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Twin cogenesis

Communications in Theoretical Physics 2023年第4期75卷 34-49页

作者： Wan-Zhe Feng Jiang-hao yu Center for Joint Quantum Studies and Department of Physics School of ScienceTianjin UniversityTianjin 300350China Institute of Theoretical Physics Chinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China

We investigate a cogenesis mechanism within the twin Higgs setup that can naturally explain the nature of dark matter,the cosmic coincidence puzzle,little hierarchy problem,leptogenesis,and the tiny neutrino *** heavy Majorana neutrinos are introduced to the standard model sector and the twin sector respectively,which explain the tiny neutrino masses and generate the lepton asymmetry and the twin lepton asymmetry at the same *** twin cogenesis mechanism applies to any viable twin Higgs model without an explicit Z_(2)breaking in the leptonic sector and evading theΔN_(eff) *** illustrate the twin cogenesis mechanism using the neutrino-philic twin two Higgs doublet model,a newly proposed model to lift the twin neutrino masses with spontaneous Z_(2)*** dark photon with a Stueckelberg mass O(10)MeV ensures the energy in the twin sector as well as the symmetric component of twin sector particles can be *** lightest twin baryons are the dark matter candidates with masses of approximately 5.5 GeV,which explains naturally the amount of dark matter and visible matter in the Universe are of the same *** also demonstrate twin cogenesis in the fraternal twin Higgs setup,in which the dark matter candidate is the twin bottom bound stateΩ’_(b’b’b’).

关键词： cogenesis cosmic coincidence asymmetric dark matter leptogenesis neutrino mass

Visible-light-promoted and photocatalyst-free trifluoromethylation of enamides

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Science China Chemistry 2016年第2期59卷 195-198页

作者： hao Wang yuanzheng Cheng Shouyun yu State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry and Chemical Engineering Nanjing University Nanjing 210093 China

An efficient and practical method is developed for the trifluoromethylation of enamides using Umemoto's reagent as the trifluoromethylating reagent. These reactions proceeded under visible light irradiation without an... 详细信息

关键词： enamide photochemistry visible light trifluoromethylation radical

3D MHD simulation of the double-gradient instability of the magnetotail current sheet

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Science China(Technological Sciences) 2018年第9期61卷 1364-1371页

作者： DUAN AiYing ZHANG Huai LU hao yu Key Laboratory of Computational Geodynamics University of Chinese Academy of Sciences State Key Laboratory of Space Weather Chinese Academy of Sciences School of Space and Environment Beihang University

Flapping motion of the current sheet(CS) is an important physical process in the Earth's magnetotail. The magnetic doublegradient model, which includes both the instability and wave modes, offers a reasonable explanation for the exciting and propagation of the flapping wave. In this paper, we apply an advanced numerical magnetohydrodynamic(MHD) scheme(conservation element and solution element(CESE)-MHD) to simulate the magnetic double-gradient instability in an idealized current sheet that mimics the magnetotail configuration. We initialize the simulations with a numerically relaxed magnetotail equilibrium, in which the normal component of the magnetic field has a tailward gradient. It is confirmed in our simulation that the instability develops in the current layer. The growth rate of the instability yielded from the simulation is very close to the prediction of theory, with a relative deviation of only ten percent. The results demonstrate that the CESE-MHD scheme is very powerful in numerical study of the double-gradient mechanism of the CS flapping mode, and can be used for further investigations of the flapping motion in more realistic CS configurations.

关键词： Earth's magnetotail current sheet flapping magnetohydrodynamic numerical simulation

Surface pattern based on an azobenzene-containing copolymer thin film and its light-driven morphology modulation

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第7期14卷 504-513页

作者： Lei ZHANG Li WANG hao-jie yu State Key Laboratory of Chemical Engineering Department of Chemical and Biological Engineering Zhejiang University

A type of azobenzene-containing block copolymer polymethyl methacrylate-b-poly (n-butylmethacrylate-co-6-(4-(phenylazo) benzoate) hexyl methacrylate) (PMMA-b-(PnBMA-co-PAzoMA)) was synthesized by the atom transfer radical polymerization (ATRP). Macroinitiator polymethyl methacrylate (PMMA) was prepared by ATRP and used to initiate the copolymerization of monomer n-butyl methacrylate (nBMA) and azobenzene-based methacrylate monomer (AzoMA). Herein, three block copolymers with different molecular weights and block volume fractions were obtained and spin-coated on a silicon substrate or quartz plate before annealing at 180℃ for 14 h. The surface morphologies in these annealed copolymer films were observed by atomic force microscopy (AFM). Bicontinuous stripe or island patterns with different sizes were formed dependent on the film thickness. These ordered patterns are considered to be formed arising from the dewetting process of the surface layer in the copolymer film. Photoisomerization of azobenzene units in the copolymer films changed the dewetting behaviors of the surface layer of the thin film. Therefore, some copolymer annealed films showed a reversible morphology conversion between bicontinuous stripe and island structure when exposed to UV light and upon being stored in the dark. It was found that the composition of the block copolymer had obvious influences on the photoinduced morphology conversion behaviors in these copolymer thin films. When the volumes of PnBMA and PAzoMA phases in the block copolymer were large enough, the surface morphology could be modulated by UV light irradiation and storage in the dark. This work proposes a new possibility for photoinduced control and design of the dewetting processes of thin films using a linear block copolymer.

关键词： Dewetting behavior Photoinduced morphology modulation Atom transfer radical polymerization (ATRP) Block copolymer

Austenite grain growth behavior of Q1030 high strength welded steel

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International Journal of Minerals,Metallurgy and Materials 2012年第8期19卷 711-716页

作者： Rong-ting Xiao hao yu Ping Zhou School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China Laiwu Iron & Steel Group Co. Ltd. Laiwu 271104 China

The austenite grain growth behavior of Q1030 steel was studied under different heating conditions. The austenite grain size increases with the heating temperature and holding time increasing. Austenite grains grow in an exponential manner with rising heating tem- perature and in a parabolic manner with prolonging holding time. A mathematical model for describing the austenite grain growth behavior of Q 1030 steel was obtained on the basis of experimental results using regression analysis. When the heating temperatures lie between 1000 and 1100℃ at a certain holding time, abnormal grain growth appears, which causes mixed grains in Q1030 steel.

关键词： high strength steel heat treatment austenite grain size grain growth mathematical models

Evolutionary Significance of Pylentonemid Radiolarians and Their Late Devonian Species from Southwestern Tianshan,China

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Acta Geologica Sinica(English Edition) 2006年第5期80卷 647-655页

作者： LIU yu hao Shougang Department of Geology Peking University Beijing 100871

A group of radiolarian fossils with a complete morphological gradient of increasing polarization are reported from upper Devonian successions in southwestern Tianshan, China. Specifically, the important transitional mophotypes, Pylentonema transitorum sp. nov., Archocyrtium medium sp. nov. and Quadrapesus transitivus sp. nov, were found. Based on the fact that the new transitional radiolarian fossils resemble more closely to pylentonemids （cyrtoid nassellarians） than to entactinids （spumellarians） in morphology, they are assigned to pylentonemids. Pylentonemids share characters of both the Nassellaria （e.g., horned cephalis, basal opening with pylome） and Spumellaria （e.g., system of trabecular spicules）, and they are thus of evolutionary significance. The evolutionary trend from spumellarians to nassellarians is characterized by （1） internal spicule： from simple trabecular spicules to complicate components （A;Ir,II;D;V;Lr,Li;MB）; （2） polarization of the radiolarian tests due to rearrangment of spine, from radial to an axial symmetry; （3） the gradual formation of a basal opening （aperture, pylome, or podome）; and the transition from a pseudopylome, a primative pylome with a narrow margin on the outer shell, to a true pylome rimmed with a narrow, elevated impermite wall.

关键词： radiolarian spumellarian nassellarian entactinids pylentonemids phylogenetic evolution Late Devonian southwestern Tianshan

Formulation and Interpretation of International Diagnostic Guidelines for Blood-Stasis Syndrome

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Chinese Journal of Integrative Medicine 2022年第4期28卷 291-296页

作者： QIU yu XU hao Xiyuan Hospital China Academy of Chinese Medical SciencesBeijing100091China

Blood-stasis syndrome refers to the syndrome caused by poor blood circulation,blood stasis,or blood overflowing outside the vessels and accumulating in the *** main clinical manifestations are pain,lump,bleeding,dark-purple complexion or cyanosis of lips and tongue,dry and scaly skin,thin and astringent or intermittent ***-stasis syndrome is a common basic syndrome in traditional Chinese medicine(TCM).

关键词： medicine(TCM) Blood stasis

Platinum-based ternary catalysts for the electrooxidation of ethanol

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Particuology 2021年第5期19卷 169-186页

作者： Guangxing Yang Qiao Zhang hao yu Feng Peng State Key Laboratory of Pulp and Paper Engineering South China University of TechnologyGuangzhou 510641PR China School of Chemistry and Chemical Engineering South China University of TechnologyGuangzhou 510641PR China School of Chemistry and Chemical Engineering Guangzhou UniversityGuangzhou 510006PR China

Direct ethanol fuel cell(DEFC)as a promising device for converting chemical energy to electricity has been paid ever-increasing ***,the slow kinetics of ethanol electrooxidation at an anode hinders the application of *** Pt is the best catalyst among all the pure metal catalysts,it still has a relatively poor ability to break the Csingle bondC bond,is deactivated by the accumulated CO_(ad) intermediates,and undergoes unwanted desired structure change over long-term *** recent years,the addition of other metals to form binary,ternary,and quaternary catalysts have significantly improved electroactivity and *** catalysts can have numerous element combinations and complicated architectures and,therefore,have been the subject of considerable *** this review,most of the reported ternary catalysts will be summarized and categorized according to their structure while discussing the essence of the role of each component.

关键词： Direct ethanol fuel cell Ethanol oxidation reaction Ternary catalyst Composition-reactivity relationship

Inverse determination of multiple heat sources’ release history in indoor environments

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Building Simulation 2021年第4期14卷 1263-1275页

作者： Lei Lei hao Zheng Bing Wu yu Xue School of Architecture and Transportation Engineering Guilin University of Electronic Technology1 Jinji RoadGuilin541004China School of Civil Engineering Dalian University of Technology2 Linggong RoadDalian116024China

The heat source of an air-conditioned room has an important effect on the indoor environment. The release rates of heat sources are related to the comfort of the designed thermal environment, so they must be determined. Traditional design methods rely on iterative guess-and-correct, which consumes resources and time and cannot meet the needs of modern design. This study aims to establish an inverse model of Tikhonov regularization and least square optimization by using computational fluid dynamics (CFD), so that researchers can accurately determine the time release rate of multiple heat sources with known parameters. The temporal release rates can then be solved based on the inverse matrix operation with the temperature series at different discrete times. The study speeds up the solving process and expresses the temperature as the convolution integral between the temperature response of the thermal response factor and the arbitrary release rate. The results show that applying the above method to the quantization of the temporal release rates of three heat sources in a three-dimensional cavity can correctly determine the temporal release rates of multiple heat sources. The errors between the inversely determined release rates and the actual release rates are less than 40%.

关键词： inverse model multiple heat sources temporal release rate inverse matrix CFD