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An introduction to the novel vacuum plume effects experimental system

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Science China(Technological Sciences) 2016年第6期59卷 953-960页

作者： CAI Guo biao LING Gui Long he bi Jiao School of Astronautics Beihang University

This paper introduces a newly developed vacuum Plume effects Experimental System(PES) used for plume effect tests of rocket engines and vacuum heat tests of satellites. The design level, manufacturing technique, and testing capabilities of the PES have reached a highly advanced level at home and abroad. The PES mainly consists of a vacuum chamber, vacuum acquisition system, nitrogen system, helium system, and parameter measurement system. A breakthrough was obtained on the Large Scale Cryo-Pumping System, which was based on a combined liquid nitrogen and liquid helium heat sink. An internal cryopump with a limiting temperature of 4.2 K and an efficient absorption area of 305 m2 was developed. The absorption capability of the cryopump was above 7×107 L/s. Vacuum plume tests were performed in the temperature ranges of ambient temperature, liquid nitrogen, and liquid helium. The experimental results showed that the plume test capability of PES is higher than that of similar foreign equipment STG and CHAFF-4. For 2 g/s and 117 N rocket engines, the dynamic vacuum degree of environment was 8.0×10?4 Pa(approximately 137 km height) and 1.1×10?2 Pa(approximately 106 km height), respectively.

关键词： vacuum plume effect liquid nitrogen heat sink liquid helium heat sink plume absorption pump

VLW equation of state of detonation products

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Science China Chemistry 2009年第5期52卷 605-608页

作者： WU Xiong LONG XinPing he bi JIANG XiaoHua Xi’an Modern Chemistry Research Institute Xi’an 710065China China Academy of Engineering Physics Mianyang 621900China Institute of Chemical Materials CAEPMianyang 621900China

Based on the virial theory, we proposed VLW equation of state of detonation products (VLW EOS). Its basic theory and applications were described. The distinct features of the VLW EOS were:First, the detonation performance of the new high energy density materials could be predicted more reliably. Second, it had extensive application. The detonation parameters of both the condensed high energy density materials and the gaseous fuel air explosives could be calculated. Moreover, combustion performance of propellants could also be precisely calculated. The calculation results were satisfactory.

关键词： virial coefficients energetic materials equation of state detonation

Effective source rock selection and oil–source correlation in the Western Slope of the northern Songliao Basin,China

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Petroleum Science 2021年第2期18卷 398-415页

作者： he bi Peng Li Yun Jiang Jing-Jing Fan Xiao-Yue Chen Research Institute of Petroleum Exploration and Development PetroChinaBeijing100083China Petroleum Exploration and Production Research Institute SINOPECBeijing100083China China National Oil and Gas Exploration and Development Co.Ltd. Beijing100034China

This study considers the Upper Cretaceous Qingshankou Formation,Yaojia Formation,and the first member of the Nenjiang Formation in the Western Slope of the northern Songliao *** mudstone with high abundances of organic matter of Gulong and Qijia sags are considered to be significant source rocks in the study *** evaluate their development characteristics,differences and effectiveness,geochemical parameters are ***-dimensional basin modeling and hydrocarbon evolution are also applied to discuss the effectiveness of source *** the biomarker characteristics,the source–source,oil–oil,and oil–source correlations are assessed and the sources of crude oils in different rock units are *** on the results,Gulong and Qijia source rocks have different organic matter primarily detrived from mixed sources and plankton,*** source rock has higher thermal evolution degree than Qijia source *** biomarker parameters of the source rocks are compared with 31 crude oil *** studied crude oils can be divided into two *** oil–source correlations show that group I oils from Qing II–III,Yao I,and Yao II–III members were probably derived from Gulong source rock and that only group II oils from Nen I member were derived from Qijia source rock.

关键词： Songliao basin Western slope Source rock distinction Crude oils biomarker Oil-source correlation

Differences in and factors controlling organic matter enrichment in the Ziliujing Formation shale in the Sichuan Basin

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Petroleum Science 2024年第1期21卷 77-86页

作者： Peng Li Zhong-Bao Liu he bi Tao Jiang Rui-Kang bian Peng-Wei Wang Xiao-Yu Shang State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Efficient Development Beijing102206China Key Laboratory of Shale Oil/Gas Exploration and Production Technology SINOPECBeijing102206China Petroleum Exploration and Production Research Institute SINOPECBeijing102206China Research Institute of Petroleum Exploration and Development PetroChinaBeijing100083China Chinese Academy of Geological Sciences Beijing100037China No.4 Oil Production Plant in Daqing Oilfield Co Ltd. Daqing163511HeilongjiangChina

Lacustrine shale oil and gas are important fields for unconventional exploration and development in China,and organic-rich shale deposition lays down the critical foundation for hydrocarbon *** are two sets of shale,the Dongyuemiao and Da’anzhai Members,in the Ziliujing Formation in the Sichuan *** identify the differential enrichment characteristics of organic matter and clarify its controlling factors,geochemical analyses of organic and inorganic geochemical analyses were *** results showed that the total organic carbon content of the Dongyuemiao shale(1.36%)is slightly higher than that of the Da’anzhai shale(0.95%).The enrichment of organic matter in the two shales resulted from the comprehensive controls of paleoproductivity,paleoenvironment,and terrigenous input,but different factors have different *** addition,driven by climate,the change in the sulfate concentration in the bottom water further led to the different intensities of bacterial sulfate reduction in early *** made a great difference regarding organic matter accumulation in the two *** general,climate may have played a dominant role in organic matter enrichment in the two sets of shale.

关键词： Lacustrine shale Ziliujing Formation Sichuan Basin Enrichment mechanism of organic matter

Extraction of pipeline defect feature based on variational mode and optimal singular value decomposition

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Petroleum Science 2023年第2期20卷 1200-1216页

作者： Min Zhang Yan-Bao Guo Zheng Zhang Ren-bi he De-Guo Wang Jin-Zhong Chen Tie Yin College of Mechanical and Transportation Engineering China University of PetroleumBeijing102249China China Special Equipment Inspection and Research Institute Beijing100029China China Petroleum and Natural Gas Pipeline Research Institute Co.LTD LangfangHebei 065000China

Because the magnetic signal information of pipeline defects obtained by magnetic flux leakage detection contains interference signals, it is difficult to accurately extract the features. Therefore, a novel pipeline defect feature extraction method based on VMD-OSVD (variational modal decomposition - optimal singular value decomposition) is proposed to promote the signal to noise ratio (SNR) and reduce aliasing in the frequency domain. By using the VMD method, the sampled magnetic signal is decomposed, and the optimal variational mode is selected according to the rate of relative change (VMK) of Shannon entropy (SE) to reconstruct the signal. After that, SVD algorithm is used to filter the reconstructed signal again, in which the H-matrix is optimized with the phase-space matrix to enhance SNR and decrease the frequency domain aliasing. The results show that the method has excellent denoising ability for defect magnetic signals, and SNR is increased by 21.01%, 24.04%, 0.96%, 32.14%, and 20.91%, respectively. The improved method has the best denoising effect on transverse mechanical scratches, but a poor denoising effect on spiral welding position. In the frequency domain, the characteristics of different defects are varied, and their corresponding frequency responses are spiral weld corrosion > transverse mechanical cracking > girth weld > deep hole > normal pipe. The high-frequency band is the spiral weld corrosion with f1 = 153.37 Hz. The low-frequency band is normal with f2 = 1 Hz. In general, the VMD-OSVD method is able to improve the SNR of the signal and characterize different pipe defects. And it has a certain guiding significance to the application of pipeline inspection in the field of safety in the future.

关键词： VMD method VMK SVD algorithm Phase space matrix Signal characteristics Pipeline defect Reconstruct

Pore Size Distribution of a Tight Sandstone Reservoir and its Effect on Micro Pore-throat Structure: A Case Study of the Chang 7 Member of the Xin’anbian Block, Ordos Basin, China

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Acta Geologica Sinica(English Edition) 2020年第2期94卷 219-232页

作者： LI Peng JIA Chengzao JIN Zhijun LIU Quanyou bi heZheNG Min WU Songtao HUANG Zhenkai State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development Beijing 100083China Petroleum Exploration and Production Research Ins Institute SINOPECBeijing 100083China China National Petroleum Corporation.Beijing 100724 China Research Institute of Petroleum Exploration and Development PetroChinaBeijing 100083China

Pore distribution and micro pore-throat structure characteristics are significant for tight oil reservoir evaluation, but their relationship remains unclear. This paper selects the tight sandstone reservoir of the Chang 7 member of the Xin’anbian Block in the Ordos Basin as the research object and analyzes the pore size distribution and micro pore-throat structure using field emission scanning electron microscopy(FE-SEM), high-pressure mercury injection(HPMI), highpressure mercury injection, and nuclear magnetic resonance(NMR) analyses. The study finds that:(1) Based on the pore size distribution, the tight sandstone reservoir is characterized by three main patterns with different peak amplitudes. The former peak corresponds to the nanopore scale, and the latter peak corresponds to the micropore scale. Then, the tight sandstone reservoir is categorized into three types: type 1 reservoir contains more nanopores with a nanopore-to-micropore volume ratio of 82:18;type 2 reservoir has a nanopore-to-micropore volume ratio of 47:53;and type 3 reservoir contains more micropores with a nanopore-to-micropore volume ratio of 35:65.(2) Affected by the pore size distribution, the throat radius distributions of different reservoir types are notably offset. The type 1 reservoir throat radius distribution curve is weakly unimodal, with a relatively dispersed distribution and peak ranging from 0.01 μm to 0.025 μm. The type 2 reservoir’s throat radius distribution curve is single-peaked with a wide distribution range and peak from 0.1 μm to 0.25 μm. The type 3 reservoir’s throat radius distribution curve is single-peaked with a relatively narrow distribution and peak from 0.1 μm to 0.25 μm. With increasing micropore volume, pore-throat structure characteristics gradually improve.(3) The correlation between micropore permeability and porosity exceeds that of nanopores, indicating that the development of micropores notably influences the seepage capacity. In the type 1 reservoir, only

关键词： tight sandstone reservoir pore size distribution pore-throat structure Ordos Basin Chang 7 member

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直接模拟蒙特卡罗羽流模拟的两相作用模型

推进技术 2011年第2期32卷 214-219页

作者：何小英贺碧蛟蔡国飙北京航空航天大学宇航学院北京100191

为了数值模拟包含气体分子和凝相颗粒的两相羽流场,使用自主开发的羽流计算软件(PWS)对两相作用模型进行研究。计算均匀气流对颗粒的加速过程,结果与理论解一致,证明气体分子对颗粒的单向作用模型合理。计算气体分子在颗粒表面的反射时... 详细信息

为了数值模拟包含气体分子和凝相颗粒的两相羽流场,使用自主开发的羽流计算软件(PWS)对两相作用模型进行研究。计算均匀气流对颗粒的加速过程,结果与理论解一致,证明气体分子对颗粒的单向作用模型合理。计算气体分子在颗粒表面的反射时,将全局坐标系转换到颗粒坐标系确定其法线,再转换到法线坐标系进行镜面反射或漫反射。将这种间接法与使用反射向量的分布函数的直接法进行了对比。对同一个气体分子在颗粒表面的反射进行1×106次数值试验,两种方法所得镜面反射的速度向量均符合空间均匀分布,漫反射的速度向量分布相互一致。使用两种方法模拟150N液体火箭发动机的两相羽流场,所得气相羽流场几乎相同,间接法计算效率较高。液滴颗粒对气流场的影响主要集中在轴线附近,与无液滴的气流场相比,有液滴时会使气流温度升高、压强增大、马赫数减小。

关键词：直接模拟蒙特卡罗两相羽流场气体-表面反射漫反射镜面反射

The Status Quo and Prospect of the Study on Ideological-Political Construction in Middle School English Curriculum

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Journal of Literature and Art Studies 2023年第2期13卷 95-99页

作者： he bi-lang LI Ju-yuan School of Foreign Studies Guangzhou UniversityGuangzhouChina

Ideological-political construction in English curriculum is to integrate outlook on the world,outlook on life,outlook on values,*** English language teaching and *** recent years,studies on ideological-political construction in middle school English curriculum have made some progress,with an emphasis on its significance and the strategies for its ***,there is still room for expansion in the research methods,research contents,and research perspectives.

关键词： ideological-political construction in curriculum middle school English status quo prospects

高等教育财政模式与高等教育体制模式关系研究——兼论政府与高校间的经济关系

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清华大学教育研究 2008年第4期29卷 64-68,75页

作者：毕鹤霞华中科技大学教育科学研究院湖北武汉430074

本文从高等教育财政模式与高等教育体制模式的机理出发,解析了理论形态下高等教育财政模式与高等教育体制模式的内涵与相互关系,构建了S-0结构机理模型,模拟了高等教育财政模式对高等教育体制模式的影响趋势,最后指出研究结论,并给出政... 详细信息

本文从高等教育财政模式与高等教育体制模式的机理出发,解析了理论形态下高等教育财政模式与高等教育体制模式的内涵与相互关系,构建了S-0结构机理模型,模拟了高等教育财政模式对高等教育体制模式的影响趋势,最后指出研究结论,并给出政策建议。

关键词：高等教育财政模式高等教育体制模式