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Copyright of Journal of Surgical Arts / Cerrahi Sanatlar Dergisi is the property of Journal of Surgical Arts / Cerrahi Sanatlar Dergisi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The present investigation involves synthesis and photo-electrochemical characterizations of the multi-chalcogenide Bi–S–Se matrices along with their binary counterparts, low energy Bi 2 Se 3 and relatively high energy Bi 2 S 3 semiconductors. These films were developed on FTO glass substrates through simple and cost effective galvanostatic co-deposition technique. Bi 2 Se 3 films by virtue of its considerably high absorption coefficient and carrier density, exhibit superior photo-conversion efficiency, however, suffers from inferior stability compared to Bi 2 S 3. In order to achieve desired photo-electrochemical properties including a reasonable compromise between PCE and stability of the materials, different compositions of nanocrystalline Bi–S–Se film matrices were subjected to various physicochemical and electrochemical characterization techniques. The self-controlled particle size/growth during the composite formulation has been reflected in FE-SEM and XRD analysis of the set of films and a modulated band gap ranging between 1.13 and 1.34 eV was obtained depending on the S loading in the matrices. Electrochemical impedance spectroscopic measurements elucidate on the charge transfer resistance at the electrode-electrolyte interface and the Mott-Schottky plots reveal the n -type nature of the synthesized films validating their suitability as photo-anode. Although the bare Bi 2 Se 3 films display better performance in terms of photo-current output, the Bi–S–Se composite matrices prove their candidature as potentially durable anode material in solar cells, as justified by successive Tafel and chronoamperometric analysis. The performance output of the photo-anodes demonstrate that at low-level of sulfur in the sulfoselenide matrices, the conversion efficiency was reduced to 2.53% from that of Bi 2 Se 3 (3.65%); however, the fill factor was raised to 26.32% showing better photo-response with improved photo absorption capability, and most strikingly, the photo degradation was substantially arrested by almost 10-folds in the composite matrices. Image 1 • GrV-VI SC films with multiple chalcogens fabricated through electro-co-deposition. • Particle size was modulated with variable sulfur level in the matrix. • Composite films of BiSSe acquire much improved stability compared to Bi 2 Se 3 films. • Films with relatively compromised PCE at low sulfur level advocated for PEC cell. • PCE obeys carrier transport mechanism in a broken gap band structure. [ABSTRACT FROM AUTHOR]

Transition metal dichalcogenide (TMD) nanosheets (NSs) with defect-rich and vertically aligned edges are highly advantageous for various catalytic applications. However, colloidal synthesis of defect-rich NSs with thickness variation has been a challenging task. Here, we report a colloidal synthesis of 2H-MoSe 2 NSs having a large number of defects and vertically aligned edges, where the thickness is varied by changing the amount of coordinating solvent. The Se-vacancies in these NSs have introduced defect sites which are corroborated by the presence of additional vibration modes in Raman spectra. These NSs exhibit electrocatalytic hydrogen evolution reaction performances with a low overpotential (210–225 mV) at 10 mA cm - 2 current density and a small Tafel slope (54–68 mV per decade). Moreover, these MoSe 2 NSs are also employed as counter electrodes (CEs) for the fabrication of dye sensitized solar cells via a cost-effective and simplified procedure. The power conversion efficiencies of 7.02 ± 0.18 % , comparable with Pt CE ( 7.84 ± 0.10 % ) could be routinely achieved. These results demonstrate a novel synthetic strategy to prepare layered TMDs with superior catalytic applications. [ABSTRACT FROM AUTHOR]

Fully inorganic halide perovskite nanocrystals (NCs) are promising candidates for optoelectronic applications due to their beneficial properties such as their amenability to solution processing, high absorption coefficients, and high quantum yields. Various methods have been developed to prepare perovskite CsPbX 3 (X = Cl, Br, and I) NCs; however, large-scale synthesis with high-quality CsPbX 3 NCs remains challenging. In the study, we report an advanced method for the gram-scale synthesis of all-inorganic perovskite NCs via specially designed microwave-assisted synthesis, which offers uniform reaction energy transfer, excellent reproducibility, and flexible parameter tuning. The composition, size and uniformity of the CsPbBr 3 NCs have been optimized by controlling the surfactant ratio, precursor ratio, and reaction time. This systematic optimization leads to the production of gram-scale (> 0.165 g per a 100 ml reaction mixture for a single synthesis cycle) high-quality, phase-pure CsPbBr 3 NCs with a uniform size of ∼ 10 nm. These optimized NCs exhibit a sharp photoluminescence peak centered at 515 nm with a photoluminescence quantum yield of 94 % and produce excellent radioluminescence under X-ray irradiation. To test the feasibility of these NCs for use in real optoelectronic devices, a photodetector consisting of CsPbBr 3 NCs and monolayer MoS 2 was fabricated, demonstrating enhanced photosensitivity and a faster response time compared with a pure MoS 2 -based photodetector. The proposed gram-scale microwave-assisted synthesis method thus has the potential to promote the commercialization of metal halide perovskite NCs through cost-effective mass production for use in many optoelectronic applications. [Display omitted] • Colloidal CsPbBr 3 nanocrystals are mass-produced via MW-assisted synthesis. • CsPbBr 3 NCs are optimised by controlling the surfactant ratio, precursor ratio, and reaction time. • Gram-scale synthesis of high-quality, phase-pure CsPbBr 3 NCs with a uniform size of ∼10 nm. • The optimised NCs exhibit an excellent PL and RL with high quantum yield of 94 %. [ABSTRACT FROM AUTHOR]

This study reports the prevalence of extended-spectrum β-lactamase producing Escherichia coli and Klebsiella spp among septicemic neonates. Over a five year period, there were 94 isolates of Klebsiella spp and E. coli. Of these, 68 (72.3%) were ESBL producers. Forty (80%) of the Klebsiella spp isolates produced ESBL as compared to 28 (63.6%) of E. coli. [ABSTRACT FROM AUTHOR]

Water electrolysis is a highly efficient route to produce ideally clean H2 fuel with excellent energy conversion efficiency and high gravimetric energy density, without producing carbon traces, unlike steam methane reforming, and it resolves the issues of environmental contamination via replacing the conventional fossil fuel. Particular importance lies in the advancement of highly effective non-precious catalysts for the oxygen evolution reaction (OER). The electrocatalytic activity of an active catalyst mainly depends on the material conductivity, accessible catalytically active sites, and intrinsic OER reaction kinetics, which can be tuned via introducing N heteroatoms in the catalyst structure. Herein, the efficacious nitrogenation of CuS was accomplished, synthesized using a hydrothermal procedure, and characterized for its electrocatalytic activity towards OER. The nitrogen-doped CuO@CuS (N,CuO@CuS) electrocatalyst exhibited superior OER activity compared to pristine CuS (268 and 602 mV), achieving a low overpotential of 240 and 392 mV at a current density of 10 and 100 mA/cm2, respectively, ascribed to the favorable electronic structural modification triggered by nitrogen incorporation. The N,CuO@CuS also exhibits excellent endurance under varied current rates and a static potential response over 25 h with stability measured at 10 and 100 mA/cm2. [ABSTRACT FROM AUTHOR]

The pursuit of low-cost, highly efficient energy materials remains a key challenge in clean energy technology. This study introduces a hybrid heterostructure, CoMn-LDH/Fe 2 O 3 @NF, comprising Fe 2 O 3 nanosheets coated on CoMn nanowires (NWs) grown on nickel foam (NF). Notably, the heterostructure exhibits exceptional performance in the oxygen evolution reaction (OER), with remarkably low overpotentials (η) of 191 mV and 368 mV, yielding current densities (j) of 10 mA cm−2 and 500 mA cm−2, respectively. Moreover, when coupled with an efficient hydrogen evolution reaction catalyst, CoMn-LDH/Fe 2 O 3 @NF achieves j of 10 mA cm−2 and 500 mA cm−2 in overall water splitting at impressively low cell voltages of 1.48 V and 1.82 V, respectively. These exceptional advancements are attributed to the presence of electrochemically accessible active sites, rapid electron transport, and a strong synergistic effect between the Fe 2 O 3 nanosheets and CoMn-LDH NWs. This innovative hybrid heterostructure design holds tremendous potential for advancing next-generation OER catalysts, effectively addressing the demand for cost-effective and highly efficient materials. Significantly, this study contributes to advancing sustainable and viable energy technologies. [ABSTRACT FROM AUTHOR]

Supramolecular chemistry is a multidisciplinary research area mostly associated with the investigation of host–guest interactions within intricate three-dimensional (3D) molecular architectures held together reversibly by various non-covalent interactions. Continuous efforts to develop such kinds of complex host–guest systems with designer oligopyrrolic macrocyclic receptors are a rapidly growing research domain, which is deeply involved in applied supramolecular chemistry research. These host–guest supramolecular complexes can be constructed by combining suitable electron-rich oligopyrrolic donors (as a host) with complementary electron-poor guests (as acceptors), held together by the ionic force of attraction triggered by intermolecular charge/electron transfer (CT/ET) transitions. Some of these resulting CT/ET ensembles are potential candidates for the construction of efficient optoelectronic materials, optical sensors, molecular switches, etc. In this Feature Article we aim to focus on these supramolecular ensembles composed by size and shape complementary electroactive oligopyrrolic molecular containers, which are suitable for spherical guest (e.g., buckminsterfullerene) complexation. We also provide a "state-of-the-art" overview on plausible applications of these particular host–guest systems. Our aim is to cover only specific electron-rich tetrathiafulvalene (TTF)-based oligopyrrolic receptors, e.g., TTF-calix[4]pyrroles, TTF-cryptands, TTF-porphyrins and exTTF-porphyrin-based molecular motifs reported to date, along with a brief outlining of their "functional behaviour" in materials chemistry research. [ABSTRACT FROM AUTHOR]

Nanocrystals of CsPbBr3, a colloidal perovskite, are hybridized with silver nanoparticles (Ag NPs) and organic molecules (2,5‐diphenyloxazole, PPO) to improve X‐ray radioluminescence (RL). It is known that charge transfer from the PPO molecules to the CsPbBr3 nanocrystals enhances the RL efficiency of the CsPbBr3 nanocrystals. In this study, Ag NPs are introduced to further enhance the RL efficiency. The plasmonic process of the Ag NPs is activated by the PPO molecules, which contain X‐ray‐induced high‐energy charges. Subsequently, electric fields induced by the plasmonic process of the Ag NPs accelerate the charge transfer from the PPO molecules to the CsPbBr3 nanocrystals. The plasmonic effect of the Ag NPs is demonstrated by the full‐width half maximum (FWHM): the photoluminescence FWHM of the hybridized CsPbBr3 nanocrystals is reduced, whereas the RL FWHM remains unchanged. The Ag‐NP‐induced plasmonic effect improves the RL efficiency of the PPO‐decorated CsPbBr3 nanocrystals by ≈10%. The obtained results demonstrate that a plasmonic process can strengthen the RL of X‐ray scintillators for X‐ray detection and imaging. [ABSTRACT FROM AUTHOR]

Solvent-free mechanochemical synthesis of efficient and low-cost double perovskite (DP), like a cage of Prussian blue (PB) and PB analogs (PBAs), is a promising approach for different applications such as chemical sensing, energy storage, and conversion. Although the solvent-free mechanochemical grinding approach has been extensively used to create halide-based perovskites, no such reports have been made for cyanide-based double perovskites. Herein, an innovative solvent-free mechanochemical synthetic strategy is demonstrated for synthesizing Fe4[Fe(CN)6]3, Co3[Fe(CN)6]2, and Ni2[Fe(CN)6], where defect sites such as carbon–nitrogen vacancies are inherently introduced during the synthesis. Among all the synthesized PB analogs, the Ni analog manifests a considerable electrocatalytic oxygen evolution reaction (OER) with a low overpotential of 288 mV to obtain the current benchmark density of 20 mA cm−2. We hypothesize that incorporating defects, such as carbon–nitrogen vacancies, and synergistic effects contribute to high catalytic activity. Our findings pave the way for an easy and inexpensive large-scale production of earth-abundant non-toxic electrocatalysts with vacancy-mediated defects for oxygen evolution reaction. [ABSTRACT FROM AUTHOR]

Photoluminescence (PL) enhancement in graphene-covered CsPbBr 3 quantum dots is demonstrated, showing a three-orders-of-magnitude increase in intensity compared to bare CsPbBr 3. The inset illustrates the underlying mechanisms, where exciton-plasmon coupling and plasmon-photon coupling at the graphene/CsPbBr 3 interface lead to the observed super-bright emission. This study highlights the significant role of graphene in boosting the optoelectronic properties of perovskite materials. [Display omitted] • Graphene creates potential barriers that effectively prevent carrier leakage from CsPbBr 3 QDs, enhancing their PL. • By passivating surface defects, graphene significantly improves the stability and optical properties of CsPbBr 3 QDs. • Interaction between excitons and plasmons in graphene/CsPbBr 3 QDs results in a substantial enhancement of PL. The optical properties of graphene (Gr)-covered CsPbBr 3 quantum dots (QDs) were investigated using micro-photoluminescence spectroscopy, revealing a remarkable three orders of magnitude enhancement in photoluminescence (PL) intensity compared to bare CsPbBr 3 QDs. To elucidate the underlying mechanisms, we combined experimental techniques with density functional theory (DFT) calculations. DFT simulations showed that the graphene layer generates interfacial electrostatic potential barriers when in contact with the CsPbBr 3 surface, impeding carrier leakage from perovskite to graphene and enhancing radiative recombination. Additionally, graphene passivates CsPbBr 3 surface defect states, suppressing nonradiative recombination of photo-generated carriers. Our study also revealed that graphene becomes n-doped upon contact with CsPbBr 3 QDs, activating its plasmon mode. This mode resonantly couples with photo-generated excitons in the perovskite. The momentum mismatch between graphene plasmons and free-space photons is resolved through plasmon scattering at Gr/CsPbBr 3 interface corrugations, facilitating the observed super-bright emission. These findings highlight the critical role of graphene as a top contact in dramatically enhancing CsPbBr 3 QDs' PL. Our work advances the understanding of graphene-perovskite interfaces and opens new avenues for designing high-efficiency optoelectronic devices. The multifaceted enhancement mechanisms uncovered provide valuable insights for future research in nanophotonics and materials science, potentially leading to breakthroughs in light-emitting technologies. [ABSTRACT FROM AUTHOR]

[Display omitted] • A dual regulation strategy has been employed to create vacancies and the elevate intrinsic activity of the CCS/O v. • Small OER (383 mV) and HER (355 mV) overpotentials at 1000 mA cm−2 in 1 M KOH and excellent ion transport in various electrolytes. • DFT calculations reveal that excellent bifunctional OER/HER activities are due to a modulated valence state. • An electrolyzer cell exhibits a small cell voltage of 1.487 V in 6 M KOH and has good robustness against corrosive chlorine. For the efficient production of green H 2 on an industrial scale, developing durable, cost-effective electrocatalysts using earth-abundant transition-metals is crucial. Herein, we report a robust, bifunctional sulfurized CuCo 2 O 4 (CCS/O v) catalyst with engineered oxygen-vacancies, in which the metal catalyst is tunes to high valence state, significantly altering the intrinsic reaction kinetics and generating better catalytic activity for efficient ion transport in various electrolytes (neutral, seawater, alkaline simulated-seawater (ASW), and KOH). The optimized dual-strategy synthesized CCS/O v catalysts with hierarchical morphology exhibits modest overpotential of 383 and 355 mV at 1000 mA cm−2 for OER and HER, respectively, in 1 M KOH. Impressively, an electrolyzer cell (CCS/O v ||CCS/O v) demonstrates low cell-voltage of 1.487 V (6 M KOH), with excellent robustness in an ASW (1 and 2 M) environment against corrosive chlorine. The bifunctional CCS/O v ||CCS/O v catalyst outperforms a state-of-the-art paired Pt/C||RuO 2 catalyst and maintains the lowest potential response at up to 2000 mA cm−2, while demonstrating remarkably stable simultaneous O 2 and H 2 generation over 10 days at various current rates. Additionally, DFT calculations confirmed that CCS/O v catalysts demonstrate significantly enhanced HER and OER activities due to reduced H 2 O dissociation energy and strong intermediate binding energy, which is attributed to the anionic vacancy near Co3+. The excellent bifunctional performance of the hierarchical CCS/O v highlights its potential as non-precious catalyst with facile fabrication approach. [ABSTRACT FROM AUTHOR]

Abstract: One binuclear Cu(II) complex, [Cu2(L1)2(N3)2] (1), and a trinuclear Cu(II) complex, [Cu3(L2)3(μ1,1N3)2](ClO4) (2), of two potentially tridentate NNO-donor Schiff base ligands, [2-(1-(2-(4,6-dimethylpyrimidin-2-yl)hydrazono)ethyl)phenol] (HL1) and [2-((2-(4,6-dimethyl pyrimidin-2-yl) hydrazono) methyl) phenol] (HL2), have been synthesized and characterized by elemental analyses, UV–Vis IR spectroscopy, DFT and single crystal X-ray crystallography. The ligands HL1 and HL2 are [1+1] condensation products of 2-hydrazino-4,6-dimethylpyrimidine with 2-hydroxy acetophenone and salicylaldehyde respectively. In 1, the two Cu(II) centers are bridged by μ-phenoxo groups. In 2, the three Cu(II) centers are held together by two μ1,1 bridging azide ions and a phenoxo oxygen atom which binds the three metal centers and behaves as a μ3-O atom. The geometries of the complexes have been optimized using the UB3LYP level of theory. The calculation confirms that all the copper centers are five coordinate with distorted square pyramidal geometries, which is consistent with the experimental data. [Copyright &y& Elsevier]

An azo armed Schiff base chemosensor was synthesized based on a naphthalene fluorophore, which transduces greenish-yellow emission by complexing with Al3+. It emits greenish-yellow fluorescence through restricted C＝N isomerization, chelation-enhanced fluorescence, and the photo-induced electron transfer mechanism. The clear visible transformation of the achromatic ligand to a chromatic ligand by the 1 : 1 complexation with Al3+ is substantiated by ESI-MS spectra. 1H NMR, 13C NMR, and FTIR spectroscopies are used to characterize the HL. The selectivity of the HL for Al3+ in the presence of other metal ions was investigated through absorbance and fluorescence spectroscopies. The average lifetimes of HL and L–Al3+ have been evaluated using a time-resolved photoluminescence experiment to explore the sensing mechanism. The Al3+ sensing mechanism was also established by density functional theory calculations. A reversibility experiment was performed, demonstrating that Al3+ binding to HL is reversible. The pH variation on luminescence affirms that the HL can survive in physiological pH. Finally, the lower limit of detection of 5.4 × 10−7 and a good response in a cytotoxicity and cell imaging study confirm the usability of the ligand as an indelible signature of an effective biosensor for target Al3+. [ABSTRACT FROM AUTHOR]

[Display omitted] • 0D pnictogen-doped Sn(IV) perovskite SCs and NCs were synthesized. • Water-stable Sb3+/Bi3+-doped Sn(IV) perovskite show tunable emission. • Sn(IV) perovskite NCs show bright orange emission with PL QY of 41%. Water-stable, lead-free zero-dimensional (0D) organic–inorganic hybrid colloidal tin(IV) perovskite, A 2 SnX 6 (A is a monocationic organic ion and X is a halide) nanocrystals (NCs) with high photoluminescence (PL) quantum yield (QY) have rarely been explored. Herein, we report solution-processed colloidal NCs of blue light-emitting T 2 SnCl 6 and orange light-emitting T 2 Sn 1-x Sb x Cl 6 [T+ = tetramethylammonium cation] from their corresponding single crystals (SCs). These colloidal NCs are well-dispersible in non-polar solvents, thereby maintaining their bright emission. This paves the way for fabricating homogeneous thin films of these NCs. Due to organic cation (T+)-controlled large spin–orbit coupling (SOC), the T 2 Sn 1-x Sb x Cl 6 NCs exhibit bright orange emission with an enhancement in PL QY of 41% compared to their bulk counterpart. Furthermore, we explore T 2 Sn 1-x Bi x Cl 6 and T 2 Sn 1-x-y Bi x Sb y Cl 6 SCs, which show blue and green emission, respectively; the latter is attributed to the newly formed Sb 5p and Sb 5 s orbital-driven band structures confirmed by applying density functional theory (DFT) calculations. The SCs and NCs exhibit excellent stability in water under ambient conditions because of the in-situ generation of a hydrophobic and oxygen-resistant passivating layer of oxychloride in the presence of water. Our findings open a pathway for designing lead-free perovskites materials for thin-film-based optoelectronic devices. [ABSTRACT FROM AUTHOR]

[Display omitted] • Two lead-free perovskites, Cs 3 M 2 Br 9 (where M = Bi or Sb) NCs were synthesized from their corresponding bulk forms. • Bulk Cs 3 M 2 Br 9 is syntheszied in aqueous hydobromic acid. • PLQY exceeds that of their bulk counterparts. In recent years, there has been a surge in research interest surrounding all inorganic lead perovskite nanocrystals (NCs) owing to their exceptional performance in various optoelectronic devices. Nevertheless, the presence of lead and concerns regarding its toxicity and stability have cast a shadow over their potential wide-ranging applications. In this study, we present the synthesis of two lead-free all-inorganic perovskite materials, Cs 3 M 2 Br 9 (where M = Bi or Sb), in bulk form, using an aqueous halide acid medium. Additionally, we describe a top-down approach for the fabrication of two lead-free all-inorganic perovskite, Cs 3 M 2 Br 9 (M = Bi or Sb) NCs. The Cs 3 Sb 2 Br 9 NCs display a sheet-like morphology, while Cs 3 Bi 2 Br 9 NCs exhibit a cubic structure. The PL spectra of Cs 3 Sb 2 Br 9 and Cs 3 Bi 2 Br 9 NCs exhibit distinct emission peaks at 476 nm and 472 nm, respectively, with relatively narrow full width at half maximum (FWHM) of 44 nm and 38 nm, respectively. Cs 3 Sb 2 Br 9 and Cs 3 Bi 2 Br 9 NCs demonstrate excellent thermal stability up to 320 °C and 470 °C, respectively. Notably, the high photoluminescence quantum yield (PLQY) of these NCs, Cs 3 Sb 2 Br 9 NCs (31 %) and Cs 3 Bi 2 Br 9 NCs (36 %) are highly beneficial for optoelectronic applications is observed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Preparation of PCT-1 and Zr doped PCT-2. • Band-gap is modulated and supported by DFT. • More than 95 % MB dye degraded with PCT-2 (180 min). • PCT-2 displayed lesser e-/h+ pair recombination (3.02 eV) The effective mitigation of effluents in water has attracted researchers as a foremost task for addressing environmental concerns. To overcome these concerns, TiO 2 (labeled as PCT-1) and Zr-doped TiO 2 (labeled as PCT-2) nano catalysts are prepared by an efficient sol–gel protocol and their photocatalytic degradation performance of methylene blue (MB) is investigated. The structural integrity of nanostructures is determined by analytical tools. More than 96 % MB degradation is observed when PCT-2 is subjected to ultraviolet light for 180 min. Nanosized PCT-2 exhibits attractively advanced photocatalytic performance than PCT-1 owing to lower electron–hole pair recombination (3.02 eV) as well as superior photon capture via oxidation by photocatalytic response (confirmed through active species trapping scavenger tests). Furthermore, the results of bandgap are also confirmed by spin-polarized density functional theory (DFT) computations. The findings of this study indicate that band tuning is an attractive photocatalytic system for improving catalytic performance. [ABSTRACT FROM AUTHOR]

Herein, phase pure and highly crystalline Ce:LuAG nano-ceramics were fabricated using a novel, ultra-fast microwave sintering approach. The influence of microwave sintering on the microstructural, photoluminescence, and dielectric characteristics of Ce:LuAG nano-ceramic powders was examined. Microwave-assisted sintering of Ce:LuAG nano-ceramic powders yielded high crystallinity, low lattice strain, and reduced grain size. The process also improved the sintering kinetics and enhanced the surface diffusion between the grains, resulting in enhanced luminescence and dielectric properties. The Cole-Cole impedance plots showed single semicircular arcs, indicating non-Debye relaxation and a high dielectric constant in the microwave-sintered Ce:LuAG nano-ceramic and highlighting its potential for use in optoelectronics. [ABSTRACT FROM AUTHOR]

[Display omitted] • Innovative CoMn-Fe/NF heterostructure electrode design for superior supercapacitors. • Optimal heterostructure design improves ion mobility, boosts active sites, and reduces charge transfer resistance. • The CoMn-Fe/NF electrode demonstrates a remarkable specific capacitance of 2633 Fg−1 at 1 A g−1. • The CoMn-Fe/NF electrode achieves an energy density of 87.80 Wh kg−1 at 0.245 kW kg−1. The pursuit of enhanced energy storage efficiency has driven the development of hybrid electrode structures. Overcoming the limitations of single-component metal oxides regarding stability and ionic electron mobility, we have engineered a hybrid structure, CoMn-Fe/NF. This structure comprises vertically grown Fe 2 O 3 nanosheets on CoMn layered doubled hydroxide (LDH) nanowires anchored on nickel foam (NF) via a hydrothermal synthesis method. This hybrid configuration demonstrated a remarkable specific capacitance of 2633F g−1 at 1 A/g, coupled with exceptional stability. When integrated into a supercapacitor device, it achieved a high energy density of 87.80 Wh kg−1 at a power density of 0.245 kW kg−1 while maintaining outstanding cycling performance. The interconnected network of nanowires and nanosheets in CoMn-Fe/NF facilitated ion mobility and provided abundant accessible active sites, resulting in robust electrochemical activity, low resistance, and enhanced supercapacitor performance. This study introduces an innovative strategy for synthesizing electrode materials with significant potential for high-performance hybrid supercapacitors, representing a substantial advancement in the development of efficient energy storage devices. [ABSTRACT FROM AUTHOR]

A photoinduced electron transfer (PET) and chelation-enhanced fluorescence (CHEF) regulated rhodamine-azobenzene chemosensor (L) was synthesized for chemoselective detection of Al3+, Cr3+, and Cu2+ by UV–Visible absorption study whereas Al3+ and Cr3+ by fluorimetric study in EtOH-H 2 O solvent. L showed a clear fluorescence emission enhancement of 21 and 16 fold upon addition of Al3+ and Cr3+ due to the 1:1 host-guest complexation, respectively. This is first report on rhodamine-azobenzene based Cr3+ chemosensor. The complex formation, restricted imine isomerization, inhibition of PET (photo-induced electron transfer) process with the concomitant opening of the spirolactam ring induced a turn-on fluorescence response. The higher binding constants 6.7 × 103 M−1 and 3.8 × 103 M−1 for Al3+ and Cr3+, respectively and lower detection limits 1 × 10−6 M and 2 × 10−6 M for Al3+ and Cr3+, respectively in a buffered solution with high reversible nature describes the potential of L as an effective tool for detecting Al3+ and Cr3+ in a biological system with higher intracellular resolution. Finally, L was used to map the intracellular concentration of Al3+ and Cr3+ in human lymphocyte cells (HLCs) at physiological pH very effectively. Altogether, our findings will pave the way for designing new chemosensors for multiple analytes and those chemosensors will be effective for cell imaging study. Unlabelled Image • A new rhodamine-azobenzene based chemosensor was reported. • Al3+, Cr3+, and Cu2+ were detected by UV–Visible absorption study. • Cr3+ and Al3+ were distinguished by fluorimetric study. • An INHIBIT LOGIC GATE is constructed at molecular level. • The L was utilized to map the intracellular concentration of Al3+ or Cr3+ in HLCs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Precise optoelectronic and unique physiochemical properties of graphene nanomaterials. • Large surface area of graphene nanomaterials for loading biomolecules and medicine. • Potential for the conjugation of fluorescent dyes or quantum dots for bioimaging. • Recent developments in graphene nanomaterials-based biomedical equipment. Nanomaterials by virtue of their small size and enhanced surface area, present unique physicochemical properties that enjoy widespread applications in bioengineering, biomedicine, biotechnology, disease diagnosis, and therapy. In recent years, graphene and its derivatives have attracted a great deal of attention in various applications, including photovoltaics, electronics, energy storage, catalysis, sensing, and biotechnology owing to their exceptional structural, optical, thermal, mechanical, and electrical. Graphene is a two-dimensional sheet of sp2 hybridized carbon atoms of atomic thickness, which are arranged in a honeycomb crystal lattice structure. Graphene derivatives are graphene oxide (GO) and reduced graphene oxide (rGO), which are highly oxidized and less oxidized forms of graphene, respectively. Another form of graphene is graphene quantum dots (GQDs), having a size of less than 20 nm. Contemporary graphene research focuses on using graphene nanomaterials for biomedical purposes as they have a large surface area for loading biomolecules and medicine and offer the potential for the conjugation of fluorescent dyes or quantum dots for bioimaging. The present review begins with the synthesis, purification, structure, and properties of graphene nanomaterials. Then, we focussed on the biomedical application of graphene nanomaterials with special emphasis on drug delivery, bioimaging, biosensing, tissue engineering, gene delivery, and chemotherapy. The implications of graphene nanomaterials on human health and the environment have also been summarized due to their exposure to their biomedical applications. This review is anticipated to offer useful existing understanding and inspire new concepts to advance secure and effective graphene nanomaterials-based biomedical devices. [ABSTRACT FROM AUTHOR]

The pyrazole based ligands (E)-2-(3,5-dimethyl-1H-pyrazol-1-yl)-N′-(pyridin-2-ylmethylene acetohydrazide (N-PzOPyH) and (E)-5-methyl-N′-(pyridin-2-ylmethylene)-1H-pyrazole-3-carbo hydrazide (PzOPyH), a 1:1 condensation product of 2-(3,5-dimethyl-1H-pyrazol-1-yl)aceto hydrazide and 5-methylpyrazole-3-carbohydrazide with pyridine-2-carbaldehyde respectively, and their keto oxygen bridged Cd(II) complexes [Cd 2 (N-PzOPy) 2 (H 2 O) 4 ](ClO 4 ) 4 ( 1 ), [Cd 2 (PzOPy) 2 (H 2 O) 4 ](ClO 4 ) 4 ( 2 ) and [Cd 2 (PzOPy) 2 (NO 3 ) 4 ] ( 3 )] are reported. They have been characterized structurally and spectroscopically. The potential tetradentate NONN-donor ligands N-PzOPyH and PzOPyH are engaged in the coordination around the cadmium(II) center through the nitrogen atoms of pyrazole, azomethine and pyridine and the ketonic oxygen atom of the carbohydrazide group to form complexes 1 , 2 and 3 , respectively. These ligands span themselves in the equatorial plane and the pentagonal bipyramidal geometry is completed around the metal centres (with an N 3 O 4 chromophore) with two apical water molecules (for 1 and 2 ) and with two nitrate ions (for 3 ). These keto bridged Cd(II) complexes are further stabilised by supramolecular interactions, like π⋯π, C–H⋯π and H-bonding interactions. [ABSTRACT FROM AUTHOR]

For industrial high-purity hydrogen production, it is essential to develop low-cost, earth-abundant, highly-efficient, and stable electrocatalysts which deliver high current density (j) at low overpotential (η) for oxygen evolution reaction (OER). Herein, we report an active mesoporous Ni 2 P @ FePO x H y pre-electrocatalyst, which delivers high j = 1 A cm−2 at η = 360 mV in 1 M KOH with long-term durability (12 days), fulfilling all the desirable commercial criteria for OER. The electrocatalyst shows abundant interfaces between crystalline metal phosphide and amorphous phosphorus-doped metal-oxide, improving charge transfer capability and providing access to rich electroactive sites. Combined with an excellent non-noble metal-based HER catalyst, we achieve commercially required j = 500/1000 mA cm−2 at 1.65/1.715 V for full water-splitting with excellent stability in highly corrosive alkaline environment (30% KOH). The alkaline-anion-exchange-membrane water-electrolyzer (AAEMWE) fabricated for commercial viability exhibits high j of 1 A cm−2 at 1.84 V with long-term durability as an economical hydrogen production method, outperforming the state-of-the-art Pt/C – IrO 2 catalyst. [Display omitted] • Noble-metal free catalysts for oxygen evolution reactions are investigated. • Crystalline (Ni 2 P) and amorphous (FePO x H y) phases in Ni 2 P @ FePO x H y catalyst provide more electrocatalytic active sites. • The Ni 2 P @ FePO x H y catalyst shows excellent AAEMWE cell performance with a low overpotential and good stability. • The Ni 2 P @ FePO x H y catalyst exhibits a low overpotential of 360 mV for OER to deliver a high current density of 1 A cm−2. [ABSTRACT FROM AUTHOR]

[Display omitted] • A multianalyte selective fluorescent probe derived from rhodamine and phenolphthalein is synthesized. • It showed highly selective and sensitive response towards Cu2+, Fe3+ colorimetrically and Al3+, Cr3+ fluorimetrically. • Detection limits for Cu2+, Fe3+, Al3+ and Cr3+ are 1.21 µM, 1.75 µM, 2.27 µM, and 1.29 µM, respectively. • Test paper strips of the probe were prepared for rapid and selective detection for four analytes. • It is also used as a bio-imaging fluorescent probe against A549 cancer cell line. In this study, a novel rhodamine-phenolphthalein derivative (RBPF) was designed, synthesized, and characterized. RBPF exhibited the selective and sensitive colorimetric detection of Cu2+ and Fe3+ and fluorometric detection of Al3+ and Cr3+, thus functioning as a multiple-channel probe in MeOH-H 2 O (v/v = 9/1, 5 µM HEPES, pH 7.2) in the presence of other cations. A strong enhancement of the absorbance at around 555 nm was observed for the four mentioned cations. In contrast, in the presence of Al3+ and Cr3+, emissions were intensified within the red region of the spectra (583 and 586 nm, respectively). The RBPF sensor was found to bind to the metal ions at a 1:2 stoichiometric ratio. The proposed mechanism for the observed sensing behavior is the opening of the spirolactam ring of the rhodamine core in the presence of the four mentioned metal ions. The detection limits for Cu2+, Fe3+, Al3+, and Cr3+ were calculated to be 1.21 µM, 1.75 µM, 2.27 µM, and 1.29 µM, respectively. To test the practical use of the probe, TLC-based paper strips were fabricated. In addition, cell-imaging analysis of Al3+ and Cr3+ ions in the A549 cancer cell line produced promising concentration and time-dependent detection results. [ABSTRACT FROM AUTHOR]

• A phenolphthalein-aminophenol (PFAP)-based chemosensor for Al3+ was synthesized. • PFAP showed a LOD of 1.5 µM and a fast response time of 10 s. • PFAP was used to detect Al3+ in the intracellular region of the A549 cancer cells. Monitoring of excess Al3+ and its selective detection in biological and environmental samples are important tasks for researcher due to its harmful effects. Herein, we present a phenolphthalein-aminophenol derived sensor (PFAP) for the selective fluorescent response of Al3+ in an "OFF-ON" mode over a pool of analytes including eighteen cations with striking greenish emission. It has a prominent limit of detection (LOD) value (1.5 µM), fast response time (10 s) for Al3+ detection. The complexation properties of PFAP with Al3+ ions were clarified by UV–vis, 1H & 13C NMR, HRMS, and FTIR spectroscopic experiments. The recognition mechanism of PFAP for Al3+working with chelation enhanced fluorescence (CHEF) and is verified with two model compounds PF and PFAN in the light of UV–vis, PL, TRPL, and NMR experiment. To check its applicability, easily prepared test paper and TLC strip of PFAP was produced for rapid and selective onsite detection of Al3+ ions. Bio-imaging application of PFAP in human lung cancer cell lines A549 demonstrated excellent results with negligible cytotoxicity and as an excellent marker to detect traces of Al3+ ion in a time-dependent as well as concentration-dependent manner. Actual sample analysis for Al3+ with the probe PFAP produces fruitful result. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Smart material synthesis through polymer encapsulated perovskite crystals. • The materials are used for Memory Recovery application. • The role of a conducting polymer in offering better emission quality and stability of the perovskite crystals. • Impressive optical properties of polymer-perovskite composite make the material for optoelectronic devices. Impressive optical properties of organic–inorganic lead halide perovskite crystals make them suitable for optoelectronic devices. However, these crystals are unstable in water and other polar solvents and quickly lose their fluorescence which cannot be recovered by the addition of non-polar solvents. Fluorescence recovery is absolute necessity for long-term stability of perovskite in optoelectronic devices. Till date, there is no report showing mechanism of fluorescence recovery of organic–inorganic lead halide perovskite crystals. Here, we have reported the synthesis of FAPbBr 3 /polypyrrole (PPy) composites (FA = Formamidinium) for shedding light on the mechanism of fluorescence recovery in presence of N,N Dimethyl formamide or DMF. We have synthesized FAPbBr 3 crystals at room temperature and tuned their band gap from green to blue by varying the amount of surfactant. Similar study was repeated with FAPbBr 3 /PPy composites, synthesized through in situ polymerization. Encapsulation was found to improve the emission quality and purity of the colour and successfully restored the fluorescence memory which was lost in presence of DMF. The recovery was attributed to resurfacing of PPy in presence of toluene which brought the building blocks of FAPbBr 3 crystals back to the co-crystallization domain. In brief, this fundamental finding could pave the future way for achieving long-term stability of perovskite crystals in optoelectronic devices. [ABSTRACT FROM AUTHOR]

• Noble-metal free catalysts for overall water splitting reactions are investigated. • First principle calculations confirm that the remarkable HER and OER at the Co site is due to the doping of V species. • The VCoCO x @NF catalyst shows excellent AAEMWE cell performance with a low overpotential and good stability. • The VCoCO x @NF catalyst exhibits a low overpotential of 63 mV for HER and 240 mV for OER at 10 mA cm−2. Large scale, cost-efficient, durable, and non-noble metal catalysts for overall water splitting in alkaline-anion-exchange-membrane-water-electrolyzer (AAEMWE) are highly demanded for the clean hydrogen economy. Meanwhile, V- and Co-based bimetallic oxide materials were rarely reported for overall water splitting in AAEMWE. Herein, we demonstrate that the self-supported oxovanadate-doped cobalt carbonate (VCoCO x @NF) on nickel foam (NF) is a high-performance overall water-splitting catalyst in AAEMWE. The as-prepared VCoCO x @NF catalyst demonstrates high activity for both hydrogen and oxygen evolution reactions (HER and OER) in alkaline media, with a current density (j) of 10 mA cm−2 at overpotentials of 63 mV and 240 mV, respectively. Assembled as a conventional electrolyzer for overall water splitting, VCoCO x @NF as both anode and cathode in 1 M KOH operates at low cell voltages of 1.54 and 1.74 V at 10 and 100 mA cm−2, respectively, superior to the Ir/C−Pt/C@NF electrolyzer (1.59 and 1.86 V, respectively). First principle calculations show that the remarkable HER and OER at the Co site are due to the doping of V species, which reduces the overpotential by shifting the d-electron states of Co towards the Fermi-level. Besides, an AAEMWE cell fabricated with the VCoCO x @NF catalyst delivers j = 200 mA cm−2 at 2.01 V in deionized water, lower than the expensive commercial IrOx-Pt/C@Au/Ti electrolyzer (2.06 V). This finding provides the stage for large-scale hydrogen production by utilizing the V- and Co-based bimetallic oxide materials. [ABSTRACT FROM AUTHOR]

The use of organic conjugated polymers in sensors has attracted greater attention due to their application in materials technology. In the present communication, we utilized Schiff's condensation polymerization reaction for the synthesis of a novel conjugated polymer poly(tetrahexadecyl-dihydroindacenodithiophene) -alt-(p -phenylenediimine) (PIDTPD) consisting of indacenodithiophene (IDT) and p -phenylene diamine (PDA) units for use in acid vapor sensing. Conventionally, the characteristics and applications of conjugated polymers are affected by their constituents. The imine bond between the components of organic materials has received little attention compared to their active counterparts. In order to explore the practical application of conjugated polymers in sensors, we employed PIDTPD in a paper sensor and illustrated the impact of mono- and bis-protonation on the pristine material in driving a noteworthy protonation-induced color shift toward the longer wavelength region via acidochromism. Image 1 [ABSTRACT FROM AUTHOR]

• A new PET – CHEF controlled rhodamine-azobenzene based chemosensor is reported. • Chemoselection of Cu2+, Al3+, and Cr3+ by UV–vis absorption study and Al3+ and Cr3+ by fluorimetric study. • The detection limit is as low as 1.1 × 10−6 M, 1.3 × 10−6 M, and 1.5 × 10−6 M for Cu2+, Al3+, and Cr3+ respectively. • The sensor is capable to mimic an AND LOGIC GATE and can be used as onsight solid probe (paper strip). • The sensor L is cell-permeable and is utilized to map the intracellular concentration of Al3+ and Cr3+ in HLCs. The design and synthesis of red light-emitting multianalyte chemosensors have always been a challenging task because of its specific requirement of coordination pocket and selective fluorescence mechanism. Herein, we develop a chemosensor via "three birds, one stone" strategy in which we can detect three metal ions with one ligand. A highly sensitive new azo functionalized rhodamine based luminescent sensor is synthesized for selective fluorogenic recognition of Al3+, Cr3+, and chromogenic recognition of Cu2+ in ethanol : H 2 O medium in the red light-emitting zone. Among the guest metals, Cu2+ efficiently quenches the emission whereas Al3+ and Cr3+ induce increased luminescent 4.76 fold for Al3+ and 2.47 fold for Cr3+ through chelation-enhanced fluorescence (CHEF) and photo-induced electron transfer (PET) regulated mechanism with the formation of 1:1 complex. The restricted imine isomerization through complex formation inhibits ongoing PET process with the instantaneous onset of CHEF. The mechanism is in good consonance with NMR (1H &13C), FT-IR, elemental analysis, DFT, TCSPC, and pH-dependent studies. Micromolar range detection of 1.1 μM, 1.3 μM, and 1.5 μM for Cu2+, Al3+, and Cr3+ respectively, easy penetration into HLCs cells and higher imaging resolution increase its potentiality to assess Al3+ and Cr3+ in vitro. Moreover, paper strip application increases its viability as an onsite naked-eye portable solid probe. [ABSTRACT FROM AUTHOR]

While formamidinium lead iodide (FAPbI 3 ) halide perovskite (HP) exhibits improved thermal stability and a wide band gap, its practical applicability is chained due to its room temperature phase transition from pure black (α-phase) to a non-perovskite yellow (δ-phase) when exposed to humidity. This phase transition is due to the fragile ionic bonding between the cationic and anionic parts of HPs during their formation. Herein, we report the synthesis of water-stable, red-light-emitting α-phase FAPbI 3 nanocrystals (NCs) using five different amines to overcome these intrinsic phase instabilities. The structural, morphological, and electronic characterization were obtained using X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), and X-ray photoelectron spectroscopy (XPS), respectively. The photoluminescence (PL) emission and single-particle imaging bear the signature of dual emission in several amines, indicating a self-trapped excited state. Our simple strategy to stabilize the α-phase using various amine interfacial interactions could provide a better understanding and pave the way for a novel approach for the stabilization of perovskites for prolonged durations and their multifunctional applications.

The limited Mn 2+ doping that occurs in lead halide perovskites has been widely described, while the Pb 2+ doping that occurs in Mn 2+ halide perovskites has not been studied well. Generally, a large amount of doping of Mn 2+ in lead halide perovskite degrades the perovskite structure; eventually, high orange luminescence of Mn 2+ dopant has not been achieved. In our present study, we followed a reverse strategy, i.e., Pb 2+ doping in Mn 2+ halide perovskites, to increase the amount of Mn 2+ in halide perovskites through the high-energy ball milling method. This strategy yields bright-fluorescence orange light-emitting Mn 2+ -doped perovskite with a Mn/Pb ratio of 95%, which is the highest among Mn 2+ -doped perovskites. Zero-dimensional (0D) Mn 2+ perovskites and two-dimensional (2D) Pb 2+ -doped Mn 2+ -based perovskites were successfully synthesized and characterized. During the mechanochemical engineering, Pb 2+ ions partially occupy the site of Mn 2+ ions and act as a luminescence activator. Mn 2+ -based 2D perovskites with the proper amounts of Pb 2+ ions as dopant ions and phenylethylammonium (PEA + ) as dielectric organic cations show enhanced stability in water. The dual-emissive properties of these 2D-Pb 2+ -doped Mn 2+ -based perovskites were also investigated by using single-particle imaging fluorescence. We believe that these findings will pave the way for designing eco-friendly dimension and bandgap tunable layered perovskites.

We report here a nanosized "buckytrap", 1 , constructed from two bis-zinc(II) expanded-TTF (exTTF) porphyrin subunits. Two forms, 1a and 1b , differing in the axial ligands, H 2 O vs tetrahydrofuran (THF), were isolated and characterized. Discrete host-guest inclusion complexes are formed upon treatment with fullerenes as inferred from a single-crystal X-ray structural analyses of 1a with C 70 . The fullerene is found to be encapsulated within the inner pseudohexagonal cavity of 1a . In contrast, the corresponding free-base derivative ( 2 ) was found to form infinite ball-and-socket type supramolecular organic frameworks (3D-SOFs) with fullerenes, ( 2• C 60 ) n or ( 2 •C 70 ) n . This difference is ascribed to the fact that in 1a and 1b the axial positions are blocked by a H 2 O or THF ligand. Emission spectroscopic studies supported a 1:1 host-guest binding stoichiometry, allowing association constants of (2.0 ± 0.5) × 10 4 M -1 and (4.3 ± 0.9) × 10 4 M -1 to be calculated for C 60 and C 70 , respectively. Flash-photolysis time-resolved microwave conductivity (FP-TRMC) studies of solid films of the Zn-complex 1a revealed that the intrinsic charge carrier transport, i.e., pseudo-photoconductivity (ϕ∑μ), increases upon fullerene inclusion (e.g., ϕ∑μ = 1.53 × 10 -4 cm 2 V -1 s -1 for C 60 ⊂( 1a ) 2 and ϕ∑μ = 1.45 × 10 -4 cm 2 V -1 s -1 for C 70 ⊂( 1a ) 2 vs ϕ∑μ = 2.49 × 10 -5 cm 2 V -1 s -1 for 1a ) at 298 K. These findings provide support for the notion that controlling the nature of self-assembly supramolecular constructs formed from exTTF-porphyrin dimers through metalation or choice of fullerene can be used to regulate key functional features, including photoconductivity.

Ligand-assisted re-precipitation (LARP) is one of the most practicing techniques for synthesizing colloidal nanocrystals (NCs). But due to its fast reaction kinetics, it offers limited synthesis control. In the present study, we report a novel, precursor silanization-based room temperature technique unveiling slow crystallization of Cs 4 PbBr 6 /CsPbBr 3 dual-phase nanocrystals (DPNCs) protected with a dense silica cloud-like matrix. Unlike conventional LARP, we can observe the tuneable optical bandgap of the DPNCs as a function of reaction time because of the slow reaction kinetics. The as-synthesized DPNCs exhibit a high photoluminescence quantum yield (PLQY) of 76% with ultrahigh stability while retaining ∼ 100% of their initial PLQY in an ambient environment with a relative humidity of 55% for more than 1 year. DPNCs demonstrates ambient photostability of 560 h, and water stability of 25 days. This interesting precursor silanization technique developed here can be extended for the synthesis of other nanomaterials., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

For practical applications, the development of bio-compatible organic molecules as p-block ion chemosensors is critical. Herein, we report the single crystal (SC) of new pyridine-pyrazole derived Al 3+ sensor H2PPC [( Z )- N '-(2,3-dihydroxybenzylidene)-5-methyl-1-(pyridin-2-yl)-1 H -pyrazole-3-carbohydrazide] as well as its Cu-complex SC. The probe exhibits an "off-on" fluorescence response towards Al 3+ ions, and this has been modulated with different solvents. For selective detection of Al 3+ ions, a special coordination pocket in the structural backbone is advantageous. The chemosensor exhibits a submicromolar detection level (LOD = 4.78 μM) for Al 3+ . The density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations of H2PPC and [Al(HPP)2]+ (1) reveal that a change of the structural conformation of probe H2PPC upon complexation causes the pyrazole and pyridine units to create a specific cavity to tether Al 3+ , and consequently H2PPC proves to be a promising molecule for Al 3+ detection. Furthermore, the probe has been successfully used to evaluate Al 3+ as a low-cost kit using filter paper strips, and the in situ Al 3+ ion imaging in Vero cells as well as A549 cell lines shows the sensor's nuclear envelope penetrability, indicating that it has great potential for biological and environmental applications.

Two sterically crowded benzo-tetrathiafulvalene (BTTF)-annulated expanded porphyrins (BTTF7-F and BTTF8) are synthesized. Detailed photophysical investigations reveal their intrinsic intramolecular charge transfer (CT) character, originated from partial electron transfer from electron-rich TTF units to the relatively electron-deficient macrocyclic core. This finding stands in contrast to what was observed in the previously reported Figure-of-eight conformer of BTTF-annulated [28]hexaphyrin (BTTF6), in which a typical π-π* electronic transition from HOMO to LUMO was observed. However, core expansion in BTTF7-F and BTTF8 makes the oligopyrrole macrocyclic cores relatively more electron-deficient, facilitating the effective intramolecular CT process. Comparative electrochemical investigations reveal that the current generated at the oxidative region is directly proportional to the number of TTF units attached to the macrocyclic core. This work demonstrates the control of the intramolecular CT process through incremental addition of TTF units to the macrocyclic core. Facile multielectron electrochemical oxidations of these expanded porphyrins suggest that they behave like potential multielectron reservoirs., (© 2020 Wiley-VCH GmbH.)

The absence of d-orbital electrons or presence of full-filled d-orbital electrons in metal ions is a well-known Achilles' heel problem for the detection of these metal ions by a simple UV-visible study. For this reason, detection of metal ions such as Al 3+ with no d-orbital electrons or Zn 2+ with filled d-orbital electrons is a challenging task. Herein, we report a 2-naphthol-based fluorescent probe [1-(( E )-(( E )-(5-bromo-2-hydroxybenzylidene)hydrazono)methyl)naphthalen-2-ol] ( H 2 L ) that has been used to sense and discriminate Al 3+ and Zn 2+ via solvent regulation. The probe exhibits excellent selectivity and swift sensitivity toward Al 3+ in MeOH-water (9:1, v/v) and toward Zn 2+ in dimethyl sulfoxide (DMSO)-water (9:1, v/v) among various metal ions. The respective detection limit is found to be 9.78 and 3.65 μM. The sensing mechanism is attributed to multiple processes, viz., the inhibition of photo-induced electron transfer (PET) along with the introduction of chelation-enhanced emission (CHEF) and excited-state intramolecular proton transfer (ESIPT) inhibition, which are experimentally well verified by UV-vis absorption spectroscopy, emission spectroscopy, and NMR spectroscopy. The probe shows aggregation-induced emissive (AIE) response in ≥70% aqueous media as well as in the solid state. The experimental results are well corroborated by time-resolved photoluminescence (TRPL) and density functional theory (DFT) calculations. An advanced-level OR-AND-NOT logic gate has been constructed from a different chemical combinational input and emission output. The reversible recognition of both Al 3+ in MeOH-water (9:1, v/v) and Zn 2+ in DMSO-water (9:1, v/v) is also ascertained in the presence of Na 2 EDTA, enabling the construction of a molecular memory device. The probe H 2 L also detects intracellular Al 3+ /Zn 2+ ions in Hela cells. Altogether, our fundamental findings will pave the way for designing and synthesis of unique chemosensors that could be used for cell imaging studies as well as constructing molecular logic gates.

A novel Schiff base L composed of fluorescein hydrazine and a phenol functionalized moiety has been designed and prepared via cost-effective condensation reaction. The L is utilized for selective sensing of Zn 2+ over other environmental and biological relevant metal ions in aqueous alcoholic solution under physiological pH range. The binding of Zn 2+ to the receptor L is found to causes ~23 fold fluorescence enhancement of L. The 1:1 binding mode of the metal complex is established by combined UV-Vis, fluorescence, and HRMS (high-resolution mass spectroscopy) spectroscopic methods. The binding constant (K a ) for complexation and the limit of detection (LOD) of Zn 2+ is calculated to be 2.86 × 10 4  M -1 and 1.59 μM, respectively. Further photophysical investigations including steady-state, time-resolved fluorescence analysis and spectral investigations including NMR (nuclear magnetic resonance), IR (infrared spectroscopy) suggest introduction of CHEF (chelation enhance fluorescence) with the suppression of CN isomerization and PET (photo-induced electron transfer) mechanism for the strong fluorescent response towards Zn 2+ . Finally, the sensor L is successfully employed to monitor a real-time detection of Zn 2+ by means of TLC (thin layer chromatography) based paper strip. The L is used in the cell imaging study using African green monkey kidney cells (Vero cells) for the determination of exogenous Zn 2+ by Immunofluorescence Assay (IFA) process., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Two luminescent cyclometalated Pt(II)-complexes, 1•Pt and 2•Pt, respectively, were synthesized by using unsymmetrical C ∧ N ∧ N ligands having different alkyl substituents. These π-electron-rich complexes are used for sensing various electron deficient nitroaromatic explosives, e.g., 4-nitrotoluene (NT), 2,4-dinitrotoluene (DNT), 2,4,6-trinitrotoluene (TNT), and 2,4,6-trinitrophenol (TNP), in aqueous, nonaqueous, as well as in the solid state as a paper strip with maximum detection limit of ca. 10 -9 M. It was demonstrated that the sparingly soluble 2•Pt complex becomes water-soluble in the presence of all kinds of surfactants, viz., cationic (e.g., cetyltrimethylammonium bromide, CTAB), anionic (e.g., sodium dodecyl sulfate, SDS), and neutral (e.g., Triton X-100). This may be due to the incorporation of its long lyophilic tail group (-C 12 H 25 ) inside the micellar core, exposing planar Pt(II)C ∧ N ∧ N headgroup to the aqueous bulk phase. It was also observed that the extent of solubility of these Pt(II)-complexes in micellar media strongly depends on the length of the existing alkyl chain. For instance, the presence of longer dodecyl chain makes 2•Pt complex ca. 1000-fold more soluble than the complex 1•Pt, which contains a shorter propyl chain. Their sensing behavior essentially arises by the quenching of Pt(II)-based intense luminescence due to the supramolecular charge transfer (CT) process originating from Pt(II)C ∧ N ∧ N-antenna to the electron deficient nitroaromatic explosives. Our present work shows that the micellar adducts formed by highly luminophoric material and surfactant molecules could effectively detect such explosives in aqueous medium with better sensitivity compared to what were observed in other media.

The effect of incorporating whey protein concentrate (WPC) on the quality characteristics of Mozzarella cheese analogue (MCA) based on rennet casein (RC) was studied. The proportion of RC:WPC tried out were 95:5, 90:10, and 85:15 w/w. The formulation of MCA comprised of 23.5% of blend of RC and WPC, 15% specialty vegetable fat, 2.75% trisodium citrate + disodium hydrogen orthophosphate (2.5:1, w/w), 0.07% calcium chloride, 0.6% citric acid, 1.1% NaCl, 1.5% cheese bud flavoring, and rest water. Varying the proportion of RC and WPC had a significant influence on the composition, textural properties, baking qualities and sensory quality of MCA judged as a topping on pizza pie. MCA made using protein blends (RC:WPC-90:10 or 85:15) behaved satisfactorily during pizza baking trials. However, looking at the superiority of MCA made using RC:WPC (90:10) with regard to shred quality and marginal superiority in terms of the total sensory score of cheese, judged as pizza topping, the former blend (i.e. RC:WPC, 90:10) was selected. The MCA obtained employing such protein blend had composition similar to that of Pizza cheese prepared from cheese milk and had requisite baking characteristics needed as a pizza topping. It is recommended to use a blend of RC and WPC (90:10) as the protein source in the formulation of MCA to obtain nutritionally superior cheese product having desired functional properties for its end use in baking applications.

Protracted diarrhea in neonates is uncommon and usually requires an intestinal biopsy for etiological diagnosis. Gastric biopsy has not been used in the routine diagnosis of this condition. We report the first documented patient with microvillous inclusion disease from India, where the diagnosis was established by a gastric biopsy.

Two-photon absorption (TPA) properties of a laterally nonsymmetric aza cryptand with attached side arms have been investigated. This series of Schiff base derivatives supports the mechanistic approach for enhancing the TPA process, which is usually dictated by molecular geometry, pi-bridging, delocalization length, and corresponding charge-transfer possibilities. The results described here suggest that on increasing the branching units, the TPA cross-section, sigma((2)), can be tuned to a larger value. The TPA activity is "switched on" when a metal atom enters the cavity and serves as a conduit of electronic delocalization. The sigma((2)) value increases as the donor strength increases. The maximum value is obtained on moving from the single-branched system to the nearly threefold symmetry. This serves as a useful synthetic strategy for designing novel octupolar molecules with high sigma((2)) values. Theoretical calculations at the B3LYP functional with the 6-31G* basis set under DFT formalism provide supporting evidence that the communication between the side arms through the metal d orbital and more ordered geometry of chromophores leads to a smaller HOMO-LUMO gap, which has a great influence upon the electronic properties of the molecules.

Objective: To document effects of intrapartum risk factors for early onset sepsis (EOS) on CRP levels in neonates and to assess the suitability of this test in diagnosing EOS., Design: Cohort study., Setting: Labour and post natal wards in a tertiary level teaching hospital in India., Subjects: 250 neonates at risk of developing infection., Methods: CRP levels in cord blood and neonatal blood at 24 hrs were estimated using commercial kits. Babies were observed for signs of sepsis for at least 48 hours., Results: Seven (2.8 Percent) neonates had elevated CRP levels in the cord blood. At 24 hours, 102 (40.8 Percent) babies had elevated levels. Elevated cord CRP levels was significantly associated with rupture of membranes for 24 hours (p =0.04), labour more than 12 hours (p = 0.002), and maternal fever (p = 0.01). At 24 hours, elevated CRP levels were associated with primiparity (p= 0.006), more than three vaginal examinations after membrane rupture (p=0.02), meconium staining of amniotic fluid (p =0.02) and amnioinfusion (p =0.02). Ten (4 Percent) babies developed EOS. The negative predictive value for elevated CRP levels at 24 h was 99 Percent., Conclusion: Several intrapartum risk factors for EOS can cause elevation in CRP levels. However, this test may be useful in excluding infection.

Acute fatty liver of pregnancy is an uncommon, potentially fatal disorder. Between 1998 and 2000, two patients with acute fatty liver of pregnancy presented at the Christian Medical College Hospital, Vellore. Both patients were in the thirty-sixth week of pregnancy. jaundice and encephalopathy were the predominant symptoms. Both the mothers died after they delivered a stillborn Infant each. The maternal deaths were due to multiorgan failure and/or postpartum haemorrhage and sepsis. The route of delivery was vaginal in both the patients. Extrahepatic and metabolic complications in both cases Included renal failure, sepsis, hypoglycaemia, disseminated intravascular coagulation and gastrointestinal bleeding. Liver biopsy done in both patients was consistent with the diagnosis of acute fatty liver of pregnancy. To the best of our knowledge, this is the first report from India on acute fatty liver of pregnancy.