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1.
研究了经三种不同类型的透明剂处理后的在体人皮组织在波长为400~1 000 nm范围内随时间变化反射光谱特性的变化及各组于580 nm处分别在0~60 min时间段各组反射光谱的改变程度.实验采用USB-4000光纤光谱仪分别获取经丙三醇、葡萄糖及丙二醇处理在体人皮肤组织前后的在0,10,20,30,40,50和60 ...  相似文献   

2.
The purpose of study is to quantify and compare diffusion of propylene glycol, glucose, glycerol in the human skin in vivo noninvasively. Optical coherence tomography (OCT) was utilized in the functional imaging of optical cleaning agents for monitoring and quantifying the permeability coefficients (PCs) of them. Our experiments showed that the permeability coefficient of 40% propylene glycol from different subjects was averaged and found to be (2.52 ± 0.02) × 10−6 cm/s, the permeability coefficient of 40% glucose was (1.94 ± 0.05) × 10−6 cm/s, and the permeability coefficient of 40% glycerol was (1.82 ± 0.04) × 10−6 cm/s. The results indicated that the diffusion of propylene glycol solutions was faster than that of glucose solution, and the diffusion of glucose solutions was faster than that of glycerol solutions. The dependence of the permeability on the different hyperosmotic analytes could potentially be used in various basic science and clinical fields, such as optical clearing of tissues and cells as well as in clinical pharmacology.  相似文献   

3.
Daeil Kim 《Optics Communications》2010,283(9):1792-1794
Au-intermediate TiO2/Au/TiO2 (TAT) multilayer films were deposited by RF magnetron sputtering onto glass substrates. Changes in the optical and electrical properties of the films were investigated with respect to the thickness of the Au interlayer.The observed optical and electrical properties were dependent on the thickness of the Au interlayer. The resistivity decreased to 3.3 × 10−4 Ω cm for TiO2 films with a 20 nm-thick Au interlayer and the optical transmittance was also influenced by the Au interlayer. Although optical transmittance deteriorated as Au thickness increased, TiO2 films with a 5 nm-thick Au interlayer showed a relatively high optical transmittance of 80% at a wavelength of 550 nm. In addition, since a TAT film with a 5 nm-thick Au interlayer showed a relatively high work function value, it is an alternative candidate for use as a transparent anode in OLEDs and flat panel displays.  相似文献   

4.
Iron oxide thin films were prepared by spray pyrolysis technique (SPT) at various substrate temperatures (Tsub) and different deposition time. X-ray diffraction (XRD) analysis showed that, at Tsub ≥ 350 °C, a single phase of α-Fe2O3 film is formed which has the rhombohedral structure. Moreover, the crystallinity was improved by increasing Tsub. The effect of Tsub as well as deposition time on the optical dispersion of these films has been investigated. The optical transmittance and reflectance measurements were performed by using spectrophotometer in the wavelength range from 300 to 2500 nm. The refractive index was determined by using Murmann's exact equation. It was observed that, the refractive index increased with increasing in both the Tsub and film thickness. The optical dispersion parameters have been evaluated and analyzed by using Wemple-Didomenico equation. The obtained results showed that, the dielectric properties have weak dependencies of growth temperature and film thickness. At Tsub ≥ 350 °C, the average values of oscillator energy, Eo and dispersion energy, Ed were found to be 5.96 and 34.08 eV. While at different thickness, the average values of dispersion energies were found to be 3.93 and 17.08 eV. Also, the average values of oscillator strength So and single resonant frequency ωo were estimated 10.78 × 1013 m−2 and 5.99 × 1015 Hz, while at different thickness were evaluating 4.81 × 1013 m−2 and 6.11 × 1015 Hz. Furthermore, the optical parameters such as wavelength of single oscillator λo, plasma frequency ωp, and dielectric constant ? have been evaluated. The carrier concentration Nopt by using Drud's theory was obtained the range of 5.07 × 1025 m−3 to 1.04 × 1026 m−3.  相似文献   

5.
The optical trapping characteristics of highly focused higher-order radially polarized beams (R-TEMp1*) acting on a Rayleigh particle are studied theoretically. Numerical results show that as the order p of beam increases and the numerical aperture NAo of the objective decreases, the axial trap distance increases but the trap depth and maximum restoring force decreases. In a limit of NAo = 1, three higher-order R-TEMp1* beams of p = 1, 2, 3, like the fundamental lowest-order radially polarized beam of p = 0, can three-dimensionally trap a particle to the focus but the axial trap stiffness decreases with the increase of p. When NAo = 0.95, the focus is still a stable trap point for the two beams of p = 0 and 1 but it becomes an unstable trap point for the two beams of p = 2 and 3. The trap stability is also discussed for higher-order radially polarized beam illumination.  相似文献   

6.
A high-quality ZnNb2O6 single-crystal grown by optical floating zone method has been used as a research prototype to analyze the optoelectronic parameters by measuring the absorption coefficient and transmittance spectra along the b-axis from 200 nm to 1000 nm at room temperature. The optical interband transitions of ZnNb2O6 have been determined as a direct transition with a band gap of 3.84 eV. The refractive index, extinction coefficient, and real and imaginary parts of the complex dielectric constants as functions of the wavelength for ZnNb2O6 crystal are obtained from the measured absorption coefficients and transmittance spectra. In the Urbach tail of 3.16–3.60 eV, the validity of the Cauchy–Sellmeier equation has also been evaluated. Using the single effective oscillator model, the oscillator energy Eo is found to be 4.77 eV. The dispersion energy Ed is 26.88 eV and ZnNb2O6 crystal takes an ionic value.  相似文献   

7.
Transparent conducting indium oxide (In2O3) thin films have been prepared on glass substrates by the simple sol-gel-spin coating technique. These films have been characterized by X-ray diffraction, resistivity and Hall effect measurements, optical transmission, scanning electron microscopy and atomic force microscopy for their structural, electrical, optical and morphological properties. The influence of spin parameters, number of coating, process temperature on the quality of In2O3 films are studied. In the operating range of deposition, 400-475 °C, all the films showed predominant (2 2 2) orientation. Films deposited at optimum process conditions exhibited a resistivity of 2×10−2 Ω cm along with the average transmittance of about 80% in the visible spectral range (400-700 nm).  相似文献   

8.
This study investigated the optical and electrical properties of Nb-doped TiO2 thin films prepared by pulsed laser deposition (PLD). The PLD conditions were optimized to fabricate Nb-doped TiO2 thin films with an improved electrical conductivity and crystalline structure. XRD analyses revealed that the deposition at room temperature in 0.92 Pa O2 was suitable to produce anatase-type TiO2. A Nb-doped TiO2 thin film attained a resistivity as low as 6.7 × 10−4 Ω cm after annealing at 350 °C in vacuum (<10−5 Pa), thereby maintaining the transmittance as high as 60% in the UV-vis region.  相似文献   

9.
Iron oxide thin films were prepared by spray pyrolysis technique onto glass substrates from iron chloride solution. They were characterized by X-ray diffractometry (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and (UV-vis) spectroscopy. The films deposited at Ts ≤ 450 °C were amorphous; while those produced at Tsub = 500 °C were polycrystalline α-Fe2O3 with a preferential orientation along the (1 0 4) direction. By observing scanning electron microscopy (SEM), it was seen that iron oxide films were relatively homogeneous uniform and had a good adherence to the glass substrates. The grain size was found (by RX) between 19 and 25 nm. The composition of these films was examined by X-ray photoelectron spectroscopy and electron probe microanalysis (EPMA). These films exhibited also a transmittance value about 80% in the visible and infrared range. The cyclic voltammetry study showed that the films of Fe2O3 deposited on ITO pre-coated glass substrates were capable of charge insertion/extraction when immersed in an electrolyte of propylene carbonate (PC) with 0.5 M LiCLO4.  相似文献   

10.
The method for measuring second-order nonlinear optical coefficients based on well-known Z-scan is presented. The influence of linear absorption coefficients on normalized transmittance is discussed. Using this method, we obtained the second-order nonlinear coefficient d31(5%MgO:LiNbO3) = 4.5 × 10−12 m/v at 1064 nm, which agrees well with theoretical calculations and previous well-known values.  相似文献   

11.
Titanium oxynitride films have been deposited on glass substrates by reactive RF magnetron sputtering of titanium target. The influence of oxygen partial pressure in N2 + Ar and N2 + He mixtures was examined on structural and optical properties of titanium oxynitride films. The prepared samples were characterized by X-ray diffraction, EDS, surface profilometer, AFM and contact angle measurement system. With increase in oxygen partial pressure, the grain size decreases from ∼70 nm to ∼50 nm in N2 + Ar mixture, while from ∼60 nm to ∼37 nm in N2 + He mixture. The thickness calculated from optical transmission data and surface profilometer is in good agreement with each other. The deposited samples are hydrophobic by nature and the contact angle was found to decrease with increase in oxygen partial pressure. Samples prepared in oxygen partial pressure ≥5.5% show transmittance of about 97% in the visible region of the spectrum in both N2 + Ar and N2 + He mixtures. The atomic mass of the sputtering gas (Ar and He) significantly affects the primary crystallite size, orientation as well as band gap. We were able to relate the better crystallisation of titanium atoms with low partial pressure of oxygen when films are deposited in helium instead of argon due to Penning ionization.  相似文献   

12.
The effect of the dopants of Cr and V on the optoelectronic properties of AZO thin film by pulsed DC magnetron sputtering has been investigated. We also use HCl and KOH solutions to conduct the chemical stability of AZO:Cr:V thin film. The experimental results show that the optimum AZO optoelectronic properties without Cr and V doping obtain the resistivity of 9.87 × 10−4 Ω cm, optical transmittance of 84% and surface roughness rms value of 2.6 nm. The chemical stability of AZO will increase after Cr and V doping. Under the added V = 0.19 wt.%, Cr = 0.56 wt.%, AZO:Cr:V thin film showed 52% increased chemical stability and 128% decrease in surface roughness after etching (the resistivity was 3.62 × 10−3 Ω cm and optical transmittance 81%). From the experimental results, the higher resistivity obtained after KOH etching compared with after HCl etching. The reason is that the Zn/Al ratio will reduce after etching and cause the AZO film carrier density to reduce as well. However, the optical transmittance obtained after KOH etching will be higher than that after HCl etching. This is because that a better surface roughness after KOH etching obtained than after HCl etching.  相似文献   

13.
Microwave-assisted synthesis is a novel method used to synthesize CdMoO4 nanoparticles in propylene glycol. The effects of reaction time and microwave power on phase, morphologies, and optical properties of CdMoO4 nanoparticles were studied, using X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), and UV-visible spectroscopy. The present analyses proved that these crystalline powders were scheelite-type tetragonal structured CdMoO4, with the crystallite size of 14-20 nm, and 4.51-4.73 eV band gaps, controlled by the synthetic conditions.  相似文献   

14.
ZnO and Al-doped ZnO(ZAO) thin films have been prepared on glass substrates by direct current (dc) magnetron sputtering from 99.99% pure Zn metallic and ZnO:3 wt%Al2O3 ceramic targets, the effects of substrate temperature on the crystallization behavior and optical properties of the films have been studied. It shows that the surface morphologies of ZAO films exhibit difference from that of ZnO films, while their preferential crystalline growth orientation revealed by X-ray diffraction remains always the (0 0 2). The optical transmittance and photoluminescence (PL) spectra of both ZnO and ZAO films are obviously influenced by the substrate temperature. All films exhibit a transmittance higher than 86% in the visible region, while the optical transmittance of ZAO films is slightly smaller than that of ZnO films. More significantly, Al-doping leads to a larger optical band gap (Eg) of the films. It is found from the PL measurement that near-band-edge (NBE) emission and deep-level (DL) emission are observed in pure ZnO thin films. However, when Al was doped into thin films, the DL emission of the thin films is depressed. As the substrate temperature increases, the peak of NBE emission has a blueshift to region of higher photon energy, which shows a trend similar to the Eg in optical transmittance measurement.  相似文献   

15.
Al-doped ZnO (AZO, ZnO:Al2O3 = 98:2 wt%) films are deposited on different substrates by an RF magnetron sputtering and subsequently annealed at three different conditions to investigate the microstructural, electrical, and optical properties. X-ray diffraction and scanning electron microscope results show that all the samples are polycrystalline and the samples rapid-thermal-annealed at 900 °C in an N2 ambient contain larger grains compared to the furnace-annealed samples. It is shown that the sample deposited at room temperature on the sapphire gives a resistivity of 5.57 × 10−4 Ω cm when furnace-annealed at 500 °C in a mixture of N2:H2 (9:1). It is also shown that the Hall mobility vs. carrier concentration (μ-n) relation is divided into two groups, depending on the annealing conditions, namely, either rapid-thermal annealing or furnace annealing. The relations are described in terms of either grain boundary scattering or ionized impurity scattering mechanism. In addition, the samples produce fairly high transmittance of 91-96.99% across the wavelength region of 400-1100 nm. The optical bandgaps of the samples increase with increasing carrier concentration.  相似文献   

16.
Pure VO2 and VO2-WO3 composite thin films were grown on quartz substrate by pulsed laser deposition (PLD) technique. The influence of varying WO3 molar concentration in the range from x = 0.0 to x = 0.4 on structural, electrical and optical properties of VO2-WO3 nanocomposite thin films has been systematically investigated. X-ray diffraction studies reveal the single crystalline monoclinic VO2 phase (m-VO2) up to 10% of WO3 content whereas both m-VO2 as well as h-WO3 (hexagonal WO3) phases were present at higher WO3 content (0.2 ≤ x ≤ 0.4). Optical transmittance spectra of the films showed blue shift in the absorption edge with increase in WO3 content. Temperature dependence of resistivity (R-T) measurements indicates significant variation in metal-insulator transition temperature, width of the hysteresis, and shape of the hysteresis curve. Cyclic Voltammetry measurements were performed on VO2-WO3 thin films. A direct correlation between V/W ratio and structure-property relationship was established. The present investigations reveal that doping of WO3 in VO2 is effective to increase the optical transmittance and to reduce the semiconductor to metal phase transition temperature close to room temperature.  相似文献   

17.
Well-crystallized 250 nm-thick SrTiO3 thin films on fused-quartz substrate were prepared by pulsed laser deposition. The band-gap of SrTiO3 thin film by transmittance spectra is equal to 3.50 eV, larger than 3.22 eV for the bulk crystal. The nonlinear optical properties of the films were examined with picosecond pulses at 1.064 μm excitation. A large two-photon absorption (TPA) with absorption coefficient of 87.7 cm/GW was obtained, larger than 51.7 cm/GW for BaTiO3 thin films. The nonlinear refractive index n2 is equal to 5.7×10−10 esu with a negative sign, larger than 0.267×10−11 esu for bulk SrTiO3. The large TPA is attributed to intermediate energy levels introduced by the grain boundaries, and the optical limiting behaviors stemming from both TPA and negative nonlinear refraction were also discussed.  相似文献   

18.
Transparent conductive SnO2:F thin films with textured surfaces were fabricated on soda-lime-silica glass substrates by spray pyrolysis. Structure, morphology, optical and electrical properties of the films were investigated. Results show that the film structure, morphology, haze, transmittance and sheet resistance are dependent on the substrate temperature and film thickness. An optimal 810 nm-thick SnO2:F film with textured surface deposited at 520 °C exhibits polycrystalline rutile tetragonal structure with a (2 0 0) orientation. The sheet resistance, average transmittance in visible region, and haze of this film were 8 Ω/□, 80.04% and 11.07%, respectively, which are suitable for the electrode used in the hydrogenated amorphous silicon solar cells.  相似文献   

19.
Glasses with compositions 25Li2O-(75−x)Bi2O3-x B2O3, with 0?x?30 mol%, have been prepared using the melt quenching technique. The density and the molar volume have been determined. IR spectroscopy is used as a structural probe of the nearest neighbor environment in the glass network. The optical transmittance and reflectance spectrum of the glasses have been recorded in the wavelength range 400-1100 nm. The values of the optical band gap Egopt for indirect transition and refractive index have been determined for 0?x?30 mol%. The average electronic polarizability of the oxide ion αo2− and the optical basicity have been estimated from the calculated values of the refractive indices. Variations in the different physical parameters such as the density, molar volume, optical band gap, refractive index, average electronic polarizability of the oxide ion and optical basicity with B2O3 content have been analyzed and discussed in terms of the changes in the glass structure.  相似文献   

20.
Transparent semiconducting copper iodide (CuI) films were prepared by XeCl Excimer laser and their characteristics are investigated. These films exhibited optical transmittance over 80% in the wavelength range from 400 to 900 nm and minimum resistivity of about 2 kΩ cm−1. The optical absorption of the these films shows a remarkable blue shift compared to that of polycrystalline of CuI, which can be explained from the viewpoint formation of ultra fine of CuI grains. The titanium dioxide (TiO2) films have been prepared by sol-gel method. The properties of pulsed laser deposited CuI and TiO2 films in power output of n-TiO2|dye|p-CuI cells is studied. An efficient charge generation is observed through the illumination of TiO2 layer of the fabricated n-TiO2|dye|p-CuI solid state photovoltaic solar cells. From the current-voltage characteristics, the fill factor and power conversion efficiency were about of 45 and 3%, respectively. The maximum photo-current of about 12.5 mA/cm2 and photo-voltage of 475 mV under AM 1.5 conditions were obtained for the n-TiO2|dye|p-CuI solid states photovoltaic solar cells with good reproducibility. Adsorbed dye molecules to the TiO2 surface act as a relay, especially under illumination through TiO2 layer in the wave range region of 300-400 nm.  相似文献   

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