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1.
Yixuan ZHOU Huajie WANG Yi YU Yihang CHEN Rui KE Min XU Chijie XIAO Zhanhui WANG Jiquan LI Xuru DUAN Minyou YE 《等离子体科学和技术》2021,23(7):75105-52
In this article, we present the optical design of a novel diagnostic on the HL-2 A tokamak, i.e. the20-channel edge Lyman-alpha beam emission spectroscopy, which is a promising solution for edge density turbulence research on tokamaks, as it offers the possibility of density fluctuation measurement with a 3.3 mm spatial resolution while maintains a high temporal resolution of1 μs. The optical path, including the reflective collection optics, the high-dispersion spectrometer, and the linear detector array, is carefully optimized to obtain a good image quality and a high throughput. The maximum root mean square radius of the collection optics is 64 μm.The detected photon flux is estimated to be about 10~(11) photons/s/channel. 相似文献
2.
Zhong-Zheng Jin Min Zha Hai-Long Jia Pin-Kui Ma Si-Qing Wang Jia-Wei Liang Hui-Yuan Wang 《材料科学技术学报》2021,81(22):219-228
In this study,we successfully prepared a Mg-6Zn-0.2Ca alloy by utilizing sub-rapid solidification (SRS)combined with hard-plate rolling (HPR),whose elongation-to-failure increases from ~17 % to ~23 %without sacrificing tensile strength (~290 MPa) compared with its counterpart processed via conven-tional solidification (CS) followed by HPR.Notably,both samples feature a similar refined grain structure with an average grain size of ~2.1 and ~2.5 μm,respectively.However,the high cooling rate of ~ 150 K/s introduced by SRS modified both the size and morphology of Ca2Mg6Zn3 eutectic phase in comparison to those coarse ones under CS condition.By subsequent HPR,the Ca2Mg6Zn3 phase was further refined and dispersed uniformly by severe fragmentation.Specially,the achieved supersaturation containing exces-sive Ca solute atoms due to high cooling rate was maintained in the SRS-HPR condition.The mechanisms that govern the high ductility of the SRS-HPR sample could be ascribed to following reasons.First,refined Ca2Mg6Zn3 eutectic phase could effectively alleviate or avoid the crack initiation.Furthermore,excessive Ca solute atoms in α-Mg matrix result in the yield point phenomenon and enhanced strain-hardening ability during tension.The findings proposed a short-processed strategy towards superior performance of Mg-6Zn-0.2Ca alloy for industrial applications. 相似文献
3.
A series of Au/[Ni Co/Bi]x/Au(x = 2, 3) films were fabricated by pulsed laser deposition method. In order to induce the in-plane uniaxial magnetic anisotropy(IPUMA) of the multifilms, multiple layers and different oblique angles ranging from 0° to 30° for the substrate are applied during the deposition. The microstructures of the nanofilms were investigated by using X-ray diffraction(XRD) and transmission electronic microscope(TEM).And their magnetic properties were measured by an alternating gradient magnetometer. For the multicycle systems,using the method that with more periodic structures of Ni Co/Bi film is easier for inducing IPUMA than the less or the samples located with various angles. 相似文献
4.
Feng Wang Min Yao Haoyong Kan Jianping Kuang Ping Li Jiashuo Zhang Yixin Zhang 《中国化学工程学报》2021,28(12):3110-3116
Coal ash melting characteristics has a direct impact on the smooth operation of entrained gasifier. Mineral conversion of coal ash is very significant to be investigated, because the mineral can affect the melting temperature and viscosity under high temperature conditions. In this paper, the effects of different Al2O3/CaO on the mineral conversion, melting temperature and viscosity of Ningdong coal ash are studied by the combination of experiment and simulation. The trend of melting temperature decreases firstly and rises with increasing Al2O3/CaO. The ash melting point reached to the lowest when the ratio is 1.23. XRD and Factsage software are used to analyze crystallization behavior of samples. The results show that the content of anorthite, albite and corundum increases and subsequently decreases, while the content of mullite decreases firstly and then rises with increasing Al2O3/CaO. High content with CaO can contribute to form albite and anorthite of low-melting. Besides, high content with Al2O3 can tend to produce mullite of high-melting. The results of experimental and simulation are basically the same, which lays a foundation for the melting characteristics of Ningdong coal ash and can provide technical support for the smooth operation of the entrained-gasifier. 相似文献
5.
Single-atom catalysis recently attracts great attentions,however,whether single atom or their nanoparticle(NP)has the advantage in its intrinsic activity remains under heated debate.Ag/Al2O3 is a widely used catalyst for many catalytic reactions,while the effect of Ag particle size on the actity is seldom investigated due to the great difficulty in synthesizing single atom Ag and Ag clusters/particles with different sizes.Herein,we firstly prepared an atomically dispersed Ag/Al2O3 catalyst using a nano-sized y-Al2O3 as the support,subsequently obtained a series of Ag/Al2O3 catalysts with different Ag particle sizes by H2 reducing single-atom Ag/Al2O3 catalyst at various temperatures.The Ag/Al2O3 treated at 600℃demonstrated superior CO oxidation performance over single-atom Ag/Al2O3 and the Ag/Al2O3 treated at 400 and 800℃.Based on experimental data and dpnsity functional theory(DFT)calculation results,we reveal that the larger Ag°particle is beneficial to oxygen activation and improves the valence stability during oxidation reaction,while the aggregation of Ag°particle also accordingly decreases the concentration of surface active sites,hence,there is an optimum Ag0 particle size.Our findings clearly confirm that Ag0nanoparticle has the advantage over single-atom Ag species in its intrinsic activity for CO oxidation. 相似文献
6.
Xuan-Tao Ji Si-Yuan Luo Yu-He Huang Kun Zhu Jin Zhu Xiao-Yu Peng Min Xiao Xiao-Dong Wang 《核技术(英文版)》2022,33(1):13-23
The muon radiography imaging technique for high-atomic-number objects(Z) and large-volume objects via muon transmission imaging and muon multiple scattering imaging remains a popular topic in the field of radiation detection imaging. However, few imaging studies have been reported on low and medium Z objects at the centimeter scale. This paper presents an imaging system that consists of three layers of a position-sensitive detector and four plastic scintillation detectors. It acquires data by co... 相似文献
7.
Chenyu WANG Lin NIE Guixin TANG Min XU Rui KE Yihang CHEN Huajie WANG Zhanhui WANG Shilin HU Ting WU Ting LONG Yuxuan ZHU Hao LIU Shaobo GONG Jinbang YUAN Longwen YAN 《等离子体科学和技术》2021,23(5):55103-48
Several results based on the Langmuir probes' data on the HL-2A tokamak are presented. The blob structures' radial and poloidal drift velocities, estimated by the gradient of floating potential and by time delay evaluation, are compared in different line-averaged density and electron cyclotron resonance heating conditions. A positive correlation is observed in the comparison between blobs' radial velocity estimated by the two methods mentioned above, regardless of the situation differences mentioned above. Correlation is also observed in the comparison between the blobs' poloidal velocity estimated by the two methods in different situations, while a shift due to the different line-averaged density is observed. These results imply that the radial gradient of floating potential may have some value as a reference during data analysis in low-parameter discharge. 相似文献
8.
将废轮胎切碎后与乙烯-乙酸乙烯酯共聚物(EVA)及沸石按一定比例混合制成一种辅助媒介,并添加至A2/O工艺的好氧段,考察了对脱氮效果的影响.试验结果表明,投加该媒介后可在好氧段内产生大量的微缺氧区,当维持污泥浓度为3~4 g/L、DO为1.6~2.4 mg/L以及进水C/N值为9~11、pH值为7.7~8.1的条件下,取得了较好的同步硝化反硝化效果,使脱氮能力提高了约13%. 相似文献
9.
10.
为了有效解决授权频段在恶劣环境下利用率低的问题,根据一种新信任度系数提取用可靠性较好的采样值参与本地单门限能量检测,并通过新信任度系数分簇获取可靠性较好的本地感知节点本地判决结果进行量化分类,簇头将本地认知节点量化结果、簇内平均权重系数及个数传至融合中心参与协作判决给出一种新的感知算法最后,实验仿真表明,该算法可以有效消除低可靠性认知节点参与协同判决,有效的缩减感知过程数据传输开销,提高系统感知性能。 相似文献