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In this article, a study of performing machine learning (ML) based modeling for semiconductor devices has been developed using experimental microwave data. Characterization of gallium arsenide (GaAs) pseudomorphic high electron mobility transistors (pHEMTs) with different gate widths is used as the illustrative example to demonstrate the accuracy and effectiveness of the presented modeling procedure. The tested devices are based on the multifinger layout, in which the total gate width (W) is obtained by multiplying the number of fingers (Nf) and their length (W0). Machines are trained with scattering (S‐)parameter measurements up to 65 GHz by using the extreme gradient boosting (XGBoost) algorithm with K‐fold cross‐validation. Then, the output of the trained machine is utilized by the parameters such as Nf and W0 inside the Auto‐encoder (AE) model. In particular, the ML model with AE has a maximum of 99.88% prediction accuracy, despite the uncertainty inherent in the microwave measurements and the unavoidable deviations from the ideal behavior of the analyzed devices. [ABSTRACT FROM AUTHOR]

A green, sustainable, and efficient one-pot, synthetic strategy for the synthesis of 2,3-dihydroquinazolin-4(1H)-ones (DHQs) was developed. The ZnCl2/urea used as a deep eutectic solvent (DES) not only efficiently promoted the condensation between isatoic anhydride and benzaldehyde but unexpectedly acted as a nitrogen source (like ammonia) in situ to afford DHQs in excellent yields. This approach offers remarkable advantages, involving the triple role of DES in the synthesis of DHQs, atom-economical, green organocatalysts, metal-free conditions, cost-effectiveness, and tolerance to a range of functional groups. [ABSTRACT FROM AUTHOR]

Herein, we have designed and synthesized pyrimidinone-based dual chemosensor ( DPPA ) containing picolylamine moiety as binding unit. Investigation on the optical property of DPPA revealed fluorescence enhancement at 435 nm with Zn 2+ ion through binding with picolylamine and carbonyl moieties, while Cu 2+ ion was detected through fluorescence quenching at 425 nm and colorimetric changes at 350 nm due to complexation with picolylamine and deprotonation of amide NH group. The detection limit of Zn 2+ and Cu 2+ was calculated to be 10.04 nM and 34.1 nM, respectively. The Job’s plot showed formation of 1:2 and 2:1 binding stoichiometry of DPPA with Cu 2+ and Zn 2+ , respectively. 1 H NMR titration in CD 3 CN revealed downfield shift in methyl groups of N(CH 3 ) 2 and methylene ( CH 2 ) protons of picolylamine chain due to formation of coordinate bonds between Cu 2+ and DPPA , whereas only downfield shift of methylene ( CH 2 ) protons of picolylamine were responsible for complexation with Zn 2+ ions. The complexation mechanisms of DPPA with Cu 2+ and Zn 2+ were also supported by detailed theoretical calculations. [ABSTRACT FROM AUTHOR]