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The structure of samoquasine A has long been a subject of controversy, which was resolved only upon its successful total synthesis. We examined the structures of the associated compounds using the state-of-the-art SVM-M protocol. The method accurately discriminated all putative structures historically attributed to samoquasine A from a pool of 48 isomeric structures, confirming that samoquasine A is indeed identical to perlolidine. Furthermore, by applying the SVM-M protocol to an additional pool of 67 isomeric structures, we successfully assigned a yet unknown natural product, initially misidentified as perlolidine, as a novel oxime, (E)-3H-cyclopenta[c]quinolin-3-one oxime, representing the first reported cyclone oxime-quinoline natural product.

The catalytic activation of HCO3−/H2O2to generate reactive oxygen species could treat neutral or weak alkaline organic wastewater effectively. Based on the activation principle of HCO3−/H2O2and the advantages of natural tourmaline, four types of common tourmaline powders were investigated as catalysts to activate HCO3−/H2O2for the degradation of typical anionic (methyl orange: MO) and cationic (methylene blue: MB; rhodamine B: RhB) dyes in aqueous solution. Compared to magnesium-rich tourmaline, lithium-rich tourmaline and low Fe content tourmaline, higher activity was observed for high Fe content tourmaline (high-Fe TM) in the catalytic activation of HCO3−/H2O2to achieve dye degradation. Furthermore, high-Fe TM exhibited acceptable stability for activating HCO3−/H2O2for the degradation of dyes, and the co-existing ions in municipal tap water, temperature and pH had a weak influence on the catalytic activity of high-Fe TM. The degradation of dyes in the high-Fe TM/HCO3−/H2O2system was found to be initiated by typical reactive oxygen species, which are mainly originated from the catalytic activation of HCO3−/H2O2with high-Fe TM. Specifically, the Fe-based sites of high-Fe TM and the Fe ions dissolved with high-Fe TM co-activated HCO3−/H2O2through heterogeneous and homogeneous catalysis, respectively. The degradation of RhB was driven by OH and O2−, and the degradation of MB and MO was initiated by 1O2.

Solid-state lithium batteries hold great promise for next-generation energy storage systems. However, the formation of lithium filaments within the solid electrolyte remains a critical challenge. In this study, we investigate the crucial role of morphology in determining the resistance of garnet-type electrolytes to lithium filaments. By proposing a new test method, namely, cyclic linear sweep voltammetry, we can effectively evaluate the electrolyte resistance against lithium filaments. Our findings reveal a strong correlation between the microscopic morphology of the solid electrolyte and its resistance to lithium filaments. Samples with reduced pores and multiple grain boundaries demonstrate remarkable performance, achieving a critical current density of up to 3.2 mA cm–2and excellent long-term cycling stability. Kelvin probe force microscopy and finite element method simulation results shed light on the impact of grain boundaries and electrolyte pores on lithium-ion transport and filament propagation. To inhibit lithium penetration, minimizing pores and achieving a uniform morphology with small grains and plenty of grain boundaries are essential.

ABSTRACT This study focuses on developing a novel scheme for applying external active confinement to non-circular concrete elements that lack ductility using shape memory alloys (SMAs). A total of 13 [...]

Water oxidation is an endothermic reaction; BiVO4-based photoanodes with good photothermal and catalytic properties would be propitious to achieve efficient water oxidation in theory. Herein, NiO/amorphous carbon/BiVO4(NiO/C/BiVO4) and CoOx/amorphous carbon/BiVO4(CoOx/C/BiVO4) films were prepared by a facile candle flame roasting approach, and further investigated as photoanodes for solar water oxidation. Compared to BiVO4and C/BiVO4photoanodes, better water oxidation performance was achieved on the CoOx/C/BiVO4and NiO/C/BiVO4photoanodes. At 1.23 V vs.RHE, the water oxidation photocurrent of the CoOx/C/BiVO4and NiO/C/BiVO4photoanodes was 2.32 and 2.41 times higher than that of the BiVO4photoanode, respectively. The water oxidation activity on the CoOx/C/BiVO4and NiO/C/BiVO4photoanodes can be well maintained in the range of 84–87% after 120 min of constant reaction, which is higher than that on the BiVO4photoanode (43% activity retained). The NiO/C/BiVO4and CoOx/C/BiVO4photoanodes having higher water oxidation performance can be attributed to the following integrated effects. (1) The p–n heterojunction effect of NiO/BiVO4and CoOx/BiVO4drives the directional transfer of holes to CoOxor NiO and weakens the carrier recombination on BiVO4. (2) Amorphous carbon, CoOxand NiO absorb and convert the long wavelength light (λ> 510 nm) into heat to improve the co-catalysis performance of CoOxand NiO, and enable the NiO/C/BiVO4and CoOx/C/BiVO4photoanodes for efficient water oxidation. The present work provides two effective BiVO4-based photoanodes for photothermal-enhanced water splitting, which could inspire the design and development of similar materials for photothermal-enhanced solar water splitting.

Use of unmanned aerial vehicles (UAVs) for urban services has been an exciting topic in today's urban planning and management research. Most UAVs use unlicensed spectrum for remote control and communications. Their communication distance is limited within a few hundred meters; and the control channel is prone to interference. In comparison, urban cellular networks can cover a wide urban area with a low chance of interference, making them a viable alternative for UAVs on services that require real-time and reliable connections. In this article we provide a performance evaluation of this concept. We first address some key challenges in designing and implementing a UAV platform connected to cellular networks. The cellular networks include 4G and 5G. Then we use the platform to test the actual performance of 4G and 5G in urban areas with a focus on their signal strength and packet delay. A comparative analysis reveals the benefits 4G and 5G can bring to UAVs in urban flights.

Bending and folding are important stereoscopic geometry parameters of one-dimensional (1D) nanomaterials, yet the precise control of them has remained a great challenge. Herein, a surface-confined winding assembly strategy is demonstrated to regulate the stereoscopic architecture of uniform 1D mesoporous SiO2(mSiO2) nanorods. Based on this brand-new strategy, the 1D mSiO2nanorods can wind on the surface of 3D premade nanoparticles (sphere, cube, hexagon disk, spindle, rod, etc.) and inherit their surface topological structures. Therefore, the mSiO2nanorods with a diameter of ∼50 nm and a variable length can be bent into arc shapes with variable radii and radians, as well as folded into 60, 90, 120, and 180° angular convex corners with controllable folding times. Additionally, in contrast to conventional core@shell structures, this winding structure induces partial exposure and accessibility of the premade nanoparticles. The functional nanoparticles can exhibit large accessible surface and efficient energy exchanges with the surroundings. As a proof of concept, winding-structured CuS&mSiO2nanocomposites are fabricated, which are made up of a 100 nm CuS nanosphere and the 1D mSiO2nanorods with a diameter of ∼50 nm winding the nanosphere in the perimeter. The winding structured nanocomposites are demonstrated to have fourfold photoacoustic imaging intensity compared with the conventional core@shell nanostructure with an inaccessible core because of the greatly enhanced photothermal conversion efficiency (increased by ∼30%). Overall, our work paves the way to the design and synthesis of 1D nanomaterials with controllable bending and folding, as well as the formation of high-performance complex nanocomposites.

Precise tumor targeting and therapy is a major trend in cancer treatment. Herein, we designed a tumor acidic microenvironment activatable drug loaded DNA nanostructure, in which, we make a clever use of the sequences of AS1411 and i-motif, which can partially hybridization, and designed a simple while robust DNA d-strand nanostructure, in which, i-motif sequence was designed to regulate the binding ability of the AS1411 aptamer to target tumor, in the normal physiological environment, i-motif inhibits the targeting ability of AS1411. In the acidic tumor microenvironment, i-motif forms a quadruplex conformation and dissociates from AS1411, restoring the targeting ability of AS1411, only when acidic condition and tumor cell receptor are present, this nanostructure can be internalized by the tumor cells. Moreover, the structure change of this nanostructure can realize the release of loaded drug. This drug loaded A-I-Duplex DNA structure showed cancer cell and spheroid targeting and inhibition ability, which is promising in the clinical cancer therapy.

The precise and prompt determination of quality control indicators such as moisture, stilbene glycosides, and anthraquinone glycosides is crucial in assessing the quality of Polygoni Multiflori Radix. Near-infrared spectroscopy is a nondestructive analytical technique that offers a more desirable approach than traditional methods for assessing content levels. In this study, various spectral preprocessing techniques were used to preprocess the raw spectral data. The spectral data were correlated with the determination of three-component contents using the partial least squares regression (PLSR) method. Then different algorithms, such as competitive adaptive weighted sampling (CARS), Monte Carlo uninformative variable elimination (MCUVE), and random frog hopping (RF), were used for model simplification and feature selection. The data suggest that the first-order deconvolution derivative (1st Dev.) processing of the spectral data is superior to other methods in all three model evaluation metrics. The PLSR model for moisture, stilbene glycosides, and anthraquinone glycosides produced the calibration coefficient of determination (R2C) of 0.82, 0.52, and 0.58, the root mean square error of cross validation (RMSECV) of 0.91%, 0.77%, and 0.69%, the prediction coefficient of determination (R2P) of 0.72, 0.28, and 0.54, the root mean square error of prediction (RMSEP) of 0.65%, 0.81%, and 0.75%, and relative percentage differences (RPDs) of 1.7, 1.0, and 0.8. After optimizing the model using CARS, R2C increased by 0.15%, 0.41%, and 0.34%, RMSECV decreased by 0.53%, 0.32%, and 0.24%, R2P increased by 0.21%, 0.63%, and 0.35%, RMSEP decreased by 0.36%, 0.41%, and 0.31%, and RPD increased by 1.1, 0.9, and 0.6, significantly improving the predictive capacity of the model. This research provides a feasible method for rapid compliance testing of Polygoni Multiflori Radix. To further improve the model’s performance and applicability, it is necessary to continuously expand the sample set with different varieties and locations for wide variation.

HHP was a nonthermal technology which was widely used in food processing. In this study, HHP was used to process the peanut sprout juice and microbial load, physicochemical properties and antioxidant capacities of peanut sprout juice were found to be improved during 90-day storage. Compared with heat treatment (HT, 95 °C, 10 min), the treatment at 400–600 MPa resulted in greater microbiological stability. No more than 2 lg CFU/g of total plate count (TPC) was observed at 600 MPa for 5 min during a 90-day storage period at 4 °C. The significant negative correlation between the total number of colonies and resveratrol was confirmed, which has bactericidal and bacteriostatic effects. Additionally, resveratrol treated with HHP would degrade and generate new degradation products like p-methylphenol, resorcinol, oxidized resveratrol with higher DPPH scavenging rate, which resulted the higher antioxidation capacity in HHP treated peanut sprout juice. In a word, this study focused on the effect of HHP on peanut sprout juice and the possible degradation behavior of the bioactive resveratrol with HHP treatment, providing a promising processing technology for peanut sprout juice with higher quality.

AgNbO3-based antiferroelectric ceramics can be used to prepare dielectric ceramic materials with energy storage performance. However, their efficiency is much lower than that of relaxors, which is one of the biggest obstacles for their applications. To overcome this problem, AgNbO3ceramics co-doped with Eu3+and Ta5+at the A- and B-sites were prepared in this work. The Ag0.97Eu0.01Nb0.85Ta0.15O3sample has a Wrof 6.9 J/cm3and an ηof 74.6%. The ultrahigh energy storage density and efficiency of Ag0.97Eu0.01Nb0.85Ta0.15O3has been ascribed to the synergistic effect of the increase in the breakdown electric field, the enhancement of antiferroelectric stability, the construction of multiphase coexistence, and the modification of the domain structure morphology. The Ag0.97Eu0.01Nb0.85Ta0.15O3ceramic is expected to be one of the options for preparing dielectric capacitors.

A carbon nanotube/poly(ethyl 2‐cyanoacrylate) (CNT/PECA) composite electrode was developed for enhanced amperometric detection. The composite electrode was fabricated on the basis of water‐vapor‐initiated polymerization of a mixture of CNTs and ethyl 2‐cyanoacrylate in the bore of a piece of fused silica capillary. The morphology and structure of the composite were investigated by scanning electron microscopy, Fourier transform infrared spectroscopy, X‐ray diffraction, and thermogravimetric analysis. The results indicate that the CNTs were well dispersed and embedded throughout the PECA matrix to form an interconnected CNT network. The analytical performance of this unique CNT‐based detector has been demonstrated by separating and detecting six flavones in combination with capillary electrophoresis. The advantages of the CNT/PECA composite detector include lower operating potential, higher sensitivity, low expense of fabrication, satisfactory resistance to surface fouling, and enhanced stability; these properties indicate great promise for a wide range of applications.

Proteomics will contribute greatly to the understanding of gene functions in the post-genomic era. In proteome research, protein digestion is a key procedure prior to mass spectrometry identification. During the past decade, a variety of electromagnetic waves have been employed to accelerate proteolysis. This review focuses on the recent advances and the key strategies of these novel proteolysis approaches for digesting and identifying proteins. The subjects covered include microwave-accelerated protein digestion, infrared-assisted proteolysis, ultraviolet-enhanced protein digestion, laser-assisted proteolysis, and future prospects. It is expected that these novel proteolysis strategies accelerated by various electromagnetic waves will become powerful tools in proteome research and will find wide applications in high throughput protein digestion and identification.

The purpose of this study was to report an unusual case of severe microphthalmos, together with an orbital cyst and huge ocular surface dermolipoma.