that a region of severe plastic deformation arises near the friction surface, which transforms the initial fine-grained polycrystalline steel structure into a homogenized zone consisting of a deformed structure with plastic slip bands and weakly pronounced grain boundaries. The change in the microscopic structure results in an increase in this zone of values of micromechanical characteristics, such as microhardness (H), Young's modulus (E), plasticity index (H/E) and resistance index (H3/E2 ). The obtained results are of interest for the potential use of AISI 316L steel in medicine.

Object recognition is of great importance for many civil and military applications and supposes the identification and classification of the object in real-time, regardless of spatial position, angular orientation, etc. In the article, the methods of central and logarithmic central image chord transformations are described. The system for invariant object recognition and space parameters determination was developed based on the proposed image chord transformation operations, which is of a multiprocessor functionally distributed architecture, in which various modules implement separate image processing operations, and allows to recognize the objects regardless of their position, scale, or rotation, and to determine the parameters for targeting The model of a data processing flow in the system was elaborated to permit the determination of the signal processing stages which can be realized in parallel. An analytical estimation and analysis of the system?s data processing time and throughput is carrying out. The approach of the system?s optimization was applied and allows to decrease the total data processing time by 24.5 times and increase the system?s throughput by 75 times.