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Non-destructive study of fruits using grating-based X-ray imaging

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Nuclear Science and Techniques 2017年第2期28卷 57-60页

作者： sheng-xiang wang Ren-Fang Hu Kun Gao Faiz Wali Gui-Bin Zan Da-Jiang wang Zhi-Yun Pan Shi-Qiang Wei National Synchrotron Radiation Laboratory University of Science and Technology of China Hefei 230029 China

Grating-based X-ray imaging can make use of conventional tube sources to provide absorption, refraction and scattering contrast images from a single set of projection images efficiently. In this paper, a fresh cherry tomato and a dried umeboshi are imaged by using X-ray Talbot–Lau interferometer. The seed distribution in the scattering image of the cherry tomato, and the wrinkles of epicarp in the refraction image of the umeboshi, are shown distinctly. The refraction and scattering images provide more information on subtle features than the absorption image. Also, the contrast-to-noise ratio values show distinguishing capacity of the three kinds of imaging techniques. The results confirm that grating-based X-ray imaging is of great potential in non-destructive fruit testing.

关键词： Non-destructive testing X-ray imaging Talbot–Lau interferometer Fruit testing

Cobalt-catalyzed Photochemical Methoxycarbonylation of Olefins with Carbon Dioxide under Ambient Conditions

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Chinese Chemical Letters 2000年第3期11卷 223-224页

作者： Jing Mei YIN Ming GUO Rui wang Guang Yun ZHOU Da Bin GAO xiang sheng wang Xin Wen GUO Jian Qin ZHUANG Department of Chemisiry&Chemical Engineering Dalian UniversityDalian 116622 Open Laboratory of Carbon Resource Utilization Dalian University of TechnologyDalian 116012 Dalian Institute of Chemical Physics The Chinese Academy of SciencesDalian 116023

The methoxycarbonylations of cyclohexene and 1-decene with CO2 can take place under ambient conditions by catalysis of [Co]([Co]=Co(acac)(2), Co(OAc)(2), CoCl2) in the presence of ultraviolet irradiation.

关键词： carbon dioxide methoxycarbonylation cobalt catalyst

Photopromoted Carbonylation of Alkyl Bromides Catalyzed by Copper Salts under Ambient Conditions

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Chinese Chemical Letters 2005年第11期16卷 1455-1458页

作者： Tao WEN Ying Ping JIA Da Bin GAO Jing Mei YINI Guang Yun ZHOU Jing LIU xiang sheng wang Liaoning Key Laboratory of Bio-Organic Chemistry Dalian University Dalian 116622 State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian 116012

Photopromoted carbonylation of alkyl bromides with carbon monoxide or carbon dioxide catalyzed by copper salts can be carried out under ambient conditions （atmospheric pressure and room temperature） and the corresponding ester was produced. The yield and the selectivity of the ester can be improved greatly by addition of sodium phosphate.

关键词： Photopromoted carbonylation carbon monoxide carbon dioxide copper salts.

The Simulation and Experimental Validation on Gas-Solid Two Phase Flow in the Riser of a Dense Fluidized Bed

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Journal of Thermal Science 2009年第2期18卷 137-141页

作者： Xue-yao wang Fan Jiang xiang Xu sheng-dian wang Bao-guo Fan Yun-han Xiao Key Laboratory of Advanced Energy and Power, Chinese Academy of Sciences (Institute of Engineering Thermophysics) Beijing 100190 Key Laboratory of Advanced Energy and Power Chinese Academy of Sciences (Institute of Engineering Thermophysics) Beijing 100190 China

Gas-solid flow in dense CFB (circulating fluidized bed)) riser under the operating condition, superficial gas 15.5m/s and solid flux 140 kg/m2s using Geldart B particles (sand) was investigated by experiments and CFD (computationalfluid dynamics) simulation. The overall and local flow characteristics are determined using the axialpressure profiles and solid concentration profiles. The cold experimental results indicate that the axial solid concentration distribution contains a dilute region towards the up-middle zone and a dense region near the bottomand the top exit zones. The typical core-annulus structure and the back-mixing phenomenon near the wall of theriser can be observed. In addition, owing to the key role of the drag force of gas-solid phase, a revised drag forcecoefficient, based on the EMMS (energy-minimization multi-scale) model which can depict the heterogeneouscharacter of gas-solid two phase flow, was proposed and coupled into the CFD control equations. In order to findan appropriate drag force model for the simulation of dense CFB riser, not only the revised drag force model butsome other kinds of drag force model were used in the CFD. The flow structure, solid concentration, clustersphenomenon, fluctuation of two phases and axial pressure drop were analyzed. By comparing the experimentwith the simulation, the results predicted by the EMMS drag model showed a better agreement with the experimentalaxial average pressure drop and apparent solid volume fraction, which proves that the revised drag forcebased on the EMMS model is an appropriate model for the dense CFB simulation.

关键词： riser gas-solid flow drag force EMMS model

Cobalt-catalyzed photopromoted carbonylation of chloroalkanes in the presence of KI

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Chinese Chemical Letters 2010年第9期21卷 1033-1036页

作者： Ying Ping Jia Ying Na Cui Jing Mei Yin Guang Yun Zhou Shen Min Li Da Bin Gao xiang sheng wang State Key Laboratory of Fine Chemicals Dalian University of Technology. Dalian 116012 China Liaoning Key Laboratory of Bio-organic Chemistry Dalian University Dalian 116622China

The photopromoted carbonylation of chloroalkanes with carbon monoxide catalyzed by cobalt compounds[Co（OAc）2,CoCl2] in the presence of KI was carried out under ambient *** results revealed that the catalytic activity of Co（OAc）2 was higher than that of CoCl2.A basic additive NaOAc was beneficial to the ***,with NaOAc as an additive, Co（OAc）2 and CoCl2 exhibited similar catalytic *** work showed that the role of iodide ion was initially to form active iodoalkanes via substituting chloride ion in chloroalkanes in situ,and then,the carbonylation of iodoalkanes proceeded under irradiation.

关键词： Photopromoted carbonylation Chloroalkanes Cobalt complexes: KI

Ring artifacts correction based on the projection-field in neutron CT

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Chinese Physics B 2021年第5期30卷 267-271页

作者： sheng-xiang wang Jie Chen Zhi-Jian Tan Si-Hao Deng Yao-Da Wu Huai-Le Lu Shou-Ding Li Wei-Chang Chen Lun-Hua He Spallation Neutron Source Science Center Dongguan 523803China Institute of High Energy Physics Chinese Academy of Sciences(CAS)Beijing 100049China Institute of Physics Chinese Academy of SciencesBeijing 100190China Key Laboratory of Shale Gas and Geoengineering Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

Ring artifacts will happen mostly when the detector has inconsistent response among the detector channels,and the characteristic produced rings centered in the iso-center in the reconstructed slices inevitably affect the recognition and analysis of the corresponding sample structures in neutron computed tomography(CT).In this work,a ring correction method based on the projection-field(RCP)is proposed,it is a pre-processing method and provides the corrected projection data directly,which is also conducive to efficient data storage and other algorithmic *** and physical experiments are performed for verifying the effect of the method,and one of the correction methods based on the image-field is used for *** results demonstrate that the RCP can correct the ring artifacts well without reducing the image resolution or over-correction.

关键词： ring artifacts correction neutron CT projection field

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张量余单子与张量范畴

数学学报（中文版） 2014年第3期57卷 485-492页

作者：张晓辉王圣祥东南大学数学系南京210096 滁州学院数学科学学院滁州239000

设是一个张量范畴,g和F均为上的张量余单子,p是一个余单子分配率.本文从FG的张量余单子结构和2-范畴的角度,描述了双余模范畴的张量结构,并给出了其做成张量范畴的一些充要条件.’

关键词：余单子双余模张量范畴 2-范畴

A multivariate analysis of the prognostic factors of grade Ⅲ gliomas

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Chinese Medical Journal 2008年第12期121卷 1072-1075页

作者： ZHU Yong-jian ZHU xiang-dong wang sheng-hu SHEN Fang SHEN Hong LIU Wei-guo Department of Neurosurgery Second Affiliated Hospital of Zhejiang University School of Medicine Hangzhou Zhejiang 310009 China

Background Glioma is the most common type of malignant brain tumor and the prognosis of glioma is still poor. Moreover, the prognosis of patients diagnosed with grade Ⅲ gliomas varies significantly. In this study, we assessed the factors that contribute to the prognosis of patients with grade Ⅲ gliomas.Methods Data from 97 patients with grade Ⅲ glioma who received surgery from 2000 to 2005 were included in this study. Kaplan-Meier survival analysis and Cox regression analysis were used to analyze the prognostic effects of 16 different factors selected from clinical characteristics, results from neuroimaging and pathological examinations, as well as different treatment schemes.Results The results indicated that age, preoperative Karnofsky Performance Scale score, extent of tumor invasion, tumor resection degree, residual tumor shown by postoperative magnetic resonance imaging （MRI）, and postoperative radiotherapy and chemotherapy all correlated with patient prognosis. Furthermore, Cox multivariate analysis also showed the age （P 〈0.01）, extent of tumor invasion （P 〈0.01）, residual tumor shown by postoperative MRI （P 〈0.05）, and postoperative radiotherapy （P 〈0.05） significantly correlated with patients＇ prognosis.Conclusions Age, postoperative radiotherapy and residual tumor indicated by MRI after surgery correlated significantly with the prognosis of patients with grade Ⅲ glioma. The extent of tumor invasion may be an independent prognostic factor for patients with grade Ⅲ glioma.

关键词： grade Ⅲ glioma prognosis Cox model

Boosting Oxygen Evolution Reaction Performance on NiFe‑Based Catalysts Through d‑Orbital Hybridization

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Nano-Micro Letters 2025年第1期17卷 281-292页

作者： Xing wang Wei Pi sheng Hu Haifeng Bao Na Yao Wei Luo State Key Laboratory of New Textile Materials and Advanced Processing Technology Key Laboratory of New Textile Materials and Applications of Hubei ProvinceSchool of Materials Science and EngineeringWuhan Textile UniversityWuhan 430200People’s Republic of China College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072People’s Republic of China

Anion-exchange membrane water electrolyzers(AEMWEs)for green hydrogen production have received intensive attention due to their feasibility of using earth-abundant NiFe-based *** introducing a third metal into NiFe-based catalysts to construct asymmetrical M-NiFe units,the d-orbital and electronic structures can be adjusted,which is an important strategy to achieve sufficient oxygen evolution reaction(OER)performance in ***,the ternary NiFeM(M:La,Mo)catalysts featured with distinct M-NiFe units and varying d-orbitals are reported in this *** and theoretical calculation results reveal that the doping of La leads to optimized hybridization between d orbital in NiFeM and 2p in oxygen,resulting in enhanced adsorption strength of oxygen intermediates,and reduced rate-determining step energy barrier,which is responsible for the enhanced OER *** critically,the obtained NiFeLa catalyst only requires 1.58 V to reach 1 A cm^(−2) in an anion exchange membrane electrolyzer and demonstrates excellent long-term stability of up to 600 h.

关键词： NiFe-based catalysts d-orbital coupling Oxygen evolution reaction Anion exchange membrane electrolyzer