Elementary Blocks Research Articles

A tale of two closely related 1/1 Tsai-type quasicrystal approximants in the RE–Au–M (RE = rare-earth elements, M = p-block elements) systems

A tale of two closely related 1/1 Tsai-type quasicrystal approximants in the RE–Au–<i>M</i> (RE = rare-earth elements, <i>M</i> = <i>p</i>-block elements) systems

Electronic structure and effective mass analysis of doped TiO[formula omitted] (anatase) systems using DFT+[formula omitted

In this work, electronic structure of several doped TiO2 anatase systems is computed using DFT+U. Effective masses of charge carriers are also computed to quantify how the dopant atoms perturb the bands of the host anatase material. U is computed systematically for all the dopants using the linear response method rather than using fitting procedures to physically known quantities. A combination of d and f block elements (Nb, Ta, V, Mo, W, Cr, La, Cu, Co and Ce) are considered as dopants. Depending upon the energies of their outer d or f electrons, the dopants are found to form defect states at various positions in the band structure of host anatase system. Some dopants like Cr, Mo etc. form mid-gap states, which could reduce transparency. Other dopants like Nb, Ta and W are found to have the Fermi levels positioned near the conduction band edge, indicating these systems to exhibit n-type conductivity. From the effective mass analysis, dopants are found to increase the effective mass of charge carriers and the non-parabolic nature of bands. Based on electronic structure and effective mass analysis, Nb, Ta and W are identified to exhibit higher transparency and conductivity as compared to the other dopants considered here. The theoretical results presented here, increase our understanding and show the potential of dopants to alter the properties in anatase TiO2.

Morphotectonics, Seismicity, and Exogenous Processes of the Kola Peninsula

Abstract—The purpose of this study is to determine a morphologically pronounced fault–block structure identified with the neotectonic stage and compare it with sites with manifested exogenous processes, as well as modern and historical paleoseismicity in order to establish faults activated in the postglacial time. Based on the analysis of space images (Landsat-ETM+) and a digital elevation model (GTOPO-30), the territory of the Kola Peninsula and the adjacent part of North Karelia is subjected to morphostructural interpretation with identifying morpholineaments and an elementary block structure. It is shown by the analyzing the directions and extent of elementary, single (simple), and complex (echeloned, parallel conjugated, and imbricated) linear structures and their zones that both linear (fault) and areal (block) structures are characterized by a predominance of a single system of northwestern and northeastern differences with a clear dominance of the former and unimodal distribution of the extent of faults and the area of blocks, depending on their number. This indicates a single (recent) stage in the formation of the morphotectonic appearance of the territory and no discrete hierarchy of the morphostructures. The degree of fragmentation of the territory at different depths is calculated depending on the number and extent of morpholineaments. It is determined that morpholineaments have a high degree of inheritance from Archean–Proterozoic structures (≈50%). Elementary morphotectonic blocks are grouped into composite blocks bounded by linear zones of great extent (100–600 km) having individual physiognomic features determined by fault patterns, which indicates the nature of the neotectonic dynamics and the degree of inheritance or reformation of the structural plan. The localization of manifestations of exogenous processes, epicenters of paleo-, historical, and modern earthquakes is determined on the basis of the analysis of topographic maps scaled at 1:100,000, catalogs of historical and paleoearthquakes, and the consolidated literature (including the data obtained by the authors of this study) on paleoseismic deformations. A geoinformation base is compiled, which is used to simulate the spatial distribution of endo- and exogenous signs of tectonic activity and compare it with the neotectonic fault–block structure. The spatial similarity of endogenous and exogenous activation zones and their confinement to faults, defined as activated in the postglacial time, are revealed. It is revealed that the following elements are most active in the postglacial–Holocene. First, flank elements on the Kola Peninsula along the Barents Sea coast, the Kandalaksha Bay shores, and the Gorlo Strait of the White Sea. Second, the central (nodal) part with the Khibiny and Lovozero massifs. Third, submeridional (transverse) secant structures separating the eastern part of the peninsula from the western part (Khibiny–Kola and Khibiny–Niva). The spatial parameters of the activated zones indicate a range of earthquake magnitudes M ≈ 6.5–7.5 generated by these structures both in the postglacial period and in the Neopleistocene as a whole.

Nanoscale energy deposition frequencies evaluation using GATE simulation tools

Over the last decade, cancer treatment with radiation therapy has evolved significantly due to the improvements in Treatment Planning Systems (TPS). Ideally, these algorithms can determine the dose distribution at the macroscopic scale. However, due to the lack of knowledge, these approaches remain impractical to model radiation side effects at the nanometric scale. This study presents the validation of Monte Carlo (MC) algorithms as a novel approach to model the nanodosimetric effects of radiation therapy particles on real DNA molecule models. A simulation of two simple volumes irradiated by a proton beam is performed to demonstrate the ability of the mixed Geant4-DNA physics model to describe extremely low-energy particle interactions compared to the simple standard Electromagnetic options three physic list. Furthermore, the nanodosimetric effects on the DNA molecule are simulated based on the calculations of the energy frequency deposited by both electron and proton beams in cylinders of three distinct nanometric diameters sizes corresponding to the block elements of the nucleus cell (10 bp, nucleosome, and chromatin fiber). Finally, following the results of this study, the energy deposition frequency in nanoscale cylinders simulated based on the Gate MC code is in good agreement with the results of the series of MOCA codes previously published in the literature.

Fatigue crack growth modelling for S355 structural steel considering plasticity-induced crack-closure by means of UniGrow model

The UniGrow model is an analytical procedure to assess the fatigue crack growth based on elastic–plastic crack tip stresses and strains. The assumption is that fatigue crack growth (FCG) can be considered as a process of successive crack re-initiations resulting from material damage in the crack tip zone. The main parameters of this model are the crack tip radius and the elementary block size. Experimental FCG data obtained for S355 carbon steel showed that assuming the elementary block size with the same value of the crack tip radius to collapse FCG data using UniGrow model is non-coherent with experimental evidence. In this sense, a new approach is proposed by establish a clear distinction between crack tip radius and elementary block size. The value of the crack tip radius, ρ, was defined by correlation with experimental and numerical values of residual compressive stress field ahead of the crack tip while for the elementary block size, ρ∗, a new expression was proposed which relies on effective stress intensity factor range and cyclic yield strength. This research intends to be a valuable contribution for the implementation of UniGrow model to assess the fatigue crack growth of a material.

Structural Design Tuak River Pedestrian Suspension Bridge Anchor Block Type Rigid Symmetric with LISA

Anchor blocks are one of the components and elements that are very risky for suspension bridge construction, because almost The ability The Suspension bridge resistance rests on the cables held in place by the anchor block. This anchor block behavior study is to find out the major stress information occurring in the anchor block elements. In this research, the researcher refers to the Circular Letter of Design Criteria for Rigid Symmetrical Pedestrian Suspension Bridge, and conducts structural modeling using the finite element method-LISA program on anchor blocks. Condition of the anchor block after receiving the appropriate tensile force from the round table at a span of 96 meters, the tensile force of the suspension bridge cable is 664.6 kN, resulting in a stress of 6.184 N/mm2 on the concrete surface of the anchor block using the concrete grade is fc 30 MPa, in the suspension cable of the bridge there is a tension of 22.26 N/mm2 at the point of work. The results of the analysis of the anchor block used on the Tuak River Suspension Bridge with a span of 96 m can meet the required criteria, namely the axial load-bearing capacity, which is greater than the maximum axial force that occurs in the Borpile configuration. In the analysis of the finite element method using the LISA FEA device, a significant stress occurs in the anchor block section with the suspension bridge cable as shown in Figure 9, this occurs because of the large tensile force on the suspension bridge cable and the ability of the anchor block to remain in a stable condition is known.

Scaling laws in fragmentation kinetics

We analyze scaling laws in fragmentation kinetics for mass and velocities of debris and report a new scaling quantity which we call “shattering degree”. To check the universality of the scaling laws, we investigate collisions of clusters comprised of atoms or elementary blocks with very different interaction potentials. Namely, we study Lennard-Jones (L-J), Tersoff and modified L-J potentials and the force associated with Johnson–Kendall–Roberts (JKR) model. They include short, middle and long-ranged inter-particle interactions and also include descriptions for both inter-atomic and macroscopic adhesive bodies interactions. We perform comprehensive molecular dynamics simulations and observe scaling laws for all four potentials for the debris size and velocity distribution. Additionally, we reveal a universal scaling for the shattering degree, which quantifies the fraction of monomers (atoms or elementary blocks) in debris; it holds true for all potentials. We classify the collisions by the outcome and develop a statistical theory, which provides a qualitative explanation for the observed scaling behavior.

Toward Understanding the Correlation between the Charge States and the Core Structures in Thiolate-Protected Gold Nanoclusters.

The charge states of thiolate-protected gold nanoclusters (AuNCs) are vital to their stabilities through affecting the number of the valence electrons. However, the origin of the charge states of AuNCs has not been fully understood yet. Herein, through fulfilling the duet-rule derived Au3(2e) and Au4(2e) elementary blocks in the grand unified model (GUM), analysis on the substantial crystal structures indicates the charge states of AuNCs can correlate with their core structural packing, especially the number of Au3(2e) elementary blocks. In addition, aided by the Au3(2e) block's role in tailoring the population of valence electron, three new AuNCs including Au18(SCH3)14, Au30(SCH3)20, and [Au30(SCH3)21]- are predicted through controllably specifying the exact number of Au3(2e) in the core. This work shows that GUM can bridge the gap among the charge states of the cluster, the inner core structure of the cluster, and the detachment of outer ligands via the electron counting rule.

New Cathode Materials in the Fe-PO4 -F Chemical Space for High-Performance Sodium-Ion Storage.

Sodium and iron make up the perfect combination for the growing demand for sustainable energy storage systems, given the natural abundance and sustainability of the two building block elements. However, most sodium–iron electrode chemistries are plagued by intrinsic low energy densities with continuous ongoing efforts to solve this. Herein, the chemical space of a series of (meta)stable, off‐stoichiometric Fe‐PO4‐F phases is analyzed. Some are found to display markedly improved electrochemical activity for sodium storage, as compared to the amorphous or thermodynamically stable phases of equivalent composition. The metastable crystalline Na1.2Fe1.2PO4F0.6 delivers a reversible capacity of more than 140 mAh g−1 with an average discharge potential of 2.9 V (vs Na+/Na0) resulting in a practical specific energy density of 400 Wh kg−1 (estimated at the material level), outperforming many developed Fe‐PO4 analogs thus far, with further multiple possibilities to be explored toward improved energy storage metrics. Overall, this study unlocks the possibilities of off‐stoichiometric Fe‐PO4‐F cathode materials and reveals the importance to explore the oft‐overlooked metastable or transient state materials for energy storage.

Anatomy of Classical Boron-Boron Bonding: Overlap and sp Dissonance.

Classical bonding is predominantly understood using the insipid spn hybridization for σ-bonds as well as π bonds and their delocalized variants. Because hybridization ignores intricate differences in the energy and size of valence atomic orbitals, its naïve application to classically bonded boron atoms leads to numerous surprises in bond strengths, frontier MOs/bands, and even geometry. Here we show that the sp dissonance caused by size mismatch between the valence s and p orbitals of boron plays a crucial role in its bonding, subtly distinct from that of carbon and silicon. Unlike the heavier p block elements, boron prefers to actively engage its compact 2s orbitals in bonding. This leads to the overreach of p-p σ-type overlap that reduces its magnitude in the entire B─B bonding range. Consequently, the π-type overlap remains substantial, making its electronic structure visibly distinct in saturated and unsaturated regimes. The deltahedral frameworks offer a compromise by breaking this symmetry-enforced dichotomy of classical σ- and π-type bonding and following alternate electron counts that suit the electron deficiency of the boron. The pathological anatomy of classical B─B σ-bonding also explains the origins of puzzling metallic character and disorder in their classical boride networks even with ideal electron count, unlike deltahedral borides. The implications of sp dissonance are illustrated in classical boron networks of various hybridizations, explaining the unusual preference for unique sp3 lattice with strained four-membered rings in CrB4, origins of observed σ holes in MgB2 that lead to its superconducting nature, and the absence of Peierls distortion in LiB.

Graphene-based metasurface solar absorber design for the visible and near-infrared region with behavior prediction using Polynomial Regression

The broadband graphene absorber designs for a visible and near-infrared (NIR) regime is developed in the study. The gold resonator is placed over an MgF2 substrate which is followed by a gold base layer. The graphene spacer is sandwiched between the substrate and resonator layer due to its remarkable conductivity to increase the absorption response. The results are presented for the wavelength spanning from 0.2 µm to 1.2 µm. The average absorption for all three designs is compared and the best design is identified. The proposed structures are also validated by varying various parameters such as resonator thickness, substrate thickness, plus shape width, and needle-point width, and in the process, the absorptance response is improved. The result clearly shows the shift in absorptance response by varying the geometrical parameters. The proposed needle-point shaped solar absorber design can be an elementary block for visible and NIR photovoltaic devices whose utilization can be managed in applications related to energy harvesting. A novel part of this research is using polynomial regression models to predict the absorption capacity at a varying wavelength for variations in angle, resonator thickness, substrate thickness, and needle-point width. Experimental results show that polynomial regression models can predict the values absorption capacity with high accuracy (R2 score).

Modified concept of bond blocks and its applications

The essence of the method for kinetic modeling and CFD calculations of polymer synthesis is presented. The method is named as the modified concept of bond blocks, because species conservation equation are written for polymer chain fragments – bond blocks. For the first time it was shown that it is necessary for all elements of the polymer chains to be represented by elementary bond block and one elementary bond block should not include other elementary bond blocks. For the first time an algorithm has been demonstrated for calculating the molar mass distribution of a polymer based on information of the concentrations of elementary bond blocks (for instance, poly(methyl methacrylate)). The modified concept of bond blocks allows performing CFD calculations by working directly with the CFD simulators interface without writing additional program code. The modified concept of bond blocks is of interest to readers, as it simplifies the technical side of CFD calculations of polymer synthesis. The modified concept of bond blocks was used for the first time to calculate the cationic copolymerization of isobutylene with isoprene in tubular turbulent diffuser-confuser reactors with various feed type of monomers and catalyst solution. It was shown that the highest conversion of monomers can be achieved when fractional feed of catalyst and single-point feed of monomers. For the first time, a method has been proposed for accurate calculation of the shrinkage of a composite material using a modified concept of bond blocks, given the content of associates in a thermosetting binder. This method is useful for controlling the dimensional accuracy of composite products and the designing of technological equipment in which these products are molded.

Early determination and evaluation of technogenic risks within the water purification systems of TSs and TPSs

Purpose. To determine and evaluate technogenic risks within the water purification systems of TSs and TPSs during normal operation in terms of electrocoagulation plant. Methodology. It is proposed to apply a fault tree method for the analysis of various operation failures of water purification facilities in the heat power industry. Additional analysis method, applied at stages one and two of technogenic risk determination, is suggested for its use. The method is based upon the construction of matrix combining states of the system elements. Findings. The aggregation of the combination matrix and fault tree method makes it possible to derive a new grapho-analytical procedure to analyse probabilities of technogenic risk initiation in the context of any water purification system operation both at the stage of its design and at the stage of its work. Originality. Non-routine operation of a water purification system may depend upon certain internal reasons as well the external ones. The reasons pose risks to a situation that at the output of the system, water will turn out being insufficiently purified. It has been identified that in terms of the non-routine operation of water purification system, risk probability is worth analysing with the help of the fault tree serving as graphical representation of causal relationships obtained while considering dangerous situations in reverse order to determine probabilities for their initiation. Practical value. The procedure helps obtain quantitative, qualitative, and causal-consequential indicatorsfacilitating control of technogenic risk initiation in water purification systems. Software has been developed to calculate rapidly the probabilities of running of block elements or water purification system elements in an operation mode or in a failure mode, and see clearly the poorest combinations in terms of an electrocoagulation water purification system.

The joy of factorization at large N: five-dimensional indices and AdS black holes

We discuss the large N factorization properties of five-dimensional supersymmetric partition functions for CFT with a holographic dual. We consider partition functions on manifolds of the form mathrm{mathcal{M}}={mathrm{mathcal{M}}}_3times {S}_{upepsilon}^2 , where ϵ is an equivariant parameter for rotation. We show that, when ℳ3 is a squashed three-sphere, the large N partition functions can be obtained by gluing elementary blocks associated with simple physical quantities. The same is true for various observables of the theories on {mathrm{mathcal{M}}}_3={Sigma}_{mathfrak{g}}times {S}^1 , where {Sigma}_{mathfrak{g}} is a Riemann surface of genus \U0001d524, and, with a natural assumption on the form of the saddle point, also for the partition function, corresponding to either the topologically twisted index or a mixed one. This generalizes results in three and four dimensions and correctly reproduces the entropy of known black objects in AdS6×wS4 and AdS7× S4. We also provide the supersymmetric background and explicitly perform localization for the mixed index on {Sigma}_{mathfrak{g}}times {S}^1times {S}_{upepsilon}^2 , filling a gap in the literature.

Design of thin micro-architectured panels with extension–bending coupling effects using topology optimization

We design the micro-architecture of thin elastic panels to control their macroscopic behavior, accounting simultaneously for in-plane stiffness, out-of-plane stiffness and the extension–bending coupling effects. Our topology optimization method combines inverse homogenization, the Hadamard shape derivative and a level set method in the diffuse interface context to systematically capture within the unit cell the optimal micro-architecture. The efficiency of the solution method is illustrated through four numerical examples where the designed shape yields an important extension–bending coupling. The deformation responses under tensile loading are assessed numerically both on the complete periodic panel and on its homogenized twin plate. The results demonstrate that the simultaneous control of the in-plane, out-of-plane and their coupled behavior enables to shift a flat panel into a dome or a saddle shaped structure. Moreover, the obtained unit cells are elementary blocks to create directly 3D printable objects with shape-morphing capabilities.

Impact of Block Data Components on the Performance of Blockchain-Based VANET Implemented on Hyperledger Fabric

Blockchain, a vital technology in today&#x2019;s era, changed the way we share, manage and exchange our data in a centralized way to decentralized architecture. With the increasing demand for Blockchain, various platforms are available to implement public, private, consortium, or permissioned, permissionless Blockchain. Hyperledger, an open-source, permissioned, distributed ledger-based Blockchain, was hosted by Linux. This paper explores Hyperledger Fabric Private Blockchain Network (HFPBN). The architecture of HFPBN with its components and transaction flow is explored in detail. The Blockchain in HFPBN comprises multiple blocks that are linked to each other. The block elements are discussed in detail with their type and size, and after that, the total size of the block depending upon various parameters is calculated. Further, one application of Blockchain, i.e., Vehicular Ad-hoc Networks (VANETs), is discussed in this paper as a case study. The VANET application is being implemented on the Hyperledger Fabric platform. Formulas showing the dependency of various parameters like endorsement policy, number of transactions, and number of reads and writes on block size are derived and shown in their relationship through the graph for the VANET system. The impact of block size on various performance parameters like throughput, latency, memory, and CPU utilization for the VANET system is then analyzed using Hyperledger Caliper. An optimal required value of throughput and latency is achieved for Blockchain-based VANET. Also, the Hyperledger Fabric platform seems suitable for many applications as it creates separate Blockchain for different applications.

Introduction to logical entropy and its relationship to Shannon entropy

We live in the information age. Claude Shannon, as the father of the information age, gave us a theory of communications that quantified an “amount of information,” but, as he pointed out, “no concept of information itself was defined.” Logical entropy provides that definition. Logical entropy is the natural measure of the notion of information based on distinctions, differences, distinguishability, and diversity. It is the (normalized) quantitative measure of the distinctions of a partition on a set-just as the Boole–Laplace logical probability is the normalized quantitative measure of the elements of a subset of a set. And partitions and subsets are mathematically dual concepts – so the logic of partitions is dual in that sense to the usual Boolean logic of subsets, and hence the name “logical entropy.” The logical entropy of a partition has a simple interpretation as the probability that a distinction or dit (elements in different blocks) is obtained in two independent draws from the underlying set. The Shannon entropy is shown to also be based on this notion of information-as-distinctions; it is the average minimum number of binary partitions (bits) that need to be joined to make all the same distinctions of the given partition. Hence all the concepts of simple, joint, conditional, and mutual logical entropy can be transformed into the corresponding concepts of Shannon entropy by a uniform non-linear dit-bit transform. And finally logical entropy linearizes naturally to the corresponding quantum concept. The quantum logical entropy of an observable applied to a state is the probability that two different eigenvalues are obtained in two independent projective measurements of that observable on that state.

Paramagnetic resonance investigation of mono- and di-manganese-containing systems in biochemistry.

Although not as important as iron, manganese is one of the key transition metal (d block) elements in biochemistry. The role of Mn in photosynthesis is perhaps its "starring role," but has been extensively covered elsewhere and will not be discussed in this chapter. In contrast to iron, for which 57Fe Mӧssbauer effect (nuclear gamma resonance) spectroscopy is available, 55Mn (100% abundant) lacks this ability. Instead, the defining technique for Mn is electron paramagnetic resonance (EPR) spectroscopy, as Mn(II), Mn(IV), and even Mn(III), as well as certain di-Mn systems are generally EPR active. This chapter describes how EPR and its advanced derivatives, electron spin echo envelope modulation (ESEEM) and electron-nuclear/electron-electron double resonance (ENDOR/ELDOR) spectroscopies, provide valuable biochemical information on many Mn-containing systems. These include endogenous Mn in mono- and di-Mn (protein) enzymes as well as brief mention of applications to Mn in non-protein biological systems.

Construction of a discrete topological self-assembly space for packed block elements simulating nanoparticles

Construction of a discrete topological self-assembly space for packed block elements simulating nanoparticles

О КОНТАКТНЫХ ЗАДАЧАХ С ДЕФОРМИРУЕМЫМ ШТАМПОМ

This paper presents one of the methods for studying the behavior of deformable stamps on a deformable base. It is based on a new universal modeling method previously published by the authors, used in boundary value problems for systems of partial differential equations. Its advantage is the possibility of avoiding the need to solve complex boundary value problems for systems of differential equations by replacing them with separate differential equations, among which the Helmholtz equations are the simplest. With the help of combinations of solutions of boundary value problems for this equation, it is possible to describe the behavior of complex solutions of multicomponent boundary value problems, including for cracks of a new type formed by objects on a deformable base, and models of nano particles located on deformable multicomponent bases. However, without the ability to solve contact problems for deformable stamps, these models are not built. The mixed problem is reduced to the solution of the Wiener–Hopf integral equation. Two cases are considered: the case of a large-width strip stamp and the case of a semi-infinite stamp. A packed block element is accepted as a deformable stamp, as a solution of the Helmholtz equation in the specified area. Mechanically, it can be imitated as a membrane that is located on a multilayer medium occupying the contact area. A combination of such objects can be used to describe solutions to the contact problem for flat deformable objects of more complex rheology, as well as for three-dimensional ones. Along with the proof of constructing an exact solution to the contact problem under consideration, the appearance of unknown functionals is noted in the course of the study. In problems with an absolutely solid stamp, they do not occur. The paper finds a way to determine them and an analytical representation of them is obtained. It is suggested that their appearance will be typical for solving other contact problems with deformable stamps. The features of the method and the results obtained are discussed.