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Rocks contain a large number of elements such as Na, K, Ca, Mg, Fe, Mn, and Ti. The determination of those element contents is important in geological and geographical exploration as well as the original identification and classification of rocks. Currently, the analysis of the elemental composition of rocks can be carried out on equipments such as ICP-OES, ICP-MS,... However, in some laboratories with limited conditions, the analysis has many difficulties. In the present study, we analyzed rock samples after being treated by microwave using flame atomic and molecular absorption spectroscopy. The results showed that the content of elements in the range of Na (0.31 – 2.46%), K (1.38 – 3.71%), Ca (0.08 – 0.23%), Mg (0.16 – 0.69%), Fe (2.38 – 5.19) %), Mn(0.08 – 0.1%) and Ti(0.12 – 0.36%). The study provides a simple and cost-effective method for rock analysis.

The study focused on reviewing modern and effective drying methods assisted by infrared radiation, microwave and radio frequency. In which, the drying results of previous studies were reviewed to clarify the drying efficiency of drying methods with the support of infrared radiation, microwave and radio frequency. The review results showed that the radiant heating mechanism of infrared radiation and the volumetric heating mechanism of microwave and radio frequency supported the process of material heating and moisture diffusion within the material. As a result, the drying process achieved high drying efficiency, the drying time was significantly shortened and the quality of the dried products was improved both in terms of sensory quality and nutritional quality. The study of the application of infrared radiation, microwave and radio frequency in drying technique had a high scientific, technological and practical significance. This would be the foundation for finding suitable drying methods and drying modes to improve drying efficiency as well as the quality of dried products.

BACKGROUND AND AIMS The hepatic venous pressure gradient (HVPG) is the standard for estimating portal pressure but requires expertise for interpretation. We hypothesized that HVPG could be extrapolated from liver histology using a machine learning (ML) algorithm. APPROACH AND RESULTS Patients with NASH with compensated cirrhosis from a phase 2b trial were included. HVPG and biopsies from baseline and weeks 48 and 96 were reviewed centrally, and biopsies evaluated with a convolutional neural network (PathAI, Boston, MA). Using trichrome-stained biopsies in the training set (n = 130), an ML model was developed to recognize fibrosis patterns associated with HVPG, and the resultant ML HVPG score was validated in a held-out test set (n = 88). Associations between the ML HVPG score with measured HVPG and liver-related events, and performance of the ML HVPG score for clinically significant portal hypertension (CSPH) (HVPG ≥ 10 mm Hg), were determined. The ML-HVPG score was more strongly correlated with HVPG than hepatic collagen by morphometry (ρ = 0.47 vs. ρ = 0.28; P

This study focused on the experimental drying of Bo Chinh ginseng by the ultrasound-assisted heat pump drying method, in which the effects of drying air temperature (T), ultrasonic power (P), intermittency ratio of ultrasound generator (A) on the moisture effective diffusion coefficient (Deff), saponin content (Sp) and color change (dE) during the drying process were determined. The results showed that the drying time was reduced from 12.5 h at 35 °C to 8.9 h at 40 °C and greatly reduced to 5.8 h at 55 °C. The moisture diffusion coefficient Deff and color change index increased with the increase in drying temperature. Meanwhile, from 35 °C to 45 °C, the saponin content after drying tended to increase gradually, but when the temperature continued to rise from 45 °C to 55 °C, the saponin content decreased. The effect of ultrasonic power in the drying process was in particular as follows. The drying time of 8.8 h at 40 W ultrasonic power reduced to 7.8 h at 80 W ultrasonic power, and reduced to 7 h at 160 W ultrasonic power. The remaining saponin content after drying tended to increase gradually at the power level of 40–120 W (from 89.2% to 95.2%) and decrease when the power increased from 120 to 160 W (from 95.2% to 90.5%). The moisture diffusion coefficient Deff also increased with the increase in ultrasonic power. Meanwhile, the color change of dried products decreased as the ultrasonic power increased in the range of 40–120 W but increased with the ultrasonic power range from 120 to 160 W. Additionally, the experimental method and Box–Behnken design were used for optimizing the drying process with the optimal drying conditions such as drying air temperature of 45.2 °C, ultrasonic power of 127.7 W and intermittency ratio of ultrasound generator of 0.18.

This paper explores the role of school quality in immigrants’ home countries on their earnings in Germany, using native Germans as a benchmark. We propose an empirical analysis that highlights two important insights. First, there is a substantial gap in the returns to education between natives and immigrants in Germany, especially when we consider the quality of schooling in the source country where education was obtained. In particular, lower school quality reduces the endowment advantage that immigrants possess from their education. Second, quality-adjusted education helps us to better understand the potential driving force behind the native–immigrant wage gap. We show that this measure accounts for a substantial fraction of the unexplained part in the Oaxaca–Blinder decomposition. These findings emphasize the role of the school quality in explaining the imperfect transferability of human capital of immigrants in Germany.

This article presents a systematic empirical modeling approach in fully depleted silicon-on-insulator (FDSOI) CMOS for large-signal simulation in power amplifier applications. The model is constructed from multibias S-parameter measurements up to 67 GHz. The frequency dispersions in transconductance and output conductance are addressed by two independent radio frequency (RF) current sources. Angelov’s current formula is modified to adapt to the FDSOI transistors. Load-pull measurements are performed for the large-signal verification in a non-50- $\Omega $ environment. The model accurately predicts the nonlinear characteristics of the device under test and the harmonic components. The time-domain waveforms also show excellent agreement to the simulation.

The main purpose of this study was to select the appropriate ultrasound parameters that support the freezing process of Bo Chinh ginseng. This process involves placing Bo Chinh ginseng in an open-air environment and ensuring that the transducer does not come into contact with the material. The research results show that the ultrasound power, ultrasound irradiation temperature and intermittency ratio all affect the freezing time, nucleation temperature, color and microstructure of the materials. When the ultrasound continuously operated during the freezing process, at a frequency of 20 kHz, there was a 29.1% reduction in the freezing time at a power level of 100 W as compared to freezing without the help of ultrasound irradiation. The irradiation temperature and nucleation temperature have a linear relationship (y=−0.35x−0.93) which can help to control the nucleation temperature, thereby changing the ice crystal size. Ultrasound-assisted freezing at a 0.6 intermittency ratio had the shortest freezing time. The microstructure of the material changed after ultrasound-assisted freezing and many microchannels and holes were generated. When frozen at a wave rate of 0.4, the microchannels that were created in the material effectively supported the process of water drainage in the drying sublimation stage. At the same time, ultrasound irradiation did not affect the color of the post-freezing material when compared to the color of the frozen material that did not undergo ultrasound irradiation.

A microwave characterization at UHF band of a ferroelectric hafnium zirconium oxide metal-ferroelectric-metal (MFM) capacitors for varactor applications has been performed. By using an impedance reflectivity method, a complex dielectric permittivity was obtained at frequencies up to 500 MHz. Ferroelectric Hf0.5Zr0.5O2 of 10 nm thickness has demonstrated a stable permittivity switching in the whole frequency range. A constant increase of the calculated dielectric loss is observed, which is shown to be an effect of electric field distribution on highly resistive titanium nitride (TiN) thin film electrodes. The C-V characteristics of a “butterfly” shape was also extracted, where the varactors exhibited a reduction of capacitance tunability from 18.6% at 10 MHz to 15.4% at 500 MHz.

Osmotic membrane bioreactors (OsMBRs) are a recent breakthrough technology designed to treat wastewater. Nevertheless, their application in high-salinity wastewater treatment is not widespread because of the effects of saline conditions on microbial community activity. In response, this study developed an integrated sponge biocarrier-OsMBR system using highly salt-tolerant microorganisms for treating saline wastewater. Results showed that the sponge biocarrier-OsMBR obtained an average water flux of 2 L/m 2 h during a 92-day operation when 1 M MgCl 2 was used as the draw solution. The efficiency in removing dissolved organic compounds from the proposed system was more than 99%, and nutrient rejection was close to 100%, indicating excellent performance in simultaneous nitrification and denitrification processes in the biofilm layer on the carriers. Moreover, salt-tolerant microorganisms in the sponge biocarrier-OsMBR system worked efficiently in salt concentrations of 2.4%. A polytetrafluoroethylene MD membrane (pores = 0.45 μm) served to regenerate the diluted draw solution in the closed-loop system and produce high-quality water. The moving sponge biocarrier-OsMBR/MD hybrid system demonstrated its potential to treat salinity wastewater treatment, with 100% nutrient removal and 99.9% conductivity rejection.

Die Weiterbildung von Beschäftigten gewinnt durch die digitale Entwicklung, demografische Veränderungen sowie die zunehmende internationale Verflechtung immer mehr an Bedeutung. Dies gilt auch für Menschen mit Migrationshintergrund. Fast ein Drittel der deutschen abhängig Erwerbstätigen ohne Migrationshintergrund nahm von 2013 bis 2015 an mindestens einer beruflichen Weiterbildung teil. Bei den selbst Eingewanderten (1. Generation) sind dies 20 Prozent. In Deutschland geborene Beschäftigte mit mindestens einem eingewanderten Elternteil (2. Generation) bilden sich ähnlich häufig weiter wie Deutsche ohne Migrationshintergrund. Die höchste Teilnahmequote an Weiterbildung weisen mit 35 Prozent die abhängig erwerbstätigen Frauen der 2. Generation auf. Sie sind meist gut qualifiziert und arbeiten oft in qualifizierten Angestelltenpositionen sowie in weiterbildungsintensiven Branchen wie dem Erziehungs- und Gesundheitsbereich und der Öffentlichen Verwaltung. Solche Faktoren begünstigen die Teilhabe an Weiterbildung. Anstrengungen, um die Teilhabe an Weiterbildung zu erhöhen, sollten sich vor allem auf die selbst Eingewanderten der 1. Generation beziehen. Bedeutsam sind für diesen Personenkreis aber auch Ausbildung oder Studium sowie die Anerkennung mitgebrachter beruflicher Qualifikationen.

TiO2 nanocrystal doped with Cu has been fabricated by wet chemical processing. The obtained results of x-ray diffraction, optical absorption in the UV–Vis bands and luminescence spectra have shown that Cu has substituted Ti in the structure of TiO2 anatase phase when the Cu concentration is about 8 at%. In the case of larger Cu concentrations the copper oxide appeared and increased with increasing Cu concentration. The samples doped with Cu strongly absorb the visible light (400–900 nm) and their absorption edge shifts to the longer wavelength in dependence on the Cu concentration. The absorption in the visible light band is attributed to transitions between the impurities levels of Cu created in the energy band gap of TiO2. In addition, an absorption shoulder above 800 nm is observed and supposed to be related with the absorption of CuO. The experimental results prove that the TiO2 anatase doped with Cu is suitable for hydrogen generation by photocatalytic water splitting under sunlight.