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The effect of the Ce content on the oxidative dehydrogenation of propane over CrOy-CeO2/γ-Al2O3 catalysts

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Chinese Journal of Chemical Engineering 2020年第12期28卷 3035-3043页

作者： Cheng Zuo man Wu Qingjie Guo Key Laboratory of Clean Chemical Processing of Shandong Province College of Chemical EngineeringQingdao University of Science and TechnologyQingdao 266042China State Key Laboratory of High-efficiency Coal Utilization and Green Chemical Engineering College of Chemistry and Chemical EngineeringNingxia UniversityYinchuan 750021China

A series of CrOy(17.5 wt%)-CeO2(X wt%)/γ-Al2O3 catalysts(X=0,0.5,2,5,8)with various Ce contentswere prepared by a wetness impregnation method and were applied to the dehydrogenation of propane to propylene at 550℃ and 0.1 *** prepared catalysts were characterized by BET,H2-TPR,O2-TPD,XPS,XRD,SEM-EDS and Raman *** the prepared catalysts,the 17.5Cr-2Ce/Al catalyst with the largest amount of lattice oxygen exhibited the best catalytic performance for the dehydrogenation of propane to propylene with lattice *** decreased presence of oxygen defects and reducibility were the factors responsible for the improved dehydrogenation activity of the *** CeO2 layer could inhibit the evolution of lattice oxygen(O2^−)to electrophilic oxygen species(O2^−),and the oxygen defects on the catalyst surfacewere *** inhibited lattice oxygen evolution prevented the deep oxidation of propane or propylene,the average COx selectivity decreased from 24.41%(17.5Cr/Al)to 5.71%(17.5Cr-2Ce/Al),and the average propylene selectivity increased from 60.15%(17.5Cr/Al)to 85.05%(17.5Cr-2Ce/Al).

关键词： Oxidation Selectivity Propane Propylene Fluidized-bed Oxygen carrier

A more general form of lump solution,lumpoff,and instanton/rogue wave solutions of a reduced (3+1)-dimensional nonlinear evolution equation

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Chinese Physics B 2018年第12期27卷 147-156页

作者： Panfeng Zheng man Jia Physics Department Ningbo UniversityNingbo 315211China Ningbo Collaborative Innovation Center of Nonlinear Hazard System of Ocean and Atmosphere Ningbo UniveisityNingbo 315211China

In this manuscript,a reduced(3+1)-dimensional nonlinear evolution equation is *** first construct the bilinear formalism of the equation by using the binary Bell polynomials theory,then explore a lump solution to the special case for z=***,a more general form of lump solution of the equation is found which possesses seven arbitrary parameters and four constraint *** cutting the lump by the induced soliton(s),lumpoff and instanton/rogue wave solutions are also constructed by the more general form of lump solution.

关键词： a reduced(3 + 1)-dimensional nonlinear evolution equation more general form of lump solution soliton induced by lump lumpoff and instanton/rogue wave solutions

Global adaptive stabilization for planar nonlinear systems with unknown input powers

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Science China(Information Sciences) 2021年第9期64卷 261-263页

作者： Yongchao man Yungang LIU School of Control Science and Engineering Shandong University

Dear editor,Despite the development of extensive strategies [1,2], adaptive control still requires thorough investigations to improve its capability and cover more uncertain systems. This study aims to demonstrate the powerful ability of adaptive control in compensating multiple serious uncertainties, particularly those in input powers,

关键词： Nonlinear systems multiple serious uncertainties unknown input powers adaptive control global stabilization

Burning characteristics of high density foamed GAP/CL-20 propellants

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Defence Technology（防务技术） 2022年第10期18卷 1914-1921页

作者： man-man Li Rui Hu Ming-hui Xu Qiong-lin Wang Wei-tao Yang Xi'an Modern Chemistry Research Institute Xi'an710065PR China School of Physics Xi'an Jiaotong UniversityXi'an710049PR China

The monolithic foamed propellants with high densities were prepared by casting and two-step foaming *** azide polymer(GAP)and isocyanate were used as the binder system and 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane(HNIW,CL-20)was employed as the energetic *** newly designed formulation containing 60%CL-20 produced a force constant of 1077 J/g and low flame temperature of 2817 *** foamed propellants with densities of 1.32 g/cm^(3)and 1.53 g/cm^(3)were fabricated by a confined foaming process and examined by closed bomb *** results revealed that porosity significantly affects burning performance.A size effect on combustion behaviors was observed for the foamed propellant with 5.56%porosity,and a double-hump progressive dynamic vivacity curve was *** last,the 30 mm gun test was carried out to demonstrate the interior ballistic performance,and the muzzle velocity increased by 120 m/s at the same maximum chamber pressure when monolithic propellant was added in the charge.

关键词： Monolithic foamed propellants Two-step foaming process Casting process GAP/CL-20

Regional-scale Surface Air Temperature and East Asian Summer Monsoon Changes during the Last Millennium Simulated by the FGOALS-gl Climate System Model

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Advances in Atmospheric Sciences 2014年第4期31卷 765-778页

作者： man Wenmin ZHOU Tianjun State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Key Laboratory of Meteorological Disaster of Ministry of Education Nanjing University of Information Science and Technology Climate Change Research Center Chinese Academy of Sciences

The spatial patterns and regional-scale surface air temperature （SAT） changes during the last millennium,as well as the variability of the East Asian summer monsoon （EASM） were simulated with a low-resolution version of Flexible Global Ocean-Atmosphere-Land-Sea-ice （FGOALS-gl） *** model was driven by both natural and anthropogenic forcing *** features of the simulated past millennial Northern Hemisphere （NH） mean SAT variations,including the Medieval Climate Anomaly （MCA）,the Little Ice Age （LIA） and the 20th Century Warming （20CW）,were generally consistent with the *** simulated MCA showed a global cooling pattern with reference to the 1961-90 mean conditions,indicating the 20CW to be unprecedented over the last millennium in the *** LIA was characterized by pronounced coldness over the continental extratropical NH in both the reconstruction and the *** simulated global mean SAT difference between the MCA and LIA was 0.14°C,with enhanced warming over high-latitude NH continental *** between the simulation and the reconstruction on regional scales were lower than those on hemispheric *** major features agreed well between the simulated and reconstructed SAT variations over the Chinese domain,despite some inconsistency in details among different *** EASM circulation during the MCA was stronger than that during the LIA The corresponding rainfall anomalies exhibited excessive rainfall in the north but deficient rainfall in the *** the zonal and meridional thermal contrast were enhanced during the *** temperature anomaly pattern favored a stronger monsoon circulation.

关键词： last millennium surface air temperature spatial patterns regional-scale variation East Asian summer monsoon

Responses of soil nitrogen, phosphorous and organic matter to vegetation succession on the Loess Plateau of China

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Journal of Arid Land 2015年第2期7卷 216-223页

作者： man Cheng Shao Shan AN College of Natural Resources and Environment Northwest A&F University State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Northwest A&F University

Revegetation is a traditional practice widely used for soil protection. We evaluated the effect of natural revegetation succession on soil chemical properties and carbon fractions （particulate organic carbon （POC）, humus carbon （HS-C）, humic acid carbon （HA-C） and fulvic acid carbon （FA-C）） on the Loess Plateau of China. The vegetation types, in order from the shortest to the longest enclosure duration, were：（a） abandoned overgrazed grassland （AbG3; 3 years）; （b） Hierochloe odorata Beauv. （HiO7; 7 years）; （c） Thymus mongoficus Ronnm （ThM15; 15 years）; （d） Artemisia sacrorum Ledeb （AtS25; 25 years）; （e） Stipa bungeana Trin Ledeb （StB36; 36 years） and （f） Stipa grandis P. Smirn （StG56; 56 years）. The results showed that the concentrations of soil organic carbon, total nitrogen and available phosphorus increased with the increase of restoration time except for ThM15. The concen- tration of NH4-N increased in the medium stage （for ThM15 and AtS25） and decreased in the later stage （for StB36 and StG56） of vegetation restoration. However, NO3-N concentration significantly increased in the later stage （for StB36 and StG56）. Carbon fractions had a similar increasing trend during natural vegetation restoration. The con- centrations of POC, HS-C, FA-C and HA-C accounted for 24.5%-49.1%, 10.6%-15.2%, 5.8%-9.1% and 4.6%-6.1% of total carbon, respectively. For AbG3, the relative changes of POC, HS-C and FA-C were significantly higher than that of total carbon during the process of revegetation restoration. The higher relative increases in POC, HS-C and FA-C confirmed that soil carbon induced by vegetation restoration was sequestrated by higher physical and chemical protection. The increases of soil C fractions could also result in higher ecological function in semiarid grassland ecosystems.

关键词： particulate organic carbon humus carbon humic acid carbon fulvic acid carbon carbon fraction natural vegetation succession

Evaluating the historical,clinical,and cultural value of the Tian Hui Yi Jian

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Journal of Traditional Chinese Medicine 2024年第1期44卷 220-221页

作者： YU Linyong GU man China Academy of Chinese Medical Sciences Beijing 100700China Institute for History of Medicine and Medical Literature China Academy of Chinese Medical SciencesBeijing 100700China

Tian Hui Yi Jian was compiled by the Tianhui Medical manuscripts Compilation Group,which includes scholars from the Institute for History of Medicine and Medical Literature of the China Academy of Chinese Medical Sciences(CACMS),Chengdu University of Traditional Chinese Medicine,Chengdu Institute of Cultural Relics and Archaeology,and Jingzhou Cultural Relics Protection *** was published by the Cultural Relics Press in November *** volume includes images of eight medical manuscripts,along with the Team's annotations,and photographs of a lacquered figurine with meridian-channels and words on its surface.

关键词： surface Chengdu Tian

Molecular Diversity of Three-Component Reaction of β-Enamino Imide, Malononitrile and Cyclic α-Diketones

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Chinese Journal of Chemistry 2017年第9期35卷 1422-1430页

作者： man Xiao Chaoguo Yan College of Chemistry & Chemical Engineering Yangzhou University Yangzhou Jiangsu 225002 China

The base promoted three-component reaction of β-enamino imide, malononitrile and various cyclic α-diketones in acetonitrile showed interesting molecular diversity. The reactions with acenaphthylene-1,2-dione and ninhydrin afforded functionalized spiro[indene-2,4＇-pyrrolo[3,4-b]pyridines] and spiro[acenaphthylene-1,4＇-pyrrolo[3,4-b]- pyridines] in good yields. The similar reaction of phenanthrene-9,10-dione resulted in the formation of the unexpected complex phenanthro[9＇, 10＇：4,5]furo[2,3-c]pyrrolo[3,4-b]pyrroles in satisfactory yields.

关键词： multicomponent reaction β-enamino imide spiro compound ninhydrin phenanthrene-9,10-dione

Fabrication and characteristics of magnesium alloys produced via powder metallurgy

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中国有色金属学会会刊：英文版 2000年第6期10卷 757-760页

作者：曹鹏 LU Li man On LAI Department of Mechanical and Production Engineering National University of SingaporeSingapore 119260 State Key Laboratory for Powder Metallurgy Central South UniversityChangsha 410083P.R.China

Magnesium aluminum alloy materials were fabricated via powder metallurgy. Microstructural evolution, thermal stability, tensile properties and fracture mechanism of the hot extruded magnesium alloys were investigated. Microstructural observation revealed that all alloys have fine equiaxed grains due to dynamic recrystallization during hot extrusion with Mg 17 Al 12 precipitating along grain boundaries. The DSC analyses exhibited that because diffusion rate of Al into Mg is slow in solid state sintering process, Al concentration in localized region after sintering is still high enough to cause eutectic reaction. The tensile test showed that 0.2% yield strength, ultimate tensile strength and elastic modulus increase and elongation decrease with increasing Al content. Mg 9%Al obtains the best combination of mechanical properties among the investigated alloys. Fracture surface observation showed ductile fracture to be a dominant failure mode. Abundant dimples and tear ridges are found in the fracture surfaces. Grain boundary weakening results from the precipitate Mg 17 Al 12 caused intergranular cracks during tensile test. [

关键词： magnesium alloys mechanical properties powder metallurgy hot extrusion