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Aminopyridine functionalized cellulose based Pd nanoparticles: An efficient and ecofriendly catalyst for the Suzukicross-coupling reaction

Peibo Hu,Yahao Dong,Xiaotian Wu,Yuping Wei

《化学科学与工程前沿（英文）》 2016年 第10卷 第3期   页码 389-395 doi: 10.1007/s11705-016-1575-1

摘要： A palladium catalyst supported on 2-aminopyridine functionalized cellulose was synthesized and fully characterized by inductively coupled plasma atomic emission spectroscopy, transmission electron microscope, Fourier transform infrared spectroscopy, thermogravimetric analysis and X-ray photoelectron spectrometry. This catalyst can be applied in the Suzuki cross-coupling reaction of aryl halides with arylboronic acids in 50% ethanol to afford biaryls in?good yields, and easily recycled by simple filtration after reaction without the loss of metal Pd.

关键词： cellulose-supported     2-aminopyridine     palladium nanoparticles     ecofriendly catalyst     Suzuki cross-coupling reaction    

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Pd/Fe3O4 supported on bio-waste derived cellulosic-carbon as a nanocatalyst for C–C coupling and electrocatalytic

《化学科学与工程前沿（英文）》 2022年 第16卷 第10期   页码 1514-1525 doi: 10.1007/s11705-022-2158-y

摘要： The current work describes the synthesis of a new bio-waste derived cellulosic-carbon supported-palladium nanoparticles enriched magnetic nanocatalyst (Pd/Fe3O4@C) using a simple multi-step process under aerobic conditions. Under mild reaction conditions, the Pd/Fe3O4@C magnetic nanocatalyst demonstrated excellent catalytic activity in the Hiyama cross-coupling reaction for a variety of substrates. Also, the Pd/Fe3O4@C magnetic nanocatalyst exhibited excellent catalytic activity up to five recycles without significant catalytic activity loss in the Hiyama cross-coupling reaction. Also, we explored the use of Pd/Fe3O4@C magnetic nanocatalyst as an electrocatalyst for hydrogen evolution reaction. Interestingly, the Pd/Fe3O4@C magnetic nanocatalyst exhibited better electrochemical activity compared to bare carbon and magnetite (Fe3O4 nanoparticles) with an overpotential of 293 mV at a current density of 10 mA·cm–2.

关键词： bio-waste     cellulosic-carbon     Pd/Fe3O4     Hiyama cross-coupling     hydrogen evolution reaction     recyclability    

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Pd-Ni nanoparticles supported on titanium oxide as effective catalysts for Suzuki-Miyaura coupling reactions

Dongxu Han, Zhiguo Zhang, Zongbi Bao, Huabin Xing, Qilong Ren

《化学科学与工程前沿（英文）》 2018年 第12卷 第1期   页码 24-31 doi: 10.1007/s11705-017-1669-4

摘要： We have successfully prepared a series of Pd-Ni/TiO catalysts by a one-step impregnation-reduction method. Among these catalysts with different compositions of Ni and Pd, the one with the Ni:Pd ratio of 2.95 showed the best activity. Small monodispersed Pd-Ni bimetallic nanoparticles were loaded on the surface of titanium oxide nanopowder as confirmed with TEM and EDS mapping. The XPS analysis demonstrated that Pd exists as 31% Pd(II) species and 69% Pd(0) species and all nickel is Ni(II). The prepared Pd-Ni/TiO exhibited enhanced catalytic activity compared to an equal amount of Pd/TiO for Suzuki-Miyaura reactions together with excellent applicability and reusability.

关键词： Pd-Ni bimetallic nanoparticles     nanocatalysis     Suzuki-Miyaura reaction     titanium oxide    

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Mild and highly regioselective synthesis of biaryl acids via Rh(I)-catalyzed cross-dehydrogenative coupling

Yun Liu, Youquan Zhu, Chaojun Li

《化学科学与工程前沿（英文）》 2018年 第12卷 第1期   页码 3-8 doi: 10.1007/s11705-017-1693-4

摘要： A mild and efficient synthesis for the biaryl acids via rhodium-catalyzed cross-dehydrogenative coupling reaction has been developed. This novel protocol with sodium chlorite as an oxidant featured many advantages such as mild reaction conditions, high regioselectivity, tolerance of various functional groups, and good to excellent yields.

关键词： biaryl acids     cross-dehydrogenative coupling     rhodium-catalyzed    

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Simultaneous removal of trihalomethanes by bimetallic Ag/Zn: kinetics study

Ahmed H A DABWAN, Satoshi KANECO, Hideyuki KATSUMATA, Kiyoyuki EGUSA, Tohru SUZUKI, Kiyohisa OHTA,

《化学科学与工程前沿（英文）》 2010年 第4卷 第3期   页码 322-327 doi: 10.1007/s11705-009-0261-y

摘要： In the present work, bimetallic silver/zinc was applied into the degradation of trihalomethanes, THMs: CHCl, CHBrCl, CHBrCl, and CHBr. The kinetics reaction rates and removal efficiencies of the THM compound mixtures, in the aqueous solutions, were investigated. Batch experiments were conducted under mild conditions, ambient temperature, and pressure. The primary degradation reaction followed a pseudo-first-order kinetic law. The first-order rate constants and the degradation efficiencies followed the decreasing order of CHBr>CHBrCl>CHBrCl>CHCl. The bond dissociation energy and hydrophilic/hydrophobic characteristics of the THM compounds may become the most important parameters affecting the degradation kinetics and efficiency by bimetallic Ag/Zn.

关键词： reaction     first-order     dissociation     degradation reaction     aqueous    

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Effect of alkyl nitrite decomposition on catalytic performance of CO coupling reaction over supported

Zhenhua LI, Weihan WANG, Dongxue YIN, Jing LV, Xinbin MA

《化学科学与工程前沿（英文）》 2012年 第6卷 第4期   页码 410-414 doi: 10.1007/s11705-012-1213-5

摘要： The syntheses of dimethyl oxalate (DMO) and diethyl oxalate (DEO) by CO coupling reaction in gaseous phase were investigated in a fixed bed reactor over Pd-Fe/Al O catalyst. The catalytic performance was characterized by CO conversion, space-time yield (STY) and selectivity of DMO (or DEO). The results showed that over Pd-Fe/Al O catalyst, the STY of DMO was higher than that of DEO under the same reaction conditions. The optimum reaction temperatures for synthesizing DMO and DEO were 403 K and 393 K, respectively, at the molar ratio 1 ∶ 1 of alkyl nitrite to CO. The difference in synthesizing DMO and DEO on the same catalyst was attributed to the decomposition performances of methyl nitrite (MN) and ethyl nitrite (EN), as density functional theory (DFT) calculation showed that EN decomposed more easily than MN.

关键词： palladium     CO coupling     dialkyl oxalate     alkyl nitrite     decomposition    

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Enhancing the aromatic selectivity of cyclohexane aromatization by CO2 coupling

《化学科学与工程前沿（英文）》 2023年 第17卷 第11期   页码 1801-1808 doi: 10.1007/s11705-023-2325-9

摘要： Improving the aromatic selectivity in the alkane aromatization process is of great importance for its practical utilization but challenge to make because the high H/C ratio of alkanes would lead to a serious hydrogen transfer process and a large amount of light alkanes. Herein, CO2 is introduced into the cyclohexane conversion process on the HZSM-5 zeolite, which can improve the aromatic selectivity. By optimizing the reaction conditions, an improved aromatic (benzene, toluene, xylene, and C9+) selectivity of 48.2% can be obtained at the conditions of 2.7 MPa (CO2), 450 °C, and 1.7 h−1, which is better than that without CO2 (aromatic selectivity = 43.2%). In situ transmission Fourier transform infrared spectroscopy spectra illustrate that many oxygenated chemical intermediates (e.g., carboxylic acid, anhydride, unsaturated aldehydes/ketones or ketene) would be formed during the cyclohexane conversion process in the presence of CO2. 13C isotope labeling experimental results demonstrate that CO2 can enter into the aromatics through the formation of oxygenated chemical intermediates and thereby improve the aromatic selectivity. This study may open a green, economic, and promising way to improve the aromatic selectivity for alkane aromatization process.

关键词： aromatics     carbon dioxide     aromatization     coupling reaction     ZSM-5 zeolite    

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Numerical modeling of mass transfer processes coupling with reaction for the design of the ozone oxidation

Hong Li, Fang Yi, Xingang Li, Xin Gao

《化学科学与工程前沿（英文）》 2021年 第15卷 第3期   页码 602-614 doi: 10.1007/s11705-020-1963-4

摘要： A computational model for an ozone oxidation column reactor used in dyeing wastewater treatment is proposed to represent, simulate, and predict the ozone bubble process. Considering the hydrodynamics, mass transfer, and ozone oxidation reaction, coupling modeling can more realistically calculate the ozone oxidation bubble process than the splitting methods proposed in previous research. The modeling is validated and shows great consistency with experimental data. The verified model is used to analyze the effect of operating conditions, such as the initial gas velocity and the ozone concentration, and structural conditions, such as multiple gas inlets. The ozone consumption is influenced by the gas velocity and the initial ozone concentration. The ozone’s utilization decreases with the increasing gas velocity while nearly the same at different initial ozone concentrations. Simulation results can be used in guiding the practical operation of dyeing wastewater treatment and in other ozonation systems with known rate constants in wastewater treatment.

关键词： ozone     wastewater treatment     numerical simulation     mass transfer    

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Rosin side chain type catalyst-free vitrimers with high cross-link density, mechanical strength, and

《化学科学与工程前沿（英文）》 2023年 第17卷 第9期   页码 1267-1279 doi: 10.1007/s11705-022-2291-7

摘要： The emergence of vitrimer, a new class of polymer materials can address the problem of recyclability, reprocess ability and recyclability of thermosetting plastics. Rosin, a natural product, is an ideal raw material for the preparation of polymers in a more sustainable way. Nevertheless, due to the huge steric hindrance caused by the hydrogenated phenanthrene ring structure, the cross-link density of materials is frequently lowered. In this study, hydrogenated rosin was adopted for preparing hydrogenated rosin side-chain type diacids, which were reacted with mixed epoxy to obtain rosin side-chain type vitrimers. It was completely characterized by differential scanning calorimetry test, thermogravimetric analysis, shape memory test and self-healing test. The prepared vitrimers exhibited good self-healing properties, excellent heat resistance (Td = 352 °C) as well as high mechanical properties (tensile strength of 46.75 MPa). The tricyclic diterpene structure of rosin was introduced into the side chain in order to avoid the reduction of cross-link density resulting from the huge steric hindrance of the rigid tricyclic hydrophenylene skeleton. Vitrimers can undergo dynamic transesterification reaction without external catalysts due to the autocatalytic effect of tertiary amines from epoxy. Moreover, our work expanded the application field of rosin, increased the added value of rosin, and provided a novel method for preparing rosin-based vitrimers with ideal properties.

关键词： vitrimers     rosin     catalyst-free     high mechanical properties     dynamic transesterification reaction    

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Chord error constraint based integrated control strategy for contour error compensation

Tie ZHANG, Caicheng WU, Yanbiao ZOU

《机械工程前沿（英文）》 2020年 第15卷 第4期   页码 645-658 doi: 10.1007/s11465-020-0601-7

摘要： As the traditional cross-coupling control method cannot meet the requirements for tracking accuracy and contour control accuracy in large curvature positions, an integrated control strategy of cross-coupling contour error compensation based on chord error constraint, which consists of a cross-coupling controller and an improved position error compensator, is proposed. To reduce the contour error, a PI-type cross-coupling controller is designed, with its stability being analyzed by using the contour error transfer function. Moreover, a feed rate regulator based on the chord error constraint is proposed, which performs speed planning with the maximum feed rate allowed by the large curvature position as the constraint condition, so as to meet the requirements of large curvature positions for the chord error. Besides, an improved position error compensation method is further presented by combining the feed rate regulator with the position error compensator, which improves the tracking accuracy via the advance compensation of tracking error. The biaxial experimental results of non-uniform rational B-splines curves indicate that the proposed integrated control strategy can significantly improve the tracking and contour control accuracy in biaxial contour following tasks.

关键词： cross-coupling controller     contour error     tracking error     position error compensator     feed rate regulator    

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Reaction and characterization of crosslinking hyperbranched poly (amine-ester) with succine anhydride

XIAO Ling, WEI Xiuzhen, ZHU Baoku

《化学科学与工程前沿（英文）》 2007年 第1卷 第4期   页码 355-359 doi: 10.1007/s11705-007-0064-y

摘要： Basing on hydroxyl terminated hyperbranched poly (amine-ester)s (HPAEs), the cross-linking reactions and preparation of ester-crosslinked HPAE films were investigated using succine anhydride (SA) as crosslink reagent. It was proved that the cross-linking reaction between HPAE and SA followed a two-step mechanism. This mechanism provides an efficient route to prepare HPAE/SA cross-linked films, in which, the precursor films were prepared by casting HPAE/SA solution at a lower temperature, and then curing the films at a higher temperature. By varying SA content, the solid HPAE/SA films with different cross-linking degrees were prepared successfully. The highest tensile strength of the cross-linked film could reach 59.60 MPa. With all water contact angle smaller than 74.3°, the crosslinked films demonstrated good hydrophilic properties.

关键词： different cross-linking     amine-ester     temperature     crosslinked     efficient    

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Development of highly active coated monolith SCR catalyst with strong abrasion resistance for low-temperature application

Lina GAN,Shan LEI,Jian YU,Hongtao MA,Yo YAMAMOTO,Yoshizo SUZUKI,Guangwen XU,Zhanguo ZHANG

《环境科学与工程前沿（英文）》 2015年 第9卷 第6期   页码 979-987 doi: 10.1007/s11783-015-0824-8

摘要： Monolith SCR catalysts coated with V O -WO /TiO were prepared by varying binder and coating thickness. Comparing with a monolith extruded with 100% V O -WO /TiO powder, a coated monolith with a catalyst-coating layer of 260 μm in thickness exhibited the similar initial NO reduction activity at 250°C. After 4 h abrasion (attrition) in an air stream containing 300 g·m fine sands (50–100 μm) at a superficial gas velocity of 10 m·s , the catalyst still has the activity as a 100% molded monolith does in a 24-h activity test and it retains about 92% of its initial activity at 250°C. Estimation of the equivalent durable hours at a fly ash concentration of 1.0 g·m in flue gas and a gas velocity of 5 m·s demonstrated that this coated monolith catalyst is capable of resisting abrasion for 13 months without losing more than 8% of its initial activity. The result suggests the great potential of the coated monolith for application to de-NO of flue gases with low fly ash concentrations from, such as glass and ceramics manufacturing processes.

关键词： coated monolith     low-temperature denitration     abrasion resistance     attrition    

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Evaluation method of dam behavior during construction and reservoir filling and application to real dams

Yuji KOHGO, Akira TAKAHASHI, Tomokazu SUZUKI,

《结构与土木工程前沿（英文）》 2010年 第4卷 第1期   页码 92-101 doi: 10.1007/s11709-010-0009-2

摘要： In this paper we analyzed a real fill-type dam, named the Minami-Aiki Dam, to verify a numerical consolidation method with an elastoplastic model for unsaturated soils. The validities were conducted by comparing the analyzed and measured values during construction and impounding. The settlements calculated showed good agreement to those observed. Though the changing patterns of the measured and calculated pore water pressures were similar, the amounts of pore water pressures induced by the self-weights of embankment and the dissipation speeds were different. The earth pressures measured at the bottom of the core zone showed good agreement with those calculated. This method is valid for estimating behavior of fill-type dams during construction and impounding.

关键词： fill dam     consolidation analysis     unsaturated geo-materials     impounding     construction    

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Enhanced hydrogen production from aqueous methanol solution using TiO

Paramasivan GOMATHISANKAR,Tomoko NODA,Hideyuki KATSUMATA,Tohru SUZUKI,Satoshi KANECO

《化学科学与工程前沿（英文）》 2014年 第8卷 第2期   页码 197-202 doi: 10.1007/s11705-014-1417-y

摘要： The photocatalytic hydrogen production from aqueous methanol solution using titanium dioxide (TiO ) was investigated in the addition of metal particles including copper, lead, tin, and zinc. The results show that only the addition of copper particles enhances the hydrogen production. The copper usage and reaction temperature were further optimized for TiO /Cu photocatalyts. Under the optimal conditions, the hydrogen production using TiO /Cu as photocatalysts is approximately 68 times higher than that obtained with only TiO .

关键词： photocatalytic hydrogen generation     methanol     copper particles     TiO2     metal-semiconductor interface    

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Microdamage study of granite under thermomechanical coupling based on the particle flow code

《结构与土木工程前沿（英文）》   页码 1413-1427 doi: 10.1007/s11709-023-0953-2

摘要： The thermomechanical coupling of rocks refers to the interaction between the mechanical and thermodynamic behaviors of rocks induced by temperature changes. The study of this coupling interaction is essential for understanding the mechanical and thermodynamic properties of the surrounding rocks in underground engineering. In this study, an improved temperature-dependent linear parallel bond model is introduced under the framework of a particle flow simulation. A series of numerical thermomechanical coupling tests are then conducted to calibrate the micro-parameters of the proposed model by considering the mechanical behavior of the rock under different thermomechanical loadings. Good agreement between the numerical results and experimental data are obtained, particularly in terms of the compression, tension, and elastic responses of granite. With this improved model, the thermodynamic response and underlying cracking behavior of a deep-buried tunnel under different thermal loading conditions are investigated and discussed in detail.

关键词： thermomechanical coupling effect     granite     improved linear parallel bond model     thermal property     particle flow code    

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标题 作者 时间 类型 操作

Aminopyridine functionalized cellulose based Pd nanoparticles: An efficient and ecofriendly catalyst for the Suzukicross-coupling reaction

Peibo Hu,Yahao Dong,Xiaotian Wu,Yuping Wei

期刊论文

Pd/Fe3O4 supported on bio-waste derived cellulosic-carbon as a nanocatalyst for C–C coupling and electrocatalytic

期刊论文

Pd-Ni nanoparticles supported on titanium oxide as effective catalysts for Suzuki-Miyaura coupling reactions

Dongxu Han, Zhiguo Zhang, Zongbi Bao, Huabin Xing, Qilong Ren

期刊论文

Mild and highly regioselective synthesis of biaryl acids via Rh(I)-catalyzed cross-dehydrogenative coupling

Yun Liu, Youquan Zhu, Chaojun Li

期刊论文

Simultaneous removal of trihalomethanes by bimetallic Ag/Zn: kinetics study

Ahmed H A DABWAN, Satoshi KANECO, Hideyuki KATSUMATA, Kiyoyuki EGUSA, Tohru SUZUKI, Kiyohisa OHTA,

期刊论文

Effect of alkyl nitrite decomposition on catalytic performance of CO coupling reaction over supported

Zhenhua LI, Weihan WANG, Dongxue YIN, Jing LV, Xinbin MA

期刊论文

Enhancing the aromatic selectivity of cyclohexane aromatization by CO2 coupling

期刊论文

Numerical modeling of mass transfer processes coupling with reaction for the design of the ozone oxidation

Hong Li, Fang Yi, Xingang Li, Xin Gao

期刊论文

Rosin side chain type catalyst-free vitrimers with high cross-link density, mechanical strength, and

期刊论文

Chord error constraint based integrated control strategy for contour error compensation

Tie ZHANG, Caicheng WU, Yanbiao ZOU

期刊论文

Reaction and characterization of crosslinking hyperbranched poly (amine-ester) with succine anhydride

XIAO Ling, WEI Xiuzhen, ZHU Baoku

期刊论文

Development of highly active coated monolith SCR catalyst with strong abrasion resistance for low-temperature application

Lina GAN,Shan LEI,Jian YU,Hongtao MA,Yo YAMAMOTO,Yoshizo SUZUKI,Guangwen XU,Zhanguo ZHANG

期刊论文

Evaluation method of dam behavior during construction and reservoir filling and application to real dams

Yuji KOHGO, Akira TAKAHASHI, Tomokazu SUZUKI,

期刊论文

Enhanced hydrogen production from aqueous methanol solution using TiO

Paramasivan GOMATHISANKAR,Tomoko NODA,Hideyuki KATSUMATA,Tohru SUZUKI,Satoshi KANECO

期刊论文

Microdamage study of granite under thermomechanical coupling based on the particle flow code

期刊论文