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The effect of stormwater runoff on dissolved organic matter (DOM) in rivers is one of the central topics in water environment research. Jiujiang is one of the first cities established in the Green Development Demonstration Zone of the Yangtze River Economic Belt (Jiangxi Province, China). Three-dimensional excitation–emission matrix fluorescence with parallel factor analysis (3DEEM-PARAFAC) and ultraviolet–visible (UV-Vis) spectroscopy were used to explore the effects of runoff on organic matter in Shili River (Jiujiang, Jiangxi Province, China). The results show that the runoff led to an increase of some critical pollutants and DOM concentrations, especially in the middle reaches of the river. The concentration and relative molecular weight of DOM in water increased as a result of runoff. Three humic-like (C1–C3) and two protein-like (C4 and C5) components of DOM were identified using the PARAFAC model. The sources of the three humic-like components were consistent, unlike those of the protein-like component C4. The runoff contained lower amounts of humic compounds which caused the relative content and proportion of humic substances little change and protein-like species increasing. The DOM mainly derived from autochthonous sources, and runoff had limited effect on its characteristics. The PARAFAC components could adequately represent different indicators and sources of DOM in urban rivers, providing an important reference for urban river management.

Unique structure and performance in prominent high-entropy ceramics (HECs) have attracted enormous attentions recently. In this work, we have successfully synthesized pure-phase (Bi1/6Na1/6Sr1/6Ba1/6Pb1/6Ca1/6)TiO3 (BNSBPC) and (Bi1/6La1/6Na1/6K1/6Sr1/6Ba1/6)TiO3 (BLNKSB) HECs by conventional solid-state method. Rietveld refinement results show that BNSBPC composition possesses tetragonal phase (P4mm) while the BLNKSB one exhibits cubic phase (Pm $$\overline{3}$$ m). Dielectric characterization reveals distinct relaxation behaviors between BNSBPC and BLNKSB compositions. Relaxor-like nature in BNSBPC and Debye medium in BLNKSB one are verified by dielectric, ferroelectric and Raman spectra characterizations. Maximal electrocaloric effect (ECE, ΔTmax) reaches 0.63 K with relatively narrow temperature span (ΔTspan) of ~ 20 K at 60 kV cm−1 for BNSBPC ceramic, while the BLNKSB one possesses superior temperature stability (ΔTspan = 100 K) with ΔTmax = 0.14 K. Room-temperature ECE is also obtained by home-made adiabatic calorimeter, which indicates a positive ECE for both compositions. Finally, phase structure, dielectric properties and ECE in two high-entropy compositions are comparatively discussed to explore structure–ECE relationships in HECs. The superior thermal stability of ECE in BLNKSB samples provides a broad prospect for designing solid-state refrigeration.

Background Despite evidence that high-flow nasal cannula oxygen therapy (HFNC) promotes oxygenation, its application in sedated gastroscopy in elderly patients has received little attention. This study investigated the effect of different inhaled oxygen concentrations (FiO2) of HFNC during sedated gastroscopy in elderly patients. Methods In a prospective randomized single-blinded study, 369 outpatients undergoing regular gastroscopy with propofol sedation delivered by an anesthesiologist were randomly divided into three groups (n = 123): nasal cannula oxygen group (Group C), 100% FiO2 of HFNC group (Group H100), and 50% FiO2 of HFNC (Group H50). The primary endpoint in this study was the incidence of hypoxia events with pulse oxygen saturation (SpO2) ≤ 92%. The secondary endpoints included the incidence of other varying degrees of hypoxia and adverse events associated with ventilation and hypoxia. Results The incidence of hypoxia, paradoxical response, choking, jaw lift, and mask ventilation was lower in both Group H100 and Group H50 than in Group C (P P > 0.05). No patients were mechanically ventilated with endotracheal intubation or found to have complications from HFNC. Conclusion HFNC prevented hypoxia during gastroscopy with propofol in elderly patients, and there was no significant difference in the incidence of hypoxia when FiO2 was 50% or 100%. Trial registration This single-blind, prospective, randomized controlled trial was approved by the Ethics Committee of Nanjing First Hospital (KY20201102-04) and registered in the China Clinical Trial Center (20/10/2021, ChiCTR2100052144) before patients enrollment. All patients signed an informed consent form.

In this work, we demonstrate that pure three-dimensional honeycomb-like porous carbons (3D-HPC) can be prepared by one-step simultaneous carbonization and activation of Ganoderma lucidum spores (GLS) with KOH active agent. Benefiting from the specific natural morphology of GLS and uniform activation process, the obtained 3D-HPC exhibits pure honeycomb-like hierarchical structures. The obtained 3D-HPC-900 shows the honeycomb-like structures and a high density of narrow mesopores, leading to a high accessible surface area. Combined with high specific surface area of 1995 m2 g−1 and oxygen/nitrogen doping, 3D-HPC-900 exhibits a high specific capacitance of 224 F g−1 at a current density of 0.25 A g−1, an ultrahigh capacitance retention of 75.9% even the current density increased by 80 times, and an excellent cycling stability with 100% capacitance retention after 50,000 cycles. More importantly, the maximum energy density can reach up to 75.7 W h kg−1 at the power density of 1750 W kg−1 in ionic liquid. Meanwhile, the experimental results clearly reveal the exclusive effects of mesopores on improving the rate performance in electrochemical capacitors. Therefore, the work provides a clear method on preparation of high-valued honeycomb-like structured carbon materials to enhance the rate capability of carbon-based electrochemical capacitors.

Despite the widespread use of anilines, synthetic challenges to these targets still exist. Selectivity is often an issue, when using the traditional nitration-reduction sequence or more modern approaches, including arene C–H aminations catalyzed by transition metals, photosensitizers, or electrodes. Accordingly, there is still a need for general methods to rapidly, directly access specific isomers of substituted anilines. Here, we report a simple route towards the synthesis of such motifs starting from benzyl alcohols, which are converted to anilines by the use of arylsulfonyl hydroxylamines, via an aza-Hock rearrangement. Good to excellent yields are observed. The method is applicable to various benzyl alcohol surrogates (such as ethers, esters, and halides) as well as simple alkylarenes. Functionalizations of pharmaceutically relevant structures are feasible under the reaction conditions. Over ten amination reagents can be used, which facilitates the rapid assembly of a vast set of compounds., Syntheses of anilines occur through a variety of methods, most requiring transition metals or multiple steps. Here the authors disclose a protocol to form anilines from benzyl alcohols via an aza-Hock rearrangement that uses only a sulfonyl hydroxylamine and solvent.

Small and medium-sized enterprises (SEMs) are the important part of economic society whose innovation activities are of have great significance for building innovative country. In order to investigate how technological innovation (TI) and business model design (BMD) affect the business performance (BP) of SMEs, samples of 268 SMEs in the artificial intelligence industry and hierarchical regression models are used in the analysis. The results indicate that TI, BMD, and the matching of them have different effects on the innovation of SMEs of different sizes. These findings are helpful for enriching the theory of the fit between TI and BMD and providing theoretical guidance for the innovation activities in SEMs.

Cerium malate (CeMal) was tested as a corrosion inhibitor for AA2024-T3 in this work. Corrosion inhibition on bare AA2024-T3 indicated that the inhibiting effect was a result of the synergistic effect of cerium cations and maleic anions. The corrosion of AA2024-T3 was stagnated by greatly reducing the corrosion current when CeMal was present in NaCl solutions. CeMal was adsorbed on the surface of AA2024-T3 forming a protective film in the initial stage. Then, cerium cations transformed to cerium oxide/hydroxides, precipitating on the cathode sites to inhibit the further corrosion. The electrochemical impedance spectra results of the sol–gel coatings proved that CeMal was an effective corrosion inhibitor in the sol–gel coatings to provide corrosion protection for AA2024-T3.

The corrosion behavior of cupronickel alloy immersed in the simulated seawater in or without the presence of sulfate-reducing bacteria (SRB) was studied. The results of scanning electronic microscopy and electrochemical impedance spectra reveal that corrosion of the sample immersed in the simulated seawater with SRB was more serious than that immersed in the simulated seawater without SRB. The atomic force microscopy images show that after immersion for 15 days, the surface roughness of the sample in the simulated seawater with SRB was higher than that of the sample in the simulated seawater without SRB. The analysis of confocal laser scanning microscopy indicates that the average depth of the pits on the surface of the sample in the simulated seawater with SRB was almost twice deeper than that of the sample in the simulated seawater without SRB.

Raw coal is burned in furnaces or chain grate boilers. In this work, we studied the chamber combustion mechanism in a chain grate boiler (CGB) with a capacity of 20 t/hr. A mathematical model was built using Computational Fluid Dynamics (CFD). It was found that chamber combustion with swirl burners instead of grate firing has a positive effect on NO emissions. NO emissions dropped from 700 ppm in case 5 to 250 ppm in case 1. The calculated and measured NO emissions agreed well, with a discrepancy of less than 15%, except on plane 2 for four calculated cases. For the temperature field, the discrepancy between the measured and simulated values was below 12% for the four cases. These discrepancies between calculated and measured results are acceptable. This study provides a good idea for the design and reconstruction of CGBs. To reduce NO emissions, the reconstruction method can be used for CGBs instead of the grate firing system.

We have developed a facile and efficient Fe-catalyzed method for fabrication of porous carbons spheres with high graphitization degree (GNPCs) using glucose as carbon precursor at relatively low carbonization temperature. GNPCs not only have relatively large accessible ion surface area to accommodate greater capacity but also high graphitization degree to accelerate ion diffusion. As a typical application, we demonstrate that GNPCs exhibit excellent electrochemical performance for use in supercapacitors, with high specific capacity of 150.6 F g−1 at current density of 1 A g−1 and good rate capability and superior cycling stability over 10,000 cycles, confirming their potential application for energy storage. Moreover, it is believed that this method offers a new strategy for synthesis of porous carbons with high graphitization degree.

A facile surface modification method has been developed for improving the antifouling property of TFC membranes by immobilizing poly(ethylene glycol) (PEG) onto polyamide (PA) surface. PEG has been chelated and immobilized onto PA surface by ion-dipole interaction between ether oxygen atoms in PEG backbone and –COONa in PA layer. The resulting TFC membranes were characterized by ATR-FTIR, XPS, SEM, AFM, WLI, zeta potential as well as static contact angle. The changes in chemical composition and morphology of the membrane surface indicate the successful modification process. The permeation property of the PEG modified TFC membranes dependence on PEG concentration, treatment temperature and time has been investigated thoroughly. The optimized PEG modified membrane shows a NaCl rejection of 99.04%, higher than that (97.79%) of the virgin membrane. More importantly, PEG modified membrane exhibits much more improved organic fouling-resistance ability than control sample. Typically, after BSA fouling for 12 h, PEG modified membrane loses about 19% of the initial flux, much lower than that of the virgin PA membrane (40%). Furthermore, the flux recovery of the PEG modified membrane reaches about 95% after cleaning, much higher than that of the virgin PA membrane (79%). Therefore, this simple, rapid, environment-friendly and cost-effective modification approach will provide a method for mitigating the long-term fouling of reverse osmosis membrane.

A new method for the synthesis of γ-glutamylmethylamide is presented. Glutamic acid γ-methyl ester was used as substrate for γ-glutamylmethylamide synthesis catalyzed by Escherichia coli with γ-glutamyltranspeptidase activity. Reaction conditions were optimized by using 300 mM glutamic acid γ-methyl ester and 3,000 mM methylamine at pH 10 and 40 °C. Bioconversion rate of γ-glutamylmethylamide reached 87 % after 10 h. γ-Glutamyltranspeptidase was reversibly inhibited only when glutamic acid γ-methyl ester was above 300 mM.

Thin-film-composite (TFC) polyamide membranes with flux-enhancement were prepared by the interfacial polymerization of m-phenylenediamine with trimesoyl chloride on porous polysulfone support. The addition of 1,3-propanesultone (PS) in the organic phase is used to influence the interfacial polymerization process and the morphology of polyamide layer to improve water flux. FTIR, 1H NMR and UV spectra were performed to investigate the effect of PS on interfacial polymerization process. In order to study the forming mechanism of TFC membrane, the resulting TFC membranes were characterized by SEM, AFM, ATR-FTIR, XPS, as well as static contact angle. In comparison with conventional polyamide membrane, the TFC membranes fabricated with PS as the additive exhibit much more improved water flux without NaCl rejection decreasing. Notably, the optimal TFC membrane with 0.04% (wt/v) PS as the additive in organic phase shows the best performance with a NaCl rejection of 99.39% and a water flux of 48.57 L m−2 h−1 at 1.55 MPa, which has increased 41% compared to the value of the conventional TFC membrane.

The exposure of a high gloss polyurethane aircraft topcoat system with polyurethane intermediate coating and epoxy primer to strong ultraviolet radiation in Lhasa, Tibet was studied by using scanning electron microscopy (SEM), atomic force microscopy (AFM), attenuated total reflectance Fourier-transform infrared (ATR-FTIR), and X-ray photoelectron spectroscopy (XPS). Micro-flakes were found to form on the topcoat surface after exposure and the size and quantity of the flakes increased with the increase of the exposure time. The magnitude of micro-bulges and the topcoat roughness increased after a long exposure to sunlight. Flakes and micro-bulges resulted in the loss of the topcoat gloss. ATR-FTIR and XPS analysis indicated that chain scissions of the polyurea C=O group and the polyurethane C-O-C and CO-NH groups occurred, and the degradation products of NH and carbonyl groups formed due to the exposure. The breaking of the chemical structure of the polyurethane resulted in a decrease in its elasticity and in the adhesion of the flakes to its surface.