RUSSIAN JOURNAL OF GENERAL CHEMISTRY
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2021
·Vol. 91
·期 4
·726-731
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IF 0.868
Xu Y.,Hu Y.,Bao Q.,Zhang J.,Liu B.,Zhang Z.,Zhang Q.,Zhang H.
Copper phyllosilicate has been synthesized from a solution of sodium silicate and copper nitrate by co-precipitation under acidic conditions followed by reduction under H 2 flow for using it as the Cu/SiO 2 catalyst. The catalyst has been characterized by XRD, XPS, FTIR and Raman spectra, EDS, BET, and TEM. It is confirmed that only copper phyllosilicate and SiO 2 exist in the catalyst precursor, and there has been no CuO. Physical and chemical properties of Cu/SiO 2 catalyst have been evaluated. The Cu/SiO 2 catalyst has not only a large specific surface area and abundant mesopores but also the advantages of high dispersion of copper nanoparticles and the combination of Cu 0 and Cu + . The catalyst demonstrates high activity and selectivity in the reaction of 2-butanol dehydrogenation to methyl ethyl ketone.
研究领域:
催化化学
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材料科学
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物理化学
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纳米材料
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有机合成
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JOURNAL OF ALLOYS AND COMPOUNDS
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2026
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IF 6.7
Wenkun Chen,Zhen Xu,Jin Dai,Yitao Liu,Jianyong Yu,Shude Liu,Bin Ding
Materials with excellent thermal resistance and infrared stealth capability have broad application potential in aerospace, national defense and military industries. Ceramic fiber aerogels are widely adopted infrared stealth materials owing to their outstanding high temperature resistance, low thermal conductivity, low bulk density and chemical stability. However, as advanced equipment continues to evolve, the environmental temperature encountered by some stealth materials exceeds 1500 °C. Existing aerogel materials are prone to structural collapse under such harsh conditions. This issue remains unresolved. Herein, ceramic fiber materials are successfully fabricated through a novel spinning process and an intracrystalline structure design strategy within fibers. These materials maintain excellent mechanical properties at 1700 °C. Subsequently, infrared stealth devices with excellent comprehensive performance are obtained by assembling three layered components. The bottom component is an aerogel with a self-locking micro/nanofiber structure. The middle component is an aerogel with a binary architecture composed of micro/nanofibers and SiC nanoparticles. The top component is an aluminum foil bonded to the middle component. Under an ultra-high temperature of 1700 °C, the cold surface exhibits an infrared radiation temperature of only 55 °C. Successful infrared stealth is achieved in extreme environments. After exposure to large temperature gradients from liquid nitrogen for 30 min to 1700 °C for 30 min, the devices still maintain excellent mechanical properties. Furthermore, they withstand 1000 cycles of compressive and shear deformation at 50% strain without dissociation under high-frequency vibration. This new generation of infrared stealth devices with outstanding structural stability, temperature resistance and thermal insulation capability can provide reliable safety protection for equipment and personnel.
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Fermentation-Basel
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2026
·Vol. 12
·期 2
·102
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IF 4.1
Xun Fu,Qingyu Nie,Xiang Li,Penghao Tan,Tingting Feng,Chunmei Xiong,Wenling Zhang,Yan Zhang,Sujin Li,Lixin Zhang
In recent years, there has been substantial global progress in screening yeasts for fermenting various specialty fruits, especially non-Saccharomyces species known for their contributions to aroma enhancement. This study focused on mature fruits and soil samples collected from orchards located in the main production region ofC. reticulatacv. ‘Dahongpao’ (CRCD) in China, with the objective of isolating specialized non-Saccharomycesyeasts suitable for producing CRCD fruit wine. After enrichment cultivation, seven characteristic yeast strains were isolated and purified. These isolates were identified asCandida parapsilosis,Meyerozyma caribbica,Candida quercitrusa, andMeyerozyma guilliermondiithrough a combination of microscopic morphology and molecular biology methods, which also includedPichia fermentans,Pichia kudriavzevii, andPichia kluyveri. The strains’ fermentation potential, ethanol production rates, and tolerance levels were assessed, leading to the selection ofCandida parapsilosis,Candida quercitrusa,Pichia fermentans,Pichia kudriavzevii, andPichia kluyverifor further fermentation experiments. The commercial yeast La-Ma was used as a control. Analysis of volatile organic compounds (VOCs) in the fruit wine samples was performed using Gas Chromatography–Ion Mobility Spectrometry (GC-IMS). A total of 42 different VOCs were identified, with esters being the most prevalent. The fingerprint profiles demonstrated notable differences between the fruit wine samples fermented with selected yeasts and those fermented with commercial yeasts. Principal component analysis (PCA) indicated thatPichia kluyveridisplayed the most significant divergence from both commercial and other selected yeasts. The samples contained notable VOCs such as 2-methyl-1-butanol, pentanal, 3-methyl-2-butenal, propyl acetate, butyl acetate, isobutyl acetate, isopentyl acetate, and 3-methyl-2-butenyl acetate, while the methanol production was observed to be lower compared to other samples. Consequently, this strain has the potential to produce distinctive fruit wine.
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CARBOHYDRATE RESEARCH
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2026
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IF 2.5
Wang Zhao,Jiansong Chen,Haishun Du,Zhiqiang Pang,Weiqi Wei,Xuejun Pan
Furfural is a pivotal intermediate in the biomass conversion. Therefore, the production of furfural from xylose or xylose-rich biomass has received extensive attention. Herein, a series of boron phosphate solid acid catalysts (BPs) were synthesized by self-assembly and high-temperature calcination, and used for the production of furfural from xylose or xylose-rich biomass. The results showed that the synthesized BPs was spherical nanoparticles and containing both Lewis acid and Brønsted acid sites, which was excellent for xylose conversion to furfural. The maximum furfural yield of this work was 82.8 % and achieved through 95.7 % xylose conversion by using 20 mg BP 1.25 at a reaction temperature of 130 °C for 120 min with a LiBr⋅3H 2 O/dichloromethane (DCM) biphasic system. Noteworthy, the recycling experiments indicated that both the BP 1.25 catalyst and the LiBr⋅3H 2 O can be reused at least four times with a furfural yield remaining ≥61.7 %. Last but not least, the prepared BP 1.25 catalyst also displayed high efficiency for xylose-rich natural biomass such as corncob and bagasse conversion into furfural. The work not only developed a new system for easy conversion of xylose into furfural, but also realized the high yield production of furfural from natural biomass without components separation.
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PubMed
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FLUID PHASE EQUILIBRIA
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2023
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IF 2.6
Xiaomin Qiu,Huaqing Qi,Mengjin Zhou,Zhaoyou Zhu,Yinglong Wang,Jingwei Yang,Hengjun Gai
Sufficient and accurate physical property data is the basis for thermodynamic analysis and process simulation analysis. Reliable thermodynamic model data is essential for the study of extractive distillation separation of azeotropic mixtures. The vapor-liquid equilibrium data of 2-butanol alcohol-ethylene glycol and cyclohexane-butyl butyrate were measured by using a reliable experimental device, namely a modified Rose vapor-recirculating-type equilibrium still. The effects of 12 solvents on the relative volatility of the azeotrope of cyclohexane, 2-butanol alcohol and water were calculated, and ethylene glycol was selected as the best solvent. On this basis, the contribution of different atom pairs and atoms to the interaction between ethylene glycol and cyclohexane/2-butyl alcohol/water was compared and studied, and the reason why ethylene glycol can separate cyclohexane-2-butyl alcohol-water was analyzed. The thermodynamic model parameters obtained from the vapor-liquid equilibrium experiment were used to simulate the extractive distillation process, and total annual cost optimization was performed to improve the process accuracy. Overall, this study improves the application potential of phase equilibrium data in azeotropic separation technology, and establishes a reliable data and model foundation for the sustainable development of 2-butyl alcohol and cyclohexane.
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ACS Omega
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2023
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IF 4.1
Yuzhu Li,Kangzhuo Yang,Zhanglan He,Zhipeng Liu,Jialing Lu,Dong Zhao,Jia Zheng,Michael C. Qian
Electronic nose (E-nose) technology is frequently attempted to simulate the human olfactory system to recognize complex odors. Metal oxide semiconductors (MOSs) are E-noses’ most popular sensor materials. However, these sensor responses to different scents were poorly understood. This study investigated the characteristic responses of sensors to volatile compounds in a MOS-based E-nose platform, using baijiu as an evaluation system. The results showed that the sensor array had distinctive responses for different volatile compounds, and the response intensities varied depending on the sensors and the volatile compounds. Some sensors had dose–response relationships in a specific concentration range. Among all the volatiles investigated in this study, fatty acid esters had the greatest contribution to the overall sensor response of baijiu. Different aroma types of Chinese baijiu and different brands of strong aroma-type baijiu were successfully classified using the E-nose. This study provided an understanding of detailed MOS sensor response with volatile compounds, which could be further applied to improve the E-nose technology and its practical application in food and beverages.
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JOURNAL OF CHEMICAL AND ENGINEERING DATA
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2023
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IF 2.6
Mei Dong,Wenjing Shi,Jian Chen,Danni Zhao,Mengmeng Yang,Wenxin Yang,Wei Deng,Wensheng Li,Weiping Luo
In this study, the solubilities of phthalic acid (PA) and o-toluic acid (o-TA) in methanol, ethanol, n-propanol, iso-propanol, n-butanol, iso-butanol, sec-butanol, and tert-butanol were measured by the laser dynamic method at atmospheric pressure (101.3 kPa) in the range of 292.25–353.35 K. The experimental results show that the solubilities of PA and o-TA in eight alcohols are positively correlated with temperature. In the four solvents methanol, ethanol, n-propanol, and n-butanol, the solubilities of PA and o-TA decrease with the increase of the number of carbon atoms in the main chain, and the order of solubility of PA and o-TA in butanol isomers from high to low is tert-butanol, sec-butanol, n-butanol, and iso-butanol. The solubility ratio of o-TA and PA in iso-butanol is the largest, indicating that iso-butanol could best separate the two. The experimental data were correlated by using the Apelblat model, the Buchowski–Ksiazczak λh model, and the modified no n-random two liquid activity coefficient model. The calculated solubilities were in good fit with the measured results. The Akaike information criterion was used to evaluate the selected model. The thermodynamic properties were calculated, and the main contributor of standard molar Gibbs energy of PA and o-TA in eight alcohols is enthalpy, about 54.66 to 68.34%.
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Science Bulletin
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2022
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IF 20.577
Pengxiang Zhang,Yushui Fu,Xin Zhang,Xihua Zhang,Bao-Wen Li,Ce-Wen Nan
Chemically exfoliated nanosheets have exhibited great potential for applications in various electronic devices. Solution-based processing strategies such as inkjet printing provide a low-cost, environmentally friendly, and scalable route for the fabrication of flexible devices based on functional inks of two-dimensional nanosheets. In this study, chemically exfoliated high- k perovskite nanosheets (i.e., Ca 2 Nb 3 O 10 and Ca 2 NaNb 4 O 13 ) are well dispersed in appropriate solvents to prepare printable inks, and then, a series of microcapacitors with Ag and graphene electrodes are printed. The resulting microcapacitors, Ag/Ca 2 Nb 3 O 10 /Ag, graphene/Ca 2 Nb 3 O 10 /graphene, and graphene/Ca 2 NaNb 4 O 13 /graphene, demonstrate high capacitance densities of 20, 80, and 150 nF/cm 2 and high dielectric constants of 26, 110, and 200, respectively. Such dielectric enhancement in the microcapacitors with graphene electrodes is possibly attributed to the dielectric/graphene interface. In addition, these microcapacitors also exhibit good insulating performance with a moderate electrical breakdown strength of approximately 1 MV/cm, excellent flexibility, and thermal stability up to 200 ℃. This work demonstrates the potential of high- k perovskite nanosheets for additive manufacturing of flexible high-performance dielectric capacitors.
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Solar RRL
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2023
·Vol. 7
·期 6
·2201047
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IF 7.9
Yuan Yu,Peng Xu,Huitian Du,Qian Zhou,Yukun Wu,Yuying Hao,Junfeng Ren,Zhiyong Pang,Zhaolai Chen,Shenghao Han
In recent years, nickel oxide (NiO x ) is widely used as an excellent hole transport layer for the inverted perovskite solar cells (PSCs), due to its decent hole conductivity, easy processability, and low cost. However, the photovoltaic performance and stability of NiO x -based PSCs are severely limited by the poor perovskite/NiO x interface. Herein, a versatile coupling agent di(dioctylpyrophosphato) ethylene titanate (NDZ-311) is introduced to improve the performance of NiO x -based inverted PSCs by suppressing nonradiative recombination and strengthening charge transfer at the perovskite/NiO x interface. Moreover, the chemical reaction between NDZ-311 and NiO x reduces the surface hydroxyl groups of NiO x film and avoids direct contact between perovskite and NiO x film, which mitigate material degradation caused by high-valence Ni ions and hydroxyl groups. As a result, the average power conversion efficiency (PCE) of inverted PSCs is enhanced from ≈18.01% to ≈19.92% and a maximum PCE of ≈20.39% is obtained. The unencapsulated PSC with NDZ-311 modification maintains 87.65% of their initial performance after 400 h aging test in air, much better than the control device (49.41% after 400 h). The work demonstrates the potential application of NDZ-311 for commercial PSCs, considering NDZ-311 is a cheap industrial material.
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JOURNAL OF MOLECULAR LIQUIDS
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2023
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IF 6
Xinyu Ma,Pan Du,Ben Niu,Jiaxuan Zhang,Huaisong Yong,Xianru He
Though the mechanism of temperature-induced lower critical solution temperature (LCST) in water is clear for the classic homopolymer poly( N -isopropylacrylamide) (PNIPAM), the LCST of other homopolymer or copolymer remains to be understood. In this work, a novel random copolymer poly(2-hydroxyethyl- co -methyl acrylate) (P(HEA- co -MA)) was prepared. The LCST of the copolymer P(HEA- co -MA) can vary from 11 °C to 65 °C by adjusting flexibly the ratio of the two monomers, showing a broad tunable range. The experimental results showed that the balance of hydrogen bond bridge formed by P(HEA- co -MA) in water and the hydrophobic interaction between polymers can cause the LCST transition of P(HEA- co -MA). An interesting observation is that the sharp phase transition (cosolvency) of P(HEA- co -MA) exists when a rather small amount of alcohol or water is added in polymer solutions at constant temperatures. Moreover, it was found that the increase of LCST is correlated with the increase of alcohol concentration in the water-rich regime, but the decrease of upper critical solution temperature (UCST) is related to the increase of water concentration in the alcohol-rich regime. This work shed light on the understanding of cosolvency by studying the solution behavior of copolymer P(HEA- co -MA) in mixed solvents, which can be of interest for the design of stimuli-responsive polymer materials by variation in solvent composition.
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CATALYSIS LETTERS
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2023
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IF 2.8
Xiang Yuchen,Zhang Huiming,Zhang Jingyi,Xu Qiong,Liu Xianxiang,Yin Dulin
Comprehensive use of available biomass, especially low-cost forestry waste to produce bioenergy, materials have great meaning for realization of green and sustainable chemical processes. In this work, forestry sawdusty waste (SD) was used to produce biochar (SDBC-P) via a H 3 PO 4 assisted hydrothermal carbonization method. And a novel zirconium-coordinated biochar catalyst Zr-SDBC-P has been prepared by self-assembly method. Characterization results revealed that hydrothermal carbonization in the presence of H 3 PO 4 promoted the formation of oxygen-containing functional groups (–COOH, Ar–OH) which were used as ligand to obtain high contents of Lewis acid − base sites (Zr 4+ –O 2− ). Zr-SDBC-P-4 showed satisfactory catalytic activity in synthesis of bioderived γ-valerolactone (GVL) from ethyl levulinate (EL). EL conversion of 98.2% and GVL selectivity of 85.4% were obtained within 5 h at 170 °C. In addition, Zr-SDBC-P-4 displayed outstanding chemical stability. There was no obvious decrease of GVL yield after being used for six cycles. Overall, this work offered a viewpoint to design catalyst from value-added utilization of biomass waste. Graphical Abstract
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ACS Catalysis
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2023
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IF 12.9
Xugang Yang,Zaihao Yuan,Minghao Zhou,Feng Chen,Bo-Qing Xu,Hui Shi
Lewis acidic heterogeneous catalysts are known to be active for transfer hydrogenation of carbonyl compounds, which occur naturally or can be derived from renewable feedstocks. While previous studies have explored a myriad of Zr-based catalytic systems toward the Meerwein–Pondorf–Verley (MPV) reductions, few have determined intrinsic, site-specific rates under strict kinetic control across a sufficiently wide range of process conditions, causing misconceptions about the true potentials of these catalysts for the targeted transformations. Here, we present a quantitative assessment on the intrinsic activities of four types of Zr catalysts that are purportedly promising candidates for the MPV reductions; the selected catalysts contain active Zr sites within diversified local coordination and secondary solvating environments. A comprehensive kinetic study of ethyl levulinate (EL) MPV reduction in 2-butanol, combined with in situ quantitative titration of the active sites by selective poisoning with alkylphosphonic acid titrants of Lewis acid sites during the reaction, reveals dramatic differences in the relative fraction of active sites (13–78% of total Zr) and turnover rates (>300-fold) among the studied catalysts. Mechanistically, the hydride shift invariably remains as the sole rate-limiting step, regardless of the catalyst; the free energy barriers in both first-order and zero-order kinetic regimes and kinetic isotope effects, however, differ significantly among the catalysts. Through mechanism-based rate equations and transition-state-theory treatments, we further delineate that the wide variations in enthalpic and entropic components not only suggest disparate transition state structures and energetics but also reflect varying adsorption thermodynamics that are influenced by both reactant coordination at and solvent restructuring near the active sites.
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危险品化学品经营许可证（带存储）