ChimiaPub Date : 2025-04-30DOI: 10.2533/chimia.2025.200
Paul Dutheil, Martin Heule, Patrick Steinegger
{"title":"Development of Flow Electrolytic Strategies for Separation and Radiometric Analysis of Radionuclides.","authors":"Paul Dutheil, Martin Heule, Patrick Steinegger","doi":"10.2533/chimia.2025.200","DOIUrl":"https://doi.org/10.2533/chimia.2025.200","url":null,"abstract":"<p><p>Radionuclides are used and produced for a variety of applications, such as in the framework of energy production and nuclear medicine. This requires appropriate monitoring which in turn translates into the analysis of a variety of radionuclides in demanding sample matrices. Radionuclide analysis is a challenging task and often requires complex chemical processing of the samples prior to radiometric measurements. This requirement arises due to interfering radionuclides as well as matrix elements, which typically prevent a direct measurement by α- and γ-spectrometry, liquid scintillation counting or mass spectrometry. Despite offering promising possibilities, electrochemical approaches have been rarely used so far for the separation and analysis of radionuclides. Here, we present the development of fast flow-through electrolytic separation approaches for the analysis of carrier-added/-free radionuclides in fundamental and applied research.</p>","PeriodicalId":9957,"journal":{"name":"Chimia","volume":"79 4","pages":"200-203"},"PeriodicalIF":1.1,"publicationDate":"2025-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143982212","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ChimiaPub Date : 2025-04-30DOI: 10.2533/chimia.2025.249
Willi M Amberg, Erick M Carreira
{"title":"Base Metal Meets Photoredox Chemistry - Advances in Fully Catalytic Metal-Catalyzed Hydrogen Atom Transfer Reactions.","authors":"Willi M Amberg, Erick M Carreira","doi":"10.2533/chimia.2025.249","DOIUrl":"https://doi.org/10.2533/chimia.2025.249","url":null,"abstract":"<p><p>Metal-catalyzed hydrogen atom transfer (MHAT) has become a valuable approach for the functionalization of alkenes and toward complex molecular structures. This review discusses recent advancements in the field, particularly the integration of metal catalysis with photoredox catalysis which obviates the need for sacrificial reagents. Key transformations, including heterocycle formation, olefin hydrofunctionalization, and semi-pinacol rearrangements are examined in detail, highlighting the potential of photo-MHAT for efficient and sustainable synthetic strategies.</p>","PeriodicalId":9957,"journal":{"name":"Chimia","volume":"79 4","pages":"249-254"},"PeriodicalIF":1.1,"publicationDate":"2025-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143966922","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ChimiaPub Date : 2025-04-30DOI: 10.2533/chimia.2025.220
Andrea Levy, Andrej Antalík, Jógvan Magnus Haugaard Olsen, Ursula Rothlisberger
{"title":"Multiscale Molecular Dynamics Simulations with the MiMiC Framework.","authors":"Andrea Levy, Andrej Antalík, Jógvan Magnus Haugaard Olsen, Ursula Rothlisberger","doi":"10.2533/chimia.2025.220","DOIUrl":"https://doi.org/10.2533/chimia.2025.220","url":null,"abstract":"<p><p>Multiscale simulations are essential techniques in computational chemistry, providing insights into complex phenomena across extended temporal and spatial scales. With a particular interest in the dynamics of such processes, we developed MiMiC, a framework for efficient multiscale molecular dynamics simulations suited for high-performance computing. One of its key characteristics is a flexible design where external specialized programs handle individual subsystems. This article reviews the core features and some recent advancements in MiMiC, particularly the integration of OpenMM and CP2K.</p>","PeriodicalId":9957,"journal":{"name":"Chimia","volume":"79 4","pages":"220-223"},"PeriodicalIF":1.1,"publicationDate":"2025-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143966663","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ChimiaPub Date : 2025-04-30DOI: 10.2533/chimia.2025.245
Dorothea Kossmann
{"title":"Studying Intracellular pH of Bacteria with Fluorescent Tools.","authors":"Dorothea Kossmann","doi":"10.2533/chimia.2025.245","DOIUrl":"10.2533/chimia.2025.245","url":null,"abstract":"<p><p>This perspective discusses the relevance of studying the intracellular pH of pathogenic bacteria. Acidic environments trigger phenotype switches, increasing stress tolerance and antibiotic persistence - key challenges in treating bacterial infections. Understanding these phenotypic adaptations under clinically relevant stress conditions is important for elucidating bacterial survival mechanisms. Here, we discuss fluorescent tools to monitor pH homeostasis in bacterial cells and how advances in this field could shed light on pathogen resilience to antibiotics and human immune responses.</p>","PeriodicalId":9957,"journal":{"name":"Chimia","volume":"79 4","pages":"245-248"},"PeriodicalIF":1.1,"publicationDate":"2025-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143961477","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ChimiaPub Date : 2025-04-30DOI: 10.2533/chimia.2025.232
Flavio Augusto Von Philipsborn, Christian Adlhart
{"title":"Towards Biocompatible Cellulose Nanofiber Sponges with Tailored Pore Geometries.","authors":"Flavio Augusto Von Philipsborn, Christian Adlhart","doi":"10.2533/chimia.2025.232","DOIUrl":"https://doi.org/10.2533/chimia.2025.232","url":null,"abstract":"<p><p>Cellulose nanofiber (CNF) sponges or CNF aerogels are promising biocompatible materials with applications ranging from biomedicine to environmental remediation. The highly porous architecture of these sponges - which is crucial for their functionality - is significantly influenced by the freezing step during fabrication. This review explores the critical role of freezing techniques in tailoring pore geometry and, consequently, the macroscopic properties of CNF sponges. We discuss conventional directional freezing methods and their limitations, highlighting the advantages of dynamic freezing for achieving isotropic pore structures. Furthermore, we examine various crosslinking strategies to enhance the stability and mechanical properties of CNF sponges. Finally, we present recent findings from our laboratory demonstrating the successful fabrication of biocompatible and crosslinked CNF sponges with tailored pore geometries using a dynamic freezing approach.</p>","PeriodicalId":9957,"journal":{"name":"Chimia","volume":"79 4","pages":"232-236"},"PeriodicalIF":1.1,"publicationDate":"2025-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143974736","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ChimiaPub Date : 2025-04-30DOI: 10.2533/chimia.2025.208
Kazutaka Sakamoto, Christophe Copéret
{"title":"Investigation of Pt-based Model Catalysts for Propane Dehydrogenation Reaction.","authors":"Kazutaka Sakamoto, Christophe Copéret","doi":"10.2533/chimia.2025.208","DOIUrl":"https://doi.org/10.2533/chimia.2025.208","url":null,"abstract":"<p><p>Large scale exploitation of shale gas has stimulated the developments of on-purpose propane dehydrogenation (PDH) technologies. Pt-based PDH catalysts have been utilized in industry, e.g. Pt-Sn/Al2O3 and Pt-Ga/ Al2O3, where the actual role of metal dopants is not fully understood. In this regard, the development of model systems possessing tailored surface sites is necessary in order to look into the structure-activity relationships. In that context, the surface organometallic chemistry (SOMC) approach has emerged as a powerful tool to yield PDH model catalysts, revealing that the formation of alloyed particles and residual unreduced metal sites are important for high productivity and stability.</p>","PeriodicalId":9957,"journal":{"name":"Chimia","volume":"79 4","pages":"208-211"},"PeriodicalIF":1.1,"publicationDate":"2025-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143978851","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ChimiaPub Date : 2025-04-30DOI: 10.2533/chimia.2025.216
Meghna A Manae, Jeremy O Richardson
{"title":"Quantum Tunnelling in Triplet Carbenes Explained by Instanton Theory.","authors":"Meghna A Manae, Jeremy O Richardson","doi":"10.2533/chimia.2025.216","DOIUrl":"https://doi.org/10.2533/chimia.2025.216","url":null,"abstract":"<p><p>The temperature-dependent reactivity of three triplet carbenes (denoted as C1, C2 and C3) were investigated using instanton theory. Experiments showed that C1undergoes an intramolecular reaction at very low temperatures, while C2 requires heating, and C3 remains stable despite heating. The reactions studied involved both hydrogen transfer and intersystem crossing, and therefore we considered sequential and concerted processes as possible candidates for the reaction mechanism. Calculations of instanton tunnelling pathways in conjunction with double-hybrid density functional theory showed that the sequential mechanism dominates the reaction at high temperatures while the concerted mechanism is the predominant channel at low temperatures. The observed temperature-dependent reactivity can thus be explained in terms of a crossover temperature where the mechanism switches. This study suggests a powerful way to control the reactivity of triplet carbenes solely by tuning temperature.</p>","PeriodicalId":9957,"journal":{"name":"Chimia","volume":"79 4","pages":"216-219"},"PeriodicalIF":1.1,"publicationDate":"2025-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143976204","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ChimiaPub Date : 2025-04-30DOI: 10.2533/chimia.2025.212
Kevin Kleemann, Michael Sander
{"title":"Accounting for Molecular Weight Distribution Dynamics in the Environmental Fate Assessment of Water-Soluble Polymers.","authors":"Kevin Kleemann, Michael Sander","doi":"10.2533/chimia.2025.212","DOIUrl":"https://doi.org/10.2533/chimia.2025.212","url":null,"abstract":"<p><p>Water-soluble polymers (WSPs) are widely used in industrial and agricultural applications, as well as in consumer products. After use, they may be released into both engineered and natural environments, where their fate is governed by transfer and transformation processes which are strongly influenced by their molecular weight distribution (MWD). Unlike traditional low molecular weight organic chemicals, WSPs are ensembles of molecules with varying chain lengths. This work suggests the use of Monte Carlo (MC) simulations to model shifts in MWDs resulting from abiotic and biotic chain scission reactions in receiving environments. We specify key factors influencing chain-scission selectivity, including chain-end scissions, molecular weight-dependent scissions, and site-specific scissions. Experimental validation of MC simulation predictions presents analytical challenges, requiring high-resolution MWD characterization of WSPs and reliable extraction techniques from complex environmental matrices. MC simulations may play a pivotal role not only in identifying the most relevant molecular weight (MW) ranges for targeted analysis but also in predicting and elucidating environmental chain scission processes.</p>","PeriodicalId":9957,"journal":{"name":"Chimia","volume":"79 4","pages":"212-215"},"PeriodicalIF":1.1,"publicationDate":"2025-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143978369","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ChimiaPub Date : 2025-04-30DOI: 10.2533/chimia.2025.228
Carlotta Seno
{"title":"Metal Oxides of Group 4: General Insights and the Synthesis of ZrO<sub>2</sub>/HfO<sub>2</sub> and ZrO<sub>2</sub>:Eu/ZrO<sub>2</sub> Core/Shell Nanocrystals.","authors":"Carlotta Seno","doi":"10.2533/chimia.2025.228","DOIUrl":"https://doi.org/10.2533/chimia.2025.228","url":null,"abstract":"<p><p>Metal oxide nanocrystals, like ZrO2 and HfO2, serve as hosts for optically active lanthanide ions. However, synthesizing colloidally stable nanocrystals with complex architectures remains challenging. We have pioneered the synthesis of metal oxide core/shell nanocrystals, where HfO2 epitaxially grows onto ZrO2. The beneficial effect of the shell on the optical properties is demonstrated by investigating the photoluminescence of ZrO2:Eu and of ZrO2:Eu/ZrO2 after growing a protective zirconia shell on it.[1].</p>","PeriodicalId":9957,"journal":{"name":"Chimia","volume":"79 4","pages":"228-231"},"PeriodicalIF":1.1,"publicationDate":"2025-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143979145","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ChimiaPub Date : 2025-04-30DOI: 10.2533/chimia.2025.204
Colin Hansen, Dirk Baabe, Marc D Walter, Christophe Copéret
{"title":"Surface Organo-Iron Chemistry Towards Efficient Reverse Water-Gas Shift Catalysis.","authors":"Colin Hansen, Dirk Baabe, Marc D Walter, Christophe Copéret","doi":"10.2533/chimia.2025.204","DOIUrl":"https://doi.org/10.2533/chimia.2025.204","url":null,"abstract":"<p><p>The low-temperature reverse water-gas shift (LT-RWGS) is a critical and energy effective technology for syngas production and the mitigation of anthropogenic carbon emissions. Developing efficient and well-defined catalysts for the LT-RWGS, from which structure-activity relationships can be drawn, is a significant challenge. Herein we describe how the identification of the grafting properties of tetramesityldiiron (Fe2Mes4) helps with designing tailored and highly efficient catalysts of PtFe@SiO2 composition. To that end, a molecular analogue, Fe2Mes3OSi(OtBu)3, was synthesized and characterized by X-ray diffraction, 57Fe-Mössbauer and 1H-NMR spectroscopy. The results confirmed that tetramesityldiiron grafts onto silica via selective displacement of a single mesityl ligand, forming Fe2Mes3@SiO2, while steric hindrance likely prevents secondary interactions with surface siloxide bridges. This work highlights the potential of tetramesityldiiron as a versatile precursor for synthesizing bimetallic MFe@SiO2 systems, enabling the rational development of highly efficient LT-RWGS and CO2 hydrogenation catalysts.</p>","PeriodicalId":9957,"journal":{"name":"Chimia","volume":"79 4","pages":"204-207"},"PeriodicalIF":1.1,"publicationDate":"2025-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143982214","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}