Transition Elements Research Articles

Probing soft X-ray induced photoreduction of a model Mn-complex at cryogenic conditions

Soft X-ray absorption spectroscopy of first row transition elements at their respective L-edges provides important information about the oxidation and spin states of the metal centers. However, the associated sample damage in radiation-sensitive samples substantially alters the electronic and chemical structures of redox-active metal centers. Here, we measure the soft X-ray spectrum of the model MnIII(acac)3 complex containing a redox-active MnIII metal center in an octahedral environment with a superconducting transition-edge sensor detector. To reduce the secondary damage resulting primarily from the diffusion of radicals and electrons, the spectra are collected at 30 K and 80 K on solid samples. Starting from the first scan, we detect the contribution of X-ray induced sample damage leading to a change in the MnII intensity. However, at low temperatures, particularly at 30 K, we do not observe a gradual increase in the radiation damage with successive scans with the X-ray beam at the same spot. At our estimated dose of 90 kGy, we find 62% of MnIII(acac)3 is still intact at 30 K. However, at room temperature, we see a gradual increase in radiation damage with increasing numbers of scans at the same spot, which is consistent with the possibility of increased diffusion rates of secondary radicals and electrons as noted in other studies.

Estimation of Hardness of Single-Phase Metallic Alloys

First, we discuss a common feature of single-phase pure metals and amorphous and high-entropy alloys: the maximum value of hardness corresponding to a valence electron count (VEC) value of around 6.5–7. This correlation is explained by the coincidence that by subtracting the number of sp valence electrons (Nsp = 2) from the VEC we obtain the maximal number of unpaired d electrons, Nd = 4.5–5 in the 3d, 4d, and 5d rows of transition elements. These unpaired d electrons form orbital overlap bonding, which is stronger than the isotropic metallic bonds of a delocalized electron cloud. The more unpaired d electrons there are, the higher the bonding strength. Second, we will discuss the hardness formulas derived from cohesion energy and shear modulus. We will demonstrate that both types of formulas originate in the electrostatic energy density of metallic bonds, expressing a 1/R4 dependence. Finally, we show that only two parameters are sufficient to estimate hardness: the atomic radius and the cohesion-based valence. In the case of alloys, our formula gives a lower bound on the hardness only. It is not suitable for calculation of the hardness increase caused by solid solution, grain size, precipitation, and phase mixture.

Data-Driven Accelerated Discovery Coupled with Precise Synthesis of Single-Atom Catalysts for Robust and Efficient Water Purification.

The development of advanced catalysts frequently employs trial-and-error methods and is lack of highly controlled synthesis, resulting in unsatisfactory development efficiency and performance. Here we propose a data-driven prediction coupled with precise synthesis strategy to accelerate the development of single-atom catalysts (SACs) for efficient water purification. The data-driven approach enables the rapid screening and prediction of high-performance SACs from 43 metals-N4 structures comprising transition and main group metal elements, followed by validation and structural modulation for improved performance through a highly controllable hard-template method. Impressively, a well-designed Fe-SAC with a high loading of Fe-pyridine-N4 sites (~3.83 wt%) and highly mesoporous structure, exhibits ultra-high decontamination performance, representing the best Fenton-like activities for sulfonamide antibiotics to date. Furthermore, the optimized Fe-SAC shows excellent robust environmental resistance and cyclic stability with almost 100% degradation efficiency of sulfonamide antibiotics for 100-h continuous operation. Theoreticalcalculations reveal that Fe-pyridine-N4 sites can reduce the energy barrier of intermediate O* formation, the rate-determining step, resulting in highly selective generation of singlet oxygen. The integration of data-driven method with precise synthesis strategy provides a novel paradigm for the rapid development of high-performance catalysts for environmental field as well as other important fields including sustainable energy and catalysis.

Effect of Trace Sc Addition on Microstructure and Mechanical Properties of Al-Zn-Mg-Cu-Zr Alloy

Transition element microalloying is important for improving the properties of Al-Zn-Mg-Cu alloys. Nevertheless, along with its high costs, increasing Sc content generates a harmful phase, limiting the strength of the alloy. In this experiment, we reduced the amount of Sc added to a Zr-containing Al-Zn-Mg-Cu alloy by one order of magnitude. The microstructure and mechanical properties of the alloys were studied by means of tensile tests, field emission scanning electron microscopy (FESEM), and transmission electron microscopy (TEM). The findings indicate that the alloys’ mechanical properties were progressively enhanced with the increase in Sc content from 0 to 0.04%. After adding 0.04% Sc, the tensile strength and yield strength of the Al-Zn-Mg-Cu-Zr-Sc alloy increased by 20.9% and 24.3%, reaching 716 MPa and 640 MPa, respectively, and the elongation decreased, but still reached 12.93%. The strengthening mechanisms of the trace addition of Sc are fine grain strengthening and precipitate and disperse strengthening, and Al3(Sc, Zr) particles hinder the dislocation and grain boundary movement. Drawing on insights from other studies on Sc microalloying in Al-Zn-Mg-Cu alloys, this experiment successfully reduced the amount of Sc added by an order of magnitude, the alloys properties were improved, and the effect of strengthening remained good.

Review article the significance applications Schiff rules: Systematic review of the literature

The number of Shaf rules is one of the most important bridge bonds used in coordination chemistry. It has been used in the preparation of a large number of transition elements in particular and in the preparation of complexes with metal ions in general due to its coordination strength and also its ability to form complexes with different bases and different uses., and they are organic compounds containing the azomethine group (C=N-R R2). For the first time in the year (1864), I was the first to discover the process of condensing aliphatic ,aromatic ketones or aldehydes with primary aromatic amines or aliphatic, where the carbonyl group and primary amines are condensed so that the monoalkyl amine or monoaryl amine is added to the atom carbon of the carbonyl group belonging to the middle aldehyde or ketone. Later, the absence of the water molecule of the intermediate compound (N-substituted imine) which represents the base of the final shef result And why are there so many names, including amines, as well as when it is derived from a ketone, it is called ketamine, and when it is derived from an aldehyde, it is called an aldehyde. This biological activity of Scheff's rules also plays important roles in environmental chemistry, analytical chemistry, and industrial chemistry and is considered as a catalyst in photochemical reactions

Redox Status-Selective Imaging of Iron in Vegetative and Pathogenic Fungal Cells Using Fluorescent Dyes Synthesized Via Simple Chemical Reactions.

Iron plays a prominent role in various biological processes and is an essential element in almost all organisms, including plant-pathogenic fungi. As a transition element, iron occurs in two redox states, Fe2+ and Fe3+, the transition between which generates distinct reactive oxygen species (ROS) such as H2O2, OH- anions, and toxic OH· radicals. Thus, the redox status of Fe determines ROS formation in pathogen attack and plant defense and governs the outcome of pathogenic interactions. Therefore, spatially resolved visualization of Fe2+ and Fe3+ are essential to understand microbial pathogenesis. Here, we report a simple method for synthesis of the redox-state-selective dyes pyrene-tetramethyl piperidinyl oxyl (p-TEMPO) and 4-(4-methylpiperazine-1)-7-nitrobenz-2-oxa-1,3-diazole (MPNBD) for fluorescence microscopy-based imaging of Fe2+ and Fe3+ ions. Using these dyes, the occurrence and spatial distribution of Fe2+ and Fe3+ ions in vegetative and pathogenic hyphae of the hemibiotrophic maize anthracnose fungus Colletotrichum graminicola are shown. [Formula: see text] Copyright © 2025 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.

As(III) Removal via Combined Addition of Mg- and Ca-Based Adsorbents and Comparison to As(V) Removal via Those Mechanisms

Damage to human health caused by As-contaminated water can be prevented using proper As-removal techniques, such as employing excellent arsenic adsorbents. In this study, the combined addition of Mg- and Ca-based adsorbents was investigated for the efficient removal of As from contaminated water. Following a previous study on As(V), As-removal tests targeting As(III) and several additional tests, including X-ray diffraction analysis, were conducted to clarify the mechanism of the improved performance of the combined-addition As removal. Similarly as for As(V), the combined additions of both MgCO3 + CaO and MgCO3 + Ca(OH)2 improved As(III)-removal performance while inhibiting the leaching of base material components; however, they did not remove As(III) as effectively as As(V). The differences in the removal ratios of As(V) and As(III) in these combined additions were concluded to be primarily due to the different As-removal mechanisms. Mg(OH)2 and CaCO3 were generated, and As(III) was incorporated into the generated precipitate of Mg(OH)2 but not into that of CaCO3. Conversely, As(V) was incorporated into both Mg(OH)2 and CaCO3. Additionally, MgCO3 + Ca(OH)2 was evaluated as a more efficient combined-addition method because MgCO3 + Ca(OH)2 exhibited a higher As-removal ratio value than MgO + CaO. Proposals have been made to remove As(III) using activated carbon modified with heavy metals or transition elements, or concrete waste grafted with polymers, but these methods are complicated to prepare, costly, and involve the risk of leaching of harmful components. Adsorbents that use general Mg and Ca components as their base material do not contain such harmful components. The Mg- and Ca-based adsorbents are readily available and low-cost, and, best of all, there is no concern that they will leach harmful components. Therefore, widespread use of Mg- and Ca-based adsorbents as a measure against arsenic contamination could greatly contribute to a sustainable society.

Best Practices for Transition Design of Concrete Pavement Intersections and Related Transitions

Pavement transitions are one of the key elements of pavement performance often overlooked in the design process. Improperly designed pavement transition elements lead to poor pavement performance and often creating a need for frequent maintenance and repair. Transition elements are necessary to ensure a smooth transition between two different pavement sections and to minimize future pavement performance issues. This paper addressed the transition of intersections, ramp/gore areas, drainage inlets, and the conversion between a portland cement concrete and asphalt concrete materials. The design standards of most state Department of Transportation (DOT) were reviewed and the best practices identified toward incorporating them into a set of guidelines for design and construction purposes. Moreover, field visits were conducted to survey the conditions of these transition types relative to slab cracking and associated distresses due to inappropriate jointing or other design-related factors. Based on this information, specific design practices are suggested to enhance the design standard for different transition types based on simple and sound concepts substantiated by observed field performance. The guidelines address the design of concrete pavement transition areas including joints and related details.

Synthesis, structure, oxygen evolution reaction (OER) and visible-light assisted organic reaction studies on A2M2TeB2O10 (A = Ba and Pb; M = Mg, Zn, Co, Ni, Cu, and Fe).

Compounds with the general formula A2M2TeB2O10 (A = Ba and Pb; M = Mg, Zn, Co, Ni, Cu, and Fe) have been synthesised via solid-state techniques and characterised. The structure exhibits M2B2O10 layers connected by TeO6 octahedra giving rise to a three-dimensional structure with voids, where Ba2+ ions reside. Substitution of Mg by transition elements (M = Co, Ni, and Cu) in Ba2Mg2TeB2O10 and (Ba0.5Pb1.5)Mg2TeB2O10 gives rise to interesting colored compounds. NIR reflectivity studies indicated that white-colored compounds exhibited good NIR reflectivity, which was is comparable to that of TiO2. Dielectric studies indicated reasonable values with low dielectric loss at low frequencies. The cobalt-substituted compounds Ba2(MgCo)TeB2O10 and (Ba0.5Pb1.5)(MgCo)TeB2O10 were explored towards the oxygen evolution reaction (OER) in an alkaline medium. The compound (Ba0.5Pb1.5)(MgCo)TeB2O10 was found to be a good electrocatalyst for the OER with a faradaic efficiency of ∼96%. The Cu-substituted compound Ba2(Mg1.5Cu0.5)TeB2O10 was found to be a good photocatalyst for the formation of α-chloroketones under visible light in the presence of molecular oxygen.

CCQM-K155: elements and tributyltin in seawater

Main textTwenty National Metrology Institutes and Designated Institutes registered in the CCQM Key Comparison of CCQM-K155 "Elements and Tributyltin in Seawater" and nineteen institutes submitted their results. Participants were requested to evaluate the mass fractions, expressed in ng/g, of arsenic, cadmium, copper, lead, nickel, zinc and ng/kg level of tributyltin in seawater. Key Comparison Reference Values (KCRVs) are assigned to the various measurands by the NIST decision tree approach (NDT). Participants used analytical methods of their choice. Most participants employed dilution or co-precipitation for sample treatment and analyzed the samples using Isotope Dilution Mass Spectrometry (IDMS) or standard addition method with ICP-MS, applying various interference removing techniques for different elements. For tributyltin, most participants utilized derivatization followed by liquid-liquid extraction, with analysis conducted using isotope dilution GC-ICP-MS.Successful participation in CCQM-K155 demonstrates measurement capabilities for determining mass fraction of transition elements (excluding mercury) and metalloids/semi-metals, with mass fractions ranging from 0.1 ng/g to 50 ng/g. Additionally, it covers small organo-tin and organo-mercury compounds with mass fractions from 1 ng/kg to 50 ng/g in a high-salt content matrix (seawater).To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database https://www.bipm.org/kcdb/.The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

Эколого-геохимическая оценка накопления и миграции тяжелых металлов в почве разновозрастных виноградников интенсивного типа в условиях эродированного ландшафта Южнобережной зоны Крыма

The article presents data on the accumulation of copper, zinc, lead, manganese and chromium in brown typical light clay soil and migration along the slope in two intensive vineyards aged 38 and 6 years, grown in the conditions of the eroded landscape of the Southern coast of Crimea. The research results showed that the gross copper content in the soil of a vineyard aged 38 years ranged from 113 to 140 mg/ kg exceeding the approximate permissible concentration of this element by 1.5 – 6.1%, in the soil of a vineyard aged 6 years – from 68 to 88 mg/ kg without exceeding the established regulatory values. On average, the content of mobile forms of copper in the soil of a 38-year-old vineyard turned out to be 2.5 times higher than that of a 6-year-old vineyard, and for both ampelocenoses exceeded the maximum permissible concentration by 1.2 – 4.1 times. Of all the metals studied, only copper had a clark concentration in the soil of 2.5 – 5.2 due to its significant agrogenic contribution with copper-containing fungicides, whereas for zinc, lead, manganese and chromium, the clark concentration was either close to the lithospheric level, or the elements were dispersed. Sublateral migration of both gross copper and, in particular, its mobile forms with accumulation of average strength (the coefficient of lateral differentiation was 1.08 – 1.49) in the transeluvial and transaccumulative parts of the slope has been established in the soil of the transitional elements of the slope of the age vineyard. Keywords: COPPER, BROWN TYPICAL SOIL, PESTICIDES, AMPELOCENOSIS, ACCUMULATION, SPATIAL HETEROGENEITY, SLOPE, SOUTHERN COAST OF CRIMEA

SYNTHESIS, CHARACTERIZATION AND INVITRO-ANTIMICROBIAL ACTIVITIES OF Ni (II) AND Fe (II) COMPLEXES OF SOME HYDRAZONE LIGANDS

hydrazone which are compounds that have N-N bond in addition to –C=N- bond of well-known Schiff’s bases. They are formed by the reaction of carbonyl compounds (ketones or aldehydes) with hydrazides or its derivatives. They form coordination compounds with almost all transition elements, forming various geometries. The present work focuses on the synthesis and characterization of Ni (II) and Fe (II) complexes of some hydrazone ligands. For this purpose, three (3) different hydrazone ligands were synthesized, by reacting different types of hydrazide derivatives with carbonyl compounds (ketones or aldehydes). Each of these ligands were used to formed complexes with Ni (II) and Fe (II), using their hexahydrated metal salts. The complexes were characterized using; IR spectroscopy, UV-Visible spectroscopy, elemental analysis, conductivity measurement and magnetic susceptibility measurement.

Navigating from industry to higher education: Practitioner transitions to academic life

AbstractIn this paper, we entwine sympathetic concepts of liminality and workplace identity to capture processual, agential and emotional elements of transition for established professionals from other sectors taking up academic careers in a digitised UK business school. We undertake interpretative analysis of explicit and latent responses through three core themes exploring processes of transition, agencies of transition and emotions of transition through anonymised interviews conducted with 15 participants coming in from a variety of industrial and service roles. With a rationale of better understanding barriers and ambiguities experienced during times of transition, the paper considers perceptions of ambiguity and flux experienced by those undertaking second careers in the context of marketised higher education, arguing that coming in from a profession is complex and unsettling. The paper argues for greater institutional focus on improving perceptions of belonging, valorisation and recognition for those negotiating the ritual and contested space of transition, particularly in light of increasing collaboration between academia and practice and growing student numbers in this space. It concludes that in the light of continued policy decisions embracing rapid growth in apprenticeship and other practice‐based degree programmes, university managers need active strategies to retain and develop those from industry and other professional backgrounds.

Peculiarities of transformations in systems of coordination nitrate precursors of rare earth elements and lithium during the formation of polyfunctional oxide materials

The article summarizes information important for practical use on the conditions of formation, composition, structure, forms of Ln coordination polyhedra, type of ligand coordination, and characteristic properties of lithium coordination nitrates of rare earth elements of the cerium subgroup of the isostructural series Li3[Ln2(NO3)9]∙3H2O (Ln – La–Nd) (predecessors of promising modern multifunctional materials). The obtained data (as primary information) can serve as the basis for identifying, monitoring the phase state of processing objects in the preparatory stages; selection of criteria for the compatibility of components in the formation of single-layer and layered nanostructured oxide systems of lanthanides and transition elements with the structure of defective perovskite, garnet in the form of powders, thick films, bulk ceramics; development of various combined methods of their activation and establishment of technologically functional dependencies; controlled modification of the properties of the target product; optimization of synthesis modes of lithium-conducting systems such as electrodes of rechargeable batteries, electrolyte membranes and sensors, elements and instrument structures of modern telecommunications systems.

ARCHITECTURAL AND STRUCTURAL CHARACTERISTICS OF MİMAR SİNAN MOSQUES: A CLASSIFICATION STUDY

With the conquest of Istanbul, the Ottoman Empire synthesized the building culture of Islam and the Seljuks with Byzantine architecture and built magnificent structures. The domed central space is an important element of Turkish mosque architecture, and many original attempts were made in this direction. In the 16th century, when Ottoman architecture reached its most glorious age, the idea of creating a clear space was put into practice in the Ottoman period by removing the closed courts shaped around the central dome used in Seljuk architecture in terms of plan construction. The centralist fiction developed with Mimar Sinan and reached its highest point with the Selimiye Mosque. The subject of this study is the domed mosques built by Mimar Sinan. Within the scope of the research, first, a list of mosques designed and built by Mimar Sinan was prepared, and a literature review was conducted. These buildings were evaluated typologically in terms of their construction dates, plan types, last congregation features, number of minarets and minaret balconies, and construction materials. These buildings' structural features and transition elements to the dome were also classified. In this way, it is aimed to associate the mosques designed and built by Mimar Sinan typologically.

Chemical and Vibrational Criteria for Identifying Early Sèvres Factory Porcelain Productions

Thirteen porcelains assigned to Sèvres factory productions and a few references to the other contemporary factories (Chantilly, Limoges, and Venice) have been studied on-site with a portable X-ray fluorescence (pXRF) spectrometer in order to control the provenance attribution. Characteristic XRF signals of major elements (Si, Ca, K, Pb) and minor/trace (Au, Bi, As, Ti, Co, Cu, Zn, Ni, Y, Zr, Rb, and Sr) elements are compared for the paste, blue mark, various glazed (colored) areas, and gilding. The comparison of peak intensities clearly distinguishes different types of hard- and soft-paste porcelain, made from either similar or distinct raw materials. The analysis of transition elements associated with cobalt identifies three types of cobalt blue and reveals that du Barry-style decoration on certain artifacts was typical of 19th-century production. On-site comprehensive studies of the two famous Etruscan-style breast bowls from Rambouillet Castle dairy, using pXRF and Raman spectroscopy, confirm the use of soft-paste porcelain for the cup and hard-paste for its support, providing detailed information on the use of gold nanoparticles in the burgundy-colored decoration.

Accelerating Tandem Electroreduction of Nitrate to Ammonia via Multi-Site Synergy in Mesoporous Carbon-Supported High-Entropy Intermetallics.

The electrochemical nitrate reduction reaction (NO3 -RR) for ammonia (NH3) synthesis represents a significant technological advancement, yet it involves a cascade of elementary reactions alongside various intermediates. Thus, the development of multi-site catalysts for enhancing NO3 -RR and understanding the associated reaction mechanisms for NH3 synthesis is vital. Herein, a versatile approach is presented to construct platinum based high-entropy intermetallic (HEI) library for NH3 synthesis. The HEI nanoparticles (NPs) are uniformly supported on a 2D nitrogen doped mesoporous carbon (N-mC) framework, featured with adjustable compositions (up to eight elements) and a high degree of atomic order (over 90%). Guided by the density functional theory (DFT) calculations and atomic structural analysis, a quinary Pt0.8Fe0.2Co0.2Ni0.2Cu0.2 HEI NPs based N-mC catalyst is designed, which demonstrates a large ammonia Faradaic efffciency (>97%) and a remarkable recyclability (>20 cycles) under both acidic and basic conditions. The combined in situ experimental analysis and further DFT calculation suggests that the well-defined multi-sites nature of the HEI NPs cooperate for a tandem reduction mechanism, in which the Pt-X (X represents the other four transition elements) bridging sites offer optimal adsorption for key nitrogen-oxygen species while the Pt sites facilitate the generation and adsorption of *H species.

Efficacy of nickel doped graphitic carbon nitride as energy storage material

Abstract The current article reports the synthesis of graphitic carbon nitride (GCN), through simple thermal decomposition of urea at a moderate temperature of 550 °C and doping of as-developed material with transition element like nickel. The proper phase formation of the sample was confirmed by x-ray diffraction whereas electron microscopic images analyzed the sample morphologies. The successful doping was verified by x-ray photoelectron spectroscopy whereas thermogravimetric study predicted the stability of the material under elevated temperature. Fourier transformed infrared spectroscopy showed that after Ni doping there is a substantial change in the vibrational energy level of the sample. UV–vis reflectance spectra confirmed the reduction of optical bandgap after metal doping. The samples show promises towards supercapacitor application. Cyclic voltametric study shows that after metal doping the value of specific capacitance became 162 Fg−1 at scan rate 5 mV s−1 and when the same was calculated from galvanostatic charging–discharging characteristics the values came even higher. The energy and power density of both the samples was calculated and all these when compared with different reported results, confirmed the performance of Ni doped GCN is comparable and sometimes even far better along with the advantages of the easy, large scale and high yield synthesis approach.

Achieving energy resilience: The joint role of environmental policy stringency and environmental awareness

This paper examines the critical interplay between environmental policy stringency, public environmental awareness, and energy resilience, leveraging a dataset for 32 OECD countries between 2004 and 2020. Further, it explores the channels through which these variables influence energy resilience. Principal component analysis (pca) is adopted to derive the multi-dimensional index of energy resilience based on three pillars, renewable energy, energy access, and energy efficiency. The findings underscore a significant positive relationship between stringent environmental policies, environmental awareness, and energy resilience. Additionally, environmental awareness and environmental policy stringency are shown to exert a positive effect on renewable energy and enhance energy access. Environmental policy stringency is found to have a significant negative impact on energy intensity, i.e. a positive impact on energy efficiency. The results demonstrate that by increasing public environmental awareness and implementing more stringent environmental policies policymakers can improve energy resilience, energy efficiency, and the share of renewable energy. The latter are considered essential elements for the environmental transition emerging as a prominent solution when addressing climate change challenges.

A novel approach for large-scale hybrid mesh generation on distributed systems

This study presents an approach for the generation of a large-scale viscous mesh using a parallel advancing layer method based on distributed systems with multi-cores. A triangular surface mesh that conforms with the original geometrical model is prepared as input and decomposed into multiple subdomains. A coarser background mesh with high-quality viscous elements from the same model is employed for parallel computation. Instead of using a conventional approach to generate layer-wise prismatic elements, a normal calculation through linear interpolation is implemented to overcome the boundary problems arising in distributed systems. A novel strategy to deal with cross-processor transition elements is proposed to reduce frequent communications during viscous mesh generation. To improve the parallel efficiency, a fast domain decomposition method is introduced to speed up the parallel meshing procedure of tetrahedral elements. Numerical experiments are performed on high-performance computing systems with billions of mesh elements to demonstrate the effectiveness and efficiency of the proposed approach and numerical simulation results represent a promising applicability.