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Electrical and interface state properties of the borontrifluoride doped poly(3‐aminoacetophenone)/p‐Si junction have been investigated by current‐voltage and impedance spectroscopy methods. Al/p‐Si/P3APBF3/Aldiode indicates a nonideal behavior with electrical parameters (n = 3.53, ?B = 0.82 eV, and Rs = 1.48 kΩ), which result from the interfacial layer, series resistance, and resistance of the organic semiconductor. The obtained barrier height value of the Al/p‐Si/P3APBF3/Aldiode is higher than that of the conventional Al/p‐Si (?B = 0.58 eV) Schottky diode. The interface state density of the diode was of the order of 1.05× 1012 eV?1 cm?2. It is evaluated that the barrier height and interface state density values of the diode are modified using the boron trifluoride doped poly (3‐aminoacetophenone) organic semiconductor. POLYM. ENG. SCI., 2010. © 2009 Society of Plastics Engineers 相似文献
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The throughput performance model and the state equation model are alternative analytical approaches for determining the proportion of dual versus single command crane cycles in automated storage and retrieval systems that utilize opportunistic interleaving. The different assumptions underlying these models result in biases in the estimation of expected crane cycle times. The magnitude of the biases is investigated to assess whether the use of the older, less computationally efficient state equation model is still warranted in practical conceptualizing situations. The results suggest that the TP model is a dominating alternative for AS/RS conceptualizing applications. 相似文献
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The pentacene thin film transistor was fabricated on a SiO2/Si substrate by thermal evaporated method at room temperature. Electrical characteristics of the pentacene transistor subjected to a UV light excitation at a wavelength of 365 nm were analyzed. A significant increase in the drain current of the pentacene thin film transistor under a UV excitation of 365 nm is observed with a maximum photosensitivity of 4.51 in the depletion regime. It is concluded that the pentacene thin film transistor can be used in UV photo-detecting devices. 相似文献
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Moisture sorption isotherms of grape pestil and foamed grape pestil were determined using the static gravimetric method at 10, 20 and 30 degrees C. The overall shape of the curves was typical of sugar-rich materials. The effect of temperature on moisture content in the lower aw range was not significant (P > 0.05). Four models, namely the Brunauer, Emmet and Teller (BET), the Guggenheim, Anderson and DeBoer (GAB) the Halsey and the Oswin, were evaluated to determine the best fit for the experimental data. The BET and GAB models fitted well the data of the samples in the temperature and water activity range studied. The Clausius-Clapeyron equation was used to evaluate the isosteric heats of sorption. 相似文献
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Fahrettin Yakuphanoglu 《Synthetic Metals》2010,160(13-14):1551-1555
Electrical and photovoltaic properties of a metal–semiconductor–insulator–polymer–metal diode were investigated. The n-Si/SiO2/MEH-PPV/Al diode shows a rectifying behavior with the rectification ratio of 2.22 × 105 at ±5 V and exhibits a non-ideal behavior due to the series resistance and oxide-organic layers. The organic semiconductor makes a contribution to the I–V characteristics of the diode and the trap-charge limited space charge and space charge limited current mechanisms were observed for the diode. The current–voltage characteristics of the n-Si/SiO2/MEH-PPV/Al diode under different illumination intensities give an open circuit voltage (Voc) along with a short circuit current (Isc). This suggests that the n-Si/SiO2/MEH-PPV/Al diode is a photovoltaic device with Voc = 0.456 V and Jsc = 7.89 × 10?8 A/cm2 values under 100 mW/cm2 illumination intensity. The photoconductivity mechanism of the diode is controlled by monomolecular recombination. The interface state density Dit values with time constant τit of the diode under dark and illumination conditions were found to be 2.53 × 1010 eV?1 cm?2 with 5.09 × 10?5 s and 2.50 × 1010 eV?1 cm?2 with 8.27 × 10?5 s, respectively. The obtained results indicate that the n-Si/SiO2/MEH-PPV/Al diode is a photo-sensitive diode. 相似文献
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The preparation and physical properties of some ionomers have been investigated. The addition of CH3I significantly improved the conductivity of the ionomers. At room temperature, the highest ionic conductivity value was found to be 4.93 10−8 S cm−1 in the I4 ionomer. The conductivity data do not obey the Arrhenius law and the non‐linearity indicates ionic transport. The alternating current conductivity parameters and dielectric constants of the ionomers were determined. Copyright © 2005 Society of Chemical Industry 相似文献
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BACKGROUND: Electrical conductivity, photoconductivity, voltage‐controlled negative resistance and thermal properties of copolymers of 2‐acrylamido‐2‐methyl‐1‐propanesulfonic acid and maleic acid were investigated in order to obtain new organic semiconductors. RESULTS: The room temperature conductivity of three different copolymers was found to be in the range 1.28 × 10?8 ? 1.20 × 10?7 S cm?1. The dark‐ and photo‐current‐voltage characteristics indicate that the copolymers exhibit voltage‐controlled differential negative resistance behaviour. The electrical conductivity of the polymers increases by photo‐illumination, suggesting that the polymers exhibit photoconductivity. The width of the exponential tail in the forbidden band gap of the three polymers was determined via the transient photocurrent technique and E0 values were in the range 34.4–36.49 meV. CONCLUSION: The results suggest that the copolymers could be used as organic semiconductor materials. Copyright © 2007 Society of Chemical Industry 相似文献
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Nalan Gokoglu Osman Kadir Topuz Mehmet Gokoglu Fahrettin Gokhun Tokay 《Sensing and Instrumentation for Food Quality and Safety》2017,11(4):1699-1705
The aim of this study was to investigate the effects of tumbling on the physicochemical and textural characteristics of squid (Loligo vulgaris), octopus (Octopus vulgaris) and cuttlefish (Sepia officinalis) muscles. Before tumbling the cephalopod samples were placed in plastic bags and 0.5 M NaCl was added. Tumbling process was performed continuously in three different tumbling times (2, 4, and 6 h). The results of the analyses showed that tumbling affected the physicochemical properties of cephalopod muscles. The increase in the time of tumbling resulted in the tenderness of the cephalopod muscles. The total soluble protein, the total free amino acid, and pH values increased with the increase of the tumbling time. The water holding capacity decreased and the cooking loss increased. The squid and octopus hardness and shear force values decreased after tumbling, according to instrumental and sensorial texture measurements. As a result, tumbling was found to be an effective method for tenderizing of squid and octopus muscle, but not for cuttlefish. 相似文献