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71.
曲轴作为发动机的核心部件,其破坏形式主要是轴颈圆角部位的疲劳失效。采用有限元法计算曲轴圆角处的应力集中系数,然后计算曲轴合格系数。与传统经验公式计算得到的合格系数进行对比分析可知:在进行曲轴设计时有限元法和经验公式法两种方法计算的合格系数均需满足要求,才能保证曲轴设计的安全裕度。 相似文献
72.
通过水平振荡毒性浸出试验,研究了硫化砷渣在不同的pH值和n(Ca)/n(As)下As的浸出。结果表明:浸出液pH值和n(Ca)/n(As)的不同,会对As的浸出质量浓度产生较大影响,pH在1.0113.12范围内时,随着pH值的增大,浸出液As的质量浓度先减小后增加,在pH=11.91时,达到最小值4.27 g/L;而随着n(Ca)/n(As)的增加,As的浸出质量浓度先增大后减小,在n(Ca)/n(As)=1.405时出现最大值,As浸出质量浓度为31.674 g/L。但总体来说n(Ca)/n(As)在(0.18713.12范围内时,随着pH值的增大,浸出液As的质量浓度先减小后增加,在pH=11.91时,达到最小值4.27 g/L;而随着n(Ca)/n(As)的增加,As的浸出质量浓度先增大后减小,在n(Ca)/n(As)=1.405时出现最大值,As浸出质量浓度为31.674 g/L。但总体来说n(Ca)/n(As)在(0.1875.619)范围内,加入Ca O宏观表现为促进硫化砷渣中As的溶出。 相似文献
73.
Yimei Chen Zhiping Deng Yongxiang Sun Yue Li Hao Zhang Ge Li Hongbo Zeng Xiaolei Wang 《纳微快报(英文)》2024,(5):291-305
The practical application of aqueous zinc-ion batteries for large-grid scale systems is still hindered by uncontrolled zinc dendrite and side reactions. Regulating the electrical double layer via the electrode/electrolyte interface layer is an effective strategy to improve the stability of Zn anodes. Herein, we report an ultrathin zincophilic ZnS layer as a model regulator. At a given cycling current, the cell with Zn@ZnS electrode displays a lower potential drop over the Helmholtz layer(stern l... 相似文献
74.
专用载波通道的纵联保护在系统中仍占有很大比例,但其运行情况并不很好,收发信机、通道衰耗异常变化等问题还比较突出,所以重点介绍了从配置、调试、维护、检验等各方面解决此问题的措施。 相似文献
75.
Lili Hao Wangyu Hu Chuan Wang Guangzong Wang Yue Sun Jun Chen Xueping Pan 《全球能源互联网(英文)》2023,(2):205-227
In an integrated energy system(IES) composed of multiple subsystems, energy coupling causes an energy supply blockage or shutdown in one subsystem, thereby affecting the energy flow distribution optimization of other subsystems.The energy supply should be globally optimized during the IES energy supply restoration process to produce the highest restoration net income. Mobile emergency sources can be quickly and flexibly connected to supply energy after an energy outage to ensure a reliable suppl... 相似文献
76.
Yue Zong Yuanlin Luo Yuechao Wu Jiande Huang Bowen Yang Xiaoyu Kang Shumei Liu Yao Yu 《中国通信》2023,(4):368-381
With the continuous integration of new energy into the power grid, various new attacks continue to emerge and the feature distributions are constantly changing during the deployment of intelligent pumped storage power stations. The intrusion detection model trained on the old data is hard to effectively identify new attacks, and it is difficult to update the intrusion detection model in time when lacking data. To solve this issue, by using model-based transfer learning methods, in this paper we ... 相似文献
77.
Yan-Yan Ding Yang-Bo Nie Yue Zhang Zhi-Jie Hu Qi Zhao Huan-Yu Zhang Kuo-Zhi Xu Shi-Yu Zhang Xin-Yi Pan Chang-Lin Lan Jie Ren Xi-Chao Ruan 《核技术(英文版)》2024,(2):123-137
A benchmark experiment on 238U slab samples was conducted using a deuterium–tritium neutron source at the China Institute of Atomic Energy. The leakage neutron spectra within energy levels of 0.8–16 MeV at 60° and 120° were measured using the time-of-flight method. The samples were prepared as rectangular slabs with a 30 cm square base and thicknesses of 3,6, and 9 cm. The leakage neutron spectra were also calculated using the MCNP-4C program based on the latest evaluated files of 相似文献
78.
Verification of Authentication Protocols for Epistemic Goals via SAT Compilation 总被引:1,自引:0,他引:1 下载免费PDF全文
Kai-Le Su Qing-Liang Chen Abdul Sattar Wei-Ya Yue Guan-Feng Lv and Xi-Zhong Zheng 《计算机科学技术学报》2006,21(6):932-943
This paper introduces a new methodology for epistemic logic, to analyze communication protocols that uses knowledge structures, a specific form of Kripke semantics over hostile networks. The paper particularly focuses on automatic verification of authentication protocols. Our approach is based on the actual definitions of a protocol, not on some difficultto-establish justifications. The proposed methodology is different from many previous approaches to automatic verification of security protocols in that it is justification-oriented instead of falsification-oriented, i.e., finding bugs in a protocol. The main idea is based on observations: separating a principal executing a run of protocol from the role in the protocol, and inferring a principal's knowledge from the local observations of the principal. And we show analytically and empirically that this model can be easily reduced to Satisfiability (SAT) problem and efficiently implemented by a modern SAT solver. 相似文献
79.
Yifei Wang Shouying Huang Xinsheng Teng Hongyu Wang Jian Wang Qiao Zhao Yue Wang Xinbin Ma 《Frontiers of Chemical Science and Engineering》2020,14(5):802
The Fischer–Tropsch synthesis (FTS) continues to be an attractive alternative for producing a broad range of fuels and chemicals through the conversion of syngas (H2 and CO), which can be derived from various sources, such as coal, natural gas, and biomass. Among iron carbides, Fe2C, as an active phase, has barely been studied due to its thermodynamic instability. Here, we fabricated a series of Fe2C embedded in hollow carbon sphere (HCS) catalysts. By varying the crystallization time, the shell thickness of the HCS was manipulated, which significantly influenced the catalytic performance in the FTS. To investigate the relationship between the geometric structure of the HCS and the physic-chemical properties of Fe species, transmission electron microscopy, X-ray diffraction, N2 physical adsorption, X-ray photoelectron spectroscopy, hydrogen temperature-programmed reduction, Raman spectroscopy, and Mössbauer spectroscopy techniques were employed to characterize the catalysts before and after the reaction. Evidently, a suitable thickness of the carbon layer was beneficial for enhancing the catalytic activity in the FTS due to its high porosity, appropriate electronic environment, and relatively high Fe2C content. 相似文献
80.
Ruoshi Peng Shengrui Xu Xiaomeng Fan Hongchang Tao Huake Su Yuan Gao Jincheng Zhang Yue Hao 《半导体学报》2023,(4):90-95
The nano-patterned InGaN film was used in green InGaN/GaN multiple quantum wells(MQWs) structure, to relieve the unpleasantly existing mismatch between high indium content InGaN and GaN, as well as to enhance the light output. The different self-assembled nano-masks were formed on InGaN by annealing thin Ni layers of different thicknesses. Whereafter,the InGaN films were etched into nano-patterned films. Compared with the green MQWs structure grown on untreated InGaN film, which on nano-patterne... 相似文献