Chimia最新文献

A digital ion trap (DIT) mass spectrometer was developed to extend the mass range in comparison to conventional ion traps. This was achieved by changing the RF voltage from a sinusoidal to a rectangular waveform. In addition to the extended mass range, the size of the instrument was miniaturized. To show the benefits of this development, MALDI applications in MS1, MS2, and MS3 are presented: On one hand, it is possible to analyze intact proteins, on the other hand the instrument enables insights into the structure of antibodies and glycoproteins after enzymatic digestion and collision-induced dissociation (CID).

Mössbauer spectroscopy is an effective technique used to examine the iron atom electronic environments in both biomolecular molecules and whole animal studies. Because of its sensitivity to nuclear hyperfine interactions, this technique yields incredibly accurate data regarding the electronic and magnetic states of nuclei, chemical bonds, and the local electronic environment structure around iron atoms. This review demonstrates how Mössbauer spectroscopy contributes to biomedical sciences. The use of Mössbauer spectroscopy in the fields of general biology is discussed, as well as studies that included bacterial analyses, studies related to protein materials, and pharmaceutical studies. In addition, although beyond the scope of this review, the use of Mössbauer spectroscopy to study model compounds to aid in understanding the iron proteins is briefly referred to.

At the extremes, all analytical spectrometric measurements are limited by the resolution of the spectrometer system. Spectral overlaps, isobars in the case of mass spectrometry, can lead to the implementation of complex and time-consuming chemical separations to alleviate those interferences. In the area of elemental/isotopic mass spectrometry, use of sector-field instruments can provide a mass resolution of ~10,000, but still necessitate chemical separations. Described here is the coupling of the liquid sampling-atmospheric pressure glow discharge (LS-APGD) microplasma to ultra-high resolution Orbitrap mass analyzer systems to yield mass resolution values ranging from 70k to 1M. Resolution of this order, with commensurate improvements in precision and accuracy, holds the promise to affect elemental/isotopic determinations without the need for chemical separations.

Demand for lithium is expected to quadruple by the end of the decade. Without new sources of production, the supply-demand curve is expected to invert. Traditional geological reserves will not be able to meet the anticipated gap, thus unconventional sources of lithium will need to be utilized, setting the stage for fierce competition for perhaps the most critical of mineral resources required for the energy transition. Direct Lithium Extraction refers to the umbrella of technologies being developed to access lithium from unconventional sources. Electrochemical extraction offers significant promise for its selectivity and low operating cost when coupled with renewable energy. This review aims to describe materials and process design considerations for electrochemical extraction of lithium from aqueous sources with a specific emphasis on ζ-V2O5 designed in our research group as an insertion host. We point to specific strategies for improving capacity and selectivity for electrochemical lithium extraction based on materials design across length scales. Strategies range from site-selective modification of insertion hosts to controlled tortuosity of ion diffusion pathways in porous electrode architectures. Electrochemical lithium extraction from unconventional sources stands poised to be a linchpin of a sustainable economy when coupled with cleaning of wastewater, hydrogen generation, and recovery of ancillary critical metals.

The stereoregularity of a polymer plays a key role in determining its properties. While stereocontrol can easily be achieved in coordination and ionic polymerization, it remains a challenge with radical polymerization. Considering the ubiquity and versatility of radical polymerization, significant efforts have been made over the past 50 years to address this issue. In this mini review, we highlight some of the strategies that have been developed to enable stereospecific radical polymerization, from the use of Lewis acid additives to the application of high electric fields. We hope that this review will provide the reader with a comprehensive overview of the current state of the art and equip them with the foundational knowledge needed to explore new avenues in this domain.

In this perspective, we will discuss the impact of some of the most recent advancements in materials discovery, particularly focusing on the role of robotics, artificial intelligence, and self-driving laboratories, as well as their implications for the Swiss research landscape. While it seems timely to aim for broad, revolutionary breakthroughs in this field, we argue that more incremental steps - such as, for example, fully automatic grinding of solid powders or fully automated Rietveld refinements - may have a more significant impact on materials discovery, at least in the short run. In the center of these considerations is how small, interdisciplinary groups can drive significant progress by contributing targeted innovations, such as e.g.robotic sample preparation or computational predictions. Additionally, given the large investments that are necessary for future infrastructures in materials discovery, we discuss the potential case for the establishment - in the long run - of a national infrastructure, a Swiss Materials Discovery Lab, to support automated material synthesis and advanced characterization, ultimately accelerating innovation in both academic and industrial settings.

Ten years after the discovery of colloidal lead halide perovskite nanocrystals (LHP NCs), the field has witnessed substantial progress in synthetic methods, understanding of their surface chemistry and unique optical properties, precise control over NC size, shape, and composition. Ligand engineering, particularly with cationic and zwitterionic head groups, massively enhanced NC stability, compatibility with organic solvents, and photoluminescence efficiency. These breakthroughs allowed for the self-assembly of monodisperse NCs into complex long-range ordered superlattices and enabled the exploration of collective optical phenomena, such as superfluorescence. The development of low-cost scalable approaches like microfluidic systems and mechanochemical synthesis paved the way for the commercialization of LHP NCs, particularly for the down-conversion films in blue-backlit LCDs and as thermally-efficient color converters in pixelated displays. This review aims to trace the journey of these advancements, focusing on contributions from Switzerland, and outline future directions in this rapidly evolving field, such as quantum light sources, photocatalysis, etc.

Photon interconversion promises to alleviate thermalization losses for high energy photons and facilitates utilization of sub-bandgap photons - effectively enabling the optimal use of the entire solar spectrum. However, for solid-state device applications, the impact of intermolecular interactions on the energetic landscape underlying singlet fission and triplet-triplet annihilation upconversion cannot be neglected. In the following, the implications of molecular arrangement, intermolecular coupling strength and molecular orientation on the respective processes of solid-state singlet fission and triplet-triplet annihilation are discussed.