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1.
Wireless Networks - One of the biggest challenges of distributed software defined networks (SDNs) is to create load balancing on controllers to reduce response time. Although recent studies have... 相似文献
2.
A biochar from casein and its properties 总被引:2,自引:0,他引:2
A biochar was prepared by pyrolysis of casein. A helium and mercury porosimeter were used to measure the true and apparent densities of the chars respectively, elemental and IR analysis were used to characterize the chemical composition of char. A SEM was used to observe the char surfaces in order to verify the presence of porosity. The biochar has 9.02% of nitrogen, content of porosity is 20%. The experimental results show that it is possible to prepare chars with relatively high porosity from casein for the further preparation of activated carbon. 相似文献
3.
The results of a study of the chemical composition and technological properties of coals from the Khar Tarvagatai, Nuurst Khotgor, and Khushuut deposits are presented in this article. 相似文献
4.
Temperature dependence of propagation delay time and power-delay product in Si MOSFETs (fabricated using 1 μm X-ray lithography) has been measured using 19-stage ring oscillators. The delay time was found to decrease with lowering temperature. As a numerical example we found that a delay time of 30 ps at room temperature decreased to 22 and 18 ps at 77 and 4.2 K respectively, and increased to 38 at 400 K. The power showed a slight increase with decreasing temperature, while the power-delay product decreased. The decrease in the delay time has been explained in terms of increase in the electron drift velocity with decreasing temperature, as well as decrease in one component of the capacitive load, namely the source-drain junction capacitance, due to carrier freeze-out. 相似文献
5.
Vukusic J. Bryllert T. Arezoo Emadi T. Sadeghi M. Stake J. 《Electron Device Letters, IEEE》2007,28(5):340-342
We present a high-power InAlAs/InGaAs/InP heterostructure barrier varactor (HBV) frequency tripler. The HBV device topology was designed for efficient thermal dissipation and high efficiency. To verify simulations, the device was flip-chip soldered onto embedding microstrip circuitry on an aluminum nitride substrate. This hybrid circuit was then mounted in a waveguide block without any movable tuners. From the resulting RF measurements, the maximum output power was 195 mW at 113 GHz, with a conversion efficiency of 15%. The measured 3-dB bandwidth was 1.5% 相似文献
6.
Mehrorang Ghaedi Javad Tashkhourian Arezoo Amiri Pebdani Batol Sadeghian Fatemeh Nami Ana 《Korean Journal of Chemical Engineering》2011,28(12):2255-2261
The proposed research describes the synthesis and characterization of platinum nanoparticles loaded on activated carbon (Pt-NP-AC)
and its efficient application as novel adsorbent for efficient removal of reactive orange 12 (RO-12). The influences of effective
parameters following the optimization of variables on removal percentages, their value was set as 0.015 g Pt-NP-AC, pH 1,
contact time of 13 min. At optimum values of all variables at 25 and 50 mgL−1 of RO-12 enthalpy (ΔH0) and entropy (ΔS0) changes was found to be 59.89 and 225.076, respectively, which negative value of ΔG0 shows a spontaneous nature, and the positive values of ΔH0 and ΔS0 indicate the endothermic nature and adsorption organized of dye molecule on the adsorbent surface. Experimental data was
fitted to different kinetic models including first-order, pseudo-second-order, Elovich and intra-particle diffusion models,
and it was seen that the adsorption process follows pseudo-second-order model in consideration to intra-particle diffusion
mechanism. At optimum values of all variables, the adsorption process follows the second-order kinetic and Langmuir isotherm
model with adsorption capacity 285.143 mg g−1 at room temperature. 相似文献
7.
S. A. Semenova T. I. Gulyaeva V. A. Drozdov O. V. Protasova T. S. Manina N. I. Fedorova Z. R. Ismagilov B. Avid 《Solid Fuel Chemistry》2013,47(6):342-348
The results of a study of the physicochemical characteristics of porous carbon materials prepared based on low-metamorphosed black coal from the Khar Tarvagatai deposit in Mongolia are presented in this article. The carbon material synthesized with the use of an alkaline impregnation method corresponds to uniformly porous, predominantly, microporous (to 70% of micropores in terms of adsorption volume) sorbents with a specific surface area of ~1100 m2/g. The use of additional ozonolytic activation of the sorbent facilitated an insignificant decrease in its porosity with an increase in the number of oxygen groups on the sample surface by a factor of 2.5 in this case. 相似文献
8.
Arezoo Khosravi Hadi Baharifar Mohamad Hasan Darvishi Ali Akbar Karimi Zarchi 《IET nanobiotechnology / IET》2020,14(9):899
Tissue plasminogen activator (tPA) a thrombolytic agent is commonly used for digesting the blood clot. tPA half‐life is low (4–6 min) and its administration needs a prolonged continuous infusion. Improving tPA half‐life could reduce enzyme dosage and enhance patient compliance. Nano‐carries could be used as delivery systems for the protection of enzymes physically, enhancing half‐life and increasing the stability of them. In this study, chitosan (CS) and polyethylene glycol (PEG) were used for the preparation of CS‐g‐PEG/tPA nanoparticles (NPs) via the ion gelation method. Particles’ size and loading capacity were optimised by central composite design. Then, NPs cytotoxicity, release profile, enzyme activity and in vivo half‐life and coagulation time were investigated. The results showed that NPs does not have significant cytotoxicity. Release study revealed that a burst effect happened in the first 5 min and resulted in releasing 30% of tPA. Loading tPA in NPs could decrease 25% of its activity but the half‐life of it increases in comparison to free tPA in vivo. Also, blood coagulation time has significantly affected (p ‐value = 0.041) by encapsulated tPA in comparison to free tPA. So, CS‐g‐PEG/tPA could increase enzyme half‐life during the time and could be used as a non‐toxic candidate delivery system for tPA.Inspec keywords: drug delivery systems, nanofabrication, drugs, nanomedicine, coagulation, biomedical materials, cellular biophysics, enzymes, biochemistry, toxicology, molecular biophysics, biological tissues, blood, nanoparticles, polymersOther keywords: chitosan‐g‐PEG grafted nanoparticles, half‐life enhancer carrier, tissue plasminogen activator delivery, tPA half‐life, prolonged continuous infusion, enzyme dosage, polyethylene glycol, cytotoxicity, enzyme activity, encapsulated tPA, enzyme half‐life, blood coagulation, time 5.0 min 相似文献
9.
Seismic performance evaluation of steel moment resisting frames through incremental dynamic analysis 总被引:2,自引:0,他引:2
Earthquake hazards effect significant damage to structures and cause widespread failure throughout buildings. Moment resisting frames are widely used as lateral resisting systems when sufficient ductility is to be met. Generally three types of moment resisting frames are designed in practice namely Special, Intermediate and Ordinary Moment Frames, each of which has certain level of ductility. Comparative studies on the seismic performance of these three different types of structure are performed in this study. Analytical models of connections are employed including panel zone and beam to column joint model. Incremental dynamic analysis is then utilized to assess the structural dynamic behavior of the frames and to generate required data for performance based evaluations. Maximum annual probability of exceeding different limit states may reveal the superiority of a ductile structure in which a greater behavior factor is employed. Special moment resisting frames are expected to perform better once a certain level of ductility is to be met but the amount of superiority may be the subject of investigation especially from a performance based design standpoint. 相似文献
10.
Influence of two nano-size additives on electrical properties of suspension matrix of self-flowing low-cement high alumina refractory castable is investigated. For this purpose, castament FS 10 and FS 20 on the basis of polycarboxylate ether were considered. The self-flow value, workability and mechanical strength of the castable are evaluated and their relations with electrical conductivity are determined. Using these relations, the type and optimum amount of proper additive for these refractory castables are determined. It was shown that if the electrical conductivity of matrix suspension is less than 0.71 mS/cm, high alumina low-cement self-flowing refractory castable can be obtained. The best self-flow, sufficient working time and adequate mechanical strength in the castables are obtained with 0.08 wt.% FS 20. 相似文献