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131.
In this contribution, an attempt is made to investigate of evolution of some local and global plasma parameters in IR-T1 tokamak. For this purpose, four magnetic pickup coils were designed, constructed and installed on outer surface of the tokamak and then asymmetry factor is obtained from them. On the other hand, diamagnetic loop were designed and installed on IR-T1 and poloidal beta is determined from it. Therefore, the internal inductance and effective edge safety factor measured. Also, time evolution of the energy confinement time is measured using the diamagnetic loop. Experimental results show that maximum energy confinement time (which correspond to minimum collisions, minimum microinstabilities and minimum transport), relate to the low values of effective edge safety factor and also relate to the low values of internal inductance. 相似文献
132.
In this paper we presented poloidal flux loops technique for measurement of plasma horizontal displacement in the IR-T1 tokamak. In this technique, two poloidal flux loops were designed and installed on outer surface of the IR-T1 tokamak chamber, and then the plasma displacement was obtained from them. To compare the result obtained using this method, analytical solution is also experimented on the IR-T1. Results of the two methods are in good agreement with each other. 相似文献
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以丁二酸为交联剂,采用纳米TiO2和多壁碳管对棉织物进行改性。通过暴露于紫外和阳光照射,分析Direct Green6浓度的减少来评价改性织物的光催化自洁性能。探讨样品的紫外吸收、耐磨性与扩张强度。结果表明,在紫外和阳光照射下,经纳米TiO2和多壁碳管处理后的棉织物能有效提高Direct Green 6的光降解效率。改性织物的耐麿性和抗紫外性能提高,抗张强度略降低。Direct Green 6光降解效率的提高归因于电子空穴对重组的减少及由TiO2和多壁碳管产生协同作用而使吸收光的增加。 相似文献
136.
Mehdi Rashidi Aram Rezaei Salar Bijari Mehdi Jaymand Hadi Samadian Elham Arkan Saleh Salehi Zahabi Mehdi Hosseini 《应用聚合物科学杂志》2021,138(31):50755
The main focus of the current study was to fabricate fibrous nanocomposite based on polyacrylonitrile (PAN) fibers containing Bi2O3 NPs as the X-ray shielding material. Bi2O3 NPs were synthesized based on the solid dispersion evaporation method and dispersed into PAN polymer solution with different weight concentrations. The electrospinning technique was used to fabricate nanocomposite. The morphology, surface functional group, wettability, elemental analysis, and X-ray shielding efficacy of the fabricated nanocomposite were thoroughly evaluated. The dimeter of the fibrous nanocomposites containing 10, 20, and 30 wt% Bi2O3 NPs were 1.33 ± 0.08, 1.01 ± 0.11, and 1.69 ± 0.32 μm, respectively. EDX elemental analysis showed that NPs were uniformly distributed into/onto the fibers. The X-ray shielding studies showed that the prepared nanocomposites effectively attenuate the intensity of the X-ray. The entrance surface dose for the negative control was 24.10 ± 1.71 mSv and the application of the nanocomposites significantly reduced the entrance surface dose. The results showed NPs concentration-dependent CT number shift as the indication of X-ray protection and the highest value was obtained by 30 wt% NPs. The obtained results implied that the fabricated nanocomposites effectively attenuate the radiation and they could be applied as the X-ray shielding materials. 相似文献
137.
Porous glasses were prepared by partial sintering of waste glasses. Polyvinyl alcohol was added as a binder to the glass powder and the mixture was un-axially cold pressed under two different forces, followed by sintering at 700 °C. The effects of thermal history, particle size of glass powder, binder content and applied pressing forces on pore size and total porosity of fabricated porous glasses were investigated and final products with the porosity of 15–32 % were prepared. The average pore size of the specimens was determined using mercury porosimetry. The morphology of the porous glasses was observed by scanning electron microscopy. These produced porous glasses can be used for selective and accurate filtration. 相似文献
138.
Demonstration of functioning heterotopic gastric mucosa with 99mTc-pertechnetate SPECT is reported. Abnormal tracer uptake was shown conclusively with SPECT but not with planar imaging. When a Meckel's diverticulum is suspected, we suggest SPECT be performed if the results of planar scintigraphy are equivocal and that it be considered if there is a high clinical suspicion and planar imaging is normal. 相似文献
139.
Ionic liquids in supercritical methanol greatly enhance transesterification reaction for high‐yield biodiesel production 下载免费PDF全文
V. M. Ortiz‐Martínez M. J. Salar‐García F. J. Hernández‐Fernández P. Olivares‐Carrillo A. P. de los Ríos J. Quesada‐Medina 《American Institute of Chemical Engineers》2016,62(11):3842-3846
Biodiesel production is one of the most promising future alternatives to replacing fossil fuels. This work studies the use of ionic liquids (ILs) as potential catalysts in supercritical methanol for biodiesel production from non‐edible oil. The transesterification reaction of karanja oil was investigated in supercritical methanol in the presence of two respective ILs, [BMIM+][ ] and [Chol+][H2 ]. The reaction was performed in a one‐step batch process at several temperatures and percentages by weight of catalyst (w/woil). The results obtained show that the IL [Chol+][H2 ] allows a high yield of fatty acid methyl esters to be achieved in a short reaction time (above 95% in 45 min). A catalytic mechanism is also proposed for the IL that offered significant catalytic activity. This work investigates the effects of the use of ionic liquids as potential catalysts in supercritical methanol for the transesterification reaction of non‐edible oil. The reported reaction times to obtain biodiesel yields above 90% through the transesterification reaction of karanja oil range between 90 min and 8 h. ILs as catalysts in supercritical methanol drastically reduce reaction time (45 min) to obtain high fatty acid methyl ester yield (95.6%). © 2016 American Institute of Chemical Engineers AIChE J, 62: 3842–3846, 2016 相似文献
140.
Yaghoub Mansoori Salar Hemmati Parvin Eghbali Mohammad Reza Zamanloo Golamhassan Imanzadeh 《Polymer International》2013,62(2):280-288
This paper reports experiments on grafting of a new polymerizable monomer onto organophilic montmorillonite. The monomer, 5‐methacryloyloxy‐1,4:36‐D ‐anhydrosorbitol (MAS), was synthesized by reacting methacryloyl chloride and isosorbide in the presence of Et3N as base. Then, Cloisite 20A was reacted with vinyltrichlorosilane to replace the edge hydroxyl groups of the clay with a vinyl moiety. Because the reaction liberates HCl, it was performed in the presence of sodium hydrogen carbonate to prevent the exchange of quaternary alkylammonium cations with H+ ions. Only the silanol groups on the edge of the clay react with vinyltrichlorosilane. After the reaction, the product maintained the same basal spacing as the precursor. The radical polymerization of the product with MAS as a vinyl monomer led to chemical grafting of the polymer onto the montmorillonite surface. The homopolymer formed during polymerization was separated from the grafted organoclay by Soxhlet extraction. Chemical grafting of the polymer onto Cloisite 20A was confirmed using infrared spectroscopy. The prepared nanocomposite materials and the grafted nanoparticles were studied using X‐ray diffraction and scanning and transmission electron microscopy. Exfoliated nanocomposite was obtained for 1 wt% clay loadings. The nanocomposites were studied using thermogravimetric and dynamic mechanical analyses. Improved thermal properties were observed for nanocomposites with 1–5 wt% clay content. © 2012 Society of Chemical Industry 相似文献