25 results on '"Minghong Wang"'
Search Results
2. A novel peptide binding to the C-terminal domain of connective tissue growth factor for the treatment of bleomycin-induced pulmonary fibrosis
- Author
-
Minghong Wang, Han Xiao, Wei Xu, Rui Zhang, Guoqiu Wu, and Xiaobo Fan
- Subjects
Pulmonary Fibrosis ,medicine.medical_treatment ,Connective tissue ,Peptide binding ,02 engineering and technology ,Bleomycin ,Biochemistry ,03 medical and health sciences ,chemistry.chemical_compound ,Protein Domains ,Peptide Library ,Structural Biology ,In vivo ,Fibrosis ,Pulmonary fibrosis ,medicine ,Humans ,Molecular Biology ,030304 developmental biology ,0303 health sciences ,integumentary system ,Growth factor ,Connective Tissue Growth Factor ,General Medicine ,021001 nanoscience & nanotechnology ,medicine.disease ,Molecular biology ,CTGF ,medicine.anatomical_structure ,chemistry ,Peptides ,0210 nano-technology ,Protein Binding - Abstract
Using phage display technology, 810A was developed as a novel peptide, which binds to the C-terminal domain of connective tissue growth factor (CTGF). The present study investigated whether this peptide could neutralize CTGF and block its biological activity as a specific strategy to treat pulmonary fibrosis in vitro and in vivo. Human bronchial epithelial (16HBE) cells were treated with CTGF to evaluate the anti-CTGF capability of 810A using MTT testing, cell migration assays, and Western blotting. The action of 810A in mouse models of bleomycin (BLM)-induced pulmonary fibrosis was evaluated according to leukocyte counts in bronchoalveolar lavage fluid (BALF), hydroxyproline content, and pathological analysis. Treatment with 810A resulted in inhibition of cell proliferation, migration, and increases in transforming growth factor-beta (TGF-β) and α-Smooth muscle actin (α-SMA) caused by CTGF treatment in vitro. In vivo, 810A significantly alleviated fibrosis in the pulmonary index. Inflammation was inhibited, as inferred by the reduced number of leukocytes in BALF. Pathophysiological analysis indicated that hydroxyproline content, alveolar enlargement, interstitial inflammatory infiltration, and collagen deposition were reduced. Collectively, these data suggest that 810A may potentially be a CTGF-specific, small-molecule antagonist, providing a new method for prevention and treatment of pulmonary fibrosis.
- Published
- 2020
3. Dissipative dual-wavelength pulses synchronously mode-locked in a compact fiber laser
- Author
-
Liqiang Zhang, Yicun Yao, Xiaohui Li, Nan-Kuang Chen, Chenglin Bai, Fan Yang, Zhen Tian, Yingying Ren, and Minghong Wang
- Subjects
Electrical and Electronic Engineering ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials - Published
- 2022
4. Precisely fabricating Ce-O-Ti structure to enhance performance of Ce-Ti based catalysts for selective catalytic reduction of NO with NH3
- Author
-
Zhaoyang Fei, Xian Chen, Minghong Wang, Qing Liu, Zuliang Tao, Jihai Tang, Cui Mifen, Xu Qiao, Yanran Yang, and Zhuxiu Zhang
- Subjects
inorganic chemicals ,Materials science ,General Chemical Engineering ,Selective catalytic reduction ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Redox ,Industrial and Manufacturing Engineering ,0104 chemical sciences ,Catalysis ,Reaction rate ,symbols.namesake ,Adsorption ,Chemical engineering ,X-ray photoelectron spectroscopy ,symbols ,Environmental Chemistry ,Fourier transform infrared spectroscopy ,0210 nano-technology ,Raman spectroscopy - Abstract
A series of Ce-Ti mixed oxides (CeaTi1−a) were successfully synthesized by a spontaneous deposition method and evaluated in selective catalytic reduction of NO with NH3 (NH3-SCR). The structures and properties of the CeaTi1−a catalysts were characterized by means of XRD, Raman, TEM, N2-sorption, XPS, H2-TPR and NH3-TPD. The results demonstrated that lots of Ce-O-Ti species were formed because of the strong synergistic interaction of gelation of TiO2 and deposition of Ce3+ during the preparation process of CeaTi1−a catalysts. As results, the CeaTi1−a catalysts exhibited excellent redox ability, enrichment of Ce3+ species, high surface adsorbed oxygen concentration, and abundant acid sites. The CeaTi1−a catalysts showed remarkable catalytic activity with broad operation temperature window, and Ce0.5Ti0.5 catalyst exhibited the best catalytic activity and extraordinary H2O/SO2 durability. The in-situ FTIR results revealed that the mechanisms of L-H and E-R existed synchronously during the NH3-SCR reaction, and the former one was predominant due to its rapid reaction rate.
- Published
- 2018
5. Roles of graphene nanogap for the AgNFs electrodeposition on the woven Cu net as flexible substrate and its application in SERS
- Author
-
Wenyuan Zhang, Ying Shi, Peihong Man, Minghong Wang, Yuanyuan Xu, Cheng Yang, Baoyuan Man, and Zhen Li
- Subjects
Materials science ,Graphene ,chemistry.chemical_element ,Marine fish ,Nanotechnology ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Copper ,0104 chemical sciences ,law.invention ,Rhodamine 6G ,Metal ,chemistry.chemical_compound ,chemistry ,law ,visual_art ,Homogeneity (physics) ,visual_art.visual_art_medium ,General Materials Science ,Crystal violet ,0210 nano-technology ,Close contact - Abstract
A new substrate composing of Ag nanoflowers on graphene@Cu net (AgNFs/G@Cu) was fabricated on the flexible woven copper net. Graphene, an ideal 2D plane, provides better dispersion of regular electrodeposited AgNFs arrays. Graphene nanogap was used to enhance the EM coupling between AgNFs and metal Cu substrate. Regular AgNFs arrays offer denser “hotspots”, which further enhance the EM coupling. High sensitivity (rhodamine 6G (R6G): 10−14 M, crystal violet (CV): 10−12 M) and good homogeneity are realized in our experiment and proved by the COMSOL simulation. Cu net, remarkable flexibility and practicality, allows for a close contact to the sample surface by swabbing. Malachite green (MG) as low as 10−11 M on the surface of the marine fish can be detected. This work may offer novel and practical SERS applications in the areas of pesticide residue, food security and biotechnology.
- Published
- 2018
6. A novel natural surface-enhanced Raman spectroscopy (SERS) substrate based on graphene oxide-Ag nanoparticles-Mytilus coruscus hybrid system
- Author
-
Baoyuan Man, Minghong Wang, Shouzhen Jiang, Zhengyi Lu, Yanyan Huo, Chao Zhang, Zhe Li, Shicai Xu, Zhen Li, and Yan Jun Liu
- Subjects
Materials science ,Resonance Raman spectroscopy ,Oxide ,Nanotechnology ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,law.invention ,Rhodamine 6G ,chemistry.chemical_compound ,symbols.namesake ,law ,Materials Chemistry ,Electrical and Electronic Engineering ,Instrumentation ,biology ,Graphene ,Metals and Alloys ,Natural surface ,Substrate (chemistry) ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,biology.organism_classification ,0104 chemical sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,chemistry ,Mytilus coruscus ,symbols ,0210 nano-technology ,Raman spectroscopy - Abstract
Recently, biological materials have attracted more and more attentions on preparing the surface-enhanced Raman spectroscopy (SERS) substrate with the conspicuous SERS performance. Herein, we demonstrate a simply facile and inexpensive approach to fabricate a novel natural SERS substrate based on graphene oxide-Ag nanoparticles-Mytilus coruscus (GO-AgNPs-M.c.). The surface-enhanced resonance Raman spectroscopy (SERRS) signals of the Rhodamine 6G (R6G) on the GO-AgNPs-M.c. hybrids exhibit the much better SERRS performances in terms of the sensitivity, the signal reproducibility and the antioxidant stability than that on the AgNPs-M.c. one. The well electric field enhancement contribution is likewise confirmed in theory via the COMSOL software. Moreover, the successful detection of trace malachite green (MG) and methylene blue (MB) indicates the well feasibility for multi-molecules detection on the GO-AgNPs-M.c. hybrids. Thus, this inexpensive and high-efficiency natural SERS substrate have great potential for the considerable biochemical SERS applications and broaden the way for preparing multiple SERS platforms derived from other natural materials.
- Published
- 2018
7. Different number of silver nanoparticles layers for surface enhanced raman spectroscopy analysis
- Author
-
Minghong Wang, Chonghui Li, Shuyun Wang, Yang Jiao, Zhen Li, Aihua Liu, Yuanyuan Xu, Baoyuan Man, Cheng Yang, and Chao Zhang
- Subjects
inorganic chemicals ,Fabrication ,Materials science ,Nanotechnology ,Ag nanoparticles ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,Silver nanoparticle ,law.invention ,symbols.namesake ,law ,Materials Chemistry ,Electrical and Electronic Engineering ,Penetration depth ,Instrumentation ,health care economics and organizations ,technology, industry, and agriculture ,Metals and Alloys ,Substrate (chemistry) ,Surface-enhanced Raman spectroscopy ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Laser ,0104 chemical sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,symbols ,0210 nano-technology ,Raman spectroscopy - Abstract
For application in practice, reducing the cost and simplifying the steps in fabrication of SERS substrates with excellent property are still the important factors. Here, a three-dimensional (3D) Ag nanoparticles (NPs) obtained by facile thermal evaporation is obtained for SERS. The Raman enhancement effect gradually become strong as the number of Ag NPs layers increase and attain the best until four layers Ag NPs deposited for the finite penetration depth of incident laser. The intensity of Raman signal collected from the four-layer Ag NPs substrate is around 11.3 times stronger than that from one-layer Ag NPs. Besides, the reproducibility of the SERS substrate was also significantly promoted as the layers of Ag NPs increases. The SERS substrate exhibits temporal stability and its enhancement factor attains 6.8 × 108. Furthermore, the SERS substrate can easily combine with some other blocks with superior SERS property and show better SERS ability. Additionally, the in-situ trace analyses in aquatic products were realized by flexible Ag NPs/PET substrate.
- Published
- 2018
8. Three-dimensional nanoporous MoS2 framework decorated with Au nanoparticles for surface-enhanced Raman scattering
- Author
-
Aihua Liu, Baoyuan Man, Mei Liu, Yingqiang Sheng, Zhen Li, Minghong Wang, Cheng Yang, Yanyan Huo, Shouzhen Jiang, and Chao Zhang
- Subjects
Materials science ,Nanoporous ,General Physics and Astronomy ,Nanoparticle ,Nanotechnology ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Rhodamine 6G ,chemistry.chemical_compound ,symbols.namesake ,chemistry ,Electric field ,symbols ,Molecule ,Physical and Theoretical Chemistry ,Selected area diffraction ,0210 nano-technology ,Raman spectroscopy ,Raman scattering - Abstract
The three-dimensional (3D) MoS 2 decorated with Au nanoparticles (Au NPs) hybrids (3D MoS 2 -Au NPs) for surface-enhanced Raman scattering (SERS) sensing was demonstrated in this paper. SEM, Raman spectroscopy, TEM, SAED, EDX and XRD were performed to characterize 3D MoS 2 -Au NPs hybrids. Rhodamine 6G (R6G), fluorescein and gallic acid molecules were used as the probe for the SERS detection of the 3D MoS 2 -Au NPs hybrids. In addition, we modeled the enhancement of the electric field of MoS 2 -Au NPs hybrids using Finite-difference time-domain (FDTD) analysis, which can further give assistance to the mechanism understanding of the SERS activity.
- Published
- 2017
9. The use of the constant vector basis functions for the magnetic field integral equation
- Author
-
Liming Zhang, Ali Deng, and Minghong Wang
- Subjects
Applied Mathematics ,Mathematical analysis ,Linear system ,General Engineering ,Basis function ,Function (mathematics) ,Solver ,Method of moments (statistics) ,Impedance parameters ,Computational Mathematics ,Iterated function ,Constant (mathematics) ,Analysis ,Mathematics - Abstract
The magnetic field integral equation (MFIE) is widely used in the analysis of electromagnetic scattering problems for conducting objects. Usually, the MFIE is solved by the method of moments (MoM) using the Rao–Wilton–Glisson (RWG) basis functions. In this paper, a new kind of basis function which is named the piece-wise constant vector basis function is proposed and used to solve the MFIE by MoM. Definition of this kind of basis function is given. The calculation of the impedance matrix entries is presented in detail. This kind of basis function is then used for the solution of the MFIE for electromagnetic scattering problems. The radar cross section (RCS) results and the iterative property of both kinds of basis functions are presented. It is shown that the piece-wise constant vector basis functions give similar RCS results as those of the RWG basis functions. Particularly, when iterative solver is used to solve the resultant linear system, the solution scheme using the piece-wise constant vector basis functions iterates much faster than that using the RWG basis functions.
- Published
- 2015
10. Passively Q-switched mode-locked dual-wavelength Nd:GYSGG laser using graphene oxide saturable absorber
- Author
-
Qi Song, Guoju Wang, Qingli Zhang, Minghong Wang, Bingyuan Zhang, Wenjun Wang, Yong Bo, Guihua Sun, and Qinjun Peng
- Subjects
Materials science ,business.industry ,Graphene ,Energy conversion efficiency ,Oxide ,Saturable absorption ,Laser ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,law.invention ,chemistry.chemical_compound ,Wavelength ,Optics ,chemistry ,law ,Electrical and Electronic Engineering ,Physical and Theoretical Chemistry ,business ,Pulse-width modulation ,Envelope (waves) - Abstract
Passively Q-switched mode-locked dual-wavelength Nd:GYSGG laser using graphene oxide saturable absorber is demonstrated. The output spectrum peaked at 1057.28 nm and 1060.23 nm with wavelength spacing of 3 nm has been measured. At the pump power of 5 W, the maximum average output power of 0.189 W was obtained with the optical conversion efficiency of 3.79%. The mode-locked pulse inside the Q-switched envelope has a repetition rate of 100 MHz and its pulse width is estimated to be about 441 ps. In addition, a simple way to fabricate few layers graphene oxide saturable absorbers has been reported.
- Published
- 2015
11. Memristive behavior and forming mechanism of homogeneous TiOx device
- Author
-
Zhang Zhang, Xunling Yan, Minghong Wang, and Ruixin Dong
- Subjects
Materials science ,business.industry ,Mechanical Engineering ,Oxide ,Nanotechnology ,Memristor ,Condensed Matter Physics ,law.invention ,Titanium oxide ,chemistry.chemical_compound ,chemistry ,Mechanics of Materials ,law ,Electrical resistivity and conductivity ,Electrode ,Optoelectronics ,General Materials Science ,Electric potential ,business ,Molecular beam epitaxy ,Voltage - Abstract
A homogeneous titanium oxide device is fabricated by Molecular Beam Epitaxy and the excellent memristive behavior could be observed. The resistance ratio between high resistance state and low resistance state increases as the thickness of titanium oxide or the oxygen content reduces. The forming voltage is lower than the previous report. Based on the experimental results, we suggest a double-interface conductive filament model and calculate the current–voltage curve of the device in agreement with experimental measurements. The result indicates that the forming voltage of the device will rise with increasing of the chemical potential differences across the two interfaces. In other words, the switching voltage could be adjusted by selecting a proper electrode and oxide materials.
- Published
- 2015
12. Passively Q-switched Nd:YVO4 laser using molybdenum disulfide (MoS2) as a saturable absorber
- Author
-
Guoju Wang, null Qi.Song, Bingyuan Zhang, Yajing Gao, Wenjun Wang, and Minghong Wang
- Subjects
Materials science ,Manufacturing process ,business.industry ,Saturable absorption ,02 engineering and technology ,Substrate (electronics) ,021001 nanoscience & nanotechnology ,Laser ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,law.invention ,010309 optics ,chemistry.chemical_compound ,Optics ,chemistry ,law ,0103 physical sciences ,Optoelectronics ,Electrical and Electronic Engineering ,0210 nano-technology ,business ,Laser pulse width ,Absorption (electromagnetic radiation) ,Molybdenum disulfide - Abstract
We demonstrate the use of molybdenum disulfide (MoS2)-based saturable absorber to develop a passively Q-switched Nd:YVO4 laser. The few-layer MoS2 saturable absorber was prepared by mixing MoS2 with alcohol and then evaporating the mixture on a substrate. Using an MoS2 saturable absorber, stable Q-switching operation was achieved with a laser pulse width of 327 ns and a repetition rate of 5 kHz under a pump power of 2.23 W. Due to the simple manufacturing process and high saturated absorption characteristics, MoS2 seems to be a suitable material as a saturable absorber for solid-state lasers.
- Published
- 2016
13. Transmission performance of 1 × 2 type photonic crystal power splitter with ring resonators
- Author
-
Liheng Wu and Minghong Wang
- Subjects
Physics ,business.industry ,Finite-difference time-domain method ,Physics::Optics ,Electromagnetic radiation ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,Power (physics) ,Resonator ,Wavelength ,Optics ,Splitter ,Electrical and Electronic Engineering ,business ,Passband ,Photonic crystal - Abstract
The structure of 1 × 2 type photonic crystal power splitter with ring resonators is designed in a two-dimension square-lattice dielectric-rod photonic crystal structure, and it consists of one input and two outputs. Its transmission performance is investigated by using the finite-difference time-domain (FDTD) method. The results show that the structure has high transmission efficiency in the third communication window (wavelength 1550 nm), can split pass band electromagnetic waves equally. It is compact with low loss and design flexibility in propagation direction of electromagnetic waves.
- Published
- 2015
14. An efficient method for electromagnetic scattering analysis
- Author
-
Minghong Wang, Ali Deng, and Liming Zhang
- Subjects
Radar cross-section ,Discretization ,Scattering ,Applied Mathematics ,Mathematical analysis ,General Engineering ,Basis function ,Function (mathematics) ,Method of moments (statistics) ,Computational Mathematics ,Magnetic field integral equations ,Linear combination ,Analysis ,Mathematics - Abstract
We present a novel method to solve the magnetic field integral equation (MFIE) using the method of moments (MoM) efficiently. This method employs a linear combination of the divergence-conforming Rao–Wilton–Glisson (RWG) function and the curl-conforming n × RWG function to test the MFIE in MoM. The discretization process and the relationship of this new testing function with the previously employed RWG and n × RWG testing functions are presented. Numerical results of radar cross section (RCS) data for objects with sharp edges and corners show that accuracy of the MFIE can be improved significantly through the use of the new testing functions. At the same time, only the commonly used RWG basis functions are needed for this method.
- Published
- 2012
15. Study of the monopolar RWG and monopolar n×RWG basis functions for electromagnetic scattering analysis
- Author
-
Liming Zhang, Ali Deng, and Minghong Wang
- Subjects
Scattering cross-section ,Scattering ,Applied Mathematics ,Mathematical analysis ,General Engineering ,Basis function ,Geometry ,Impedance parameters ,Integral equation ,Computational Mathematics ,Singularity ,Magnetic field integral equations ,Divergence (statistics) ,Analysis ,Mathematics - Abstract
In this paper, we study the accuracy and the efficiency of the monopolar divergence-conforming Rao–Wilton–Glisson (RWG) and the monopolar curl-conforming n×RWG basis functions for the magnetic field integral equation (MFIE). Similar to cases using RWG and n×RWG basis functions for the MFIE, there are two impedance matrix elements calculation schemes if the monopolar RWG and monopolar n×RWG basis functions are used to the MFIE, respectively. The monopolar basis functions and the implementation schemes used for the MFIE are discussed. The scattering cross section data as well as the CPU time needed to fill the corresponding impedance matrix obtained from numerical solutions of these implementation schemes using monopolar basis functions are investigated. For the monopolar basis functions and the implementation schemes considered, the first scheme of the MFIE using the monopolar curl-conforming n×RWG basis functions gives most accurate results and it is the best choice for the use of the monopolar basis functions to the MFIE.
- Published
- 2011
16. Investigation of two formulations using curl-conforming basis functions for the MFIE
- Author
-
Minghong Wang, Shaoqing Yang, Ali Deng, and Liming Zhang
- Subjects
Curl (mathematics) ,Radar cross-section ,Scattering ,Applied Mathematics ,General Engineering ,Basis function ,Impedance parameters ,Integral equation ,Electromagnetic radiation ,Computational Mathematics ,Calculus ,Applied mathematics ,Analysis ,Matrix method ,Mathematics - Abstract
The magnetic field integral equation (MFIE) is widely used in method of moments (MoM) for electromagnetic scattering analysis of arbitrarily shaped three-dimensional conducting objects. Besides the well-known Rao–Wilton–Glisson (RWG) basis functions, the curl-conforming n×RWG basis functions are also used in MFIE to improve its accuracy. However, there are two different impedance matrix element formulations that result from the use of the n×RWG basis and testing functions to the MFIE in the literature. Moreover, one of the formulations is more complicated than the other. This stimulates us to explore which formulation is more efficient in improving the accuracy of the MFIE. This paper investigates the efficiency of two impedance matrix element formulations resulting from the use of the curl-conforming n×RWG basis and testing functions to the MFIE. Details to calculate the impedance matrix elements are studied. Numerical results show that the radar cross section (RCS) results of the first formulation are more accurate than those of the second one while consuming only about half of the time to fill the impedance matrix for the second formulation. Thus, compared with the second formulation, the first formulation resulting from the use of the curl-conforming n×RWG basis functions to the MFIE is a better choice for scattering analysis of three-dimensional conducting objects.
- Published
- 2011
17. Application of the combined RWG basis functions to the MFIE for the scattering analysis of small sharp-edged objects
- Author
-
Minghong Wang, Ali Deng, and Liming Zhang
- Subjects
Discretization ,Basis (linear algebra) ,Scattering ,Applied Mathematics ,Minor (linear algebra) ,Mathematical analysis ,General Engineering ,Basis function ,Context (language use) ,Method of moments (statistics) ,Integral equation ,Computational Mathematics ,Analysis ,Mathematics - Abstract
We present a novel implementation of the magnetic field integral equation (MFIE) with the use of the combined Rao–Wilton–Glisson (RWG) basis and testing functions. Implementation details are outlined in the context of the method of moments. For a wide variety of small sharp-edged objects, we show that accuracy of the MFIE can be greatly improved with a combination parameter of about 0.2 for the combined RWG functions. This is achieved with relatively coarse discretization for the scatterers and with only minor modifications in the existing codes based on the RWG and n×RWG functions.
- Published
- 2010
18. Numerical study of a novel MFIE formulation using monopolar RWG basis functions
- Author
-
Shaoqing Yang, Minghong Wang, Liming Zhang, and Ali Deng
- Subjects
Radar cross-section ,Basis (linear algebra) ,Hardware and Architecture ,Mathematical analysis ,General Physics and Astronomy ,Magnetic field integral equations ,Basis function ,Method of moments (statistics) ,Impedance parameters ,Mathematics - Abstract
Numerical character of a new magnetic field integral equation (MFIE) formulation solved by the method of moments (MoM) is studied. In this new formulation, monopolar Rao–Wilton–Glisson (RWG) functions are used as both the basis and the testing functions. Calculation details for the impedance matrix elements of this new formulation are presented with a form suitable for programming. Numerical results for electromagnetic scattering analysis of several small sharp-edged conducting objects show that the new formulation using the monopolar RWG basis functions is much more accurate than the traditional one using the RWG and the monopolar RWG basis functions.
- Published
- 2010
19. Application of an accurate approach to calculate the almost singular double surface integrals of the MFIE
- Author
-
Ali Deng, Liming Zhang, and Minghong Wang
- Subjects
Iterative method ,Applied Mathematics ,Mathematical analysis ,Surface integral ,General Engineering ,Basis function ,Method of moments (statistics) ,Electric-field integral equation ,Computer Graphics and Computer-Aided Design ,Integral equation ,Finite element method ,Singularity ,Analysis ,Mathematics - Abstract
Accurate calculation of the almost singular double surface integrals is essential for successful solutions of the magnetic field integral equation (MFIE) by method of moments (MoM) using Rao-Wilton-Glisson (RWG) basis functions, especially for the scattering analysis of small conducting objects. In this paper, an accurate singularity extraction technique to avoid logarithmic singularity of the integration on the testing triangles is used for the MFIE. The numerical examples of several small sharp-edged conducting objects demonstrate that accuracy of the MFIE is improved with the use of the new technique. In addition, the MFIE converges much faster than the electric field integral equation (EFIE) when iterative equation solvers are employed, which means high efficiency and a suitable choice for very low frequency small sharp-edged conducting object problems using this new singularity extraction technique.
- Published
- 2009
20. Using an accurate singularity extraction technique to the MFIE for the scattering analysis of small objects
- Author
-
Minghong Wang, Ali Deng, and Liming Zhang
- Subjects
Logarithm ,Scattering ,Applied Mathematics ,Mathematical analysis ,Surface integral ,General Engineering ,Domain decomposition methods ,Basis function ,Method of moments (statistics) ,Integral equation ,Computational Mathematics ,Singularity ,Analysis ,Mathematics - Abstract
The method of moments (MoM) solution on the magnetic field integral equation (MFIE) for electromagnetic scattering problems of conducting objects with Rao–Wilton–Glisson (RWG) basis functions requires the evaluation of almost singular double surface integrals over triangular subdomains. Calculating these integrals accurately is essential for the successful solution of the MFIE by MoM especially for small sharp-edged conducting objects. This paper studies the singularity of the MFIE and uses an accurate singularity extraction technique to avoid logarithmic singularity of the integration on the testing triangles for the MFIE. Based on the numerical examples of several small sharp-edged conducting objects, it is demonstrated that the accuracy of the MFIE is improved greatly with the use of the new singularity extraction technique.
- Published
- 2009
21. Study on a novel Smith–Purcell free-electron laser
- Author
-
Xiaoguang Xiao, Minghong Wang, Yanyu Wei, and Jiayu Chen
- Subjects
Physics ,business.industry ,Free-electron laser ,General Physics and Astronomy ,Electron ,Laser ,Electromagnetic radiation ,law.invention ,Wavelength ,Smith–Purcell effect ,chemistry.chemical_compound ,Resonator ,Optics ,chemistry ,law ,Millimeter ,business - Abstract
A novel Smith–Purcell (SP) free-electron laser (FEL) with axial-symmetrical structure is proposed. The distribution of the high frequency field in the resonator is analyzed and the operating frequency and output power are also studied by the use of particle-in-cell (PIC) simulation method. Results indicate that coherent radiation with output peak power up to 58 MW at millimeter wavelengths can be generated by using relativistic electron beams of moderate energy.
- Published
- 2005
22. Study on the high frequency structure of FEM amplifier
- Author
-
Xiaoguang Xiao, Zheng Liang, and Minghong Wang
- Subjects
Physics ,business.industry ,Amplifier ,Wiggler ,General Physics and Astronomy ,Finite element method ,law.invention ,Optics ,Planar ,Computer Science::Sound ,law ,Magnet ,Cathode ray ,business ,Waveguide ,Voltage - Abstract
The compact free electron maser (FEM), with the advantages of small size and low cost, is important for realistic applications in medicine and industry. In order to utilize the planar wiggler to the best advantage and simultaneously to reduce the necessary electron beam voltage and the size of FEM device, we propose to utilize an elliptical waveguide as the high frequency structure of planar wiggler FEM. A set of universal operating equations suitable for elliptical waveguide and rectangular waveguide FEMs is derived by using the nonlinear theory. The characteristics of the FEMs are numerically analyzed, comparatively.
- Published
- 2005
23. Spatiotemporal properties of the fetal magnetocardiogram
- Author
-
Minghong Wang, Ronald T. Wakai, and Chester B. Martin
- Subjects
Fetus ,Time Factors ,Cardiac cycle ,medicine.diagnostic_test ,business.industry ,Obstetrics and Gynecology ,Fetal heart ,Anatomy ,Heart Rate, Fetal ,Fetal monitoring ,Electrocardiography ,Magnetics ,QRS complex ,Nuclear magnetic resonance ,Pregnancy ,Heart Function Tests ,Humans ,Medicine ,Female ,Fetal Monitoring ,business ,Magnetocardiography ,Ventricular depolarization - Abstract
OBJECTIVE: Our purpose was to investigate the spatiotemporal properties of the fetal magnetocardiogram. STUDY DESIGN: Fetal magnetocardiogram maps were measured for the first time in 20 subjects from 22 to 39 weeks' gestation. Waveform and topographic maps were used to display the data. RESULTS: The maps showed spatiotemporal properties consistent with simple volume conductor theory: topography was closely related to the presentation of the fetus, Q-wave sources were dipolar and localized, the magnetic heart vector rotated extensively during the QRS complex, and close correspondence was observed between fetal and neonatal maps. Ventricular depolarization and events in the cardiac cycle could be visualized in considerable detail by means of a time series of topographic maps. CONCLUSION: Fetal magnetocardiogram shows excellent spatiotemporal properties and is well suited for in utero studies of fetal heart activity. (AM J OBSTET GYNECOL 1994;170:770-6.)
- Published
- 1994
24. Spectral analysis of antepartum fetal heart rate variability from fetal magnetocardiogram recordings
- Author
-
Stephen L. Pedron, Minghong Wang, Chester B. Martin, Ronald T. Wakai, and Deborah L. Reid
- Subjects
Adult ,Pregnancy ,Fetus ,Fetal Heart Rate Variability ,business.industry ,Obstetrics and Gynecology ,Gestational Age ,Heart Rate, Fetal ,medicine.disease ,Magnetics ,Anesthesia ,Heart Function Tests ,Pediatrics, Perinatology and Child Health ,Heart rate ,medicine ,Humans ,Gestation ,Heart rate variability ,Female ,Vagal tone ,Fetal Monitoring ,business ,Magnetocardiography - Abstract
Fetal heart rate variability was derived from fetal magnetocardiogram recordings in ten subjects at gestation ages 32–38 weeks. Maternal interference was negligible and R-wave detection was highly reliable. Oscillations suggestive of respiratory sinus arrhythmia (RSA) were prominent in many of the heart rate tracings. Spectral analysis was used to quantify heart rate variability and to examine the influence of the RSA-like oscillations on heart rate variability. The oscillations were associated with increased power in the frequency range 0.4–1.0 Hz (P ≤ 0.05). Magnetic recording appears to offer significant advantages for investigation of beat-to-beat fetal heart rate throughout the latter stages of pregnancy.
- Published
- 1993
25. HL-2A control system and its discharge management
- Author
-
Xianming, Song, primary, Chao, Jiang, additional, Qiang, Li, additional, Bo, Li, additional, Mingjie, Fan, additional, Liaoyuan, Chen, additional, Cuiwen, Luo, additional, Minghong, Wang, additional, Fangqun, Tang, additional, Li, Liu, additional, Suying, Mao, additional, and Feidi, Li, additional
- Published
- 2003
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.