Reflection of neutrons from a resonant potential structure oscillating in space

2021 ◽  
Vol 420 ◽  
pp. 127748
Author(s):  
M.A. Zakharov ◽  
A.I. Frank ◽  
G.V. Kulin
Keyword(s):  
Potential Structure

scholarly journals Bulk and Confined Benzene-Cyclohexane Mixtures Studied by an Integrated Total Neutron Scattering and NMR Method

2021 ◽  
Author(s):  
Terri-Louise Hughes ◽  
Marta Falkowska ◽  
Markus Leutzsch ◽  
Andrew J. Sederman ◽  
Mick D. Mantle ◽  
...  
Keyword(s):  
Neutron Scattering ◽  
Structure Refinement ◽  
Computational Simulation ◽  
Liquid Mixtures ◽  
Coordination Shell ◽  
Bulk Liquid ◽  
Total Neutron ◽  
Time Resolved ◽  
Sample Composition ◽  
Potential Structure

AbstractHerein mixtures of cyclohexane and benzene have been investigated in both the bulk liquid phase and when confined in MCM-41 mesopores. The bulk mixtures have been studied using total neutron scattering (TNS), and the confined mixtures have been studied by a new flow-utilising, integrated TNS and NMR system (Flow NeuNMR), all systems have been analysed using empirical potential structure refinement (EPSR). The Flow NeuNMR setup provided precise time-resolved chemical sample composition through NMR, overcoming the difficulties of ensuring compositional consistency for computational simulation of data ordinarily found in TNS experiments of changing chemical composition—such as chemical reactions. Unique to the liquid mixtures, perpendicularly oriented benzene molecules have been found at short distances from the cyclohexane rings in the regions perpendicular to the carbon–carbon bonds. Upon confinement of the hydrocarbon mixtures, a stronger parallel orientational preference of unlike molecular dimers, at short distances, has been found. At longer first coordination shell distances, the like benzene molecular spatial organisation within the mixture has also found to be altered upon confinement.

Potential structure around the Cassini spacecraft near the orbit of Enceladus

2010 ◽  
Vol 17 (10) ◽  
pp. 102904 ◽  
Author(s):  
J. Olson ◽  
W. J. Miloch ◽  
S. Ratynskaia ◽  
V. Yaroshenko
Keyword(s):  
Potential Structure ◽  
Cassini Spacecraft

scholarly journals Preserving Ordinal Consensus: Towards Feature Selection for Unlabeled Data

2020 ◽  
Vol 34 (01) ◽  
pp. 75-82
Author(s):  
Jun Guo ◽  
Heng Chang ◽  
Wenwu Zhu
Keyword(s):  
Feature Selection ◽  
Unlabeled Data ◽  
Complex Samples ◽  
Noisy Information ◽  
Alternating Minimization Algorithm ◽  
Relative Proximity ◽  
Potential Structure ◽  
Benchmark Datasets ◽  
New Type ◽  
Induced Graph

To better pre-process unlabeled data, most existing feature selection methods remove redundant and noisy information by exploring some intrinsic structures embedded in samples. However, these unsupervised studies focus too much on the relations among samples, totally neglecting the feature-level geometric information. This paper proposes an unsupervised triplet-induced graph to explore a new type of potential structure at feature level, and incorporates it into simultaneous feature selection and clustering. In the feature selection part, we design an ordinal consensus preserving term based on a triplet-induced graph. This term enforces the projection vectors to preserve the relative proximity of original features, which contributes to selecting more relevant features. In the clustering part, Self-Paced Learning (SPL) is introduced to gradually learn from ‘easy’ to ‘complex’ samples. SPL alleviates the dilemma of falling into the bad local minima incurred by noise and outliers. Specifically, we propose a compelling regularizer for SPL to obtain a robust loss. Finally, an alternating minimization algorithm is developed to efficiently optimize the proposed model. Extensive experiments on different benchmark datasets consistently demonstrate the superiority of our proposed method.

scholarly journals Structure of Aqueous RbCl and CsCl Solutions Using X-Ray Scattering and Empirical Potential Structure Refinement Modelling

2018 ◽  
Vol 34 (5) ◽  
pp. 483-491 ◽  
Author(s):  
Yongquan ZHOU ◽  
◽  
Yoshie SOGA ◽  
Toshio YAMAGUCHI ◽  
Yan FANG ◽  
...  
Keyword(s):  
Structure Refinement ◽  
X Ray ◽  
Empirical Potential ◽  
X Ray Scattering ◽  
Potential Structure ◽  
Ray Scattering

Magnetic Field Aligned Potentials as an Acceleration Mechanism at Jupiter

2021 ◽  
Author(s):  
Dave Constable ◽  
Licia Ray ◽  
Sarah Badman ◽  
Chris Arridge ◽  
Chris Lorch ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Temporal Evolution ◽  
Charged Particles ◽  
Uniform Mesh ◽  
Time Varying ◽  
Potential Structure ◽  
Field Aligned Current ◽  
Field Lines ◽  
The Magnetic Field ◽  
Insight Into

<p>Since arriving at Jupiter, Juno has observed instances of field-aligned proton and electron beams, in both the upward and downward current regions. These field-aligned beams are identified by inverted-V structures in plasma data, which indicate the presence of potential structures aligned with the magnetic field. The direction, magnitude and location of these potential structures is important, as it affects the characteristics of any resultant field-aligned current. At high latitudes, Juno has observed potentials of 100’s of kV occurring in both directions. Charged particles that are accelerated into Jupiter’s atmosphere and precipitate can excite aurora; likewise, particles accelerated away from the planet can contribute to the population of the magnetosphere.</p> <p>Using a time-varying 1-D spatial, 2-D velocity space Vlasov code, we examine magnetic field lines which extend from Jupiter into the middle magnetosphere. By applying and varying a potential difference at the ionosphere, we can gain insight into the effect these have on the plasma population, the potential structure, and plasma densities along the field line. Utilising a non-uniform mesh, additional resolution is applied in regions where particle acceleration occurs, allowing the spatial and temporal evolution of the plasma to be examined. Here, we present new results from our model, constrained, and compared with recent Juno observations, and examining both the upward and downward current regions.</p>

Exploring potential structure-activity relationships of graphene-based materials.

2021 ◽  
Vol 350 ◽  
pp. S93-S94
Author(s):  
S. Achawi ◽  
B. Feneon ◽  
J. Pourchez ◽  
V. Forest
Keyword(s):  
Structure Activity Relationships ◽  
Structure Activity ◽  
Potential Structure

Peculiarities of formation of potential of telecommunications enterprises

2021 ◽  
pp. 146-156
Author(s):  
Oleg Fedorenko
Keyword(s):  
Big Data ◽  
Capacity Building ◽  
Financial Analysis ◽  
State Level ◽  
Business Analytics ◽  
Digital Products ◽  
Potential Structure ◽  
Telecommunication Enterprise ◽  
Definition Of ◽  
Cloud Technologies

The purpose of the article – to analyze the peculiarities of forming the potential of a telecommunication enterprise and to suggest ways to increase the efficiency of its use. Research methodology. In the process of preparation of the article the methods of analytical, statistical and financial analysis were used. A scientific novelty is the proposal to use effective indicators of economic efficiency of the enterprise, such as profitability, profitability, cost, return on resources, investment, etc. to assess the effectiveness of the formation and use of the potential of the telecommunications enterprise. Conclusions. 1. The study of trends in the formation of the potential of telecommunications enterprises in Ukraine has determined that the pace of its development corresponds to the basic principles and principles of the concept of economic development and strategy of information society development adopted in Ukraine. The development of the economy of telecommunications enterprises is facilitated at the state level by developing new legislation in the information and telecommunications technologies sector in Ukraine, discussing and adopting new strategies for digital transformation aimed at using big data, blockchain, cloud technologies, robotics and the Internet of Things. 2. It is determined that the potential of a telecommunications enterprise is a unity of organizational, technical and information capabilities that contribute to the preparation and adoption of management decisions and influence its development. Features of capacity building determine the following components that ensure its functioning: software and hardware; personnel; information (databases); organizational, marketing, technical, technological, etc. 3. The system of financial indicators for definition of efficiency of functioning of the formed potential of the telecommunication enterprise is offered. 4. To ensure the formation of a strong potential of the telecommunications company in the work identified a number of key measures, including the creation of information systems, ensuring its operation by special staff, information security, creating new digital products and services, e-commerce and digital marketing. business analytics and big data management, etc. Key words: telecommunication enterprises, capacity building, potential structure of telecommunication enterprise, evaluation indicators, state support.

scholarly journals The occurrence frequency of auroral potential structures and electric fields as a function of altitude using Polar/EFI data

2004 ◽  
Vol 22 (4) ◽  
pp. 1233-1250 ◽  
Author(s):  
P. Janhunen ◽  
A. Olsson ◽  
H. Laakso
Keyword(s):  
Electric Field ◽  
High Altitude ◽  
Electric Fields ◽  
Radial Distance ◽  
Plasma Potential ◽  
Potential Structure ◽  
New Finding ◽  
Low Altitude ◽  
Field Lines ◽  
Auroral Arcs

Abstract. The aim of the paper is to study how auroral potential structures close at high altitude. We analyse all electric field data collected by Polar on auroral field lines in 1996–2001 by integrating the electric field along the spacecraft orbit to obtain the plasma potential, from which we identify potential minima by an automatic method. From these we estimate the associated effective mapped-down electric field Ei, defined as the depth of the potential minimum divided by its half-width in the ionosphere. Notice that although we use the ionosphere as a reference altitude, the field Ei does not actually exist in the ionosphere but is just a convenient computational quantity. We obtain the statistical distribution of Ei as a function of altitude, magnetic local time (MLT), Kp index and the footpoint solar illumination condition. Surprisingly, we find two classes of electric field structures. The first class consists of the low-altitude potential structures that are presumably associated with inverted-V regions and discrete auroral arcs and their set of associated phenomena. We show that the first class exists only below ~3RE radial distance, and it occurs in all nightside MLT sectors (RE=Earth radius). The second class exists only above radial distance R=4RE and almost only in the midnight MLT sector, with a preference for high Kp values. Interestingly, in the middle altitudes (R=3–4RE) the number of potential minima is small, suggesting that the low and high altitude classes are not simple field-aligned extensions of each other. This is also underlined by the fact that statistically the high altitude structures seem to be substorm-related, while the low altitude structures seem to correspond to stable auroral arcs. The new finding of the existence of the two classes is important for theories of auroral acceleration, since it supports a closed potential structure model for stable arcs, while during substorms, different superposed processes take place that are associated with the disconnected high-altitude electric field structures. Key words. Magnetospheric physics (electric fields; auroral phenomena) – Space plasma physics (electrostatic structures)

Sign in / Sign up

Export Citation Format

Share Document