scholarly journals Refinement of the relationship between effective radii and ionization energies of alkali metal atoms

2020 ◽  
Vol 64 (10) ◽  
pp. 7-13
Author(s):  
Victor M. Yakovlev ◽  
◽  
Ivan K. Garkushin ◽  
Alexander V. Burchakov ◽  
◽  
...  
Keyword(s):  
Alkali Metals ◽  
Effective Interaction ◽  
Ionization Energies ◽  
Quantum Numbers ◽  
Analytical Formulas ◽  
Effective Principal ◽  
Simple Power Function ◽  
Semi Empirical ◽  
The Relationship ◽  
Atomic Radii

One of the key explanations for the peculiarities of the change in the first ionization energies (IE Ei1) of the elements of the periodic table is based on the postulation of an unambiguous relationship between Ei1 and atomic radii (rat). Due to the certain conventionality of the rat parameters, they do not belong to the category of attributive atomic characteristics. Usually they are found either by implementing various kinds of theoretical or semi-empirical calculation schemes, or by using experimental data on Ei1 for the corresponding approximations. As follows from the literature data, the known values of rat, even in the case of "quasi-hydrogen-like" alkali metals (AM), –relatively simple manyelectron systems – are characterized, as a rule, by a significant scatter. In addition, the canonical analytical formulas describing rаt within the framework of a hydrogen-like model with two effective interaction parameters (according to Slater) do not ultimately lead to adequate results in this set of elements. In this work, to correct the relationship rat = f (Еi1) related to the properties of the aggregate of alkaline elements, the publication of the effective Slater radii (reff) and Weber-Cromer orbital radii (rorb), and some results of later data are used. The effective principal quantum numbers n* for each of the AM (except for Li, for which it is assumed that n*=n=2) are estimated on the basis of the values of Ei1. A further step, by introducing n*, made it possible to use the criterion for optimizing the value of the effective radius r* and to correct the formula that determines its relationship with Ei1 in the form of a simple power function. At the same time, the radii Li, Na, and Fr have been refined towards some underestimation, compared with rorb. Arguments are presented in favor of the reliability of the proposed approach. It is shown that the obtained estimates of r* correlate better with the amplitudes of the solution of the wave equation covering all AMs than the known corresponding values of rorb and reff.

A study on the estimations of (n, t) reaction cross-sections at 14.5 MeV by using artificial neural network

2021 ◽  
pp. 2150168
Author(s):  
Hasan Özdoğan ◽  
Yiğit Ali Üncü ◽  
Mert Şekerci ◽  
Abdullah Kaplan
Keyword(s):  
Neural Network ◽  
Artificial Neural Network ◽  
Cross Sections ◽  
Reaction Cross ◽  
Forward Algorithm ◽  
Network Algorithms ◽  
Analytical Formulas ◽  
Artificial Neural ◽  
Semi Empirical ◽  
Reaction Cross Sections

In this paper, calculations of the [Formula: see text] reaction cross-sections at 14.5 MeV have been presented by utilizing artificial neural network algorithms (ANNs). The systematics are based on the account for the non-equilibrium reaction mechanism and the corresponding analytical formulas of the pre-equilibrium exciton model. Experimental results, obtained from the EXFOR database, have been used to train the ANN with the Levenberg–Marquardt (LM) algorithm which is a feed-forward algorithm and is considered one of the well-known and most effective methods in neural networks. The Regression [Formula: see text] values for the ANN estimation have been determined as 0.9998, 0.9927 and 0.9895 for training, testing and for all process. The [Formula: see text] reaction cross-sections have been reproduced with the TALYS 1.95 and the EMPIRE 3.2 codes. In summary, it has been demonstrated that the ANN algorithms can be used to calculate the [Formula: see text] reaction cross-section with the semi-empirical systematics.

Principals’ Perceptions of Transformed School Counselors

2019 ◽  
Vol 103 (2) ◽  
pp. 139-157
Author(s):  
Ashley Lawrence ◽  
Carolyn Stone
Keyword(s):  
School Counselors ◽  
School Principals ◽  
Hiring Practices ◽  
Leadership Qualities ◽  
Factors Affecting ◽  
Counselor Educator ◽  
Effective Principal ◽  
The Relationship ◽  
Principals Perceptions ◽  
Perceptions Of School

This study investigated the relationship between the Transformed School Counseling (TSC) initiative counselor educator programs, the perceptions of school principals hiring TSC-prepared school counselors, and factors affecting principal’s hiring practices. Results indicated that principal’s value TSC candidates because they: (a) have effective principal-counselor relationships that positively affect students, (b) exemplify leadership qualities, (c) align their work with the mission of the school, (d) have strong communication skills, and (e) do not require additional training.

scholarly journals REACTIONS OF HYDROXIBENZOIC ACIDS WITH 2-AMIDINOPROPAN-2-PEROXYL IN ACID MEDIA

2020 ◽  
pp. 81-95
Author(s):  
Александр Владимирович Белый ◽  
Наталья Ивановна Белая ◽  
Виктор Сергеевич Дорошкевич
Keyword(s):  
Antiradical Activity ◽  
Aqueous Media ◽  
Peroxyl Radicals ◽  
Chemiluminescence Method ◽  
Acid Media ◽  
Antiradical Properties ◽  
Hydroxybenzoic Acids ◽  
Semi Empirical ◽  
The Relationship ◽  
Factor Equation

Методом хемилюминесценции определена реакционная способность гидроксибензойных кислот при взаимодействии с 2-амидинопропан-2-пероксильными радикалами, генерированными при термическом распаде азоинициатора 2,2ʹ-азобис(2-амидинопропан) дигидрохлорида в фосфатном буфере при рН=2. Установлена зависимость между антирадикальной активностью и молекулярными дескрипторами кислот, связанными с механизмом их антирадикального действия, в виде полуэмпирического линейного однофакторного уравнения. Полученная связь «дескриптор-активность» может быть основой для прогнозирования антирадикальных свойств фенолокислот и подобных им структур в водных средах. The reactivity of hydroxybenzoic acids in the reaction with 2-amidinopropane-2-peroxyl radicals generated by thermal decomposition of azoinitiator 2,2ʹ-azobis(2-amidinopropane)dihydrochloride in phosphate buffer at pH=2 was determined using chemiluminescence method. The relationship between the molecular acid descriptors, associated with the mechanism of their antiradical action, and antiradical activity in the form of a semi-empirical linear one-factor equation was established. The obtained «descriptor-activity» relationship can be used as a basis for predicting the antiradical properties of phenolic acids and similar structures in aqueous media.

scholarly journals МОДЕЛЮВАННЯ ВЗАЄМОДІЇ КРИЛЕВОГО ПРОФІЛЮ З ДОЩОВИМ ПОТОКОМ

2020 ◽  
pp. 36-41
Author(s):  
Сергей Евгеньевич Aгеев ◽  
Юрий Петрович Миляев
Keyword(s):  
Water Film ◽  
Aerodynamic Characteristics ◽  
Negative Consequences ◽  
Wing Profile ◽  
Air Interface ◽  
Adopted Model ◽  
Semi Empirical ◽  
Relationship Of ◽  
Surface Tension Forces ◽  
The Relationship

The subject of the study is the analysis of the multilateral impact of rainfall on the flight of a modern aircraft. When considering various factors of this impact, it was found that the main negative consequences of the interaction of the aircraft with the rain flow are the formation of a thin layer of water on its surface, which under the influence of drops and surface tension forces changes the configuration of the wing profile, causing loss of load-bearing properties and an increase in frontal aircraft resistance. The influence of rain flowing around the bearing surfaces can be reduced to taking into account changes in the characteristics of the surface and the flow of the airflow. The goal is to develop a model for the interaction of modern wing profiles with rain flow. The task is to determine the amount of water deposited on the surface of the wing profile, calculate the parameters of the water film formed on its surface, and as a result of this, change the tangential stress at the liquid-air interface. The semi-empirical calculation method used reveals a significant dependence of the amount of precipitated rain water on the surface of modern wing profiles on their geometry and the conditions of interaction with the stream of raindrops. The result of this work is the resulting model, which allows you to simulate the flow conditions around the wing profile in the rain stream and evaluate the relationship of rain intensity with the parameters of the water film that forms on the profile. Conclusions. An analysis of the features of the rain film flow over the surface of the wing profile and its effect on the parameters of the boundary layer shows the negative nature of the effect of rainfall on the aerodynamics of the aircraft. The results obtained allow us to judge the reliability of using the adopted model to calculate the effect of rain on the aerodynamic characteristics of wing profiles, and the possibility of using the results to determine the dependence of the aerodynamic characteristics of wing profiles on the conditions of rainfall molasses.

scholarly journals Intentional mindset towards robots – open questions and methodological challenges

2019 ◽  
Author(s):  
Elef Schellen ◽  
Agnieszka Wykowska
Keyword(s):  
Social Cognitive ◽  
Effective Interaction ◽  
Critical Evaluation ◽  
Humanoid Robots ◽  
Mental States ◽  
Human Robot Interaction ◽  
Intentional Stance ◽  
Cognitive Mechanisms ◽  
Open Questions ◽  
The Relationship

Natural and effective interaction with humanoid robots should involve social cognitive mechanisms of the human brain that normally facilitate social interaction between humans. Recent research has indicated that the presence and efficiency of these mechanisms in human-robot interaction (HRI) might be contingent on the adoption of a set of attitudes, mindsets and beliefs concerning the robot’s inner machinery. Current research is investigating the factors that influence these mindsets, and how they affect HRI. This review focuses on a specific mindset, namely the “intentional mindset” in which intentionality is attributed to another agent. More specifically, we focus on the concept of adopting the intentional stance towards robots, i.e., the tendency to predict and explain the robots’ behavior with reference to mental states. We discuss the relationship between adoption of intentional stance and lower-level mechanisms of social cognition, and we provide a critical evaluation of research methods currently employed in this field, highlighting common pitfalls in the measurement of attitudes and mindsets.

scholarly journals Theoretical Atomic Radii of Elements (H-Cm): A Non-Relativistic Study with Gaussian Basis Set Using HF, Post-HF and DFT Methods

2021 ◽  
Author(s):  
Krishnamohan Prasanna ◽  
Sooraj Sunil ◽  
Ajith Kumar ◽  
Jamesh Joseph
Keyword(s):  
Electron Correlation ◽  
Van Der Waals ◽  
Basis Set ◽  
Dft Methods ◽  
Ionization Energies ◽  
Spin Polarized ◽  
Gaussian Basis Set ◽  
Van Der Waals Radii ◽  
Atomic Radii ◽  
Good Agreement

<div><p>We calculated the most probable radius of an atom for elements from H to Cm. The calculations were carried out by using non-relativistic, spin polarized, HF, MP2 and DFT methods with all electron Gaussian basis set<i>. </i>Periodicity of atomic radii was correlated with the experimental first ionization energies. This non-relativistic atomic radii were also compared with other theoretical atomic radii. With respect to the Dirac-Slater data, our values were in good agreement with the elements up to Sn. Relationship with van der Waals radii of noble gases was discussed. Anomalous properties of Gd and Pd were examined. Linearity of lanthanide contraction of elements with <i>4f </i>electrons is illustrated. This linearity is found independent of the extent of electron correlation. S.I. give data of calculated radii and other correlated studies (with ionization energies, another theoretical radii etc.)</p></div>

scholarly journals Organization of effective interaction between the general contractor and subcontractors using the tools of calendar network planning of construction

2021 ◽  
Vol 258 ◽  
pp. 09033
Author(s):  
Alexander Rudko ◽  
Marat Kuzhin
Keyword(s):  
Russian Federation ◽  
Effective Interaction ◽  
Advantages And Disadvantages ◽  
General Contractor ◽  
Construction Organizations ◽  
Key Points ◽  
Network Schedule ◽  
Technological Documentation ◽  
The Russian Federation ◽  
The Relationship

This article will discuss the advantages of planning using such elements of organizational and technological documentation as a calendar-network schedule for a more efficient process of managing the production of work during the implementation of an investment and construction project. Also, the main schemes of interaction between the general contractor and the subcontractor will be considered on the basis of key points of their interaction, such as the construction contract and especially the schedule for the construction and installation work. The article will outline the established and most common way of interaction in the Russian Federation, show its advantages and disadvantages, as well as a more progressive approach aimed at improving the relationship between commercial entities, construction organizations and customers.

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