Self-assembled metallic nanoparticle template --- a new approach of surface nanostructuring at nanometer scale

In the present work, the formation of silver and copper nanostructures on highly oriented pyrolytic graphite (HOPG) modified with self-assembled gold nanoparticles (Au NPs) is demonstrated. Surface patterning with nanometer resolution was achieved. Different methods such as field emission scanning electron microscopy (FEGSEM), energy dispersive spectrometry (EDS) and X-ray photoelectron spectroscopy (XPS) were used to illustrate a selective deposition of silver and copper on Au NPs. The mechanism of silver and copper ions reduction on Au NP with $n$-dodecanethiol coating is discussed.Comment: 6 pages, 3 figure

Effective index approximations of photonic crystal slabs: a 2-to-1-D assessment

The optical properties of slab-like photonic crystals are often discussed on the basis of effective index (EI) approximations, where a 2-D effective refractive index profile replaces the actual 3-D structure. Our aim is to assess this approximation by analogous steps that reduce finite 2-D waveguide Bragg-gratings (to be seen as sections through 3-D PC slabs and membranes) to 1-D problems, which are tractable by common transfer matrix methods. Application of the EI method is disputable in particular in cases where locally no guided modes are supported, as in the holes of a PC membrane. A variational procedure permits to derive suitable effective permittivities even in these cases. Depending on the structural properties, these values can well turn out to be lower than one, or even be negative. Both the “standard” and the variational procedures are compared with reference data, generated by a rigorous 2-D Helmholtz solver, for a series of example structures.\u

Estimate of the possibility of conducting mass spectrometric measurements of the matter of lunar surface

Electron beams studied for use in lunar soil spectrometric analysi

Did DR-CAFTA Affect the Exports of the Dominican Republic to the United States?

This article evaluates the impact the Dominican Republic and Central America Free Trade Agreement (DR-CAFTA) had on the exports of the Dominican Republic (DR) to the United States. We estimate a gravity model for the DR exports to the 109 trade partners of the country from 1990 to 2014. This model quantifies the effect of the DR-CAFTA since 2007, when the agreement was ratified, and finds that the DR-CAFTA negatively affected DR exports to the US. We conduct further analysis of factors that could explain the decline in exports, in spite of the ratification of the agreement. We find that the 2008–09 crisis was not the driver of the slowdown of DR exports to the US. The increasing competition with Central American countries and other export oriented economies, like China, in the US market seem to have the leading role in the export contraction that we find in our study

Strength diagrams of fibrous composites with unidirectional structure

The dependence of the composite strength on the volume proportion of fiber and the transfer factor is analyzed. Four types of diagrams are constructed for the strength of composites as a function of the volume proportion of fibers and the transfer factor

PEDAGOGICAL CONDITIONS OF SOCIAL-PEDAGOGICAL ADAPTATION OF THE FIRST-YEAR UNIVERSITY STUDENTS UNDER MODERN REALITIES

The article shows the expediency and significance of the work on social-pedagogical adaptation of first-year students of higher educational institutions under the new sociocultural conditions of our time. The search for effective ways of harmonizing the relations (interaction) with the social environment, being the basis for successful socialization and professional training of a future specialist, plays an important role under imperfect organizational and pedagogical support of social-pedagogical adaptation of the first-year students of higher educational institutions. The objective of the research is to theoretically substantiate and experimentally verify the effectiveness of pedagogical conditions of successful social-pedagogical adaptation of the first-year students of higher educational institutions. The research uses theoretical methods (theoretical analysis, generalization and synthesis), empirical methods (observation, questioning, conversation); experimental work; the Student’s criterion and correlation analysis were used as methods of mathematical processing of experimental data. To provide the process of social-pedagogical adaptation of the first-year students, the authors propose the following pedagogical conditions for successful adaptation of the first-year students, allowing, from the viewpoint of integrity of the social-pedagogical adaptation processes, to design and implement the group and individual strategies of the personal trajectories of students’ self-development, and to simultaneously solve the tasks of social, personal and professional development of future specialists: 1) the ability of the university professor to assist a student in their self-cognition, stimulating their personal self-development through motivating their interest in the chosen profession basing on pedagogy of cooperation, creating adequate conditions for expanding the possibility of personally significant and professional qualities of each student; 2) organization of an educational environment aimed at reducing anxiety, apprehension, inner discomfort, where a student realizes themselves as a team member, feels comfortable, which ensures the transformation of the structural components of professionalism as socially important qualities into personal ones; 3) social-pedagogical adaptation of the first-year students becomes an integral part of the university, when the student, without continuous internal and external conflicts, successfully carries out any activity in the educational environment in the context of personality-activity approach, and serves as a means for students to develop adequate self-esteem, advanced self-regulation, and high productivity, which is the basis for the development of activity, independence, and creativity.The authors provide the ways of implementing the revealed pedagogical conditions and the results of the formative experiment, which lead to the following conclusions: active social-pedagogical intervention, timely correction of the educational process, aimed at effective adaptation of the first-year students, through personal interaction basing on pedagogy of cooperation, ensures rapid adaptation of students in a new educational environment, which leads to value attitude to their future profession