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11.
Structure modification has been found to tune significantly the transparent-conducting performance, especially mobility and conductivity of hydrogenated Ga-doped ZnO (HGZO) films. The strong correlation between film thickness and mobility of the films is revealed. The mobility increases quickly with increasing the thickness from 350 to 900 nm, and then tends to be saturated at further thicknesses. A higher mobility than 50 cm2/Vs can be achieved, which is an extra-high value for polycrystalline ZnO films deposited by using the sputtering technique. The thickness-dependent mobility originates from scatterings on grain boundaries and dislocation-induced defects controlled by thin-film growth. Based on the Volmer-Weber model, an expansion model is built up to describe the thickness-dependent crystal growth of the HGZO films, especially at the thick films. As a result, the 800 nm-thick HGZO film obtains the highest performance with high mobility of 51.5 cm2/Vs, low resistivity of 5.3 × 10?4 Ωcm, and good transmittance of 83.3 %.  相似文献   
12.
Chemistry and Technology of Fuels and Oils - Application of water flooding technologies in the oilfield causes intensive heterogeneity of the oil reservoir and improper circulation of the injected...  相似文献   
13.
Vu  Hoa T.  Nguyen  Manh B.  Vu  Tan M.  Le  Giang H.  Pham  Trang T. T.  Nguyen  Trinh Duy  Vu  Tuan A. 《Topics in Catalysis》2020,63(11-14):1046-1055
Topics in Catalysis - Nano Fe-BTC/graphene oxide (GO) composites were successfully synthesized by hydrothermal treatment with a microwave-assisted method. Samples were characterized by X-ray...  相似文献   
14.
Ethanol steam reforming (ESR) is one of the potential processes to convert ethanol into valuable products. Hydrogen produced from ESR is considered as green energy for the future and can be an excellent alternative to fossil fuels with the aim of mitigating the greenhouse gas effect. The ESR process has been well studied, using transition metals as catalysts coupled with both acidic and basic oxides as supports. Among various reported transition metals, Ni is an inexpensive material with activity comparable to that of noble metals, showing promising ethanol conversion and hydrogen yields. Additionally, different promoters and supports were utilized to enhance the hydrogen yield and the catalyst stability. This review summarizes and discusses the influences of the supports and promoters of Ni-based catalysts on the ESR process.  相似文献   
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一种单相串联混合电力有源滤波器的研究   总被引:1,自引:0,他引:1  
文中对串联混合电力滤波器抑制谐波的原理进行了分析。为了检测单项系统的谐波电流,提出一种基于虚拟三相法和瞬时无功理论的谐波检测方法,并且对串联滤波逆变器的直流侧电压的控制进行了讨论。仿真结果证明了其有效性。  相似文献   
17.
Crude and refined hazelnut oils from different countries were characterised by major and minor compounds. Fatty acids, triacylglycerides, waxes, sterols, methyl-sterols, terpenic and aliphatic alcohols, tocopherols, tocotrienols and hydrocarbons were identified and quantified by gas chromatography and high-performance liquid chromatography. The levels of these chemical compounds in hazelnut oils together with the equivalent carbon numbers and triacylglyceride carbon numbers, were compared with the results of analyses of samples of other vegetable oils. The statistical procedure of cluster analysis was used to characterise hazelnut oils versus other edible oils.  相似文献   
18.
A 55-year-old woman with primary (granulomatous) angiitis of the central nervous system in association with non-Hodgkin's lymphoma (mucosa-associated lymphoid tissue type) presented with an acute spinal subdural hemorrhage secondary to rupture of one of several fusiform inflammatory aneurysms of the spinal cord radicular arteries. The literature on hemorrhagic complications, aneurysms, and spinal cord involvement in granulomatous angiitis is reviewed. Recognition of granulomatous angiitis is important, as the condition may be responsive to immunosuppressive therapy.  相似文献   
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The dead-end filtration characteristics of the dimorphic yeast Kluyveromyces marxianus var. marxianus (formerly fragilis) NRRLy2415 were investigated for a range of mean cell morphologies, ranging from predominantly yeast-like to predominantly filamentous. Semiautomated image analysis was used to measure the mean cell specific surface area, Sv, and the mean ratio of cell length to equivalent cylindrical diameter, Ldm, in each broth. The method of Ju and Ho (Biotechnol. Bioeng. 1988, 32, 95-99) was used to show that for broths with Ldm values between 1.72 and 10.03, the voidage of cell pellets formed by centrifugation increased with increasing Ldm. In the pressure range 30-180 kPa, the specific filter cake resistance, alpha, was found to be related to pressure, DeltaP, through the equation alpha = alpha0(1 + kcDeltaP). The dependence of alpha0/Sv2 on Ldm was found to be qualitatively consistent with the pellet voidage data and the Carman-Kozeny equation. Considerably better agreement with the experimental data was obtained when the Kozeny constant, K, was treated as variable and related to Ldm through the equation K = 4.83 + 7.08 log10 Ldm. The cake compressibility constant, kc, was found to increase with increasing Ldm, a phenomenon consistent with the wide range of voidages that can be displayed by beds of long cylinders.  相似文献   
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