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Abstract Copper (Cu)-based catalysts show promise for electrocatalytic CO2 reduction (CO2RR) to multi-carbon alcohols, but thermodynamic constraints lead to competitive hydrocarbon (e.g., ethylene) production. Achieving selective ethanol production with high Faradaic efficiency (FE) and current density is still challenging. Here we show a multivalent Cu-based catalyst, Cu-2,3,7,8-tetraaminophenazine-1,4,6,9-tetraone (Cu-TAPT) with Cu2+ and Cu+ atomic ratio of about 1:2 for CO2RR. Cu-TAPT exhibits an ethanol FE of 54.3 ± 3% at an industrial-scale current density of 429 mA cm−2, with the ethanol-to-ethylene ratio reaching 3.14:1. Experimental and theoretical calculations collectively unveil that the catalyst is stable during CO2RR, resulting from suitable coordination of the Cu2+ and Cu+ with the functional groups in TAPT. Additionally, mechanism studies show that the increased ethanol selectivity originates from synergy of multivalent Cu sites, which can promote asymmetric C–C coupling and adjust the adsorption strength of different carbonaceous intermediates, favoring hydroxy-containing C2 intermediate (*HCCHOH) formation and formation of ethanol.

The current-carrying arc is a critical factor that affects the electrical contact performance and material damage of contact pairs. In this study, a copper disk–copper disk pair was used to simulate the rolling electrical joint in a conductive rotating joint. Under operating conditions with a current of 2 A, rotation speeds from 4 to 600 r/min, and loads from 40 to 180 N, the dynamic behavior of the current-carrying arc and the surface damage mechanism were investigated. The movement characteristics of the arc at the friction interface were observed, and the arc generation difficulty and intensity were statistically analyzed based on the arc burning rate and arc energy. With increasing load and rotation speed, the generation of current-carrying tribological arcs became easier, and both the arc burning rate and arc energy increased. After the arc was generated, the arc root position was randomly distributed at the contact interface, exhibiting dynamic phenomena such as splitting and merging. Following the generation of the arc, the dominant damage mechanism at the current-carrying friction interface transitioned from mechanical damage to electrical damage. The manifestations of electrical damage included burning, oxidation, and roughening, with the degree of electrical damage positively correlated with the arc burning rate and arc energy. Surface oxidation could reduce the adhesion between metal contact pairs, contributing to a decrease in the current-carrying friction coefficient. Simultaneously, the film resistance caused by oxidation and the contraction resistance caused by roughening could lead to an increase in the average contact resistance.

Abstract Upcycling of CO2 into fuels by virtually unlimited solar energy provides an ultimate solution for addressing the substantial challenges of energy crisis and climate change. In this work, we report an efficient nanostructured Ru/MnOx catalyst composed of well-defined Ru/MnO/Mn3O4 for photo-thermal catalytic CO2 hydrogenation to CH4, which is the result of a combination of external heating and irradiation. Remarkably, under relatively mild conditions of 200 °C, a considerable CH4 production rate of 166.7 mmol g−1 h−1 was achieved with a superior selectivity of 99.5% at CO2 conversion of 66.8%. The correlative spectroscopic and theoretical investigations suggest that the yield of CH4 is enhanced by coordinating photon energy with thermal energy to reduce the activation energy of reaction and promote formation of key intermediate COOH* species over the catalyst. This work opens up a new strategy for CO2 hydrogenation toward CH4.

In order to clarify the content and structural changes of different pectin fractions in grape cell walls under ultrasonic treatment, the grapes were treated with different ultrasonic time and ultrasonic power in this study, and the content of pectin fractions, composition of monosaccharides and structural changes of grape cell walls were analyzed by means of carbazole sulfuric acid method, PMP pre-column derivatization, high-performance liquid gel chromatography , scanning electron microscopy, Fourier transform infrared spectroscopy and circular dichroism. Results showed that the highest and the lowest contents in fresh grape cell walls were alkali-soluble pectin (NSP) and chelate pectin (CSP), respectively, and they were 27.41 mg/g AIR and 8.25 mg/g AIR. The total pectin decreased after ultrasonic treatments, in which the water-soluble pectin (WSP) increased and the CSP and NSP decreased. A total of six monosaccharides were detected in three pectins, and the monosaccharides of different pectin were not the same. The galactose and arabinose were high in WSP, the glucuronic acid was the most abundant of CSP and the rhamnose were the highest in NSP. After ultrasonic treatment, the contents of monosaccharides decreased, while the composition did not change, and the main chain structure of pectin was no change, but the linear structure and the degree of branch chain were changed. With the increase of ultrasonic times and powers, the molecular weight of different pectins declined gradually. And in the microstructure showed a more loose morphology. In addition, ultrasonic treatment had an effect on the structure and chain conformation of CSP and NSP, which made their maximum response values shift, and the effect of ultrasonic power was more significant. In conclusion, ultrasonic treatment could reduce the pectin and monosaccharide contents in grape cell walls, and affect the molecular linear structure and molecular chain conformation of pectin. These results can provide theoretical basis for the quality change of grape products under ultrasonic treatment.

In order to promote self-sufficiency of strategic resources and comprehensive utilization of seawater chemical resources, this paper conducted research on the extraction and utilization of seawater chemical resources from the perspective of ensuring the security of strategic resources. This paper analyzed the current situation and the key directions of the extraction and utilization of seawater chemical resources in China, and put forward suggestions from four aspects including strengthening top-level design, improving institutional guarantee system, building cooperation mechanisms and strengthening technological innovation capacity, aiming to better ensure the security of China's strategic resources and alleviate the problem of foreign resources dependence. At the same time, it provided reference for the development and management of seawater chemical resources in China.

Furfuryl ethers have been considered to be a promising fuel additive. One step reduction etherification of furfural over supported Pd catalysts provides a facile way for the preparation of furfuryl ether. However, the preparation of a reusable Pd catalyst for reductive etherification remains to be a great challenge. In this study, a series of SiO2 supported Pd catalysts with particle size ranging from 2.2 nm to 28 nm were prepared. Their textural properties and catalytic performance in furfural reductive etherification have been systematically studied. The results herein shed light on the particle size effect on the competition between hydrogenation/hydrogenolysis of CO in furfural over Pd surface. We found out that Pd nanoparticles larger than 3 nm are preferred for one step reductive etherification. Based on this finding, we prepared a Pd/ZSM-5 bifunctional catalyst comprising Pd nanoparticles larger than 3 nm and decreased acidity in presence of amino organosilane, which served as a bifunctional catalyst succeeding in one-pot synthesis of ether via reductive-etherification and direct-etherification. This strategy showed significant advantage in efficiently converting furfuryl acohol, a major side-product, into ether, while suppressing the undesired side-reactions.

Abstract Anti-IL17A therapies have proven effective for numerous inflammatory diseases including psoriasis, axial spondylitis and psoriatic arthritis. Modulating and/or antagonizing protein–protein interactions of IL17A cytokine binding to its cell surface receptors with oral therapies offers the promise to bring forward biologics-like efficacy in a pill to patients. We used an NMR-based fragment screen of recombinant IL17A to uncover starting points for small molecule IL17A antagonist discovery. By examining chemical shift perturbations in 2D [1H, 13C-HSQC] spectra of isotopically labeled IL17A, we discovered fragments binding the cytokine at a previously undescribed site near the IL17A C-terminal region, albeit with weak affinity (> 250 µM). Importantly this binding location was distinct from previously known chemical matter modulating cytokine responses. Subsequently through analog screening, we identified related compounds that bound symmetrically in this novel site with two copies. From this observation we employed a linking strategy via structure-based drug design and obtained compounds with increased binding affinity (

Abstract Background The staging of nasopharyngeal carcinoma (NPC) is of great value in treatment and prognosis. We explored whether a positron emission tomography/ magnetic resonance imaging (PET/MRI) based comprehensive model of radiomics features and semiquantitative parameters was useful for clinical evaluation of NPC staging. Materials and methods A total of 100 NPC patients diagnosed with non-keratinized undifferentiated carcinoma were divided into early-stage group (I—II) and advanced-stage group (III—IV) and divided into the training set (n = 70) and the testing set (n = 30). Radiomics features (n = 396 × 2) of the primary site of NPC were extracted from MRI and PET images, respectively. Three major semiquantitative parameters of primary sites including maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) in all NPC patients were measured. After feature selection, three diagnostic models including the radiomics model, the metabolic parameter model, and the combined model were established using logistic regression model. Finally, internal validation was performed, and a nomogram for NPC comprehensive diagnosis has been made. Results The radiomics model and metabolic parameter model showed an area under the curve (AUC) of 0.83 and 0.80 in the testing set, respectively. The combined model based on radiomics and semiquantitative parameters showed an AUC of 0.90 in the testing set, with the best performance among the three models. Conclusion The combined model based on PET/MRI radiomics and semiquantitative parameters is of great value in the evaluation of clinical stage (early-stage group and advanced-stage group) of NPC.

Chrysanthemum White Rust (CWR) caused by Puccinia horiana Henn. is a major disease in the production process of chrysanthemum, which is widely spread all over the world and can be called “cancer” of chrysanthemum. To clarify the disease resistance function of disease resistance genes can provide a theoretical basis for the utilization and genetic improvement of chrysanthemum resistant varieties. In this study, the resistant cultivar ‘China Red’ was used as the experimental material. We constructed the silencing vector pTRV2-CmWRKY15-1 and obtained the silenced line named TRV-CmWRKY15-1. The results of enzyme activity after inoculation with pathogenic fungi showed that the activities of antioxidant enzymes SOD, POD, CAT and defense-related enzymes PAL and CHI in leaves were stimulated under the stress of P. horiana. In the WT, the activities of SOD, POD and CAT at the peak value were 1.99 times, 2.84 times and 1.39 times higher than that in TRV-CmWRKY15-1, respectively. And the activities of PALand CHI at the peak were 1.63 times and 1.12 times of TRV-CmWRKY15-1. The content of MDA and soluble sugar also confirmed that chrysanthemum was more susceptible to pathogenic fungi when CmWRKY15-1 was silenced. The expression levels of POD, SOD, PAL and CHI at different time points showed that the expressions of defense enzyme related genes were inhibited in TRV-WRKY15-1 under the infection of P. horiana, which weakened the ability of chrysanthemum to resist white rust. In conclusion, CmWRKY15-1 may increased the resistance of chrysanthemum to white rust by increasing the activity of protective enzyme system, which laid a foundation for breeding new varieties with disease resistance.

Abstract A core–shell structured Mg(OH)2/PS with enhanced surface lipophilicity was successfully synthesized by a microemulsion template. The core magnesium hydroxide was prepared in a cetyltrimethyl ammonium bromide (CTAB)/isopropanol/cyclohexane/water microemulsion, and the shell polystyrene (PS) was formed in situ by adding styrene monomer into oil phase of the microemulsion. The Mg(OH)2/PS core–shell nanoparticles were characterized by X‐ray diffraction (XRD), scanning electron microscopy (SEM), X‐ray photoelectron spectroscopy (XPS), thermogravimetry/differential scanning calorimetry (TG/DSC) and Fourier transform infrared spectroscopy (FT‐IR). The results indicated that the obtained nanoparticles is a core–shell structure and well‐dispersed; the polystyrene shell thicknesses could be controlled in the range of 9.11 to 13.36 nm by simply changing the dosage of styrene monomer. Due to its polymer coating modification and integrated core–shell structure, the Mg(OH)2/PS is with excellent surface lipophilicity and easy to mix with the organic phase. The results provide a facile method to produce the surface‐modified inorganic material for functionality.

Aims: To evaluate the efficacy of medical thoracoscopy-assisted argon plasma coagulation in association with autologous blood pleurodesis in spontaneous pneumothorax. Patients and methods: Three male patients with spontaneous pneumothorax were treated; medical thoracoscopy-assisted argon plasma coagulation combined with autologous blood pleurodesis was conducted for all patients whose duration of the air leak exceeded 7 days. We systematically reviewed all of the relevant literature to analyze and sum up the treatments of secondary spontaneous pneumothorax. Results: The air leaks were all sealed and no recurrence of pneumothorax was reported. No complications of fever, bleeding, or signs of infection were observed during the process. Conclusion: The authors believe that the combination of medical thoracoscopy-assisted argon plasma coagulation and autologous blood pleurodesis is safe and effective. However, due to the number of patients included in this uncontrolled case study, more cases will be collected in the future. The reviews of this paper are available via the supplemental material section.

Electrocatalytic nitrate reduction reaction (NO3RR) coupled with organic compounds to synthesize oximes for value-added conversion of waste pollutants has very promising prospects. However, due to the susceptibility of the feedstock to hydrogenation, the relatively low reaction efficiency, and the poor stability of oximes, the reaction in acidic electrolytes remains a formidable challenge. Herein, we report a novel strategy for the one-step synthesis of oximes from nitrite and aldehydes/ketones in acidic electrolytes using a Zn-based catalyst (multilayered Zn nanosheet catalyst, M-ZnNSs). 99% yield and 99% selectivity of phenylacetaldehyde oxime were achieved at a constant current of -12 mA cm-2. Moreover, various aldehydes/ketones were efficiently converted to oximes with yield and selectivity up to >90%, demonstrating the high versatility of this method. Furthermore, the catalyst exhibited remarkable long-term stability (>100 h). This work proposes a green strategy to promote the recycling of nitrogen resources, enhance the value of NO3- conversion products, and develop new ideas for electrochemical C-N coupling. [ABSTRACT FROM AUTHOR]

How to endow carbon fiber (CF) with functions such as good energy storage while maintaining its excellent mechanical properties is an interesting research topic. A novel flexible and bendable CF battery (FBCFB) with spread ultra-thin CF unidirectional tape is prepared in this article for the first time, which consists of a CF nickel-plated positive electrode (PE), a copper foil negative electrode (NE), a separator, and a liquid electrolyte. The electrochemical performances of the battery are tested at different bending angles. Further, a structural battery tube (SBT) made of ultra-thin CF prepreg skin and FBCFB is formed by winding process. The storage energy and the loading effects of SBT are tested under three-point bending conditions. The full CF tube (FCFT) with the same geometric dimensions is tested to find the structural efficiency of the SBT. The results show that the specific storage energy capacity of FBCFB reaches 184 mAh at a charge-discharge rate of 0.05 A, and its electrochemical performance presents stable in the range of 0 ~ 135°. The energy density of SBT reaches 26 Wh/kg, and its maximum bending load ratio is 81 N/g, which is 67% of the pure CF composite tube. The residual energy capacity of SBT after bending failure is 60% of its initial capacity. The experimental results show the comprehensive advantages of the structural loading-energy storage synergy of ultra-thin CF structure battery tubes. [ABSTRACT FROM AUTHOR]