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排序方式: 共有2259条查询结果,搜索用时 31 毫秒
91.
Hamid Reza Shokouhfar Hamed Jooypa Daryoosh Dideban 《Analog Integrated Circuits and Signal Processing》2018,95(2):295-306
In this paper, the context of modeling of the impact of mismatch and statistical variations on analogue circuit building blocks is emphasized. The aim is to develop a new algorithm which predicts the statistical behavior of important parameters of an amplifier including output resistance, voltage gain and trans-conductance. The relative error of standard deviation of statistical parameters will remain less than 5% compared with the most accurate Monte-Carlo (MC) simulations using atomistic library model-cards. In comparison with other models which are based on the normal distribution of parameters, the proposed model does not need this limiting presumption. On the other hand, the proposed algorithm is more efficient compared with time consuming MC atomistic simulations. 相似文献
92.
Hamed Aminzadeh 《Analog Integrated Circuits and Signal Processing》2018,95(2):271-282
Hybrid cascode feedforward compensation (HCFC) is an effective technique to stabilize nano-scale three-stage amplifiers driving ultra-large load capacitors. It divides the compensation capacitance and shares it between two high-speed local feedback loops embedded within the amplifier core. In this article, a systematic approach to analyze the transfer function and to evaluate the pole expressions of nano-scale HCFC amplifiers is presented. For the first time, the equivalent output impedance is successfully modeled to approximate the complicated transfer function of the HCFC amplifier without the need for lengthy pencil-and-paper calculations. An HCFC amplifier is designed and simulated in 90-nm CMOS technology, to verify the effectiveness of the new analytic approach. The simulated transfer function of the amplifier is almost identical to a calculated transfer function derived based on the new model. 相似文献
93.
Hosseini M. Mofidi M. R. Jamalpoor A. Safi Jahanshahi M. 《Microsystem Technologies》2018,24(5):2295-2316
Microsystem Technologies - In the current paper, the sensitivity performance of functionally graded magneto-electro-elastic (FG-MEE) nanoplate with attached nanoparticles as a nanosensor is... 相似文献
94.
Hamed Bazrafshan Razieh Shajareh Touba Zahra Alipour Tesieh Saeideh Dabirnia Bahram Nasernejad 《Chemical Engineering Communications》2017,204(10):1105-1112
In this study, Co3O4 nanosheets were synthesized through hydrothermal method using cobalt nitrate hexahydrate. X-ray diffraction, diffuse reflectance spectra, Fourier transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, and field emission scanning electron microscopy were applied to investigate the properties of as-synthesized samples. Ultimately, the electrochemical and photoelectrochemical properties were evaluated by Mott–Schottky analysis and measuring photoconversion efficiency of Co3O4 nanosheets. The results indicated that Co3O4 nanosheets exhibited a maximum efficiency of 0.92% for water electrolysis under simulated 1.5 global sunlight air mass, which further suggests the excellent potential of Co3O4 nanosheets for application in hydrogen generation through photocatalytic water splitting. 相似文献
95.
Morteza Hosseini 《Korean Journal of Chemical Engineering》2011,28(2):507-510
Solubility of carbon monoxide in water is very important for its biological oxidation or removal process of gaseous pollutants.
Present research shows the effect of pressure on solubility of carbon monoxide in liquid phase and its removal process by
a biofilter. The results are considered as laboratory research on carbon monoxide elimination. In this method a pressurized
trickle-bed biofilter was used to increase pressure in the reactor. The biofilter was filled with Leca-stones and inoculated
with microorganisms. When the system’s pressure is increased, the solubility of carbon monoxide will be increased, respectively,
and it causes a better reaction of the microorganisms for removing of gaseous pollutants. The efficiency was improved significantly
by increasing the pressure in the reactor. 相似文献
96.
The paper studied by Subbaraj et al. (2009) considers the feasibility of using self adaptive real-coded genetic algorithm for enhancement of combined heat and power economic dispatch. The paper includes some problems about the considered feasible operating region. In this discussion, the controversial point of the paper are given. 相似文献
97.
This paper investigated the uniaxial mechanical properties of a new type of hollow sphere structures. For this new type, the sphere shell was perforated by several holes in order to open the inner sphere volume and surface. The mechanical properties, i.e. elastic properties and initial yield stress of perforated hollow sphere structures (PHSS) in a primitive cubic arrangement were numerically evaluated for different hole diameters and different joining techniques of the hollow spheres. The results are compa... 相似文献
98.
Seyed Hamed Barghi Theodore T. TsotsisMuhammad Sahimi 《International Journal of Hydrogen Energy》2014
The question of chemisorption versus physisorption during hydrogen storage in carbon nanotubes (CNTs) is addressed experimentally. We utilize a powerful measurement technique based on a magnetic suspension balance coupled with a residual gas analyzer, and report new data for hydrogen sorption at pressures of up to 100 bar at 25 °C. The measured sorption capacity is less than 0.2 wt.%, and there is hysteresis in the sorption isotherms when multi-walled CNTs are exposed to hydrogen after pretreatment at elevated temperatures. The cause of the hysteresis is then studied, and is shown to be due to a combination of weak sorption – physisorption – and strong sorption – chemisorption – in the CNTs. Analysis of the experimental data enables us to calculate separately the individual hydrogen physisorption and chemisorption isotherms in CNTs that, to our knowledge, are reported for the first time here. The maximum measured hydrogen physisorption and chemisorption are 0.13 wt.% and 0.058 wt.%, respectively. 相似文献
99.
Mohammad Saeid Hosseini Ali Akbar Bazrafshan Ahmad Hosseini-Bandegharaei 《分离科学与技术》2016,51(8):1328-1335
A new solvent-impregnated resin (SIR) was constructed using Amberlite XAD-2 and 3-hydroxy-2-naphthoic acid (3H2NA). The SIR was applied for stepwise extraction of Th(IV) and U(VI) from the coexistence ions dissolved in aqueous media at pHs of 3.0 and 7.0, respectively. The U(VI) and Th(IV) ions adsorbed on the minicolumn were consecutively eluted with 0.5 M and 4 M HCl solutions. They were then measured by Arsenazo III at their maximum absorption wavelengths. The characteristic parameters for the successful separation of these ions from the aqueous media were investigated. The SIR showed excellent reproducibility during the 800 subsequent extraction cycles. 相似文献
100.
Ahmad Jonidi Jafari Babak Kakavandi Roshanak Rezaei Kalantary Hamed Gharibi Anvar Asadi Ali Azari Ali Akbar Babaei Afshin Takdastan 《Korean Journal of Chemical Engineering》2016,33(10):2878-2890
Discharging the effluents of textile wastewaters into potable water resources can endanger the ecosystem, due to their reactivity, toxicity, and chemical stability. In this research, the application of powder activated carbon modified with magnetite nanoparticles (PAC-MNPs) as an adsorbent for removal of reactive dyes (Reactive black 5 (RB5) and reactive red 120 (RR120)) was studied in a batch system. The adsorption performance was evaluated as a function of temperature, contact time and different adsorbent and adsorbate concentrations. The levels of factors were statistically optimized using Box-Behnken Design (BBD) from the response surface methodology (RSM) to maximize the efficiency of the system. The adsorption process of both dyes was fit with the pseudo-second order kinetic and Langmuir isotherm models. The identified optimum conditions of adsorption were 38.7 °C, 46.3 min, 0.8 g/L and 102 mg/L for temperature, contact time, adsorbent dose, and initial dyes concentration, respectively. According to the Langmuir isotherm, the maximum sorption capacities of 175.4 and 172.4 mg/g were obtained for RB5 and RR120, respectively. Thermodynamics studies indicated that the adsorption process of the reactive dyes was spontaneous, feasible, and endothermic. After five cycles, the adsorption efficiency was around 84 and 83% for RB5 and RR120, respectively. A high value of desorption was achieved, suggesting that the PAC-MNPs have a good potential in regeneration and reusability, and also can be effectively utilized in industrial applications. PAC-MNPs also show a good anti-interference potential for removal of reactive dyes in dye-industry wastewaters. 相似文献