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Enhanced stability of nitrogen-doped carbon-supported palladium catalyst for oxidative carbonylation of phenol

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Chinese Journal of Chemical Engineering 2024年第1期65卷 19-28页

作者： Xiaojing Liu Ruohan zhao Hao zhao Zhimiao w.ng Fang Li wei Xue Yanji w.ng Hebei Provincial Key Laboratory of Green Chemical Technology and High Efficient Energy Saving School of Chemical Engineering and TechnologyHebei University of TechnologyTianjin 300130China Tianjin Key Laboratory of Chemical Process Safety Tianjin 300130China Hebei Industrial Technology Research Institute of Green Chemical Industry Huanghua 061100China

Enhancing the stability of supported noble metal catalysts emerges is a major challenge in both science and ***,a heterogeneous Pd catalyst(Pd/nCF)was prepared by supporting Pd ultrafine metal nanoparticles(nPs)on nitrogen-doped carbon;synthesized by using F127 as a stabilizer,as well as chitosan as a carbon and nitrogen *** Pd/nCF catalyst was efficient and recyclable for oxidative carbonylation of phenol to diphenyl carbonate,exhibiting higher stability than Pd/nC prepared without F127 *** hydrogen bond between chitosan(CTS)and F127 was enhanced by F127,which anchored the n in the free amino group,increasing the n content of the carbon material and ensuring that the support could provide sufficient n sites for the deposition of Pd *** process helped to improve metal *** increased metal-support interaction,which limits the leaching and coarsening of Pd nPs,improves the stability of the Pd/nCF ***,density functional theory calculations indicated that pyridine n stabilized the Pd^(2+)species,significantly inhibiting the loss of Pd^(2+)in Pd/nCF during the reaction *** work provides a promising avenue towards enhancing the stability of nitrogen-doped carbon-supported metal catalysts.

关键词： Supported Pd catalyst n-doped carbon Amphiphilic triblock copolymer Pyridinic nitrogen Stability

Homological Transfer between Additive Categories and Higher Differential Additive Categories

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Acta Mathematica Sinica,English Series 2024年第5期40卷 1325-1344页

作者： Xi TAnG zhao Yong HUAnG School of Science Guilin University of Aerospace TechnologyGuilin 541004P.R.China Department of Mathematics Nanjing UniversityNanjing 210093P.R.China

Given an additive category C and an integer n≥*** higher differential additive category consists of objects X in C equipped with an endomorphism ϵ_(X)satisfying ϵ_(X)^(n).Let R be a,finite-dimensional basic algebra over an algebraically closed field and T the augmenting functor from the category of finitely generated left R-modules to that of finitely generated left R/(t^(n))-*** is proved that a finitely generated left R-module M isτ-rigid(respectively,(support)τ-tilting,almost completeτ-tilting)if and only if so is T(M)as a left R[t]/(t^(n))-***,R isτm-selfinjective if and only if so is R[t]/(t^(n)).

关键词： Higher differential objects wakamatsu tilting subcategories G_(ω)-projective modules sup-portτ-tilting modules τ_(m)-selfinjective algebras precluster tilting subcategories

Ionic liquid-assisted preparation of hydroxyapatite and its catalytic performance for decarboxylation of itaconic acid

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Chinese Journal of Chemical Engineering 2024年第3期67卷 9-15页

作者： Shutong Pang Hualiang An Xinqiang zhao Yanji w.ng Hebei Provincial Key Laboratory of Green Chemical Technology and Efficient Energy Saving Tianjin Key Laboratory of Chemical Process SafetySchool of Chemical Engineering and TechnologyHebei University of TechnologyTianjin 300130China

The synthesis of methacrylic acid from biomass-derived itaconic acid is a green route,for it can get rid of the dependence on fossil *** order to solve the problems on this route such as use of a preciousmetal catalyst and a corrosive homogeneous alkali,we prepared a series of hydroxyapatite catalysts by an ionic liquid-assisted hydrothermal method and evaluated their catalytic *** results showed that the ionic liquid[Bmim]BF_(4) can affect the crystal growth of hydroxyapatite,provide fluoride ion for fluorination of hydroxyapatite,and adjust the surface acidity and basicity,morphology,textural properties,crystallinity,and composition of ***[Bmim]BF4 dosage and hydrothermal temperature can affect the fluoride ion concentration in the hydrothermal system,thus changing the degree of fluoridation of *** fluoride-ion concentration can lead to the formation of CaF_(2) and thus significantly decrease the catalytic performance of *** hydrothermal time mainly affects the growth of hydroxyapatite crystals on the c axis,leading to different catalytic *** suitable conditions for the preparation of this fluoridized hydroxyapatite are as follows:a mass ratio of[Bmim]BF4 to calcium salt=0.2:1,a hydrothermal time of 12 h,and a hydrothermal temperature of 130℃.A maximal methacrylic acid yield of 54.7%was obtained using the fluoridized hydroxyapatite under relatively mild reaction conditions(250℃ and 2 MPa of n_(2))in the absence of a precious-metal catalyst and a corrosive homogeneous alkali.

关键词： Ionic liquid Hydroxyapatite Itaconic acid Methacrylic Decarboxylation reaction

Enhanced photocatalytic nitrogen fixation performance via in situ constructing BiO_(2-x)/nanbO_(3) heterojunction

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Chinese Journal of Chemical Engineering 2024年第5期69卷 92-100页

作者： Jiayu Zhang Zhihao Zeng Lin Yue Chunran zhao Xin Hu Leihong zhao Xiuw.n w.ng Yiming He Key Laboratory of the Ministry of Education for Advanced Catalysis Materials College of Chemistry and Materials ScienceZhejiang Normal UniversityJinhua 321004China Heilongjiang Provincial Key Laboratory of Surface Active Agent and Auxiliary School of Chemistry and Chemistry EngineeringQiqihar UniversityQiqihar 161006China Department of Materials Science and Engineering Zhejiang Normal UniversityJinhua 321004China

The fabrication of heterojunction catalysts is an effective strategy to enhance charge separation efficiency,thereby boosting the performance of *** this study,BiO_(2-x)nanosheets were synthesized through a hydrothermal process and loaded onto nanbO_(3) microcube to construct a series of BiO_(2-x)/nanbO_(3) heterojunctions for photocatalytic n_(2) *** indicated that 2.5%BiO_(2-x)/nanbO_(3) had the highest photocatalytic *** nH_(3) production rate under simulated solar light reached 406.4μmol·L^(-1)·g^(-1)·h^(-1),which reaches 2.6 and 3.8 times that of nanbO_(3) and BiO_(2-x),***_(2-x)nanosheets primarily act as electron trappers to enhance the separation efficiency of charge *** strong interaction between BiO_(2-x)and nanbO_(3) facilitates the electron migration between ***,the abundant oxygen vacancies in BiO_(2-x)nanosheets may facilitate the adsorption and activation of n_(2),which may be another possible reason of the high photocatalytic activity of the BiO_(2-x)/nanbO_(3).This study may offer new insights for the development of semiconductor materials in photocatalytic nitrogen fixation.

关键词： Catalyst Solar energy Hydrothermal BiO_(2-x)/nanbO_(3) Photocatalytic n_(2)-fixation

well-dispersed Sb particles embedded on n-doped carbon nanofibers toward high-performance Li-ion battery

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Rare Metals 2024年第7期43卷 2994-3006页

作者： Ying Li Yi-Han zhao Lu-Lu zhao Peng-Fei w.ng Ying Xie Ting-Feng Yi School of Materials Science and Engineering Northeastern UniversityShenyang 110819China Key Laboratory of Dielectric and Electrolyte Functional Material Hebei Province School of Resources and MaterialsNortheastern University at QinhuangdaoQinhuangdao 066004China Key Laboratory of Functional Inorganic Material Chemistry Ministry of EducationSchool of Chemistry and Materials ScienceHeilongjiang UniversityHarbin 150080China

The alloy-type material Sb is widely used in the anode materials of lithium-ion batteries(LIBs)due to its high theoretical specific ***,its serious volume expansion problem during alloying/dealloying of Li~+limits its practical *** this work,C-Sb composite was constructed as anode material of LIBs by electrospinning route for the first time,Sb was introduced into the polyacrylonitrile-based hard carbon and coal tar pitch-based soft carbon composite amorphous carbon fiber with a diameter of 300-600 nm,which realized high cycling *** C-Sb-2(the mass ratio of polyacrylonitrile to Sb source is 1:2)electrode displayed charge capacities of 1098.5,930.3,841.7,753.5,643.9 and 545.8 mAh·g^(-1)at 0.1,0.2,0.3,0.5,1 and 2 A·g^(-1),*** when the current density returned to 0.1 A·g^(-1),the charge capacity was 939.3 mAh·g^(-1),revealing good stability and *** introduction of Sb into the amorphous carbon improved its conductivity and addressed the volume expansion issue of high specific capacity Sb during charge/***-situ XRD analysis confirmed the high reversibility of the C-Sb-2 during charging and *** functional theory(DFT)calculations revealed the gradual enhancement of the interface interaction between Sb_(x)Li_(y) and amorphous carbon(AMC)with increasing lithium content,contributing to the anchoring of alloy nanoparticles on the AMC surface and buffering the volume change of the ***,the gradual lithiation of Sb facilitated the electron transfer from Sb_(x)Li_(y) to *** findings hold promise for designing lithium storage materials with exceptional performance,highlighting the potential of C-Sb composites as anode materials for efficient next-generation lithium storage.

关键词： Li-ion battery Metallic Sb Carbon Electrospinning Cycling stability

Efficient Direct Decomposition of nO over La_(0.8)A_(0.2)niO_(3)(A=K, Ba, Y) Catalysts under Microwave Irradiation

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Journal of wuhan University of Technology(Materials Science) 2024年第1期39卷 17-23页

作者：王浩 zhao Zijian DUAn Xinghui ZHOU Shijia School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China

La_(0.8)A_(0.2)niO_(3) (A=K,Ba,Y) catalysts supported on the microwave-absorbing ceramic heating carrier were prepared by the sol-gel *** crystalline phase and the catalytic activity of the La_(0.8)A_(0.2)niO_(3)catalysts were characterized by XRD and H_(2) temperature-programmed reduction (TPR).The effects of reaction temperature,oxygen concentration,and gas flow rate on the direct decomposition of nitric oxide over the synthesized catalysts were studied under microwave irradiation (2.45 GHz).The XRD results indicated that the La_(0.8)A_(0.2)niO_(3) catalysts formed an ABO_(3) perovskite structure,and the H_(2)-TPR results revealed that the relative reducibility of the catalysts increased in the order of La_(0.8)K_(0.2)niO_(3)>La_(0.8)Ba_(0.2)niO_(3)>La_(0.8)Y_(0.2)ni O_(3).Under microwave irradiation,the highest nO conversion amounted to 98.9%,which was obtained with the La_(0.8)K_(0.2)niO_(3) catalyst at 400℃.The oxygen concentration did not inhibit the nO decomposition on the La_(0.8)A_(0.2)niO_(3) catalysts,thus the n_(2) selectivity exceeded 99.8%under excess oxygen at 550℃.The nOconversion of the La_(0.8)A_(0.2)niO_(3) catalysts decreased linearly with the increase in the gas flow rate.

关键词： microwave catalysis direct decomposition of nO microwave-absorbing heating ceramics perovskite catalyst

Tuning interface mechanism of FeCo alloy embedded n,S-codoped carbon substrate for rechargeable Zn-air battery

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Journal of Energy Chemistry 2024年第6期93卷 400-410,I0010页

作者： Hui Chang Lulu zhao Shan zhao Zong-Lin Liu Peng-Fei w.ng Ying Xie Ting-Feng Yi School of Materials Science and Engineering Northeastern UniversityShenyang 110819LiaoningChina Key Laboratory of Functional Inorganic Material Chemistry Ministry of EducationSchool of Chemistry and Materials ScienceHeilongjiang UniversityHarbin 150080HeilongjiangChina Key Laboratory of Dielectric and Electrolyte Functional Material Hebei Province School of Resources and MaterialsNortheastern University at QinhuangdaoQinhuangdao 066004HebeiChina

The interface mechanism between catalyst and carbon substrate has been the focus of *** this paper,the FeCo alloy embedded n,S co-doped carbon substrate bifunctional catalyst(FeCo/S-nC)is obtained by a simple one-step pyrolysis *** experimental results and density functional theory(DFT)calculation show that the formation of FeCo alloy is conducive to promoting electron transfer,and the introduction of S atom can enhance the interaction between FeCo alloy and carbon substrate,thus inhibiting the migration and agglomeration of particles on the surface of carbon *** FeCo/SnC catalysts show outstanding performance for oxygen reduction reaction(ORR)and oxygen evolution reaction(OER).FeCo/S-nC shows a high half-wave potential(E_(1/2)=0.8823 V)for ORR and a low overpotential at 10 mA cm^(-2)(E_(j=10)=299 mV)for *** addition,compared with Pt/C+RuO_(2) assembled Zn-air battery(ZAB),the FeCo/S-nC assembled ZAB exhibits a larger power density(198.8 mw cm^(-2)),a higher specific capacity(786.1 mA h g_(zn)~(-1)),and ultra-stable cycle *** results confirm that the optimized composition and the interfacial interaction between catalyst and carbon substrate synergistically enhance the electrochemical performance.

关键词： FeCo alloy n S co-doped carbon DFT calculation Zn-air batteries Interfacial interaction

P-symmetric Subharmonic Solutions for nonlinear Hamiltonian Systems

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Acta Mathematica Sinica,English Series 2024年第6期40卷 1388-1408页

作者： Duan Zhi ZHAnG Zhi Hao zhao School of Mathematical Sciences Nankai UniversityTianjin 300071P.R.China

In this paper,we prove that for each positive k≡1 mod m there exists a P-symmetric kmτ-periodic solution xk for asymptotically linear mτ-periodic Hamiltonian systems,which are nonautonomous and endowed with a *** the P-symmetric Hamiltonian function is semi-positive,one can prove,under a new iteration inequality of the Maslov-type P-index,that xk_(1) and xk_(2) are geometrically distinct for k_(1)/k_(2)≥(2n+1)m+1;and xk_(1),xk_(2) are geometrically distinct for k_(1)/k_(2)≥m+1 provided xk_(1) is non-degenerate.

关键词： P-symmetric subharmonic Hamiltonian systems Maslov-type index theory iteration inequality asymptotically linear

Understanding the spatial interaction of ultrasounds based on three-dimensional dual-frequency ultrasonic field numerical simulation

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China Foundry 2024年第1期21卷 29-43页

作者： zhao-yang Yin Qi-chi Le Yan-chao Jiang Da-zhi zhao Qi-yu Liao Qi Zou Key Lab of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang 110819China School of Materials Science and Engineering Northeastern UniversityShenyang 110819China

A transient 3D model was established to investigate the effect of spatial interaction of ultrasounds on the dual-frequency ultrasonic field in magnesium alloy *** effects of insertion depth and tip shape of the ultrasonic rods,input pressures and their ratio on the acoustic field distribution were discussed in ***,the spacing,angle,and insertion depth of two ultrasonic rods significantly affect the interaction between distinct *** a result,various acoustic pressure distributions and cavitation regions are *** spherical rods mitigate the longitudinal and transversal attenuation of acoustic pressure and expand the cavitation volume by 53.7%and 31.7%,respectively,compared to the plate and conical *** the input pressure will enlarge the cavitation region but has no effect on the acoustic pressure distribution *** acoustic pressure ratio significantly affects the pressure distribution and the cavitation region,and the best cavitation effect is obtained at the ratio of 2:1(P15:P20).

关键词： dual-frequency ultrasonic numerical model acoustic pressure spatial interaction magnesium alloy