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This article presents a model that can automatically produce a power amplifier's (PA) design parameters, that is, transmission lines (TLs) dimension, from a dataset of user‐specified design goals like gain, efficiency, linearity, and scattering (S‐) parameters. Based on the applied boundary conditions, a synthetic dataset is generated with the best range of design parameters (W and L). This dataset is utilized for training the physics‐informed neural network (PINN) model with user‐specified design goals as input and design parameters as target to produce the optimum value of W and L as the resultant output. Furthermore, utilizing the obtained dimensions, design, simulation, fabrication, and measurement of a PA are performed to validate our proposed model. The results of large signal measurements of PA are drain efficiency (DE) of 26.9%, power added efficiency (PAE) of 24.7%, output power (Pout) of 30.98 dBm at an input power Pin$$ \left({P}_{in}\right) $$ of 19 dBm, and gain of 12.41 dB at an operating frequency of 1.625 GHz. It has been observed that the design parameters produced by the model have a significant agreement with the validated output. Also, the statistical error analysis is done by calculating the error metrics between the validated output and the actual output of the PA design. [ABSTRACT FROM AUTHOR]

The manuscript presents an efficient method for the synthesis of various cis-azetidin-2-ones with high regio- and diastereoselectivity. This approach utilizes Kinugasa reaction involving diverse functionalized nitrones, including diaryl nitrones and α,β-unsaturated nitrones, in conjunction with acetylenic alcohols. Copper (I) serves as a catalyst to facilitate the transformation. [ABSTRACT FROM AUTHOR]

In this paper, behavioral modeling of a driver amplifier is implemented by using S2P and S2D model setup. By using the standard silicon-based driver amplifier for obtaining the measured results of Scattering (S)- parameters and large signal parameters for temperatures 25°C and 85°C. These parameters are imported into the S2P and S2D models to perform the small signal and large signal analysis at 3 GHz frequency for temperatures 25°C and 85°C. Then, the simulated results are compared with the measured results to verify the efficient utilization of behavioral models. The novelty of this work deals with the simulation study of the characteristics of a silicon-based driver amplifier, which are obtained directly from the measurements. This proposed method is essential for performing hetero-integration of transceiver design, which can be further utilized to improve the efficiency of transceiver for high-frequency band. At last, the study of relative error performance analysis between measured and simulated results of different parameters is carried out and calculated value of NMSE (in %) for S11, S12, S21, S22, gain, pout, 1 dB compression point, ACP, 3rd harmonics, 4th harmonics, and 5th harmonics are 0.0083, 0.0055, 0.0086, 0.011, 0.0844, 0.814, 0.926, 0.71, 0.22, 0.012 and 0.070 respectively. [ABSTRACT FROM AUTHOR]

The structural, electronic, and thermodynamical properties of Cn(N3)m (n = 1–7) (m = 4, 6) organic azides have been investigated using Density Functional Calculations. The ground state structures of organic azides were compared with CnHm (n = 1–7) (m = 4, 6) cumulenes which shows their higher relative stability. The stability and reactivity of organic azides were analyzed by calculating the HOMO‐LUMO gap, binding energies, and harmonic frequencies of the azides. The binding energy and formation energy of Cn(N3)m (n = 1–7) (m = 4, 6) organic azides suggest their energetic stability. The structural analysis of the azide group in Cn(N3)m (n = 1–7) (m = 4, 6) organic azide shows a tendency to stabilize at a maximum separation between functional azide groups. Ionization potential, electron affinities, and global hardness have been computed for Cn(N3)m (n = 1–7) (m = 4, 6) organic azides and the odd–even alternation rule was observed. The molecular dynamic simulation performed at 300 K for 1 fs confirms organic azide's structural stability at room temperature, except for C4(N3)4, and the members of their family can be synthesized. [ABSTRACT FROM AUTHOR]

The structural, electronic, and thermodynamical properties of Cn(N3)m (n = 1–7) (m = 4, 6) organic azides have been investigated using Density Functional Calculations. The ground state structures of organic azides were compared with CnHm (n = 1–7) (m = 4, 6) cumulenes which shows their higher relative stability. The stability and reactivity of organic azides were analyzed by calculating the HOMO‐LUMO gap, binding energies, and harmonic frequencies of the azides. The binding energy and formation energy of Cn(N3)m (n = 1–7) (m = 4, 6) organic azides suggest their energetic stability. The structural analysis of the azide group in Cn(N3)m (n = 1–7) (m = 4, 6) organic azide shows a tendency to stabilize at a maximum separation between functional azide groups. Ionization potential, electron affinities, and global hardness have been computed for Cn(N3)m (n = 1–7) (m = 4, 6) organic azides and the odd–even alternation rule was observed. The molecular dynamic simulation performed at 300 K for 1 fs confirms organic azide's structural stability at room temperature, except for C4(N3)4, and the members of their family can be synthesized. [ABSTRACT FROM AUTHOR]

A safer, greener, and more effective reaction methodology for the synthesis of dihydroquinazolinones (DHQs) has been developed. The deep eutectic solvent (DES) ZnCl2/urea employed in this study efficiently accelerated the cyclization of 2‐aminobenzamide with different aldehydes (aromatic and heteroaromatic) to afford the target scaffolds without the generation of any oxidized product. This method has exhibited remarkable advantages such as quick reaction time, mild reaction conditions, high yield (82%–98%), operational simplicity, and selectivity. The approach was observed to be tolerant to electron‐donating and electron‐withdrawing functional groups. Green metric parameters (AEf, OE, AE, RME, CE, etc.) determined further aided this greener chemical approach. [ABSTRACT FROM AUTHOR]

In this paper, a study on the effects of strategically implemented holes in a miniaturized wideband bandpass filter (BPF) utilizing interdigital folded coupled lines is presented. First, the BPF is designed to produce the passband by introducing a fold in the coupled lines. The passband is centered at 9.3 GHz (X‐band), catering to radar applications. Coupled lines connected to a modified U‐shaped transmission line comprise the filter's design configuration. The novelty of the design resides in incorporating drilled holes along the coupled lines, which generate perturbations and resonant effects, resulting in enhanced impedance variations and improved filter performance. With the aid of electromagnetic analysis and simulation software, the coupled lines, U‐shaped transmission lines, and drilled hole diameters are all optimized. Vector Network Analyzer performs all the measurements and draws the comparisons. An increment of 22.58% is seen in return loss as it increases from −24 to −32 dB, and the insertion loss shows an increase of 16.74%. The proposed filter has been subjected to analytical study, simulation, and implementation, which have confirmed its exceptional return loss, favorable insertion loss, and compact dimensions. The research results make a valuable contribution to the development of miniaturized wideband BPFs, specifically focusing on their use in radar systems. In such systems, the ability to accurately and efficiently filter signals is paramount. The design insights and performance improvements presented in this study have significant implications for broader applications in microwave engineering and communication systems. [ABSTRACT FROM AUTHOR]

The present methodology explored the effectiveness and versatility of deep eutectic solvent with ultrasonic energy as an eco-friendly protocol for the synthesis of bisthioglycolic acid derivatives. Bisthioglycolic moiety holds its role as a potent scaffold in sulfur-containing drugs. The presented strategy offers significant advantages such as green catalyst as well as solvent, excellent yield, short reaction time, and simple reaction workup. This methodology shows a wide range of substrate scope that contain both electron-donating as well as electron-withdrawing groups. [ABSTRACT FROM AUTHOR]

Here, we have reported a novel deep eutectic solvent (DES) with tremendous activity for the synthesis of dihydropyridines. DESs have played a trio role in the reaction. It acts as a green catalyst, solvent, and in-situ substrate in this chemical reaction. This method offers various advantages such as metal-free catalysis, green solvent, high yields of the products, and short reaction time. [ABSTRACT FROM AUTHOR]

The manuscript describes a synthetic route for the formation of 5‐(methylisoindole‐1,3‐dione) pyrimidinones by [4+2] cycloaddition reactions of functionalized 1,3‐diazabuta‐1,3‐dienes with 2‐(3‐Oxo‐allyl)‐isoindole‐1,3‐dione generated in situ from phthaloylalanine and tosyl chloride using triethylamine as a base. The functionalized 5‐(methylisoindole‐1,3‐dione) pyrimidinones were further explored in the deprotection of amines to afford a variety of 5‐methylamino pyrimidinones. The synthesis of such functionalized pyrimidinones is significant as they have a wide range of pharmacological profiles and are valuable as organic synthons. Mechanistic insights are also proposed for the given synthetic methodology. [ABSTRACT FROM AUTHOR]

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]

The functionalization of β-lactams at C-3 position are useful for the strategic improvement in both the dimensions, namely synthetic utility, as versatile intermediate in organic synthesis and biological potential of these heterocyclic systems. The present manuscript involved the π-facial selective synthesis β-lactam hybrids employing highly regioselective and diastereoselective Oxo-Diels-Alder reaction of diethyl ketomalonate with α-dienyl-β-lactam with stereocentres at its α- and β-positions. This protocol provided the cycloaddition of α- and β-stereocentric diene with symmetrical heterodienophiles forming biologically potent regioselective and diastereoselective α-lactams substituted pyrano bifunctional hybrids in good yields and β-facially selectivity. [ABSTRACT FROM AUTHOR]

An eco-friendly, easily achievable and efficient strategy has been explored to synthesize functionalized bisthioglycolic acids using a variety of aldehydes and thioglycolic acid. The employed protocol is solvent free and provides the desirable products in excellent yields (90–99%) with atom economy. Besides, cost effectiveness, short reaction times and milder reaction conditions are among other captivating benefits of the reported methodology. [ABSTRACT FROM AUTHOR]

Abstract InhA is an enoyl acyl carrier reductase that catalyzes the chemo-selective reduction of its 2-trans-enoyl-ACP substrate. The pharmacological effects of the frontline medications used in the treatment of tuberculosis are elicited by inhibiting the enzyme InhA, which disrupts the mycolic acid biosynthesis pathway. The present study involves development of ligand-based pharmacophore model, docking studies, generation of 3D-QSAR model, and molecular dynamic simulation studies of virtually screened putative InhA inhibitors. The best field-based 3D-QSAR model was validated using partial least-square regression (PLS) method with high regression coefficient for training set (R 2) = 0.9256 and test set (R 2) = 0.7542, cross-validated coefficient (r cv 2) = 0.72 and R 2 pred = 0.9764. Also, virtual screening yielded compounds 4, 25, 1, and 30 exhibiting appreciable interactions (docking scores −5.972, −3.819, −3.801, and −3.701, respectively with InhA synthetase; PDB ID: 1BVR). Further, ADMET studies supported drug-like potential of compounds 25, 1, and 30 whereas compound 4 showed negligible human oral absorption. The molecular dynamic simulation studies of the top scored molecule 25 suggested stability of 25-1BVR complex over the course of simulation run. Therefore, this work can be helpful for future discovery of novel InhA inhibitors against drug-resistant tuberculosis. [ABSTRACT FROM AUTHOR]

Abstract The reported work presents the diastereo, regio-, and π-facial selective synthesis of hetero-Diels-Alder (H-DA) cycloadducts with diazene derivatives viz. di-isopropyldiazocarboxylate and diethylazodicarboxylate with cis-/trans-3-butadienyl-β-lactams having stereocentres at its α and β-position. The H-DA reactions resulted in the formation of β-lactam tethered—3,6-dihydro-pyridazines in good yields. [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]