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Constraining Neutrino Mass in Dynamical Dark Energy Cosmologies with the Logarithm Parametrization and the Oscillating Parametrization 被引量:2
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作者 Tian-Ying Yao Rui-Yun Guo Xin-Yue Zhao 《Journal of High Energy Physics, Gravitation and Cosmology》 2023年第4期1044-1061,共18页
We constrain two dynamical dark energy models that are parametrized by the logarithm form of and the oscillating form of . Comparing with the Chevallier-Polarski-Linder (CPL) model, the two parametrizations for dark e... We constrain two dynamical dark energy models that are parametrized by the logarithm form of and the oscillating form of . Comparing with the Chevallier-Polarski-Linder (CPL) model, the two parametrizations for dark energy can explore the whole evolution history of the universe properly. Using the current mainstream observational data including the cosmic microwave background data and the baryon acoustic oscillation data as well as the type Ia supernovae data, we perform the X<sup>2</sup> statistic analysis to global fit these models, finding that the logarithm parametrization and the oscillating parameterization are almost as well as the CPL scenario in fitting these data. We make a comparison for the impacts of the dynamical dark energy on the cosmological constraints on the total mass of active neutrinos. We find that the logarithm parametrization and the oscillating parameterization can increase the fitting values of Σm<sub>v</sub>. Looser constraints on Σm<sub>v</sub> are obtained in the logarithm and oscillating models than those derived in the CPL model. Consideration of the possible mass ordering of neutrinos reveals that the most stringent constraint on Σm<sub>v</sub> appears in the degenerate hierarchy case. 展开更多
关键词 Dynamical dark Energy Neutrino mass Observational Constraints
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Unified Description of the Three Stable Particles in Self-Action Allows Determination of Their Relative Masses
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作者 Yair Goldin Halfon 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期185-196,共12页
The Dirac equation γ<sub>μ</sub>(δ<sub>μ</sub>-eA<sub>μ</sub>)Ψ=mc<sup>2</sup>Ψ describes the bound states of the electron under the action of external potentials... The Dirac equation γ<sub>μ</sub>(δ<sub>μ</sub>-eA<sub>μ</sub>)Ψ=mc<sup>2</sup>Ψ describes the bound states of the electron under the action of external potentials, A<sub>μ</sub>. We assumed that the fundamental form of the Dirac equation γ<sub>μ</sub>(δ<sub>μ</sub>-S<sub>μ</sub>)Ψ=0 should describe the stable particles (the electron, the proton and the dark-matter-particle (dmp)) bound to themselves under the action of their own potentials S<sub>μ</sub>. The new equation reveals that self energy is consequence of self action, it also reveals that the spin angular momentum is consequence of the dynamic structure of the stable particles. The quantitative results are the determination of their relative masses as well as the determination of the electromagnetic coupling constant. 展开更多
关键词 Electron in Self Action Electron-dark-Matter Particle mass Ratio Analytic Description dark-Matter-Particle
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Unraveling the Quantum Web: The Vortex Theory of Mass and Matter Formation
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作者 Nader Butto 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第3期1195-1225,共31页
Mass plays a role in many physical phenomena, including the behavior of subatomic particles, the formation and behavior of stars and galaxies, and gravitational interactions between objects. The density of vacuum, 9.5... Mass plays a role in many physical phenomena, including the behavior of subatomic particles, the formation and behavior of stars and galaxies, and gravitational interactions between objects. The density of vacuum, 9.5 × 10−27 kg/m3, is a crucial parameter in the theory of cosmic inflation and is responsible for the accelerated expansion of the universe in its early stages. This vacuum energy interacts with matter and manifests itself as mass, which can be described as flow and vortex formation using the laws of hydrodynamics. The vortex model of elementary particles, in conjunction with the laws of hydrodynamics, provides an elegant explanation for the origin of mass and the relationship between mass and energy, with profound implications for the behavior of objects at high velocities and strong gravitational fields. The vacuum behaves as a compressible superfluid, thus elementary particles can be described as vortices of the vacuum. The equations of hydrodynamics for vortices can be applied to describe the nature and value of the mass of particles. The implications of understanding the nature of mass are vast and profound. From elucidating the fundamental properties of particles to informing the design of advanced materials and technologies, this knowledge is indispensable. It drives advancements across numerous fields, transforming both our theoretical understanding and practical capabilities. Continued research into the nature of mass promises to unlock further insights, fostering innovation and expanding the frontiers of science and technology. 展开更多
关键词 dark Energy dark Matter Vacuum mass Subatomic Particles Cosmic Inflation Virtual Particles Vortex Formation HYDRODYNAMICS Density
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Mass Increase with Strong and Gravitational Potentials, and Mass Defect with Electromagnetic Potential
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作者 Hany Ali Hussein 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第3期1079-1094,共16页
The proposal is “mass increases due to strong and gravitational potentials, while it decreases due to Electromagnetic potential”. This proposal explains the big difference in mass between hadrons (protons, neutrons,... The proposal is “mass increases due to strong and gravitational potentials, while it decreases due to Electromagnetic potential”. This proposal explains the big difference in mass between hadrons (protons, neutrons, & mesons) and their components (quarks), mass difference between nucleus and its individual components (protons and neutrons), massless of gamma photons, abnormal masses of mesons and bosons, and the excess in galaxy masses (dark matter). Also, this proposal shows the exact relation between mass and energy: Strong Potential=−3.04mc2| Electric Potential |=−5.57×10−3mc2Gravitational Potential=−1.22×10−7mc2where m represents the excess in mass due to strong potential, or gravitational potential and represents the decrease in mass due to electromagnetic potential. Released energy here equals potential energy and doesn’t equal decrease in mass using the formula E = mc2. Released energy is transferred to heat, photons, kinetic energy… Finally, proposal will try to describe the relation between photon energy and mass of its components using the general equation of kinetic energy: Photon Energy=1/2mc2m is the sum of the individual masses of its components, while the total mass of photon is zero. 展开更多
关键词 mass Defect dark Matter PHOTON Gamma Photon Strong Potential Gravitational Potential Electromagnetic Potential QUARKS Mesons BOSONS Deuterium Proton Neutron
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The Origin, Properties and Detection of Dark Matter and Dark Energy
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作者 Sylwester Kornowski 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第2期749-774,共26页
The pictures from the James Webb Space Telescope (JWST) suggest that massive galaxies were already at the beginning of the expansion of the Universe because there was too short time to create them. It is consistent wi... The pictures from the James Webb Space Telescope (JWST) suggest that massive galaxies were already at the beginning of the expansion of the Universe because there was too short time to create them. It is consistent with the new cosmology presented within the Scale-Symmetric Theory (SST). The phase transitions of the initial inflation field described in SST lead to the Protoworld—its core was built of dark matter (DM). We show that the DAMA/LIBRA annual-modulation amplitude forced by the change of the Earth’s velocity (i.e. baryonic-matter (BM) velocity) in relation to the spinning DM field in our Galaxy’s halo should be very low. We calculated that in the DM-BM weak interactions are created single and entangled spacetime condensates with a lowest mass/energy of 0.807 keV—as the Higgs boson they can decay to two photons, so we can indirectly detect DM. Our results are consistent with the averaged DAMA/LIBRA/COSINE-100 curve describing the dependence of the event rate on the photon energy in single-hit events. We calculated the mean dark-matter-halo (DMH) mass around quasars, we also described the origin of the plateaux in the rotation curves for the massive spiral galaxies, the role of DM-loops in magnetars, the origin of CMB, the AGN-jet and galactic-halo production, and properties of dark energy (DE). 展开更多
关键词 New Cosmology dark Matter DM-BM Weak Interactions DMH mass around Quasars Rotation Curves of Galaxies MAGNETARS CMB AGN-Jet Production Galactic-Halo Production dark Energy
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Simulations and Measurements of Warm Dark Matter Free-Streaming and Mass 被引量:2
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作者 Bruce Hoeneisen 《International Journal of Astronomy and Astrophysics》 2019年第4期368-392,共25页
We compare simulated galaxy distributions in the cold &Lambda;CDM and warm ΛWDM dark matter models. The ΛWDM model adds one parameter to the &Lambda;CDM model, namely the cut-off wavenumber kfs of linear den... We compare simulated galaxy distributions in the cold &Lambda;CDM and warm ΛWDM dark matter models. The ΛWDM model adds one parameter to the &Lambda;CDM model, namely the cut-off wavenumber kfs of linear density perturbations. The challenge is to measure kfs. This study focuses on “smoothing lengths” &pi;/kfs in the range from 12 Mpc to 1 Mpc. The simulations reveal two distinct galaxy populations at any given redshift z: hierarchical galaxies that form bottom up starting at the transition mas?Mfs, and stripped down galaxies that lose mass to neighboring galaxies during their formation, are near larger galaxies, often have filamentary distributions, and seldom fill voids. We compare simulations with observations, and present four independent measurements of kfs, and the mass mh of dark matter particles, based on the redshift of first galaxies, galaxy mass distributions, and rotation curves of spiral galaxies. 展开更多
关键词 dark MATTER mass WARM dark MATTER Free-Streaming GALAXY mass Distribution Spiral GALAXY Adiabatic Invariant
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Cold or Warm Dark Matter?: A Study of Galaxy Stellar Mass Distributions 被引量:3
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作者 Bruce Hoeneisen 《International Journal of Astronomy and Astrophysics》 2020年第2期57-70,共14页
We compare the observed galaxy stellar mass distributions in the redshift range <img src="Edit_bc01f6dd-d7f9-42f9-9db0-dbd1148de50e.png" alt="" />with expectations of the cold ΛCDM and warm ... We compare the observed galaxy stellar mass distributions in the redshift range <img src="Edit_bc01f6dd-d7f9-42f9-9db0-dbd1148de50e.png" alt="" />with expectations of the cold ΛCDM and warm ΛWDM dark matter models, and obtain the warm dark matter cut-off wavenumber: <img src="Edit_ab3d491d-7145-4d59-b4b1-bea473d62333.png" alt="" />. This result is in agreement with the independent measurements with spiral galaxy rotation curves, confirms that <em>k</em><sub>fs</sub> is due to warm dark matter free-streaming, and is consistent with the scenario of dark matter with no freeze-in and no freeze-out. Detailed properties of warm dark matter can be derived from <em>k</em><sub>fs</sub>. The data disfavors the ΛCDM model. 展开更多
关键词 dark Matter Warm dark Matter dark Matter Properties Galaxy Stellar mass
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Measurement of the Dark Matter Velocity Dispersion with Galaxy Stellar Masses, UV Luminosities, and Reionization 被引量:1
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作者 Bruce Hoeneisen 《International Journal of Astronomy and Astrophysics》 2022年第3期258-272,共15页
The root-mean-square of non-relativistic warm dark matter particle velocities scales as v<sub>hrms</sub>(a)=v<sub>hrms</sub>(1)/a , where a is the expansion parameter of the universe. This velo... The root-mean-square of non-relativistic warm dark matter particle velocities scales as v<sub>hrms</sub>(a)=v<sub>hrms</sub>(1)/a , where a is the expansion parameter of the universe. This velocity dispersion results in a cut-off of the power spectrum of density fluctuations due to dark matter free-streaming. Let k<sub>fs </sub>(t<sub>eq</sub>) be the free-streaming comoving cut-off wavenumber at the time of equal densities of radiation and matter. We obtain , and , at 68% confidence, from the observed distributions of galaxy stellar masses and rest frame ultra-violet luminosities. This result is consistent with reionization. From the velocity dispersion cut-off mass we obtain the limits v<sub>hrms</sub>(1)k<sub>fs </sub>(t<sub>eq</sub>) >1.5 Mpc<sup>-1</sup>. These results are in agreement with previous measurements based on spiral galaxy rotation curves, and on the formation of first galaxies and reionization. These measured parameters determine the temperature-to-mass ratio of warm dark matter. This ratio happens to be in agreement with the no freeze-in and no freeze-out warm dark matter scenario of spin 0 dark matter particles decoupling early on from the standard model sector. Spin 1/2 and spin 1 dark matter are disfavored if nature has chosen the no freeze-in and no freeze-out scenario. An extension of the standard model of quarks and leptons, with scalar dark matter that couples to the Higgs boson that is in agreement with all current measurements, is briefly reviewed. Discrepancies with limits on dark matter particle mass that can be found in the literature are addressed. 展开更多
关键词 Warm dark Matter Galaxy Stellar mass Galaxy UV Luminosity REIONIZATION
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Inflation, Dark Energy, Acceleration, Missing Mass?
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作者 P. Christillin 《Journal of Modern Physics》 2021年第6期806-828,共23页
The black hole (b.h.) model based on the strong field treatment of the Newton potential is presented. The essential role of self energy both at the Planck level and for matter and radiation at later stages supports th... The black hole (b.h.) model based on the strong field treatment of the Newton potential is presented. The essential role of self energy both at the Planck level and for matter and radiation at later stages supports the picture of an expanding Universe necessarily accompanied by particle creation if energy conservation applies at every scale. This process is shown to provide a gravitational repulsive force which can counterbalance gravitational attraction thus allowing the possibility of a steady expansion. This black hole treatment of our Universe evolution, questions the necessity of inflation. The role of the critical density to dictate the fate of the Universe is replaced by the black hole condition which entails a different relation between Hubble parameter and density thus disposing of dark energy. Since its predictions provide a different time development of the Universe also the evidence for its acceleration is disputed. That seems to provide a coherent scheme for our picture of the Universe evolution, based on Hubble’s law and backed up by the consideration of inertial forces. Newtonian angular momentum is also not conserved at cosmological scales. Finally we consider two coordinates systems. The conformally flat coordinates are shown to disprove inflation and the relevance of the Painleve-Gullstrand metric in providing global coordinates is underlined. The combined effect of Hubble expansion and of proper time also questions the existence of missing mass. 展开更多
关键词 Cosmogony Black Hole Particle Creation INFLATION dark Energy Missing mass
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A Unifying Theory of Dark Energy, Dark Matter, and Baryonic Matter in the Positive-Negative Mass Universe Pair: Protogalaxy and Galaxy Evolutions
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作者 Ding-Yu Chung 《Journal of Modern Physics》 2020年第7期1091-1122,共32页
This paper modifies the Farnes’ unifying theory of dark energy and dark matter which are negative-mass, created continuously from the negative-mass universe in the positive-negative mass universe pair. The first modi... This paper modifies the Farnes’ unifying theory of dark energy and dark matter which are negative-mass, created continuously from the negative-mass universe in the positive-negative mass universe pair. The first modification explains that observed dark energy is 68.6%, greater than 50% for the symmetrical positive-negative mass universe pair. This paper starts with the proposed positive-negative-mass 11D universe pair (without kinetic energy) which is transformed into the positive-negative mass 10D universe pair and the external dual gravities as in the Randall-Sundrum model, resulting in the four equal and separate universes consisting of the positive-mass 10D universe, the positive-mass massive external gravity, the negative-mass 10D universe and the negative-mass massive external gravity. The positive-mass 10D universe is transformed into 4D universe (home universe) with kinetic energy through the inflation and the Big Bang to create positive-mass dark matter which is five times of positive-mass baryonic matter. The other three universes without kinetic energy oscillate between 10D and 10D through 4D, resulting in the hidden universes when D > 4 and dark energy when D = 4, which is created continuously to our 4D home universe with the maximum dark energy = 3/4 = 75%. In the second modification to explain dark matter in the CMB, dark matter initially is not repulsive. The condensed baryonic gas at the critical surface density induces dark matter repulsive force to transform dark matter in the region into repulsive dark matter repulsing one another. The calculated percentages of dark energy, dark matter, and baryonic matter are 68.6 (as an input from the observation), 26 and 5.2, respectively, in agreement with observed 68.6, 26.5 and 4.9, respectively, and dark energy started in 4.33 billion years ago in agreement with the observed 4.71 <span style="white-space:nowrap;">&plusmn;</span> 0.98 billion years ago. In conclusion, the modified Farnes’ unifying theory reinterprets the Farnes’ equations, and is a unifying theory of dark energy, dark matter, and baryonic matter in the positive-negative mass universe pair. The unifying theory explains protogalaxy and galaxy evolutions in agreement with the observations. 展开更多
关键词 Unifying Theory Farnes dark Energy dark Matter Baryonic Matter Negative mass Positive-Negative mass Universe Pair Protogalaxy Evolution Galaxy Evolution
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Solving the Olbers’s Paradox, Explaining the “Red-Shift”, and Challenging the Relativities by “Sun Matters Theory” and “Sun Model of Universe”, an Evolution of the Einstein’s Static Universe Model
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作者 Wanpeng Sun 《Natural Science》 2024年第2期7-18,共12页
Olbers’s paradox, known as the dark night paradox, is an argument in astrophysics that the darkness of the night sky conflicts with the assumption of an infinite and eternal static universe. Big-Bang theory was used ... Olbers’s paradox, known as the dark night paradox, is an argument in astrophysics that the darkness of the night sky conflicts with the assumption of an infinite and eternal static universe. Big-Bang theory was used to partially explain this paradox, while introducing new problems. Hereby, we propose a better theory, named Sun Matters Theory, to explain this paradox. Moreover, this unique theory supports and extended the Einstein’s static universe model proposed by Albert Einstein in 1917. Further, we proposed our new universe model, “Sun Model of Universe”. Based on the new model and novel theory, we generated innovative field equation by upgrading Einstein’s Field Equation through adding back the cosmological constant, introducing a new variable and modifying the gravitationally-related concepts. According to the Sun Model of Universe, the dark matter and dark energy comprise the so-called “Sun Matters”. The observed phenomenon like the red shift is explained as due to the interaction of ordinary light with Sun Matters leading to its energy and frequency decrease. In Sun Model, our big universe consists of many universes with ordinary matter at the core mixed and surrounded with the Sun Matters. In those universes, the laws of physics may be completely or partially different from that of our ordinary universe with parallel civilizations. The darkness of night can be easily explained as resulting from the interaction of light with the Sun Matters leading to the sharp decrease in the light intensity. Sun Matters also scatter the light from a star, which makes it shining as observed by Hubble. Further, there is a kind of Sun Matters named “Sun Waters”, surrounding every starts. When lights pass by the sun, the Sun Waters deflect the lights to bend the light path. According to the Sun Model, it is the light bent not the space bent that was proposed in the theory of relativities. 展开更多
关键词 Olbers’s Paradox Sun Matters Theory Sun Model of Universe Einstein’s Universe dark mass
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Dark Matter Particles
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作者 Vladimir S. Netchitailo 《Journal of High Energy Physics, Gravitation and Cosmology》 2023年第4期1004-1020,共17页
Researchers have been able to infer the existence of Dark Matter (DM) only from the gravitational effect. DM seems to outweigh visible matter roughly six to one, making up about 27% of the universe. Here’s a sobering... Researchers have been able to infer the existence of Dark Matter (DM) only from the gravitational effect. DM seems to outweigh visible matter roughly six to one, making up about 27% of the universe. Here’s a sobering fact: The matter we know and that makes up all stars and galaxies only accounts for 5% of the content of universe! But what is DM? [1]. Many experiments to detect and study Dark Matter Particles (DMPs) directly are being actively undertaken, but none have yet succeeded. Indirect detection experiments search for the products of the annihilation or decay of DMPs in outer space [2]. In this paper, we discuss main ideas of the Hypersphere World-Universe Model (WUM) and introduce an additional new DMP “XION” (boson) with the rest energy 10.6 μeV that is an analog of Axion. On June 28, 2023, it was announced the existence of Cosmic Gravitational Background. In frames of WUM, we give an explanation of this discovery based on the analysis of “Gravitoplasma” composed of objects with Planck mass, which were created as the result of Weak Interaction between XIONs and other particles in the Medium. 展开更多
关键词 World-Universe Model Multicomponent dark Matter Multiworld Planck mass XION Cosmic Gravitational Background Distribution of World’s Energy Density
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Mass of the Universe from Quarks: A Plausible Solution to the Cosmological Constant Problem
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作者 Kevin Oramah 《Journal of Modern Physics》 2023年第12期1672-1692,共21页
A framework to estimate the mass of the universe from quarks is presented, taking spacetime into account. This is a link currently missing in our understanding of physics/science. The focus on mass-energy balance is a... A framework to estimate the mass of the universe from quarks is presented, taking spacetime into account. This is a link currently missing in our understanding of physics/science. The focus on mass-energy balance is aimed at finding a solution to the Cosmological Constant (CC) problem by attempting to quantize space-time and linking the vacuum energy density at the beginning of the universe and the current energy density. The CC problem is the famous disagreement of approximately 120 orders of magnitude between the theoretical energy density at the Planck scale and the indirectly measured cosmological energy density. Same framework is also used to determine the mass of the proton and neutron from first principles. The only input is the up quark (u-quark) mass, or precisely, the 1st generation quarks. The method assumes that the u-quark is twice as massive as the down-quark (d-quark). The gap equation is the starting point, introduced in its simplest form. The main idea is to assume that all the particles and fields in the unit universe are divided into quarks and everything else. Everything else means all fields and forces present in the universe. It is assumed that everything else can be “quark-quantized”;that is, assume that they can be quantized into similar sizeable u-quarks and/or it’s associated interactions and relations. The result is surprisingly almost as measured and known values. The proton structure and mass composition are also analysed, showing that it likely has more than 3 quarks and more than 3 valence quarks. It is also possible to estimate the percentage of dark matter, dark energy, ordinary matter, and anti-matter. Finally, the cosmological constant problem or puzzle is resolved by connecting the vacuum energy density of Quantum Field Theory (5.1E+96 kg/m<sup>3</sup>) and the energy density of General Relativity (1.04E−26 kg/m<sup>3</sup>). Upon maturation, this framework can serve as a bridging platform between Quantum Field Theory and General Relativity. Other aspects of natures’ field theories can be successfully ported to the platform. It also increases the chances of solving some of the unanswered questions in physics. 展开更多
关键词 Cosmological Constant Proton mass-Structure Quark-Quantization dark Matter dark Energy Age of the Universe Energy Density Spacetime Quantization
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非均匀GaAs/AlGaAs量子阱红外探测器材料表征和器件性能研究
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作者 苏家平 周孝好 +4 位作者 唐舟 范柳燕 夏顺吉 陈平平 陈泽中 《红外与毫米波学报》 SCIE EI CAS CSCD 北大核心 2024年第1期7-14,共8页
本文利用分子束外延(MBE)技术成功生长了GaAs/AlGaAs非均匀量子阱红外探测器材料,并对相关微结构作了细致表征。分析比较了非均匀量子阱结构和常规量子阱红外探测器性能差异,并对比研究了不同势阱宽度下非均匀量子阱红外探测器的性能变... 本文利用分子束外延(MBE)技术成功生长了GaAs/AlGaAs非均匀量子阱红外探测器材料,并对相关微结构作了细致表征。分析比较了非均匀量子阱结构和常规量子阱红外探测器性能差异,并对比研究了不同势阱宽度下非均匀量子阱红外探测器的性能变化。通过高分辨透射电子显微镜(HRTEM)结合能谱仪(EDS)对非均匀量子阱红外探测器材料微结构进行了分析,并利用二次离子质谱仪(SIMS)对非均匀势阱掺杂进行了表征。结果表明,该量子阱外延材料晶体质量很好,量子阱结构和掺杂浓度也与设计值符合较好。对于非均匀量子阱红外探测器,通过改变每个阱的掺杂浓度和势垒宽度,可以改变量子阱电场分布,而与传统的均匀量子阱红外探测器相比,其暗电流显著下降(约一个数量级)。在不同阱宽下,非均匀量子阱的跃迁模式发生改变,束缚态到准束缚态跃迁模式下(B-QB)的器件具有较高的黑体响应率以及较低的暗电流。 展开更多
关键词 非均匀 量子阱 高分辨电镜 二次离子质谱 暗电流
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结构高位带暗梁厚板式转换层施工技术探析
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作者 钟正飞 《江西建材》 2024年第5期285-287,共3页
文中以某大型公共建筑为例,对该项目带暗梁厚板式转换层施工要点进行分析,提出结构高位带暗梁厚板式转换层施工方案。结果表明,并筋处理及钢筋分段施工能有效解决钢筋密集、安装困难的问题;板厚较大时,采用上下层混凝土分层浇筑的方式,... 文中以某大型公共建筑为例,对该项目带暗梁厚板式转换层施工要点进行分析,提出结构高位带暗梁厚板式转换层施工方案。结果表明,并筋处理及钢筋分段施工能有效解决钢筋密集、安装困难的问题;板厚较大时,采用上下层混凝土分层浇筑的方式,可减少模板及支架压力;上下部结合处设置附加钢筋网及拉勾,可提高上下部混凝土的结合能力;大体积混凝土采用优化配合比、分层浇筑及养护到位的措施,可有效减少结构裂缝的出现。 展开更多
关键词 高层建筑 带暗梁厚板 转换层 大体积混凝土
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Characterizations That Help Explain Particle and Cosmic Data
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作者 Thomas Joel Buckholtz 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第3期1304-1357,共54页
This paper suggests explanations for otherwise seemingly unexplained data about elementary particles and cosmology. The explanations have bases in coordinate-based modeling and in integer-based characterizations for s... This paper suggests explanations for otherwise seemingly unexplained data about elementary particles and cosmology. The explanations have bases in coordinate-based modeling and in integer-based characterizations for some catalogs. One catalog features properties—including charge, mass, and angular momentum—of objects. Another catalog features all known and some possible elementary particles. Assumptions include that multipole-expansion mathematics has uses regarding long-range interactions, such as gravity, and that nature includes six isomers of all elementary particles other than long-range-interaction bosons. One isomer associates with ordinary matter. Five isomers are associated with dark matter. Multipole notions help explain large-scale aspects such as the rate of expansion of the universe. 展开更多
关键词 Elementary Particles dark Matter Rate of Expansion of the Universe Galaxy Formation Neutrino masses Vacuum Energy dark Energy Quantum Gravity
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渥堆时间对黟县黑茶滋味品质及非挥发性代谢物的影响
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作者 王辉 周汉琛 +4 位作者 刘亚芹 杨霁虹 张晓磊 徐玉婕 雷攀登 《食品工业科技》 CAS 北大核心 2024年第21期283-291,共9页
为探究渥堆进程中影响黟县黑茶滋味品质变化的关键节点,本研究通过感官评价、氨基酸分析仪、液相色谱及液相色谱质谱联用仪,分析了不同渥堆时间下(0、3、6、9、12、15和18 h)其滋味品质及代谢物的变化。结果表明,渥堆9 h后茶汤苦味开始... 为探究渥堆进程中影响黟县黑茶滋味品质变化的关键节点,本研究通过感官评价、氨基酸分析仪、液相色谱及液相色谱质谱联用仪,分析了不同渥堆时间下(0、3、6、9、12、15和18 h)其滋味品质及代谢物的变化。结果表明,渥堆9 h后茶汤苦味开始降低、收敛性和厚度增加、陈醇风味凸显。儿茶素类物质总量在渥堆期间显著降低,而没食子酸含量则显著增加;咖啡碱含量在渥堆18 h后降低了14.7%;游离氨基酸总量在渥堆后期(15~18 h)呈现上升趋势;黄酮醇及单糖苷的黄酮苷类物质含量在渥堆中期(9~12 h)显著增加(P<0.05);双糖苷的黄酮苷类物质含量则在渥堆中后期呈上升趋势。关键滋味物质分析显示(VIP>1,DOT>1),杨梅素-3-O-半乳糖苷、紫云英苷、异槲皮苷、槲皮素-3-O-芸香糖苷、表没食子儿茶素、表儿茶素、表没食子儿茶素没食子酸酯及咖啡碱是影响黟县黑茶品质变化的重要呈味物质,其中,前三种糖苷类物质在渥堆9~12 h含量显著增高;表没食子儿茶素、表儿茶素在9~12 h期间含量显著降低;表没食子儿茶素没食子酸酯、咖啡碱在渥堆后呈现显著降低;槲皮素-3-O-芸香糖苷在渥堆中期(9~12 h)显著下降,在渥堆15 h后显著增加,是渥堆后期茶汤涩感增加的重要因子。本研究结果为后续黟县黑茶渥堆工艺优化及探究其滋味品质形成机制提供了重要理论参考。 展开更多
关键词 黟县黑茶 渥堆 感官评价 滋味成分 液相色谱质谱
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Fermion or Boson Dark Matter? 被引量:4
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作者 Bruce Hoeneisen 《International Journal of Astronomy and Astrophysics》 2020年第3期203-223,共21页
We measure properties of dark matter in four well motivated scenarios: fermions with ultra-relativistic thermal equilibrium (URTE), bosons with URTE, fermions with non-relativistic thermal equilibrium (NRTE), and boso... We measure properties of dark matter in four well motivated scenarios: fermions with ultra-relativistic thermal equilibrium (URTE), bosons with URTE, fermions with non-relativistic thermal equilibrium (NRTE), and bosons with NRTE. We attempt to discriminate between these four scenarios with studies of spiral galaxy rotation curves, and galaxy stellar mass distributions. The measurements show evidence for boson dark matter with a significance of 3.5σ, and obtain no significant discrimination between URTE and NRTE. 展开更多
关键词 dark Matter Free-Streaming Galaxy mass Distribution Spiral Galaxy
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青砖茶提取物缓解小鼠溃疡性结肠炎机制研究
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作者 叶丹 赵依叶 +1 位作者 苗潇磊 郑敏 《湖北科技学院学报(医学版)》 2024年第5期374-379,共6页
目的探讨青砖茶提取物(QDTE)对葡聚糖硫酸钠(DSS)诱导的溃疡性结肠炎(UC)小鼠肠道中短链脂肪酸(SCFAs)的影响。方法将小鼠随机分为5组(10只/组),正常组、模型组、阳性组、L-QDTE组[200mg/(kg·d)]和H-QDTE组[400mg/(kg·d)],模... 目的探讨青砖茶提取物(QDTE)对葡聚糖硫酸钠(DSS)诱导的溃疡性结肠炎(UC)小鼠肠道中短链脂肪酸(SCFAs)的影响。方法将小鼠随机分为5组(10只/组),正常组、模型组、阳性组、L-QDTE组[200mg/(kg·d)]和H-QDTE组[400mg/(kg·d)],模型组连续9d给予3%DSS,阳性组和QDTE组连续给药16d,第17d处死,收集小鼠粪便,采用液相色谱质谱联用仪测定粪便中衍生化后的SCFAs含量。结果SCFAs含量测定的方法学考察结果均符合要求,QDTE增加UC小鼠肠道中乙酸、丙酸、丁酸、异丁酸、戊酸、异戊酸和己酸含量,其中乙酸、丁酸和异戊酸含量呈现剂量依赖性。结论QDTE可以通过增加SCFAs的含量缓解小鼠UC。 展开更多
关键词 青砖茶提取物 短链脂肪酸 溃疡性结肠炎 液质联用仪
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New Dark Matter Generation Mechanism and Its Implications for the Cosmological Background
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作者 Henk Defloor 《Journal of High Energy Physics, Gravitation and Cosmology》 2017年第4期791-807,共17页
A new concept has been proposed and elaborated to account for recent observations deviating from ΛCDM and ΛWDM. Using an intermediate energy conversion mechanism in the expanding universe and assuming three neutrino... A new concept has been proposed and elaborated to account for recent observations deviating from ΛCDM and ΛWDM. Using an intermediate energy conversion mechanism in the expanding universe and assuming three neutrino families with identical mass, a neutrino mass of eV/c2 has been found as well as a natural explanation for the difference in Hubble constant as measured by WMAP/Planck and obtained from LSS data. The value for the effective number of neutrinos at the time of decoupling is compatible with the Planck result. The age of the universe is slightly younger at Gyr. At late times, the closure parameter for the neutrino radiation drastically increases but still remains well below that of the baryons , among other energy contributions. 展开更多
关键词 NEUTRINO mass dark MATTER COSMOLOGY
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