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Chinese Journal of Polymer Science 2007年第6期25卷 545-553页

作者： li-ming Tang ji feng Yu Wang Advanced Materials Laboratory Department of Chemical Engineering Tsinghua University Beijing 100084 China

Five secondary amine terminated poly（ester-amine）s （defined as PEA） with controlled molecular structures were synthesized through reacting excessive piperazine with phthalicdiglycol diacrylate （PDDA） and 1,1,1-trimethylolpropane triacrylate （TMPTA） at a constant secondary amine/acrylate group ratio of 1.5/1 and at different PDDA/TMPTA molar ratios. Both IR and ^1H-NMR spectra indicated that all acrylate groups were consumed in the reaction, based on which the structural parameters were calculated from the ^1H-NMR spectra. With decreasing PDDA/TMPTA ratio, the content of secondary amine, degree of branching, molecular weight, Tg and Td increased accordingly. These polymers were further used as both crosslinkers and flexibilizers for a linear epoxy resin E51 to form cured films under ambient condition. The gel content, relative hardness and Tg of the resulting films increased as PEA molecules changed from linear to highly branching structures. Due to the flexibility of PEA molecules, all the films possessed excellent mechanical performance.

关键词： Poly(ester-amine) Molecular structure Epoxy resin Cured film.

Flexible scheduling ensuring inter-ONU-group fairness in 1G/10G EPON coexistence system

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The Journal of China Universities of Posts and Telecommunications 2009年第4期16卷 16-22页

作者： li Qi li Hui ji Yue-feng Key Laboratory of Optical Communications and lightwave Technologies Beijing University of Posts and Telecommunications Beijing 100876 China

In recent years, 10 Gbit/s Ethemet passive optical networks （10G EPON） have been gaining considerable interests because of its high bandwidth capability. To ensure smooth transition from 1 Gbit/s to 10 Gbit/s equipment and to avoid a significant one-time investment into such a cost-sensitive market, coexistence of gigabit Ethernet passive optical networks （GEPON） and 10G EPON system are necessary. In this article, coexistence system architecture and a novel bandwidth allocation algorithm called weight-optimized dynamic bandwidth allocation for coexistence EPON （WOCE-DBA） for the system is proposed. The simulation results show that this algorithm can guarantee fair bandwidth sharing among different optical network unit （ONU） groups, without ignoring the inter-ONU and intra-ONU fairness. Most importantly, it can flexibly adapt to the system composition variations and save efforts needed to modify the bandwidth scheduling mechanism during the migration process from GEPON to 10G EPON.

关键词： 10G EPON coexistence system dynamic bandwidth allocation (DBA) intra-ONU-group fairness simulation and modeling

Multi-model comparison of CO2 emissions peaking in China:Lessons from CEMF01 study

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Advances in Climate Change Research 2018年第1期9卷 1-15页

作者： Oleg LUGOVOY feng Xiang-Zhao GAO ji li ji-feng liU Qiang TENG Fei ZOU Le-Le Environmental Defense Fund Washington DC 20009USA Policy Research Center for Environment and Economy Ministry of Environmental ProtectionBeijing 100029China Environmental Defense Fund Beijing 100007China Policy Simulation Laboratory State Information CenterBeijing 100045China National Center for Climate Change Strategy and International Cooperation Beijing 100038China Institutes of Energy Environmentand EconomyTsinghua UniversityBeijing 100084China Institute of Policy and Management Chinese Academy of SciencesBeijing 100190China

The paper summarizes results of the China Energy Modeling Forum's(CEMF)first *** emissions peaking scenarios,consistent with China's Paris commitment,have been simulated with seven national and industry-level energy models and *** CO2 emission trends in the considered scenarios peak from 2015 to 2030 at the level of 9e11 ***-level analysis suggests that total emissions pathways before 2030 will be determined mainly by dynamics of emissions in the electric power industry and transportation *** sectors will experience significant increase in demand,but have low-carbon alternative options for *** on a side-by-side comparison of modeling input and results,conclusions have been drawn regarding the sources of emissions projections differences,which include data,views on economic perspectives,or models'structure and theoretical *** suggestions have been made regarding energy models'development priorities for further research.

关键词： Carbon emissions projections Climate change CO2 emissions peak China’s Paris commitment Top-Down energy models Bottom-Up energy models Multi model comparative study China Energy Modeling Forum(CEMF)

Resources allocation in an Intserv/Diffserv integrated EPON system

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The Journal of China Universities of Posts and Telecommunications 2009年第3期16卷 108-113,121页

作者： liU Qiong li Hui ji Yue-feng QIAO Yao-jun Key Laboratory of Optical Communications and lightwave Technologies Beijing University of Posts and Telecommunications Beijing 100876 China

As one of the most promising next-generation access network （EPON） should pay more attention to its quality of service （QoS）, techniques, the user-oriented Ethernet passive optical network However, now the EPON adopts mostly differentiated services model （Diffserv） that only provides quality control on traffic aggregation, whereas, the quality of user session cannot be guaranteed when the network is overloaded with substantial connections. This article proposes to apply integrated services model （Intserv） in Diffserv-based EPON, which uses per-flow processing to guarantee QoS. In the simulation, a framework of combined Diffserv and Intserv model is employed in an EPON system, with a dynamic bandwidth allocation algorithm that adapts to it. The simulation results demonstrate that the EPON system with the combined models can provide more flexible, various control for user-oriented service quality.

关键词： QoS Intserv Diffserv resource reservation

Analysis on energy demand and CO2 emissions in China following the Energy Production and Consumption Revolution Strategy and China Dream target

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Advances in Climate Change Research 2018年第1期9卷 16-26页

作者： li ji-feng MA Zhong-Yu ZHANG Ya-Xiong WEN Zhi-Chao Policy Simulation Laboratory State Information CenterBeijing 100045China School of Environment and Natural Resources Renmin University of ChinaBeijing 100872China

A quantitative model was applied to analyze the energy demand and CO2 emissions in China following the Energy Production and Consumption Revolution Strategy(2016e2030)and long-term economic and social development target China *** showed that 1)toward the 2050 China Dream target,total final energy consumption is expected to peak at 3.9 Gtce in 2030 and remain stable until 2050,whereas total primary energy consumption is expected to reach an upper platform by 2040 and around 5.8 Gtce by 2050;2)the proportion of non-fossil fuels is expected to reach approximately 50%and that of natural gas to reach more than 16%by 2050;3)CO2 emissions from energy use are expected to peak at 9.6 Gt by no later than 2030 and then gradually decline to 6.7 Gt by 2050.

关键词： China energy strategy China Dream strategy CO2 emission pathway Energy demand and supply model

Shared p-cycles design for dual link failure restorability in optical WDM networks

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The Journal of China Universities of Posts and Telecommunications 2007年第3期14卷 74-78页

作者： XIE Zheng-cheng XING Jun-wei WU li ji Yue-feng Key Laboratory of Optical Communications and lightwave Technologies Beijing University of Posts and Telecommunications Beijing 100876 China

Pre-configured cycles （p-cycles） can attain high capacity efficiency and fast protection switching times in wavelength division multiplexing （WDM） networks. This article proposes the weighted straddling link algorithm（WSLA） for generating a subset of all cycles that can guarantee 100% restorability in case of dual link failure, and give an integer linear programming（1LP） formulation that solves the shared p-cycles design problem minimizing the total spare capacities. Numerical result shows that our method can achieve 100% dual link failure restorability with acceptable spare capacity. The larger standard deviation of demand set and the larger node degree network, the better the shared p-cycles scheme performs.

关键词： dual link failure p-cycles WDM

Economic development, energy demand, and carbon emission prospects ofChina's provinces during the 14th Five-Year Plan period: Application ofCMRCGE model

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Advances in Climate Change Research 2019年第3期10卷 165-173页

作者： li ji-feng GU A-Lun MA Zhong-Yu ZHANG Cheng-Long SUN Zhen-Qing State Information Center Beijing100045China Institute o f Energy Environment and EconomyTsinghua UniversityBeijing100084China State Grid Energy Research Institute Co”Ltd”Beijing 102209China Tianjin Science and Technology University Tianjin300222China

This study focuses on a national regional coordinated development strategy and adopts China Multi-Regional Computable General Equilibrium model to analyze the economic and social development, energy demand, and carbon emissions of the provinces during the 14th Five-Year Plan (FYP, 2021 2025) period based on the economic development and energy demand since the New Normal. The main conclusions are the following: 1) Under the guidance of the regional coordinated development strategy, 13 provinces/municipalities are expected to have a per capita gross domestic product (GDP) of more than US$15,000, and 16 provinces/municipalities will have a per capita GDP of US$10,000 15,000. All provincial economies are expected to achieve steady and rapid development by the end of the 14th FYP. 2) The total energy consumption of the provinces is expected to reach 5.45 Gtce (excluding Tibet) in 2025, and the average annual growth rate is approximately 1.5%. The growth of energy demand will remain in low speed. The key point of energy demand will gradually shift from the eastern to the middle area, while the proportion of energy use in the western provinces will remain stable, which is consistent with the economic development stage and regional coordinated development strategy. 3) The annual average carbon intensity (mainly considering carbon emissions from energy use) of the provinces will approximately with most provinces dropping by over 4.0%. The trend of a considerable decline in carbon intensity, as observed in recent years, is expected to continue.

关键词： Coordinated development CMRCGE model 14th Five-Year Plan Energy demand Carbon emissions

Theoretical Studies on the Structures and Reactions of Halocarbenoids(Ⅰ)Structures and Stability of Chlorocarbenoid CHCl_2

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Chemical Research in Chinese Universities 1997年第3期13卷 256-261页

作者： li li ji-hai, feng Sheng-yu,liu Wei (Chemical College,Shandong University,jinan, 250100) SHANDONG UNIV CHEM COLLJINAN 250100PEOPLES R CHINA

The chlorocarbenoid , CHCl2li , was studied by means of ab initio molecular or- bital theory. Three equilibrium structures and two isomerization transition states were located. The calculations showed that the three-membered ring structure is the most stable. The 'classical tetrahedral' structure is not the local minimum on the potential energy surface.

关键词： Chlorocarbenoid isomeric structure Ab initio molecular orbital calcu- lation

Policy Implications for Carbon Trading Market Establishment in China in the 12th Five-Year Period

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Advances in Climate Change Research 2012年第3期3卷 163-173页

作者： li ji-feng ZHANG Ya-Xiong WANG Xin CAI Song-feng Economic Forecasting Department State Information CenterBeijing 100045China

Based on the survey of international emissions trading system （ETS） and quantitative analysis, policy suggestions on establishing a carbon ETS in China are presented in this study. Sectors sensitive to carbon prices, e.g., the power generation sector and the iron and steel industry, are given priority to be covered by the ETS. Interregional carbon trading should be carried out as early as possible. The cap of the ETS should be based on China＇s carbon intensity reduction target with the floor carbon price for the market being set in the beginning. Suggestions on the infrastructure of ETS are also proposed, including the national wide carbon measuring, reporting, verification system building. account registration system and the legislation to national

关键词： carbon trading system cap of allowance distribution of allowance carbon price infrastructure of carbonmarket

High Energy Proton-Proton Elastic Scattering in the Pomeron Exchange Model

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Communications in Theoretical Physics 2002年第7期38卷 65-67页

作者： HU Zhao-Hui ZHANG jian ZHOU li-Juan liU ji-feng MA Wei-Xing Department of Information and Computing Science Guangxi University of Technology Liuzhou 545006 China Department of Physics Guangxi Normal University Guilin 541004 China Department of Information and Computing Science Guangxi University of Technology Liuzhou 545006 China Department of Physics Guangxi Normal University Guilin 541004 China Department of Information and Computing Science Guangxi University of Technology Liuzhou 545006 China Institute of High Energy Physics the Chinese Academy of Sciences Beijing 100039 China Institute of Theoretical Physics the Chinese Academy of Scie

We study high energy proton-proton elastic scattering in the framework of Pomeron exchange model. The cross section of the process are calculated without any free parameters. Our finding is that Pomeron exchange theory gives perfect fits to total cross section at the energy of√s higher than 10 GeV and to differential cross section at the momentum transfer [t] less than 1.5 GeV2. For total cross section at lower energy √s ＜ 10 GeV and differential cross section at larger momentum transfer region of |t| ＞ 1.5 GeV2, the Pomeron exchange theory needs to be improved.

关键词： proton-proton elastic scattering, Pomeron exchange, cross section