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Idealization Second Quantization of Composite Particles

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Communications in Theoretical Physics 2001年第11期36卷 525-530页

作者： ZHOU Duan-lu yu Si-Xia SUN Chang-Pu Institute of Theoretical Physics Academia SinicaBeijing 100080China Institute of Theoretical PhysicsAcademia SinicaBeijing 100080China Institute of Theoretical PhysicsAcademia SinicaBeijing 100080China

A practical method is developed to deal with the second quantization of the many-body system containing the composite *** our treatment,the modes associated with composite particles are regarded approximately as independent ones compared with those of unbound *** field operators of the composite particles thus arise naturally in the second quantization *** be emphasized,the second quantization Hamiltonian has the regular structures which correspond clearly to different physical processes.

关键词： second quantization,composite particles

Doubly Periodic Propagating Wave Patterns of （2＋1）-Dimensional Maccari System

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Communications in Theoretical Physics 2007年第3期47卷 397-402页

作者： HUANG Wen-Hua LIU yu-lu MA Zheng-Yi College of Science Zhejiang Huzhou University Huzhou 313000 China Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China College of Science Zhejiang Lishui University Lishui 323000 China

Using the variable separation approach, we obtain a general exact solution with arbitrary variable separation functions for the （2＋ 1）-dimensional Maccari system. By introducing Jacobi elliptic functions dn and nd in the seed solution, two types of doubly periodic propagating wave patterns are derived. We invest/gate the wave patterns evolution along with the modulus k increasing, many important and interesting properties are revealed.

关键词： Maccari system variable separation method Jacobi elliptic function periodic wave

Effect of Hot Pressing on Microstructure and Mechanical Properties of Bulk Nanocrystalline Fe_3Al Materials Containing Manganese Element

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Journal of Iron and Steel Research International 2011年第3期18卷 65-71页

作者： LI yu-feng LA Pei-qing WEI yu-peng lu Yang YANG Yang State Key Laboratory of Gansu Advanced Nonferrous Materials Lanzhou University of TechnologyLanzhou 730050GansuChina

Bulk nanocrystalline Fe3Al materials containing manganese of 10% were prepared by aluminothermic *** pressing of those materials was performed at different temperatures and *** microstructures of the alloy were investigated by optical microscope（OM） and electron probe microanalyzer（EPMA）.The grain sizes of the materials were analyzed by X-ray diffraction（XRD） and transmission electron microscope（TEM）.The results showed that the grain sizes of the materials increase after hot *** grain sizes of the materials decrease with increasing the hot pressing times at the same temperature and the grain sizes of the materials increase with increasing hot pressing temperatures at identical *** hardness and compressibility of the materials were also *** results showed that the hardness decreases with increasing hot pressing times at 800 ℃ and hardness increases with increasing the hot pressing *** variation of hardness with grain size of the nanocrystalline Fe3Al materials after hot pressing is contrary to the Hall-Petch *** materials are not broken during hot pressing and exhibit good plasticity and compressibility.

关键词： hot pressing Fe3Al nanostructure material microstructure mechanical property

Numerical modeling of bed deposition in rapid flow-like landslides:a case study of the Gaolou landslide in Shaanxi Province,China

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Journal of Mountain Science 2021年第3期18卷 599-613页

作者： SHEN Wei LI Tong-lu BERTI Matteo LI Ping LEI yu-lu SHEN yue-qiang Department of Biological Geological and Environmental SciencesUniversity of BolognaBologna 40126Italy Department of Geological Engineering Chang'an UniversityXi'an 710064China

Some flow-like landslides tend to lose materials while moving on a relatively dry sliding *** phenomenon is called bed *** contrast to the bed entrainment phenomenon,bed deposition is relatively poorly ***,an improved depth-averaged model is proposed to quantify this *** deposition depth is calculated according to the momentum conservation of the deposited mass,and the rheological property of the sliding mass on the bottom is modified considering an abrupt increase in the depth of the sliding surface after *** the proposed model,the Gaolou landslide,a typical flowlike landside occurring on October 6 th,2006 with an obvious bed deposition phenomenon in Shaanxi Province of China,is simulated to investigate the influence of bed deposition on its propagation *** results indicate that the proposed model can effectively depict the bed deposition phenomenon in the Gaolou *** deposition dissipates part of the kinetic energy of this landslide;thus,the simulated debris inundation area would likely be overestimated when this effect is *** the other hand,the thin liquefied layer formed by the bed deposition process reduces the friction energy dissipation,contributing to the high mobility of this landslide.

关键词： Natural hazards Flow like landslides Numerical simulation Depth-averaged model Bed deposition

Doubly Periodic Propagating Wave for (2+1)-Dimensional Breaking Soliton Equation

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Communications in Theoretical Physics 2008年第2期49卷 268-274页

作者： HUANG Wen-Hua LIU yu-lu ZHANG Jie-Fang College of Science Huzhou University Huzhou 313000 China Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China Institute of Nonlinear Physics Zhejiang Normal University Jinhua 321000 China

Using the variable separation approach, we obtain a general exact solution with arbitrary variable separation functions for the （2＋1）-dimensional breaking soliton system. By introducing Jacobi elliptic functions in the seed solution, two families of doubly periodic propagating wave patterns are derived. We investigate these periodic wave solutions with different modulus m selections, many important and interesting properties are revealed. The interaction of Jabcobi elliptic function waves are graphically considered and found to be nonelastic.

关键词： breaking soliton equation variable separation method Jabobi elliptic function periodic wave

Sustainable curcumin-based smart tough fluorescent hydrogels for anti-counterfeiting applications

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Green Chemical Engineering 2023年第4期4卷 379-386页

作者： Xiubin Xu Chuanghong Xiao Yanting Chen Danfeng yu yu lu Ian Wyman Xu Wu School of Chemistry and Chemical Engineering Guangzhou UniversityGuangzhou510006China Department of Chemistry Queen's UniversityKingstonOntarioK7L 3N6Canada

There is currently great interest in developing an environment-friendly,low-cost,and scalable approach for producing stimuli-responsive fluorescent hydrogels(FHs)with excellent mechanical property,rewritable fluorescence,and dual anti-counterfeiting ***,by applying natural,environment-friendly,and sustainable curcumin as a responsive agent,tough pH-responsive FHs(pH-FHs)are fabricated via a facile preparation *** materials have outstanding mechanical performances:ultimate stress of 180 kPa,an ultimate strain of~2500%,and good anti-fatigue performances against *** pH-FHs are able to sense ammonia and formaldehyde gas,resulting in both a color change and fluorescence for dual anti-counterfeiting *** sensing information is stored individually by the pH-FHs and could be externally removed using formaldehyde gas to achieve a rewritable *** study provides valuable insights that are expected to facilitate the development of smart FHs for information encryption and anti-counterfeiting applications.

关键词： Curcumin Fluorescence hydrogels Anti-counterfeiting Information storage Rewritable fluorescence

Dynamic Performance Analysis of the Tuned Heave Plate System for Semi-Submersible Platform

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China Ocean Engineering 2018年第4期32卷 422-430页

作者： LIANG Hai-zhi LIU Kun LI lu-yu OU Jin-ping School of Civil Engineering Qingdao University of Technology State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology School of Civil and Transportation Engineering South China University of Technology

Logistical supply is costly for the deepwater oil and gas exploitation, thereby it is necessary to develop a novel power supply solution to improve the offshore structure’s self-holding capacity. The two-body point absorbers, as a renewable energy device, have achieved a rapid development. Heave plate is used to constrain the truss’ s motion in the two-body point absorber, and the floater moves along the truss up and down. This two-body point absorber can be considered to be an essentially mass-spring-damper system. And it is well known that the heave plates have been widely used in the Spar platform to suppress the heave motions. So if the two-body point absorber can be modified to combine with offshore floating structures, this system can not only offer electric power to support operations or daily lives for the platform, but also control the large motions in the vertical plane. Following this concept, a novel tuned heave plate(THP) system is proposed for the conventional semi-submersible platform. In order to investigate the dynamic performances of the single THP, two experiments are conducted in this paper. First, the hydrodynamic coefficients of the heave plates are studied, and then the THP experiments are carried out to analyze its dynamic performance. It can be concluded that this THP is feasible and achieves the design objective.

关键词： tuned heave plate hydrodynamics wave energy conversion dynamic performance

PTCs promoted biphasic oxidation of ethylbenzene catalyzed by NHPI and CoSPc

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Chinese Chemical Letters 2012年第8期23卷 895-898页

作者： yu lu Zhou Sha Sha Lin Dao Hong Xia yu Zhi Xiang College of Science State Key Laboratory of Heavy OilChina University of PetroleumQingdao 266580China

An easy workup and environmentally friendly method to convert ethylbenzene into the corresponding oxides, catalyzed by a combined catalytic system consisting of NHPI and CoSPc, was developed in a water involved liquid-liquid heterogeneous system. Experimental results showed that the reaction performed well facilitated by PTCs at multigrams material level, under which the conversion rate of ethylbenzene and the selectivity of acetophenone reached 60.6% and 95.2% after 0.5 h of reaction in oxygen atmosphere. An oxidation process was orooosed at the end of this oaoer.

关键词： Ethylbenzene Aerobic oxidation NHPI CoSPc PTC

A late Carboniferous transition from subduction to collision:Tectonosedimentary evidence from southern Junggar,NW China

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Geoscience Frontiers 2024年第3期15卷 166-179页

作者： Shuoqin Hou Di Li Dengfa He yu lu yu Zhen Hao Yang Dan Fan Key Laboratory of Marine Reservoir Evolution and Hydrocarbon Accumulation Mechanism the Ministry of Educationand School of Energy ResourcesChina University of Geosciences(Beijing)Beijing 100083China

The Carboniferous to Permian tectono-sedimentary evolution of the southern Junggar area brings new insights into understanding the subduction-collision processes in the northern Tianshan *** geophysics,geochemistry,and geochronology approaches,this study investigates the Carboniferous-Permian strata in the southern Junggar *** results have revealed three distinct tectono-stratigraphic evolutionary stages,each marked by a distinctive volcano-sedimentary *** Early Carboniferous strata suggest intense volcanic activities in the southern Junggar *** the Late Carboniferous,the southern Junggar Basin was controlled by normal faulting in an extensional setting,receiving sedimentary inputs from the Junggar *** Lower Permian,unconformably overlying the Upper Carboniferous,was shaped by an extensional regime and is comprised by volcano-clastic sequences that received detritus from the Yili-Central Tianshan *** findings indicate that a Late Carboniferous forearc basin developed in the southern Junggar area,and it evolved into a post-collisional rift in the Early *** period marked a dynamic shift from bidirectional subduction(rollback)to the detachment of the North Tianshan oceanic *** propose that the collision between the YiliCentral Tianshan block and the Junggar terrane,along with the closure of the North Tianshan Ocean,likely occurred in the Late Carboniferous(ca.306-303 Ma).

关键词： Tectono-sedimentary evolution Tectonic transition Carboniferous-Permian Junggar Basin North Tianshan Ocean