Real-time water-medium endoscopic images can assist doctors in performing operations such as tissue cleaning and nucleus pulpous removal.During medical operating procedures,it is inevitable that tissue particles,debri...Real-time water-medium endoscopic images can assist doctors in performing operations such as tissue cleaning and nucleus pulpous removal.During medical operating procedures,it is inevitable that tissue particles,debris and other contaminants will be suspended within the viewing area,resulting in blurred images and the loss of surface details in biological tissues.Currently,few studies have focused on enhancing such endoscopic images.This paper proposes a water-medium endoscopic image processing method based on dual transmittance in accordance with the imaging characteristics of spinal endoscopy.By establishing an underwater imaging model for spinal endoscopy,we estimate the transmittance of the endoscopic images based on the boundary constraints and local image contrast.The two transmittances are then fused and combined with transmittance maps and ambient light estimations to restore the images before attenuation,ultimately enhancing the details and texture of the images.Experiments comparing classical image enhancement algorithms demonstrate that the proposed algorithm could effectively improve the quality of spinal endoscopic images.展开更多
We synthesized tungsten-doped vanadium dioxide(W-VO_(2))particles via a one-step hydrothermal method,followed by their integration with antimony-doped tin oxide(ATO)nanoparticles to formulate a composite coating.Subse...We synthesized tungsten-doped vanadium dioxide(W-VO_(2))particles via a one-step hydrothermal method,followed by their integration with antimony-doped tin oxide(ATO)nanoparticles to formulate a composite coating.Subsequently,the VO_(2)/ATO composite coating was fabricated through a spin-coating process.The impact of varying W-VO_(2) content and coating thickness on the performance of the composite coatings was systematically investigated by employing X-ray diffraction,particle size distribution analysis,spectrometry,and other pertinent test methodologies.Our findings revealed that an escalation in both W-VO_(2) content and coating thickness retained high transmittance in the near-infrared band at lower temperatures.However,as the temperature increased,a notable reduction in transmittance in the near-infrared band was observed,alongside a slight decrease in transmittance within the visible band.Remarkably,when the W-VO_(2) content reached 5%and the coating thickness was 1253 nm,the transmittance of the composite coating surpassed 80%.Furthermore,the heat insulation effect achieved a remarkable 10.0℃increase.Consequently,the synthesized composite coating demonstrates significant potential for smart glass applications,particularly in the realm of heat-insulating glass.展开更多
The presence of Li_(2)Si_(2)O_(5) and LiAlSi_(4)O_(10) could effectively improve the elastic modulus and transmittance of lithium disilicate(LD)glass-ceramics.Through synergistically modulation of the crystal content ...The presence of Li_(2)Si_(2)O_(5) and LiAlSi_(4)O_(10) could effectively improve the elastic modulus and transmittance of lithium disilicate(LD)glass-ceramics.Through synergistically modulation of the crystal content and grain size,we obtained high strength and high transmittance of LD glass-ceramics.The optimal sample had a high transmittance of 90.3%,the hardness was 7.72 GPa,the fracture toughness was 1.07 MPa·m^(1/2),and the elastic modulus was 103.1 GPa.展开更多
[Objective] To explore a method for the rapid determination of protein con- tent in grains of Panicum miliaceum L. [Method] The near infrared transmittance spec- troscopy （NITS） was used to build the mathematical mo...[Objective] To explore a method for the rapid determination of protein con- tent in grains of Panicum miliaceum L. [Method] The near infrared transmittance spec- troscopy （NITS） was used to build the mathematical models for the quantitative analy- sis of protein content in the grains. Four combinations of treatment that first derivative and second derivative were respectively combined with partial least squares （PLS） and modified partial least squares （MPLS） were set to compare their effects on the original transmission spectrum. [Result] The predicting effects of the 4 combinations were similar. The optimal combination was first derivative with MPLS, in which the average determination coefficient of validation （RSQ） was 0.880 6, correlation coeffi- cient of cross validation （1-VR） was 0.857 0, standard error of calibration （SEC） was 0.342 4, standard error of cross validation （SECV） was 0.375 1, and the standard er- ror of prediction （SEP） was 0.454. [Conclusion] The constructed NITS model is a rapid way for the determination of protein content in grains of P. miliaceum.展开更多
The Malkmus band model has been widely used in remote sensing and climate studies. However, its accuracy is not high. To solve this problem, a modified Malkmus band model was proposed by introducing a correction item....The Malkmus band model has been widely used in remote sensing and climate studies. However, its accuracy is not high. To solve this problem, a modified Malkmus band model was proposed by introducing a correction item. The HITRAN (High-resolution TRANsmission) 2008 database and the atmospheric models provided by the Air Force Geophysics Laboratory (AFGL) were used to calculate the molecular transmittances. By fitting the calculated transmittances to those by MODTRAN (MODerate resolution atmospheric TRANsmission) package with the least-squares method, the fitting coefficients of the correction item were obtained under different atmosphere models. The experimental results show that the root mean square errors (RMSE) of the modified model are significantly less than that of the traditional Malkmus band model by 1-2 orders of magnitude. In addition, the modified method is suitable for different atmospheric models and molecules.展开更多
[Objective] The aim of this study was to establish a reversed phase high-performance liquid chromatography（RP-HPLC）method for the content determination of Co-Q10.[Method] The RP-HPLC method was used to detect the Co...[Objective] The aim of this study was to establish a reversed phase high-performance liquid chromatography（RP-HPLC）method for the content determination of Co-Q10.[Method] The RP-HPLC method was used to detect the Co-Q10,and the ultraviolet spectro-photometry was used to analyze the daily change of transmittance of Co-Q10.[Result] By using RP-HPLC,Co-Q10 had a good linear relationship between 40-300 μg/ml（r=0.999 9）.The limit of detection was 0.4 ng and the average recovery was 97.44%（n=3）.The system suitability of HP-HPLC was good,and the average recovery and precision results could meet the needs of assay.[Conclusion] This method was convenient,accurate and reproducible and could be used in quality control of Co-Q10.However,when it operates,light should be evaded.展开更多
Aluminum-doped zinc oxide (AZO) thin films were deposited on sapphire (002) and glass substrates by two different sputtering techniques radio frequency magnetron cosputtering of AZO and ZnO targets and sputtering of a...Aluminum-doped zinc oxide (AZO) thin films were deposited on sapphire (002) and glass substrates by two different sputtering techniques radio frequency magnetron cosputtering of AZO and ZnO targets and sputtering of an AZO target. The dependence of the photoluminescence (PL) and transmittance properties of the AZO films deposited by cosputtering and sputtering on the AZO/ZnO target power ratio, R and the O2/Ar flow ratio, r were investigated, respectively. Only a deep level emission peak appears in the PL spectra of cosputtered AZO films whereas both UV emission and deep level emission peaks are observed in the PL spectra of sputtered AZO films. The absorption edges in the transmittance spectra of the AZO films shift to the lower wavelength region as R and r increase. Effects of crystallinity, surface roughness, PL on the transmittance of the AZO films were also explained using the X-ray diffraction (XRD), atomic force microscopy (AFM), and PL analysis results.展开更多
The infrared transmittance and emissivity of heat-insulating coatings pigmented with various structural particles were studied using Kubelka-Munk theory and Mie theory. The primary design purpose was to obtain the low...The infrared transmittance and emissivity of heat-insulating coatings pigmented with various structural particles were studied using Kubelka-Munk theory and Mie theory. The primary design purpose was to obtain the low transmittance and low emissivity coatings to reduce the heat transfer by thermal radiation for high-temperature applications. In the case of silica coating layers constituted with various structural titania particles （solid, hollow, and core-shell spherical）, the dependence of transmittance and emissivity of the coating layer on the particle structure and the layer thickness was investigated and optimized. The results indicate that the coating pigmented with core-shell titania particles exhibits a lower infrared transmittance and a lower emissivity value than that with other structural particles and is suitable to radiative heat-insulating applications.展开更多
Watermelon is a popular fruit in the world with soluble solids content （SSC） being one of the major characteristics used for assessing its quality. This study was aimed at obtaining a method for nondestructive SSC d...Watermelon is a popular fruit in the world with soluble solids content （SSC） being one of the major characteristics used for assessing its quality. This study was aimed at obtaining a method for nondestructive SSC detection of watermelons by means of visible/near infrared （Vis/NIR） diffuse transmittance technique. Vis/NIR transmittance spectra of intact watermelons were acquired using a low-cost commercially available spectrometer operating over the range 350-1000 nm. Spectra data were analyzed by two multivariate calibration techniques： partial least squares （PLS） and principal component regression （PCR） methods. Two experiments were designed for two varieties of watermelons [Qilin （QL）, Zaochunhongyu （ZC）], which have different skin thickness range and shape dimensions. The influences of different data preprocessing and spectra treatments were also investigated. Performance of different models was assessed in terms of root mean square errors of calibration （RMSEC）, root mean square errors of prediction （RMSEP） and correlation coefficient （r） between the predicted and measured parameter values. Results showed that spectra data preprocessing influenced the performance of the calibration models. The first derivative spectra showed the best results with high correlation coefficient of determination [r=0.918 （QL）; r=0.954 （ZC）], low RMSEP [0.65 °Brix （QL）; 0.58 °Brix （ZC）], low RMSEC [0.48 °Brix （QL）; 0.34°Brix （ZC）] and small difference between the＇RMSEP and the RMSEC by PLS method. The nondestructive Vis/NIR measurements provided good estimates of SSC index of watermelon, and the predicted values were highly correlated with destructively measured values for SSC. The models based on smoothing spectra （Savitzky-Golay filter smoothing method） did not enhance the performance of calibration models obviously. The results indicated the feasibility of Vis/NIR diffuse transmittance spectral analysis for predicting watermelon SSC in a nondestructive way.展开更多
Vinyl-containingtitanium-silphenylene-sioxane oligomers(O1,O2,O3,andO4)withdifferent molar ratios of titanium to silicon were successfully synthesized in high yields by nonhydrolytic sol-gel reaction,and the obtained ...Vinyl-containingtitanium-silphenylene-sioxane oligomers(O1,O2,O3,andO4)withdifferent molar ratios of titanium to silicon were successfully synthesized in high yields by nonhydrolytic sol-gel reaction,and the obtained four oligomers were further crosslinked with methylphenyl hydro-silicone oil(4)to form corresponding polymers(P1,P2,P3,and P4)by hydrosilylation reaction.Their structures were characterized with spectroscopic characterization techniques including FTIR,1H-NMR,and Raman spectroscopy.The effect of titanium element on crosslinking behavior,thermal resistance,refractive index,transparency,thermal aging stability,glass transition temperature,and surface properties of the polymers were studied.Compared with titanium-free polymer P1,the thermal resistance,refractive index,and thermal aging stability of titanium-silphenylene-siloxane polymers(P2,P3,and P4)were significantly improved.The titanium-silphenylene-siloxane polymers achieved a high refractive index(n=1.580-1.584)and thermostability(Tsd>500℃).In thermal aging,the polymers exhibited superior performances with high optical transparency(~90%at 450 nm)and exhibited high thermal stability(~84%at 450 nm after thermal aging at 150℃for 120 h).These data indicate that the polymers have potential application in optical materials such as LED encapsulants.展开更多
Plasma photonic crystals(PPCs) have been a hot research topic in the band gap(BG) material field in recent years due to their unique advantages, such as the feasibility of changing the parameters and hence the propert...Plasma photonic crystals(PPCs) have been a hot research topic in the band gap(BG) material field in recent years due to their unique advantages, such as the feasibility of changing the parameters and hence the properties of the materials with respect to traditional photonic crystals(PCs). In this paper,we focus mainly on the effects of some types of defects introduced in PPCs on the changes in BG characteristics of microwave(MW) transmittance. The research is carried out using numerical simulation with a one-dimensional finite-difference time-domain(FDTD) method, and six types of defects, including a lattice-constant defect, radii-ratio defect, additional-column defect, column-width defect, plasma-frequency defect, and electron-collision-frequency defect, are concerned. It transpires that introducing a defect in a PPC in different manners may realize the symmetric change, alternative change, shifting, generating, transforming, disappearing, and attenuating of BGs in transmittance spectra, which has great potential for the manufacture of spatiotemporal-controllable MW materials and devices with more feasible modulating functions.展开更多
Electron beam（EB） irradiation experiments on Au/ITO and ITO/Au/ITO multilayer thin films are reported.The structure and the optical-electrical properties of the samples were investigated by X-ray diffraction,atomic ...Electron beam（EB） irradiation experiments on Au/ITO and ITO/Au/ITO multilayer thin films are reported.The structure and the optical-electrical properties of the samples were investigated by X-ray diffraction,atomic force microscopy, four-point probe resistivity measurement system, and UV–vis-NIR double beam spectrometer, respectively. Those results show that the EB irradiation has the effects of improving the crystalline of samples, widening the optical band gap of both thin films, reducing the sheet resistance,and improving the transmittance of samples.展开更多
A parameterized transmittance model （PTR） for ozone and water vapor monochromatic transmittance calculation in the solar-to-near-infrared spectrum 0.3-4 pm with a spectral resolution of 5 cm-1 was developed based on...A parameterized transmittance model （PTR） for ozone and water vapor monochromatic transmittance calculation in the solar-to-near-infrared spectrum 0.3-4 pm with a spectral resolution of 5 cm-1 was developed based on the transmittance data calculated by Moderate-resolution Transmittance model （MOD- TRAN）. Polynomial equations were derived to represent the transmittance as functions of path length and airmass for every wavelength based on the least-squares method. Comparisons between the transmittances calculated using PTR and MODTRAN were made, using the results of MODTRAN as a reference. Rela- tive root-mean-square error （RMSre） was 0.823% for ozone transmittance. RMSre values were 8.84~ and 3.48~ for water vapor transmittance ranges of 1-1 x 10-is and 1-1x 10-3, respectively. In addition, the Stratospheric Aerosol and Gas Experiment II （SAGEII） ozone profiles and University of Wyoming （UWYO） water vapor profiles were applied to validate the applicability of PTR model. RMSre was 0.437~ for ozone transmittance. RMSre values were 8.89~ and 2.43% for water vapor transmittance ranges of 1-1~10-is and 1-1~ 10-6, respectively. Furthermore, the optical depth profiles calculated using the PTR model were compared to the results of MODTRAN. Absolute RMS errors （RMSab） for ozone optical depths were within 0.0055 and 0.0523 for water vapor at all of the tested altitudes. Finally, the comparison between the solar heating rate calculated from the transmittance of PTR and Line-by-Line radiative transfer model （LBLRTM） was performed, showing a maximum deviation of 0.238 K d-1 （6% of the corresponding solar heating rate calculated using LBLRTM）. In the troposphere all of the deviations were within 0.08 K d-1. The computational speed of PTR model is nearly two orders of magnitude faster than that of MODTRAN.展开更多
Plasma photonic crystals(PPCs)are emerging as a powerful instrument for the dynamical control of the electromagnetic properties of a propagating wave.Here we demonstrate several one-dimensional(1 D)PPCs with uniquely ...Plasma photonic crystals(PPCs)are emerging as a powerful instrument for the dynamical control of the electromagnetic properties of a propagating wave.Here we demonstrate several one-dimensional(1 D)PPCs with uniquely designed superlattice structures,annular structures or with incorporation of the third material into the primitive unit cell.The influences of the properties of the third material as well as the structural configurations of suplerlattices on the transmittance characteristics of PPCs have been investigated by use of the finite element method.The optimal design strategy for producing PPCs that have more and larger band gaps is provided.These new schemes can potentially be extended to 2 D or 3 D plasma crystals,which may find broad applications in the manipulation of microwaves and terahertz waves.展开更多
Mid-infrared transmittance of submicron silver slit arrays was numerically studied with the finite difference time domain method. The slit width varies from 50 nm to 300 nm and a square feature may attach at either or...Mid-infrared transmittance of submicron silver slit arrays was numerically studied with the finite difference time domain method. The slit width varies from 50 nm to 300 nm and a square feature may attach at either or both slit sides. Although the side length of features is one or two orders of magnitude shorter than the wavelength, the attached nanoscale features can modify the transmittance significantly. The transmittance was also further investigated in detail by looking into the electromagnetic fields and Poynting vectors of selected slit geometries. The investigation results show that such change can be attributed to the cavity resonance effect inside the slit arrays. The work is of great importance to the wavelength-selective devices design in optical devices and thermal application fields.展开更多
This paper presents the global solar radiation (GSR) and cloud transmittance factor (cf) measured at the horizontal surface over a period of one year from 2009 to 2010 using CMP6 Pyranometer and NILUUV Irradiance Mete...This paper presents the global solar radiation (GSR) and cloud transmittance factor (cf) measured at the horizontal surface over a period of one year from 2009 to 2010 using CMP6 Pyranometer and NILUUV Irradiance Meter at Lukla (Latitude 26.69oN,Longitude 86.73?E and Altitude 2850 m) in the foothills of the Mt Everest (8850 m high). Monthly and seasonal variations of global solar radiation as well as correlation between clearness index and cloud transmittance factor at Lukla are presented. The annual average daily global solar radiation is about 3.83 kWh/sq·m/day which is sufficient to promote solar active and passive energy technology at high mountain terrain where there is no other viable alternative sources of energy. The maximum and minimum global solar radiation of 5.33 and 2.08 kWh/sq·m/day is recorded in April and September 2010 respectively. The seasonal variation of solar energy is about 2.87 kWh/sq·m/day and 4.83 kWh/sq·m/day in summer and spring respectively which is not in line with the general trend. The coefficient of determination (R2) between cloud transmittance factor (cf) and clearness factor (K) is found to be 0.97. This novel result can be utilized to estimate the global solar radiation at the horizontal surface where K and cf are available.展开更多
Ceramics usually have irregular grains, cracking, or porosity, which result in their lightproof.Y2Mo3O12 ceramics have more porosity due to the heavy hygroscopicity.Introducing ZnLi to Y2Mo3O12 could form regular grai...Ceramics usually have irregular grains, cracking, or porosity, which result in their lightproof.Y2Mo3O12 ceramics have more porosity due to the heavy hygroscopicity.Introducing ZnLi to Y2Mo3O12 could form regular grains, reduce cracking and porosity.With increasing the content of ZnLi, the grain shapes self-assembly gradually and then the laser scattering and transmittance improve.The laser scattering property and transmittance of diverging rays become the best in ceramics Y2-x(ZnLi)xMo3O12(x = 1.0 and 1.2) with regular grains and low thermal expansion.The formation mechanism of regular grains is ascribed to the substitutions of Zn^2+ and Li+for Y^3+ in Y2Mo3O12 resulting in the preferential growth.The investigation in laser scattering, transmittance and low thermal expansion behaviors of Y2-x(ZnLi)xMo3O12 could pave a way to weaken the strong-laser attack from the high-power laser weapon and the other.展开更多
The phase transition behaviors of the shocked water are investigated by employing an optical transmittance in-situ detection system.Based on the light scattering theory and phase transformation kinetics,the phase tran...The phase transition behaviors of the shocked water are investigated by employing an optical transmittance in-situ detection system.Based on the light scattering theory and phase transformation kinetics,the phase transition mechanism of the water under multiple shocks is discussed.The experimental data indicate that the evolution of the transmittance of the shocked water can be broadly divided into three stages:relaxation stage,decline stage,and recovery stage.In the early stage of the phase transition,the new phase particles began to form around the quartz/window interface.It should be mentioned that the water/ice phase boundary seems to move toward the liquid region in one experiment of this work.Due to the new phase core being much smaller than the wavelength of the incident light,the transmittance of the sample within the relaxation stage remains steady.The decline stage can be divided into the rapid descent stage and the slow descent stage in this work,which is considered as the different growth rates of the new phase particle under different shock loadings.The recovery stage is attributed to the emergence of the new phase particles which are bigger than the critical value.However,the influence of the size growth and the population growth of the new phase particles on the transmittance restrict each other,which may be responsible for the phenomenon that the transmittance curve does not return to the initial level.展开更多
Measurement-device-independent quantum key distribution(MDI-QKD) is immune to detector side channel attacks, which is a crucial security loophole problem in traditional QKD. In order to relax a key assumption that the...Measurement-device-independent quantum key distribution(MDI-QKD) is immune to detector side channel attacks, which is a crucial security loophole problem in traditional QKD. In order to relax a key assumption that the sources are trusted in MDI-QKD, an MDI-QKD protocol with an untrusted source has been proposed. For the security of MDI-QKD with an untrusted source, imperfections in the practical experiment should also be taken into account. In this paper, we analyze the effects of fluctuations of internal transmittance on the security of a decoy-state MDI-QKD protocol with an untrusted source. Our numerical results show that both the secret key rate and the maximum secure transmission distance decrease when taken fluctuations of internal transmittance into consideration. Especially, they are more sensitive when Charlie's mean photon number per pulse is smaller. Our results emphasize that the stability of correlative optical devices is important for practical implementations.展开更多
This paper investigates the photon tunneling and transmittance resonance through a multi-layer structure including a left-handed material（LHM）. An analytical expression for the transmittance in a five-layer structur...This paper investigates the photon tunneling and transmittance resonance through a multi-layer structure including a left-handed material（LHM）. An analytical expression for the transmittance in a five-layer structure is given by the analytical transfer matrix method. The transmittance is studied as a function of the refractive index and the width of the LHM layer. The perfect photon tunneling results from the multi-layer structure, especially from the relation between the magnitude of the refractive index and the width of the LHM layer and those of the adjoining layers. Photons may tunnel through a much greater distance in this structure. Transmittance resonance happens, the peaks and valleys appear periodically at the resonance thickness. For an LHM with inherent losses, the perfect transmittance is suppressed.展开更多
文摘Real-time water-medium endoscopic images can assist doctors in performing operations such as tissue cleaning and nucleus pulpous removal.During medical operating procedures,it is inevitable that tissue particles,debris and other contaminants will be suspended within the viewing area,resulting in blurred images and the loss of surface details in biological tissues.Currently,few studies have focused on enhancing such endoscopic images.This paper proposes a water-medium endoscopic image processing method based on dual transmittance in accordance with the imaging characteristics of spinal endoscopy.By establishing an underwater imaging model for spinal endoscopy,we estimate the transmittance of the endoscopic images based on the boundary constraints and local image contrast.The two transmittances are then fused and combined with transmittance maps and ambient light estimations to restore the images before attenuation,ultimately enhancing the details and texture of the images.Experiments comparing classical image enhancement algorithms demonstrate that the proposed algorithm could effectively improve the quality of spinal endoscopic images.
基金Funded by Beijing Municipal Science&Technology Commission,Administrative Commission of Zhongguancun Science Park(No.Z221100006722022)。
文摘We synthesized tungsten-doped vanadium dioxide(W-VO_(2))particles via a one-step hydrothermal method,followed by their integration with antimony-doped tin oxide(ATO)nanoparticles to formulate a composite coating.Subsequently,the VO_(2)/ATO composite coating was fabricated through a spin-coating process.The impact of varying W-VO_(2) content and coating thickness on the performance of the composite coatings was systematically investigated by employing X-ray diffraction,particle size distribution analysis,spectrometry,and other pertinent test methodologies.Our findings revealed that an escalation in both W-VO_(2) content and coating thickness retained high transmittance in the near-infrared band at lower temperatures.However,as the temperature increased,a notable reduction in transmittance in the near-infrared band was observed,alongside a slight decrease in transmittance within the visible band.Remarkably,when the W-VO_(2) content reached 5%and the coating thickness was 1253 nm,the transmittance of the composite coating surpassed 80%.Furthermore,the heat insulation effect achieved a remarkable 10.0℃increase.Consequently,the synthesized composite coating demonstrates significant potential for smart glass applications,particularly in the realm of heat-insulating glass.
基金Funded by the National Natural Science Foundation of China(No.52372014)the Key R&D Project of Hubei Province(No.2022BAA025)the Key R&D Project of Jincheng City(No.20220120)。
文摘The presence of Li_(2)Si_(2)O_(5) and LiAlSi_(4)O_(10) could effectively improve the elastic modulus and transmittance of lithium disilicate(LD)glass-ceramics.Through synergistically modulation of the crystal content and grain size,we obtained high strength and high transmittance of LD glass-ceramics.The optimal sample had a high transmittance of 90.3%,the hardness was 7.72 GPa,the fracture toughness was 1.07 MPa·m^(1/2),and the elastic modulus was 103.1 GPa.
基金Supported by the National Key Technology R&D Program of China (2006BAD02B07)the National Mordern Agricultural Industry System of China(CARS-07-12.5-A12)~~
文摘[Objective] To explore a method for the rapid determination of protein con- tent in grains of Panicum miliaceum L. [Method] The near infrared transmittance spec- troscopy （NITS） was used to build the mathematical models for the quantitative analy- sis of protein content in the grains. Four combinations of treatment that first derivative and second derivative were respectively combined with partial least squares （PLS） and modified partial least squares （MPLS） were set to compare their effects on the original transmission spectrum. [Result] The predicting effects of the 4 combinations were similar. The optimal combination was first derivative with MPLS, in which the average determination coefficient of validation （RSQ） was 0.880 6, correlation coeffi- cient of cross validation （1-VR） was 0.857 0, standard error of calibration （SEC） was 0.342 4, standard error of cross validation （SECV） was 0.375 1, and the standard er- ror of prediction （SEP） was 0.454. [Conclusion] The constructed NITS model is a rapid way for the determination of protein content in grains of P. miliaceum.
基金Projects(U1231105,41404013)supported by the National Natural Science Foundation of ChinaProject(2012AA121301)supported by the National Hi-tech Research and Development Program of China
文摘The Malkmus band model has been widely used in remote sensing and climate studies. However, its accuracy is not high. To solve this problem, a modified Malkmus band model was proposed by introducing a correction item. The HITRAN (High-resolution TRANsmission) 2008 database and the atmospheric models provided by the Air Force Geophysics Laboratory (AFGL) were used to calculate the molecular transmittances. By fitting the calculated transmittances to those by MODTRAN (MODerate resolution atmospheric TRANsmission) package with the least-squares method, the fitting coefficients of the correction item were obtained under different atmosphere models. The experimental results show that the root mean square errors (RMSE) of the modified model are significantly less than that of the traditional Malkmus band model by 1-2 orders of magnitude. In addition, the modified method is suitable for different atmospheric models and molecules.
基金Supported by Special Institutional Fund of Sichuan Agricultural University(06070904)~~
文摘[Objective] The aim of this study was to establish a reversed phase high-performance liquid chromatography（RP-HPLC）method for the content determination of Co-Q10.[Method] The RP-HPLC method was used to detect the Co-Q10,and the ultraviolet spectro-photometry was used to analyze the daily change of transmittance of Co-Q10.[Result] By using RP-HPLC,Co-Q10 had a good linear relationship between 40-300 μg/ml（r=0.999 9）.The limit of detection was 0.4 ng and the average recovery was 97.44%（n=3）.The system suitability of HP-HPLC was good,and the average recovery and precision results could meet the needs of assay.[Conclusion] This method was convenient,accurate and reproducible and could be used in quality control of Co-Q10.However,when it operates,light should be evaded.
文摘Aluminum-doped zinc oxide (AZO) thin films were deposited on sapphire (002) and glass substrates by two different sputtering techniques radio frequency magnetron cosputtering of AZO and ZnO targets and sputtering of an AZO target. The dependence of the photoluminescence (PL) and transmittance properties of the AZO films deposited by cosputtering and sputtering on the AZO/ZnO target power ratio, R and the O2/Ar flow ratio, r were investigated, respectively. Only a deep level emission peak appears in the PL spectra of cosputtered AZO films whereas both UV emission and deep level emission peaks are observed in the PL spectra of sputtered AZO films. The absorption edges in the transmittance spectra of the AZO films shift to the lower wavelength region as R and r increase. Effects of crystallinity, surface roughness, PL on the transmittance of the AZO films were also explained using the X-ray diffraction (XRD), atomic force microscopy (AFM), and PL analysis results.
文摘The infrared transmittance and emissivity of heat-insulating coatings pigmented with various structural particles were studied using Kubelka-Munk theory and Mie theory. The primary design purpose was to obtain the low transmittance and low emissivity coatings to reduce the heat transfer by thermal radiation for high-temperature applications. In the case of silica coating layers constituted with various structural titania particles （solid, hollow, and core-shell spherical）, the dependence of transmittance and emissivity of the coating layer on the particle structure and the layer thickness was investigated and optimized. The results indicate that the coating pigmented with core-shell titania particles exhibits a lower infrared transmittance and a lower emissivity value than that with other structural particles and is suitable to radiative heat-insulating applications.
基金Project supported by the National Natural Science Foundation of China (No. 30370371) and Program for New Century Excellent Talents in University (No. NCET-04-0524), China
文摘Watermelon is a popular fruit in the world with soluble solids content （SSC） being one of the major characteristics used for assessing its quality. This study was aimed at obtaining a method for nondestructive SSC detection of watermelons by means of visible/near infrared （Vis/NIR） diffuse transmittance technique. Vis/NIR transmittance spectra of intact watermelons were acquired using a low-cost commercially available spectrometer operating over the range 350-1000 nm. Spectra data were analyzed by two multivariate calibration techniques： partial least squares （PLS） and principal component regression （PCR） methods. Two experiments were designed for two varieties of watermelons [Qilin （QL）, Zaochunhongyu （ZC）], which have different skin thickness range and shape dimensions. The influences of different data preprocessing and spectra treatments were also investigated. Performance of different models was assessed in terms of root mean square errors of calibration （RMSEC）, root mean square errors of prediction （RMSEP） and correlation coefficient （r） between the predicted and measured parameter values. Results showed that spectra data preprocessing influenced the performance of the calibration models. The first derivative spectra showed the best results with high correlation coefficient of determination [r=0.918 （QL）; r=0.954 （ZC）], low RMSEP [0.65 °Brix （QL）; 0.58 °Brix （ZC）], low RMSEC [0.48 °Brix （QL）; 0.34°Brix （ZC）] and small difference between the＇RMSEP and the RMSEC by PLS method. The nondestructive Vis/NIR measurements provided good estimates of SSC index of watermelon, and the predicted values were highly correlated with destructively measured values for SSC. The models based on smoothing spectra （Savitzky-Golay filter smoothing method） did not enhance the performance of calibration models obviously. The results indicated the feasibility of Vis/NIR diffuse transmittance spectral analysis for predicting watermelon SSC in a nondestructive way.
基金National Key R&D Program of China(No.2016YFB0302105).
文摘Vinyl-containingtitanium-silphenylene-sioxane oligomers(O1,O2,O3,andO4)withdifferent molar ratios of titanium to silicon were successfully synthesized in high yields by nonhydrolytic sol-gel reaction,and the obtained four oligomers were further crosslinked with methylphenyl hydro-silicone oil(4)to form corresponding polymers(P1,P2,P3,and P4)by hydrosilylation reaction.Their structures were characterized with spectroscopic characterization techniques including FTIR,1H-NMR,and Raman spectroscopy.The effect of titanium element on crosslinking behavior,thermal resistance,refractive index,transparency,thermal aging stability,glass transition temperature,and surface properties of the polymers were studied.Compared with titanium-free polymer P1,the thermal resistance,refractive index,and thermal aging stability of titanium-silphenylene-siloxane polymers(P2,P3,and P4)were significantly improved.The titanium-silphenylene-siloxane polymers achieved a high refractive index(n=1.580-1.584)and thermostability(Tsd>500℃).In thermal aging,the polymers exhibited superior performances with high optical transparency(~90%at 450 nm)and exhibited high thermal stability(~84%at 450 nm after thermal aging at 150℃for 120 h).These data indicate that the polymers have potential application in optical materials such as LED encapsulants.
基金This work was partly supported by National Natural Science Foundation of China(No.11475019)。
文摘Plasma photonic crystals(PPCs) have been a hot research topic in the band gap(BG) material field in recent years due to their unique advantages, such as the feasibility of changing the parameters and hence the properties of the materials with respect to traditional photonic crystals(PCs). In this paper,we focus mainly on the effects of some types of defects introduced in PPCs on the changes in BG characteristics of microwave(MW) transmittance. The research is carried out using numerical simulation with a one-dimensional finite-difference time-domain(FDTD) method, and six types of defects, including a lattice-constant defect, radii-ratio defect, additional-column defect, column-width defect, plasma-frequency defect, and electron-collision-frequency defect, are concerned. It transpires that introducing a defect in a PPC in different manners may realize the symmetric change, alternative change, shifting, generating, transforming, disappearing, and attenuating of BGs in transmittance spectra, which has great potential for the manufacture of spatiotemporal-controllable MW materials and devices with more feasible modulating functions.
基金supported financially by the National Key Research and Development Program of China (No. 2016YFB1102303)the National Basic Research Program of China (973 Program) (No. 2015CB352001)the National Natural Science Foundation of China(No. 61378060)
文摘Electron beam（EB） irradiation experiments on Au/ITO and ITO/Au/ITO multilayer thin films are reported.The structure and the optical-electrical properties of the samples were investigated by X-ray diffraction,atomic force microscopy, four-point probe resistivity measurement system, and UV–vis-NIR double beam spectrometer, respectively. Those results show that the EB irradiation has the effects of improving the crystalline of samples, widening the optical band gap of both thin films, reducing the sheet resistance,and improving the transmittance of samples.
基金supported by the National Basic Research Program of China (Grant No.2011CB403401)the National Natural Sciences Foundation of China (Grant No. 41175029)
文摘A parameterized transmittance model （PTR） for ozone and water vapor monochromatic transmittance calculation in the solar-to-near-infrared spectrum 0.3-4 pm with a spectral resolution of 5 cm-1 was developed based on the transmittance data calculated by Moderate-resolution Transmittance model （MOD- TRAN）. Polynomial equations were derived to represent the transmittance as functions of path length and airmass for every wavelength based on the least-squares method. Comparisons between the transmittances calculated using PTR and MODTRAN were made, using the results of MODTRAN as a reference. Rela- tive root-mean-square error （RMSre） was 0.823% for ozone transmittance. RMSre values were 8.84~ and 3.48~ for water vapor transmittance ranges of 1-1 x 10-is and 1-1x 10-3, respectively. In addition, the Stratospheric Aerosol and Gas Experiment II （SAGEII） ozone profiles and University of Wyoming （UWYO） water vapor profiles were applied to validate the applicability of PTR model. RMSre was 0.437~ for ozone transmittance. RMSre values were 8.89~ and 2.43% for water vapor transmittance ranges of 1-1~10-is and 1-1~ 10-6, respectively. Furthermore, the optical depth profiles calculated using the PTR model were compared to the results of MODTRAN. Absolute RMS errors （RMSab） for ozone optical depths were within 0.0055 and 0.0523 for water vapor at all of the tested altitudes. Finally, the comparison between the solar heating rate calculated from the transmittance of PTR and Line-by-Line radiative transfer model （LBLRTM） was performed, showing a maximum deviation of 0.238 K d-1 （6% of the corresponding solar heating rate calculated using LBLRTM）. In the troposphere all of the deviations were within 0.08 K d-1. The computational speed of PTR model is nearly two orders of magnitude faster than that of MODTRAN.
基金supported by National Natural Science Foundation of China(No.11875014)the Natural Science Foundation of Hebei Province(A2017201099)。
文摘Plasma photonic crystals(PPCs)are emerging as a powerful instrument for the dynamical control of the electromagnetic properties of a propagating wave.Here we demonstrate several one-dimensional(1 D)PPCs with uniquely designed superlattice structures,annular structures or with incorporation of the third material into the primitive unit cell.The influences of the properties of the third material as well as the structural configurations of suplerlattices on the transmittance characteristics of PPCs have been investigated by use of the finite element method.The optimal design strategy for producing PPCs that have more and larger band gaps is provided.These new schemes can potentially be extended to 2 D or 3 D plasma crystals,which may find broad applications in the manipulation of microwaves and terahertz waves.
基金Project(N110402015) supported by the Fundamental Research Funds for the Central Universities of ChinaProject(2012M510075) supported by China Postdoctoral Science Foundation
文摘Mid-infrared transmittance of submicron silver slit arrays was numerically studied with the finite difference time domain method. The slit width varies from 50 nm to 300 nm and a square feature may attach at either or both slit sides. Although the side length of features is one or two orders of magnitude shorter than the wavelength, the attached nanoscale features can modify the transmittance significantly. The transmittance was also further investigated in detail by looking into the electromagnetic fields and Poynting vectors of selected slit geometries. The investigation results show that such change can be attributed to the cavity resonance effect inside the slit arrays. The work is of great importance to the wavelength-selective devices design in optical devices and thermal application fields.
文摘This paper presents the global solar radiation (GSR) and cloud transmittance factor (cf) measured at the horizontal surface over a period of one year from 2009 to 2010 using CMP6 Pyranometer and NILUUV Irradiance Meter at Lukla (Latitude 26.69oN,Longitude 86.73?E and Altitude 2850 m) in the foothills of the Mt Everest (8850 m high). Monthly and seasonal variations of global solar radiation as well as correlation between clearness index and cloud transmittance factor at Lukla are presented. The annual average daily global solar radiation is about 3.83 kWh/sq·m/day which is sufficient to promote solar active and passive energy technology at high mountain terrain where there is no other viable alternative sources of energy. The maximum and minimum global solar radiation of 5.33 and 2.08 kWh/sq·m/day is recorded in April and September 2010 respectively. The seasonal variation of solar energy is about 2.87 kWh/sq·m/day and 4.83 kWh/sq·m/day in summer and spring respectively which is not in line with the general trend. The coefficient of determination (R2) between cloud transmittance factor (cf) and clearness factor (K) is found to be 0.97. This novel result can be utilized to estimate the global solar radiation at the horizontal surface where K and cf are available.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.60976016,61350012,and 11574276)the Key Scientific Research Projects of Henan Province,China(Grant No.15B140004)+2 种基金Henan Science and Technology Development Project,China(Grant No.182102210241)Key Projects of Science and Technology Research of Henan Provincial Department of Education,China(Grant No.18A140014)Industrial Science and Technology Research Projects of Kaifeng,Henan Province,China(Grant No.1501049)
文摘Ceramics usually have irregular grains, cracking, or porosity, which result in their lightproof.Y2Mo3O12 ceramics have more porosity due to the heavy hygroscopicity.Introducing ZnLi to Y2Mo3O12 could form regular grains, reduce cracking and porosity.With increasing the content of ZnLi, the grain shapes self-assembly gradually and then the laser scattering and transmittance improve.The laser scattering property and transmittance of diverging rays become the best in ceramics Y2-x(ZnLi)xMo3O12(x = 1.0 and 1.2) with regular grains and low thermal expansion.The formation mechanism of regular grains is ascribed to the substitutions of Zn^2+ and Li+for Y^3+ in Y2Mo3O12 resulting in the preferential growth.The investigation in laser scattering, transmittance and low thermal expansion behaviors of Y2-x(ZnLi)xMo3O12 could pave a way to weaken the strong-laser attack from the high-power laser weapon and the other.
基金the National Natural Science Foundation of China(Grant No.11604271).
文摘The phase transition behaviors of the shocked water are investigated by employing an optical transmittance in-situ detection system.Based on the light scattering theory and phase transformation kinetics,the phase transition mechanism of the water under multiple shocks is discussed.The experimental data indicate that the evolution of the transmittance of the shocked water can be broadly divided into three stages:relaxation stage,decline stage,and recovery stage.In the early stage of the phase transition,the new phase particles began to form around the quartz/window interface.It should be mentioned that the water/ice phase boundary seems to move toward the liquid region in one experiment of this work.Due to the new phase core being much smaller than the wavelength of the incident light,the transmittance of the sample within the relaxation stage remains steady.The decline stage can be divided into the rapid descent stage and the slow descent stage in this work,which is considered as the different growth rates of the new phase particle under different shock loadings.The recovery stage is attributed to the emergence of the new phase particles which are bigger than the critical value.However,the influence of the size growth and the population growth of the new phase particles on the transmittance restrict each other,which may be responsible for the phenomenon that the transmittance curve does not return to the initial level.
基金Supported by the National Basic Research Program of China under Grant No.2013CB338002the National Natural Science Foundation of China under Grant Nos.61505261,61675235,61605248,11304397
文摘Measurement-device-independent quantum key distribution(MDI-QKD) is immune to detector side channel attacks, which is a crucial security loophole problem in traditional QKD. In order to relax a key assumption that the sources are trusted in MDI-QKD, an MDI-QKD protocol with an untrusted source has been proposed. For the security of MDI-QKD with an untrusted source, imperfections in the practical experiment should also be taken into account. In this paper, we analyze the effects of fluctuations of internal transmittance on the security of a decoy-state MDI-QKD protocol with an untrusted source. Our numerical results show that both the secret key rate and the maximum secure transmission distance decrease when taken fluctuations of internal transmittance into consideration. Especially, they are more sensitive when Charlie's mean photon number per pulse is smaller. Our results emphasize that the stability of correlative optical devices is important for practical implementations.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 60877055 and 60806041)the Innovation Funds for Graduates of Shanghai University,China (Grant No. SHUCX102016)
文摘This paper investigates the photon tunneling and transmittance resonance through a multi-layer structure including a left-handed material（LHM）. An analytical expression for the transmittance in a five-layer structure is given by the analytical transfer matrix method. The transmittance is studied as a function of the refractive index and the width of the LHM layer. The perfect photon tunneling results from the multi-layer structure, especially from the relation between the magnitude of the refractive index and the width of the LHM layer and those of the adjoining layers. Photons may tunnel through a much greater distance in this structure. Transmittance resonance happens, the peaks and valleys appear periodically at the resonance thickness. For an LHM with inherent losses, the perfect transmittance is suppressed.
