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Spinescent patterns in the flora of Jiaozi Snow Mountain,Southwestern China

Plant Diversity 2020年第2期42卷 83-91页

作者： Qi Xu Simcha lev-Yadun Lu Sun Zhe Chen Bo Song Hang Sun Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of Sciences132 Lanhei RoadKunming.650201YunnanChina University of Chinese Academy of Sciences Beijing100049China Department of Biology&Environment Faculty of Natural SciencesUniversity of Haifa-OranimTivon36006Israel

Spinescence has been thought to have evolved mainly as a defense against ***,studying its evolution in a whole flora is an excellent approach for understanding long-term plant-herbivore *** this study,we characterized the spinescent plant species of Jiaozi Snow Mountain,Southwestern China,in order to explore the effects of life forms,plant organs,phylogenetic position,and phytogeographical origin on spinescence *** Jiaozi Snow Mountain flora includes 137 spinescent species(9.2%)out of 1488 angiosperm *** found that in these spinescent species,vegetative organs(70.0%)were significantly more defended than reproductive organs(43.8%).Life form had a significant effect on spinescence *** species(18.6%)were more likely to be spiny than non-woody species(6.4%);moreover,woody species mostly defend their vegetative organs(92.2%),whereas herbaceous species mostly defend their reproductive organs(73.3%).For woody plants,leaf habit has a significant effect on ***,spinescence was more common on the reproductive organs of deciduous woody species than on those of evergreen woody species;furthermo re,spinescence was more common on the leaf blades of evergreens than on those of deciduous species;however,the proportion of spinescent petioles in deciduous species was significantly higher than in *** most common spine color was yellow(40.8%),followed by white(16.8%),red(15.8%),and brown(14.3%);furthermore,74.4%of spinescence that showed aposematic color was a different color than the plant organ on which *** findings suggest that spinescence is visually aposematic in the Jiaozi Snow Mountain ***,more families tended to have spines on vegetative organs(83.3%in vegetative organs,50.0%in reproductive organs),but the phylogenetic signals were *** proportion of spinescence was not significantly different between tropical(9.8%of genera,7.6%of species)and temperate(13.2%of ge

关键词： Herbivory Life form Physical defense Trade-off Plant apparency Spinescence

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Applications of two electric arc plasma torches for the beneficiation of natural quartz

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International Journal of Minerals,Metallurgy and Materials 2019年第3期26卷 267-273页

作者： Yuri-Mikhailovich Grishin Long Miao lev-Alekseevich Borisov Nikolay-Mikhailovich Serykh Alexey-Yurievich Kulagin Department of Thermal physics Bauman Moscow State Technical University Federal State Unitary Enterprise Tsentrkvarts

Experimental beneficiation processes of quartz concentrate in arc plasma torches of two different types and electric powers were studied. An emission scanning electron microscope and a universal laser analyzer were used to investigate the structures as well as the size distributions of grains and microparticles. Inductively coupled plasma–mass spectrometry was used to determine the chemical compositions of nonstructural solid-phase mineral impurities in quartz concentrate. Results related to the modified grains' structure and size distribution, the compositions of impurities, and the gas–liquid inclusions in the quartz concentrate were investigated. The total impurities concentrations in the processed grains were found to satisfy the IOTA-STD standard(industry standard for grading high quality fused quartz products). The optimal condition(i.e., the optimal specific plasma enthalpy) for the production of high-purity quartz in arc plasma torches was found to depend on the geological-genetic type and the structural and textural features(i.e., chemical composition and gas–liquid inclusions) of the quartz concentrate.

关键词： low-temperature plasma beneficiation high purity quartz arc plasma torch IOTA-STD standard

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Onsite strength determination for early-opening decision making of high early strength concrete pavement

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Journal of Traffic and Transportation Engineering(English Edition) 2023年第2期10卷 291-303页

作者： Katelyn Kosar Lucio Salles de Salles Naser Pourakbar Sharifi Julie Vandenbossche lev Khazanovich Department of Civil and Environmental Engineering University of PittsburghPittsburghPA 15261USA Department of Civil Engineering Technology Environmental Management and SafetyRochester Institute of TechnologyRochesterNY 14623USA

High early strength(HES)concrete pavements are commonly opened to traffic within the first 24 h after construction,making early-opening decisions critical for pavement quality and traffic ***,most state departments of transportation rely on compressive strength testing for early-opening decision ***,there laboratory tests are labor intensive,costly and not always representative of field strength *** this study,non-destructive testing(maturity and ultrasonic tomography)was explored for faster and reliable in-situ strength *** experimental section constructed using HES concrete was routinely monitored using compressive testing,maturity,and ultrasonic tomography in the first 24 h after *** shear wave velocity,measured using ultrasonic tomography,was able to capture the strength-gain variability within a single slab and between different slabs due to the ability to monitor several locations in a short period of *** results were consistently conservative in the first 24 h of *** show that both maturity testing and ultrasonic tomography are able to replace or add to conventional strength testing for HES concrete pavements to facilitate making the opening decision within the first 24 *** tomography proved more beneficial as a result of the device's portability,increased speed of testing,and accurate estimations of HES concrete strength for the entire pavement length.

关键词： Road engineering High early strength concrete pavement Traffic early-opening Strength Maturity Ultrasonic tomography

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Impact damage testing based on high-speed continuous water jet aircraft coatings

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Chinese Journal of Aeronautics 2024年第10期37卷 249-264页

作者： Minggong SHA Ying SUN Yutong LI Yiming LIU Gregory FEDOTENKOV lev RABINSKIY Arseniy BABAYTSEV Yulong LI School of Civil Aviation Northwestern Polytechnical UniversityXi’an 710072China Joint International Research Laboratory of Impact Dynamics and Engineering Application Xi’an 710072China Shaanxi Impact Dynamics and Engineering Application Laboratory Xi’an 710072China NPU Yangzi River Delta Research Institute Suzhou 215400China Moscow Aviation Institute(National Research University) Moscow 125993Russia

When an aircraft passes through a rainy area at high speed,the coating on the front edge of the fuselage will be continuously eroded by raindrops,causing the coating to wear,crack or even peel *** paper uses carbon fiber T300 material as the base material,and at the different impact speeds and impact numbers,water cutting equipment was used to simulate the erosion of the coating caused by the continuous impact of water *** damage morphology of samples at different damage stages was observed by digital microscope and Scanning Electron Microscope(SEM),and the damage evolution curve was established to analyze and reveal the damage behavior and damage mechanism of rain *** results show that the degree of damage experienced an increasing trend with the increase of impact numbers and speed,until circular peel damage was formed;no damage occurred during the incubation period,and the curvature of the damage evolution curve increased significantly after the expansion period and eventually showed a stable expansion *** mechanical properties of the coating material were the main influencing factors of its rain corrosion ***,the axially symmetric unsteady contact problem of droplets impacting the surface of a solid deformable body was *** the contact area was determined based on the iterative algorithm boundary positioning method.A mathematical model and closed mathematical formula describing the unsteady interaction between a droplet and a solid deformable obstacle were proposed.

关键词： Rain erosion damage Liquid-solid impact Multiple jets Composite materials Impact dynamics

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Flexible pavement longitudinal joint quality evaluation using non-destructive testing

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Journal of Road Engineering 2024年第2期4卷 189-202页

作者： Hamad Bin Muslim Syed Waqar Haider lev Khazanovich Department of Civil and Environmental Engineering Michigan State UniversityEast LansingMI 48824USA Department of Civil and Environmental Engineering University of PittsburghPittsburghPA 15261USA

Longitudinal joint construction quality is critical to the life of flexible *** deteriorated longitudinal joints has become a challenge for many highway *** the joint's quality through better compaction during construction can help achieve flexible pavements with longer service lives and less *** quality control(QC)and quality assurance(QA)plans provide limited ***,the risk of missing areas with poor joint compaction is significant.A density profiling system(DPS)is a non-destructive alternative to conventional destructive evaluation *** can provide quick and continuous real-time coverage of the compaction during construction in *** paper presents several case studies comparing various types of longitudinal joints and demonstrating the use of DPS to evaluate the joint's compaction *** paper shows that dielectric measurements can provide valuable insight into the ability of various construction techniques to achieve adequate levels of compaction at the longitudinal *** paper proposes a dielectric-based longitudinal joint quality index(LJQI)to evaluate the relative compaction of the joint during *** also shows that adopting DPS for assessing the compaction of longitudinal joints can minimize the risk of agencies accepting poorly constructed joints,identify locations of poor quality during construction,and achieve better-performing flexible pavements.

关键词： Sustainable pavements Dielectric/density profiling system Quality assurance Non-destructive testing Asphalt longitudinal joint

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Clustering of Pathogen-Response Genes in the Genome of Arabidopsis thaliana

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Journal of Integrative Plant Biology 2011年第10期53卷 824-834页

作者： Olga A.Postnikova Natalia Y.Minakova Alexander M.Boutanaev lev G.Nemchinov United States Department of Agriculture Agricultural Research ServicePlant Sciences InstituteMolecular Plant Pathology Laboratory Institute of Basic Biological Problems Russian Academy of Sciences

Previously, we used heterologous expressed sequence tag （EST） mapping to generate a profile of 4 935 pathogen-response genes of Arabidopsis thaliana. In this work, we performed a computer analysis of this profile, revealing 1594 non-homologous clustered genes distributed among all A. thafiana chromosomes, whose co-regulation may be related to host responses to pathogens. To supplement computer data, we arbitrarily selected two clusters and analyzed their expression levels in A. thaliana ecotypes Col-0 and C24 during infection with the yellow strain of Cucumber mosaic virus CMV（Y）. Ecotype Col-0 is susceptible to CMV（Y）, whereas C24 contains the dominant resistance gene RCY1. Upon infection with CMV（Y）, all clustered genes were significantly activated in the resistant ecotype C24. In addition, we demonstrated that posttranslational histone modifications associated with trimethylation of histone H3 lysine 27 are most likely involved in regulation of several cluster genes described in this study. Overall, our experiments indicated that pathogen-response genes in the genome of A. thaliana may be clustered and co-regulated.

关键词： CMV H3K27me3 heterologous EST mapping clustering of defense-related genes.

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A new cryptand/paraquat [2]pseudorotaxane

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Science China Chemistry 2010年第4期53卷 858-862页

作者： ZAKHAROV lev N. SLEBODNICK Carla RHEINGOLD Arnold L. GIBSON Harry W. Department of Chemistry and Biochemistry University of California Department of Chemistry Virginia Polytechnic Institute and State University

A new cryptand/paraquat [2]pseudorotaxane and its crown ether analog were synthesized and characterized by proton NMR, mass spectrometry, and single crystal X-ray analysis. The Job plots based on proton NMR data demonstrated that both the complex between cryptand 1 and paraquat derivative 2a and the complex between bis(p-phenylene)-34-crown-10 (3) and paraquat derivative 2b have 1:1 stoichiometry in solution. The apparent association constants (Ka,exp) of 1·2a and 3·2b calculated for 1:1 complexes were 1.4 (±0.2) × 104 and 4.7 (± 0.5) × 102 M-1, respectively. X-ray analysis showed that 1·2a is stabilized by ten hydrogen bonds and face-to-face π-stacking interactions in the solid state, while 3·2b is stabilized by four hydrogen bonds and face-to-face π-stacking interactions. As well as in the X-ray structure of 1·2c, a water molecule acts as a hydrogen bridge between the β-pyridinium protons of 2a and the ether oxygen atoms of 1 in 1·2a. The successful preparation of 1·2a demonstrated that the tert-butyl group is not big enough to be a stopper for rotaxanes based on 1.

关键词： host-guest system self-assembly pseudorotaxane cryptand paraquat

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Geometric Interpretation of the Origin of the Universe

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Journal of Modern Physics 2022年第2期13卷 89-99页

作者： Bohdan lev Bogolyubov Institute for Theoretical Physics NAS of Ukraine Metrolohichna 14-b Kyiv Ukraine

An approach to the theory of geometrization of the Universe is proposed. The wave function of the Universe is represented by the Clifford number with the transfer rules that have the structure of the Dirac equation for any manifold. Solutions of this equation may be obtained in terms of the geometric interpretation. A new model is proposed that can explain the manifestation of the dark energy and dark matter in the Universe as a geometrical entity with a mechanism involving the spontaneous symmetry breaking.

关键词： Clifford Algebra Wave Function Geometric Interpretation Structural Equations

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Critical Equatorial Trajectories of Massless Particles in a Kerr Spacetime

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Journal of High Energy Physics, Gravitation and Cosmology 2022年第3期8卷 647-656页

作者： lev Morgovsky Johann Wolfgang Goethe-Universitä t Frankfurt am Main Frankfurt Germany

In the presented work a closed analytical expression is obtained that describes the critical photon orbits in the equatorial plane of a spinning Kerr black hole (BH). A significant difference in the behavior of photons with prograde and retrograde directions of rotation is shown. The photons with prograde rotation exhibit an exponential increase in the deflection angle together with the number of rotations around the BH as its spin parameter increases. The number of rotations exceeds 103 when spin parameter of the BH reaches 0.999. At the same time this value decreases insignificantly for reverse rotating photons and is less than that for the non-spinning Schwarzschild BH. The transition to a zero spin limit made it possible to determine the number of photon rotations along the critical trajectory for such BHs.

关键词： Black Holes Gravitation Light Deflection Photon Trajectories

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Phenomena at three-phase electroslag remelting

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China Foundry 2021年第6期18卷 557-564页

作者： Zhong-li Liu lev Medovar Ganna Stovpchenko Volodymyr Petrenko Artem Sybir Yev.Volchenkov Yantai University Yantai 264005ShandongChina E.O.Paton Electric Welding Institute Kyiv 03180Ukraine National metallurgical academy of Ukraine Dnipro 49600Ukraine

The electroslag remelting(ESR)process is widely used to produce high-quality ingots and billets for high-alloyed steels and *** the single-phase and three-phase alternating current diagram with bifilar and monofilar connection are in use for heavy ingot *** numerical simulation of the three-phase bifilar circuit for the 120 t three-phase bifilar six-electrode ESR furnace at different variants of electric connection was presented and *** the bifilar diagram of power supply,the geometrical location of electrodes in a mould holds critical importance for performances:the close location of bifilar pair electrodes provides the highest heat productivity,but the equidistant location of electrodes gives a much more uniform heat *** monofilar mulit-electrode diagram of three-phase connection without phase shift shows the most uniform distribution of potential and heat generation as well as a favorable magnetic field that makes this kind the most promising for providing a high quality of heavy ingots.

关键词： electroslag remelting three-phase circuit bifilar monofilar simulation heavy ingot

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