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A leap‐forward approach has been successfully devised to synthesize a novel hierarchical binary metal modified heteroatom doped 2D micro‐/mesporous carbon‐graphene nanostructure (NPSMC@Ir−Ru@rGO) for overall water splitting application. To investigate the role of decorating metals, different electrolcatalysts like NPSMC, NPSMC@rGO, NPSMC@Ir@rGO, and NPSMC@Ru@rGO were also synthesized and structural changes were compared and investigated by physiochemical techniques. All of the samples have shown electrocatalytic activities attributed to the presence of heteroatom (N, P, S) doped micro‐/mesoporous carbonaceous matrix, amorphous carbon in the coexistence of graphitic lattice carbons, presence of active metal NPs (Ir and/‐or Ru), an even distribution of active sites, and graphene 2D interconnected channels to promote electron transfer ability, respectively. However, the Ir−Ru metal codeped nanocatalyst (NPCMS@Ir−Ru@rGO) is proved to be an excellent electrocatalyst based on the synergistic role of Ir−Ru metals that necessitates the low overpotentials of 181 mV and 318 mV to convey a current density of 10 mA cm−2 towards the electroctalytic application of HER and OER, respectively. Furthermore, exhibiting the corresponding Tafel slopes (132 and 70 mV dec−1) in an alkaline medium. This work is anticipated to open up new avenues for the development of promising electrocatalysts based on active metals modified heteroatom doped carbon nanomaterials for energy applications. [ABSTRACT FROM AUTHOR]

The mung bean [Vigna radiata (L.) Wilczek] grown in arid lands experiences yield losses due to the non-availability of water at pod filling and flowering stages which may be moderated by seed priming use of nanomaterials. The present study was based on the hypothesis that seed priming with zinc oxide nanoparticles (ZnO_NPs) can moderate the adverse effects of aridity on mung bean plants by improving crop performance in terms of growth, antioxidant defence, and yield. The hypothesis was tested in field trials in a split plot factorial design. The seed priming with 75 ppm ZnO_NPs improved the growth of water-stressed mung bean plants in terms of shoot length, root length, number of leaves, number of vegetative branches per plant, and number of reproductive branches per plant by 32%, 24%, 43%, 39%, and 30% respectively compared to control. Furthermore, the seed priming with 75 ppm ZnO_NPs caused the accumulation of osmolytes such as proline, total soluble sugars, and total soluble protein by 18%, 14%, and 81% respectively. The levels of malondialdehyde and hydrogen peroxide were depressed significantly and antioxidant defence functioning was improved by seed priming treatments with ZnO_NPs. The yield profile of water-stressed plants improved significantly in terms of pod length, number of grains per pod, number of pods per plant, seed yield, biological yield, and harvest index by 37%, 50%, 39%, 16%, 9%, and 6% respectively. The yield and production of mung bean plants can be improved through seed priming with ZnO_NPs when grown in arid lands. [ABSTRACT FROM AUTHOR]

Bitter gourd (Momordica charantia L.), grown in semi-arid and fragile soil, exhibits poor growth, yield loss, and reduced quantity of bioactive compounds which may be improved by seed priming with bio-rationale materials. A field experiment was undertaken from March to June 2022 to determine the efficacy of zinc oxide nanoparticles (ZnONPs) on bitter gourd growth, yield, and some phytochemical contents through seed priming. Plants of bitter gourd were divided into five sets. The first set served as a control and was not treated with ZnONPs. The plants of sets 2, 3, 4, and 5 were treated with ZnONPs primed seed at 0.5, 0.10, 0.15, or 0.20 mL∙L−1 concentrations, and priming duration of 24 h. Seed priming with 0.20 mL∙L−1 improved vine length, number of leaves, and number of branches per plant by 46, 21, and 39% compared to the control. Days to plant emergence and flowering were reduced and yield attributes improved by seed priming. Total phenolic, total flavonoids, and charantin, a steroidal saponin, contents as major secondary metabolite of fresh fruit of bitter gourd improved by 47, 36, and 52% treated with 0.20 mL∙L−1 of ZnONPs primed seed. Seed priming with ZnONPs could be used to improve growth, germination, important metabolites and yield of bitter gourd. [ABSTRACT FROM AUTHOR]

Fluorescent nanoprobes are highly desirable toolkit for bioimaging applications. This study reports the first example for the synthesis of a nontoxic prototypical fluorescent organic compound 2‐benzo[d]thiazol‐2‐yl)‐3‐(2‐chloro‐4‐(dimethylamino)phenyl)acrylonitrile (BCA) and its entrapment into the poly[cyclotriphosphazene‐co‐polyethyleneimine] cross‐linked (PCPEI) nanospheres named as BCA@PCPEI for targeted cell imaging application. The as‐prepared BCA@PCPEI nanospheres were thoroughly characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), fourier transform infrared (FTIR), thermogravimetric analysis (TGA), and phosphorus‐31 nuclear magnetic resonance (31P‐NMR) analyses. The surface functional analysis of the nanospheres was performed by X‐ray photoelectron spectroscopy (XPS), which proves that the content ratios of elements belong to the precursors concentrations. The as‐prepared nanospheres displayed emission at 606 nm with bright orange fluorescence at any concentration. Moreover, the nanospheres were also less cytotoxic and maintained remarkable cell viability up to 100 μg/mL. Owing to the fluorescence with higher emission, this material has shown excellent cell imaging performance with better targeting ability to HeLa cells. [ABSTRACT FROM AUTHOR]

The properties of ethylenepropylenediene monomer (EPDM) insulations are often inadequate for solid rocket motor (SRM) applications. These materials exhibit relatively high erosion rates during the operation of SRM unless they are reinforced with suitable fiber fillers. In this article, we report the findings of comprehensive mechanical and ablative studies of EPDM insulations blended with polyacrylonitrile (PAN) fiber, pre‐oxidized polyacrylonitrile fiber and carbon fiber using a two‐roll mill methodology. During the course of this investigation, PAN fiber‐filled EPDM insulations showed much superior mechanical and ablative properties than other fiber‐filled EPDM insulations. The microstructures of charred layers of these insulations after ablation were characterized by scanning electron microscopy. POLYM. COMPOS., 39:3336–3340, 2018. © 2017 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Macroscopic supramolecular assembly plays a key role to bridge the fundamental researches on molecular recognition to the potential applications as supramolecular materials. However, the challenge remains to promote the research from soft hydrogel system to semirigid objects or building blocks. Herein, the concept of flexible spacing coating was employed to modify the model polydimethylsiloxane building blocks, and reversible macroscopic assembly was successfully realized through introducing highly directional, dynamic, and reversible coordinate interactions as driving forces. The driving force for the macroscopic assembly was confirmed by introducing highly competitive ethylene diamine tetra acetic acid solution as an orthodox system to disassemble the assembled blocks. Moreover, the coordinate interaction was further understood through unique in situ measurements of binding forces between building blocks during assembly process. This work of macroscopic supramolecular assembly provides an in situ visible platform, which is significant to clarify the highly fascinating and facile coordinate interactions on the macroscopic assembly behavior. [ABSTRACT FROM AUTHOR]

The main objective of this research was to conduct a theoretical investigation into the antioxidant properties of chlorogenic acid. Calculations based on the density functional theory were performed using the B3LYP exchange-correlation functional and the 6-311G standard basis set to determine the theoretical parameters, such as bond dissociation enthalpy and spin density. H atom abstraction from −OH groups was the most representative reaction pathway chosen for this study. From these calculations, it was estimated that bond dissociation enthalpies of hydroxyl groups were in the order of 3’-OH > 4’-OH > 2-OH > 1-OH. Spin densities of O-atoms of free radicals formed (after the removal of H atoms) from the hydroxyl groups of aromatic rings were lower than that of hydroxyl groups of alicyclic rings. On the basis of the calculated results, H atom abstraction from −OH groups of aromatic ring should be the main mechanism for the antioxidant potential of chlorogenic acid. Moreover, a comparison of bond dissociation enthalpy values for different phenolic acid antioxidants showed that the chlorogenic acid is a potent antioxidant. This theoretical investigation might be helpful for the future applications of chlorogenic acid in the field of the pharmacy and food industries. [ABSTRACT FROM PUBLISHER]

Coconut carbon was activated by various concentrations of KOH to obtain carbon with different surface area and porosity, hence co-relate the effects of activation on surface area, pore size, and desalination performances of resulted activated carbons. For activation purpose, 0.05, 0.1, 0.2, and 0.5 M KOH solutions were used, subsequently followed by carbonization under N2atmosphere. The resulted surface areas were found to be 909.21, 703.47, 647.32, and 601.14 m2 g−1, respectively. Activated carbon electrodes were prepared with poly tetrafluoroethylene and carbon black, tested for electrosorption of NaCl under 1.6 V. Highest adsorption values were found to be 21, 15, 16, and 26 mg L−1 g−1for 0.05, 0.1, 0.2, and 0.5 M KOH Ac. Brunauer–Emmett–Teller and scanning electron microscopy confirmed the electrodes were porous, and the average pore size was in the range of 2.46–2.81 nm. Furthermore, Fourier transforms infrared spectroscopy spectra were used to investigate the presence of oxygen containing functional groups. The electrical double layer formation was characterized by using cyclic voltammetry. [ABSTRACT FROM PUBLISHER]

The layer-by-layer (LbL) technique has been intensively investigated as a straightforward method for the incorporation of drug molecules or other bioactive species, enabling retarded release in drug delivery devices, in bioactive interfaces, in tissue engineering, and in regenerative medicine. The preparation of crosslinked LbL multilayers with embedded drug reservoirs for delayed release remains a challenging task, however. In the present study we have developed a method for the simultaneous utilisation of covalent interlayer linkages and drug reservoirs that can hold model drug molecules. A strategy of post-infiltration of photoactive bifunctional small molecules followed by UV irradiation has been employed for crosslinking the LbL multilayers, incorporating poly(amido amine) (PAMAM) molecules, which serve as a drug reservoir. The covalent linkage significantly alters the release profile of the model drug from the multilayers, with retarded release of hydrophobic molecules from a solvent, and enabling the loaded multilayers to withstand rinsing with 75% ethanol, the most commonly used sterilization procedure. [ABSTRACT FROM AUTHOR]

The 3,3′,5,5′-tetramethylbenzidine-H 2 O 2 (TMB-H 2 O 2) platform has gained widespread use for rapid detection of various analytes in foods. However, the existing TMB-H 2 O 2 platforms suffer from limited accuracy, as their signal output is confined to the visible region, which is prone to interference from various food colorants in real samples. To address this challenge, a novel Au@Os-mediated TMB-H 2 O 2 platform is developed for both rapid and accurate detection of analytes in foods. The prepared Au@Os NPs exhibit remarkable peroxidase-like activity, making the platform display dual absorption peaks in visible and near-infrared (NIR) regions, respectively. This Au@Os-mediated TMB-H 2 O 2 platform exhibited three linear ranges across different concentrations of ziram from 1–100, 150–600, and 800–2000 nM with limit of detection (LOD) 7.9 nM and limit of quantification (LOQ) 24.15 nM respectively. Further, the Au@Os-mediated TMB-H 2 O 2 platform was also used for rapid and accurate detection of ziram in real food samples like apple, tomato, and black tea. • Synthesis of a novel Au@Os core-shell NPs with excellent peroxidase-like activity. • Au@Os mediated TMB-H 2 O 2 sensing platform with Vis and NIR absorption signal-output. • Rapid and accurate detection of ziram in real foods. • Improved sensitivity for ziram detection with LOD of 7.9 nM and LOQ of 24.15 nM. [ABSTRACT FROM AUTHOR]

This research describes the synthesis of a novel type of poly [cyclotriphosphazene-co-1,3,5-triol nitrobenzene] (PCTNB) microspheres with uniform size and diameter of more than 2 μm having well characterization. These microspheres are further used to wrap the CNTs by a facile route using template based non-covalent method to form PCTNB@CNTs composite. This composite is further well analyzed before it is subjected to pyrolysis. The direct carbonization of the PCTNB@CNTs is performed at 600 °C at a rate of 5 °C/min under N 2 atmosphere to render the N, P, O doped carbonized PCTNB@CNTs having enhanced electronic features to be applied as an ORR electrocatalysts in fuel cells accompanied by TEM, XPS, Raman, FT-IR, TGA and BET analyses. Here, we have designed a metal-free, N, P, O doped (C-PCTNB@CNTs) electro-catalyst which exhibit significantly high ORR performance in acidic PEM cells showing much higher onset potential of (0.94 V) and half-wave potential of (0.85 V) with electron transfer number ( n ) 3.9 at 0.4–0.7 V as compared to other non-metallic electro-catalysts. Thus, (C-PCTNB@CNTs) is a metal-free, methanol tolerant carbon-based ORR catalyst, and it opens up new avenues for clean energy generation for affordable and durable fuel cells. [ABSTRACT FROM AUTHOR]