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941.
In this article, 3-Hexyl thiophene (3HTh) monomer was electrocoated on carbon fiber micro electrode (CFME) to study electrochemical impedance spectroscopic (EIS) analysis. Poly(3HTh)/CFME is characterized by Cyclic voltammetry (CV), Fourier transform infrared reflectance-attenuated total reflection spectroscopy (FTIR-ATR), Scanning electron microscopy-Energy Dispersive X-ray analysis (SEM-EDX), and electrochemical impedance spectroscopy (EIS). The effects of different monomer concentrations (0.5, 1.0 and 1.5 mM) on polymer were reported in 0.1 M tetraethyl ammonium tetrafluoroborate (TEABF4)/acetonitrile (ACN) solution. The highest low frequency capacitance (CLF = 1.394 mF cm?2) was obtained for [3HTh]0 = 0.5 mM. The equivalent circuit model of R(QR(CR)(RW))(CR) was examined for polymer/electrolyte system. 相似文献
942.
M. Murat Karaoglu 《International Journal of Food Properties》2013,16(3):583-596
Part-baked rye bread with and without Ca-propionate (0.2 g/100 flour) were baked for 10, 15, 20 minutes at 230°C and stored at refrigerator temperature (4°C) for 10, 20, 30 days then second-baked for 5, 10, 15 minutes at the same temperature to give an oven-fresh end product. The effect of antimicrobial additive (Ca-propionate), part-baking, storage in refrigerator and rebaking on quality parameters such as yield of volume and crumb softness, water activity and pasting properties of rye bread crumb was evaluated. Addition of Ca-propionate increased bump area, while yield of volume and softness values of rye bread crumb decreased. The increase in initial baking time caused a decrease in the pasting temperature, water activity, and softness value and an increase in the bump area and viscosity of the rebaked bread crumb. Bump area and pasting temperature of rebaked rye bread crumb increased with longer (intermediate storage) time, while viscosity, yield of volume, water activity, and softness values decreased. A strong negative correlation was observed between pasting temperature and other parameters, which are bump area, peak viscosity, holding end viscosity, cooling end viscosity, and softness value for rye bread that was rebaked after part-baked and storing at refrigerator temperature. The re-baking rye bread after part-baking for 10 and 15 minutes and storage for 7, 14, and 21 days at refrigerator temperature gave softer crumb than the control group. 相似文献
943.
M. Murat Karaoglu 《International Journal of Food Properties》2013,16(4):609-622
In this investigation, the white pan breads were part-baked for 10, 15, 20 minutes at 230°C with and without calcium propionate (0.2%), were stored at room temperature (20°C) for 3, 5, 7 days wrapped with two polyethylene bags. After storage, baking time of part-baked breads was completed to the baking time of control breads (25 minutes). Breads were subjected to softness analysis and pasting properties of bread crumb were determined using the Brabender Amylograph. Addition of Ca-propionate decreased softness value of crumb of bread rebaked after part-baked, while the peak, holding end and cooling end viscosities increased. The increase in initial baking time resulted in a decrease in the pasting temperature and softness value and an increase in the bump area and viscosity of the rebaked bread crumb. Bump area, water activity, softness value and peak, holding end and cooling end viscosities of crumb of the rebaked bread after part-baking decreased with longer (intermediate storage) time. Peak viscosity and water activity significantly correlated with softness of bread crumb rebaked following part-baking and storage at room temperature. Rebaking bread for 10 and 15 minutes after storage of 3 and 7 days at room temperature resulted in softer crumb than the control group. 相似文献
944.
本文介绍了用~(60)Coγ辐射引发聚合合成纯度较高的聚甲基丙烯酸三丁基锡酯(PTBTM),并对它的辐射聚合反应动力学进行了研究。结果表明TBTM浓度与聚合反应速率R_P之间的关系为R_P=K_P[TBTM]~2;辐射剂量率I与反应速率之间的关系为R_P=K_PI~(0.66);辐射聚合反应的表观活化能E_n为3.12J/mol。本文还对聚合反应的机制进行了探讨。 相似文献
945.
946.
In this paper a mode II fracture testing method has been developed for wood from analytical, experimental and numerical investigations. Analytical results obtained by other researchers showed that the specimen geometry and loading type used for the proposed mode II testing method results in only mode II stress intensity and no mode I stress intensity at the crack tip. Experiments have been carried out to determine mode II fracture toughness K
IIC and fracture energy G
IIF from the test data collected from both spruce (pice abies) and poplar (populus nigra) specimens. It was found that there existed a very good relation between fracture toughness KIIC and fracture energy G
IIF when the influence of orthotropic stiffness E
II
* in mode II was taken into account. It verified that for this mode II testing method the formula of LEFM can be employed for calculating mode II fracture toughness even for highly orthotropic materials like wood. In the numerical studies for the tested spruce specimen, the crack propagation process, stress and strain fields in front of crack tips and the stress distributions along the ligament have been investigated in detail. It can be seen that the simulated crack propagating process along the ligament is a typical shear cracking pattern and the development of cracks along the ligament is due to shear stress concentrations at the crack tips of the specimen. It has been shown that this mode II fracture testing method is suitable for measuring mode II fracture toughness K
IIC for highly orthotropic materials like wood. 相似文献
947.
Utku Celik M. Sharma G. Saber E. Murat Tekalp A. 《IEEE transactions on image processing》2002,11(6):585-595
Several fragile watermarking schemes presented in the literature are either vulnerable to vector quantization (VQ) counterfeiting attacks or sacrifice localization accuracy to improve security. Using a hierarchical structure, we propose a method that thwarts the VQ attack while sustaining the superior localization properties of blockwise independent watermarking methods. In particular, we propose dividing the image into blocks in a multilevel hierarchy and calculating block signatures in this hierarchy. While signatures of small blocks on the lowest level of the hierarchy ensure superior accuracy of tamper localization, higher level block signatures provide increasing resistance to VQ attacks. At the top level, a signature calculated using the whole image completely thwarts the counterfeiting attack. Moreover, "sliding window" searches through the hierarchy enable the verification of untampered regions after an image has been cropped. We provide experimental results to demonstrate the effectiveness of our method. 相似文献
948.
Measurements were made on the longitudinal and transverse strain of sea-ice beams loaded in flexure. The specimens were tested with stress rates varying from 10 to 600 kPa s?1 and temperatures ranging from ?5°C to ?40°C. Under these conditions, the effective strain ratio μ increases with increasing temperature and decreasing stress rate. The strong influence of the stress rate, σ, suggests an empirical law of the form: μ = 0.24 where σ is the stress rate (kPa s?1), is a unit stress ratio (1 kPa s?1) and μD is a dynamic value of Poisson's rate which depends on the temperature. 相似文献
949.
甲基丙烯酸三丁基锡酯与甲基丙烯酸甲酯的辐射共聚 总被引:1,自引:0,他引:1
甲基丙烯酸三丁基锡酯与甲基丙烯酸甲酯的共聚物是一种优良的自抛光防污漆的基料。我们研究了用~(60)Coγ辐射在室温进行合成的新方法,并且对其共聚反应的动力学过程进行了探讨,由反应速率与辐射剂量率的关系R_P=K_PI~(0.52),共聚反应中两种单体的竞聚率小于1,以及表观活化能仅为1.29×10~4J/mol,初步确认该共聚反应是自由基反应机制。 相似文献
950.
A large sea water desalination plant, using the multi-effect process at high temperature has been described and a comparison is given with the other distillation processes.The multi-effect plant is easily adaptable in a wide range of operating conditions. It has a low total energy consumption (8.75 KWh per m3 produced (expressed as electrical energy). A high GOR is obtained (12.4). Compared with a MSF of the same production capacity, the investment costs are smaller. This leads to a substantial decrease in cost of the produced water. The technology of horizontal sprayed tubes is a proven one and has been executed more than a hundred times on small and medium units. 相似文献