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Modeling and analysis of air combustion and steam regeneration in methanol to olefins processes

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Chinese Journal of Chemical Engineering 2024年第2期66卷 94-103页

作者： Jinqiang liang Danzhu Liu Shuliang Xu mao Ye Department of Chemical Physics University of Science and Technology of ChinaHefei 230026China National Engineering Research Center of Lower-Carbon Catalysis Technology Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116021China University of Chinese Academy of Sciences Beijing 100049China

Light olefins is the incredibly important materials in chemical *** to olefins(MTO),which provides a non-oil route for light olefins production,received considerable attention in the past ***,the catalyst deactivation is an inevitable feature in MTO processes,and regeneration,therefore,is one of the key steps in industrial MTO *** the MTO catalyst is regenerated by removing the deposited coke via air combustion,which unavoidably transforms coke into carbon dioxide and reduces the carbon utilization *** study shows that the coke species over MTO catalyst can be regenerated via steam,which can promote the light olefins yield as the deactivated coke species can be essentially transferred to industrially useful synthesis gas,is a promising pathway for further MTO processes *** this work,we modelled and analyzed these two MTO regeneration methods in terms of carbon utilization efficiency and technology *** shown,the steam regeneration could achieve a carbon utilization efficiency of 84.31%,compared to 74.74%for air combustion *** MTO processes using steam regeneration can essentially achieve the near-zero carbon *** addition,light olefins production of the MTO processes using steam regeneration is 12.81%higher than that using air combustion *** this regard,steam regeneration could be considered as a potential yet promising regeneration method for further MTO processes,showing not only great environmental benefits but also competitive economic performance.

关键词： Model Methanol to olefins Regeneration Greenhouse gas Processes simulation

Probabilistic-Ellipsoid Hybrid Reliability Multi-Material Topology Optimization Method Based on Stress Constraint

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 757-792页

作者： Zibin mao Qinghai Zhao liang Zhang College of Mechanical and Electrical Engineering Qingdao UniversityQingdao266071China National Engineering Research Center for Intelligent Electrical Vehicle Power System Qingdao UniversityQingdao266071China

This paper proposes a multi-material topology optimization method based on the hybrid reliability of the probability-ellipsoid model with stress constraint for the stochastic uncertainty and epistemic uncertainty of mechanical loads in optimization *** probabilistic model is combined with the ellipsoidal model to describe the uncertainty of mechanical *** topology optimization formula is combined with the ordered solid isotropic material with penalization(ordered-SIMP)multi-material interpolation *** stresses of all elements are integrated into a global stress measurement that approximates the maximum stress using the normalized p-norm ***,the sequential optimization and reliability assessment(SORA)is applied to transform the original uncertainty optimization problem into an equivalent deterministic topology optimization(DTO)*** response surface and sparse grid technique are combined with SORA to get accurate information on the most probable failure point(MPP).In each cycle,the equivalent topology optimization formula is updated according to the MPP information obtained in the previous *** adjoint variable method is used for deriving the sensitivity of the stress constraint and the moving asymptote method(MMA)is used to update design ***,the validity and feasibility of the method are verified by the numerical example of L-shape beam design,T-shape structure design,steering knuckle,and 3D T-shaped beam.

关键词： Stress constraint probabilistic-ellipsoid hybrid topology optimization reliability analysis multi-material design

On a Flexible Loan Repayment Method Depending on Borrower's Asset with an Early Termination Clause

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 557-567页

作者： Jin liang Jia-qi mao Zhao-ya LIU School of Mathematical Sciences Tongji UniversityShanghai 200092China

Aiming at the problem that the asset’s fluctuation influences the borrower’s repayment ability,a loan with a new and flexible repayment method is designed,which depends on the asset value of the *** repayment method can reduce the loan default probability,but it causes the uncertainty of the pay off *** the repayment term is related to the regular repayment amount in this method,a boundary for the regular repayment amount is set up in order to avoid too long repayment *** will balance the benefit of borrowers and lenders and improve the applicability of this *** establishing a mathematical model of the residual value of the loan,this model can be transformed into an initial-boundary problem of a partial differential *** analytic solution and the expected time to pay off the loan are ***,numerical analysis are shown.

关键词： flexible repayment method repayment ratio early termination clause expected pay off time

Shock-induced chemical reaction characteristics of PTFE-Al-Bi_(2)O_(3)reactive materials

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Defence Technology（防务技术） 2024年第6期36卷 1-12页

作者： Chunlan Jiang Rong Hu Jingbo Zhang Zaicheng Wang liang mao State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

A ternary system of PTFE/Al/Bi_(2)O_(3)is constructed by incorporating PTFE-based reactive material and thermite for enhancing the energy release of the PTFE-based reactive *** effects of Bi_(2)O_(3)in the PTFE/Al/Bi_(2)O_(3)on both mechanical properties and the energy release were investigated through various tests such as thermogravimetry-differential scanning calorimetry,adiabatic oxygen bomb test and split Hopkinson pressure bar *** microstructure observed through scanning electron microscope and Xray diffraction results are used to analyze the ignition and reaction mechanism of PTFE/Al/Bi_(2)O_(3).The results indicate that the PTFE/Al/Bi_(2)O_(3)are capable of triggering the exothermic reaction of molten PTFE/Bi_(2)O_(3)and Al/Bi_(2)O_(3)over the PTFE/Al reactive materials,thereby promoting *** excessive aluminum in the ternary system is beneficial for increasing energy *** ignition of shock-induced chemical reactions in PTFE/Al/Bi_(2)O_(3)is closely related to the material *** dominant mechanism for hot-spot generation under Split Hopkinson Pressure Bar test is the frictional temperature rise at the microcrack after failure.

关键词： PTFE/Al/Bi_(2)O_(3) Shock-induced chemical reaction Energy release

Stereoselective synthesis of substituted 1,3-dienes from propargylic esters: electrophilic-metal or redox catalysis?

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Science China Chemistry 2024年第5期67卷 1384-1396页

作者： Mengfu Dai liangliang song liang-An Chen Jiangsu Collaborative Innovation Center of Biomedical Functional Materials Jiangsu Key Laboratory of New Power BatteriesSchool of Chemistry and Materials ScienceNanjing Normal UniversityNanjing 210023China Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources International Innovation Center for Forest Chemicals and MaterialsCollege of Chemical EngineeringNanjing Forestry UniversityNanjing 210037China

1,3-Diene architectures are not only widely present in natural products, pharmaceuticals, and functional organic materials but also serve as versatile building blocks to furnish important functionalized molecules in synthetic chemistry due to conjugated repeating C=C units. Accordingly, various strategies to access substituted 1,3-dienes in a stereoselective manner have been developed. However, chemo-, regio-and stereoselective synthesis of highly substituted 1,3-dienes still remains elusive and challenging. Readily available propargylic esters have emerged as an appealing class of synthetic intermediates for accessing functionalized 1,3-dienes, especially challenging tri-or tetrasubstituted variants, via transition-metal catalysis, including electrophilic metal and redox neutral catalysis. This review, for the first time, systematically highlights recent advances in transitionmetal catalyzed synthesis of substituted 1,3-dienes from propargylic esters, discusses the mechanisms and synthetic utilities, and gives the remaining challenges and potential opportunities in this field.

关键词： 1 3-diene propargylic ester Lewis acid redox catalysis transition metal

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Effects of Sb Content on Solidification Pathways and Grain Size of AZ91 Magnesium Alloy

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Acta Metallurgica Sinica(English Letters) 2015年第1期28卷 115-121页

作者： Dan-Hui Hou song-mao liang Rong-Shi Chen Chuang Dong En-Hou Han School of Material Science and Engineering Dalian University of Technology Institute of Metal Research Chinese Academy of Science Institute of Metallurgy Clausthal University of Technology

The phase constitution and solidification pathways of AZ91＋xSb（x = 0, 0.1, 0.5, 1, in wt%） alloys were investigated through ways of microstructure observation, thermal analysis technique, and thermodynamic calculation. It was found that the non-equilibrium solidification microstructure of AZ91＋xSb（x = 0.1, 0.5, 1） is composed of a-Mg matrix, b-Mg17Al12 phase, and intermetallic compound Mg3Sb2. The grain size of the alloys with different Sb contents was quantitatively determined by electron backscattered diffraction technique which shows no grain refinement in Sb-containing AZ91 alloy. Thermodynamic calculations are in reasonable agreement with thermal analysis results, showing that the Mg3Sb2 phase forms after a-Mg nucleation, thus impossible acts as heterogeneous nucleus for a-Mg dendrite. Besides,the solid fraction at dendrite coherency point（fDCPs） determined from thermal analysis decreases slightly with increasing Sb content, which is consistent with the fact that Sb does not refine the grain size of AZ91 alloy.

关键词： Mg–Al–Zn–Sb alloy Solidification pathways Nucleation Grain size Dendrite coherency

Fine-grained grid computing model for Wi-Fi indoor localization in complex environments

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Journal of Electronic Science and Technology 2024年第1期22卷 42-52页

作者： Yan liang song Chen Xin Dong Tu Liu School of Computer Engineering Chengdu Technological UniversityChengdu611730China HAN Networks Corporation Limited Beijing100094China

The fingerprinting-based approach using the wireless local area network(WLAN)is widely used for indoor ***,the construction of the fingerprint database is quite *** when the position of the access point(AP)or wall changes,updating the fingerprint database in real-time is *** appropriate indoor localization approach,which has a low implementation cost,excellent real-time performance,and high localization accuracy and fully considers complex indoor environment factors,is preferred in location-based services(LBSs)*** this paper,we proposed a fine-grained grid computing(FGGC)model to achieve decimeter-level localization *** points(RPs)are generated in the grid by the FGGC ***,the received signal strength(RSS)values at each RP are calculated with the attenuation factors,such as the frequency band,three-dimensional propagation distance,and walls in complex *** a result,the fingerprint database can be established automatically without manual measurement,and the efficiency and cost that the FGGC model takes for the fingerprint database are superior to previous *** proposed indoor localization approach,which estimates the position step by step from the approximate grid location to the fine-grained location,can achieve higher real-time performance and localization accuracy *** mean error of the proposed model is 0.36 m,far lower than that of previous ***,the proposed model is feasible to improve the efficiency and accuracy of Wi-Fi indoor *** also shows high-accuracy performance with a fast running speed even under a large-size *** results indicate that the proposed method can also be suitable for precise marketing,indoor navigation,and emergency rescue.

关键词： Fine-grained grid computing (FGGC) Indoor localization Path loss Random forest Reference points(RPs)

Surfactant-assisted crystallization of lysozyme and its mechanism

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Particuology 2024年第7期90卷 199-208页

作者： Yujie song Rongfei Ren Min Su Zhihan liang Qi Hao School of Chemical Engineering Hebei University of TechnologyTianjin 300130China

Surfactants were used to assist in the crystallization of *** types of surfactants with different structures(sodium dodecyl sulfate,cetyltrimethylammonium bromide,or betaine hydrochloride[BH])were *** study indicated that three surfactants were all capable of shortening the crystallization induction time of lysozyme,with BH inducing the shortest crystallization induction time(t=1 min)and the largest crystal size(37μm).The molecular interactions among each of the three surfactants aforementioned and lysozyme were also investigated by *** was found that hydrogen bonding dominantly acted between the carboxyl structure of the surfactant BH and the lysozyme,which produced the most favorable conformation for the self-assembly of lysozyme(promote lysozyme orderly aggregation and shorten the crystallization induction time).On this basis,the mechanism of surfactant-promoted lysozyme crystallization was proposed.

关键词： Protein Crystallization Surfactant Lysozyme Molecular interaction Mechanism

Milk fat globule membrane supplementation protects againstβ-lactoglobul-ininduced food allergy in mice via upregulation of regulatory T cells and enhancement of intestinal barrier in a microbiota-derived short-chain fatty acids manner

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Food Science and Human Wellness 2024年第1期13卷 124-136页

作者： Han Gong Tiange Li Dong liang Jingxin Gao Xiaohan Liu Xueying mao Key Laboratory of Functional Dairy Ministry of EducationCollege of Food Science and Nutritional EngineeringChina Agricultural UniversityBeijing 100083China Henan Engineering Technology Research Center of Food Processing and Circulation Safety Control College of Food Science and TechnologyHenan Agricultural UniversityZhengzhou 450002China Applied Nutrition I China National Center for Food Safety Risk AssessmentBeijing 100022China

Milk fat globule membrane(MFGM),which contains abundant glycoproteins and phospholipids,exerts beneficial effects on intestinal health and *** aim of this study was to evaluate the protective effects and possible underlying mechanisms of MFGM on cow’s milk allergy(CMA)in aβ-lactoglobulin(BLG)-induced allergic mice *** was supplemented to allergic mice induced by BLG at a dose of 400 mg/kg body *** demonstrated that MFGM alleviated food allergy symptoms,decreased serum levels of lipopolysaccharide,pro-inflammatory cytokines,immunoglobulin(Ig)E,Ig G1,and Th2 cytokines including interleukin(IL)-4,while increased serum levels of Th1 cytokines including interferon-γand regulatory T cells(Tregs)cytokines including IL-10 and transforming growth factor-β.MFGM modulated gut microbiota and enhanced intestinal barrier of BLG-allergic mice,as evidenced by decreased relative abundance of Desulfobacterota,Rikenellaceae,Lachnospiraceae,and Desulfovibrionaceae,while increased relative abundance of Bacteroidetes,Lactobacillaceae and Muribaculaceae,and enhanced expressions of tight junction proteins including Occludin,Claudin-1 and zonula ***,MFGM increased fecal short-chain fatty acids(SCFAs)levels,which elevated G protein-coupled receptor(GPR)43 and GPR109A *** increased expressions of GPR43 and GPR109A induced CD103+dendritic cells accumulation and promoted Tregs differentiation in mesenteric lymph node to a certain *** summary,MFGM alleviated CMA in a BLG-induced allergic mice model through enhancing intestinal barrier and promoting Tregs differentiation,which may be correlated with SCFAs-mediated activation of *** findings suggest that MFGM may be useful as a promising functional ingredient against CMA.

关键词： Cow’s milk allergy Milk fat globule membrane Gut microbiota Short-chain fatty acid G protein-coupled receptor Regulatory T cell