bluuebunny/crossref_metadata_2025 huggingface dataset:
From the experience of Managing the Departmental Staff (using the example of the Philosophy Department of State Fire Academy of EMERCOM of Russia)
Authors:   State Fire Academy of EMERCOM of Russia, SVIRIDOVA Natalya V. , DYACHENKO Natalia V. ,   State Fire Academy of EMERCOM of Russia
Published: October 2023

This article is dedicated to analyzing the peculiarities of management experience in leading the humanitarian Philosophy Department within a military university, viewed through the lens of the department's history of management by philosophers E. A. Baller, Y. Y. Zlotnikov, and V. N. Lipsky. Various models of organization have enabled the department to adapt to changing historical circumstances and achieve its educational and developmental objectives. The article is intended for post graduate students, teachers, and administrative staff.
River fire fleet of Hungary: history of creation, equipment, practical application
Authors:   National University of Public Service, HORVATH Galina W. , BERKI Imre ,   Budapest Disaster Central Museum, BLESZITY Janos ,   National University of Public Service
Published: October 2023

The authors introduce the history of the fire fleet of Hungary and analyze the experience and possibilities of using fire boats nowadays. The peculiarity of Hungary is the lack of sea access because of the country's geographical position. However, shipping and transportation via the most important waters – the Danube, the Tisza and Lake Balaton – necessitate the use of fire service vessels, rescue ships and boats.
Looking at the “Inverse” in dermatology
Authors: Bains Pooja
Published: October 2023

The predilection of skin disorders for characteristic sites and awareness of these sites is very important for clinical diagnosis. However, certain subtypes of common dermatological conditions can involve sites opposite to that of the classical presentation. These subtypes are named using the prefix “inverse” or the suffix “inversus/inversa” in the literature. These variants may pose a diagnostic challenge to residents and knowledge of the various “inverse” dermatological conditions and phenomena in the literature is of great significance.
Interdisciplinary Discourse and Improvement of Scientometric Indicators as Trends in the Development of the “Bibliotekovedenie” Journal
Authors: Volkhonskaya Elena N. , Nikonorova Ekaterina V. , Shibaeva Ekaterina A.
Published: October 2023

The article presents an overview of the meeting of the Editorial Council and the Editorial Board of the “Bibliotekovedenie” journal, held on May 17, 2023 at the Russian State Library. Changes in the place and status of a scientific specialty “5.10.4. Library science, bibliography, bibliology” in the nomenclature of the Higher Attestation Commission (HAC) led to the need to revise the content of the policy of forming the scientific content of the journal in the direction of strengthening the interdisciplinary synthesis of the specialty with the humanities and social sciences. At the same time, the development of a domestic system of scientometric evaluation of journals, adequate to modern needs and based on the realities and traditions of Russian education and science, as well as organizational innovations of the HAC concerning the activities of expert and dissertation councils, require rethinking the ways and formats of content submission, approaches to the selection of authors of the publication and their qualifications. The interdependence of these trends necessitates the analysis of their components and discussion by experts of the strategy and tactics of the editorial policy of the “Bibliotekovedenie” journal for the period up to 2030.

The article identifies the main scientific directions, interdisciplinary synthesis with which will not only significantly enrich library science, but also help to reveal its trends in accordance with the request of the current stage of society development.

The expansion of the research field determined by the decision of the HAC actualized the need for a deep cultural understanding of library science, bibliography and book studies, as well as the development of appropriate methodology. The realities of modern life urgently require the inclusion of a geopolitical aspect in the research space of library science, which contributes to the substantiation of the importance of the library as the main institution of cultural identity and the preservation of the written heritage of the peoples of Russia and the world. The role of the journal in the development of scientific communications, strengthening regional ties and supporting library education in Russia was also noted.

The results of the discussion will form the basis of the editorial policy of the journal and will be used in the activities of the editorial board.
Museum Tourism in the Post-Pandemic Period: Problems and Prospects of Development
Authors: Karimova Guzel R. , Idrisova Rimma R.
Published: October 2023

The purpose of this paper is to identify modern forms and methods of interaction between a museum and a tourist visitor in new socio-cultural and economic contexts. Museum as a socio-cultural institution is subject to changes occurring in society and reflects in its activities those rules, demands and values that are relevant for a particular period of history. The spread of market relations in the socio-cultural sphere and the processes of digitalization, accelerated during the COVID-19 pandemic, are directly reflected in the activities of museums. Today, the museum is transforming from a creator and interpreter of scientific knowledge and a guardian of cultural values into an industry that creates a special environment for visitors. Reorientation towards the individual visitor as the main consumer of the museum tourism product poses new issues and challenges for museums. Thus, in the context of individualization of consumer demand, the issue of “including” the museum in the economy of impressions with its emphasis on emotional information, personal experiences of a person and creation of his/her personal experience becomes relevant. Within the framework of the communication approach, the authors of the article investigate the practices of using the basic principles of the impression economy to create a competitive product and build a dialogue between the tourist and the museum on its basis. The latter becomes important in the light of the formation of the visitor’s loyalty to the cultural identity of the city and the region where the museum is located. The application of the system approach allowed to identify general and private practices of museum service in the conditions of a new model of consumption, oriented to meet the increasing demands of the individual tourist. The materials of the article can not only be used in the theoretical and applied activities of museums, but also serve as an analytical basis for regional and municipal state structures in the development of effective programmes and strategies for tourism development.
Research of the Phenomenon of Animalistic Art in the Works of Foreign and Russian Authors
Authors: Portnova Irina V.
Published: October 2023

The article considers animalistic art as a significant historical and artistic phenomenon, which has become a field of research of foreign and Russian authors. The article analyses important questions concerning the specificity of animalistics and related reflections of world outlook. The author discusses moral issues, asks the question about the role of animals in human history, notes the negative results of the consumerist attitude of man to wildlife and, in this regard, the need for a positive and careful attitude to it. The reader’s attention is drawn to animalistic art as a fertile sphere of influence on human feelings and thoughts, especially in the era of global change. The position of the artist, researcher, looking at and studying the world of living nature is revealed. In this aspect the historical stratum of separate epochs is emphasized, in which the figurative nature of animals and in it the qualities of iconicity, symbol as identifying, concentrated meanings are vividly revealed. The first group of questions considers animalistic art from an educational point of view, allowing us to look at the images of animals and birds from the position of a scholar, study. The second group is related to the method of work of the animalist artist, revealing the peculiarities of the genre. The worldview aspect, determined by the artists’ views on the animal world, is inseparable from the pictorial aspect, i.e. the embodiment of animals and birds in the artistic image. This aspect also implies a conversation about the specificity of animalistics, which in the works of Russian researchers found a clear and precise expression. The relevance of the topic is denoted by the importance of talking about the problems of ecology, which have acquired a pronounced character in the modern world. This universal concept of preservation of the natural world, which has become universal, has opened a new layer of significance of animalistic art. At the present stage, when the main principle — the relationship between man and nature — is being reassessed, the reference to the world of animals, including in the historical and artistic aspect, acquires high significance.
Uranium Deposits Capped by Permafrost Seen as Natural Analogues of a Geological Repository Considering the Upcoming Climate Cooling Period
Authors:   Institute of Geology of Ore Deposits, Petrography, Mineralogy, and Geochemistry of the Russian Academy of Sciences, Kochkin B. T.
Published: October 2023

The article evaluates the conditions at the site proposed for a geological radioactive waste (RW) disposal facility (DGR) considering the scenario of the upcoming climate cooling. The evaluation is based on the analogy method with the comparison made against modern conditions explored at uranium deposits confined to the permafrost zone. The analogy is based on modern hydrogeological data from the Transbaikalia deposits explored using the underground borehole leaching method. This method yields no significant disturbance of the groundwater flow patterns. The study provides comparative analysis of climatic, geological and hydrogeological characteristics of the DGR siting area in the Krasnoyarsk Territory and those of uranium deposits in Transbaikalia. The limitations of this method have been validated. The paper highlights the main characteristics of groundwater flows in sub-permafrost aquifers. The results obtained may prove to be helpful in the development of models demonstrating radionuclide transport from the DGR developed at the Yeniseiskiy site.
Near and Far Fields of a Radioactive Waste Disposal Facilities: Approaches to their Modeling Based on the GeRa Software
Authors:   Nuclear Safety Institute of the Russian Academy of Sciences, Suskin V. V. , Kapyrin I. V. ,   Nuclear Safety Institute of the Russian Academy of Sciences, Boldyrev K. A. ,   Nuclear Safety Institute of the Russian Academy of Sciences
Published: October 2023

The study focuses on the safety assessment of near-surface radioactive waste disposal facilities (NSDF) based on the numerical simulation of radionuclide transport in the near field via groundwater flow and mass transport processes using the GeRa software. It also evaluates the methods that may provide near and far field model coupling seeking to arrange a sound safety assessment process. The study specifically focuses on the degradation of the underlying concrete safety barrier indicated through a reduced radionuclide absorption capacity. The study provides calculations for those radionuclides that are typically found in the radioactive waste subject to disposal in deep disposal facilities. The findings evidence some fundamental difference in the activity-yield curves associated with the sorption properties, changes in the barrier properties and the half-lifes of the modelled radionuclides.
Retrospective Analysis of Advancements in the Processing of Accumulated HLW Generated by PA Mayak’s Radiochemical Production Facilities
Authors:   FSUE “PА “Mayak”, Kozlov P. V. , Logunov M. V. ,   FSUE “PА “Mayak”, Remizov M. B. ,   FSUE “PА “Mayak”, Shaidullin S. M. ,   FSUE “PА “Mayak”, Lukin S. A. ,   FSUE “PА “Mayak”, Zubrilovsky E. N. ,   FSUE “PА “Mayak”
Published: October 2023

The article overviews the research implemented at PA Mayak from 1986 to 2021 to develop a method enabling the processing of heterogeneous alkaline HLW. It presents relevant flow charts developed under this research, the reasoning behind them and their evolution stages. The study reflects the broad spectrum of research performed and the scaling-up experience associated with the implemented experiments. The study demonstrates the need for further optimization of the flow chart adopted in the designs of a new vitrification complex to reduce the volume of generated solid Class 1 radioactive waste forms and to increase the processing capacity.
Synthesis and Leaching of Boroncontaining RW Glasses under Deep Disposal Conditions
Authors:   А. N. Frumkin Institute of Physical Chemistry and Electrochemistry of the Russian Academy of Sciences, Martynov K. V. , Andryushchenko N. D. ,   А. N. Frumkin Institute of Physical Chemistry and Electrochemistry of the Russian Academy of Sciences, Nekrasov A. N. ,   D. S. Korzhinsky Institute of Experimental Mineralogy of the Russian Academy of Sciences, Zakharova E. V. ,   А. N. Frumkin Institute of Physical Chemistry and Electrochemistry of the Russian Academy of Sciences
Published: October 2023

The study focuses on the synthesis and characterization of three boron-containing glasses, namely, two borosilicate glasses and one borophosphate glass containing mockup RW elements (Se, Sr, Mo, Cs, La, U, etc.) and radionuclides (99Tc, 239Pu, 241Am). It explores the glass-forming elements (Li, B, Na, Si, P, etc.), mockup RW and radionuclides and their leaching from the synthesized glasses in model underground water assuming the presence of barrier bentonite at temperatures of 25, 90 and 150°C. The study evaluates the changes in the elemental composition and density of the leached layer formed upon incongruent dissolution of glasses, as well as the time-dependent changes in the element concentrations of the leachates assuming different temperatures. For boron-containing glasses, it presents the evaluated concentrations of leachate saturation with glass-forming and RW elements under deep disposal conditions. These findings can be used in experimental and computational modeling of radionuclide transport under deep RW disposal conditions.
FSUE Radon’s Experience in the Conditioning of Spent Radioactive Ion Exchange Resins from the Kalinin NPP
Authors:   Research and Production Complex — Sergiev Posad Branch of the Federal State Unitary Enterprise “Joint Ecological-Technological and Research Center for Disposal of Radioactive Waste and Environmental Protection”, Ostashkina E. E. , Savkin A. E. ,   Research and Production Complex — Sergiev Posad Branch of the Federal State Unitary Enterprise “Joint Ecological-Technological and Research Center for Disposal of Radioactive Waste and Environmental Protection”, Slastennikov Yu. T. ,   Research and Production Complex — Sergiev Posad Branch of the Federal State Unitary Enterprise “Joint Ecological-Technological and Research Center for Disposal of Radioactive Waste and Environmental Protection”
Published: October 2023

The paper discusses the practice applied by FSUE Radon, namely, by the NPK — Sergiev Posad branch to the conditioning of spent ion exchange resins from the Kalinin NPP: they are immobilized within a polymer waste form using a purposely designed and manufactured pilot unit. Based on the laboratory and methodological capacities of the enterprises, the study demonstrates the compliance of the obtained polymer compound and the waste packages with relevant quality indicators and acceptance criteria provided for by the regulatory requirements.
Radionuclide Composition of Solid Radioactive Waste from Conversion Production
Authors:   Ural Federal University named after the First President of Russia B. N. Yeltsin, Semenishchev V. S. , Fomin A. V. ,   Ural Federal University named after the First President of Russia B. N. Yeltsin, Kulyashova E. N. ,   Ural Federal University named after the First President of Russia B. N. Yeltsin, Skripchenko S. Yu. ,   Ural Federal University named after the First President of Russia B. N. Yeltsin, Titova S. M. ,   Ural Federal University named after the First President of Russia B. N. Yeltsin, Nalivaiko K. A. ,   Ural Federal University named after the First President of Russia B. N. Yeltsin, Polyansky A. I. ,   SC “Chepetsky Mechanical Plant”
Published: October 2023

The paper overviews the study on the radionuclide composition of solid radioactive waste (RW) held in a near-surface storage facility at a conversion production site. The total α- and β-activity of the waste ranges from 1.2 to 1,250 kBq/kg and from 1.1 to 560 kBq/kg respectively. Three radioactive waste categories have been identified: those with the predominance of 226Ra in combination with short-lived daughter decay products (specific activity of up to 100 kBq/kg); waste with a predominant content of 238U in equilibrium with 234Th, 234Pa (specific activity of up to 30 kBq/kg); waste with a predominance of 210Pb in equilibrium with 210Bi and 210Po (specific activity of 70 kBq/kg). The increased total alpha activity level is explained by 230Th found in the waste. At low 226Ra activities, one can focus on the total alpha activity levels to identify areas with possible high 210Po and 230Th activities. Most of the waste inventory contains uranium with its isotopic composition being similar to the natural one.
Preliminary Assessment of Engineered Barrier Parameters under DGR Concept with Horizontal Orientation of RW Packages in Copper Coated Containers
Authors:   Nuclear Safety Institute of the Russian Academy of Sciences, Bogatov S. A. , Drobyshevsky N. I. ,   Nuclear Safety Institute of the Russian Academy of Sciences, Krupskaya V. V. ,   Institute of Geology of Ore Deposits, Petrography, Mineralogy and Geochemistry of the Russian Academy of Sciences, Zakusin S. V. ,   Institute of Geology of Ore Deposits, Petrography, Mineralogy and Geochemistry of the Russian Academy of Sciences, Lekhov V. A. ,   Lomonosov Moscow State University
Published: October 2023

The paper discusses a DGR concept providing for heat-generating radioactive waste (RW) disposal in relatively thinwalled steel containers with a copper coating in packages of compacted bentonite blocks installed into horizontal drifts. The study assumes that this DGR layout should provide safe disposal of historical RW Class 1 with relatively low activity and heat generation levels. The proposed concept imposes appropriate restrictions on the bentonite buffer, among which the paper quantitatively considers the thickness varying depending on the residual RW heat release, the minimum bulk density, as well as the content and type of montmorillonite. For further assessment purposes, the paper proposes to consider bentonite blocks made of compacted bentonite from Russian deposits with a predominant content of sodium montmorillonite characterized with minimum required bulk density. The authors also proposed to fill the gaps between RW packages made of compacted bentonite and drifts with pellets. Such bentonite pellets should have maximum achievable bulk density and a predominant content of calcium montmorillonite.
On Design Options Providing the Management of Radioactive Waste Class 1 during DGR Establishment and Operation
Authors:   National Operator for Radioactive Waste management FSUE, Beygul V. P.
Published: October 2023

The article focuses on design options proposed for radioactive waste Class 1 (RW-1) transportation and horizontal disposal in DGR using corrosion-resistant overpacks or packages. Since canisters with RW-1 are going to be shipped from the PA Mayak site in TUK-108/r, the article suggests that a special Pick Up and Packaging Station can be arranged to provide RW-1 packaging in accordance with the DGR waste acceptance criteria for disposal. It also considers the proposals on the fabrication of non-returnable packages and their transportation from the Pick Up and Packaging Station to the horizontal RW disposal compartment. The article presents the proposed compartment layout. It provides preliminary estimates regarding possible RW-1 and RW-2 disposal volumes assuming the concept of horizontal RW-1 disposal in the DGR.
Alles richtig – nichts verstanden?
Authors: Bärtsch Amadeus , Marti Lorenz
Published: October 2023

This article presents ideas from our educational practice in chemistry teaching, focusing on understanding rather than just learning by heart. We recommend always asking students to justify statements, to use chemical formulae as a starting point and aid to reasoning, and to require as little factual knowledge as possible. Because tasks with calculations, formulae and reaction equations can be solved in a recipe-like manner, they should be supplemented with comprehension questions. If students describe processes with sketches at model level and formulate explanations in their own words, it becomes particularly clear whether they have understood the concept.
Processable crosslinked terpolymers made from elemental sulfur with wide range of thermal and mechanical properties
Authors: Yan Peiyao , Wang Haoran , Dodd Liam James , Hasell Tom
Published: October 2023

Inverse vulcanization has emerged as a popular strategy for transforming the waste material, elemental sulfur, into functional polymers with high sulfur content (>50 wt.%, normally). Inverse vulcanized polymers are intrinsically processable and recyclable, and have been demonstrated as promising for applications in many fields. However, the mechanical properties of inverse vulcanized polymers are currently underdeveloped. If this kind of material is to be widely used in some scenarios to replace some traditional plastics, it is necessary to make them with appropriate thermal and mechanical properties that meet basic application requirements. Here, we report a series of terpolymers copolymerized from two distinct organic comonomers and elemental sulfur to obtain polymers with a wide range of glass transition temperatures (-43 °C to 45 °C) that exhibit good mechanical properties, by blending crosslinkers with varying feed monomer ratio and chain length of linear sections, which expands the application opportunities of inverse vulcanization.
Nucleoside Phosphorylases Make N7-Xanthosine, the “Non-native” Regioisomer of Xanthosine
Authors: Westarp Sarah , Brandt Felix , Neumair Lena , Betz Christina , Dagane Amin , Kemper Sebastian , Jacob Christoph R. , Neubauer Peter , Kurreck Anke , Kaspar Felix
Published: October 2023

Modern, highly evolved, nucleoside-processing enzymes are known to exhibit perfect regioselectivity over the glycosylation of purine nucleobases at N9. We herein report an exception to this paradigm. Wild-type nucleoside phosphorylases also furnish N7- xanthosine, the “non-native” ribosylation regioisomer of xanthosine. This unusual nucleoside possesses several atypical physicochemical properties such as redshifted absorption spectra, a high equilibrium constant of phosphorolysis and low acidity. Ultimately, the biosynthesis of this previously unknown natural product illustrates how even highly evolved, essential enzymes from the primary metabolism are imperfect catalysts.
Unveiling nanoscale heterogeneities at the bias-dependent Gold-Electrolyte Interface
Authors: Antony Leo Sahaya Daphne , Monin Loriane , Aarts Mark , Alarcon Llado Esther
Published: October 2023

Electrified solid-liquid interfaces are extremely complex and dynamic, affecting both dynamics and selectivity of reaction pathways at electrochemical interfaces. Enabling access to the structure and arrangement of interfacial water in-situ with nanoscale resolution is essential to develop efficient electrocatalysts. Here, we probe the solidliquid interfacial energy of a polycrystalline Au(111) electrode in neutral aqueous electrolyte, through in-situ electrochemical atomic force microscopy (EC-AFM). We acquire potential-dependent maps of the local interfacial adhesion forces, which we associate to the formation energy of the electric double layer. We observe nanoscale in-homogeneities of interfacial adhesion force across the entire map area, indicating local differences in the ordering of solvent/ions at the interface. Anion adsorption has a clear influence on the observed interfacial adhesion forces. Strikingly, the adhesion forces exhibit potential-dependent hysteresis, which depends on the local gold grain curvature. Our findings on a model electrode extend the use of scanning probe microscopy to gain insights on the local molecular arrangement of the solid-liquid interface in-situ which will be relevant for the study of any electrocatalyst.
Photochemically driven peptide formation in supersaturated aerosol droplets
Authors: Logozzo Alexander , Vennes Benjamin , Kaur Kohli Ravleen , Davies James , Castillo-Pazos Durbis , Li Chao-Jun , Neish Catherine , Preston Thomas
Published: October 2023

The condensation of amino acids into peptides plays a crucial role in protein synthesis and is thus essential for understanding the origins of life. However, the spontaneous formation of peptides from amino acids in bulk aqueous media is energetically unfavorable, posing a challenge for elucidating plausible abiotic mechanisms. In this study, we investigate the formation of amide bonds between amino acids within highly supersaturated aerosol droplets containing dicyandiamide (DCD), a cyanide derivative potentially present on primordial Earth. Metastable states, i.e. supersaturation, within individual micron-sized droplets are studied using both an optical trap and a linear quadrupole electrodynamic balance. When irradiated with intense visible light, amide bond formation is observed to occur and can be monitored using vibrational bands in Raman spectra. The reaction rate is found to be strongly influenced by droplet size and kinetic modelling suggests that it is driven by the photochemical product of a DCD self-reaction. Our results highlight the potential of atmospheric aerosol particles as reaction environments for peptide synthesis and have potential implications for the prebiotic chemistry of early Earth.
A multiple-fidelity Method for Accurate Simulation of MoS 2 Properties Using JAX-ReaxFF and Neural Network Potentials
Authors: Wang Kehan , Xu Longkun , Shao Wei , Jin Haishun , Wang Qiang , Ma Ming
Published: October 2023

Reactive force field (ReaxFF) is one of the most commonly used force field to model the chemical reactions on atomic level. Recently, JAX-ReaxFF, combined with auto- matic differentiation, has been used to efficiently parameterize ReaxFF. However, pre- dicted properties using parameterized ReaxFF may be inaccurate due to the inductive bias of its analytical formula. While neural network-based potentials (NNPs) trained on density functional theory (DFT)-labeled data offer a more accurate method, it re- quires a large amount of training data to be trained from scratch. To overcome these issues, we present a multiple-fidelity method that combines JAX-ReaxFF and NNP, and apply the method on MoS 2 , a promising two-dimensional (2D) semiconductor for flexible electronics due to its excellent mechanical, optical, and electronic properties. By optimizing ReaxFF for MoS 2 and incorporating implicit prior physical information in the functional forms, we show that ReaxFF can serve as a cost-effective way to generate pretraining data, facilitating more accurate simulations of MoS 2 properties, such as the convex hull diagram, sulfur vacancy formation, and interaction with S 8 using SchNet. Moreover, in the Mo-S-H multi-element system, the pretraining strat- egy can reduce root-mean-square errors(RMSE) of energy by 20%. This approach can be extended to a wide variety of material systems, accelerating their computational research.
Hydrodeoxygenation and hydrodenitrogenation of n-hexadecanamide over Pt catalysts: effect of the support
Authors: Verkama Emma , Albersberger Sylvia , Arandia Aitor , Meinander Kristoffer , Tiitta Marja , Karinen Reetta , Puurunen Riikka L.
Published: October 2023

Efficient catalysts for simultaneous hydrodeoxygenation (HDO) and hydrodenitrogenation (HDN) are needed for the production of renewable fuels. In this study, Pt catalysts supported on SiO2, ɣ-Al2O3, SiO2-Al2O3, ZrO2, CeO2-ZrO2, Nb2O5, and TiO2 were studied for the hydrotreatment of n-hexadecanamide (C16 amide) to n-paraffins at 300 °C and 80 bar H2. The catalysts favored HDO over HDN, and the initial differences in the nitrogen removal level were smaller than the differences in the oxygen removal level. The Lewis acid properties of the support influenced the initial C16 amide conversion route and HDO activity, which was reflected in the reaction network and condensation reaction selectivity of the catalysts. Pt/Nb2O5 and Pt/TiO2, with intermediate strength Lewis acid sites, initially favored the HDO of C16 amide to nitrogen-containing compounds. In contrast, the other catalysts converted C16 amide to oxygen- and nitrogen-containing compounds with similar selectivity. The HDO of the oxygen-containing compounds proceeded more efficiently on the Pt catalysts supported on oxides with weak Lewis acid sites (Pt/ZrO2, Pt/CeO2-ZrO2) than on the irreducible oxides with strong or no Lewis acid sites (Pt/ɣ-Al2O3, Pt/SiO2-Al2O3, Pt/SiO2). As the presence of oxygen-containing compounds suppressed HDN activity, the catalysts with the highest HDO activity eventually gave the highest paraffin yield, regardless of which oxygen removal pathway was favored.
Counting electrons in electrides
Authors: Weaver Samuel , Sundberg Jack , Slamowitz Connor , Radomsky Rebecca , Lanetti Matthew , McRae Lauren , Warren Scott
Published: October 2023

The wave nature of electrons makes the quantification of charge fundamentally challenging. In complex materials like electrides, this challenge is amplified by the small charge and complex shape of electride wavefunctions. For these reasons, popular integration methods like the Bader method usually fail to assign any charge to the bare electrons in an electride. To address this challenge, we develop an algorithm that instead partitions the charge based on the electron localization function (ELF), a popular scheme for visualizing chemically important features in molecules and solids. The algorithm uses Bader segmentation of the ELF to find the electride electrons and Voronoi segmentation of the ELF to identify atoms. We apply this method, “BadELF”, to the quantification of atomic radii and oxidation states in both ionic compounds and electrides. For ionic compounds, we find that the BadELF method yields radii that agree closely with Shannon crystal radii, while the oxidation states agree closely with the Bader method. When applied to electrides, however, only the BadELF algorithm yields chemically meaningful charges. We argue that the BadELF method provides a useful strategy to identify electrides and obtain new insight about their most essential property: the quantity of electrons within them.
Ultrastable halide perovskite CsPbBr3 photoanodes achieved with electrocatalytic glassy-carbon and boron-doped diamond sheets
Authors: Zhu Zhonghui , Daboczi Matyas , Xuan Yimin , Liu Xianglei , Eslava Salvador
Published: October 2023

Halide perovskites exhibit exceptional optoelectronic properties for photoelectrochemical production of solar fuels and chemicals but instability in aqueous electrolytes, which hampers their application. Here we present ultrastable perovskite CsPbBr3-based photoanodes achieved with both multifunctional glassy carbon and boron-doped diamond sheets coated with Ni nanopyramids and NiFeOOH. These perovskite photoanodes achieve record operational stability in aqueous electrolytes, preserving 95% of its initial photocurrent density for 168 h of continuous operation with the glassy carbon sheets and 97% for 210 h with the boron-doped diamond sheets, due to the excellent mechanical and chemical stability of glassy carbon, boron-doped diamond, and nickel metal. Moreover, these photoanodes reach a low water-oxidation onset potential close to +0.4 VRHE and photocurrent densities close to 8 mA cm-2 at 1.23 VRHE, owing to the conductivity of glassy carbon and boron-doped diamond and the catalytic activity of NiFeOOH. The applied catalytic, protective sheets employ earth abundant elements and straightforward fabrication methods, engineering a solution for the success of halide perovskites in stable photoelectrochemical cells.
A fast, convenient, polarizable electrostatic model for molecular dynamics
Authors: Wang Liangyue , Schauperl Michael , Mobley David L. , Bayly Christopher , Gilson Michael K.
Published: October 2023

We present an efficient polarizable electrostatic model, utilizing typed, atom-centered, polarizabilities and the fast direct approximation, designed for efficient use in molecular dynamics (MD) simulations. The model provides two convenient approaches to assigning partial charges in the context of the atomic polarizabilities. One is a generalization of RESP, called RESP-dPol, and the other, AM1-BCC-dPol, is an adaptation of the widely used AM1-BCC method. Both are designed to accurately replicate gas-phase QM electrostatic potentials. Benchmarks of this polarizable electrostatic model against gas-phase dipole moments, molecular polarizabilities, bulk liquid densities, and static dielectric constants of organic liquids, show good agreement with the reference values. Of note, the model yields markedly more accurate dielectric constants of organic liquids, relative to a matched non-polarizable force field. MD simulations with this method, which is currently parameterized for molecules containing elements C, N, O, and H, run about only 3.6-fold slower than fixed charge force fields, while simulations with the self-consistent mutual polarization average 4.5-fold slower. Our results suggest that RESP-dPol and AM1-BCC-dPol afford improved accuracy, relative to fixed charge force fields, and are good starting points for developing general, affordable, and transferable polarizable force fields.
High conversion of methane to methyl ester at 298 K
Authors: Xu Lai , Mei Chong , Zhao Mengdi , Lu Wenjun
Published: October 2023

To establish an aerobic oxidation of methane to produce methanol in high yield under ambient conditions is one of dreams to researchers in both academia and industry. However, although many progresses have been made on methane functionalization for several decades, it is still a grand challenge to break through the selectivity-conversion limit in the aerobic oxidation of methane to methanol or methyl ester especially at room temperature. Herein we report a simple visible-light driven reaction of CH4/O2 with CF3CO2H (TFA) to CH3-O-COCF3 (MTFA) at 298 K, just using catalytic NaNO2 in aqueous HCl/TFA solution. In a batch reaction of CH4/O2 (1:5, 0.4 MPa), the yield of MTFA is over 90%. In a 7-day continuous experiment of CH4/O2 (2:1, 0.1 MPa), both the MTFA selectivity and the methane conversion are over 90% based on the input methane. The turnover frequency (TOF) is 2.5 mol_MTFA mol_(NaNO_2 )-1 h-1, and the turnover number (TON) is over 400. A reasonable reaction mechanism is suggested and partial confirmed by experiments, involving NOCl as a crucial species in the two-phase aerobic oxidation of methane to methyl ester. Methanol could be obtained by a common hydrolysis of MTFA at 298 K. Neither metal catalysts nor special reagents are necessary in this two-step conversion of methane to methanol.
Detection, quantification, and isomer differentiation of per- and polyfluoroalkyl substances (PFAS) using MALDI-TOF with trapped ion mobility
Authors: Reynolds Aidan , Smith Abby , Qiu Tian (Autumn)
Published: October 2023

Per- and polyfluoroalkyl substances (PFAS) are a class of organic compounds that have attracted global attention for their persistence in the environment, exposure to biological organisms, and their adverse health effects. There is an urgent need to develop analytical methodologies for characterization of PFAS in various sample matrices. Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) represents a chromatography-free MS method that performs laser-based ionization and in situ analysis on samples. In the present study, we present PFAS analysis by MALDI-time-of-flight MS with trapped ion mobility (TIMS), which provides an additional dimension of gas phase separation based on the size-to-charge ratios. MALDI matrix composition and key instrument parameters were optimized to produce different ranges of calibration curves. Parts per billion range of calibration curves were achieved for a list of legacy and alternative perfluorosulfonic acids (PFSAs) and perfluorocarboxylic acids (PFCAs), while ion mobility spectrum filtering enabled parts per trillion (ppt) range of calibration curves for PFSAs. We also successfully demonstrated the separation of three perfluorooctanesulfonic acid (PFOS) structural isomers in the gas phase using TIMS. Our results demonstrated the new development of utilizing MALDI-TOF-MS coupled with TIMS for fast, quantitative, and sensitive analysis of PFAS, paving ways to future high-throughput and in situ analysis of PFAS such as MS imaging applications.
Electronic Structure of Metalloporphenes, Antiaromatic Analogs of Graphene
Authors: Pavlak Ivan , Matasović Lujo , Buchanan Eric , Michl Josef , Rončević Igor
Published: October 2023

Zinc porphene is a two-dimensional material made of fully fused zinc porphyrins in a tetragonal lattice. It has a fully conju-gated π-system, making it similar to graphene. Zinc porphene has recently been synthesized and shown to be a semiconduc-tor (Nat. Comm., 2023, 14, 6308.). This is in contrast with all previous predictions of its electronic structure, which indi-cated metallic conductivity. We show that the gap-opening in zinc porphene is caused by a Peierls distortion of its unit cell from square to rectangular, thus giving the first account of its electronic structure in agreement with experiment. Accounting for this distortion requires a proper treatment of electron delocalization, which can be done using hybrid functionals with a substantial amount of exact exchange. Such a functional, PBE38, is then applied to predict the properties of many first tran-sition row metalloporphenes, some of which have already been prepared. We find that changing the metal strongly affects the electronic structure of metalloporphenes, resulting in a rich variety of both metallic conductors and semiconductors, which may be of great of interest to molecular electronics and spintronics. Properties of these materials are mostly governed by the extent of the Peierls distortion and the number of electrons in their π system, analogous to changes in aromaticity observed in cyclic conjugated molecules upon oxidation or reduction. These results give an account of how the concept of antiaromaticity can be extended to periodic systems.
Understanding the Role of Electrode Thickness on Redox Flow Cell Performance
Authors: Muñoz-Perales Vanesa , van der Heijden Maxime , de Haas Victor , Olinga Jacky , Vera Marcos , Forner-Cuenca Antoni
Published: October 2023

The electrode thickness is a critical design parameter to engineer high-performing flow cells by impacting the available surface area for reactions, current and potential distributions, and required pumping power. To date, redox flow cell assemblies employ repurposed off-the-shelf fibrous electrodes which feature a broad range of thicknesses. However, comprehensive guidelines to select the optimal electrode thickness for a given reactor architecture remain elusive. Here, we investigate the effect of the electrode thickness in the range of 200 - 1100 µm on the cell performance by stacking electrode layers in four different flow cell configurations – Freudenberg paper and ELAT cloth electrodes combined with flow-through and interdigitated flow fields. We employ a suite of polarization, electrochemical impedance spectroscopy and pressure drop measurements together with pore network modeling simulations to correlate the electrode thickness for various reactor designs to the electrochemical and hydraulic performance. We find that thicker electrodes (420 µm paper electrodes and 812 µm cloth electrodes) are beneficial in combination with flow-through flow fields, whereas when using interdigitated flow fields, thinner electrodes (210 µm paper electrodes and 406 µm cloth electrodes) result in a better current density and pressure drop trade-off. We hope our findings will aid researchers and technology practitioners in designing their electrochemical flow cells under convective operation.
Role of cationic organisation on water dynamics in saponite clays
Authors: Marry Virginie , Le Crom Sébastien , Ferrage Eric , Michot Laurent , Farago Bela , Delville Alfred , DUBOIS Emmanuelle
Published: October 2023

Water dynamics impacts many phenomena from geosciences to biology, especiallly in confined environments. In the presence of charged interfaces, there are some ions the role of which with regards to the water dynamics is unclear. Here a synthetic saponite clay, which is oriented in a film, is used as confining medium in the bilayer state. It confines two water layers between negatively charged planes, the charge of which is compensated by sodium cations. Water dynamics is determined both parallel and perpendicular to the charged clay layers with Neutron Spin Echo (NSE). This technique gives access to long enough times and directly provides the intermediate scattering function that is calculated on the other hand by Molecular Dynamics (MD) simulations. These latter also enable the study of cations dynamics, not experimentally accessible on this time scale. The results point towards a huge role of these cations on the water dynamics, mainly through their local structure and localization between the charged confining planes.
High Aspect Ratio Silver Nanogrids by Bottom-Up Electrochemical Growth as Transparent Electrode
Authors: Bleiji Yorick , Cordaro Andrea , Tabernig Stefan , Alarcón-Lladó Esther
Published: October 2023

A scalable selective area electrochemical method is reported for the fabrication of interconnected metal nanostructures. In this work, the fabrication of silver nanowire grids for the application of transparent electrodes is explored. The presented method is based on a through-the-mask electrodeposition method, where the mask is made using substrate conformal imprint lithography. We find that the nucleation density of the silver nanoparticles is the key parameter for the successful homogenous void-free filling of the template. We independently control the density of the silver nuclei and their growth by using a double potential pulse. The silver nanowire grids show high transmission (95.9%) and low sheet resistance (as low as 3.7 Ohm/sq), resulting into a superior Figure of Merit (FoM). Due to the bottom-up nature of this technique, arbitrarily high aspect ratio nanowires can be achieved and therefore the relationship of decreasing transmission with decreasing sheet resistance is broken. The presented method can be generalized to the large-area nanofabrication of any well-defined nanostructure design of any metal transparent electrode for multiple applications.
Photoresponsive Arylazopyrazole Surfactant/PDADMAC Mixtures: Reversible Control of Bulk and Interfacial Properties
Authors: Hardt Michael , Honnigfort Christian , Carrascosa-Tejedor Javier , Braun Marius , Winnall Samuel , Glikman Dana , Gutfreund Philipp , Campbell Richard A. , Braunschweig Bjoern
Published: October 2023

In many applications of polyelectrolyte/surfactant (P/S) mixtures, it is difficult to fine-tune them after mixing the components without changing the sample composition, e.g. pH or the ionic strength. Here we report on a new approach where we use photoswitchable surfactants to enable drastic changes in both the bulk and interfacial properties. Poly(diallyldimethylammonium chloride) (PDADMAC) mixtures with three alkyl-arylazopyrazole butyl sulfonates (CnAAP) with -H, -butyl and -octyl tails are applied and E/Z photoisomerization of the surfactants is used to cause substantially different hydrophobic interactions between the surfactants and PDADMAC. This affects significantly the P/S binding and allows for tuning both the bulk and interfacial properties of PDADMAC/CnAAP mixtures through light irradiation. For that, we have fixed the surfactant concentrations at values where they exhibit pronounced surface tension changes upon E/Z photoisomerization with 365 nm UV light (Z) and 520 nm green (E) light and have varied the PDADMAC concentration. The electrophoretic mobility can be largely tuned by photoisomerisation of CnAAP surfactants and P/S aggregates, which can even exhibit a charge reversal from negative to positive values or vice versa. In addition, low colloidal stability at equimolar concentrations of PDADMAC with CnAAP surfactants in the E configuration lead to the formation of large aggregates in the bulk which can be redissolved by irradiation with UV light when the surfactant‘s alkyl chain is short enough (C0AAP). Vibrational sum-frequency generation (SFG) reveals changes at the interface similar to the bulk, where the charging state at air-water interfaces can be modified with light irradiation. Using SFG spectroscopy, we interrogated the O-H stretching modes of interfacial H2O and provide qualitative information on surface charging that is complemented by neutron reflectometry, from which we resolved the surface excess of PDADMAC and CnAAP at the air-water interface, independently.
Visible light photocatalytic water remediation strategies using a novel black TiO2 based material optimized for in-flow applications
Authors: Scaiano Juan , Yaghmaei Mahzad , da Silva Daliane R.C. , Rutajoga Nelson , Currie Sara , Li Yiran , Vallieres Morgan , Joshi Neeraj , Wang Bowen
Published: October 2023

Contaminated drinking water is a major health hazard in large urban areas as well as remote communities. Several pollutants detected in untreated wastewater are hormonal disruptors which are harmful to consumers as well as aquatic life. In this contribution, we present a novel material designed for visible light driven decontamination of water. This material is based on a glass fiber support loaded with black TiO2, a modified form of TiO2 with an expanded light absorption capacity without any toxic metal or non-metal dopants. The photocatalyst developed in our laboratories is ideal for flow as the active material remians fixed while there is continous passage of solution occuring under visible light irradiation. The effectiveness of the catalyst is demonstrated with crocin and 17β-estradiol, the former being a natural carotenoid used as a screening tool, and the latter being a common hormonal disruptor. Our work shows that under visible light illumination, our supported black TiO2 is able to degrade these water contaminants with greater efficiency than conventional TiO2. Using this framework we envision that our findings can contribute to the production of inexpensive, large-scale solar or LED-based water decontamination systems which would be rapidly deployable to sites in need. Operation of such systems would require minimal training and could be monitored remotely. In addition to the catalyst’s non-toxicity and in-flow compatibility, the material also has a long shelf life and is easy and inexpensive to produce, making it an attractive candidate for developing water treatment devices