Journal of Biobased Materials and Bioenergy
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2017
·Vol. 11
·期 6
·562-567
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IF 0.975
Wang Lan-Ying,Zhuang Jun-Ping,Yu Kai-Rong,Wu Shu-Bin
Sn-Beta zeolite is a promising catalysts for isomerization of glucose to fructose, which is a key step in the conversion of biomass to various platform chemicals. Herein, Sn-Beta-H zeolite was efficiently prepared via hydrothermal synthesis by using Al-Beta. Finally, the product was
heated to 423 K for 48 h then calcined at 550 °C for 6 h to obtain Sn-Beta-H sample. The results of XRD patterns confirmed that the prepared catalyst had both microporous and mesoporous; N2 sorption isotherms showed that the main pore size centered at around 3.5 nm; TD-DTG revealed
that the Sn-Beta-H zeolite had good thermal stability with the peaks on the DTG curves was 283 °C; FTIR and UV-Vis spectra also successfully indicated that tin substitution into the zeolite framework. The effects of various reaction conditions including reaction temperature, reaction time
and the amount of catalyst on glucose conversion and fructose yield and selectivity were investigated. Under optimized operating conditions, 10% glucose solution in 40 ml water, catalyst (4 g), at 120 °C for 2 h, resulting in fructose yield of 30.8% and selectivity of 61.3%. Moreover,
Sn-Beta-H zeolite could be easily recovered and efficiently reused without significant loss in its catalytic activity.
研究领域:
催化化学
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生物质转化
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材料科学
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DOI
高影响因子
Journal of the American Chemical Society
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2024
·
IF 14.4
Liu Lin,Yunming Xu,Yiting Han,Ruikun Xu,Tongyue Wang,Zemin Sun,Zhenhua Yan
A deep understanding of the mechanism for the spin-magnetic effect on O–H cleavage is crucial for the development of new catalysts for water oxidation. Herein, we designed and synthesized the crystalline Fe-DABDT and Co-DABDT (DABDT = 2,5-diaminobenzene-1,4-dithiol) and optimized an effective magnetic moment to explore the role of the spin-magnetic effect in the regulation of water oxidation activity. It can be found that the OER activity of the catalyst is positively correlated with its effective magnetic moment. Under the external magnetic field, Fe-DABDT with more spin single electrons has a stronger spin-magnetic response to water oxidation than Fe/Co-DABDT and Co-DABDT. The increase in OER current of Fe-DABDT is nearly 2 times higher than that of Co-DABDT. Experimental and density functional theory studies show that magnetized Fe sites could realize nucleophilic reaction, accelerate the polarization of electron spin states, and promote the polar decomposition of O–H and the formation of the O–O bond. This study provides mechanistic insight into the spin-magnetic effect of oxygen evolution reaction and further understanding of the spin origin of catalytic activity, which is expected to improve the energy efficiency of hydrogen production.
研究领域:
化学
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材料科学
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催化反应
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产品关联
DOI
PubMed
高影响因子
APPLIED ORGANOMETALLIC CHEMISTRY
·
2014
·Vol. 28
·期 9
·673-677
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IF 2.017
Limin Ren,Wenyi Chu,Dinghui Guan,Yanjun Hou,Man Wang,Xiaobin Yuan,Zhizhong Sun
A simple and efficient route for the preparation of terphenyl derivatives via palladium-catalyzed sequential directed C―H arylation/Suzuki–Miyaura cross-coupling in ‘one-pot’ has been developed. 4,4′-(Cyclohexane-1,1-diyl)diphenol is an essential ligand. This reaction can tolerate a series of functional groups and provides the terphenyl derivatives in moderate to good yield. Copyright © 2014 John Wiley & Sons, Ltd.
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
Food Analytical Methods
·
2015
·Vol. 8
·期 10
·2605-2611
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IF 1.956
Peng Juan,Song Shanshan,Liu Liqiang,Kuang Hua,Xu Chuanlai
In order to develop highly sensitive immunoassays for detecting the major peanut allergen, Ara h 2, we prepared six monoclonal antibodies (mAb) with high affinity to Ara h 2. Using mAb 5 as a capture antibody and HRP-labeled mAb 1 as a detection antibody, a sandwich enzyme-linked immunoassay (ELISA) was established with a limit of detection (LOD) of 0.02 ng/mL. An immunochromatographic strip based on these two mAbs was also established with a LOD of 1 ng/mL. Both tests showed high specificity in cross-reactivity experiments. Sample analyses indicated that these two immunoassays were feasible, accurate, and highly sensitive for measuring allergen Ara h 2 of food.
研究领域:
食品科学
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免疫学
·
生物化学
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2024
·
IF 10.8
Zhisong Liu,Haomiao Xu,Yurui Fan,Wenjun Huang,Feng Yu,Zan Qu,Naiqiang Yan
Ruthenium single-atom catalysts have great potential in ammonia-selective catalytic oxidation (NH3–SCO); however, the stable sp3 hybrid orbital of NH3 molecules makes N(sp3)–H dissociation a challenge for conventional symmetrical metallic oxide catalysts. Herein, we propose a heterogeneous interface reverse atom capture strategy to construct Ru with unique asymmetric Ru1N2O1 coordination. Ru1N2O1/CeO2 exhibits intrinsic low-temperature conversion (T100 at 160 °C) compared to symmetric coordinated Ru-based (280 °C), Ir-based (220 °C), and Pt-based (200 °C) catalysts, and the TOF is 65.4 times that of Ag-based catalysts. The experimental and theoretical studies show that there is a strong d–p orbital interaction between Ru and N atoms, which not only enhances the adsorption of ammonia at the Ru1N2O1 position but also optimizes the electronic configuration of Ru. Furthermore, the affinity of Ru1N2O1/CeO2 to water is significantly weaker than that of conventional catalysts (the binding energy of the Pd3Au1 catalyst is −1.19 eV, but it is −0.39 eV for our material), so it has excellent water resistance. Finally, the N(sp3)–H activation of NH3 requires the assistance of surface reactive oxygen species, but we found that asymmetric Ru1N2O1 can directly activate the N(sp3)–H bond without the involvement of surface reactive oxygen species. This study provides a novel principle for the rational design of the proximal coordination of active sites to achieve its optimal catalytic activity in single-atom catalysis.
研究领域:
催化化学
·
材料科学
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产品关联
DOI
PubMed
高影响因子
Journal of the Taiwan Institute of Chemical Engineers
·
2019
·
IF 3.834
Yunchao Feng,Miao Zuo,Ting Wang,Wenlong Jia,Xiaoyu Zhao,Xianhai Zeng,Yong Sun,Xing Tang,Tingzhou Lei,Lu Lin
Production of 5-hydroxymethylfurfural (HMF) from glucose with high yield remains a big challenge. Thereinto, assembling catalysts with outstanding performance is the bottleneck at the current stage. In this study, effective catalysts were synthesized by loading SO 4 2− /ZrO 2 (SZ) on a series of H + zeolites to investigate the catalytic dehydration of glucose into HMF. Among all the catalysts applied, 2-SZ-HM-550 (HZSM-5 with Si/Al molar ratios of 80∼150, calcined at 550 °C) gave the yields of HMF 41.32%, 61.14%, 54.67% and 40.71% in 4 applied reaction systems, respectively. Moreover, HMF with desirable yield was obtained while other carbohydrates were dehydrated catalyzed by 2-SZ-HM-550, such as fructose, sucrose, inulin and starch.
研究领域:
化学工程
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催化科学
✓ 已验证
DOI
高影响因子
Catalysts
·
2018
·Vol. 8
·期 8
·326
·
IF 3.465
Peng Sun,Jun Zhang,Wenxiu Liu,Qi Wang,Wenbin Cao
In this paper, the Langmuir-Hinshelwood (L-H) model has been used to investigate the kinetics of photodegradation of gaseous benzene by nitrogen-doped TiO2(N-TiO2) at 25 °C under visible light irradiation. Experimental results show that the photoreaction coefficientkpmincreased from 3.992 × 10−6mol·kg−1·s−1to 11.55 × 10−6mol·kg−1·s−1along with increasing illumination intensity. However, the adsorption equilibrium constantKLdecreased from 1139 to 597 m3·mol−1when the illumination intensity increased from 36.7 × 104lx to 75.1 × 104lx, whereas it was 2761 m3·mol−1in the absence of light. This is contrary to the fact thatKLshould be a constant if the temperature was fixed. This phenomenon can be attributed to the breaking of the adsorption-desorption equilibrium by photocatalytically decomposition. To compensate for the disequilibrium of the adsorption-desorption process, photoreaction coefficientkpmwas introduced to the expression ofKLand the compensation form was denoted asKm.KLis an indicator of the adsorption capacity of TiO2whileKmis only an indicator of the coverage ratio of TiO2surface. The modified L-H model has been experimentally verified so it is expected to be used to predict the kinetics of the photocatalytic degradation of gaseous benzene.Keywords:modified L-H model;N-TiO2;photocatalytic degradation;benzene
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2016
·
IF 7.145
Wei Ji,Guofeng Liu,Zijian Li,Chuanliang Feng
For CH···O hydrogen bonds in assembled structures and the applications, one of the critical issues is how molecular spatial structures affect their interaction modes as well as how to translate the different modes into the macroscopic properties of materials. Herein, coumarin-derived isomeric hydrogelators with different spatial structures are synthesized, where only nitrogen atoms locate at the ortho, meso, or para position in the pyridine ring. The gelators can self-assemble into single crystals and nanofibrous networks through CH···O interactions, which are greatly influenced by nitrogen spatial positions in the pyridine ring, leading to the different self-assembly mechanisms, packing modes, and properties of the nanofibrous networks. Typically, different cell proliferation rates are obtained on the different CH···O bonds driving nanofibrous structures, implying that tiny variation of the stereo-position of nitrogen atoms can be sensitively detected by cells. The study paves a novel way to investigate the influence of isomeric molecular assembly on macroscopic properties and functions of materials.
研究领域:
材料科学
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生物学
·
医学
✓ 已验证
DOI
PubMed
高影响因子
CEMENT AND CONCRETE RESEARCH
·
2024
·
IF 10.9
Binmeng Chen,Xu Fang,Yuyang Zhao,Zongjin Li
In recycling and reusing construction waste, carbonation of recycled concrete fine (RCF) has been successfully applied to produce value-added products, such as silica nanoparticles, via the breaking of calcium silicate hydrate (C-S-H) structure and condensation of silicate chains. However, the intricacies of carbonation of RCF with varying calcium to silicon (C/S) ratios and their implications on the size of generated silica nanoparticles remain unknown. In this work, we developed an optimized carbonation method at high water to solid ratio to fabricate silica nanoparticles from C-S-H with different C/S ratios. The particle size of silica nanoparticles was found to gradually decrease with the increased C/S ratio of C-S-H. Since as C/S ratio increased, silicate in Q 3 state shifted to Q 1 state and the silicate chain became shorter, shifting from long-range, disordered to short-range, ordered. As the disordered self-seeding growth of long silicate chains derived from C-S-H continued, the Si-O-Si network of silica nanoparticles became chaotic, leaving more unreacted Si-OH on its surface. On the contrary, the short silicate chains displayed higher possibility of condensation, making nanoparticles with a smaller diameter.
研究领域:
材料科学
·
环境工程
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产品关联
DOI
高影响因子
CEMENT AND CONCRETE RESEARCH
·
2025
·
IF 13.1
Haochuan Wang,Xin Liu,Chong Wang,Wei Wang,Jinxiang Hong,Pan Feng
Ultra-early mechanical properties are critical for shotcrete performance, significantly influenced by ettringite and calcium silicate hydrate (C-S-H) formed during the initial hydration stage and free water. This study investigates the individual and synergistic effects of these phases on mechanical behavior using equivalent cement pastes. In this system, cement was entirely replaced with dolomite particles of matching size distribution, with the controlled introduction of free water, ettringite, and C-S-H. The validity of these equivalent systems was confirmed through comprehensive characterization. Mechanical performance was subsequently evaluated using compression, shear, Vickers hardness and nanoindentation tests. Results revealed that free water remarkably weakened the mechanical properties, whereas both ettringite and C-S-H enhanced strength by reducing voids and reinforcing weak particle interfaces. Ettringite primarily contributed to interparticle friction, while C-S-H enhanced cohesion at interfaces including dolomite-dolomite, dolomite-ettringite and ettringite-ettringite contacts. When co-existing, C-S-H formed within the porous ettringite network, not only establishing a multi-scale filling structure but also stabilizing the dolomite-ettringite skeleton. These findings advance our understanding of the early-age mechanical development of shotcrete and highlight the potential of equivalent cement systems as robust tools for research into cementitious materials.
研究领域:
土木工程
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材料科学
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产品关联
DOI
高影响因子
CATALYSIS LETTERS
·
2018
·Vol. 148
·期 11
·3445-3453
·
IF 2.911
Li Xia,Dong Hao,Wang Bo,Lv Jun,Xu Guangqing,Wang Dongmei,Wu Yucheng
Firstly, h-CdS/c-CdS homojunction was prepared by solvothermal method with controlling the Cd-to-S molar ratio. Then, the MoS 2 /h-CdS/c-CdS nanocomposites were constructed by ultrasonic method with different MoS 2 amount. The experimental results showed that when the molar ratio of Cd and S was 1:1 and the amount of MoS 2 was 1.5 wt%, the MoS 2 /h-CdS/c-CdS nanocomposites exhibited excellent photocatalytic performance for hydrogen evolution under visible light. The total amount of hydrogen evolution was 3753.12 µmol for 5 h, and its average hydrogen evolution rate was 40.79 mmol h −1 g −1 with an apparent quantum efficiency of 38.16% irradiated at 420 nm, which was about 7.3 times when compared with the h-CdS/c-CdS homojunction (Cd:S = 1:8). The enhanced photocatalytic performance of MoS 2 /h-CdS/c-CdS could be attributed to the improved specific surface area and formation of well bonded interface structure, which not only enhanced the response to visible light but also decreased the recombination rates of photogenerated charge carriers. Graphical Abstract
研究领域:
材料科学
·
光催化
✓ 已验证
DOI
高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
·
2021
·
IF 3.171
Xiao Zhao,Xuan Shi,Zhongshun Chen,Long Xu,Chengyi Dai,Yazhou Zhang,Xinwen Guo,Dongyuan Yang,Xiaoxun Ma
A series of ZnO-ZrO 2 solid solutions with different Zn contents were synthesized by the urea co-precipitation method, which were coupled with H-ZSM-5 zeolite to form bifunctional catalysts. As a new benzene alkylation reagent, syngas was used instead of methanol to realize the efficient conversion of syngas and benzene into toluene and xylene. A suitable ratio of ZnO-ZrO 2 led to the significant improvement in the catalytic performance, and a suitable amount of acid helped to increase the selectivity of toluene/xylene and reduce the selectivity of the by-products ethylbenzene and C 9 + aromatics. The highest benzene conversion of 89.2% and toluene/xylene selectivity of 88.7% were achieved over 10% ZnO-ZrO 2 &H-ZSM-5 (Si/Al = 23) at a pressure of 3 MPa and a temperature of 450 °C. In addition, the effect of the zeolite framework structure on product distribution was examined. Similar to the molecular dynamics of aromatic hydrocarbons , H-ZSM-5 zeolites comprise 10-membered-ring pores, which are beneficial to the activation of benzene; hence, the conversion of benzene is higher. H-ZSM-35 and H-MOR zeolites exhibited small eight-membered-ring channels, which were not conducive to the passage of benzene; hence, the by-product ethylbenzene exhibits a higher selectivity. The distance between the active centers of the bifunctional catalysts was the main factor affecting the catalytic performance, and the powder mixing method was more conducive to the conversion of syngas and benzene.
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子