bluuebunny/crossref_metadata_2025 huggingface dataset:
A Ni(OH)2 nanosheet array modified with Fe–phytate complex layer as a corrosion resistant catalyst for seawater electrolysis at ampere-level current density
Authors: Song Yanyan , Shi Wenjie , Li Nini , Li Qingyu , Wang Xi-ao , Zhang Xiaoyan , Huang Minghua , Zhang Lixue
Published: November 2024

A corrosion-resistant Ni(OH)2–PA–Fe catalyst was controllably synthesized via a simple spray method to realize highly efficient seawater electrolysis.
Image-based fuzzy logic control for pressure-driven droplet microfluidics as autosampler for multimodal imaging microscopy
Authors: Ott Fabian , Meyer-Zedler Tobias , Schmitt Michael , Popp Jürgen
Published: November 2024

The developed feedback system enables precise positioning and holding of individual droplets. Possible applications include imaging and on demand control of lab-on-a-chip systems.
A multimodal digital microfluidic testing platform for antibody-producing cell lines
Authors: Lant Jeremy T. , Frasheri Jurgen , Kwon Taehong , Tsang Camille M. N. , Li Bingyu B. , Decombe Sheldon , Sklavounos Alexandros A. , Akbari Samin , Wheeler Aaron R.
Published: November 2024

We introduce a novel platform for cell line optimization for mAb production using digital microfluidics. The platform enables testing of cell culture samples in 6–8 μL droplets with semi-automated viability, media pH, and antibody production assays.
Facile one-pot synthesis of a manganese–cerium dual-doped hydroxyapatite nanocatalyst using Phyllanthus emblica extract for photocatalytic degradation of methylene blue dye and catalytic reduction of 4-nitrophenol
Authors: Bharali Linkon , Mazumder Maria Hilaly , Chakraborty Debarati , Kurmi Prakash , Dhar Siddhartha Sankar
Published: November 2024

Novel Mn-Ce/HAp nanocatalyst was fabricated using green extract of Phyllanthus emblica and utilized it for the photodegradation of methylene blue dye and reduction of 4-NP to 4-AP.
Rb1.87Cs1.13B8O13(NO3): a new acentric borate-nitrate with two types of three-dimensional interpenetrating lattices
Authors: Liu Changyou , Liu Xu , Feng Qiuyuan , Hou Ketian , Zhang Bei , Lu Juanjuan
Published: November 2024

A novel Pca21-forming borate-nitrate, with the formula Rb1.87Cs1.13B8O13(NO3) (RCBN), was synthesized. It shows moderate birefringence (0.047@1064 nm), SHG response (0.3 × KDP) values and a short UV cut-off edge (228 nm).
Unveiling the anti-inflammatory potential of organoselenium Schiff bases: computational and in vitro studies
Authors: Shaaban Saad , Yousef Tarek A. , Althikrallah Hanan A , Al-Faiyz Yasair S. , Elghamry Ibrahim , Sharaky Marwa , Alnajjar Radwan , Al-Karmalawy Ahmed A.
Published: November 2024

Computational and in vitro assessments of the anti-inflammatory potential of organoselenium Schiff bases.
Enhancing the activity and stability of Fe/Co-based nitrogen-doped carbon with richer nitrogen and metal-N active sites towards oxygen reduction reactions
Authors: Wu Zeqi , Zhao Zhenlu
Published: November 2024

Based on the nitrogen enrichment and coordination effects with Fe/Co from polydopamine (PDA), Fe/Co-based nitrogen-doped carbon (Fe/Co-NC RN III) was prepared and exhibited good ORR activity and stability.
Multi-crosslinked strong, tough and anti-freezing organohydrogels for flexible sensors
Authors: Wang Jing , Li Longwei , Guo Zi Hao , Pan Chongxiang , Pu Xiong
Published: November 2024

The schematic drawings of temperature are replaced by our own artworks and now we confirm that all of the artwork used in the image is our own.
Cu(ii)-catalyzed synthesis of N-sulfonated quinolin-2(1H)-one-3-carboxamides
Authors: Chen Xue , Fang Shi-Jie , Zhou Quan , Huang Wei , Liu Qiu-Lan , Wang Lei
Published: November 2024

Herein, we present an efficient Cu(ii)-catalyzed cascade synthesis of sulfonated 3-carboxamide quinolin-2-(1H)-ones. Inthis paper, sulfonylhydrazides underwent an unusual N–N bond cleavage and functioned as sulfamide synthons.
Correction: Cu(ii)-Mediated aerobic oxidative synthesis of sulfonated chromeno[4,3-c]pyrazol-4(2H)-ones
Authors: Zhou Quan , Yu Hai-Yan , Zhou Yaqing , Wei Jing-Ru , Wang Lei
Published: November 2024

Correction for ‘Cu(ii)-Mediated aerobic oxidative synthesis of sulfonated chromeno[4,3-c]pyrazol-4(2H)-ones’ by Quan Zhou et al., Org. Biomol. Chem., 2022, 20, 5575–5581, https://doi.org/10.1039/D2OB00639A.
Isomer-driven polymerization, depolymerization, and reconstruction
Authors: Wakefield IV Herbert , Fromel Nicholas J. , Jiang Jennifer , Kevlishvili Ilia , Yao Yunxin , Craig Stephen L. , Kulik Heather J. , Klausen Rebekka S.
Published: November 2024

We report that differences in ring strain enthalpy between cis and trans isomers of sila-cycloheptene provide a driving force for both polymerization and depolymerization via olefin metathesis.
Effects of metal doping on the methanol deep oxidation activity of the Pd/CeO2 monolithic catalyst
Authors: Li Yue , Zhang Jingjing , Lin Yile , Sanwal Piracha , Zhou Lulu , Li Gao , Chen Yongdong
Published: November 2024

The Pd/CeLa, with a complete conversion temperature of 155 °C, shows the best methanol oxidation activity at low temperatures. It is due to the high-valence Pdδ+ (δ > 2) species produced by electron transfer from Pd at the interface to CeLa support.
(BO)2-doped tetrathia[7]helicenes: synthesis and property-change induced by “BO bond inversion”
Authors: Menduti Luigi , Baldoli Clara , Manetto Simone , Villani Claudio , Penconi Marta , Grecchi Sara , Arnaboldi Serena , Mazzeo Giuseppe , Longhi Giovanna , Bolte Michael , Virovets Alexander , Lerner Hans-Wolfram , Wagner Matthias , Licandro Emanuela
Published: November 2024

(BO)2-helicene 2 was prepared and compared to its isomer 1 featuring reverted BO-bonds: spectroscopic and theoretical studies showed as “BO-inversion” is a tool to improve optoelectronic properties.
Synthesis and derivatization of an isomer of an N-heterotriangulene bearing five-, six- and seven-membered rings around the central nitrogen atom
Authors: Chen Xinxin , Wang Weifan , Zhang Gang
Published: November 2024

An isomer of an N-heterotriangulene containing five-, six- and seven-membered rings around the central nitrogen atom was synthesized. It can be further functionalized by condensing with ortho-diamines to afford the π-extended derivatives.
Drug repurposing of fluoroquinolones as anticancer agents in 2023
Authors: Kassab Asmaa E. , Gomaa Rania M. , Gedawy Ehab M.
Published: November 2024

Drug developers are currently focusing on investigating alternative strategies, such as “drug repositioning”, to address issues associated with productivity, regulatory obstacles, and the steadily rising cost of pharmaceuticals.
Wearable threads for monitoring sanitizer quality using dye displacement assay
Authors: Joshi Pratham , Shinde Akhiya , Sudhiram Sukanya , Sarangi Bibhu Ranjan , Mani Naresh Kumar
Published: November 2024

A simple and robust approach integrating threads and permanent markers to detect sanitizer quality based on dye displacement assay.
Regulation of oxidative stress enzymes in Candida auris by Dermaseptin: potential implications for antifungal drug discovery
Authors: Wani Mohmmad Younus , Srivastava Vartika , Saleh Tamer S. , Al-Bogami Abdullah Saad , Aqlan Faisal Mohammed , Ahmad Aijaz
Published: November 2024

Dermaseptin regulates oxidative stress enzymes in Candida auris, inducing oxidative damage and highlighting its potential in antifungal drug discovery.
Foodborne pathogen detection using surface acoustic wave biosensors: a review
Authors: Zeng Yujia , Yuan Rui , Fu Hao , Xu Zhangliang , Wei Song
Published: November 2024

This paper summarizes several attractive surface acoustic wave (SAW) biosensors, including Love-wave sensors, dual-channel SAW sensors, langasite SAW sensors, and SAW syringe filters.
Characterization and enhanced carbon dioxide sensing performance of spin-coated Na- and Li-doped and Co-doped cobalt oxide thin films
Authors: Saad Rana , Abdelkarem Khaled , El Sayed Adel M. , Shaban Mohamed , Ahmed Inas A. , Tammam M. T. , Hamdy Hany
Published: November 2024

Monitoring CO2 levels has become increasingly vital, given the substantial effects of CO2 on human health and the environment.
Sea foam contains hemoglycin from cosmic dust
Authors: McGeoch Julie E. M. , McGeoch Malcolm W.
Published: November 2024

Sea foam is subjected to Folch extraction and mass spectrometry to isolate hemoglycin, an iron-terminated anti-parallel polymer of glycine first found in meteorites. The polymer has elevated isotope levels indicative of an origin in cosmic dust.
Efficient convergent synthesis of 1,3-diazepinone nucleosides by ring-closing metathesis and direct glycosylation
Authors: Hedger Adam K. , Findell Jonathan , Barak Dinesh S. , Schiffer Celia A. , Watts Jonathan K. , Ali Akbar
Published: November 2024

A new and highly efficient ring-closing metathesis-based strategy was developed for the synthesis of the cyclic urea 1,3-diazepinone, presenting significant improvement upon previous methods.
Correction: A safe and efficient synthesis of N-Boc-β3-amino acid methyl esters from α-amino acids: applications in the formal synthesis of sedum alkaloids
Authors: Long Bohua , Ren Lijie , Jiang Mengmeng , Hu Shengquan , Jiang Qianqian , Li Limin , Chen Xuanluan , Wu Zhengzhi
Published: November 2024

Correction for ‘A safe and efficient synthesis of N-Boc-β3-amino acid methyl esters from α-amino acids: applications in the formal synthesis of sedum alkaloids’ by Bohua Long et al., RSC Adv., 2024, 14, 36016–36021, https://doi.org/10.1039/D4RA07506D.
Molecular origins of exciton condensation in van der Waals heterostructure bilayers
Authors: Payne Torres Lillian I. , Schouten Anna O. , Mazziotti David A.
Published: November 2024

A “critical seed” of exciton condensation is found in molecular-scale fragments of van der Waals heterostructure bilayers via the theoretical signature for exciton condensation, a large eigenvalue in the particle-hole reduced density matrix.
Tandem Rh(ii)-catalyzed 1,3-acyloxy migration/intermolecular [2 + 2] cycloaddition of electron-deficient propargylic esters with alkenes and alkynes
Authors: Xu Zurong , Zhu Dong , Wu Rui , Zhu Shifa
Published: November 2024

Herein, we disclosed a tandem Rh(ii)-catalyzed 1,3-acyloxy migration/intermolecular [2 + 2] cycloaddition of electron-deficient propargylic esters with simple alkenes and alkynes, affording various valuable alkylidenecyclobutane/ene scaffolds.
Solid-state organic electrochemical transistors (OECTs) based on gel electrolytes for biosensors and bioelectronics
Authors: Lu Dongdong , Chen Hu
Published: November 2024

A minireview focusing on OECTs for biosensors and bioelectronics applications, highlighting gel electrolytes as effective strategies for enhancing flexibility, adhesiveness, self-healing ability, biocompatibility, and long-term stability of OECTs.
Hole transportation and defect passivation properties at the perovskite/SAHTM interface: the effect of heteroatom groups and alkyl chain lengths in self-assembled phosphonic acid carbazole derivatives
Authors: Ran Xueqin , Zhu Jianbing , Zhang Chen , Yang Lei , Chen Yonghua
Published: November 2024

Modifications of various heteroatom groups were introduced theoretically in self-assembled hole transporting materials (SAHTMs). Enhanced hole transportation and reduced defects at the perovskite/SAHTM interface were anticipated.
Improved voltage and solubility in hybrid non-aqueous redox flow batteries using a molecular 3,4-ethylenedioxythiophene (EDOT) derivative with a stable radical cation state
Authors: Hwang Hee Kyung , Park Yejoo , Yeom Jisang , Ahn Yohan , Khan Yeasin , Lim Jeewoo , Cabanetos Clément , Seo Jung Hwa , Lee Je Seung , Walker Bright
Published: November 2024

A molecular ethylenedioxythiophene (EDOT) derivative is explored in hybrid lithium redox flow batteries. t-Butyl groups prevent polymerization & protolysis, resulting in a reversibly oxidizable molecule with excellent positive-charge-storing ability.
Nano-engineering halide perovskites: towards energy harvesting, nano-plasmonic sensing and photoflexoelectric applications
Authors: Berhe Taame Abraha , Ashebir Etsana Kiros , Su Wei-Nien , Hwang Bing Joe
Published: November 2024

Halide perovskites can be classified as (1) organic inorganic hybrid and (2) inorganic halide perovskites.
Social–Emotional Functioning of Children With Different Hearing Status and Diverse Cultural Background
Authors: Kawar Khaloob , Michael Rinat
Published: November 2024

Purpose:

The study investigated the social–emotional functioning of children with typical hearing and deaf and hard of hearing (D/HH) children from diverse cultural backgrounds in Israel through parental reports.

Method:

A total of 242 parents from both Arabic and Jewish communities participated: 130 were parents of D/HH children and 112 were parents of children with typical hearing. The Strengths and Difficulties Questionnaire and a background questionnaire were used.

Results:

Results revealed increased total difficulties, emotional symptoms, and peer problems as reported by parents of D/HH children. Jewish parents of D/HH children reported greater total difficulties, conduct problems, and peer problems than Arab parents. Significant gender differences were found, with parents of boys reporting higher levels of hyperactivity/inattention and lower prosocial behavior. Among D/HH children, Arab parents reported higher peer problems among hearing aid users compared to cochlear implant users, whereas Jewish parents reported the opposite trend.

Conclusion:

These findings highlight the significant social–emotional challenges faced by D/HH children, particularly in peer interactions, and underscore the need for tailored interventions that consider cultural differences.
Aging monitoring method for IGBT module based on conduction voltage drop in bridge‐arm short‐circuit
Authors: Liu Shiyuan , Zhang Jingwei , Zhao Cui , Liu Kun , He Fangyuan
Published: November 2024

Insulated gate bipolar transistors (IGBTs) serve as the pivotal components within power conversion systems, and given the harsh conditions they endure, evaluating their aging is of paramount importance. Traditional offline aging monitoring method are relatively complex. Based on the conduction voltage drop as the characteristic quantity of IGBT aging, a simpler technique for extracting this parameter is presented, facilitating the assessment of IGBT aging status. Incorporating the working principle of the IGBT bridge‐arm short‐circuit, a conduction voltage drop model has been established. A composite aging electrical parameter is used to eliminate the impact of degradation in the bond wire of the current source device. By engineering a closed‐loop gate drive circuit with adjustable voltage, the short‐circuit current is maintained constant, thereby facilitating the acquisition of a consistent conduction voltage drop. A conduction voltage extraction circuit is proposed, in which a resistance‐capacitance discharging time is equivalent to the conduction voltage drop to replace the analogue‐to‐digital circuit. By decreasing the amount of active zone of the chip in IGBT module for increased conduction voltage drop to simulate aging state, the proposed method with the driving circuit is experimentally validated as feasible and reliable.
Gaia Data Release 3: Spectroscopic binary-star orbital solutions
Authors: Gosset E. , Damerdji Y. , Morel T. , Delchambre L. , Halbwachs J.-L. , Sadowski G. , Pourbaix D. , Sozzetti A. , Panuzzo P. , Arenou F.
Published: November 2024

Context. The Gaia satellite constitutes one of ESA’s cornerstone missions. Being primarily an astrometric space experiment measuring positions, proper motions, and parallaxes for a huge number of stars, it also performs photometric and spectrophotometric observations. Gaia operates a medium-dispersion spectrometer, known as Radial Velocity Spectrometer (RVS), which provides spectra and radial velocity (RV) time series.

Aims. The paper is focussed on the analysis of the RV time series. We fit orbital and trend models, restricting our study to objects of spectral types F-G-K that are brighter than a magnitude of 12, presenting only one single spectrum (SB1).

Methods. Suitable time series were processed and analysed on an object-per-object basis, providing orbital or trend solutions. The results of the various fits were further filtered internally on the basis of several quality measures to discard spurious solutions. The objects with solely a spectroscopic solution were classified in one of the three classes: SB1 (eccentric model), SB1C (circular model), or TrendSB1 (mere trend model).

Results. We detail the methods used in this work and describe the derived parameters and results. After a description of the models considered and the related quality tests of the fit, we detail the internal filtering process aimed at rejecting bad solutions. We also present a full validation of the pipeline. A description of the current content of the catalogue is also provided.

Conclusions. We present the SB1, SB1C, and TrendSB1 spectroscopic solutions contained in the SB subcatalogue, part of the DR3 catalogue. We deliver some 181 327 orbital solutions in class SB1, 202 in class SB1C, and 56 808 in the associated class TrendSB1. This is a first release and the delivered SB subcatalogue could be further tuned and refined. However, the majority of the entries are correct. Thus, this data set constitutes by far the largest set of spectroscopic orbital solutions to be computed.
Forgotten treasures in the HST/FOC UV imaging polarimetric archives of active galactic nuclei
Authors: Barnouin T. , Marin F. , Lopez-Rodriguez E.
Published: November 2024

Context. The Mrk 463 system is known to host two powerful sources that are separated by about 4 kpc, which were both identified as active galactic nuclei (AGN). This makes the Mrk 463 system a unique laboratory for studying the geometry and dynamics of galaxy merging and its relation to AGN duty cycles.

Aims. The eastern nucleus, Mrk 463E, is the brighter of the two and thus a prime target for a polarimetric study. It is classified as a Seyfert 2 galaxy, meaning that high polarization degrees from scattering off electrons and dust in the polar winds are expected.

Methods. In the continuity of our series of papers, we reduced archived and previously unpublished polarization observations obtained with the Faint Object Camera on board the Hubble Space Telescope to obtain a high-resolution near-ultraviolet polarization map of the Mrk 463E nuclei. We coupled this map to near-infrared and X-ray observations to obtain a clear picture of the geometric arrangement of matter around the core of Mrk 463E.

Results. We found that the nucleus location is farther south of the optical peak flux than previously estimated. The strongly polarized conical wind has a half-opening angle of ∼15° and displays three main periods of mass ejection. Its polarization allowed us to estimate the AGN inclination toward the observer (∼55°). Finally, our maps revealed a streamer connecting Mrk 463E and Mrk 463W, with a tentative detection of a large kiloparsec-scale ordered magnetic field connecting both galaxies.

Conclusions. This unpublished observation finally offered more than the original proposal asked for and allowed us to derive tight geometric and dynamical constraints for Mrk 463E. High-resolution radio maps and infrared polarimetry are now necessary to further study the jet and the newly discovered streamer.
Gas thermodynamics meets galaxy kinematics: Joint mass measurements for eROSITA galaxy clusters
Authors: Li Pengfei , Liu Ang , Kluge Matthias , Comparat Johan , Tian Yong , Júlio Mariana P. , Pawlowski Marcel S. , Sanders Jeremy , Bulbul Esra , Schwope Axel , Ghirardini Vittorio , Zhang Xiaoyuan , Emre Bahar Yunus , Ramos-Ceja Miriam E. , Balzer Fabian , Garrel Christian
Published: November 2024

The mass of galaxy clusters is a critical quantity for probing cluster cosmology and testing theories of gravity, but its measurement could be biased, given that assumptions are inevitable in order to make use of any approach. In this paper, we employ and compare two mass proxies for galaxy clusters: thermodynamics of the intracluster medium and kinematics of member galaxies. We selected 22 galaxy clusters from the cluster catalog in the first SRG/eROSITA All-Sky Survey (eRASS1) that have sufficient optical and near-infrared observations. We generated multiband images in the energy range of (0.3, 7) keV for each cluster, and derived their temperature profiles, gas mass profiles, and hydrostatic mass profiles using a parametric approach that does not assume dark matter halo models. With spectroscopically confirmed member galaxies collected from multiple surveys, we numerically solved the spherical Jeans equation for their dynamical mass profiles. Our results quantify the correlation between dynamical mass and the line-of-sight velocity dispersion, log Mdyn = (1.296 ± 0.001)log(σlos2rproj/G)−(3.87 ± 0.23), with a root mean square (rms) scatter of 0.14 dex. We find that the two mass proxies lead to roughly the same total mass, with no observed systematic bias. As such, the σ8 tension is not specific to hydrostatic mass or weak lensing shears, but also appears with galaxy kinematics. Interestingly, the hydrostatic-to-dynamical mass ratios decrease slightly toward large radii, which could possibly be evidence for accreting galaxies in the outskirts. We also compared our hydrostatic masses with the latest weak lensing masses inferred with scaling relations. The comparison shows that the weak lensing mass is significantly higher than our hydrostatic mass by ∼110%. This might explain the significantly larger value of σ8 from the latest measurement using eRASS1 clusters than almost all previous estimates in the literature. Finally, we tested the radial acceleration relation established in disk galaxies. We confirm the missing baryon problem in the inner region of galaxy clusters using three independent mass proxies for the first time. As ongoing and planned surveys are providing deeper X-ray observations and more galaxy spectra for cluster members, we expect to extend the study to cluster outskirts in the near future.
Detection of the lowest mass ratio contact binary in the universe: TYC 3801-1529-1
Authors: Li Kai , Gao Xiang , Guo Di-Fu , Gao Dong-Yang , Chen Xu , Wang Li-Heng , Xin Yu-Xin , Han Yu-Xin , Kim Chun-Hwey , Jeong Min-Ji
Published: November 2024

This paper presents the first analysis of the contact binary TYC 3801-1529-1. We observed four sets of multiple bands complete light curves and one set of radial velocity curve of the primary component. Based on a simultaneous investigation of our observed and TESS light curves and the radial velocity curve, we found that TYC 3801-1529-1 is an extremely low-mass-ratio, medium contact binary with q = 0.0356, with the contribution of the third light at a level of about 10%. Its mass ratio is lower than V1187 Her, making TYC 3801-1529-1 the lowest mass-ratio contact binary ever found in the universe. The light curves observed in 2022 are asymmetric, which is aptly explained by a hot spot on the primary component. A 16-year eclipse timings analysis indicates a secular increase orbital period with a rate of dp/dt = 7.96(±0.35)×10−7 d yr−1. We studied the stability of this target and identified that not only the value of Jspin/Jorb, but also the mass ratio surpass the unstable boundary. Hence, TYC 3801-1529-1 presents a challenge to theoretical research and ought to be considered a progenitor of a contact binary merger.
Explanation of the exceptionally strong timing noise of PSR J0337+1715 by a circum-ternary planet and consequences for gravity tests
Authors: Voisin G. , Cognard I. , Saillenfest M. , Tauris T. M. , Wex N. , Guillemot L. , Theureau G. , Freire P. C. C. , Kramer M.
Published: November 2024

Context. Timing of pulsar PSR J0337+1715 provides a unique opportunity to test the strong equivalence principle (SEP) with a strongly self-gravitating object. This is due to its unique situation in a triple stellar system with two white dwarfs.

Aims. Our previous study suggested the presence of a strong low-frequency residual signal in the timing data, and we set out to model this signal on a longer dataset in order to determine its nature and improve accuracy.

Methods. We considered three models: chromatic red noise, achromatic red noise, and a small planet in a hierarchical orbit with the triple stellar system. These models were implemented in our numerical timing model. We performed Bayesian inference of posterior distributions. Best fits were compared using information-theoretic criteria.

Results. We rule out chromatic red noise from dispersion-measure variations. Achromatic red noise or a planet in Keplerian orbit provide the best fits. If the residual signal is red noise, then it appears exceptionally strong. When assuming the presence of a planet, we obtained a marginal detection of mutual interactions that allowed us to constrain its mass to ∼0.5 MMoon as well as its inclination. The latter is intriguingly coincident with a Kozai resonance. We show that a longer observation span will ultimately lead to a clear signature of the planet model due to its mutual interactions with the triple system. We produce new limits on SEP violation: |Δ|< 1.5 ⋅ 10−6 or |Δ|< 2.3 ⋅ 10−6 at a 95% confidence level under the planet or red-noise hypothesis, respectively. This model dependence emphasises the need for additional data and model selection. As a by-product, we estimated a rather low supernova kick velocity of ∼110 − 125 km/s, strengthening the idea that it is a necessary condition for the formation of pulsar triple systems.
The impact of pianist-controlled engaged mass on piano keystroke dynamics
Authors: Somma Antonio , Roudet Jeanne , Fabre Benoît
Published: November 2024

The conventional methods used to measure and model the dynamics of a piano keystroke typically involve applying force at the key front using mechanical excitation. However, the influence of the actuator mass on the resulting motion and force profile has never been addressed. Conversely, within the realm of piano technique, mechanical excitation occurs through engagement with parts of the pianist’s body, whose mass can vary significantly. Pianists claim to have the ability to adjust the mass they engage at will. We propose a new approach that integrates the pianists’ bodily presence into the mechanical system under examination. By doing so, we aim to reformulate the control parameters associated with piano keystrokes, as typically discussed in scientific literature. This approach yields a simplified model of a pressed keystroke that incorporates the presence of an actuator mass. Through minimally invasive experiments, we observe the relationship between tone volume and driving force, considering levels of inertia comparable to those engaged by pianists through their bodies, with excitation starting at the surface of the key. The results are consistent with our proposed model, highlighting the antagonistic role of total inertia in piano tone production. This approach broadens our understanding of pianists’ control strategies and sheds light on its complex interplay with musical needs in piano performance.
Investigation of the efficiency of grid-connected solar power plant for an individual residential house
Authors: Shilnikov Sergey , Terentyev Pavel , Filatov Dmitrii
Published: November 2024

Solar energy is the most available renewable resource for use in power supply systems for various objects. One of the promising areas is individual residential buildings. The article presents the results of research into the actual efficiency of grid-connected solar power plant for an individual residential house. The main criterion is the volume of generation and quality of electricity. It is shown that in the conditions of the Nizhniy Novgorod region of the Russian federation the effective share of electricity compensation from the grid solar power plant instead of electricity from the centralized network is 33%, the capacity of the solar power plant is 2.4 kw. For greater compensation of electric power it is necessary to use accumulator batteries.
Development of mobile lidar complex for remote sensing of greenhouse gases in the troposphere on the horizontal (inclined) paths
Authors: Nevzorov Alexey , Yakovlev Semen , Sadovnikov Sergey , Nevzorov Aleksey
Published: November 2024

The mobile lidar complex for measuring the spatial distribution of ozone (O3) and methane (CH4) concentrations in the troposphere on horizontal (inclined) sensing paths in the ultraviolet (UV) and infrared (IR) spectral regions is presented. The lidars of the measuring complex operate based on the method of differential absorption and scattering at pairs of wavelengths of 299/341 nm for O3 sensing and 3428.17/3430.75 nm for CH4. A technical description of the mobile lidar complex is given.
Methodology for testing an aircraft with cycloidal propulsors in a wind tunnel
Authors: Dekterev Dmitrii , Finnikov Konstantin , Dekterev Artem , Sentyabov Andrey , Dekterev Aleksandr
Published: November 2024

The article describes a technique that makes possible to compile a minimum required program for testing an aircraft with cycloidal propulsors in a wind tunnel to find a given flight mode. By flight mode we mean a mode in which the lift force corresponds to the mass of the aircraft, the thrust compensates for the drag that occurs at a given speed of the oncoming flow, and the pitch, yaw and roll torques are insignificantly small. An analytical model is described that uses experimental data and CFD modeling to find the flight mode and the iterative steps necessary to determine the correction factors. The use of the described method allowed us to demonstrate the flight modes of the aircraft at speeds of 10, 15 and 20 m/s during wind tunnel tests.
Results of the generalization of studies of wet-steam flows in steam turbine cascades using laser diagnostic systems
Authors: Tishchenko Victor , Tishchenko Alexander , Gribin Vladimir , Popov Vitaly , Gavrilov Ilia , Berdyugin Kirill , Smirnov Alexei , Sokolov Dmitry
Published: November 2024

The description of experimental investigations of wet steam flows in turbine flow path elements (blade cascades) using laser diagnostics system is presented. This technique is used to obtain velocity fields of discrete phase using photos of illuminated tracers moving in the steam flow. PIV and PTV methods are used for this propose. The studies are performed on experimental rig WSC (Wet Steam Circuit) situated at Moscow Power Engineering Institute. Different ways of laser diagnostics systems application are presented. Example of experimental velocity vector field processing and analyses is presented. The way of increasing PIV/PTV methods quality using neural networks is presented.
Energy consumption management in residential construction: Methods and effects
Authors: Uvarova Svetlana , Kiseleva Elena , Smorodina Elena , Belyantseva Oksana
Published: November 2024

The necessity to enhance the energy efficiency of buildings under construction and renovation, in line with the targeted focus on sustainable economic development, requires the development of scientifically grounded tools that allow for decisions to be made at the initial stages of a building’s life cycle, which contribute to reducing energy consumption during the operational phase. This article substantiates digital energy modeling of buildings, technical supervision at all stages of the object’s life cycle, and energy auditing as such tools. The multitude of stakeholders involved in investment projects for residential buildings throughout their life cycle necessitates the creation of methodological foundations for determining and predicting the effects of energy consumption management measures for each stakeholder, considering their specific goals. The methodology proposed in this article for assessing the effects of building energy consumption management for stakeholders takes into account not only the economic effect, which is the direct result of reduced energy consumption and losses but also several accompanying effects, such as environmental, reputational, and social impacts. The calculation of the effect is formalized. The conducted approbation demonstrated the reliability and practical significance of the proposed methodological tools.
Possible sources for biochar production in the south of the Russian Far East
Authors: Nesterova Olga , Brikmans Anastasia , Bovsun Maria , Semal Viktoriia
Published: November 2024

The study investigates the comparative analysis of biochar from vegetable raw materials and paper. The analysis revealed that biochar from the raw materials we studied showed that biochar has an alkaline reaction of the medium, which means it can be used on acidic soils. The study found that according to the content of nitrogen and phosphorus, the studied material can be used on soils as an organic fertilizer. In general, it can be said that the most effective fertilizer, according to preliminary estimates, will be biochar from Ahnfeltia tobuchiensis and a mixture of perennial grasses, due to the high content of nitrogen and phosphorus. The use of biochar from various raw materials sources can become the basis for climate projects and the creation of its own carbon markets in the agricultural sector of the Russian Federation.
Mathematical model of an energy-efficient controller for fuel and energy complex facilities
Authors: Tsarkova Evgenia
Published: November 2024

The paper investigates energy efficiency issues that arise in the operations of the fuel and energy complex within the institutions of the Penal System of the Russian Federation. It focuses on the main consumers of thermal energy, including heat supply systems for industrial and residential facilities. The problems of energy-efficient control of heating devices in the energy sector of the penitentiary department and the main ways of their solution are covered. The methods of designing energy-efficient controllers for increasing the efficiency of energy facilities within the Penitentiary System are considered. The issue of improving energy efficiency is presented in the form of an optimal control problem, for which an analytical solution is developed.
Bifurcation of environmental safety: Science and technology
Authors: Lang Petr
Published: November 2024

The paper analyzes the provisions of the domestic legislative base and legal doctrine on the discussion issues of substantive and essential parameters of the category of environmental safety of the state. The opinions of domestic and foreign authors are studied, an extensive layer of theoretical and applied problems in the field of normative-legal support of the activity of state-public entities to ensure environmental safety, as well as ways to neutralize them in the foreseeable future are presented. Accumulation of the accumulated theoretical and empirical material, combined with the use of modern methods of cybernetic research made it possible for the author of the publication to present a set of measures to modernize the normative-legal parameters of state policy in the field of environmental protection. The theoretical and practical significance of the obtained results is multifaceted, as the substantiated conclusions can be a foundation for further doctrinal developments on auxiliary issues of ensuring environmental safety of the state, as well as in the development of educational and methodological material for disciplines of public-law cycle.
Phase formation in the system Na+,Ca2+,Al3+|| SO42–,HCO3--H2O at 273 K
Authors: Olimjonova N. V. , Muzafarova D. Z. , Jumaev M. T. , Mahmadov H. R. , Davlatshozoda Sh. S. , Nizomov I. M.
Published: November 2024

The article discusses the results of determining possible phase equilibria on geometric images of a five-component mutual water-salt system of sulfates, sodium bicarbonates, calcium and aluminum at 273 K, followed by the construction of its phase complex diagram. The patterns that determine the structure of the phase complex of this system are needed both to obtain scientific data used as reference material, as well as to create optimal conditions for the disposal of liquid waste from industrial aluminum production containing sulfate, bicarbonate salts of sodium, calcium and aluminum. To achieve this goal, we used the translation method, according to which the dimension of the geometric images of the diagram of the original (private) system, when adding a subsequent component to it, increases by one, i.e. the geometric images are transformed. Due to the fact that the studied five-component system consists of five particular four-component systems, the addition of a fifth component to any of them is accompanied by a transformation of the geometric images of all five four-component systems. Transformed geometric images, based on their topological properties, are translated (transferred) to the level of a five-component composition. At the level of a five-component composition, transformed and translated geometric images, observing the Gibbs phase rule, intersect and form geometric images of a given level of component. The study of the phase equilibria of a five-component water-salt mutual system of sulfates, sodium bicarbonates, calcium and aluminum and the construction of its phase complex diagram by the translation method at 273 K showed that it is characterized by the presence of twelve divariant fields, ten monovariant curves and three non-invariant points at this temperature. Based on the data obtained, a complete closed phase diagram of the studied system was constructed for the first time and, for ease of reading, fragmented along the divariant crystallization fields of equilibrium solid phases.
Development of assessing indicator for the technical condition of gearboxes
Authors: Kostomakhin Mikhail , Sayapin Alexander , Pestryakov Efim , Petrishchev Nikolai , Tseiko Mikhail , Kostomakhin Nikolay
Published: November 2024

The efficiency of using energy-intensive tractors in agriculture largely depends on the level of preparation for field work, which depends on the completeness of repair and maintenance activities. For assessmentin-place of the general technical condition of internal combustion engines, various diagnostic tools are used such as motor testers, crankcase gas flow meters, etc. The purpose of the study was to study the state of the issue and justify the need to develop a digital indicator for assessment-in-place of the general technical condition of the hydraulic drive control of the gearbox of energy-intensive tractors. The state of the issue of diagnosing and managing the reliability of agricultural machinery was analyzed in the work. It was found that it is necessary to control the time of the transient process in the hydraulic control system of the gearbox, as well as acceleration when changing gears. It was examined previously produced control and diagnostic equipment, and chose KI-12383 and “Effect-02.01” devices as a prototype for the development of the digital indicator. Modeling as well as design and testing of the prototype were carried out and the possibility of developing the digital indicator was proven, which can be used as a built-in diagnostic tool to justify the need for repair and maintenance of the gearbox. It was concluded that to monitor the general technical condition of the gearbox, a digital indicator was required, which will allow without making changes to the design (K-701, T-150K and their modern analogues) to obtain diagnostic data to justify repair and maintenance activities in order to reduce the risk of failures III complexity groups in the process of field work.
Simulation of heat transfer process in absorber channels
Authors: Nigmatov Ulugbek , Kuchkarov Akmaljon
Published: November 2024

This article describes a mathematical model of heat transfer in absorber channels developed using the «Comsol Multiphysics 5.6. program». The results are presented for determining the longitudinal flow velocity at various sections of the flow channel, heat distribution over time, as well as the heat distribution isoline and isotherm. Developed on the basis of the program «Comsol Multiphysics 5.6.» a simulation model of heat transfer from a photovoltaic battery to a heat absorber can be used to calculate heat and power supply systems. The use of a simulation model in the design of a heat and power supply system makes it possible to reduce the consumption of heat and electricity.
Justification of the impact of digitalization in housing and utilities sector on reducing energy consumption in residential buildings
Authors: Uvarova Svetlana , Savvina Irina , Ovsiannikov Andrei , Bolgov Vladimir
Published: November 2024

Accurate accounting of energy consumption and transparency in the calculation of housing and communal services are important incentives for property users to implement energy-saving measures. Ensuring the reliability of accounting and calculations, as well as reducing energy losses and emergency situations in the provision of energy supply and heating services, can be achieved through a comprehensive approach to the digitalization of the housing and utilities sector (HUS). Digitalization addresses the current problem of conflicting interests among various stakeholders in the HUS field and eliminates distortions of information during communication processes. This article substantiates the influence of digitalization on the efficiency of HUS operations and energy supply services while examining factors that enhance the motivation of key stakeholders to ensure energy efficiency. Through quantitative analysis, the economic viability of acquiring properties with high energy efficiency for consumers of housing and communal services is demonstrated, making such investments advantageous when assessing total cost of ownership.
The influence of porous medium and temperature regime on the formation and gas composition in hydrates of multicomponent gas mixtures
Authors: Ivanova Izabella , Portnyagin Albert , Kalacheva Liudmila , Ivanov Viktor , Bubnova Alla , Argunova Kira
Published: November 2024

The relevance of the study of multicomponent gas mixtures hydrate formation in porous media is due to the widespread occurrence of gas hydrates on the shelf of seas and continents, which requires experimental work to study the effect of a porous medium on the distribution of natural gas components between the gas and hydrate phases in order to understand the processes of hydrate deposit formation. Natural gas from the Srednevilyui field was used to obtain hydrates, in which the sum of C2-C4 homologues is 7.08 mol%. The object of the study was hydrates of this gas obtained in bidispersed quartz sand with a humidity of 15%. Phase transitions during cooling and heating of the «natural gas - sand – water» system were studied by differential thermal analysis. The experiments were conducted in two modes of system cooling: the first mode up to 270.5 K, the second mode up to 279 K. Analysis of the gas composition in the hydrate was determined by gas adsorption chromatography. It was found that in a porous medium natural gas forms a mixture of hydrates with cubic structure sI (methane hydrate) and sII (gas hydrate with a higher content of hydrocarbons C2-C4 (18.73 mol.)), and, as experiments have shown, this mixture can be thermodynamically separated. Based on the conducted study, it was concluded that when gas migrates through the thickness of sedimentary rocks in the area of high temperatures at depth, a deposit of hydrates with a high content of hydrocarbons C2-C4 can be formed, and closer to the surface, where the temperature of the rock decreases, methane hydrate can accumulate.
Algorithm for determining the gas flow rate by the half-division method for pressure measurements in hydrate formation in a well
Authors: Borisova Natalya N. , Rozhin Igor I. , Ivanov Gavril I.
Published: November 2024

Previously, the algorithm for the inverse problem for determining the dynamics of mass flow rate changes in the systems of natural gas production and transportation by measuring the outlet pressure was generalized to the case of hydrate formation in the main gas pipeline and in the well. In this research the new algorithm based on the method of half division (bisection, dichotomy), which has unconditional convergence, is presented. In the process of solving the problem of formation and deposition of gas hydrates on the pipe walls, the dynamics of gas pressure and temperature changes, as well as the flowing section along the length of the well are calculated. Comparison of the calculation results showed that at constant bottomhole pressure the realization of this algorithm, unlike the previously proposed one, leads to an increase in the duration of the process of complete plugging of the well with hydrates and, accordingly, to an increase in the total amount of extracted gas.
Canonical transformations of linear Hamiltonian systems
Authors: Titova Tatiana
Published: November 2024

In this paper we consider the linear Hamiltonian systems of differential equations. We explore the normalization of a non-singular Hamiltonian matrix. We solve a system of matrix equations to find the generating function of the canonical transformation. In various cases we obtain the solution of the system of matrix equations. We get the solution of the algebraic matrix Riccati equation under certain conditions. Some properties of the Hamiltonian matrix have been proven. We get the normal form of a non-singular Hamiltonian matrix of order 4. We obtain the new method of normalization of the quadratic Hamiltonian. With this method we can investigate the stability of solutions of Hamiltonian systems.
Inhibitive behaviour of Gum Arabic on corrosion process of pipeline steel in acidic environment
Authors: Khair Tahar , Abakumova Yuliya , Zueva Olga
Published: November 2024

Pipeline steel is highly susceptible to corrosion in acidic environments, requiring the use of inhibitors. Gum Arabic (GA), consisting of branched complex polysaccharide chains, exhibits a good inhibiting effect on the surface of mild steel in various acidic corrosive media. In this paper, the corrosion of API 5L X60 pipeline steel in 1 M HCl solutions and the possibility of its reduction due to the use of GA were experimentally studied. Mass loss, X-ray diffraction, and potentiostatic methods were employed to study the inhibition effect. It was shown that the use of GA as an inhibitor reduces the corrosion rate in units of penetration from 1.17 to 0.226 mm/year, i.e. more than 5 times. The calculated inhibitor efficiency equal to 93% also indicates that GA in concentration 2g/l is a good inhibitor for API 5L X60 pipeline steel in 1 M HCl. The potentiostatic polarization data reveal that the inhibitor affects both cathodic and anodic processes, i.e. it acts in a mixed manner. Optical microscopic examination confirmed the results obtained by X-ray diffraction and showed that the presence of GA increases the resistance of pipeline steel to pitting corrosion.
Review of gas-liquid reactor designs and approaches to efficiency assessment
Authors: Ponikarov Artem , Salin Alexey
Published: November 2024

The paper provides a brief overview of the reaction devices used in the chemical industry and indicates the main difficulties and limitations that arise in the design and modernization of industrial gas-liquid reactors. It is noted that it is possible to most accurately describe the hydrodynamics of the flow, predict the profiles of concentrations, temperatures, reaction rates and various diffusion effects inside the apparatus for such types of reactors as tubular or piston reactors. A comparative analysis of gas-liquid reactor designs is presented, and the use of a general efficiency factor is proposed to analyze the efficiency of reactions.