An efficient access to substituted tetrahydroquinolines, benzo[b]azepines, pyrido[3,2,1-jk]carbazoles, benzo[kl]acridines and pyrido[3,2,1-de]acridines in overall very good yields is described. The process involves Friedel–Crafts cyclizations of homo-and heterocyclic carboxylic acids 1a-e and alkanols 3a-e in the presence of AlCl3/CH3NO2 or TfOH (trifluoromethanesulfonic acid) or polyphosphoric acid (PPA) under suitable reaction conditions. Starting carboxylic acids 1a-e were obtained from their literature procedures. Our simple strategy offers easy access to polycyclic-fused systems in short reaction times and in moderate to good yields.

Keywords: Friedel-Crafts cycliacylations; alkanols; pyrido[3,2,1-jk]carbazole; Grignard reactions;
benzo[kl]acridine

In the present study, the structural properties, as well as the photodegradation performance of methylene blue (MB) and rhodamine B (Rh B) using hydrothermal synthesized Ag_xSn_1–xO₂ (0 ≤ x ≤ 1) nanocomposites were studied. The study was investigated using various techniques including EDS, XRD, FE-SEM, HR-TEM, photoluminescence spectroscopy, N₂ adsorption-desorption, GC-MS, and a double-beam spectrophotometer. The tetragonal SnO₂ phase dominates, while the cubic Ag₂O phase appears at larger x ratios (x ≥ 0.5). The crystallite and particle sizes were slightly raised for a low Ag ratio but dramatically increased for higher x ratios. Different morphologies emerge depending on the composition, such as spherical and irregular particles for x = 0 and 1, sheet-like morphology for x = 0.05, 0.2, and 0.4, and worm-like morphology for x = 0.5. The maximum surface area was calculated using the BET …

Facile and concise procedures for the construction of indole fused N-heterocyclic systems were described. A series of benzo-, pyrido-, thieno-, naphtho-fused azepinoindolones and indolo-azepinoquinolinones has been prepared starting from indol-2-acetic acids. The required starting carboxylic acids 3a–e were readily obtained by the N-arylations of indoleacetic acid 1 with various aromatic halides 2a–e. Subsequent carboxylic acids were esterified, followed by the addition of Grignard reagents to afford the corresponding indole-based alcohols 5a–e. The key step in this protocol is the Friedel–Crafts cyclisations of these precursors promoted by AlCl₃/CH₃NO₂ or trifluoromethanesulfonic acid (TfOH) or polyphosphoric acid (PPA) catalysts to form the desired condensed indoles in moderate to good yields.

L-Tyrosine (L-Tyr), an amino acid, has emerged as a potential biomarker for the detection and monitoring of liver cirrhosis (LC) and hepatocellular carcinoma (HCC). By analysing the serum levels of L-Tyr, healthcare pro­ fessionals can gain insights into the progression and development of these liver diseases. The utilization of L-Tyr as a biomarker holds potential for early detection and timely intervention, improving patient outcomes and treatment options. In this study we developed a novel nanocomposite based on eggshell waste and copper nanoparticles to modify carbon paste electrode (CPE) using chitosan gel as a binder for sensitive estimation of LTyr in human serum samples. The use of chitosan gel avoids the insulating effect of paraffin oil that was usually used for fabrication of CPE and enhance the sensitivity and selectivity of the modified electrode. Square wave voltammetry (SWV) was used to optimize the electrochemical parameters of the oxidation of L-Tyr onto the surface of the fabricated electrode (CuNPs@ESh/CS/CPE). The prepared composite was characterized using Xray diffraction (XRD), Fourier Transform - Infrared spectroscopy (FT-IR), UV–VIS spectroscopy and scan elec­ tron microscopy (SEM) and electrochemical impedence spectroscopy (EIS). The fabricated biosensor could es­ timate L-Tyr levels in controls, LC and HCC patients’ serum with high accuracy and sensitivity. The obtained results demonstrated the presence of significant difference in L-Tyr levels in the three studied groups. This in­ dicates that L-Tyr amino acid may serve as a crucial biomarker for the evaluation of such liver diseases.
 

The geomechanical properties of the Silah field were measured to identify the various types of rocks in the area and to determine the economically valuable zones with good petrophysical properties. A suite of well logging data was interpreted to delineate the subsurface lithostratigraphic units and permeable reservoirs across the two drilled wells. The estimated geomechanical parameters (compressional sonic velocity, shear sonic velocity, acoustic impedance, and Poisson's ratio) and certain petrophysical parameters (porosity and shale volume) were computed using empirical relations. This study aims to characterize and evaluate the sedimentary rock units of the field to delineate potential hydrocarbon reservoir formations based on their geomechanical and petrophysical properties. The well logging data interpretation and geomechanical properties analysis reveal that the subsurface lithostratigraphy comprises four types of lithology: sand, carbonate (limestone and dolomite), siltstone, and shale, interbedded. The main interesting reservoirs are in the Kharita, Bahariya, and Abu Roash (G and F members). The different constructed geomechanical crossplots indicate that the main lithology consists of shaley sandstone to sandstone and carbonates, with the shale type varying from predominantly laminated to partly dispersed. The results show that Larionov shale volume values (9.6% to 32%), total porosity ranged 10% to 26%, the compressional to shear wave velocity ratio (Vp/Vs) ranges from 1.58 to 1.912, and Poisson’s ratio values vary from 0.171 to 0.306. Also, the effective porosity ranges from 3.7%- 19.3%. There is a substantial bed of shale beneath and above these zones, which serves as a possible source and/or seal rock.

Manipulating unintentional doping in graphene layers, which is influenced by environmental factors and supporting substrates, is of significant concern for the performance and advancement of graphene-based devices. In this context, laser-induced tuning of charge carriers in graphene facilitates the exploration of graphene’s properties in relation to its surroundings and enables laser-assisted functionalization. This has the potential to advance optoelectronic devices that utilize graphene on transparent dielectric substrates, such as Al 2 O 3. In this work, laser power (P L) in Raman spectroscopy is used as a convenient contactless tool to manipulate and control unintentional carrier concentration and Fermi level position (E F) in graphene/α-Al 2 O 3 (G/Al 2 O 3) under ambient conditions. Samples are annealed at 400 C for two hours in an (Ar+ H 2) atmosphere to remove any chemical residues. Analysis of the peak …

The rapidly developing field of topological photonics has the potential to revolutionize the design and operation of optical systems. This study presents a novel approach for constructing a resilient sensor based on topological resonance. The coupling of the photonic crystal waveguide (PCW) with the topological corner state (TCS) within the structure forms the proposed sensor. The PCW provides a well-defined propagating mode, while the TCS is a localized mode that is topologically protected against perturbations. The coupling between the two modes contributes growth to a Fano resonance and results in a sharp and narrow spectral feature sensitive to the refractive index variation of the surrounding medium. The proposed sensor possesses a high sensitivity of ∼461.96 nm/RIU with a high Q-factor \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts …

Abstract Herein, the anodization of 2.6 μm Al-0.2 at.% Cu (Al-0.2 Cu) films on TiN/p-type Si substrate were performed using common acidic mediums at different ranges of anodization voltage (V a) to produce porous anodic alumina (PAA) nanostructures with high porosity. The anodization of Al-0.2 Cu in 1 M H 2 SO 4 at V a range of 10–30 V produced a higher oxide thickness, and hence, a higher volume expansion factor, compared to the anodization in 0.75 M H 3 PO 4 at V a range of 100–140 V. The increase in V a, as expected, increases the inter-pore distance, pore size, and porosity of the PAA and improves the anodization rate. The optical sensing performance of the synthesized PAA under different conditions was investigated. The maximum surface wettability was attained for PAA anodized in 1 M H 2 SO 4 at 20 and 30 V. Moreover, the Vickers hardness (HV) of PAA was improved by forming a thin alumina …