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Journal of Applied Mathematics and Physics 2017年第7期5卷 1411-1423页

作者： Souleymanou Abbagari Hamadou Halidou Thomas B. Bouetou Timoleon C. Kofane department of Basic Science Law and Humanities Institute of Mines and Petroleum Industries University of Maroua Maroua Cameroon Laboratory of Mechanics Materials and Structures Department of physics University of Yaounde I Yaounde Cameroon National Advanced School of engineering University of Yaounde I Yaounde Cameroon Centre d’Excellence en Technologies de l’Information et de la Communication (CETIC) University of Yaounde I Yaounde Cameroon

In this paper, we investigate the Gross-Pitaevskii (GP) equation which describes the propagation of an electron plasma wave packet with a large wavelength and small amplitude in a medium with a parabolic density and constant interactional damping by the Covariant Prolongation Structure Theory. As a result, we obtain general forms of Lax-Pair representations. In addition, some hidden structural symmetries that govern the dynamics of the GP equation such as SL(2,R), SL(2,C), Virasoro algebra, SU(1,1) and SU(2) are unearthed. Using the Riccati form of the linear eigenvalue problem, infinite number of conservation laws of the GP equation is explicitly constructed and the exact analytical soliton solutions are obtained by employing the simple and straightforward Hirota’s bilinear method.

关键词： Gross-Pitaevskii Equation Covariant Prolongation Structure Theory Hidden Structural Symmetries Hirota’s Bilinear Method

Preparation of hollow mesoporous silica nanorods for encapsulating and slowly releasing eugenol

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Chinese Chemical Letters 2020年第12期31卷 3135-3138页

作者： Tianlu Zhang Zhiguo Lu Luyao Zhang Yan Li Jun Yang Jie Shen Jianze Wang Yunwei Niu Zuobing Xiao Lei Chen Xin Zhang State Key Laboratory of Biochemical engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China department of Obstetrics and Gynecology Navy General Hospital of People Liberation ArmyBeijing 100048China School of Chemical engineering University of Chinese Academy of SciencesBeijing 100049China Shanghai Research Institute of Fragrance and Flavor Industry Shanghai 200232China School of Perfume and Aroma Technology Shanghai Institute of TechnologyShanghai 200233China

Fragrances are widely used in many aspects of our *** cannot only make people happy,but also treat many ***,excessively fast evaporation rate is one of the main obstacles to the use of *** this study,mesoporous silica nanorods(MSNRs)and hollow mesoporous silica nanorods(HMSNRs)were prepared to encapsulate *** two nano-fragrances were named eugenol@MSNRs and eugenol@HMSNRs,*** morphologies,size,interior structures and pore performances of MSNRs and ***,the performances of encapsulation and fragrance release of eugenol@MSNRs and eugenol@HMSNRs were compared and *** results showed that eugenol@HMSNRs encapsulated more fragrance and were faster to encapsulate compared with eugenol@*** the release rates of eugenol from eugenol@MSNRs and eugenol@HMSNRs were *** the eugenol was released from eugenol@MSNRs more slowly.

关键词： Eugenol Hollow mesoporous silica nanorods Mesoporous silica nanorods Nano-fragrance Slow release of fragrance

Microstructural analysis of organic matter in shale by SAXS and WAXS methods

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Petroleum Science 2022年第3期19卷 979-989页

作者： Kou-Qi Liu Zhi-Jun Jin Lian-Bo Zeng Meng-Di Sun Bo Liu Ho Won Jang Majid Safaei-Farouji Mohammadreza Shokouhimer Mehdi Ostadhassan Institute of Energy Peking UniversityBeijing100871China State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China State Key Laboratory of Continental Shale Accumulation and Efficient Development Ministry of EducationNortheast Petroleum UniversityDaqingHeilongjiang 163318China department of Materials Science and engineering Research Institute of Advanced MaterialsSeoul National UniversitySeoul08826Republic of Korea School of Geology College of ScienceUniversity of TehranTehranIran department of Materials Science and engineering Seoul National UniversitySeoul08826Republic of Korea department of Geology Ferdowsi University of MashhadMashhadIran

Characterizing the kerogen-hosted pore structures is essential to understand the adsorption,transport and storage potential in organic-rich shale *** this paper,we first separated the organic matter(kerogen)from the mineral matrix in four different shale samples of the Bakken Formation with different thermal maturities and then analyzed their chemical compositions using the wide-angle X-ray scattering(WAXS)***,we acquired small-angle X-ray scattering(SAXS)to characterize the structure of the organic matter and see how these two will *** WAXS results showed that the isolated kerogens have high purity(free of inorganic minerals)and retain different chemical ***,SAXS analysis revealed that the isolated kerogens have similar radius of gyration(R_(g))which is around 90Åand the molecules are in the compact *** on the pore size distribution analysis from the SAXS data,two main peaks were found in all of these four samples with one peak less than 40Åand the other one larger than 1000Å.Also,the TEM images revealed that Sample 1 is abundant in pores with sizes around 20 nm while Sample 2 does not have pores of that size,which agrees with the results from the pore size distribution that was obtained from the SAXS ***,this study exhibits how different analytical instruments can provide us with useful information from complex structures of geomaterials.

关键词： Isolated kerogen Bakken shale SAXS WAXS Pore structures

带区间参数的外部分数阶黏弹性阻尼器控制结构的可靠性分析

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Acta Mechanica Sinica 2023年第4期39卷 97-108页

作者： Alba Sofi Giuseppe Muscolino Mario Di Paola department of Architecture and Territory and Inter-University Centre of Theoretical and Experimental Dynamics University“Mediterranea”of Reggio CalabriaReggio Calabria89124Italy department of engineering and Inter-University Centre of Theoretical and Experimental Dynamics University of MessinaMessina89166Italy department of engineering University of PalermoPalermo90128Italy

本文研究了性质不确定的外黏弹性阻尼器控制结构的抗震性能.耗能器件的行为由分数阶本构律描述,其中分数阶导数阶和阻尼系数都被建模为具有指定下界和上界的区间变量.地震动加速度是一个零均值平稳高斯随机过程.在这些假设下,被控结构... 详细信息

本文研究了性质不确定的外黏弹性阻尼器控制结构的抗震性能.耗能器件的行为由分数阶本构律描述,其中分数阶导数阶和阻尼系数都被建模为具有指定下界和上界的区间变量.地震动加速度是一个零均值平稳高斯随机过程.在这些假设下,被控结构的运动由一组区间分数阶微分方程控制.所有响应量均由区间零均值平稳高斯随机过程描述,其功率谱密度函数依赖于黏弹性器件的区间参数,在频域上完全表征.通过将经典的首通道问题扩展到区间框架进行可靠性分析.用一种有效的近似方法计算了区间值可靠度函数的边界.本文给出了基于文献中实验结果定义的间隔特性的黏弹性器件的实例研究.

关键词：功率谱密度函数随机过程区间参数分数阶导数零均值黏弹性阻尼器区间变量分数阶微分方程

Timber-concrete composite bridges:Three case studies

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Journal of Traffic and Transportation engineering(English Edition) 2018年第6期5卷 429-438页

作者： Massimo Fragiacomo Amedeo Gregori Junqing Xue Cristoforo Demartino Matteo Toso department of Civil Construction-Architectural and Environmental F.ngineeringUniversity of L'AquilaL'Aquila 67200Italy College of Civil engineering Fuzhou UniversityFuzhou 350108China College of Civil engineering Nanfling Tech UniversityNanjing 210800China Maffeis engineering Solagna 36020Italy

During the last years, timber-concrete composite(TCC) structures have been extensively used in Europe both in new and existing buildings. Generally speaking, a composite structure combines the advantages of both materials employed: the strength and stiffness of the concrete in compression and the tensile strength, lightweight, low embodied energy, and aesthetical appearance of the timber. The concrete slab provides protection of the timber beams from direct contact with water, which is crucial to ensure the durability of the timber beams, particularly when used for bridges. Different types of connectors can be used to provide force exchange between the concrete slab and the timber beam. The choice of a structurally effective yet cheap shear connection between the concrete topping and the timber joist is crucial to make the TCC structures a viable solution that can compete with reinforced concrete and steel structures. In this paper, the possibilities offered by TCC structures for short-span bridge decks are discussed. The technology of TCC structures and the general design rules are illustrated. Three case studies are reported, including a short-span bridge tested in Colorado, USA, with the timber layer being constructed from recycled utility poles and notch connection; a TCC bridge with glulam beams and triangular notches with epoxyglued rebar connectors built in Portugal; and a TCC bridge with glulam beams and rectangular notches built in Germany. All the solutions were found to be structurally effective and aesthetically pleasing. They can all provide a sustainable option for short-span bridges.

关键词： Timber-concrete composite Bridge Design Connection system

A micro–macro constitutive model for rock considering breakage effects

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International Journal of Mining Science and Technology 2023年第2期33卷 173-184页

作者： Di Yu Enlong Liu Bo Xiang Yunyong He Fei Luo Chuan He State Key Laboratory of Hydraulics and Mountain River engineering College of Water Resource and HydropowerSichuan UniversityChengdu 610065China b Institute for Disaster Management and Reconstruction Sichuan UniversityChengdu 610207China Highway Planning Survey and Design Research InstituteSichuan Provincial Transport DepartmentChengdu 610041China College of Civil engineering Sichuan Agricultural UniversityChengdu 611830China

The paper proposes a three-scale binary medium-based constitutive model on the basis of the meso structures and micro components to describe the elasto-plastic mechanical behavior of mudstone *** on the breakage mechanism of geomaterials,mudstone samples are considered as two different materials(bonded and frictional elements)at *** micro to meso scales,given the similar but different mineralogy composition and porosity of the bonded and frictional elements at microscale,as well as their separate mechanical characteristics,different homogenization methods are adopted to obtain their respective meso mechanical *** the mesoscale,in view of the unique meso structures and the continuous material transformation,the extended self-consistent scheme(SCS)is improved to be adaptable to elasto-plastic composites with varying meso *** the consideration of the evolution form of the breakage ratio under the external loading being given based on the assumed strength distribution of the meso bonded elements,the mechanical relations between meso and macro scales are ***,on the basis of the mean-field method and combined with the critical mechanical connections between different scales,the micro-meso-macro constitutive model for mudstone samples are *** model validation shows that,with a few model parameters,the proposed model can well reflect the stress and deformation features of mudstone samples with complex micro-components.

关键词： Micromechanics Binary-medium model Multiscale model Breakage mechanism Mudstone

Recent advances in breathable electronics

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Nano Research 2023年第3期16卷 4130-4142页

作者： Zhuocheng Yan Jian Xiong Bin Wang Min Gao Guangqiang Yin Tao Hu Taisong Pan Xinzhong Wang Yuan Lin department of Electronic Communication and Technology Shenzhen Institute of Information TechnologyShenzhen 518172China School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 610054China School of Information and Software engineering University of Electronic Science and Technology of ChinaChengdu 610054China engineering Cooperation on Applied Medicine Research Center University of Electronic Science and Technology of ChinaChengdu 610054China

The successful implementation of bioelectronic devices attached to living organism hinges on a number of material and device characteristics,including not only electrical and mechanical performances to gather physiological signals from living organism thus enabling status monitoring,but also permeability or breathability for gas/nutrient exchange between living organisms and surroundings to ensure minimum perturbation of the intrinsic biological ***,most bioelectronic devices built on planar polymeric substrates,such as polydimethylsiloxane(PDMS),polyurethane(PU),and polyimide(PI),lack efficient gas permeability,which may hinder the emission of volatile compounds from the surface of living organism,affecting the natural metabolism and reducing the comfort of ***,achieving permeability or breathability in bioelectronic devices is a significant ***,the devices made of gas-permeable materials with porous structures,that combine electronic components with daily garments,such as fibric and textile,offer exciting opportunities for breathable *** this review,several types of gas-permeable materials with their synthesis and processing routes are ***,two methods for measuring water vapor transmission rate of materials are discussed in ***,recent progress in the use of gaspermeable materials for the applications of plant-and skin-attached electronics is summarized systematically.

关键词： breathability gas permeability porous sponge foam nano materials plant electronics wearable electronics

Evaluating the blast mitigation performance of hard/soft composite structures through field explosion experiment and numerical analysis

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Acta Mechanica Sinica 2022年第1期38卷 27-36页

作者： Fengyuan Yang Zhijie Li Zhuo Zhuang Zhanli Liu Applied Mechanics Laboratory Department of Engineering MechanicsSchool of AerospaceTsinghua UniversityBeijing 100084China

The application of hard/soft composite structure in personnel armor for blast mitigation is relatively practical and effective in realistic protection engineering,such as the shell/liner system of the ***,there is still lacking a reliable experi-mental methodology to effectively evaluate the blast mitigation performance when the structure directly contacts the protected target,which limits the development of protection *** this paper,we proposed a new method to evaluate experi-mentally and numerically the blast mitigation performance of hard/soft composite *** blast mitigation mechanism is *** hard/soft structures were composed of ultra-high molecular weight polyethylene(UHMWPE)composite and expanded polyethylene(EPE)*** field explosion experiment,a 7.0 kg trinitrotoluene(TNT)spherical charge is used to generate blast waves at a 3.8 m stand-off distance.A pressure test device is designed to support the tested structure and measure the transmitted blast pressure pulses after passing through the *** results indicate that the hard/soft structures can mitigate the blast pressure pulse into the triangular pressure pulse,through making the pulse profile flatter,reducing the pressure amplitude,and delaying the pulse arrival ***,the combination of 7 mm UHMWPE composite and 20 mm EPE foam can reduce the blast pressure amplitude by 40%.Correspondingly,the finite element simulation is also carried out to understand the blast mitigation *** numerical results indicate that the regulation for blast pressure pulses mainly complete at the hard/soft interface,which is attributed to the reflection of pressure waves at the interface and the deformation of the soft layer compressed by the hard layer possessing kinetic ***,based on these analyses,the corresponding theoretical model is proposed,and it can well explain the experimental and numerical *** study is meaningful for e

关键词： Blast mitigation Composite structure Field explosion experiment Numerical simulation

Anisotropic stellar structures in the f(T)theory of gravity with quintessence via embedding approach

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Chinese Physics C 2021年第4期45卷 426-439页

作者： Allah Ditta Mushtaq Ahmad Ibrar Hussain G.Mustafa department of Mathematics COMSATS University IslamabadLabore CampusPakistan National University of Computer and Emerging Sciences Chiniot-Faisalabad CampusPakistan School of Electrical engineering and Computer Science National University of Sciences and TechnologyH-12IslanpabadPakistan department of Mathematics Shanghai UniversityShanghai 200444China

This work suggests a new model for anisotropic compact stars with quintessence in f(T)gravity by us-ing the off-diagonal tetrad and the power-law as f(T)=βT^(n),where T is the scalar torsion andβand n are real *** acquired field equations incorporating the anisotropic matter source along with the quintessence field,in f(T)gravity,are investigated by making use of the specific character of the scalar torsion T for the observed stars PSRJ1614-2230,***-3,EXO1785-248,and *** is suggested that all the stellar struc-tures under examination are advantageously independent of any central singularity and are *** graphical analysis shows that various physical features which are crucially important for the emergence of the stellar structures are conferred.

关键词： quintessence power-law model f(T)gravity anisotropic compact stars

Interaction between a diesel-fuel spray and entrained air with single- and double-injection strategies using large eddy simulations

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Propulsion and Power Research 2020年第1期9卷 37-50页

作者： Jonathan Brulatout François Garnier Patrice Seers Mechanical engineering department École de Technologie Supérieure1100 Notre-Dame Street WestMontrealH3C 1K3Canada

Interaction between fuel and air in a combustion chamber is one of the main drivers of the mixing ***,flow visualizations are limited by high droplet density in the ***,the ability of large eddy simulations(LES)to resolve large scales of flow offers good perspectives on capturing flow structures issued from the interaction between the Lagrangian(fuel droplets)and Eulerian(ambient gas)*** study examined these interactions first during a single injection using 3D and 2D criteria for both *** for the 3D criteria,the spray shape was analyzed in parallel to the Q-criteria applied to the Eulerian phase,making it possible to relate the spray deformations to some specific Eulerian ***,2D criteria were the fuel mass-fraction field and Eulerian streamlines,both taken in the mid-plane of the *** last analysis allows for identifying certain mechanisms involved in the Eulerian phase’s structure generation and relates it to high fuel-concentration areas in the fuel mass-fraction visualizations.

关键词： Diesel fuel spray Large eddy simulation Multiple injection Coherent structures Lagrangian-Eulerian interaction Air-spray interactions