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Polylactic acid (PLA) has attracted increasing interest as a sustainable plastic because it can be degraded into CO2 and H2O in nature. However, this process is sluggish, and even worse, it is a CO2‐emitting and carbon resource waste process. Therefore, it is highly urgent to develop a novel strategy for recycling post‐consumer PLA to achieve a circular plastic economy. Herein, we report a one‐pot photoreforming route for the efficient and selective amination of PLA waste into value‐added alanine using CoP/CdS catalysts under mild conditions. Results show the alanine production rate can reach up to 2.4 mmol gcat−1 h−1, with a high selectivity (>75 %) and excellent stability. Time‐resolved transient absorption spectra (TAS) reveal that CoP can rapidly extract photogenerated electrons from CdS to accelerate proton reduction, favoring hole‐dominated PLA oxidation to coproduce alanine. This study offers an appealing way for upcycling PLA waste and creates new opportunities for green synthesis of amino acids. [ABSTRACT FROM AUTHOR]

Solar hydrogen production at a high efficiency holds the significant importance in the age of energy crisis, while the micro‐environment manipulation of active sites on photocatalysts plays a profound role in enhancing the catalytic performance. In this work, a series of well‐defined single‐site Ni‐grafted TiO2 photocatalysts with unique and specific coordination environments, 2,2′‐bipyridine‐Ni−O−TiO2 (T−Ni Bpy) and 2‐Phenylpyridine‐Ni−O−TiO2 (T−Ni Phpy), were constructed with the methods of surface organometallic chemistry combined with surface ligand exchange for visible‐light‐induced photocatalytic hydrogen evolution reaction (HER). A prominent rate of 33.82 μmol ⋅ g−1 ⋅ h−1 and a turnover frequency of 0.451 h−1 for Ni are achieved over the optimal catalyst T−Ni Bpy for HER, 260‐fold higher than those of Ni−O−TiO2. Fewer electrons trapped oxygen vacancies and a larger portion of long‐lived photogenerated electrons (>3 ns, ~52.9 %), which were demonstrated by the electron paramagnetic resonance and femtosecond transient IR absorption, correspond to the photocatalytic HER activity over the T−Ni Bpy. The number of long‐lived free electrons injected from the Ni photoabsorber to the conduction band of TiO2 is one of the determining factors for achieving the excellent HER activity. [ABSTRACT FROM AUTHOR]

Photocatalytic generation of •OH from O3 is an intriguing avenue for aqueous organics degradation due to the high utilization of photogenerated electrons, but ambiguous information about charge transfer and surface‐active sites hinders the optimization of photocatalysts. In this work, a series of cobalt single‐atom catalysts (SACs) anchored on graphitic carbon nitride to improve •OH generation from O3 via electron reduction and catalytic activation dual pathway is synthesized. Various characterization and density functional theory calculations reveal that cobalt single atoms can introduce trap states for holes, which improve the light‐harvesting ability and accelerate the transfer of electrons and holes. Meanwhile, Co single atoms can also act as active sites to accelerate ozone decomposition and produce •OH directly. Particularly, the influence of different surface densities of Co single atoms on photogenerated electron supply and surface reaction is disclosed. A higher density of Co provided more active sites for O3 catalytic activation, but the narrowed distance between oxidation and reduction centers reduces the supply of available electrons by worsening the charge recombination. This work offers an atomic‐level correlation of the isolated metal density and photocatalytic properties, and can scientifically guide the design of high‐performance photocatalysts for organic synthesis and water purification. [ABSTRACT FROM AUTHOR]

All‐solid‐state Z‐Scheme photocatalysts have attracted significant attention due to their great potential for solar fuel production. However, delicately coupling two individual semiconductors with a charge shuttle by a material strategy remains a challenge. Herein, we demonstrate a new protocol of natural Z‐Scheme heterostructures by strategically engineering the component and interfacial structure of red mud bauxite waste. Advanced characterizations elucidated that the hydrogen‐induced formation of metallic Fe enabled the effective Z‐Scheme electron transfer from γ‐Fe2O3 to TiO2, leading to the significantly boosted spatial separation of photo‐generated carriers for overall water splitting. To the best of our knowledge, it is the first Z‐Scheme heterojunction based on natural minerals for solar fuel production. Thus our work provides a new avenue toward the utilization of natural minerals for advanced catalysis applications. [ABSTRACT FROM AUTHOR]

Nitrate is an important raw material for chemical fertilizers, but it is industrially manufactured in multiple steps at high temperature and pressure, urgently motivating the design of a green and sustainable strategy for nitrate production. We report the photosynthesis of nitrate from N2 and O2 on commercial TiO2 in a flow reactor under ambient conditions. The TiO2 photocatalyst offered a high nitrate yield of 1.85 μmol h−1 as well as a solar‐to‐nitrate energy conversion efficiency up to 0.13 %. We combined reactivity and in situ Fourier transform infrared spectroscopy to elucidate the mechanism of nitrate formation and unveil the special role of O2 in N≡N bond dissociation. The mechanistic insight into charge‐involved N2 oxidation was further demonstrated by in situ transient absorption spectroscopy and electron paramagnetic resonance. This work exhibits the mechanistic origin of N2 photooxidation and initiates a potential method for triggering inert catalytic reactions. [ABSTRACT FROM AUTHOR]

Objective: The concept of enhanced recovery after surgery (ERAS) has been proposed to provide guidance for the improved postoperative rehabilitation of patients with occipitocervical region disease (ORD). Methods: This study retrospectively investigated 208 consecutive patients (116 men and 92 women) ranging in age from 22 to 76 years with ORD between July 2014 and June 2017 in our medical center, who were divided into three groups that received different preoperative, intraoperative, and postoperative management plans: traditional group (n = 73), ameliorated group (n = 70), and ERAS group (n = 65). We compiled a range of data relating to demographics and postoperative changes in hemoglobin and albumin, surgery duration, intraoperative blood loss, number of postoperative hospitalization days and expenses, readmission rates, and visual analog scale pain symptoms. Data were statistically evaluated using one‐way analysis of variance with Student–Newman–Keuls‐q post hoc tests or chi‐square tests. Results: There were no significant differences in terms of age (P = 0.235), gender (P = 0.691), body mass index (P = 0.723), American Society of Anesthesiologists grade (0.747), lesion character (P = 0.337) and lesion site (P = 0.957) between the three groups. Within a 6 months follow‐up period, there was no significant difference between the three groups in terms of surgery duration (P = 0.225), blood loss (P = 0.172), changes in hemoglobin (P = 0.255) and albumin (P = 0.178). However, postoperative hospitalization days (P = 0.000), postoperative costs (P = 0.019) and improvement of pain symptoms (P = 0.000) in ERAS group were significantly lower or higher than those in traditional group or ameliorated group, respectively. There were 29 (39.73%), 22 (31.43%), and 13 (20.00%), recorded cases of postoperative complications in traditional group, ameliorated group and ERAS group, respectively; complications in ERAS group were significantly lower than those in other two groups (P = 0.043). Moreover, all of the complications were mitigated effectively by the infusion of fluid, analgesia, treatment of infections, or antiemetic medications. There were 2 (2.74%), 3 (4.29%) and 2 (3.08%), recorded cases of re‐admission in traditional group, ameliorated group and ERAS group, respectively, but there were no statistically significant differences when compared across the three groups (P = 0.866). Conclusions: ERAS can provide benefits when it applied to patients undergoing ORD surgery mainly in terms of reducing postoperative complications, however, ERAS does not increase the economic burden of patients or decrease the risk of readmission. [ABSTRACT FROM AUTHOR]

Constructing a high‐quality interface with strong coupling interaction is highly desirable in composite photocatalysts for the efficient interfacial charge transfer. Herein, we prepared black phosphorus quantum dots/CdS (BPQDs/CdS) binary composites with tight interfacial contact via a facile electrostatic self‐assembly approach for efficient photocatalytic H2 evolution. The optimized H2 evolution rate of 3 wt % BPQDs/CdS can reach up to 9.9 mmol g−1 h−1 in lactic acid aqueous solution, 99 and 5.5 times greater than that of pristine BPQDs and CdS, respectively. Benefiting from the strong interface interaction between CdS and BPQDs in well‐contacted BPQDs/CdS composites, efficient charge separation can be achieved, leading to enhanced photocatalytic H2 evolution activity. Notably, the rapid transfer of photogenerated electrons from CdS to BPQDs was unambiguously confirmed by time‐resolved transient absorption spectroscopy. [ABSTRACT FROM AUTHOR]

BACKGROUND 4‐Nitrophenol, as a representative hazardous contaminant, may pose potential risks to the environment in the process of production, storage, and use. Catalytic hydrogenation reduction offers a promising route to the removal of 4‐nitrophenol by its transformation into the less toxic and biodegradable 4‐aminophenol. In this work, nickel−cobalt bimetal oxide nanostructures were fabricated by the thermal decomposition of metal organic frameworks and cooperatively utilized for the catalytic reduction of 4‐nitrophenol. RESULTS: The as‐fabricated oxide catalysts were characterized and analyzed with several physicochemical measurements, including X‐ray diffraction, scanning electron microscopy, transmission electron microscopy, X‐ray photoelectron spectroscopy, thermogravimetry, Fourier‐transform infrared spectroscopy, Raman spectroscopy, nitrogen adsorption, and electrochemical impedance spectroscopy. The catalytic reduction of 4‐nitrophenol was conducted in the presence of the as‐prepared oxide nanostructures with varying Ni/Co ratios to evaluate their catalytic activity. The optimal catalyst (Ni–Co–O) delivered the activity parameter of k'app = 12.0 min−1 mg−1, which was higher than either NiO (2.4 min−1 mg−1) or Co3O4 (3.6 min−1 mg−1). Moreover, the induction time of the 4‐nitrophenol reduction was significantly reduced by using the bimetal oxide catalyst. Based on the surface and electrochemistry analyses, the enhancement of catalytic activity for the Ni–Co bimetal oxide nanostructures was discussed. CONCLUSION: The above results indicated that the cooperation of nickel with cobalt into bimetal oxide nanostructures exhibited an enhanced catalytic activity, which not only promoted the conversion rate of 4‐nitrophenol, but also shortened the reduction induction period. [ABSTRACT FROM AUTHOR]

Cu2O, a low‐cost, visible light responsive semiconductor photocatalyst represents an ideal candidate for visible light driven photocatalytic reduction of N2 to NH3 from the viewpoint of thermodynamics, but it remains unexplored. Reported here is the successful synthesis of uniformly sized and ultrafine Cu2O platelets, with a lateral size of <3 nm, by the in situ topotactic reduction of a CuII‐containing layered double hydroxide with ascorbic acid. The supported ultrafine Cu2O offered excellent performance and stability for the visible light driven photocatalytic reduction of N2 to NH3 (the Cu2O‐mass‐normalized rate as high as 4.10 mmol gCu2O−1 h−1 at λ>400 nm), with the origin of the high activity being long‐lived photoexcited electrons in trap states, an abundance of exposed active sites, and the underlying support structure. This work guides the future design of ultrafine catalysts for NH3 synthesis and other applications. [ABSTRACT FROM AUTHOR]

Loading metal cocatalyst on semiconductor nanoparticles is a general strategy to enhance photocatalytic efficiency, while the consensus of selecting metal cocatalyst matching with semiconductor is still unclear. Herein, we investigated the charge transfer and separation efficiency between ZnO and cocatalysts Ag, Au, and Pt nanoparticles respectively using ultrafast mid‐IR transient absorption spectroscopy. We found that Ohmic contact of Ag with ZnO favoring electron transfer and charge separation, while Schottky junction of Pt or Au with ZnO preventing electron transfer from ZnO to metal. Thus Ohmic contact would be better than Schottky contact. Since photocatalytic efficiency is also determined by chemical catalytic efficiency, we proposed a dual metal cocatalyst strategy for improving the overall photocatalytic efficiency, with the inner metal forming Ohmic contact for efficient charge separation and shuttling electrons and the outer‐layer metal cocatalyst for optimizing the chemical reactivity. [ABSTRACT FROM AUTHOR]

Black phosphorus (BP) has recently drawn attention in photocatalysis for its optical properties. However, limited by the rapid recombination of photogenerated carriers, the use of BP for photocatalytic water splitting still remains a huge challenge. Herein, we prepare a black/red phosphorus (BP/RP) hetero‐phase junction photocatalyst by a wet‐chemistry method to promote the interfacial charge separation and thus achieve Z‐scheme photocatalytic water splitting without using sacrificial agents. The Z‐scheme mechanism was confirmed by time‐resolved transient absorption spectroscopy. This work provides a novel insight into the interface design of hetero‐phase junction with atomic precision. [ABSTRACT FROM AUTHOR]

BACKGROUND Fag t 3 is a major allergenic protein in tartary buckwheat. The Maillard reaction commonly occurs in food processing, but few studies have been conducted on the influence of thermal processing on the allergenic potential of buckwheat allergen. The aim of the present study was to investigate the effects of autologous plant polysaccharides on the immunoreactivity of buckwheat Fag t 3 ( 11S globulin) following the Maillard reaction. RESULTS Fag t 3 and crude polysaccharides were prepared from tartary buckwheat ( Fagopyrum tataricum) flour. After heating, the polysaccharides were covalently linked to Fag t 3 via a Maillard reaction, and the IgE/ IgG-binding properties of Fag t 3 decreased dramatically, with significant changes also being observed in the electrophoretic mobility, secondary structure and solubility of the glycated Fag t 3. The great influence of glycation on IgE/ IgG binding to Fag t 3 was correlated with a significant change in the structure and epitopes of the allergenic protein. These data indicated that conjugation of polysaccharides to Fag t 3 markedly reduced the allergen's immunoreactivity. CONCLUSION Glycation that occurs via the Maillard reaction during the processing of buckwheat food may be an efficient method to reduce Fag t 3 allergenicity. [ABSTRACT FROM AUTHOR]

Three series of bisazo reactive red dyes were synthesised using 6-amino-1-naphthol-3-sulphonic acid and its derivatives as the coupling components. The dyeing parameters and wash fastness of these dyes on knitted cotton were evaluated and the relationships between the structure and dyeing properties were investigated. It was found that the hydrophilic groups introduced into the dye molecules decrease the substantivity and fixation of the dyes, but increase the build-up and migration properties. The defined wash-off factor can directly reflect the wash fastness of the dyes and the build-up property can be improved by commercialisation using certain auxiliaries. The results indicate that there is the possibility of synthesising a red reactive dye with a satisfying balance between high fixation and good wash fastness and several such dyes have been developed. [ABSTRACT FROM AUTHOR]