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Catalyst grading technology for promoting the diesel hydrocracking to naphtha

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Petroleum Science 2023年第6期20卷 3798-3806页

作者： Jia-Qi Ge Peng Zhang Fa-Min Sun Ze-An xie Zhi-jie Wu Bai-jun Liu State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing102249China Petrochemical Research Institute PetroChina Company LimitedBeijing102206China Daqing Petrochemical Research Center PetroChina Company LimitedDaqing163714HeilongjiangChina Institute of Catalysis for Energy and Environment Shenyang Normal UniversityShenyang110034LiaoningChina

This paper reports the application of multi-component hydrocracking catalyst grading technology in diesel hydrocracking system to increase naphtha,and studies the influence of catalyst systems with different number of graded beds on the reaction process of diesel *** hydrocracking catalysts with different physicochemical properties as gradation components,the diesel hydrocracking reaction on catalyst systems of one-component,two-component and three-component graded beds with different loading sequences are carried out and evaluated,*** catalytic mechanism of the multi-component grading system is *** results show that,with the increase of the number of grading beds,the space velocity of reaction on each catalyst increases,which can effectively control the overreaction process;along the flow direction of feedstock,the loading sequences of catalysts with acidity decreasing and pore properties increasing can satisfy the demand of different catalytic activity for the conversion of reactant with changing composition to naphtha,which has a guiding role in the conversion of feedstock to target ***,the conversion of diesel,the selectivity and yield of naphtha all increase significantly on the multi-component catalyst *** research on the grading technology of multi-component catalysts is of great significance to the promotion and application of catalyst systems in various catalytic fields.

关键词： Grading technology Multi-component catalysts Hydrocracking Diesel Naphtha

Organic matter fractions within macroaggregates in response to long-term fertilization in calcareous soil after reclamation

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Journal of Integrative Agriculture 2021年第6期20卷 1636-1648页

作者： CAO Han-bing xie jun-yu HONG jie WANG Xiang HU Wei HONG Jian-ping College of Resources and Environment Shanxi Agricultural UniversityTaigu 030801P.R.China Shanxi Province Key Laboratory of Soil Environment and Nutrient Resources Taiyuan 030031P.R.China College of Environment Zhejiang University of TechnologyHangzhou 310014P.R.China College of Land Science and Technology China Agricultural UniversityBeijing 100193P.R.China New Zealand Institute for Plant&Food Research Limited Christchurch 8140New Zealand

Soil organic carbon(SOC)plays a key role in improving soil quality and optimizing crop *** little is known about the fate of macroaggregates(>0.25 mm)under long-term fertilization and their relative importance in SOC sequestration in reclaimed calcareous ***,the effects of mineral fertilizers and organic manure on the mechanisms of organic carbon(OC)stabilization in macroaggregates were investigated in this *** treatments were used:unfertilized control(CK),mineral fertilizer(NPK),compost chicken manure alone(M),and mineral fertilizers plus manure(MNPK).Samples from the 0–20 cm layer of soil receiving 11-year-long fertilization were separated into four fractions based on the macroaggregates present(unprotected coarse and fine particulate organic matter,cPOM and fPOM;physically protected intra-microaggregate POM,i POM;and biochemically protected mineral associated OM,MOM)by the physical fractionation *** with the control,the long-term application of NPK had little effect on SOC content,total nitrogen(TN)content,and OC and TN contents of macroaggregate *** contrast,incorporation of organic manure(MNPK)significantly increased SOC(45.7%)and TN(24.3%)*** of MNPK increased OC contents within macroaggregate-extracted fractions of cPOM(292.2%),fPOM(136.0%)and iPOM(124.0%),and TN contents within cPOM(607.1%),fPOM(242.5%)and iPOM(127.6%),but not the mineral associated organic carbon(MOM-C)and nitrogen(MOM-N)*** C fractions were more strongly and positively correlated with SOC increase than protected C fractions,especially for cPOM-C,indicating that SOC sequestration mainly occurred via cPOM-C in the studied calcareous *** conclusion,MNPK increased the quantity and stability of SOC by increasing the contents of cPOM-C and cPOM-N,suggesting that this management practice(MNPK)is an effective strategy to develop sustainable agriculture.

关键词： long-term fertilization carbon sequestration macroaggregate physical fractionation coarse particulate organic carbon calcareous soil

Interface evolution of Cu-Ni-Si/Al-Mg-Si clad composite wires after annealing

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Rare Metals 2020年第12期39卷 1419-1424页

作者： Zhen Yang Xu-jun Mi Xue Feng Hao-Feng xie Li-jun Peng Guo-jie Huang Yan-Feng Li Xiang-Qian Yin Key Laboratory of Nonferrous Metals and Processes GRIMAT Engineering Institute Co.LtdBeijing 101400China

Interface micros tructures of Cu-Ni-Si/Al-MgSi clad composite wires during isothermal annealing from 623 to 773 K were *** composite wires were fabricated by a drawing *** evolution of intermetallic compounds(IMCs)was analyzed.A continuous IMCs layer forms only after annealing for 1 min,which may be due to more IMCs nucleation points generated by deep drawing *** consist of Al_(4)Cu_(9),AlCu and Al_(2)Cu identified by energy-dispersive spectroscopy(EDS)and transmission electron microscopy(TEM).The growth activation energies of total IMCs,Al_(2)Cu,AlCu and Al_(4)Cu_(9),are 98.8,69.4,101.3 and 137.1 kJ·mol^(-1),*** higher growth activation energy of Al_(4)Cu_(9)results in the higher growth rate under high ***,the average interdiffusion coefficient for each IMC calculated by Wagner method shows that interdiffusion in Al_(2)Cu and AlCu is more active than that in Al_(4)Cu_(9).The higher growth rate of Al_(4)Cu_(9)may be caused by the long concentration range.

关键词： Intermetallic compounds Clad composite wires Diffusion Activation energy

Microstructural evolution and properties of a Cu-Cr-Ag alloy during continuous manufacturing process

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Rare Metals 2021年第8期40卷 2213-2220页

作者： Gao-Lei Xu Li-jun Peng Guo-jie Huang Hao-Feng xie Zhen Yang Xue Feng Xiang-Qian Yin Xu-jun Mi State Key Laboratory of Nonferrous Metals and Processes GRIMAT Engineering Institute Co.Ltd.Beijing101417China Zhejiang Libo Industrial Co. Ltd.Shaoxing312050China

Microstructure evolution and properties of a Cu-Cr-Ag alloy during the continuous manufacturing process were investigated in detail by scanning electron microscopy(SEM)and transmission electron microscopy(TEM)in the *** Cu-Cr-Ag alloy rod with uniform compositions is fabricated by upward continuous casting *** of the Cr phases are observed in the ascast *** the continuous extrusion process,the severe shear deformation and the dynamic aging *** average grain size of as-extruded alloy is much smaller than that of as-cast *** fcc and bcc Cr precipitates appear in the *** interaction mode between dislocations and precipitates can be identified as Orowan bypass mode according to the TEM *** overall difference in the yield strength between as-cast and as-extruded Cu-Cr-Ag alloy is attributed to solid solution strengthening,grain refinement strengthening,precipitation hardening and working hardening.

关键词： Cu-Cr-Ag alloy Upward continuous casting Continuous extrusion Microstructure Physical properties

PROMOTING SILTATION EFFECTS AND IMPACTS OF HENGSHA EAST SHOAL ON THE YANGTZE RIVER ESTUARY

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Journal of Hydrodynamics 2011年第5期23卷 649-659页

作者： xie jun YAN Yi-xin College of Harbor Coastal and Offshore Engineering Hohai University Nanjing 210098 China Shanghai Waterway Engineering Design and Consulting Co. Ltd Shanghai 200120 China

For the Hengsha East Shoal Promoting Siltation Project in the Yangtze River Estuary, this work developed a formula for calculating sediment carrying capacity based on variable coefficients and a mathematical model for suspended sedimentation using variable saturation recovery coefficients. Not only does the model yield good verification, preferably give the hydrodynamics and the sediment concentration, but also reach a good agreement between the simulation results andlux by tide for studying the effect the measured topographical changes in the promoting siltation zone of the Hengsha East Shoal. Moreover, this article proposes a method for examing the net sediment tran- sportation fs of the project of promoting siltation and comparatively analyzes the current siltation of the Hengsha East Shoal and siltation mouth layouts, entrance widths, entrance bottom elevations, and the impact of the South Main Dike on promoting siltation through calculating the net sediment transportation flux by tide over the fixed bed and the direct movable bed numerical simulations. The results are in good agreement with each other, indicating that the method for calculating the net sedi- ment transportation flux by the tide is also useful for assessing the project in promoting siltation. Finally, we use the modeling results to analyze the water and sediment diversion ratios and the changes in silting and scouting in riverbeds and draw the conclusion that the completion of the Hengsha East Shoal Promoting Siltation Project would not adversely affect the Yangtze River Estuary Deepwater Channel Project.

关键词： Hengsha East Shoal promoting siltation effects mathematical simulation sediment diversion ratio net sediment transportation flux

Super minimal surfaces in hyper quadric Q2

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Frontiers of Mathematics in China 2020年第5期15卷 1035-1046页

作者： jun WANG jie FEI School of Mathematics Sciences and Institute of Mathematics Nanjing Normal UniversityNanjing 210023China Department of Pure Mathematics School of ScienceXi'an Jiaotong-Liverpool UniversitySuzhou 215123China

We study a superminimal surface M immersed into a hyperquadric Q2 in several cases classified by two global defined functions TX and TY,which were introduced by *** and *** to study a minimal immersion f:M→*** case both TX and TY are not identically zero,it is proved that fis superminimal if and only if f is totally real or io f:M→CP3 is also minimal,where i:Q2→CP^3 is the standard inclusion *** the rest case that TX=0 or TY=0,the minimal immersion f is automatically *** a consequence,all the superminimal two-spheres in Q2 are completely described.

关键词： Hyperquadric superminimal surface totally real holomorphic

Structure and evolution of the submarine cable network of Chinese mainland

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Journal of Geographical Sciences 2022年第5期32卷 932-956页

作者： xie Yongshun WANG Chengjin HUANG jie Institute of Geographic Sciences and Natural Resources Research CASBeijing100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing100049China

Submarine cable network is one of the most important connectivity infrastructures in the digital *** the past 20 years,the submarine cable network of Chinese mainland has formed a complex connectivity *** paper focuses on exploring the structure and evolution of the submarine cable network of Chinese *** results show that the evolution can be divided into four stages:an initial stage(1993-1998),a developmental stage(1999-2002),a stagnation stage(2003-2015)and an accelerated stage(2016-2018).The connectivity structure can be analyzed at micro,meso and macro ***,the connectivity increased significantly overall,but showed significant differences in *** the microscale,the landing cities were characterized by“extensive but low,exclusive and high”;for the mesoscale,the connectivity of countries or regions was characterized by“distance attenuation”as a whole,but,in part,by a“regional identity”;for the macroscale,intercontinental connectivity differences have been *** hierarchy has been upgraded from a“3 system”to a“2+3 system”.Finally,this paper discusses the interaction between submarine cable network construction and international relations,and puts forward policy suggestions for China’s submarine cable construction.

关键词： submarine cable network structure connectivity evolution Chinese mainland

Integrated water risk early warning framework of the semi-arid transitional zone based on the water environmental carrying capacity (WECC)

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Journal of Arid Land 2023年第2期15卷 145-163页

作者： xie Yuxi ZENG Weihua QIU jie School of Environment Beijing Normal UniversityBeijing 100875China Northwest Institute of Plateau Biology Chinese Academy of SciencesQinghai 810008China Nanjing Institute of Environmental Sciences Ministry of Ecology and EnvironmentNanjing 210042China

Water risk early warning systems based on the water environmental carrying capacity(WECC)are powerful and effective tools to guarantee the sustainability of *** work on the early warning of WECC has mainly concerned the comprehensive evaluation of the status quo and lacked a quantitative prejudgement and warning of future *** addition,existing quantitative methods for short-term early warning have rarely focused on the integrated change trends of the early warning *** the periodicity of the socioeconomic system,however,the water environmental system also follows a trend of cyclical ***,it is meaningful to monitor and use this periodicity for the early warning of the *** this study,we first adopted and improved the prosperity index method to develop an integrated water risk early warning *** also constructed a forecast model to qualitatively and quantitatively prejudge and warn about the development trends of the water environmental *** selected the North Canal Basin(an essential connection among the Beijing-Tianjin-Hebei region)in China as a case study and predicted the WECC in 25 water environmental management units of the basin in 2018–*** found that the analysis of the prosperity index was helpful in predicting the WECC,to some *** result demonstrated that the early warning system provided reliable prediction(root mean square error of 0.0651 and mean absolute error of 0.1418),and the calculation results of the comprehensive early warning index(CEWI)conformed to the actual situation and related research in the river *** 2008 to 2023,the WECC of most water environmental management units in the basin had improved but with some spatial differences:the CEWI was generally poor in areas with many human disturbances,while it was relatively good in the upstream regions with higher forest and grass covers as well as in the downstream areas with larger water ***,through a sensitiv

关键词： water risk early warning system water environmental carrying capacity prosperity index water management North Canal(Beiyun River)

Single-material Solvent-sensitive Fluorescent Actuator from Carbon Dots Inverse Opals Based on Gradient Dewetting

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Chinese Journal of Polymer Science 2017年第9期35卷 1043-1043,1044-1050页

作者： jun-chao Liu Yuan-yuan Shang Da-jie Zhang Zheng xie 胡瑞祥王京霞 College of Chemistry and Chemical Engineering Hunan Normal University Changsha 410081 China Key Laboratory of Bio-inspired Materials and Interface Sciences Technical Institute of Physics and ChemistryChinese Academy of Sciences Beijing 100190 China Laboratory of Bioinspired materials School of Future Technology University of Chinese Academy of Sciences

A novel solvent-sensitive fluorescent actuator with reversibility has been obtained from carbon dots （CDs） inverse opals, which is prepared via infiltrating CDs solution into the interstice of colloidal crystal template, thermal polymerization of CDs materials and removing the colloidal template. The as-prepared CDs inverse opal actuator shows a bending angle of 75° in 10.2 s, bending rate of 7.35 （°）.s-1. In particular, the fluorescence intensity of the films varies during the actuating process. The actuating behavior is attributed to the inhomogeneous swelling/shrinking of the film, which originates from the gradient dewetting by solvent evaporation and hydrogen-bonding interaction between the solvent molecules and oxygen/hydrogen ions of CDs side chain. The CDs inverse opal actuator has the advantages of quick response, good repeatability and strong fluorescence, which gives an important insight into the design and manufacture of novel and advanced solvent-actuators.

关键词： Carbon dots inverse opal Fluorescent Single-material Gradient dewetting Solvent-actuator