A novel optimal design of sub-wavelength metal rectangular gratings for the polarizing beam splitter （PBS） is proposed. The method is based on effective medium theory and the method of designing single layer antiref...A novel optimal design of sub-wavelength metal rectangular gratings for the polarizing beam splitter （PBS） is proposed. The method is based on effective medium theory and the method of designing single layer antireflection coating. The polarization performance of PBS is discussed by rigorous couple-wave analysis （RCWA） method at a wavelength of 1550 nm. The result shows that sub-wavelength metal rectangular grating is characterized by a high reflectivity, like metal films for TE polarization, and high transmissivity, like dielectric films for TM polarization. The optimal design accords well with the results simulated by RCWA method.展开更多
Deep sub-wavelength metamaterials are the key to the further development of practical metamaterials with small volumes and broadband properties. We propose to reduce the electrical sizes of metamaterials down to more ...Deep sub-wavelength metamaterials are the key to the further development of practical metamaterials with small volumes and broadband properties. We propose to reduce the electrical sizes of metamaterials down to more sub-wavelength scales by lowering the plasma frequencies of metallic wires. The theoretical model is firstly established by analyzing the plasma frequency of continuous thin wires. By introducing more inductance elements, the effective electron mass can be enhanced drastically, leading to significantly lowered plasma frequencies. Based on this theory, we demonstrate that both the electric and the magnetic plasma frequencies of metamaterials can be lowered significantly and thus the electrical sizes of metamaterials can be reduced to more sub-wavelength scales. This provides an efficient route to deep sub-wavelength metamaterials and will give rigorous impetus for the further development of practical metamaterials.展开更多
The Stokes spectrum in the stimulated Raman scattering (SRS) is very complicated. In this article, we use both Gaussian and Lorentz approximation to investigate the gain properties of multi pumping broadband Raman amp...The Stokes spectrum in the stimulated Raman scattering (SRS) is very complicated. In this article, we use both Gaussian and Lorentz approximation to investigate the gain properties of multi pumping broadband Raman amplifier, and present some schemes for flattening the gain. All the results show that the flatness of the gain spectrum is closely related to the pumping frequency grid. By researching the gain properties of Raman amplifiers of such ITU-T fibers as G.652, G.653, G.655 and large effective area non zero dispersion flattening fiber, we find that the Raman gain is associated with the fiber type and its transmission characteristics, especially it decreases with the increase of the effective core area.展开更多
Spectra of KX-rays emitted from pure 3 dtransition metals and their oxide and sulfate compounds were measured using a single crystal wavelength dispersive X-ray spectroscopy(WDXRF).The measurements were performed usin...Spectra of KX-rays emitted from pure 3 dtransition metals and their oxide and sulfate compounds were measured using a single crystal wavelength dispersive X-ray spectroscopy(WDXRF).The measurements were performed using a ZSX-100 esequential spectrometer equipped with an RhX-ray tube operated.An accurate analytical representation of each line was obtained by a fit to a Lorentz function.The spectra were analyzed in order to examine the KX-ray peak parameters such as asymmetry index,peak energy and relative intensity ratios.The energy shifts and relative intensities weredetermined tobetter understand the chemical effect.展开更多
In the twenty first century research works, there may be a need to achieve a more reliable research result through a synergy between engineers and biological researchers. The peak absorbance data for various interacti...In the twenty first century research works, there may be a need to achieve a more reliable research result through a synergy between engineers and biological researchers. The peak absorbance data for various interacting systems were measured. These were used to show that the antiretroviral drug has the effect of increasing the peak absorbance values of both the uninfected and infected blood components, i.e., the drugs are made able to increase the light absorption capacity of the blood cells. For drug 2 that contains three components including Efavirenz, the drug effect on lymphocytes was increased by about 38% for patients that had been on antiretroviral drug treatment. Mathematical models were proposed and used in determining the coating effectiveness of antiretroviral drugs in the presence and absence of HIV. The use of the findings of this work by pharmaceutical industries may help in the search for more effective antiretroviral drugs for the treatment of HIV patients.展开更多
As energy gradually becomes a more valuable commodity, the desire for reduced energy losses strengthens. Lighting is a critical field on this matter, as it accounts for a large percentage of the global electricity con...As energy gradually becomes a more valuable commodity, the desire for reduced energy losses strengthens. Lighting is a critical field on this matter, as it accounts for a large percentage of the global electricity consumption and modern lighting systems are greatly more efficient than incandescent, discharge, and fluorescent lights. Previous research has proven that plants do not require the entire visible spectrum but react only to specific wavelengths, making it possible to control their growth and yield via artificial lighting. The flexibility of control of Light Emitting Diode (LED) lights allows for the combination of great energy losses reduction and controlled plant growth, achieving the improvement of two major parameters in a single action. This review paper summarizes the current research on the effect different light wavelengths have on specific plant species and discusses the applications of LED lighting for horticulture, yield storage, and disease protection.展开更多
After a theoretical model is put forward on the base of accurate description of the Raman gain profile and the physical quantity, maximum Raman crosstalk(MRC), which quantificationally depicts the intensity of Raman c...After a theoretical model is put forward on the base of accurate description of the Raman gain profile and the physical quantity, maximum Raman crosstalk(MRC), which quantificationally depicts the intensity of Raman crosstalk is defined. The influences of launch power, fiber effective core area, fiber nonlinear index, fiber length, channel number and channel interval on MRC are deduced. The result indicates that compared with low speed and narrowband optical fiber communication system, serious Raman crosstalk lies in high speed and broadband system, which impacts the performance of the system badly. The result is useful for forecasting Raman crosstalk in broadband and high speed optical fiber communication system.展开更多
基金Project supported by Science Foundation of the Chongqing Committee of Education,China (Grant No KJ071205)
文摘A novel optimal design of sub-wavelength metal rectangular gratings for the polarizing beam splitter （PBS） is proposed. The method is based on effective medium theory and the method of designing single layer antireflection coating. The polarization performance of PBS is discussed by rigorous couple-wave analysis （RCWA） method at a wavelength of 1550 nm. The result shows that sub-wavelength metal rectangular grating is characterized by a high reflectivity, like metal films for TE polarization, and high transmissivity, like dielectric films for TM polarization. The optimal design accords well with the results simulated by RCWA method.
基金supported by the National Natural Science Foundation of China(Grants Nos.11204378 and 11274389)the Natural Science Foundation of Shaanxi Province,China(Grant No.2011JQ8031)
文摘Deep sub-wavelength metamaterials are the key to the further development of practical metamaterials with small volumes and broadband properties. We propose to reduce the electrical sizes of metamaterials down to more sub-wavelength scales by lowering the plasma frequencies of metallic wires. The theoretical model is firstly established by analyzing the plasma frequency of continuous thin wires. By introducing more inductance elements, the effective electron mass can be enhanced drastically, leading to significantly lowered plasma frequencies. Based on this theory, we demonstrate that both the electric and the magnetic plasma frequencies of metamaterials can be lowered significantly and thus the electrical sizes of metamaterials can be reduced to more sub-wavelength scales. This provides an efficient route to deep sub-wavelength metamaterials and will give rigorous impetus for the further development of practical metamaterials.
文摘The Stokes spectrum in the stimulated Raman scattering (SRS) is very complicated. In this article, we use both Gaussian and Lorentz approximation to investigate the gain properties of multi pumping broadband Raman amplifier, and present some schemes for flattening the gain. All the results show that the flatness of the gain spectrum is closely related to the pumping frequency grid. By researching the gain properties of Raman amplifiers of such ITU-T fibers as G.652, G.653, G.655 and large effective area non zero dispersion flattening fiber, we find that the Raman gain is associated with the fiber type and its transmission characteristics, especially it decreases with the increase of the effective core area.
基金the Scientific and Technological Research Council of Turkey (TUBITAK), under the project No. 10GT045
文摘Spectra of KX-rays emitted from pure 3 dtransition metals and their oxide and sulfate compounds were measured using a single crystal wavelength dispersive X-ray spectroscopy(WDXRF).The measurements were performed using a ZSX-100 esequential spectrometer equipped with an RhX-ray tube operated.An accurate analytical representation of each line was obtained by a fit to a Lorentz function.The spectra were analyzed in order to examine the KX-ray peak parameters such as asymmetry index,peak energy and relative intensity ratios.The energy shifts and relative intensities weredetermined tobetter understand the chemical effect.
文摘In the twenty first century research works, there may be a need to achieve a more reliable research result through a synergy between engineers and biological researchers. The peak absorbance data for various interacting systems were measured. These were used to show that the antiretroviral drug has the effect of increasing the peak absorbance values of both the uninfected and infected blood components, i.e., the drugs are made able to increase the light absorption capacity of the blood cells. For drug 2 that contains three components including Efavirenz, the drug effect on lymphocytes was increased by about 38% for patients that had been on antiretroviral drug treatment. Mathematical models were proposed and used in determining the coating effectiveness of antiretroviral drugs in the presence and absence of HIV. The use of the findings of this work by pharmaceutical industries may help in the search for more effective antiretroviral drugs for the treatment of HIV patients.
文摘As energy gradually becomes a more valuable commodity, the desire for reduced energy losses strengthens. Lighting is a critical field on this matter, as it accounts for a large percentage of the global electricity consumption and modern lighting systems are greatly more efficient than incandescent, discharge, and fluorescent lights. Previous research has proven that plants do not require the entire visible spectrum but react only to specific wavelengths, making it possible to control their growth and yield via artificial lighting. The flexibility of control of Light Emitting Diode (LED) lights allows for the combination of great energy losses reduction and controlled plant growth, achieving the improvement of two major parameters in a single action. This review paper summarizes the current research on the effect different light wavelengths have on specific plant species and discusses the applications of LED lighting for horticulture, yield storage, and disease protection.
基金Supported by the Teaching and Research Award Program for Outstanding Young Teachers in Higher Education Institute of MOE, P.R.C.
文摘After a theoretical model is put forward on the base of accurate description of the Raman gain profile and the physical quantity, maximum Raman crosstalk(MRC), which quantificationally depicts the intensity of Raman crosstalk is defined. The influences of launch power, fiber effective core area, fiber nonlinear index, fiber length, channel number and channel interval on MRC are deduced. The result indicates that compared with low speed and narrowband optical fiber communication system, serious Raman crosstalk lies in high speed and broadband system, which impacts the performance of the system badly. The result is useful for forecasting Raman crosstalk in broadband and high speed optical fiber communication system.
