APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
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2020
·Vol. 126
·期 7
·1-9
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IF 1.81
He Bing,He Wenhui,Wang Yawen
Semiconductor photocatalyst as a new type of green and sustainable energy material has extensively used in wastewater and gas treatment. In this work, we prepared Pt/h-BN/BiOBr composite by an alcohol-soluble hydrolysis-assisted photoreduction method. The photocatalytic activity was evaluated by the degradation of bisphenol A under simulated sunlight, and the degradation efficiency of BiOBr, h-BN/BiOBr, Pt/BiOBr, and Pt/h-BN/BiOBr were 55.13%, 74.91%, 89.00%, and 98.54%, respectively. The results showed single composited with h-BN or Pt could improve the photocatalytic performance of BiOBr, while double composited with h-BN and Pt could play a synergistic effect on further improving the activity. The interaction between h-BN and BiOBr was electrostatic interactions, and that Pt as a plasma metal was coupling with BiOBr due to its localized surface plasmon resonance (LSPR) effect. The composition, morphology, optical property, and separation efficiency of photo-induced carriers and dominant active radicals were investigated. Based on the results, a possible mechanism was proposed. The excellent photocatalytic activity of Pt/h-BN/BiOBr composite photocatalyst could be attributed to the broadened light-response range after Pt loading, and enhanced electron–hole separation efficiency due to the electron capturer role of Pt and the hole transfer function of h-BN.
研究领域:
环境科学
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材料科学
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化学工程
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DOI
高影响因子
JOURNAL OF ORGANIC CHEMISTRY
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2017
·
IF 4.849
Jian Cheng,Jun Sun,Jiekuan Yan,Song Yang,Pengcheng Zheng,Zhichao Jin,Yonggui Robin Chi
The metal-free catalytic functionalization of aromatic sp2-carbons and benzylic sp3-carbons remains challenging. Here we report a carbene-catalyzed functionalization of the 3-methyl sp3-carbon attached to 2-formyl-indoles. The reaction proceeds through an NHC-bound o-quinodimethane as the key intermediate generated from 2-formyl-3-methylindoles under oxidative conditions. Reactive ketones are found to be effective substrates to produce substituted hydropyrano[3,4-b]indoles in good to excellent yields.
研究领域:
有机化学
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合成化学
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DOI
高影响因子
CANADIAN JOURNAL OF CHEMICAL ENGINEERING
·
2013
·Vol. 92
·期 5
·851-860
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IF 1.003
Zhenhua Pan,Qizhou Cai,Qiang Luo,Xinwei Li
The mechanism and kinetics of synergetic effect in TiO 2 /O 3 /UV process on H-acid degradation were investigated. The experimental results showed that H-acid removal rate of TiO 2 /O 3 /UV process was the highest among TiO 2 /UV, O 3 /UV and TiO 2 /O 3 /UV processes. The investigation of reactions with suitable active species scavengers confirmed that H-acid was mainly oxidised by ozone and holes on TiO 2 in the TiO 2 /O 3 /UV process. The recombination between holes and electrons in TiO 2 reduced in the presence of ozone, as indicated by fluorescence emission spectra. Moreover, the intermediates generated during H-acid oxidation in various processes were analysed by LC/MSD trap. It is proposed that H-acid was oxidised to polyhydroxy aromatics, benzene carboxylic acids and quinoids in the first step. Then, saturated aliphatics carboxylic acids were formed and mineralised to inorganic compounds through the Photo-Kolbe reaction. Finally, a kinetic study on TiO 2 /UV, O 3 /UV and TiO 2 /O 3 /UV processes was conducted and it was confirmed that both ozonation and photocatalytic activity were improved in TiO 2 /O 3 /UV process because of the synergetic effect.
研究领域:
环境科学
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化学工程
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DOI
高影响因子
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
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2022
·Vol. 2022
·期 33
·e202200316
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IF 3.261
Yong Wang,Hui Wang,Qifan Yang,Shihua Xie,Hongjun Zhu
Graphical Herein, palladium(II)-catalyzed halogenation of 2-phenylquinazolines using N -halosuccinimides as halogen sources was described via C−H activation under mild reaction conditions. A series of halogen-substituted 2-arylquinazolines were synthesized through C−H functionalization. An efficient quinazoline-assisted ortho -halogenation of 2-arylquinazolines has been developed using N -halosuccinimides as halogen sources with Pd(II)-catalyzed C−H bond activation. No additional ligand and oxidant are required. This protocol is highly regioselective and applicable to a broad range of quinazoline substrates bearing different functional groups, giving yields of up to 98 %. The mechanism of the quinazoline ortho -halogenation was investigated by comprehensive experimentation.
研究领域:
有机化学
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合成化学
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DOI
高影响因子
Journal of Materials Chemistry A
·
2024
·
IF 10.7
Yuhui Huang,Yehan Tao,Qingqing Wang,Jian Du,Jinwen Hu,Jie Lu,Yanna Lv,Haisong Wang
To develop an industrial zeolite-based catalyst for efficient furfural production, the acidity, pore structure, and electronic properties of H-β zeolite were modulated by synergistic deatomization and atomic implantation treatments. The dealumination effectively decreased the intrinsic aluminum-related Lewis and Brosted acid sites, thus decreasing the occurrence of unwanted side reactions. Meanwhile, the removed skeleton aluminum can create voids for the following atomic implantation of introducing higher valent-state niobium species, which would provide new kinds of catalytic active sites, increase the average pore size by distorting the zeolite skeleton, and enhance the interaction with reactant molecules by acting as more electron deficient centers. In a single-phase water/γ-valerolactone reaction system, the optimum catalyst can efficiently convert both xylan and xylose with a conversion of 100 % at a medium temperature of 130 ℃ within 3 hours. Compared with the furfural yield over untreated H-β (12.7%), the yield over deAlβ/Nb(20%) catalyst was greatly enhanced by 54% with xylose as raw material. The catalyst can be recovered by simple cleaning and thermal regeneration and then reused. The proposed post-treatment strategy could maintain the integrity of the zeolite structure, ensure uniform and stable metal dispersion under harsh conditions, manage the complexity and cost of the preparation process, and most importantly, optimize the catalytic performance. Addressing these issues is essential for improving the efficiency and practical application of industrial zeolite catalysts by this general approach and benefiting industrial furfural production.
研究领域:
化学工程
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催化材料
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DOI
高影响因子
Lubricants
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2024
·Vol. 12
·期 5
·163
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IF 3.1
Yunqi Fang,Yang Sun,Fengqin Shang,Jing Zhang,Jiayu Yao,Zihan Yan,Hangyan Shen
Van der Waals heterostructures with incommensurate contact interfaces show excellent tribological performance, which provides solutions for the development of new solid lubricants. In this paper, a facile electrostatic layer-by-layer self-assembly (LBL) technique was proposed to prepare multi-layer van der Waals heterostructures tungsten disulfide/hexagonal boron nitride (vdWH WS2/h-BN). The h-BN and WS2were modified with poly (diallyldimethylammonium chloride) (PDDA) and sodium dodecyl benzene sulfonate (SDBS) to obtain the positively charged PDDA@h-BN and the negatively charged SDBS@WS2, respectively. When the mass ratio of PDDA to h-BN and SDBS to WS2were both 1:1 and the pH was 3, the zeta potential of PDDA@h-BN and SDBS@WS2were 60.0 mV and −50.1 mV, respectively. Under the electrostatic interaction, the PDDA@h-BN and SDBS@WS2attracted each other and stacked alternately along the (002) crystal plane forming the multi-layer (four-layer) vdWH WS2/h-BN. The addition of the multi-layer vdWH WS2/h-BN (1.0 wt%) to the base oil resulted in a significant reduction of 33.8% in the friction coefficient (0.104) and 16.8% in the wear rate (4.43 × 10−5mm3/(N·m)). The excellent tribological property of the multi-layer vdWH WS2/h-BN arose from the lattice mismatch (26.0%), a 15-fold higher interlayer slip possibility, and the formation of transfer film at the contact interface. This study provided an easily accessible method for the multi-layer vdWH with excellent tribological properties.
研究领域:
材料科学
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摩擦学
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纳米技术
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DOI
高影响因子
APPLIED ORGANOMETALLIC CHEMISTRY
·
2016
·Vol. 30
·期 8
·680-683
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IF 2.452
Lulu Wang,Minxin Yang,Xiaochong Liu,He Song,Lu Han,Wenyi Chu,Zhizhong Sun
A bidentate-chelation assistant palladium-catalyzed direct C-H cyanation of picolinamides with TMSCN is described. The reaction of various derivatives gave the corresponding cyanated products in moderate to good yields under mild conditions. In addition, the cyanated product could transform into some valuable functional groups in good yields. Copyright © 2016 John Wiley & Sons, Ltd.
研究领域:
有机化学
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药物化学
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高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2023
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IF 22.1
Haiying Xu,Zhaoliang Wang,Hehua Liao,Dongmiao Li,Jinni Shen,Jinlin Long,Wenxin Dai,Xuxu Wang,Zizhong Zhang
Photocatalytic converting CO 2 into C 2 products is highly desirable but is extremely sensitive to catalyst structure. In this work, Ti-H species and oxygen vacancies are simultaneously integrated on hydrogenated SrTiO 3 surface by thermally treating with NaBH 4 , which promotes the activation of CO 2 into HCOO - and CO* intermediates. The proximity of oxygen vacancies and Ti-H species contributes to the C-C coupling of intermediates into acetylene (C 2 H 2 ) products. To the best of our knowledge, this is the first example for the photocatalytic CO 2 reduction into C 2 H 2 main products. The optimal hydrogenated SrTiO 3 has the C 2 H 2 yield of 39.0 μmol·g −1 with a 76.0 % selectivity among C 2 products. Therefore, this work provides an approach of designing the adjacent active sites for photocatalytic CO 2 conversion into C 2+ products.
研究领域:
材料科学
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环境科学
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产品关联
DOI
高影响因子
JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY
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2024
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IF 3.1
Guanru Chen,Fengjian Chu,Shuheng Zhang,Wangyu Li,Shiwen Zhou,Wei Wei,Weiwei Chen,Xiaozhi Wang,Lei Yue,Hongru Feng,Yanli Cui,Yuanjiang Pan
C–H bond ortho-substitution reaction has always been a significant and challenging topic in organic chemistry. We proposed a synthesis method based on microwave plasma torches. High-resolution mass spectrometry was used to monitor rapid reaction products. 2-Alkylbenzimidazole can be formed through the reaction of phenylnitrenium ion and nitriles on a millisecond scale. This reaction can achieve the one-step formation of benzimidazoles from benzene ring single-substituted compounds without the addition of external oxidants or catalysts. A similar C–H bond activation reaction can be accomplished with ketones. Meanwhile, the microwave plasma reactor was modified, and the resulting 2-methylbenzimidazole was successfully collected, indicating the device has good application potential in organic reactions such as C–H bond activation reaction.
研究领域:
有机化学
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合成化学
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分析化学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2023
·
IF 5.7
Mao Chen,Bingbing Fan,Haoyuan Lei,Zijie Song,Shaojun Zhang,Hailong Wang,Rui Zhang,Hongxia Li,Yongqiang Chen
Large size high density h-BN/ZrO 2 composites (ø = 110 mm, h = 15 mm) were rapidly prepared by spark plasma sintering (SPS) with sintering cycle 20 min. The effects of additives on the mechanical properties , microstructure evolution, and corrosion resistance of the h-BN/ZrO 2 composites were studied. The Al 2 O 3 , MgO , SiO 2 , La 2 O 3 and ZrO 2 rapidly formed heterogeneous eutectic crystals under the action of SPS. The low eutectic compounds significantly promoted the diffusion of h-BN or ZrO 2 , also increased the density. The flexural strength of h-BN/ZrO 2 composites could reach 196.31 MPa, and the apparent porosity was only 0.42 %. The additives are combined with zirconia to form a high viscosity eutectic, whose corrosion resistance to molten steel is obviously better than that of single ZrO 2 . The corrosion depth of h-BN/ZrO 2 composites was only 114 µm after corroded in molten steel at 1550 °C for 80 min. The comprehensive properties of h-BN/ZrO 2 composites were obviously improved by appropriate additives.
研究领域:
材料科学
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陶瓷工程
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产品关联
DOI
高影响因子
Surfaces and Interfaces
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2025
·
IF 6.3
Ziqian Ding,Xiaolin Qiu,Huaxuan Liu,Lingli Gu
Functional form-stable phase change materials (FPCMs) offer great promise for thermal management in transport packaging due to their stability after phase change cycle and the extension of service life. However, challenges remain in enhancing thermal conductivity and energy storage efficiencies. In this study, a magnetically aligned h-BN-embedded superporous carbon foam-based FPCM containing paraffin (M-BN-CPCMs) was fabricated via a foam polymerization method followed by high-temperature carbonization. A super-porous hydrogel (SPH) precursor was used to construct a robust, highly porous carbon skeleton to accommodate more PCMs. To further enhance thermal conductivity, h-BN was functionalized with Fe 3 O 4 nanoparticles, and the resulting BN-Fe 3 O 4 was magnetically oriented within the carbon skeleton using a synchronous magnetization process. This novel design achieved a thermal conductivity improvement of over 90% compared to SPH. Additionally, the synergistic photothermal conversion effect achieved by the magnetic nanoparticles and carbon skeleton resulted in an outstanding photothermal conversion efficiency of approximately 90% for M-BN-CPCMs. Notably, the incorporation of BN-Fe 3 O 4 increased pore sizes, enabling higher paraffin loading capacity. The M-BN-CPCMs with large holes exhibit a remarkable phase change enthalpy of 154.9 J/g, demonstrating excellent energy storage capability, which surpasses that of superporous carbon foam skeleton-based FPCMs (CPCMs). The optimized M-BN-CPCMs demonstrated superior thermal energy storage, faster thermal charging rates, and improved thermal regulation, effectively reducing temperature fluctuations within insulated packaging. These findings underscore the potential of M-BN-CPCMs as a groundbreaking solution for energy storage and thermal management in transport packaging, addressing critical challenges in the field.
研究领域:
材料科学
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能源工程
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产品关联
DOI
高影响因子
INORGANIC CHEMISTRY COMMUNICATIONS
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2024
·
IF 4.4
Xuyong Tang,Fengxi Li,Sijun Huang,Li Xu,Lei Wang,Yi Guo
Nicotinamide-adenine dinucleotide (NADH) as biomimetic units combined with copper ion to form laccases mimics (Cu-NADH). Cu-NADH has the enhanced activity of copper center to mediate aryl C–H amination using air as green oxidants. It could successfully catalyze oxidative coupling between different aromatic compounds and 4-phenylurazole (yield: 72 ∼ 91 %). Recycling catalytic ability (up to 6 times) showed its excellent stability. The Cu-NADH nanozyme was certificated to catalyze C–H amination effectively, and highlighted that it was a proper way to design catalysts according to enzyme-like catalyzing non-natural reaction.
研究领域:
生物化学
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催化化学
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环境科学
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产品关联
DOI
高影响因子