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Proton-exchange membrane fuel cells (PEMFCs) and water electrolysis (PEMWE) are rapidly developing hydrogen energy conversion devices. Catalyst layers and membranes have been studied extensively and reviewed. However, few studies have compared gas diffusion layers (GDLs) in PEMWE and PEMFC. This review compares the differences and similarities between the GDLs of PEMWE and PEMFC in terms of their material and mass transport characteristics. First, the GDL materials are selected based on their working conditions. Carbon materials are prone to rapid corrosion because of the high anode potential of PEMWEs. Consequently, metal materials have emerged as the primary choice for GDLs. Second, the mutual counter-reactions of the two devices result in differences in mass transport limitations. In particular, water flooding and the effects of bubbles are major drawbacks of PEMFCs and PEMWE, respectively; well-designed structures can solve these problems. Imaging techniques and simulations can provide a better understanding of the effects of materials and structures on mass transfer. Finally, it is anticipated that this review will assist research on GDLs of PEMWE and PEMFC.
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Proton exchange membranes (PEMs) are subject to mechanical degradation, such as microcracks and pinhole formation, under real-world fuel cell operating conditions, which leads to great issues in terms of device death and safety concerns. Therefore, PEMs with self-healing features are imperative but have rarely been used for proton exchange membrane fuel cells (PEMFCs). Here, a dimensionally stable and self-healing PEM is developed by tuning the hydrogen bond and dipole-dipole interactions between the mature perfluorinated sulfonic acid (PFSA) and a self-healing copolymer, which is specifically synthesized with hexafluorobutyl acrylate (HFBA) and acrylic acid (AA). This hexafluorobutyl acrylate-acrylic acid copolymer (HFBA-co-AA) is suggested as the key to improving the self-healing efficiency of the blended PFSA/HFBA-co-AA membrane. This PFSA/HFBA-co-AA membrane can recover 43.6% of the original tensile strength within only 20 min at 80 °C. This study may pave an avenue toward the development of reliable and durable PEM for fuel cells.
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Herein, a straightforward protocol was developed for the one-pot synthesis of N-doped lignosulfonate-derived carbons (NLDCs) with a tunable porous structure using natural amino acids-templated self-assembly strategy. Specifically, histidine was employed as a template reagent, leading to the preparation of 10-NLDC-21 with remarkable characteristics, including the large specific surface area (SBET = 1844.5 m2/g), pore volume (Vmes = 1.22 cm3/g) and efficient adsorption for atrazine (ATZ) removal. The adsorption behavior of ATZ by NLDCs followed the Langmuir and pseudo-second-order models, suggesting a monolayer chemisorption nature of ATZ adsorption with the maximum adsorption capacity reached up to 265.77 mg/g. Furthermore, NLDCs exhibited excellent environmental adaptability and recycling performance. The robust affinity could be attributed to multi-interactions including pore filling, electrostatic attraction, hydrogen bonding and π-π stacking between the adsorbents and ATZ molecules. This approach offers a practical method for exploring innovative bio-carbon materials for sewage treatment.
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Atrazina , Carbono , Lignina , Poluentes Químicos da Água , Atrazina/química , Lignina/química , Lignina/análogos & derivados , Porosidade , Adsorção , Carbono/química , Concentração de Íons de Hidrogênio , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , CinéticaRESUMO
Iodine is one of the most effective sources for iodination of aromatic compounds; however, its electrophilicity is insufficient for direct iodination. The selection of appropriate environmentally friendly and cost-effective oxidants in combination with iodine for the iodination of aromatic rings, along with its application in the synthesis of natural products, holds significant importance. A highly efficient method utilizing I(III) as the initiator has been successfully developed for monoiodination of arylaldehydes. The method demonstrates good compatibility with a wide range of (hetero)aromatic aldehydes, resulting in moderate to excellent yields, without the need for any toxic, volatile or explosive reagents. The synthesis of seven natural products, namely aristogins A-F and hernandial, was achieved through this iodination followed by Ullmann-type coupling.
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Piezo-synthesis of H2O2 utilizing sustainable mechanical energy as well as earth-abundant water and oxygen is a green, cost-effective, and promising approach. However, achieving simultaneous two-electron water oxidation reaction (2e- WOR) and two-electron oxygen reduction reaction (2e- ORR) faces huge challenges due to insufficient synergistic active sites and slow/messy carrier transfer. Herein, a novel 2D/2D van der Waals heterojunction consisting of BiOIO3 and carbon nitride (BIO/CN) is elaborately designed for highly efficient overall H2O2 piezo-synthesis. Theoretical/experimental results reveal that a Z-scheme electron transfer is formed and facilitated by the tandem interfacial electric field and the bulk piezo-polarization field. On this basis, the carriers are efficiently separated while the oxidation/reduction capacity is preserved, thus providing the strong driving force for the 2e- WOR and 2e- ORR on BIO and CN, respectively. Furthermore, the kinetic and thermodynamic processes of WOR and ORR for H2O2 synthesis improve remarkably. Therefore, BIO/CN exhibits an excellent H2O2 yield of 259.8 µM within 30 min in pure water and air atmosphere (without any sacrificial agents and aeration). This study provides a new idea on strategically controlling electron transfer toward high-efficiency H2O2 piezo-synthesis and expands the avenue for developing effective environmental purification materials.
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The cathodic oxygen reduction reaction (ORR) has been continuously attracting worldwide interest due to the increasing popularity of proton exchange membrane (PEM) fuel cells. So far, various Pt-group metal (PGM) or PGM-free catalysts have been developed to facilitate the ORR. However, there is still a gap to achieve the expected goals as proposed by the U.S. Department of Energy (DoE). Recently, PGM-free@PGM hybrid catalysts, such as the M/N/C@PtM catalyst, have achieved the milestones of oxygen reduction, as reviewed in our recent work. It is, nevertheless, still challenging to unravel the underlying structure-property relationships. Here, by applying different Pt/Co ratios, a series of Co/N/C@PtxCo catalysts are synthesized. Interestingly, the ORR activity and stability are not linear with the Pt content, but show a volcano-like curve with increased Pt usage. This relationship has been deeply unraveled to be closely related to the contents of pyrrolic N, pyridinic N, and graphitized carbon in catalysts. This work provides guidelines to rationally design the coupled PGM-free@PGM catalysts toward the ORR by appropriate surface engineering.
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BACKGROUND: To evaluate the efficacy, effectiveness and safety of fermented Ophiocordyceps sinensis mycelium (FOSM) products for preventing contrast-associated acute kidney injury (CA-AKI). METHODS: Randomized controlled trials were searched from four Chinese and four English electronic databases and three clinical trial registries up to July 2023. Methodological quality was assessed by using the Cochrane risk-of-bias tool 2.0. Risk difference (RD) or risk ratio (RR) and mean difference (MD) were calculated along with the 95% confidence intervals (CIs). RESULTS: Fourteen trials testing three types of FOSM products (Bailing, Zhiling, and Jinshuibao capsules) involving 1271 participants injected contrast agents were included. For the risk of bias, all trials were rated as some concerns. Compared with routine preventive procedure (RPP) (saline hydration and alprostadil), FOSM products plus RPP showed beneficial effects in reducing the incidence of CA-AKI (14.62% and 5.35%, respectively; RD -0.06, 95% CI -0.09 to -0.03). Subgroup analysis showed that Bailing/Jinshuibao plus RPP demonstrated lower incidence of CA-AKI compared to RPP. However, there was no statistically significant difference between Zhiling with RPP and RPP in the incidence of CA-AKI. Additionally, only when FOSM products were taken before injection of the contrast, it was superior to RPP in reducing the incidence of CA-AKI. There was no statistical difference in adverse events between these two groups. CONCLUSIONS: Low certainty evidence suggests that preventive oral use of FOSM products as an adjuvant agent was safe and might decrease the incidence of CA-AKI. However, high-quality placebo-controlled trials are needed to confirm its benefit.
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Injúria Renal Aguda , Produtos Biológicos , Cordyceps , Humanos , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/epidemiologia , Injúria Renal Aguda/prevenção & controle , Adjuvantes Farmacêuticos , Ensaios Clínicos Controlados Aleatórios como Assunto , Produtos Biológicos/uso terapêuticoRESUMO
This study describes a catalyst-free α-acyloxylation of ketones and a KBr-mediated α-acyloxylation of cyclic ethers. These conversions are effectively mediated by hypervalent iodine(III) reagents serving dual roles as the oxidant and nucleophilic source. Consequently, esters are produced directly in moderate to excellent yields. The proposed method features good functional group compatibility, a broad substrate scope, and high synthetic efficiency and is remarkably environmentally friendly.
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Piezo-self-Fenton system (PESF) has been emerging as a promising water treatment technology but suffering from unsatisfied H2 O2 production efficiency. Herein, we rationally design a Bi12 O17 Cl2 piezo-catalyst with multiple [Bi-O]n interlayers towards highly efficient H2 O2 production. The introduction of [Bi3 O4.25 ] layers initiates dual two-electron pathway for H2 O2 generation by altering the interlayer properties. It is found that the additional [Bi3 O4.25 ] layers not only enhance the polarization electric field but also serve as active sites for triggering dual pathways of two-electron O2 reduction and H2 O oxidation reaction for H2 O2 production. Therefore, the Bi12 O17 Cl2 exhibits an ultrahigh rate of H2 O2 generation (7.76â mM h-1 g-1 ) in pure water. Based on the adequate H2 O2 yield, a PESF was constructed for acetaminophen (ACE) degradation with an apparent rate constant of 0.023â min-1 . This work not only presents a potential strategy of tuning the activity of bismuth based piezo-catalysts but also provides a good example on the construction of highly efficient PESF for environmental remediation by using natural mechanical energy.
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ABSTRACTThe affect-as-information (AAI) model proposes that emotions influence the accessibility and value of information (Avramova & Inbar, 2013). Furthermore, according to the dual-process model of moral judgement, emotions and cognition influence moral judgement (Greene, 2007; Greene et al., 2001, 2008); however, there is no direct evidence of a causal chain to support this model's proposition. By using a 3 (emotions: positive vs. neutral vs. negative) × 2 (primed rule: save lives vs. do not kill) between-participants design, we examined two hypotheses in two experiments: supraliminal (Experiment 1) and subliminal (Experiment 2) priming. Our results partially supported the AAI model and confirmed that emotions and cognition independently influence moral judgement. Specifically, the positive emotions group made more utilitarian decisions after being primed with the "save lives" rule and more deontological decisions after being primed with the do not kill rule. However, priming did not affect moral judgement in the negative emotion condition. Further, irrespective of whether priming was done, the negative emotion group mostly made utilitarian decisions. Accordingly, we propose a dynamic dual-process model of moral judgement, that can help clarify how emotion and cognition influence moral judgement.
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Cognição , Julgamento , Humanos , Emoções , Princípios MoraisRESUMO
Piezo-catalytic self-Fenton (PSF) system has been emerging as a promising technique for wastewater treatment, while the competing O2 reductive hydrogen peroxide (H2 O2 ) production and FeIII reduction seriously limited the reaction kinetics. Here, we develop a two-electron water oxidative H2 O2 production (WOR-H2 O2 ) coupled with FeIII reduction over a FeIII /BiOIO3 piezo-catalyst for highly efficient PSF. It is found that the presence of FeIII can simultaneously initiate the WOR-H2 O2 and reduction of FeIII to FeII , thereby enabling a rapid reaction kinetics towards subsequent Fenton reaction of H2 O2 /FeII . The FeIII initiating PSF system offers exceptional self-recyclable degradation of pollutants with a degradation rate constant for sulfamethoxazole (SMZ) over 3.5 times as that of the classic FeII -PSF system. This study offers a new perspective for constructing efficient PSF systems and shatters the preconceived notion of FeIII in the Fenton reaction.
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Third-party punishment (TPP) effectively promotes social cooperation and maintains social norms in which equity plays a decisive role. When third-party and players are affiliated with different groups, there are two distinct phenomena-in-group favoritism (IGF) and black sheep effect (BSE)-in a certain environment. Equity loses its function as a benchmark when the environment is uncertain (de Kwaadsteniet et al., 2013). Thus, we hypothesized that individuals have a stronger IGF because there is more room for interpretations of their behaviors when an uncertain environment results in ambiguous social norms. We utilized a common resource dilemma (CRD) to manipulate the environmental uncertainty by varying the range of the resource size: a certain environment is represented by a resource size of fixed tokens (i.e., 500 tokens) and an uncertain one is represented by that of 300 to 700 tokens. Additionally, group affiliation is manipulated by the alumni relation between the third-party and players. The present study revealed that the uncertain environment led to stricter costly punishment. The experiment confirms the IGF rather than the BSE. We found boundary conditions between IGF and out-group derogation (OGD). When the players' harvest was not obviously violated, the size of TPP for a control group without group affiliation manipulation anchored those of the in-group and OGD occurred. Opposite, when the harvest was obviously violated, the size of TPP for the control group anchored those of the out-group and IGF occurred. The gender of the third-party affects its decision to punish, with men anchoring the control group's punishment to the in-group and showing OGD, whereas women anchoring the control group's punishment to the out-group and showing IGF.
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Comportamento Cooperativo , Punição , Humanos , Feminino , Incerteza , Comportamento Social , Normas SociaisRESUMO
In recent years, researchers have placed great importance on the use of silicon (Si)-related materials as efficient light sources for the purpose of realizing Si-based monolithic optoelectronic integration. Previous works were mostly focused on Si nanostructured materials, and, so far, exciting results from Si-based compounds are still lacking. In this paper, we have systematically demonstrated the high photoluminescence external quantum efficiency (PL EQE) and internal quantum efficiency (PL IQE) of amorphous silicon oxynitride (a-SiNxOy) systems. Within an integration sphere, we directly measured the PL EQE values of a-SiNxOy, which ranged from approximately 2% to 10% in the visible range at room temperature. Then, we calculated the related PL IQE through temperature-dependent PL measurements. The obtained PL IQE values (~84% at 480 nm emission peak wavelength) were very high compared with those of reported Si-based luminescent thin films. We also calculated the temperature-dependent PL EQE values of a-SiNxOy systems, and discussed the related PL mechanisms.
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Currently, the development of high-performance protonic ceramic cells (PCCs) is limited by the scarcity of efficient mixed protonic-electronic conducting oxides that can act as air electrodes to satisfy the high protonic conductivity of electrolytes. Despite the extensive research efforts in the past decades, the development of mixed protonic-electronic conducting oxides still remains in a trial-and-error process, which is extremely time consuming and high cost. Herein, based on the data acquired from the published literature, the machine-learning (ML) method is introduced to accelerate the discovery of efficient mixed protonic-electronic conducting oxides. Accordingly, the hydrated proton concentration (HPC) of 3200 oxides is predicted to evaluate the proton conduction that is essential for enhancing the electrochemical performances of PCCs. Subsequently, feature importance for HPC is evaluated to establish a guideline for rapid and accurate design and development of high-efficiency mixed protonic-electronic conducting oxides. Thereafter, screened (La0.7 Ca0.3 )(Co0.8 Ni0.2 )O3 (LCCN7382) is prepared, and the experimental HPC adequately corresponds with the predicted results. Moreover, the PCC with LCCN7382 exhibits satisfactory electrochemical performances in electrolysis and fuel cell modes. In addition to the development of a promising air electrode for PCC, this study establishes a new avenue for ML-based development of mixed protonic-electronic conducting oxides.
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Developing FeOOH as a robust electrocatalyst for high output oxygen evolution reaction (OER) remains challenging due to its low conductivity and dissolvability in alkaline conditions. Herein, it is demonstrated that the robust and high output Zn doped NiOOH-FeOOH (Zn-Fex Ni(1-x) )OOH catalyst can be derived by electro-oxidation-induced reconstruction from the pre-electrocatalyst of Zn modified Ni metal/FeOOH film supported by nickel foam (NF). In situ Raman and ex situ characterizations elucidate that the pre-electrocatalyst undergoes dynamic reconstruction occurring on both the catalyst surface and underneath metal support during the OER process. That involves the Fe dissolution-redeposition and the merge of Zn doped FeOOH with in situ generated NiOOH from NF support and NiZn alloy nanoparticles. Benefiting from the Zn doping and the covalence interaction of FeOOH-NiOOH, the reconstructed electrode shows superior corrosion resistance, and enhanced catalytic activity as well as bonding force at the catalyst-support interface. Together with the feature of superaerophobic surface, the reconstructed electrode only requires an overpotential of 330 mV at a high-current-density of 1000 mA cm-2 and maintains 97% of its initial activity after 1000 h. This work provides an in-depth understanding of electrocatalyst reconstruction during the OER process, which facilitates the design of high-performance OER catalysts.
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The morphology, microstructure as well as the orientation of cathodic materials are the key issues when preparing high-performance aqueous zinc-ion batteries (ZIBs). In this paper, binder-free electrode Mn(OH)2 nanowire arrays were facilely synthesized via electrodeposition. The nanowires were aligned vertically on a carbon cloth. The as-prepared Mn(OH)2 nanowire arrays were used as cathode to fabricate rechargeable ZIBs. The vertically aligned configuration is beneficial to electron transport and the free space between the nanowires can provide more ion-diffusion pathways. As a result, Mn(OH)2 nanowire arrays yield a high specific capacitance of 146.3 Ma h g-1 at a current density of 0.5 A g-1. They also demonstrates ultra-high diffusion coefficients of 4.5 × 10-8~1.0 × 10-9 cm2 s-1 during charging and 1.0 × 10-9~2.7 × 10-11 cm-2 s-1 during discharging processes, which are one or two orders of magnitude higher than what is reported in the studies. Furthermore, the rechargeable Zn//Mn(OH)2 battery presents a good capacity retention of 61.1% of the initial value after 400 cycles. This study opens a new avenue to boost the electrochemical kinetics for high-performance aqueous ZIBs.
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Background: Hemoptysis is a common clinical symptom. In the chronic tuberculosis cavity and chronic necrotizing pneumonia cavity, pseudoaneurysms (Pas) easily form and are prone to massive hemoptysis and repeated hemoptysis and can even endanger patient's life. However, it remains to be further analyzed whether Pas of the pulmonary chronic inflammatory cavity selectively affect the peripheral pulmonary branches. This study is based on selective angiography to classify peripheral pulmonary arterial Pas (PAPs) of the pulmonary chronic inflammatory cavity and to determine treatment options for PAPs, thereby guiding individualized clinical treatment. Methods: Angiographic data of 392 noncancer patients undergoing hemoptysis were retrospectively analyzed. All of the patients underwent pulmonary and selective pulmonary angiography and bronchial and nonbronchial systemic collateral arterial angiography. A total of 9 patients had Pas of the pulmonary chronic inflammatory cavity, and a pseudoaneurysm systemic artery collateral (Pasac), inflow and outflow sections of the parent vessels, and direction of blood flow in the parent vessels were clearly observed with digital subtraction angiography (DSA) and/or C-arm cone-beam flat-panel detector computed tomography angiography (CBCTA). Patients with underlying disease had pulmonary tuberculosis (n=8) or lung abscess (n=1). The angiographic types of Pas were analyzed. Results: Eight patients with chronic pulmonary tuberculosis and 1 patient with a necrotizing pneumonia cavity in the convalescent period were included in the study. Pas of the pulmonary chronic inflammatory cavity presented the following types: (I) pulmonary artery pseudoaneurysm (PAPa) (n=2 cases); (II) body arterial Pa (n=3 cases); and (III) systemic-pulmonary anastomosis Pa. Each type could be divided into two subtypes (n=4 cases). In nine cases, embolization and hemostasis were technically and clinically successful. Conclusions: Pas of the pulmonary chronic inflammatory cavity are diverse (especially in cases of pulmonary tuberculosis). Angiographic typing plays a guiding role in the selection of an embolization strategy.
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Developing efficient electrocatalysts for nitrate reduction in wastewater is of great urgency now. High electrocatalytic activity of Zn@BN toward the electrocatalytic NO3RR to NH3 has been identified by density functional calculations, for which the most energy favourable pathway is energy downhill. The electron localization function is significantly correlated with the hydrogenation selectivity of the *NO intermediate.
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Nitratos , Óxidos de Nitrogênio , Hidrogenação , Águas Residuárias , ZincoRESUMO
Lithium-ion batteries (LIBs) are considered the promising next-generation advanced energy storage devices. It is very important to quickly screen out ideal anode materials for LIBs with excellent performance. In this work, an effective procedure is designed for the high-throughput screening of the three kinds of LIB anode materials from 131 613 inorganic compounds in the Materials Project database. The high throughput screen procedure was not only reliable but was also easily realized. Three ideal anode materials were obtained by considering remarkable thermodynamic stability, Li capacity larger than 372 mA h g-1, band gap smaller than 1.0 eV, and two-dimensional constraint. Furthermore, open-circuit voltage, volume expansion ratio, and the diffusion energy barrier were calculated by the DFT-D corrected density functional method. We believe that our high throughput screen procedure can effectively and accurately search for other kinds of anode materials, which can strongly support the theoretical basis for experimental research.
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Aqueous multivalent ion batteries, especially aqueous zinc-ion batteries (ZIBs), have promising energy storage application due to their unique merits of safety, high ionic conductivity, and high gravimetric energy density. To improve their electrochemical performance, polyaniline (PANI) is often chosen to suppress cathode dissolution. Herein, this work focuses on the zinc ion storage behavior of a PANI cathode. The energy storage mechanism of PANI is associated with four types of protonated/non-protonated amine or imine. The PANI cathode achieves a high capacity of 74 mAh g-1 at 0.3 A g-1 and maintains 48.4% of its initial discharge capacity after 1000 cycles. It also demonstrates an ultrahigh diffusion coefficient of 6.25 × 10-9~7.82 × 10-8 cm-2 s-1 during discharging and 7.69 × 10-10~1.81 × 10-7 cm-2 s-1 during charging processes, which is one or two orders of magnitude higher than other reported studies. This work sheds a light on developing PANI-composited cathodes in rechargeable aqueous ZIBs energy storage devices.