A trinudear Mn（II） coordination complex Mna （HEDTA）2-10H20 （EDTA=ethylene diamine tetraacetic acid） 1 has been synthesized and characterized by X-ray crystal structure determination. In addition, IR spectrum, th...A trinudear Mn（II） coordination complex Mna （HEDTA）2-10H20 （EDTA=ethylene diamine tetraacetic acid） 1 has been synthesized and characterized by X-ray crystal structure determination. In addition, IR spectrum, thermogravimetric analysis, electron paramagnetic resonance （EPR） spectra and magnetic susceptibility of this complex are discussed. X-ray determination indicates that six- and seven-coordinate modes between Mn（Yl） and H4EDTA exist alternately in 1. Furthermore, detailed discussion of magnetic ordering in tile temperature range of 2-300 K reveals the antiferromagnetic interactions in the complex.展开更多
A three-layer waveguide structure sensor consists of LHMs （left-handed materials） film surrounded by dielectric cladding and antiferromagnetie substrate is proposed. LHMs known as MTMs （metamaterials） have simulta...A three-layer waveguide structure sensor consists of LHMs （left-handed materials） film surrounded by dielectric cladding and antiferromagnetie substrate is proposed. LHMs known as MTMs （metamaterials） have simultaneous negative permeability and permittivity. The dispersion relation for the structure is derived for TE guided modes. Two ranges of frequencies are chosen such that Voigt permeability,μv, either negative or positive. The sensitivity is proven to be affected by different parameters including the film thickness, LHM parameters, and Voigt frequency.展开更多
We studied the biological effects of different magnetic fields. Identified bacterial strain Escherichia coli （type I） has been exposed to the dipolar magnetic field force （400, 800, 1200 and 1600 Gausses） which pr...We studied the biological effects of different magnetic fields. Identified bacterial strain Escherichia coli （type I） has been exposed to the dipolar magnetic field force （400, 800, 1200 and 1600 Gausses） which prepared locally with incubation for different period times （24, 48 and 72 hrs） at 37℃. The effects were evaluated by optical density （OD） at 600 nm determining their growth density incorporation with negative control and depending of McFarland turbidity standard （0.5）, in addition to its susceptibility to various antibiotics. Results illustrate different forces of magnetic field decreased the growth rate of E. coli in particular at 24 hrs incubation comparing with unexposed or control samples. The magnetic field increased the logarithmic phase within 4-6 hrs of treatment but decreased after 16 to 18 hrs. Furthermore, changes in the antibiotic sensitivity were observed after exposure period of 6 hrs since E. coli cells became more sensitive to certain antibiotics. While after a 16 hrs exposure period, it became more resistant to the same antibiotics comparing with control groups.展开更多
An all fiber magnetic field sensor with peanut-shape structure based on multimode fiber(MMF) is proposed and experimentally demonstrated. The sensing structure and magnetic fluid(MF) are both encapsulated in capillary...An all fiber magnetic field sensor with peanut-shape structure based on multimode fiber(MMF) is proposed and experimentally demonstrated. The sensing structure and magnetic fluid(MF) are both encapsulated in capillary, and the effective refractive index of MF is affected by surrounding magnetic field strength. The measurement of magnetic field is realized by observing the wavelength drift of interference peak. The transmission spectrum generated by Mach-Zehnder interferometer(MZI) includes core-core mode interference and core-cladding mode interference. Experimental results demonstrate that the core-cladding mode interference is sensitive to magnetic field, and the magnetic field sensitivity is 0.047 8 nm/mT. In addition, two kinds of interference dips are sensitive to temperature, and the sensitivities are 0.060 0 nm/°C and 0.052 6 nm/°C, respectively. So the simultaneous measurement of magnetic field strength and temperature can be achieved based on sensitivity matrix.展开更多
This article describes in detail a technique for model!ng cavity optomechanical field sensors. A magnetic or electric field induces a spatially varying stress across the sensor, which then induces a force on mechanica...This article describes in detail a technique for model!ng cavity optomechanical field sensors. A magnetic or electric field induces a spatially varying stress across the sensor, which then induces a force on mechanical eigenmodes of the system. The force on each oscillator can then be determined from an overlap integral between magnetostrictive stress and the corresponding eigenmode, with the optomechanical coupling strength determining the ultimate resolution with which this force can be detected. Furthermore, an optomechanical magnetic field sensor is compared to other magnetic field sensors in terms of sensitivity and potential for miniaturization. It is shown that an optomechanical sensor can potentially outperform state-of-the-art magnetometers of similar size, in particular other sensors based on a magnetostrictive mechanism.展开更多
That whether unidirectional tension changes the influence of incident angle on FSS's(frequency selective surface) electromagnetic(EM) property and whether incident angle changes the effect of unidirectional intens...That whether unidirectional tension changes the influence of incident angle on FSS's(frequency selective surface) electromagnetic(EM) property and whether incident angle changes the effect of unidirectional intension on FSS's EM property is researched.The pattern and magnitude of these changes are revealed.Firstly,the analyses for the mechanism of unidirectional tension's influence and the mechanism of the coupling between the influences of unidirectional tension and incident angle are conducted.Then,according to the mechanism of these influences,Mechanics-Electromagnetics co-analysis is conducted based on mechanics finite element method and electromagnetics finite element method.The frequency responses of the FSS which is under different unidirectional tensions and illuminated by EM wave incident at different angles are gained.The concept"unidirectional tensile sensitivity of FSS"is put forward along with two unidirectional tensile sensitivity factors.By using angular sensitivity-factor and unidirectional tensile sensitivity-factor,the influences of unidirectional tension and incident angle,which are coupled with each other,are expatiated respectively.Research results show that these influences have two sides.Meanwhile,basing on Mode Matching Method and according to the results of numerical investigation,one principle for the layout of FSS with apertures is gained.Several suggestions for further research are given.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.20490210,10574047)the Doctor Foundation of China(Grant No.20030487003)
文摘A trinudear Mn（II） coordination complex Mna （HEDTA）2-10H20 （EDTA=ethylene diamine tetraacetic acid） 1 has been synthesized and characterized by X-ray crystal structure determination. In addition, IR spectrum, thermogravimetric analysis, electron paramagnetic resonance （EPR） spectra and magnetic susceptibility of this complex are discussed. X-ray determination indicates that six- and seven-coordinate modes between Mn（Yl） and H4EDTA exist alternately in 1. Furthermore, detailed discussion of magnetic ordering in tile temperature range of 2-300 K reveals the antiferromagnetic interactions in the complex.
文摘A three-layer waveguide structure sensor consists of LHMs （left-handed materials） film surrounded by dielectric cladding and antiferromagnetie substrate is proposed. LHMs known as MTMs （metamaterials） have simultaneous negative permeability and permittivity. The dispersion relation for the structure is derived for TE guided modes. Two ranges of frequencies are chosen such that Voigt permeability,μv, either negative or positive. The sensitivity is proven to be affected by different parameters including the film thickness, LHM parameters, and Voigt frequency.
文摘We studied the biological effects of different magnetic fields. Identified bacterial strain Escherichia coli （type I） has been exposed to the dipolar magnetic field force （400, 800, 1200 and 1600 Gausses） which prepared locally with incubation for different period times （24, 48 and 72 hrs） at 37℃. The effects were evaluated by optical density （OD） at 600 nm determining their growth density incorporation with negative control and depending of McFarland turbidity standard （0.5）, in addition to its susceptibility to various antibiotics. Results illustrate different forces of magnetic field decreased the growth rate of E. coli in particular at 24 hrs incubation comparing with unexposed or control samples. The magnetic field increased the logarithmic phase within 4-6 hrs of treatment but decreased after 16 to 18 hrs. Furthermore, changes in the antibiotic sensitivity were observed after exposure period of 6 hrs since E. coli cells became more sensitive to certain antibiotics. While after a 16 hrs exposure period, it became more resistant to the same antibiotics comparing with control groups.
基金supported by the National High Technology Research and Development Program of China(No.2013AA014200)the National Natural Science Foundation of China(No.11444001)the Municipal Natural Science Foundation of Tianjin(No.14JCYBJC16500)
文摘An all fiber magnetic field sensor with peanut-shape structure based on multimode fiber(MMF) is proposed and experimentally demonstrated. The sensing structure and magnetic fluid(MF) are both encapsulated in capillary, and the effective refractive index of MF is affected by surrounding magnetic field strength. The measurement of magnetic field is realized by observing the wavelength drift of interference peak. The transmission spectrum generated by Mach-Zehnder interferometer(MZI) includes core-core mode interference and core-cladding mode interference. Experimental results demonstrate that the core-cladding mode interference is sensitive to magnetic field, and the magnetic field sensitivity is 0.047 8 nm/mT. In addition, two kinds of interference dips are sensitive to temperature, and the sensitivities are 0.060 0 nm/°C and 0.052 6 nm/°C, respectively. So the simultaneous measurement of magnetic field strength and temperature can be achieved based on sensitivity matrix.
文摘This article describes in detail a technique for model!ng cavity optomechanical field sensors. A magnetic or electric field induces a spatially varying stress across the sensor, which then induces a force on mechanical eigenmodes of the system. The force on each oscillator can then be determined from an overlap integral between magnetostrictive stress and the corresponding eigenmode, with the optomechanical coupling strength determining the ultimate resolution with which this force can be detected. Furthermore, an optomechanical magnetic field sensor is compared to other magnetic field sensors in terms of sensitivity and potential for miniaturization. It is shown that an optomechanical sensor can potentially outperform state-of-the-art magnetometers of similar size, in particular other sensors based on a magnetostrictive mechanism.
基金the Defense Science and Technology Advance-research for Ship Industry
文摘That whether unidirectional tension changes the influence of incident angle on FSS's(frequency selective surface) electromagnetic(EM) property and whether incident angle changes the effect of unidirectional intension on FSS's EM property is researched.The pattern and magnitude of these changes are revealed.Firstly,the analyses for the mechanism of unidirectional tension's influence and the mechanism of the coupling between the influences of unidirectional tension and incident angle are conducted.Then,according to the mechanism of these influences,Mechanics-Electromagnetics co-analysis is conducted based on mechanics finite element method and electromagnetics finite element method.The frequency responses of the FSS which is under different unidirectional tensions and illuminated by EM wave incident at different angles are gained.The concept"unidirectional tensile sensitivity of FSS"is put forward along with two unidirectional tensile sensitivity factors.By using angular sensitivity-factor and unidirectional tensile sensitivity-factor,the influences of unidirectional tension and incident angle,which are coupled with each other,are expatiated respectively.Research results show that these influences have two sides.Meanwhile,basing on Mode Matching Method and according to the results of numerical investigation,one principle for the layout of FSS with apertures is gained.Several suggestions for further research are given.
