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Development of a flexible digital twin framework for accelerators using design patterns
Full text linkModern accelerator design increasingly relies on prototyping and validating commissioning software through digital twins. Digital twins serve as natural test benches for validating and monitoring the required physics software stack. These twins must align with the current design state of the accelerator from the project s inception to the machine s commissioning. The authors have developed a modern digital twin framework based on software design patterns. Its architecture emphasizes clean design principles with minimal coupling between components. Its setup requires only lattice and device configuration data. Thanks to its design, it seamlessly integrates into prototyping environments or control system infrastructures. In this paper, we briefly describe the design patterns underlying this architecture, highlight the flexibility and advantages of the infrastructure, and outline the steps needed to implement it for a machine currently lacking a digital twi
Ti3C2Tx MXene Thin Films and Intercalated Species Characterized by IR to UV Broadband Ellipsometry
Full text linkMXenes are two dimensional 2D materials with versatile applications in optoelectronics, batteries, and catalysis. To unlock their full potential, it is crucial to characterize MXene interfaces and intercalated species in more detail than is currently possible with conventional optical spectroscopies. Here, we combine ultra broadband ellipsometry and transmission spectroscopy from the mid infrared IR to the deep ultraviolet UV to probe quantitatively the composition, structure, transport, and optical properties of spray coated Ti3C3Tx MXene thin films with varying material properties. We find film thickness heterogeneity and surface roughness in the low nanometer range as well as depth dependent conductivity properties, which we quantify with a graded Drude model. The optically determined sheet resistance is confirmed by four point probe measurements. Furthermore, we employ density functional theory calculations to assign the observed absorption bands in the MXene dielectric function to various interband transitions from mixed MXene surface terminations. The prominent 1.48 eV 833 nm spectral feature is found to be related to oxygen termination. Additional plasmonic effects are also suggested. Finally, we leverage the chemical sensitivity of state of the art IR ellipsometry to separate the fingerprints of intercalated species within the MXene from the dominant Drude contributions, presenting for the first time a set of infrared optical constants of intercalated water. This work lays the foundation for optical metrology for interface engineering of MXene and other 2D material
Filling the gaps Introducing plasticizers into pi conjugated OPE NH2 Langmuir layers for defect free anisotropic interfaces and membranes towards unidirectional mass, charge, or energy transfer
No full textThe construction of ultrathin membranes from linearly aligned it electron systems is advantageous for targeted energy, charge, or mass transfer. The Langmuir Blodgett LB technique enables the creation of such membranes, especially with amphiphilic it electron systems. However, these systems often aggregate, forming rigid Langmuir monolayers with defects or holes. In this study we introduce plasticizers to effectively address this issue. To create anisotropic membranes, we used an oligo phenylene ethynylene derivative OPE NH2 as an linear amphiphile and bisphenol A di tert butyl ester BPAE as a plasticizer. We analyzed surface pressure mean molecular area N mma isotherms and characterized Langmuir monolayers with Brewster Angle Microscopy BAM , to determine the optimal miscibility of OPE NH2 with BPAE. Detailed analysis of hole areas filled was performed through image binarization. We identified an optimal BPAE concentration of 4 mol in the OPE NH2 Langmuir monolayer. Our BAM image evaluation via binarization determined the difference between the mean molecular areas of close packed Langmuir domains and those quantified via the N mma isotherm. This study presents an automated method for BAM image analysis and a new approach for fabricating defect free anisotropic molecular monolayers of it conjugated amphiphile
X ray absorption spectroscopy of FeH to aid its identification in astrochemical environments
Full text linkWe present the first absorption spectrum of the unperturbed diatomic molecular ion FeH in any wavelength range. The cryogenic X ray absorption spectrum at the L2 and L3 edge is consistent with an iron 3d occupation of 6.24e. Comparison with the interstellar absorption spectrum of Cygnus X 1 indicates that FeH cannot be ruled out as a component of the absorbing mediu
A Stage Gate Framework for Upscaling of Single Junction Perovskite Photovoltaics
Full text linkTo address the challenge of upscaling single junction perovskite photovoltaics PV toward market relevant performance in a structured and efficient manner, a stage gate approach that divides the process into stages according to technology readiness levels TRLs is proposed. Whereas the first stage contains only material research, the later stages are concerned with the development from lab scale devices to large area modules, and properties such as device size as well as processing methods are adapted step by step toward commercializable techniques. The stages are connected by gates that specify the criteria that must be met for a material or process to be transferred to the next stage. In addition, a literature survey for the keywords perovskite and module is performed. This analysis shows that most of the reported modules have an area between 10 cm2 and 20 cm2, corresponding to stage 3 or TRL 5 in the scheme, and operational stability is often incompletely reported. These findings analysis indicate a significant gap in the research focus on large area modules and elevated stress and field tests, which are essential for transitioning to commercial applications. It is suggested to use the proposed stage gate process as an efficient and structured guideline toward commercializing perovskite P
R for Reactive Revealing Rhodium, Ruthenium, and Rhenium s Rare Oxides through X ray Absorption Spectroscopy
No full textDiscovering compounds that present transition metals with high oxidation states or reactive oxygen species, such as the oxygen centered radical, is of great scientific interest, as they have key applications as oxidizing agents, catalysts, or reaction intermediates. Due to the high reactivity of such chemical entities, experimental investigations of their electronic structures are limited. The study of small systems as models can be used to understand their properties and expand the applicability of related materials. This work aims to investigate highly oxidized transition metals, bringing a new perspective towards their electronic structure and properties. For that, X ray absorption spectroscopy, at the oxygen K and metal M3 or N3 edges of [MOn] molecular ions M transition metal, n integer , is used to identify the spectroscopic signatures of oxygen ligands and assign the oxidation state of the metal. The highly oxidized [MOn] gas phase species are produced by argon sputtering of a metal target in the presence of oxygen. The X ray absorption spectroscopy, performed in ion yield mode, is used here as a tool to directly probe the electronic ground state structure of the investigated samples, that are analysed in stable conditions in their lowest energy states. The highest oxidation state of rhodium is here presented for the first time in the trioxidorhodium VII cation, for which the rhodium M3 edge shows the chemical shift corresponding to its high oxidation state, while the oxygen K edge shows the spectral signature of oxo ligands. Further, the oxygen centered radical tetroxidoruthenium VIII cation and diradical tetroxidorhenium VII cation are here investigated by X ray absorption spectroscopy for the first time, where the oxygen centered singly occupied molecular orbitals are identified by a low energy transition at the oxygen K edge, which is suppressed upon hydrogenation. Computational studies corroborate the experimental observations, that will hopefully contribute to the scientific knowledge of these species and their oxidative propertie
Synthesis of Poly Itaconate s With High Monomer Conversion Applying Emulsion Polymerization
Full text linkItaconic acid and its derivatives can be obtained from renewable feedstocks. However, there are only very limited applications of polymers containing itaconic acid so far. One limitation of the application of this polymer is that commonly utilized polymerization techniques lead to very low conversions of the corresponding monomers. Consequently, itaconic acid and its derivatives are generally considered difficult or poorly polymerizable monomers. The current study presents the improvement of the polymerization by applying an emulsion polymerization of itaconic acid esters, leading to very high monomer conversions with a residual monomer content of less than
A Copper Binding Peptide with Therapeutic Potential against Alzheimer?s Disease From the Blood Brain Barrier to Metal Competition
No full textAlzheimer s disease AD is the most common form of dementia worldwide. AD brains are characterized by the accumulation of amyloid beta peptides A beta that bind Cu2 and have been associated with several neurotoxic mechanisms. Although the use of copper chelators to prevent the formation of Cu2 A beta complexes has been proposed as a therapeutic strategy, recent studies show that copper is an important neuromodulator that is essential for a neuroprotective mechanism mediated by Cu2 binding to the cellular prion protein PrPC . Therefore, in addition to metal selectivity and blood brain barrier BBB permeability, an emerging challenge for copper chelators is to prevent the formation of neurotoxic Cu2 A beta species without perturbing the neuroprotective Cu2 PrPC interaction. Previously, we reported the design of a tetrapeptide TP that withdraws Cu2 from A beta 1 16 and impacts the Cu2 induced aggregation of A beta 1 40 . In this study, we improved the drug like properties of TP in a BBB model, evaluated the metal selectivity of the optimized peptide TP , and tested its effect on Cu2 coordination to PrPC and proteins involved in copper trafficking, such as copper transporter 1 and albumin. Our results show that changing the stereochemistry of the first residue prevents TP degradation in the BBB model and coadministration of TP with a peptide that increases BBB permeability allows its passage through the BBB model. TP is highly selective toward Cu2 in the presence of Zn2 ions, transfers Cu2 to copper trafficking proteins, and forms a ternary TP Cu2 PrP species that does not perturb the physiological conformation of PrP and displays only a minor impact in the neuroprotective Cu2 dependent interaction of PrPC with the N methyl d aspartate receptor. Overall, these results show that TP displays desirable features for a copper chelator with therapeutic potential against AD. Moreover, this is the first study that explores the effect of a Cu2 chelator with therapeutic potential for AD on Cu2 coordination to PrPC an emerging key player in AD pathology , integrating recent knowledge about metalloproteins involved in AD with the design of copper chelators against A
Synthesis of Iron IV Alkynylide Complexes and Their Reactivity to Form 1,3 Diynes
No full textThe isolation of thermally unstable and highly reactive organoiron IV complexes is a challenge for synthetic chemists. In particular, the number of examples where the C based ligand is not part of the chelating ligand remains scarce. These compounds are of interest because they could pave the way to designing catalytic cycles of bond forming reactions proceeding via organoiron IV intermediates. Herein, we report the synthesis and characterization, including single crystal X ray diffraction, of a family of alkynylferrates III and Fe IV alkynylide complexes. The alkynylferrates III are formed by transmetalation of the Fe III precursor [ N3N FeIII] N3N 3 amp; 8722; is tris N tert butyldimethylsilyl 2 amidoethyl amine with lithium alkynylides, and their further one electron oxidation enables the synthesis of the corresponding Fe IV alkynylides. The electronic structure of this family of organometallic Fe III and Fe IV complexes has been thoroughly investigated by spectroscopic methods EPR, NMR, 57Fe Mössbauer, X Ray absorption XAS and emission XES spectroscopies and theoretical calculations. While alkynylferrates III are sluggish to engage into C amp; 8722;C bond forming processes, the Fe IV alkynylides react to afford 1,3 diynes at room temperature. A bimolecular reductive elimination from a bimetallic Fe IV intermediate to form the 1,3 diynes is proposed based on the mechanistic investigations performe
Spin Crossover in a Dinuclear Iron II Complex on Highly Oriented Pyrolytic Graphite An X Ray Absorption Spectroscopy Study
Full text linkThe spin crossover SCO properties of the dinuclear complex [ Fe H2B pz 2 2 2 mu ac bipy 2 ] mathematical equation are studied as sub monolayer and thin film deposited by an ultrahigh vacuum liquid jet deposition technique on highly oriented pyrolytic graphite HOPG by X ray absorption spectroscopy. A comparison of the SCO properties of thin films and a dropcast sample indicates that the spin switching probability of the thin films is limited due to substrate molecule interactions. The maximum percentage of molecules in the low spin LS state observed for 0.7 and 1.8 monolayers ML is amp; 8776;43 at a temperature of 80 amp; 8201;K in comparison to the dropcast sample where amp; 8776;66 of the complex is in the LS state. The similar switching properties of the dropcast sample as of a bulk powder sample confirm that the SCO properties are not affected by the presence of solvent necessary for deposition. The soft X ray induced excited spin state trapping SOXIESST effect is pronounced in all samples, although the light induced high spin HS fraction of the dropcast and the thin film samples on HOPG is higher as compared to the HS fraction attained by SOXIESST, which confirms the sensitivity of the complex to ligh