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Dynamics of momentum distribution and structure factor in a weakly interacting Bose gas with a periodical modulation

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communications in Theoretical Physics 2020年第12期72卷 171-175页

作者： Ning Liu Z c Tu Department of Physics Beijing Normal UniversityBeijing 100875China

The momentum distribution and dynamical structure factor in a weakly interacting Bose gas with a time-dependent periodic modulation in terms of the Bogoliubov treatment are *** evolution equation related to the Bogoliubov weights happens to be a solvable Mathieu equation when the coupling strength is periodically *** exact relation between the time derivatives of momentum distribution and dynamical structure factor is derived,which indicates that the single-particle property is strongly related to the two-body property in the evolutions of Bose–Einstein *** is found that the momentum distribution and dynamical structure factor cannot display periodical *** stable dynamics,some particular peaks in the curves of momentum distribution and dynamical structure factor appear synchronously,which is consistent with the derivative relation.

关键词： Bose gas periodical coupling constant dynamical structure factor Mathieu equation

Sequential extraction of heavy metals during composting of urban waste

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chinese Journal of Geochemistry 2008年第2期27卷 121-125页

作者： Ayari F. chairi r. Kossai r. Laboratoire Eau et Environnement Institut National de recherche Scientifique et Technique B.P. 95-2050 Hammam-lifTUNISIE Laboratoire ressources minérales et Environnement. Faculté des Sciences de Tunis. 2092 Univ. Tunis El Manar Université de Tunis-IPEIT. Laboratoire de chimie de la Matière condensée 2 rue Jawaher Lel Nehru1008Monfleury-Tunis-Tunisie

In urban waste (the first matter of compost), elements such as copper, nickel and lead may be found in metallic state (wire, pile, accumulator, etc.), which is considered as non-dependent state. The work undertaken at the laboratory of composting of the INrST in Henchir Lihoudia (Tunis) showed that the produced compost does not contain any mobile metallic element and the portion related to organic fraction (bioavailable) is tiny in size. We supposed that many reactions involving decomposition and complexation from elements related to the matrix components occurred during composting. The existence and importance of this phenomenon can be evaluated by studying the evolution of metal contents in the different fractions extracted sequentially during composting process.

关键词：肥料重金属城市垃圾处理方法

γδ T cells,Tregs and epithelial cells interact with IL-33 in the lung

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cellular & Molecular Immunology 2021年第4期18卷 790-791页

作者： Julie Darrigues Julie c.ribot Institute de Medicina Molecular Joao Lobo Antunes Faculdade de MedicinaUniversidade de LisboaLisbonPortugal

Mucosal barriers are composed of an organized network of tightly joined cells that act as a critical first line of defense against *** their tissue hom ing properties and ability to sense environmental signals,gamma d... 详细信息

关键词： lung delta network

rIG-I-like receptor-induced IrF3 mediated pathway of apoptosis （rIPA）： a new antiviral pathway

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Protein & cell 2017年第3期8卷 165-168页

作者： Saurabh chattopadhyay Ganes c. Sen Department of Medical Microbiology and Immunology University of Toledo College of Medicine and Life Sciences 3000 Arlington Avenue Mailstop 1021 Toledo OH 43614 USA cleveland clinic Department of Immunology 9500 Euclid Avenue NE20 Cleveland OH 44195 USA

The innate immune response is the first line of host defense to eliminate viral infection. Pattern recognition receptors in the cytosol, such as rIG-I-like receptors （rLr） and Nod-like receptors （NLr）, and membrane bound Toll like receptors （TLr） detect viral infection and initiate transcription of a cohort of antiviral genes, including interferon （IFN） and interferon stimulated genes （ISGs）, which ultimately block viral replication. Another mechanism to reduce viral spread is through rIPA, the rLr-induced IrF3-mediated pathway of apoptosis, which causes infected cells to undergo pre- mature death. The transcription factor IrF3 can mediate cellular antiviral responses by both inducing antiviral genes and triggering apoptosis through the activation of rIPA. The mechanism of IrF3 activation in rIPA is dis- tinct from that of transcriptional activation; it requires linear polyubiquitination of specific lysine residues of IrF3. Using rIPA-active, but transcriptionally inactive, IrF3 mutants, it was shown that rIPA can prevent viral replication and pathogenesis in mice.

关键词： rIPA IrF3 innate immunity

computational Study on Furnace Process in a Multi-burner Boiler of Pulverized coal Fired Tangentially at Four corners

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Journal of central South University 2000年第3期12卷 152-155页

作者： Zhou, P Mei, c cong, Gc cent S Univ Technol Dept Appl Phys & Heat Engn Changsha 410083 Peoples R China

Aiming at the optimization of the operation condition, a general numerical method for calculating pulverized coal combustion in a full scale furnace fired tangentially at four corners is adopted. “ k ε ” turbulence model is used for the gas phases and a stochastic approach based on the Lagrangian technique is used for particle phases. Two competing reactions model for the coal devolatilization and PDF (the probability density function) method for the combustion of the gas phases are employed. In the numerical simulations, assuming the air distribution of second port level is of pagoda, waist drum and uniform type. The results show that pagoda type air distribution is advantageous to ignition and smooth combustion of pulverized coal, and suitable to inferior coal combustion in practice. In the present furnace, the igniting distance at 1st and 3rd corner is longer than that at 2nd and 4th corner. The results from numerical calculations are in good agreement with those of observed in practice.

关键词： power station boiler combustion of pulverized coal numerical simulation

Nutritional stress reduces flight performance and exploratory behavior in a butterfly

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Insect Science 2019年第5期26卷 897-910页

作者： Elisabeth reim Danny Eichhorn Jan D.roy Philip o.M.Steinhoff Klaus Fischer Zoological Institute and Museum Greifswald UniversityGreifswaldGermany

Anthropogenic global change, including agricultural intensification and climate change, poses a substantial challenge to many herbivores due to a reduced availability of feeding resources. The concomitant food stress is expected to detrimentally affect performance, amongst others in dispersal-related traits. Thus, while dispersal is of utmost importance to escape from deteriorating habitat conditions, such conditions may negatively feedback on the ability to do so. Therefore, we here investigate the impact of larval and adult food stress on traits related to dispersal ability, including morphology, physiology, flight performance, and exploratory behavior, in a butterfly. We show that inadequate nutrition during development and in the adult stage dim inishes flight performance, despite som e reallocation of somatic resources. Detrimental effects of food stress on flight performance were mainly caused by reductions in body mass and storage reserves. Similar results were found for exploratory behavior. Furthermore, exploratory behavior was found to be (moderately) repeatable at the individual level, which might indicate the existence of a personality trait. This notion is further supported by the fact that flight performance and exploratory behavior were positively correlated, potentially suggesting the existence of a dispersal syndrome. In summary, our findings may have important implications for dispersal in natural environments, as the conditions requiring dispersal the m ost impair flight ability and thereby likely dispersal rates.

关键词： condition dispersal syndrome flight ability food stress habitat degradation resource allocation

characterization of Fe_3o_4/P(St-MPEo) Amphiphilic Magnetic Polymer Microspheres

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chemical research in chinese Universities 2002年第4期18卷 458-461页

作者： cHAN ALBErT S. c. YIP c. W. open Laboratory of chirotechnology and Department of Applied Biology and chemical Technology Open Laboratory of Chirotechnology and Department of Applied Biology and Chemical Technology Hong Kong Polytechnic University Hong Kong P. R. ChinaHong Kong Polytechnic University Hong Kong P. R. China

Amphiphilic magnetic microspheres consisting of styrene and poly(ethylene oxide) macromonomer(MPEo) were prepared by dispersion copolymerization in the presence of Fe_3o_4 magnetic fluid in an ethanol/water medium. The sizes of the magnetic microspheres and their distribution were characterized by means of scanning electron microscopy(SEM). The surface morphology and the average surface roughness of the microspheres were investigated by virtue of atomic force microscopy(AFM). It was found that the microspheres exhibit microscopic phase-separate and the mean square surface roughness of the microspheres increases with increasing MPEo used in the copolymerization. The amphiphilic magnetic microspheres containing 0 4-3 5 mg/g hydroxyl groups could be prepared from MPEo with different concentrations and styrene.

关键词： Amphiphilic magnetic polymer Microsphere copolymerization

Detecting trends in body size: empirical and statistical requirements for intraspecific analyses

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current Zoology 2019年第5期65卷 493-497页

作者： c.M.GIENGEr Ned A.DocHTErMANN c.richard TrAcY Department of Biology Center of Excellence for Field BiologyAustin Peay State UniversityClarksvilleTNUSA Department of Biological Sciences North Dakota State UniversityFargoNDUSA Department of Biology Program in EcologyEvolutionand Conservation BiologyUniversity of NevadaRenoNVUSA

Attributing biological explanations to observed ecogeographical and ecological patterns require eliminating potential statistical and sampling artifacts as alternative explanations of the observed ***,we assess the role of sample size,statistical power,and geographic inclusivity on the general validity and statistical significance of relationships between body size and latitude for 3 well-studied species of *** extend those analyses to emphasize the importance of using statistically robust data in determining macroecological *** examined intraspecific trends in body size with latitude in chelydra serpentina,chrysemys picta,and Trachemys scripts using Pearson's correlations,diagnostic tests for influential points,and *** data were insufficient to ascertain a latitudinal trend in body size for *** or *** was a significant relationship for ***,however,resampling analyses show that,on average,16 of the 23 available independent populations were needed to demonstrate a significant relationship and that at least 20 of 23 populations were required to obtain a statistically powerful correlation between body size and ***,restricting the latitudes of populations resampled shows that body size trends of *** were largely due to leveraging effects of populations at the edge of the species *** results suggest that broad inferences regarding ecological trends in body size should be made with caution until underlying(intraspecific)patterns in body size can be statistically and conclusively demonstrated.

关键词： Bergmann's rule geographic variation macroecology resampling sensitivity analysis statistical power turtle

Adaptive pass planning and optimization for robotic welding of complex joints

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Advances in Manufacturing 2017年第2期5卷 93-104页

作者： H. c. Fang S. K. ong A. Y. c. Nee Department of Mechanical Engineering Faculty ofEngineering National University of SingaporeSingapore 117575 Singapore

current industrial robotic welding systems can- not achieve automated solutions for multi-layer multi-pass welding of complex joints due to the presence of non- uniform and irregular welding groove geometries. This paper presents an adaptive pass planning approach for robotic welding of such complex joints. The welding groove is first segmented considering both the variation in groove dimension and the reachability of the robot welding torch. For each welding segment, the welding passes are planned to be in accordance with welding practices, viz., keeping the same number of welding passes in each layer while maintaining consistent welding parameters. An adaptive pass adjustment scheme is developed to address the discrepancies between the simulated results and the actual welding deposition after finishing a few layers of welding. corresponding robot paths are generated and optimized to ensure minimum joint movement subject to three constraints, viz., reachability, collision-free and singularity avoidance. The proposed approach has been sim- ulated with the arc welding of a Y-type joint found typically in offshore structures.

关键词： robotic welding Multi-pass planning - Pass adjustment robot path planning