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Stability studies are crucial for pharmaceutical product registration, providing vital data to assess batch-to-batch consistency, monitor critical quality attributes, and ensure the product's quality, safety, and efficacy over its entire shelf life. Identifying potential issues such as potential out-of-specification (OOS) results and ensuring data quality is often facilitated by employing objective methods for trend analysis of stability data. The goal of the research was to explore the advantages of trend analysis in stability studies, highlighting its significance in forecasting OOS results and ensuring the consistent performance of pharmaceutical products within their estimated shelf life. To evaluate stability data and find the pattern of data that indicates change over time, stability studies for Lisinopril/Amlodipine tablets 20mg/10mg were subjected to trending analysis based on data from annual or routine stability studies. The trending analysis was performed to evaluate whether the data demonstrates increasing or decreasing trend (change of mean) for the stability indicating parameters over time or the data indicate no discernible change at all, as well as predicting potential OOS results during shelf life. Regression analysis as a statistical tool for trending analysis, is considered an appropriate approach to evaluating the stability data for a quantitative attribute.

The five‐choice serial reaction time task (5CSRTT) is a test of attention that provides a well‐validated ancillary measure of impulsive action, measured by premature responses. The task has been adapted for mice in touchscreen operant boxes, which is thought to offer improved test–retest reliability. Few studies have assessed the long‐term stability of performance, including premature responding in this version of the task. We used the touchscreen 5CSRTT to conduct longitudinal testing of stability of premature responding following repeated behavioral and pharmacological manipulations. Male C57BL/6J mice were trained on a baseline version of the 5CSRTT. They were then tested on versions of the task in which the stimulus duration was reduced, and inter‐trial intervals were elongated or varied within‐session. Premature responding was subsequently tested following administration of pharmacological agents known to bi‐directionally affect attention and impulsive action—cocaine, atomoxetine, and yohimbine. Mice were lastly re‐tested 6 months later using the 5CSRTT with elongated inter‐trial intervals. A reduced stimulus duration impacted attention, with reduced accuracy and increased omissions, but had no effect on premature responding. Both elongating and varying the inter‐trial interval within‐session increased premature responses. Mice showed similar and stable levels of increased premature responding 6 months later. Cocaine increased premature responding, though less than previously reported in rats. Atomoxetine reduced premature responding. Yohimbine had no effect on premature responding in the baseline task but decreased premature responding when tested using an elongated inter‐trial interval. Overall, these results highlight that the touch screen adaptation of the 5CSRTT is an effective method for longitudinal testing of attention and impulsive action and remains sensitive to performance changes arising from repeated pharmacological and behavioral challenges. [ABSTRACT FROM AUTHOR]

Solar-driven seawater desalination has been one of the most promising approaches to alleviate energy pressure, freshwater resource shortage and environmental crisis. Solar interfacial evaporation can be confined the heat into the evaporation surface, in order to avoid the bulk water heating for the energy saving. In this study, the dopamine was used to modify the natural corncobs, in order to reduce the degradation of natural biomass for the high evaporation efficiency in seawater desalination. A solar interfacial evaporator was prepared to integrate the photothermal conversion, water transportation, and thermal insulation. The substrate was selected as the carbon black-cellulose film coating on the modified corncob. The light absorptance of natural corncobs with/without the carbon black-cellulose film were measured using a UV-visible spectrophotometer. The corncobs with carbon black-cellulose film was significantly improved the absorption performance, with an average absorption rate of 94% in the entire solar radiation band. The contact angle of water droplets on the modified corncobs was about 29.9°, which was reduced significantly. The hydrophilicity of the modified corncobs was enhanced for the transfer of water in the corncobs. The water transportation along the corncob was visually displayed using infrared images. Once the bottom of the corncob came into the contact with water, no water transport was observed within the unmodified corncob in 60 min. By contrast, the water was observed at a lower temperature along the dopamine modified corncob, indicating the better performance of water transport than before. The evaporation mass of modified and unmodified corncobs was measured under the same conditions. Both the corncobs were covered with the carbon black-cellulose film. The evaporation rates were 1.38 and 1.25 kg/(m²·h) in the modified and unmodified corncob evaporator respectively. There was the increase by about 10.4% in the modified corncob, compared with unmodified ones. Another indicator was the stability of evaporators in seawater environment under cyclic operation for a long time, in order to evaluate the performance of evaporators. There was no salt crystallization on the surface after continuous irradiation of the modified corncob evaporator with a light intensity of 1 kW/m² for 8 hours. 30 cycle experiments were conducted on the modified corncob evaporator. The evaporation rate was 1.374 kg/(m²·h) in the first test, and the second after 30 cycles, the evaporation rate was 1.36 kg/(m²·h). The fluctuation of evaporation rate was with 1% over the 30 cycle experiments, indicating the stable evaporation rate. Moreover, the adhesion of dopamine was remained intact without salt deposition in the multiple cyclic experiments. There was no softening or material degradation in the modified corncob under seawater environments, indicating the long-term stability. Seawater distillation experiments was conducted in outdoor environments, in order to analyze the water production and ion removal of corncob evaporators. The daily water production reached 10.171 kg/m². The various ions in seawater and condensate were measured using the Varian 720-ES inductively coupled plasma emission spectrometer (ICP-OES). The concentrations of the main ions Na+, K+, Mg2+, and Ca2+ in condensate significantly decreased by about four orders of magnitude, reaching the limits of the drinking standards released by the World Health Organization (WHO). The evaporating seawater through corncobs can obtain the fresh water to fully meet drinking standards. The modified corncob evaporator was simple preparation, cost-effective and stable evaporation performance. The finding can provide an effective way to expand the application of biomass materials in the field of seawater desalination. [ABSTRACT FROM AUTHOR]

The green hydrogen production via water splitting is a highly promising method for eventual fossil fuel replacement, which causes many harmful products. Water electrolysis is one particularly dependable method of bridging primary renewable energy with stable hydrogen energy. In this study, the Fe 2 O 3 @CuO-400 is fabricated via simple hydrothermal process and is employed for green hydrogen production. The structure-engineered Fe 2 O 3 @CuO-400 exhibits enhanced activity, achieving a lower overpotential of 130 mV during 10 mA cm−2 and a smaller Tafel slope of 77 mV/dec for hydrogen evolution reaction. Conversely, the Fe 2 O 3 @CuO-400 nanocomposite exhibits 230 mV of overpotential & 54 mV/dec of Tafel slope for OER. The electronic interaction between Fe 2 O 3 and CuO inside the heterojunction adjusted the electrical configuration between Cu and Fe improving the kinetics of the reaction, which enhanced the efficiency of hydrogen production. Hence, this study proposes a new avenue for producing heterostructure-based catalysts, which are beneficial for electrochemical applications in future. [Display omitted] • The Fe 2 O 3 @CuO-400 is prepared for efficient OER and HER electrocatalyst. • The electronic interaction among Fe 2 O 3 and CuO improve the OER kinetics. • The fabricated Fe 2 O 3 @CuO-400 achieve a 130 mV overpotential at 10 mA cm−2 for HER. • The synthesized Fe 2 O 3 @CuO-400 achieve Tafel slope of 77 mV/dec for HER. • The Fe 2 O 3 @CuO-400 nanocomposite exhibits 230 mV & 54 mV/dec for OER. [ABSTRACT FROM AUTHOR]

As a promising energy conversion device, solid oxide cell can realize efficient conversion between chemical energy and electrical energy under solid oxide fuel cell and solid oxide electrolysis cell mode. In this work, a Ruddlesden-Popper type oxide Pr 1.5 La 0. 5 Ni 0. 8 Cu 0. 2 O 4+δ (PLNC) with good mixed ionic-electronic conductivity is investigated as a dual functional air electrode for SOC. The results confirm that the peak power densities of the LSGM electrolyte supported cell with PLNC-GDC composite air electrode can reach 1.127, 0.911, 0.675 and 0.446 W cm−2 at 800, 750, 700 and 650 °C, respectively. Meanwhile, the cell possesses excellent durability for nearly 200 h under a constant current density of 400 mA cm−2 at 700 °C. The cell also shows superior electrolysis current density of 1.54 A cm−2 under electrolysis voltage of 1.3 V at 800 °C. The study demonstrates that PLNC is a promising dual functional air electrode material with excellent oxygen reduction reaction and oxygen evolution reaction activity for oxygen electrocatalytic reaction. • La- and Cu-doped Pr 1.5 La 0. 5 Ni 0. 8 Cu 0. 2 O 4+δ (PLNC) is investigated as a dual functional air electrode. • LSGM electrolyte supported cell with PLNC air electrode can achieve 1.127 W cm−2 at 800 °C in SOFC mode. • The cell shows electrolysis current density of 1.54 A cm−2 under 1.3 V at 800 °C in SOEC mode. • The cell possesses excellent durability for long term test in SOFC and SOEC mode. [ABSTRACT FROM AUTHOR]

Copyright of Macedonian Pharmaceutical Bulletin / Makedonsko Farmacevtski Bilten is the property of Macedonian Pharmaceutical Association 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.)

Amorphous solid dispersions (ASDs) are a widely used formulation technology for poorly water-soluble active pharmaceutical ingredients (API). Depending on the API-polymer combination and API load in the ASD, the amorphous API might be thermodynamically metastable and crystallize over time. The crystallization onset is one critical factor that can define the shelf life of the ASD. Thus, for ASD formulations, long-term stability against crystallization of the API is of particular interest. This work presents a method for predicting the long-term physical stability of ASDs (crystallization onset time). The new approach combines the Johnson-Mehl-Avrami-Kolmogorov (JMAK) equation with classical nucleation theory. The shelf life predicted using the new approach depends on supersaturation (determined with PC-SAFT), viscosity (determined with WLF equation or Arrhenius equation) and two specific model parameters k’ and B. The latter were fitted to a few fast crystallization-kinetics measurements above the glass transition of the ASD. An additional crystallization-kinetics measurement below the glass-transition temperature of the ASD was used to determine the Arrhenius parameters. Once all parameters are determined for a given API/polymer combination and manufacturing method, they are valid for any API load, temperature, and RH. The proposed approach allows predicting the shelf life (crystallization onset) of a potential ASD in early stage of development within a few days. It was successfully verified for ASDs stored at 25 °C and 10% RH or 60% RH.

Metal sulfides and graphene oxide nanocomposites have recently has garnered considerable attention in the field of electrochemical energy storage devices. In this study, we synthesized a cadmium sulfide/graphene oxide (CdS/GO) nanocomposite using different contents of graphene oxide (0.01, 0.02, 0.03 and 0.04 g) with fixed concentartion of CdS (0.3 g) via Solid-State Reaction (SSR) method. CdS/GO composite were subsequently investigated to be used as electrode materials for supercapacitors. Notably, the optimized electrode CdS/GO-0.04 electrode demonstrated superior capacitive performance compare to individual CdS and their composites with GO. In a symmetric supercapacitor configuration, the CdS/GO-0.04 cathode demonstrated a specific capacitance of 211.5 F g ^−1 at a scan rate of 1.5 A g ^−1 and maintained 93% of its capacitance after 1,000 cycles at a current density of 5 A g ^−1 , indicating excellent cycling stability. The significantly improved capacitive performance of CdS/GO-0.04 can be primarily attributed to the synergistic interaction between CdS and GO particles, enhanced conductivity, and the relatively larger surface area of the composites. These findings suggest that CdS/GO nanocomposites hold great promise as electrode materials for high-performance energy storage applications.

Copyright of Duzce University Journal of Science & Technology is the property of Duzce University Journal of Science & Technology 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.)

Membrane technologies have been expanded to treat seawater, brine water, wastewater, and polluted water to provide clean water. In membrane distillation (MD) application, a membrane with low surface free energy is preferable to prevent membrane wetting. Thus, the pristine membrane was often modified with functional material to enhance the membrane performance during operation. In this paper, the mechanism of MD is briefly described according to different membrane configurations. Additionally, case studies for pilot plant MD were discussed. This is followed by the membrane fabrication techniques, functional material used for membrane modification and application of functional membrane in MD system. Finally, a future outlook and conclusion were made based on the review. [ABSTRACT FROM AUTHOR]

Abstract There is frequent debate over the long-term stability of calibration specimens. It is an essential component of monitoring, especially for X-ray diffraction equipment used to determine residual stresses. If residual stresses are stable, a second consideration is that the residual stress should not be close to 0 MPa. If such specimens are available for monitoring, it is more sensitive concerning changes. These are key requirements when developing calibration specimens. In this study five specimens were observed, one of them was tested for more than 20 years. The stresses were determined with X-ray diffractometers. In the last four years two different X-ray methods for determination were used. It can be shown that high compressive residual stress does not change in steel if the specimens had no dynamic or static load and were stored under normal laboratory conditions. Article Highlights Finding a material in which compressive residual stress is stable Showing that the stability of compressive residual stress is over a long term The stability of the compressive residual stress is in a great range

Bacterial cellulose (BC) produced by certain bacteria has the potential to be used in many different areas. Despite its advantageous properties compared to plant cellulose, such as high purity, mechanical strength, nanofiber mesh structure, and high-water holding capacity, its production through a biotechnological process prevents it from competing with plant counterparts in terms of cost-effectiveness. Therefore, studies have focused on the development of culture media with cost-effective BC production methods and the production of high value-added products from BC. In this study, it was aimed to develop a taurine-loaded moisturizing facial mask with antioxidant properties based on BC's high-water retention and chemical retention capacity. BC facial mask samples were characterized by Scanning Electron Microscopy (SEM) imaging, Fourier Transform Infrared (FTIR) Spectroscopy, Differential Scanning Calorimetry (DSC), Liquid Chromatography–Mass spectrometry (LC–MS), microbial and mechanical stability tests, as well as cytotoxicity tests. According to our results, produced facial mask samples did not show any cytotoxic effect on human keratinocyte (HS2) or mouse fibroblast (L-929) cell lines; it has high thermal stability, which makes it suitable for different sterilization techniques including sterilization by heat treatment. Taurine release (over 2 µg/mL in 5 min) and microbial stability tests (no bacterial growth observed) of packaged products kept at 40 and 25 °C for 6 months have shown that the product preserves its characteristics for a long time. In conclusion "bacterial cellulose-based facial masks" are suitable for use as a facial mask, and they can be used for moisturizing and antioxidant properties by means of taurine. [ABSTRACT FROM AUTHOR]

[Display omitted] • The change of CA over time on laser micro-structured surfaces is investigated. • The relationship between CA and chemistry was discussed by model description. • The coefficients in the model were obtained by multiple regression analysis. • The reason for CA becoming high is related to the carbon and oxygen-(metal oxide). • The reason for CA keeping low is related to the effect of oxygen-(layer). In recent years, control of the wettability of metal surfaces by laser micro-structuring has attracted much attention. In particular, for applying to industrial applications, long-term stability of wettability is required for metal surfaces by laser micro-structuring, since the wettability of the surface changes over time. In this study, the influences of various chemical components on contact angle (CA) changes over time were quantitatively investigated using a model based on multiple regression analysis. For this purpose, this study investigated the CA and chemical components of laser micro-structured stainless steel 304 surfaces 40 and 80 days after laser micro-structuring. In the end, the reason for the CA becoming high was related to the carbon-C–C(C–H), carbon-(polar), and oxygen-(metal oxide). Moreover, the reason for the CA keeping low for a long time was related to the effect of oxygen-(layer). [ABSTRACT FROM AUTHOR]

Although there have been significant advances in the stability of perovskite solar cells through encapsulation techniques to remove extrinsic degradation factors, such as moisture and oxygen, irreversible photo‐degradation originating from intrinsic defects is still challenging and remains elusive. Herein, the photo‐aging mechanism due to intrinsic defects is investigated in nitrogen‐filled conditions, excluding extrinsic degradation factors. Devices with similar power conversion efficiencies (PCE) of 21%, but with different Fermi levels in the perovskite films, via controlling the self‐doping effect, have been investigated. Opto‐electronic investigations and depth profiles of the elemental constituents show that after photo‐aging, strain relaxation in the perovskite lattice and a Fermi level shift towards conduction band edge are observed, implying the formation of new defect states in Pb‐rich devices. Furthermore, thermal admittance spectroscopy measurement of the devices suggests that the formation of the deep‐traps in the perovskite leads to irreversible degradation. Thin‐film solar cells that are relatively Pb‐deficient (FA‐rich) exhibit improved long‐term stability, retaining over 90% of their initial PCE during 500 h of continuous 1‐Sun illumination. This study suggests passivation of the Pb‐I related antisite defects near the grain boundaries and the interface is crucial for the fabrication of solar cells with enhanced long‐term stability. [ABSTRACT FROM AUTHOR]

Turkish accelerator and radiation laboratory (TARLA) is an accelerator based oscillator mode free electron laser (FEL) facility under construction. The acceleration beamline includes a fundamental buncher (FB) in order to confine the electron beam into a compressed bunch. In this study, we demonstrate the commissioning tests of 500 W RF amplifier powering FB and present the phase stability dependence on the pressure and temperature of the water cooling line under long time run conditions. As the disturbing effects break down the synchronization between the particle and RF power during acceleration, the reasons disquieting the stability of the RF amplifier are investigated. One reason which causes disturbance in the stability is the variation in the phase of the output power. Phase variation of the output power of the RF amplifier which was measured as ~10 deg/°C in average initially, which was beyond permitted variation levels by the controller electronics, namely the low level RF system (LLRF), is decreased to less than ~0.45 deg/°C by incorporating a phase shifter. In addition, this phase variation reduction is accompanied with a reflected power at the output of the RF amplifier decline from 4.3 W (36.33 dBm) down to 3 mW (4.7 dBm) by utilizing a circulator, which is also important and desirable in terms of protection of the electronics in the long term run. As ensuring phase stability in the output power is very important, this work may serve as a guide since the documentation regarding the output power dependence of the water cooling line for long term run is very limited. [ABSTRACT FROM AUTHOR]

All-inorganic cesium lead halide based perovskite nanocrystals (PNCs) exhibit promising optoelectronic properties, but their poor stability and anion exchange reaction limit their broad commercial applications. Herein, we demonstrated the successful synthesis of blue-green-red emitting CsPbX3 (X = Cl/Br, Br, and Br/I) PNCs via hot injection method, followed by silica-coating and embedding in poly(methylmethacrylate) (PMMA) matrix. The photoluminescence (PL) spectra of SiO2/PMMA-coated PNCs can be tuned continuously by regulating precursor composition ratio, from blue (CsPb(Cl0.5/Br0.5)3; 460 nm) to red (CsPb(Br0.4/I0.6)3 via green (CsPbBr3; 519 nm). The PNCs composite films exhibit improved stability (thermal-, moisture-, and photo-stability) because of the barrier formed by SiO2/PMMA coating and also displayed exceptional photoluminescent quantum yield (PLQY of blue, green, and red-emitting SiO2/PMMA coated PNCs are 37%, 86%, and 71%, respectively) with longer lifetimes inhibiting anion exchange. Eventually, the PNCs-encapsulated SiO2/PMMA composite films were integrated into the UV LED chip as down-converting materials to construct a prototype white-peLED unit. The designed white-peLED unit demonstrated bright white light generating CIE coordinates (0.349, 0.350), a luminous efficiency (LE) of 39.2% and a color rendering index (CRI) of 84.7. The wide color gamut of 121.47% of NTSC and 98.56% of Rec. 2020 is also achieved with the built w-LED system. Therefore, the results demonstrated that CsPbX3 (X = Cl/Br, Br, and Br/I) PNCs@SiO2/PMMA composite films can be employed as efficient UV to visible color conversion materials for white-LEDs and backlighting. [ABSTRACT FROM AUTHOR]

Long term stability, high responsivity, and fast response speed are essential for the commercialization of graphene photodetectors (GPDs). In this work, a parylene/graphene UV photodetector with long term stability, ultrahigh responsivity and fast response speed, is demonstrated. Parylene as a stable physical and chemical insulating layer reduces the environmental sensitivity of graphene, and enhances the performances of GPDs. In addition, utilizing bilayer electrodes reduces the buckling and damage of graphene after transferring. The parylene/graphene UV photodetector exhibits an ultrahigh responsivity of 5.82 × 10 5 AW -1 under 325 nm light irradiation at 1 V bias. Additionally, it shows a fast response speed with a rise time of 80 μ s and a fall time of 17 μ s, and a long term stability at 405 nm wavelength which is absent in the device without parylene. The parylene/graphene UV photodetector possesses superior performances. This paves the way for the commercial application of the high-performance graphene hybrid photodetectors, and provides a practical method for maintaining the long term stability of two dimensional (2D) materials., (© 2024 IOP Publishing Ltd.)

A process called EquiAsh® was developed and tested on a large scale. This process aims at upgrading incinerator bottom ash into a long term environmentally safe and stable product. Driven by the agreement between the incinerator branch and the Dutch government in a 'Green Deal', the leaching behavior of bottom ash needs improvement. The leaching of metals and salts must be lowered. EquiAsh®, which is a combination of carbonation (accelerated aging), washing and further mineralization, realizes a safe and stable product now and in the future. The bottom ash is in equilibrium with the atmosphere and the pH is stabilized at values around 8.5. Large scale experiments with 1.000–1.300 ton incinerator bottom ash are performed. These experiments give insight into the changes in leaching of metals and salts. In the end, the bottom ash fulfills the Dutch leaching criteria for a freely applicable building material. [ABSTRACT FROM AUTHOR]

• Identify O/W emulsion gel and emulsion glass w and w/o the addition of gelator. • The O/W emulsion glass with scanty-water was successfully fabricated. • Two methods for forming emulsion glass with low energy consumption were proposed. • One approach is associated with the growth of glass nuclei in the oil environment. • Another method induces direct transformation from emulsion to glass by adding oil. The solid-like oil-in-water (O/W) emulsion can be classified into two types, gelator-induced gel and gelator-free glass, based on the requirement of gelator addition and solidification mechanisms. In this work, the O/W emulsion glass with scanty-water belonging to the gelator-free type was successfully fabricated through a low-energy process even when the content of aqueous surfactant solution was as low as 1 wt%. In an attempt to develop this scanty-water O/W glass, two newly designed approaches subject to mechanical agitation were proposed. The first approach of glass formation was induced by the growth of glass nuclei, which is similar to the mechanism of crystal growth. In the second approach, the water content in the emulsion was diluted by oil addition, leading to the direct transformation from emulsion to glass. Both approaches undergo a crossover associated with the jamming transition. According to rheological measurements, our emulsion glasses possess solid-like behaviors such as elastic modulus and yield stress. Moreover, the O/W glass with scanty-water can be strengthened by reducing the water content. [ABSTRACT FROM AUTHOR]

The surface chemistry of colloidal cesium lead bromide (CsPbBr3) nanocrystals is decisive in determining the stability and the final morphology of this class of materials, characterized by ionic structure and a high defect tolerance factor. Here, the high sensitivity of purified colloidal nanocubes of CsPbBr3 to diverse environmental condition (solvent dilution, ageing, ligands post synthetic treatment) in ambient atmosphere is investigated by means of a comprehensive morphological (electron microscopy), structural (θ/2θ X-ray diffraction (XRD) and grazing incidence wide angle scattering (GIWAXS)), and spectroscopic chemical (1H nuclear magnetic resonance (NMR), nuclear Overhauser effect spectroscopy (NOESY), absorption and emission spectroscopy) characterization. The aging and solvent dilution contribute to modify the nanocrystal morphology, due to a modification of the ligand dynamic. Moreover, we establish the ability of aliphatic carboxylic acids and alkyl amines ligands to induce, even in a post preparative process at room temperature, structural, morphological and spectroscopic variations. Upon post synthesis alkyl amine addition, in particular of oleyl amine and octyl amine, the highly green emitting CsPbBr3 nanocubes effectively turn into one-dimensional (1D) thin tetragonal nanowires or lead halide deficient rhombohedral zero-dimensional (0D) Cs4PbBr6 structures with a complete loss of fluorescence. The addition of an alkyl carboxylic acid, as oleic and nonanoic acid, produces the transformation of nanocubes into still emitting orthorombic two-dimensional (2D) nanoplates. The acid/base equilibrium between the native and added ligands, the adsorbed/free ligands dynamic in solution and the ligand solubility in non-polar solvent contribute to render CsPbBr3 particularly sensitive to environmental and processing conditions and, therefore prone to undergo to structural, morphological and, hence spectroscopic, transformations. [ABSTRACT FROM AUTHOR]

Anastasios John Kanellopoulos1,2 1LaserVision Clinical and Research Institute, Athens, Greece; 2Department of Ophthalmology, NYU Medical School, New York, NY, USA Purpose: To evaluate the safety, efficacy, and contralateral eye comparison of topography-guided myopic LASIK with two different refraction treatment strategies. Setting: Private clinical ophthalmology practice. Patients and methods: A total of 100 eyes (50 patients) in consecutive cases of myopic topography-guided LASIK procedures with the same refractive platform (FS200 femtosecond and EX500 excimer lasers) were randomized for treatment as follows: one eye with the standard clinical refraction (group A) and the contralateral eye with the topographic astigmatic power and axis (topography-modified treatment refraction; group B). All cases were evaluated pre- and post-operatively for the following parameters: refractive error, best corrected distance visual acuity (CDVA), uncorrected distance visual acuity (UDVA), topography (Placido-disk based) and tomography (Scheimpflug-image based), wavefront analysis, pupillometry, and contrast sensitivity. Follow-up visits were conducted for at least 12 months. Results: Mean refractive error was -5.5 D of myopia and -1.75 D of astigmatism. In group A versus group B, respectively, the average UDVA improved from 20/200 to 20/20 versus 20/16; post-operative CDVA was 20/20 and 20/13.5; 1 line of vision gained was 27.8% and 55.6%; and 2 lines of vision gained was 5.6% and 11.1%. In group A, 27.8% of eyes had over -0.50 diopters of residual refractive astigmatism, in comparison to 11.7% in group B (P

A COSMIC-1/FORMOSAT-3 (Constellation Observing System for Meteorology, Ionosphere, and Climate-1 and Formosa Satellite Mission 3) follow-on mission, COSMIC-2/FORMOSAT-7, had been successfully launched into low-inclination orbits on 25 June 2019. COSMIC-2 has a significantly increased Signal-to-Noise ratio (SNR) compared to other Radio Occultation (RO) missions. This study summarized the initial assessment of COSMIC-2 data quality conducted by the NOAA (National Oceanic and Atmospheric Administration) Center for Satellite Applications and Research (STAR). We use validated data from other RO missions to quantify the stability of COSMIC-2. In addition, we use the Vaisala RS41 radiosonde observations to assess the accuracy and uncertainty of the COSMIC-2 neutral atmospheric profiles. RS41 is currently the most accurate radiosonde observation system. The COSMIC-2 SNR ranges from 200 v/v to about 2800 v/v. To see if the high SNR COSMIC-2 signals lead to better retrieval results, we separate the COSMIC-2–RS41 comparisons into different SNR groups (i.e., 0–500 v/v group, 500–1000 v/v group, 1000–1500 v/v group, 1500–2000 v/v group, and >2000 v/v group). In general, the COSMIC-2 data quality in terms of stability, precision, accuracy, and uncertainty of the accuracy is very compatible with those from COSMIC-1. Results show that the mean COSMIC-2–RS41 water vapor difference from surface to 5 km altitude for each SNR groups are equal to −1.34 g/kg (0–500 v/v), −1.17 g/kg (500–1000 v/v), −1.33 g/kg (1000–1500 v/v), −0.93 g/kg (1500–2000 v/v), and −1.52 g/kg (>2000 v/v). Except for the >2000 v/v group, the high SNR measurements from COSMIC-2 seem to improve the mean water vapor difference for the higher SNR group slightly (especially for the 1500–2000 v/v group) comparing with those from lower SNR groups.

Abstract Chromia scale growth and Cr evaporation of ferritic stainless steel interconnects are known to be major causes of serious degradation of the solid oxide fuel cell (SOFC) stack. The development of suitable ceramic coating materials on the metallic interconnects has been demonstrated as an effective way to address these challenges. Herein, we developed a Mn 1.35 Co 1.35 Cu 0.2 Y 0.1 O 4 (MCCY) spinel material via a facile glycine-nitrate process as a protective coating on a metallic interconnect (SUS 441). Crystal structure and surface charge state analysis of the MCCY material revealed that co-doping of Y and Cu into the (Mn,Co) 3 O 4 spinel resulted in redistribution of the Mn ions (Mn3+ and Mn4+) into the octahedral site, which increased the electrical conduction by enhanced small polaron hopping. Accordingly, the MCCuY-coated interconnect exhibited ∼8 times lower area specific resistance (ASR) than that of the undoped Mn 1.5 Co 1.5 O 4 (MCO) coated interconnect. Moreover, time-dependent ASR behavior of MCCuY-coated sample was monitored in-situ using electrochemical impedance spectroscopy at 650 °C, showing excellent stability with no observable change for >1000 h, while the ASR of the MCO-coated sample was raised by ∼71%. After 1000 h operation, we found strong adhesion between the MCCuY coating and the metallic interconnect as well as remarkably restricted Cr diffusion into the coating layer. Furthermore, the parabolic constant associated with the oxidation kinetics of the MCCuY-coated substrate (8.25 × 10−11 mg2 cm−4 s−1) was ∼1 order of magnitude lower than that of the MCO-coated one (7.34× 10−10 mg2 cm−4 s−1) at 650 °C after 1000 h measurement. These results demonstrate that the MCCuY is a highly promising coating material of metallic interconnects for intermediate-temperature SOFC applications. Graphical abstract Image 1 Highlights • A MCCuY spinel material is developed as a metallic interconnect protective coating. • The MCCuY-coating exhibits ∼8 times lower ASR compared to the undoped MCO-coating. • The MCCuY-coated sample shows excellent stability without degradation for >1000 h. • The oxidation kinetics of the MCCuY-coating is ∼1 order lower than MCO-coating. [ABSTRACT FROM AUTHOR]

Abstract Employing additive to regulate the morphology of perovskite film is an effective method to enhance both the power conversion efficiency and long term stability of organic-inorganic hybrid perovskite solar cells. Here, we demonstrate that guanidinium thiocyanate (GuSCN) is a suitable additive for methylammonium lead iodide (MAPbI 3) perovskite materials. Addition of GuSCN into MAPbI 3 can simultaneously enhance the crystallinity, enlarge the crystal size, and reduce the trap density of the perovskite films. As a result, the MAPbI 3 perovskite with 10% GuSCN exhibits superior power conversion efficiency of 16.70% compared to the pristine MAPbI 3 perovskite solar cell (15.57%). At the same time, the MAPbI 3 perovskite solar cell with GuSCN additive shows better stability, power conversion efficiency retains ∼90% of its initial value compared to only ∼60% for pristine MAPbI 3 perovskite solar cells after being stored for 15 days without encapsulation. Highlights • Guanidinium thiocyanate is used as an additive in MAPbI 3 perovskite. • Enhanced crystallinity and enlarged crystal size is obtained. • Power conversion efficiency and stability are improved. [ABSTRACT FROM AUTHOR]

Abstract We are presenting the results of research and development of a new active quenching and gating electronics for single photon avalanche detector. The goal of this work was to improve a detector package for laser time transfer ground to space applications in terms of long term detection delay stability, detection delay reproducibility and minimal drifts. The first version of mentioned detector package is operational on board of GNSS navigation satellites. They are based on relatively small 25 μ m diameter chips. They do provide timing resolution of typically 125 ps and stability of the order of 10 ps. The presented control electronics provides timing resolution of 25 ps and sub-picosecond timing stability and drifts. The device is constructed on a basis of electronics components for which the space qualified equivalents are commercially available. The device construction, tests and results are presented in detail. Highlights • Single photon counter is optimized for sub-picosecond long term stability. • Detection delay stability is several orders of magnitude better than jitter. • Stable single photon counter is attractive for averaging experiments. [ABSTRACT FROM AUTHOR]

Abstract Recent progress in the development of water oxidation electrocatalysts has mainly focused on achieving high performance in a single measurement, while the importance of durability has not yet been deeply studied. Additionally, oxygen evolution reaction (OER) involves a phase transition from a liquid to a gas, and thus, the removal of the generated oxygen bubble is an important factor for improving the activity or maintaining the performance. In this study, 3D ordered nanoporous nickel electrode is synthesized with a thickness of 5 µm by using a templating method composed of proximity field nanopatterning (PnP) and electrodeposition followed by introduction of NiFe(OH) 2 on the nickel electrode to increase the OER activity. The unique nanopore array structure of the electrode has advantages of not only an enlarged active surface area but also the fast removal of oxygen bubbles by spatial confinement effect. Consequently, the NiFe-decorated 3D ordered nanoporous nickel electrode shows a highly efficient oxygen-evolving ability with a turnover frequency of 2.9 s−1 and an ultralong durability of 300 h. Graphical abstract An electrochemical water oxidation by NiFe(OH) 2 decorated 3D ordered nanoporous nickel electrode is described. We find that the regular arrangement of nanopores in the nickel electrode can not only enlarge the surface area of the nickel electrode but also improve the removal of oxygen bubbles, which lead to the highly efficient and ultrastable water splitting. fx1 Highlights • Ordered nanopore array structure of nickel electrode were fabricated. • Introduction of NiFe(OH) 2 to as-prepared electrode exhibited outstanding OER activity. • Bubbles formed at the electrode surface were removed efficiently. • 300 hrs of long-term durability was achieved. [ABSTRACT FROM AUTHOR]

The high fuel flexibility of solid oxide fuel cells allow them to be operated using carbonaceous fuels. This work focuses on a supply of carbon monoxide on large planar single cells, since detailed investigations thereof are rarely found in literature. In the course of this project, stable cell operation was achieved with CO / CO 2 / N 2 gas compositions at 800°C and 750°C as well as acceptable performance, though test results with H 2 / H 2 O / N 2 gas mixtures were not reached. Electrochemical impedance measurements revealed high polarization resistances to be the cause of this differences in performance. The combination of carbon monoxide and hydrogen as reactants in fuel mixtures results in rapid performance degradation: a performance reduction of 27% was recognizable within 6 h. Additionally, a 100 h test at 700°C with CO/CO 2 /N 2 = 20/10/70 vol% in polarization conditions (50 mA cm −2 ) is also presented, wherein there was continuous degradation at a rate of 17.2% over 100 h. Scanning electron investigations showed significant influences on the microstructure as carbon led to an enlargement of the nickel components and the coverage of the catalyst surfaces, respectively. [ABSTRACT FROM AUTHOR]

Pharmaceutical manufacturers have to study the stability of drug products before marketing according to ICH guideline Q1A(R2); data of those investigations aim to set expiry dates. The expiry date on the container of a remedy assures the physician and the patient a stability of the drug in its formulation i.e. within a specification of 95–105%. Only few studies show that shelf‐lives of pharmaceutical products are often longer than expiration dates. The objective of the study presented here was determining the content of nine expired ampoules manufactured in the last century and identifying the impurity profile by means of HPLC-UV and HPLC–MS, respectively. The ampoules are part of the “PEAK-collection” of long expired finished pharmaceutical products at IBMP, Nürnberg‐Heroldsberg, and consists among others of epinephrine (Suprarenin and Adrenalin in Oil), etilefrine (Effortil ® ), synephrine (Sympatol ® ), caffeine and procaine (Impletol), caffeine and sodium salicylate (Caffeinum Salicylicum), dipyridamole (Persantin ® ), furosemide (Lasix ® ), and metamizole (Novalgin ® ). For chromatographic investigations methods of the European Pharmacopoeia for related substances were used; for determining the content, they were validated for linearity, precision, and accuracy. The results were compared to current reference ampoules. Five out of nine ampoules were still within the specified content limits. In Suprarenin and Adrenalin in Oil, both containing epinephrine, Impletol (procaine), and Persantin ® (dipyridamole) contents were decreased to 70%, 74%, 79%, and 86%, respectively, and therefore out of specification. [ABSTRACT FROM AUTHOR]

The progress in developing the electrochemical sensors for biomolecule detection requires a facile device fabrication method. Herein, we report printing of silver (Ag) precursor and copper oxide nanoparticles (CuO NPs) inks by nozzle-jet technique to fabricate non-enzymatic glucose biosensor on flexible polyethylene terephthalate (PET) substrate. The fully printed CuO NPs/Ag/PET electrodes were characterized using electrochemical techniques for non-enzymatic biosensing of glucose. The fully printed non-enzymatic biosensor exhibited a high sensitivity (1424.2 μA mM −1  cm −2 ), linear range from 0.1 to 15 mM, low detection limit (0.3 μM; S/N = 3) and fast response time of ∼2 s under a working potential of +0.6 V. Additionally, printed electrodes demonstrated an excellent long term stability, high reproducibility, good selectivity and high accuracy during glucose concentration measurements in human blood and serum samples. These results indicate that the electrode fabrication using nozzle-jet printing can be regarded as a potential technique for the future development of high performance and low cost bio/chemical sensor devices. [ABSTRACT FROM AUTHOR]

In this report, the solubilization behaviour of a hydrophobic drug Clozapine (CLZ) in micellar suspensions of pluronics having different hydrophilic lipophilic balance (HLB) ratios viz. P84, F127 and F108 in the absence and presence of bile salt sodium deoxycholate (SDC) has been studied. UV–Vis spectroscopy has been exploited to determine the solubilization capacity of the investigated micellar systems in terms of drug loading efficiency, average number of drug molecules solubilized per micelle ( n s ), partition coefficient ( P ) and standard free energy of solubilization (∆ G ° ). The morphological and structural changes taking place in pluronics in different concentration regimes of SDC and with the addition of drug CLZ has been explored using dynamic light scattering (DLS) and small angle neutron scattering (SANS) measurements. The SANS results revealed that aggregation behaviour of pluronic-SDC mixed micelles gets improved in the presence of drug. The micropolarity measurements have been performed to shed light on the locus of solubilization of the drug in pure and mixed micellar systems. The compatibility between CLZ and drug carriers (pluronics and SDC) was confirmed using powder X-ray diffraction (PXRD) and Fourier transform infrared spectroscopy (FTIR) techniques. Among the investigated systems, P84-SDC mixed system was found to be highly efficient for CLZ loading. The long term stability data indicated that CLZ loaded P84-SDC mixed micellar formulation remained stable for 3 months at room temperature. Further, it was revealed that the CLZ loaded P84-SDC mixed micelles are converted into CLZ loaded pure P84 micelles at 30-fold dilutions which remain stable up to 48-fold dilutions. The results from the present studies suggest that P84-SDC mixed micelles can serve as suitable delivery vehicles for hydrophobic drug CLZ. [ABSTRACT FROM AUTHOR]

In this paper, high efficient and stable planar perovskite solar cells (PKSCs) have been designed and fabricated via employing high transparent Mg-doped ZnO films with excellent electron transport ability as a novel class of electron transport layers (ETLs). Due to the optimized band alignment by Mg doping, the photogenerated electron injection and charge extraction from the perovskite film to ETL have been facilitated effectively and the planar PKSC based on 2% Mg-doped ZnO and MAPbI 3 yields the maximum power conversion efficiency (PCE) of up to 16.74%. Meanwhile, a higher PCE of 17.85% through a phenyl C 60 butyric acid methyl ester (PCBM) interfacial layer between the 2% Mg-doped ZnO and perovksite layer has been achieved for the first time. Moreover, the PKSCs with 2% Mg-doped ZnO/PCBM composite ETLs also demonstrate outstanding long term device stability and up to 91% of original PCE of the PKSCs, which can be retained even after exposure in ambient conditions over three-months. [ABSTRACT FROM AUTHOR]

The use of solar energy in architecture becomes more and more attractive nowadays. It offers great benefits such as: fossil fuel reduction, less CO2 emission that labels the architectural goods as ecobuildings. Particularly, the use of solar thermal systems in building integration has a big potential. Façade solar thermal collectors show double benefits in new architectural goods: integrated functional elements that fit the architectural appearance very well and at the same time they use a high fraction of solar energy for thermal energy needs of the building. This is a sustainable way of use of solar energy and consequently decrease the CO2 impact to the environment. In this work, the new model of a façade windows-like collectors and their advantages are described. Namely, it is an ideal module to build-it in the south façade of the building; it could be residential, manufacturing or office building. With facade types of collectors, the architectural appearance of the buildings is not destroyed and at the same time the build-in elements are functional: they participate to a great portion of total energy needs of the building.

Preparation of high-quality and pure phase mixed-organic-cation FA 1-x MA x PbI 3 perovskite film is a big challenge, especially on a porous oxide scaffold for mesoscopic perovskite solar cells. In this study, we fabricated a pure phase of mixed-organic-cation perovskite FA 1-x MA x PbI 3 simply using a conventional two-step method. Effect of chemical composition and morphology on the photovoltaic performance and stability of the mixed-organic-cation perovskite has been studied in details. Results show that the FA 1-x MA x PbI 3 perovskite thin films with a FA + :MA + molar ratio of 0.7:0.3 demonstrate the best photovoltaic performance. Mesoscopic perovskite solar cells fabricated using these FA 0.7 MA 0.3 PbI 3 thin films yield a power conversion efficiency (PCE) up to 16.0%. Moreover, the devices present a superior stability and the unsealed devices exposed in ambient condition (25 °C, 50%–60% relative humidity) can maintain their photoelectric performance without apparent PCE loss for up to 20 days. [ABSTRACT FROM AUTHOR]

Ceria nanoparticle is a well-known fuel borne additive for reducing the particulate emissions from diesel engines. Main challenges in the use of ceria nanoparticles are the lack of long-term dispersion stability in diesel and their effect on lubricity of diesel. The present work mainly focuses on synthesis of stable ceria nanoparticle diesel suspension and study on their lubricity. Ceria nanoparticles were synthesized by co-precipitation method and nano fluids were prepared by two-step method. The optimum concentration of oleic acid (surfactant) was determined based on critical micelle concentration studies and concentration of ceria nanoparticle in diesel was varied from 5 to 25 ppm. Long term dispersion stability studies using Dynamic light scattering system and Turbidity meter shows 10 ppm as an optimum concentration of ceria nanoparticle in diesel for maximum stability. Tribological properties of modified diesel were studied by a standard pin on disk apparatus. The wear rate was found to be reduced for all the nano additive concentrations in diesel and was least for 15 ppm. Based on studies conducted, 10 ppm is reported as an optimum concentration of nanoparticle in diesel having both enhanced stability and lubricity as compared to other concentrations of ceria nanoparticles in diesel. [ABSTRACT FROM AUTHOR]

In this paper, we report on the stability of p-type passivated emitter and rear cells under ultraviolet (UV) exposure with various silicone nitride passivation coatings and embedded in different encapsulation polymers. Our results reveal that UV transparent polymers can result in a module power loss of up to 6% under a UV irradiation dose of 497 kWh/m2. We show that the degradation in power is caused by a reduction in open circuit voltage. This loss is related to an increased recombination in the cell, which we ascribe to a degradation of the surface passivation. With ray tracing simulations, we determine the number of photons reaching the passivation interface. Assuming that all photons with energies above 3.5 eV de-passivate the interface is in agreement with our experimental results. Copyright © 2017 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Finding efficient electrocatalyst for oxidation of small organic molecules such as methanol (CH 3 OH), formic acid (HCOOH), formaldehyde (HCHO) etc. is essential for the development of their respective direct fuel cells. We report here highly dispersed platinum nanoparticles (PtNPs) on carbon nitride (CN x ) were successfully synthesized by the ultrasound mediated sodium borohydride reduction of H 2 PtCl 6 in presence of CN x nanosheets. This platinum–carbon nitride (Pt/CN x ) composite exhibited superior electrocatalytic activity towards oxidation of CH 3 OH, HCOOH and HCHO in acid media. The mass activity, onset potential, tolerance to carbon monoxide (CO) poisoning and long term durability for the catalytic oxidation of CH 3 OH, HCOOH, HCHO on Pt/CN x catalyst in acid media is much higher than that of commercial Pt/C catalyst. The mass activity of Pt/CN x catalyst at ∼0.64 V (forward scan) is 310 mA/mg Pt which is 2.7 time higher than that of commercial Pt/C for methanol oxidation. The electrooxidation of HCOOH on Pt/CN x occurs via dual mechanism with greatly enhanced oxidation through dehydrogenation pathway in comparison with commercial Pt/C. The mass activity on Pt/CN x at 0.3 V (vs. NHE) is 25 times higher than that of Pt/C for oxidation of HCOOH. The superior catalytic activity and durability of this Pt/CN x catalyst can be attributed to high dispersion of PtNPs and strong catalyst support interaction. [ABSTRACT FROM AUTHOR]

In 1986 the roughness reference standards made of silicon were produced at the Laboratory for Precise Measurements of Length (LFSB), which is now a part of Croatian Metrology Institute (HMI) designated as HMI/FSB-LPMD. At that time, roughness standards were commonly made either from steel or glass. After 3 decades of use it was decided to conduct a research of metrological features on two silicon roughness standards which were continuously used as primary standards for roughness in Croatia. The analysis is based on measurement results of roughness parameters ( Ra , Rz and RSm ) from calibration certificates provided by several national metrology institutes. Statistical consistency is checked with Birge ratio test, and En values are calculated in order to check if significant change of roughness parameters over the years can be determined. [ABSTRACT FROM AUTHOR]

The science and technology of organic electronics have made consistent progress. However, the long-term stability of organic devices is a critical issue that remains to be resolved. Encapsulation is a straightforward and practical means to protect organic materials from oxygen or moisture and thus improve air stability. Here, we report a high-performance flexible inorganic SiN x /SiO x N y hybrid barrier film for application in organic solar cells (OSCs). This hybrid barrier film shows average transmittance of 85.5% and a water-vapor transmission rate of 7.1×10 –5 g m −2 day −1 . In OSCs comprising poly[4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-bA]dithiophene-2,6-diyl][3-fluoro-2-[(2-ethylhexyl)carbonyl] thieno[3,4-b]-thiophenediyl] (PTB7) and [6,6]-phenyl-C 70 -butyric acid methyl ester (PC 70 BM), which were encapsulated by the SiN x /SiO x N y hybrid barrier film, the power-conversion efficiency remained above 86% of the initial value even after 2000 h of storage in air, which is comparable to that obtained for a device encapsulated by a glass lid. [ABSTRACT FROM AUTHOR]

The assembly, structure, composition and sensing properties of novel bisdithiocarbamate based gold nanoparticle networks have been investigated. The sensing properties have been studied with vapors of toluene, 1-propanol, water, and 4-methyl-2-pentanone. We demonstrated that bisdithiocarbamates based chemiresistive sensors show sensing properties versus volatile organic compounds (VOC) comparable to thiol based composites but that they are superior in their long term stability.

Long-term stability is a major issue preventing dye-sensitized solar cells (DSCs) market implementation. The DSC stability problem relates to the sealing methods which usually employ thermoplastic sealants. This communication shows for the first time that laser glass sealing originates stable and efficient DSCs. Laser sealed DSCs showed remarkable stability compared to the Surlyn® sealed devices ( ca . 2% vs . 44%) after accelerated ageing during 1000 h, at 65 °C, light intensity of 765 W m −2 and resistive electrical load (~0.6 V). These results show that efficient encapsulation methods are crucial to DSC stability and that the developed sealing process can bring stable and efficient DSCs to the photovoltaic market. [ABSTRACT FROM AUTHOR]