bluuebunny/crossref_metadata_2025 huggingface dataset:
Surfactants: Pharmaceutical and Medicinal Aspects
Authors:   PCTE Institute of Pharmacy, PCTE Group of Institutes, Ludhiana, Punjab, INDIA, Sekhon Bhupinder Singh
Published: April 2015

Surfactants are amphipathic substances with lyophobic and lyophilic groups and are critical components in pharmaceutical products. Surfactants have several uses in pharmaceuticals, i) for solubilisation of hydrophobic drugs in aqueous media, ii) as components of emulsions ,iii) surfactant self-assembly vehicles for oral and transdermal drug delivery, iv) as plasticizers in semisolid delivery systems, and v) as agents to improve drug absorption and penetration. Non-ionic surfactants such as ethers of fatty alcohols are most commonly used in pharmaceuticals. Cationic surfactants are capable of exerting antibacterial properties by disrupting bacterial cell membranes. In pharmaceutical processing, phospholipid lecithin, bile salts, certain fatty acids and their derivatives have become indispensable since they afford a uniquely effective and eficient mechanism of drug carriage by solubilising the drugs of fatty origin. The antibacterial, antifungal and antiviral activities make biosurfactants relevant molecules for applications in combating many diseases and as therapeutic agents. Biosurfactants have the potential for use as major immunomodulatory molecules, as anti-adhesive biological coating for biomaterials, in vaccines and gene therapy, and they may be incorporated into probiotic preparations to combat urogenetical tract infections and pulmonary immunotherapy. Gemini surfactants are effective potential transfection agents for non-viral gene therapy. Ionic liquids act as secondary surfactants and the use of surfactant/ionic liquid systems should be explored to build speciic properties in the organized medium, and to explore pharmaceutical applications of traditional, biosurfactant and Gemini surfactants.
An Ethanol-Based Proliposome Technology for Enhanced Delivery and Improved “Respirability” of Antiasthma Aerosols Generated Using a Micropump Vibrating-Mesh Nebulizer
Authors:   Institute of Nanotechnology and Bioengineering, 2 School of Pharmacy and Biomedical Sciences, University of Central Lancashire, Preston PR1 2HE, England, United Kingdom, Elhissi Abdelbary M.A. , Brar Jasmeet ,   Department of Pharmaceutics, UCL School of Pharmacy, 29-39 Brunswick Square, London WC1N 1AX, England, United Kingdom, Najlah Mohammad ,   Faculty of Pharmacy, Albaath University, Homs, Syrian Arab Republic, Roberts Simon A. ,   Department of Pharmaceutics, UCL School of Pharmacy, 29-39 Brunswick Square, London WC1N 1AX, England, United Kingdom, Faheem Ahmed ,   School of Pharmacy and Pharmaceutical Sciences, University of Ulster, Coleraine BT52 1SA, Northern Ireland, UK, Taylor Kevin M.G. ,   Department of Pharmaceutics, UCL School of Pharmacy, 29-39 Brunswick Square, London WC1N 1AX, England, United Kingdom
Published: April 2015

Salbutamol sulphate liposomes were generated using ethanolbased proliposomes followed by nebulization using an Aeroneb Pro vibrating-mesh nebulizer. The droplet size, output and fine particle fraction (FPF) of the drug incorporated in liposome formulation were compared to those of a conventional drug solution. Aerosol output was determined gravimetrically and drug output was analyzed by using high performance liquid chromatography. The potential of aerosol deposition in deep lung was evaluated using inertial impaction and laser diffraction. The effect of formulation surface tension on the aerosol performance was studied. Output and FPF were improved using liposomes compared to the conventional solution, for instance, FPF values were 57.85% and 45.81% respectively. The volume median diameter as measured by laser diffraction was respectively 3.44 Î¼m and 3.22 Î¼m; however, the higher FPF of the liposome formulation is justified by the lower polydispersity of its aerosol. The improved aerosol performance using liposomes was attributed to the reduction of surface tension caused by the presence of phospholipid. This is the first study that demons trates the ability of liposomes to improve the nebulized drug output and FPF.
Receptor Identification: Advances in Ligands and Transmitters Discovery
Authors:   Chitkara College of Pharmacy, Chitkara University, Rajpura, Punjab-140401, Arora Sandeep , Raghavan Govindrajan ,   Dabur International, Dubai, Kumar Avaneesh ,   Chitkara College of Pharmacy, Chitkara University, Rajpura, Punjab-140401
Published: April 2015

Receptor identification is an integral part of drug discovery and development. By the beginning of the next millennium, the search for the natural ligands of the orphan G-protein-coupled receptors will lead to the discovery of so many new peptides that it may well double their present number. It has recently become evident that all types of chemical messengers, hormones and transmitters act through membrane receptors which constitute our largest superfamily of proteins, i.e. the G protein-coupled receptors. The development of targeted therapies has revolutionized the treatment of various chronic diseases. Receptors have well-conserved regions that are recognized and activated by hormones and neurotransmitters. These ligands are peptides, lipids or biogenic amines, and act as transmitter molecules. Identification of orphan receptors include screening, binding and reverse engineering that help to find out cysteinyl leukotriene CysLT1 and Cys T2, hepatointestinal leukotriene B4, motilin, Ghrelin, Growth hormone-releasing peptide and growth hormone secretagogue receptor and many more. Techniques involved in screening of receptors include low stringency hybridization followed by PCR-derived approaches helps to discover various orphan g protein couple recptors (oGPCR). The discovery of the oGPCR represents a hallmark in neuroscience research, and the exploitation of its numerous physiological and pathophysiological functions is a promising avenue for therapeutic applications.
Estimation of Total Phenols and Flavonoids in Selected Indian Traditional Plants
Authors:   Department of Pharmaceutical Sciences and Drug Research, Punjabi University, Patiala-147 002, Punjab, India, Kumar Deepak , Jamwal Anupam ,   Department of Pharmaceutical Sciences and Drug Research, Punjabi University, Patiala-147 002, Punjab, India, Madaan Reecha ,   Chitkara College of Pharmacy, Chitkara University, Rajpura, Punjab-140401, Kumar Suresh ,   Department of Pharmaceutical Sciences and Drug Research, Punjabi University, Patiala-147 002, Punjab, India
Published: April 2015

Traditionally, aerial parts of Abies pindrow Royle (Himalayan Fir; Pinaceae); Abies webbiana Lindl. (Talispatra; Pinaceae); Cephalandra indica Naud. (Ivy Gourd; Cucurbitaceae) and roots of Calotropis gigantea (L.) Dryand (Giant Milkweed; Asclepiadaceae) have been used in the Indian systems of medicine for the treatment of various ailments. But no systematic phytochemical work has ever been carried out on these potential plants. Thus, it was planned to estimate total phenols and flavonoids content in methanol extract, ethyl acetate fraction (EAF) and remaining methanol extract (RME) of selected plants. Properly identified plants were defatted with petroleum ether, and then separately extracted in a Soxhlet apparatus with methanol. The methanol extract of each plant was partitioned by ethyl acetate solvent to obtain EAF of respective plant. The total phenols and flavonoids contents were estimated using standardized procedures. Quantitative determination of total phenols and total flavonoids was done using standard curve of gallic acid (linearity: 20 to 120 mg/ml; r2 = 0.995) and quercetin (linearity: 30 to 180 mg/ml; r2 = 0.997), respectively. EAF of selected plants contained higher content of phenols and flavonoids, where as lowest content was observed in RME of plants. The content of total phenols and flavonoids in selected plants were found to be in order of C. indica > A. webbiana > A. pindrow > C. gigantea. The available literature reveals that polyphenols have been reported to possess varied pharmacological activities. As selected Indian plants contain polyphenols as major class of phytoconstituents, it is suggested that these constituents may be responsible for their medicinal uses.
Resveratrol: Biological Activities and Therapeutic Potential
Authors:   Department of Biotechnology, Thapar University, Patiala, Punjab, India, Saxena Sanjai , Srivastava Anugya ,   Department of Biotechnology, Thapar University, Patiala, Punjab, India
Published: April 2015

Resveratrol is a polyphenolic flavonoid initially identified as a phytoalexin and as a major constituent of red wine. However interest in this molecule initially developed as a cardioprotective agent and in due course of time therapeutic actions came into limelight. This article explores the different therapeutic activities of Resveratrol and highlights their possible mode of action responsible for its therapeutic action. It becomes evident from this article that Resveratrol has a pharmacological agent that has widespread targets and therefore due emphasis on specific biological action need to be addressed using medicinal chemistry and quantitative structure activity relationships in developing new congeners of Resveratrol to be exploited as drugs.
Development And Characterization of Inhaled Chitosan Nanoparticles Loaded with Isoniazid
Authors:   Research scholar, Karpagam university, Coimbatore, Tamilnadu, India, V JuNIse , saRaswaThI R ,   Professor in Pharmaceutics, Jazanuniversity, Jazan, Kingdom of saudi arabia
Published: April 2015

The objective of our study is to load first line anti-tubercular drug, Isoniazid in chitosan Nanoparticles in order to enhance bioavailability and to reduce dose frequency. The chitosan nanoparticles containing the drug Isoniazid were prepared by the method of spontaneous emulsification. Chitosan gel containing drug is cross linked with Glutaraldehyde and nanoparticle suspension obtained was centrifuged at 5000 rpm. It was then evaluated for Drug loading, swelling index, Mucoadhesive force, Zeta potential, DLS studies, DSC studies, SEM studies, In vitro Drug release, Pharmacokinetic Studies and Stability studies.Formulation 1(F1) shows maximum Drug Loading, Swelling index and mucoadhesive force. The positive zeta value was obtained for all formulations due to positive charge of polymer used in preparation of dispersion. The DLS plot of Formulations shows that Average particle diameter are in the range of 661.8-823.8nm. The SEM study revealed that the micrographs of cross linked chitosan nanoparticles have smooth surface. The thermogram of the formulations showed the shifting of endotherm. This indicates the possible change in the release kinetics and bioavailability of the drug. In vitro drug releases was found to be maximum for formulation F6. Pharmacokinetic evaluation shows all the formulation shows first order rate release profile and release mechanism from nanoparticles is diffusion controlled. Stability studies indicated that the developed chitosan nanoparticles are physically and chemically stable and retain their pharmaceutical properties at various environmental conditions over a period of 3 months.
Panoramic View on Quality by Design
Authors:   Department of Pharmaceutical Sciences, Maharshi Dayanand University, Rohtak-124001, India, Tripathy Swagat ,   Apotex Research Private Limited, Banglore – 560 099, India, Dureja Harish ,   Department of Pharmaceutical Sciences, Maharshi Dayanand University, Rohtak-124001, India
Published: April 2015

Quality by design (QbD) is an essential tool in pharmaceutical environment for having product/process/method impregnated with quality. Now, QbD is the greatest solution to construct quality in all pharmaceutical products, while in the same time making it as a part of system is also a key challenge for Industry. For understanding of QbD, it is very much essential to understand the desire product performance profile [Target product Profile (TPP), Target Product Quality Profile (TPQP)] and identify critical quality attributed (CQA). Basically, for meeting the product attributes, the product formulation and process can be designed on the basis of these stated parameters. Nonetheless, this helps in recognizing the effect of raw materials, critical material attributes (CMA), critical process parameters (CPP) on the CQAs and identification and control sources of variability. The in and out understanding for QbD in generic pharmaceutical industry is really vital, because now and then FDA is taking firm stand to make mandatory “deadline” for inclusion of QbD. Therefore, an attempt has been made to highlight quality by design for generic drugs and its implications to pharmaceutical industry.
¿Qué ocurre con el banco de semillas del suelo 17 años después del corte de la vegetación?
Authors: Brasil Mendes Leonardo , Andrade da Silva Kleber , Melo dos Santos Danielle , Falcão Fraga dos Santos Josiene Maria , De Albuquerque Ulysses Paulino , De Lima Araújo Elcida
Published: April 2015

Seed banks play an important role in the resilience of potential anthropogenic areas and are influenced by seasonal variation. The spatial and temporal heterogeneity of the forests influences the richness and density of the soil seed bank, but there is a hypothesis that such influence can be changed in anthropogenic areas, where we expect to find lower richness and seed density in relation to the seed bank of mature forests. The richness and seasonal density of seeds in the soil depth of a young caatinga forest, 17 years after an agricultural activity was abandoned, were evaluated and compared with those of a mature forest. The study was conducted at the Instituto Agronômico de Pernambuco - IPA (Estação Experimental José Nilson de Melo), located in Caruaru, Pernambuco, Brazil, in an area of tropical dry forest, known locally as “caatinga”. The local climate is seasonal, the dry season occurring from September to February and the rainy season concentrated in the remaining months. The average annual rainfall over time (time series of 30 years) is 692mm. In each climatic season (rainy and dry), the seed bank was sampled in 210 20x20cm plots (105 in the leaf litter and 105 at 5cm soil depth). The richness and seed density of the soil samples were evaluated by the method of seedling emergence. The seed bank had 47 species, with a predominance of herbaceous plants. Seasonal variation in richness and seed density in the soil (leaf litter + soil) was not significant, but 42 species of the mature forest were absent from the seed bank of the young forest, despite 17 years of natural regeneration and its proximity to the mature forest. On its own, the soil has greater richness and density of seeds than the leaf litter. The depth of seed deposition in the soil bank of the young forest significantly explained 36% of the species richness and 16% of the seed density, with a significant interaction effect with the climatic season only on species richness, explaining 4% of the variation recorded. The seed density of the young forest (1 277seeds/m2) was greater than that the mature forest indicating that the time abandoned had not yet been sufficient for complete recovery of plant diversity and there is no longer any seed limitation of pioneer species for regeneration of the young forest.
Efecto de la espirulina (Arthrospira platensis) (Oscillatoriales: Cyanobacteria) en la cría experimental de Pseudosuccinea columella (Basommatophora: Lymnaeidae)
Authors: Prepelitchi Lucila , Pujadas Julieta M. , Wisnivesky-Colli Cristina
Published: April 2015

Snails of the family Lymnaeidae, as Pseudosuccinea columella, are the intermediate hosts of Fasciola hepatica, the causative agent of fasciolosis in human and livestock all over the world. A thorough knowledge of snail biology is essential for describing the transmission dynamics and for controlling this disease. Since food quality has had a significant effect on snail growth, fecundity and fertility, in this study we evaluated the use of spirulina (Arthrospira platensis) as a food resource for the artificial breeding of P. columella, an invasive snail and the main intermediate host of F. hepatica in Northeastern Argentina. The main purpose was to measure the effect of spirulina on fitness parameters such as survival rate, growth rate, size at first reproduction, lifetime fecundity and viable offspring. A total of 20 676 newly-laid F2 eggs were used; half of them were fed with lettuce (treatment L) and the other half with lettuce plus spirulina (treatment L+S). In comparison with P. columella snails fed only with lettuce, we found that P. columella fed with lettuce plus spirulina: 1) showed higher survival rates, 2) grew faster and showed higher growth increments, 3) attained sexual maturity earlier in time (L+S:60 days vs. L:120 days) and at a smaller size (L+S:4.8mm vs. L:8.2mm), 4) had a longer reproductive period (L+S:150 days vs. L:90 days), 5) produced a higher number of eggs/snail (L+S:29.6 vs. L:13.3), and 6) showed a higher offspring hatching rate (L+S:70% vs. L:40%). The supplementation of P. columella diet with commercial spirulina enhances it fitness and improved the artificial breeding of this species. Spirulina may have a direct positive effect on P. columella development by consuming it, along with an indirect positive effect by improving the water quality. This rearing technique provided large number of reproducing adults and a continuous production of offspring, which are essential for developing future experimental studies in order to improve our knowledge on P. columella biology.
Evaluación de fenoles y limonoides en hojas de Cedrela odorata (Meliaceae) de una plantación experimental establecida en Tezonapa Veracruz, México
Authors: Mariscal-Lucero Samantha Del Rocío , Rosales-Castro Martha , Sánchez-Monsalvo Vicente , Honorato-Salazar José Amador
Published: April 2015

Cedrela odorata (Meliaceae) is a native timber tree to Tropical America, known for its high-quality wood, unfortunately, plantations of this species are severely attacked by Hypsipyla grandella. The attraction or repellency of this pest is related to secondary metabolites such as phenols and limonoids (triterpenes); therefore, it is important to study these compounds to understand the phytochemical phenomena behind this problem.  With this aim, the concentration of total phenols and limonoides was evaluated in C. odorata leaves from a plantation established in Tezonapa Veracruz, Mexico. For this, a total of 66 tree leaves samples, from seven sites, were analyzed. Phenols and limonoids concentration showed significant differences not only among different provenances, but also among individual trees of the same site (Tukey, p≤0.05). Phenols concentration was variable and in the range from 49 to 223mg EAG/g e for total phenols, from 7 to 158mg EC/g e for flavonoids and from 4 to 104mg EC/g e for proanthocyanidins. Limonoids concentration was also variable, ranging between 227 and 748mg EL/g e. A major compound was found by High-Performance Liquid Chromatography with Ultraviolet Diode Array Detection (HPLC-UV-DAD), which corresponded to a flavonol kaempferol glycoside derivative; additionally, a flavanol catechin was also detected at low concentrations. GC–MS allowed the identification of the sesquiterpenoids β-elemene, E-caryophyllene, aromadendrene, α-humulene, γ-cadinene, D-germacrene, bicyclogermacrene, and the poly terpenoids D-α-tocopherol and β-sitosterol. Our results suggest that the evaluation of phenols may play an important role as a selection parameter for improvement and conservation programs, if they are complemented with conventional breeding practices.
Estructura de la población del cangrejo rojo de manglar, Goniopsis cruentata (Decapoda: Grapsidae) bajo diferentes impactos de pesca: Implicaciones para la gestión de los recursos.
Authors: Hirose Gustavo L. , Souza Laize S. , Silva Sonja L. R. , Alves Douglas F. R. , Negreiros-Fransozo Maria Lucia
Published: April 2015

The red mangrove crab, Goniopsis cruentata, influences the recruitment and composition of plant species in the mangrove ecosystem and it is an important fishery resource. Nevertheless, no current management and conservation plans are available for this species for the Brazilian coast. This investigation evaluated the population structure and reproductive biology in populations of G. cruentata under contrasting fishery pressures. The sampling program was carried out in two mangroves, Vaza-Barris and Sergipe River, from January through December 2011. Crabs from both mangroves were randomly collected by a professional fisherman during daytime low tide periods, using a fishing rod baited with pieces of a locally abundant gastropod, Pugilina morio, during 20min/area (catch per unit effort). Monthly measurements of air, sediment surface layer and water temperatures were obtained with a digital thermometer and salinity with an optical refractometer. Both crab populations were compared concerning their abundance, body size, sex ratio, size at onset of sexual maturity and fecundity (FI). Abiotic factors (air, water and mud temperature; and salinity) showed no significant differences between sampling localities. A total of 4 370 crabs were sampled, 2 829 from the Sergipe River and 1 541 from the Vaza-Barris River. The abundance and body size of crabs were compared between mangroves, and statistically significant differences were found. The sex ratio for both populations differed from the expected 1:1 ratio, and a significant deviation in favor of juvenile males was obtained, while adults showed a bias toward females. The estimated size at onset of sexual maturity for both sexes was similar in both populations. However, the populations differed significantly in the number and volume of eggs: a higher FI was obtained in females from the Sergipe River, while a higher egg volume was observed in females from the Vaza-Barris River mangrove. These results indicated a tendency to decrease the body size, the abundance of crabs and the reproductive potential of the species, with higher fishing intensities, reinforcing the need to develop a management plan as well as to establish conservation units for G. cruentata in the Northeastern Brazilian coast. Habitat loss in conjunction with long-term overfishing can have irreversible consequences, which can impact not only the populations of commercially exploited crabs, but the dynamics of virtually the entire mangrove ecosystem.
In-Situ High Temperature XRD on U0.54Pu0.46O2-x A Study of the Miscibility Gap
Authors: Strach Michal , Belin Renaud C. , Richaud Jean-Christophe , Rogez Jacques
Published: April 2015

It has been shown in previous studies that a miscibility gap exists in the hypo-stoichiometric region UO2-PuO2-Pu2O3 with one phase poor in oxygen, and the other with an O/M (Oxygen to Metal ratio) close to 2.00. Data on the evolution of this region in temperature, especially in the vicinity of the oxygen content corresponding to the highest temperature at which the gap can be observed, is scarce. A high temperature X-ray diffractometer with a dedicated gas control setup was used to study the described region in-situ. We have observed reflections of the two cubic phases, with one increasing and the other decreasing in intensity during the thermal plateaus lasting up to 20 h. We compare the calculated lattice parameters with literature. We estimated the O/M evolution of our samples from a comparison of phase fractions values obtained by Rietveld refinement and calculations using the Calphad method.
Reliability of fuzzy systems evaluation methodology using different types of vague sets
Authors: A. A. Kosolapov
Published: April 2015

Purpose. Development of the reliability calculating methodology of fuzzy systems with components, reliability parameters of which are described by the membership functions of various kinds. Methodology. Systematic analysis of the known approaches to the assessment of the reliability of fuzzy systems with vague boundaries and different kinds of membership functions. Findings. A unified description and the new tabular algorithm of various arithmetic operations run between the various types of fuzzy sets are proposed and tabular methods of reliability analysis of the basic structures of fuzzy systems are developed. Originality. A generalized description of triangular and trapezoid-shaped accessory functions of fuzzy boundaries in a special tuples is introduced, analytical expressions for the formation of tabular schedules of their functions and the calculation of the reliability of fuzzy systems with complex structures are obtained: sequential, redundant - parallel, serial-parallel, parallel-serial. The practical value.The obtained models and tabular algorithms simplify the calculations of the reliability of complex electro-mechanical human-machine automation systems with fuzzy parameters and vague boundaries.
Method of construction spatial transition curve
Authors: Ustenko S. A. , Didanov S. V.
Published: April 2015

Purpose. The movement of rail transport (speed rolling stock, traffic safety, etc.) is largely dependent on the quality of the track. In this case, a special role is the transition curve, which ensures smooth insertion of the transition from linear to circular section of road. The article deals with modeling of spatial transition curve based on the parabolic distribution of the curvature and torsion. This is a continuation of research conducted by the authors regarding the spatial modeling of curved contours. Methodology. Construction of the spatial transition curve is numerical methods for solving nonlinear integral equations, where the initial data are taken coordinate the starting and ending points of the curve of the future, and the inclination of the tangent and the deviation of the curve from the tangent plane at these points. System solutions for the numerical method are the partial derivatives of the equations of the unknown parameters of the law of change of torsion and length of the transition curve. Findings. The parametric equations of the spatial transition curve are calculated by finding the unknown coefficients of the parabolic distribution of the curvature and torsion, as well as the spatial length of the transition curve. Originality. A method for constructing the spatial transition curve is devised, and based on this software geometric modeling spatial transition curves of railway track with specified deviations of the curve from the tangent plane. Practical value. The resulting curve can be applied in any sector of the economy, where it is necessary to ensure a smooth transition from linear to circular section of the curved space bypass. An example is the transition curve in the construction of the railway line, road, pipe, profile, flat section of the working blades of the turbine and compressor, the ship, plane, car, etc.
Research of mechanical characteristics of pb-ca-sn alloys and tapes for cur-rent leads in sealed lead-acid batteries (Vrla)
Authors: Kazacha Yu. I. , Shnurovoy S. V. , Ivanov V. A. , Dzenzerskiy V. A. , Burylov S. V. , Skosar V. Yu.
Published: April 2015

Purpose. The modern trend in lead-acid battery industry is the changeover to reliable and safe leak-proof VRLA batteries. However, the properties of grid alloys of these batteries are still insufficiently studied, that hampers application of these batteries at railway transport. The purpose of this work is the research of dependence of mechanical properties of grid alloys on temperature conditions of casting, deformation of rolling and ageing time. Methodology. Mechanical properties of alloys and grids have been defined at standard tensile testing machine R-0,5. Findings. The rolling of lead-calcium alloys with deformation more than 90% raises their durability and reduces their plasticity. When rising the temperature of the casting moulds (in range 60-170°С) the durability of lead-calcium and lead-antimony alloys decreases, and the plasticity increases, that are mostly evident for PbCa0.1Sn0.3 alloy, and least of all – for PbCa0.05Sn1.1 alloy. Durability of lead-calcium and lead-antimony alloys increases and plasticity decreases with increasing the time of ageing: this is mostly evident for alloy PbCa0.05 Sn1.1 and strips made from it. Originality. It was determined that decrease of alloys overcooling at crystallization results in drop of their durability and increase of plasticity. The composition and structure of alloys strongly influence dynamics of their ageing. Practical value. It is proposed by authors: a) to increase the temperature of crystallization of alloy for negative grid strip to 120-160°С instead of 80-120°С, that will raise plasticity of strip and reduce deterioration of the equipment; b) to replace PbSb1.8Se alloy of cast grids by PbCa0.1Sn0.3 alloy, that will allow reducing weight of grids by 25 % at the same durability; c) to increase range of ageing of grids cast from PbCa0.1Sn0.3 alloy to 3-30 days that reduces the production costs. It’s all taken together will reduce deterioration of the process equipment and cut down production cost at conservation of characteristics of production.
Elucidation of mechanism wear carbon steel with structure of martensite
Authors: Vakulenko I. A.
Published: April 2015

Purpose. The purpose of the paper is an estimation of degree of metal hardness change for the railway wheel with martensite structure during rolling. Methodology. As strength characteristic the Rockwell hardness is used. Wear tests were conducted in the conditions of normal loading with (10%) and without sliding on the test equipment SMTs-2. Parameters of the fine crystalline structure (tetragonality degree of the crystalline grid, dislocation density, scale of coherent scattering regions, and disturbance value of the crystalline grid of second kind) are determined by the methods of X-ray structural analysis. Findings. During operation of the railway wheels with different strength level, origin of defects on the wheel thread is caused by simultaneous action of both the friction forces and the cyclically changing loadings. Considering that formation of damage centers is largely determined by the state of metal volumes near the wheel thread, one should expect the differences in friction processes development at high contact stress for the wheels with different strength level and structural state. Originality. During the wear tests softening effect of carbon steel with martensite quenching structure is obtained. Softening effect equaled 3.5–7% from the level of quenched metal hardness. The softening effect is accompanied by the reduction of tetragonality degree of the crystalline structure of martensite, reduction of coherent scattering regions, dislocation density increase and crystalline grid disturbance of the second kind. Practical value. The results point out the necessity for further studies to clarify the resulted softening effect mechanism.
Adhesion strength of nickel and zinc coatings with copper base electroplated in conditions of external stimulation by laser irradiance
Authors: Dudkina V. V.
Published: April 2015

Purpose. The investigation of laser irradiance influence on the adhesion strength of nickel and zinc coatings with copper base and the research of initial stages of crystallization for nickel and zinc films. Methodology. Electrodeposition of nickel and zinc films from the standard sulphate electrolyte solutions was carried out on the laser-electrolytic installations, built on the basis of gas discharge CO2-laser and solid ruby laser KVANT-12. The adhesion strength of metal coatings with copper base are defined not only qualitatively using the method of meshing and by means of multiple bending, but also quantitatively by means of indention of diamond pyramid into the border line between coating and base of the side section. Spectrum microanalysis of the element composition of the border line “film and base” is carried out using the electronic microscope REMMA-102-02. Findings. Laser irradiance application of the cathode region in the process of electroplating of metal coatings enables the adhesion strength improvement of coating with the base. Experimental results of adhesive strength of the films and the spectrum analysis of the element composition for the border line between film and base showed that during laser-assisted electroplating the diffusion interaction between coating elements and the base metal surface takes place. As a result of this interaction the coating metal diffuses into the base metal, forming transition diffused layer, which enhances the improvement of adhesion strength of the coatings with the base. Originality. It is found out that ion energy increase in the double electric layer during interaction with laser irradiance affects cathode supersaturation at the stage of crystallization. Hence, it also affects the penetration depth of electroplated material ions into the base metal, which leads to the adhesion strength enhancement. Practical value. On the basis of research results obtained during the laser-assisted electroplating of the structure and mechanical characteristics of nickel and zinc metal films, their connection with the laser irradiance parameters is found out. Laser irradiance application, depending on the electroplating mode (galvanostatic or potentiostatic) allows obtaining the equilibrium structure or, on the other hand, nonequilibrium structure.
About some aspects of explosion in the soils of artificial structures
Authors: Berbushenko V. P. , Marushyak O. V.
Published: April 2015

Purpose. To define actual and prospective research guidelines of the destruction of patchy soil masses under the influence of explosions as well as the peculiarities of the explosion waves expansion throughout the boundaries of mediums separation in artificial soils. Methodology. Methods of the study and analysis of published studies on the behavior of soils in the explosion are used, the research methods matching that were used in the investigation of the explosion in natural soils and for research in artificial soil. Findings. The analysis of scientific issues on the topic of soils’ behavior during explosions shows that the natural soils behavior during the explosions in the main explosive for the manufacturing mining-and-explosive works is considered. Originality. The study of nature of artificial soils’ behavior during explosions as well as the consequences prediction and the development of technologies of their liquidation is a very important task for the State Special Transport Service’s subunit. The task is urgent especially considering the current situation of existing threats. Research methods that are offered are not new, but in relation to artificial soils, they were not applied. Practical value. The list and the amount of threats, which exist in the present time, shows that it is necessary to know which consequences the explosions towards the grounds of transport objects may result in.
Research of properties of modern heat-insulation materials
Authors: Shcherbak A. S.
Published: April 2015

Purpose. To study the modern heat-insulating materials presented at the market of Ukraine and to estimate the efficiency of their application. Methodology. Research and analysis of heat-insulating materials presented at the market of Ukraine, according to the existing standards. Findings. To ensure the energy efficiency in buildings and constructions it is necessary to apply the domestic heat-insulating material, which possesses the given thermo technical characteristics, reduced indexes of water absorption, flammability and toxicity, as well as durability and relatively low self–cost. Originality. Basic heat-insulating materials, which are most widely used in construction are systematized, the researches of their properties are conducted and the foam glass is chosen as the most effective heat-insulating material. It is characterized by high thermo technical characteristics and possesses the best ecological indexes, as well as the sturdiness for aggressive factors influence. Practical value. Special attention deserves the insulating material foam glass, which is a synthetic silicate material with evenly placed pores (0.1 ... 5.0 mm) separated by thin septa with a vitreous substance possesses the necessary properties and by aforesaid may be accepted for studies aimed its improvement (modification). The results of researches can be applied in the foam glass production, which is used for heat-insulation of buildings and constructions, equipment, pipelines etc.
On the equivalence of safety criteria of the wheels derailment from the rails when using the directing or lateral force
Authors: Blokhin Ye. P. , Korotenko M. L. , Klimenko I. V.
Published: April 2015

Purpose. Clarification of safety criteria of the wheels derailment from the rails using either the lateral or the directing force. Methodology. Technique is connected with the analysis of safety criteria expressions of the wheels derailment from the rails, which use the lateral or the directing force in the position of limit equilibrium of the system, as well as with the analysis of expressions for the coefficient of stability from the wheels derailment from the rails when using the specified criteria. Findings. It is shown that the safety criteria of derailment, representing either the ratio of the lateral force to vertical one or the directing force ratio to the vertical one, which operate in the contact point of the climbing wheel flange with the rail head, are equivalent. As for the stability coefficient of derailment, it is shown that near to the safety limit their use yields almost the same results. Originality. The concept of the safety criteria, using the lateral or directing forces is specified and their equivalence is shown. Practical value. Obtained results allow one to use one of these two safety criteria expressions instead of two expressions cited in the normative literature, which gives the number of advantages for the processing of testing results. And the recommendations on the use of criteria, in which the ratio of lateral or directing forces to the vertical force acting in the contact point of the climbing wheel flange with the rail head were given.
Mathematical model for estimating of technical and technological indicators of railway stations operation
Authors: Kozachenko D. M.
Published: April 2015

Purpose. The article aims to create a mathematical model of the railway station functioning for the solving of problems of station technology development on the plan-schedule basis. Methodology. The methods of graph theory and object-oriented analysis are used as research methods. The model of the station activity plan-schedule includes a model of technical equipment of the station (plan-schedule net) and a model of the station functioning , which are formalized on the basis of parametric graphs. Findings. The presented model is implemented as an application to the graphics package AutoCAD. The software is developed in Visual LISP and Visual Basic. Taking into account that the construction of the plan-schedule is mostly a traditional process of adding, deleting, and modifying of icons, the developed interface is intuitively understandable for a technologist and practically does not require additional training. Originality. A mathematical model was created on the basis of the theory of graphs and object-oriented analysis in order to evaluate the technical and process of railway stations indicators; it is focused on solving problems of technology development of their work. Practical value. The proposed mathematical model is implemented as an application to the graphics package of AutoCAD. The presence of a mathematical model allows carrying out an automatic analysis of the plan-schedule and, thereby, reducing the period of its creation more than twice.
Automation of information decision support to improve e-learning resources quality
Authors: Danchenko A. L.
Published: April 2015

Purpose. In conditions of active development of e-learning the high quality of e-learning resources is very important. Providing the high quality of e-learning resources in situation with mass higher education and rapid obsolescence of information requires the automation of information decision support for improving the quality of e-learning resources by development of decision support system. Methodology. The problem is solved by methods of artificial intelligence. The knowledge base of information structure of decision support system that is based on frame model of knowledge representation and inference production rules are developed. Findings. According to the results of the analysis of life cycle processes and requirements to the e-learning resources quality the information model of the structure of the knowledge base of the decision support system, the inference rules for the automatically generating of recommendations and the software implementation are developed. Practical value. It is established that the basic requirements for quality are performance, validity, reliability and manufacturability. It is shown that the using of a software implementation of decision support system for researched courses gives a growth of the quality according to the complex quality criteria. The information structure of a knowledge base system to support decision-making and rules of inference can be used by methodologists and content developers of learning systems.
Power quality complex estimation at alternating current traction substations
Authors: Bosiy D. O.
Published: April 2015

Purpose. At alternating current traction substations are used three-winding transformers. This scheme comes to significant costs from power quality disturbances at each supplier. The most significant power quality indices at alternating current traction substation are voltage deviation, voltage unbalance and harmonic distortion. The purpose of this article is power quality complex estimation at two traction substations that work on the one district of traction network. Methodology. The measurements were made according to accepted program during 24 hours with 1 sec discretization. A few power quality analyzers PM175 are used to record data with time synchronization. The scheme of measurements means that devices are connected through current and potential transformers at the each level of voltage. Findings. Voltage level at different substation is various due to power losses in primary network. The voltage in one phase of 1-st substation is bigger than in other phases. Voltage THD values according to standard requirements are below norm only for primary 154 kV networks. For another traction and regional networks voltage THD values are above norm value. The voltage unbalances in 154 kV networks are below voltage unbalance in 35 kV networks. Besides the voltage unbalance in 154 kV network is below 2 % that complies with the requirements of standard. At the same time we can consider that voltage and current spectrums consist from discrete harmonics with frequencies that multiples of the fundamental frequency. Originality. Voltages at the connection points of traction substations to supply lines are complex stationary random process that determines the voltage mode of the external power supply system of each traction substation. The flows of active and reactive power of the higher harmonics at AC traction substation are directed opposite power of the fundamental harmonic. The power flows on higher harmonics create the disturbing impact on related devices. The total power at AC traction substation consists of 61,8 % of the active power, 32,5 % of the reactive power of the 1st harmonic and 5,7 % of the distortion power in the quadrature components. Practical value. Analysis of the quadrature components suggests that traditional approaches to reactive power compensation at the fundamental frequency will be sufficiently effective. But the influence of the distortion power on reducing energy losses must be also researched. Besides reactive power compensation should be considered with the issue of reducing the basic power quality indices to standardized values.
Fatigue damage accumulation of details in cars according to criterion of specific energy of total strain
Authors: Kulichenko A. Ya. , Kuzin N. O. , Vakulenko L. I.
Published: April 2015

Purpose. Modern ideas about the accumulation of fatigue damages in the details of railway vehicles are based on models that estimate the durability of metal systems and depend on the number of cycles and the magnitude of deformations or stresses. These models allow one to assess with a sufficient degree of adequacy the weakening of metal systems in polycyclic fatigue and at the presence of the elastic strain only in the details of rolling stock. However, the possibility of plastic deformation appearing during operation of rail transport structures is not taken into account. The aim of this work is a construction of a mathematical model that allows estimating the durability of metal systems with regard to the appearing of the plastic component in the process of deformation of parts of railway vehicles. Methodology. With the use of modern methods of solid mechanics the influence of the parameters of plastic deformation on the durability of highly loaded structural elements was analyzed. Findings. The effect of elastic and plastic deformation on the energy dissipation under cyclic loading was studied. Originality. It was shown analytically that the softening parameters of metal systems are related to the total energy of deformation, which characterizes features of the degradation processes in the metal structures under external loads. Practical value. Ratios were proposed, they allow estimating residual life of details in a sequential multilevel cyclic loading.
Theoretical and experimental evaluation of strength indices for traction reduction-gear housings of welded construction KEVRZ for electric trains ER2, ER9
Authors: Bondarev O. M. , Yagoda D. O. , Bondarev O. O. , Skoblenko V. M.
Published: April 2015

Purpose. To check meeting the requirements of Standards for experimental specimens of traction gear boxes for electric trains of series ER2, ER9 with housings of welded construction by Kiev Electric Wagon Repair Works (KEVRZ). Methodology. To reach the objective in hand, performing the work, some computational models for theoretical determination of the stress levels in the reduction-gear housing of welded construction by simulating the loading conditions that can take place during the operation have been developed and the stresses at different points of the reduction-gear housing as well as the levels of vertical accelerations of the reduction-gear housing and loading of the unit of connecting the housing to the bodies frame have been experimentally evaluated. Findings. On the basis of analysis of the calculation results obtained meeting the requirements of Standards for traction reduction gears with the housings of welded construction by KEVRZ has been found. Originality. Based on the experimental and theoretical investigations, the scientific support of works on developing and putting into operation the renovated traction reduction gears for electric trains of series ER2, ER9 has been completed. Practical value. A technical solution with the measures to be fulfilled in operation of electric trains of the mentioned series with traction reduction-gear housings of welded construction by KEVRZ has been developed and given to experts of Ukrzaliznytsia to introduce the proposed measures during repairs.