Tryptophan metabolic pathway plays a key role in the stress-induced emotional eating.

Chronic stress disrupts the emotional and energetic balance, which may lead to abnormal behaviors such as binge eating. This overeating behavior alleviating the negative emotions is called emotional eating, which may exacerbate emotional instability and lead to obesity. It is a complex and multifaceted process that has not yet been fully understood. In this study, we constructed an animal model of chronic mild stress (CMS)-induced emotional eating. The emotional eating mice were treated with tryptophan for 21 days to reveal the key role of tryptophan. Furthermore, serum-targeted metabolomics, immunohistochemical staining, qPCR and ELISA were performed. The results showed that CMS led to the binge eating behavior, accompanied by the disturbed intestinal tryptophan-derived serotonin (5-hydroxytryptamine; 5-HT) metabolic pathways. Then we found that tryptophan supplementation improved depression and anxiety-like behaviors as well as abnormal eating behaviors. Tryptophan supplementation improved the abnormal expression of appetite regulators (e.g., AgRP, OX1R, MC4R), and tryptophan supplementation also increased the tryptophan hydroxylase 2 (tph2) and 5-HT receptors in the hypothalamus of CMS mice, which indicates that the 5-HT metabolic pathway influences feeding behavior. In vitro experiments confirmed that 5-HT supplementation ameliorated corticosterone-induced aberrant expression of appetite regulators, such as AgRP and OX1R, in the hypothalamic cell line. In conclusion, our findings revealed that the tryptophan-derived 5-HT pathway plays an important role in emotional eating, especially in providing targeted therapy for stress-induced obesity.

One-pot solvothermal synthesis of Cu-Fe-MOF for efficiently activating peroxymonosulfate to degrade organic pollutants in water:Effect of electron shuttle.

Persulfate-based advanced oxidation processes (PS-AOPs) show a bright prospect in sewage purification. The development of efficient catalysts with simple preparation process and eco-friendliness is the key for their applying in practical water treatment. Herein, a bimetallic Cu-Fe metal organic framework (MOF) was simply synthesized by using one-pot solvothermal methods and employed for activating peroxymonosulfate (PMS) to degrade organic pollutants in water. The Cu-Fe-MOF/PMS exhibited excellent degradation efficiencies (over 95% in 30 min) for a variety of pollutants, including phenol, bisphenol A, 2,4-dichlorophenol, methyl blue, rhodamine B, tetracycline and sulfamethoxazole. The degradation efficiency was impacted by dosages of Cu-Fe-MOF, PMS concentrations, reaction temperature, solution pH and anionic species. Phenol could be efficiently decomposed in a wide pH range of 5-9, with the highest degradation and mineralization efficiency of nearly 100% and 70%, respectively. Free radicals and non-free radicals participated in degrading of phenol at the same time, with dominantly free radical process, because sulfate radicals (SO4·-) and hydroxyl radicals (·OH) were the primary active substances by contribution calculation. Cu-Fe-MOF was acted as electron shuttle between molecules of phenol and PMS, and the cooperation effect of Fe and Cu on the Cu-Fe-MOF promoted the electron transfer, achieving the high degradation efficiency of phenol. Thus, Cu-Fe-MOF is an ideal catalyst for activating PMS, which is conducive to promote the applying of catalyst-activated PMS processes for practical wastewater treatments.

Polarization-dependent photoinduced metal-insulator transitions in manganites.

In correlated oxides, collaborative manipulation on light intensity, wavelength, pulse duration and polarization has yielded many exotic discoveries, such as phase transitions and novel quantum states. In view of potential optoelectronic applications, tailoring long-lived static properties by light-induced effects is highly desirable. So far, the polarization state of light has rarely been reported as a control parameter for this purpose. Here, we report polarization-dependent metal-to-insulator transition (MIT) in phase-separated manganite thin films, introducing a new degree of freedom to control static MIT. Specifically, we observed giant photoinduced resistance jumps with striking features: (1) a single resistance jump occurs upon a linearly polarized light incident with a chosen polarization angle, and a second resistance jump occurs when the polarization angle changes; (2) the amplitude of the second resistance jump depends sensitively on the actual change of the polarization angles. Linear transmittance measurements reveal that the origin of the above phenomena is closely related to the coexistence of anisotropic micro-domains. Our results represent a first step to utilize light polarization as an active knob to manipulate static phase transitions, pointing towards new pathways for nonvolatile optoelectronic devices and sensors.

Application of advanced oxidation processes for the removal of micro/nanoplastics from water: A review.

Micro/nanoplastics (MNPs) have been increasingly found in environments, food, and organisms, arousing wide public concerns. MNPs may enter food chains through water, posing a threat to human health. Therefore, efficient and environmentally friendly technologies are needed to remove MNPs from contaminated aqueous environments. Advanced oxidation processes (AOPs) produce a vast amount of active species, such as hydroxyl radicals (·OH), known for their strong oxidation capacity. As a result, an increasing number of researchers have focused on using AOPs to decompose and remove MNPs from water. This review summarizes the progress in researches on the removal of MNPs from water by AOPs, including ultraviolet photolysis, ozone oxidation, photocatalysis, Fenton oxidation, electrocatalysis, persulfate oxidation, and plasma oxidation, etc. The removal efficiencies of these AOPs for MNPs in water and the influencing factors are comprehensively analyzed, meanwhile, the oxidation mechanisms and reaction pathways are also discussed in detail. Most AOPs can achieve the degradation of MNPs, mainly manifest as the decrease of particle size and the increase of mass loss, but the mineralization rate is low, thus requiring further optimization for improved performance. Investigating various AOPs is crucial for achieving the complete decomposition of MNPs in water. AOPs will undoubtedly play a vital role in the future for the removal of MNPs from water.

Progress on simultaneous photocatalytic degradation of pollutants and production of clean energy: A review.

In the current era of severe energy and environmental crises, the need for efficient and sustainable methods to control pollution and promote resource recycling has become increasingly important. Photocatalytic degradation of pollutants and simultaneous production of clean energy is one such approach that has garnered significant attention in recent years. The principle of photocatalysis involves the development of efficient photocatalysts and the efficient utilization of solar energy. The use of organic contaminants can enhance the photocatalytic reactions, leading to the sustainable generation of clean energy. Herein, we provide a comprehensive review of the latest advances in the application of photocatalytic synergized clean energy production in the environmental field. This review highlights the latest developments and achievements in this field, highlighting the potential for this approach to revolutionize the way we approach environmental pollution control and resource recycling. The review focuses on (1) the mechanism of photocatalytic degradation and synergistic energy production, (2) photocatalysts and synthesis strategies, (3) photocatalytic carbon dioxide reduction, (4) pollutant degradation, and (5) hydrogen and electricity production. In addition, perspectives on key challenges and opportunities in photocatalysis and clean energy for future developments are proposed. This review provides a roadmap for future research directions and innovations of photocatalysis that could contribute to the development of more sustainable and cleaner energy solutions.

Safety and efficacy of apatinib in patients with advanced gastric or gastroesophageal junction adenocarcinoma after the failure of two or more lines of chemotherapy (AHEAD): a prospective, single-arm, multicenter, phase IV study.

BACKGROUND: Apatinib, a highly selective VEGFR2 inhibitor, significantly improved efficacy versus placebo as a third- and later-line treatment for advanced gastric cancer in phase 2 and 3 trials. This prospective, single-arm, multicenter phase IV AHEAD study was conducted to verify the safety and efficacy of apatinib in patients with advanced or metastatic gastric or gastroesophageal adenocarcinoma after at least two lines of systematic therapy in clinical practice settings. METHODS: Patients with advanced gastric cancer who had previously failed at least two lines of chemotherapy received oral apatinib until disease progression, death or unacceptable toxicity. The primary endpoint was safety. The secondary endpoints included objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS) and overall survival (OS). Adverse events were summarized by the incidence rate. Median OS and PFS were estimated using the Kaplan-Meier method. ORR, DCR, OS at 3 and 6 months, and PFS at 3 and 6 months were calculated, and their 95% CIs were estimated according to the Clopper-Pearson method. RESULTS: Between May 2015 and November 2019, a total of 2004 patients were enrolled, and 1999 patients who received at least one dose of apatinib were assessed for safety. In the safety population, 87.9% of patients experienced treatment-related adverse events (TRAEs), with the most common hypertension (45.2%), proteinuria (26.5%), and white blood cell count decreased (25.3%). Additionally, 51% of patients experienced grade ≥ 3 TRAEs. Fatal TRAEs occurred in 57 (2.9%) patients. No new safety concerns were reported. Among the 2004 patients included in the intention-to-treat population, the ORR was 4.4% (95% CI, 3.6-5.4%), and DCR was 35.8% (95% CI, 33.7-38.0%). The median PFS was 2.7 months (95% CI 2.2-2.8), and the median OS was 5.8 months (95% CI 5.4-6.1). CONCLUSIONS: The findings in the AHEAD study confirmed the acceptable and manageable safety profile and clinical benefit of apatinib in patients with advanced gastric cancer as a third- or later-line of treatment. TRIAL REGISTRATION: This study was registered with ClinicalTrials.gov NCT02426034. Registration date was April 24, 2015.

Effects of Chinese herbal diet on hematopoiesis, immunity, and intestines of mice exposed to different doses of radiation.

Radiotherapy causes a series of side effects in patients with malignant tumors. Polygonati Rhizoma, Achyranthis Bidentatae Radix, and Epimedii Folium are all traditional Chinese herbs with varieties of functions such as anti-radiation and immune regulation. In this study, the above three herbs were used as a herbal diet to study their effects on the hematopoietic, immune, and intestinal systems of mice exposed to three doses of radiation. Our study showed that the diet had no radiation-protective effect on the hematopoietic and immune systems. However, at the radiation dose of 4 Gy and 8 Gy, the diet showed an obvious radiation-protective effect on intestinal crypts. At the dose of 8 Gy, we also found that the Chinese herbal diet had an anti-radiation effect on reducing the loss of the inhibitory nNOS+ neurons in the intestine. That provides a new diet for relieving the symptoms of hyperperistalsis and diarrhea in patients after radiotherapy.

Distinguishing artificial spin ice states using magnetoresistance effect for neuromorphic computing.

Artificial spin ice (ASI) consisting patterned array of nano-magnets with frustrated dipolar interactions offers an excellent platform to study frustrated physics using direct imaging methods. Moreover, ASI often hosts a large number of nearly degenerated and non-volatile spin states that can be used for multi-bit data storage and neuromorphic computing. The realization of the device potential of ASI, however, critically relies on the capability of transport characterization of ASI, which has not been demonstrated so far. Using a tri-axial ASI system as the model system, we demonstrate that transport measurements can be used to distinguish the different spin states of the ASI system. Specifically, by fabricating a tri-layer structure consisting a permalloy base layer, a Cu spacer layer and the tri-axial ASI layer, we clearly resolve different spin states in the tri-axial ASI system using lateral transport measurements. We have further demonstrated that the tri-axial ASI system has all necessary required properties for reservoir computing, including rich spin configurations to store input signals, nonlinear response to input signals, and fading memory effect. The successful transport characterization of ASI opens up the prospect for novel device applications of ASI in multi-bit data storage and neuromorphic computing.

Efficacy, Safety, and Health-Related Quality of Life With Camrelizumab Plus Pemetrexed and Carboplatin as First-Line Treatment for Advanced Nonsquamous NSCLC With Brain Metastases (CAP-BRAIN): A Multicenter, Open-Label, Single-Arm, Phase 2 Study.

INTRODUCTION: Systemic treatment options for NSCLC with brain metastases (BMs) are scarce. We evaluated the activity and safety of camrelizumab plus chemotherapy as first-line therapy in patients with advanced nonsquamous NSCLC with BMs. METHODS: This was a multicenter, single-arm, phase 2 trial (NCT04211090) conducted at seven hospitals in China. Eligible patients had treatment-naive metastatic nonsquamous NSCLC and BMs that were asymptomatic or symptoms controlled with dehydration therapy and no previous systemic treatment or local therapy for the target brain lesion. Patients received camrelizumab (200 mg) plus pemetrexed (500 mg/m2) and carboplatin (area under the curve 5) intravenously on day 1 of each 21-day cycle for four cycles, followed by maintenance with camrelizumab (200 mg) and pemetrexed (500 mg/m2) every 21 days until disease progression, unacceptable toxicity, or death. The primary end point was confirmed intracranial objective response rate according to modified Response Evaluation Criteria in Solid Tumors version 1.1, which was primarily analyzed in the efficacy analysis set (EAS). RESULTS: A total of 45 patients were enrolled and treated (full analysis set), with 40 patients having at least one post-baseline tumor assessment (EAS). As of August 30, 2022, median follow-up duration was 12.5 months (95% confidence interval [CI]: 9.2-17.3). The confirmed intracranial objective response rate was 52.5% (95% CI: 36.1-68.5) in EAS and 46.7% (95% CI: 31.7-62.1) in full analysis set. The extracranial objective response rate was 47.5% (95% CI: 31.5-63.9) and 42.2% (95% CI: 27.7-57.8), respectively. Median intracranial progression-free survival was 7.6 months (95% CI: 4.6-not reached [NR]), median overall progression-free survival was 7.4 months (95% CI: 4.4-NR), and median overall survival was 21.0 months (95% CI: 15.9-NR). The most common treatment-related adverse events of grade 3 or higher were neutrophil count decrease (six [13.3%]) and anemia (four [8.9%]). One treatment-related death occurred owing to immune-related pneumonia. Linear mixed-effects model displayed that a positive trend for improvement in cognitive function and quality of life was observed based on Montreal Cognitive Assessment and Functional Assessment of Cancer Therapy-Lung scores (p = 0.025, p < 0.001). CONCLUSIONS: Camrelizumab plus pemetrexed and carboplatin was found to have an activity with manageable toxicity and to improve cognitive function and quality of life for patients with nonsquamous NSCLC with BMs in the first-line setting.

Anterior Screw Insertion Results in Greater Tibial Tunnel Enlargement Rates after Single-Bundle Anterior Cruciate Ligament Reconstruction than Posterior Insertion: A Retrospective Study.

Background and Objectives: Tunnel enlargement (TE) is a widely reported phenomenon after anterior cruciate ligament reconstruction (ACLR). Given the paucity of knowledge in the literature, it remains unclear whether screw position in the tunnel affects TE. This retrospective cohort study evaluated differences in postoperative tunnel enlargement rates (TER) and clinical results between anterior and posterior tibial interference screw insertion during single-bundle ACLR using autologous hamstring grafts. Materials and Methods: A group of consecutive patients that underwent primary arthroscopic single-bundle ACLR in our hospital were screened and divided into two groups based on the position of the tibial interference screw (determined by Computer Tomography within 3 days after surgery): anterior screw position group (A) and posterior screw position group (B). The bone tunnel size was measured using magnetic resonance imaging (MRI) performed 1 year after surgery. International Knee Documentation Committee (IKDC) score and the Knee Injury and Osteoarthritis Outcome Score (KOOS) were used for clinical results 1 year postoperatively. Results: 87 patients were included. The TER of Group A is higher than that of Group B (43.17% vs. 33.80%, p = 0.024). Group A showed a significant increase (12.1%) in enlargement rates at the joint line level than group B (43.77% vs. 31.67%, p = 0.004). Moreover, KOOS and IKDC scores improved in both groups. There were no significant differences in clinical outcomes between the two groups. Conclusions: One year after ACLR, patients with posterior screw showed significantly lower TE than patients with anterior screw. However, the position of screw did not lead to differences in clinical results over our follow-up period. Posterior screw position in the tibial tunnel maybe a better choice in terms of reducing TE. Whether the different screw positions affect the long-term TE and long-term clinical outcomes needs to be confirmed by further studies.

A preliminary attempt to use radiomic features in the diagnosis of extra-articular long head biceps tendinitis.

BACKGROUND: This study aims to present a radiomic application in diagnosing the long head of biceps (LHB) tendinitis. Moreover, we evaluated whether machine learning-derived radiomic features recognize LHB tendinitis. PATIENTS AND METHODS: A total of 170 patients were reviewed. All LHB tendinitis patients were diagnosed under arthroscopy. Radiomic features were extracted from preoperative magnetic resonance imaging (MRI), and the input dataset was divided into a training set and a test set. For feature selection, the t test and least absolute shrinkage and selection operator (LASSO) methods were used, and random forest (RF) and support vector machine (SVM) were used as machine learning classifiers. The sensitivity, specificity, accuracy, and area under the curve (AUC) of each model's receiver operating characteristic (ROC) curves were calculated to evaluate model performance. RESULTS: In total, 851 radiomic features were extracted, with 109 radiomic features extracted using a t test and 20 radiomic features extracted using the LASSO method. The random forest classifier shows the highest sensitivity, specificity, accuracy, and AUC (0.52, 0.92, 0.73, and 0.72). CONCLUSION: The classifier contract by 20 radiomic features demonstrated a good ability to predict extra-articular LHB tendinitis.However because of poor segmentation reliability, the value of Radiomic in LHB tendinitis still needs to be further explored.

Electronically phase separated nano-network in antiferromagnetic insulating LaMnO3/PrMnO3/CaMnO3 tricolor superlattice.

Strongly correlated materials often exhibit an electronic phase separation (EPS) phenomena whose domain pattern is random in nature. The ability to control the spatial arrangement of the electronic phases at microscopic scales is highly desirable for tailoring their macroscopic properties and/or designing novel electronic devices. Here we report the formation of EPS nanoscale network in a mono-atomically stacked LaMnO3/CaMnO3/PrMnO3 superlattice grown on SrTiO3 (STO) (001) substrate, which is known to have an antiferromagnetic (AFM) insulating ground state. The EPS nano-network is a consequence of an internal strain relaxation triggered by the structural domain formation of the underlying STO substrate at low temperatures. The same nanoscale network pattern can be reproduced upon temperature cycling allowing us to employ different local imaging techniques to directly compare the magnetic and transport state of a single EPS domain. Our results confirm the one-to-one correspondence between ferromagnetic (AFM) to metallic (insulating) state in manganite. It also represents a significant step in a paradigm shift from passively characterizing EPS in strongly correlated systems to actively engaging in its manipulation.

An Improved Density Peak Clustering Algorithm for Multi-Density Data.

Density peak clustering is the latest classic density-based clustering algorithm, which can directly find the cluster center without iteration. The algorithm needs to determine a unique parameter, so the selection of parameters is particularly important. However, for multi-density data, when one parameter cannot satisfy all data, clustering often cannot achieve good results. Moreover, the subjective selection of cluster centers through decision diagrams is often not very convincing, and there are also certain errors. In view of the above problems, in order to achieve better clustering of multi-density data, this paper improves the density peak clustering algorithm. Aiming at the selection of parameter dc, the K-nearest neighbor idea is used to sort the neighbor distance of each data, draw a line graph of the K-nearest neighbor distance, and find the global bifurcation point to divide the data with different densities. Aiming at the selection of cluster centers, the local density and distance of each data point in each data division is found, a γ map is drawn, the average value of the γ height difference is calculated, and through two screenings the largest discontinuity point is found to automatically determine the cluster center and the number of cluster centers. The divided datasets are clustered by the DPC algorithm, and then the clustering results are perfected and integrated by using the cluster fusion rules. Finally, a variety of experiments are designed from various perspectives on various artificial simulated datasets and UCI real datasets, which demonstrate the superiority of the F-DPC algorithm in terms of clustering effect, clustering quality, and number of samples.

Causal Roles of Sleep Duration in Osteoporosis and Cardiometabolic Diseases: A Mendelian Randomization Study.

Sleep duration suggests some association with osteoporosis and cardiometabolic diseases, but it is unknown if these associations are causal or confounded. In this two-sample Mendelian randomization (MR) study, we included the largest genome-wide association studies (GWASs) associated with sleep duration and the outcome measures of osteoporosis and cardiometabolic diseases. Finally, 25 single nucleotide polymorphisms (SNPs) associated with short sleep duration and 7 SNPs associated with long sleep duration obtained the genome-wide significance (P < 5 × 10-8) and were used as instrumental variables. Genetic predisposition to short sleep duration was strongly associated with increased risk of coronary artery disease (beta-estimate: 0.199, 95% confidence interval CI: 0.081 to 0.317, standard error SE:0.060, P value = 0.001) and heart failure (beta-estimate: 0.145, 95% CI: 0.025 to 0.264, SE:0.061, P value = 0.017), which were both confirmed by the sensitivity analyses. Both short and long sleep duration may reduce the estimated bone mineral density (eBMD, beta-estimate: -0.086, 95% CI: -0.141 to -0.031, SE:0.028, P value = 0.002 for short sleep duration; beta-estimate: -0.080, 95% CI: -0.120 to -0.041, SE:0.020, P value < 0.0001 for long sleep duration). There was limited evidence of associations between sleep duration and fracture, type 2 diabetes, atrial fibrillation, fasting glucose, fasting insulin, or HbA1c. This study provides robust evidence that short sleep duration is causally associated with high risk of coronary artery disease and heart failure and suggests that short sleep duration should be avoided to prevent these two cardiovascular diseases. Short and long sleep duration show some MR association with reduced eBMD, which indicates that both short and long sleep duration may be prevented to reduce the incidence of osteoporosis.

Cryogen free spin polarized scanning tunneling microscopy and magnetic exchange force microscopy with extremely low noise.

Spin polarized scanning tunneling microscopy (SP-STM) and magnetic exchange force microscopy (MExFM) are powerful tools to characterize spin structure at the atomic scale. For low temperature measurements, liquid helium cooling is commonly used, which has the advantage of generating low noise but has the disadvantage of having difficulties in carrying out measurements with long durations at low temperatures and measurements with a wide temperature range. The situation is just reversed for cryogen-free STM, where the mechanical vibration of the refrigerator becomes a major challenge. In this work, we have successfully built a cryogen-free system with both SP-STM and MExFM capabilities, which can be operated under a 9 T magnetic field provided by a cryogen-free superconducting magnet and in a wide temperature range between 1.4 and 300 K. With the help of our specially designed vibration isolation system, the noise is reduced to an extremely low level of 0.7 pm. The Fe/Ir(111) magnetic skyrmion lattice is used to demonstrate the technical novelties of our cryogen-free system.

Tuning 2D magnetism in Fe3+XGeTe2 films by element doping.

Two-dimensional (2D) ferromagnetic materials have been discovered with tunable magnetism and orbital-driven nodal-line features. Controlling the 2D magnetism in exfoliated nanoflakes via electric/magnetic fields enables a boosted Curie temperature (T C) or phase transitions. One of the challenges, however, is the realization of high T C 2D magnets that are tunable, robust and suitable for large scale fabrication. Here, we report molecular-beam epitaxy growth of wafer-scale Fe3+XGeTe2 films with T C above room temperature. By controlling the Fe composition in Fe3+XGeTe2, a continuously modulated T C in a broad range of 185-320 K has been achieved. This widely tunable T C is attributed to the doped interlayer Fe that provides a 40% enhancement around the optimal composition X = 2. We further fabricated magnetic tunneling junction device arrays that exhibit clear tunneling signals. Our results show an effective and reliable approach, i.e. element doping, to producing robust and tunable ferromagnetism beyond room temperature in a large-scale 2D Fe3+XGeTe2 fashion.

Causal associations of circulating adiponectin with cardiometabolic diseases and osteoporotic fracture.

Circulating adiponectin shows some relationships with the occurrence of cardiometabolic diseases and osteoporotic fracture, but little is known about their causal associations. This two-sample Mendelian randomization (MR) study aims to explore the causal roles of circulating adiponectin in cardiometabolic diseases and osteoporotic fracture. We used 15 single nucleotide polymorphisms associated with circulating adiponectin as the instrumental variables. Inverse variance weighted, weighted median and MR-Egger regression methods were applied to study the causal associations. The results found that high circulating adiponectin was causally associated with reduced risk of type 2 diabetes (beta-estimate: -0.030, 95% CI: -0.048 to -0.011, SE: 0.009, P-value = 0.002) and may be the risk factor of coronary artery disease (beta-estimate: 0.012, 95% CI: 0.001 to 0.023, SE: 0.006, P-value = 0.030). No causal associations were seen between circulating adiponectin and other outcomes including heart failure, atrial fibrillation, cerebral ischemia, intracerebral hemorrhage or osteoporotic fracture. This study found the potential causal roles of high circulating adiponectin in reduced risk of type 2 diabetes and increased risk of coronary artery disease, which may help prevent and treat these two diseases.

Electrosynthesis of >20 g/L H2O2 from Air.

Hydrogen peroxide (HP) production via electrochemical oxygen reduction reaction (ORR-HP) is a critical reaction for energy storage and environmental remediation. The onsite production of high-concentration H2O2 using gas diffusion electrodes (GDEs) fed by air is especially attractive. However, many studies indicate that the air-GDE combination could not produce concentrated H2O2, as the [H2O2] leveled off or even decreased with the increasing reaction time. This study proves that the limiting factors are not the oxygen concentration in the air but the anodic and cathodic depletion of the as-formed H2O2. We proved that the anodic depletion could be excluded by adopting a divided electrolytic cell. Furthermore, we demonstrated that applying poly(tetrafluoroethylene) (PTFE) as an overcoating rather than a catalyst binder could effectively mitigate the cathodic decomposition pathways. Beyond that, we further developed a composite electrospun PTFE (E-PTFE)/carbon black (CB)/GDE electrode featuring the electrospun PTFE (E-PTFE) nanofibrous overcoating. The E-PTFE coating provides abundant triphase active sites and excludes the cathodic depletion reaction, enabling the production of >20 g/L H2O2 at a current efficiency of 86.6%. Finally, we demonstrated the efficacy of the ORR-HP device in lake water remediation. Cyanobacteria and microcystin-LR were readily removed along with the onsite production of H2O2.

Enhanced perfluorooctane acid mineralization by electrochemical oxidation using Ti3+ self-doping TiO2 nanotube arrays anode.

Perfluorooctanoic acid (PFOA) is of increasing concern due to its worldwide application and extremely environmental persistence. Herein, we demonstrated the electrochemical degradation of PFOA with high efficiency using the Ti3+ self-doping TiO2 nanotube arrays (Ti3+/TiO2-NTA) anode. The fabricated Ti3+/TiO2-NTA anode exhibited vertically aligned uniform nanotubes structure, and was demonstrated good performance on the electrochemical degradation of PFOA in water. The degradation rate, total organic carbon (TOC) removal rate and defluorination rate of PFOA reached 98.1 %, 93.3 % and 74.8 %, respectively, after electrolysis for 90 min at low current density of 2 mA cm-2. The energy consumption (7.6 Wh L-1) of this electrochemical oxidation system using Ti3+/TiO2-NTA anode for PFOA degradation was about 1 order of magnitude lower than using traditional PbO2 anodes. Cathodic polarization could effectively prolong the electrocatalytic activity of the anode by regenerating Ti3+ sites. PFOA molecular was underwent a rapidly mineralization to CO2 and F-, with only low concentration of short-chain perflfluorocarboxylic acids (PFCAs) intermediates identified. A possible electrochemical degradation mechanism of PFOA was proposed, in which the initial direct electron transfer (DET) on the anode to yield PFOA free radicals (C7F15COO•) and hydroxyl radicals (•OH) oxidation were greatly enhanced. This presented study provides a novel approach for the purification of the recalcitrant PFOA from wastewaters.

Photocatalytic hydrogen evolution by degradation of organic pollutants over quantum dots doped nitrogen carbide.

Semiconductor photocatalysts are of great importance for addressing current environmental and energy crises. In this study, we developed a simple exfoliation-sonication route to fabricate nitrogen carbide quantum dots (CNQDs) doped nitrogen carbide nanosheet (CNS) composite photocatalysts which were employed to produce hydrogen and degrade organic pollutants (methyl orange, acridine orange, aniline, and phenol) synchronously under visible light irradiation. The presence of acridine orange and aniline enhanced the hydrogen evolution efficiency from 8.8 mmol g-1 h-1 to 32.1 and 11.7 mmol g-1 h-1, respectively. On the contrary, methyl orange and phenol with the same concentration inhibited hydrogen evolution. Based on the proton chain and energy band analyses, the synchronous mechanism of photocatalytic hydrogen evolution and organic pollutant degradation on CNQDs/CNS was also proposed. On one side, the oxygen-containing functional groups on the surface of CNQDs and the surrounded water molecules constructed proton chains, increasing the combination probability between protons and photo-generated electrons. On the other side, the heterojunction of CNQDs/CNS induced the separation of photo-generated electron-hole pairs. The photo-generated electrons migrate to CNQDs, on which the protons were transformed into hydrogen molecules, while the holes migrated to CNS where the organic pollutants were oxidized synchronously.