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91.
《Fusion Engineering and Design》2014,89(1):6-10
A high power (20 MW) and CW millimeter wave (mm-wave) injection is planned for Electron Cyclotron Heating and Current Drive (EC H&CD) in ITER. An optimization of the mm-wave system for the ITER EC H&CD Equatorial Launcher (EL) is performed. The optimization of the system is aimed to obtain the maximum transmission efficiency on the condition that 1.8 MW injection per waveguide, ∼20 cm in beam radius at the resonance layer and narrow opening of the Blanket Shielding Module (BSM). The transmission efficiency of 99.1% from the end of the waveguide inside the launcher to the output of the BSM is achieved.The mm-wave propagation with high order modes is also calculated by using an experimentally obtained high power mm-wave beam pattern that includes 95%HE11, 0.6%LP11, 0.2%LP02 and 4.2% other higher order modes. The analysis predicts the 1–2% additional loss will be induced by the high order modes. 相似文献
92.
CD317 (Tetherin,BST-2或HM1.24)于1994年被发现并命名,是终末分化B细胞的特异性表面标志.2008年首次被鉴定为干扰素诱导型宿主抗病毒因子,此后越来越多的科学家加入到该领域的探索中.经过近十年的研究,目前已经阐述了CD317结构、抗病毒及免疫特性等问题,也陆续发现了一些诸如参与肿瘤进展、束缚外泌体释放等新功能,研究热度不减当年.因此,文章对近几年CD317功能的研究进展进行一个系统的总结,以期为病毒感染、肿瘤发病以及治疗等方面的理论进步和技术发展提供新的思路. 相似文献
93.
《Planning》2016,(35):51-55
目的:探讨干燥综合征患者唇腺组织分泌功能损伤与TLR4、CD14的关系。方法:通过对干燥综合征患者唇腺组织进行免疫组化和逆转录聚合酶链式反应,来检测其中TLR4、CD14蛋白和mRNA的表达。结果:(1)TLR4和CD14在干燥综合征组唇腺组织中表达明显增高,对照组唇腺组织中未见TLR4、CD14表达;(2)按照病理分级,TLR4、CD14表达的阳性率分别为0~1级62.5%,2级70.0%,3级75.0%,4级58.3%,各组间TLR4、CD14表达阳性率差异均有统计学意义(P<0.05);(3)约64.4%PSS唇腺组织导管上皮细胞有TLR4、CD14的表达,在淋巴细胞灶中67.8%的淋巴细胞表达TLR4、CD14,但差异无统计学意义(P>0.05);(4)TLR4、CD14 mRNA在干燥综合征组唇腺组织中的表达明显高于对照组(P<0.05)。结论:TLR4、CD14在干燥综合征唇腺组织中高表达,干燥综合征唇腺组织分泌功能的损伤,可能与外源性感染启动TLR4、CD14信号传导通路有关;在干燥综合征发病机制中,导管上皮细胞主动参与了免疫损伤过程。 相似文献
94.
《Planning》2013,(3):18-19
以红继木、红苋和七彩扶桑的叶片为材料,采用丙酮-乙醇法提取,利用紫外-可见分光光度计对三种植物叶片中胡萝卜素、叶黄素和总类胡萝卜素的含量进行了测定。结果表明,胡萝卜素含量:红苋>红继木>七彩扶桑;叶黄素含量:七彩扶桑>红苋>红继木;总类胡萝卜素含量:红苋>红继木>七彩扶桑。 相似文献
95.
C.A. González-Rugerio R. Fuhrmeister D. Sudhoff J. Pilarczyk A. Górak 《Chemical Engineering Research and Design》2014
The design of catalytic distillation (CD) columns is a challenging task because of the superposition of chemical reaction and distillation in one apparatus. In this work, a method to design a cost-optimal CD column for chemical systems with large number of components and chemical reactions is presented. The method is based on the following steps: (1) estimation of the number of theoretical stages and catalyst volume by the decomposition of the CD column into a sequence of chemical reactors and non-reactive distillation columns, (2) estimation of the column diameter and operating conditions using an equilibrium stage model, and (3) design of the column applying an optimisation algorithm and using a rigorous non-equilibrium stage model to represent the CD process. The method is applied to determine the optimal column configuration and operating conditions for the synthesis of tert-amyl ethyl ether from ethanol and isoamylenes. Eight components and four chemical reactions were selected to represent the chemical system in the simulations. 相似文献
96.
《Journal of Industrial and Engineering Chemistry》2014,20(5):2830-2839
β-Cyclodextrin (CD) was grafted onto montmorillonite/iron oxides to prepare a novel magnetic CD/MMT/iron oxide composite by low-temperature plasma technology, and applied to remove U(VI) from aqueous solutions. The sorption irreversibility was attributed to inner-sphere binding of U(VI) on CD/MMT/iron oxide surface sites. The thermodynamic parameters indicated that the sorption of U(VI) on CD/MMT/iron oxide was an endothermic and spontaneous process. The maximum sorption capacity of U(VI) on CD/MMT/iron oxide was considerably higher than that of U(VI) on other reported materials. The CD/MMT/iron oxide can be potentially used as a cost-effective material for the purification of actual U(VI)-bearing effluents. 相似文献
97.
Martina Decker 《Architectural Design》2016,86(1):82-87
At best, the ageing of materials is regarded as lending a patina to historic buildings. In reality, however, materials often age disgracefully and unevenly, requiring a high level of maintenance and refurbishment. What if materials could be engineered and integrated into buildings not only to enhance but to heal? Martina Decker , Assistant Professor in the College of Architecture and Design at the New Jersey Institute of Technology (NJIT), looks at pioneering research that is being undertaken into performative, time-dependent materials. 相似文献
98.
研究了Si元素对Al-40Zn-xSi 钎料的钎焊性能,显微组织的影响以及不同Al-40Zn-xSi钎料对铝合金钎焊接头的显微组织和力学性能的影响。结果表明:当Al-40Zn-xSi中Si元素含量为4%时,钎料具有最好的润湿性能。显微组织分析表明:当Si元素含量超过4%后,钎料中开始出现块状初生硅;铝合金钎焊接头水冷后,Al-Si共晶组织和Zn-Al共析组织共存于焊缝中α-Al 的枝晶间区域。当钎料中Si元素的含量为4%时,焊后水冷的铝合金钎焊接头的抗剪强度达到最大值142.28 MPa。但是,当钎料中Si元素含量为5%以上时,焊缝中会形成较多的脆性共晶组织和初生硅颗粒,影响接头力学性能。 相似文献
99.
采用780℃亚温淬火和不同温度回火,探究回火温度对40CrMoVNbTi钢组织和力学性能的影响。对淬火不同温度回火40CrMoVNbTi钢的力学性能变化及显微组织和冲击断口断貌进行观察和分析。结果表明,780℃亚温淬火,随回火温度的提高,40CrMoVNbTi钢的强度下降,塑性呈上升趋势,300℃回火冲击吸收能量值最低,出现回火脆性。200℃回火组织为回火马氏体和残留奥氏体,其抗拉强度为2150 MPa,KV2为23.8 J;550~600℃回火组织为回火索氏体,韧性较好,其抗拉强度为1190~1070 MPa,KV2为94~123 J,满足AISI 4140钢的力学性能要求,具有较高的冲击性能。 相似文献
100.
《Carbon》2014
The objective of this study was to analyze the influence of the presence of activated carbon on the degradation of the triiodinated contrast medium diatrizoate (DTZ) by the simultaneous use of gamma radiation and activated carbon. Four commercial activated carbons (Ceca, Witco, Sorbo, and Merck) with different textural and chemical characteristics were used for this purpose. The percentage DTZ removal obtained was considerably higher with the gamma radiation/activated carbon (GM/AC) system than with radiolysis in the absence of activated carbon, and it depended on the specific activated carbon employed. First, we optimized the amount of activated carbon required to maximize the amount of DTZ removed by the GM/AC system (0.06 g). The degradation constants were higher with the GM/AC system than with radiolysis alone, evidencing a synergic effect that favors pollutant removal. This synergic effect is independent of the textural but not the chemical characteristics of the activated carbon, observing a higher synergic activity for carbons with a higher surface content of oxygen, specifically quinone groups. We also highlight that the synergic effect of the activated carbon requires adsorbent–adsorbate electrostatic interaction and is absent when this interaction is hindered. 相似文献