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Heterogeneous Fenton-like catalysis mediated by solid catalyst is a promising oxidation technology for water purification. The redox reactivity, cost-effectiveness, and environmental compatibility of solid catalyst play governing roles in oxidant activation, radical generation, and pollutant degradation. Herein, the surface-disordered WO3 (D-WO3) functionally engineered by the unique crystalline-amorphous core–shell structure is proven to be a superior solid catalyst of heterogeneous Fenton-like catalysis for peroxymonosulfate (PMS) activation and pollutant degradation in various water matrices. Six typical phenolic and dye pollutants are effectively and selectively degraded in the D-WO3/PMS system with much reduced matrix effects. Both radical identifying and scavenging tests elucidate the important role of non-radical 1O2 and mediated electron transfer during PMS activation on the D-WO3 surface. The superior Fenton-like activity of D-WO3 can be mainly attributed to the surface and sub-surface distorted lattice sites with finely tailored atomic and electronic structures and surface chemistry. These distorted lattice sites can thermodynamically serve as the key reactive centers of dissociative adsorption and catalytic activation for both PMS and pollutant, with high adsorption energy, strong structural activation, and smooth electron transfer. Our findings provide a new chance for heterogeneous Fenton-like catalysis mediated by transition metal oxides with high capacity, low cost, and no toxicity for promising water purification.

Using the waste basalt powder, ferric chloride (FeCl3·6H2O), ferrous sulfate (FeSO4·7H2O), 3-aminotrimethoxysilane (3-TMSPT) and Chitosan (CTS) as raw materials, through hydrothermal synthesis, in-situ synthesis, cross-linking and grafting methods, the amino-modified chitosan/magnetic zeolite composite (NH2-CTS/MZ) was prepared. The samples were characterized by SEM, XRD, VSM, BET, FTIR and XPS. The removal ability and adsorption mechanism of U(VI) in an aqueous solution by NH2-CTS/MZ were systematically studied. The results showed that under the conditions of 308 K and pH = 5, NH2-CTS/MZ reached adsorption equilibrium within 180 min, and the equilibrium adsorption capacity was 749.5 mg·g−1. The adsorption isotherm conforms to the Langmuir isotherm model (R2 = 0.998), and the adsorption kinetics conforms to the quasi-secondary kinetic model (R2 = 0.987). The adsorption behaviour is a spontaneous endothermic process. This study shows that NH2-CTS/MZ has a good application prospect in the removal of uranyl ions.

Magnetic carbon aerogels were prepared from inexpensive and readily available winter melon to adsorb U(VI). The morphology, structure, magnetism, characteristic functional groups and chemical bonds of magnetic carbon aerogels were characterized by TEM, SEM, XRD, BET, VSM, FT-IR, XPS. Under the condition of 303 K and pH 6, magnetic carbon aerogel reached adsorption equilibrium within 120 min, with the adsorption capacity of 230.3 mg g–1, much higher than that of carbon aerogel (77.9 mg g–1), which is the function of Fe–O. The good magnetism of magnetic carbon aerogels allows it to be easily separated from the solution by applying magnetic field. The adsorption isotherm data accord with Langmuir isothermal model. Adsorption is a spontaneous and endothermic process.

Photochemical oxidation is able to effectively regenerate the fouled electrode in electrochemical pollutant monitoring, while its regeneration capacity is limited by the surface-bound hydroxyl radical speciation with low activity and mobility, which is attributed to the dissociated water adsorption on hydrophilic metal oxides. In this work, fluorine-terminated {001}-exposed TiO2 single crystals (F-TiO2) are rationally designed to construct an Au-based electrochemical sensor (Au/F-TiO2) for dopamine (DA) detection in different matrices. The Au/F-TiO2 sensor exhibits an efficient and stable detection capacity in both environmental and biological samples. A superior photochemical regeneration capacity is obtained on the Au/F-TiO2 electrode with much reduced matrix effects under UV irradiation. Spectral observation, crystallographic analysis, pollutant degradation performance, radical inhibition, and surface enhanced Raman scattering tests reveal that both the fluorine-terminated surface chemical features and the bulk-free radical speciation are mainly responsible for the superior photochemical regeneration capacity of the Au/F-TiO2 electrode. Even for the real biological samples, a stable electrochemical DA detection is also achieved on the Au/F-TiO2 sensor. Our work establishes a new approach to refine electrochemical sensors for stable monitoring and provides a robust photoactive electrode substrate with high efficiency and low cost for practical applications.

Heterogeneous catalysis is promising for water treatment. Solid catalysts play governing roles. Herein, the surface-disordered WO3, D-WO3, engineered with surface and sub-surface defective sites from NaBH4 reduction was proven to be an effective catalyst for H2O2 activation. The defective degree and defects amount on WO3 were regulated by NaBH4. More than 95% of two typical azo dyes, RhB and MG, were selectively degraded in D-WO3/H2O2 system during 3.0 h, while no significant activity was observed for MO as well as bisphenol A, roxarsone, phenol, 4-chlorophenol, p-nitrophenol, o-aminophenol, urea, and 2,4-dichlorophenol in comparison under the identical conditions (mainly less than 20%). Both ESR and radical scavenging tests indicated the minor role of ·OH from H2O2 activation on D-WO3. The superior activity of D-WO3 could be mainly attributed to the surface and sub-surface defects with finely tailored local atomic configurations and electronic structures of central metal sites. Surface and sub-surface defective sites could serve as the reactive sites of interfacial adsorption, dissociative activation, and catalytic decomposition for both oxidant and pollutants, with high adsorption energy, strong structural activation, and superior catalytic activity. Our findings provided a new chance for non-selective radical catalysis based on transition metal oxides and a promising catalyst with high performance, low cost, and no toxicity for pollutant degradation with weak matrix effects in wastewater and surface water.

This article has been retracted, and the online PDF has been watermarked “RETRACTION”. The retraction notice is available at http://doi.org/10.3233/MGC-220954.

Bisphenol A (BPA) is a semi-persistent environmental endocrine disrupter and widely present in aqueous environments. Electrochemical detection is an effective method to monitor pollutants like BPA in aqueous environments. However, the electrode fouling from anodic polymeric products is one main barrier of electrochemical sensors for their practical applications. In this work, a renewable electrochemical sensor was rationally designed, constructed and tested for efficient BPA detection. The TiO2 anodic material was surface-engineered by inorganic-framework molecular imprinting sites with tailored morphological shape, exposed facet and crystal structure. This electrode could be activated mainly as an electrochemical catalyst and partially as a photochemical catalyst. The developed TiO2-based sensor exhibited a good detection reliability and cyclic stability for determining BPA in water samples, with an electrochemical signal decrease of less than 5.0% in 10-run cyclic tests. By virtue of the bi-functional properties of the tailored TiO2 anodic material, a unique photo-assisted electrochemical sensor was further developed, in which analyte digestion and analytical signal originated mainly from anodic conversion. Such a synergistic digesting mechanism distinguishes it from the reported electro-assisted photochemical TiO2 sensors. Our work provides a robust sensor for monitoring pollutants in aqueous environments and a new opportunity to develop renewable electrode materials with good reusability.

The electrode is the key in electrochemical process for water and wastewater treatment. Many nonstoichiometric metal oxides are active electrode materials but have poor stability under strong anodic polarization due to their susceptible nature of the oxygen vacancies on surface and subsurface as defective reactive sites. In this work, a novel photochemical protecting strategy is proposed to stabilize the defective reactive sites on the TiO2- x surface and subsurface for long-term anodic oxidation of pollutants. With this strategy, a novel photoassisted electrochemical system at low anodic bias is further constructed. Such a system exhibits a high protecting capacity at a low operation cost for electrochemical degradation of bisphenol A (BPA), a typical persistent organic pollutant. Its excellent photochemical protecting capacity is found to be mainly attributed to the mild non-band-gap excitation pathways on the defective TiO2- x electrode under both visible-light irradiation and moderate anodic polarization. Under real sunlight irradiation, a 20 run cyclic test for BPA degradation demonstrates the excellent performance and stability of the constructed system at low bias without significant oxygen evolution. Our work provides a new opportunity to utilize the defective and reactive TiO2- x for efficient, stable, and cost-effective electrochemical water treatment with the aid of its photo- and electrochemical bifunctional properties.

Sulfate radical (SO4 −) based oxidation is an efficient and selective strategy for environmental decontamination. Herein, we confirmed, for the first time, that the fine modulation on semiconducting TiO2 was able to improve the redox-cycling capability for heterogeneous peroxydisulfate (PDS, S2O82−) activation and radicals generation. PDS activation by defective TiO2−x exposed by high-energy {0 0 1} polar facets was a superior Fenton-like catalytic system for rhodamine B (RhB) and bisphenol A (BPA) degradation, with good activity and selectivity under neutral pH. By radical inhibiting tests with two different scavengers, fluorescence measurements with terephthalic acid and electron paramagnetic resonance (EPR) technique, only the SO4 − was identified to be the main reactive species from PDS activation on defective TiO2−x for pollutants degradation. Compared to the reported TiO2−x/H2O2 system, the proposed TiO2−x/PDS system exhibited much lower water matrix effects in the presence of four typical anions, natural organic matters and real surface water for target pollutants degradation. The selective SO4 −-mediated TiO2−x/PDS catalytic system in natural water matrix and the no toxicity of catalytic material were of considerable interest for practical environmental applications with highly complex chemistry. Our findings elucidated a new strategy for efficient and selective PDS activation based on the defect-related chemistry, which can degrade environmental contaminants and remedy contaminated soil based on sulfate components with much reduced matrix effects.

Mg–Al, Zn–Al and Mg–Fe magnetic layered double hydroxide (LDH) adsorbents were synthesized. The adsorption effect and influencing factors of these adsorbents were explored, and the adsorption mechanism of phosphorus was studied with advanced instruments. The results showed that the best adsorption performance was observed when the molar ratio of metals was 3 for the magnetic LDH adsorbents, and the maximum adsorption amount for phosphorus was 74.8, 80.8 and 67.8 mg/g for Mg–Al, Zn–Al and Mg–Fe LDHs, respectively. Pseudo-second-order kinetics could be used to describe the adsorption process of phosphorus onto the magnetic LDHs. The adsorption of phosphorus onto the magnetic LDHs was an exothermic process. Lower temperatures were favourable for adsorption, and the adsorption of phosphorus onto the magnetic LDHs was a spontaneous process. When the solid–liquid ratios were 0.10 g/L, 0.10 g/L and 0.05 g/L for Mg–Al, Zn–Al and Mg–Fe magnetic LDHs, respectively, the highest adsorption amount of phosphorus was achieved for each magnetic LDH. The maximum adsorption amount was observed at pH values of 6.0–8.0. The inhibitory effect of HCO3− on the adsorption capacity of phosphorus onto the magnetic LDHs was the strongest at a higher HCO3− concentration level. The relative content of –OH significantly reduced after adsorption of phosphorus by the FTIR analysis, which indicated that the mechanism of phosphorus removal was mainly through the exchange between hydroxyl on the adsorbent surface and phosphorus in water. XPS studies showed that oxygen provided electrons during the adsorption of phosphorus.

Organic Fenton-like catalysis has been recently developed for water purification, but redox-active compounds have to be ex situ added as oxidant activators, causing secondary pollution problem. Electrochemical oxidation is widely used for pollutant degradation, but suffers from severe electrode fouling caused by high-resistance polymeric intermediates. Herein, we develop an in situ organic Fenton-like catalysis by using the redox-active polymeric intermediates, e.g., benzoquinone, hydroquinone, and quinhydrone, generated in electrochemical pollutant oxidation as H(2)O(2) activators. By taking phenol as a target pollutant, we demonstrate that the in situ organic Fenton-like catalysis not only improves pollutant degradation, but also refreshes working electrode with a better catalytic stability. Both (1)O(2) nonradical and ·OH radical are generated in the anodic phenol conversion in the in situ organic Fenton-like catalysis. Our findings might provide a new opportunity to develop a simple, efficient, and cost-effective strategy for electrochemical water purification.

Glabridin, a compound of the flavonoid, has shown outstanding skin-whitening and anti-aging properties, but its water insolubility limits its wide application. Therefore, glabridin liposome (GL) has been developed to improve its poor bioavailability, while there are few studies to evaluate its amelioration of UVB- induced photoaging. This study is performed to investigate the amelioration of GL against UVB- induced cutaneous photoaging. The prepared GL has a spheroidal morphology with an average diameter of 200 nm. The GL shows lower cytotoxicity than glabridin, but it has a more effective role in inhibition of melanin. Moreover, the application of GL can effectively relieve UV radiation induced erythema and leathery skin, associated with the down-regulated expression of inflammatory cytokines (TNF-α, IL-6 and IL-10). Taken together, these results demonstrate that GL has potentials as topical therapeutic agents against UVB radiation induced skin damage through inhibiting inflammation.

Utilising the general waste such as non-burning brick as raw materials to prepare low-cost zeolite is in line with the green chemical industry and can achieve the purpose of treating waste with waste. Here we use the abandoned non-burning brick powder as raw material, the sulfhydryl functionalized magnetic zeolite composites (MZ-SH) were prepared by combining a series of methods such as hydrothermal synthesis, high temperature melting magnetization, and grafting technology. The samples were characterized by SEM, EDS, XRD, XPS, and FT-IR. The adsorption behavior of MZ-SH on uranyl ions was systematically studied. The results show that the equilibrium adsorption capacity of MZ-SH to uranium(VI) ions was 1285.86 mg/g under the optimal adsorption conditions with t of 270 mins, T at 35 ℃, C0 being 35 mg/L, pH at 6.0, and m by 0.025 g/L. Its adsorption isotherm complies with the Langmuir adsorption model, while the adsorption kinetics conforms to the quasi-second-order adsorption kinetic model. The adsorption type is mainly chemical adsorption with type of monolayer distribution on the surface. Adsorption thermodynamics shows that the adsorption process was spontaneous at 25–45 ℃. FT-IR and XPS analysis showed that sulfhydryl, –OH, Al-O and Si-O played an important role in the adsorption process of uranium (VI) ions by MZ-SH. It indicates that the uranium(VI) ions prefer binding with –OH and sulfhydryl groups and there is also showing ion exchange between uranium(VI) ions and Al-O and Si-O groups.

Organoarsenicals are widely used as antibiotics in the livestock industry and largely discharged into water environment directly, their safe, efficient and cost-effective treatment are actively perused. Herein, a heterogeneous iron-based Fenton-like technology was designed and validated with much reduced secondary pollution, mainly attributed to the bi-functional properties of both Fenton-active and arsenic-affinitive iron oxides. This simple one-step strategy not only exhaustively degraded organoarsenicals, but also selectively adsorbed the released high-toxicity arsenic from treated water. With Roxarsone as target, the FeOOH-based Fenton-like system exhibited a much superior capacitie for both Roxarsone degradation and arsenic adsorption in various water matrices, compared to typical homogeneous systems under similar conditions. More than 80% of Roxarsone was degraded after 3.0 h, and most of the released AsO43− was removed simultaneously, without any additional post-treatment. The superior capacity of FeOOH might be mainly attributed to its strong redox-cycling capacity of surface central Fe atoms from their thermodynamically favorable electronic structure. Taking the important advantages of iron oxides and Fenton technology into account, our findings might provide a new chance to develop simple and efficient technologies for organoarsenicals removal from water with much reduced secondary pollution at a low cost.

Noble metals, nanostructured carbon, and their hybrids are widely used for electrochemical detection of persistent organic pollutants. However, despite of the rapid detection process and high accuracy, these materials generally suffer from high costs, metallic impurity, heterogeneity, irreversible adsorption and poor sensitivity. Herein, the high-energy {001}-exposed TiO2 single crystals with specific inorganic-framework molecular recognition ability was prepared as the electrode material to detect bisphenol A (BPA), a typical and widely present organic pollutant in the environment. The oxidation peak current was linearly correlated to the BPA concentration from 10.0 nM to 20.0 μM (R2 = 0.9987), with a low detection limit of 3.0 nM (S/N = 3). Furthermore, it exhibited excellent discriminating ability, high anti-interference capacity, and good long-term stability. Its good performance for BPA detection in real environmental samples, including tap water, lake and river waters, domestic wastewater, and munic...

Co3O4-mediated heterogeneous activation of peroxymonosulfate (PMS) is an efficient strategy to generate sulfate radicals for environmental pollutants degradation. The rate-limiting step is Co OH− complex formation, and it highly depends on the thermodynamic capacity of water dissociation to generate surface hydroxyl groups. Herein, for efficient PMS activation and pollutants degradation, the water dissociation capacity of TiO2, a promising Co3O4 support, was facilely refined by its shape-tailored synthesis with dominant high-energy {0 0 1} facet. The polar {0 0 1} facet is characterized by a high density of atomic steps, edges and kinks of the low-coordinate surface atoms with a large number of dangling bonds, all of which can serve as reactive sites for water adsorption and dissociation and thus improve Co OH− complex formation dynamics in sulfate radical formation. Co3O4 deposited on TiO2-{0 0 1} exhibited a much higher PMS activation capacity and pollutants degradation efficiency, i.e. p-nitrophenol and rhodamine B, and a much lower Co2+ leaching. This superiority could be mainly attributed to the strong Ti5c-centered water adsorption and dissociation, the high density of surface hydroxyl groups, the robust Co OH− complex generation and the intimate catalyst-support interactions. Our findings might provide a new chance to refine Co-mediated sulfate radical generation and other Fenton-like systems for advanced water treatment with reduced secondary pollution.

Visible-light-driven photocatalysis is a promising technology for advanced water treatment, but it usually exhibits a low efficiency. Cu2O is a low-cost semiconductor with narrow band gap, high absorption coefficient and suitable conduction band, but suffers from low charge mobility, poor quantum yield and weak catalytic performance. Herein, the Cu2O catalytic capacity for refractory pollutants degradation is drastically improved by a simple and effective strategy. By virtue of the synergistic effects between photocatalysis and Fenton, a novel and efficient photocatalysis-driven Fenton system, PFC, is originally proposed and experimentally validated using Cu2O/Nano-C hybrids. The synergistic PFC is highly Nano-C-dependent and exhibits a significant superiority for the removal of rhodamine B and p-nitrophenol, two typical refractory pollutants in wastewater. The PFC superiority is mainly attributed to: (1) the rapid photo-electron transfer driven by Schottky-like junction, (2) the selective O2 reduction mediated by semi-metallic Nano-C for efficient H2O2 generation, (3) the specific H2O2 activation and large OH generation catalyzed by Haber-Weiss Fenton mechanism, and (4) the accelerated Fe2+/Fe3+ cycling and robust Fe2+ regeneration via two additional pathways. Our findings might provide a new chance to overcome the intrinsic challenges of both photocatalysis and Fenton, as well as develop novel technology for advanced water treatment.

A cross sectional study to observe the relation between body mass index (BMI) and the fasting total blood cholesterol level was carried out among 82 undergraduate medical students from SEGi University, Kota Damansara. The participants were randomly selected to participate in this research. The BMI was then calculated by using the standard formula (kg/m). The fasting total blood cholesterol level was measured by using home cholesterol kit. The obtained data was then analyzed by using statistical package for the social sciences software (version 22.0). For males, the highest mean BMI value and highest mean fasting total blood cholesterol level were recorded for Indian students followed by Malays and Chinese. There was significant correlation between BMI and the fasting total blood cholesterol level in male participants (0.001, r-value = 0.525). As for females, Malays had the highest mean BMI value followed by Indians and Chinese and the highest mean fasting total blood cholesterol level was found in Chinese followed by Malays and Indians. No significant correlation was found between BMI and fasting total blood cholesterol levels in female participants (0.922, r-value = 0.015). However, there was a significant correlation between BMI and fasting total blood cholesterol level in overall male and female participants (0.015, r-value = 0.267). In conclusion, our study suggests that the students should be advised to exercise more; reduce intake of food with high cholesterol, avoid fast food and have an active and healthy lifestyle. This may overall improve their health status and prevent them from getting diseases which are associated with obesity and high cholesterol level.

The heterogeneous catalyst plays a key role in Fenton-like reaction for advanced oxidation of refractory pollutants in water treatment. Titanium dioxide (TiO2) is a typical semiconductor with high industrial importance due to its earth abundance, low cost and no toxicity. In this work, it is found that TiO2 can heterogeneously activate hydrogen peroxide (H2O2, E° = 1.78 eV), a common chemical oxidant, to efficiently generate highly-powerful hydroxyl radical, OH (E0 = 2.80 eV), for advanced water treatment, when its crystal shape, exposed facet and oxygen-stoichiometry are finely tuned. The defect-engineered TiO2 single crystals exposed by high-energy {0 0 1} facets exhibited an excellent Fenton-like activity and stability for degrading typical refractory organic pollutants such as methyl orange and p-nitrophenol. Its defect-centered Fenton-like superiority is mainly attributed to the crystal oxygen-vacancy, single-crystalline structure and exposed polar {0 0 1} facet. Our findings could provide new chance to utilize TiO2 for Fenton-like technology, and develop novel heterogeneous catalyst for advanced water treatment.

TiO2 is a typical semiconductor and has been extensively used as an effective photocatalyst for environmental pollution control. But it could not be used as an electrochemical reductive catalyst because of its low electric conductivity and electrocatalytic activity. In this work, however, we demonstrate that TiO2 can act as an excellent cathodic electrocatalyst when its crystal shape, exposed facet and oxygen-stoichiometry are finely tailored by the local geometric and electronic structures. The defect-engineered TiO2-x single crystals dominantly exposed by high-energy {001} facets exhibits a high cathodic activity and great stability for electrochemical reduction of nitrobenzene, a typical refractory pollutant with high toxicity in environment. The single crystalline structure, the high-energy {001} facet and the defective oxygen vacancy of the defect-engineered TiO2-x single crystals are found to be mainly responsible for their cathodic superiority. With the findings in this work, a more practical non-Pd cathodic electrocatalyst could be prepared and applied for electrocatalytic reduction of refractory pollutants in water and wastewater, and extend the promising applications of TiO2 in the fields of environmental science.

Photocatalyst plays a vital role in the photochemical water treatment. To improve the visible-light photoactivity of TiO2 for refractory pollutant degradation, CdS/TiO2 hybrids with different nanostructures have been prepared, but usually suffer from a low photocatalytic degradation efficiency and a rapid photocorrosion. In this work, we developed a synergistic ZnO/CdS/TiO2 hybrid, which could act as a robust and self-protected photocatalyst for water purification without additional sacrificial reagents. This was attributed to the two different junction mechanisms in one single hybrid. Photons were selectively adsorbed by ZnO and CdS, then, the electrons with a low reductive activity in ZnO recombined directly with the holes with a low oxidative activity in CdS, whereas the holes with a high oxidative activity in ZnO and the electrons with a high reductive activity in CdS were captured for catalytic reaction. The superiority of the novel ZnO/CdS/TiO2 hybrid over the traditional CdS/TiO2 hybrid in both photocatalytic activity and anti-photocorrosion capacity was demonstrated in the degradation of Atrazine and Rhodamine B, two typical refractory organic pollutants, and the treatment of real textile wastewater under solar light irradiation. The developed ZnO/CdS/TiO2 hybrid exhibited an excellent potential for the degradation of refractory pollutants, and provided a new way to advance intrinsically solar-susceptible catalyst for photochemical wastewater treatment.

Photochemical oxidation based on semiconducting metal oxides is an efficient strategy to remove environmental pollutants in water, air and soil. The fine manipulation of photo-carriers separation, surface chemistry and radical speciation is of considerable interest for environmental remediation. In this work, the morphology- and structure-tailored TiO2 single crystals with epitaxial {101}/{001} facet junction were designed, prepared and tested for photochemical pollutant oxidation in the presence of organic arsenicals, the main component in swine wastewater from livestock industry, although they have been forbidden for several years. The facet junction-tailored TiO2 deserved an efficient photo-carriers separation with high quantum efficiency. The photochemical oxidation of 4-chlorophenol (4-CP), phenol and bisphenol A (BPA) was substantially improved by roxarsone (ROX). ROX-enhanced photochemical activity of TiO2 was mainly attributed to the in-situ arsenic-terminated surface chemistry by Ti-OAsVO3/-OAsIIIO2. This surface played governing roles in water/TiO2 interactions, and changed water adsorption from dissociative to molecular configuration. Furthermore, ·OH was finely regulated from low-activity surface-bound to high-activity bulk-free speciation between as-generated photo-holes with free water molecules. Our findings provided a new chance to refine the TiO2-based photochemical oxidation, and a modifying technology to treat swine wastewater from livestock industry with much reduced secondary pollution.

Mitochondrial dysfunction can drive cellular senescence, which is accompanied by changes in metabolism and increases in senescence-associated secretory phenotypes. Although pyruvate, a key metabolite for numerous aspects of metabolism, has been used as general supplement in synthetic media, the physiological function of pyruvate underlying its protective role against cellular senescence under normal conditions has remained unknown. Here, we show that extracellular pyruvate prevents senescence in normal human dermal fibroblasts through increasing the generation of oxidized nicotinamide adenine dinucleotide (NAD+) during the conversion to lactate. Acetylated peroxisome proliferator-activated receptor gamma coactivator 1α (PGC-1α), vacuolar-type H+-ATPaseV0A1 (v-ATPaseV0A1), NF-κB p65 subunit (RelA), and histone H3 accumulate under pyruvate deprivation conditions, resulting in the onset of senescence in normal human dermal fibroblasts through the accumulation of abnormal mitochondria generated by lysosomal inactivation-induced mitophagy defects, and through an increase in senescence-associated secretory phenotypes. Furthermore, pyruvate showed a protective effect against aging phenotypes in skin equivalents, which consist of a dermis and epidermis that act similarly to in vivo skin tissues. Our findings reveal a connection between pyruvate and mitochondrial dysfunction in the progression of senescence that is, to our knowledge, previously unreported. These results suggest that the pyruvate deprivation-induced senescence model can be used to study the connection between metabolism and senescence under normal conditions.

Anodization has been reported to be an effective electrochemical method to prepare vertically ordered, upright oriented TiO2 nanotubes for efficient photocatalysis, solar cells and many other fields. However, this process generates a large amount of residual anodic electrolytes that are rich in toxic fluorides, which are usually discarded and cause environmental contamination. Here, we propose a facile and effective method to prepare both pristine and N-doped TiO2 nanocrystals based on the recycling of waste ethylene glycol electrolyte from the widely-used anodic process. Under identical conditions, both the pristine and N-doped TiO2 nanocrystals exhibited nearly twice as high photocatalytic activity in decomposition of humic acids and bentazone than Degussa P25, one of the best commercial TiO2 photocatalysts. The preparation method had obvious economic and environmental benefits. The prepared TiO2 nanocrystals possessed superior photocatalytic degradation capacities for refractory pollutants, and could be used for efficient water treatment.

Understanding the relationships between the molecular structure and electronic transport characteristics of single-molecule junctions is of fundamental and technological importance for future molecular electronics. Herein, we report a combined experimental and theoretical study on the single-molecule conductance of a series of oligo(phenylene ethynylene) (OPE) molecular wires, which consist of two phenyl-ethynyl-phenyl π units with different dihedral angles. The molecular conductance was studied by scanning tunneling microscopy (STM)-based break-junction techniques under different conditions, including variable temperature and bias potential, which suggested that a coherent tunneling mechanism takes place in the OPE molecular wires with a length of 2.5 nm. The conductance of OPE molecular junctions are strongly affected by the coupling strength between the two π systems, which can be tuned by controlling their intramolecular conformation. A cos(2)θ dependence was revealed between the molecular conductance and dihedral angles between the two conjugated units. Theoretical investigations on the basis of density functional theory and nonequilibrium Green's functions (NEGF) gave consistent results with the experimental observations and provided insights into the conformation-dominated molecular conductance.

The cathodic material plays an essential role in oxygen reduction reaction for energy conversion and storage systems. Titanium dioxide, as a semiconductor material, is usually not recognized as an efficient oxygen reduction electrocatalyst owning to its low conductivity and poor reactivity. Here we demonstrate that nano-structured titanium dioxide, self-doped by oxygen vacancies and selectively exposed with the high-energy {001} facets, exhibits a surprisingly competitive oxygen reduction activity, excellent durability and superior tolerance to methanol. Combining the electrochemical tests with density-functional calculations, we elucidate the defect-centred oxygen reduction reaction mechanism for the superiority of the reductive {001}-TiO2−x nanocrystals. Our findings may provide an opportunity to develop a simple, efficient, cost-effective and promising catalyst for oxygen reduction reaction in energy conversion and storage technologies., Titanium dioxide is not generally considered to be an effective oxygen reduction catalyst. Here, the authors show that nanostructured titanium dioxide, self-doped with oxygen vacancies and with exposed high-energy {001} facets, exhibits competitive oxygen reduction catalytic activity and durability.

The paper presents a study of renovation of aerial aluminum alloy (LY12CZ) by laser melt casting with Al matrix composite powder. The microstructure of the melt casting zone was investigated, and the fatigue contrast test was carried out between the repaired specimens and the undamaged specimens. It is found that the melt casting zone consists of equiaxed crystals and columnar crystals. The equiaxed crystals distribute in the deposited layer and the crystal size is about 3~4μm. The columnar crystals whose axial direction size comes to 30μm~40μm exist near the interface with its crystallographic axis perpendicular to the interface. The fatigue life of specimens repaired by laser melt casting was shorter than no-damage specimens to a large extant, because of the flaws in the deposited layer engendered the origins of cracks; the columnar shape grains at the bottom of casting zone were easy to split under the tensile stress; the residual stress after the melt casting accelerated the initiation and growth of the cracks.

To explore reaction mechanisms and proper effects of aluminium in laser micro-molton pool, experiments of laser cladding (Ti+1-8%Al) on Ti-6Al-4V by pulsed Nd:YAG had been carried out. The microstructures, microhardness and phases of the cladding layers with different weight percentage of Al were investigated. The content of Al was quantitatively determinated when ordering α2 ceramic phase (Ti3Al matrix) were formed. And the friction and wear properties of the cladding layers were examined in atmosphere. It was found that the microstructure of the cladding layers included cellular crystals, columnar crystals, arborescent crystals and dispersive white granules. The α2 ceramic phase was formed when the content of Al was 6%wt. With the increasing of weight percentage of Al, the number and size of arborescent crystals increased obviously, as well as the microhardness, the maximum was 957.9Hv, 1.3-1.5 times of the layers with below 6%wt Al. Inversely, the wear resistance of the laser cladding layers was improved gradually. Friction coefficient, wear extent and wear rate decreased. 0.55-0.7 times of the layers with below 6%wt Al.

Soy hypocotyls, the byproduct from soy protein industry, rich in isoflavones, was attempted to develop into a value-added functional food, soy protein isolate (SPI). Soy hypocotyls were defatted by supercritical CO 2 (SC-CO 2 ) under the following conditions as 35 MPa, 2 h, 45 °C with a constant flow rate of CO 2 at 5 l/min, fed from the bottom of the extraction vessel. Via extraction, the oil contents were lowered from 10.5 g/100 g in original soy hypocotyls to 0.2 g/100 g in defatted soy hypocotyls (DSH) with a Protein Dispersibility Index (PDI) value of 91.2 that contained about 2.18 g/100 g of isoflavones and 63.6 g/100 g of proteins. SPI was then extracted from DSH under the optimized conditions including: the pH of water solution at 6, the ratio of DSH to water solution as 1:10 and the extraction temperature at 30 °C with the extraction time of 30 min. The freeze-dried SPI contained 92.46 g/100 g of the proteins and 640 mg/100 g of isoflavones, where the three major β -glycosides, glycitin, daidzin and genistin accounted for about 83.7% of the total isoflavones. The yields of SPI and isoflavones were about 48% and 30% in terms of their respective total contents in DSH.

OBJECTIVE: The failure of dysmotility to explain the symptoms of pain in irritable bowel syndrome (IBS) led to studies on visceral hypersensitivity. Mucosal mast cells (MC) may be one factor influencing the response of visceral afferents to mechanical and chemical stimuli because they are found in close proximity to gastrointestinal mucosal sensory nerve terminals containing neuropeptides and a bi-directional pathway linking the central nervous system, gut and MC has been demonstrated. METHODS: The present study investigated the extent of MC and the neuropeptides, substance P (SP) and vasoactive intestinal peptide (VIP), in the intestinal mucosa of patients with IBS, as well as the location of the MC. The MC and neuropeptidergic terminals were stained histochemically and immunohistochemically, respectively, neuropeptide concentrations were measured by radioimmunoassay (RIA), and the results were investigated qualitatively and quantitatively by color image analyzer. The structural relation between the MC and neuropeptide terminals was studied by ultramicroscopy using in situ embedding technique. RESULTS: In IBS, the number of MC in the terminal ileum, the ileocecal junction, and the ascending colon was significantly increased (P

Anodic material plays a vital role in electrochemical water treatment. Titanium dioxide (TiO2) has been widely recognized as an excellent semiconductor photocatalyst, rather than an efficient electrocatalyst, due to its relatively low electric conductivity and poor electrochemical activity. In this work, it is found that TiO2 can actually become a superior electrocatalyst when its crystal shape and exposed facet are finely tuned. The shape-engineered TiO2 single crystals with {001} facets exhibit an excellent electro-catalytic activity and stability for degrading typical organic pollutants such as rhodamine B and bisphenol A, and treating complex landfill leachate. Its electro-catalytic superiority is mainly attributed to the single-crystalline structure and exposed polar {001} facet. Our findings could provide new possibility of utilizing TiO2 for efficient electrochemical water treatment because of its high activity, great stability, low cost and no toxicity.

Metal sulfide semiconductors, such as molybdenum disulfide (MoS2) and bismuth trisulphide (Bi2S3), are of considerable interest for their excellent applications in photocatalysis and in many other fields. However, the controllable synthesis of MoS2/Bi2S3 hybrid nanostructures remains a challenge. In this study, we report a unique sacrificial templating strategy for preparing layer-controlled MoS2 on three-dimensional (3D) Bi2S3 micro-flowers. For this approach, Bi2S3 was utilized as a sacrificial template to regulate the ion exchange, and the dosage of molybdenum was adjusted to tune the dynamic formation, thus converting the MoS2 nanosheets on the Bi2S3 micro-flowers from monolayer to multilayer. Such a 3D flower-like hybrid nanostructure enables MoS2/Bi2S3 to exhibit adsorption-promoted photocatalysis under visible light irradiation, especially for the excellent photodegradation of low-concentration organic pollutants, for example, azo dye and atrazine. The observed superiority of the 3D MoS2/Bi2S3 was mainly attributed to the increased mass transfer, robust light-harvesting capacity, improved charge separation, lower oxygen-activation barrier and enhanced active oxygen yield. Our findings are of interest for the development of novel S-based photocatalysts and provide a new opportunity to efficiently remove low-concentration refractory pollutants. Researchers have combined inorganic ‘microflowers’ and metallic nanosheets to help remove persistent organic pollutants with sunlight. Bismuth trisulphide (Bi2S3) is a promising environmental photocatalyst because of its low toxicity and direct bandgap, but suffers from lower-than-expected chemical activity due to charge recombination. To better separate photogenerated charges, Han-Qing Yu and co-workers from the University of Science and Technology of China developed a one-pot, hydrothermal synthesis that transforms bismuth precursors into three-dimensional (3D) microstructures with petal-like shapes. The Bi2S3 microflowers then act as a template, growing multilayers of MoS2 onto the hybrid framework. The large, charge-stabilizing surface area of 3D MoS2/Bi2S3 had promising photocatalytic activity. For example, concentrations of atrazine — a common weed-killer difficult to remove from water runoff streams — were 89% lower after 4 hours of exposure to light and 3D MoS2/Bi2S3. A sacrificial strategy is developed for preparing layer-controlled MoS2 on three-dimensional Bi2S3 micro-flowers using a facile method. The nanostructured hybrid enables adsorption-promoted photocatalysis under visible light irradiation for excellent degradation of low-concentration organic pollutants, because of the increased mass transfer, robust light-harvesting capacity, improved charge separation, reduced oxygen-activation barrier and enhanced active oxygen yield.

Beta-D-glucosidase-catalyzed deglucosidation of phenylpropanoid amides of 5-hydroxytryptamine (PAHAs) glucoside in safflower (Carthamus tinctorius L.) seed extracts, including N-(p-coumaroyl)serotonin glucoside (CSG) and N-feruloylserotonin glucoside (FSG), was optimized by response surface methodology (RSM). The Box-Behken design (BBD) was employed to evaluate the interactive effects of independent variables on the deglucosidation rates of CSG and FSG. The variables involved were pH (5.6-6.2), temperature (45-55 degrees C), and enzyme load (2.0-3.0%, relative to the weight of the total substrate). The substrate concentration was fixed at 3.3 g/L on the basis of factorial experiments. The optimum conditions obtained via RSM at a fixed time of 2 h were as follows: pH, 5.9; temperature, 48 degrees C; and enzyme load, 3.0%. Under these conditions, the actual deglucosidation rates of CSG and FSG were 75.5 and 42.2%, respectively, which agree well with the predicted values (75.3 and 41.9%) by RSM. The final incubation time (10 h) was determined by the time course of the deglucosidation under the above-mentioned optimum conditions, which gave the deglucosidation rates of both CSG and FSG above 90%. Simultaneously, 2-hydroxyarctiin, a typical cathartic beta-glucoside, was also removed by 80.3%.

A systematic research on the electron deposition process in the JAEA 10 A ion source is carried out by using a particle-in-cell/Monte Carlo collision simulation, which is based on a full three-dimensional self-developed code. Two parts are studied. One is the space and energy distribution of fast and slow electrons, the other is the vibration excitation collisions between electrons and hydrogen moleculars. The results show that the inhomogeneity of electrons comes from the Y direction drift of the fast electrons (Te ≥ 25 eV) due to the action of the magnetic fields. This drift also increases the number of vibration excitation collisions in the —Y direction, and results in the increase of Ha in the —Y direction, eventually leading to the —Y drift of H−. It explains the spatial non-uniformity in the JAEA 10 A ion source.