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Alcohol Use Disorder (AUD) is a significant public health issue in the United States. It affects millions of individuals and their families and contributes to substantial societal and economic burdens. Despite the availability of some pharmacological treatments, there is still a pressing need to develop more effective therapeutic strategies to address the diverse range of symptoms and challenges associated with AUD. Catechol-O-methyltransferase (COMT) inhibition recently emerged as a promising new approach to treating AUD due to its potential to improve cognitive effects commonly associated with AUD. Tolcapone, an FDA-approved COMT inhibitor, has shown some promise for treating AUD; however, its ability to decrease drinking in ethanol-dependent rats has not been well-established. In this study, we evaluated the effects of tolcapone on operant, oral ethanol self-administration in non-dependent and dependent rats, and in rats that self-administered oral saccharin. To induce dependence, rats underwent the chronic intermittent exposure to vapor model, and their drinking levels were assessed during acute withdrawal from ethanol. Our results demonstrated that tolcapone attenuated responding for ethanol in dependent rats only, without affecting self-administration in non-dependent rats or rats self-administering saccharin. Moreover, we found that tolcapone was differentially effective in different estrous phases in female rats. These findings suggest that COMT inhibition, specifically using tolcapone, may be a valuable pharmacotherapy for treating AUD, particularly in individuals who are physically dependent on alcohol. Further research is needed to elucidate the precise mechanisms underlying the observed effects and to assess the potential of COMT inhibitors in a broader population of individuals with AUD.

Objective: Since the victory compass of the humanity-pathogen war is oriented in many ways toward the latter, it is necessary to develop new potent and biosafe antipathogenic agents. Methods: The research was designed to transform poisonous dinitro-ortho-cresol (DNOC) into powerful, wide-ranging, and biocompatible antimicrobial candidates. This transformation was achieved by using this poison to create a coumarin precursor labeled P-DNOC, from which ten coumarins were synthesized and coded DNOCU1–DNOCU10. Two kinds of investigations were carried out on the synthesized items: microbiological and biosafety. In the first one, four aerobic bacteriomers, four anaerobic bacteriomers, and two fungiomers of infection-causing types were included. On the other hand, two non-infectious bacteriomers, three healthy cellular species, and human blood were used in the second investigation. Results and discussion: The results indicated that the synthesized items demonstrated potent, broadspectrum, and biosafe antimicrobial activity against the test microbes. Also, the research revealed for the first time that coumarins with anti-anaerobic bacterial activity were better than metronidazole. Moreover, the antimicrobial activity and biosafety were found to be correlated with the presence and number of chloride functionalities in the off-side area. Conclusions: From the gathered results, it is concluded that the bad health outputs of DNOC can be modulated by transforming it into coumarins. These have high levels of biosafety and wide-spectrum antimicrobial potency, with supercity attributed to DNOCU9. In addition, this work provided the opportunity to convert the health-harming properties of nitrophenols into health-promoting candidates. This can be achieved by using coumarin-4-acetic acid and DNOCU9 as synthetic root and scaffold, respectively. [ABSTRACT FROM AUTHOR]

Nitrophenols present on the surface of particulates are ubiquitous in the atmosphere. However, its atmospheric photochemical transformation pathway remains unknown, for which the crucial effect of visible light is largely overlooked, resulting in an incomplete understanding of the effects of nitrophenols in the atmospheric environment. This study delves into the photolysis mechanism of 4-nitrophenol (4NP), one of the most abundant atmospheric nitrophenol compounds, on the surface of photoactive particulates under visible light irradiation. Unexpectedly, the nonradical species (singlet oxygen, ¹O2) was identified as a dominant factor in driving the visible photolysis of 4NP. The pathways of HONO and p-benzoquinone (C6H4O2) generation were clarified by acquiring direct evidence of C-N and O-H bond breakage in the nitro (-NO2) and hydroxyl (-OH) groups of 4NP. The further decomposition of HONO results in the generation of NO and hydroxyl radicals, which could directly contribute to atmospheric oxidizing capacity and complicate the PM2.5 composition. Significantly, the behavior of ¹O2-induced visible photolysis of 4NP was universal on the surface of common particulates in the atmosphere, such as Al dust and Fe2O3. This work advances the understanding of the pho-tochemical transformation mechanism of particulate-phase atmospheric nitrophenols, which is indispensable in elucidating the role of nitrophenols in atmospheric chemistry. [ABSTRACT FROM AUTHOR]

In this study, simultaneous quantification of 2-nitrophenol and 4-nitrophenol in their binary mixtures was investigated spectrophotometrically. Since the signals of analytes were highly overlapped, a multivariate partial least squares (PLS) technique was proposed to analyze the data. The PLS method makes the analysis possible without the need for the separation of analytes by tedious separation procedures or using expensive instrumentation techniques such as chromatographic methods. Both 2-nitrophenol and 4-nitrophenol possess acid-base properties and it was required to investigate the effect of pH on the FOM of the calibration. Therefore, at three pH conditions, the calibration processes were evaluated and the results showed the best FOM and the least root mean squares error of prediction (RMSEP) for both analytes were achieved for the augmented data at 3.45 and 8.95 of pHs where only neutral or anionic forms of analytes were present in the solution. The analytical sensitivity, limit of detection, R², and RMSEP were 108.3 ppm-1, 0.08ppm, 1.00, 0.04 ppm and; 163.2 ppm-1, 0.06 ppm, 0.9999, 0.04 ppm for 2-nitrophenol and 4-nitrophenol, respectively. [ABSTRACT FROM AUTHOR]

In this work, we developed cellulose acetate-stabilized zero-valent Cu nanoparticles by reducing metal cations using NaBH4 in a straightforward chemical process. Energy Dispersive X-ray Spectroscopy (EDS) was used for elemental analysis, Fourier-Transform Infrared Spectroscopy (FTIR) was used to identify the functional groups responsible for nanoparticle stabilization, and Field-Emission Scanning Electron Microscopy (FESEM) was used to characterize the morphology of the synthesized nanoparticles. Using para nitrophenol as a model pollutant, the effectiveness of the synthesized catalyst was evaluated. By introducing 15 mg of the catalyst, 2.5 mL of 0.1 mM PNP was completely reduced in 15 min, while NaBH4 served as a reducing agent, resulting in 94% reduction efficiency. To clarify the reduction mechanism, several kinetics models were used. The greatest R2 value (0.8099) was found in both the first and pseudo-first-order kinetics, with a rate constant of 0.1947. The second-order reaction had the highest rate constant (0.7407) and the lowest R2 value (0.6201), showing that the first-order kinetics model provided the best fit. Regression and analysis of variance (ANOVA) tests were also carried out to validate the reaction procedure. Moreover, the recyclability of the synthesized catalyst has been also checked showing that it is very reliable. The results of this investigation indicate that the synthesized CA@Cu can be used to effectively reduce and convert PNP to amino phenol. [ABSTRACT FROM AUTHOR]

Herein, a novel, green, and sustainable MoO3/ZIF-67/AmGO composite has been fabricated for the removal of notorious o-nitrophenols (o-NPs) from wastewater. Atriplex halimus L. (saltbush) served a dual function where the plant extract was used for the synthesis of molybdenum trioxide (MoO3) NPs, while the spent biomass-derived biochar was utilized as feedstock to produce green graphene oxide (GO). Ultimately, the MoO3/ZIF-67/AmGO composite was in situ fabricated by mixing MoO3 and AmGO with ZIF-67 during its preparation by the self-templating approach. Remarkably, the adsorption of o-NP onto MoO3/ZIF-67/AmGO attained equilibrium in just less than 10 min. The kinetics and isotherms analyses verified that the o-NP adsorption onto MoO3/ZIF-67/AmGO adhered to the Pseudo-2nd-order and Freundlich models, with a consistent qmax value of 500 mg/g. A conceivable adsorption mechanism was investigated in detail. Moreover, the ionic strength test implied the impact of the salting-out phenomenon in boosting o-NP adsorption. The eco-friendly MoO3/ZIF-67/AmGO proves to be a sustainable adsorbent, displaying excellent recyclability in consistently removing o-NP across multiple cycles. [ABSTRACT FROM AUTHOR]

The NO release following 266 nm photolysis of ortho and meta isomers of nitrophenol and nitroaniline shows a bimodal translational energy distribution, wherein the slow and fast components originate from dynamics in the S0 and T1 states, respectively. The translational energy distribution profiles for any NO product state show a higher slow-to-fast (s/f) branching ratio for the ortho isomer in comparison with the meta isomer. The observed variation in the s/f branching ratio vis-à-vis the ortho and meta isomers is attributed to the presence of intramolecular hydrogen bonding between the ortho substituent and NO2 moiety, which favours the roaming mechanism. [ABSTRACT FROM AUTHOR]

Bimetallic nanoparticles with synergistic effects revealed much higher catalytic activity than respective monometallic materials. This review describes bimetallic nanoparticles, especially silver nanoparticles, combined with the other transition elements, such as Ag−Fe, Ag−Co, Ag−Ni, and Ag−Cu, as an enhanced catalytically active material. The coverage is given to the various methods of preparation, in which factors responsible for different structures of bimetallic nanoparticles are thoroughly discussed. Lastly, we explore the use of bimetallic nanoparticles as a catalyst for the degradation of numerous organic pollutants that contribute to water pollution. [ABSTRACT FROM AUTHOR]

This work presents a comprehensive analysis of the adsorption of selected aromatic organic compounds on activated carbons. Both the equilibrium and kinetics of adsorption were studied using UV–Vis spectrophotometry. The influence of a number of factors: pH, contact time, presence of an accompanying substance, adsorbate concentration, as well as the mass and size of adsorbent grains, on the adsorption process from aqueous solutions was investigated. Phenol, 2-nitrophenol, 3-nitrophenol, 4-nitrophenol and methylene blue (as an accompanying substance) were selected as adsorbates. GAC 1240W and RIAA activated carbons were used as adsorbents. The equilibrium data were analyzed using the generalized Langmuir isotherm equation (R2 = 0.912–0.996). Adsorption rate data were fitted using a multi-exponential kinetic equation (1 − R2 = (1.0 × 10−6)–(8.2 × 10−4)). As an additional parameter, the half-time was also used to present the influence of selected factors on the adsorption kinetics. An increase in the amount of adsorption was demonstrated with increasing contact time as well as with decreasing solution pH and adsorbent grain size. For selected systems, an increase in the adsorption rate was observed with increasing adsorbate concentration, adsorbent mass and at lower pH values. In some cases, the presence of an accompanying substance also resulted in an increase in adsorption kinetics. In the tested experimental systems, optimal conditions for adsorption were established (T = 298 K, pH = 2, contact time: 7 days, grain diameter: >0.5 mm and the ratio of the mass of the adsorbent to the volume of the adsorbate solution: 1 g/L). Additionally, the acid–base properties (potentiometric titration), morphology (SEM) and structure (TEM) of the used adsorbents were also examined. [ABSTRACT FROM AUTHOR]

Nitrophenols are environmental pollutants and xenobiotics, the main sources of which are diesel exhaust fumes and pesticides. The biotransformation processes that take place in the liver are defence mechanisms against xenobiotics, such as nitrophenols. Our previous study showed that the chicken ovary is an additional xenobiotic detoxification place and that nitrophenols disrupt steroidogenesis in chicken ovarian follicles. Therefore, the present study aimed to determine the in vivo and in vitro effects of 4‐nitrophenol (PNP) and 3‐methyl‐4‐nitrophenol (PNMC) on the expression and activity of phase I (CYP3A) and phase II (COMT) biotransformation enzymes in chicken ovary. In an in vivo study, hens were treated with a vehicle or 10 mg PNP or PNMC/kg b.wt. per day for 6 days. In an in vitro study, prehierarchical white and yellowish follicles, as well as the granulosa and theca layers of the three largest preovulatory follicles (F3, F2 and F1), were isolated and then incubated in a control medium or medium supplemented with PNP (10−6 M) or PNMC (10−6 M) for 24 or 48 h. Both in vivo and in vitro studies showed that nitrophenols exert tissue‐ and compound‐dependent (PNP or PNMC) effects on CYP3A and COMT gene (real‐time PCR) protein (Western blot) expression and their activity (colorimetric methods). The inhibitory effect of nitrophenols in vivo on the activity of biotransformation enzymes suggest that the ovary has the capacity to metabolise PNP and PNMC. This study aimed to determine the in vivo and in vitro effects of 4‐nitrophenol (PNP) and 3‐methyl‐4‐nitrophenol (PNMC) on the expression and activity of phase I (CYP3A) and phase II (COMT) biotransformation enzymes in chicken ovary. The results revealed that nitrophenols have a tissue‐ and compound‐dependent (PNP or PNMC) effect on CYP3A and COMT expression and activity, indicating that they can disrupt endogenous compounds and xenobiotic metabolism. Additionally, nitrophenols may lead to ovarian cancer by COMT inhibition. [ABSTRACT FROM AUTHOR]

This study focuses on synthesizing ultrafine platinum nanoparticles (Pt/C60-E) by irradiating a mixture of C60 and K2[PtCl4] with ethylene glycol (EG) as the reducing agent. The process utilizes near-ultraviolet (UV) light at a wavelength of 395 nm, along with visible light at 450 and 650 nm. The composition and morphology of the Pt/C60 catalyst were investigated using characterization techniques including X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), and high-resolution transmission electron microscopy (HR-TEM). The results revealed a well-dispersed distribution of Pt nanoparticles on the C60 surface, with an average particle size of about 2.6 nm. In the catalytic reduction experiments of p-NP, the Pt/C60-E3 catalyst, prepared under near-ultraviolet irradiation (395 nm), exhibited superior catalytic activity, with a rate constant (k) of 0.12 min-1. Furthermore, in the catalyst cycling experiments, the catalysts remained highly active even after multiple cycles, demonstrating the effectiveness of the photochemical method in synthesizing precursor Pt catalysts. [ABSTRACT FROM AUTHOR]

Two newly designed ligands, [4-chloro-2-((((2-pyridyl)ethyl)imino)methyl)phenol] (HL1) and [4-bromo-2-((((2-pyridyl)ethyl)imino)methyl)phenol] (HL2), have been chosen to synthesize two Cu(II) dimeric Schiff base complexes, [CuL1Cl]2 (1) and [CuL2Cl]2 (2), with the aim of studying their catalytic activity towards oxidation of alcohols by using H2O2 as a terminal oxidant and reduction of nitroarenes by using NaBH4 as a reducing agent. The complexes have been characterized using physicochemical techniques and single crystal X-ray diffraction. DFT calculations of both the complexes have also been performed. Complex [CuL1Cl]2 (1) exhibited a higher catalytic efficiency in each reaction and therefore it was selected for building a magnetically separable catalyst by attaching it to surface modified magnetic nanoparticles. Then, our goal was to modify further complex 1 with iron oxide and isonicotinic acid (ISNA), for easy magnetic separation. The new Fe3O4@ISNA@CuL1 catalyst underwent comprehensive characterization, including FT-IR, SEM, TEM, and PXRD analyses, confirming successful copper complex immobilization on the magnetic nanoparticles. These catalysts maintained stability in aqueous and organic media, enabling alcohol oxidation with H2O2 in acetonitrile and nitroarene reduction with sodium borohydride in an aqueous environment. The surface modification with magnetic nanoparticles facilitated easy separation using an external magnet. The novelty of this work lies in its straightforward preparation, minimal time consumption, reduced use of hazardous chemicals, and cost-effectiveness. The catalysts showed recyclability up to five times without significant loss of activity. Furthermore, our synthesized catalysts demonstrated non-toxicity and environmental friendliness. [ABSTRACT FROM AUTHOR]

The magnitude of environmental problems caused by industrial progress is significant and cannot be ignored. Nanotechnology has made significant strides toward improving environmental protection. It is crucial to have reliable and eco-friendly approaches to creating nanoparticles in order to make progress in the field of nanotechnology. Our study successfully demonstrated a practical and environmentally friendly method for producing cobalt oxide nanoparticles using Morus alba leaves extract (MACo NPs). MACo NPs were produced by the reaction of 0.4 molar cobalt chloride with 40ml of extract (Morus alba leaves extract) solution at 60 °C for four hours. Different types of techniques, such as FTIR, XRD, SEM, and EDX, were used to examine the produced NPs. The effect of temperature, plant extract ratio, reaction duration, and salt ratio on the production of nanoparticles was monitored using UV–visible absorption spectrometry. The synthesized particles were around 24 nm in size and had a poly-shaped morphology. The Co NPs were thoroughly investigated and tested for antibacterial activity and catalytic degradation applications. The NPs exhibited excellent catalytic, antioxidant and antibacterial properties. Finally, MACo NPs' ability to degrade nitrophenols and disinfect pathogens provides a cost-effective and environmentally benign strategy for countering new and emerging pollutants. [ABSTRACT FROM AUTHOR]

Three triphenylamine‐ and s‐triazine‐based conjugated microporous polymers (TTPA, TTDATA, and TTMDATA) were prepared via the Friedel−Crafts arylation reactions under the catalytic action of CH3SO3H. In virtue of containing rich nitrogen atoms in their porous frameworks, the obtained TTPA, TTDATA, and TTMDATA possess good fluorescence sensing property for o‐nitrophenol (o‐NP) with high quenching coefficients of 1.54 × 104, 1.32 × 104, 1.33 × 103 L mol−1 and low limits of detection (LODs) of 2.44 × 10−9, 1.14 × 10−11, and 1.35 × 10−8 mol L−1, respectively. The fluorescent quenching mechanism of TTPA for selective sensing o‐NP is the photo‐induced charge‐transfer mechanism. However, the fluorescent quenching mechanisms of TTDATA and TTMDATA for selective sensing o‐NP have both the photo‐induced charge‐transfer mechanism and the resonant energy transfer mechanism. [ABSTRACT FROM AUTHOR]

A new azo compound 3 [2-((4-hydroxy-3-(E)-(2-hydroxy-5-nitrophenyl)diazenyl)benzaldehyde] and the azo-Schiff derivative 4 [2-((4-hydroxy-3-((E)-(2-hydroxy-5-nitrophenyl)diazenyl)benzylidene)amino)-4-nitrophenol[ (azo-Schiff 4) have been synthesized. 13C-NMR, 1H-NMR, FT-IR, mass spectroscopy and UV-Vis analysis was used to characterized new compounds. The new synthesized compound azo-Schiff 4 was utilized to inhibit mild steel (MS) corrosion at little concentrations (0.001-0.006 M). Weight loss measurements studies in 1 M HCl and at 298 K showed that azo-Schiff 4 has a good corrosion inhibition efficiency, 75% at 0.002 M of inhibitors. It was found that adsorption methods follow Langmuir isotherm with ΔG values around -23.8 kJ/mol; this confirms that a stable protective film is formed spontaneously during physical adsorption on the mild steel. [ABSTRACT FROM AUTHOR]

In this study, we explored the formation of CuO nanoparticles, NiO nanoflakes, and CuO-NiO nanocomposites using saponin extract and a microwave-assisted hydrothermal method. Five green synthetic samples were prepared using aqueous saponin extract and a microwave-assisted hydrothermal procedure at 200 °C for 30 min. The samples were pristine copper oxide (100C), 75% copper oxide–25% nickel oxide (75C25N), 50% copper oxide–50% nickel oxide (50C50N), 25% copper oxide–75% nickel oxide (25C75N), and pristine nickel oxide (100N). The samples were characterized using FT-IR, XRD, XPS, SEM, and TEM. The XRD results showed that copper oxide and nickel oxide formed monoclinic and cubic phases, respectively. The morphology of the samples was useful and consisted of copper oxide nanoparticles and nickel oxide nanoflakes. XPS confirmed the +2 oxidation state of both the copper and nickel ions. Moreover, the optical bandgaps of copper oxide and nickel oxide were determined to be in the range of 1.29–1.6 eV and 3.36–3.63 eV, respectively, and the magnetic property studies showed that the synthesized samples exhibited ferromagnetic and superparamagnetic properties. In addition, the catalytic activity was tested against para-nitrophenol, demonstrating that the catalyst efficiency gradually improved in the presence of CuO. The highest rate constants were obtained for the 100C and 75C25N samples, with catalytic efficiencies of 98.7% and 78.2%, respectively, after 45 min. [ABSTRACT FROM AUTHOR]

A fast and simple dispersive solid phase extraction method is described for nitrophenols determination in water samples by using gas chromatography-nitrogen phosphorous detector. Firstly, the Poly(amidoamine) grafted Fe3O4 magnetic nanoparticles were synthesized in different generations by successive addition of butyl acrylate and ethylenediamine. After characterization, the prepared dendrimer was utilized as an adsorbent for magnetic solid phase extraction of 2-nitrophenol, 3-nitrophenol, and 4-nitrophenol to benefit large number of surface amine interaction sites. The effects of the different parameters influencing the sample preparation efficiency were investigated. The proposed method showed linearity in the ranges of 0.04–700 and 0.05–700 µg/dm3 for nitrophenols. The obtained limits of detection and quantification under optimized conditions were 0.01–0.02 and 0.04–0.05 µg/dm3, respectively. The relative standard deviations (n = 5) were less than 3.8% (at 10 µg/dm3). Moreover, the calculated enrichment factors were above 200. In addition, the relative recoveries for a spiked river water sample were satisfactory. [ABSTRACT FROM AUTHOR]

Nitrophenols, a versatile intermediate, have been widely used in leather, medicine, chemical synthesis, and other fields. Because these components are widely applied, they can enter the environment through various routes, leading to many hazards and toxicities. There has been a recent surge in the development of simple, rapid, environmentally friendly, and effective techniques for determining these environmental pollutants. This review provides a comprehensive overview of the latest research progress on the pretreatment and analysis methods of nitrophenols since 2017, with a focus on environmental samples. Pretreatment methods include liquid-liquid extraction, solid-phase extraction, dispersive extraction, and microextraction methods. Analysis methods mainly include liquid chromatography-based methods, gas chromatography-based methods, supercritical fluid chromatography. In addition, this review also discusses and compares the advantages/disadvantages and development prospects of different pretreatment and analysis methods to provide a reference for further research.

Gold nanoparticles (AuNPs) with a high specific surface area show efficient activity for the reduction of nitroaromatics. In this study, single-stranded DNA chains (ssDNA, T30, C30 or A30) were used as templates to mediate the formation of AuNPs, and the results demonstrated that the morphologies of the C30-AuNPs or A30-AuNPs had more abundant irregular features than the T30-AuNPs. The catalytic properties and applications of the C30-AuNPs were systematically examined using a reaction model for the reduction of 4-nitrophenol by NaBH4. The effect of different temperatures and pH values on the catalytic activity of C30-AuNPs have been investigated. The C30-AuNPs showed the highest catalytic activity (rate constant kapp = 0.2221 min−1) for the reduction of 4-NP at 35 °C and pH = 7. The conversion of 4-NP to 4-AP using C30-AuNPs followed the Langmuir–Hinshelwood mechanism, which was explained by the principle of promoting electron transfer, i.e. the surface of C30-AuNPs is rich in active sites that promote the process of electron transfer from BH4− to 4-NP, completing the conversion of 4-nitrophenol to 4-aminophenol. Furthermore, the results confirmed that C30-AuNPs were versatile for catalyzing isomers of 4-NP and azo dyes, such as 2-NP, 3-NP, MO, CR and EBT. The results offer new insights into the construction of Au-based catalysts for efficiently removing environmental pollutants. [ABSTRACT FROM AUTHOR]

Nitroaromatic compounds (NACs), which are widely used in pesticides, explosives, dyes, and pharmaceuticals, include nitrobenzene, nitrotoluenes, nitrophenols, and nitrobenzoates. They are also significant industrial pollutants in the environment. These substances, as well as their derivatives, frequently have toxic or mutagenic properties. Wastewater containing nitroaromatic compounds can be effectively managed by using biological treatment methods that are accessible, cost-effective, and environmentally friendly. This review highlights the latest developments in biological treatment systems for removing NACs from wastewater. The large-scale implementation of biological treatment systems will be facilitated by future studies that focus on identifying the best operational methods and that determine how co-pollutants impact the removal of NACs from wastewater. [ABSTRACT FROM AUTHOR]

Nitrophenols has become a significant threat to the ecosystem and the health of the human beings. Photocatalytic degradation is considered to be the utmost competent approach for the amputation of nitroaromatic pollutants. In this research, 2-nitrophenol (MNP), 2,4-dinitrophenols (DNP), and 2,4,6-trinitrophenol or picric acid (PA) are taken for the degradation studies using the photo-Fenton catalyst of synthesized TiO2 nanoparticle modified with biopolymer containing organic and inorganic functionalities. The morphological study reveals the uniformly distributed TiO2 nanoparticles (15 nm) surfaces are encapsulated by the active site-rich chitosan-ligand-copper complex facilitating more absorption and enhancing the photocatalytic activity toward the target molecules. The UV spectra confirm the predominant shifting of absorption peak in the range 305–310 nm which results due to the formation of TiO2-CBGCu nanocomposites. The zeta potential of the synthesized nanocomposites TiO2-CBGCu 5%, TiO2-CBGCu 10%, and TiO2-CBGCu 20% are − 12, − 20, and − 29 mV which reveals that the value increases with the increase in CBGCu content which in turn signifies the more stability in aqueous solution. Amid the prepared nanocomposites, TiO2-CBGCu 10% demonstrates the imperative catalytic performances toward MNP, DNP, and PA pollutants along with the Fenton's reagent at pH 3.0 under visible light and solar light. It shows effective degradation for strong acid PA within 18 min in visible light compared to MNP and DNP due to the presence of more active sites in the synthesized nanocomposites. This work has created awareness about the multifunctional catalyst and the effectiveness of the same has opened a new passage to eliminate nitrophenols from the agonized environment. [ABSTRACT FROM AUTHOR]

Styrene (St), 1,4 vinyl pyridine (4VP) monomers and divinyl benzene (DVB) monomer‐cum‐crosslinker at different molar ratios were subjected to emulsion polymerization in the presence of FeCl2, 6H2O/FeCl3⋅4H2O followed by the treatment with an aqueous ammonia solution to produce several iron oxide nanoparticles (IONs) impregnated crosslinked copolymer composites. The resulting polymer metal nanocomposites (PMNCs) were characterized by FTIR, proton and 13C NMR, UV–visible spectroscopy, XRD, XPS, DLS, magnetic properties, SEM and TEM. The PMNCs were used for batch and column adsorption and photocatalytic degradation of p‐nitrophenol (PNP) from water. The PMNC4 composite prepared with an styrene:4VP molar ratio of 5:1 (16.7 mol% 4VP), 4 wt.% DVB crosslinker and 0.025/0.05 molar ratios of Fe(II)/Fe(III) salts leads to an optimum batch equilibrium adsorption (qe, mg/g)/removal% of 496.36/99.3 PNP from aqueous PNP of concentration 100 mg/L. The same composite showed an equilibrium PNP adsorption (qe) of 114.2 mg/g polymer and a removal% of 26.8 for an inlet feed concentration (Ci, mg/L)/flow rate (Qt, mL/min)/bed height (h, mm) of 100/30/30 in a fixed bed. The PMNC4 polymer showed a photodegradation efficiency of 98% with a 1st order rate constant of 0.029 min−1 after 70 min of degradation of 100 mg/L PNP in solar light. Highlights: Copolymer network of styrene, 4 vinyl pyridine and DVB were synthesized.Iron oxide nanoparticles were introduced into the network in‐situ during synthesis.The metal polymer nanocomposites (PMNCs) were characterized.Synthesis parameters were optimized with respect to batch adsorption of PNP.PMNCs showed excellent fixed bed adsorption and photocatalytic degradation of PNP. [ABSTRACT FROM AUTHOR]

Cyamelurate anions obtained from the hydrolysis of polymeric graphitic carbon nitride were used for the preparation of a water-stable and crystalline coordination polymer based on nickel(II)–cyamelurate. The polymer was prepared and applied as a catalyst for the reduction of 4-nitrophenol to 4-aminophenol in the presence of borohydride under ambient conditions. The catalyst was prepared by a simple and environmentally friendly method in an aqueous medium, and it was completely characterized by a variety of techniques, including FTIR, UV–Vis, XRD, TGA, TEM, and STEM. The obtained catalyst was able to catalyze the reaction of 4-nitrophenol to 4-aminophenol with a good kinetic constant. In addition, the catalyst proved to be significantly robust, maintaining a conversion rate greater than 80% after five minutes of reaction for eight consecutive catalytic cycles. In addition, the catalytic activity of the coordination polymer was much higher than that observed for a homogeneous catalyst based on aqueous Ni2+ ions, suggesting the importance of the structure of the coordination sphere formed by the cyamelurate anions. The results presented here can contribute to the application of other coordination polymers anchored with cyamelurate-like ligands and derivatives, as well as to new catalyst designs based on this coordination site formed by oxygen and nitrogen donor atoms. [ABSTRACT FROM AUTHOR]

Copper nanoparticles (CuNPs) have drawn considerable interest because of recent evidences on greater Surface Enhanced Raman Spectroscopic (SERS) signal enhancing capability, high antibacterial activity and strong catalytic property with regard to the long existing popular silver and gold particles. The existing chemical synthesis methods usually require extensive purification to remove unreacted inorganic reducing agents, like sodium borohydride used to convert Cu2+ ions to Cu0 and it limits direct use of as-prepared materials in biologic systems. Here, we have endeavored to synthesize starch encapsulated CuNPs through radiation chemical approach which is considered to be one of the cleanest routes and involve in-situ generated hydrated electrons to reduce metal ions directly. Presence of large number of hydroxyl groups within starch molecules facilitates complexation of Cu(II) and thereby stabilizes CuNPs. Transmission electron microscopy (TEM) coupled with selected area electron diffraction (SAED) illustrate that particles synthesized at a typical dose of 83.6 kGy are spherical with size of ca. 8 nm having polycrystalline face-centered cubic phase. The observed blue shift of the absorption maximum suggests formation of smaller sized particles with increase in applied radiation dose keeping other parameters same and this is supported by dynamic light scattering (DLS) data. Further, catalytic efficiency of as-synthesized CuNPs was tested by monitoring sodium borohydride mediated catalytic reduction of para-nitrophenol to para-aminophenol and the apparent rate constant (kapp) was estimated as 3 × 10–3 s−1. Thus, as-synthesized CuNPs appears to be better catalyst than the copper nanoparticles synthesized through conventional method for having kapp of about 1.6 × 10–3 s−1. [ABSTRACT FROM AUTHOR]

Transition-metal coordination complexes have attracted wide attention in molecular chemistry, but their applications still confront a tremendous challenge. Herein, a novel silver coordination polymer with a formula of {[Ag9(TIPA)6](NO3)9·12H2O}n (Ag-TIPA) was prepared by a solvothermal reaction of silver nitrate with triangular tris(4-imidazolylphenyl)amine (TIPA). The crystalline molecular structure was determined by single-crystal X-ray diffraction, which showed that each Ag(I) was coordinated with two nitrogen atoms of TIPA ligands. Such Ag-TIPA was used as a catalyst for the photodegradation of ciprofloxacin and 4-nitrophenol under UV-visible light irradiation. The results exhibited excellent photocatalytic performance and reusability due to high structure stability in an acidic, neutral and alkaline environment. The experimental findings and density functional theory calculations revealed that metal–ligand charge transfer in Ag-TIPA extended the absorption range of light and improved the charge transfer properties of TIPA. To further understand the photodegradation process, the intermediates were predicted and analysed through electrostatic potential, orbital weighted dual descriptor, and liquid chromatography-mass spectrometry techniques. Based on these findings, a possible degradation mechanism was proposed. This study provides new insights into the design and synthesis of Ag-based coordination polymers with novel structures, excellent catalytic activity, and good durability. [ABSTRACT FROM AUTHOR]

High levels of unconjugated bilirubin (UB) in serum lead to asymptomatic and neonatal jaundice and brain dysfunctions. Herein, we have reported the detection of UB at as low as 1 μM in an aqueous alkaline medium using a Zn(II) complex. The specificity of the complex has been validated by the HPLC in the concentration window 6–90 μM, which is rare. The sensory response of the probe at physiological pH against nitro explosives developed it as an instant‐acting fluorosensor for picric acid (PA) and 2,4‐dinitrophenol (2,4‐DNP). Spectroscopic titration provided a binding constant of 4×105 M−1 with PA. The naked eye detection was found to be 15 μM. The solid‐state photoluminescent nature of the complex enabled it for PA sensing in the solid phase. Interestingly, the probe remained fluorescent in various volatile and non‐volatile organic solvents. As a result, it can also detect PA and 2,4‐DNP in a wide range of common organic media. NMR studies revealed the coordination of PA, 2,4‐DNP, and UB to the Zn(II) center of the probe, which is responsible for the observed quenching of the probe with the analytes. [ABSTRACT FROM AUTHOR]

Up to the completion of this work of art, palladium nanoparticles had been positioned on the surface of Fe3O4 by using the extract of the Carica papaya Leaf as a stabilizing as well as a suppressing agent. FT-IR, UV–Vis, TEM, XRD, VSM, FESEM, and EDS were used in order to classify the functionalized Pd/Fe3O4 matrix composites. The 4-nitrophenol was degraded with the help of an efficient catalyst provided by a Pd/Fe3O4 nanocomposite that was created (4-NP). In order to evaluate the catalytic activity of the Pd/Fe3O4 nanocomposite in the responses, UV–Vis spectroscopy was used. It is possible to recover it and put it to use six times before the catalytic performance of the substance is considerably affected. [ABSTRACT FROM AUTHOR]

The amino-functionalized SBA-15 silicon carrier (PMO-pr-NH2) was prepared by the one-pot method, and then HKUST-1 functional composites were synthesized by adsorption combined with in-situ preparation technology (HKUST-1@PMO-pr-NH2). A series of characterization techniques were used to analyze composites, such as BET, FTIR, TEM, XPS, TG, SEM, and XRD. The analysis showed that HKUST-1 was successfully prepared in the pores of the PMO-pr-NH2 silicon-based carrier. The catalytic reduction activity and thermal stability of the composite material were investigated using the reaction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP). After 4 cycles, the catalytic performance of the composites was maintained without any obvious change. [ABSTRACT FROM AUTHOR]

Silver‐based nanostructured composites as effective and stable catalysts were successfully designed as the catalyst to reduce the nitrophenols in aqueous solution at room temperature in the presence of NaBH4. The Co3O4‐C composites with regular morphology and adjustable components derived from ZIF‐67 in an air atmosphere at various temperatures (270, 300, and 350 °C) were chosen as a favorable platform to support silver nanoparticles. The acquired silver‐based nanocatalyst (Ag/Co3O4‐C) exhibited excellent catalytic performance towards the hydrogenation of nitrophenols (2‐NP, 3‐NP, and 4‐NP). The calculated rate constant (Kapp) towards the reduction of 4‐NP followed the order: Ag/Co3O4‐C‐300 (0.70 min−1)>Ag/Co3O4‐C‐270 (0.58 min−1)>Ag/Co3O4‐C‐350 (0.46 min−1). Ag/Co3O4‐C‐300 possessed the highest catalytic activity with no induction time during the reaction. What is more, Ag/Co3O4‐C‐300 could reduce 2‐NP and 3‐NP with the rate constant of 0.936 min−1 and 0.391 min−1, respectively. The catalytic activity was higher that many other metal‐based nanocomposites. The excellent catalytic performance was mainly attributed to the abundant active sites on the surface, and the interfacial synergistic effect between Ag and Co3O4‐C, which had a potential driving force for the hydrogenation reaction. In addition, the catalyst remained active even after recirculation experiments. The Ag‐based nanocomposites can be expected to be applied in industrial applications. [ABSTRACT FROM AUTHOR]

Graphitic carbon nitride (g-C3N4) has proved to be a promising heterogeneous photocatalyst in the visible range. It can be used, among others, for the oxidative conversion of environmentally harmful nitrophenols occurring in wastewater. However, its photocatalytic activity needs to be enhanced, which can be achieved by modification with various dopants. In our work, copper-modified g-C3N4 was prepared by ultrasonic impregnation of the pristine g-C3N4 synthesized from thiourea. The morphology, microstructure, and optical properties of the photocatalysts were characterized by XRD, FT-IR, DRS, SEM, XPS, and TEM. DRS analysis indicated a slight change in both the CB and the VB energies of Cu/g-C3N4 compared to those of g-C3N4. The efficiency of the photocatalysts prepared was tested by the degradation of nitrophenols. Copper modification caused a sevenfold increase in the rate of 4-nitrophenol degradation in the presence of H2O2 at pH = 3. This dramatic enhancement can be attributed to the synergistic effect of copper and H2O2 in this photocatalytic system. A minor Fenton reaction role was also detected. The reusability of the Cu/g-C3N4 catalyst was demonstrated through five cycles. Copper-modified g-C3N4 with H2O2 proved to be applicable for efficient visible-light-driven photocatalytic oxidative degradation of nitrophenols. [ABSTRACT FROM AUTHOR]

The advancement of science and technology and the growth of industry have led to an escalating discharge of domestic sewage and industrial wastewater containing dyes. This surge in volume not only incurs higher costs but also exacerbates environmental burdens. However, the benefits of green and reusable catalytic reduction materials within dye processes are still uncertain. Herein, this study utilized the eco-friendly deep eutectic solvent method (DESM) and the chlorite-alkali method (CAM) to prepare a cellulose-composed wood aerogel derived from natural wood for 4-nitrophenol (4-NP) reduction. The life cycle assessment of wood aerogel preparative process showed that the wood aerogel prepared by the one-step DESM method had fewer environmental impacts. The CAM method was used innovatively to make uniform the chemical functional groups of different wood species and various wood maturities. Subsequently, palladium nanoparticles (Pd NPs) were anchored in the skeleton structure of the wood aerogel with the native chemical groups used as a reducing agent to replace external reducing agents, which reduced secondary pollution and prevented the agglomeration of nanoparticles. Results showed that the catalytic reduction efficiency of 4-NP can reach 99.8%, which shows promises for applications in wastewater treatment containing dyes. Moreover, investigation of the advantages of preparation methods of wood aerogel has important implications for helping researchers and producers choose suitable preparation strategies according to demand. [ABSTRACT FROM AUTHOR]

HOCl and UV activated HOCl (UV/HOCl) have been applied for water disinfection and abatement of organic contaminants. However, the production of toxic byproducts in the HOCl and UV/HOCl treatment should be scrutinized. This contribution comparatively investigated the elimination of 4-nitrophenol and the generation of chlorinated byproducts in HOCl and UV/HOCl treatment processes. 61.4% of 4-nitrophenol was removed by UV/HOCl in 5 min with HOCl dose of 60 μM, significantly higher than that by UV (3.3%) or HOCl alone (32.0%). Radical quenching test showed that HO• and Cl• played important roles in UV/HOCl process. 2-Chloro-4-nitrophenol and 2,6-dichloro-4-nitrophenol were generated consecutively in HOCl process; but their formation was less in the UV/HOCl process. Trichloronitromethane (TCNM) was only found in the UV/HOCl process, and its production increased with increasing HOCl dosage. Besides chlorinated products hydroxylated and dinitrated products were also identified in the UV/HOCl process. Transformation pathways involving electrophilic substitution, hydroxylation, and nitration were proposed for 4-nitrophenol transformation in the UV/HOCl process. Wastewater matrix could significantly promote the transformation of 4-nitrophenol to 2-chloro-4-nitrophenol in UV/HOCl process. Results of this study are helpful to advance the understanding of the transformation of nitrophenolic compounds and assess the formation potential of chlorinated byproducts in HOCl and UV/HOCl disinfection processes. [ABSTRACT FROM AUTHOR]

Disubstituted adamantanes having nitrophenol moieties were examined for their ability to recognize ketone and ester molecules through multiple intermolecular interactions, with the hydroxyl and nitro groups serving as hydrogen bond donors and acceptors. Crystallization of 1,3-bis(2-hydroxy-5-nitrophenyl)adamantane (1) in acetone, 2-butanone, and methyl acetate afforded three inclusion crystals with 1 : 1 stoichiometry. X-ray crystallographic analysis revealed that the hydroxyl groups of 1 engaged in OH⋯O interactions with the guest oxygen atoms in all crystals. Moreover, the guest hydrogen atoms participated in CH⋯O interactions with the host nitro and hydroxyl groups at three, four, or five points. These findings suggest that the guest molecules were captured through interactions with multiple functional groups in a manner resembling that of guest inclusion in enzyme pockets. Crystallization of 1,3-bis(4-hydroxy-3-nitrophenyl)adamantane (2) and 1,3-bis(2-ethoxy-5-nitrophenyl)adamantane (3) in acetone resulted in the formation of guest-free crystals, with NO2⋯NO2 interactions being prominent in the crystal of 3. [ABSTRACT FROM AUTHOR]

Hydrothermal preparation was used to create stable luminous sulfur quantum dots (SQDs), and XRD, XPS, TEM, and FTIR analyses were used to assess their structural and morphological characteristics. With an average size of 5.5 2.0 nm, the SQDs had an S8 monoclinic crystal structure. The SQDs' 415 nm excitation-independent emission at an excitation wavelength of 342 nm was discovered by optical characterization. Nitrophenols (4- and 2-nitrophenol) having detection limits of 46 and 171 nM, respectively, were successfully detected using high quantum yield (72%) SQDs. Real sample analysis has been conducted with bottled, tap, and river water. The supporting investigation analyzed the fluorescence quenching mechanism and highlighted the probable static quenching phenomenon. SQDs are also an anti-counterfeiting material because of their high luminescence characteristics and have been successfully used as fluorescent ink. [ABSTRACT FROM AUTHOR]

Ag nanoparticles (Ag NPs) nanocomposites are promising catalysts for nitro compound reduction, but simultaneously meeting the requirements of high catalytic activity, stability, recyclability and facile preparation is highly difficult. Herein, the three‐dimensional (3D) porous magnetic polyaniline (PANI) was synthesized using phytic acid (PA) as the dopant/crosslinker, and a recyclable PANI/Ag NPs nanocomposite (PMPA) was obtained through the in situ redox between PANI and AgNO3. Characterization results demonstrate that PMPA exhibits a typical 3D porous structure constructed by coral‐like PANI framework with well‐dispersed Ag NPs (10–20 nm) firmly anchored. The PMPA can efficiently catalyze the 4‐nitrophenol (4‐NP) reduction, with a reaction rate constant of 9.5 × 10−3 s−1 (and 1067.4 s−1 g−1), which is highly competitive to the previously reported high‐performance Ag NPs catalysts. This is probably due to the favorable mass/electron conduction of 3D porous structure and strong interaction between PA and Ag. Moreover, the magnetism renders PMPA recyclability via a simple magnetic attraction, and the reaction rate constant remains at a high level after six reuse cycles, up to 4.8 × 10−3 s−1. This work highlights the important role of 3D porous PANI in structure of Ag NPs nanocomposites, and paves a new way to develop recyclable catalysts with facile preparation and high catalytic performance. Highlights: Facile synthesis via in situ reaction between 3D porous PANI and AgNO3.Stable dispersion and strong anchor attributed to phytic acid.Conductive porous structure to facilitate mass/electron transportation.Outstanding catalytic performance for 4‐NP reduction and recycle by magnetism. [ABSTRACT FROM AUTHOR]

In this work, degradation and mineralization of para‐nitrophenol in the aqueous medium by a mixture of two strong oxidants of persulfate and periodate have been studied. To this aim, a photo‐reactor with a volume of 1 L has been used. Optimization and modeling of the process was performed by the response surface methodology. According to the prediction of the model, the process has an ability to remove para‐nitrophenol up to 91.6% in the optimal conditions of para‐nitrophenol initial concentration of 15 mg/L, [KPS] = 50 mg/L, [KPI] = 49.7 mg/L, and pH = 5 after 40 min. Assessment of the mineralization of para‐nitrophenol under optimal conditions showed an efficiency of about 57%, while parallel processes alone (UV and UV/KPS and UV/KPI) showed lower mineralization efficiency. Also, the kinetic study showed that the results were fitted with a pseudo‐first‐order equation with a regression coefficient of 0.97 and rate constant of 0.052 (L/min). Moreover, the electrical energy consumption for the process was calculated as 110.77 (kWh/m3) in the optimum condition. In general, the results of this work showed that the use of the homogeneous hybrid AOP methods increases the efficiency of the mineralization. [ABSTRACT FROM AUTHOR]

The development of facile luminescent sensors for detecting nitrophenols in aqueous media is of great necessity for the safety of the environment and human health, as they are a class of widespread toxic organic pollutants that cause serious adverse effects upon consumption. Based on a new multidentate asymmetric ligand (H2L) in which salicylamide and 4-nitryl-salicylaldimine are spaced by 1,2-bis(2-ethoxy)ethyl, a new hydrostable lanthanide intercycle, [Tb2L2(NO3)2]·CH3CN (Tb-[2]c), was prepared to act as a new luminescent sensor for 4-NP in water media. Structural analysis indicated that two fully deprotonated L2− ligands in cis-configuration and μ2-L-κ2O1:κO2:κO4:κN2:κO5 coordination mode were interlocked by two TbIII ions to render the emitted TbIII encapsulated by L2− for lessening non-radiative transitions. The excellent sensitizing capability of the ligand L2− to TbIII was ascertained by both experimental methods and theoretical calculations. The sensing exploration indicated that Tb-[2]c exhibited highly sensitive and selective recognition of 4-NP against other nitroaromatics in aqueous media. The recognition mechanism could be attributed to the internal filtration effect (IFE) mechanism when DFT calculations and accumulating experimental evidence were combined. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) are peculiar multimodal materials that find photocatalytic applications for the decomposition of lethal molecules present in the wastewater. In this investigation, two new d10-configuration-based MOFs, [Zn2(L)(H2O)(bbi)] (1) and [Cd2(L)(bbi)] (2) (5,5-(1,4-phenylenebis(methyleneoxy)diisophthalic acid (H2L) and 1,1′-(1,4-butanediyl)bis(imidazole) (bbi)), have been synthesized and characterized. The MOF 1 displayed a (4,6)-connected (3.43.52)(32.44.52.66.7) network topology, while 2 had a (3,10)-connected network with a Schläfli symbol of (410.511.622.72)(43)2. These MOFs have been employed as photocatalysts to photodegrade nitrophenolic compounds, especially p-nitrophenol (PNP). The photocatalysis studies reveal that 1 displayed relatively better photocatalytic performance than 2. Further, the photocatalytic efficacy of 1 has been assessed by altering the initial PNP concentration and photocatalyst dosage, which suggest that at 80 ppm PNP concentration and at its 50 mg concentration the MOF 1 can photo-decompose around 90.01% of PNP in 50 min. Further, radical scavenging experiments reveal that holes present over 1 and ·OH radicals collectively catalyze the photodecomposition of PNP. In addition, utilizing density of states (DOS) calculations and Hirshfeld surface analyses, a plausible photocatalysis mechanism for nitrophenol degradation has been postulated. [ABSTRACT FROM AUTHOR]

Stannous chloride dihydrate (SnCl2.2H2O) is an inexpensive and commonly used reagent for nitro group reduction. We observed partial O‐demethylation or O‐debenzylation of O‐alkylated nitrobenzene derivatives when subjected to the nitro reduction with the reagent in ethyl acetate at heating, a generally employed reaction condition. A neat reaction at 80 °C afforded the debenzylated product. Reactions at room temperature yielded corresponding O‐alkylated anilines only. The results show the effect of electron‐withdrawing groups on dealkylation; when at the ortho or para position to the alkoxy group, they enhanced the possibility of dealkylation, and no dealkylation was observed in meta‐oriented substrates. The systematic study may help researchers to choose the proper conditions to prevent undesired products. [ABSTRACT FROM AUTHOR]

The biosynthesis of palladium nanoparticles supported on microbial cells (bio-Pd) has attracted much recent interest, but the effect of solution chemistry on the process remains poorly understood. Biological buffers can be used to maintain physiological pH during the bioreduction of Pd(II) to Pd(0) by microbial cells, however, buffer components have the potential to complex Pd(II), and this may affect the subsequent microbe-metal interaction. In this study, a range of Pd(II) salts and biological buffers were selected to assess the impact of the solution chemistry on the rate of bioreduction of Pd(II) by Geobacter sulfurreducens, and the resulting biogenic palladium nanoparticles. The different buffer and Pd(II) combinations resulted in changes in the dominant Pd(II) species in solution, and this affected the amount of palladium recovered from solution by the microbial cells. The physical properties of the bio-Pd nanoparticles were altered under different solution chemistries; only slight variations were observed in the mean particle size (<6 nm), but significant variations in particle agglomeration, the extent of Pd(II) bioreduction and subsequent catalytic activity for the reduction of 4-nitrophenol (4-NP) were observed. The combination of sodium tetrachloropalladate and bicarbonate buffer resulted in bio-Pd with the smallest mean particle size, and the fastest initial rate of reaction for 4-NP reduction (0.33 min-1). Other solution chemistries appeared to damage the cells and result in bio-Pd with relatively poor catalytic performance. This work emphasises that future studies into bio-Pd synthesis should consider the importance of solution chemistry in controlling the speciation of Pd(II) and its impact on both the bioreduction process and the resulting properties of the nanoparticles produced, in order to maximise Pd(II) biorecovery and optimise catalytic properties. [ABSTRACT FROM AUTHOR]

Humans are exposed to various bisphenols, alkylphenols and nitrophenols through dietary intake, food packaging and container materials, indoor and outdoor air/dust. This study aimed to evaluate exposure of Japanese pregnant women to environmental phenols by measuring target compounds in urine samples. From a cohort of the Japan Environment and Children’s Study, 4577 pregnant women were selected. Bisphenol A (BPA), bisphenol S (BPS), bisphenol F (BPF), bisphenol AF (BPAF), para-nitrophenol (PNP), 3-methyl-4-nitrophenol (PNMC), branched 4-nonylphenol (4-NP), linear 4-nonylphenol and 4-tert-octylphenol (4-t-OP) were analysed using a high-performance liquid chromatograph coupled to a triple-quadrupole mass spectrometer. The urinary metabolite data were combined with a questionnaire to examine the determinants of phenol exposure by machine learning. The estimated daily intake (EDI) and hazard quotient (HQ) of BPA were calculated. PNP (68.2%) and BPA (71.5%) had the highest detection frequencies, with median concentrations of 0.76 and 0.46 μg/g creatinine, respectively. PNMC, BPS, BPF and 4-NP were determined in 24.9%, 11.9%, 1.3% and 0.4% of samples, respectively, whereas BPAF (0.02%) and 4-t-OP (0.02%) were only determined in a few samples. The PNP concentrations measured in this study were comparable with those reported in previous studies, whereas the BPA concentrations were lower than those reported previously worldwide. The EDI of BPA was 0.014 μg/kg body weight/day. Compared with the tolerable daily intake set by the German Federal Institute for Risk Assessment, the median (95th percentile) HQ was 0.044 (0.2). This indicates that the observed levels of BPA exposure pose a negligible health risk to Japanese pregnant women. Determinants of bisphenol and nitrophenol exposure could not be identified by analysing the questionnaire solely, suggesting that biological measurement is necessary to assess exposure of pregnant women to bisphenols and nitrophenols. This is the first study to report environmental phenol exposure of Japanese pregnant women on a nationwide scale.

This work presents a comprehensive analysis of the adsorption of selected aromatic organic compounds on activated carbons. Both the equilibrium and kinetics of adsorption were studied using UV–Vis spectrophotometry. The influence of a number of factors: pH, contact time, presence of an accompanying substance, adsorbate concentration, as well as the mass and size of adsorbent grains, on the adsorption process from aqueous solutions was investigated. Phenol, 2-nitrophenol, 3-nitrophenol, 4-nitrophenol and methylene blue (as an accompanying substance) were selected as adsorbates. GAC 1240W and RIAA activated carbons were used as adsorbents. The equilibrium data were analyzed using the generalized Langmuir isotherm equation (R2 = 0.912–0.996). Adsorption rate data were fitted using a multi-exponential kinetic equation (1 − R2 = (1.0 × 10−6)–(8.2 × 10−4)). As an additional parameter, the half-time was also used to present the influence of selected factors on the adsorption kinetics. An increase in the amount of adsorption was demonstrated with increasing contact time as well as with decreasing solution pH and adsorbent grain size. For selected systems, an increase in the adsorption rate was observed with increasing adsorbate concentration, adsorbent mass and at lower pH values. In some cases, the presence of an accompanying substance also resulted in an increase in adsorption kinetics. In the tested experimental systems, optimal conditions for adsorption were established (T = 298 K, pH = 2, contact time: 7 days, grain diameter: >0.5 mm and the ratio of the mass of the adsorbent to the volume of the adsorbate solution: 1 g/L). Additionally, the acid–base properties (potentiometric titration), morphology (SEM) and structure (TEM) of the used adsorbents were also examined.

Nitrophenols, which are defined as an important toxic and carcinogenic pollutant in agricultural and industrial wastewater due to their solubility in water, form of resistance against all organisms in water resources. It is vital that these compounds, which are highly toxic as well as highly explosive, are removed from the aquatic ecosystem. In this paper, we reported the preparation and advanced characterization of Pd0 nanoparticles supported over hydroxyapatite nanospheres (Pd0@nano-HAp). The catalytic efficiency of the Pd0@nano-HAp catalyst was examined in the reduction of nitrophenols in water in the presence of NaBH4 as reducing agent and the great activity of catalyst have been specified against 2-nitrophenol, 4-nitrophenol, 2,4-dinitrophenol and 2,4,6-trinitrophenol compounds with 70.6, 82.4, 27.6 and 41.4 min−1 TOFinitial values, respectively. Another important point is that the Pd0@nano-HAp catalyst has perfect reusability performance (at 5th reuse between 68.5 and 92.8 %) for the reduction of nitrophenols. In addition, catalytic studies were carried out at different temperatures in order to determine thermodynamic parameters such as Ea, ΔH≠ and ΔS≠.

Three nitrophenols are among the 126 priority toxic pollutants identified by the US Environmental Protection Agency. Catalyzing hydrogenation is a simple way to convert these toxic nitrophenols into harmless aminophenols. Commercial PdC has excellent catalytic hydrogenation activity but has weaknesses such as high price and low reusability. Here, we fabricated a series of nano-Pd 2D Co-MOF heterostructures and filtered for optimal Co-MOF@Pd0.0012, which contain ultra-low Pd content (0.08 wt%) and recorded high catalytic efficiency for 4-nitrophenol among the reported non-single atom catalyst due to edge and size effects. The TOF value of Co-MOF@Pd0.0012 is 9800 h−1, ∼206 times higher than that of PdC (Pd content, 10 wt%). Furthermore, Co-MOF@Pd0.0012 has been widely applied to catalyze the reduction of various nitrophenol substrates with higher than 99% conversion efficiency and selectivity. [ABSTRACT FROM AUTHOR]

In the present research, we aimed to develop a simple and green approach to producing a very versatile Ag@AgCl/Fe3O4@kaolinite bionanocomposite with the aid of the aqueous extract of Melissa officinalis. In fact, the Ag@AgCl sample, biosynthesized using the extract, was upgraded with imprinting on kaolinite to produce the Ag@AgCl/kaolinite bionanocomposite. Likewise, we synthesized the four-component Ag@AgCl/Fe3O4@kaolinite for promoting the properties and applications of the as-made nanocomposites. The products were characterized using various techniques such as UV–Vis, FT-IR, XRD, FE-SEM, EDX and XPS. Moreover, they were utilized not only as the efficient heterogeneous catalysts for the reduction of para-nitrophenol to para-aminophenol, but also as the useful biosensors for the detection of Hg2+ in the aqueous media. The resulting heterogeneous catalysts, thus, featured valuable advantages like easier work-up, better stability, and greater separation ability using an external magnet. [ABSTRACT FROM AUTHOR]

With the rapid development of population and technology, many pollutants are released into the environment. It is very crucial to protect the environment as well as human health. In this work, Iron oxide nanoparticles (IONPs) were synthesized by hydrothermal method and loaded into the chitosan salicylamide copper complex (CSC), the final sample was characterized by XRD, UV–Vis, FTIR, and SEM–EDX techniques. From the XRD analysis, the crystal structure was studied and the average particle size of the IONP was measured to be 18.79 nm. The UV–Vis was used to determine the presence of IONP by appearing corresponding intense peaks, it was also used to determine the energy gap value 2.1 eV for the IONP by the Tauc's relation. FTIR spectrum determines the presence of Fe–O bond by appearing stretching frequencies at 538 cm−1 and 627 cm−1 and also confirms the presence of CSC by appearing relative stretching frequencies. The SEM graph has shown spherical morphology and uniform distribution of IONPs. The experimental study of photocatalytic degradation of nitrophenols was repeated within the time interval of 60 min at different light sources (UV-254 nm, UV-365 nm, UV-395 nm, Visible light, and Sunlight), at different pH values (2.5, 7 and 10.5) and different AOP techniques. Here, the AOP techniques are photocatalytic experiments with prepared photocatalyst (PC), photocatalyst combined with Fenton's reagent (PFC) and, only with Fenton's reagent (F). It is observed that the photocatalytic degradation of three nitrophenols reached 100% within 30 min under sunlight with PFC at a pH value of 2.5. [ABSTRACT FROM AUTHOR]

Highly active catalysts remain a vital issue for the Fenton-like degradation of polychlorinated phenols by H2O2. To this question, Cu0-Fe3O4 nanocatalysts functionalized with hydroxyl and carboxyl groups were prepared in this paper, and the Cu0-Fe3O4-H2O2 Fenton-like system was constructed and investigated for the degradation of chlorophenols. The results showed that Cu0 could greatly improve the oxidation activity of the system. 0.04 g Cu0-Fe3O4 composite (Fe/Cu = 3/1 mol/mol) could activate 20 μL H2O2 (30%) degrade near 100% DCP or 2,4,6-TCP or nitrophenol in 100 mL solution in the concentration of 50 mg/L within 1–5 min under initial pH 3.0–8.0, 25 °C. The Cu0-Fe3O4-H2O2 system showed high activity and broad pH applicability which was mainly due to the improved Fe(III)/Fe(II) cycle by Cu0, the reduced redox potential of Fe(III)/Fe(II) by functionalized group, and the adsorption ability of Cu0-Fe3O4 nanocomposites on chlorophenols. The degradation of 2,4-DCP was a combination of oxidative and reductive processes. About 86.6% was oxidized and 13.4% was reduced during the degradation. This study provides a potential method for quickly removing phenolic pollutants. [ABSTRACT FROM AUTHOR]

Using the sonochemical method, nano-plates of a 3D Zn(II) metal−organic framework (MOF) were synthesized and characterized using FT-IR spectroscopy and PXRD. The effect of various irradiation durations and concentrations of reagents was investigated to obtain uniform morphologies. Increasing the irradiation time along with decreasing the reagent concentration led to the production the particles with a uniform nano-plate morphology. Also, the sensing potential of these nano-plates to detect nitroaromatic analytes such as nitrophenol, 2,4-dinitrophenol, and TNP was explored. The nano Zn MOF was highly selective and sensitive in the detection of nitroaromatic derivatives. The quenching percentages of fluorescence emissions for a 2ppb concentration of nitrophenol, 2,4-dinitrophenol, and TNP were 11%, 42%, and 89%, respectively. According to the results, the MOF has the strongest detection limit for TNP. [ABSTRACT FROM AUTHOR]

In the present work, we present the preparation of a new emerged heterogeneous catalyst (PE/g-C3N4/CuO) by in situ deposition of copper oxide nanoparticles (CuO) over the graphitic carbon nitride (g-C3N4) as the active catalyst and polyester (PE) fabric as the inert support. The synthesized sample (PE/g-C3N4/CuO) "dip catalyst" was studied by using various analytical techniques (Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy and dispersive X-ray spectroscopy (SEM/EDX), and transmission electron microscopy (TEM). The nanocomposite is utilized as heterogeneous catalysts for the 4-nitrophenol reduction in the presence of NaBH4, in aqueous solutions. According to experimental results, PE/g-C3N4/CuO with a surface of 6 cm2 (3 cm × 2 cm) demonstrated the catalyst exhibit excellent catalytic activity with 95% reduction efficiency for only 4 min of reaction and an apparent reaction rate constant (Kapp) of 0.8027 min−1. Further evidence that this catalyst based on prepared PE support can be a good contender for long-lasting chemical catalysis comes from the remarkable stability after 10 repetitions reaction cycles without a noticeably loss in catalytic activity. The novelty of this work consists to fabricate of catalyst based of CuO nanoparticles stabilized with g-C3N4 on the surface of an inert substrate PE, which results in an heterogenous dip-catalyst that can be easily introduced and isolated from the reaction solution with good retention of high catalytic performance in the reduction of 4-nitrophenol. [ABSTRACT FROM AUTHOR]

Herein, a novel polyaniline‐co‐polyindole functionalized magnetic porous carbon derived from MIL‐53(Fe) was prepared and employed as an excellent nano‐adsorbent to preconcentrate trace amounts of nitro‐phenols in water and wastewater samples. Briefly, magnetic MIL‐53(Fe) was synthesized by the addition of magnetite nanoparticles, terephthalic acid, and FeCl3 to the reaction medium. The magnetic MIL‐53(Fe) was pyrolyzed under nitrogen protection to obtain a magnetic porous carbon nanocomposite, and finally, the nanomaterial was functionalized with polyaniline‐co‐polyindole via oxidation polymerization. The obtained nano‐adsorbent was characterized via X‐ray diffraction, Fourier‐transform infrared spectroscopy, vibrating sample magnetometry, and transmission and scanning electron microscopies. After that, the fabricated nano‐material was utilized as an excellent nano‐adsorbent for the preconcentration of trace nitro‐phenols (2‐nitrophenol, 4‐nitrophenol, and 2,4‐dinitrophenol) in environmental water, and wastewater samples. The detection limits were obtained from 0.1 to 0.15 μg/L after performing the optimization process. The new method was in the range of 0.4–300 μg/L. The proposed method exhibited a good precision from 3.2% to 9.6% for within‐day assay, and 5.2%–13.2% for between‐day assay at three concentration levels (1, 50, and 250 μg/L). Eventually, this method was utilized to preconcentrate/determine the target analytes in three water, and wastewater samples, satisfactory (relative standard deviations, 5.4%–9.3%; relative recovery, 88%–109%). [ABSTRACT FROM AUTHOR]