241 research outputs found
Enhanced relativistic-electron beam collimation using two consecutive laser pulses
The double laser pulse approach to relativistic electron beam (REB)
collimation has been investigated at the LULI-ELFIE facility. In this scheme,
the magnetic field generated by the first laser-driven REB is used to guide a
second delayed REB. We show how electron beam collimation can be controlled by
properly adjusting laser parameters. By changing the ratio of focus size and
the delay time between the two pulses we found a maximum of electron beam
collimation clearly dependent on the focal spot size ratio of the two laser
pulses and related to the magnetic field dynamics. Cu-K alpha and CTR imaging
diagnostics were implemented to evaluate the collimation effects on the
respectively low energy ( MeV) components of the
REB
Unique challenges accompany thick-shell CdSe/nCdS (n \u3e 10) nanocrystal synthesis
Thick-shell CdSe/nCdS (n \u3e10) nanocrystals were recently reported that show remarkably suppressed fluorescence intermittency or blinking at the single-particle level as well as slow rates of Auger decay. Unfortunately, whereas CdSe/nCdS nanocrystal synthesis is well-developed up to n \u3c 6 CdS monolayers (MLs), reproducible syntheses for n \u3e 10 MLs are less understood. Known procedures sometimes result in homogeneous CdS nucleation instead of heterogeneous, epitaxial CdS nucleation on CdSe, leading to broad and multimodal particle size distributions. Critically, obtained core/shell sizes are often below those desired. This article describes synthetic conditions specific to thick-shell growth (n\u3e 10 and n\u3e 20 MLs) on both small (sub2 nm) and large (\u3e4.5 nm) CdSe cores. We find added secondary amine and low concentration of CdSe cores and molecular precursors give desired core/shell sizes. Amine-induced, partial etching of CdSe cores results in apparent shell-thicknesses slightly beyond those desired, especially for very-thick shells (n \u3e20 MLs). Thermal ripening and fast precursor injection lead to undesired homogeneous CdS nucleation and incomplete shell growth. Core/shells derived from small CdSe (1.9 nm) have longer PL lifetimes and more pronounced blinking at single-particle level compared with those derived from large CdSe (4.7 nm). We expect our new synthetic approach will lead to a larger throughput of these materials, increasing their availability for fundamental studies and applications
Роль юридической ответственности в реализации принципа единства публичной власти в Российской Федерации
The subject. The article presents a comprehensive general theoretical analysis of the institution of legal responsibility and its role, taking into account the consolidation of the new constitutional and legal principle of the unity of the system of public power.The purpose of the research is to confirm or disprove hypothesis that it is necessary to legislate a full-fledged mechanism of legal responsibility of state bodies and local self-government bodies in order to implement the constitutional principle of the unity of public power.Methodology. The formal legal method, the method of comparative legal analysis, dialectical method and systemic approach were used.The main results, scope of application. The authors found the manifestation of dualism in the work of the institution of legal responsibility. It consists in the ability to bear responsibility both to the state, in connection with various offenses, and to the population itself. A brief description of the loss of trust as a basis for the responsibility of officials is given, taking into account contemporary legislation. Directions for the further development of this legal institution are highlighted. The article examines the opinion of the Russian Constitutional Court on the legitimacy of using the loss of trust as a basis for the responsibility of public authorities. The article examines the normative legal acts, which fix the mechanism for the implementation of the principle of maintaining trust in the activities of the authorities on the part of society. For example, in relation to state civil and municipal employees, a prohibition has been established on statements about the activities of authorities and their assessment, if such actions are not included in the list of their official duties. Such a mechanism for maintaining public confidence in the work of government bodies should contribute to strengthening the unity of the public power system. At the same time we can talk about the existing trend towards a decrease in the level of public confidence in the work of authorized bodies exercising public authority. The corruption and bureaucratization of the activities of officials, the expansion of the powers of law enforcement agencies, a decrease in the independence of the political opposition are pointed to among the possible reasons most often. In this regard, the paper proposes expanding the grounds for responsibility when implementing the procedure for recalling an official.Conclusions. It is necessary to consolidate a full-fledged legislative mechanism of legal responsibility of state bodies and local self-government bodies, which will contribute to the implementation and strengthening of the new principle of the unity of public authority.Проводится комплексный общетеоретический анализ института юридической ответственности и его роли с учетом закрепления нового конституционно-правового принципа единства системы публичной власти. По результатам изучения характерных признаков органов публичной власти делается вывод о проявлении дуализма в работе института юридической ответственности. Дается краткая характеристика утраты доверия в качестве основания реализации мер ответственности в отношении должностных лиц и выделяются направления дальнейшего развития этого правового института. Делается вывод о необходимости законодательного закрепления полноценного механизма юридической ответственности государственных органов и органов местного самоуправления, что будет свидетельством реализации и дальнейшего укрепления нового конституционного принципа единства публичной власти
Time-resolved cathodoluminescence of InGaAs/AlGaAs tetrahedral pyramidal quantum structures
An original time resolved cathodoluminescence set up has been used to investigate the optical properties and the carrier transport in quantum structures located in InGaAs/AlGaAs tetrahedral pyramids. An InGaAs quantum dot formed just below the top of the pyramid is connected to four types of low-dimensional barriers: InGaAs quantum wires on the edges of the pyramid, InGaAs quantum wells on the (111)A facets and segregated AlGaAs vertical quantum wire and AlGaAs vertical quantum wells formed at the centre and at the pyramid edges. Experiments were performed at a temperature of 92K, an accelerating voltage of 10kV and a beam probe current of 10pA. The cathodoluminescence spectrum shows five luminescence peaks. Rise and decay times for the different emission wavelengths provide a clear confirmation of the peak attribution (previously done with other techniques) to the different nanostructures grown in a pyramid. Moreover, experimental results suggest a scenario where carriers diffuse from the lateral quantum structures towards the central structures (the InGaAs quantum dot and the segregated AlGaAs vertical quantum wire) via the InGaAs quantum wires on the edges of the pyramid. According to this hypothesis, we have modeled the carrier diffusion along these quantum wires. An ambipolar carrier mobility of 1400cm2/V s allows to obtain a good fit to all temporal dependence
Судебная реформа как инструмент повышения эффективности правовой защищенности личности
The subject. The authors analyze the process and results of 30 years of reforming judicial activity in contemporary Russia, formulate and substantiate the conceptual foundations of promising transformations and specific proposals for continuing the reform, increasing the efficiency of the judicial system and protecting human rights, freedoms and legitimate in-terests.The purpose is to confirm or disprove hypothesis that the Russian judicial reform needs to be adjusted in order to remain the most important factor in building the rule of law and civil society.The research methodology includes the methods of analysis and synthesis, historical, com-parative legal and formal legal methods.The main results, scope of application. The court is one of the most democratic and civilized tools for resolving social conflicts and protecting human interests. Judicial reform is a con-ceptually formed, cardinal and progressive transformation carried out in the historical pe-riod in order to organize the optimal model of the judicial system and achieve maximum efficiency of its functioning to protect the rights and freedoms of the individual, the inter-ests of society and the state. The Russian court was transformed, became the real judiciary power and took its place in the state mechanism during the reform period. The judicial sys-tem was built on new principles, procedural legislation was updated, a number of other measures were taken to improve the status of the court and its role in society. It is necessary to generalize the existing practice and regulate all problematic aspects of the formation of the judicial corps at the legislative level. We need to make this process clear and transpar-ent. Justice as a social and legal value and a significant international goal of sustainable development should be implemented in Russian domestic policy and strategic projects. The strategy and tactics of digital transformation of judicial activity, more active introduction of modern tools in it, while ensuring human rights and freedoms in this process, are particu-larly in demand in the context of the coronavirus pandemic,The conclusion is made that judicial reform is the most important factor in building the rule of law and civil society. However, it has not been completed and its potential for social influence has not been exhausted. Therefore, conceptual foundations and specific proposals for further transformations, increasing the efficiency of the judicial system in order to protect human rights, freedoms and legitimate interests have been formulated and substantiated.Проводится анализ процесса и результатов 30-летнего реформирования судебной деятельности всовременной России. Отмечается, что за период реформы произошла трансформация отечественного суда, который стал подлинной судебной властью и занял свое место в государственном механизме, на новых принципах выстроена судебная система, обновлено процессуальное законодательство, принят ряд других мер по повышению статуса суда и его роли в обществе. Делается вывод, что судебная реформа является важнейшим фактором построения правового государства и гражданского общества, однако она не завершена и ее потенциал социального влияния не исчерпан. Поэтому формулируются и обосноваваются концептуальные основы и конкретные предложения дальнейших преобразований, повышения эффективности судебной системы в целях защиты прав, свобод и законных интересов человека
Реализация юридической ответственности в правосознании и правовой культуре
The subject of the study of the article is the legal foundations of the institution of legal responsibility and the features of its interaction with legal consciousness and legal culture. The goal is to substantiate the need for effective legal regulation of legal liability, taking into account the existing forms of interaction with legal consciousness. The work carried out a comprehensive general theoretical analysis of the institution of legal responsibility and its role in the process of formation and development of the legal consciousness of citizens. The team of authors in the process of studying the place and role of legal liability in the legal system came to the conclusion that there is a relationship between the category under consideration and legal consciousness in the process of implementing legal acts that provide for measures of legal liability. The problem of a low level of legal culture can manifest itself not only in legislative and law enforcement activities. Shortcomings in the implementation of the official interpretation of legal norms and execution of the relevant act in some cases can also cause unlawful consequences, among which are: unlawful prosecution, exemption from liability in violation of established procedures, etc. In the course of the study, a whole set of methods of scientific knowledge was used, among which one can single out: the formal-legal method, the method of comparative legal analysis, systemic, dialectical and others. As a result of the research, it was found that there is a direct connection between the signs of positive responsibility and legal consciousness. In the absence of a high level of legal awareness, which would include both intellectual (views, ideas) and psychological (emotions, feelings) aspects, the implementation of the positive aspect of legal responsibility becomes impossible. It has been proven that positive responsibility, together with legal consciousness, contains volitional and intellectual aspects. The team of authors put forward an opinion according to which the positive responsibility of the individual can be represented as a mental attitude in the form of a sense of duty and the need to fulfill the existing duties to the required extent. Such a sense of duty will be available to the subject only in the absence of a struggle of motives, which is excluded in the developed general legal culture of the individual and society as a whole. Assimilation of the requirements of the law is a prerequisite for the presence of responsible behavior and legal awareness. Based on the results of the study of legal responsibility and legal culture, a conclusion is made about the close interaction of these categories and the need for the legislator to take into account such a connection when exercising his law-making powers. A brief description of positive legal liability with the establishment of its characteristic features is also given. Thanks to the study of the relationship between legal responsibility and legal consciousness, it was revealed that the level of culture will grow if the ideas of social justice, democracy and the rule of law are reflected in law.С целью обоснования необходимости эффективного правового регулирования юридической ответственности с учетом имеющихся форм взаимодействия с правосознанием исследуются правовые основы института юридической ответственности и особенности его взаимодействия с правосознанием и правовой культурой. Проводится комплексный общетеоретический анализ института юридической ответственности и его роли в процессе формирования и развития правосознания граждан. В ходе исследования применялись такие методы научного познания, как формально-юридический, сравнительно-правовой, системный, диалектический и иные. По результатам исследования юридической ответственности и правовой культуры делается вывод о тесном взаимодействии этих категорий и необходимости для законодателя учитывать подобную связь при реализации своих правотворческих полномочий. Также дана краткая характеристика позитивной юридической ответственности во взаимосвязи с правосознанием
Time evolution of stimulated Raman scattering and two-plasmon decay at laser intensities relevant for shock ignition in a hot plasma
Laser–plasma interaction (LPI) at intensities 1015–1016 W cm2 is dominated by parametric instabilities which can be
responsible for a significant amount of non-collisional absorption and generate large fluxes of high-energy nonthermal
electrons. Such a regime is of paramount importance for inertial confinement fusion (ICF) and in particular for the
shock ignition scheme. In this paper we report on an experiment carried out at the Prague Asterix Laser System (PALS)
facility to investigate the extent and time history of stimulated Raman scattering (SRS) and two-plasmon decay (TPD)
instabilities, driven by the interaction of an infrared laser pulse at an intensity 1:2 1016 W cm2 with a 100 mm
scalelength plasma produced from irradiation of a flat plastic target. The laser pulse duration (300 ps) and the high
value of plasma temperature (4 keV) expected from hydrodynamic simulations make these results interesting for a
deeper understanding of LPI in shock ignition conditions. Experimental results show that absolute TPD/SRS, driven at
a quarter of the critical density, and convective SRS, driven at lower plasma densities, are well separated in time, with
absolute instabilities driven at early times of interaction and convective backward SRS emerging at the laser peak and
persisting all over the tail of the pulse. Side-scattering SRS, driven at low plasma densities, is also clearly observed.
Experimental results are compared to fully kinetic large-scale, two-dimensional simulations. Particle-in-cell results,
beyond reproducing the framework delineated by the experimental measurements, reveal the importance of filamentation
instability in ruling the onset of SRS and stimulated Brillouin scattering instabilities and confirm the crucial role of
collisionless absorption in the LPI energy balance
Юридическая аномия в правовой системе: теоретико-методологические основы исследования
A comprehensive general theoretical analysis of legal anomie in the legal system of modern Russian society is carried out. It is said that the theory of state and law currently lacks even the foundations of a holistic concept of legal anomie, but it is precisely this that acts as one of the causes of corruption, terrorism, extremism, legal irresponsibility, a high level of delinquency, massive non-compliance with prohibitions, distancing a significant number of citizens from state power and its rejection. The authors note that anomie to one degree or another always exists. At the same time, the state of social anomie inevitably increases when significant changes occur that affect the social structure and norms. Anomie is an interdisciplinary category that requires appropriate approaches to itself. Social anomie is based on the general interdisciplinary concept of "social deviations", which is studied by a variety of sciences: philosophy, sociology, psychology and many others. A brief description of the theoretical and methodological foundations of the study of social deviations, social anomie and its specific variety - legal anomie is given. For the most complete analysis of legal anomie, it is proposed to use not only systemic (within the category "legal system"), but also comprehensive (within the category "social and legal life") approaches, as well as a number of other methods (in particular, historical, structural and functional and statistical). Legal anomie manifests itself in the form of a decline in the value of law and order, a discrepancy between the goals of society and the means to achieve them offered by the state, the lack of trust between society and public authorities, sustainable legal nihilism. And if in sociology (and some other sciences) there are different directions and concepts for understanding anomie, then in the theory of state and law, a system of scientific knowledge about legal anomie has not yet been formed. Legal anomie in the legal system should be considered comprehensively, in development and comparison, revealing the contradictions and mutual conditionality of its various characteristics, possible pairing, as well as the positive and negative aspects of the existing contradictions between legal anomie and individual elements of the legal system of society. Due to the fact that legal anomie in modern society (following the social and legal life) develops and becomes more complicated, it is concluded that it is necessary to further study it, which will provide: firstly, its more complete knowledge and prediction of consequences, and secondly, the development of effective preventive measures, and, thirdly, the strengthening of counteraction to it.Проводится комплексный общетеоретический анализ юридической аномии в правовой системе современного российского общества. Дается краткая характеристика теоретико-методологических основ исследования социальных отклонений, социальной аномии и ее специфической разновидности – аномии юридической. Для наиболее полного анализа юридической аномии предлагается использовать не только системный (в рамках категории «правовая система»), но и комплексный (в рамках категории «социально-правовая жизнь») подходы, а также ряд иных методов (в частности, исторический, структурно-функциональный, статистический и др.). Делается вывод о необходимости исследования аномии, что обеспечит: во-первых, ее более полное познание и прогнозирование последствий, во-вторых, выработку действенных профилактических мер и, в-третьих, усиление противодействия ей
Measurements of Extended Magnetic Fields in Laser-Solid Interaction
Magnetic fields generated from a laser-foil interaction are measured with
high fidelity using a proton radiography scheme with in situ x-ray fiducials.
In contrast to prior findings under similar experimental conditions, this
technique reveals the self-generated, Biermann-battery fields extend beyond the
edge of the expanding plasma plume to a radius of over 3.5 mm by t=+1.4 ns, a
result not captured in state-of-the-art magneto-hydrodynamics simulations. An
analysis of two mono-energetic proton populations confirms that proton
deflection is dominated by magnetic fields far from the interaction (>2 mm) and
electric fields are insignificant. Comparisons to prior work suggest a new
physics mechanism for the magnetic field generation and transport in
laser-solid interactions.Comment: 9 pages, 8 figure
Кинетика пиролиза древесной биомассы в изотермических условиях
The paper discusses the results of a kinetic study of the pyrolysis of woody biomass (ordinary oak wood – Quercus robur) under static conditions at temperatures of 673, 773 and 873 K. In experiments, biomass samples weighing about 1.4 g were kept in a heating furnace for a certain period, after which their residual weight was measured and the degree of decomposition achieved was determined. A total of 7 series of experiments were performed: two series each at temperatures of 673 and 873 K and three series at a temperature of 773 K. The obtained results were analyzed in the framework of a single-stage chemical reaction (one-step global model), leading to a loss of the initial mass. It was established that from the phenomenological point of view, the pyrolysis of woody biomass under experimental conditions corresponds to the sigmoidal reaction model by Avarami–Erofeev with an exponent n ranging from 0.508 to 0.985. The use of the results of the first series of experiments led to an activation energy value of 57.2 kJ/mol and a pre-exponential factor value of 38 s–1. The other series of experiments gave an activation energy value of 64.9 kJ/mol and a preexponential factor value of 130 s–1. It is shown that the use of these values of the activation energy and the preexponential factor leads to agreement of the calculated values of the degree of decomposition of the studied biomass samples with the experimental ones in the range of values of the degree of decomposition from 0 to 1. The data presented in this work contribute to a more complete understanding of the kinetics of pyrolysis of biomass, which is necessary for the development of effective equipment for the thermochemical processing of vegetable raw materials.Обсуждаются результаты кинетического исследования пиролиза древесной биомассы (древесина дуба обыкновенного – Quercus robur) в статических условиях при температурах 673, 773 и 873 К. В опытах образцы массой порядка 1,4 г выдерживались в нагревательной печи на протяжении некоторого промежутка времени, после чего измерялась их остаточная масса и определялась достигнутая степень разложения. Всего выполнено семь серий опытов: по две серии при температурах 673 и 873 К и три серии при температуре 773 К. Полученные результаты анализировались в рамках одностадийной химической реакции, приводящей к потере исходной массы. Установлено, что с феноменологической точки зрения пиролиз древесной биомассы в условиях опытов соответствует сигмоидальной реакционной модели Аврами–Ерофеева с показателем степени n, изменяющимся в пределах от 0,508 до 0,985. Анализ результатов первых серий опытов привел к значению энергии активации, равному 57,2 кДж/моль, и значению предэкспоненциального фактора, равному 38 с–1. Другие серии опытов дали значение энергии активации, равное 64,9 кДж/моль, и значение предэкспоненциального фактора, равное 130 с–1. Показано, что использование этих значений энергии активации и предэкспоненциального фактора приводит к согласию расчетных значений степени разложения изученных образцов биомассы с экспериментальными в интервале значений степени разложения от 0 до 1. Представленные в работе данные способствуют более полному пониманию кинетики пиролиза биомассы, что необходимо для разработки эффективного оборудования для термохимической переработки растительного сырья
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