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51.
52.
In this paper a performance based comparison of top and bottom contact organic thin film transistor (OTFT) device structures, using two dimensional numerical simulations has been carried out. In addition to this, investigations pertaining to the estimation of contact resistance in these OTFTs were also performed. To estimate contact resistance the conventional transmission line method and modified transmission line method (M-TLM) were respectively invoked. Our simulation results clearly indicate that the latter is more accurate in the estimation of contact resistance compared to the conventional method. Furthermore, the M-TLM was used to estimate the gate voltage and film thickness dependence of the contact resistance for the two device structures. The observed results have been explained on the basis of the significantly lowered area of carrier injection and extraction regions, at the source/channel and channel/drain interface respectively, in bottom contact transistor that lead to its inferior performance over the top contact transistor. 相似文献
53.
Stereological measurements were performed to characterize the indentation crack path in a cubic zirconia-10 vol% alumina (c-ZrO2 -10 vol% Al2 O3 ) composite. Cracks were generated using Vickers indentation, and the crack propagation behavior was characterized as a function of the indentation loading/unloading rates. Cracks that were produced by Vickers indentation formed at higher crack velocities as the loading/unloading rates increased. The amount of contact between the crack and the Al2 O3 particles increased as the indentation rate decreased. The total number of crack-particle interactions per unit crack length also increased as the indentation rate decreased, because of an increase in the number of particles that were fractured per unit crack length, whereas the number of particles that were debonded remained relatively constant as the indentation rate changed. These results suggest that residual thermal mismatch stresses have predominant control of the crack path at lower crack velocities (low indentation loading/unloading rate), whereas elastic mismatch stresses predominate at higher crack velocities (high indentation loading/unloading rate). 相似文献
54.
Snehalkumar Parmar Kamal K. Pant Mathew John Kishore Kumar Shivanand M. Pai Shalini Gupta Bharat L. Newalkar 《Journal of Porous Materials》2014,21(5):849-857
Hydroisomerization of n-hexadecane is performed over ZSM-12 framework having tailored Brønsted acidity to investigate the effect in terms of product selectivity and yield. For this purpose, pure phase of ZSM-12 (bulk molar ratio Si/Al ~ 60) has been synthesized using TEABr as a structure directing agent. The framework Brønsted acidity is tailored with group II elements (M) viz. Ca, Ba and Mg, by means of ion-exchange method. The samples so prepared have been characterized for phase purity, textural parameters, morphology by employing powder X-ray diffraction, nitrogen adsorption–desorption isotherm measurement at 77 K, and scanning electron microscopy technique, respectively. Similarly, % metal exchange is estimated using inductively coupled plasma technique. The quantification of Brønsted acidity for H+–M++–ZSM-12 samples has been estimated by means of ammonia temperature programmed desorption (NH3-TPD) and Fourier transform infrared spectroscopy of ammonia (NH3-FTIR). The well characterized H+–M++–ZSM-12 samples were loaded with Platinum (Pt, 0.5 wt%) and subjected to hydroisomerization of n-hexadecane using an up-flow fixed bed reactor to verify the effect of process parameters like temperature and WHSV. Pt/H+–Ba2+–ZSM-12 with tailored Brønsted acidity in the range of about 25 % demonstrated the optimum performance among all the catalysts with an increased isomer selectivity and yield (89.2 and 80.3 %, respectively) by about 4 wt% at a conversion level of about 90 % compared to Pt/H+–ZSM-12 framework at 568 K. Such enhancement in isomer selectivity and yield is found to be significant from commercial application point of view. Based on the obtained trend, the potential benefits of implementation of Pt/H+–Ba2+–ZSM-12 (bulk molar ratio Si/Al ~ 60) framework for cold flow property improvement of ‘bio-ATF’ have been envisaged. 相似文献
55.
Bharat Ugale C. M. Nagaraja 《Journal of Inorganic and Organometallic Polymers and Materials》2014,24(6):1032-1037
A new metal–organic framework of Zn(II) ion, [Zn(muco)(bipy)·2H2O] (where, muco = trans, trans-muconate dianion, bipy = 4,4′-bipyridine) has been synthesized by solvothermal reaction of Zn(II) ion, muco ligand and bipy spacer. X-ray structure determination reveals that compound 1 has a 3D diamondoid (dia) framework with novel fivefold interpenetrating nets. Topological analysis shows the presence of 4-connected Zn(II) nodes with {66} topology. Thermal analysis reveals that the compound is stable up to 340 °C. Photoluminescence study shows the emission of 1 owing to the presence of muco ligand and the intensity of luminescence emission is higher than that of free muco ligand. 相似文献
56.
Membrane separation methods such as electrodialysis (ED) can reduce the volume load on evaporators by facilitating further concentration of rejects from reverse osmosis (RO) plants. ED studies were carried out on a bench-scale system using five membrane cell pairs to obtain a textile effluent concentrate containing approximately 6 times the quantity of salts present in the RO reject. The limiting current densities were determined to be in the range 2.15–3.35 amp/m2 for feed flow rates varying from 18 to 108 L/h. Apart from feed rate, the influence of volume of concentrate and current on membrane performance was evaluated to optimize current utilization. An estimation of energy requirement of an integrated process constituting ED and evaporation for concentration of inorganics present in textile effluent from 4.35% to 24% was made and found to be approximately one eighth of the operating cost incurred by evaporation alone. Detailed design of a commercial ED system revealed that a membrane area of 13.1 m2 was required to treat a feed rate of 1500 L/h. The payback period to recover capital investment was found to be 110 days. 相似文献
57.
Ashok Kumar Singh N. Chaurasia Shahla Rahmani Jaya Srivastava Bharat Singh 《Catalysis Letters》2004,94(3-4):135-141
The NO/H2 reaction has been studied over a Ni loaded carbon film catalysts using in situ FTIR spectroscopy at the temperature range 25–350°C. On these catalysts, the differences in activity and selectivity were found depending on the nature of the surface functional groups. These differences were correlated with transient infrared spectral features which appeared during the reaction. It has been proved experimentally that the chemical character of the support is of vital importance during the process. The rise in NO conversion and N2 selectivity was observed when the surface of the catalysts was changed by the NH3 chemisorption. Amide and/or imide species formed due to the reduction of ammonium salts of carboxylic acids can play a significant role as active centers during the NO reduction. 相似文献
58.
首先提出一个广义电压崩溃指标(Generalized Voltage Collapse Index,缩写为GVCI),定义为含有大容抗的长距离辐射型输电系统(架空线或海底电缆)距离最大稳定极限负荷的当前负荷裕度.GVCI为瞬时值,可用于保护和控制装置的整定,通过相量测量单元(PMU)所提供的局部测量值实现控制和保护功能.用一个简单的两母线双回线系统对所提出的GVCI指标的有效性进行了测试,通过扩展GVCI,用解析方式分析有载调压变压器(OLTC)的运行对电压崩溃的影响;并将GVCI与分析电压崩溃时常用的L指标进行了比较,讨论GVCI在地理位置偏远的风力发电场的可能应用. 相似文献
59.
This paper discusses the effect of varying the shock pulse width on the shock response of small form factor hard disk drives. We develop a new shock simulator for hard disk drives which simulates the structural as well as the air bearing dynamics of the disk drive simultaneously. We observe that the response of the disk to the shock pulse is of critical importance and depends strongly on the pulse width of the shock pulse. We also find that if a suspension bending frequency is close to the first umbrella frequency of the disk, there can be failure of the head–disk interface due to resonance. 相似文献
60.
Neural Computing and Applications - We propose “Deep Autoencoders for Feature Learning in Recommender Systems,” a novel discriminative model based on the incorporation of features from... 相似文献