bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of the National Health Insurance Scheme on Healthcare Utilization and Out-of-Pocket Payment: Evidence from GLSS 7
Authors: Sarkodie Adu Owusu
Published: November 2021

The Ghana National Health Insurance Scheme (NHIS) was established in 2003, Act, 2003 (Act 650), but was later replaced with the National Health Insurance Act, 2012 (Act 852) to get rid of the then “cash and carry” system of paying for healthcare. The aim of the scheme was to reduce the cost of healthcare provision and increase access to healthcare. This paper investigates the effect of the National Health Insurance Scheme (NHIS) on healthcare utilization and out-of-pocket payment, from the providers’ perspective. The study uses data from the seventh round of the Ghana Living Standards Survey (GLSS 7) conducted in 2016/2017 and employs the estimation method of Propensity Score Matching (PSM). The findings are that enrollment onto Ghana’s National Health Insurance Scheme (NHIS) increases healthcare utilization by 26% and decreases out-of-pocket payment by 4%. However, about 48% of the population are still not enrolled, citing various reasons. Even those who enrolled, about 30% had dropped out for several reasons. The study identifies age, income, education, sex, and location of residence as the main determinants of enrolling onto the NHIS. I show that the National Health Insurance Scheme increases healthcare utilization and reduces out-of-pocket payment in Ghana. A number of Ghanaians have either not registered or registered but have stopped enrolling citing no money, no need for NHIS, and no confidence in the system’ as reasons. Any policy to invigorate the public confidence in NHIS and increases enrollment should be targeted at the young, poor, less educated, males, and rural dwellers.
Rational design of PVDF/BaTiO3 nanoparticle/Cu nanowire ternary nanocomposite films for optimal piezoelectric power generation
Authors: Park Donghyuck , Kim Kwanlae
Published: November 2021

Flexible polymers, ferroelectric ceramic nanoparticles, and conductive nanomaterials have been intensively studied with the aim of exploiting their unique properties synergistically and producing a ternary composite displaying excellent piezoelectric performance. Therefore, it is important to understand the role of conductive nanomaterials in ternary nanocomposites for piezoelectric power generation. In this study, the effect of Cu nanowire (CuNW) addition on the dielectric, ferroelectric, and piezoelectric properties of poly(vinylidene fluoride) (PVDF)/BaTiO3 nanoparticle (BTNP)/CuNW composite films was systematically investigated. The experimental results reveal that ternary composites with 0.04 vol. % CuNWs generated the highest total charge and power density among samples of varying CuNW content. When 0.04 vol. % CuNWs were incorporated into the PVDF/BTNP binary composite, the remanent polarization (Pr) increased from 0.51 to 1.63μC/cm2 due to an enhanced effective electric field. However, when the CuNW content exceeded 0.04 vol. %, Pr started to decrease owing to an increase in the leakage current and the enhancement in the pinning effect of the PVDF dipoles. When an excessive amount of CuNWs was added to the composite, the piezoelectric performance showed only a moderate decrease owing to the enhanced stress transfer. Conductive nanowires are often incorporated into piezoelectric ternary composites to facilitate the dispersion of piezoelectric nanoparticles and for stress transfer. However, composites with a more than 0.04 vol. % CuNWs have a lower net polarization and piezoelectric power density. When the CuNW content is optimized (0.04 vol. %), the maximum power density of the ternary composite film can be enhanced by up to 520%.
The essential synchronization backbone problem
Authors: Diggans C. Tyler , Fish Jeremie , AlMomani Abd AlRahman R. , Bollt Erik M.
Published: November 2021

Network optimization strategies for the process of synchronization have generally focused on the re-wiring or re-weighting of links in order to (1) expand the range of coupling strengths that achieve synchronization, (2) expand the basin of attraction for the synchronization manifold, or (3) lower the average time to synchronization. A new optimization goal is proposed in seeking the minimum subset of the edge set of the original network that enables the same essential ability to synchronize in that the synchronization manifolds have conjugate stability. We call this type of minimal spanning subgraph an essential synchronization backbone of the original system, and we present two algorithms: one is a strategy for an exhaustive search for a true solution, while the other is a method of approximation for this combinatorial problem. The solution spaces that result from different choices of dynamical systems and coupling schemes vary with the level of a hierarchical structure present and also the number of interwoven central cycles. Applications can include the important problem in civil engineering of power grid hardening, where new link creation may be costly, and the defense of certain key links to the functional process may be prioritized.
Explore the correlation between intervalley scattering and phonon bottleneck effect on the hot carrier relaxation in bulk GaSb and InN for hot carrier solar cells
Authors: Zhang Yi , Jia Xuguang , Liu Shuang , Wu Kefan , Zhang Jiayu , Conibeer Gavin
Published: November 2021

Slowed carrier intervalley scattering (IVS) may trap some photo-excited carriers within side valleys and reduce the overall thermalization rate. On the other hand, the thermalization rate could also be significantly retarded within the gamma valley by slowing the Klemens decay due to a large phononic bandgap via the phonon bottleneck effect (PBE). However, the correlation between IVS and PBE on slowing the carrier relaxation rate is still unclear. Herein, high-quality bulk InN and GaSb with similar electronic bandgap but remarkably different phononic structures are studied to clarify the above correlation through picosecond time-resolved photoluminescence. The occurrence of IVS is controlled by using different pump energies at high carrier density (∼1019 cm−3). The relaxations of carriers excited at the band edge just above and far above the side valley threshold are, therefore, studied in GaSb. It shows that the effective hot carrier lifetime (τ1) of GaSb gets significantly extended with higher pump energy mainly due to more carriers being trapped in side valleys through IVS. Nevertheless, the longest τ1 of GaSb is still shorter than the shortest τ1 of InN with a more polar nature and larger phononic bandgap. This implies that PBE plays a more decisive role in retarding Γ valley carrier relaxation than the slowed IVS. It indicates that the large phononic bandgap and Fröhlich coupling constant are keys to the slow thermalization rate if the Fröhlich interaction dominates. If the deformation potential interaction dominates this process, then low side valley threshold energy and the Fröhlich constant determine the reduction of the overall thermalization rate.
Magnetic domain structure across the austenite–martensite interface in Ni50Mn25Ga20Fe5 single crystalline thin foil
Authors: Vronka M. , Straka L. , Klementová M. , Heczko O.
Published: November 2021

The magnetic domain structure (MDS) at the martensite transformation interface is relevant for the complete understanding of functionalities in magnetic shape memory alloys. We study the MDS in Ni50Mn25Ga20Fe5 single crystalline foil using Lorentz transmission electron microscopy. The transformation interface is stabilized by decreasing foil thickness at a thickness of about 40 nm. The martensite in the thicker region contains no twin domains and exhibits dense labyrinth MDS with magnetization out-of-plane. The austenite in the thinner region exhibits broad magnetic domains with magnetization in-plane. The transformation interface is about 1 μm broad, formed by an unusual nanosized laminated structure of austenite and martensite. Within the interface region, the two distinct MDSs interpenetrate each other, with a labyrinth MDS of martensite changing suddenly to broad magnetic domains of austenite. The changes from dense to broad domains do not follow the underlying phase changes exactly but occur on antiphase boundaries, revealing their role in the overall MDS formation.
Effect of nanoparticle surfactants on droplet formation in a flow-focusing microchannel
Authors: Qi Jie , Yu Zheng Liang , Liao Guo Peng , Luo Zheng Yuan , Bai Bo Feng
Published: November 2021

Nanoparticle surfactants, formed at liquid–liquid interfaces by the interactions between functional groups on nanoparticles and polymers having complementary end-functionality, have been recently proposed as an excellent interface stabilizer to cover liquid droplets for applications of substance encapsulation and delivery. However, the effects of nanoparticle surfactants on the production of liquid droplets in a microfluidic channel have not been comprehensively understood yet, which is a key prerequisite for achieving various functions in real applications. In this study, we have performed a systematic investigation on the effects of nanoparticle surfactants on droplet formation in a flow-focusing microchannel by using microfluidic experiments and theoretical analysis. We have found that simultaneously adding carboxylated nanoparticles into the dispersed phase and amino-terminated polymers into the continuous phases significantly decreases the droplet size but increases the production rate. More importantly, we have indicated that the combined effect of nanoparticles and polymers is much greater than the sum of their individual effects, which is mainly attributed to the significant reduction of the oil–water interfacial tension by the formation of nanoparticle surfactants. Besides, via analyzing the competition between hydrodynamic and interfacial forces acting on the droplet, we have established a theoretical criterion for the prediction of the droplet size with considering the effects of nanoparticle surfactants, which shows a good agreement with the experimental data.
Gate-controlled supercurrent in ballistic InSb nanoflag Josephson junctions
Authors: Salimian Sedighe , Carrega Matteo , Verma Isha , Zannier Valentina , Nowak Michał P. , Beltram Fabio , Sorba Lucia , Heun Stefan
Published: November 2021

High-quality III–V narrow bandgap semiconductor materials with strong spin–orbit coupling and large Landé g-factor provide a promising platform for next-generation applications in the field of high-speed electronics, spintronics, and quantum computing. Indium antimonide (InSb) offers a narrow bandgap, high carrier mobility, and small effective mass and, thus, is very appealing in this context. In fact, this material has attracted tremendous attention in recent years for the implementation of topological superconducting states supporting Majorana zero modes. However, high-quality heteroepitaxial two-dimensional (2D) InSb layers are very difficult to realize owing to the large lattice mismatch with all commonly available semiconductor substrates. An alternative pathway is the growth of free-standing single-crystalline 2D InSb nanostructures, the so-called nanoflags. Here, we demonstrate fabrication of ballistic Josephson-junction devices based on InSb nanoflags with Ti/Nb contacts that show a gate-tunable proximity-induced supercurrent up to 50 nA at 250 mK and a sizable excess current. The devices show clear signatures of subharmonic gap structures, indicating phase-coherent transport in the junction and a high transparency of the interfaces. This places InSb nanoflags in the spotlight as a versatile and convenient 2D platform for advanced quantum technologies.
Polarized neutron reflectometry characterization of perpendicular magnetized Ho3Fe5O12 films with efficient spin-orbit torque induced switching
Authors: Bai H. , Zhu Z. Z. , Zhan X. Z. , Yang M. , Li G. , Ke J. T. , Hu C. Q. , Zhu T. , Cai J. W.
Published: November 2021

Rare-earth iron garnet films with perpendicular magnetic anisotropy (PMA) are important to develop magnon-based spintronic devices. In this study, high quality epitaxial Ho3Fe5O12 (HoIG) films with PMA are fabricated on (111) Y3(Sc2Ga3)O12 substrates by sputtering. The magnetization compensation temperature of HoIG films is determined to be 130 K, highly consistent with its bulk value. The magnetic dead layer at the interface is quantified as thin as about 0.6 nm through polarized neutron reflectivity. Furthermore, spin–orbit torque switching in HoIG/Pt films is realized with the threshold current density of 1.4 × 1011 A/m2 and assisting field as small as 10 Oe. These results provide one more alternative for spintronic materials using compensated ferrimagnetic insulators.
Ultrafast sorting: Excimeric π–π stacking distinguishes pyrene-N-methylacetamide isomers on the ultrafast time scale
Authors: Basuroy Krishnayan , de J. Velazquez-Garcia Jose , Storozhuk Darina , Gosztola David J. , Veedu Sreevidya Thekku , Techert Simone
Published: November 2021

Pyrene based molecules are inclined to form excimers through self-association upon photoexcitation. In this work, the pyrene core is functionalized with the N-methylacetamide group at the position 1 or 2 to develop pyren-1-methylacetamide (PyMA1) and pyren-2-methylacetamide (PyMA2), respectively. Upon photoexcitation with 345 nm, a portion of molecules in PyMA1 and PyMA2 solutions at ≥1.0 mM have formed static excimers. The steady state spectroscopic measurements suggest that, whether it is the dimerization of molecules in the ground state (GS) or in excimer formation, characteristic signs are more pronounced in PyMA1 than its isomeric counterpart, PyMA2. The shift of the excimer band in their respective emission spectra suggests that the extent of overlap in π–π stacking is greater for PyMA1 than for PyMA2 in the excited state. The optimized geometry of dimers in toluene shows that the overlapping area between the pyrene moieties in π–π stacking between the dimers is greater for PyMA1 than for PyMA2 in GS. The natural bond orbital analysis with the optimized GS geometries shows that the stabilization/interaction energy between the dimers in π–π stacking is higher in PyMA1 compared to PyMA2 in toluene. The transient absorption (TA) measurements in toluene over the fs–ps regime (fs-TA) showed that the formation of static excimers with pre-associated dimers in PyMA1 happens in ∼700 fs whereas the excimers for the pre-associated dimers in PyMA2 have formed in slightly slower time scale (∼1.95 ps). Contrary to what was observed in solution, the extent of overlap in π–π stacking is lower for PyMA1 dimers (∼17%) than for PyMA2 dimers (∼37%) in single crystals.
Effect of continuous light on antioxidant activity, lipid peroxidation, proline and chlorophyll content in
Authors: Kumar Deepak , Singh Hanwant , Bhatt Upma , Soni Vineet
Published: November 2021

Longer photoperiod in form of continuous light (24-h photoperiod without dark interruption) can alter the various physiological and biochemical processes of the plant. This study aimed to evaluate the effects of continuous light on various biochemical parameters associated with the growth and development of Vigna radiata L. (mung bean). The findings showed that leaf size and chlorophyll content of seedlings grown under continuous light were significantly greater than control plants subjected to 12 h light/12 h dark (12/12 h). The activity of antioxidant enzymes superoxide dismutase (SOD, 30.81%), catalase (CAT, 16.86%), guaiacol peroxidase (GPOD, 12.27%), malondialdehyde, (MDA, 39.31) and proline (14.81%) were notably higher in 24/0 h light period than 12/12 h light period grown seedling at an early stage (on Day 6) while they were constant at the later stage of development. Increased activity of amylase and invertase reveals higher assimilation and consumption of photosynthetic products. This study revealed that plants were stressed at first. However, they gradually became acclimated to continuous light and efficiently used the excess light in carbon assimilation.
Neural networks to learn protein sequence–function relationships from deep mutational scanning data
Authors: Gelman Sam , Fahlberg Sarah A. , Heinzelman Pete , Romero Philip A. , Gitter Anthony
Published: November 2021

Significance

Understanding the relationship between protein sequence and function is necessary to design new and useful proteins with applications in bioenergy, medicine, and agriculture. The mapping from sequence to function is tremendously complex because it involves thousands of molecular interactions that are coupled over multiple lengths and timescales. We show that neural networks can learn the sequence–function mapping from large protein datasets. Neural networks are appealing for this task because they can learn complicated relationships from data, make few assumptions about the nature of the sequence–function relationship, and can learn general rules that apply across the length of the protein sequence. We demonstrate that learned models can be applied to design new proteins with properties that exceed natural sequences.
A role of anterior cingulate cortex in the emergence of worker–parasite relationship
Authors: Ahn Soyoun , Kang Yujeong , Lee Jong Won , Jeong Se Jin , Lee Yoo Jin , Lee Soomin , Kim Jeongyeon , Koo Ja Wook , Kim Jeansok J. , Jung Min Whan
Published: November 2021

Significance

Although exploitation of labor in groups is a hallmark of social animals, its underlying neural mechanisms remain unknown. We explored this matter using a “social problem” paradigm in which one rat, the “worker,” predominantly performed lever-pressing for food delivery while the other “parasitic” rats consumed nearly all delivered food by crowding the feeder in anticipation. We found that the anterior cingulate cortex (ACC) plays a necessary role in the worker’s lever-press behavior under social situations, and that c-Fos immunoreactivity and GABA
A
receptor– and potassium channel–related messenger RNA expressions differed between the worker’s and parasite’s ACC. These results suggest that relative activation levels of the ACC could be a crucial factor determining the workload imbalance under social dilemma settings.
Structure of the translating
Neurospora
ribosome arrested by cycloheximide
Authors: Shen Lunda , Su Zhaoming , Yang Kailu , Wu Cheng , Becker Thomas , Bell-Pedersen Deborah , Zhang Junjie , Sachs Matthew S.
Published: November 2021

Significance

The ribosome has the central role in the translation of RNA. The elongation function of most eukaryotic ribosomes is arrested by the drug cycloheximide (CHX). The site of CHX binding is known. In this work, we determine the structure of a translating ribosome of a filamentous fungus arrested by CHX. By doing so, the specific state of the ribosome arrested in translation is revealed. This work is significant because it provides a structural basis to establish CHX’s mechanism of action. It provides a model for a fungal ribosome and insights into the structure and function of eukaryotic ribosomes through comparative analyses of its features with those from other species.
What is a word in Brokpa?
Authors: Wangdi Pema
Published: November 2021

This paper investigates the structure of phonological word and grammatical word in Brokpa, a Tibeto-Burman (Trans-Himalayan) language of Bhutan. Defining features of a phonological word include stress, tone, and segmental properties. A grammatical word is defined based on conventionalized coherence and meaning, fixed order of morphemes, and its behaviour in relation to derivational and inflectional marking. Grammatical and phonological words in Brokpa coincide in most instances. Typical mismatches include words involving non-cohering compounds and non-cohering reduplication. A formal distinction between phonological and grammatical word is the key to our understanding of the interactions between different parts of grammar in Brokpa, and help resolve potential ambiguities of the term “word” in this language.
Hearsay evidential marking strategy in Lhagang Tibetan
Authors: Suzuki Hiroyuki , Wangmo Sonam
Published: November 2021

This exploratory study focuses on the use of hearsay evidential marking in the course of storytelling in a Tibetic language, Lhagang Tibetan, combining a descriptive linguistic approach with a literary-theoretic analysis. Tibetic languages generally possess a morpho-syntactically encoded evidential-epistemic system, in which the hearsay evidential represents a non-first-hand information source. However, we find a random use of the hearsay evidential marker in the oral literature of Lhagang Tibetan, although it has been transmitted from one generation to another by storytellers. The article aims to provide a reasonable explanation for the use of the hearsay evidential in storytelling. It proposes that hearsay evidential marking reflects the speaker’s attitude towards the utterance to either avoid full responsibility for the utterance or enhance the utterance’s authenticity. The former objective principally appears in telling a story based on a weak memory of the story; the latter appears in telling a legend. This explanation is supported by oral literature theory, especially the arguments regarding the difference between folktales and legends.
Key comparison BIPM.RI(I)-K7 of the air-kerma standards of the NMIJ, Japan and the BIPM in mammography x-rays
Authors: Kessler C , Burns D , Tanaka T , Kurosawa T
Published: November 2021

Main text

A new key comparison has been made between the air-kerma standards of the NMIJ and the BIPM in mammography x ray beams. The results show the standards to be in agreement at the level of the expanded uncertainty of 7.2 parts in 103. The results are analysed and presented in terms of degrees of equivalence for entry in the BIPM key comparison database.

To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database https://www.bipm.org/kcdb/.

The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
Nitrous oxide in nitrogen (1000μmol/mol)
Authors: Wu Hai , Ma Haomiao , Wang Defa , Lim Jeongsik , Lee Jinbok , Moon Dongmin , Akima Dai , Kobayashi Midori , Uehara Shinji , Liu Hsin-Wang , Huang Chiung-Kun , Lin Tsai-Yin , Tshilongo James , Mogale David , Lushozi Silindile , Laongsri Bunthoon , Wongjuk Arnuttachai , Soni Daya , Johri Prabha , Aggarwal Shankar G , Singh Khem , Bhat Sulakshina , Konopelko L A , Kustikov Y A , Kolobova A V , Pankratov V V , Ivakhnenko B V , Efremova O V
Published: November 2021

Main text

To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database https://www.bipm.org/kcdb/.

The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
Noncommutative (A)dS and Minkowski spacetimes from quantum Lorentz subgroups
Authors: Ballesteros Angel , Gutierrez-Sagredo Ivan , Herranz Francisco J
Published: November 2021

The complete classification of classical r-matrices generating quantum deformations of the (3 + 1)-dimensional (A)dS and Poincaré groups such that their Lorentz sector is a quantum subgroup is presented. It is found that there exists three classes of such r-matrices, one of them being a novel two-parametric one. The (A)dS and Minkowskian Poisson homogeneous spaces corresponding to these three deformations are explicitly constructed in both local and ambient coordinates. Their quantization is performed, thus giving rise to the associated noncommutative spacetimes, that in the Minkowski case are naturally expressed in terms of quantum null-plane coordinates, and they are always defined by homogeneous quadratic algebras. Finally, non-relativistic and ultra-relativistic limits giving rise to novel Newtonian and Carrollian noncommutative spacetimes are also presented.
Reconstruction and electronic properties of β-Li3PS4|Li2S interface
Authors: Wei Chengdong , Xue Hongtao , Li Zhou , Zhao Fenning , Tang Fuling
Published: November 2021

The morphology and properties of the interface between solid electrolyte and electrode have important impacts on all-solid-state lithium-sulfur batteries’ performance. We used the first-principles calculations to explore the interface between Li2S cathode and β-Li3PS4 (lithium thiophosphate, LPS) solid electrolyte, including lattice structure, mechanical, electrical properties, interface contact type, and charge distribution in real space. It is found that the interface is significantly reconstructed, and the Li atoms at the interface move mainly parallel to the interface plane. The interface density states introduce metallic properties, mainly contributed by the Li-s and S-s, -p orbitals in Li2S and S-p orbitals in LPS. The highest occupied molecular orbitals of the LPS electrolyte are lower than the electrochemical potential (Fermi level) of the Li2S cathode, thus the electrolyte and cathode materials are reasonable and stable in thermodynamics. Interface density of states shows electrons on the interface do not penetrate from Li2S into LPS, and do not leak electrons to cause electron conduct in LPS. Besides, the interface is an n-type Schottky barrier with a barrier value of 1.0 eV. The work-function of the interface indicates that there is a space charge layer (SCL) by the redistribution of electrons, which is in agreement with the result of interface charge density difference. The electron/hole pairs will be separate, realizing high current charge and discharge capability because of the SCL.
Universality of mesoporous coal gasification slag for reinforcement and deodorization in four common polymers
Authors: Zhang Jiupeng , Zuo Jing , Liu Yang , Zhang Junyu , Fu Wenjing , Zhang Jinyi , Miao Shiding , Wei Cundi
Published: November 2021

Mesoporous adsorbents and polymer deodorants are difficult to implement on a large scale because of their complicated preparation methods. Herein, a mesoporous adsorbent (CGSA) with a specific surface area of 564 m2 g−1 and a pore volume of 0.807 cm3 g−1 was prepared from solid waste coal gasification slag using a simple acid leaching process. The adsorption thermodynamics and adsorption kinetics results verified that the adsorption mechanism of propane on CGSA was mainly physisorption. Then the universality of CGSA in different polymers was investigated by introducing CGSA and its commercialized counterparts (CaCO3, and zeolite) into four common polymers. When the filler content was 30 wt%, the average reinforcement effect of CGSA on the tensile, flexural, and impact strengths of the four polymers was 46.68%, 83.62%, and 211.90% higher than that of CaCO3, respectively. Gas chromatography results also showed that CGSA significantly decreased total volatile organic compound emissions from the composites, and its optimal deodorization performance reached 69.58%, 81.33%, and 91.09% for different polymers, respectively, far exceeding that of zeolite. Therefore, this study showed that low-cost, high-performance, and multifunctional mesoporous polymer fillers with excellent universality can be manufactured from solid contaminants.
Preparation of novel porous Al2O3–SiO2 nanocomposites via solution-freeze-drying-calcination method for the efficient removal of uranium in solution
Authors: Wu Maoling , Ding Ling , Liao Jun , Zhang Yong , Zhu Wenkun
Published: November 2021

In this work, the efficient extraction of uranium in solution using Al2O3–SiO2-T was reported. Kinetics and isotherm models indicated that the removal process of uranium on Al2O3–SiO2-T accorded with pseudo-second-order kinetic model and Langmuir isotherm model, which showed that the adsorption process was a uniform mono-layer chemical behavior. The maximum adsorption capacity of Al2O3–SiO2-T reached 738.7 mg g−1, which was higher than AlNaO6Si2 (349.8 mg g−1) and Al2O3–SiO2-NT (453.1 mg g−1), indicating that the addition of template could effectively improve the adsorption performance of Al2O3–SiO2 to uranium. Even after five cycles of adsorption–desorption, the removal percentage of uranium on Al2O3–SiO2-T remained 96%. Besides, the extraction efficiency of uranium on Al2O3–SiO2-T was 72.5% in simulated seawater, which suggested that the Al2O3–SiO2-T was expected to be used for uranium extraction from seawater. Further, the interaction mechanism between Al2O3–SiO2-T and uranium species was studied. The results showed that the electrostatic interaction and complexation played key roles in the adsorption process of Al2O3–SiO2-T to uranium.
Synthesis of stabilizer-free, homogeneous gold nanoparticles by cold atmospheric-pressure plasma jet and their optical sensing property
Authors: Xuan Le Thi Quynh , Nguyen Linh Nhat , Dao Nguyen Thuan
Published: November 2021

Recently, cold atmospheric-pressure plasma has been studied extensively as an efficient and green method to synthesize gold nanoparticles (AuNPs). Although the characteristics of the AuNPs, especially their homogeneousness, depend very much on the plasma synthesis parameters, there is a lack of a study involving these parameters systematically. Moreover, most of AuNPs-cold-plasma synthesis reports so far either required organic capping agents or resulted in highly non-uniform AuNPs. In this work, we systematically study the effect of most important synthesis parameters— including distance from the plasma jet to the solution, gas flow rate, plasma frequency, volume and concentration of the precursor, plasma interaction time as well as the effect of the synthesis environment (humidity and temperature)—on the uniformity of the AuNPs. Through various characterization measurements, we show that homogeneous and highly stable intrinsic AuNPs with an average size of 45 nm can be obtained with optimized synthesis parameters and in the absence of a stabilizer. The synthesized AuNPs yield advanced optical sensing properties in comparison with commercial AuNPs and can be further applied in developing versatile and high-sensitivity biosensors.
QCD at finite chemical potential in and out-of equilibrium
Authors: Soloveva Olga , Moreau Pierre , Bratkovskaya Elena
Published: November 2021

We review the transport properties of the strongly interacting quark-gluon plasma (QGP) created in heavy-ion collisions at ultrarelativistic energies, i.e. out-of equilibrium, and compare them to the equilibrium properties. The description of the strongly interacting (non-perturbative) QGP in equilibrium is based on the effective propagators and couplings from the Dynamical QuasiParticle Model (DQPM) that is matched to reproduce the equation-of-state of the partonic system above the deconfinement temperature T

c
from lattice QCD. We study the transport coefficients such as the ratio of shear viscosity and bulk viscosity over entropy density, diffusion coefficients, electric conductivity etc versus temperature T and baryon chemical potential μ

B
. Based on a microscopic transport description of heavy-ion collisions we, furthermore, discuss which observables are sensitive to the QGP formation and its properties.
Long-range robust multifilament arrays from terawatt femtosecond beam
Authors: Mitina E , Uryupina D , Zhidovtsev N , Volkov R , Kosareva O , Savel’ev A
Published: November 2021

Multiple filament’s formation on a long atmospheric path was studied for an amplitude modulation of the terawatt femtosecond beam with the four and six hole masks. Filaments appeared at the distance that is determined by the Fresnel lens formed by a hole, not by the self focusing theory for the unrestricted (Gaussian like) beam. This lens focuses 1/3 of the energy passing through the hole to the beam spot ≈1 mm in diameter. The robust multifilament array 10–15 m in length was observed if the energy per hole was ≈1-1.5 mJ (pulse duration 50 fs), while each hole produces bundle of a few filaments at higher energies.
A Study of Possible Reasons of the Damage by Electric Current of Traction Induction Motors Bearings of Electric Trains Lastochka and the Ways to Prevent This
Authors: Pustovetov M
Published: November 2021

There is a problem of damage of bearings of traction induction motors of electric trains Lastochka by electric current. Based on the fact that the bearings have a ceramic insulation coating, and the cases of its electrical breakdown is not fixed, the authors put forward a version that a high-frequency current flows through the bearing as through an electric capacitance. The analysis show that the cause of the current can be a radio standard GSM-R. The proposed technical solution against the damage of bearings: the use of grounding shaft rings, replace the bearings on the other with ceramic rolling elements, arrangement of separate high-frequency grounding for the GSM-R antenna.
On the Approach to Optimization of Restoration Works at Railway Facilities
Authors: Dergachev A I , Dergachev S A , Chernykh A K , Abu-Khasan M S
Published: November 2021

The article considers an approach to solving the problem of finding the optimal option for the work teams to carry out a complex of restoration works at railway facilities destroyed as a result of an emergency. An approach to solving this problem is proposed, based on the methods of graph theory, fuzzy set theory, and mathematical programming. The proposed approach is illustrated by a meaningful example.
Control System of a Robotic Irrigation Machine Based on the Mamdani Fuzzy Algorithm
Authors: Kafiev I , Romanov P , Romanova I
Published: November 2021

The article analyzes the tasks that can be solved by agricultural robots. The purpose of the study was the robotization of the "Fregat" type crop irrigation machine by the fuzzy control of irrigation technological processes, which allows to control the irrigation rate. It is proposed to use in a robotic irrigation machine the analog valve-setter of the speed of the last cart, powered by electricity. It is recommended to include a diagnostic subsystem in the fuzzy control system of the flow control valve, which includes sensors for measuring the soil moisture and the slope of the irrigation machine in various areas of the field. The mathematical model of fuzzy control of the irrigation machine is developed based on the software control of the water supply depending on the terrain of the field, the speed of irrigation machine and soil moisture to reduce water consumption and improve the efficiency and quality of irrigation. The Mamdani algorithm, which is implemented in the MATLAB package, is proposed as a fuzzy inference system. The formalization of the description of the indicators of the irrigation machine is carried out by specifying linguistic variables. The proposed mathematical model can be used in the design of control systems for other robotic agricultural machines.
Estimation of Probability Distributions of Geoacoustic Signal Characteristics
Authors: Gapeev M I , Senkevich Yu I , Lukovenkova O O
Published: November 2021

The paper presents an estimation of probability distributions of geoacoustic signal characteristics. The studied signals have a pulsed nature. The ones have been recording at the geodynamic test site of the IKIR FEB RAS (Kamchatka Peninsula) for more than 20 years. To estimate the distribution of characteristics, such time intervals were determined in which histograms of the distribution did not change. The following characteristics were chosen for the estimation: maximum amplitude, the position of pulse envelope maximum, duration, filling frequency, and pulse-to-pulse interval. The obtained estimates made it possible to develop an empirical model of the geoacoustic emission signal. The model can help to test new and existing algorithms for the processing and analysis of geoacoustic signals. The paper also shows that the formalization of the selected characteristics makes it possible to search for anomalies, including those associated with seismic events, by the characteristic variations.
Investigation Adsorption Process Energy Capacity Reducing Possibility by Composite Adsorbents Implement
Authors: Ripol-Saragosi T , Ripol-Saragosi L
Published: November 2021

The research results presented in the article are devoted to the compressed air adsorption drying processes energy intensity reducing possibilities study. The investigation concerns the new adsorbent – composite. The material is considered as one of the most perspective at the present time. It’s ehergy efficiency is proved comparing traditional adsorbents such as silica gel, alumogel, zeolites, etc. The authors consider the bulk density as one of the factors at the adsorption process energy efficiency increase. The formulas given at the articles allow to calculate the different adsorbents bulk and apparent density, the compressor’s energy efficiency by using different adsorbents at pneumatic schemes, etc.
Development of an Algorithm for Carrying Out Geophysical and Geological Works Using Automated Systems and GIS Technologies
Authors: Dadykin V S , Podobay N V , Elyakova I D , Fedorova E Y
Published: November 2021

During the whole period of existing a modern geological industry, the issues of its computerization have been a priority, both in terms of providing employees of enterprises and organizations with computer equipment, and in terms of arranging information exchange and telecommunications between interacting information agents. It should be noted that there is a correlation between the increasing complexity of mining projects and the need to provide work with more and more developed software and hardware, information technologies, increasing complexity and growing number of software systems used to solve geological problems. The list of enterprises with positive experience in the development and operation of systems and complexes used in geology, geophysics and for subsurface use is also expanding very effectively. We propose the development of an algorithm for conducting geophysical and geological works using automated systems and GIS technologies, aimed at ensuring the rational development of the mineral resource potential of the region and ensuring the stage-by-stage nature of the geological exploration process. The testing was carried out using software product Diafond, which is available at the Russian Federal Geological Fund. This work was financially supported by the grant of the President of the Russian Federation No. MD- 2409.2020.5.
Modeling Conflicts Resulting from Sharing Telecommunication Resource between Antagonistic Control Systems
Authors: Fedorov V Kh , Balenko E G , Starodubtsev Yu I , Vershennik E V
Published: November 2021

Today state-of-the-art communication systems, whilst being limited in resources, use a shared information and telecommunication network to provide integrated communication services; the resources of such a network are split between various control systems, some of which may conflict, resulting in a variety of malware attacks. This paper dwells upon a method for modeling conflicts resulting from sharing a telecommunication resource between antagonistic control systems; the method takes into account the use of such a shared resource (ITCN) and the following processes: data processing by cyber threat intelligence systems, and making decisions on executing MAs upon the elements of conflicting control systems; for each moment of simulation time, the method calculates the current potential of each conflicting system in order to find the average potential degradation time.
Development of the Lower Extremity Exoskeleton Dynamics Model Using in the Task of the Patient Verticalization
Authors: Saypulaev M R , Zuev Yu Yu , Saypulaev G R
Published: November 2021

The object of the study is an exoskeleton of the lower extremities with a rigid structure of the power frame, which has 7 degrees of freedom. The movement of the exoskeleton in the sagittal plane is considered with the assumption of symmetrical movement of the right and left legs. The aim of the study is to develop a mathematical model of the dynamics of the exoskeleton, taking into account the forces of viscous friction in the joints. The equations of motion are obtained under the condition that there is no slippage of the points of contact with the supporting surface. Based on the results of numerical simulation, the control moments were obtained, which must be created by the drives to provide program movement.
Improving the Reliability of the Information and Measurement System of Aviation Surveillance
Authors: Eliseev A V
Published: November 2021

It is shown that various sensors are used to ensure air traffic control in civil aviation, namely: primary and secondary radars, multilateration surveillance systems, automatic dependent surveillance systems of broadcast and contract types, multistatic radars. Based on the analysis of the main disadvantages of the considered systems, it was concluded that the use of multilateration aircraft surveillance systems (MLAT) is promising. The need to improve the reliability of MLAT is noted. The work proposes a method of structural and informational redundancy of MLAT based on the introduction of an additional receiver into its design. It allows to measure the distance to the aircraft using the energy method. The analysis of increasing the reliability of MLAT at various redundancy rates is carried out.
Using of Beylkin Wavelet for Speech Recognition
Authors: Leontiev N A
Published: November 2021

This paper describes the application of the Beylkin wavelet for speech segmentation. The problem of speech segmentation in the Yakut language is that there are segmentation difficulties due to the peculiarities of the language. The use of long vowels and double consonants in the Yakut language complicates the correct segmentation of oral speech. For the analysis, the window method of analyzing the energy of the wavelet signal is used. The experience of using different wavelet functions has shown that it is not always possible to accurately find the segment boundaries in some cases. The Scilab package has a large library of wavelets that allows extensive research into their applications in speech recognition. The results of the study show that there are difficulties due to various reasons, one of which is the presence of double sonorant consonants. The graphs of the analysis of doubled sonorant consonants are given.
Dependence of the Piezoelectric Micropump Operating Mode on Its Geometry
Authors: Nasibullayev I Sh , Nasibullaeva E Sh , Darintsev O V
Published: November 2021

A mathematical and computer axisymmetric models in which periodic oscillations of ring piezoelectric actuators placed on an elastic tube of circular cross-section leads to radial deformations of the tube is constructed. The result of these displacements is a local compression of the microchannel, which leads to changes in its volume and the corresponding pushing of the fluid. If a non-symmetrical oscillation scheme is used, the average fluid flow over the period will be non-zero and the device can be used as a micropump. The aim of the work is a computer study of the geometric features of an axisymmetric piezoelectric micropump, taking into account the processes of heat transfer by a fluid in the channel. The dependence of the average fluid flow rate on the channel parameters and the frequency of oscillations of the piezoelectric actuators is determined by the method of factorial experiment. The parameters preventing heat backflow have been determinate, which makes it possible to use a device for supplying coolant to a microgripper cooling system.
Method for Solving the Problem of Heat Transfer in a Flat Channel
Authors: Eremin A V , Gubareva K V
Published: November 2021

In power engineering, studies related to the distribution of temperatures and velocities in fluids that move, for example, in pipelines or channels, are of theoretical and practical importance. The presented work displays the results of the development of an approximate analytical method for mathematical modeling of the process of heat transfer in laminar flows. By the example of solving the problem of heat transfer in a flat channel with a Couette flow, the main provisions of the method are considered. The combined use of the integral heat balance method and the collocation method made it possible to obtain an analytical solution that is simple in form. The obtained accuracy of solutions depends on the number N of points of the spatial variable at which the original differential equation is exactly satisfied.
Implementation of Power Plants Based on Renewable Energy Sources in the Primorsky Krai
Authors: Chernyavsky A A , Ivanin O A , Shevchenko A L , Zaichenko V M
Published: November 2021

The results of calculations presented in the article show the effectiveness of the transition from diesel power plants using imported fuel to installations using renewable energy sources – solar cells and wind generators. Studies have shown that for Primorsky Krai such a transition is justified, despite significant capital costs, and the payback period for new power plants based on renewable energy sources is about 8 years.
Mathematical Model of Micropolar Lubricant Considering Viscosity-Pressure Dependence
Authors: Morozova A V , Zadorozhnaya N S , Mukutadze M A , Kirishchieva V I
Published: November 2021

In the study, based on the micropolar fluid flow equation for a “thin layer”, the continuity equation, the equation describing the profile of the molten contour of the guide coated with a low-melting metal alloy, and the equation for the mechanical energy dissipation rate, asymptotic and exact self-similar solution has been found for the zero (without considering the melting) and first (considering the melting) approximation of wedge-shaped support with the slider support profile adapted to the friction conditions and the low-melting metal coating of the guide surface. The research has taken into account the pressure dependence of the lubricant rheological properties and the melt having micropolar properties in the laminar flow regime. Analytical dependencies have been obtained for the molten surface profile of the low-melting metal coating of the guide and the field of velocities and pressure for the zero and first approximations. Also, the basic performance characteristics of the friction pair under consideration have been determined: the bearing capacity and the friction force. The impact of parameters determined by the coating melt, adapted to the support profile friction conditions, and the parameter characterizing the pressure dependence of the lubricant viscosity on the bearing capacity and friction force has been estimated.
Ways to Improve Wear Resistance and Damping Properties of Radial Bearings Taking into Account Inertial Forces
Authors: Bagrova V N , Kolobov I A
Published: November 2021

This article considers a radial sliding bearing of infinite length whose moving part consists of the support, the porous layer, and the liquid lubricant. The analysis of the existing design calculation methods for such sliding bearings shows that they are very approximate because they do not consider the inertial forces applied, the electric conductivity of the lubricant, the permeability anisotropy, as well as the impacts of the electric field vector, magnetic induction vector, and incomplete filling of the working gap (pre-accident condition). The authors demonstrate how these factors impact the stable operation of the device facilitating the hydrodynamic regime. The authors find the asymptotic solution for the zero, first, and second approximation taking into account the inertial forces for the “thin layer”. By solving the produced equations using the Gauss-Seidel method, the authors determine the key operating parameters of the friction couple in question: the carrying capacity and the friction force. The authors provide an impact assessment for the parameters characterizing the permeability of the porous coating, the electric conductivity, and viscosity of the lubricant, as well as the length of the loaded area and the impacts of inertial forces on the carrying capacity and the friction force.