Lecture Course “Modern Physics”

In the paper, the structure of the lecture course “Modern Physics” is described in detail. The course is based on a logical presentation of modern ideas about quantum-, atomic-, nuclear-, and molecular physics as well as astrophysics. A special attention is paid to a relatively new interdisciplinary research field, namely the physics of open systems, and to the study of clusters as one of the most promising scientific areas. Separate chapters of the textbook are devoted to nonlinear optics, quantum information, structure and dynamics of molecules. The fundamental laws and concepts of modern physics, their relationship and origin are comprehensively discussed. It is underlined that this lecture course is intended, first of all, for students of technical universities, postgraduate students of relevant specialties, as well as professors of vocation-related subjects. The inclusion of new sections of physics in the curricula of universities is rationalized, in particular, by the fact that physics is closely related to engineering. Due to this fact, the important role that physics plays in society becomes especially evident. The paper may also be of interest to those who are fond of physics and its state-of-the art

Methods of introducing a fine additive based on the TiO2 –Bi2 O3 system into cement compositions

Introduction. Modification of traditional materials based on mineral binders with fine-dispersed and nano-additives is an essential way to create new functional construction materials with a set of unique characteristics. However, the main difficulty in this process is the method of introducing a finely dispersed component into the cement matrix and the uniformity of its distribution. The homogeneous distribution of the additive particles in the cement composite improves the physical and mechanical characteristics, intensifies the hydration of cement clinker minerals, and is leading to a more durable and dense cement stone structure. The main methods of introducing additives into the cement composition include joint grinding, dry mixing and the introduction of a stabilized suspension of the additive instead of mixing water. Thus, the purpose of this research is to compare the options for the introduction of additives based on the TiO2–Bi2O3 oxide system, which can provide the cement composite with improved physical, mechanical and structural characteristics and the ability to resist mold fouling. The object of this research is the cement compositions modified with an additive based on the TiO2–Bi2O3 system. Materials and methods. The studies were carried out to establish the optimal method of introducing a fine-dispersed additive based on the TiO2–Bi2O3 system. At the first stage, the phase and granulometric composition of the additive was studied, then the additive was introduced into the cement composition in four different ways. The cement stone samples were obtained by dry mixing of the components then mixed with water, by mixing cement powder with water suspension of the additive after ultrasound processing, by mixing a dry mixture of cement and an additive with water-plasticizer solution, and cement powder mixed with water-polymer suspension of the additive after ultrasound processing. After that, the strength characteristics, porosity and ability of the samples to resist fungi fouling were investigated. Results. As a result of the study, the authors concluded that the highest physical and mechanical characteristics of cement stone can be provided by introducing an additive in the form of a stabilized water-polymer suspension. This method contributes to the formation of a more durable and dense structure of cement stone, with an increase in strength of 31; 38 and 44.8% at first day age, 28; 30 and 32% at third day age and 2.4; 9.0 and 14% at 28 days age relative to the control sample containing cement, water and plasticizer. It was found that the highest strength results were shown by a sample containing a stabilized suspension of an additive with a concentration of 50 g/l. The study of the cement stone porosity showed its decrease by 13% at first day age in relation to the control sample with a plasticizer, and by 10% after 28 days of hardening. It was also shown that samples modified with 50 g/l (1.7 wt.%) of the additive demonstrate resistance to bio-fouling. Conclusion. As a result of the research, the authors concluded that the optimal way to introduce a finely \ud dispersed additive based on the TiO2–Bi2O3 system is to mix cement powder with a stabilized water-polymer suspension of the additive, resulting in a more durable and dense structure of cement stone, especially at an early stage of hydration, which can also resist fungi bio-fouling. Thus, the authors came to the conclusion that the cement compositions obtained by this method can be applied as repair compounds and tile grout in damp shaded rooms with favorable conditions for fungi colonization

Methodological Substantiation of the choice for a stabilizer for bismuth titanate fine particles suspensions

ABSTRACT: Introduction. The current stage of the construction industry and building materials science development involves the introduction and widespread application of nano- and fine particles capable of improving the properties of traditional materials. However, it is necessary to provide stabilization of nano- and fine-dispersed components in the cement system. Plasticizing additives can be used as stabilizers. It is important to set their concentration. Therefore, the purpose of this study is outlined, which lays in the methodological substantiation the stabilizing effect of various types of plasticizers on the suspension of fine synthetic bismuth titanate used in the modification of cement systems, and the establishment of the limits of their optimal concentrations. Materials and methods. The research is aimed at establishing the limits of optimal concentrations of polycarboxylate and sulfonaphthalene formaldehyde plasticizers. The limits of plasticizers optimal concentrationsis determined withdye solubilization method, surface tension and conductometric methods, and studies on establishing the stabilizing effect of plasticizers on a bismuth titanate fine particles suspension. Results and discussion. To establish the limits of the optimal concentration capable of stabilizing fine particles of bismuth titanate in suspension, CMC is determined by the dye solubilization method, surface tension and conductometric methods. It is found that a polycarboxylate plasticizer is characterized by one CMC point, and a sulfonaphthalinformaldehyde plasticizer is characterized by two CMC points: CMC1 and CMC2. At CMC1 point unstable spherical micelles are formed, which turn into stable ones at the CMC2 point. At concentrations exceeding the CMC2 value, polymorphic transformations of spherical micelles into nonspherical asymmetric micelles occur. The same can be traced for the polycarboxylate plasticizer CMC only in one stage. It can also be concluded that it is not reasonable to increase the plasticizer concentration above CMC for polycarboxylate plasticizer and above CMC2 for sulfonaphthalinformaldehyde plasticizer, which is due to structural changes in the micelles of plasticizers. It is assumed that in order to stabilize bismuth titanate fine particles, it is necessary to choose the plasticizers concentration within the limits not exceeding the values of CMC for polycarboxylate plasticizer and CMC2 for sulfonaphthalinformaldehyde plasticizer. Conclusion. Concluding results demonstrate the limits of optimal plasticizers concentrations for the stabilization of bismuth titanate fine particles suspension. For polycarboxylate plasticizer this range of concentrations is 1.1 – 1.5 g/l; for sulfonaphthalinformaldehyde plasticizer its 2.2 – 4.0 g/l

Exploring the Surface Chemistry for the Stabilization of Bismuth Titanate Fine Particle Suspensions in Cement Systems

ABSTRACT: Introduction. The evolution of the construction industry in its current stage calls for the alteration of traditional building materials through the incorporation of nano- and fine-dispersed additives. These additions confer new, unique attributes to cement-based construction materials, enabling control over structure formation processes. Consequently, this allows for the creation of materials with specifically defined characteristics. Additives can be introduced into the cement composite during the joint grinding with clinker minerals, as a component of dry building mixture, or in the form of a suspension instead of mixing water. Therefore, it is essential to obtain fine particles suspensions resistant to aggregation and sedimentation. Thus, the purpose of this study is to obtain stabilized suspensions of bismuth titanate fine particles for cement systems and to study the properties of modified cement stone. Materials and methods. The purpose of this work was to establish the optimal concentration of polycarboxylate plasticizer in industrial water, necessary for the stabilization of fine bismuth titanate suspensions using surface tension and conductometric determination methods, the sedimentation stability of the obtained suspensions and the effect of ultrasonic exposure, as well as the physical and mechanical characteristics of cement stone modified with the obtained suspensions. Results and discussion. In order to establish the optimal concentration of the plasticizer necessary to obtain stable suspensions of bismuth titanate particles, the critical micelle concentration (CMC) for the plasticizer was determined with tap water as the dispersed medium. The CMC value was 1.3 g/l. If the concentration exceeds CMC, the process of micelle formation begins. In the micellar form, the plasticizer no longer provides stabilizing effect on the additive particles, therefore, the concentration of the plasticizer should be lower than the CMC. It was also found that ultrasound exposure increases the sedimentation stability of suspensions. The resulting stabilized suspensions were used instead of mixing water to obtain modified cement stone samples. There is an increase in the compressive strength of cement stone samples obtained after the introduction of fine bismuth titanate into the cement composite in the form of water suspensions stabilized by ultrasonic treatment with concentrations of 10, 30 and 50 g/l. The increase in compressive strength of modified samples compared to reference sample was from 24 to 33 MPa at first day age (by 13, 25 and 38% respectively), and from 80 to 93 MPa at 28 days age (by 4, 9 and 16%). Compressive strength of samples modified with bismuth titanate suspensions after ultrasonication compared to reference sample with plasticizer increased mostly at the first and third days age: from 29 to 42 MPa (by 31, 38 and 45%) and from 53 to 70 MPa (by 28, 30 and 32%) respectively. Conclusion. As a result of the research carried out in this study, the Critical Micelle Concentration (CMC) of a polycarboxylate plasticizer was determined, optimal for stabilizing fine-dispersed additive of bismuth titanate for cement systems, the effectiveness of ultrasonic treatment to achieve sedimentation stability of the obtained suspensions of the additive was confirmed, an increase in the strength characteristics of modified cement stone samples was established both in the initial hardening periods and at 28 days age. The results allow to consider a cement composite with fine bismuth titanate as a basis for obtaining building materials of new generation

Transcriptional Analysis of Arabidopsis thaliana Response to Lima Bean Volatiles

Exposure of plants to herbivore-induced plant volatiles (HIPVs) alters their resistance to herbivores. However, the whole-genome transcriptional responses of treated plants remain unknown, and the signal pathways that produce HIPVs are also unclear.Time course patterns of the gene expression of Arabidopsis thaliana exposed to Lima bean volatiles were examined using Affymetrix ATH1 genome arrays. Results showed that A. thaliana received and responded to leafminer-induced volatiles from Lima beans through up-regulation of genes related to the ethylene (ET) and jasmonic acid pathways. Time course analysis revealed strong and partly qualitative differences in the responses between exposure at 24 and that at 48 h. Further experiments using either A. thaliana ET mutant ein2-1 or A. thaliana jasmonic acid mutant coi1-2 indicated that both pathways are involved in the volatile response process but that the ET pathway is indispensable for detecting volatiles. Moreover, transcriptional comparisons showed that plant responses to larval feeding do not merely magnify the volatile response process. Finally, (Z)-3-hexen-ol, ocimene, (3E)-4,8-dimethyl-1,3,7-nonatriene, and (3E,7E)-4,8,12-trimethyl-1,3,7,11-tridecatetraene triggered responses in A. thaliana similar to those induced by the entire suite of Lima bean volatiles after 24 and 48 h.This study shows that the transcriptional responses of plants to HIPVs become stronger as treatment time increases and that ET signals are critical during this process

Phylogenomic Mining of the Mints Reveals Multiple Mechanisms Contributing to the Evolution of Chemical Diversity in Lamiaceae

The evolution of chemical complexity has been a major driver of plant diversification, with novel compounds serving as key innovations. The species-rich mint family (Lamiaceae) produces an enormous variety of compounds that act as attractants and defense molecules in nature and are used widely by humans as flavor additives, fragrances, and anti-herbivory agents. To elucidate the mechanisms by which such diversity evolved, we combined leaf transcriptome data from 48 Lamiaceae species and four outgroups with a robust phylogeny and chemical analyses of three terpenoid classes (monoterpenes, sesquiterpenes, and iridoids) that share and compete for precursors. Our integrated chemical–genomic–phylogenetic approach revealed that: (1) gene family expansion rather than increased enzyme promiscuity of terpene synthases is correlated with mono- and sesquiterpene diversity; (2) differential expression of core genes within the iridoid biosynthetic pathway is associated with iridoid presence/absence; (3) generally, production of iridoids and canonical monoterpenes appears to be inversely correlated; and (4) iridoid biosynthesis is significantly associated with expression of geraniol synthase, which diverts metabolic flux away from canonical monoterpenes, suggesting that competition for common precursors can be a central control point in specialized metabolism. These results suggest that multiple mechanisms contributed to the evolution of chemodiversity in this economically important family. The mint family (Lamiaceae) includes many culturally and economically important species and collectively exhibits an exceptionally high degree of chemical diversity. Using an integrated chemical-genomic-phylogenetic approach, gene family expansion, altered gene expression of key biosynthetic pathway genes, and flux of precursors were shown to underlie the evolution of chemodiversity observed in this chemically rich clade

Root-emitted volatile organic compounds: can they mediate belowground plant-plant interactions?

peer reviewedBackground Aboveground, plants release volatile organic compounds (VOCs) that act as chemical signals between neighbouring plants. It is now well documented that VOCs emitted by the roots in the plant rhizosphere also play important ecological roles in the soil ecosystem, notably in plant defence because they are involved in interactions between plants, phytophagous pests and organisms of the third trophic level. The roles played by root-emitted VOCs in between- and within-plant signalling, however, are still poorly documented in the scientific literature. Scope Given that (1) plants release volatile cues mediating plant-plant interactions aboveground, (2) roots can detect the chemical signals originating from their neighbours, and (3) roots release VOCs involved in biotic interactions belowground, the aim of this paper is to discuss the roles of VOCs in between- and within-plant signalling belowground. We also highlight the technical challenges associated with the analysis of root-emitted VOCs and the design of experiments targeting volatile-mediated root-root interactions. Conclusions We conclude that root-root interactions mediated by volatile cues deserve more research attention and that both the analytical tools and methods developed to study the ecological roles played by VOCs in interplant signalling aboveground can be adapted to focus on the roles played by root-emitted VOCs in between- and within-plant signalling

Verification of a investment appeal assessment technique of the IT introduction project at the hi-tech knowledge-intensive enterprise

Need of an assessment of investment appeal of projects, according to authors, is caused also by the fact that the investment project is the independent object of the analysis entering the general program of development, both the knowledge-intensive enterprise, and economy in general. Results of the investment analysis allow the potential owner to determine the term necessary for return of originally invested sum, to calculate real increments of assets from acquisition of property, to estimate potential stability to risks of the cash flow formed by concrete object of property. In article features of an assessment of investment appeal of innovative projects on introduction of information technologies are considered. Methodical approach to innovative development of the knowledge-intensive enterprise is created. Within this approach the main evaluation stages are defined, approaches to an assessment of a discountrate of the IT and innovative project are specified, calculation of key indicators of investment appeal of the innovative project is made. The offered assessment procedure of investment appeal of the investment project of introduction of information technologies will allow the enterprise to choose an optimal variant of implementation of IT solutions which will give the chance to solve the problems revealed during an assessment of his activity. Research is based on the theoretical and methodological provisions, classical and modern fundamental concepts which are contained in works of classics of economic and administrative science and also the domestic and foreign scientists working in the field of the organization and management, the organization and management of innovative development of the knowledge-intensive enterprises. For the solution of the tasks set in article the complex of scientific basic and applied theories, approaches and methods has been used, namely: theory of systems and system analysis, theory of management, theory of decision-making, theory of innovations, theory of cost and interested persons, process and system approach, and also methods of mathematical modeling, logical analysis and empirical research, etc

The role of matrix metalloproteinase-9 in the genesis of chronic bronchi inflammation in children with bronchial asthma

Bronchial asthma as the most common respiratory tract disease is an urgent problem of modern medicine. Matrix metalloproteinases (MMР) play a significant role in the processes of inflammation maintaining and bronchi remodeling in children with bronchial asthma.Objective: To study the role and inheritance of MMR9 in the bronchial asthma pathogenesis in children.Characteristics of children and research methods. The authors carried out the prospective study of 54 children with bronchial asthma and 56 healthy children with the determination of the MMP-9 level in blood serum, as well as the polymorphic variant 8202A>G of MMP9 gene.Results. Children with bronchial asthma had significantly higher content of MMP9 in the blood serum (431.76 [306.15; 612.93] ng/ml), as compared to the control group (276.05 [160.33; 397.02] ng/ml). When studying polymorphism 8202A>G of MMP9 gene in the examined patients it was found that the children with bronchial asthma had the G allele a little more often (57.5%) than A allele (42.5%). Heterozygous carriers of the MMP9 gene polymorphic variant predominate both among the patients with bronchial asthma and in the control group. When comparing the frequency of genotypes and alleles in the group of children with bronchial asthma and control group the authors revealed no statistically significant differences.Conclusion. The disease mechanism significantly depends upon the MMR9 concentration in the serum of patients with bronchial asthma and the peculiarities of this enzyme inheritance

Experimentally Studied Thermal Piston-head State of the Internal-Combustion Engine with a Thermal Layer Formed by Micro-Arc Oxidation Method

The paper presents results of experimental study to show the efficiency of reducing thermal tension of internal combustion engine (ICE) pistons through forming a thermal barrier coating on the piston-head. During the engine operation the piston is under the most thermal stress. High temperatures in the combustion chamber may lead to the piston-head burnout and destruction and engine failure.Micro-arc oxidation (MAO) method was selected as the technology to create a thermal barrier coating. MAO technology allows us to form the ceramic coating with a thickness of 400μm on the surface of aluminum alloy, which have high heat resistance, and have good adhesion to the substrate even under thermal cycling stresses.Deliverables of MAO method used to protect pistons described in the scientific literature are insufficient, as they are either calculated or experimentally obtained at the special plants (units), which do not reproduce piston operation in a real engine. This work aims to fill this gap. The aim of the work is an experimental study of the thermal protective ability of MAO-layer formed on the piston-head with simulation of thermal processes of the real engine.The tests were performed on a specially designed and manufactured stand free of motor, which reproduces operation conditions maximum close to those of the real engine. The piston is heated by a fire source - gas burner with isobutene balloon, cooling is carried out by the water circulation system through the water-cooling jacket.Tests have been conducted to compare the thermal state of the regular engine piston without thermal protection and the piston with a heat layer formed on the piston-head by MAO method. The study findings show that the thermal protective MAO-layer with thickness of 100μm allows us to reduce thermal tension of piston on average by 8,5 %. Thus at high temperatures there is the most pronounced effect that is important for the uprated engines.The obtained findings can be used when designing and manufacturing the ICE with aluminum-alloy pistons.</p