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Aquatic insects have developed versatile locomotion mechanisms that have served as a source of inspiration for decades in the development of small‐scale swimming robots. However, despite recent advances in the field, efficient, untethered, and integrated powering, actuation, and control of small‐scale robots remains a challenge due to the out‐of‐equilibrium and dissipative nature of the driving physical and chemical phenomena. Here, we have designed small‐scale, bioinspired aquatic locomotors with programmable deterministic trajectories that integrate self‐propelled chemical motors and photoresponsive shape‐morphing structures. A Marangoni motor system is developed integrating structural protein networks that self‐regulate the release of chemical fuel with photochemical liquid crystal network (LCN) actuators that change their shape and deform in and out of the surface of water. While the diffusion of fuel from the motor system regulates the propulsion, the dissipative photochemical deformation of LCNs provides locomotors with control over the directionality of motion at the air‐water interface. This approach gives access to five different but interchangeable modes of locomotion within a single swimming robot via morphing of the soft structure. The proposed design, which mimics the mechanisms of surface gliding and posture change of semiaquatic insects such as water treaders, offers solutions for autonomous swimming soft robots via untethered and orthogonal power and control. [ABSTRACT FROM AUTHOR]

The visible light‐induced decarboxylative cascade reaction of fluoroalkyl carboxylic acids has been achieved for the efficient synthesis of fluorinated compounds. However, most of the transformations rely on noble iridium metal complex. Herein, a visible light‐induced metal‐free decarboxylative cascade reaction of fluoroalkyl carboxylic acids has been realized. This protocol features simple operation, transition metal free, and good functional group tolerance. [ABSTRACT FROM AUTHOR]

In recent years, the functionalization of 1,3‐butadiene has become an attractive strategy for constructing allyl compounds with molecular and structural complexity, and the current research focuses on synthetic chemistry and organic synthesis. Compared with the traditional synthesis method, the synthesis methods promoted by photochemistry or electrochemistry represent an environmentally friendly and mild strategy. In this review, the functionalization reactions of 1,3‐butadiene under photochemical/electrochemical processes in recent years are reviewed according to the classification of functionalization systems, with particular emphasis on the corresponding reaction mechanism, which lays a foundation for further exploration of new catalytic methods. [ABSTRACT FROM AUTHOR]

The molecularly doped poly(3-hexylthiophene) (P3HT) was used for the first time as a photocathode for reducing oxygen to H2O2. For this purpose, a P3HT film was doped with hexaazatriphenylenehexacarbonitrile, which increased the oxygen reduction current at an applied negative potential in the dark. Visible light illumination of the doped P3HT film significantly facilitated the oxygen reduction with a high current density and shifted the onset potential beyond the reaction equilibrium potential. The oxygen reduction performance of the doped P3HT film is discussed in relation to the energy level diagram. [ABSTRACT FROM AUTHOR]

Herein we report a visible‐light‐induced trifluoromethylative difunctionalization of styrenes and phenylacetylenes using trifluoromethyl thianthrenium triflate (TT‐CF3+OTf−). The transformation was enabled by the discovery of a photoactive catalytic EDA complex formed between carbazolyl dithiocarbamate and TT‐CF3+OTf−. This three‐component reactivity platform establishes a new paradigm for TT‐CF3+OTf−, significantly expanding its repertoire of photochemically enabled trifluoromethylation reactions. [ABSTRACT FROM AUTHOR]

This manuscript describes the development of alkyne addition to the aziridine moiety of aziridinoquinoxalines using dual Ir(III)/Cu(I) catalytic system under green light‐emitting diode (LED) photolysis (λmax=525 nm). This mild method features high levels of chemo‐ and regioselectivity and was used to generate 30 highly functionalized substituted dihydroquinoxalines in 36–98 % yield. This transformation was also carried asymmetrically using phthalazinamine‐based chiral ligand to provide 9 chiral addition products in 96 : 4 to 86 : 14 e.r. The experimental and quantum chemical explorations of this reaction suggest a mechanism that involves Ir(III)‐catalyzed triplet energy transfer followed by a ring‐opening reaction ultimately leading to the formation of azomethine ylide intermediates. These azomethine intermediates undergo sequential protonation/copper(I) acetylide addition to provide the products. [ABSTRACT FROM AUTHOR]

Purpose: To report a case of a full-thickness macular hole after exposure to an extremely powerful handheld laser pointer. Methods: A 14-year-old boy with a laser-induced full-thickness macular hole was evaluated 1 month after a momentary exposure to a 5,000 mW blue laser pointer. Imaging modalities including fundus color, autofluorescence, and spectral-domain optical coherence tomography, acquired both at our clinic and by the referring physician soon after the injury, are used to describe the clinical evolution of the case. Results: Soon after the injury, an intensely white, circular opacification of the retina approximately 400 μm in diameter was seen in the fovea. Early spectral-domain optical coherence tomography images showed full-thickness hyperreflectivity, likely representing tissue necrosis. One month later, a full-thickness macular hole and eradication of the retinal pigment epithelium at its base were evident in the fundus color, autofluorescence, and spectral-domain optical coherence tomography images. Conclusion: High-power laser pointers have become easily available online. The presenting findings after exposure to such high-power devices are distinct from those reported after exposure to weaker laser pointers. Although long exposure to weaker lasers typically produces extensive, calligraphic figures and yellow placoid lesions involving only the outer retina, in our case, a very brief exposure led to focal full-thickness injury of the fovea. [ABSTRACT FROM AUTHOR]

Correlating damage outcomes to a retinal laser exposure is critical for diagnosis and choosing appropriate treatment modalities. Therefore, it is important to understand the causal relationships between laser parameters, such as wavelength, power density, and length of exposure, and any resulting injury. Differentiating photothermal from photochemical processes in an in vitro retinal model using cultured retinal pigment epithelial cells would be a first step in achieving this goal. The first-order rate constant of Arrhenius has been used for decades to approximate cellular thermal damage. A modification of this equation, called the damage integral (Ω), has been used extensively to predict the accumulation of laser damage from photothermal inactivation of critical cellular proteins. Damage from photochemical processes is less well studied and most models have not been verified because they require quantification of one or more uncharacterized chemical species. Additionally, few reports on photochemical damage report temperature history, measured or simulated. We used simulated threshold temperatures from a previous in vitro study to distinguish between photothermal and photochemical processes. Assuming purely photochemical processes also inactivate critical cellular proteins, we report the use of a photothermal Ω and a photochemical Ω that work in tandem to indicate overall damage accumulation. The combined damage integral (ΩCDI) applies a mathematical switch designed to describe photochemical damage relative to wavelength and rate of photon delivery. Although only tested in an in vitro model, this approach may transition to predict damage at the mammalian retina.

Several evolving therapies depend on the delivery of therapeutic cargo into the cytoplasm. Engineered magnetic nanoparticles (MNPs) have played a pivotal role in advancing and modernizing cancer theranostics, vaccination and gene therapies. The main advantages of MNP-based delivery approaches are due to their potential to decrease the side effects by targeting specific cell types, shielding delicate therapeutics from early degradation, increasing the solubility of hard-to-deliver drugs and long-sustained and precise release of these drugs. Like other nanoparticles (NPs), MNPs enter cells by endocytosis and are frequently stuck inside endocytic vesicles, which mature into early and late endosomes and accumulate in the lysosome. Endocytosed MNPs are ultimately degraded in lysosomes or recycled towards the cell membrane. Thereby, they must escape endocytic vesicles on a priority basis. Endosomal escape is highly important for the effectiveness of nanoparticle-based treatments. This review is concerned with the use of magnetic nanoparticles (MNPs) as functional nano-objects to enhance the therapeutic effects by disrupting or rupturing the endocytic vesicles in terms of endosomal escape. The current strategies and future challenges concerning an efficient endosomal escape of MNPs are discussed in this review.

Carbonate radical anion (CO3.− ${\mathrm{C}{\mathrm{O}}_{3}}^{.-}$) is generally overlooked in atmospheric chemistry. Our recent work emphasizes the important role of carbonate radicals produced on mineral dust surfaces in fast sulfate production under solar irradiation in the presence of CO2 at specifically low RH and light intensity. Yet so far how CO3.− ${\mathrm{C}{\mathrm{O}}_{3}}^{.-}$ involves and affects secondary sulfate production under diverse RH, light intensity, and complex constituent matrix remains unknown, which essentially limits our comprehensive knowledge of CO3.− ${\mathrm{C}{\mathrm{O}}_{3}}^{.-}$initiated SO2 oxidation scheme in the atmosphere. Herein, we explored the heterogeneous SO2 oxidation over both model and authentic dust and clays in the presence of CO2 at atmospheric relevant RHs and light intensities. Interestingly, we observe that CO2 promotes sulfate yield over authentic dust and clays at atmospheric‐relevant RH and light intensity. This observation relates to the favorable kinetic between SO2 oxidation and CO3.− ${\mathrm{C}{\mathrm{O}}_{3}}^{.-}$ while auto‐quenching of these radical ions is largely minimized due to the sufficient sites of crustal constituents. Furthermore, employing a suite of authentic dust and machine learning strategies, we evaluated the relative importance of each constituent within airborne minerals or clays as well as environmental conditions including relative humidity, light intensity, and CO2 concentration in affecting SO2 uptake capability. On this basis, sulfate formation mediated by dust‐driven pathway, accounting for nearly ∼20.9% of overall contribution by the end of this century during some pollution episodes, even higher than gas‐phase ·OH $\cdot \text{OH}$ (∼16.9%), will be increased by 163% if CO2‐initiated SO2 oxidation scheme is incorporated. Plain Language Summary: How carbonate radical ions involve and affect sulfate formation under different RHs, light intensities, and complex component matrices remains an open question. Secondary sulfate production is facilitated by CO3.− ${\mathrm{C}{\mathrm{O}}_{3}}^{.-}$ over authentic dust particles in atmospheric relevant RH and light intensity. More importantly, this research emphasizes that CO2 is not an inert greenhouse gas that rarely participates in atmospheric chemistry but a strong oxidant precursor that will produce CO3.− ${\mathrm{C}{\mathrm{O}}_{3}}^{.-}$ and subsequently trigger quick SO2 oxidation via chain reactions. This dust‐driven reaction channel mediated by CO3.− ${\mathrm{C}{\mathrm{O}}_{3}}^{.-}$ potentially contributes to nearly ∼1/5 of secondary sulfate production during some pollution hours if the growing intensive anthropogenic activities continue. Key Points: Carbonate radical‐initiated SO2 heterogeneous oxidation is sensitive to RH, CO2 concentration, light intensity, and dust constituentsCarbonate radicals promote atmospheric sulfate production on authentic dust and clay particles at haze‐relevant conditionsThis previously unrecognized scheme will account for ∼20.9% of overall atmospheric sulfate formation by the end of this century [ABSTRACT FROM AUTHOR]

The metal‐hydride hydrogen atom transfer (MHAT) method is widely recognized as a powerful technique for functionalizing alkenes. However, its application in the functionalization of industrial feedstock dienes and allenes is relatively rare due to challenges related to chemo‐selectivity. In recent studies, Co‐porphines have been identified as highly efficient catalysts under photoirradiation for MHAT, demonstrating an exceptional level of chemoselectivity for the functionalization of dienes and allenes, while disregarding other simple olefins present. This novel method enables the selective reductive coupling of pyridines with dienes and the allylation of aldehydes by the combination with Ti catalysis. Mechanistic studies and density functional theory (DFT) calculations support the idea that the non‐reversible transfer of hydrogen atoms from cobalt hydride to dienes and allenes, leading to the generation of allyl radicals, is the key step in the catalytic cycle. [ABSTRACT FROM AUTHOR]

This work reports the hydrogen production by homogeneous photoreforming assisted with ascorbic acid and ultrasound using a theraphthal, a water-soluble cobalt phthalocyanine salt. The homogeneous reactions were evaluated using mixtures of ethanol–water and isopropanol–water (50/50 v/v) under UV irradiation. A linear production of hydrogen through time was observed, showing higher generation using ethanol. The hydrogen amount keeps stable during three cycles of irradiation (~ 32 µmol). The H2 production is doubled with the combinative use of sonochemistry and UV irradiation, being related to the synergy effect between sonolytic and photolytic combined effects. Oxygen evolution in similar amounts was also observed. [ABSTRACT FROM AUTHOR]

Ni was successfully doped into WO3 lattice to enhance its photocatalytic activity. The Ni dopants acted as nuclei during crystallization leading to Ni-WO3 crystal size increase. However, the doped Ni substituted several W6+ of the WO3 leading to lattice distortion preventing agglomeration of these formed crystals resulting in Ni-WO3 particle size decrease. Therefore, Ni-WO3 crystals were larger than WO3 crystals while Ni-WO3 particles were much smaller than WO3 particles. Finally, Ni dopants created a transitional level between conduction and valence bands of the WO3 to narrow its band gap and to increase charge separation to improve photocatalytic Tetracycline degradation efficiency. [ABSTRACT FROM AUTHOR]

Photochemistry related studies have been driven by with the application of new types of photocatalysis. Lately boron-dipyrromethene (BODIPY) as distinguished chromophore with exceptional photophysical and chemical features has emerged as a viable photosensitizer. Within this context, three new NDI-BODIPY triads (8–10) were synthesized/ characterized and used to investigate the efficiencies of singlet oxygen generation and oxidation of 1,5-dihydroxynapthalene to juglone under visible light. Singlet oxygen generation was determined both via indirect method by using 1,3-diphenylisobenzofuran as trap molecule and from the characteristic 1O2 phosphorescence at 1270 nm. Also, NDI with BODIPY dyes bearing bromine and iodine atoms were shown to be highly active photocatalysts in which the activities are comparable or higher to the readily available commercial systems where 36% (9) and 66% (10) juglone production was achieved under 15 min. This work may emphasize good example of applying NDI-BODIPY based triads as photocatalysts for a series of important organic transformations. [ABSTRACT FROM AUTHOR]

Ionic liquids (ILs) are the class of materials which are purely ionic in nature and liquid at room temperature. Their remarkable properties like very low vapour pressure, non-inflammable and high heat resistance are responsible for their use as a very appealing solvent in a variety of industrial applications in place of regular organic solvents. Because ILs are water soluble to a certain extent, the industrial wastewater effluents are found to contaminate with their traces. The non-biodegradability of ILs attracts the attention of the researchers for their removal or degradation from wastewater. Numbers of methods are available for the treatment of wastewater. However, it is very crucial to use the most efficient method for the degradation of ILs. Advanced oxidation process (AOP) is one of the most important techniques for the treatment of ILs in wastewater which have been investigated during last decades. This review paper covers the cost-effective Fenton, photochemical and photocatalytic AOPs and their combination that could be applied for the degradation of ILs from the wastewater. Theoretical explanations of these AOPs along with experimental conditions and kinetics of degradation or removal of ILs from water and wastewater have been reported and compared. Finally, future perspectives of IL degradation are presented. [ABSTRACT FROM AUTHOR]

In this research, a novel method for manufacturing silicon (Si) nanoparticles (NPs) has been proposed. The process involves the use of ultraviolet (UV) irradiation and acrylic acid (AA) to induce Si NPs-AA polymerization. Si particles of varying sizes and an AA dispersion solution were subjected to UV radiation, leading to the formation of Si NPs coated with AA polymer, which separated to the top due to the volume increase. The Fourier-transform infrared (FT-IR) spectra confirmed the reaction between Si and AA by verifying the peak positions of the newly formed Si–C bond. The physical and chemical particle size measurements revealed that the Si NPs were surrounded by short-chain AA polymer clusters, accounting for approximately 15% of the cluster weight. Moreover, the Si particles' oxidation temperature in the Si NPs-AA cluster significantly decreased to about 450 °C. This technology holds promising potential for use in luminescent semiconductor materials, as it enables the selective separation of Si NPs. [ABSTRACT FROM AUTHOR]

This study presents the synthesis of some metal {M = Zn(II), Lu(III), Si(IV)} phthalocyanines bearing chlorine and 2-(4-methylthiazol-5-yl) ethoxy groups at peripheral or axial positions. The newly synthesized metal phthalocyanines were characterized by applying FT-IR, 1H NMR, mass, and UV-Vis spectroscopic approaches. Additionally, the surface of gold nanoparticles was modified with zinc(II) and silicon(IV) phthalocyanines. The resultant nanoconjugates were characterized using TEM images. Moreover, the effect of metal ions and position of substituent, and gold nanoparticles on the photochemical and sonophotochemical properties of the studied phthalocyanines was investigated. The highest singlet oxygen quantum yield was obtained for the lutetium phthalocyanine by applying photochemical and sonophotochemical methods. However, the linkage of the zinc(II) and silicon(IV) phthalocyanines to the surface of gold nanoparticles improved significantly their singlet oxygen generation capacities. [ABSTRACT FROM AUTHOR]

Polysubstituted furans are widespread structural motifs, extensively dispersed in natural products, in numerous bioactive compounds, pharmaceuticals, agrochemicals and organic functional materials. Hence, the development of rapid and competent methodologies for the synthesis of multisubstituted furans has drawn much attention over the years. This review summarizes the synthesis of polysubstituted furans using transition‐metal catalyzed, transition metal‐free, photochemical and electrochemical approaches with plausible mechanistic insights. In each reaction, the highest yields of di‐, tri‐ or tetrasubstituted furans are highlighted and some applications of the methodology towards the synthesis of natural products and biologically active compounds are mentioned. The present review highlights the recent progresses in the synthesis of polysubstituted furans reported from 2019 to 2023. [ABSTRACT FROM AUTHOR]

Characterization of grain nutritional and quality traits was done in a total of 192 exotic and indigenous rice genotypes were genetically characterized for 16 grain nutritional and quality traits. Substantial genetic variability was observed for all the traits. The coefficient of variation was maximum for flavonoid content (87.10%) and minimum for kernel breadth (11.90%). The estimated coefficient of skewness and kurtosis indicated the presence of genetic interaction among the traits. Based on grain shape 4, 37, 31, 65 and 55 rice genotypes were classified as short slender, short bold, medium slender, long slender and long bold respectively. Further, kernel length was negatively associated with zinc, iron, phenolics and flavonoid contents. Amylose content was positively associated with protein, phenolics and flavonoid contents suggesting that such relationship could serve as grain indices for indirect selection of genotypes. Four genotypes- Oryza officinalis, Oryza latifolia, IC435559 and IC135877 were identified as donors for zinc and iron contents. The genotypes- IC74637, IC301547, IC301589 and IC301625 were identified as potential donors for both phenolics and flavonoid. Five genotypes viz., IC379109, IC331668, Mancha (M:1028), Dubraj (D:1251) and Laxmibhog (L:708) were identified for grain yield, quality and nutritional traits. The identified donors will be useful to develop nutrient dense biofortified varieties.

Ascorbic acid (AA) is a highly sensitive nutrient, which degrades at high temperatures (>60 °C), in the presence of metal ions and oxygen. There is a dearth of studies on the effect of pasteurization on AA in juices. This review attempts to propose a mechanism for the degradation of AA during ultraviolet (UV) and pulsed light (PL) treatments. While photodegradation and aerobic degradation contribute to AA degradation during UV and PL treatments, the anaerobic degradation is the most significant mechanism post UV and PL treatments during storage. The photodegradation of AA results in the formation of ascorbyl radicals, which get converted to dehydroascorbic acid (DHAA). These radicals generated during the UV and PL treatment can induce a cascade of reactions, which can prolong the degradation of AA during storage. The factors influencing AA degradation during UV and PL treatment include extrinsic factors, which majorly include process variables such as fluence, voltage, and temperature of UV and PL processing. The intrinsic factors of the juice such as pH, dissolved oxygen, enzymes, peroxides, sugars, polyphenols, and metal ions significantly affect the AA content in juices. Since the major objective of UV and PL pasteurization is ensuring microbial safety and enzymatic stability, a careful optimization of the process conditions is necessary to achieve maximal retention of bioactives, such as AA. It can be concluded that photodegradation, aerobic oxidation and anaerobic degradation are the major mechanisms governing the degradation of AA in juices.

The twisted intramolecular charge transfer (TICT) and excited state intramolecular proton transfer of H2L has been explored based by density functional theory and time-dependent density functional theory methods. The results show that there are mainly two conformers of H2L-A and H2L-B. The presence of TICT state induced by photo-induced electron transfer process is related to fluorescence quenching behavior in the sensor. The sensor H2L detects and discriminates Al3+ and Zn2+ successfully by regulating solvents (from protic to aprotic) via a turn-on fluorescence signaling. The above conclusions were also verified by FMOs and electron spectra. [ABSTRACT FROM AUTHOR]

Dihydroquinolin-2(1H)-ones (DHQOs) represent a class of valuable bioactive compounds with six-membered nitrogen-containing heterocyclic structures. The development of simple, mild, and efficient synthetic methods has been widely considered by synthetic chemists. In this review, we have summarized a series of different synthetic strategies for the synthesis of DHQOs via the catalytic annulation of α,β-unsaturated N-arylamides in the past decade, including covering electrophilic cyclization, radical initiated cyclization, and photochemical cyclization reactions. Additionally, the substrate scope and mechanistic details are also discussed. This paper provides a useful reference for the development of diverse synthesis methodologies of DHQO. [ABSTRACT FROM AUTHOR]

Ultrafine Pt nanoparticles (Pt/SWCNTs) supported on single-walled carbon nanotubes (SWCNTs) were prepared by a photochemical method assisted by ethylene glycol (EG) as a reducing agent without the addition of stabilizing agents. the application in the reduction of 4-Nitrophenol (4-NP) was also explored. XRD diffraction patterns show that the content of Pt (111) crystal planes is higher, which is beneficial for improving the catalytic activity of platinum nanoparticles. TEM results showed that Pt/SWCNTs-E3 prepared under Ultra Violet (UV) light irradiation had a small-size particle with an average particle size of about 2.2 nm. XPS results showed that the prepared Pt nanoparticles mainly existed in the form of Pt0. The catalytic performance test results showed that the Pt/SWCNTs prepared under the UV condition of 395 nm had the highest activity for catalyzing the reduction of 4-NP, and the apparent rate constant was k = 0.34 min−1, indicating that it had good catalytic activity. After seven cycles, the conversion rate remains about 83%, which has good reusability and stability. The results show that the aggregation of Pt intermediates can be effectively controlled by photo-induced and strong metal − support interaction (SMSI) to obtain ultrafine nanoparticles dominated by Pt0. [ABSTRACT FROM AUTHOR]

Photopolymerizable resins are increasingly used to generate complex 3D printed parts through stereo lithography, digital light processing (DLP) and liquid crystal display (LCD) 3D printing. Many challenges relating to the resin chemistry and printing parameters still exist and must be addressed in order to entirely control the properties of parts after printing. This work reviews the current knowledge and describes the potential of DLP/LCD methods for printed acrylate resins, as well as the steps necessary to achieve a better control over the mechanical properties of printed materials. [ABSTRACT FROM AUTHOR]

Since WO3 is a relatively abundant metal oxide and features the ability to absorb in the visible spectrum, this non-toxic semiconductor is a promising photocatalyst among sustainable materials. These properties have delivered intriguing catalytic results in the conversion of methane to methanol; however, initial investigations indicate low photocatalytic efficiency resulting from fast recombination of photogenerated charges. To explore this aspect of inefficiency, five different morphologies of WO3 consisting of micron, nanopowder, rods, wires, and flowers were obtained and characterized. In addition, several electron capture agents/oxidizers were investigated as a means of improving the separation of photogenerated charges. The photocatalytic activity of different morphologies was assessed via CH3OH formation rates. Based on our results, WO3 flowers produced the highest methanol productivity (38.17 ± 3.24 µmol/g-h) when 2 mM H2O2 was present, which is approximately four times higher in the absence of H2O2. This higher methanol production has been attributed to the unique structure-related properties of the flower-like structure. Photoluminescence emission spectra and diffuse reflectance data reveal that flower structures are highly catalytic due to their reduced electron/hole recombination and multiple light reflections via petal-like hollow chambers.

Co-catalysts decorations provide unique opportunity in promoting the photocatalytic water splitting performance of graphite carbon nitride (g-C3N4) system, while mechanistic understanding of this complex catalytic network remains elusive. Here, taking the single-atom-based photocatalysts (M1-g-C3N4) as an unprecedented simplified model system, we theoretically tracked the photocatalytic kinetics for a comprehensive understanding of the photocatalytic process and afforded the descriptor αS1-T1/αT1-S0 (ratio of the extent of S1-T1 and T1-S0 state mixing) and ΔGH* (hydrogen adsorpti on free energy) for rational screening of photocatalysts. The targeted Fe1-g-C3N4 yields an excellent H2 evolution rate (ca. 3.2 ⋅mmol⋅gcat -1 ⋅h-1 under full arc), two order of magnitude improvement relative to pristine g-C3N4 counterpart and also outperforms other representative 3d-transition-metal-based photocatalysts. This work presents a comprehensive understanding of the essential role of isolated atomic sites in the photocatalytic course and sheds light on the design of photocatalysts from both photophysical and photochemical aspects. [ABSTRACT FROM AUTHOR]

The degradation of dyes is a difficult task due to their persistent and stable nature; therefore, developing materials with desirable properties to degrade dyes is an important area of research. In the present study, we propose a simple, one-pot mechanochemical approach to synthesize CuO nanoparticles (NPs) using the leaf extract of Seriphidium oliverianum, as a reducing and stabilizing agent. The CuO NPs were characterized via X-ray diffraction (XRD), scanning electron microscopy (SEM), photoluminescence (PL) and Fourier-transform infrared spectroscopy (FTIR). The photocatalytic activity of CuO NPs was monitored using ultraviolet-visible (UV-Vis) spectroscopy. The CuO NPs exhibited high potential for the degradation of water-soluble industrial dyes. The degradation rates for methyl green (MG) and methyl orange (MO) were 65.231% ± 0.242 and 65.078% ± 0.392, respectively. Bio-mechanochemically synthesized CuO NPs proved to be good candidates for efficiently removing dyes from water. [ABSTRACT FROM AUTHOR]

Since WO3 is a relatively abundant metal oxide and features the ability to absorb in the visible spectrum, this non-toxic semiconductor is a promising photocatalyst among sustainable materials. These properties have delivered intriguing catalytic results in the conversion of methane to methanol; however, initial investigations indicate low photocatalytic efficiency resulting from fast recombination of photogenerated charges. To explore this aspect of inefficiency, five different morphologies of WO3 consisting of micron, nanopowder, rods, wires, and flowers were obtained and characterized. In addition, several electron capture agents/oxidizers were investigated as a means of improving the separation of photogenerated charges. The photocatalytic activity of different morphologies was assessed via CH3OH formation rates. Based on our results, WO3 flowers produced the highest methanol productivity (38.17 ± 3.24 µmol/g-h) when 2 mM H2O2 was present, which is approximately four times higher in the absence of H2O2. This higher methanol production has been attributed to the unique structure-related properties of the flower-like structure. Photoluminescence emission spectra and diffuse reflectance data reveal that flower structures are highly catalytic due to their reduced electron/hole recombination and multiple light reflections via petal-like hollow chambers. [ABSTRACT FROM AUTHOR]

Inhaled glucocorticoids form the mainstay of asthma treatment because of their anti-inflammatory effects in the lung. Exposure to the air pollutant ozone (O3) exacerbates chronic airways disease. We and others showed that presence of the epithelial-derived surfactant protein-D (SP-D) is important in immunoprotection against inflammatory changes including those induced by O3 inhalation in the airways. SP-D synthesis requires glucocorticoids. We hypothesized here that O3 exposure impairs glucocorticoid responsiveness (including SP-D production) in allergic airway inflammation. The effects of O3 inhalation and glucocorticoid treatment were studied in a mouse model of allergic asthma induced by sensitization and challenge with Aspergillus fumigatus (Af) in vivo. The role of O3 and glucocorticoids in regulation of SP-D expression was investigated in A549 and primary human type II alveolar epithelial cells in vitro. Budesonide inhibited airway hyperreactivity, eosinophil counts in the lung and bronchoalveolar lavage (BAL) and CCL11, IL-13, and IL-23p19 release in the BAL of mice sensitized and challenged with Af (p < 0.05). The inhibitory effects of budesonide were attenuated on inflammatory changes and were completely abolished on airway hyperreactivity after O3 exposure of mice sensitized and challenged with Af. O3 stimulated release of pro-neutrophilic mediators including CCL20 and IL-6 into the airways and impaired the inhibitory effects of budesonide on CCL11, IL-13 and IL-23. O3 also prevented budesonide-induced release of the immunoprotective lung collectin SP-D into the airways of allergen-challenged mice. O3 had a bi-phasic direct effect with early (48 h) activation of SP-D mRNA (sftpd) in vitro. Dexamethasone and budesonide induced sftpd transcription and translation in human type II alveolar epithelial cells in a glucocorticoid receptor and STAT3 (an IL-6 responsive transcription factor) dependent manner. Our study indicates that O3 exposure counteracts the effects of budesonide on airway inflammation, airway hyperreactivity, and SP-D production. We speculate that impairment of SP-D expression may contribute to the acute O3-induced airway inflammation. Asthmatics exposed to high ambient O3 levels may become less responsive to glucocorticoid treatment during acute exacerbations.

Monolayer transition metal dichalcogenide (TMDs) are promising candidates for two-dimensional (2D) ultrathin, flexible, low-power, and transparent electronics and optoelectronics. However, the performance of TMD-based devices is still limited by the relatively low carrier mobility and the large contact resistance between the semiconducting 2D channel material and the contact metal electrodes. Phase-engineering in monolayer TMDs showed great promise in enabling the fabrication of high-quality hetero-phase structures with controlled carrier mobilities and heterojunction materials with reduced contact resistance. However, to date, general methods to induce phase-change in monolayer TMDs either employ highly-hostile organometallic compounds, or have limited compatibility with large-scale, cost-effective device fabrication. In this paper, we report a new photochemical method to induce semiconductor to metallic phase transition in monolayer MoS2 in a benign chemical environment, through a bench-top, cost-effective solution phase process that is compatible with large-scale device fabrication. It was demonstrated that photoelectrons produced by the band-gap absorption of monolayer MoS2 have enough chemical potential to activate the phase transition in the presence of an electron-donating solvent. This novel photochemical phase-transition mechanism advances our fundamental understanding of the phase transformation in 2D transition metal dichalcogenides (TMDs), and will open new revenues in the fabrication of atomically-thick metal-semiconductor heterostructures for improved carrier mobility and reduced contact resistance in TMD-based electronic and optoelectronic devices.

Porphyrins have multiple roles in living and nonliving systems because of their exceptional tunable chemical and physical properties. They are interesting macrocyclic compounds that could be modified in a number of ways. The structural diversity of porphyrinoids make them a unique choice for functional devices exhibiting photo‐ and electrochemical properties. Their properties can be modified or altered by either protonating the nitrogen atoms or by inducing charge transfer to the metal center. Structural changes induced by flattening and planar distortions, redox reactions, solvents, and porphyrin aggregations also influence the photo‐ and electro‐chemical properties of porphyrinoids. This review gives a brief explanation on the effects of structural orientation, molecular structure, and charge on the properties of porphyrinoids. The review also illustrates the correlation between the geometrical features and the photo‐ and electrochemical behavior of porphyrinoids. [ABSTRACT FROM AUTHOR]

Two new BODIPY-fluorene-fullerene (3) and BODIPY-fluorene-BODIPY (4) conjugates were designed, synthesized, and characterized for the first time. The structural properties of compounds were investigated with elemental analysis, mass, 1H, and 13C NMR techniques. Absorption and fluorescence spectroscopy were used to examine the photophysical (absorption and emission profiles, fluorescence quantum yields, and lifetimes) and photochemical (formation of singlet oxygen (1O2)) properties. It was observed that the novel compounds (3) and (4) showed high molar extinction coefficients and good 1O2 quantum yields. 1O2 formation ability of the BODIPY-fluorene-fullerene conjugate (3) was more efficient than that of the BODIPY-fluorene-BODIPY conjugate (4). Furthermore, photosensitization ability of both conjugate systems was more remarkable than some commonly used BODIPY based photosensitizers. The data presented in this work indicate that these two novel systems are effective 1O2 photosensitizers that might be used for various areas of applications such as photodynamic therapy and photocatalysis. [ABSTRACT FROM AUTHOR]

Despite the landmark of green revolution, our nation’s intensive chemical farming has severely polluted land, food, potable water, and air. When you eat food that was produced in these circumstances, the contaminants are taken into your body. Sustainable agriculture practiced by Agnihotra is the solution to our issues. Agni means ‘fire’. According to the Vedas, ‘HEAL THE ATMOSPHERE AND IT WILL HEAL YOU’, hotra signifies ‘going to heal’. The far more important feature of Agnihotra is that it unites the forces of the five variables of earth, air, water, sun and space to bring about tiny differences in biota. It is the vital spark in Homa farming. It is used when all hope is lost and has proven to be useful in raising crop output and minimizing microbial contamination pathogenicity, soil and water decontamination, pest and disease infestation. Regularly incorporating agnihotra will enhance the impact of that activity on the farm. [ABSTRACT FROM AUTHOR]

The synergetic effects of nickel (Ni) and graphene (G) as promotors for TiO2 on photocatalytic hydrogen production have been observed. Ni/TiO2, G/TiO2, and Ni-G/TiO2 were synthesized via a wet impregnation method. While G-TiO2 gave a similar H2 yield to that of the unmodified TiO2, Ni/TiO2 tripled it for the same reaction time. Surprisingly, Ni-G/TiO2 exhibits a 10-fold H2 production as compared to the unmodified case. A mechanism is proposed in which Ni and graphene cooperate for the betterment of photocatalytic hydrogen production by facilitating concerted trapping and relay of electrons, thereby realizing effective charge-carrier separation and conduction. [ABSTRACT FROM AUTHOR]

2,4,6-Triarylpyridines (TAPs) represent a versatile class of N -heterocycles with broad applications in many fields. This study presents an investigation on photochemical properties and acidochromism behavior of novel 2,6-bis(4-(dodecyloxy)phenyl)-4-(4-substituted-phenyl)pyridine-based derivatives (1a - 1g). Photochemical study in dichloromethane (DCM) and acetone (ACT) solutions showed a small solvent effect for the TAP derivatives, except for the carbazole derivative 1a , which was characterized as the most emissive material in all conditions, but especially in DCM solution for blue emission (λ EM = 406 nm, ϕ f = 0.36). The presence of electron-donating groups at the 4-phenyl moiety contributes to more intense and redshifted emissions in both DCM and ACT solutions, as well as in the solid state. In aqueous ACT, while TAPs bearing EDGs such as 1a presented more intense emissions depending on the water fraction, an opposite effect was verified for fluorinated derivative 1f. The acidochromism of selected TAPs 1a and 1f (fluorinated derivative) in aqueous acetone was characterized by the decreasing of the emission intensity at 436 nm and 388 nm, respectively, in the presence of aqueous HCl for both TAPs, however, the protonated 1f showed strong emission in higher wavelength (λ EM = 476 nm) in acidic medium. A 1H NMR study allowed a better understanding of the structural features associated to the acidochromism. The photochemical and acidochromism results obtained for the TAP derivatives are strongly supported by computational results, and particularly noteworthy is the favoring of the resonance effect as consequence of the decreasing in the torsion angle between the 4-alkoxyaryl substituents and the pyridine core after protonation of 1f. The emissive properties and acidochromism capacity of 1a and 1f allowed the potential application of TAP-adsorbed paper strips as disposable sensors for qualitative detection of gaseous HCl. [Display omitted] • Nonconventional TAPs were synthesized in moderate yields. • Photochemical results showed emission up to 0.36 in DCM solution for compound 1a. • AIEE was observed for TAP with EDG, notably N -carbazole derivative 1a. • Selected compound 1f showed interesting acidchromism. • Computational results support the experimental data. [ABSTRACT FROM AUTHOR]

Abstract Porphyrins have multiple roles in living and nonliving systems because of their exceptional tunable chemical and physical properties. They are interesting macrocyclic compounds that could be modified in a number of ways. The structural diversity of porphyrinoids make them a unique choice for functional devices exhibiting photo‐ and electrochemical properties. Their properties can be modified or altered by either protonating the nitrogen atoms or by inducing charge transfer to the metal center. Structural changes induced by flattening and planar distortions, redox reactions, solvents, and porphyrin aggregations also influence the photo‐ and electro‐chemical properties of porphyrinoids. This review gives a brief explanation on the effects of structural orientation, molecular structure, and charge on the properties of porphyrinoids. The review also illustrates the correlation between the geometrical features and the photo‐ and electrochemical behavior of porphyrinoids.

The asthmatic airways are highly susceptible to inflammatory injury by air pollutants such as ozone (O3 ), characterized by enhanced activation of eosinophilic granulocytes and a failure of immune protective mechanisms. Eosinophil activation during asthma exacerbation contributes to the proinflammatory oxidative stress by high levels of nitric oxide (NO) production and extracellular DNA release. Surfactant protein-D (SP-D), an epithelial cell product of the airways, is a critical immune regulatory molecule with a multimeric structure susceptible to oxidative modifications. Using recombinant proteins and confocal imaging, we demonstrate here that SP-D directly bound to the membrane and inhibited extracellular DNA trap formation by human and murine eosinophils in a concentration and carbohydrate-dependent manner. Combined allergic airway sensitization and O3 exposure heightened eosinophilia and nos2 mRNA (iNOS) activation in the lung tissue and S-nitrosylation related de-oligomerisation of SP-D in the airways. In vitro reproduction of the iNOS action led to similar effects on SP-D. Importantly, S-nitrosylation abolished the ability of SP-D to block extracellular DNA trap formation. Thus, the homeostatic negative regulatory feedback between SP-D and eosinophils is destroyed by the NO-rich oxidative lung tissue environment in asthma exacerbations.

UV irradiation of solutions of a guanidinate coordinated dimagnesium(I) compound, [{(Priso)Mg}2] 3 (Priso=[(DipN)2CNPri2]−, Dip=2,6‐diisopropylphenyl), in either benzene, toluene, the three isomers of xylene, or mesitylene, leads to facile activation of an aromatic C−H bond of the solvent in all cases, and formation of aryl/hydride bridged magnesium(II) products, [{(Priso)Mg}2(μ‐H)(μ‐Ar)] 4–9. In contrast to similar reactions reported for β‐diketiminate coordinated counterparts of 3, these C−H activations proceed with little regioselectivity, though they are considerably faster. Reaction of 3 with an excess of the pyridine, p‐NC5H4But (pyBut), gave [(Priso)Mg(pyButH)(pyBut)2] 10, presumably via reduction of the pyridine to yield a radical intermediate, [(Priso)Mg(pyBut⋅)(pyBut)2] 11, which then abstracts a proton from the reaction solvent or a reactant. DFT calculations suggest two possible pathways to the observed arene C−H activations. One of these involves photochemical cleavage of the Mg−Mg bond of 3, generating magnesium(I) doublet radicals, (Priso)Mg⋅. These then doubly reduce the arene substrate to give "Birch‐like" products, which subsequently rearrange via C−H activation of the arene. Circumstantial evidence for the photochemical generation of transient magnesium radical species includes the fact that irradiation of a cyclohexane solution of 3 leads to an intramolecular aliphatic C−H activation process and formation of an alkyl‐bridged magnesium(II) species, [{Mg(μ‐Priso−H)}2] 12. Furthermore, irradiation of a 1 : 1 mixture of 3 and the β‐diketiminato dimagnesium(I) compound, [{(DipNacnac)Mg}2] (DipNacnac=[HC(MeCNDip)2]−), effects a "scrambling" reaction, and the near quantitative formation of an unsymmetrical dimagnesium(I) compound, [(Priso)Mg−Mg(DipNacnac)] 13. Finally, the EPR spectrum (77 K) of a glassed solution of UV irradiated 3 is dominated by a broad featureless signal, indicating the presence of a doublet radical species. [ABSTRACT FROM AUTHOR]

Rapid population growth and ever-increasing energy consumption have resulted in increased environmental pollution and energy demands in recent years. Accordingly, studies and research on innovative and efficient ways of wastewater clean-up and exploiting eco-friendly and renewable energy sources such as sunlight have become a necessity. This review focuses on recent progress with photocatalysis for water splitting capabilities. It introduces photocatalysis and hydrogen as a fuel source, before moving on to explain water splitting. Then, the criteria for ideal photocatalytic materials are discussed along with current material systems and their limitations. Finally, it concludes on the TiO2 systems and their potential in future photocatalysis research. [ABSTRACT FROM AUTHOR]

Advanced oxidative processes (AOPs) are procedures used for the treatment of wastewater based on the generation of free radicals, such as hydroxyl (•OH) and carbonate anion (CO3•−) radicals. However, although contaminants are degraded in these processes, the by-products generated in this transformation can be a greater source of toxicity than the original compound, making ecotoxicological tests essential for monitoring the efficacy of these treatment processes. In this study, we examined the ecotoxicity of AOP by-products generated using peracetic acid (PAA) and sodium carbonate, with and without solar radiation, for the degradation of methylene blue dye, using the planarian Girardia tigrina as a test organism. Ecotoxicological tests evaluated the acute toxicity of the generated by-product in terms of lethal concentrations (LC50). Although in both assays the degradation of the dye was greater than 99%, higher toxicity was observed in the assay using PAA and carbonate in the absence of radiation. From the results obtained, we conclude that the by-product generated from the degradation of methylene blue dye by peracetic acid and sodium carbonate, with and without solar radiation, can pose risks to aquatic ecosystems if released directly into water bodies. [ABSTRACT FROM AUTHOR]

The nitrogen oxides (NOx) formed by photochemical reaction of surface nitrates raise significant concerns. However, little is known about the effect of visible light (>380 nm) on nitrate decomposition and the reaction mechanism. Herein, the decomposition of surface nitrates is investigated under visible light. The results indicate that visible light photocatalysis contributes significantly to nitrate decomposition. Monodentate nitrate (m‐NO3−) can be decomposed into NOx by photogenerated electrons starting from the weakly coordinated N−O bond. Water vapor promotes NOx generation because more stable bidentate nitrate (b‐NO3−) will be converted into m‐NO3− by surface hydroxyl groups through hydrogen bonding interactions. Alternatively, b‐NO3− can be directly decomposed to NO2− by NO attack, but this process is subject to photocatalytic oxidation. This work brings a new focus on the atmospheric NOx sources and provides a more nuanced understanding of nitrates decomposition processes. [ABSTRACT FROM AUTHOR]