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This paper addresses the problem of tracking a high-speed ballistic target in real time. Particle swarm optimization (PSO) can be a solution to overcome the motion of the ballistic target and the nonlinearity of the measurement model. However, in general, particle swarm optimization requires a great deal of computation time, so it is difficult to apply to realtime systems. In this paper, we propose a parallelized particle swarm optimization technique using field-programmable gate array (FPGA) to be accelerated for realtime ballistic target tracking. The realtime performance of the proposed method has been tested and analyzed on a well-known heterogeneous processing system with a field-programmable gate array. The proposed parallelized particle swarm optimization was successfully conducted on the heterogeneous processing system and produced similar tracking results. Also, compared to conventional particle swarm optimization, which is based on the only central processing unit, the computation time is significantly reduced by up to 3.89×. [ABSTRACT FROM AUTHOR]

The electrocatalytic reduction of nitrate waste into ammonia allows both the removal of nitrate contaminants and an alternative production of ammonia compared to the classical Haber–Bosch industrial process. Ammonia is useful in agriculture for manufacturing fertilizers, and as a reagent in pharmaceuticals, metallurgy, explosives, and the textile industry; ammonia is also an energy carrier in the automobile industry for next-generation fuel cells. Here we review the nitrate-to-ammonia conversion by electrocatalysis of industrial and agricultural waste, with focus on catalysts, reaction intermediates, side reactions, and reaction conditions. Electron transfer is facilitated by electrocatalysts with transition metals having occupied d-orbitals with similar energy levels to that of the nitrate lowest unoccupied molecular orbital. Green electro-conversion using carbon-based materials is also discussed. Results show nitrate conversion from 53 to 99.8% and ammonia selectivity from 70 to 97.4%. [ABSTRACT FROM AUTHOR]

In this paper, we present a novel dimensionality reduction term (i.e. TripletPCA and ContrastivePCA) designed to enhance the robustness of pair-based loss functions in metric learning against image corruptions. Notably, our approach achieves this without the need for any data preprocessing steps. Our method can be seamlessly integrated into existing models, such as a block with Plug & Play framework. To the best of our knowledge, our TripletPCA and ContrastivePCA represent the first attempts to incorporate dimensionality reduction directly into pair-based metric learning losses for end-to-end metric learning. By projecting image features into low-dimensional vectors, our proposed loss functions effectively retain the essential components of images while mitigating the impact of corrupted features. Consequently, our metric learning loss function accurately computes feature distances through the projection. Experimental results demonstrate that our dimensionality reduction term can be easily incorporated into various types of existing deep neural networks. This integration leads to a substantial improvement in performance on standard benchmark datasets for corrupted image classification tasks. On several corruption datasets, we achieve an average performance improvement of 10.55% compared to existing baseline methods. Our code is available at https://github.com/Juryun/TDRL. [ABSTRACT FROM AUTHOR]

• Free-standing acoustic levitator technique for organic dye self-aggregation process. • Methylene blue (MB) droplet aggregation via acoustic standing waves. • MB dimerization reactions monitored by in situ spectroscopic techniques. • H- and J-aggregation in different solvent environments was studied by DFT studies. In this work, we explored the in-situ reaction modeling of the molecular self-aggregation of methylene blue (MB), which is a cationic thiazine dye, in different solvents via a container-less acoustic levitator by floating of a single droplet. Our in-situ spectroscopic study revealed that the dimer essentially has a sandwich structural geometry with a deviation from parallel stacking and horizontal arrangements in the molecular planes. The real time conversion of the monomer in MB into a dimer and their dynamics in water and ethanol media were monitored using a free-standing acoustic levitator droplet system. The absorption spectra revealed changes in the two resolved peaks (monomer and dimer) and orderliness when water and ethanol were used as the media. Interestingly, the enhancement in the dimerization of MB could be attributed to droplet evaporation, which is difficult to observe in typical reactor containers. Moreover, acidic protonation resulted in a change in the aggregation orientation direction of the MB molecules, forming an unusual J-aggregation. Theoretical DFT calculations revealed that MB underwent typical H-aggregation and J-aggregation in the different solvent environments, and their orientations well matched the spectroscopic data. [ABSTRACT FROM AUTHOR]

A nondestructive testing device, consisting of a scanner and signal processing circuits was developed to detect cracks in turbine disk roots. The scanner consists of a longitudinal feeder and a fir-tree-shaped sensor probe. The feeder inserted the sensor probe along the grooves of the turbine blade attachment. Meanwhile, permanent magnets were placed in opposite direction, to generate a closed magnetic field between the magnetic sensors located on the crests of the sensor probe. The fatigue crack in the turbine disk root occurred in the circumferential direction of the turbine. As a result, magnetic flux leakage was caused by disturbing the flow of closed magnetic field by permanent magnets. The magnetic flux leakage was measured by a magnetic sensor. The effectiveness of the proposed device has been verified using artificial defects introduced into the turbine disk roots by electric discharge machining. [ABSTRACT FROM AUTHOR]

[Cs+(Cryptand[2.2.2])]I− (1; Cryptand[2.2.2] = C222) was characterized via single‐crystal X‐ray diffraction and was shown to crystallize in the monoclinic space group I2/c system with a = 8.9605 (2), b = 23.5073 (5), c = 11.7563 (3) Å, and β = 93.792 (2)°. Stationary and magic angle spinning (MAS) experiments under different magnetic fields allowed for the separation of the chemical shift and quadrupole coupling tensor parameters. Remarkably, MAS spectra showing pure second‐order quadrupole powder patterns at 4.23 T were observed for 133Cs nuclei with small quadrupole moments owing to the large electric field gradients (EFGs) caused by short CsO and CsN bond distances in the [Cs+(C222)] ions. Stationary NMR powder patterns with a combination of the chemical shifts and second‐order quadrupolar interactions were observed. The EFG and chemical shift tensor components calculated using the atomic coordinate files and Gaussian 09 were reasonably consistent with the experimental values. [ABSTRACT FROM AUTHOR]

C24H18N4O4, monoclinic, P21/c (no. 14), a = 16.5930(5) Å, b = 5.7298(2) Å, c = 20.8714(6) Å, β = 99.8620(10)°, V = 1955.02(11) Å3, Z = 4, Rgt(F) = 0.0415, wRref(F2) = 0.1115, T = 193 K. [ABSTRACT FROM AUTHOR]

Establishing appropriate heatwave thresholds is important in reducing adverse human health consequences as it enables a more effective heatwave warning system and response plan. This paper defined such thresholds by focusing on the non-linear relationship between heatwave outcomes and meteorological variables as part of an inductive approach. Daily data on emergency department visitors who were diagnosed with heat illnesses and information on 19 meteorological variables were obtained for the years 2011 to 2016 from relevant government agencies. A Multivariate Adaptive Regression Splines (MARS) analysis was performed to explore points (referred to as “knots”) where the behaviour of the variables rapidly changed. For all emergency department visitors, two thresholds (a maximum daily temperature ≥ 32.58°C for 2 consecutive days and a heat index ≥ 79.64) were selected based on the dramatic rise of morbidity at these points. Nonetheless, visitors, who included children and outside workers diagnosed in the early summer season, were reported as being sensitive to heatwaves at lower thresholds. The average daytime temperature (from noon to 6 PM) was determined to represent an alternative threshold for heatwaves. The findings have implications for exploring complex heatwave-morbidity relationships and for developing appropriate intervention strategies to prevent and mitigate the health impact of heatwaves. [ABSTRACT FROM AUTHOR]

Abstract: Pentamethylcyclopentadienyl (Cp*)‐based Group 9 metal (Co, Rh, or Ir) catalysts have emerged as powerful tools for C−H functionalization reactions. Whilst a diverse range of organic transformations have been developed by using [Cp*MIII] catalysts, they have often exhibited orthogonal reactivities and varied selectivities that depended on the choice of the central metal atom. An understanding of the physicochemical properties of the metals, as well as of their reaction mechanisms, has led to significant expansion of the synthetic scope of C−H functionalization reactions. This Focus Review summarizes and discusses the comparative catalytic reactivities and selectivities of the [Cp*MIII] catalysts, with an emphasis on metal‐dependent pathway‐switching by considering the mechanistic rationale. [ABSTRACT FROM AUTHOR]

[Display omitted] • Acoustic levitation coupled with pulsed laser irradiation process. • Free-standing nanocatalysts synthesis via hybrid acoustic levitation/PLI process. • Au NPs showed excellent catalytic behavior towards 4-nitrophenol reduction. • Formation of NPs and chemical reactions monitored by in situ spectroscopic techniques. Acoustic levitation is a distinctive and versatile tool for levitating and processing free-standing single droplets and particles. Liquid droplets suspended in an acoustic standing wave provide container-free environments for understanding chemical reactions by avoiding boundary effects and solid surfaces. We attempted to use this strategy for the production of well-dispersed uniform catalytic nanomaterials in an ultraclean confined area without the addition of external reducing agents or surfactants. In this study, we report on the synthesis of gold and silver nanoparticles (NPs) via acoustic levitation coupled with pulsed laser irradiation (PLI). In situ UV–Visible and Raman spectroscopic techniques were performed to monitor the formation and growth of gold and silver NPs. The PLI was used for the photoreduction of targeted metal ions present in the levitated droplets to generate metal NPs. Additionally, the cavitation effect and bubble movement accelerate the nucleation and decrease the size of NPs. The synthesized Au NPs with ∼ 5 nm size showed excellent catalytic behavior towards the conversion of 4-nitrophenol to 4-aminophenol. This study may open a new door for synthesizing various functional nanocatalysts and for achieving new chemical reactions in suspended droplets. [ABSTRACT FROM AUTHOR]

Polyaminobenzenes were synthesized by the ruthenium-catalyzed iterative C−H amidation of anilides using dioxazolones as an amino source. This strategy could be implemented by the sequential activation of C−H bonds of formerly generated compounds by cascade chelation assistance of newly installed amide groups. Computational studies provided a rationale. [ABSTRACT FROM AUTHOR]

Polyaminobenzenes were synthesized by the ruthenium-catalyzed iterative C−H amidation of anilides using dioxazolones as an amino source. This strategy could be implemented by the sequential activation of C−H bonds of formerly generated compounds by cascade chelation assistance of newly installed amide groups. Computational studies provided a rationale. [ABSTRACT FROM AUTHOR]

A procedure for the [Cp*CoIII]-catalyzed direct C-H amidation of arenes with dioxazolone has been developed. This reaction proceeds under straightforward and mild conditions with a broad range of substrates, including anilides. A comparative study on the catalytic activity of Group 9 [{Cp*MCl2}2] complexes revealed the unique efficiency of the cobalt catalyst. [ABSTRACT FROM AUTHOR]

A procedure for the [Cp*CoIII]-catalyzed direct C-H amidation of arenes with dioxazolone has been developed. This reaction proceeds under straightforward and mild conditions with a broad range of substrates, including anilides. A comparative study on the catalytic activity of Group 9 [{Cp*MCl2}2] complexes revealed the unique efficiency of the cobalt catalyst. [ABSTRACT FROM AUTHOR]

The decrease in fossil fuel usage and the projected 28% increase in the global energy demand by 2040 are calling for advanced methods to convert modern biomass into fine chemicals. For instance, biomass-derived aldehydes appear as promising substitutes for the chemical and fuel industries. Here, we review electrochemical upgrading of furfural and 5-hydroxymethylfurfural with a focus on catalysis and selectivity mechanisms. We also present hybrid water electrolysis systems for production of hydrogen and chemicals. We discuss electrochemical oxidation or hydrogenation of furfural and 5-hydroxymethylfurfural using metal oxides, noble metals, transition metal nanoparticles and alloys, and nonoxides. We compare electrochemical processes with combustion, chemical, thermochemical, and biochemical processes for biomass conversion. [ABSTRACT FROM AUTHOR]

The B(C6F5)3-catalyzed silylative reduction of conjugated nitriles has been developed to afford synthetically valuable β-silyl amines. The reaction is chemoselective and proceeds under mild conditions. Mechanistic elucidation indicates that it proceeds by rapid double hydrosilylation of the conjugated nitrile to an enamine intermediate which is subsequently reduced to the β-silyl amine, thus forming a new C(sp3)Si bond. Based on this mechanistic understanding, a preparative route to enamines was also established using bulky silanes. [ABSTRACT FROM AUTHOR]

The B(C6F5)3-catalyzed silylative reduction of conjugated nitriles has been developed to afford synthetically valuable β-silyl amines. The reaction is chemoselective and proceeds under mild conditions. Mechanistic elucidation indicates that it proceeds by rapid double hydrosilylation of the conjugated nitrile to an enamine intermediate which is subsequently reduced to the β-silyl amine, thus forming a new C(sp3)Si bond. Based on this mechanistic understanding, a preparative route to enamines was also established using bulky silanes. [ABSTRACT FROM AUTHOR]

A new synthetic routeto phosphoramidates by intermolecular C–Hamidation is presented. Substrates with assorted directing groupswere activated by an iridium-based catalyst system and reacted witha number of phosphoryl azides, executing efficient phosphoramidatesynthesis via C–N bond formations. [ABSTRACT FROM AUTHOR]

Herein, we fabricated a more sensitive nonenzymatic electrochemical sensor for the selective determination of hydroquinone as a targeted pollutant at zinc@zinc oxide (Zn@ZnO) core-shell nanostructures. The nanostructured Zn@ZnO materials were produced using pulsed laser ablation in an aqueous medium without the use of any reducing agents or surfactants. The detailed structural, morphological, elemental composition, and electrochemical voltammetric analyses revealed a significant improvement in Zn@ZnO performance for selective hydroquinone detection. A broad linear calibration response was obtained as 10–90 μM with high sensitivity of 0.5673 μA μM−1 cm−2 and the low detection limit was 0.10443 μM for detection of hydroquinone. The modified Zn@ZnO electrode's excellent electrochemical sensing performance was attributed to the accessibility of a high electrochemically active surface area (EASA = 0.00345 μF/cm2) and an improved electron transfer rate. Stability and antiinterference tests were also carried out. A 100 fold increase in the concentration of common cations and anions (Na+, Mg2+, Cl−, SO 4 2−, and NO 3 −) did not affect the selective determination of HQ. As a result, the fabricated electrochemical sensor has a wide range of potential applications in environmental and biomedical science. • Zn@ZnO core shell was prepared by pulsed laser ablation method. • Zn@ZnO based electrochemical sensor was developed for hydroquinone detection. • Fabricated sensor exhibits high sensitivity with LOD of 0.10 μM in 10–90 μM range. • Excellent selectivity and stability were observed from Zn@ZnO towards HQ. [ABSTRACT FROM AUTHOR]

Highlights: [•] A new series of highly efficient Ir(III) complexes were synthesized. [•] We fabricated solution processable PhOLEDs using graphene oxide as a hole transport layer. [•] Ir(III) complexes show good thermal stability and good chemical compatibility with the host. [•] Maximum luminance efficiency of 26.9cd/A and an external quantum efficiency of 14.2% were achieved. [ABSTRACT FROM AUTHOR]

Abstract: Three Y-shape organic dyes, (Z)-3-(5-(3,5-bis(4-(9H-carbazol-9-yl)styryl)-4-methoxyphenyl)thiophen-2-yl)-2-cyanoacrylic acid (OD-1), (Z)-3-(5′-(3,5-bis(4-(9H-carbazol-9-yl)styryl)-4-methoxyphenyl)-2,2′-bithiophen-5-yl)-2-cyanoacrylic acid (OD-2) and (Z)-3-(5′-(3,5-bis(4-(9H-carbazol-9-yl)styryl)-4-methoxyphenyl)-3,4′-4″-trithiophenyl-5-yl)-2-cyanoacrylic acid (OD-3) were synthesized and used as sensitizers in nanocrystalline dye-sensitized solar cells (DSSCs). The introduction of the bis(carbazolylstyryl) units as an electron donor group and oligothiophene units as a both electron donors and π-spacers increased the conjugation length of the sensitizers and thus improved their molar absorption coefficient and light harvesting efficiency. DSSCs with the configuration of SnO2:F/TiO2/organic dye/liquid electrolyte/Pt devices were fabricated using these OD-1, OD-2 and OD-3 as a sensitizers. Among the devices, the DSSC composed of OD-3 exhibited highest power conversion efficiency of 3.03% under AM1.5G (100 mW cm−2). [Copyright &y& Elsevier]

Abstract: We fabricated highly efficient solution processed red phosphorescent organic light-emitting diodes (PhOLEDs) composed of bis[9-ethyl-3-(4-phenylquinolin-2-yl)-9H-carbazolato-N,C 2′]iridium picolinate N-oxide (Et-CVz-PhQ)2Ir(pic-N-O) and bis[9-(2-(2-methoxyethoxy)ethyl)-3-(4-phenylquinolin-2-yl)-9H-carbazolato-N,C 2′]iridium picolinate N-oxide (EO-CVz-PhQ)2Ir(pic-N-O) as an emitter, which were doped into poly(N-vinylcarbazole) (PVK), electron transport material, 1,3-bis[2-(4-tert-butylphenyl)-1,3,4-oxadiazo-5-yl]benzene (OXD-7) and optimized concentration of hole transport material, N,N′-diphenyl-N,N′-(bis(3-methylphenyl)-[1,1-biphenyl]-4,4′-diamine (TPD). The optimized PhOLEDs doped with 16wt% of TPD shows a maximum external quantum efficiency of 9.21% and a luminance efficiency of 15.24cd/A with a CIE coordinate of (0.62,0.38). [Copyright &y& Elsevier]

Anthocyanin accumulation is responsible for the coloration of apple fruit, and their accumulation depends on the expression of anthocyanin biosynthesis-related genes. Light is an environmental stimulus that induces fruit color by regulating genes involved in the anthocyanin biosynthesis pathway. In this study, the roles of light and genetic factors on fruit coloration and anthocyanin accumulation in apple fruit were investigated. Three genes in the anthocyanin biosynthesis pathway, MdCHS, MdANS, and MdUFGT1, were synthesized and cloned into a viral-based expression vector system for transient expression in 'Ruby S' apple fruits. Apple fruits were agroinfiltrated with expression vectors harboring MdCHS, MdANS, and MdUFGT1. Agroinfiltrated apple fruits were then either kept in the dark (bagged fruits) or exposed to light (exposed fruits). The agroinfiltrated fruits showed significantly different coloration patterns, transcript expression levels, and anthocyanin accumulation compared to the control fruits. Moreover, these parameters were higher in exposed fruits than in bagged fruits. For stable expression, MdCHS was introduced into a binary vector under the control of the rice α-amylase 3D (RAmy3D) promoter. The ectopic overexpression of MdCHS in transgenic rice calli showed a high accumulation of anthocyanin content. Taken together, our findings suggest that light, together with the overexpression of anthocyanin biosynthesis genes, induced the coloration and accumulation of anthocyanin content in apple fruits by upregulating the expression of the genes involved in the anthocyanin biosynthesis pathway. [ABSTRACT FROM AUTHOR]

Apple skin color is essential for market value. Therefore, this study evaluated the efficiency of pneumatic defoliation (PD) on the enhancement of red skin color and anthocyanin pigments in 'Picnic' apples. Three weeks before harvesting, apple trees were treated with PD with low- (0.7 bar) and high- (0.9 bar) air pressure at a tractor driving speed of 2 km/h. Undefoliated trees served as controls. Higher leaf defoliation and leaf damage rates were observed in the high-PD treatment than those in the low-PD treatment. Photosynthetically active radiation inside the canopies was the highest in trees subjected to high-pressure PD than in those that underwent low-pressure PD and the controls. At harvest, the fruit color (a*) value, red-colored area, and anthocyanin content in the fruit skin were the highest in the high-PD treatment, intermediate in the low-PD treatment, and the lowest in the control treatments. Additionally, a higher expression of anthocyanin biosynthetic genes was observed in both defoliation treatments, especially under high PD. However, except for higher flesh firmness under low PD, the L* and b* values and fruit quality indices (fruit weight, starch pattern index, titratable acidity, soluble solids content, and sunburn occurrence) were not significantly affected by either PD treatment. In conclusion, PD can be used to enhance skin coloration and anthocyanin pigments in apples; further PD with high air pressure achieved optimum red skin coloration in 'Picnic' apples. [ABSTRACT FROM AUTHOR]

A straightforward protocol towards biologically important 7-aminoindoles is developed. [ABSTRACT FROM AUTHOR]

An abstract of the article "Comparative Catalytic Activity of Group 9 [Cp*MIII] Complexes: Cobalt-Catalyzed C-H Amidation of Arenes with Dioxazolones as Amidating Reagents" by Park J and Chang S. is presented.

In the presence of excess diphenyl and triphenyl silane acryl nitriles are reduced to silyl amines and N-disilyl enamines. [ABSTRACT FROM AUTHOR]

Flowering time (in rice, termed the heading date), plant height, and grain number are crucial agronomic traits for rice productivity. The heading date is controlled via environmental factors (day length and temperature) and genetic factors (floral genes). TERMINAL FLOWER 1 (TFL1) encodes a protein that controls meristem identity and participates in regulating flowering. In this study, a transgenic approach was used to promote the heading date in rice. We isolated and cloned apple MdTFL1 for early flowering in rice. Transgenic rice plants with antisense MdTFL1 showed an early heading date compared with wild-type plants. A gene expression analysis suggested that introducing MdTFL1 upregulated multiple endogenous floral meristem identity genes, including the (early) heading date gene family FLOWERING LOCUS T and MADS-box transcription factors, thereby shortening vegetable development. Antisense MdTFL1 also produced a wide range of phenotypic changes, including a change in overall plant organelles that affected an array of traits, especially grain productivity. The transgenic rice exhibited a semi-draft phenotype, increased leaf inclination angle, restricted flag leaf length, reduced spikelet fertility, and fewer grains per panicle. MdTFL1 plays a central role in regulating flowering and in various physiological aspects. These findings emphasize the role of TFL1 in regulating flowering in shortened breeding and expanding its function to produce plants with semi-draft phenotypes. [ABSTRACT FROM AUTHOR]

The structural information of 3‐cyanoindole ammonia cluster, 3CI(NH3)1, in molecular beams was investigated in the gas phase. We obtained UV–UV hole‐burning spectrum (UV–UV HB) to determine the number of conformers present in the molecular beams and examine their spectral features. As a result, single conformer of 3CI(NH3)1 was observed in the mass‐selected one‐color resonant two‐photon ionization (1C‐R2PI) spectroscopy. The origin band of 3CI(NH3)1 in the R2PI spectrum is redshifted by 122 and 71 cm−1 compared to those of the 3CI monomer and 3CI 1:1 water cluster, 3CI(H2O)1, respectively. The fully optimized geometries, relative energies, transition energies, binding energies, and electrostatic potential (ESP) of the 3CI monomer, 3CI(H2O)1, and 3CI(NH3)1 clusters were calculated at the B3LYP and TD‐B3LYP methods with the 6‐311++(d,p) basis set. The observed spectra are compared with the predictions of time‐dependent density functional theory calculations. [ABSTRACT FROM AUTHOR]

Keymechanistic features of the [Cp*MCl2]2(M =Ir, Rh, Co; all are in group 9) catalyzed C–H aminationof benzamides with organic azides were investigated with a strongemphasis on the metal effects on thereactionmechanism, revealing that the Rh- and Ir-catalyzedreactions follow a similar reaction profile, albeit with differentindividual kinetic and thermodynamic parameters. The observation thatthe Ir-based system was much superior in terms of the rates and efficiencyin comparison to Rh was attributed to the intrinsically strongrelativistic effects in iridium.While a cobalt system [Cp*CoIII] showed littlecatalytic activity formost azides examined, plausible [(BA)(Cp*)CoNR]+intermediatesof these reactions were characterized as a “Co(III)-nitrenoidradical” species with a weak (“one electron–twocenter type”) Co–NPh bond. Its Rh and Ir analogues arecharacterized as diamagnetic metal nitrenoids with a strong MNRdouble bond. The provided experimental and computational investigationsindicate that the rate-limiting step of the reaction resides in thefinal stage (protodemetalation) that takes place via a concerted metalation–deprotonation(CMD) mechanism. While experimental measurements of thermodynamicparameters were in good agreement with DFT calculations, theoreticalpredictions on the electronic nature of key intermediates and energybarriers were successfully used to rationalize the experimentallyobserved reactivity pattern. [ABSTRACT FROM AUTHOR]

Two kinds of low-band gap polymers, poly[{N-(1-octyldecyl)-2,7-carbazole)}-alt-{1,7- di(4-tert-butylphenyloxy)-3,4,9,10-perylenebis(dicarboximide)-N,N′-di(2,6-dimethyl- phenyl-4-yl)}] poly(Cvz-PDIMEP) and poly{[N,N′-di(10-nonadecyl)perylene-3,4,9, 10-tetracarboxylic acid diimide-1,7-diyl]-alt-(9-heptadecyl)-9H-carbazol-2-yl)} poly (Cvz-PDIC9), were synthesized by palladium-catalyzed Suzuki polymerization. Bulk heterojunction solar cells with an ITO/PEDOT/polymer:PC71BM/LiF/Al configuration were fabricated, which shows short-circuit current density, open-circuit voltage, fill factor, and power conversion efficiency of 0.85 mA/cm2, 0.32 V, 0.27, and 0.073% under AM 1.5 irradiation (100 mW/cm2), respectively. [ABSTRACT FROM PUBLISHER]

The synthesis of bilayer heterojunctions has received considerable attention recently. Fabrication of novel bilayer composites is of significant interest to improve their photocatalytic efficiency. In this study, molybdenum disulfide (MoS 2), a layered dichalcogenide material exhibiting unique properties, in combination with graphitic carbon nitride (g-C 3 N 4), a carbon-based layered material, was fabricated with small amounts of zinc oxide (ZnO). Three composites, MoS 2 /g-C 3 N 4 , MoS 2 /ZnO, and MoS 2 /g-C 3 N 4 /ZnO were prepared via a simple exfoliation method and characterized by various physicochemical methods. The Z-scheme charge transfer mechanism in the prepared ternary composite improves efficiency by inhibiting the recombination rate of electron-hole pairs. It has shown excellent performance in degrading a major water contaminant, malachite green (MG) dye, under visible light irradiation. [ABSTRACT FROM AUTHOR]

Silylative reduction of nitriles is performed under transition metal-free conditions by using B(C6F5)3 as a catalyst with hydrosilanes as a reductant. [ABSTRACT FROM AUTHOR]

Dual-functional photo (electro)catalysis (PEC) is a key strategy for removing coexisting heavy metals and phenolic compounds from wastewater treatment systems. To design a PEC cell, it is crucial to use chemically stable and cost-effective bifunctional photocatalysts. The present study shows that ruthenium metallic nanoparticles decorated with CoFe 2 O 4 /RGO (Ru–CoFe 2 O 4 /RGO) are effective bifunctional photoelectrodes for the reduction of Cr(VI) ions. Ru–CoFe 2 O 4 /RGO achieves a maximum Cr(VI) reduction rate of 99% at 30 min under visible light irradiation, which is much higher than previously reported catalysts. Moreover, PEC Cr(VI) reduction rate is also tuned by adding varying concentration of phenol. A mechanism for the concurrent removal of Cr(VI) and phenol has been revealed over a bifunctional Ru–CoFe 2 O 4 /RGO catalyst. A number of key conclusions emerged from this study, demonstrating the dual role of phenol during Cr(VI) reduction by PEC. Anodic oxidation of phenol produces the enormous H+ ion, which appears to be a key component of Cr(VI) reduction. Additionally, phenolic molecules serve as hole (h+) scavengers that reduce e−/h+ recombination, thus enhancing the reduction rate of Cr(VI). Therefore, the Ru–CoFe 2 O 4 /RGO photoelectrode exhibits a promising capability of reducing both heavy metals and phenolic compounds simultaneously in wastewater. [Display omitted] • Ru–CoFe 2 O 4 /RGO bifunctional photoelectrode was fabricated for PEC reduction of Cr(VI). • A complete reduction of Cr(VI) was obtained at 0.8 V over 30 min under solar illumination. • Ru–CoFe 2 O 4 /RGO were used simultaneously to reduce Cr(VI) and anodic oxidation of phenol. • Ru–CoFe 2 O 4 /RGO photoelectrode has good recyclability and high stability. [ABSTRACT FROM AUTHOR]

Abstract: We fabricated efficient, white phosphorescent organic light-emitting diodes (WPhOLEDs) with all of blue, yellow, and deep-red iridium(III) complexes doped in 4,4′,4″-tris(cabazol-9-yl)triphenylamine [or 1,3-bis(carbazol-9-yl)benzene)]:poly(9-vinylcarbazole):1,3-bis[2-(4-tert-butylphenyl)-1,3,4,-oxadiazo-5-yl] mixed-host system and investigated their photophysical, electrochemical, and electroluminescent properties. An optimal combination of blue, yellow, and deep-red iridium(III) complexes improved the charge balance and triplet excitons confinement in the emitting layer. We fabricated the WPhOLEDs with a configuration of indium tin oxide/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (40 nm)/emitting layer (50–60 nm)/1,3,5-tri[(3-pyridyl)-phen-3-yl]benzene (20 nm)/lithium fluoride (1 nm)/aluminum (150 nm). In terms of performance, the WPhOLEDs exhibited a maximum luminance efficiency of 23.04 cd/A and external quantum efficiency of 11.45%. [Copyright &y& Elsevier]

The intensive research on the synthesis and characterization of gold (Au) nanostructures has been extensively documented over the last decades. These investigations allow the researchers to understand the relationships between the intrinsic properties of Au nanostructures such as particle size, shape, morphology, and composition to synthesize the Au nano/hybrid nanostructures with novel physicochemical properties. By tuning the properties above, these nanostructures are extensively employed to detect and remove trace amounts of toxic pollutants from the environment. This review attempts to document the achievements and current progress in Au-based nanostructures, general synthetic and fabrication strategies and their utilization in electrochemical sensing and environmental remediation applications. Additionally, the applications of Au nanostructures (e.g., as adsorbents, sensing platforms, catalysts, and electrodes) and advancements in the field of electrochemical sensing of different target analytes (e.g., proteins, nucleic acids, heavy metals, small molecules, and antigens) are summarized. The literature survey concludes the existing methods for the detection of toxic contaminants at various concentration levels. Finally, the existing challenges and future research directions on electrochemical sensing and degradation of toxic contaminants using Au nanostructures are defined. [Display omitted] • Au nanostructures in electrochemical detection and removal of toxic pollutants. • Fabrication strategies and synthesis methods have been elaborated. • Challenges for Au nanostructures in sensor and remediation fields are highlighted. • Influence of various parameters for electrochemical detection/removal is explored. • Effective electrochemical properties and future prospects are discussed. [ABSTRACT FROM AUTHOR]

Comparative experiments were conducted to determine the effects of various solvents (i.e., deionized water, methanol, ethanol, 1-propanol, butanol, ethylene glycol, hexane, and acetonitrile) on the final compositions, morphologies, and catalytic activities of copper-based nanoparticles (NPs). The NPs were effectively synthesized by pulsed laser ablation (PLA) using a copper plate as the target. The obtained copper NPs were characterized utilizing various analytical techniques. It was established that the developed methodology allows for the production of NPs with different morphologies and compositions in a safe and simple manner. When laser ablation of a solid copper plate was performed in acetonitrile, the formation of copper(I) cyanide cubes was observed. On the other hand, in deionized water and methanol, spherical and rod-like particles of copper(I) and copper(II) oxide were detected, respectively. The catalytic activity of the prepared copper NPs in the reduction of aromatic nitro compounds, such as 4-nitrophenol and nitrobenzene, was also evaluated. A high k value was determined for the reduction over the copper(II) oxide NPs produced in methanol. Moreover, particles with graphitic carbon (GC) layers exhibited superior catalytic performance in the reduction of a hydrophobic substance, i.e., nitrobenzene, over the reduction of 4-nitrophenol. The enhanced catalytic activity of this catalyst may be due its unique surface morphology and the synergistic effects between the copper nanostructure and the GC layer. Lastly, a detailed reduction pathway mechanism for the catalytic reduction of 4-nitrophenol and nitrobenzene has been proposed. ga1 • Copper nanoparticles were synthesized in various organic solvents using PLA method. • Solvent effect on composition and morphology of final nanomaterials was studied. • Formation of CuCN during PLA in acetonitrile was observed for the first time. • Growth mechanism of CuO rods in alcohols was supported by theoretical calculations. • Copper-based materials showed catalytic activity in removal of nitro compounds. [ABSTRACT FROM AUTHOR]