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Investigation of oil and water migrations in lacustrine oil shales using 20 MHz 2D NMR relaxometry techniques

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Petroleum Science 2022年第3期19卷 1007-1018页

作者： Bo Liu Xiao-Wen Jiang Long-Hui Bai rong-sheng Lu Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments Southeast UniversityNanjingJiangsu 211189China State Key Laboratory Cultivation Base for Accumulation and Development of Unconventional Oil and Gas Northeast Petroleum UniversityDaqingHeilongjiang 163318China School of Mechanical Engineering Southeast UniversityNanjingJiangsu 211189China State Key Laboratory of Bioelectronics Southeast UniversityNanjingJiangsu 211189China

The behavior of oil and water in tight rocks can change the distribution of oil or water in pores,which affects the production of crude *** Magnetic Resonance(NMR)method is an effective and nondestructive tool for evaluating rocks with comparison and analysis both quantitatively and *** our study,20 MHz NMR Relaxometry is used as a key technique to study the changes of water and oil behaviors in Chinese lacustrine Qingshankou shales under different saturated states(imbibition and evaporation without pressure).The results show that variation in different proton populations(water,oil and organic)can be distinguished using 2D T_(1)-T_(2)*** comparison among T_(1)-T_(2)maps with different saturated states shows that different signal regions changed during oil and water migrations,which the 1D NMR Relaxometry may be not easy to *** with the pyrolysis analysis,T2 shift and differences of signal regions in T_(1)-T_(2)maps can reflect properties such as wettability and composition(organic matter,clay and magnetic minerals)to some *** study provides better insight into oil and water behaviors in lacustrine oil shales with further understanding of 20 MHz NMR 2D T_(1)-T_(2)maps both in qualitative and quantitative analysis.

关键词： NMR Relaxometry Lacustrine oil shales Oil and water migrations T_(1)-T_(2)map

Moments of the Time of Ruin,Surplus Before Ruin and the Deficit at Ruin in the Erlang(N) Risk Process

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Acta Mathematicae Applicatae Sinica 2006年第4期22卷 599-606页

作者： Yong-sheng Xing rong Wu Mathematics and Information Science College Shandong Institute of Business and Technology Yantai 264005 China School of Mathematics Nankai University Tianjin 300071 China

In this paper we consider the ＂penalty＂ function in the Erlang（n） risk model. Using the integro- differential equation we established, we obtain the explicit expressions for the moments of Erlang（2） risk model. When the claim size distribution is Light-Tailed and the penalty function is bounded, we obtain the exact representations for the moments of Erlang（n） risk model.

关键词： Penalty function Erlang(n) risk model integro-differential equation light-tailed distribution

Evolution of the Southern Yellow Sea Cold Water Mass during the last 7 kyr from benthic foraminiferal evidence

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Science China Earth Sciences 2018年第10期61卷 1406-1418页

作者： Fuchang ZHONG rong XIANG Yiping YANG Meixun zhao Key Laboratory of Ocean and Marginal Sea Geology South China Sea Institute of Oceanology Chinese Academy of SciencesGuangzhou 510301 China University of Chinese Academy of Sciences Beijing 100039 China Key Laboratory of Marine Chemistry Theory and Technology Ministry of Education Ocean University of ChinaQingdao 266100 China

The Southern Yellow Sea Cold Water Mass(YSCWM) is closely related to the modern circulation system of the east China shelf seas, which has significantly influenced regional marine environmental changes. The study of the Holocene evolution of the YSCWM will greatly improve our understanding of the mechanisms of regional environmental change. Benthic foraminifera are sensitive to bottom water environmental changes and can serve as useful indicators in bottom water environmental reconstruction. In this study, benthic foraminifera were analyzed in core N02 from the northwestern margin of the southern Yellow Sea Mud to decipher the phase evolution of the YSCWM during the last 7 kyr. Benthic foraminifera census counts and Q-mode factor analysis indicate that the Holocene sedimentary environment can be divided into three stages: From6.9–5.0 ka, the fauna was dominated by Ammonia ketienziensis, indicating that the YSCWM was at its strongest during the last 7 kyr, while the Yellow Sea Coastal Current(YSCC) had a weak influence on the bottom water of the study area. From 5.0–2.9 ka,the relative abundance of Hanzawaia nipponica remarkably increased while the abundance of A. ketienziensis decreased significantly, reflecting that the strength of the YSCWM was relatively weak and the range of the YSCWM might have contracted. The influence of the YSCC on the bottom water might have slightly increased, although its influence was still weak during this time. A notable increase in low-temperature and low-salinity species, such as Protelphidium tuberculatum and Buccella spp. has occurred since 2.9 ka, indicating that the YSCC has had a strong influence on bottom water during this period,while the strength of the YSCWM has been at its weakest during the last 7 kyr. Generally, the influence of the YSCWM and the YSCC on the bottom water properties of the study area show an obvious seesaw pattern, with one's influence increasing while the other's influence decreases and vice versa. The fl

关键词： Benthic foraminifera Yellow Sea Cold Water Mass Holocene El Nifio Southern Oscillation East Asian Winter Monsoon

Microstructure and Mechanical Properties of Electron Beam Welded Alloy J75

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Journal of Materials Science & Technology 2014年第5期30卷 493-498页

作者： shenghu Chen Mingjiu zhao Hao Liang Lijian rong Institute of Metal Research Chinese Academy of Sciences Institute of System Engineering China Academy of Engineering and Physics

Microstructure and mechanical properties of electron beam post-weld aging treatment （PWAT） conditions. The results welded alloy J75 were studied under as-welded and showed that high-quality welds were produced by electron beam welding. Under as-welded condition, a fine dendritic structure consisting of gamma dendrite matrix and Laves phase was observed in the welds. Better mechanical properties were obtained in the weld zone than that of base metal because of the fine size of the dendritic structure. After PWAT, a discontinuous distribution of γ＇ particles existed in the dendritic structure. The presence of a γ＇ depletion zone in the dendrite core resulted in a significant degradation of mechanical properties of the weld.

关键词： Electron beam welding Alloy J75 Precipitation Mechanical properties

New analytical solution for the analysis and design of permanent magnet thrust bearings

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第8期10卷 1199-1204页

作者： Huan YANG rong-xiang zhao Shi-you YANG School of Electrical Engineering Zhejiang University Hangzhou 310027 China

On the basis of the current sheet model, a new analytical solution for permanent magnet （PM） bearings is developed. Compared with analytical methods based on the coupling energy model and the magnetic dipole model, the proposed one is more physically intuitive and convenient for engineering designers. According to the analytical model, the thrust characteristics of a novel PM thrust bearing is studied and verified by finite element analysis （FEA）. In the proposed thrust bearing configuration, the rotor is composed of stacked PM tings with alternative axial magnetization directions, and the stator with alternative radial magnetization directions while copper rings are used to separate adjacent PM rings. A prototype PM thrust bearing with the proposed configuration is designed and fabricated. The performances of the PM thrust beating are experimentally validated. It is shown that the calculation accuracy of the presented analytical solution is satisfying.

关键词： Permanent magnet (PM) Current sheet model Thrust bearing Vibration

Spatiotemporal variations of PM_(2.5) and PM_(10) concentrations between31 Chinese cities and their relationships with SO_2,NO_2,CO and O_3

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Particuology 2015年第3期13卷 141-149页

作者： Yangyang Xie Bin zhao Lin Zhang rong Luo Department of Building Science School of ArchitectureTsinghua University Department of Electronic Engineering Tsinghua University

The variations of mass concentrations of PM2.5, PMl0, SO2, NO2, CO, and 03 in 31 Chinese provincial capital cities were analyzed based on data from 286 monitoring sites obtained between March 22, 2013 and March 31,2014. By comparing the pollutant concentrations over this length of time, the characteristics of the monthly variations of mass concentrations of air pollutants were determined. We used the Pearson correlation coefficient to establish the relationship between PM2.5, PM10, and the gas pollutants. The results revealed significant differences in the concentration levels of air pollutants and in the variations between the different cities. The Pearson correlation coefficients between PMs and NO2 and SO2 were either high or moderate （PM2.s with NO2： r = 0.256-0.688, mean r = 0,498：PM10 with NO2： r = 0.169-0.713, mean r=0.493; PM2.5 with SO2： r=0.232-0.693, mean r=0.449; PM10 with SO2： r=0.131-0.669, mean r = 0.403）. The correlation between PMs and CO was diverse （PM2.5： r = 0.156-0.721, mean r = 0.437; PMl0： r= 0.06-0.67, mean r= 0.380）. The correlation between PMs and 03 was either weak or uncorrelated （PM2.s： r= -0,35 to 0.089, mean r= -0.164; PM10： r= -0.279 to 0.078, mean r= -0.127）, except in Haikou （PM2.5： r=0.500; PM10： r=0,509）.

关键词： PM2.5PM40 Atmospheric air pollutantIndoor environmentOutdoor environment

A Convenient Synthesis of Diacyl Selenides by Selenium Transfer Reaction of Primary Selenoamides

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Chinese Chemical Letters 2001年第10期12卷 873-874页

作者： Hua rong zhao Xin Jian zhao Xian HUANG Department of Chemistry Zhejiang UniversityHangzhou 310027 Zhejiang Institute of Calibaration and Testing for Technical Superision Hangzhou 310013

As a selenium transfer reagent, arylselenoamides react with acyl chlorides in chloroform to give diacyl selenides conveniently in good yield.

关键词： diacyl selenides selenium transfer reaction

Generating colorful carrot germplasm through metabolic engineering of betalains pigments

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Horticulture Research 2023年第4期10卷 63-70页

作者： Yuan-Jie Deng Ao-Qi Duan Hui Liu Ya-Hui Wang rong-rong Zhang Zhi-sheng Xu Ai-sheng Xiong National Key Laboratory of Crop Genetics and Germplasm Enhancement and Utilization Ministry of Agriculture and Rural Affairs Key Laboratory of Biology and Germplasm Enhancement of Horticultural Crops in East ChinaCollege of HorticultureNanjing Agricultural University1 WeigangNanjing 210095China

Betalains are tyrosine-derived plant pigments exclusively found in the Caryophyllales order and some higher fungi and generally classified into two groups:red-violet betacyanins and yellow-orange *** attract great scientific and economic interest because of their relatively simple biosynthesis pathway,attractive colors and health-promoting ***-expressing two core genes BvCYP76AD1 and BvDODA1 with or without a glycosyltransferase gene MjcDOPA5GT allowed the engineering of carrot(an important taproot vegetable)to produce a palette of unique *** highest total betalains content,943.2μg·g^(−1) DW,was obtained in carrot taproot transformed with p35S:RUBY which produces all of the necessary enzymes for betalains ***-specific production of betalains slightly relieved tyrosine consumption revealing the possible bottleneck in betalains ***,a unique volcano-like phenotype in carrot taproot cross-section was created by vascular cambium-specific production of *** betalains-fortified carrot in this study is thus anticipated to be used as functional vegetable and colorful carrot germplasm in breeding to promote health.

关键词： germplasm breeding orange

Creep-Resistant Covalent Adaptable Networks with Excellent SelfHealing and Reprocessing Performance via Phase-Locked Dynamic Covalent Benzopyrazole-Urea Bonds

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Chinese Journal of Polymer Science 2024年第10期42卷 1545-1556,I0013页

作者： Miao Xie Xiao-rong Wang Zhan-Hua Wang He-sheng Xia State Key Laboratory of Polymer Materials Engineering Polymer Research InstituteSichuan UniversityChengdu610065China School of Petrochemical Engineering Liaoning Petrochemical UniversityFushun113001China

Covalent adaptive networks(CANs)are capable of undergoing segment rearrangement after being heated,which endows the materials with excellent self-healing and reprocessing performance,providing an efficient solution to the environment pollution caused by the plastic *** main challenge remains in developing CANs with both excellent reprocessing performance and creep-resistance *** this study,a series of CANs containing dynamic covalent benzopyrazole-urea bonds were developed based on the addition reaction between benzopyrazole and isocyanate *** calculation confirmed that relatively low dissociation energy is obtained through undergoing a five-member ring transition state,confirming excellent dynamic property of the benzopyrazole-urea *** verified by the FTIR results,this nice dynamic property can be well maintained after incorporating the benzopyrazole-urea bonds into polymer *** self-healing and reprocessing performance is observed by the 3-ABP/PDMS elastomers owing to the dynamic benzopyrazole-urea *** separation induced by the aggregation of the hard segments locked the benzopyrazole-urea bonds,which also makes the elastomers display excellent creep-resistance *** hard phase locking strategy provides an efficient approach to design CANs materials with both excellent reprocessing and creep-resistance performance.

关键词： Covalent adaptive networks Self-healing polymer Dynamic covalent bond