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Thermodynamically, bosons and fermions differ by their statistics only. A general entropy functional is proposed by superposition of entropic terms, typical for different quantum gases. The statistical properties of the corresponding Janus particles are derived by variation of the weight of the boson/fermion fraction. It is shown that di-bosons and anti-fermions separate in gas and liquid phases, while three-phase equilibrium appears for poly-boson/fermion Janus particles.
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One of the essential and worthwhile characteristics of modern times is the rapid implementation of information and information technologies in life. As a result, there is a soaring need for more adequate and affective means of presenting and absorbing information. In connection with this, the problem concerning the role and the place of the Physics experiment in education in Physics has recently gained popularity. This is why in the conditions of the contemporary development of communication, the fundamental aims of education are: formation of knowledge and skills in the Physics experiments and their use in students’ creative activities.The problem concerning the implementation of the Physics experiment in Physics is urgent, complex and multifaceted.
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The article is devoted to а methodology of determining the number of the roots of a class of cubic algebraic equations with real parameters in which one of the roots can be determined directly. A more general approach is presented too using derivatives and graphical representations of functions.
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The paper considers interesting proofs of two algebraic inequalities.
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This research studies a kinetics of photo-electro-assisted degradation of dyes. The kinetics study applied the Buttler-Volmer kinetics for electro-assisted reaction in combination with the regular chemical kinetics for photodegradation. The result then being compared with the regular chemical kinetics application for both photo-electro-assisted degradation. The degradation cell was designed by separating the anodic and cathodic cell, in which the dye solution was placed in the anodic cell. As the solvent, water molecules, also be able to undergo electro-oxidation, therefore in this research pH of the solution was recorded during reaction whether in the anodic or cathodic cell. The result shows that oxidation of H2O occured in an anodic cell in competition with the dye oxidation. However, the dye oxidation proceeds faster than H2O oxidation. In which, the rate constant of dye oxidation is 2.7795 × 10-3. Meanwhile, the rate constant of H2O oxidation in the anodic cell is 7.9738 × 10-11. In addition, the study also found that the degradation cell undergoes polarization. It is indicated by the low value of the cathodic rate constant, i.e. 3.2805 × 10-10. The cathodic cell is only filled with water, therefore, the reducing species is only H2O molecules. The result also shows that Cu-TiO2/Graphite also has adsorption ability in which the dye molecules were adsorbed with adsorption constant of 5.56 ×10-2 ppm-1.
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The blending of chitosan with different types of silica-based reinforcement materials, kaolin clay and (3-glycidyloxypropyl) trimethoxysilane via solution casting method had been carried out. This study was focused on the mechanical, water uptake and swelling area comparison between chitosan/kaolin (referred as Cs/Kao) and chitosan/(3-glycidyloxypropyl) trimethoxysilane (Cs/GPTMS) composites. Fourier transform infra-red (FTIR) characterization was also conducted in this study for functional group analysis. Mechanical properties, such as tensile strength, elongation percentage and young’s modulus, were performed according to ASTM D882-02 standard method. Based on the mechanical test, it can be concluded that different types of silica-based reinforcement materials resulted different mechanical properties. The GPTMS filled chitosan had higher tensile strength value than Cs/Kao at 15% filler loading but lower in another concentrations. Moreover, water uptake and swelling area value of Cs/GPTMS was lower than Cs/Kao at 15% filler content.
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The forward rate constant of reversible reactions can be used to estimate the concentration of the reactants at a given time (and then the products by using stoichiometric coefficients), to control the quality of the products, to calculate the backward rate constant (by using equilibrium constant), to determine the activation energy, and to predict the reaction mechanisms. Most commonly, the determination of a forward rate constant is done by using the equilibrium concentrations. However, this approach is inefficient since to a certain extent a lot of reactions takes a long time to reach an equilibrium state. The method without using equilibrium concentration is also introduced. Nevertheless, it cannot be used to determine the backward rate constant. This study presents a simple and appropriate technique, using irreversible approach on three data at the early stages of a reversible reaction. The data for first order for both directions and first order for forward and second order for back reaction were obtained from literatures. The results were then compared with that obtained from conventional technique. The results show that, with error percentage less than 5%, the new technique is valid and reliable.
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A series of heteroarylamino-chromen-2-ones 4(a-c) were synthesized by condensation reactions under catalytic conditions. 5-(3-Nitro-2-oxo-2H-chromen-4-ylamino)-3H-imidazole-4-carboxamide 4a, 4-(7-Hydroxy-5-methyl-[1,8]-naphthyridin-2-ylamino)-3-nitrochromen-2-one 4b and 4-(4-methylbenzothiazol-2-ylamino)-3-nitrochromen-2-ones 4(c-d) were synthesized by condensation of 4-chloro-3-nitrochromen-2-one 2 with corresponding heteroarylamines 3(a-d) under reflux reaction conditions. Alkali hydrolysis of compounds 4(a-d) afforded the 2-hydroxy-ω-nitroacetophenone 5. The structures of the obtained compounds were established on the basis of FTIR and NMR spectrometric data and their elemental analysis. Compounds of series 4(a-c) were screened for their antibacterial activity against S. aureus, E. coli and Klebsiella by Diffusion Disc Method. Compounds 4(a-c) displayed considerable activity against these microorganisms and the impact of substitutions in antimicrobial activity was also explored.
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On the basis of the analysis of actual material basic of innovative technologies of modern andragonical services and their cultural meaning are found out and structured. Methodology. The methodology of the scientific research is based on the modern philosophical paradigm of cultural and art education in its relation to cultural-creative status. The author uses the methods of system analysis, synthesis, and comparison. Scientific Novelty. A scientific novelty consists of the research of correlation of cultural maintenance and innovations in context of andragony. It is proven that cultural-creative, as the phenomenon, worth to examine as a process and as end-point as consumers of andragonical services of the Rivne centre are workers of establishments of culture, teachers of musical and artistic schools. Such variety of categories of listeners stipulates the variation of andragonical services. The author’s attention is paid to the fact that cultural-generating possibilities of innovative technologies will be realized in such kinds and forms as illustrative, problem lectures, situation exercises, master classes, practical works, planners, consultations with experts, excursions, business, role plays, analysis of productive situations, «brainstorming», «methodical panoramas», «work in a pair», dialogue with listeners, «microphone», portfolio, creative reports, creative portraits, presentations, sequences, «round table», pitching, case-method. The choice of technology depends on: categories of listeners, themes of employment, its aim and actuality, accordance of maintenance and form, a context; a level of preparedness of listeners, presence of technical and the Internet of possibilities, creativity of a teacher, his experience, experience of work, a motive is to the self-education, self-development, studies during life. The synergy of these criteria gives a cultural-creative result. The dynamic development of cultural-creative maintenance of innovative technologies is illustrated by the most prime examples of their use by teachers. Conclusions. A culture and work are consonant in andragonical process of preparations of cultural and art specialists in a synergy with innovative technologies. Professional creation of culture is provided by the active and interactive models of communication in such segments as the use by teachers in the lessons on professional disciplines; generalization and acquaintance of listeners with existent modern experience of innovations on lessons of methodology of studies; providing listeners with methodical developments in the sphere of technology of realization of innovative studying process; a selection and demonstration of innovations that can be found in Internet today; the videotape recording of innovative lessons in the Rivne centre and placing them on an official web-site.
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A new azo dye ligand from 4-aminoantipyrine and 5-bromosalicylaldehyde that is 4-(2’-hydroxy-3’-formyl-5’-bromophenylazo)antipyrine and its Co(II), Ni(II), Cu(II) and Zn(II) complexes have been synthesized. The ligand and its metal complexes have been characterized by various techniques like analytical, IR, NMR, electronic, magnetic susceptibility, thermal, XRD and molecular modeling study. The spectral and analytical study predicts tridentate nature of the ligand, distorted octahedral geometry for Co(II), Ni(II) and Cu(II) complexes and distorted tetrahedral geometry for Zn(II) complex. The Computational study of the ligand and its metal complexes predicts global reactive descriptors and geometrical parameters. The thermal study of the Ni(II) complex reveals its thermal stability and fluorescence study of the ligand and its Zn(II) complex indicates their photo conducting properties. The XRD study of the Cu(II) complex reveals tetragonal crystal system for the complex. The investing compounds are potential bactericides as indicated from their antibacterial study and DNA binding study of the compounds indicates their DNA binding ability.
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The article discusses one key characteristic of irreversible processes: in order to bring the system back to its original state following such a process, some energy is inevitably dissipated as heat into the surroundings. Greater dissipation indicates greater irreversibility. In the limit that the amount of energy dissipated approaches zero, the process is said to be reversible. This concept is illustrated by considering isothermal expansion of an ideal gas, free expansion of an ideal gas into vacuum, heat transfer from a hotter object to a colder one, phase change, and chemical reactions.
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TiO2-M (M = Cd, Co, Mn) were synthesized by sol-gel method using titanium(IV) isopropoxide (TTIP) and cadmium sulfate octahydrate (CdSO4.8H2O), manganese(II) sulfate monohydrate (MnSO4.H2O), cobalt(II) sulfate heptahydrate (CoSO4.7H2O) as precursors. M-doped TiO2 was performed with molar ratio 1:3; 1:2; 1:1; 2:1; 3:1 (mol Ti / mol M) and photocatalytic processes using visible light with irradiation time for 5, 10, 15, 20, 25 and 30 minutes. This study was carried out to determine the effect of different metal ions, the composition of Ti:M and the exposure time on the photocatalytic degradation of methylene blue dye. The results showed that different metal ions influenced crystal size and affected electronic properties (band gap). Crystal size of TiO2 > TiO2-Mn > TiO2-Co > TiO2-Cd and band gap of TiO2 > TiO2-Cd > TiO2-Co > TiO2-Mn. In addition, differences of Ti:M composition also influenced the photocatalytic activity. The longer of applied time exposure, the higher photocatalytic degradation of methylene blue was achieved. The optimum composition of Ti:M was obtained at Ti:M ratio by 3:1 with degradation values by 92.56% (TiO2-Cd), 90.44% (TiO2-Co), and 89.42% (TiO2-Mn).
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We present an innovative electromotive force (EMF) measurement technique to study the kinetic behavior during alkaline hydrolysis of ethyl acetate. The explicit feature of this research is the application of green chemistry ideas that are inherent in the experiment. Using the new approach, we find that the kinetic behavior of the reaction under study follows second order with an estimated rate constant value at 25°C to be 2.45 × 10-3 cm–3 min–1. This value is in excellent agreement with the conventional end-point neutralization titration method discussed previously in the literature. The novel EMF measurement technique is simple, fast, accurate and eco-friendly. Keeping in view of long-term sustainability of the ecosystem, we feel that there is an urgent need to switch over from conventional laboratory practices to green chemistry approaches. Further, the method discussed here may prove to be extremely useful for teachers, researchers and students who wish to carry out kinetic study of other systems.
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The objective of this study was to verify an impact of different Cd ion concentrations on metabolic (biochemical) parameters in blood of egg chickens. Taking in to consideration that change of these values reflects the level of damage of the vital organs like liver, kidneys, hart etc. These vital organs determine the health status, growth and development of organisms. In the total of four groups of chickens have been included in the experiment. Three groups were treated with different concentrations of cadmium (2, 4 and 6 mg/kg) while one group was set as a control group without treatment. Eleven different biochemical parameters have been measured and analyzed such as: total proteins, albumins, globulins, aspartate transaminase, alanine transaminase, lactate dehydrogenase, gamma-glutamyl transferase, alkaline phosphatase, blood urea nitrogen, creatinine and glucose. The results indicate the significant changes on the level of biochemical parameters in blood, by increasing the cadmium concentration. The level of albumins, alanine transaminase, lactate dehydrogenase, gamma-glytamyl transferase, and creatinine has been decreased significantly compared to control group while other parameters were increased. The biochemical parameters between treatments were changed significantly. Total levels of proteins, globulins, aspartate transaminase, alanine transaminase, gamma-glutamyl transferase, creatinine and glucose has been increase by increased the cadmium concentration. While in another hand, biochemical parameters such as lactate dehydrogenase and alkaline phosphatase has been decreased significantly when the Cadmium was increased. Changes on biochemical parameters are an indication showing that, cadmium effects are negatively oriented on metabolic processes of feed on egg-layer chickens.
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The antioxidant capacities, total phenolic and flavonoid content of five different extracts (Et2O, CHCl3, EtOAc, n-BuOH and H2O) of Primula veris (L.) growing wild in Kosovo were analyzed. Total phenolic and flavonoid content were quantitatively determined to the Primula veris (L.) growing wild in North-Western part of Kosovo in two different altitude levels (670 m and 1200 m). The amount of total phenolics in Primula veris (L.) extracts ranged from 5.10 mg GAE/g d.e. in altitude 1200 m to 17.30 mg GAE/g d.e. in altitude 670 m. The amount of total flavonoids in Primula veris (L.) extracts ranged from 12.15 mg RE/g d.e. in altitude 670 m to 31.43 mg GAE/g d.e. in altitude 1200 m. Free radical scavenging capacity (RSC) was evaluated by measuring the scavenging capacity of extracts on DPPH, NO as well as on hydrogen peroxide (H2O2). EtOAc, n-BuOH and H2O extracts of Primula veris (L.) expressed very strong scavenger activity. On the other hand, Et2O and CHCl3 extracts showed much weaker effect in the neutralization of DPPH, NO and H2O2. The observed differences in antioxidant activity could be partially explained by the levels of phenolics and flavonoids in extracts of Primula veris (L.). Hence, this plant can be used to discover bioactive natural products that may serve as leads in the development of new pharmaceuticals.
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This paper examines the use of visual feedback technology in the field of vocal pedagogy. This technology enables singers to “see” what their voices are doing while they are singing, by recording certain acoustic properties of their voice. It also analyzes the existing computer programs, designed to provide visual feedback on acoustic parameters of the singing voice and to investigate how such feedback can most effectively be utilized in the vocal pedagogy.
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Total phenols, flavonoids, flavonols and anthocyanis content and antioxidant activity were quantitatively determined to the Tussilago fatfara (L.) growing wild in Sharr (South part of Kosova). In the tested extracts of plant species Tussilago fatfara (L.) quantitative composition of total phenols, flavonoids, flavonols and anthocyanins were determined by spectrophotometric method. Total phenols determined by Folin-Ciocalteu reagent and their amounts in the range of 56.50 mg/g to 84.70 mg/g (expressed as gallic acid equivalent, mg GAE/g). The amounts of flavonoids in plant extracts are in the range of 2.75 mg/g to 8.76 mg/g (expressed as rutin equivalent, mg RE/g).The amount of total flavonols in Tussilago farfara (L.) extracts ranged from 0.21 mg RE/g to 0.51 mg RE/g. The contents of total anthocyanosides in the Tussilago farfara (L) ranged from 1.44 (ethanol extract) to 1.86 (acetone extract) anthocyanins determined as mg yanidin 3-glucoside/g dry weight. Antioxidative activity was determined in vitro, using the DPPH reagent by spectrophotometric method.The results demonstrated that extract RSC was dependent on the solvent polarity, and the type of free radical used in the reaction. The IC50 values extracts in DPPH• assay was from 0.10 mg/ml (ethanol extract) to 0.20 mg/ml (acetone extract).
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