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Distribution and geochemical significance of alkylbenzenes for crude oil with different depositional environments and thermal maturities

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Petroleum Science 2024年第2期21卷 777-790页

作者： Bing-Kun Meng Dao-Fu Song Yuan Chen sheng-bao Shi School of Petroleum Engineering and Environmental Engineering Yan'an UniversityYan'an716000ShaanxiChina State Key Laboratory of Petroleum Resources and Prospecting College of GeosciencesChina University of PetroleumBeijing102249China

A total of 45 alkylbenzenes were detected and identified in crude oils with different depositional environments and thermal maturities from the Tarim Basin,Beibuwan Basin,and Songliao Basin using comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry(GC×GCTOFMS).By analyzing the distribution characteristics of C0-C5alkylbenzenes,it is found that the content of some alkylbenzenes varies greatly in crude *** on the distribution characteristics of 1,2,4,5-tetramethylbenzene(Te MB)and 1,2,3,4-Te MB,the ratio of 1,2,4,5-Te MB to 1,2,3,4-Te MB is proposed to indicate the organic matter origin and depositional environment of ancient *** samples originated mainly from lower hydrobiont,algae,bacteria and source rocks deposited under reducing/anoxic conditions have low 1,2,4,5-/1,2,3,4-Te MB values(less than 0.6),while oil samples originated mainly from terrestrial higher plants and source rocks deposited under oxic/sub-oxic conditions have higher 1,2,4,5-/1,2,3,4-Te MB values(greater than 1.0).The significant difference of 1,2,4,5-/1,2,3,4-Te MB values is controlled by 1,2,4,5-Te MB content.1,2,4,5-Te MB content in oils derived from source rocks deposited in oxidized sedimentary environment(greater than 1.0 mg/g whole oil)is higher than that in oils from source rocks deposited in reduced sedimentary environment(less than 1.0 mg/g whole oil).1,2,4,5-/1,2,3,4-Te MB ratio might not or slightly be affected by evaporative fractionation,biodegradation and thermal maturity.1,2,4,5-/1,2,3,4-Te MB ratio and 1,2,4,5-Te MB content can be used as supplementary parameter for the identification of sedimentary environment and organic matter *** should be noted that compared to the identification of organic matter sources,the 1,2,4,5-/1,2,3,4-Te MB parameter is more effective in identifying sedimentary environments.

关键词： 1 2 4 5-Tetramethylbenzene GC×GC-TOFMS Organic matter origin Depositional environment

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Effects of long term aging on microstructure and properties of a tungsten bearing heat resistant alloy

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Journal of Iron and Steel Research International 2020年第4期27卷 477-487页

作者： Han-sheng bao Gang Yang Zheng-zong Chen Zheng-dong Liu Institute for Special Steels Central Iron and Steel Research InstituteBeijing 100081China

The effects of long-term aging at 700 and 750℃ on microstructure and mechanical properties of a new developed tungsten bearing heat-resistant alloy used for advanced ultra-supercritical power plant was investigated both experimentally and *** results showed that the mechanical properties maintained excellent stability after long-term aging at 700℃ for 10,000h,while the impact absorbing energy decreased sharply after 1000-h aging and then kept constant till 10,*** main precipitates after long-term aging at 700 and 750℃ were M23C6,MC and homogeneous γ′-*** mass fraction of M23C6 carbides increased with increasing aging time,and M23C6 carbides precipitated in shape of chains and lamellas on grain *** slight decrease in MC carbides during aging may be due to degradation *** weight fraction of γ′-phase increased with the aging time,and then changed little after 5000h;γ′-phase exhibited excellent microstructure stability and low coarsening rate during long-term aging at 700℃.However,the coarsening rate of γ′-phase was much higher at 750℃.

关键词： Tungsten Long-term aging Heat-resistant alloy gama′-phase Coarsening rate

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Evolution of precipitates in Ni-Co-Cr-W-Mo superalloys with different tungsten contents

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Rare Metals 2020年第6期39卷 716-724页

作者： Han-sheng bao Zhi-Hua Gong Zheng-Zong Chen Gang Yang Institute for Special Steels Central Iron and Steel Research InstituteBeijing 100081China School of Materials and Metallurgy Inner Mongolia University of Science and TechnologyBaotou 014010China

The Ni-Co-Cr-W-Mo system is critical for the design of nickel-based *** system stabilizes different topologically close-packed(TCP)phases in many commercially superalloys with high W and Mo *** electron microscopy(SEM),transmission electron microscopy(TEM)and thermodynamic calculations were applied to investigate the thermodynamics of the precipitates in two different W-contained Ni-Co-Cr-WMo superalloys(Alloy 1 and Alloy 2).Computational thermodynamics verifies the experimental observation of theμphase formation as a function of temperature and alloy chemistry,but the kinetics for the precipitation of the M6 C phase do not agree with the experimental *** major precipitates of Alloy 1 at temperatures of700℃and 750℃during long-time exposure are M23 C6,γ′phase and MC;for Alloy 2,they are M23 C6,γ′phase,MC,M6 C andμphase.W addition is found to promote the precipitation of M6 C andμphase during exposure.M6 C has higher W and lower Ni content thanμphase,whereas M6 C is an unstable phase that would transform into M12 C after 5000-h exposure at 750℃.A great quantity of needle-likeμphases precipitated after exposure at 750℃for5000 h,which have no effect on the impact properties of Alloy 2.

关键词： Nickel-based superalloys M6C μphase Long-time exposure M12C

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From amides to urea derivatives or carbamates with chemospecific C–C bond cleavage at room temperature

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Organic Chemistry Frontiers 2022年第5期9卷 1354-1363页

作者： Cong Lv Dan Liu Tegshi Muschin Chaolumen Bai Agula bao Yong-sheng bao College of Chemistry and Environmental Science Inner Mongolia Key Laboratory of Green catalysisInner Mongolia Normal UniversityHohhot010022China

Ureas and carbamates are common motifs in pharmaceuticals,agrochemicals,biologically active com-pounds and organocatalysis ***,we report a significant advancement in this area and present a general method for copper-catalyzed chemospecific C–C bond cleavage of amides to syn-thesize urea derivatives and carbamates at room temperature.

关键词： temperature cleavage bond

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Effect of Mo and cold forging deformation on strength and ductility of cobalt-based alloy L605

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Journal of Iron and Steel Research International 2024年第7期31卷 1811-1823页

作者： Zhong-lin Wang Zhi-hua Gong Quan Li Han-sheng bao School of Materials and Metallurgy Inner Mongolia University of Science and TechnologyBaotou 014017Inner MongoliaChina Institute of Special Steels Central Iron and Steel Research Institute Co.Ltd.Beijing 100081China

Mo element was added to cobalt-based alloy L605,and cold forging deformation was *** effects of the addition and cold forging deformation on the microstructure and mechanical properties of the alloy were studied by thermodynamic calculation,electron backscatter diffraction,transmission electron microscopy,and X-ray *** stacking fault energy(SFE)of the alloy decreased after the addition,and the formation of stacking faults and intersections were promoted to improve the strength and *** tensile strength of the alloy with Mo increased from 1190 to 1702 MPa after 24%cold deformation,producing significant work *** strengthening mechanism is strain-induced martensitic transformation(SIMT)and deformation *** alloy,combined with Mo and after 24%deformation,had both high strength and ductility in comparison with the original cobalt-based alloy *** is attributed to the lower SFE which caused the increase in stacking fault *** the tensile process,theε-hcp phase was easily generated at the stacking fault to reduce the stress concentration and increase the *** SIMT by adjusting the density of stacking faults can improve the mechanical properties of cobalt-based ***ε-hcp phase,the interaction between deformation twins and dislocations,and the interaction between e-hcp phases during cold forging deformation caused local stress concentration,lowering ductility and toughness.

关键词： Cobalt-based alloy-Stacking fault energy Strain-induced martensitic transformation Deformation twin Cold forging deformation

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2T-PERIODIC SOLUTION FOR m ORDER NEUTRAL TYPEDIFFERENTIAL EQUATIONS WITH TIME DELAYS

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Applied Mathematics and Mechanics(English Edition) 2002年第1期23卷 100-106页

作者： ZHANG bao-sheng(张保生) ZHU Guang-hui(朱光辉) Department of Mathematics Yunnan Nationalities InstituteKunming 650031 P R China Department of Mathematics Yunnan Nationalities InstituteKunming 650031 P R China

Periodic solution of m order linear neutral equations with constant coefficient and time delays was studied. Existence and uniqueness of 2 T-periodic solutions for the equation were discussed by using the method of Fourier series. Some new necessary and sufficient conditions of existence and uniqueness of 2 T-periodic solutions for the equation are obtained. The main result is used widely. It contains results in some correlation paper for its special case, improves and extends the main results in them. Existence of periodic solution for the equation in larger number of particular case can be checked by using the result, but cannot be checked in another paper. In other words, the main result in this paper is most generalized for (1) the better result cannot be found by using the same method.

关键词： neutral type equation 2T-periodic solution Fourier series

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Accuracy analysis of omnidirectional mobile manipulator with mecanum wheels

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Advances in Manufacturing 2016年第4期4卷 363-370页

作者： Shuai Guo Yi Jin sheng bao Feng-Feng Xi Shanghai Key Laboratory of Intelligent Manufacturing andRobotics Shanghai University Shanghai People's Republicof China Department of Aerospace Engineering Ryerson UniversityToronto Canada

This article is based on the omnidirectional mobile manipulator with mecanum wheels built at Shanghai University. The article aims to find and analyze the parameters of kinematic equation of the omnidirectional system which affects its motion accuracy. The method of solving the parameter errors involves three phases. The first step is equation operation to achieve the equation of relative errors. The second step is to obtain the displacement errors of the system via experiment and combine the error results with kinematic equation deduction to solve the geometric parameter errors in two methods. The third step is to verify its validity via comparing experiments. We can then revise its kinematics equation afterwards.

关键词： Mecanum wheel Displacement error MonteCarlo analysis Interval analysis

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Multiple temporal scale relationships of bankfull discharge with streamflow and sediment transport in the Yellow River in China

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International Journal of Sediment Research 2013年第4期28卷 496-510页

作者： Yan-yan ZHANG De-yu ZHONG bao-sheng WU State Key Laboratory of Hydroscience and Engineering Tsinghua University Pearl River Hydraulic Research Institute Pearl River Water Resources Commission

This paper presents a study on the characteristics of multiple time scales of bankfull discharge and its delayed response to changes of tlow conditions using continuous wavelet analysis for data from selected hydrologieal stations in the Yellow River *** showed that bankfull discharge series had one or two dominant lime *** example,the Huayuankou station in the lower reach of the Yellow River had two dominant time scales of 19 20 years and 5 6 *** dominant time seales of the bankfull discharge series were generally consistent with the dominant time scales of water discharge and sediment concentration series,indicating thai the channel morphology inherits the characteristics of the hydrologieal system in terms of multiple time *** addition,the wavelet coefficients of the bankfull discharge series had a phase difference in relation to those of the sediment concentration series,with a delay time that varied from 3 to 16 years at different *** delay time or relaxation lime is a result of the delayed response of bankfull discharge to How conditions,which was significant for channel adjustments in response lo changes of tlow *** findings of the multiple lime scales and the delayed response are of importance for further study of channel morphology of fluvial systems.

关键词： Multiple time scales wavelet analysis bankfull discharge river morphology fluvial processes Yellow River

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Moving target defense:state of the art and characteristics

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Frontiers of Information Technology & Electronic Engineering 2016年第11期17卷 1122-1153页

作者： Gui-lin CAI bao-sheng WANG Wei HU Tian-zuo WANG College of Computer National University of Defense Technology

Moving target defense(MTD) has emerged as one of the game-changing themes to alter the asymmetric situation between attacks and defenses in cyber-security. Numerous related works involving several facets of MTD have been published. However, comprehensive analyses and research on MTD are still absent. In this paper, we present a survey on MTD technologies to scientifically and systematically introduce, categorize, and summarize the existing research works in this field. First, a new security model is introduced to describe the changes in the traditional defense paradigm and security model caused by the introduction of MTD. A function-and-movement model is provided to give a panoramic overview on different perspectives for understanding the existing MTD research works. Then a systematic interpretation of published literature is presented to describe the state of the art of the three main areas in the MTD field, namely, MTD theory, MTD strategy, and MTD evaluation. Specifically,in the area of MTD strategy, the common characteristics shared by the MTD strategies to improve system security and effectiveness are identified and extrapolated. Thereafter, the methods to implement these characteristics are concluded. Moreover, the MTD strategies are classified into three types according to their specific goals, and the necessary and sufficient conditions of each type to create effective MTD strategies are then summarized, which are typically one or more of the aforementioned characteristics. Finally, we provide a number of observations for the future direction in this field, which can be helpful for subsequent researchers.

关键词： Moving target defense Security model Function-and-movement model Characteristics

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The relationship between international crude oil prices and China＇s refined oil prices based on a structural VAR model

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Petroleum Science 2017年第1期14卷 228-235页

作者： Song Han bao-sheng Zhang Xu Tang Ke-Qiang Guo School of Business Administration China University of Petroleum Beijing 102249 China

With the frequent fluctuations of international crude oil prices and China＇s increasing dependence on foreign oil in recent years, the volatility of international oil prices has significantly influenced China domestic refined oil price. This paper aims to investigate the transmission and feedback mechanism between international crude oil prices and China＇s refined oil prices for the time span from January 2011 to November 2015 by using the Granger causality test, vector autoregression model, impulse response function and variance decomposition methods. It is demonstrated that variation of international crude oil prices can cause China domestic refined oil price to change with a weak feedback effect. Moreover, international crude oil prices and China domestic refined oil prices are affected by their lag terms in positive and negative directions in different degrees. Besides, an international crude oil price shock has a signif- icant positive impact on domestic refined oil prices while the impulse response of the international crude oil price variable to the domestic refined oil price shock is negatively insignificant. Furthermore, international crude oil prices and domestic refined oil prices have strong historical inheri- tance. According to the variance decomposition analysis, the international crude oil price is significantly affected by its own disturbance influence, and a domestic refined oil price shock has a slight impact on international crude oil price changes. The domestic refined oil price variance is mainly caused by international crude oil price disturbance, while the domestic refined oil price is slightly affected by its own disturbance. Generally, domestic refined oil prices do not immediately respond to an international crude oil price change, that is, there is a time lag.

关键词： International crude oil prices China's refinedoil prices VAR model Granger causality - Impulseresponse Variance decomposition

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