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Solution of the Nucleon Structure Problem from a Field Theory of Fermions and Bosons and the Origin of the Proton Stability
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作者 Hans-Peter Morsch 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第4期1655-1669,共15页
A bound state formalism derived from a fermion-boson symmetric Lagrangian has been used to calculate the nucleon masses, the charge neutrality of the neutron, the magnetic moments and the electromagnetic form factor r... A bound state formalism derived from a fermion-boson symmetric Lagrangian has been used to calculate the nucleon masses, the charge neutrality of the neutron, the magnetic moments and the electromagnetic form factor ratios μpGEp/GMpand μnGEn/GMn. A quantitative description is obtained, assuming a mixing of a scalar bound state of 3(f f¯)fstructure with its corresponding vector (f f¯)fstate (f indicating massless elementary fermions). Only a few parameters are needed, mainly fixed by energy and momentum conservation. The nucleon stability is explained by an extra binding in the confinement potential, negative for electric and positive for magnetic binding of the proton, and opposite for the neutron. The stronger electric extra binding of the proton allows a decay of the neutron to proton and electron. 展开更多
关键词 Proton and Neutron Properties Described in a New Bound State Formalism by a Mixing of Two Related Bound States Quantitative Agreement with Their Masses RADII magnetic Moments and Electromagnetic Form factor Ratios High Stability Due to Extra Binding in the Confinement Potential
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Epidermal growth factor receptor-targeted ultra-small superparamagnetic iron oxide particles for magnetic resonance molecular imaging of lung cancer cells in vitro 被引量:7
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作者 CHEN Chun-li HU Guang-yuan +3 位作者 MEI Qi QIU Hong LONG Guo-xian HU Guo-qing 《Chinese Medical Journal》 SCIE CAS CSCD 2012年第13期2322-2328,共7页
Background Magnetic resonance (MR) molecular imaging can detect abnormalities associated with disease at the level of cell and molecule. The epidermal growth factor receptor (EGFR) plays an important role in the d... Background Magnetic resonance (MR) molecular imaging can detect abnormalities associated with disease at the level of cell and molecule. The epidermal growth factor receptor (EGFR) plays an important role in the development of lung cancer. This study aimed to explore new MR molecular imaging targeting of the EGFR on lung cancer cells. Methods We attached ultra-small superparamagnetic iron oxide (USPIO) particles to cetuximab (C225) anti-human IgG using the carbodiimide method. We made the molecular MR contrast agents C225-USPIO and IgG-USPIO, the latter as a control reagent, and determined concentrations according to the Fe content. Lung cancer A549 cells were cultured and immunocytochemistry (SP) was used to detect the expression of EGFR on cells. We detected the binding rate of C225-USPIO to A549 cells with immunofluorescence staining and flow cytometry. We cultured A549 cells with C225-USPIO at a Fe concentration of 50 pg/ml and assayed the binding of C225-USPIO after 1 hour with Prussian blue staining and transmission electron microscopy (TEM). We determined the effects on imaging of the contrast agent targeted to cells using a 4.7T MRI. We did scanning on the cells labeled with C225-USPIO, IgG-USPIO, and distilled water, respectively. The scanning sequences included axial T1WI, T2WI. Results Immunocytochemical detection of lung cancer A549 cells found them positive for EGFR expression. Immunofluorescence staining and flow cytometry after cultivation with different concentrations of C225-USPIO showed the binding rate higher than the control. Prussian blue staining and transmission electron microscopy revealed that in the C225-USPIO contrast agent group of cells the particle content of Fe in cytoplasmic vesicles or on surface was more than that in the control group. The 4.7T MR imaging (MRI) scan revealed the T2WI signal in the C225-USPIO group of cells decreased significantly more than in unlabeled cells, but there was no significant difference between the time gradients. Conclusions We successfully constructed the molecular imaging agent C225-USPIO targeting the EGFR of A549 lung cancer cells. The imaging agent showed good targeting effect and specificity, and reduced MRI T2 value significantly, thus such molecular contrast agents could provide a new way to measure EGFR levels. 展开更多
关键词 ultra-small superparamagnetic iron oxide epidermal growth factor receptor magnetic resonance imaging target
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Design of a Transverse-flux Permanent-magnet Linear Generator and Controller for Use with a Free-piston Stirling Engine 被引量:2
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作者 ZHENG Jigui HUANG Yuping +1 位作者 WU Hongxing ZHENG Ping 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第4期832-842,共11页
Transverse-flux with high efficiency has been applied in Stirling engine and permanent magnet synchronous linear generator system,however it is restricted for large application because of low and complex process.A nov... Transverse-flux with high efficiency has been applied in Stirling engine and permanent magnet synchronous linear generator system,however it is restricted for large application because of low and complex process.A novel type of cylindrical,non-overlapping,transverse-flux,and permanent-magnet linear motor(TFPLM) is investigated,furthermore,a high power factor and less process complexity structure research is developed.The impact of magnetic leakage factor on power factor is discussed,by using the Finite Element Analysis(FEA) model of stirling engine and TFPLM,an optimization method for electro-magnetic design of TFPLM is proposed based on magnetic leakage factor.The relation between power factor and structure parameter is investigated,and a structure parameter optimization method is proposed taking power factor maximum as a goal.At last,the test bench is founded,starting experimental and generating experimental are performed,and a good agreement of simulation and experimental is achieved.The power factor is improved and the process complexity is decreased.This research provides the instruction to design high-power factor permanent-magnet linear generator. 展开更多
关键词 permanent-magnet linear motor(TFPLM) stirling engine magnetic leakage factor power factor
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Performance investigation of plasma magnetohydrodynamic power generator 被引量:1
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作者 Hulin HUANG Linyong LI +1 位作者 Guiping ZHU Lai LI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2018年第3期423-436,共14页
A magnetohydrodynamic (MHD) power generator system involves several subjects such as magnetohydrodynamics, plasma physics, material science, and structure mechanics. Therefore, the performance of the MHD power gener... A magnetohydrodynamic (MHD) power generator system involves several subjects such as magnetohydrodynamics, plasma physics, material science, and structure mechanics. Therefore, the performance of the MHD power generator is affected by many factors, among which the load coefficient k is of great importance. This paper reveals the effect of some system parameters on the performance by three-dimensional (3D) numerical simulation for a Faraday type MHD power generator using He/Xe as working plasma. The results show that average electrical conductivity increases first and then decreases with the addition of magnetic field intensity. Electrical conductivity reaches the maximum value of 11.05 S/m, while the applied magnetic field strength is B = 1.75 T. When B 〉 3 T, the ionization rate along the midline well keeps stable, which indicates that the ionization rate and three-body recombination rate (three kinds of particles combining to two kinds of particles) are approximately equal, and the relatively stable plasma structure of the mainstream is preserved. Efficiency of power generation of the Faraday type channel increases with an increment of the load factor. However, enthalpy extraction first increases to a certain value, and then decreases with the load factor. The enthalpy extraction rate reaches the maximum when the load coefficient k equals 0.625, which is the best performance of the power generator channel with the maximum electricity production. 展开更多
关键词 magnetohydrodynamic (MHD) power generator Faraday type generatorchannel ionization load factor magnetic field
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Comparative studies on nuclear elastic magnetic form factors between the relativistic and non-relativistic mean-field approaches
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作者 Xin Li Yunsheng Wang +3 位作者 Xiaoyong Guo Meina Chen Jian Liu Chang Xu 《Chinese Physics C》 SCIE CAS CSCD 2022年第1期167-179,共13页
It is known that elastic magnetic electron scattering can be used to study the magnetic properties of nuclei and determine the outermost-shell single-particle orbitals.In this study,the magnetic form factors|F_(M)(q)|... It is known that elastic magnetic electron scattering can be used to study the magnetic properties of nuclei and determine the outermost-shell single-particle orbitals.In this study,the magnetic form factors|F_(M)(q)|^(2)of odd-A nuclei calculated with relativistic and non-relativistic models are systematically compared.We use the relativistic mean-field(RMF)and Skyrme Hartree-Fock(SHF)models to generate single-particle wave functions and calculate the|F_(M)(q)|^(2)values of selected nuclei under relativistic and non-relativistic frameworks,respectively.Geometric factors are introduced through the spherical limit method to consider the influences of deformation,which improves the agreement between the theoretical results and experimental data.It is shown that both the models have the capability to describe the magnetic form factors in the spherical and deformed cases,and the discrepancies in|F_(M)(q)|^(2)reflect the differences in the descriptions of the single-particle orbital between the two models. 展开更多
关键词 magnetic form factors single-particle wave function mean-field model
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Analysis of iris-loaded resonance cavity in miniaturized maser
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作者 Zu-Gen Guo Yong Zhang +4 位作者 Tao Tang Zhan-Liang Wang Yu-Bin Gong Fei Xiao Hua-Rong Gong 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第5期188-193,共6页
The size reduction of atomic clocks is a long-standing research issue.Many atomic clocks such as passive hydrogen masers(PHMs)and compact rubidium masers(CRMs)use iris-loaded resonance cavities(IRCs)as their microwave... The size reduction of atomic clocks is a long-standing research issue.Many atomic clocks such as passive hydrogen masers(PHMs)and compact rubidium masers(CRMs)use iris-loaded resonance cavities(IRCs)as their microwave cavities because they can dramatically reduce the radical sizes of the atomic clocks.In this paper,the electromagnetic characteristic of the IRC is investigated by a theoretical model based on electromagnetic field theory.The formulas to calculate the resonance frequency,quality factor,and magnetic energy filling factor are presented.The relationship between the IRC structure and its electromagnetic characteristic is clarified.The theoretical calculation results accord well with the electromagnetic software simulations and experimental results.The results in this paper should be helpful in understanding the physical mechanism of the IRC and designing the atomic clocks. 展开更多
关键词 MASER iris-loaded resonance cavity resonance frequency quality factor magnetic energy filling factor
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Magnetic properties and magnetic exchange interactions in Gd_(1–x)RE_x(RE=Pr,Nd) alloys 被引量:1
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作者 肖素芬 陈云贵 《Journal of Rare Earths》 SCIE EI CAS CSCD 2016年第5期489-494,共6页
The effect of Pr,Nd addition on the magnetic properties and magnetic exchange interaction of gadolinium alloys was systematically studied.Curie temperature TC and magnetic moment of Gd(1–x)REx(RE=Pr,Nd)systems wi... The effect of Pr,Nd addition on the magnetic properties and magnetic exchange interaction of gadolinium alloys was systematically studied.Curie temperature TC and magnetic moment of Gd(1–x)REx(RE=Pr,Nd)systems with x〈0.05 were investigated.When x〈0.05,Pr and Nd formed respectively with Gd continuous solid solution which has the crystalline structure HCP.Study on the magnetic behavior indicated that at near room temperature,the simple ferromagnetism prevailed in these two systems of alloy.The Curie temperature and magnetic moment of Gd(1–x)REx alloy decreased with RE(RE= Pr,Nd)content x increasing.The de Gennes factor of Gd(1–x)REx alloy which was associated with the exchange interaction between magnetic spin components also decreased with RE content increasing.The above results showed that the magnetic exchange interaction between magnetic atoms in gadolinium could be effectively changed by the Pr,Nd addition. 展开更多
关键词 Gd(1–x)REx(RE=Pr Nd)alloys Curie temperature magnetic moment de Gennes factor G rare earths
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Lattice results on nucleon/roper properties
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作者 Huey-Wen Lin 《Chinese Physics C》 SCIE CAS CSCD 2009年第12期1238-1243,共6页
In this proceeding, I review the attempts to calculate the Nucleon resonance (including Roper as first radially excited state of nucleon and other excited states) using lattice quantum chromodynamics (QCD). The la... In this proceeding, I review the attempts to calculate the Nucleon resonance (including Roper as first radially excited state of nucleon and other excited states) using lattice quantum chromodynamics (QCD). The latest preliminary results from Hadron Spectrum Collaboration (HSC) with mπ≈ 380 MeV are reported. The Sachs electric form factor of the proton and neutron and their transition with the Roper at large Q2 are also updated in this work. 展开更多
关键词 nucleon excited spectroscopy electric and magnetic form factor transposition form factor
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