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Manganese oxides (MnO2) with nanowire morphology materials are promising candidates for improving oxygen evolution and oxygen reduction reaction (OER/ORR) performance. In this work, we developed transition metal cation doping strategy into the α‐MnO2 tunnel structure to tune the Mn oxidation states and control the uniform nanowire morphology, crystalline structure to investigate the effect of doping over bifunctional activity. The single Ni2+ cation doping in α‐MnO2 with various loading concentrations resulted in 8Ni−MnO2 exhibiting remarkable OER and ORR activity owing to their excessive concentration of Mn3+ and Mn4+ octahedral sites respectively. Further, Co2+ cation doping in 8Ni−MnO2 leads to an enhanced synergistic effect that significantly improves the fraction of Mn3+ quantity which is confirmed by average oxidation state. For electrochemical OER performance, 8Co−8Ni−MnO2 exhibits a potential of 1.77 V, Tafel slope value of 68 mV dec−1 and lower charge transfer resistance and it is active in ORR with more positive onset potential of 0.90 V, half‐wave potential of 0.80 V, better current density (4.7 mA cm−2) and a four‐electron pathway. Moreover, bifunctional activity (ΔE=EOER@10 mA cm−2 – ORR@E1/2) of 8Co−8Ni−MnO2 demonstrated 0.97 V, indicates an excellent activity in alkaline electrolyte solution. [ABSTRACT FROM AUTHOR]

Fungal pathogens mainly Candida and Cryptococcus species causes serious life-threating infections to humans, especially in individuals who are immunocompromised. Increasing frequency of antifungal drug resistance along with paucity of FDA-approved drugs suggest a dire need for new antifungal drugs. Our screening of newly synthesized spirooxindole heterocyclic hybrid compounds revealed that the novel small molecule, DPA-3, has potent antifungal activity without inducing mammalian cell cytotoxicity. Furthermore, DPA-3 significantly reduced hyphal and biofilm formation of Candida albicans ATCC 10231 strain, out-competing two FDA approved antifungal drugs. The results of our study conclude that DPA-3 is a compelling candidate for further development as an antifungal drug. [ABSTRACT FROM AUTHOR]

Divalent ferrite nano-crystalline materials subjected to shock wave recovery analysis bringing about prolific outcomes have received widespread attention among the materials scientists due to their outstanding contribution that has fueled the enrichment of science involving high-pressure ferrites which act as the focal-point of the current research theme. On those lines, we intend to provide the Raman spectroscopic and electrochemical measurements of manganese ferrite nanoparticles (MnFe2O4 NPs) at dynamic shocked conditions. Raman spectroscopic analysis has revealed the stability of the tetrahedral (A-site) and the octahedral (B-sites) sites of Mn2+ ions as well as Fe3+ ions at shocked conditions. Cyclic-voltammetry (CV-analysis) and impedance spectroscopic measurements of the shocked samples demonstrate the electro-chemical properties of MnFe2O4 NPs whose electrical conductivity is found to have reduced while increasing the number of shock pulses. The consolidated results provide the solid evidence that the test sample's crystal structure does not undergo any crystallographic phase transitions or mixed spinel states at shocked conditions. [ABSTRACT FROM AUTHOR]

Microbial infections together with rising drug resistance pose a threat to immunocompromised individual. In this perspective, compounds with spirooxindolopyrrolidine play a significant role in research on antimicrobial drug delivery research owing to their various pharmaceutical activities. Spiroheterocyclic compounds are present in number of medications as active motif due to their exceptional structural properties which enable for easy interaction with the protein of the biological target. Inspired by this biological precedent encouraged to synthesize a new class of dispirooxindole fused pyrrolidine heterocycles via a three-component cycloaddition strategy. The new class of structurally intriguing spirooxindolopyrrolidines were synthesized through three component cycloaddition process and the structure of products were assigned through spectroscopic analysis. The newly synthesized compounds were assessed for their antimicrobial sensitivity test with standard Kirby Bauer method with common drugs. The structurally unexplored hybrid heterocycles fused spirooxindolopyrrolidine exhibited excellent antimicrobial activity against the common nosocomial microbial pathogens. Of four compounds, the compound bearing a chlorine atom on the aryl ring (4a) exhibited significant antimicrobial activity (zone of inhibition: 9.00 ± 1.00–17.00 ± 0.35 mm and MIC: 16.00–256.00 μg/mL) against selected nosocomial infection causing microbial pathogens. Hence, the compound 4a has been considered as an effective drug of interest in therapeutic field for compacting infectious diseases causing pathogens. With an aim of developing more effective and economically more affordable antimicrobial leads with a unique mechanism of action, we have designed and synthesized structurally diverse spirooxindolopyrrolidine tethered hybrids that has been assayed against multidrug resistant nosocomial pathogens. The regioisomer having chloro substituted on the phenyl ring showed potent activity when compared to standard drug. Future studies are required to explicate the pharmacological properties of new hybrid heterocycles that have been synthesized in our laboratory for the novel therapeutic development. [ABSTRACT FROM AUTHOR]

Aggressive antimicrobial infections together with an increasing in resistance to antimicrobial medications cause a threat to immunocompromised individual. In this context, spiro compounds play an important role in drug discovery research due to their diverse biological activities including antimicrobial activity which is well documented in literature, because of their unique structural properties allow for easy interaction with the target enzyme of the biological system. This biological precedent encouraged us to design and synthesis of novel dispirooxindolopyrrolidine hybrid heterocycles via multicomponent cycloaddition protocol. Novel class of dispirooxindolopyrrolidine hybrid heterocycles has been synthesized by multicomponent 1,3-dipolar cycloaddition methodology and the structure of the products was determined through spectroscopic analysis. The synthesized organic compounds were evaluated for their antimicrobial activities using sensitivity test with standard agar well diffusion method. The synthesized new class of dispiropyrrolidine embedded indandione hybrids showed significant antimicrobial activity against carbapenemase producing Klebsiella pneumoniae (CKPs) isolated from hospital patients. Compound that possessing chlorine substituted on the aryl ring exhibited more potent antimicrobial activities and the zone of inhibitions was observed between 7.00 ± 0.09 and 18.40 ± 0.70 mm. The MIC value of compound 4b was 0.030 mg/mL against tested CKP. A new class of dispiropyrrolidine heterocyclic hybrids were synthesized in good to excellent yield employing multicomponent 1,3-dipolar cycloaddition strategy. Among them, compounds bearing 4-chloro substituted on the aryl ring exhibited notable activity just equal to the standard drug, ciprofloxacin. Future studies are needed to elucidate the pharmacological properties of new compounds that were synthesized in our laboratory for the novel therapeutic development. [ABSTRACT FROM AUTHOR]

In this communication, we report the switchable phase transition occurring between the crystalline (C) and amorphous (A) states of CuSO4·5H2O, influenced by dynamic shock waves, and the results have been evaluated by X-ray diffraction and Raman spectroscopic techniques. The present experimental findings could promote a paradigm shift in identifying new multifunctional switching materials influenced by impact of shock waves. [ABSTRACT FROM AUTHOR]

A series of 4‐unsubstituted fused quinoline derivatives, including the biologically significant 5‐deazaflavin analogs and 6H‐chromeno[4,3‐b]quinolin‐6‐ones, were synthesized from easily accessible N‐(2‐aminobenzylidene)‐4‐methylanilines and heterocyclic 1,3‐dicarbonyl compounds. The reaction was carried out in water in the absence of any catalyst to access the products in high yields. The complications associated with the stability of 2‐aminoarylaldehydes were resolved by using the stable equivalent N‐(2‐aminobenzylidene)‐4‐methylanilines. [ABSTRACT FROM AUTHOR]

This research work probes into the crystallographic and magnetic structural stability of barium ferrite nanoparticles (BaFe2O4 NPs) at dynamic shock wave-exposed conditions. Barium ferrite NPs have been prepared by co-precipitation method and the structural stability of the title ferrite has been scrutinized subsequent to the impact of shock waves (Mach number 2.2) at different counts of shocks viz., 50, 100 and 150, respectively, and their performance on shock resistance has been analyzed by the techniques of X-ray diffraction (XRD), ultra-violet diffused reflectance spectroscopy (UV-DRS), and vibrating sample magnetometry (VSM). Based on the results of the observed analytical measurements, it is substantiated that the test sample has not undergone any of the crystallographic phase transitions even though it has the crystal structure of polymorphism which manifests as the viable witness for the structural stability of the test sample that has been also authenticated by the XRD results. Very few slight changes are observed in the optical and magnetic properties of BaFe2O4 NPs at shocked conditions. More interestingly, the existence of mixed magnetic phase (ferro and anti-ferromagnetic) is witnessed at 50 and 100 shocked conditions because of the shock wave-induced directional disorder of the spin orientations of the test samples which is typically called "kink behavior". The observed results reveal that the divalent ferrite NPs of BaFe2O4 have high shock resistance than that of the technologically important ferrites such as ZnFe2O4 and α-Fe2O3 NPs. Hence, the title material could be considered as a prospective candidate for the aerospace device fabrication because of the exceptional stability of its structure against the shock wave impact. [ABSTRACT FROM AUTHOR]

In the present research article, the structural stability and performance of dye-doped potassium dihydrogen phosphate (KDP) powder samples were assessed under loading of dynamic shock waves. The obtained powder x-ray diffraction (XRD) profiles revealed that orientation defects and micro-distortions occurred in the crystalline phase due to the impact of shock waves. The results show that the abovementioned structural parameters were significantly altered, whereas the shocks did not lead to any structural phase transformation even when loading 100 shock waves for all the KDP samples. Hence, we suggest that KDP crystals have structural stability against dynamic shock wave impacts. [ABSTRACT FROM AUTHOR]

Shock wave recovery experiments have been performed on a few nano-materials so far and the results show that it is very much possible to obtain tangible evidence for the stability of the materials at exposed conditions which is similar to that of the one prevailing at extreme environmental conditions. The title material of ZnO nanorods (ZnO NRs) have been synthesized by hydrothermal method and shock wave recovery experiment has been employed for ZnO NRs by utilizing a table-top pressure driven shock tube. For the present research work, we intend to investigate the optical and molecular vibrational characteristics of ZnO NRs at shocked conditions using UV-DRS and Raman spectroscopy, respectively. UV-DRS spectroscopic study reveals that the title material is highly stable in the visible region whereas its transmittance is slightly reduced in the UV region. The optical absorption of ZnO NRs is found to be increasing from 0.64 to 0.95 with respect to the number of shock pulses. The plot of the direct band gap shows that no phase transformation has occurred in ZnO NRs. Raman spectroscopic studies also reveal that ZnO NRs have stable crystalline system against the impact of shock waves. Due to the outstanding optical and structural properties, ZnO NRs are suggested for the space-related device applications. [ABSTRACT FROM AUTHOR]

As per the current trend in science and technology, the present strategic sectors which are focusing on the development of novel materials are continually relying very strongly on the materials science researchers who are in the forefront to fulfill the industrial requirements and expectations in terms of efficiency and stability for the materials. Based on their requirements, dissipation of the energy storage is one of the primary necessities rather than to increase the capacity of energy storage. Hence, it is imperative to find the potential materials to fulfill the requirements so that the journey of this search is still an ongoing process. The present investigation deals with the measurement of the ability of shock wave resistance for brookite TiO2 at dynamic shock wave-loaded conditions by utilizing diffraction and spectroscopic methods. Based on the assessments of the above-mentioned techniques, brookite phase remained stable even at 300 shocks indicating that the brookite phase is a highly stable phase, and it could be noted that anatase TiO2 has undergone rutile phase at shocked conditions. Hence, brookite TiO2 is considered as a high shock-resistant material. [ABSTRACT FROM AUTHOR]

• The (E)-2-hydroxy-5-(((4-(N-(thiazol-2-yl) sulfamoyl) phenyl) imino) methyl) benzoic acid is an optical material, because it is showing good fluorescence spectrum. • Electronic properties, FMO and MEP were analysed by using different solvents. • Using the DLPNO-CCSD(T), the most stable dissociation energies are confirmed in 5FSATH-water complex. • The active sites and interaction were determined using ELF, LOL, and RDG. • The antimicrobial activity confirms our synthesized compound moderate activity. The molecular docking experiment showed 5FSATH had an extremely high binding affinity score. The Schiff base (5FSATH) was synthesized and characterized by different experimental techniques. In the context of local energy decomposition analysis (LED), the binding energy of 5FSATH-water interaction is determined to be -15.63 kcal/mol, while the bond distance between the two objects is measured to be 1.9781 A°. The absorption spectrum was recorded using different solvents like DMSO, water, and chloroform. The experimental absorption spectrum wavelengths 206, 220, and 300 nm, were recorded from DMSO solvent. In the emission (fluorescence) spectrum we observed three different wavelengths such as 352, 510, and 609 nm. For the calculated NMR spectrum, used the standard GIAO method and DMSO as the solvent. The HOMO-LUMO analysis indicates the charge transfer within the molecule, it is calculated by different solvents. NBO confirms the synthesized compound stability, hyper conjugative interaction, and charge delocalization. To test for antibacterial and antifungal activity, an agar disc well diffusion method is utilized. Synthesized compound tested against Escherichia coli, Candida albicans, Staphylococcus aureus, and Streptococcus pneumoniae microorganisms. Amoxicillin was used as the reference drug for testing antibacterial and antifungal activity. According to the findings of the antimicrobial activity, the result of the molecular docking experiment showed that the compound 5FSATH had an extremely high binding affinity score. [Display omitted] [ABSTRACT FROM AUTHOR]

The significance of orientational and (ro)vibrational excitations on the K( 2 S) + H 2 ( X 1 Σ g + ) reaction dynamics is presented here by performing the exact time-dependent wavepacket calculations using the Coriolis coupling (CC) approach. Employing the new accurate ab initio ground electronic surface 1 2 A ′ reported by Yuan et al. (2018), the dynamical quantities such as integral cross sections and thermal rate constants are computed within the CC and CS (centrifugal sudden) methods. All partial wave contributions of J (total angular momentum) up to 90 are required to get the convergence in dynamical results up to the collision energy of 3.5 eV. The present study attests that the ground and first vibrational level dynamics is insignificant. For v = 2 , the reaction probability is monotonically increasing, followed by the onset noted near 1.25 eV, as a function of collision energy up to 3.5 eV. Further, the kinematic effects (replacing H by D atom) on the title system is also performed and found that the KH product formation is more favored than the KD product via HD depletion path. [ABSTRACT FROM AUTHOR]