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Decoupling effect and driving factors of carbon footprint in megacity Wuhan,Central China

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Ecological Processes 2023年第1期12卷 330-343页

作者： Gao pan Xinhang Li deng pan Wensheng Liu College of Life Science and Technology Central South University of Forestry and TechnologyChangsha 410004People’s Republic of China Central South Academy of Inventory and Planning of NFGA Changsha 410014People’s Republic of China

Background China’s 35 largest cities,including Wuhan,are inhabited by approximately 18%of the Chinese popula-tion,and account for 40%energy consumption and greenhouse gas *** is the only sub-provincial city in Central China and,as the eighth largest economy nationwide,has experienced a notable increase in energy ***,major knowledge gaps exist in understanding the nexus of economic development and carbon footprint and their drivers in *** We studied Wuhan for the evolutionary characteristics of its carbon footprint(CF),the decoupling relation-ship between economic development and CF,and the essential drivers of *** on the CF model,we quantified the dynamic trends of CF,carbon carrying capacity,carbon deficit,and carbon deficit pressure index from 2001 to *** also adopted a decoupling model to clarify the coupled dynamics among total CF,its accounts,and eco-nomic *** used the partial least squares method to analyze the influencing factors of Wuhan’s CF and determine the main *** The CF of Wuhan increased from 36.01 million t CO_(2)eq in 2001 to 70.07 million t CO_(2)eq in 2020,a growth rate of 94.61%,which was much faster than that of the carbon carrying *** energy consumption account(84.15%)far exceeded other accounts,and was mostly contributed by raw coal,coke,and crude *** carbon deficit pressure index fluctuated in the range of 8.44-6.74%,indicating that Wuhan was in the relief zone and the mild enhancement zone during *** the same time,Wuhan was in a transition stage between weak and strong CF decoupling and economic *** main driving factor of CF growth was the urban per capita residen-tial building area,while energy consumption per unit of GDP was responsible for the CF *** Our research highlights the interaction of urban ecological and economic systems,and that Wuhan’s CF changes were mainly affected by four factors:city size,economic developm

关键词： Carbon footprint Economic development Decoupling analysis Partial least squares analysis Megacity

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Diffusion and Relaxation Dynamics of Supercooled Polymer Melts

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Chinese Journal of Polymer Science 2018年第10期36卷 1187-1194页

作者： deng pan Zhao-Yan Sun State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China University of Chinese Academy of Sciences Beijing 100049 China Xinjiang Laboratory of Phase Transitions and Microstructures in Condensed Matters College of Physical Science and Technology Yili Normal University Yining 835000 China

The dynamic properties of polymer melts are investigated in the range of normal liquid regime to the supercooled liquid regime. The polymer is modeled as a coarse-grained bead-spring model with chain length ranging from 5 to 160. The mean squared displacement and non-Gaussian parameter are used to describe the self diffusion of polymer beads. We find slow dynamics with decreasing temperature and increasing chain length. The time evolution of non-Gaussian parameters shows two peaks （or one peak one shoulder） in the a-relaxation time, τa, regime and sub-diffusion time regime, respectively, where the first primary peak indicates the dynamic heterogeneity stemmed from the motion of beads, and the secondary peak is the result of correlated motion along a polymer chain. Moreover, the relaxation of polymer beads shows clear two-step decay in supercooled melts and the dynamics shows growing heterogeneity with decreasing temperature. As chain length is increased, a peak of the dynamic susceptibility occurs, and the peak height, x＊4, increases and then reaches a plateau. The curves of the height of the first peak of a2, a2＊, versus τa and the curves of x＊4 versus τa follow two master curves for different chain lengths. Our results indicate the similarity of dynamic heterogeneity dominated by the motion of single bead even the chain length is different. It is interesting to find that the Stokes-Einstein （SE） relation between ra and diffusion coefficient D, D-rq 1, is highly length-scale dependent. The SE relation breaks down in both normal melts regime and supercooled regime at large magnitude of wave vectors, attributed to the non-Brownian motion arising from the chain connectivity and growing heterogeneity due to supercooling. However, the SE relation is reconstructed when the probing length scale is large （at small magnitude of wave vectors）. Our results show a hierarchical physical picture of the supercooled polymeric dynamics.

关键词： Supercooled polymer melt Molecular dynamics simulation Diffusion Relaxation

Pressure Analysis of the Initial Process of Diffusion Combustion Surge in a 350 kW Gas Boiler

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Journal of Thermal Science 2022年第2期31卷 582-589页

作者： GAO Han ZHU Tong pan deng School of Mechanical Engineering Tongji UniversityShanghai 201804China

In order to meet the increasingly stringent requirements for nitrogen oxides(NOx)emissions from gas boilers,flue gas recirculation(FGR)technology is commonly used to achieve ultra-low NOx ***,under some ultra-low NOx combustion conditions with FGR,a surge phenomenon occurs in the boiler,which causes a flameout and should be *** this study,the diffusion combustion surge of gas boiler with a rated power of 350 k W and equipped with FGR device was *** characteristic analysis results of the initial process of combustion surge showed that the high-frequency component of pressure is closely related to combustion stability and its change can provide reference for the occurrence of ***,the initial process of surge was analyzed by wavelet packet entropy *** indicated that the wavelet packet entropy of pressure signals could effectively reflect the stability of combustion in the furnace,and it could also be used to study the occurrence of surge.

关键词： diffusion combustion flue gas recirculation wavelet packet entropy surge gas boiler

Gravitational field around black hole induces photonic spin-orbit interaction that twists light

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Frontiers of physics 2017年第5期12卷 87-90页

作者： deng pan Hong-Xing Xu School of Physics and Technology Wuhan University Wuhan 430072 China

The spin-orbit interaction （SOI） of light has been intensively studied in nanophotonics because it enables sensitive control of photons＇ spin degree of freedom and thereby the trajectories of the photons, which is useful for applications such as signal encoding and routing. A recent study [Phys. Rev. Lett. 117, 166803 （2016）] showed that the SOI of photons manifests in the presence of a gradient in the permittivity of the medium through which the photons propagate; this enhances the scattering of circularly polarized light and results in the photons propagating along twisted trajectories. Here we theoretically predict that, because of the equivalence between an inhomogeneous dielectric medium and a gravitational field demonstrated in transformation optics, a significant SOI is induced onto circularly polarized light passing by the gravitational lens of a black hole. This leads to： i） the photons to propagate along chiral trajectories if the size of the black hole is smaller than the wavelength of the incident photons; ii） the resulting image of the gravitational lens to manifest an azimuthal rotation because of these chiral trajectories. The findings open for a way to probe for and discover subwavelength-size black holes using circularly polarized light.

关键词： spin-orbit interation black hole gravitational lens optical angular momentum

Proteomic Comparison Between Leaves from a Red-Flesh Mutant and Its Wild-Type in Sweet Orange

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Agricultural Sciences in China 2011年第8期10卷 1206-1212页

作者： pan Zhi-yong deng Xiu-xin National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural UniversityWuhan 430070P.R.China

The red-flesh mutant Hong Anliu sweet orange is of high nutritional value due to its lycopene *** previous studies on this mutant fruits suggested that photosynthesis and oxidative stress could promote the formation of mutation ***,leaf rather than fruit is the major part for some important biological processes such as *** this study,we analyzed the proteomic alteration in leaves of the red-flesh mutant Hong Anliu *** wild type （WT）.Ten differentially expressed proteins were identified,of which two were involved in photosynthesis,three in oxidative stress,two in defense,and three in *** high up-regulation of photosynthetic proteins proved the hypothesis that enhanced photosynthesis could provide and transport more substrates into mutant fruits for carotenoid *** to the previous results in fruits,anti-oxidative proteins were highly up-regulated in leaves,suggesting the whole plant of Hong Anliu suffered from enhanced oxidative *** involved in defense and metabolism were also identified,and their possible roles in the mutation were discussed.

关键词： sweet orange lycopene accumulation proteomic photosynthesis oxidative stress

Dimensionality reduction via kernel sparse representation

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Frontiers of Computer Science 2014年第5期8卷 807-815页

作者： Zhisong pan Zhantao deng Yibing WANG Yanyan ZHANG College of Command Information Systems PLA University of Science and Technology Nanjing 210007 China

Dimensionality reduction （DR） methods based on sparse representation as one of the hottest research topics have achieved remarkable performance in many applications in recent years. However, it＇s a challenge for existing sparse representation based methods to solve nonlinear problem due to the limitations of seeking sparse representation of data in the original space. Motivated by kernel tricks, we proposed a new framework called empirical kernel sparse representation （EKSR） to solve nonlinear problem. In this framework, non- linear separable data are mapped into kernel space in which the nonlinear similarity can be captured, and then the data in kernel space is reconstructed by sparse representation to preserve the sparse structure, which is obtained by minimiz- ing a ~1 regularization-related objective function. EKSR pro- vides new insights into dimensionality reduction and extends two models： 1） empirical kernel sparsity preserving projec- tion （EKSPP）, which is a feature extraction method based on sparsity preserving projection （SPP）; 2） empirical kernel sparsity score （EKSS）, which is a feature selection method based on sparsity score （SS）. Both of the two methods can choose neighborhood automatically as the natural discrimi- native power of sparse representation. Compared with sev- eral existing approaches, the proposed framework can reduce computational complexity and be more convenient in prac- tice.

关键词： feature extraction feature selection sparse rep-resentation kernel trick

Mathematical Model and Algorithm of Optimal Resource Allocation in the Large Iron ＆ Steel Complex

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Mathematical Model and Algorithm of Optimal Resource Allocat...

Oxidative coupling of methane in a dual-bed reactor comprising of particle/cordierite monolithic catalysts

第25届中国控制与决策会议

作者： deng pan Yingping Zheng School of Electronic ＆ Information Engineering Tongji University

ISBN: (纸本)9781467355339

The reduction-producing is an important means of energy saving and emission reduction. For this purpose, the augmented vector is used to describe the inputs/outputs of every process in the large iron ＆ steel complex, and then the optimal resource allocation is studied under the conditions of current equipment, technology and the operational level, the mathematical model is constructed to find an optimal resource allocation scheme for every process. The genetic algorithm is used to simulate the resource allocation of the large iron ＆ steel complex, and determine the optimal resource allocation scheme. The taken measures include the reduction of the purchased materials, the full utilization of the recycled materials and the reasonable allocation of the input and output materials of every process. The simulation shows the validity of the mathematical mode and its algorithm. The purpose of energy saving and emission reduction can be achieved to some extent.

关键词： Large Iron & Steel Complex, Reduction-producing Optimal Resource Allocation Mathematical Model Algorithm

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Journal of Natural Gas Chemistry 2010年第6期19卷 600-604页

作者： deng pan Shengfu Ji Wenhua Wang Chengyue Li State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijng 100029 China

A dual-bed reactor was constructed comprising of a 5%Na2WO4-2%Mn/SiO2 particle catalyst and a 4%Ce-5%Na2WO4-2%Mn/SiO2 /cordierite monolithic *** reaction performance of the oxidative coupling of methane （OCM） over the dual-bed reactor system was *** effects of the bed height and operation mode,as well as the reaction parameters such as reaction temperature,CH4/O2 ratio and flowrate of feed gas,on the catalytic performance were *** results indicated that the suggested dual-bed reactor exhibited a good performance for the OCM reaction when the feed gases firstly passed through the particle catalyst bed and then to the monolithic catalyst bed.A CH4 conversion of 38.2% and a C2H4 selectivity of 43.3% could be obtained using the dual-bed reactor with a particle catalyst bed height of 10 mm and a monolithic catalyst bed height of 50 *** the CH4 conversion and C2H4 selectivity have increased by 2.5% and 12.8%,respectively,as compared with the 5%Na2WO4-2%Mn/SiO2 particle catalyst in a conventional single-bed reactor and by 12.9% and 23.0%,respectively,as compared with the 4%Ce-5%Na2WO4-2%Mn/SiO2 /cordierite monolithic catalyst in a single-bed *** catalytic performance of the OCM in the dual-bed reactor system has been improved remarkably.

关键词： oxidative coupling of methane dual-bed reactor monolithic catalysts

Additive Hazards Regression with Random Effects for Clustered Failure Times

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Acta Mathematica Sinica,English Series 2015年第3期31卷 511-525页

作者： deng pan Yan Yan LIU Yuan Shan WU Department of Statistics Chinese University of Hong Kong School of Mathematics and Statistics Wuhan University

Additive hazards model with random effects is proposed for modelling the correlated failure time data when focus is on comparing the failure times within clusters and on estimating the correlation between failure times from the same cluster, as well as the marginal regression parameters. Our model features that, when marginalized over the random effect variable, it still enjoys the structure of the additive hazards model. We develop the estimating equations for inferring the regression parameters. The proposed estimators are shown to be consistent and asymptotically normal under appropriate regularity conditions. Furthermore, the estimator of the baseline hazards function is proposed and its asymptotic properties are also established. We propose a class of diagnostic methods to assess the overall fitting adequacy of the additive hazards model with random effects. We conduct simulation studies to evaluate the finite sample behaviors of the proposed estimators in various scenarios. Analysis of the Diabetic Retinopathy Study is provided as an illustration for the proposed method.

关键词： Additive hazards regression clustered failure times counting process empirical process,frailty model checking random effects