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Frontiers in Energy 2019年第3期13卷 450-463页

作者： Haizheng DANG Dingli BAO Zhiqian GAO Tao ZHANG Jun TAN Rui ZHA Jiaqi LI Ning LI Yongjiang ZHAO Bangjian ZHAO State Key Laboratory of Infrared Physics Shanghai Institute of Technical PhysicsChinese Academy of SciencesShanghai 200083China University of Chinese Academy of Sciences Beijing 100049China Institute of Fundamental and Frontier Technology Midea Refrigerator Co.Ltd.Hefei 230601China

This paper establishes a theoretical model of the single-compressor-driven (SCD) three-stage Stirlingtype pulse tube cryocooler (SPTC) and conducts experimental verifications. The main differences between the SCD type and the multi-compressor-driven (MCD) crycooler are analyzed, such as the distribution of the input acoustic power in each stage and the optimization of the operating parameters, in which both advantages and difficulties of the former are stressed. The effects of the dynamic temperatures are considered to improve the accuracy of the simulation at very low temperatures, and a specific simulation example aiming at 10 K is given in which quantitative analyses are provided. A SCD threestage SPTC is developed based on the theoretical analyses and with a total input acoustic power of 371.58 W, which reaches a no-load temperature of 8.82 K and can simultaneously achieve the cooling capacities of 2.4 W at 70 K, 0.17 W at 25 K, and 0.05 W at 10 K. The performance of the SCD three-stage SPTC is slightly poorer than that of its MCD counterpart developed in the same laboratory, but the advantages of lightweight and compactness make the former more attractive to practical applications.

关键词： single-compressor-driven three-stage Stirling-type pulse tube cryocooler theoretical modeling experimental verification

Performance study on three-stage power system of compressed air vehicle based on single-screw expander

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Science China(Technological Sciences) 2010年第8期53卷 2299-2303页

作者： HE Wei,WU YuTing ,MA ChongFang&MA GuoYuan Key Laboratory of Enhanced Heat Transfer and Energy Conservation,Ministry of Education,and Key Laboratory of Heat Transfer and Energy Conversion,Beijing Municipality,College of Environmental and Energy Engineering,Beijing University of Technology,Beijing 100124,China Key Laboratory of Enhanced Heat Transfer and Energy Conservation Ministry of Education and Key Laboratory of Heat Transfer and Energy Conversion Beijing Municipality College of Environmental and Energy Engineering Beijing University of Technology Beijing China

A new compressed-air engine system based on three-stage single screw expander was proposed to improve the performance of power *** different structure styles were presented,and the studies on the power performance and the distribution of expansion ratios between stages were carried out by programming and mathematical modeling of each *** results indicated that the best matches of expansion ratios with equal heat temperature for the air tank of pressure 30 MPa were seven-five-three for"first-stage heating"style,eight-five-three for"two-stage heating"style and five-five-four for"three-stage heating"style,*** also showed that heating up inlet air or increasing the expander efficiency might improve the power *** output power of the"two-stage heating"style is far higher than that of"first-stage heating"style and is a little lower than that of"three-stage heating"*** new system showed good structure and power performances.

关键词： compressed-air engine single screw expander three-stage power system

A three-section Algorithm of Dynamic Programming Based on three-stage Decomposition System Model for Grade Transition Trajectory Optimization Problems

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Chinese Journal of Chemical Engineering 2014年第10期22卷 1122-1130页

作者：魏宇杰江永亨黄德先 National Laboratory for Information Science and Technology Department of Automation Tsinghua University

This paper introduces a practical solving scheme of gradetransition trajectory optimization(GTTO) problems under typical certificate-checking–updating framework. Due to complicated kinetics of polymerization,differential/algebraic equations(DAEs) always cause great computational burden and system non-linearity usually makes GTTO non-convex bearing multiple optima. Therefore, coupled with the three-stage decomposition model, a three-section algorithm of dynamic programming(TSDP) is proposed based on the general iteration mechanism of iterative programming(IDP) and incorporated with adaptivegrid allocation scheme and heuristic modifications. The algorithm iteratively performs dynamic programming with heuristic modifications under constant calculation loads and adaptively allocates the valued computational resources to the regions that can further improve the optimality under the guidance of local error estimates. TSDP is finally compared with IDP and interior point method(IP) to verify its efficiency of computation.

关键词： Gradetransition trajectory optimization Adaptivegrid allocation Heuristic modifications three-section dynamic programming three-stage decomposition model

Effects of standardized three-stage rehabilitation combined with edaravone therapy on the neurotrophic state and oxidative stress injury in patients with cerebral infarction

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Journal of Hainan Medical University 2017年第24期23卷 130-133页

作者： Xin-Qun Huang Xia Zhou Department of Internal Medicine Zigong Third People's Hospital in Sichuan ProvinceZigong CitySichuan Province643020 Department of Neurology Zigong Third People's Hospital in Sichuan ProvinceZigong CitySichuan Province643020

Objective: To investigate the effects of standardized three-stage rehabilitation combined with edaravone therapy on the neurotrophic state and oxidative stress injury in patients with cerebral infarction. Methods: A total of 90 patients with acute cerebral infarction who were treated in the hospital between May 2015 and April 2017 were divided into control group (n=45) and observation group (n=45) by random number table. Control group received edaravone therapy, and observation group received standardized three-stage rehabilitation combined with edaravone therapy. The differences in neurotrophic state and oxidative stress injury were compared between the two groups before and after treatment. Results: There was no statistically significant difference in serum levels of neurotrophic indexes and oxidative stress indexes between the two groups before treatment. After treatment, serum neurotrophic indexes BDNF and NGF levels of observation group were higher than those of control group;serum oxidation indexes AOPPs, LHP and MDA levels were lower than those of control group whereas SOD, CAT and T-AOC levels were higher than those of control group. Conclusion:Standardized three-stage rehabilitation combined with edaravone therapy can effectively optimize the neurotrophic state and inhibit the oxidative stress in patients with cerebral infarction.

关键词： Cerebral infarction Standardized three-stage rehabilitation Edaravone Neurotrophic state Oxidative stress injury

Novel three-stage Structure of Erbium Doped Fiber Amplifier

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Novel Three-stage Structure of Erbium Doped Fiber Amplifier

Gas formation mechanism of marine carbonate source rocks in China

第二届仪器科学与技术国际学术研讨会

作者： Qiang Zexuan Zhang Xuliang He Sailing Zheng Wenxin and Shen LinfangCentre for Optical & Electromagnetic Research State Key Laboratory for Modern OpticalInstruments Zhejiang University China

＜正＞ Presents a novel three-stage erbium doped fiber amplifier with a very large gain and a very low noise, which utilizes a backward-propagating pump with the power of the first pump split into two parts at a ratio of e.g. 1:1 to improve the efficiency of the pump, and concludes from the Giles Model with ASE included that the numerical results are in good agreement with the experimental results.

关键词： Erbium doped fiber amplifier three-stage pump fiber communication

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Science China Earth Sciences 2005年第4期48卷 441-453页

作者： ZHAO Wenzhi1, WANG Zhaoyun1, HE Haiqing2, ZHANG Mingjie3, WANG Hongjun1, WANG Yunpeng4 & QIN Yong5 1. Research Institute of Petroleum Exploration & Development, PetroChina, Beijing 100083, China 2. PetroChina Exploration & Production, Beijing 100011, China 3. Department of Geology, Lanzhou University, Lanzhou 730000, China 4. Guangzhou Geochemical Institute, Chinese Academy of Sciences, Guangzhou 510640, China 5. China University of Mining and Technology, Xuzhou 221000, China Research Institute of Petroleum Exploration & Development PetroChinaBeijin China PetroChina Exploration & Production Beijing China Department of Geology Lanzhou University Lanzhou China Guangzhou Geochemical Institute Chinese Academy of Sciences Guangzhou China China University of Mining and Technology Xuzhou China

By breaking through the conventional ideology on the study of gas-formation mechanism of source rocks which focused on merely the characteristics of source rocks them- selves, and based on the development and distribution characteristics of marine carbonate source rocks in the medium-to-bottom parts of the Chinese superimposed sedimentary basins as well as various processes in the course of gas generation and reservoir forming, the complex hydrocarbon-generating model of carbonates is established. Such a model concerns not only the “three-stage” gas formation characteristics of carbonates, but also the gas generation process due to a thermal cracking of oil and the re-generation process of gas from heated secondary organic matters during the gas-generation and reservoir-forming course. The high-quality hy- drocarbon generating matter of marine carbonate source rocks determined a high gas-oil ratio and tended to form paleo-oil-reservoirs, representing an enrichment process of organic matters. The thermal cracking of oil in palaeo-oil-reservoirs is an important means for the effective forma- tion of gas reservoirs. The secondary organic matters in carbonate reservoirs may regenerate gas after a secondary deep burial, thus becoming an effective gas source.

关键词： carbonate, three-stage hydrocarbon generation, inhibitive effect of maturity, oil-cracking gas, second-ary asphalt gas.

A novel 3-stage structure for a low-noise, high-gain and gain-flattened L-band erbium doped fiber amplifier

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Journal of Zhejiang University Science 2004年第9期5卷 1130-1134页

作者：强则煊何赛灵张徐亮沈林放 CenterforOpticalandElectromagneticResearch StateKeyLaboratoryofModernOpticalInstrumentationJointLaboratoryofOpticalCommunicationsZhejiangUniversityHangzhou310027China

The configuration of the novel three-stage L-band erbium-doped fiber amplifier with very large and flat gain and very low noise figure presented in this paper uses the forward ASE (amplified spontaneous emission) from the first section of the EDF (erbium-doped fiber) and the backward ASE from the third section of the EDF (both serve as the secondary pump sources of energy) to pump the second EDF. To improve the pump efficiency, the power of the pump is split into two parts (with a ratio of e.g. 2:7). The characteristics of this L-band EDFA are studied on the basis of the Giles Model with ASE.

关键词： Erbium doped fiber amplifier three-stage Pump L-band Fiber optical communication

The hydrocarbon generation mechanism and the threestage type model of hydrocarbon generation for carbonate source rocks

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Science China Earth Sciences 1997年第3期40卷 232-238页

作者：王兆云程克明 Research Institute of Petroleum Exploration and Development Beijing 100083 China

The diagenetic mechanism and process of carbonate rocks, which is different to that of clastic rocks, decides the existence of different existing state organic matters in carbonate rocks. This has been verified by both the microscopic observation of organic petrology and the analysis of organic geochemistry of many samples. Based on the hydrous pyrolysis simulation experiment of the low-mature carbonate rocks, the contrasting study on the yield and their geochemistry characteristics of different existing state soluble organic matters of a series of various maturity samples shows that the different existing state organic matters make different contributions to hydrocarbon generation during every evolution state. So that, the hydrocarbon generation process of carbonate rocks can be summarized as the following three stages; the first is the direct degradation of biogenic bitumen macromolecules during the immature stage, the second is the thermal degradation of a large amount of kerogen at the mature stage, the last stage is the expulsion or release of inclusion organic matter owing to the increased thermal expansion pressure during the high evolution stage.

关键词： carbonate rocks existing state of organic matter hydrocarbon generation mechanism hydrocarbon generation model of three-stage type.

The importance of “first-blood circulation stage”, a new insight into the pathogenesis of clinical manifestations of preeclampsia

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Advances in Bioscience and Biotechnology 2012年第7期3卷 945-950页

作者： Lucijan Mohorovic Vladimir Micovic Department of Environmental Medicine University of Rijeka School of Medicine Rijeka Croatia

The tested hypothesis points out that exposure to environmental toxic substances originating from coal or other fossil fuels burning is the most decisive for the impacts of the metabolic synergy of nitrogen oxides as oxidants that cause hemoglobin oxidation to methemoglobin, and sulphur dioxide metabolites as inhibitors of antioxidants, in the bloodstream throughout the period of pregnancy. The main difference between the present three-stage hypothesis and other hypotheses is the assertion that, in the pathogenesis of early and late complicated pregnancy, methemoglobin takes on an important role. Methemoglobin by itself and from heme, redox-active ferric iron as a product of methemoglobin catabolism, has prooxidant properties and causes important structural and functional changes in the vascular endothelium, such as growth arrest, senescence, morphological alterations and cell apoptosis. Our own prospective study of methemoglobin in pregnancy revealed a significant rise and correlation between the ground level of SO2 and the level of methemoglobin: >1.5 g/L (r = 0.72, p 2, NOx, NO, NO2 and others) and that is an early biomarker of the identification of women with a pregnancy risk, and having an significant role upon adverse effects on mother and fetus health.

关键词： Methemoglobinemia Mother and Fetal Preeclampsia three-stage Disorders Environmental Oxidants Biomarker Nitrogen and Sulphur Synergy

Complex Least Squares Adjustment to Improve Tree Height Inversion Problem in PolInSAR

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Journal of Geodesy and Geoinformation Science 2019年第1期2卷 1-8页

作者： Jianjun ZHU Qinghua XIE Tingying ZUO Changcheng WANG Jian XIE School of Geosciences and Info-Physics Central South UniversityChangsha 410083China

At present,the principal data processing methods involving complex observations are based on two strategies according to characteristics of the observation process,i.e.,step-by-step and direct ***,these strategies have some limitations,*** cannot consider statistical observation error information,redundant observations and so *** paper applies least squares methods to complex data processing to extend surveying adjustment theory from real to complex number *** compared the two adjustment criteria for a complex domain in a quantitative *** order to understand the effectiveness of complex least squares,tree height inversion from PolInSAR data is taken as an *** firstly established both a complex adjustment function model and a stochastic model for PolInSAR tree height inversion,and then applied the complex least squares method to estimate tree *** show that the complex least squares approach is reliable and outperforms other classic tree height retrieval methods;the method is simple and easy to implement.

关键词： surveying adjustment complex least squares polarimetric interferometric SAR (PolInSAR) tree height inversion three-stage algorithm