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Chinese Journal of Chemical Engineering 2022年第4期35卷 29-40页

作者： Kexin Bi Mingyu Yan Shuyuan Zhang Tong Qiu Department of Chemical Engineering Tsinghua UniversityBeijing 100084China Beijing Key Laboratory of Industrial Big Data System and Application Beijing 100084China Fushun Petrochemical Company PetroChinaFushun 113008China

In order to explore the potential of profit margin improvement,a novel three-scale integrated optimization model of furnace simulation,cyclic scheduling,and supply chain of ethylene plants is proposed and evaluated.A decoupling strategy is proposed for the solution of the three-scale model,which uses our previously proposed reactor scale model for operation optimization and then transfers the obtained results as a parameter table in the joint MILP optimization of plant-supply chain scale for cyclic *** optimization framework simplifies the fundamental mixed-integer nonlinear programming(MINLP)into several sub-models,and improves the interpretability and *** the evaluation of an industrial case,a profit increase at a percentage of 3.25%is attained in optimization compared to the practical *** sensitivity analysis is carried out for strategy evolving study when price policy,supply chain,and production requirement parameters are *** results could provide useful suggestions for petrochemical enterprises on thermal cracking production.

关键词： Three-scale integrated optimization Cyclic scheduling Supply chain Mixed-integer linear programming Thermal cracking

Knowledge expression,numerical modeling and optimization application of ethylene thermal cracking:From the perspective of intelligent manufacturing

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Chinese Journal of Chemical Engineering 2021年第10期34卷 1-17页

作者： Kexin Bi Shuyuan Zhang Chen Zhang Haoran Li Xinye Huang Haoyu Liu Tong Qiu Beijing Key Laboratory of Industrial Big Data System and Application Department of Chemical EngineeringTsinghua UniversityBeijing 100084China

Applications of process systems engineering(PSE)in plants and enterprises are boosting industrial reform from automation to digitization and *** ethylene thermal cracking,knowledge expression,numerical modeling and intelligent optimization are key steps for intelligent *** paper provides an overview of progress and contributions to the PSE-aided production of thermal cracking;introduces the frameworks,methods and algorithms that have been proposed over the past10 years and discusses the advantages,limitations and applications in industrial *** entire set of molecular-level modeling approaches from feedstocks to products,including feedstock molecular reconstruction,reaction-network auto-generation and cracking unit simulation are *** control and optimization methods are exhibited,including at the operational,cycle,plant and enterprise *** software packages are ***,an outlook in terms of future directions is presented.

关键词： Ethylene thermal cracking PSE Intelligent manufacturing Molecularization and digitization Modeling and optimization

The Arrangement and Size of Cellulose Microfibril Aggregates in the Cell Walls of Sclerenchyma Fibers and Parenchyma Tissue in Bamboo

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Journal of Renewable Materials 2021年第12期9卷 2291-2301页

作者： Wenting Ren Fei Guo Minghui Liu Haocheng Xu Hankun Wang Yan Yu Institute of New Bamboo and Rattan Based Biomaterials International Center for Bamboo and RattanBeijing100102China College of Material Engineering Fujian Agriculture and Forestry UniversityFuzhou350108China NFGA and Beijing Co-Built Key Laboratory of Bamboo and Rattan science&Technology National Forestry and Grassland AdministrationBeijing100102China

Understanding the assembly and spatial arrangement of bamboo cell wall components is crucial for its optimal *** cell walls consist of aggregates of cellulose microfibrils and *** the present study,the size and arrangement of cellulose microfibril aggregates in the cell walls of sclerenchyma fibers and parenchyma cells in moso bamboo were investigated with NMR and *** NMR measurement showed that the characteristic sizes of the microfibril aggregates of fibers and parenchyma cells were approximately 25.8 nm and 18.8 nm,***,high-resolution SEM showed the size of microfibril aggregates varied little across the cell wall of sclerenchyma ***,there were significant size differences between the broad and narrow lamellae both in fiber and parenchyma cells,which is thought to be closely related to the orientation of microfibrils in these *** microfibril aggregates in the fibers mainly appear in a random arrangement,although occasionally in a radial or tangential arrangement in individual *** cells have a relatively thinner cell wall layers,in which microfibril aggregates appear in a concentric lamellar arrangement.

关键词： Bamboo fiber parenchyma cell microfibril aggregate size arrangement

Mn-mediated reductive C(sp3)–Si coupling of activated secondary alkyl bromides with chlorosilanes

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Chinese Chemical Letters 2022年第12期33卷 5061-5064页

作者： Liangliang Qi Xiaobo Pang Kai Yin Qiu-Quan Pan Xiao-Xue Wei Xing-Zhong Shu State Key Laboratory of Applied Organic Chemistry(SKLAOC) College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China School of Chemistry and Chemical Engineering Southeast UniversityJiangsu Optoelectronic Functional Materials and Engineering LaboratoryNanjing 211189China Zhejiang Nanjiao Chemistry Co. Ltd.Shangyu Economic and Technological Development ZoneShangyu 312369China

The construction of secondary alkylsilanes is a challenging subject in the synthetic *** cross-coupling provides a practical solution to address this problem,but it typically relies on organometallic ***,we report an Mn-mediated reductive C(sp^(3))-Si coupling to synthesize these compounds from alkyl and silyl *** approach avoids the requirement for activation of Si-Cl by transition metals and thus allows for the coupling of various common *** reaction proceeds under mild conditions and shows good functional group *** method offers access toα-silylated organophosphorus and sulfones with a scope that is complementary to those obtained from the established methods.

关键词： Organosilanes Alkylsilanes Reductive coupling Chlorosilanes Organophosphorus Sulfones

Photopolymerization induced by a benzophenone derivative photoinitiator

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Chinese Chemical Letters 2007年第8期18卷 977-980页

作者： Ying Wang Pu Xiao Gang Qiang Wu Su Qing Shi Jun Nie State Key Lab of Chemical Resource Engineering College of Material Science and Engineering Beifing University of Chemical Technology Beifing 100029 China Key Laboratory of Biomedical Polymers of Ministry of Education Department of Chemistry Wuhan University Wuhan 430072 China

A benzophenone derivative photoinitiator, HBP-TDI-HQ-TDI-HBP （HTCTH）, was synthesized based on 4-hydroxy benzophenone （HBP）, toluene-2,4-diisocyanate （TDI） and hydroquinone （HQ）. HTCTH was a more effective photoinitiator which had longer wavelength absorption in the UV-vis absorption spectra than the low molecular counterpart benzophenone （BP）. It showed that both rate of polymerization （Rp） and final conversion （P） increased with increase of amine and HTCTH concentration in photopolymerization.

关键词： Photopolymerization Benzophenone derivative Jamine Kinetics

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Paths out of poverty

Journal of Integrative Agriculture 2021年第4期20卷 851-856页

作者： NIE Feng-ying BI Jie-ying Apurv MARU Agricultural Information Institute Chinese Academy of Agricultural sciences(CAAS)Beijing 100081 P.R.China

Introduction Ending poverty in all its forms everywhere is the first Sustainable Development Goal(SDG) of the United Nations(2021a). Progress towards this goal has varied but also been fruitful. Between 1990 and 2015, over a billion people were lifted out of extreme poverty(World Bank 2018). From 36% of the population under extreme poverty in 1990 to 10% in 2015(United Nations 2021b).

关键词： Sustainable extreme poverty

Microstructure and Tribological Properties of Plasma-sprayed Nanostructured Sulfide Coating

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Journal of Materials science & Technology 2006年第5期22卷 589-593页

作者： Yang XU Yaohui GUAN Zhongyu ZHENG Xiaohui TONG College of Engineering China Agricultural UniversityBeijing 100083China Beijing Research Institute of Mechanical and Electrical Technology Beijing 100083China

The friction and wear properties of plasma-sprayed nanostructured FeS coating were investigated on an MHK- 500 friction and wear tester under both oil lubrication and dry friction condition. The microstructure, worn surface morphology and phase composition of the coating were characterized by scanning electron microscopy （SEM） and X-ray diffraction （XRD）. It was found that the coating was mainly composed of FeS. a small quantity of Fe1-xS and oxide were also found. The coating was formed by small particles of 50～100 nm in size The thickness of the coating is approximately 150 μm. The friction-reduction and wear-resistance properties of plasma-sprayed nanostructured FeS coating were superior to that of GCr15 steel substrate. Especially under oil lubrication condition, the friction coefficient of nanostructured FeS coating was 50% of that of GCr15 steel, the wear scar widths of the coating were also reduced to nearly 50% of that of GCr15 steel under high load. The failure of the coating was mainly attributed to plastic deformation under both oil lubrication and dry friction condition.

关键词： Plasma spray Nanostructured Sulfide Friction and wear

Fixation of CO_2 by electrocatalytic reduction to synthesis of dimethyl carbonate in ionic liquid using effective silver-coated nanoporous copper composites

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Chinese Chemical Letters 2010年第8期21卷 987-990页

作者： Xuan Yun Wang Su Qin Liu Ke Long Huang Qiu Ju Feng De Lai Ye Bing Liu Jin Long Liu Guan Hua Jin College of Chemistry and Chemical Engineering Central South UniversityChangsha 410083China

With high surface area,open porosity and high efficiency,a catalyst was prepared and firstly employed in electrocatalytic reduction of CO2 and electrosynthesis of dimethyl carbonate（DMC）.The electrochemical property for electrocatalytic reduction of CO2 in ionic liquid was studied by cyclic voltammogram（CV）.The effects of various reaction variables like temperature,working potential and cathode materials on the electrocatalytic performance were also investigated.80%yield of DMC was obtained under the optimal reaction conditions.

关键词： Electrocatalytic Carbon dioxide Nanoporous Dimethyl carbonate Ionic liquid

Exploring the complex trade-offs and synergies of global ecosystem services

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Environmental science and Ecotechnology 2024年第5期21卷 141-148页

作者： Jinnan Wang Wenjun Wu Meng Yang Yueming Gao Jiacheng Shao Weishan Yang Guoxia Ma Fang Yu Nan Yao Hongqiang Jiang State Environmental Protection Key Laboratory of Environmental Planning and Policy Simulation Chinese Academy of Environmental PlanningBeijing100041China The Center for Eco-Environmental Accounting Chinese Academy of Environmental PlanningBeijing100041China The Innovation Center for Eco-environment-Oriented Development Chinese Academy of Environmental PlanningBeijing100041China School of Environment Beijing Normal UniversityBeijing100875China College of Environmental&Resource sciences Zhejiang UniversityHangzhou310058China College of Economics&Management Northwest A&F UniversityYangling712100China

The trade-off and synergy relationship of ecosystem services is an important topic in the current *** value of each service provided by the ecosystem is substantially affected by human activities,and conversely,its changes will also affect the relevant human *** to varying tradeoffs among ecosystem services and synergies between them that can either increase or decrease,it is difficult to optimize multiple ecosystem services simultaneously,making it a huge challenge for ecosystem *** study firstly develops a global Gross Ecosystem Product(GEP)accounting *** uses remote sensing data with a spatial resolution of 1 km to estimate the ecosystem services of forests,wetlands,grasslands,deserts,and farmlands in 179 major countries in *** results show that the range of global GEP values is USD 112e197 trillion,with an average value of USD 155 trillion(the constant price),and the ratio of GEP to gross domestic product(GDP)is *** tradeoffs and the synergies among different ecosystem services in each continent and income group have been further *** found a correspondence between the income levels and the synergy among ecosystem services within each *** specific ecosystem services,there are strong synergies between oxygen release,climate regulation,and carbon sequestration services.A trade-off relationship has been observed between flood regulation and other services,such as water conservation and soil retention services in low-income *** results will help clarify the roles and the feedback mechanisms between different stakeholders and provide a scientific basis for optimizing ecosystem management and implementing ecological compensation schemes to enhance human well-being.

关键词： Ecosystem services Biophysical quantity Monetary value Trade-off Synergy

Deformation characteristics and safety assessment of a high-speed railway induced by undercutting metro tunnel excavation

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Journal of Rock Mechanics and Geotechnical Engineering 2019年第1期11卷 88-98页

作者： Wangping Qian Taiyue Qi Yunjian Zhao Yizhou Le Haiyang Yi Key Laboratory of Transportation Tunnel Engineering Ministry of Education Southwest Jiaotong University School of Civil Engineering Southwest Jiao tong University China Railway Design Corporation China Changjiang Construction Investment Corp.Ltd. North China Institute of science and Technology

Stratum deformation(settlement) is a challenging issue in tunnel engineering, especially when construction of metro tunnels has to undercut high-speed railway. For this purpose, we used the FLAC30 software to analyze the stratum settlement characteristics of high-speed railway at different crossing angles intersected by metro tunnel, in terms of ground settlement trough, stratum slip line and irregularity of ballastless tracks. According to the evolution of the stratum settlement at different angle regions, an optimized angle is proposed for the actual project design. In order to reduce the influence of stratum settlement on the safety of high-speed railway, an approach of safety assessment is proposed for the shield engineering undercutting high-speed railway, as per Chinese specifications using numerical results and on-site conditions. A case study is conducted for the shield tunnel section crossing the Wuhan-Guangzhou High-speed Railway between the Guangzhou North Railway Station and the Huacheng Road Station, which represents the first metro tunnel project passing below a high-speed railway in China. A series of measures is taken to ensure the safe excavation of the shield tunnel and the operation of the high-speed railway. The results can provide a technical support for performing a safety evaluation between high-speed railways and metro tunnels.

关键词： Metro tunnel excavation High-speed railway Settlement characteristics Safety assessment Numerical simulation Case application