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Construction and Analysis of Common Foreign Trade Cycle Based on MS-VAR:An Empirical Study of Global Experience

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Journal of Systems Science & Complexity 2015年第2期28卷 360-380页

作者： zhang lili zhang Xun CHENG Ke Academy of Mathematics and Systems Science Chinese Academy of Sciences

This paper proves the co-movement of foreign trade in different countries or areas which belong to ten economic regions by MS-VAR *** studies show that trade crisis lags behind economic crisis and spreads from the core of the economic crisis to its periphery which is closely-related with *** trade crisis corresponding to the US subprime crisis spreads faster than before,which has struck worldwide foreign *** order to get the main factors affecting trade crisis,the authors construct composite indices which are proxies of economic growth and price levels of internal and external *** results of logistic and linear panel models show that economic growth affects more to trade cycle than price *** results of panel models with dummy variable of trade crisis show that the outside economic growth do bad to the recovery of internal foreign trade during trade crisis corresponding to Mexican peso crisis,the Asian financial crisis and the Russian debt crisis,while the opposite is true during the internet bubble burst and the US subprime crisis.

关键词： Business cycle foreign trade crisis foreign trade cycle MS-VAR model panel model.

The case-dependent lignin role in lignocellulose nanofibers preparation and functional application-A review

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Green Energy & Environment 2023年第6期8卷 1553-1566页

作者： Xiya zhang lili zhang Yimin Fan Zhiguo Wang Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources International Innovation Center for Forest Chemicals and MaterialsCollege of Light Industry and Food EngineeringCollege of Chemical EngineeringNanjing Forestry UniversityNanjing 210037China

Lignocellulose nanofibers(LCNFs) as a new material is attracting extensive attention. The pretreatment and mechanical fibrillation are the two main stages involved in the preparation of LCNFs, and lignin plays the important role of these two stages. This review discussed the interaction between lignin and chemicals in the pretreatment stage, and discovered the general law of the effect of lignin in the mechanical fibrillation *** exhibits both promotion and inhibition effects on mechanical fibrillation, and the mutual competition between the two effects ultimately affects the energy consumption, morphology and yield of LCNFs. Furthermore, the recent research progress related to the contributions of lignin on the functional application of LCNFs was summarized, aiming to provide profound guidance for the preparation and application of LCNFs.

关键词： Lignocellulose nanoﬁbers Lignin Fibrillation Cellulose Pretreatment

A 2D numerical study on the condensation characteristics of three non-azeotropic binary hydrocarbon vapor mixtures on a vertical plate

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Chinese Journal of Chemical Engineering 2020年第11期28卷 2746-2757页

作者： lili zhang Guanmin zhang Yi zhang Maocheng Tian Jingzhi zhang School of Energy and Power Engineering Shandong UniversityJinan 250061China

To improve the transportation efficiency and reduce the supply cost,the liquefaction becomes an important technology to store and transport the natural *** the liquefaction,the various components(***,ethane,methane etc.)undergo fractional condensation phenomenon due to their different boiling *** means that when one component condenses,others play a role of non-condensable gas(NCG).In order to reveal the influence mechanism of NCG on this condensation process,a numerical method was employed in this paper to study the condensation characteristics of three non-azeotropic binary hydrocarbon vapor mixtures,namely the propane/methane(80%–95%),ethane/methane(65%–85%)and methane/nitrogen(2%–13%)mixtures,on a vertical *** model was proposed based on the diffusion layer model,and the finite volume method was used to solve the governing equations.A user defined function was developed by cell iterative method to obtain the source terms in the condensation *** numerical results show that the gas phase boundary layer formed by the NCG becomes the main resistance to the reduction of heat transfer *** for the above three mixtures,there is a negative correlation between the NCG concentration and the heat transfer ***,the results show a good agreement with the experimental data,meaning that the proposed model is *** mixtures within same non-condensable mole fraction of 20%were also investigated,indicating that the mixtures with a higher binary hydrocarbon molecular ratio have a lower heat transfer *** a result,the presence of the lighter NCG contributes to a thicker boundary layer.

关键词： Condensation characteristics Non-azeotropic hydrocarbon mixtures Heat and mass transfer Liquid film distribution Vertical plate

Dynamic Research on Cold Storage Performance of a Standard Radiant Floor Cooling System for Office Buildings in Northern China

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Journal of Thermal Science 2022年第6期31卷 1928-1938页

作者： WANG Xiaolong MAN Yi zhang lili zhang Wenke zhang Linhua School of Thermal Engineering Shandong Jianzhu UniversityJi'nan 250101China

Due to the wide application of floor heating systems, the radiant floor cooling systems has developed rapidly in recent years. In this paper, TRNSYS numerical simulation methods are used to study the influence of chilled water supply temperature and flow rate on the cold storage characteristics of a standard floor structure for office buildings in northern China. The results are verified by experimental measurements. The functional relationship between the saturated cold storage time and the chilled water flow rate is quadratic polynomial, while the changes of supply-water temperature have no effect on the saturation time;the supply-water temperature has a linear relationship with the saturated cold storage volume, while the chilled water flow rate has almost no effect on the saturation cold storage volume. The accumulated cold volume of floor changes with time in an exponential distribution with four coefficients, and the floor has the characteristics of rapid cold storage. This paper is instructive for the design, application and promotion of radiant floor cooling systems.

关键词： radiant floor cooling chilled water saturation time saturated volume

Yb^(3+)-doped Fluorophosphate Glass with High Cross Section and Lifetime

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Journal of Materials Science & Technology 2010年第10期26卷 921-924页

作者： Liyan zhang Yuxin Leng Junjie zhang lili Hu Key Laboratory of Materials for High Power Laser Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800 China

Yb3＋ doped fluorophosphate （FP/Yb） glasses with emission cross section and fluorescence lifetime as high as 0.8388×10-20 cm 2 and 2.3 ms were developed,and AlF3 content is proved to decrease the lifetime *** scale glass casting procedure shows high Tx-Tg doesn t make better casting crystallization stability in *** Yb laser is difficult to be obtained in FP glass,a 230 mw laser was still achieved from 2 mm thick samples under 976 nm LD excitation because of the large gain parameter（σemiτf） of the FP/Yb *** test also proved the relationship between laser output and gain *** with its wide and flat effective gain property,this FP/Yb glass is a practical new potential material for low power ultra-short pulse application.

关键词： FP15/Yb glass Crystallization stability Gain parameter

Assessing the potential of crop residue recycling in China and technology options based on a bottom-up model

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Frontiers of Environmental Science & Engineering 2014年第4期8卷 570-579页

作者： lili QU Tianzhu zhang Wei LU Institute of Environmental Management and Policy School of Environment Tsinghua University Beijing 100084 China

Crop residues are an important biomass, and are significant in the sustainable development of China. This paper uses the Grey-Markov modeling approach, the cost-benefit analysis method, and the constraint optimiza- tion method to establish the potential of crop residue recycling in China （CRRC） using a bottom-up analysis. Taking 2010 as the baseline year, the CRRC model is used to determine the quantity trends of crop residue resources, simulating the recycling potential and selecting key crop residue recycling technologies for operation between 2010 and 2030. The results illustrate that the total residue output from different crops will gradually increase to 1062 million tons in 2030. The proportion of crop residue for field burning is expected to decrease as a result of guidance and support from the government. Market mechanisms are also improving the development of the crop residue recycling industry. The economic benefit of crop residue recycling is expected to be worth 132 billion CNY in 2030 according to technology structure options. Key crop residue recycling technologies preferred such as liquefaction, amination, silo, co-firing straw power and composting will account for more than 85% of the total benefits.

关键词： China crop residue recycling potential technology options

Editorial for a special issue on:(Photo)electrochemical materials and devices

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Nano Materials Science 2023年第2期5卷 117-118页

作者： Maowen Xu Yuxin zhang lili zhang Institute for Clean Energy&Advanced Materials School of Materials and EnergySouthwest UniversityChongqing400715PR China College of Materials Science and Engineering Chongqing UniversityChongqing400044PR China Catalysis&Green Process Engineering Institute of Sustainability for ChemicalsEnergy and Environment627833Singapore

With the development of human society and the depletion of non-renewable energy sources,alternate energy resources are becoming an urgent *** recent years,energy storage and conversion devices have drawn wide attentio... 详细信息

关键词： becoming depletion urgent

Multifunctional Measurement System for High Precision Planetary Servo Gearhead

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Chinese Journal of Mechanical Engineering 2012年第2期25卷 398-404页

作者： FAN Shuqian zhang lili WANG Lei SHI Mingquan School of Mechatronics Engineering University of Electronic Science and Technology of ChinaChengdu 611731China

As an essential component of a servo system,mechanical properties of high precision planetary servo gearhead direct influence on the validation,stability and accuracy of the servo control ***,mechanical properties measurement and assessment for high precision planetary servo gearhead is a time-consuming and tedious work,since current methodologies typically rely on various different specified *** integrated multifunctional measurement system SFJC-I is developed,which employs a torque sensor and a laser displacement transducer to simultaneously measure torque applied on servo gearhead and its corresponding torsional *** measurement system depends on the accurate measurement of the relative displacement between input clamping system and output shaft of servo gearhead with a lever-type enlarging mechanism,rather than traditional optical dividing head and optical multisurface *** interchangeable fixture system,the developed system capability to measure almost all series and specifications of high precision planetary servo gearhead is *** proposed hardware platform configuration and developed measuring software,mechanical properties such as backlash,torsional stiffness,hysteresis plot and emergency stop torque,can be measured accurately and assessed reliably.A torsion test with standard circular specimen is carried out with the multifunctional measurement *** result of test shows that the measurement error is within ±3σ and the measurement reliability is more than 99.97%.The problem of accurate measurement and reliable assessment of mechanical properties for high precision planetary servo gearhead is fully solved with the developed multifunctional measurement system.

关键词： servo gearhead measurement hysteresis plot emergency stop torque

One-pot Sequential Reaction for the Synthesis of Polysubstituted 3-（3-Nitro-2-phenylchroman-4-yl）-3-arylaminoacrylates

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Chinese Journal of Chemistry 2013年第12期31卷 1546-1550页

作者： lili zhang Jing Sun Chaoguo Yan College of Chemistry & Chemical Engineering Yangzhou University Yangzhou Jiangsu 225002 China

The one-pot sequential reaction of arylamines, methyl propiolate and 2-aryl-3-nitrochromenes without any catalyst in refluxing ethanol afforded the polysubstituted 3-（3-nitro-2-phenylchroman-4-yl）-3-arylaminoacrylates in good yields and with high diastereoselectivity. Reaction mechanism was believed involving the initial formation of β-enamino ester and sequential Michael addition.

关键词： chromene propiolate acrylate arylamine one-pot reaction diastereoselectivity