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排序方式: 共有252条查询结果,搜索用时 15 毫秒
61.
基于国际热核聚变实验反应堆磁约束聚变-裂变混合能源系统次临界包层的物理-热工设计结果,提出了聚变-裂变混合堆次临界包层燃料区结构设计方案,包括纵骨支撑结构、燃料区结构和锆包壳结构。运用Pro/e建模软件建立了次临界包层燃料区结构模型,并利用ANSYS-workbench mechanical有限元分析软件对纵骨式支撑结构开展了初步力学分析,得到了燃料部件和纵骨式多层支撑结构的最大Tresca应力值、应力分布云图和总变形量,其中最大应力为87.04 MPa,最大变形量为0.17mm。按照第3强度理论校核,计算结果表明纵骨式次临界包层结构各部件能够满足强度要求。 相似文献
62.
We report the gravity effects on the shape and focal length changes of liquid droplets. As the droplet size decreases, the gravity effect is gradually weakened. Moreover, if the outside space of the droplet is filled with another immiscible liquid rather than air, the filled liquid helps to offset the gravity effect even though their densities do not match well. Good agreement between experiment and simulation is obtained. The negligible gravity effect enables us to improve the optical performances of the liquid lens by choosing suitable liquids without worrying their density mismatch. 相似文献
63.
In this paper, hierarchically porous Fe2O3/CuO composite monoliths were first successfully synthesized by a mild method using silica monoliths as templates. The structure of composite monoliths was characterized by X-ray diffraction, scanning electron microscopy, nitrogen adsorption-desorption. The results indicated that the molar ratio of Fe to Cu had a great influence on the crystal phase of Fe2O3, pore size and the structure of the macroporous wall. The Fe2O3/CuO composite monoliths consist of hierarchically macroporous and mesoporous structure, while the sample with the Fe/Cu molar ratio of 2 : 1 possesses tighter wall structure than other samples. It is expected that as-prepared Fe2O3/CuO composite monoliths have potential applications in several fields as catalysts, catalyst supports, chemical sensors and high-performance liquid chromatography (HPLC). 相似文献
64.
Hongbing Wei Hongwen Sun Sumei Wang Guangzhi Chen Yingtao Hou Hongwen Guo Xiaodong Ma 《天然气化学杂志》2010,19(4):393-396
Nanostructured tin dioxide (SnO2) powders were prepared by a sol-gel dialytic process and and the doping of CuO on it was completed by a deposition-precipitation method. The thick film sensors were fabricated from the CuO/SnO2 polycrystalline powders. Sensing behavior of the sensor was investigated with various gases including CO, H2, NH3, hexane, acetone, ethanol, methanol and H2S in air. The as-synthesized gas sensor had much better response to H2S than to other gases. At the same time, the CuO/SnO2 sensor had enough sensitivity, together with fast response and recovery, to distinguish H2S from those gases at 160 and 210 ℃. Therefore, it might have promising applications in the future. 相似文献
65.
TiO2@Ni(OH)2 core-shell microspheres were synthesized by a facile strategy to obtain a perfect 3D flower-like nanostructure with well-arranged Ni(OH)2 nanoflakes on the surfaces of TiO2 microspheres; this arrangement led to a six-fold enhancement in photocatalytic hydrogen evolution. The unique p-n type heterostructure not only promotes the separation and transfer of photogenerated charge carriers significantly, but also offers more active sites for photocatalytic hydrogen production. A photocatalytic mechanism is proposed based on the results of electrochemical measurements and X-ray photoelectron spectroscopy. 相似文献
66.
β修正光度法测定土壤和岩石中铝 总被引:1,自引:0,他引:1
β修正光度法测定土壤和岩石中铝郜洪文,章鹏飞(安徽省淮北市环境监测站235000)(淮北煤炭师范学院化学系235000)关键词β修正吸光度,铝,土壤和岩石,甲基百里酚蓝β修正光度法是建立在显色剂和络合产物两种吸收光谱上新的微量分析法,它的原理不同于其... 相似文献
67.
研究了7种取代查耳酮肟的电化学行为。用氢氧化钠底液热解石墨工作电极,取代查耳酮肟的电极过程为1e氧化不可逆吸附电极过程。它们的氧化电位随取代基吸电子能力的增强而增高,并与它们相应的Hammett常数呈线性关系。取代查耳酮肟的电化学氧化机理为先失去一个电子生成iminoxy自由基,然后由基对分子内烯键进行环化加成,脱氢后形成3,5-二聚代异恶唑。用控电位电解和紫外吸收光谱检测了部份电化学氧化产物,证 相似文献
68.
69.
用两类结构不同的Schiff碱型、仲胺型双-(苯并-18-冠-6)在氯仿-水体系中对碱金属苦味酸盐进行萃取,测量了配合物组成比和萃取平衡常数。 相似文献
70.
前报曾报导了Mn(Ⅱ)的加速效应。此后又肯定了这一效应的普遍性及应用于流洗色谱的可能性。本文发现了4NHCl中的CuCl xx-2-是一种有效的加速离子,可以改善U(Ⅵ)的色谱床效,以此实现了U(Ⅵ)、Ti(Ⅳ)和Fe(Ⅲ)的色谱分离。 相似文献