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91.
The high-energy current of runaway electrons during a major disruption in tokamak reactors can cause serious damage to the first wall of the reactors and reduce their life time. Therefore, finding a method to minimize runaway electron generation during a major disruption is much needed. Tokamak limiter biasing is one of the methods that can be used for controlling the radial electric field and can induce a transition to an improved confinement state. This paper attempts to examine the effect of limiter biasing on the generation of runaway electrons during a major disruption. To do so, a horizontal biased limiter placed on the tokamak was used. Main parameters such as plasma current, loop voltage, emitted hard X-ray intensity, magnetohydrodynamic (MHD) oscillation and Hα radiation and spectrum of hard X-rays, in the presence and absence of negative and positive limiter biasing, were measured. The results show that the application of limiter biasing during a major disruption can reduce runaway electron generation. 相似文献
92.
93.
Mina Neghabi Abbas Behjat Bi Bi Fatemeh Mirjalili Leila Zamani 《Current Applied Physics》2013,13(1):302-306
One of the porphyrin derivatives, meso-tetraphenylporphyrin (TPP), has been synthesized and examined as an emitter material (EM) for efficient fluorescent red organic light-emitting diodes (OLEDs). By inserting a tungsten oxide (WO3) layer into the interface of anode (ITO) and hole transport layer N,N′-Di-[(1-napthyl)-N,N′-diphenyl]-(1,1′-biphenyl)-4,4′-diamine (NPB) and by using fullerene (C60) in contact with a LiF/Al cathode, the performance of devices was markedly improved. The current density–voltage–luminance (J–V–L) characterizations of the samples show that red OLEDs with both WO3 and C60 as buffer layers have a lower driving voltage and higher luminance compared with the devices without buffer layers. The red OLED with the configuration ITO/WO3 (3 nm)/NPB (50 nm)/TPP (60 nm)/BPhen (30 nm)/C60 (5 nm)/LiF (0.8 nm)/Al (100 nm) achieved the high luminance of 6359 cd/m2 at the low driving voltage of 8 V. At a current density of 20 mA/cm2, a pure red emission with CIE coordinates of (0.65; 0.35) is observed for this device. Moreover, a power efficiency of 2.07 lm/W and a current efficiency of 5.17 cd/A at 20 mA/cm2 were obtained for the fabricated devices. The study of the energy level diagram of the devices revealed that the improvement in performance of the devices with buffer layers could be attributed to lowering of carrier-injecting barrier and more balanced charge injection and transport properties. 相似文献
94.
Ebrahim Kianmehr Narges Shamsaei Zafarghandi Mohammad Ghanbari 《Molecular diversity》2013,17(2):383-388
Novel $N$ -alkyl-2-(alkylthio)-1 $H$ -imidazole derivatives were synthesized in a single step by an efficient and simple method in high yields. Readily available starting materials, mild reaction conditions, operational simplicity and novelty are the key advantages of this method. Besides their novel structures, these compounds may have important biological activities and industrial applications. 相似文献
95.
Tsutomu Asano Takuro Furusho Mohammad Mahay Alam Yukihiro Tamba Chie Sawatari Md. Forhad Mina 《Journal of Macromolecular Science: Physics》2013,52(4):774-788
Isotactic polypropylene (iPP) film was melt-crystallized in a temperature gradient. The iPP film showed well oriented α- and β-crystalline textures along the gradient. The crystalline structure, phase transition boundary and lamellar twisting were examined by X-ray diffraction and laser light diffraction (LLD). On the α-β boundary, LLD shows a sharp streak perpendicular to the boundary, where the a-axis of the β-crystal is oriented perpendicular to the temperature gradient. Apart from the boundary, the a-axis of the β-crystal becomes parallel to the gradient. The β-crystal shows lamellar twisting with a pitch of 200 μm at room temperature. When heated the β-crystal, the lamellar distance of 295Å at room temperature decreases to 285Å at 80–100°C and then increases to more than 300Å above 120°C. During the heating, the value of the twist period increases from 200 to 210 μm at 90–100°C, and then to above 224 μm at 140°C. The increase of the twist period is related to the increasing crystalline thickness of the β-lamellae. 相似文献
96.
Structural Chemistry - Adsorption and reaction mechanisms for the noncovalent and covalent functionalization of SiO2 nanoparticle (SiNP) with gemcitabine (GEM) anticancer drug have been... 相似文献
97.
Koji Haruta Mina Ye Yu-ichiro Takemura Tomohiro Kobayashi Tatsuo Ishikawa Jhantu Kumar Saha Hajime Shirai 《Journal of Non》2008,354(19-25):2333-2336
The rapid crystallization of amorphous silicon utilizing the radio-frequency (rf) inductive coupling thermal plasma torch of argon is demonstrated. Highly-crystallized Si films were fabricated on thermally grown (th-)SiO2 and textured a-Si:H:B/SnO2/glass by adjusting a distance between the tip of the silica tube and the substrate stage and the translational velocity of the substrate stage. The crystallization was promoted efficiently from the bottom to front surface during the solidification and crystallization of liquid Si. 相似文献
98.
Molecular Diversity - In this research, QSAR modeling was carried out through SMILES of compounds and on the basis of the Monte Carlo method to predict the antioxidant activity of 79 derivatives of... 相似文献
99.
100.
Khadijeh Ghanbari Sepideh Bonyadi 《International Journal of Polymer Analysis and Characterization》2020,25(3):105-125
AbstractIn this study, the Pt nanoparticles/over-oxidized polypyrrole nanofiber/reduced graphene oxide (Pt NPs/OPPy/RGO) nanocomposite was electrochemically synthesized and used to modify a glassy carbon electrode. To confirm the Surface morphology and characterization of the nanocomposite, field emission scanning microscopy (FE-SEM), X-ray diffraction (XRD), Raman, FT-IR, and X-ray photoelectron spectroscopy (XPS) were used. Simultaneous determination of these species showed one linear response 0.1–250.0?μM and two linear responses 0.5–10.0?μM and 10.0–470.0?μM, with detection limits 42?nM and 106?nM (S/N?=?3) for DA and 5-HT, respectively. Finally, the analytical application of this modified electrode was investigated in the human blood plasma. 相似文献