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Research has shown that the use of practical examples in undergraduate education promotes the retention of historically underrepresented students in STEM majors and lowers achievement gaps within courses. Since many students of color and women aspire toward careers in healthcare and the pharmaceutical industry, efforts to incorporate medicinal chemistry into the organic chemistry and advanced chemistry lab curriculum could potentially help enhance diversity and retention. There is currently a dearth of laboratory experiments that are medically relevant and technically accessible for incorporation into the undergraduate organic chemistry lab curriculum. The theoretical framework for optimization of drug leads and design of chemical libraries used in the exploration of structure-activity relationships is typically introduced in senior-level courses without hands-on laboratory training. In response to this, we have designed a laboratory experiment that translates the typical medicinal chemistry synthesis of a chemical analogue library into a method that can readily be deployed within an undergraduate laboratory setting through the synthesis of the clinically important antihypertensive drug prazosin and its analogues. By the use of commercially available starting materials, a small library of prazosin analogues can be synthesized utilizing nucleophilic aromatic substitution and amide-bond-forming condensation reactions. The experiment introduces a variety of concepts, including (1) retrosynthetic analysis in the design of chemical libraries, (2) methods in extraction and purification, and (3) instrumental analyses via [superscript 1]H and [superscript 13]CNMR spectroscopy, mass spectrometry, and melting point determination.

Bimetallic nanostructures can exhibit significant broadening of Mie resonances compared to monometallic nanoparticles. Here, we study these materials using Electron Energy Loss Spectroscopy at a single particle level. This technique is immensely effective to probe direct structure-property correlation of nanoparticles. We are thus able to confirm the broadening of Mie resonances at a single particle level. This effect is analyzed in the context of emergence of a new dielectric constant that originates from metallic interfaces. We employ Coronado-Schatz corrections to the usual dielectric constants of the constituent metals to quantitatively simulate these materials. The resultant materials thus exhibit optical cross-sections that are 38.5 % and 4.2 % of the gold and silver nanoparticle optical cross-section at 2.5 eV and 3.45 eV, respectively. A strong agreement between theory and experiment is observed. We also confirmed the effectiveness of our approach for nanoparticles with different morphologies as well as different compositional ratios. Our study suggests an effective strategy to regulate the dielectric properties of bimetallic nanostructures through interface engineering.

Abstract The present work describes the effect of structural modification of carbazole‐based photosensitizers carrying carboxylic acid as a common anchoring functionality, on the photovoltaic parameters of newly fabricated DSSCs. In this study, we have selected our previously reported three carbazole‐based derivatives, viz. S1‐3 having different structural designs, that is, D‐π‐A (S1), D‐D‐π‐A (S2), and A‐π‐D‐π‐A (S3) with different donor units and π‐spacers, but an identical cyanoacetic acid anchoring unit. We have evaluated their optical, electrochemical, and photovoltaic behaviors in order to explore their structure‐property relationships. Also, the theoretical investigations were performed to obtain a deeper understanding of their HOMO‐LUMO levels, charge distribution in FMOs, directional flow of electrons within the push‐pull type sensitizers, and optical behavior. Finally, the DSSCs were constructed by employing these dyes as sensitizers without any co‐absorbents and the performance of the devices was evaluated by using illuminated current‐voltage characteristics. Among the tested dyes, di‐anchoring S3 exhibited improved PCE of 3.77 % due to its strong adsorption on the TiO2 surface that resulted in superior VOC of the cell. While the S2 containing electron‐releasing anisole as an auxiliary donor exhibited better JSC value leading to the optimum PCE of 3.73 % which is comparable to that of S3. Obviously, these results validate the role of the π‐spacer and additional donor of the sensitizers on the overall performance of the DSSCs.

The design of a new series of β3-Adrenergic receptor (β3-AdrR) antagonists is described. The use of a spiro building block in the core of the molecule provided novel compounds with reduced aromaticity and antagonist activity at the human β3-AdrR. A shortening of this core and exploration of a series of sulfonamide derivatives produced compounds with good selectivity over β1-AdrR and β2-AdrR. Alternative substitutions on the terminal aromatic rings produced compounds with further improvements in selectivity, particularly with respect to β2-AdrR. Finally, the incorporation of heteroatoms into the fused aromatic ring provided significant improvements in solubility. One compound from the series was shown to antagonize the effect of an exogenously administered β3-AdrR agonist on left ventricular pressure in the rat, making this a series of high interest for further Lead Optimization.

Feature extraction is a collection of the necessary detailed information from the given source, which holds the information for further analysis. The quality of the fused image depends on many parameters, particularly its directional selectivity and shift-invariance. On the other hand, the traditional wavelet-based transforms produce ringing distortions and artifacts due to poor directionality and shift invariance. The Dual-Tree Complex Wavelet Transforms (DTCWT) combined with Stationary Wavelet Transform (SWT) as a hybrid wavelet fusion algorithm overcomes the deficiencies of the traditional wavelet-based fusion algorithm and preserves the directional and shift invariance properties. The purpose of SWT is to decompose the given source image into approximate and detailed sub-bands. Further, approximate sub-bands of the given source are decomposed with DTCWT. In this extraction, low-frequency components are considered to implement Texture Energy Measures (TEM), and high-frequency components are considered to implement the absolute-maximum fusion rule. For the detailed sub-bands, the absolute-maximum fusion rule is implemented. The texture energy rules have significantly classified the image and improved the output image’s accuracy after fusion. Finally, inverse SWT is applied to generate an extended fused image. Experimental results are evaluated to show that the proposed approach outperforms approaches reported earlier. This paper proposes a fusion method based on SWT, DTCWT, and TEM to address the inherent defects of both the Parameter Adaptive-Dual Channel Pulse coupled neural network (PA-DCPCNN) and Multiscale Transform-Convolutional Sparse Representation (MST-CSR).

Heterojunction Cu(In,Ga)Se2 (CIGS) solar cells comprise a substrate/Mo/CIGS/CdS/i-ZnO/ZnO:Al. Here, Al-doped zinc oxide (AZO) films were deposited by magnetron sputtering, and the substrate temperature was optimized for CIGS solar cells with two types of CIGS light absorbers with different material properties fabricated by three-stage co-evaporation and two-step metallization followed by sulfurization after selenization (SAS). The microstructure and optoelectronic properties of the AZO thin films fabricated at different substrate temperatures (150–550 °C) were analyzed along with their effects on the CIGS solar cell performance. X-ray diffraction results confirmed that all the deposited AZO films have a hexagonal wurtzite crystal structure regardless of substrate temperature. The optical and electrical properties of the AZO films improved significantly with increasing substrate temperature. Photovoltaic performances of the two types of CIGS solar cells were influenced by changes in the AZO substrate temperature. For the three-stage co-evaporated CIGS cell, as the sputter-deposition temperature of the AZO layer was raised from 150 °C to 550 °C, the efficiencies of CIGS devices decreased monotonically, which suggests the optimum AZO deposition temperature is 150 °C. In contrast, the cell efficiency of CIGS devices fabricated using the two-step SAS-processed CIGS absorbers improved with increasing the AZO deposition temperature from 150 to 350 °C. However, the rise in AZO deposition temperature to 550 °C decreased the cell efficiency, indicating that the optimum AZO deposition temperature was 350 °C. The findings of this study provide insights for the efficient fabrication of CIGS solar cells considering the correlation between CIGS absorber characteristics and AZO layer deposition temperature.

Abstract Herein, we report the development of two new low‐cost 9‐(2‐ethylhexyl)‐9H‐carbazoles carrying the mono/dimethoxyphenyl substituted cyanovinylene units symmetrically at 3‐ and 6‐positions of the carbazole core (CZ1‐2), as potential hole‐transporting materials (HTMs) for perovskite solar cell (PSC) application. The current work highlights their structural, photophysical, electrochemical, theoretical, and photoelectrochemical studies, including evaluation of their structure‐property relationships. Evidently, the optical studies showcased their excellent fluorescence ability due to their push‐pull natured structure; their λabs and λemi values were found to be in the order of 410–430 nm and 530–560 nm, respectively, with a bandgap in the range of 2.5–2.6 eV. Further, their theoretical studies, performed by using the DFT simulations clearly revealed in‐depth information on their molecular geometries, FMO, and electronic properties. Finally, new PSCs were fabricated successfully by employing CZ1‐2 as HTMs to evaluate their photovoltaic performances. Their results indicated that the device with CZ1 displayed enhanced PCE of 2.55% (JSC = 7.85 mA/cm2, VOC = 0.79 V and FF = 40%) than the cell with CZ2 (PCE = 1.71%, JSC = 8.15 mA/cm2, VOC = 0.4 V, FF = 49%) and the obtained data are well comparable with reference, Sipro‐OMeTAD (PCE = 4.76%, JSC = 12.27 mA/cm2, VOC = 0.84 V, FF = 45%). Conclusively, the study furnishes a deeper understanding of the intricacies involved in the structural modification of in low‐cost HTM in achieving an enhanced performance of the devices.

Coronary artery disease (CAD) is one of the most common causes of heart ailments; many patients with CAD do not exhibit initial symptoms. An electrocardiogram (ECG) is a diagnostic tool widely used to capture the abnormal activity of the heart and help with diagnoses. Assessing ECG signals may be challenging and time-consuming. Identifying abnormal ECG morphologies, especially in low amplitude curves, may be prone to error. Hence, a system that can automatically detect and assess the ECG and treadmill test ECG (TMT-ECG) signals will be helpful to the medical industry in detecting CAD. In the present work, we developed an intelligent system that can predict CAD, based on ECG and TMT signals more accurately than any other system developed thus far. The distinct convolutional neural network (CNN) architecture deals with single-lead and multi-lead (12-lead) ECG and TMT-ECG data effectively. While most artificial intelligence-based systems rely on the universal dataset, the current work used clinical lab data collected from a renowned hospital in the neighborhood. ECG and TMT-ECG graphs of normal and CAD patients were collected in the form of scanned reports. One-dimensional ECG data with all possible features were extracted from the scanned report with the help of a modified image processing method. This feature extraction procedure was integrated with the optimized architecture of the CNN model leading to a novel prediction system for CAD. The automated computer-assisted system helps in the detection and medication of CAD with a high prediction accuracy of 99%.

Wet ball milling was used for the synthesis of Cu2ZnSnSe4 (CZTSe) nanoparticles with a kesterite structure. The prepared nanoparticles were used for ink formulation. Surfactants and binders were added to improve the ink stability, prevent agglomeration, and enhance ink adhesion. The films deposited via spin coating were annealed at different temperatures using a rapid thermal processing system in the presence of selenium powder in an inert environment. Analytical techniques, such as X-ray diffraction, Raman spectroscopy, and Fourier-transform infrared spectroscopy, were used to confirm the formation of CZTSe nanoparticles with a single-phase, crystalline kesterite structure. Field-emission scanning electron microscopy and energy-dispersive X-ray spectroscopy were used to study the surface morphology and chemical composition of the thin films before and after annealing, with and without the sodium solution. The optoelectrical properties were investigated using ultraviolet-visible spectroscopy and Hall measurements. All the prepared CZTSe thin films exhibited a p-type nature with an optical bandgap in the range of 0.82–1.02 eV. The open-circuit voltage and fill factor of the CZTSe-based devices increased from 266 to 335 mV and from 37.79% to 44.19%, respectively, indicating a decrease in the number of recombination centers after Na incorporation.

Energy consumption and environmental pollution are major issues faced by the world. The present study introduces a single solution using SnS2 for these two major global problems. SnS2 nanoparticles and thin films were explored as an adsorbent to remove organic toxic materials (Rhodamine B (RhB)) from water and an alternative to the toxic cadmium sulfide (CdS) buffer for thin-film solar cells, respectively. Primary characterization tools such as X-ray photoelectron spectroscopy (XPS), Raman, X-ray diffraction (XRD), and UV-Vis-NIR spectroscopy were used to analyze the SnS2 nanoparticles and thin films. At a reaction time of 180 min, 0.4 g/L of SnS2 nanoparticles showed the highest adsorption capacity of 85% for RhB (10 ppm), indicating that SnS2 is an appropriate adsorbent. The fabricated Cu(In,Ga)Se2 (CIGS) device with SnS2 as a buffer showed a conversion efficiency (~5.1%) close to that (~7.5%) of a device fabricated with the conventional CdS buffer, suggesting that SnS2 has potential as an alternative buffer.

The rapid research progress in tin-based binary sulfides (SnxSy = o-SnS, c-SnS, SnS2, and Sn2S3) by the solution process has opened a new path not only for photovoltaics to generate clean energy at ultra-low costs but also for photocatalytic and thermoelectric applications. Fascinated by their prosperous developments, a fundamental understanding of the SnxSy thin film growth with respect to the deposition parameters is necessary to enhance the film quality and device performance. Therefore, the present review article initially delivers all-inclusive information such as structural characteristics, optical characteristics, and electrical characteristics of SnxSy. Next, an overview of the chemical bath deposition of SnxSy thin films and the influence of each deposition parameter on the growth and physical properties of SnxSy are interestingly outlined.

A series of novel (isopropylidene) uridine-[1,2,3]triazole hybrids (3a–3n) were efficiently synthesized via the copper-catalyzed azide–alkyne cycloaddition (CuAAC) from N-propargyl 2′,3′-O-(isopropylidene) uridine with different aryl azides. All the synthesized compounds were screened for their in vitro anticancer and antibacterial activities. The anticancer activity results revealed that compounds 3d and 3f have registered equipotent activity against MCF-7 and 3n has shown excellent activity against HeLa in comparison with the standard drug Cisplatin. Remaining compounds have shown moderate to good anticancer activity against MCF-7 and HeLa cell lines. The antibacterial activity screening results revealed that, compounds 3b and 3n have shown excellent inhibition against Escherichia coli and Bacillus subtilis, 3d against Proteus vulgaris, 3k against Staphylococcus aureus and 3l against S. aureus and B. subtilis have shown equipotent activity in comparison with the standard drug Streptomycin.

A series of novel (3-aryl-1,2-oxazol-5-yl) methyl 6-fluoro-4-oxo-4H- -chromene-2-carboxylate derivatives (C1-C12) were synthesized by Cu (I) catalyzed reaction of in situ generated nitrile oxides with prop-2-yn-1-yl 6-fluoro-4-oxo-4H-chromene-2-carboxylate in good yields and investigated their antioxidant and antimicrobial activities. Among all the synthesized compounds, C1 (IC50: 16.43 ± 0.57 μM) and C12 (IC50:15.98 ± 0.72 μM) have registered good antioxidant activity as compared to the standard drug Trolox. Compound-C1, C3, and C6 have registered very good inhibition against all gram-positive and gram-negative bacterial strains with MIC values ranging from 9.375 to 37.5 (μg mL-1). Compound-C7, C8, C9, C10, and C11 have registered good inhibition against B. subtilis and S. aureus with MIC values ranging from 18.75 to 37.5 (μg mL-1). Compound-C10 and C11 against P. aero-ginosa have shown prominent activity than the standard drug Penicillin (MIC: 12.5 μg mL-1) with MIC 9.375 μg mL-1 (~ 1.33 fold potent than Penicillin). Compound-C7, C8, and C9 have registered good to moderate antifungal activity against four tested fungal strains with MIC values ranging from 18.75 and 37.5 μg mL-1

Tin sulfide polymorph (π-SnS) nanoparticles exhibit promising optoelectrical characteristics for photovoltaic and hydrogen production performance, mainly because of the possibility of tuning their properties by adjusting the synthesis conditions. This study demonstrates a chemical approach to synthesize π-SnS nanoparticles and the engineering of their properties by altering the Sn precursor concentration (from 0.04 M to 0.20 M). X-ray diffraction and Raman studies confirmed the presence of pure cubic SnS phase nanoparticles with good crystallinity. SEM images indicated the group of cloudy shaped grains, and XPS results confirmed the presence of Sn and S in the synthesized nanoparticles. Optical studies revealed that the estimated energy bandgap values of the as-synthesized π-SnS nanoparticles varied from 1.52 to 1.68 eV. This work highlights the effects of the Sn precursor concentration on the properties of the π-SnS nanoparticles and describes the bandgap engineering process. Optimized π-SnS nanoparticles were used to deposit nanocrystalline π-SnS thin films using the drop-casting technique, and their physical properties were improved by annealing (300 °C for 2 h).

A graphene−cadmium sulfide (Gr−CdS) nanocomposite was prepared by a chemical solution method, and its material properties were characterized by several analysis techniques. The synthesized pure CdS nanoparticles (NPs) and Gr−CdS nanocomposites were confirmed to have a stoichiometric atomic ratio (Cd/S = 1:1). The Cd 3d and S 2p peaks of the Gr−CdS nanocomposite appeared at lower binding energies compared to those of the pure CdS NPs according to X-ray photoelectron spectroscopy analyses. The formation of the Gr−CdS nanocomposite was also evidenced by the structural analysis using Raman spectroscopy and X-ray diffraction. Transmission electron microscopy confirmed that CdS NPs were uniformly distributed on the graphene sheets. The absorption spectra of both the Gr−CdS nanocomposite and pure CdS NPs thin films showed an absorption edge at 550 nm related to the energy band gap of CdS (~2.42 eV). The Cu(In,Ga)Se2 thin film photovoltaic device with Gr−CdS nanocomposite buffer layer showed a higher electrical conversion efficiency than that with pure CdS NPs thin film buffer layer. In addition, the water splitting efficiency of the Gr−CdS nanocomposite was almost three times higher than that of pure CdS NPs.

A series of new 4-aryl-2’-[(4-hydroxyphenyl)thio]-6oxo-1,6-dihydro-2,4’-bipyridine-5-carbonitriles (3a–k) and 6-amino-4aryl-2’-[(4-hydroxyphenyl)thio]-2,4’-bipyridine-5-carbonitriles (4a–h) were synthesized from 4-hydroxythiophenol (1). The reaction of 4-hydroxythiophenol with 4-acetyl-2-chloropyridine yielded 1-{2-[(4-hydroxyphenyl)thio]pyridin-4-yl}ethanone (2). Further treatment of 2 with ethyl cyanoacetate in the presence of ammonium acetate with various aromatic aldehydes furnished the compounds 3a–k. On the other hand, condensation of 2 with aromatic aldehydes in the presence of alcoholic malononitrile in ammonium acetate gave compounds 4a–h. The structures of the newly synthesized compounds were established on the basis of their elemental analysis, as well as their IR, 1H- and 13C-NMR and mass spectral data. All the title compounds were subjected to in vitro antibacterial testing against two strains and antifungal screening against two fungi. Some of the compounds showed promising activity.

A series of new 4-aryl-2'-[(4-hydroxyphenyl)thio]-6oxo-1,6-dihydro- 2,4'-bipyridine-5-carbonitriles (3a-k) and 6-amino-4aryl-2'-[(4-hydroxyphenyl) thio]-2,4'-bipyridine-5-carbonitriles (4a-h) were synthesized from 4-hydroxythiophenol (1). The reaction of 4-hydroxythiophenol with 4-acetyl-2-chloropyridine yielded 1-{2-[(4-hydroxyphenyl)thio]pyridin-4-yl}ethanone (2). Further treatment of 2 with ethyl cyanoacetate in the presence of ammonium acetate with various aromatic aldehydes furnished the compounds 3a-k. On the other hand, condensation of 2 with aromatic aldehydes in the presence of alcoholic malononitrile in ammonium acetate gave compounds 4a-h. The structures of the newly synthesized compounds were established on the basis of their elemental analysis, as well as their IR, 1H- and 13C-NMR and mass spectral data. All the title compounds were subjected to in vitro antibacterial testing against two strains and antifungal screening against two fungi. Some of the compounds showed promising activity.

In the recent past, room-temperature ionic liquids (RTILs) are being explored for possible applications in nuclear fuel cycle. RTILs are being studied as an alternative to the diluent, n-dodecane (n-DD), in aqueous reprocessing and as possible substitute to high-temperature molten salts in nonaqueous reprocessing applications. This paper deals with the current status of the electrochemical research aimed at the recovery of actinides and fission products using room-temperature ionic liquid as medium. The dissolution of actinide and lanthanide oxides in ionic liquid media and the electrochemical behavior of the resultant solutions are discussed in this paper.