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11.
Poly (linoleic acid)-g-poly(methyl methacrylate) (PLiMMA) graft copolymer was synthesized and characterized. PLiMMA graft copolymer was synthesized from polymeric linoleic acid peroxide (PLina) possessing peroxide groups in the main chain by free radical polymerization of methyl methacrylate. Later, PLiMMA was characterized by proton nuclear magnetic resonance (1H NMR), gel permeation chromatography (GPC), thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC) techniques. Furthermore, Au/PLiMMA/n-Si diode was fabricated for the purpose of investigating PLiMMA׳s conformity in diodes. The main electrical characteristics of this diode were investigated using experimental current–voltage (I–V) measurements in dark and at room temperature. Obtained results, such as sufficiently high rectifying ratio of 4.5×104, indicate that PLiMMA is a promising organic material for electronic device applications. 相似文献
12.
In order to protect bolts from corrosion, electroplating such as zinc plating is widely used. However, hydrogen can easily penetrate or diffuse into the vacancies and dislocations between the lattices of bolt steel during electroplating. As the diffused hydrogen defects inside the lattice are in gaseous form, small cracks can easily be produced due to high pressure from the hydrogen gas. In this research, in order to determine the root cause of the fracture in pole fastening screws resulting from hydrogen embrittlement in typical electric motors, additional factors that accelerate hydrogen embrittlement fracture were selectively applied, including a small fillet in the head–shank transition and excessive hardness, and parametric study was performed experimentally. 相似文献
13.
Cold filamentary microplasma (CFM) pretreatment assisted by thermionic emission (TE) is a promising, cold drying technology for agricultural products. Such novel pretreatment method based on local electroporation process in the air gap. Brief theory and treatment mechanism are explained. A fractional factorial design 33 was used to determine the effect of CFM treatment assisted by TE parameters such as pulse frequency (F = 40, 80 and 120 Hz), pretreatment duration (D = 60, 120 and 180 s) and temperature of thermionic source (T = 700, 850 and 1000 °C) on drying time and drying rate of potato samples. Maximal CFM pretreatment effect was observed at frequency of 80 Hz, treatment duration of 120 s and temperature of thermionic source of 1000 °C, and the corresponding drying rate and drying time were 35·10−5 (kg/kg s−1) and 130 min. The use of CFM treatment had minor effects on the main quality characteristics (total sugar and starch content) of potato samples. Fourier-transformed infrared spectroscopy confirmed the absence of any modifications of functional group composition of potato samples after CFM pretreatment. Results indicate that cold pulsed filamentary microplasma can enhance the drying rate and decrease drying time without changes in quality characteristics.Practical applicationsCold filamentary microplasma pretreatment assisted by thermionic emission can improve the efficiency of potato drying. Furthermore, it has potential application for reducing energy consumption in drying. CFM pretreatment could be potentially applied for agricultural products drying. 相似文献
14.
Achieving highly sensitive magnetic sensors by means of Metal-DNA-Metal (MDM) structure is a key issue. DNA, being a genetic information carrier in living cells reveals tunable semiconducting response in the presence of external electric and magnetic fields, which is promising for molecular electronics. The influence of magnetic fields up to 1200 mT on the current–voltage (I–V) behavior of Gold-DNA-Gold (GDG) structure having variable gap sizes from 20–50 μm are reported in this work. These structures were fabricated using UV lithography, DC magnetron sputtering and thermal evaporation techniques. DNA strands were extracted from Boesenbergia rotunda plant via standard protocol. The acquired I–V characteristics display the semiconducting diode nature of DNA in GDG structures. The potential barrier for all the structures exhibit an increasing trend with the increase of externally imposed magnetic field irrespective of variable gap sizes. Furthermore, the potential barrier in GDG junction at higher magnetic field strengths (>1000 mT) is found to be considerably enhanced. This enhancement in the junction barrier height at elevated magnetic fields is attributed to the reduction of carrier mobility and augmentation of resistance. The achieved admirable features of magnetic sensitivity suggest the viability of using these GDG sandwiches as a prospective magnetic sensor. 相似文献
15.
《Optical Fiber Technology》2006,12(3):238-242
We measure the system impacts due to the amplitude of group-delay (GD) ripple in single and cascaded chirped fiber Bragg gratings (CFBGs). Signals with smaller pulse width result in smaller performance variation at the same data rate. A 65-ps peak-to-peak GD ripple induces 0.9, 1.7, and 2.7 dB maximum penalties for 10, 20, and 40-Gb/s, respectively. We also find that cascading gratings with random ripple causes much less degradation than cascading gratings with the same ripple profile. 相似文献
16.
Effects of Neodymium Concentration on Optical Characteristics of Polycrystalline Nd:YAG Laser Materials 总被引:4,自引:0,他引:4
Akio Ikesue Kiichiro Kamata Kunio Yoshida 《Journal of the American Ceramic Society》1996,79(7):1921-1926
A neodymium-doped yttrium-aluminum garnet (Y3 A15 O12 , YAG) (Nd:YAG) ceramic that contained 0.3–4.8 at.% neodymium additives and exhibited nearly the same optical properties as those of a single crystal was fabricated by a solid-state reaction method using high-purity powders. Although the integrated absorption intensity of the 2 H9/2 +4 F5/2 bands simply increased as the neodymium concentration in the YAG ceramics decreased, the fluorescence intensity of the 2.4 at.% Nd:YAG ceramic was the strongest among Nd:YAG ceramics with various neodymium concentrations and a 0.9 at.% Nd:YAG single crystal. An oscillation experiment was performed on a continuous-wave (cw) laser with a diode-laser exciting system using those ceramics and the single crystal. The oscillation threshold and slope efficiency in that analysis were 309 mW and 28%, respectively, for the 1.1 at.% Nd:YAG ceramics and 356 mW and 40%, respectively, for the 2.4 at.% Nd:YAG ceramics. The lasing characteristics of the ceramics in the present work were superior to those of a 0.9 at.% Nd:YAG single crystal that was fabricated by the Czochralski (Cz) method. 相似文献
17.
《Thin solid films》2006,515(2):547-550
Aluminum nitride thin film by RF magnetron sputtering is used to produce antireflection coating on InP. The index of refection variation of aluminum nitride for different thickness at different wavelength in the range of 400 to 1500 nm is investigated using reflection spectroscopy. Subsequent Ar+ ion implantation at 30 keV with different doses on these coated layers has been performed. The morphology of aluminum nitride after ion implantation is characterized using atomic force microscopy AFM. 相似文献
18.
T.Z. Kosc K.L. Marshall Anka Trajkovska-Petkoska Erin Kimball S.D. Jacobs 《Displays》2004,25(5):171-176
Polymer cholesteric liquid crystal (PCLC) flake technology is being developed as an alternative display technology for flexible, reflective particle displays. The motion of PCLC flakes suspended in a host fluid can be controlled with an electric field, creating a way to electrically control the flakes' ability to brightly reflect light that is circularly polarized. The PCLC flake/host fluid dispersion has been successfully microencapsulated both in a polymer matrix and in gelatin micro-capsules. Microencapsulation will not only expand the applications scope of the technology, but also may aid in addressing some potential problem areas that are inherent to many forms of particle display technology. A second important development in PCLC flake technology involves the manufacture of shaped flakes based on soft lithography techniques. The size and shape of a flake impact its reorientation, and uniformly shaped flakes respond in a similar manner. The unique reflective properties of PCLC flakes also provide possible applications in areas such as optics and photonics, switchable ‘smart windows’ or conformal coatings, and information displays such as ‘electronic paper.’ 相似文献
19.
《Optical Materials》2005,27(1):99-102
The spin Hamiltonian parameters g∥, g⊥, A∥ and A⊥ for Er3+ ion in LiYF4 are investigated by using the perturbation formulas of these parameters for a 4f11 ion in tetragonal symmetry. In these formulas, the contributions to the spin Hamiltonian parameters from the second-order perturbation terms and the admixtures of different states are considered. The relevant crystal field parameters are calculated from the superposition model and the local structural parameters of the Y3+ site occupied by impurity Er3+. The theoretical optical spectra within 4I15/2 and 4I13/2 states and the spin Hamiltonian parameters obtained in this work are consistent with the observed values. 相似文献
20.