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Journal of Natural Gas Chemistry 2012年第1期21卷 1-6页

作者： rongjun zhang Dehua He Innovative Catalysis Program Key Lab of Organic Optoelectronics and Molecular EngineeringDepartment of ChemistryTsinghua UniversityBeijing 100084China

A series of ZrO2 catalysts were prepared by treating ZrO（OH）2 hydrogel with different alcohol solvents （C2-C4 alcohols） and calcining under N2 flow at 773 K for 3 h. The obtained ZrO2 catalysts were systematically characterized by the methods of N2 adsorption-desorption, powder X-ray diffraction, NH3 temperature-programmed desorption, and CO2 temperature-programmed desorption. The catalytic performance of each catalyst was evaluated in the selective synthesis of iso-C4 （isobutene and isobutane） and light olefins （C2-C4） from CO hydrogenation. The specific surface area increased for the ZrO2 catalysts obtained by treating ZrO（OH）2 hydrogel with different alcohol solvents. The amounts of both acidic and basic sites on the catalyst surface increased obviously. The catalytic activity （CO conversion） of ZrO2 catalysts also increased after the treatment with different alcohol solvents. The nighest activity was obtained over the catalyst which was pretreated with isopropanol. However, alcohol solvent treatment retarded the transformation of ZrO2 crystal structure from tetragonal phase to monoclinic phase, and subsequently resulted in the decrease of monoclinic phase in ZrO2, which led to the decrease of olefin selectivity in corresponding hydrocarbon products （C2-C4/CH）.

关键词： wmonoclinic ZrO2 isosynthesis isobutene acid-base light olefins

Light People: Academician Junhao Chu

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Light(Science & Applications) 2023年第6期12卷 955-964页

作者： Hui Wang rongjun zhang Cun Yu Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of Sciences3888 Dong Nan Hu Road130033 ChangchunChina Fudan University 220 Handan RoadYangpu District200433 ShanghaiChina

Editorial The industrial revolutions of steam power,electric power and digital power have been three key steps in the development of science and ***,the fourth industrial revolution has quietly begun,a revolution which will combine the powers of modern technologies such as the Internet,industrial digitalization and virtual reality to trigger a major change of science and technology,and sensor technology is of vital importance to this process.

关键词： Academician revolution steps

Highly dispersed Ni/MgO-mSiO_(2)catalysts with excellent activity and stability for dry reforming of methane

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Nano Research 2022年第6期15卷 5004-5013页

作者： Fang Zeng Juan zhang Run Xu rongjun zhang Jianping Ge Shanghai Key Laboratory of Green Chemistry and Chemical Processes School of Chemistry and Molecular EngineeringEast China Normal UniversityShanghai 200062China Department of Coal and Syngas Conversion Research Institute of Petroleum ProcessingSINOPECBeijing 100083China

Highly dispersed Ni catalyst and alkaline promoters supported by mesoporous SiO_(2)nanospheres were synthesized and applied as an active and stable catalyst for dry reforming of methane(DRM).The as-prepared Ni/MgO-mSiO_(2)catalyst showed stable conversions of CH4 and CO_(2)around 82%and 85%in 120 h of DRM reaction,which was superior in performance compared to similar catalysts in *** on the transmission electron microscope(TEM)images,energy-dispersive spectroscopy(EDS),CO-pulse adsorption,temperature programmed reduction of the oxidized catalysts by hydrogen(H_(2)-TPR),X-ray photoelectron spectroscopy(XPS),temperature-programmed desorption of CO_(2)(CO_(2)-TPD),and thermal gravitational analysis(TGA),the promotion effect of MgO on the Ni catalyst was systematically *** introduction of Mg^(2+)in synthesis enhanced the interaction between Ni^(2+)and mSiO_(2),which led to a high dispersion of active centers and a strong“metal–support”interactions to inhibit the sintering and deactivation of Ni at reaction *** the other hand,Ni and MgO nanoparticles formed adjacently on mSiO_(2),where the“Ni-MgO”interface not only improved the Ni0 distribution and promoted the cracking of CH_(4)but also promoted the activation of CO_(2)and the elimination of carbon deposits.A high and stable conversion of CH4 and CO_(2)were then achieved through the synergistic effect of Ni catalyst,MgO promoter,and mSiO_(2)support.

关键词： Ni-based catalyst dry reforming of methane mesoporous SiO_(2) MgO alkaline

Dynamic prediction of over-excavation gap due to posture adjustment of shield machine in soft soil

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Underground Space 2024年第3期16卷 44-58页

作者： Wenyu Yang Junjie Zheng rongjun zhang Sijie Liu Wengang zhang School of Civil and Hydraulic Engineering Huazhong University of Science and TechnologyWuhan 430074China School of Civil Engineering Wuhan UniversityWuhan 430072China School of Civil Engineering Chongqing UniversityChongqing 400045China

The probability analysis of ground deformation is becoming a trend to estimate and control the risk brought by shield *** gap parameter is regarded as an effective tool to estimate the ground loss of tunnelling in soft *** specifically,x,which is a gap parameter component defined as the over(or insufficient)excavation due to the change in the posture of the shield machine,may contribute more to the uncertainty of the ground ***,the existing uncertainty characterization methods for x have several limitations and cannot explain the uncertain correlations between the relevant *** these lines,to better characterize the uncertainty of x,the multivariate probability distribution was developed in this work and a dynamic prediction was proposed for *** attain this goal,1523 rings of the field data coming from the shield tunnel between Longqing Road and Baiyun Road in Kunming Metro Line 5 were utilized and 44 parameters including the construction,stratigraphic,and posture parameters were collected to form the *** to the variance filter method,the mutual information method,and the value of the correlation coefficients,the original 44 parameters were reduced to 10 main parameters,which were unit weight,the stoke of the jacks(A,B,C,and D groups),the pressure of the pushing jacks(A,C groups),the chamber pressure,the rotation speed,and the total *** multivariate probability distribution was constructed based on the Johnson system of ***,the distribution was satisfactorily verified in explaining the pairwise correlation between x and other parameters through 2 million simulation *** last,the distribution was used as a prior distribution to update the marginal distribution of x with any group of the relevant parameters *** performance of the dynamic prediction was further validated by the field data of 3 shield tunnel cases.

关键词： Shield tunnel Ground loss Gap parameter Multivariate probability distribution Bayesian updating Dynamic prediction

A strength model for cement-stabilized mud subjected to various curing temperatures and its early-stage quality control

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第11期16卷 4727-4741页

作者： Sijie Liu rongjun zhang Junjie Zheng Lin Chen School of Civil Engineering Wuhan UniversityWuhan430072China Rock Mechanics in Hydraulic Structural Engineering Ministry of EducationWuhan430072China School of Civil and Hydraulic Engineering Huazhong University of Science and TechnologyWuhan430074China

The influence of curing temperature on the strength development of cement-stabilized mud has been well documented in terms of strength-increase rate and ultimate ***,the strength development model is not mature for the extremely early *** addition,there is a lack of studies on quality control methods based on early-stage strength *** paper presents a strength model for cement-stabilized mud to address these gaps,considering various curing temperatures and early-stage *** this study,a series of laboratory experiments was conducted on two types of muds treated with Portland blast furnace cement and ordinary Portland cement under four different *** results indicate that elevated temperatures expedite strength development and lead to higher long-term *** proposed model,which combines a three-step conversion process and a hyperbolic model at the reference temperature,enables accurate estimate of the strength development for cement-treated mud with any proportions cured under various *** this model,a practical early quality control method is introduced for applying cement-stabilized mud in field *** back-analysis parameters obtained from a 36-h investigation at temperature of 60C demonstrated a sufficient accuracy in predicting strength levels in practical applications.

关键词： Cement-stabilized mud Curing temperature Early stage Quality control Strength development

Versatile band structure and electron-phonon coupling in layered PtSe_(2) with strong interlayer interaction

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Nano Research 2022年第7期15卷 6613-6619页

作者： Junbo He Xudan Zhu Weiming Liu Ertao Hu Jianlu Wang rongjun zhang Department of Optical Science and Engineering Fudan UniversityShanghai 200433China College of Electronic and Optical Engineering Nanjing University of Posts and TelecommunicationsNanjing 210023China Institute of Optoelectronics Fudan UniversityShanghai 200433China Academy for Engineering and Technology Fudan UniversityShanghai 200433China Yiwu Research Institute of Fudan University Yiwu 322000China

The large tunability in the band structure is ubiquitous in two-dimensional(2D)materials,and PtSe_(2) is not an exception,which has attracted considerable attention in electronic and optoelectronic applications due to its high carrier mobility and long-term *** dimensional dependent properties are closely related to the evolution of electronic band *** points(CPs),the extrema or saddle points of electronic bands,are the cornerstone of condensed-matter physics and fundamentally determine the optical and transport phenomena of the layered PtSe_(2).Here,we have experimentally revealed the detailed electronic structures in layered PtSe_(2),including the CPs in the Brillouin zones(BZs),by means of reflection contrast spectroscopy and spectroscopic ellipsometry(SE).There are three critical points in the BZs attributed to the excitonic transition,quasi-particle band gap,and the band nesting effect related transition,*** CPs show red-shifting trends with increasing layer number under the mechanism of strong interlayer *** have further revealed the electron–phonon(e–ph)interaction in such layered material,utilizing temperature-dependent absorbance *** strength of e–ph interaction and the average phonon energy also decline with the increasement of layer *** findings give a deep understanding to the physics of the layer-dependent evolution of the electronic structure of PtSe_(2),potentially leading to applications in optoelectronics and electronic devices.

关键词： layered transition metal dichalcogenides PtSe_(2)thin films interlayer coupling critical points electron-phonon interaction

Synthesis and biological evaluation of ^(18)F-FB-NGA as a hepatic asialoglycoprotein receptor PET imaging agent

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Nuclear Science and Techniques 2013年第6期24卷 50-55页

作者： GU Xiaobo CAI Gangming JIANG Mengjun ZHOU Yaoyuan zhang rongjun Key Laboratory of Nuclear Medicine Ministry of HealthJiangsu Key Laboratory of Molecular Nuclear MedicineJiangsu Institute of Nuclear Medicine Department of Clinical Laboratory Science the First Wuxi Affiliated Hospital of Nanjing Medical UniversityWuxi Clinical Science Research Institute

Asialoglycoprotein receptor(ASGP-R)is a hepatic membrane receptor that uniquely exists on the surface of mammalian hepatocytes,and has been used as target of liver functional imaging agents for many *** labeled the Galactosyl-neoglycoalbumin(NGA)with 18F to get a PET molecular probe 18F-FB-NGA and evaluated its ability as a liver functional PET imaging *** 18F-FB-NGA was prepared with NGA by conjugation with Nsuccinimidyl-4-18F-fluorobenzoate(18F-SFB)and purified with PD-10 desalting *** radiolabeling yield and radiochemical purity of 18F-FB-NGA were determined by *** with 18F-F–,the total time for 18F-FB-NGA was about 120±10 *** decay-corrected radiochemical yield is about 25–30%.The radiochemical purity of purified 18F-FB-NGA was more than 98%.Labeled with 185–1850 MBq 18F-SFB,the specific activity of 18F-FBNGA was estimated to be 7.83–78.3 TBq/*** of 18F-FB-NGA in normal mice was investigated after injection through the tail *** results showed that the liver accumulated 39.47±3.42 and 12.12±6.11%ID/g at 10 and 30 min after injection,*** MicroPET images in mice were acquired with and without block after injection of the radiotracer,*** liver activity accumulation was observed at 5 min after injection in normal *** the contrary,the liver accumulation was significantly lower after block,indicating the specific binding to ASGP-R.18F-FB-NGA is probably a potential PET liver imaging agent.

关键词：去唾液酸糖蛋白受体细胞膜受体肝功能 PET 显像剂生物学评价放射化学纯度放射性标记

Steam reforming of toluene as a tar model compound with modified nickel-based catalyst

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Frontiers in Energy 2022年第3期16卷 492-501页

作者： Omeralfaroug Khalifa Mingxin Xu rongjun zhang Tahir Iqbal Mingfeng Li Qiang Lu State Key Laboratory of Alternate Electric Power System with Renewable Energy Sources North China Electric Power UniversityBeijing102206China Research Institute of Petroleum Processing SINOPECBeijing100083Chin Faculty of Agricultural Engineering and Technology PMAS-Arid Agriculture UniversityRawalpindiPakistan

Catalytic steam reforming is a promising route for tar conversion to high energy syngas in the process of biomass gasification. However, the catalyst deactivation caused by the deposition of residual carbon is still a major challenge. In this paper, a modified Ni-based Ni-Co/Al2O3-CaO (Ni-Co/AC) catalyst and a conventional Ni/Al2O3 (Ni/A) catalyst were prepared and tested for tar catalytic removal in which toluene was selected as the model component. Experiments were conducted to reveal the influences of the reaction temperature and the ratio between steam to carbon on the toluene conversion and the hydrogen yield. The physicochemical properties of the modified Ni-based catalyst were determined by a series of characterization methods. The results indicated that the Ni-Co alloy was determined over the Ni-Co/AC catalyst. The doping of CaO and the presence of Ni-Co alloy promoted the performance of toluene catalytic dissociation over Ni-Co/AC catalyst compared with that over Ni/A catalyst. After testing in steam for 40 h, the carbon conversion over Ni-Co/AC maintained above 86% and its resistance to carbon deposition was superior to Ni/A catalyst.

关键词： catalytic steam reforming tar model compound Ni-based catalyst carbon resistance

Modelling of Level Fluctuation in Continuous Casting

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Journal of Materials Science & Technology 2003年第z1期19卷 158-160页

作者： Xiao LIU Huanxin zhang rongjun XU Yongquan LI Houfa SHEN Baicheng LIU Baoshan Iron and Steel Co. LTD. Shanghai 201900 China Department of Mechanical Engineering Tsinghua University Beijing 100084 China Baoshan Iron and Steel Co. LTD. Shanghai 201900 China Baoshan Iron and Steel Co. LTD. Shanghai 201900 China Department of Mechanical Engineering Tsinghua University Beijing 100084 China Department of Mechanical Engineering Tsinghua University Beijing 100084 China

The free surface profile and fluid flow in the mold of continuous casting have been calculated by the VOF method couplingthe SIMPLER algorithm. The SIMPLER-VOF model developed is validated by solving a classical experiment, broken damproblem. The calculated surface profile is consistent with water modelling. It is found that the free surface profile is coherentlyrelated to the position of circumfluence in the mold of continuous casting. With the increase of nozzle port inclination, thepositive vortex above the jet is near to the meniscus and the level fluctuation becomes prominent.

关键词： Level fluctuation, Fluid flow, Continuous casting, Numerical simulation

Strong electron–phonon coupling influences carrier transport and thermoelectric performances in group-IV/V elemental monolayers

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npj Computational Materials 2021年第1期7卷 1287-1298页

作者： Yu Wu Bowen Hou Ying Chen Jiang Cao Hezhu Shao Yiming zhang Congcong Ma Heyuan Zhu rongjun zhang Hao zhang Key Laboratory of Micro and Nano Photonic Structures(MOE)and Key Laboratory for Information Science of Electromagnetic Waves(MOE)and Department of Optical Science and Engineering School of Information Science and TechnologyFudan UniversityShanghaiChina Department of Light Sources and Illuminating Engineering School of Information Science and TechnologyFudan UniversityShanghaiChina School of Electronic and Optical Engineering Nanjing University of Science and TechnologyNanjingChina College of Electrical and Electronic Engineering Wenzhou UniversityWenzhouChina Yiwu Research Institute of Fudan University Yiwu CityZhejiangChina Nanjing University National Laboratory of Solid State MicrostructureNanjingChina

The interactions between electrons and phonons play the key role in determining the carrier transport properties in *** this work,comprehensive investigations on full electron–phonon(el–ph)couplings and their influences on carrier mobility and thermoelectric(TE)performances of 2D group IV and V elemental monolayers are performed,and we also analyze the selection rules on el–ph couplings using group *** shallow n/p-dopings in Si,Ge,and Sn,ZA/TA/LO phonon modes dominate the intervalley *** strong intervalley scatterings via ZA/TO phonon modes can be identified for CBM electrons in P,As,and Sb,and for VBM holes,ZA/TA phonon modes dominate intervalley scatterings in P while LA phonons dominate intravalley scatterings in As and *** considering full el–ph couplings,the TE performance for these two series of monolayers are predicted,which seriously downgrades the thermoelectric figures of merits compared with those predicted by the constant relaxation time approximation.

关键词： theory phonon coupling