Recent publications
Introduction
Medical syringes are widely used in hospitals to store and administer drugs, and the contact time between the drugs and these syringes can vary from a few minutes to several weeks like for pharmaceutical preparations. The aim of this comparative study was to evaluate the potential sorption phenomena occurring between three drugs (paracetamol, diazepam and insulin aspart) and polypropylene syringes (PP) or syringes made of Cyclic Olefin Copolymer (COC).
Materials and methods
50 mL 3-part syringes made of either COC with crosslinked silicone on the barrel inner surface (COC-CLS) and a bromobutyl plunger seal, or PP lubricated with silicone oil (PP-SOL) with a polyisoprene plunger seal were used.
Results
COC-CLS syringes induced less sorption of diazepam and insulin than PP-SOL syringes and the plunger seal material seemed to be the main cause of these interactions. An alkalinization of the medications in contact with the PP-SOL syringes was observed. It could be caused by leachable compounds and should be investigated further.
Conclusion
This work shows once again that it is essential to consider content-container interactions to help improve the safe use of parenteral drugs.
Hybrid solid electrolytes (HSEs), namely mixtures of polymer and inorganic
electrolytes, have supposedly improved properties with respect to inorganic
and polymer electrolytes. In practice, HSEs often show ionic conductivity
below expectations, as the high interface resistance limits the contribution of
inorganic electrolyte particles to the charge transport process. In this study,
the transport properties of a series of HSEs containing Li(1+x)AlxTi(2–x)(PO4)3
(LATP) as Li+-conducting filler are analyzed. The occurrence of Li+ exchange
across the two phases is proved by isotope exchange experiment, coupled
with 6Li/7Li nuclear magnetic resonance (NMR), and by 2D 6Li exchange
spectroscopy (EXSY), which gives a time constant for Li+ exchange of about
50 ms at 60 °C. Electrochemical impedance spectroscopy (EIS) distinguishes
a short-range and a long-range conductivity, the latter decreasing with LATP
concentration. LATP particles contribute to the overall conductivity only at
high temperatures and at high LATP concentrations. Pulsed field gradient
(PFG)-NMR suggests a selective decrease of the anions’ diffusivity at high
temperatures, translating into a marginal increase of the Li+ transference
number. Although the transport properties are only marginally affected,
addition of moderate amounts of LATP to polymer electrolytes enhances their
mechanical properties, thus improving the plating/stripping performance and
processability.
Three machine-learned potentials (SNAP, NNP, ACE) were created from the same training set of DFT energies and forces for a total of 1024 structures. DFT calculations were performed with the PBE functional and the Grimme D3 corrections. DFT energies can be reproduced within a few meV by the potentials. The potentials are evaluated how they predict structures, thermal expansion coefficients, and ionic conductivities of α- and β-eucryptite. Structures and thermal expansion coefficients are in good agreement with experimental values. All potentials reproduce the negative thermal expansion coefficient along the c axis of β-eucryptite, although only ACE calculates a negative thermal expansion coefficient for the volume. Ionic conductivities can be predicted only qualitatively correct. Molecular dynamics simulations performed with some of the potentials at higher temperatures can result in unphysical structures.
As the industrialization of waveguide based AR devices is progressing, considerations around design based shaping of waveguides as well as robustness move into focus. A promising approach for scalable free‐form cutting with high strength and precision is the utilization of ultrashort pulsed lasers. Various possible laser process parameters and different material compositions of high index glasses are challenging the optimization with respect to strength of the glass. SCHOTT AG and 3D‐Micromac AG optimized a separation process towards high and predictable bending strength and integrated it into a modular machine concept freely scalable from lab to mass production use.
Lithium metal-based solid-state batteries (SSBs) have attracted much attention due to their potentially higher energy densities and improved safety compared with lithium-ion batteries. One of the most promising solid electrolytes, garnet-type Li7La3Zr2O12 (LLZO), has been investigated intensively in recent years. It enables the use of a lithium metal anode, but its application is still challenging because of lithium dendrites that grow at voids, cracks, and grain boundaries of sintered bodies during cycling of the battery cell. In this work, glass-ceramic Ta-doped LLZO produced in a unique melting process was investigated. Upon cooling, an amorphous phase is generated intrinsically, whose composition and fraction are adjusted during the process. Herein, it was set to about 4 wt % containing Li2O and a Li2O-SiO2 phase. During sintering, it was shown to segregate into the grain boundaries and decrease porosity via liquid phase sintering. Sintering temperature and sintering time were found to be reduced compared with the LLZO fabricated by a solid-state reaction while maintaining high density and ionic conductivity. The glass-ceramic sintered at 1130 °C for 0.5 h showed a room-temperature ionic conductivity of 0.64 mS cm-1. Most importantly, the evenly distributed amorphous phase along the grain boundaries effectively hinders lithium dendrite growth. Besides mechanically blocking pores and voids, it helps to prevent inhomogeneous distribution of current density. The critical current density (CCD) of the Li|LLZTO|Li symmetric cell was determined as 1.15 mA cm-2, and in situ lithium plating experiments in a scanning electron microscope revealed superior dendrite stability properties. Therefore, this work provides a promising strategy to prepare a dense and dendrite-suppressing solid electrolyte for future implementation in SSBs.
In many applications, the spatial refractive index variation – called homogeneity – within a measurement aperture either in one or two directions is important. Typical application examples are prisms in ultra-precision metrology with stability in multiple directions. Large lenses are used in artificial laser guide star systems for atmospheric correction in large telescopes. The challenge of enabling highest refractive index homogeneities requires tight control of all production steps from melting to hot forming and fine annealing. Large optical formats can be produced as singular castings in moulds up to 1.2 m in diameter and 250 mm thickness. Smaller formats are available as blocks produced in dimensions of approx. 250 x 250 x 180 mm3. A more economic and ecologic way is the production of continuous strips of glass up to approx. 500 mm width and 120 mm thickness. Recently SCHOTT has improved the homogeneity of these continuously produced jumbo strips significantly. Now homogeneity of up to H4 quality (2 ppm index maximum variation) can be provided on apertures up to approx. 900 mm x 500 mm. This paper gives an insight overview on the latest results and current state of this topic at the optical glass manufacturer SCHOTT.
A group of the DECHEMA working group “Single‐Use Technology in Biopharmaceutical Manufacture” is investigating the potential use of single‐use systems for cellular agricultural applications. The preliminary results are summarized in this article. In the biopharmaceutical industry, single‐use systems are well established alongside their reusable counterparts. The DECHEMA working group “Single‐Use Technology in Biopharmaceutical Manufacture” is currently investigating whether single‐use systems can also be used for cellular agricultural applications and preliminary results are presented.
Cutting glass to shape with ultra short laser pulses is nowadays a well established industrial process. Pulses with an elongated straight focal volume (line focus) are used to modify the workpiece throughout its entire depth with one single laser shot. At the same time, processed glass is often required to have a seamed or round edge, which usually requires an extra grinding step. Here we demonstrate that curved line foci can be used to combine cutting and edge shaping of glass sheets in one laser process. We reconsider the Airy-Gauss beam for this purpose, and suggest modifications to the beam profile to avoid unwanted effects, in particular an asymmetric laser modification of the glass sheet. We provide a combined experimental and numerical analysis of the laser process, and show a symmetric convex edge created in a 920μm thick glass sheet.
Real-time Anomaly Detection is of great importance in industrial applications in order to have high-quality production and avoid downtime or failure of the system. In this paper, we study the application of anomaly detection over the multivariate data collected from Glass Production Industry. Our experiments utilize and compare different Unsupervised multivariate time series Anomaly Detection and Localization algorithms that have already demonstrated significant results on the state-of-the-art data sets. We propose a two-level multivariate anomaly detection approach that not only detects anomalous events in the production line but also categorize the different type of anomalies based on statistical pattern recognition. Furthermore, we localize the anomalous sensors by utilizing Explainable-AI approaches to help better decision-making in glass production monitoring. In this work, we propose an efficient pipeline for Anomaly Detection, Categorization and Localization which the experiments show promising results.
Glass has been shown to be a capable core substrate material for high-frequency applications. In this article, we examine the capabilities of ultra-thin glass as a material that can be used for high-frequency flexible applications. The two stack-ups discussed in the work presented are 60
$\mu \text{m}$
in total thickness with a core glass substrate (Schott AF32) of 30
$\mu \text{m}$
thickness. One stack-up uses 15
$\mu \text{m}$
JSR GT-N01 as a buildup dielectric on each side of the glass and the other uses 15
$\mu \text{m}$
Taiyo Ink photo imageable dielectric (PID). Both stack-ups have been characterized to 110 GHz and have shown to have comparable performance to materials used in this frequency range. This work then focuses on the mechanical characterization of these stack-ups using free arc bending. The free arc bending tests show that both ultra-thin glass stack-ups are suitable for bending applications as the tested samples can bend to a panel separation below 33% of the sample’s total length. This article concludes that the ultra-thin glass stack-ups are suitable for high-frequency flexible applications because the electrical performance is comparable to other high-frequency rigid materials while exhibiting their flexible capabilities.
Piezoelectric force microscopy (PFM) has demonstrated to be a powerful tool to characterize ferroelectric materials. However, extrinsic effects, most notably, those resulting from surface charges, often mask or mirror genuine piezoelectric response, challenging PFM data understanding. The contribution of surface charges to PFM signal is commonly compensated by using appropriate external bias voltage, which is ad-hoc selected and sample dependent. Here, we determine the compensating voltage in thin films of different ferroelectric materials and we compare with the corresponding I-V characteristics recorded using suitable electrodes. It turns out that the sign and magnitude of the bias voltage required to compensate the surface charges are related to the asymmetry of the I-V characteristics. We propose that this relation results from the fact that the semiconducting properties of the material determine both the I-V dependence, and the sign of charged adsorbates. We show how to make use of this correlation to predict the required compensation voltage of a non-ferroelectric material and we show that spurious piezoelectric-like contributions are largely cancelled. The results provide guidelines to mitigate common extrinsic contributions in PFM imaging.
In this chapter the diverse properties of glass are described, especially focused on the application of thin and ultra‐thin (≤ 100 μm) substrates. The first sections give an overview of the most important manufacturing processes and their advantages and disadvantages, followed by a characterization of typical chemical, physical, and mechanical properties. Next, the authors discuss possibilities for surfaces that are as free of both defects and contaminations as possible. Different glass types and the typical applications are presented in detail, including glass ceramics and photosensitive glass. The last section demonstrates the options for new applications by microstructuring with high variability of the structuring features.
Planar high‐refractive‐index glass wafers are the backbone of leading Augmented and Mixed Reality devices. They route the virtual image to the user's eye, while helping to keep the form factor small. While the glass characteristics directly affect fundamental design parameters such as field of view, the optical system of the wafer with its interfaces as a whole determines the image quality. Here we report on latest achievements both on the glass and on the wafer level that allow for significant weight reduction without sacrificing optical performance. Based on a state‐of‐the‐ art two layer device with a refractive index of 1.9, an overall weight reduction >20% is feasible. This creates a basis to drive AR devices from niche applications toward more widespread commercial adoption.
Mechanisms, feedbacks and resulting non-linearity during silicate glass alteration in a hyperalkaline carbonate solution were studied through hyperspectral Raman imaging of heated fluid-cells. Our experimental setup enabled in operando visualization and rate measurements of glass dissolution and secondary phase precipitation, complemented by spectral characterization of the phases involved and semi-quantitative monitoring of the ionic strength of the solution close to the glass interface. After initial congruent dissolution of the Ba-bearing soda-lime boroaluminosilicate glass, the formation of a crystalline, saponite-based surface alteration layer (SAL), as well as subsequent zeolite precipitation, witherite coating, and carbonate precipitation within pore spaces of the saponite layer were observed. Two in operando experiments were conducted at ∼ 90°C for 180 and 260 h that otherwise solely differed in the solution volume (SV) while keeping the surface area constant. The high SV experiment exhibited a transient upward excursion of initial dissolution rates, followed by continuously rapid glass dissolution along with slow SAL growth and sustained oscillations in ionic strength. Contrastingly, in the low SV experiment, glass dissolution monotonically decreased after the onset of rapid SAL growth and no sustained oscillations were observed. We find that growth conditions and resulting properties of the SAL exert dominant, non-linear effects on the evolution of glass dissolution rates. In turn, SAL formation depends on nucleation/growth kinetics and the accumulation of glass-derived solutes at the reaction front. Both, dissolution and precipitation, feedback with solution chemistry and transport processes, together controlling the evolution of the corrosion process. Additionally, fracturing, delamination, and the evolution of surface morphology may affect glass dissolution rates and transport pathways. Such interpretations of decelerating reaction rates in response to the growth of a protective layer are consistent in micro-scale experiments and in outcrop- to global-scale observations, as is the accelerating effect of surface area creation by physical disruption and morphology. Thus, these µm-scale mechanistic insights could help elucidating local to global environmental feedbacks (e.g., erosion or weathering patterns) as well as process dynamics in engineered environments (e.g., nuclear waste disposal) and may assist the improvement predictive models.
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