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排序方式: 共有499条查询结果,搜索用时 15 毫秒
1.
Mamatov Islombek zelep Yasin Kaar Frat 《Analog Integrated Circuits and Signal Processing》2022,110(1):127-137
Analog Integrated Circuits and Signal Processing - This paper presents carbon nanotube field effect transistor (CNTFET) implementation of voltage differencing current conveyor (VDCC). We propose... 相似文献
2.
Journal of Low Temperature Physics - This study modeled and investigated the magnetocaloric effect in Ni2MnGa Heusler alloy characterized by its magnetic entropy change (ΔSm) and its... 相似文献
3.
4.
A protein which masks galactose receptor mediated phage susceptibility in Lactococcus lactis subsp. lactis MPL56 总被引:1,自引:0,他引:1
Yasin Tuncer & Mustafa Akçelik 《International Journal of Food Science & Technology》2002,37(2):139-144
A 28.5-kb plasmid, isolated from Lactococcus lactis subsp. lactis MPL56, causes complete inhibition of four lactococcal phages. Cell wall characteristics of wild-type strain MPL56 were compared with its 28.5 kb plasmid-cured, phage-sensitive derivative MPL56-22. After proteolytic enzyme treatments, adsorption of phages occurred at high levels, an example is 94.6–98.5% in MPL56 cells. Analysis of cell wall extracts of MPL56-22 by sodium dodecyl sulphate–polyacrylamide gel electrophoresis (SDS–PAGE) indicated that the only difference between strains was the 55.4 kDa band in protein patterns of MPL56. Adsorption of the four phages was completely inhibited when MPL56-22 cells were subjected to SDS, Triton-X-100, HCl and NaOH treatments. Lectins that were specific for glucose/mannose and N-acetylglucosamine did not prevent adsorption of phages in cell wall extracts of MPL 56-22. However a lectin specific for galactose (MCA; Momordica charantia ) completely inhibited adsorption of these phages in cell wall extracts of MPL56-22. HPLC patterns of cell wall carbohydrates of MPL56-22 and its HCl treated preparations showed that the most prevalent difference was the galactose on untreated MPL56-22 cell wall chromatograms. 相似文献
5.
The electrical properties of CdTe thin film have been studied and discussed, including, the conduction mechanism, and the effect of temperature and indium doping on the current passing through the CdTe film and hence on the film conductivity. It is observed that the CdTe film is of the modified Poole–Frenkel conduction mechanism and the resistivity of the film can be lowered by more than one order of magnitude due to indium doping. 相似文献
6.
2-Hydroxy-1,4-napthoquinone(lawsone) natural red-orange dye was extracted from fresh henna(Lawsonia inermis) leaves in an alkaline media.The lawsone-surfactant solubilization constants(K_(LS))were calculated for the first time by using cationic cetyltrimethylammonium bromide(CTAB) and anionic sodium dodecyl sulphate(SDS).The standard free energy,concentration of solubilized lawsone and number of lawsone molecules solubilized into micelles were calculated and discussed.Surface excess,minimum surface area per molecule,surface pressure,free energy(adsorption and aggregation) and equilibrium constants of different states were determined from tensiometry.Different metal ions(Ag~+,Co~(2+),Cu~(2+),Ni~(2+),Fe~(3+),Zn~(2+) and Al~(3+)) were used to determine the complex forming ability with lawsone.Out of these,Ag~+ ions have strong binding capacity with lawsone.The adsorption of lawsone on the surface of glass with silver ions in presence of CTAB was also observed at pH 9.0.The pseudo-first, secondorder kinetic equation,intraparticles diffusion and Elovich models were used to determine the kinetics of lawsone adsorption onto the surface of glass and a probable mechanism has been discussed.Lawsone adsorption followed second-order kinetic equation(k_2=0.019 g·mg~(-1)·min~(-1)). 相似文献
7.
Ugur Ozdemir Yucel Orkut Aktas Aslihan Vuruskan Yasin Dereli Ahmed Farabi Tarhan Karaca Demirbag Ahmet Erdem Ganime Duygu Kalaycioglu Ibrahim Ozkol Gokhan Inalhan 《Journal of Intelligent and Robotic Systems》2014,74(1-2):371-393
For the last four decades Unmanned Air Vehicles (UAVs) have been extensively used for military operations that include tracking, surveillance, active engagement with weapons and airborne data acquisition. UAVs are also in demand commercially due to their advantages in comparison to manned vehicles. These advantages include lower manufacturing and operating costs, flexibility in configuration depending on customer request and not risking the pilot on demanding missions. Even though civilian UAVs currently constitute 3 % of the UAV market, it is estimated that their numbers will reach up to 10 % of the UAV market within the next 5 years. Most of the civilian UAV applications require UAVs that are capable of doing a wide range of different and complementary operations within a composite mission. These operations include taking off and landing from limited runway space, while traversing the operation region in considerable cruise speed for mobile tracking applications. This is in addition to being able traverse in low cruise speeds or being able to hover for stationary measurement and tracking. All of these complementary and but different operational capabilities point to a hybrid unmanned vehicle concept, namely the Vertical Take-Off and Landing (VTOL) UAVs. In addition, the desired UAV system needs to be cost-efficient while providing easy payload conversion for different civilian applications. In this paper, we review the preliminary design process of such a capable civilian UAV system, namely the TURAC VTOL UAV. TURAC UAV is aimed to have both vertical take-off and landing and Conventional Take-off and Landing (CTOL) capability. TURAC interchangeable payload pod and detachable wing (with potential different size variants) provides capability to perform different mission types, including long endurance and high cruise speed operations. In addition, the TURAC concept is to have two different variants. The TURAC A variant is an eco-friendly and low-noise fully electrical platform which includes 2 tilt electric motors in the front, and a fixed electric motor and ducted fan in the rear, where as the TURAC B variant is envisioned to use high energy density fuel cells for extended hovering time. In this paper, we provide the TURAC UAV’s iterative design and trade-off studies which also include detailed aerodynamic and structural configuration analysis. For the aerodynamic analysis, an in-house software including graphical user interface has been developed to calculate the aerodynamic forces and moments by using the Vortex Lattice Method (VLM). Computational Fluid Dynamics (CFD) studies are performed to determine the aerodynamic effects for various configurations For structural analysis, a Finite Element Model (FEM) of the TURAC has been prepared and its modal analysis is carried out. Maximum displacements and maximal principal stresses are calculated and used for streamlining a weight efficient fuselage design. Prototypes have been built to show success of the design at both hover and forward flight regime. In this paper, we also provide the flight management and autopilot architecture of the TURAC. The testing of the controller performance has been initiated with the prototype of TURAC. Current work focuses on the building of the full fight test prototype of the TURAC UAV and aerodynamic modeling of the transition flight. 相似文献
8.
Yassine Slimani Sagar E. Shirsath Essia Hannachi Munirah A. Almessiere Moustafa M. Aouna Nouf E. Aldossary Ghulam Yasin Abdulhadi Baykal Bekir Ozçelik Ismail Ercan 《Journal of the American Ceramic Society》2021,104(11):5648-5658
Two phase-based nanocomposites consisting of dielectric barium titanate (BaTiO3 or BTO) and magnetic spinel ferrite Co0.5Ni0.5Nb0.06Fe1.94O4 (CNNFO) have been synthesized through solid state route. Series of (BaTiO3)1-x + (Co0.5Ni0.5Nb0.06Fe1.94O4)x nanocomposites with x content of 0.00, 0.25, 0.50, 0.75, and 1.00 were considered. The structure has been examined via X-rays diffraction (XRD) and indicated the occurrence of both perovskite BTO and spinel CNNFO phases in various nanocomposites. A phase transition from tetragonal BTO structure to cubic structure occurs with inclusion of CNNFO phase. The average crystallites size of BTO phase decreases, whereas that for the CNNFO phase increases with increasing x in various nanocomposites. The morphological observations revealed that the porosity is highly reduced, and the connectivity between grains is enhanced with increasing x content. The optical properties have been investigated by UV−vis diffuse reflectance spectroscopy. The deduced band gap energy (Eg) value is found to reduce with increasing the content of spinel ferrite phase. The magnetic as well as the dielectric properties were also investigated. The analysis showed that CNNFO ferrite phase greatly affects the magnetic properties and dielectric response of BTO material. The obtained findings can be useful to enhance the performances of magneto-dielectric composite-based systems. 相似文献
9.
Adel Al Rai Elena Stojanovska Yasin Akgul Mohammad Mansoob Khan Ali Kilic Safak Yilmaz 《应用聚合物科学杂志》2021,138(7):49835
Highly porous free-standing co-poly(vinylidene fluoride)/modacrylic/SiO2 nanofibrous membrane was developed using electrically-assisted solution blow spinning method. The performance and the potential of the membrane as a lithium-ion battery separator were investigated. The addition of modacrylic enhanced the solution spinnability that resulted in defect-free membranes. Moreover, the presence of modacrylic enhanced the dimensional and thermal stabilities, while the addition of hydrophilic SiO2 nanoparticle enhanced both mechanical property and ionic conductivity. Combustion test results illustrated that the presence of modacrylic provide flame retarding property over a set of different polymeric-based membranes. Electrochemical performance results showed that the developed membrane can increase the battery capacity compared with the commercial separator. 相似文献
10.
Opinion target extraction is one of the core tasks in sentiment analysis on text data. In recent years, dependency parser–based approaches have been commonly studied for opinion target extraction. However, dependency parsers are limited by language and grammatical constraints. Therefore, in this work, a sequential pattern-based rule mining model, which does not have such constraints, is proposed for cross-domain opinion target extraction from product reviews in unknown domains. Thus, knowing the domain of reviews while extracting opinion targets becomes no longer a requirement. The proposed model also reveals the difference between the concepts of opinion target and aspect, which are commonly confused in the literature. The model consists of two stages. In the first stage, the aspects of reviews are extracted from the target domain using the rules automatically generated from source domains. The aspects are also transferred from the source domains to a target domain. Moreover, aspect pruning is applied to further improve the performance of aspect extraction. In the second stage, the opinion target is extracted among the aspects extracted at the former stage using the rules automatically generated for opinion target extraction. The proposed model was evaluated on several benchmark datasets in different domains and compared against the literature. The experimental results revealed that the opinion targets of the reviews in unknown domains can be extracted with higher accuracy than those of the previous works. 相似文献