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Погрешности результатов количественных газохроматографических определений способами, предполагающими использование абсолютных площадей хроматографических пиков, в том числе внешнего стандарта, «чувствительны» к воспроизводимости дозирования проб. Эффективным приемом компенсации таких погрешностей является введение в анализируемые образцы дополнительных стандартов и замена абсолютных площадей пиков их отношениями к площадям пиков стандартов. Важно, что в качестве дополнительных стандартов можно использовать любые компоненты образцов, в том числе входящие в их состав растворители. В модифицированном варианте количественного анализа способом внешнего стандарта растворитель можно использовать, даже если его пики регистрируются в «усеченном» виде в результате ограничения выходных сигналов усилителя. Использование относительных площадей пиков не требует никаких дополнительных операций с образцами, кроме регистрации площадей пиков растворителя. Сравнение обычного и модифицированного вариантов способа внешнего стандарта показывает, что замена абсолютных значений площадей пиков отношениями площадей пиков целевого аналита и растворителя не влияет на характеристики точности определений по критерию «введено-найдено», но уменьшает случайную составляющую погрешности определений в 2-3 раза. Обсуждается проблема повышения достоверности подобных статистических оценок, для чего представляется целесообразным изменение «дизайна» экспериментальных операций. Вместо последовательных анализов однотипных образцов предпочтительнее использовать параллельные определения, что можно достичь, например, при выполнении практических работ студентами. Uncertainties of the results of quantitative determinations in gas chromatography using the methods based on the absolute peak areas (including the external standard method) are rather “sensitive” to the reproducibility of injections. The effective way to compensate for such errors is to introduce the additional standards into the samples, followed by replacing the absolute peak areas by their ratios to peak areas of the standards. It is important to underline that any constituents of the samples can be used as additional standards, including the solvents. Solvents can be used for these purposes even if the heights of their peaks are restricted when the analytical signals exceed the amplifier limits. Using the relative peak areas does not require any extra sample processing besides the registration of peak areas for solvents. Comparing the commonly known and modified methods of external standard demonstrates that using the relative peak areas instead of the absolute ones does not influence the overall precision of determinations (according to the criterion “introduced-determined”) but improve the reproducibility by 2-3 times. The problem of increasing the reliability of such statistical evaluations of results is discussed and to solve it, it is proposed to change the “design” of the experiments. Instead of series of successive analyses of similar origin samples, the use of parallel determinations is preferable. This can be realized, for example, during the fulfillment of student’s practical works. Студенческая практическая работа, результаты которой составили предмет настоящего сообщения, выполнена с использованием оборудования Ресурсного Центра «Методы анализа состава вещества» Санкт-Петербургского государственного университета. Авторы благодарят сотрудников Центра за содействие. The students’ work, the results of which are discussed in this paper, was carried out using the equipment of the “Methods of analysis of substance’s composition” Resource Centre at St. Petersburg State University. The authors are grateful to the staff of this Center for their assistance.

A two-component organosilicon composition was developed based on a solution of linear ladder organosilicon block copolymers containing linear polyorganosiloxane and ladder phenylsilsesquioxane units in an organic solvent and a curing agent, vinyl-tris-(acetoximo)silane. The composition can be used for the preparation of heat-resistant flexible and strong electroinsulating corrosion-passive coatings that serve to protect active components of micro- and radioelectronic products from effects of severe climatic factors.

Two iridium [Ir(N^C)

To explain the catalytic properties inherent to a number of coatings formed by the method of plasma-electrolytic oxidation (PEO), a series of Ni- and/or Cu-containing coatings on aluminum were investigated by X-ray photoelectron spectroscopy (XPS). It was determined that the main components of the surface layers of these coatings are a variety of oxide structures of the base and electrolyte elements – oxides of aluminum, nickel, copper, and more complicated composite structures. In this chapter, our experimental results are introduced.

The regaining of Lithuania’s independence has broadly opened its borders to emigration of compatriots. Various reasons make Lithuanians leave their homeland and look for happiness abroad. Recently, more and more people are discussing about Lithuanian families’ immigration to Scandinavian countries, and in particular to Norway. Therefore, the problem of this article is based on the notion, that the families of Lithuanian emigrants and their children who are in a foreign country, in a foreign social environment, must adapt and integrate. However the problems they face require not only help of family members and other relatives, but also state intervention and assistance which is not is always effective or insufficiently implemented to provide full benefits to immigrants. On the other hand, it can be assumed that immigrants are not sufficiently interested to get the benefits from the assistance and services that those institutions can provide. Therefore, this study examined the main problems of the integration of Lithuanian immigrant children in Norway and what actions of Lithuanian immigrants are leading to successful integration of their children. Experiences of the study of the integration of Lithuanian emigrant families and children in Norway revealed that at the beginning of integration, despite immigration positivity’s (a better education system, better perspectives for the future of children), problems such as language barriers, negative attitudes towards them, ignorance of the functioning of the social system are encountered. These problems could be avoided by the need to learn the Norwegian language quickly, using relatives, friends and neighbors and local communities, actively communicating and cooperating with educational institutions, participation in public life and the support of certain state social institutions. Keywords: emigration / immigration, immigrants, integration problems, help for immigrants.

In this study the thermodynamic properties of the dodecahydro-closo-dodecaborate anion B12H122− and its fluorinated derivatives, namely, B12Hx(CF3)12−x2− (x = 9–12), have been calculated at the B3LYP-D3/6-311++G∗∗ level of theory. The calculated gas-phase heats of formation indicate the high thermodynamic stability of B12H122− anion complexes in which the hydrogen atoms are substituted by trifluoromethyl groups. Herewith, this stability increases with the increasing number of CF3 groups. According to Gibbs energy calculations, the formation of the B12Hx(CF3)12−x2− anion complex with the maximum degree of substitution (x = 9) is much more favorable than the formation of the initial anion complex B12H122− (x = 12). Therefore, it can be concluded that the introduction of fluorinated groups to the exo-environment of B12H122− has a thermodynamically stabilizing effect.

Статья посвящена вопросам общекультурного, личностного и познавательного развития младших школьников на уроках литературного чтения посредством использования элементов технологии проблемного обучения. Обобщены теоретические аспекты проблемного обучения, перечислены этапы проблемного обучения. Обосновывается необходимость использования на уроках литературного чтения приемов и средств проблемного обучения. Рассматриваются аспекты организации проблемных ситуаций как особого вида умственного взаимодействия педагога и обучающихся, при котором требуется обнаружение или открытие новых, ранее неизвестных младшим школьникам литературоведческих знаний или способов деятельности. Представлены основные способы создания проблемных ситуаций, способствующие развитию у младших школьников навыков познавательной активности, помогающие формированию у них умения творчески решать учебные задачи, стимулирующие интерес к чтению произведений художественной литературы и фольклора, направленные на формирование читательской компетентности младших школьников. The article is devoted to the issues of general cultural, personal and cognitive development of junior schoolchildren at literary reading lessons through the use of elements of technology of problem training. The theoretical aspects of problem training are generalized, the stages of problem training are listed. The necessity of using methods and means of problem-based training for literary reading lessons is substantiated. The aspects of the organization of problem situations as a special kind of mental interaction between the teacher and students are considered, in which the discovery or discovery of new literary knowledge or methods of activity unknown to younger students is required. The main ways of creating problem situations that contribute to the development of skills of cognitive activity in younger schoolchildren, helping them to form their ability to creatively solve learning problems that stimulate interest in reading works of fiction and folklore aimed at forming the reader competence of junior schoolchildren are presented.

Lietuvos nepriklausomybės atkūrimas 1990 m. atvėrė sienas gyventojų emigracijai. Įvairios priežastys priverčia lietuvius palikti tėvynę ir ieškoti laimės svetur. Šiame straipsnyje pateikiamos į Norvegiją išvykusių lietuvių šeimų, ypač jų vaikų, integracijos problemos svetimoje šalyje. Mokslinės literatūros analizė atskleidė įvairias žmonių migracijos priežastis (geresnės materialinės sąlygos, profesijos prestižas, karjeros galimybės) ir problemas (kalbos nemokėjimas, įstatymų nežinojimas, psichologinis diskomfortas), su kuriomis susiduria į emigracijos šalis atvykę imigrantai. Mūsų straipsnyje šie terminai (emigrantai / imigrantai) naudojami kaip sinonimai (lietuviai Norvegijoje – imigrantai, lietuviai, išvykę iš Lietuvos – emigrantai). Pusiau struktūruoto interviu metodu ištirtos lietuvių emigrantų šeimų ir vaikų integravimosi į Norvegijos visuomenę patirtys atskleidė, jog integracijos pradžioje susidurta su kalbos barjeru, neigiamu požiūriu į juos, nežinojimu, kaip veikia socialinė sistema. Šių problemų galima būtų išvengti, pasistengus greitai išmokti norvegų kalbą, pasinaudojus vietinių bendruomenių pagalba, aktyviai bendraujant ir bendradarbiaujant su ugdymo įstaigomis, dalyvaujant visuomeniniame gyvenime ir priimant tam tikrų valstybės socialinės sistemos institucijų pagalbą. The regaining of Lithuania’s independence has broadly opened its borders to emigration of compatriots. Various reasons make Lithuanians leave their homeland and look for happiness abroad. Recently, more and more people are discussing about Lithuanian families’ immigration to Scandinavian countries, and in particular to Norway. Therefore, the problem of this article is based on the notion, that the families of Lithuanian emigrants and their children who are in a foreign country, in a foreign social environment, must adapt and integrate. However the problems they face require not only help of family members and other relatives, but also state intervention and assistance which is not is always effective or insufficiently implemented to provide full benefits to immigrants. On the other hand, it can be assumed that immigrants are not sufficiently interested to get the benefits from the assistance and services that those institutions can provide. Therefore, this study examined the main problems of the integration of Lithuanian immigrant children in Norway and what actions of Lithuanian immigrants are leading to successful integration of their children. Experiences of the study of the integration of Lithuanian emigrant families and children in Norway revealed that at the beginning of integration, despite immigration positivity’s (a better education system, better perspectives for the future of children), problems such as language barriers, negative attitudes towards them, ignorance of the functioning of the social system are encountered. These problems could be avoided by the need to learn the Norwegian language quickly, using relatives, friends and neighbors and local communities, actively communicating and cooperating with educational institutions, participation in public life and the support of certain state social institutions.

Copper (II) oxide clusters (CuO)nwith n = 1 – 4, 6 have been calculated by DFT method with the exchange-correlation functional B3LYP. The structural, energy and electronic properties have been studied. Much attention was given to the interaction between CO and active centers of the clusters. The most probable orientation of CO on the metal oxide surface has been determined and the stability of clusters has been evaluated.

The article contains summarized results of the research into developed software programme capable of processing findings of hydraulic experiments held at pressure pipelines (protective coatings). The authors describe the algorithm of the analysis procedure, sequential analysis, mathematical and hydro-mechanical modeling of the process of transformation of hydraulic values. The authors provide their concept of the dialog box and description of input and output information, as well as functions of the software programme at intermediate stages of the hydraulic analysis. Basic input information supplied into the hydraulic analysis software programme includes the pipeline, its inner diameter, length, and acceptable roughness error.Whenever a user presses the “display result” button, interim information is displayed on the screen and, if necessary, a set of output information is provided in the form of tables and graphs. The choice for the optimal solution is made on the basis of the minimum margin of error between experimental and analytical values of the pipe roughness.The findings may be useful to researchers involved in the study of hydraulic characteristics of pipelines made of various materials and to designers and builders engaged in renovation of sections of pipelines.Проведено исследование по созданию автоматизированной программы комплексной обработки результатов гидравлических экспериментов, проводимых на напорных трубопроводах (защитных покрытиях). Описан алгоритм процесса расчета, последовательного анализа, математического и гидромеханического моделирования трансформации гидравлических показателей, определяемых в период проведения базового эксперимента с трубой соответствующего диаметра и при моделировании перехода от одного диаметра трубопровода к другим. Представлен общий вид диалогового окна с описанием входной и выходной информации, а также функций программы на промежуточных этапах расчета гидравлических показателей. Определен и исследован механизм выбора оптимального решения по определению гидравлических показателей на основе сопоставления величин погрешности измерений реальной (по профилометру) величины шероховатости и опытного ее значения, полученного в результате эксперимента.

The geometric, energetic, spectral and electronic properties of the most stable isomers of B12Hx(CF3)12-X2− anion complex with x = 9 – 12 have been studied using Density Functional Theory (B3LYP/6-311++G**). It was shown that these isomers are characterized by the preference to form the most symmetric structures with uniformly distributed charge densities. However, when replacing a hydrogen atom with fluoromethyl group, an inductive effect occurs. Blue shifts in the IR spectrum compared to the vibrations of the free CF3 molecule are in the range of 2 – 69 cm−1 and points to the stability of B12Hx(CF3)12-x2− anions.

The geometric, energetic, spectral and electronic properties of various isomers of B12Hх(NF2)12-х 2− anion complex with x = 9 − 12 have been studied using Density Functional Theory (B3LYP/6-311++G**). It was shown that the most stable isomers are characterized by the preference to form the most symmetric structures with uniformly distributed charge densities. However, when replacing a hydrogen atom with difluoramino group, an inductive effect occurs. NF2 group pulls a part of electron density that leads to the polarization of the boron core. Blue shifts in the IR spectrum compared to the vibrations of the free radical NF2 ranging from 5 to 69 cm−1 for the most stable isomers with the minimum total energy are characteristic and points to the stability of B12Hх(NF2)12-х 2− anions. The obtained results broaden the idea of aromaticity of B12H12 2− anion and will be useful in synthesis of new B12H12 2− derivatives.