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Chinese Chemical Letters 2006年第8期17卷 1025-1028页

作者： Dong Sen MAO guan zhong lu Research Institute Applied Catalysis Department of Chemical Engineering Shanghai Institute of Technology Shanghai 200235

The addition of platinum over the B2O3/TiO2-ZrO2 remarkably enhanced its catalytic stability in the vapor phase Beckmann rearrangement of cyclohexanone oxime under the carder gas of H2. The content of coke deposited on catalyst surface was decreased from 1.92% over the B2O3/TiO2-ZrO2 to 1.14% over the platinum promoted B2O3/TiO2-ZrO2 after reaction of six hours. This result indicates that the platinum added on the B2O3/TiO2-ZrO2 catalyst plays an important role in reducing the coke formation on the catalyst surface.

关键词： Cyclohexanone oxime vapor-phase Beckmann rearrangement ε-caprolactam B2O3/TiO2-ZrO2 catalyst platinum.

Poly(GMA/MA/MBAA)Copolymer Beads:a Highly Efficient Support Immobilizing Penicillin G Acylase

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Chinese Chemical Letters 2006年第1期17卷 129-132页

作者： Ping XUE guan zhong lu Wan Yi LIU Key Laboratory of Energy Source and Chemical Engineering Ningxia University Yinchuan 750021 Research Institute of Industrial Catalysis East China University of Science and Technology Shanghai 200237

The hydrophilic, macroporous and beaded ternary copolymer of glycidyl methacrylate （GMA）/methacrylamide（MA）/N,N＇-methylene-bis（acrylamide）（MBAA）was synthesized using the industrial agents by inverse suspension polymerization. The apparent activity of the immobilized penicillin G acylase reached 1096 IU/g for hydrolysis penicillin G on the beads with diameter of 0.11-0.13 ram, and it changed hardly after 50 cycles. It can be expected to be a good potential in industrial application,

关键词： Poly(GMA/MA/MBAA) copolymer beads penicillin G acylase immobilization,inverse suspension polymerization.

Tuning performance of Pd/Sn_(0.9)Ce_(0.1)O_2 catalyst for methane combustion by optimizing calcination temperature of support

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Rare Metals 2019年第2期38卷 107-114页

作者： Kai Shen Jia-Pan Lin Qian Xia lu Dai Guo-Jun Zhou Yang-Long Guo guan-zhong lu Wang-Cheng Zhan Technology Center China Tobacco Zhejiang Industrial Co.Ltd. Key Laboratory for Advanced Materials and Research Institute of Industrial Catalysis East China University of Science and Technology

A series of 0.2 wt% Pd/Sn_(0.9)Ce_(0.1)O_2 catalysts were prepared by impregnation method based on the presynthesis of Sn_(0.9)Ce_(0.1)O_2 support prepared by co-precipitation method, and then characterized by Brunauer–Emmett–Teller(BET), X-ray diffraction(XRD), X-ray photoelectron spectroscopy(XPS), Raman, CO chemical adsorption and hydrogen temperature-programmed reduction(H_2-TPR) techniques. The effect of calcination temperature of the composite oxide support on the catalytic performances of the Pd/Sn_(0.9)Ce_(0.1)O_2 catalyst for the CH_4 total oxidation was studied. It is found that the catalytic activity of the Pd/Sn_(0.9)Ce_(0.1)O_2 catalyst increases with the increase in calcination temperature of the Pd/Sn_(0.9)Ce_(0.1)O_2 support. The 0.2 wt% Pd/Sn_(0.9)Ce_(0.1)O_2/1100 catalyst(the Pd/Sn_(0.9)Ce_(0.1)O_2 support was calcined at 1100 ℃) exhibits the best reactive activity(T_(10)= 255 ℃). The excellent activity of the 0.2 wt% Pd/Sn_(0.9)Ce_(0.1)O_2/1100 catalyst should be attributed to the high reducibility of PdO, the excellent oxygen mobility of the support and the high content of active Pd^(2+) species on the Pd/Sn_(0.9)Ce_(0.1)O_2 catalyst.

关键词： Catalytic combustion Methane PdO SnxCe1-xO2 Calcination temperature

Epoxidation of propylene by molecular oxygen over unsupported AgCu_x bimetallic catalyst

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Rare Metals 2015年第7期34卷 477-490页

作者： Xiang Zheng Yang-Long Guo Yun Guo Qing Zhang Xiao-Hui Liu Li Wang Wang-Cheng Zhan guan-zhong lu Key Laboratory for Advanced Materials Research Institute of Industrial Catalysis East China University of Science and Technology

The unsupported Cu and Ag catalysts with different oxidation states were prepared, and their catalytic performances for propylene epoxidation were *** metallic Cu catalyst exhibits much higher catalytic activity and propylene oxide(PO) selectivity than Cu2 O and Cu O *** Cu0 species are the main active sites for propylene epoxidation, but Cu2 O and Cu O species are in favor of CO2 and acrolein *** PO selectivity of 54.2 % and propylene conversion of 2.6 % can be achieved over the metallic Cu catalyst at 160 °C in initial stage, but metallic Cu catalyst would be oxidized to Cu2 O during propylene epoxidation, resulting in a sharp decrease in the PO selectivity and propylene *** Ag Cuxbimetallic catalysts were *** is found that adding Ag to the metallic Cu catalysts can prevent the oxidation of Cu and make Ag Cuxbimetallic catalysts more stable under the condition of propylene *** Ag/Cu molar ratio can remarkably affect the catalytic performance of Ag Cuxcatalyst and the selectivity to PO and *** Ag Cuxwas supported on MOx-modified a-Al2O3, its catalytic performance can be improved and has a close relationship with the acid–base property of support.

关键词： Epoxidation of propylene Propylene oxide Molecular

Thermal stability of Si-doped V2O5/WO3-TiO2 for selective catalytic reduction of NOx by NH3

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Rare Metals 2019年第4期38卷 292-298页

作者： Xun-Zhe Shao Hong-You Wang Meng-Long Yuan Jie Yang Wang-Cheng Zhan Li Wang Yun Guo guan-zhong lu Laboratory for Research Institute of Industrial Catalysis School of Chemistry and Molecular Engineering East China University of Science and Technology

The selective catalytic reduction of NOV with NH3 (NH3-SCR) is a very effective technology to control the emission of NOA, and the thermal stability of NH3-SCR catalyst is very important for removal of NOV from diesel engines. In this work, V2O5/WO3-TiO2 (VWT) and SiO2- doped V2O5/WO3-TiO2 (VWTSi10)) catalysts were prepared by impregnation method and characterized by Brunauer- Emmett-Teller (BET), X-ray diffraction (XRD), Raman, temperature programmed reduction by hydrogen (H2-TPR), X-ray photoelectron spectroscopy (XPS) and temperature programmed desorption by ammonia (NH3- TPD). The doping of SiO2 promotes the thermal stability of V2O5/WO3-TiO? for NH3-SCR significantly. After calcination at 650 °C for 50 h, the operation window of 10% SiO2-doped V2O5/WO3-TiO2 is 220-480 °C, while the maximum NOV conversion on V2O5/WO3-TiO2 is about 77%. The presenee of SiO2 obviously blocks the transformation of TiO2 from anatase to rutile and stabilizes the dispersion of VOv and WO3 on the surface. It is available for the existence of V44 and the amount of surface acid sites increases, which inhabits the NH3 oxidation at the high temperature range and promotes NH3-SCR activity.

关键词： V2O5/WO3-TiO2 SiO2 NH3-SCR Thermal stability

Catalytic activity of Cu-SSZ-13 prepared with different methods for NH_3-SCR reaction

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Rare Metals 2019年第3期38卷 210-220页

作者： Meng-Jie Han Yun-Lei Jiao Chun-Hong Zhou Yang-Long Guo Yun Guo guan-zhong lu Li Wang Wang-Cheng Zhan Key Laboratory for Advanced Materials and Research Institute of Industrial Catalysis East China University of Science and Technology

A series of Cu-SSZ-13 catalysts with the same Cu loading were prepared by different methods of incipient wetness impregnation [Cu-SSZ-13(IWI)], ion exchange[Cu-SSZ-13(IE)] and hydro-thermal synthesis [Cu-SSZ-13(HTS)]. Their activity for selective catalytic reduction of nitrogen oxides(NO_x) with NH3 was determined. The results show that the Cu-SSZ-13(HTS) catalyst exhibits a better ammonia selective catalytic reduction(NH3-SCR)activity compared with the other two catalysts, over which more than 90% NO conversion is obtained at 215-600℃under the space velocity of 180,000 h^(-1). The characterization results reveal that the Cu-SSZ-13(HTS) catalyst possesses more amount of stable Cu^(2+) in the six-membered ring and high ability for NH3 and NO adsorption, leading to its high NH3-SCR activity, although this catalyst has low surface area. On the other hand, the activity of Cu-SSZ-13(IE) catalyst is almost the same as that of Cu-SSZ-13(IWI) catalyst at the temperature lower than 400 ℃, but the activity of the former is much higher than that of the latter at > 400 ℃ due to the high activity of Cu-SSZ-13(IWI) catalyst for NH3 oxidation.

关键词： SSZ-13 zeolite Selective catalytic reduction Nitrogen oxides Preparation method Cu2+

Analysis of photocatalytic degradation of polyamide microplastics in metal salt solution by high resolution mass spectrometry

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Journal of Environmental Sciences 2024年第5期139卷 473-482页

作者： Yunjin zhong Lebing Zhuo Wangyang lu National Engineering Lab for Textile Fiber Materials&Processing Technology(Zhejiang) School of Materials Science&EngineeringZhejiang Sci-Tech UniversityHangzhou 310018China

Microplastic pollution has become one of the most concerned focuses in the *** many treatment methods,photocatalysis is considered to be one of the most environmentally friendly *** this work,the photodegradation behavior of polyamide microplastics is studied by using polyamide 6(PA6)as model microplastics and FeCl_(3) as *** is hoped that the PA6 fiber can be effectively degraded by utilizing the strong oxidizing active species that can be produced after FeCl_(3) is irradiated in *** results shows that PA6 fiber can be almost completely degraded after 10 days of irradiation in FeCl_(3) aqueous solution,indicating that it is promising to use this new method to solve the problem of PA6type *** addition,the chain scission mechanism and degradation process of PA6 are analyzed in detail by ultra-high performance liquid chromatography-tandem mass spectrometry(UPLC-MS),which provides a new insight for the study of polymer degradation mechanism.

关键词： FeCl_(3) Photocatalysis Polyamide 6 Chain scission

Combined UAMP and MF Message Passing Algorithm for Multi-Target Wideband DOA Estimation with Dirichlet Process Prior

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Tsinghua Science and Technology 2024年第4期29卷 1069-1081页

作者： Shanwen guan Xinhua lu Ji Li Rushi Lan Xiaonan luo guangxi Key Laboratory of Image and Graphic Intelligent Processing Guilin University of Electronic TechnologyGuilin 541004China Guilin Huigu Institute of AI Industrial Technology Guilin 541004China School of Information Engineering Nanyang Institute of TechnologyNanyang 473000China

When estimating the direction of arrival (DOA) of wideband signals from multiple sources, the performance of sparse Bayesian methods is influenced by the frequency bands occupied by signals in different directions. This is particularly true when multiple signal frequency bands overlap. Message passing algorithms (MPA) with Dirichlet process (DP) prior can be employed in a sparse Bayesian learning (SBL) framework with high precision. However, existing methods suffer from either high complexity or low precision. To address this, we propose a low-complexity DOA estimation algorithm based on a factor graph. This approach introduces two strong constraints via a stretching transformation of the factor graph. The first constraint separates the observation from the DP prior, enabling the application of the unitary approximate message passing (UAMP) algorithm for simplified inference and mitigation of divergence issues. The second constraint compensates for the deviation in estimation angle caused by the grid mismatch problem. Compared to state-of-the-art algorithms, our proposed method offers higher estimation accuracy and lower complexity.

关键词： wideband direction of arrival(DOA)estimation sparse Bayesian learning(SBL) unitary approximate message passing(UAMP)algorithm Dirichlet process(DP)

Exploring a balance between strength and ductility of hexagonal BN nanoplatelet reinforced ZK61 magnesium composite

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Journal of Magnesium and Alloys 2024年第5期12卷 1899-1910页

作者： Kewei Zhang Xiaolong lu Yufeng Sun Shaokang guan Yao Chen School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China Key Laboratory of Advanced Magnesium Alloys in Henan Province Zhengzhou UniversityZhengzhou 450002China Key Laboratory of Advanced Materials Processing&Mold Ministry of EducationZhengzhou 450002China School of Mechanical and Electrical Engineering Soochow UniversitySuzhou 215021China

The practical applications of magnesium(Mg)alloys are usually beset by their relatively low strength and limited *** we attempt to fabricate hexagonal BN nanoplatelet(BNNP)reinforced ZK61 magnesium composites using a combination of spark plasma sintering and friction stir *** resulting composites exhibit microstructural characteristics of homogeneous dispersion of BNNP in Mg matrix with refined equiaxed grains and(0002)basal texture roughly surrounding the pin column *** electron microscopy observation illustrates that trace amounts of Mg_(3)N_(2)and MgB_(2)form at BNNP-Mg interface,in which Mg_(3)N_(2)locates at the basal plane of a BNNP and MgB_(2)grows at its open *** spatial distribution of Mg_(3)N_(2)and MgB_(2)facilitates interfacial wetting and stronger BNNP-Mg interface in such a way that interfacial products act as anchors bonding between *** comparison with monolithic ZK61 alloy,the BNNP/ZK61 composites display simultaneous improvements in yield strength,hardness and ductility,achieving good strength-ductility *** research is expected to shed some light on BNNP potentials for designing and producing magnesium composites with high strength and good ductility.

关键词： BN nanoplatelet Magnesium composite Strength Ductility Spark plasma sintering Friction stir processing

Grating-free autofocus for single-pixel microscopic imaging

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Photonics Research 2024年第6期12卷 1313-1321页

作者： guan WANG HUAXIA DENG YU CAI MENGCHAO MA XIANG zhong XINGLONG GONG CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Modern MechanicsUniversity of Science and Technology of ChinaHefei 230027China School of Instrument Science and Opto-electronics Engineering Hefei University of TechnologyHefei 230009China

As a computational technology,single-pixel microscopic imaging(SPMI)transfers the target’s spatial information into a temporal *** traditional focusing method of imaging before evaluation is not applicable to the SPMI *** propose a grating-free autofocus strategy derived from the physical mechanism of optical *** the amplitude information of just one high-frequency point in the spectrum is all that is needed to achieve fast autofocus with the SPMI ***,only four patterns need to be cyclically projected,enabling efficient localization of the focal plane based on the measurement *** demonstrate SPMI autofocus experiments at micrometer and even nanometer depths of *** proposed method can be extended to achieve SMPI autofocus with invisible optical pattern illumination.

关键词： optical system illumination