Nanostructured bismuth ferrite nanoparticles: synthesis, characterization, electrical/magnetic properties and photocatalytic performance.

Nanostructured bismuth ferrite (BiFeO) single-phase nanoparticles with 76.2% crystallinity and 100% perovskite structure were synthesized using a co-precipitation method. The X-ray diffraction pattern confirmed the perovskite structure of BFO, and Rietveld refinement demonstrated the presence of a triclinic structure with the 1 space group.

An advanced deep learning predictive model for air quality index forecasting with remote satellite-derived hydro-climatological variables.

Forecasting the air quality index (AQI) is a critical and pressing challenge for developing nations worldwide. With air pollution emerging as a significant threat to the environment, this study considers seven study sites of the sub-tropical region in Bangladesh and introduces a novel hybrid deep-learning model. The proposed model, expressed as CLSTM-BiGRU, integrates a convolutional neural network (CNN), a long-short term memory (LSTM), and a bi-directional gated recurrent unit (BiGRU) network.

The medicinal activity of lyophilized aqueous seed extract of Lepidium sativum L. in an androgenic alopecia model.

This study evaluated the topical effect of Lepidium sativum lyophilized seed extract (LSLE) towards Sustanon-induced alopecia in male adult Wistar albino rats in vivo, compared to minoxidil topical reference standard drug (MRD). LC-MS/MS together with molecular networking was used to profile the metabolites of LSLE. LSLE treated group revealed significant changes in alopecia related biomarkers, perturbation of androgenic markers; decline in testosterone level and elevation in 5α-reductase (5-AR); decline in the cholesterol level.

Rate of upper incisor retraction in Class II division 1 patients managed with palatal versus buccal miniscrew supported segmental orthodontics: Randomized parallel clinical trial.

Objective: This study was conducted to compare maxillary incisor retraction rates using buccal orthodontics with segmented arch approach supported by a buccal or palatal mini-screw in non-growing Class II Division 1 patients during a 3-month period.

Patients And Methods: All patients between September 2018 and December 2021 with following criteria were included: non-growing class II division 1 protrusion, indication for premolar extraction, no or little crowding, normal overbite, no previous orthodontic treatment, no systematic disease, good oral hygiene, no periodontal problems or oral habits. Mini-implant was inserted buccally or palatally between upper second premolar and first molar bilaterally.

Development of Semisynthetic Apoptosis-Inducing Agents Based on Natural Phenolic Acids Scaffold: Design, Synthesis and In-Vitro Biological Evaluation.

A crucial target in drug research is magnifying efficacy and decreasing toxicity. Therefore, using natural active constituents as precursors will enhance both safety and biological activities. Despite having many pharmacological activities, caffeic and ferulic acids showed limited clinical usage due to their poor bioavailability and fast elimination.

Optimization algorithms as training approach with hybrid deep learning methods to develop an ultraviolet index forecasting model.

The solar ultraviolet index (UVI) is a key public health indicator to mitigate the ultraviolet-exposure related diseases. This study aimed to develop and compare the performances of different hybridised deep learning approaches with a convolutional neural network and long short-term memory referred to as CLSTM to forecast the daily UVI of Perth station, Western Australia. A complete ensemble empirical mode decomposition with adaptive noise (CEEMDAN) is incorporated coupled with four feature selection algorithms (i.

Dual-Function, Tunable, Nitrogen-Doped Carbon for High-Performance Li Metal-Sulfur Full Cell.

Lithium metal-sulfur (Li-S) batteries are attracting broad interest because of their high capacity. However, the batteries experience the polysulfide shuttle effect in cathode and dendrite growth in the Li metal anode. Herein, a bifunctional and tunable mesoporous carbon sphere (MCS) that simultaneously boosts the performance of the sulfur cathode and the Li anode is designed.

Metallic MoS for High Performance Energy Storage and Energy Conversion.

Metallic phase 2D molybdenum disulfide (MoS ) is an emerging class of materials with remarkably higher electrical conductivity and catalytic activities. The goal of this study is to review the atomic structures and electrochemistry of metallic MoS , which is essential for a wide range of existing and new enabling technologies. The scope of this paper ranges from the atomic structure, band structure, electrical and optical properties to fabrication methods, and major emerging applications in electrochemical energy storage and energy conversion.

Stable Metal Anode enabled by Porous Lithium Foam with Superior Ion Accessibility.

Lithium (Li) metal anodes have attracted much interest recently for high-energy battery applications. However, low coulombic efficiency, infinite volume change, and severe dendrite formation limit their reliable implementation over a wide range. Here, an outstanding stability for a Li metal anode is revealed by designing a highly porous and hollow Li foam.

Unravelling the correlated electronic and optical properties of BaTaO2N with perovskite-type structure as a potential candidate for solar energy conversion.

We report on the first principles calculation of the electronic, structural and optical properties of BaTaO2N, using density functional theory (DFT) and finite difference time domain (FDTD) methods. Band structure calculations were performed to calculate the direct and indirect bandgaps of the material. Density of states and Mulliken charge analysis as well as the electronic contour maps were established to determine the type of bonding and hybridization between the various electronic states.

Layered tantalum oxynitride nanorod array carpets for efficient photoelectrochemical conversion of solar energy: experimental and DFT insights.

Anodically fabricated tantalum oxide (Ta2O5) nanorod array carpets are converted into the corresponding tantalum oxynitride (TaON) through nitridation in an ammonia atmosphere. The measured optical bandgap energy of TaON is ∼2.3 eV, which is also confirmed via the density functional theory calculations.

Dento-skeletal effects of the Pendulum Hygienic Distalizer.

Objectives: To evaluate dento-skeletal effects of the Pendulum Hygienic Distalizer (P.H.D), utilized on expansion of the maxillary arch and distalizing of maxillary first molars.

Toxicity of binary chemical munition destruction products: methylphosphonic acid, methylphosphinic acid, 2-diisopropylaminoethanol, DF neutralent, and QL neutralent.

This paper reports the toxicity and environmental impact of neutralents produced from the hydrolysis of binary chemical agent precursor chemicals DF (methylphosphonic difluoride) and QL (2-[bis(1-methylethyl)amino]ethyl ethyl methylphosphonite). Following a literature review of the neutralent mixtures and constituents, basic toxicity tests were conducted to fill data gaps, including acute oral and dermal median lethal dose assays, the Ames mutagenicity test, and ecotoxicity tests. For methylphosphonic acid (MPA), a major constituent of DF neutralent, the acute oral LD(50) in the Sprague-Dawley rat was measured at 1888 mg/kg, and the Ames test using typical tester strains of Salmonella typhimurium and Escherichia coli was negative.

Development of a new dimeric cyclophane ligand: application to enhanced diastereo- and enantioselectivity in the catalytic synthesis of beta-lactams.

We detail the synthesis of a new C(2)-symmetric bis(cyclophane) ligand system that can be thought of as electronically analogous to binol, but which possesses the added "third dimension" of cyclophane chirality. The ligand synthesis involves a spontaneous (but unexpected) atropisomerization to the desired product. We have employed this ligand to form a metal complex that is an effective cocatalyst for the highly enantio- and diastereoselective catalytic asymmetric synthesis of a beta-lactam.

Catalytic, asymmetric alpha-chlorination of acid halides.

We present a full account of a tandem catalytic, asymmetric chlorination/esterification process that produces highly optically enriched alpha-chloroesters from inexpensive, commercially available acid halides using cinchona alkaloid derivatives as catalysts and polychlorinated quinones as halogenating agents. We have performed kinetics and control experiments to investigate the reaction mechanism and establish conditions under which the reactions can be best performed. We have developed NaH and NaHCO3 shuttle base systems as the easiest and most cost-effective ways of conducting the reactions, rendering the methodology economically competitive with known chiral halogenation procedures.

A multistage, one-pot procedure mediated by a single catalyst: a new approach to the catalytic asymmetric synthesis of beta-amino acids.

A catalytic asymmetric procedure for the preparation of beta-amino acids (specifically beta-substituted aspartic acid derivatives) is reported. The cinchona alkaloid catalyst benzoylquinine (BQ) mediates up to five distinct steps of a reaction pathway, all in one reaction vessel. The products of this reaction, highly optically enriched beta-substituted aspartic acid derivatives, were prepared from N-acyl-alpha-chloroglycine esters and acid chlorides in the presence of the catalyst.

Alpha-imino esters: versatile substrates for the catalytic, asymmetric synthesis of alpha- and beta-amino acids and beta-lactams.

The catalytic asymmetric addition of organic nucleophiles to alpha-imino esters has emerged as one of the most promising and intensely investigated routes to optically enriched alpha- and beta-amino acid derivatives and beta-lactams. The importance of alpha-imino esters stems not only from the vast appeal of the potential product classes,(1) but also from their remarkable reactivity as highly electrophilic imines. With each passing year, the number of publications concerning the asymmetric alkylation of imino esters grows significantly.

Sequential column asymmetric catalysis.

Since the introduction of catalysts and reagents on solid-support, researchers have developed new reaction systems to take advantage of their insoluble nature by designing multistep reaction sequences, high-throughput purification techniques, and combinatorial synthesis methods. The continuous flow system is one of these advancements and represents the foundation of a new technique termed sequential column asymmetric catalysis (CAC). In this strategy, reagents and catalysts are attached to a solid-phase support and loaded onto sequentially-linked columns.

The development of the first catalyzed reaction of ketenes and imines: catalytic, asymmetric synthesis of beta-lactams.

We report practical methodology for the catalytic, asymmetric synthesis of beta-lactams resulting from the development of a catalyzed reaction of ketenes (or their derived zwitterionic enolates) and imines. The products of these asymmetric reactions can serve as precursors to a number of enzyme inhibitors and drug candidates as well as valuable synthetic intermediates. We present a detailed study of the mechanism of the beta-lactam forming reaction with proton sponge as the stoichiometric base, including kinetics and isotopic labeling studies.

Bifunctional asymmetric catalysis: a tandem nucleophile/Lewis acid promoted synthesis of beta-lactams.

[reaction: see text]. We describe a superior procedure for the catalytic, asymmetric synthesis of beta-lactams using a bifunctional catalyst system consisting of a chiral nucleophile and an achiral Lewis acid.

Generation of ketenes from acid chlorides using NaH/crown ether shuttle-deprotonation for use in asymmetric catalysis.

[reaction: see text] We describe methodology for the in situ generation of reactive monosubstituted ketenes from acid chlorides through a shuttle deprotonation process using NaH as an inexpensive stoichiometric base and a crown ether cocatalyst. We have successfully applied this new procedure to the catalytic, asymmetric synthesis of beta-lactams and alpha-haloesters.

A catalyst that plays multiple roles: asymmetric synthesis of beta-substituted aspartic acid derivatives through a four-stage, one-pot procedure.

We report a new method for the catalytic, asymmetric synthesis of beta-substituted aspartic acid derivatives in which the nucleophilic catalyst serves up to four discrete roles in a one-pot procedure: catalytic dehydrohalogenation of acid chlorides to form ketenes; catalytic dehydrohalogenation of alpha-chloroamines to form the corresponding imines; catalyzed [2 + 2]-cycloaddition to produce intermediate acyl beta-lactams; and finally, nucleophilic ring opening to afford optically enriched beta-substituted aspartic acids in high enantioselectivity and diastereoselectivity.