Influence of the scattering particle shape on the SiO2 silicate feature

Silicate dust particles are part of many astronomical objects such as comets and circumstellar disks. In a spectrum, silicates exhibit a number of characteristic silicate emission features. To study these features, Mie’s theory is usually used. This theory assumes that the scattering object is an ideal sphere. In this work, we investigated the contribution of non-spherical quartz particles (SiO2) to these features. We studied the influence of the deviation from sphericity on the 10-micron silicate feature of quartz. It is shown that the deviation from sphericity has a significant effect on both the scattered light intensity and the scattering factor Qsca, and this effect increases with increasing scattering particle size. The main peculiarities of the 10-micron silicate feature have been studied for both prolate and oblate spheroids.

Prediction Model for Compressive Strength of Porous Concrete with Low-Grade Recycled Aggregate

As the first batch of products after the resource utilization of construction and demolition waste, low-grade recycled aggregate (RA) has not been fully utilized, which hinders the development of the comprehensive recycling industry of construction waste. Therefore, this paper studies the mechanical properties of porous concrete (POC) with low-grade RA. An improved relationship between porosity and compressive strength of brittle, porous materials is used to express the compressive strength of POC with recycled aggregate (RPOC), and the prediction for compressive strength of porous concrete with low-grade RA is constructed by analyzing the mechanism of compressive damage. The results show: the compressive strength of porous concrete decreases with the addition of low-grade recycled aggregate, but the effect is not obvious when the replacement rate is less than 25%. The error range of the relationship between porosity and compressive strength of RPOC is basically within 15% after improvement. The prediction model for compressive strength based on the ideal sphere model of aggregate can accurately reflect the compressive strength of porous concrete with low-grade RA. The results of this study can provide a reference for the staff to learn about the functional characteristics of recycled products in advance and provide security for the actual project.

Mystery in the poetics of romantic tragedy genre (“The Spaniards” by Mikhail Lermontov)

This paper focuses on the role of the poetics of mystery in the formation of the romantic trag-edy genre. “The Spaniards” by Mikhail Lermontov is considered as a characteristic example of this genre, manifesting “melodramatization” of tragedy and tendency towards genre-generic synthesis. The action of “The Spaniards” is based on events related to the sphere of the mysterious, which are exceptional in life and common in melodrama. Central to the plot is the motif of the loss of a child. The secret of Fernando’s birth and “ignobility” form the con-flict and organize two storylines (love and family) and two (everyday life – melodramatic, and existential – tragic) levels of conflict. Mystery also plays an important role in revealing the inner world and expressing the romantic ideal of the hero. The ability to comprehend the mysterious, to pass beyond human experience and logic is not only the motivation of his ac-tions, but it also connects the hero with the ideal sphere. The study examines how the charac-ters’ anticipation of the “terrible” motivates their moral choices. Analyzing the interaction of lyrical motifs, the author suggests the motif of mystery as important for implementing the main (tragic) conflict, unlike melodrama, where the functions of mystery are plot-forming, stimulating the spectator’s interest and maximizing the dramatic tension. Mystery in the plot and the lyrical concept of the tragedy contributes to the understanding of the essence of the romantic conflict, has a suggestive impact on the audience, and deepens the psychologism.

Event as Object: Towards a Flat-Event Theory

In the article, the author offers an original version of the solution to the problem of the atomicity of social events. The relevance of the topic is due to the fact that it is indivisibility that makes it possible to distinguish an event from other social phenomena/processes. From the author’s point of view, the event must have a certain duration, which is atomic. As the first step, the author, relying on a wide range of sources that include the views of various theorists, considers the problem of the indivisibility of social events in the current theory of events. The author notes that logical-semantic interpretations of the indivisibility of events have become more widespread than the statement of ontological atomicity. Furthermore, the author dwells, in detail, on the interpretation of atomicity by observation. Analyzing the views of D. Davidson, A. F. Filippov, and others, the author proves that in the case of atomicity, by observation: (1) the criteria for this atomicity are rather blurred; (2) the event is a consequence not only of the observer’s figure, but also of his system of distinction and motives; (3) the complexity may be related to the spatial factor; and 4) the event itself is confused with the fact. The author also believes that limiting social events only to what is available to the human eye is not in line with modern trends. Additionally, the author shows the productivity of understanding the event as an object. In contrast to the participants in discussions aimed at distinguishing an event and an object, the author uses object conceptualization offered by object-oriented ontology. Events, which as objects are capable of change while retaining their indivisibility and stability, can be associated not only with the material but also with the ideal sphere, and have a system of distinctions. The proposed scheme allows us to assert the impossibility of negative events, gives a reason not only to talk about the atomicity of the event but to also emphasize the ontological foundations of this atomicity, and also offers the possibility of thinking about the social beyond the observed.

Prediction Method for Hydraulic Conductivity considering the Effect of Sizes of Ellipsoid Soil Particles from the Microscopic Perspective

In the existing research studies of hydraulic conductivity, most of them assume that soil consists of spheroidal particles and the value of hydraulic conductivity can be designated by the particle size. In the actual soil layers, the shape of soil particles is mostly ellipsoid or rod-like rather than ideal sphere. Therefore, the prediction of soil permeability using current method often deviates from the actual situation and cannot capture the anisotropy nature of soil without consideration of the effect of the axis size of soil particles in two different directions. To solve this problem, a new theoretical model with three different soil particle arrangements is introduced to derive a new hydraulic conductivity-particle size relationship considering the size difference in two directions. This model, from a microscopic perspective, divides pores into numerous pore units and obtains hydraulic conductivity of each tube unit, eventually predicting the permeability of soil layer based on an equivalence principle. The proposed equation is validated in comparison with experimental data from the existing literature and is proved to have a satisfied accuracy to predict hydraulic conductivity for a wide range of soils, from bentonite-silt mixed soils to sandy soils. The proposed model provides a new perspective for accurately predicting the hydraulic conductivity.

The International Association of Geodesy: from an ideal sphere to an irregular body subjected to global change

The history of geodesy can be traced back to Thales of Miletus (∼600 BC), who developed the concept of geometry, i.e. the measurement of the Earth. Eratosthenes (276–195 BC) recognized the Earth as a sphere and determined its radius. In the 18th century, Isaac Newton postulated an ellipsoidal figure due to the Earth's rotation, and the French Academy of Sciences organized two expeditions to Lapland and the Viceroyalty of Peru to determine the different curvatures of the Earth at the pole and the Equator. The Prussian General Johann Jacob Baeyer (1794–1885) initiated the international arc measurement to observe the irregular figure of the Earth given by an equipotential surface of the gravity field. This led to the foundation of the International Geodetic Association, which was transferred in 1919 to the Section of Geodesy of the International Union of Geodesy and Geophysics. This paper presents the activities from 1919 to 2019, characterized by a continuous broadening from geometric to gravimetric observations, from exclusive solid Earth parameters to atmospheric and hydrospheric effects, and from static to dynamic models. At present, we identify geodesy as the discipline of quantifying global change by geodetic measurements.

Some Relations between Ethics, Aesthetics and Politics in Contemporary Art in Times of Crisis

The inclusion of ethics and politics into artistic creation process is for many contemporary creators/artists an essential motivation while they consciously act in an aesthetic space polluted with the realities of a world in crisis. Art, which produces visible and sensible forms, can reveal aesthetic ideas and fundaments through aesthetic objects: drawing, video-installing or poem/poetry. And artists can make someone feel with their creations—whether these are beautiful, sublime, tragic, or ironic—ethical contentions violated by human action or the exertion/exercise of political power. Works of art that are not only guided by the categories signed by beauty, because in artistic languages, violence and suffering also make/create form. And times of crisis are the ideal sphere/dimension for an art that gives a vivid way of seeing/watching the uncertainty, the perversion, the terrible. In bringing these philosophical—ethical, aesthetic and political—topics, I do it from an approach that departs form artistic creations and curatorial research. I try to penetrate the narrow thread between an ethical topic and the plastic form in which it incarnates/embodies itself, or between a political action and the aesthetic structure of language as a creative, expressive consequence.

Electrostatic Field Calculations for Liquid Nitrogen Gaps Assuming a Decisive Field Factor

Volume effect on breakdown voltage is well known in high voltage engineering. The breakdown voltage behavior of liquid nitrogen depending on a high field volume had been quantitatively described for gap lengths up to 20 mm. Breakdown curves for longer gap lengths up to 96 mm derived from measurements with a facility “Fatelini 2” show oscillations and partly low withstand voltages. Electrostatic field calculation for such long gaps shows remarkable high field volume differences between a model for ideal sphere and models including fixation rods. Calculation for the used setup does not show monotonically increasing high field volume depending on gap length but a maximum around 60 mm which can explain the special breakdown behavior in a “mid range” gap length. Further high field calculations were done for not yet used setups in order to make considerations, e.g. for the influence of cryostat material or diameter.