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Methylation of 2-methylnaphthalene with methanol to 2,6-dimethylnaphthalene over HZSM-5 modified by NH_4F and SrO

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Chinese Chemical Letters 2007年第10期18卷 1281-1284页

作者： Chen Zhang Xin Wen Guo Ya Nan wang xiang sheng wang Chun Shan Song State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian 116012 China Clean Fuels and Catalysis Program The Energy Institute and Department of Energy ＆ Geo-Environmental Engineering The Penmylvania State University 209 Academic Projects Building University Park PA 16802 USA

The methylation of 2-methylnaphthalene （2-MN） into 2,6-dimethylnaphthalene （2,6-DMN） was investigated over the solid acid catalysts. The results show that HZSM-5 modified by NH4F has better catalytic performance than parent HZSM-5 due to the decrease in the acidity. When NH4F/HZSM-5 is further modified by SrO, its catalytic activity decreases due to the decrease in the total acid amount and acidic strength. As a result, the comprehensive modification of NH4F and SrO leads to the inere, ase in the 2,6- DMN selectivity （2,6-DMN to DMN）, up to 64.8% when 2-MN conversion is 10%. We calculated the ESP charge by density functional theory and the results show that the 6-position in 2-MN has higher ESP charge value than 7-position. The formation of 2,6-DMN is favored energetically as compared to that for 2,7-DMN. This suggests during the alkylation of 2-MN inside the ZSM-5 channel, the formation of 2,6-DMN is favored electronically than that of 2,7-DMN. Hence, lowering the acidity of catalyst is a key factor to obtain high selectivity of 2,6-DMN.

关键词： 2,6-DMN, Modification Selectivity ESP charge

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.

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

Cross-Reference Benchmarks for Translating the Genetic Soil Classification of China into the Chinese Soil Taxonomy

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Pedosphere 2006年第2期16卷 147-153页

作者： SHI Xue-Zheng YU Dong-sheng YANG Guo-xiang wang Hong-Jie SUN Wei-Xia DU Guo-Hua State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing210008 （China）.

Soil classification is the foundation for exchange and extension of research findings in soil science and for modern management of soil resources. This study explained database and research methodology to create a cross-reference system for translating the Genetic Soil Classification of China (GSCC) into the Chinese Soil Taxonomy (CST). With the help of the CST keys, each of the 2 540 soil species in GSCC has been interpreted to its corresponding soil order, suborder, great group, and sub-group in CST. According to the methodology adopted, the assigned soil species have been linked one another to their corresponding polygons in the 1:1000000 digital soil map of China. Referencibility of each soil species between the GSCC and CST systems was determined statistically on the basis of distribution area of each soil species at a high taxon level of the two systems. The soils were then sorted according to their maximum referencibility and classified into three categories for discussion. There were 19 soil great groups in GSCC with maximum referencibility > 90% and 22 great groups between 60%-90%. These soil great groups could serve as cross-reference benchmarks. There were 19 great groups in GSCC with maximum referencibility < 60%, which could be used as cross-reference benchmarks until new and better results were available. For these soils, if the translation was made at a lower soil taxon level or on a regional basis, it would improve their referencibility enabling them to serve as new cross-reference benchmarks.

关键词： 1:1 000 000 soil map of China cross-reference benchmark CST GSCC referencibility

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

渐进性全身垂直振动治疗方案对缺血性脑卒中偏瘫早期患者下肢功能与平衡功能的影响

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中国康复医学杂志 2017年第3期32卷 297-300页

作者：王盛王翔王彤顾昭华江苏省人民医院(南京医科大学第一附属医院)康复医学中心南京210029

目的:探讨一种渐进性全身振动治疗方案对缺血性脑卒中偏瘫早期患者下肢功能与平衡功能的影响。方法:选择符合入组条件的患者30例,随机分为对照组与垂直振动组。垂直振动组在常规康复治疗的基础上,进行渐进性全身垂直振动治疗方案;对照... 详细信息

目的:探讨一种渐进性全身振动治疗方案对缺血性脑卒中偏瘫早期患者下肢功能与平衡功能的影响。方法:选择符合入组条件的患者30例,随机分为对照组与垂直振动组。垂直振动组在常规康复治疗的基础上,进行渐进性全身垂直振动治疗方案;对照组在常规康复治疗的基础上,站在垂直振动平台,不开启振动治疗。一天1次,每次15min,每周5天,共3周。分别在治疗前后评估患侧下肢肌张力(股四头肌,小腿三头肌),Fugl-Meyer下肢功能,Berg平衡量表。结果:治疗前垂直振动组与对照组比较各指标间无显著性差异(P>0.05);与治疗前比较,治疗后两组患者的FuglMeyer下肢评分及Berg平衡均较治疗前显著提高(P0.05),Berg平衡评分的差值有显著性意义(P<0.05),小腿三头肌肌张力差值变化有显著性意义(P<0.05)。结论:与常规康复治疗比较,3周全身垂直振动治疗对缺血性脑卒中偏瘫早期患者的下肢功能无显著改善,但能提高患者的平衡功能。

关键词：缺血性脑卒中下肢功能平衡功能肌张力

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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