As a rising new member of carbon allotropes, graphdiyne has shown great potential in various fields due to its fascinating properties. Herein, a controlled two-step hydrothermal route was employed to convert hydrogen-substituted gamma-graphdiyne into two functional derivatives: graphdiyne oxides (OGDY) and graphdiyne oxide quantum dots (OGDYQD). Systematic characterization revealed distinct differences in morphology, chemical structure, and optical properties between precursors and derivatives. Especially, the existence of alkyne bonds was demonstrated through evidence from Fourier transform infrared spectroscopy (FTIR), photoluminescence spectroscopy (PL), and selective oxidation experiments, which provides new insights for the characterization of graphdiyne materials. Moreover, we identified an oxidation-locking phenomenon governing selective alkyne oxidation at specific sites during synthesis. The oxidation-locking feature endowed significant application potential upon both derivatives: OGDY exhibited excellent photocatalytic ability in the degradation of cationic dyes, achieving efficiency similar to 5-200 higher than those of other carbon-based materials; while OGDYQD could achieve ultrasensitive electrochemical detection of methyl orange with a limit of detection (LOD) as low as 0.032 mu M, as well as serve as an excellent catalyst, which was comparable to metal catalysts, for the hydrogenation of 4-nitrophenol. This work provides fundamental insights into sp-carbon reactivity while delivering practical platforms for multiple applications.

Constructing effective charge separation and migration channels to strengthen the reaction activity of photocatalytic materials still poses a considerable challenge in the field of photocatalysis. Within research endeavor, a 2D/2D Bi4TaO8Cl/g-C3N4 heterojunction photocatalyst featuring a close interfacial connection was successfully prepared using a high-temperature calcination technique. It was then applied to achieve efficient photocatalytic reduction of CO2 to CH3OH. According Xe lamp irradiation, the Bi4TaO8Cl/g-C3N4 composite with an optimized ratio (BTCN-30) exhibited excellent CO2 reduction performance, achieving a methanol yield of 417.4 mu mol & sdot;g- 1 & sdot;h- 1, which was 3.08 times and 2.25 times higher than Bi4TaO8Cl and g-C3N4, separately, along with moderate cycling stability. Based on theoretical calculations along with experimental results, the enhanced photocatalytic efficiency in the CO2-to-CH3OH conversion process should be attributed to the increased ability to absorb visible light, the strengthened interaction with reactant molecules by the unique 2D/2D heterostructure, and the formation of the S-scheme heterojunction facilitated improved charge transfer kinetics and significantly lowered interfacial transfer resistance. This study presents an innovative approach and theoretical foundation for designing highly efficient photocatalysts aimed at achieving the conversion of CO2 into CH3OH.

The relentless scaling of process nodes imposes ever-tighter limits on permissible defect sizes in silicon, the foundational substrate of modern microelectronics. Void-type defects are especially detrimental, degrading gate-oxide integrity and device yield in metal-oxide-semiconductor field-effect transistors (MOSFETs). In this work, we characterize the size, areal density, and spatial distribution of non-cleanable light point defects (LPDNs) associated with crystal-originated particles (COPs) on Czochralski-grown silicon (Cz-Si) wafers using localized light-scattering inspection. We further elucidate their dependence on dissolved nitrogen and oxygen. The measurements reveal that in nitrogen-doped Cz-Si, the COP size diminishes with increasing nitrogen concentration, whereas elevated oxygen produces the opposite trend. COP areal density likewise decreases with nitrogen and increases with oxygen. We attribute these opposing tendencies to the competition between nitrogen-vacancy and nitrogen-oxygen complex formation during crystal growth and cooling. Spatial mapping shows that large COPs concentration near the wafer center, consistent with the thermal history and radial gradients in vacancy supersaturation. These results clarify how nitrogen and oxygen jointly modulate COP nucleation and growth in Cz-Si, and they provide actionable guidance for defect engineering to safeguard gate-oxide reliability at advanced technology nodes.

By adjusting the Bi3+/Cl− feed ratio and introducing acrylamide (AM), a hydrothermal system containing BiOCl, basic bismuth nitrate (BBN), and polyacrylic acid (PAA) was obtained. The formation of BBN suppressed the further growth and crystallization of BiOCl, while PAA altered the local electronic environment of BiOCl through coordination with Bi3+. Subsequent calcination and acid washing led to clear differences in structure and surface properties. During calcination, PAA decomposed and BBN gradually transformed into BiOCl, accompanied by the formation of more oxygen vacancies. During acid washing, BBN was selectively removed together with part of the associated PAA, resulting in changes in surface composition and pore structure. Although the two post-treatment routes differed in their structural effects and photocatalytic pathways, both promoted the separation and transfer of photogenerated charge carriers and improved the visible-light photocatalytic degradation of rhodamine B (RhB) and rhodamine 6G (Rh6G) over BiOCl.

As a rising member of carbon allotropes, graphdiyne holds significant research value in terms of both its properties and applications. For properties, there is currently a lack of methods to assess the polymerization degree of graphdiyne, which is crucial to establish a standardized evaluation system for graphdiyne products; for applications, the application potential of graphdiyne materials with a low polymerization degree has not been fully explored. Herein, a biphenyl-group capping method has been engineered through the introduction of 4-ethynyl-1,1'-biphenyl (4-Eb) during the synthesis of hydrogen-substituted graphdiyne (GDY). 4-Eb could operate as a "capping agent" in the cross-coupling reaction, which tuned the polymerization degree of GDY. Accordingly, a strategy for relatively quantitatively assessing the polymerization degree of GDY via the precise analysis of Fourier transform infrared spectra (FTIR) has been developed and verified by various characterization methods. Moreover, the biphenyl-group capping could improve the separation efficiency of photogenerated carriers and introduce an intermediate energy level, which was helpful to expand the practical applicability of low-polymerization-degree graphdiyne materials in photocatalysis. Specifically, the photocatalytic degradation rate of the optimal sample for rhodamine B (RhB) was enhanced by 13.0-fold relative to GDY, and that for tetracycline hydrochloride (TCH) was increased by 4.9-fold.

Cleavage of hexopyranose to short-chain carbohydrates plays crucial roles in carbon metabolism and energy supply. Currently, the carbon–carbon bond scission of hexopyranose involves two types of reaction: the widely distributed retro-aldol reaction and the transketo-like reaction observed in Bifidobacteria. Here we report the discovery and characterization of metalloenzyme Art22, which is involved in the sugar moiety modification of aurantinin B (ART B), an antibacterial agent from Bacillus. Art22 adopts a TIM-barrel fold, enabling the activation of 4-keto ART B into potent antibiotic ART B via rapid isomerization. In addition, it protects the ART-producing Bacillus by detoxifying cellular ART B to ART B1–B3 via slow oxidative cleavage of the 3-keto hexopyranose to short-chain carbohydrates and CO2. Guided by structural, mutagenic and computational studies, we reveal an anhydride-mediated mechanism for Art22-catalysed oxygenation reactions, which expands the catalytic repertoire of TIM-barrel enzymes and adds an oxidative path for hexopyranose cleavage. Hexopyranose cleavage is a crucial step in carbon metabolism. Here the authors report the discovery and characterization of metalloenzyme Art22, which is involved in the sugar moiety modification of aurantinin B, an antibacterial agent from Bacillus.

Metal-organic frameworks (MOFs), with tunable morphologies and porous architectures, show great potential in photocatalysis. A variety of MOFs can be synthesized by changing the types of metal ions and organic ligands. However, fewer studies have explored the influence of the metal-to-ligand molar ratio on the catalytic performance of the resulting MOF-related products. In this work, capsule-shaped NH2-MIL-68(In)/InOOH composites were synthesized by adjusting molar ratios of In(NO3)3 to 2-aminoterephthalic acid. Time-dependent characterization revealed sequential crystallization: rod-shaped NH2-MIL-68(In) initially formed in the solution, followed by the in-situ growth of InOOH nanowires on its surfaces via excess indium ions, ultimately constructing a Z-scheme heterojunction. The optimized NM/InOOH (8:1) composite exhibited a larger specific surface area and extended light absorption. The Z-scheme configuration significantly promoted charge carrier separation efficiency while maintaining strong redox potentials of the photoinduced holes and electrons, thereby resulting in 5-8-fold improvement in degradation rates for four dyes (AOII, RhB, MB, and Rh6G), highlighting its broad photocatalytic applicability.

Carbon quantum dots (CQDs) decoration have been widely acknowledged as promising strategy in photocatalysis, yet in-depth understanding of the effect of different functionalized CQDs on CO2 photocatalytic reduction is still lacked. Herein, three kinds of functionalized CQDs, i.e. carboxylic CQDs (CCQDs), amino CQDs (NCQDs) and sulfonated CQDs (SCQDs), were homogeneously anchored on amino-rich g-C3N4 (U1W1-CN) to investigate their CO2 reduction behaviors under simulated solar-light illumination. Structural analysis demonstrated that potential amide covalent bonds formed between U1W1-CN and CCQDs, and noncovalent conjugations might exist between U1W1-CN and SCQDs, while strong electrostatic attraction between U1W1-CN and NCQDs. Performance tests showed CQDs decoration greatly enhanced the CO2 reduction activity, with 7%CCQDs/U1W1-CN exhibiting the optimal CO and CH4 productions of 40.94 mu mol g(-1) and 2.2 mu mol g(-1) under 4 h light irradiation, markedly higher than those of 7%SCQDs/U1W1-CN and 7%NCQDs/U1W1-CN. After comprehensive analysis, it was found that CCQDs decoration endowed U1W1-CN with better CO2 adsorption and activation. And due to the potential amide covalent bonds formed between CCQDs and U1W1-CN, 7%CCQDs/U1W1-CN delivered the largest electron density and most abundant COOH- intermediates, contributing much to its superior CO2 reduction activity over 7%NCQDs/U1W1-CN and 7%SCQDs/U1W1-CN. It is expected that the critical role of functional group modulation on CQDs in enhancing CO2 photocatalytic reduction revealed in this work can provide valuable insights into the rational design of more advanced photocatalysts for targeted reactions.

The influence of morphology on the photocatalytic performance of catalysts is a critical aspect that merits further exploration. This study successfully synthesized a series of CdIn2S4/self-assembled 2 S 4 /self-assembled g-C3N4 3 N 4 photocatalysts with varying morphologies and structures via an in-situ deposition approach. The unique combination of g-C3N4 ' s 3 N surface curvature and the radial-spreading layers significantly contributed to the superior photocatalytic activity observed in the optimal sample. This sample achieved an impressive 91.3 % degradation of methyl orange within 30 min and an 81.6 % degradation of tetracycline hydrochloride in 120 min. These degradation rates surpassed those of pristine g-C3N4 3 N 4 by factors of 13.12 and 1.14, respectively. The findings of this research offer a promising strategy for designing highly active heterojunction photocatalysts tailored for pollutant removal and guiding the uniform deposition of CdIn2S4. 2 S 4 .

BiOCl has garnered considerable attention recently. However, its relatively wide bandgap and poor separation efficiency of charge carriers limit its application in the visible light range. Introducing oxygen vacancies (OVs) and constructing heterojunctions are both considered as viable modification approaches. In this study, oxygen vacancy-rich BiOCl/Bi24O31Cl10 heterojunctions were synthesized using glycine as the fuel by a one-pot self-propagation method. Variations in the amount of fuel led to differences in OV concentration and heterojunction composition in the prepared samples. The XRD pattern, FTIR spectra and EDS confirmed the formation of BiOCl/Bi24O31Cl10 heterojunctions. The XPS and ESR spectra proved the existence of oxygen vacancies. The BET results showed that the sample prepared with an appropriate amount of glycine exhibited a larger specific surface area. The most effective OVs-BiOCl/Bi24O31Cl10 composite demonstrated improvements in degrading rhodamine B (RhB), showing 8.09 and 17.96 times greater efficiency compared to BiOCl and Bi24O31Cl10, respectively. It achieved 93% dye degradation within 30 minutes.

The X-ray Photoelectron Spectroscopy (XPS) technique can provide information about the chemical states of various elements on the sample surface and the peak intensities and positions of their spectra. The thickness of thin films can be calculated by utilizing this information and the equation for photoelectron signals. This paper introduces three methods for handling the equation of photoelectron signals: direct solving method, substrate-ratio method, and angle-ratio method. Their derivation processes are analyzed, and the results indicate that these three methods have different accuracies and applicability ranges. The direct-solving method has the widest applicability but the lowest accuracy. The substrate-ratio method has the most limited applicability range, being able to calculate the thickness of thin films only on substrates of infinite thickness, and the effective attenuation length lambda of the composition of film and substrate composition needs to be similar. However, it is least affected by instrumental and carbon contamination errors, thus having the highest calculation accuracy. The angle-ratio method has a moderate applicability range and calculation accuracy, and it can be used without considering the limitation of the substrate layer. However, the variation in the emission angle theta significantly affects the calculation accuracy. Researchers can consider the above factors comprehensively when calculating the thickness of thin films using XPS data.

The porous structure formed by the interweaving of yarns in textiles is favorable for sound absorption. However, the absorption of sound waves by porous materials conforms to the law of linear response, which leads to poor sound absorption of textiles in the low-frequency range. It is usually necessary to increase the thickness to improve the low-frequency acoustic absorption performance of textiles, which does not meet the performance requirements of lightness, thinness, width and strength. This work proposes a method to increase the acoustic absorption performance based on acoustic-electric conversion and yarn resonance effect. In the form of a woven spacer fabric structure, different parts of the structure were prepared using nylon and PVDF yarns with different triboelectric sequences to realize acoustic-electric conversion between dielectric materials. Control samples woven with the same material were also prepared. Further, the resonance frequency of the yarns was modulated by controlling their tension to change the resonant frequency corresponding to the maximum acoustic-electric conversion efficiency and sound absorption peak. It was found that fabrics composed of two different materials had better sound absorption than fabrics composed of only one material. This is because the larger triboelectric sequence difference between materials results in more charge transfer, which favors acoustic-electric conversion and acoustic energy consumption. A significant acoustic absorption peak at 390 Hz with a peak value of about 0.05 was observed for a fabric with a thickness of about 4 mm after tension adjustment. This study demonstrates that acoustic-electric conversion between dielectric yarns and proper tension control improves the acoustic absorption efficiency and provides a reference for the development of structures based on this novel acoustic absorption mechanism.

Traditional hydrogel dressings generally have poor mechanical properties and stability when subjected to external stress due to the undesirable chain entanglement structure of their single valence bond compositions. Therefore, it is particularly important to develop a type of gel dressing with good mechanical strength, stability, and environment-friendly monitoring. In this work, a transparent, pH-sensitive, highly stretchable, and biocompatible anthocyanidin ionogel dressing was prepared, realizing green and accurate detection. Attributed to the antibacterial activity of the ionic liquid, the biocompatibility of the pectin, and the ability to scavenge free radicals of the anthocyanidin, the ionogel dressing exhibited excellent re-epithelialization in the 14 day wound healing process. Besides, changes in pH values monitoring of the ionogel over 3 days coincided with normal wound exudate. The obtained ionogel also showed good water retention, swelling properties, mechanical stretchability, and 5 week stability, illustrating great potential in wound dressings.

Element doping is considered as a feasible strategy to develop efficient photocatalysts. In this study, a Ce-doped CdIn2S4 photocatalyst was prepared through a modified coprecipitation method. During the synthesis of Ce-doped CdIn2S4, the CeO2 nanorods were gradually reduced by the decomposition products of thioacetamide (TAA), and mainly existed as Ce(III) in the supernatant. This resulted in a large increase in the specific surface area of the as-obtained products, providing more exposed active sites for the reactant. Additionally, a trace amount of Ce was doped into the lattice of the CdIn2S4, resulting in a significant effect on the band structure. By tracing the roles of CeO2 during the synthesis process, a possible reaction mechanism was proposed. Benefiting from the synergistic advantages of the structural and compositional features, the optimal sample showed enhanced photocatalytic activities for the degradation of methyl orange (94.6% within 25 min) and tetracycline hydrochloride (85.6% within 120 min). The degradation rates were 13.3 times and 2.7 times higher than that of pristine CdIn2S4. This work may provide a strategy for designing metal element doped photocatalysts with good activity for pollutant removal.

In most of the research about graphitic carbon nitride (g-C3N4), g-C3N4 is prepared through the calcination of nitrogen-rich precursors. However, such a preparation method is time-consuming, and the photocatalytic performance of pristine g-C3N4 is lackluster due to the unreacted amino groups on the surface of g-C3N4. Therefore, a modified preparation method, calcination through residual heating, was developed to achieve rapid preparation and thermal exfoliation of g-C3N4 simultaneously. Compared with pristine g-C3N4, the samples prepared by residual heating had fewer residual amino groups, a thinner 2D structure, and higher crystallinity, which led to a better photocatalytic performance. The photocatalytic degradation rate of the optimal sample for rhodamine B could reach 7.8 times higher than that of pristine g-C3N4.

Morphology control and multi-elemental doping are considered two effective strategies to improve the photocatalytic performance of graphitic carbon nitride (g-C3N4). Herein, a mild and convenient method was applied to synthesize S/Cd co-doped g-C3N4 nanorods with excellent photocatalytic performance. Under visible irradiation, the optimized sample could degrade 89.7 % methylene blue (MB) in 50 min and 96.5 % rhodamine B (RhB) in 15 min, whose degradation rates were 2.2 times and 23.2 times higher than that of pristine g-C3N4, respectively. Comprehensive investigation revealed that the presence of nanorods and co-doping of S and Cd led to a larger specific surface area, more nitrogen vacancies, and modification of band structure, which could considerably enhance the photocatalytic performance.

The stereochemistry of aurantinin was determined by spectroscopic and computational analysis with the assistance of biosynthetic studies. The latter method provided critical evidence for the assignment of the configuration of the 3-ketosugar moiety.

目前的自然语言处理技术的发展,依然面临如下问题:(1)不同的自然语言处理机制之间缺乏融合;(2)自然语言处理技术与人工智能研究的其他技术缺乏彼此融合;(3)基于大数据的自然语言处理技术的运作必须以"剥削"人类的智能为前提;(4)基于大数据的自然语言处理技术缺乏灵活处理隐喻、反讽、双关等修辞现象的能力.这些问题所涉及的主要哲学问题有:(1)语言是外部世界的表征,还是言说者内部世界的表征?(2)语言中的规则,究竟是先验的,还是经验的?(3)语言表征与言说者的心理活动之间的关系为何?(4)与语言表征有关的认知构架,在多大程度上需要被"具身化"?

与西方近代哲学传统的关系不仅是理解《存在与时间》的关键,也是其成败得失的重要参照.然而,反叛西方哲学传统的姿态、问题意识的别具一格、全新的术语体系使得其与西方近代哲学传统之间的关系隐而不显.就此而言,写于《存在与时间》前后时期的《时间概念史导论》与《康德书》则展示了其与胡塞尔哲学和康德哲学的深刻关联:存在问题产生于对现象学的内在批判,时间问题则可以追溯到康德的先验哲学.因而它们共同构成了《存在与时间》内在思想的完整性,不仅是理解基础存在论的重要切口,也揭示了其内在矛盾和海德格尔思想转向的根本原因.

Ternary composites involved graphitic carbon nitride (g-C3N4) have gained scientific interest in recent years. Herein, we report a series of ternary composites containing AgCl nanoparticles, Au nanoparticles, and g-C3N4 (AgCl/Au/CN) via a two-step chemical deposition method. In this semiconductor-metal-semiconductor structure, AgCl nanoparticles can absorb organic anions, as well as form a Z-scheme heterojunction combined with g-C3N4; Au nanoparticles can play a role in the separation of photogenerated carriers. These features allow AgCl/Au/CN to exhibit excellent photocatalytic degradation performance for anionic dyes. When the molar ratios of AgCl and Au to g-C3N4 are 1% and 0.5%, respectively, the optimal AgCl/Au/CN sample can achieve effective degradation for Rhodamine B within 25 min under visible-light irradiation of relatively low intensity. (C) 2021 Elsevier B.V. All rights reserved.