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Total loads modeling and geological adaptability analysis for mixed soil-rock tunnel boring machines

Underground Space 2022年第3期7卷 337-351页

作者： Wencong Qi Lihui wang Siyang Zhou Yilan kang Qian zhang Key Laboratory of Modern Engineering Mechanics School of Mechanical EngineeringTianjin UniversityTianjin 300350China Department of Military Vehicle Academy of Military TransportationTianjin 300161China

Rock-soil interface mixed ground(RSI)is often encountered in tunnel *** excavation loads of tunnel boring machines(TBMs)are controlled by the interaction characteristics between TBM and rock/soil *** different properties of rock and soil cause the varying interaction range and stress ***,there have been several studies available to estimate excavation loads under RSI,and the conclusion is that the total loads increase with increasing the rock layer proportion in the excavation ***,the previous studies cannot take the difference of rock/soil properties into account,except for the calculation of cutters ***,the interaction characteristics between RSI and TBM is *** paper analyzes the interaction characteristics between TBM’s main components and complex geological conditions(e.g.,layered soil,layered rock,and RSI condition).A model is proposed to calculate the total thrust and total torque assuming quasi-static equilibrium of the tunneling *** rationality and applicability of the model are discussed and verified by two typical ***,the geological adaptability is discussed in terms of the excavation difficulty and the matching relationship between total torque and total *** results indicate that when the rock layer proportion in the excavation face increases,the reduction of overall extrusion and friction loads is 1.5 times higher than the increase of disc cutters breaking *** total loads and the ratio of the total torque to total thrust decrease approximately *** is a power function relationship between the excavation difficulty index and the penetration *** results of this study provide an important reference for the total loads design of equipment propulsion systems and the parameter adjustment during tunnel construction.

关键词： Rock-soil interface mixed ground Tunnel boring machine Total loads prediction Thrust and torque Geological adaptability analysis

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Hydrogen Bonding Assembled 3D Supramolecular Structures Formed by 5-Amino-2,4,6-triiodoisophthalic Acid and TV-Heterocyclic Aromatic Ligands

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Chemical Research in Chinese Universities 2019年第5期35卷 806-811页

作者： YU Wenli zhang Mingjuan LIU kang YANG Yu wang Lei Key Laboratory of Eco-chemical Engineering Ministry of EducationTaishan Scholar Advantage and Characteristic Discipline Team ofEco Chemical Process and TechnologyLaboratory of Inorganic Synthesis and Applied ChemistryCollege of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao 266042P.R.China

Three salts constructed by 5-amino-2,4,6-triiodoisophthalic acid(ATIPA) with N-heterocycles aromatic coformers such as pyridine tetrazolium, tetramethylpyraziiie and cyanuric acid were synthesized by slowing evaporation of solvent. X-Ray single crystal analysis shows that hydrogen protons of the carboxyl groups transfer to nitrogen atoms of the N-heterocyclic coformers to form N-H…0 hydrogen bonds in all the three compounds. A huge amount of H-bonds play significant role in tlie construction of these compounds and all of them generate 3D structures through strong O-H…N, O-H…O, N-H…O and weak C-H…O hydrogen bonds. Moreover, solvent water molecules are indispensable in the formation of compounds 1 and 3, which constitutes different supramolecular synthons to bridge individual molecules and chains to form stable structures. In addition, these crystal structures were further characterized by themiogravimetric analysis and infrared spectroscopy.

关键词： Hydrogen bond Supramolecular structure X-Ray diffraction N-Heterocyclic aromatic ligand

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Propane Aromatization over Mo/HZSM-5 Catalysts

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Journal of Natural Gas Chemistry 2002年第1期11卷 43-50页

作者： Junwei wang Maoqing kang Zhixin zhang Xinkui wang Institute of Coal Chemistry Chinese Academy of SciencesTaiyuan 030001China

Impregnation, mechanical mixing and hydrothermal treatment methods were used to introduce molybdenum species into the HZSM-5 zeolite. The structure and surface acidity of the catalysts were studied by means of XRD, FT-IR, NH3-TPD, TPR and XPS. The effects of Mo content and reaction time on stream on the aromatization of propane were investigated. It was found that the performance of the Mo/HZSM-5 catalyst prepared by the hydrothermal treatment method was much better than that of the other two catalysts. For example, under the reaction conditions of 823 K and 600 h-1, propane conversion and aromatics selectivity over the catalyst prepared by hydrothermal pretreatment could reach 89.17% and 78.56%, respectively. XRD and XPS results showed that the Mo species in the catalysts prepared by hydrothermal treatment were highly dispersed on the surface of the HZSM-5, and larger amounts of them could penetrate into the HZSM-5 channel, as compared with the other two kinds of catalysts. These factors may be responsible for their high activities for propane aromatization. IR and NH3-TPD studies indicated that the number of Bronsted acid centers decreased and the Lewis acid centers increased after Mo was introduced into the HZSM-5 zeolite.

关键词： Mo/HZSM-5 propane aromatization preparation hydrothermal treatment

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20 nm-ultra-thin fluorosiloxane interphase layer enables dendrite-free,fast-charging,and flexible aqueous zinc metal batteries

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Chinese Chemical Letters 2024年第12期35卷 550-556页

作者： Yuhuan Meng Long zhang Lequan wang Junming kang Hongbin Lu State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai 200438China School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China Yiwu Research Institute of Fudan University Yiwu 322000China

Dendrite growth of zinc(Zn)anode at high current density severely affects the fast-charging performance of aqueous zinc metal batteries(AZMBs).While interfacial modification strategies can optimize Zn per formance,challenges such as complicated preparation processes,excessive layer thicknesses,and high voltage hysteresis should be ***,we utilize a cost-effective liquid fluorosiloxane,(3,3,3trifluoropropyl)trimethoxysilane,for scalable modification of Zn foil via drop-casting at room tempera ture,resulting in an ultra-thin interphase layer of only 20 *** Si-O-Zn bonds formed between flu orosiloxane and Zn ensure interfacial stability,and the Si-O-Si bonds between fluorosiloxane molecule help to homogenize the electric field ***,the abundant highly electronegative flu orine atoms on the anode surface act as zincophilic sites,promoting the uniform deposition of Zn^(2+)Thus,the modified Zn foil(SiFO-Zn)exhibits excellent dendrite suppression,reduced voltage hysteresis and prolonged cycle life at ultra-high current density(40 mA/cm^(2)),achieving a cumulative areal capac ity of 12.9 Ah/cm^(2).Further,the full cell assembled with 10μm-thick Si FO-Zn anode and MnO_(2)cathode achieves 2600 cycles at 5 A/g with minimal capacity degradation,and a large-size(22.5 cm^(-2))pouch cel powers the light-emitting diode even after reverse bending,demonstrating the potential of AZMBs fo fast-charging flexible devices.

关键词： Siloxane High current density Zinc dendrite Fast-charging Flexible device

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A Comparison Study of Sensitivity on PJ and NPS Models in China Seas

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Journal of Ocean University of China 2019年第5期18卷 1022-1030页

作者： GUO Xiangming ZHAO Dongliang zhang Lijun wang Hongguang kang Shifeng College of Oceanic and Atmospheric Sciences Ocean University of ChinaQingdao 266100China National Key Laboratory of Electromagnetic Environment China Research Institute of Radiowave PropagationQingdao 266107China

Evaporation duct is an ubiquitous natural phenomenon over the ocean and can be diagnosed by evaporation duct *** model proposed by Paulus and Jeske and another model established by the American naval postgraduate school are the most widely *** are called PJ model and NPS model,*** methods are used to investigate the global sensitivity of PJ model and NPS model in China *** first method is based on meteorological and oceanographic observation data in China *** the system random error caused by sensor measurement inaccuracies,the mean relative error and mean absolute error are used as criterion for sensitivity *** second method,called Extended Fourier Amplitude Sensitivity Test(EFAST),takes into account the interaction between input parameters and is used for sensitivity *** results show that NPS model is more sensitive to the random errors of sensors than PJ *** mean relative errors of PJ model and NPS model are 11.43%and 14.81%,*** results of global sensitivity parameter analysis indicate that wind speed is the key factor of PJ model,while all input parameter of NPS model have relatively large total sensitivity *** addition,sensitivity analysis results confirm that wind speed is one of main driving factors for the formation of evaporation *** results are valuable for the selection of diagnosis models for evaporation duct,the evaluation of radio wave propagation in the marine atmospheric surface layer,and the prediction technique of evaporation duct based on numerical weather prediction(NWP)in China seas.

关键词： evaporation duct model EFAST method parameter sensitivity marine atmospheric boundary layer

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A k-Coverage Scheduling Scheme in Wireless Sensor Network Based on Hard-Core Process in Rayleigh Fading Channel

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China Communications 2015年第11期12卷 92-103页

作者： kang Lin LI Xiuhua zhang Yinghai wang Weidong LI Jinlan Beijing University of Posts and Telecommunications Taiyuan University of Science and Technology

Sensing coverage is a fundamental design issue in wireless sensor networks(WSNs),while sensor scheduling ensures coverage degree to the monitored event and extends the network *** this paper,we address k-coverage scheduling problem in dense WSNs,we maintain a connected k-coverage energy efficiently through a novel Hard-Core based Coordinated Scheduling(HCCS),in which hardcore is a thinning process in stochastic geometry that inhibits more than one active sensor covering any area redundantly in a minimum distance. As compared with existing coordinated scheduling,HCCS allows coordination between sensors with little communication ***,due to the traditional sensing models in k-coverage analysis is unsuitable to describe the characteristic of transmit channel in dense WSNs,we propose a novel sensing model integrating Rayleigh Fading and Distribution of Active sensors(RFDA),and derive the coverage measure and k-coverage probability for the monitored event under RFDA. In addition,we analyze the influence factors,i.e. the transmit condition and monitoring degree to the k-coverage probability. Finally,through Monte Carlo simulations,it is shown that the k-coverage probability of HCCS outperforms that of its random scheduling counterpart.

关键词： sleep scheduling rayleigh fading channel poisson point process hard-core process

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Dynamic Response of Floating Body Subjected to Underwater Explosion Bubble and Generated Waves with 2D Numerical Model

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Computer Modeling in Engineering & Sciences 2019年第2期118卷 397-423页

作者： Zhaoli Tian Yunlong Liu Shiping wang A Man zhang Youwei kang College of Shipbuilding Engineering Harbin Engineering UniversityHarbinHeilongjiangChina Division of Applied Mathematics Brown UniversityProvidence RI 02912USA CIMC Offshore Co.Ltd. YantaiShandongChina.

The low frequency load of an underwater explosion bubble and the generated waves can cause significant rigid motion of a ship that threaten its *** order to study the fluid-structure interaction qualitatively,a two-dimensional underwater explosion bubble dynamics model,based on the potential flow theory,is established with a double-vortex model for the doubly connected bubble dynamics simulation,and the bubble shows similar dynamics to that in 3-dimensional domain.A fully nonlinear fluid-structure interaction model is established considering the rigid motion of the floating body using the mode-decomposition *** test of the model is implemented by simulating the free rolling motion of a floating body in still *** the simulation of the interaction of the underwater explosion bubble,the generated waves and the floating body based on the presented model,the influences of the buoyancy parameter and the distance parameter are *** is found that the impact loads on floating body caused by underwater explosion bubble near the free surface can be divided into 3 components:bubble pulsation,jet impact,and slamming load of the generated waves,and the intensity of each component changes nonlinearly with the buoyance *** bubble pulsation load decays with the increase in the horizontal ***,the impact load from the generated waves is not monotonous to *** increases with the distance within a particular distance threshold,but decays thereafter.

关键词： Underwater explosion bubble dynamics fluid-structure interaction double-vortex model waves generated by underwater explosion.

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Transfer Matrix and Yangian Related to Chaplygin-Goryachev Top

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Chinese Physics Letters 1996年第9期13卷 641-643页

作者： XUE kang wang Zhou-fei GE Mo-lin zhang Hong-biao Institute of Theoretical Physics Northeast Normal UniversityChangchun 130024 Theoretical Physics Division Nankai Institute of MathematicsTianjin 300071

A new representation of Yangian for sl(2)is obtained from e(3)*** the given rational solution of the quantum Yang-Baxter equation the algebraic relations of the transfer matrix is discussed and a new transfer matrix r... 详细信息

关键词： algebra Yangian algebraic

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Flexo-photocatalysis in centrosymmetric semiconductors

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Nano Research 2024年第3期17卷 1173-1181页

作者： kang Liu Tong Wu Luying Xu Zhuangzhuang zhang Zhiyu Liu Longfei wang Zhong Lin wang Center on Nanoenergy Research School of Physical Science&TechnologyGuangxi UniversityNanning 530004China Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of SciencesBeijing 101400China College of Nanoscience and Technology University of Chinese Academy of SciencesBeijing 100049China Georgia Institute of Technology AtlantaGA 30332-0245USA Yonsei Frontier Lab Yonsei UniversitySeoul 03722Republic of Korea

The separation of photogenerated electron–hole pairs is vitally important for photocatalysis,which can be effectively promoted by polarization ***,it only manifests in piezoelectric/pyroelectric/ferroelectric materials that have a non-centrosymmetric ***,we demonstrate that the polarization enhanced photocatalysis(with wide spectra from ultraviolet(UV)light to visible light)can be achieved in centrosymmetric semiconductors,such asδ-MnO_(2) and TiO_(2) nanosheets integrated nanoflowers,by using the strain-gradient-induced flexoelectric polarization that is always overlooked in polarization-enhanced *** ultrasonic and illumination excitation,the organic pollutants(methylene blue(MB),etc.)can be effectively degraded within 30 min with excellent stability and *** with photocatalysis,the flexo-photocatalytic performance of above centrosymmetric semiconductors is substantially increased by 85%.Moreover,the factors related to flexo-photocatalysis such as material morphology,mechanical stimuli source,and adsorption are explored to deeply understand the mechanism of *** work opens up a way for high-performance photocatalysis in centrosymmetric semiconductors.

关键词： piezo-photocatalysis photocatalysis flexoelectricity polarization centrosymmetric semiconductor

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Improvement of wheat drought tolerance through editing of TaATX4 by CRISPR/Cas9

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Journal of Genetics and Genomics 2023年第11期50卷 913-916页

作者： Zhongxue wang Yifang zhang Zhensheng kang Hude Mao State Key Laboratory of Crop Stress Biology for Arid Areas and College of Plant Protection Northwest A&F UniversityYanglingShaanxi 712100China Yangling Seed Industry Innovation Center YanglingShaanxi 712100China State Key Laboratory of Crop Stress Biology for Arid Areas and College of Agronomy Northwest A&F UniversityYanglingShaanxi 712100China

Wheat(Triticum aestivum L.)is a staple cereal crop grown in arid and semi-arid areas worldwide and provides a major source of nutrition ***,its production is often affected by drought or water deficit,a problem which is expected to worsen because of climate change and a rapidly expanding global population;for example,the demand for agricultural water supplies is projected to increase by an estimated 17%by 2025 to compensate for global population growth(Lesk et al.,2016;Hickey et al.,2019.

关键词： CRISPR/Cas9 Wheat drought

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