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Genetic types and geochemicai characteristics of natural gases in the Jiyang Depression,China

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Petroleum Science 2015年第1期12卷 81-95页

作者： wen-Tao li Yang Gao Chun-Yan Geng School of Energy Resources China University of Geosciences Geoscience Research Institute Shengli Oilfield Company SINOPEC

Natural gases were widely distributed in the Jiyang Depression with complicated component composition, and it is difficult to identify their genesis. Based on investigation of gas composition, carbon isotope ratios, light hydrocarbon properties, as well as geological analysis, natural gases in the Jiyang Depression are classified into two types, one is organic gas and the other is abiogenic gas. Abiogenic gas is mainly magmatogenic or mantlederived CO2. Organic gases are further divided into coaltype gas, oil-type gas, and biogas according to their kero- gen types and formation mechanisms. The oil-type gases are divided into mature oil-type gas （oil-associated gas） and highly mature oil-type gas. The highly mature oil-type gases can be subdivided into oil-cracking gas and kerogen thermal degradation gas. Identification factors for each kind of hydrocarbon gas were summarized. Based on genesis analysis results, the genetic types of gases buried in different depths were discussed. Results showed that shallow gases （〈1,500 m） are mainly mature oil-type gases, biogas, or secondary gases. Secondary gases are rich in methane because of chromatographic separation during migration and secondary biodegradation. Secondary biodegradation leads to richness of heavy carbon isotope ratios in methane and propane. Genesis of middle depth gases （1,500-3,500 m） is dominated by mature oil-type *** gases （3,500-5,500 m） are mainly kerogen thermal degradation gas, oil-cracking gas, and coal-type gas.

关键词： Genetic types Natural gases Jiyang Depression light hydrocarbon properties Carbon isotope ratios Identification factors

Interplanetary transfer optimization using cost function with variable coecients

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Astrodynamics 2019年第2期3卷 173-188页

作者： xiangyu li dong Qiao Hongbo Chen School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Key Laboratory of Dynamics and Control of Flight Vehicle Ministry of EducationBeijing 100081China China Academy of Launch Vchicle T'echnology Beijing 100076China

In this paper,the optimal interplanetary transfer including planetary escape and capture phases is investigated in the heliocentric *** on primer vector theory,a modi ed cost function with variable coecients is developed to re ect the gravitational e ect more *** necessary conditions as well as the transversality conditions of the new cost function are derived to search the optimal solution in *** introducing the initial and nal coasts,the optimal interplanetary transfer is extended to the time-free ***,the proposed method is applied to the Earth-Mars and Earth-Asteroid *** with existing methods show that the proposed method can provide better transfer performances with high e*** proposed method extends the application of primer vector theory and provides a fast and accurate reference for preliminary mission design in spacecraft planetary exploration.

关键词： orbit optimization primer vector interplanetary transfer time-free

Quantitative division of succession and spatial patterns among different stand developmental stages in Changbai Mountains

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Journal of Mountain Science 2019年第9期16卷 2063-2078页

作者： GONG Zhi-wen KANG Xin-gang GU li College of Economics and Management Research Center of Resource Economics and Environment Management Northwest A8J7 University Yangling 712100 China College of Forestry Northwest A&F University Yang ling 712100 China College of Forestry Beijing Forestry University Beijing 100083 China

Broadleaf-Korean pine forests exhibit high species richness and distinctive species composition, which are currently becoming more dominant among natural forests in Changbai Mountains of northeastern China. Understanding the ecological process of restored vegetation is quite important for ecosystem reconstruction. Distinguishing stand development stages and analyzing the dynamic spatial patterns could provide insights into significant community coexistence mechanisms. In the present study, eight permanent study areas were established according to the substituting space for time method in Changbai Mountains of north-eastern China. The optimal division method was used to quantify the successional series into different stand development stages, and the point pattern analysis method(L(r) function) was used to analyse the dynamic changes in spatial patterns and interspecific associations. Our results suggested that:(1) The stand development process was divided into five stages: the first three stages were poplar-birch secondary forests in different stages of recovery, the fourth stage was thespruce-fir mixed forest, and the last stage was the primary broadleaf-Korean pine forest;(2) The spatial pattern showed an aggregated distribution at a small scale and changed to a random distribution as the scale increased in poplar-birch secondary forests, but the spatial pattern appeared to be randomly distributed in spruce-fir mixed forest and broadleafKorean pine forest;(3) The interspecific associations between pioneer species and climax species changed from negative to positive among the different stand stages, and environmental resources were shared among these species. Interspecific differences in shade tolerance among the tree species were key determinants of forest dynamics and structure. Our study is vital to the understanding of the forest development;thus, the spatial change features should receive greater attention when forest management is being planned and restoratio

关键词： Dynamic spatial patterns Interspecific association Optimal division method Stand developmental stages Space for time substitution

Risk-based security-constrained economic dispatch in power systems

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Journal of Modern Power Systems and Clean Energy 2013年第2期1卷 142-149页

作者： Qin WANG Aimin YANG Fushuan wen Jihong li Iowa State University AmesIA 50011-2151USA A.YANGSouth China University of TechnologyGuangzhou 510640China Zhejiang University Hangzhou 310027China Zhejiang Electric Power Corporation Hangzhou 310007China

Based on a new perspective in coordinating with the traditional"N-1"criteria and system risk,a real-time electricity market model is presented,in which the system risk is employed to model the system’s overall security *** new model is called the risk-based security-constrained economic dispatch(RB-SCED).Relative to the securityconstrained economic dispatch(SCED)used in the power industry today,the RB-SCED finds more secure and economic operating *** does this by obtaining solutions that achieve a better balance between post-contingency flows on individual branches and the overall system *** method exploits the fact that,in a SCED solution,some postcontingency branch flows which exceed their limits impose little risk while other post-contingency branch flows which are within their limits impose significant *** RB-SCED softens constraints for the former and hardens constraints for the latter,thus achieving simultaneous improvement in both security and *** this work,the basic concept and the mathematical formulation of the RB-SCED model are systematically *** results on a 9-bus system and the ISO New England actual system have demonstrated the advantages of RB-SCED over SCED.

关键词： Economic dispatch Security-constrained economic dispatch(SCED) Risk-based securityconstrained economic dispatch(RB-SCED) Contingency Power system

A Preconditioned Conjugate Gradient Method with Active Set Strategy for1-Regularized Least Squares

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Journal of the Operations Research Society of China 2018年第4期6卷 571-585页

作者： Wan-You Cheng dong-Hui li College of Computer Dongguan University of TechnologyDongguan 523000GuangdongChina School of Mathematical Sciences South China Normal UniversityGuangzhou 510631China

In the paper,we consider the l_(1)-regularized least square problem which has been intensively involved in the fields of signal processing,compressive sensing,linear inverse problems and statistical *** considered problem has been proved recently to be equivalent to a nonnegatively constrained quadratic programming(QP).In this paper,we use a recently developed active conjugate gradient method to solve the resulting QP *** improve the algorithm’s performance,we design a subspace exact steplength as well as a precondition *** performance comparisons illustrate that the proposed algorithm is competitive and even performs little better than several state-of-the-art algorithms.

关键词： Compressed sensing l_(1)-Regularized optimization Conjugate gradient method Precondition

Development and calibration of the Moon-based EUV camera for Chang'e-3

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Research in Astronomy and Astrophysics 2014年第12期14卷 1654-1663页

作者： Bo Chen Ke-Fei song Zhao-Hui li Qing-wen Wu Qi-liang Ni Xiao-dong Wang Jin-Jiang Xie Shi-Jie liu ling-Ping He Fei He Xiao-Guang Wang Bin Chen Hong-Ji Zhang Xiao-dong Wang Hai-Feng Wang Xin Zheng shu-lin E Yong-Cheng Wang Tao Yu liang Sun Jin-ling Wang Zhi Wang liang Yang Qing-Long Hu Ke Qiao Zhong-Su Wang Xian-Wei Yang Hai-ming Bao wen-Guang liu Zhe li Ya Chen Yang Gao Hui Sun wen-Chang Chen Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences

The process of development and calibration for the first Moon-based ex- treme ultraviolet （EUV） camera to observe Earth＇s plasmasphere is introduced and the design, test and calibration results are presented. The EUV camera is composed of a multilayer film mirror, a thin film filter, a photon-counting imaging detector, a mech- anism that can adjust the direction in two dimensions, a protective cover, an electronic unit and a thermal control unit. The center wavelength of the EUV camera is 30.2 nm with a bandwidth of 4.6nm. The field of view is 14.7° with an angular resolution of 0.08°, and the sensitivity of the camera is 0.11 count s-1 Rayleigh-1. The geomet- ric calibration, the absolute photometric calibration and the relative photometric cal- ibration are carried out under different temperatures before launch to obtain a matrix that can correct geometric distortion and a matrix for relative photometric correction, which are used for in-orbit correction of the images to ensure their accuracy.

关键词： Chang'e-3 -- EUV camera: development: calibration -- Earth's plas-masphere -- lunar exploration

Ds-echinoside A,a new triterpene glycoside derived from sea cucumber,exhibits antimetastatic activity via the inhibition of NF-κB-dependent MMP-9 and VEGF expressions

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第7期12卷 534-544页

作者： Qin ZHAO Zhi-dong liU Yong XUE Jing-feng WANG Hui li Qing-juan TANG Yu-ming WANG Ping dong Chang-hu XUE College of Food Science and Engineering Ocean University of China Qingdao 266003 China

Ds-echinoside A (DSEA),a non-sulfated triterpene glycoside,was isolated from the sea cucumber Pearsonothuria *** vitro and in vivo investigations were conducted on the effects of DSEA on tumor cell adhesion,migration,invasion,and *** this study,we found that DSEA inhibited the proliferation of human hepatocellular liver carcinoma cells Hep G2,with a half-maximal inhibitory concentration (IC50) of 2.65 μmol/L,and suppressed Hep G2 cell adhesion,migration,and invasion in a dose-dependent *** also reduced tube formation of human endothelial cells ECV-304 on matrigel in vitro and attenuated neovascularization in the chick embryo chorioallantoic membrane (CAM) assay in *** analysis revealed that DSEA significantly decreased the expression of matrix metalloproteinase-9 (MMP-9),which plays an important role in the degradation of basement membrane in tumor metastasis and *** also increased the protein expression level of tissue inhibitor of metalloproteinase-1 (TIMP-1),an important regulator of MMP-9 *** the results of Western blotting,the expressions of nuclear factor-kappa B (NF-κB) and vascular endothelial growth factor (VEGF) were found to be remarkably reduced by *** findings suggest that DSEA exhibits a significant antimetastatic activity through the specific inhibition of NF-κB-dependent MMP-9 and VEGF expressions.

关键词： Triterpene glycoside Ds-echinoside A (DSEA) Metastasis Angiogenesis Nuclear factor-κB (NF-κB) Matrix metalloproteinase-9 (MMP-9) Vascular endothelial growth factor (VEGF)

Metro-Wordle:An Interactive Visualization for Urban Text Distributions Based on Wordle

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Visual Informatics 2018年第1期2卷 50-59页

作者： Chenlu li Xiaoju dong Xiaoru Yuan Department of Computer Science and Engineering Shanghai Jiao Tong University800 Dongchuan RoadShanghaiP.R.China200240 Key Laboratory of Machine Perception(Ministry of Education) and School ofEECSPeking UniversityBeijingP.R.China100871

With the development of cities and the explosion of infonnation,vast amounts of geo-tagged textural data about Points of Interests(POIs)have been *** useful information and discovering text spatial distributions from the data are challenging and ***,the huge numbers of POIs in modem cities make it important to have efficient approaches to retrieve and choose a *** paper provides a visual design combing metro map and wordles to meet the *** this visualization,metro lines serve as the divider lines splitting the city into several subareas and the boundaries to constrain wordles within each *** wordles are generated from keywords extracted from the text about POIs(including reviews,descriptions,etc.)and embedded into the subareas based on their geographical *** generating intuitive results and providing an interactive visualization to support exploring text distribution patterns,our strategy can guide the users to explore urban spatial characteristics and retrieve a location ***,we implement a visual analysis of the restaurants data in Shanghai,China as a case study to evaluate our strategy.

关键词： Text visualization Location retrieval Urban data Metro map Word cloud

Synthesis and Evaluation of Microporous Metal Organic Frameworks for light Hydrocarbon Adsorption

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China Petroleum Processing & Petrochemical Technology 2022年第4期24卷 120-128页

作者： wen Guilin li Ying li Jianzhe li Qingrun Zhang Hongxing Xiao Anshan Tao Bin State Key Laboratory of Safety and Control for Chemicals SINOPEC Research Institute of Safety Engineering Co.Ltd.Qingdao 266101China

Five microporous MOFs were synthesized and their static adsorption properties for light hydrocarbons were experimentally investigated at 298 K and 150 *** the five MOFs,HKUST-1 and Ni(bdc)(ted)0.5 exhibited much higher uptakes of ethane and propane than PCN-250,UiO-66,and *** experiments were carried out at 298 K and atmospheric pressure on HKUST-1 and two commercially used ***-1 exhibited a much lower dynamic than static adsorption ***,HKUST-1 and the two traditional adsorbents could effectively separate binary(ethane/propane)and ternary(ethane/propane/toluene)mixtures.

关键词： light hydrocarbons metal-organic frameworks adsorption breakthrough curve adsorption selectivity