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Three Levels of Tensor Theory

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Journal of Beijing Institute of Technology 2007年第3期16卷 253-255页

作者：晏汀晏 沈成武李之达 Department of Engineering Structure and Mechanics School of ScienceWuhan University of Technology Shanghai Port Machinery plant School of transportation Wuhan University of Technology

There are many forms of tensor theory which are quite different. Discussions are put forward and their relationships are found. The differences between them depend on whether there is metric on the space and the basis... 详细信息

关键词： manifold inner product orthonormal

Evaluation of the stability of vegetated slopes according to layout and temporal changes

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Journal of Mountain Science 2021年第1期18卷 275-290页

作者： LI Yun-peng HU Chao JIAN Li ZHAO Ran LI Chen China Academy of transportation Sciences Beijing 100029China. Qilu transportation Development Group Jinan 250101China

Vegetation in slopes can effectively improve slope ***,it is difficult to estimate the effects of vegetation on slope stability because of variations in plant species and environmental ***,influences of plant growth on slope stability change with time,resulting in changes in the safety *** study was conducted to evaluate the stability of vegetated slopes with time and investigate the effects of different layouts of plant species on slope ***,we used a plant growth model and slope stability analysis to build an evaluation *** accomplish this,one species of tree,shrub and grass was chosen to set six layout patterns.A slope with no vegetation served as a *** safety factors of the seven slopes were then calculated using the developed evaluation model and differences in the safety factors of slopes were compared and *** slope vegetated with Platycladus orientalis reached the most stable state at the age of 60 *** slope(Vitex negundo)had the maximum safety factor after 20 ***,the safety factor of vegetated slopes increased from 12.1%to 49.6% compared to the slope with no *** wind force was considered,the safety factor value of the slope changed from 3.5%to 43.5%.Vegetation mixtures of trees and grasses resulted in the best slope *** grasses on slopes can improve slope stability of trees to a greater degree than that of slopes with shrubs in the early stage of growth.

关键词： plant growth model Vegetated slope Slope stability Safety factor

Review and evaluation of cold recycling with bitumen emulsion and cement for rehabilitation of old pavements

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Journal of Traffic and transportation Engineering(English Edition) 2019年第4期6卷 311-323页

作者： Bohdan Dolzycki Piotr Jaskula Department of Highway and transportation Engineering Gdansk University of Technology

The article presents Polish experience with cold recycling of asphalt pavements with the usage of bituminous emulsion and cement. In the 1990 s numerous roads in Poland required immediate reinforcement due to their significant degradation. Implementation of the cold recycling technology was one of the solutions to this problem. Cold recycled mixtures contain e beside the recycled asphalt pavement and aggregate e two different types of binding agents: bituminous emulsion and Portland cement. First Polish requirements were developed in the 1990 s and were based on the Marshall test. After several years of application of these requirements, numerous transverse cracks appeared on the pavements. Field investigation showed that the frequency of transverse cracking was not uniform on all evaluated sections and that the growth rate of the number of cracks was decreasing. The main reason of extensive cracking was the overly high amount of the Portland cement and insufficient amount of the bituminous emulsion. This led to production of very stiff mixtures, with dominance of hydraulic bonds, which behaved similarly to cement-treated mixtures. The idea of flexible cold recycled base course was not utilized. This experience motivated the Polish Road Administration to develop new requirements. Second part of the article presents the new requirements for cold *** test methods as well as requirements concerning resistance to frost and water action were introduced in 2013. Implementing of the new requirements resulted in significant reduction in stiffness of the MCE mixtures. Values of stiffness modulus are even three times lower, which should significantly decrease the amount of potential reflective cracks on the pavement surface. Presently two types of technology of cold recycling are used in Poland, in-place and in-plant.

关键词： Cold recycling Mineral-cement-emulsion mixtures(MCE) Reflecting cracks Stiffness modulus Road reconstruction Fatigue life of pavement structures

Multi-objective optimization of high-sulfur natural gas purif ication plant

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Petroleum Science 2019年第6期16卷 1430-1441页

作者： Jian-Feng Shang Zhong-Li Ji Min Qiu Li-Min Ma College of Mechanical and transportation Engineering China University of PetroleumBeijing 102249China Beijing Key Laboratory of Process Fluid Filtration and Separation Beijing 102249China Natural Gas Processing plant of Sinopec Zhongyuan Oilfi eld Branch Puyang 457061China

There exists large space to save energy of high-sulfur natural gas purification *** multi-objective optimization problem has been investigated to effectively reduce the total comprehensive energy consumption and further improve the production rate of purified gas.A steady-state simulation model of high-sulfur natural gas purification process has been set up by using *** key operating parameters of the purification process have been determined based on the analysis of comprehensive energy consumption *** solve the problem that the process model does not converge in some conditions,back-propagation(BP)neural network has been applied to substitute the simulation model to predict the relative parameters in the optimization *** uniform design method and the table U21(107)have been applied to design the experiment points for training and testing BP *** prediction accuracy can be achieved by using the BP *** sorting genetic algorithm-II has been developed to optimize the two objectives,and 100 Pareto optimal solutions have been *** optimal points have been selected and evaluated *** results demonstrate that the total comprehensive energy consumption is reduced by 13.4%and the production rate of purified gas is improved by 0.2%under the optimized operating conditions.

关键词： High-sulfur natural gas purifi cation plant Multi-objective optimization Process simulation model Thermodynamic analysis BP neural network Genetic algorithm

Liquid–liquid extraction of levulinic acid from aqueous solutions using hydrophobic tri-n-octylamine/alcohol-based deep eutectic solvent

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Chinese Journal of Chemical Engineering 2023年第2期54卷 248-256页

作者： Yinglin Mai Xiaoling Xian Lei Hu Xiaodong Zhang Xiaojie Zheng Shunhui Tao Xiaoqing Lin School of Chemical Engineering and Light Industry Guangdong University of TechnologyGuangzhou 510006China Guangdong Provincial Key Laboratory of plant Resources Biorefinery Guangdong University of TechnologyGuangzhou 510006China Guangzhou Key Laboratory of Clean transportation Energy Chemistry Guangdong University of TechnologyGuangzhou 510006China

Levulinic acid(LA)is one of the top-12 most promising biomass-based platform chemicals,which has a wide range of applications in a variety of ***,separation and purification of LA from aqueous solution or actual hydrolysate continues to be a *** various downstream separation technologies,liquid-liquid extraction is a low-cost,effective,and simple process to separate *** key breakthrough lies in the development of extractants with high extraction efficiency,good hydrophobicity,and low *** this work,three hydrophobic deep eutectic solvents(DESs)based on tri-n-octylamine(TOA)as hydrogen bond acceptor(HBA)and alcohols(butanol,2-octanol,and menthol)as hydrogen bond donors(HBDs)were developed to extract LA from aqueous *** molar ratios of HBD and HBA,extraction temperature,contact time,solution pH,and initial LA concentration,DES/water volume ratios were systematically *** with 2-octanol-TOA and menthol-TOA DES,the butanol-TOA DES exhibited the superior extraction performance for LA,with a maximum extraction efficiency of 95.79±1.4%.Moreover,the solution pH had a great impact on the LA extraction efficiency of butanol-TOA(molar ratio=3:1).It is worth noting that the extraction equilibrium time was less than 0.5 *** importantly,the butanol-TOA(3:1)DES possesses good extraction abilities for low,medium,and high concentrations of LA.

关键词： Extraction Separation Levulinic acid Deep eutectic solvents Hydrophobic Aqueous solution

Optimal Percentage of Reclaimed Asphalt Pavement in Central plant Hot Recycling Mixture

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Journal of Wuhan University of Technology(Materials Science) 2010年第4期25卷 659-662页

作者：于新 Hohai University College of Civil and Transportation Engineering

For determining the optimal percentage of RAP material in central plant hot recycling, binder was recovered from RAP by means of Abson recovery method, and properties tests of mixed binders consisting of recovered asphalt and fresh asphalt at different ratios were performed. In addition, the performances of mixture with different percentages of RAP such as rutting resistance, anti-cracking, moisture susceptibility and fatigue resistance were tested. The binder test results showed that the high temperature performance was improved with the increase of the percentage of the RAP, while the low temperature performance was declined. When the percentage of the recovered binder was less than 30%, the mixed binder could match the technical standards for fresh asphalt. Tests on the mixtures showed that rutting resistance increased gradually as RAP percentage increased, while thermal anti-cracking at low temperature and fatigue properties declined. The effect of the percentage of RAP on moisture susceptibility was limited. It is indicated that low temperature performance and fatigue properties are important for selecting the optimal percentage of RAP. Based on data obtained from binders and mixtures, it is concluded that the maximum percentage of RAP is approximately 30% without the addition of rejuvenating agent.

关键词： central plant recycling RAP optimal percentage anti-cracking fatigue

Production of linear alkylbenzene over Ce containing Beta zeolites

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Chinese Journal of Chemical Engineering 2024年第3期67卷 220-227页

作者： Shiqi Zhang Shengzhi Gan Baoyu Liu Jinxiang Dong School of Chemical Engineering and Light Industry Guangdong Provincial Key Laboratory of Plant Resources BiorefineryGuangzhou Key Laboratory of Clean Transportation Energy ChemistryGuangdong University of TechnologyGuangzhou 510006China Jieyang Branch of Chemistry and Chemical Engineering Guangdong Laboratory(Rongjiang Laboratory) Jieyang 515200China

Ce-encapsulated Beta zeolite was synthesized by a one-pot hydrothermal method with citric acid complexing Ce in the absence of Na *** citric acid can effectively prevent the deposition of Ce species during the hydrothermal synthesis of zeolites,leading to uniform distribution of Ce cluster in the framework of Beta ***,the sodium-free synthesis system resulted that the Brønsted acid sites were mainly located on the straight channels and external surface of Beta zeolites,improving the utilization of Brønsted acid *** addition,Ce encapsulated Beta zeolites showed enhanced activity and robust stability in the alkylation of benzene with 1-dodecene based on the synergistic effect between Ce species and Brønsted acid sites,which pave the way for its practical application in the production of alkylbenzene.

关键词： Beta zeolites Catalysis Alkylation Long-chain olefins

Fabricating amide functional group modified hyper-cross-linked adsorption resin with enhanced adsorption and recognition performance for 5-hydroxymethylfurfural adsorption via simple one-step

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Chinese Journal of Chemical Engineering 2022年第3期35卷 230-239页

作者： Lei Hu Shunhui Tao Junting Xian Xiaodong Zhang Yao Liu Xiaojie Zheng Xiaoqing Lin School of Chemical Engineering and Light Industry Guangdong University of TechnologyGuangzhou 510006China Guangdong Provincial Key Laboratory of plant Resources Biorefinery Guangdong University of TechnologyGuangzhou 510006China Guangzhou Key Laboratory of Clean transportation Energy Chemistry Guangdong University of TechnologyGuangzhou 510006China

In this study,three kinds of amide functional group modified hyper-cross-linked adsorption resin were synthesized by alternating radical copolymerization in simple one-step and applied for 5-hydroxymethylfurfural(5-HMF)*** successful synthesis and properties of adsorbents were evaluated with Fourier transform infrared spectroscopy,scanning electron microscopy,nitrogen adsorption-desorption isotherms,thermogravimetric analysis,and elemental ***(N,N’-4,4’-diphenyl methane-bismaleimide-alt-divinylbenzene)(poly(BDM-alt-DVB))resin exhibited highest adsorption capacity for 5-HMF(64.0 mg·g^(-1)wet resin)and excellent adsorption selectivity(a_(5-HMF/LA)=2.71±0.12,α_(5-HMF/FA)=13.88±0.15,α_(5-HMF/Glucose)=11.91±1.11)in the multi-component solution at 25℃.Langmuir isotherm model well fitted the equilibrium adsorption data within the initial 5-HMF concentration range of 0.5-10.0 g·L^(-1) with highest correlation ***,the thermodynamic parameters demonstrated that the adsorption of 5-HMF onto poly(BDM-alt-DVB)resin was spontaneous and *** study revealed that the adsorption process was fast,reaching equilibrium within12 ***,the poly(BDM-alt-DVB)resin also demonstrated excellent *** summary,the poly(BDM-alt-DVB)resin will be useful in 5-HMF hydrolysate separation applications.

关键词： Adsorption 5-Hydroxymethylfurfural Isotherm Thermodynamics Kinetics Mechanism

Prediction Model of Refined Gasoline Blending Formula Based on PSO-DBN

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China Petroleum Processing & Petrochemical Technology 2022年第3期24卷 128-138页

作者： Wang Xiaoming Li Wei Li Yajie Jiang Dongnian Liang Chenglong School of Future Techrology South China University of TechnologyGuangzhou 510641 Pengcheng Laboratory Shenzhen 518000 College of Electrical and Information Engineering Lanzhou University of TechnologyLanzhou730050 Oil Storage and transportation plant PetroChina Lanzhou Petrochemical CompanyLanzhou730060

To address the problem of the low accuracy of refined gasoline blending formula in the petrochemical industry,the advantages of deep belief networks(DBNs)in feature extraction and nonlinear processing are considered,and they are applied to the prediction modeling of refined gasoline blending conservative ***,based on historical measured data of refined gasoline blending and according to the characteristics of the data set,we use bootstrapping to divide the training data set and the test data ***,considering that parameter selection for the network is difficult,particle swarm optimization is adopted to improve the related optimal parameters and replace the tedious process of manually selecting parameters,greatly improving optimization *** addition,the contrastive divergence algorithm is used for unsupervised forward feature learning and supervised reverse fine-tuning of the network,so as to construct a more accurate prediction model for conservative ***,in order to evaluate the effectiveness of this method,the simulation results are compared with those of traditional modeling methods,which show that the DBNs has better prediction performance than error back propagation and support vector machines,and can provide production guidance for refined gasoline blending formula.

关键词： formulation prediction deep belief network contrastive divergence particle swarm optimization