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This paper provides an overview of the new features of the finite element library deal.II, version 9.6. [ABSTRACT FROM AUTHOR]

Since widespread vaccination against COVID-19, the development of effective antiviral drugs, and the decreasing number of patients with COVID-19 in intensive care, the risk from SARS-CoV-2 infection appears less threatening. However, studies show that a significant number of patients suffer from long-term sequelae, even months after SARS-CoV-2 infection. The so-called post-COVID syndrome (PCS) often presents a diagnostic and treatment challenge for physicians. This study protocol describes the "All Eyes on PCS" study, which aims to investigate the retinal microvasculature in PCS patients and COVID-19-recovered patients to provide new insights into the pathophysiology of PCS. "All Eyes on PCS" is a prospective, case–control study with the primary objective of detecting endothelial dysfunction (ED) in patients with PCS. Therefore, we intend to recruit patients with PCS, fully SARS-CoV-2-infection-recovered (CR) participants, and SARS-CoV-2-infection-naïve (CN) participants. Baseline measurements will include: (1) patient-specific characteristics, (2) biochemistry, (3) retinal vessel analysis (RVA), (4) survey questionnaires as patient-reported outcomes measurements (PROMs), (5) optical coherence tomography (OCT), OCT angiography (OCTA), and adaptive optics (AO), (6) blood pressure recordings, (7) handgrip strength test. After 6 months, baseline measurements will be repeated in the PCS cohort, and after 1 year, a telephone query will be conducted to assess residual symptoms and treatment needs. The aim of this study is to gain insight into the pathophysiology of PCS and to provide an objective biomarker for diagnosis and treatment, while also creating a comprehensive clinical database of PCS patients. ClinicalTrials.gov Identifier: NCT05635552; Date: 2.12.2022. [ABSTRACT FROM AUTHOR]

Taking inspiration from the recent rise in interest on calcined clays, the RILEM technical committee RILEM TC 282-CCL on Calcined Clays as Supplementary Cementitious Materials has been summarising knowledge on a wide variety of topics related to the use of calcined clays in cement and concrete. In this article, the working group 2 of this committee summarises recent global efforts on the industrialisation of calcined clay cements, to bring the work of the committee into context. Clays have been a key construction material since Roman times but are now designated as crucial for enhancing cement industry sustainability in the short to mid-term. Several industrial and semi-industrial trials that have recently produced calcined clays through various techniques, such as static, rotary, and suspension calcination technologies are covered in this paper, while worldwide cement production trials with calcined clays and limestone are also discussed. Major projects considering local clays as construction materials are presented as examples of global interest in the subject. Due to interest in achieving climate goals, calcined clays are being rapidly reintroduced into the cement industry, and academic research has played an important role in this process. The examples discussed in this article demonstrate the importance of greater and swifter knowledge transfer from academia to industry. The work also demonstrates the need to upgrade industrial equipment and design new efficient equipment to eliminate the use of fossil fuels for clay calcination, a process that requires relatively lower temperature than clinker production. The challenges in achieving net-zero carbon emissions in clay calcination technologies are also discussed. Overall, this paper presents the context in which the RILEM TC 282-CCL operated. [ABSTRACT FROM AUTHOR]

The paper focuses on first-order invariant-domain preserving approximations of hyperbolic systems. We propose a new way to estimate the artificial viscosity that has to be added to make explicit, conservative, consistent numerical methods invariant-domain preserving and entropy inequality compliant. Instead of computing an upper bound on the maximum wave speed in Riemann problems, we estimate a minimum wave speed in the said Riemann problems such that the approximation satisfies predefined invariant-domain properties and predefined entropy inequalities. This technique eliminates non-essential fast waves from the construction of the artificial viscosity, while preserving pre-assigned invariant-domain properties and entropy inequalities. [ABSTRACT FROM AUTHOR]

This paper describes a class of shape optimization problems for optical metamaterials comprised of periodic microscale inclusions composed of a dielectric, low-dimensional material suspended in a nonmagnetic bulk dielectric. The shape optimization approach is based on a homogenization theory for time-harmonic Maxwell's equations that describes effective material parameters for the propagation of electromagnetic waves through the metamaterial. The control parameter of the optimization is a deformation field representing the deviation of the microscale geometry from a reference configuration of the cell problem. This allows for describing the homogenized effective permittivity tensor as a function of the deformation field. We show that the underlying deformed cell problem is well-posed and regular. This, in turn, proves that the shape optimization problem is well-posed. In addition, a numerical scheme is formulated that utilizes an adjoint formulation with either gradient descent or BFGS as optimization algorithms. The developed algorithm is tested numerically on a number of prototypical shape optimization problems with a prescribed effective permittivity tensor as the target. [ABSTRACT FROM AUTHOR]

The incorporation of BN units in organic scaffolds by isoelectronic/isosteric substitution of selected CC couples has emerged as an efficient tool to produce new materials with useful properties and functions. The knowledge about BN‐doped inorganic–organic hybrid polymers, however, is still rather scarce. This is especially true for linear or cyclolinear macromolecules that feature longer inorganic chains. Herein, we introduce 1,2,5‐azadiborolane as a polymer building block for the first time. An attempt to apply it for the synthesis of a cyclolinear poly(iminoborane) resulted after only two B−N coupling events in the formation of a molecular compound comprising a chain of three nitrogen and two boron atoms – as confirmed by single‐crystal X‐ray diffractometry. In combination with a p‐phenylene diamine‐based co‐monomer, we accomplished to incorporate the 1,2,5‐azadiborolane into a hybrid polymer of considerable molecular weight that features a B2N3 chain. We additionally synthesized a small molecular model compound for the polymer and characterized it crystallographically as well. Comparison of the UV‐vis spectra of the monomer, the oligomer, and the polymer revealed systematic red‐shifts of the longest‐wavelength absorption band with increasing number of BN units in the chain. [ABSTRACT FROM AUTHOR]

Despite the great success of the concept of doping organic compounds with BN units to access new materials with tailored properties, its use in polymer chemistry has only been realized quite recently. Herein, we present a comprehensive study of oligo‐ and poly(arylene iminoborane)s comprising a backbone of phenylene or thiophene moieties, as well as combinations thereof, linked via B=N units. The novel polymers can be regarded as BN analogues of poly(p‐phenylene vinylene) (PPV) or poly(thiophene vinylene) (PTV) or their copolymers. Our modular synthetic approach allowed us to prepare four polymers and 12 monodisperse oligomers with modulated electronic properties. Alternating electron‐releasing diaminoarylene and electron‐accepting diborylarylene building blocks gave rise to a pronounced donor‐acceptor character. Effective π‐conjugation over the arylene iminoborane backbone is evidenced by systematic bathochromic shifts of the low‐energy UV‐vis absorption maximum with increasing chain length, which is furthermore supported by crystallographic and computational investigations. Furthermore, all compounds investigated show emission of visible light in the solid state and aggregation‐induced emission (AIE) behavior, due to the presence of partially flexible linear B=N linkages in the backbone. [ABSTRACT FROM AUTHOR]

SCMs with a large specific surface area, such as calcined clays or fine limestone powder, can significantly accelerate the occurrence of the aluminate heat flow peak during the early hydration of blended cements. These systems therefore require a higher amount of sulfate. While this effect has been drawn back to the sulfate incorporation into C‐S‐H, which is formed more rapidly due to the filler effect, it has been recently shown that in systems with high amounts of metakaolin, the sulfate balance is influenced by further mechanisms. This study provides new results on the influence of aluminum‐rich and aluminum‐free SCMs on the early hydration of alite in presence of calcium sulfate. A synthesized alite was blended with 5 wt% of anhydrite and its hydration was investigated by isothermal calorimetry and in‐situ XRD at a w/b ratio of 0.5. It was shown that the formed C‐S‐H is able to take up the calcium and sulfate ions, indicated by a depletion of the solid anhydrite after approximately 20 hours. This process is significantly accelerated by incorporating 30 wt% of a fine limestone filler. The addition of metakaolin leads to an acceleration of the alite hydration compared to the reference as well, but to a significantly lower extend compared to the limestone. However, this system requires a lower degree of alite reaction to reach sulfate depletion. This indicates that in metakaolin‐rich systems, the sulfate demand is influenced by further effects. The results from in‐situ‐XRD reveal that significant ettringite formation is taking place in the metakaolin‐blended system already during the first hours of hydration. Correlations between the degree of alite hydration and the rate of sulfate depletion provide new insights into the mechanisms affecting the sulfate balance and early hydration of blended cements. [ABSTRACT FROM AUTHOR]

Calcined clays are the most promising future supplementary cementitious material which are capable of replacing fly ashes and blast furnace slag on the long run due to their potential to achieve high cement replacement levels and their global availability. In the last decade most research has focused on calcined clays rich in the 1:1 kaolinite. Clay with less than 20 to 25 % kaolinite were seen as worthless. Even the content of 2:1 phyllosilicates in the kaolinitic clays was neglected and not even mentioned although especially these clays are dominant in areas like central and northern Europe. Here, highly kaolinitic clays are rare or used by other industries leading to high prices. This paper is based on published works and highlights whether information obtained for calcined 1:1 dominated clays can be applied for calcined 2:1 dominated clays or not and where further research is needed. [ABSTRACT FROM AUTHOR]

An unprecedented poly(thiophene iminoborane)—a boron–nitrogen analogue of the well‐established conjugated organic polymer poly(thiophene vinylene)—is presented. The polymer synthesis is achieved by selective Si/B exchange polycondensation of a 2,5‐diborylthiophene with a 2,5‐diaminothiophene derivative. For the latter, a facile synthetic strategy is devised, which makes this versatile, strongly electron‐releasing building block easily accessible. The novel polymer and a series of monodisperse thiophene iminoborane oligomers reveal systematic bathochromic shifts in their absorption with increasing chain length, and thus extended π‐conjugation over the BN units along the backbone, which is further supported by TD‐DFT calculations. [ABSTRACT FROM AUTHOR]

This paper provides an overview of the new features of the finite element library deal.II, version 9.5. [ABSTRACT FROM AUTHOR]

This paper provides an overview of the new features of the finite element library deal.II, version 9.4. [ABSTRACT FROM AUTHOR]

To respond to the rapid introduction and development of calcined clays as supplementary cementitious material (SCM), the toolbox of characterization methods for cementitious materials requires extension to raw clay characterization. Borrowing concepts and methods developed in the field of clay mineralogy, this paper outlines the merits and limits of widely accessible characterization techniques for raw clays intended for use as SCM, when calcined. The paper focuses mainly on the identification and quantification of the raw clay mineral components, as these characteristics have important implications for further material processing and performance. General notes are provided on clay sampling and pre-treatment as well as bulk chemical analysis. The main techniques considered are X-ray diffraction, thermal analysis and infrared spectroscopy. Their application on raw clays is introduced, highlighting clay-specific aspects of sample preparation, data acquisition, and processing. Guidelines and interpretation tables are provided to aid in the analysis of the acquired data, while limitations and potential interferences are identified. Options for remote prospection by infrared spectroscopy are included as well. To illustrate the type of information to be gained and the complementarity of the techniques, two representative raw clays are fully characterised. This paper aims to highlight that mineralogical characterization is a feasible and often necessary step in the study and assessment of raw clays that can deliver a wealth of informative data if carried out appropriately. [ABSTRACT FROM AUTHOR]

The use of clays as resource of supplementary cementitious materials (SCMs) for a new generation of low-carbon cements and concretes is currently the subject of intense research efforts. To this purpose, a large number of clay resources have been explored, characterized and evaluated. This paper introduces the basic knowledge and concepts on clay occurrence and clay mineralogy, before presenting up-to-date knowledge on properties and occurrence of clay resources suitable for use as SCMs. Occurrence, distribution and chemical and mineralogical selection criteria are discussed for kaolinitic clays, which often show superior reactivity and performance. 2:1 clay mineral resources have received somewhat less attention as SCM resources, however recent developments indicate significant potential for calcined impure common clays, and are reviewed. An overview of ubiquitous clay mineral-bearing waste materials also identifies important opportunities for alternative clay sourcing in mining or extraction residues, and dredged or excavated sediments. [ABSTRACT FROM AUTHOR]

Sensors in an automated vehicle (AV) can encounter occlusions caused by other traffic, buildings, and vegetation, especially in urban areas. Information from infrastructure sensors sent via vehicle-to-anything communication can help. We have developed and prototypically implemented an infrastructure environment model generated from infrastructure sensors on a multi-access edge computing server on an LTE/5G mobile network. This extends an AV’s field of view and is integrated into the vehicle’s motion planning schemes. In this article, after a description of our approach, we present and discuss real-world results from a pilot site at a public junction that were obtained using prototype AVs. [ABSTRACT FROM AUTHOR]

Treatment of an N-silyl-B-chloro-aminoborane with substoichio-metric quantities of Me3SiOTf afforded B–N coupling, whereas activation with 5 mol% of Ag[Al{OC(CF3)3}4] led to Cl/Me exchange between the boron and the silicon center. Combined experimental and computational studies of the latter process support a chain reaction that is initiated by nucleation-limited chloride abstraction. [ABSTRACT FROM AUTHOR]

The use of calcined clays as supplementary cementitious materials provides the opportunity to significantly reduce the cement industry's carbon burden; however, use at a global scale requires a deep understanding of the extraction and processing of the clays to be used, which will uncover routes to optimise their reactivity. This will enable increased usage of calcined clays as cement replacements, further improving the sustainability of concretes produced with them. Existing technologies can be adopted to produce calcined clays at an industrial scale in many regions around the world. This paper, produced by RILEM TC 282-CCL on calcined clays as supplementary cementitious materials (working group 2), focuses on the production of calcined clays, presents an overview of clay mining, and assesses the current state of the art in clay calcination technology, covering the most relevant aspects from the clay deposit to the factory gate. The energetics and associated carbon footprint of the calcination process are also discussed, and an outlook on clay calcination is presented, discussing the technological advancements required to fulfil future global demand for this material in sustainable infrastructure development. [ABSTRACT FROM AUTHOR]

This paper provides an overview of the new features of the finite element library deal.II, version 9.3. [ABSTRACT FROM AUTHOR]

Calcined clay blended cements play a major role in cement industry's strategy to reduce CO2 emissions. During their hydration, an accelerated aluminate reaction is often observed to affect the sulfate balance. The objective of this study was to provide insights into the influence of different calcined clays on the hydration of cubic tricalcium aluminate (C3A). A cementitious model system consisting of cubic C3A, quartz powder, calcium sulfate and a model pore solution was investigated. The influence of three different calcined clays and one nanolimestone was examined by a successive replacement of the quartz powder and variation of the calcium sulfate. Heat flow and hydrate phase development were followed by isothermal calorimetry and quantitative in‐situ X‐ray diffraction. Accelerated ettringite formation and sulfate depletion were observed for all calcined clays, while the nanolimestone exhibited the opposite effect. It was found that adsorption of SO4 ions and/or Ca‐SO4‐complexes at the surface of calcined clay particles is the main factor inhibiting retardation of the C3A hydration in absence of a silicate reaction. In the Al‐rich systems a retardation through sulfate adjustment seems to be impeded by additional Al ions, which react with Ca adsorbed onto and leached from the C3A surface. [ABSTRACT FROM AUTHOR]

This paper provides an overview of the new features of the finite element library deal.II, version 9.2. [ABSTRACT FROM AUTHOR]

This paper provides an overview of the new features of the finite element library deal.II, version 9.1. [ABSTRACT FROM AUTHOR]

The article titled "Front Cover: 1,2,5-Azadiborolane as a Building Block for Inorganic-Organic Hybrid Polymers" discusses the synthesis of an oligomer as a model for a BCN hybrid polymer. The reaction of the azadiborolane with a disilylated amine resulted in a single B-N coupling event, while the reaction with silylated diamines led to polymerization. The polymer showed a bathochromic shift in the absorption band, indicating p-electron delocalization. X-ray crystallography studies supported this finding. The article acknowledges the individuals responsible for designing the image and provides more information in the Research Article by H. Helten and co-workers. [Extracted from the article]

This article discusses the development of inorganic-organic hybrid polymers with a BN-doped backbone using a modular synthetic approach. The researchers combined different building blocks to create p-conjugated polymers and monodisperse oligomers with tailored properties, such as solid-state and aggregation-induced emission at specific wavelengths. The article provides a polymer sequence and background color illustration to demonstrate the incorporation of different building blocks. For more information, readers can refer to the research article by H. Helten et al. [Extracted from the article]

This paper provides an overview of the new features of the finite element library deal.II version 9.0. [ABSTRACT FROM AUTHOR]

Copyright of Grundwasser is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper introduces a novel framework for model adaptivity in the context of heterogeneous multiscale problems. The framework is based on the idea to interpret model adaptivity as a minimization problem of local error indicators that are derived in the general context of the dual weighted residual (DWR) method. Based on the optimization approach a postprocessing strategy is formulated that lifts the requirement of strict a priori knowledge about applicability and quality of effective models. This allows for the systematic, \goal-oriented" tuning of effective models with respect to a quantity of interest. The framework is tested numerically on elliptic difusion problems with different types of heterogeneous, random coefficients, as well as an advection-difusion problem with a strong microscopic, random advection field. [ABSTRACT FROM AUTHOR]

By formally invoking the Wiener-Hopf method, we explicitly solve a one-dimensional, singular integral equation for the excitation of a slowly decaying electromagnetic wave, called surface plasmon-polariton (SPP), of small wavelength on a semiinfinite, flat conducting sheet irradiated by a plane wave in two spatial dimensions. This setting is germane to wave diffraction by edges of large sheets of single-layer graphene. Our analytical approach includes (i) formulation of a functional equation in the Fourier domain; (ii) evaluation of a split function, which is expressed by a contour integral and is a key ingredient of the Wiener-Hopf factorization; and (iii) extraction of the SPP as a simple-pole residue of a Fourier integral. Our analytical solution is in good agreement with a finite-element numerical computation. [ABSTRACT FROM AUTHOR]

Two isostructural and isoelectronic group VI azide complexes of the general formula [M(η3-allyl)(N3)(bpy)(CO)2] with M = Mo, W and bpy = 2,2′-bipyridine were prepared and fully characterized, including X-ray structure analysis. Both reacted smoothly with electron-poor alkynes such as dimethyl acetylenedicarboxylate (DMAD) and 4,4,4-trifluoro-2-butynoic acid ethyl ester in a catalyst-free room-temperature iClick [3 + 2] cycloaddition reaction. Reaction with phenyl(trifluoromethyl)acetylene, on the other hand, did not lead to any product formation. X-ray structures of the four triazolate complexes isolated showed the monodentate ligand to be N2-coordinated in all cases, which requires a 1,2-shift of the nitrogen from the terminal azide to the triazolate cycloaddition product. On the other hand, a 19F NMR spectroscopic study of the reaction of the fluorinated alkyne with the tungsten azide complex at 27 °C allowed detection of the N1-coordinated intermediate. With this method, the second-order rate constant was determined as (7.3 ± 0.1) × 10−2 M−1 s−1, which compares favorably with that of first-generation compounds such as difluorocyclooctyne (DIFO) used in the strain-promoted azide–alkyne cycloaddition (SPAAC). In contrast, the reaction of the molybdenum analogue was too fast to be studied with NMR methods. Alternatively, solution IR studies revealed pseudo-first order rate constants of 0.4 to 6.5 × 10−3 s−1, which increased in the order of Mo ＞ W and F3C–C≡C–COOEt ＞ DMAD. [ABSTRACT FROM AUTHOR]

This paper provides an overview of the new features of the finite element library deal.II version 8.5. [ABSTRACT FROM AUTHOR]

Singe crystals of a new high-temperature polymorph of NaCaSiO have been obtained from solid state reactions performed at 1300 °C. The basic crystallographic data of this so-called β-phase at ambient conditions are as follows: space group P1 c1, a = 9.0112(5) Å, b = 7.3171(5) Å, c = 10.9723(6) Å, β = 107.720(14)°, V = 689.14(7) Å, Z = 2. The crystals showed twinning by reticular merohedry (mimicking an orthorhombic C-centred unit cell) which was accounted for during data processing and structure solution. Structure determination was accomplished by direct methods. Least-squares refinements resulted in a residual of R(|F|) = 0.043 for 5811 observed reflections with I > 2σ(I). From a structural point of view β-NaCaSiO can be attributed to the group of mixed-anion silicates containing [SiO]-dimers as well as isolated [SiO]-tetrahedra in the ratio 1:2, i.e. more precisely the formula can be written as NaCa[SiO][SiO]. The tetrahedral groups are arranged in layers parallel to (100). Sodium and calcium cations are located between the silicate anions for charge compensation and are coordinated by six to eight nearest oxygen ligands. Alternatively, the structure can be described as a mixed tetrahedral-octahedral framework based on kröhnkite-type [Ca(SiO)O]-chains in which the CaO-octahedra are corner-linked to bridging SiO-tetrahedra. The infinite chains are running parallel to [001] and are concentrated in layers parallel to (010). Adjacent layers are shifted relative to each other by an amount of +δ or −δ along a*. Consequently, a ...ABABAB... stacking sequence is created. A detailed comparison with related structures such as α-NaCaSiO and other ABSiO representatives including topological as well as group theoretical aspects is presented. There are strong indications that monoclinic NaCaSiO mentioned in earlier studies is actually misinterpreted β-NaCaSiO. In addition to the detailed crystallographic analysis of the previously unknown compound our results will also help to improve the interpretation of the phase relationships between the compounds in the ternary system NaO-CaO-SiO which are of interest for several applications related to the field of applied mineralogy and materials science. [ABSTRACT FROM AUTHOR]

This paper provides an overview of the new features of the finite element library deal.II version 8.4. [ABSTRACT FROM AUTHOR]

This paper introduces an framework for adaptivity for a class of heterogeneous multiscale finite element methods for elliptic problems, which is suitable for a posteriori error estimation with separated quantification of the model error as well as the macroscopic and microscopic discretization errors. The method is derived within a general framework for 'goal-oriented' adaptivity, the so-called Dual Weighted Residual (DWR) method. This allows for a systematic a posteriori balancing of multiscale modeling and discretization. The developed method is tested numerically at elliptic diffusion problems for different types of heterogeneous oscillatory coefficients. [ABSTRACT FROM AUTHOR]

Copyright of Chemie Ingenieur Technik (CIT) is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The purpose of the present study was to assess the hazard potentials of contaminated suspended particulate matter (SPM) sampled during a flood event for floodplain soils using in vitro bioassays and chemical analysis. Sediment-contact tests were performed to evaluate the direct exposure of organisms to native soils and SPM at two different trophic levels. For comparison, acetonic extracts were tested using both contact tests and additionally two cell-based biotests for cytotoxicity and Ah receptor-mediated activity (EROD-Assay). The sediment-contact tests were carried out with the dehydrogenase assay with Arthrobacter globiformis and the fish embryo assay with Danio rerio. The results of this study clearly document that native samples may well be significantly more effective than corresponding extracts in the bacteria contact assay or the fish embryo test. These results question the commonly accepted concept that acetonic extracts are likely to overestimate the toxicity of soil and SPM samples. Likewise, the priority organic compounds analyzed failed to fully explain the toxic potential of the samples. The outcomes of this study revealed the insufficient knowledge regarding the relationship between the different exposure pathways. Finally, there is concern about adverse effects by settling suspended particulate matter and remobilized sediments in frequently inundated floodplain soils due to an increase of the hazard potential, if compared with infrequently inundated floodplain soils. We showed that the settling of SPM and sediments revealed a significant impact on the dioxin-like potencies of riparian soils. [ABSTRACT FROM AUTHOR]

Copyright of Grundwasser is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)