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排序方式: 共有585条查询结果,搜索用时 125 毫秒
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Two lignite samples, Beulah No. 3 and Big Brown No. 1, were liquefied at 420 °C using H2 and synthesis gas to determine the optimum beneficial amount of H2S in the batch autoclave reactor. Under the conditions employed, 50–100 psi partial pressure of H2S, nominally 4–10 wt% of daf lignite, was optimum for both samples. Synthesis gas outperformed H2 with and without H2S for the liquefaction of the two coals. 相似文献
3.
链烷烃的表面张力与内压 总被引:1,自引:0,他引:1
对Davis和Rosseinsky提出的关系检验表明,液体的表面张力σ与P1Vm1/3之比不仅取决于温度,还与液体的种类有关,据此,建立了一个能由链烷烃的分子结构准确预测其表面张力的方法。 相似文献
4.
目前SET协议在电子商务交易中应用越来越广泛,因此,对SET协议的安全性的要求就越来越高。论文在SET协议的交易流程基础上,分析了其安全机制采用的技术和优点,指出了SET协议安全性存在的一些问题。 相似文献
5.
Hongfang Sun Zewen Liu Jiahao Zhao Li Wang Jing Zhu 《IEEE transactions on magnetics》2007,43(8):3457-3461
A low-temperature annealing process in vacuum is proposed to enhance the inductance of RF inductors with FeNi-SiO2 magnetic granular films. Due to the great improvement of soft magnetic property in the 200degC and 350degC annealed film, the inductance is enhanced by 9.6% (200degC) and 8.3% (350degC), respectively, compared with the case of as-deposited film inductor. The peak value of quality factor, which is 9.18 for the as-deposited film inductor, is also increased to 9.27 (200degC ) and 12.27 (350degC), respectively. 相似文献
6.
摩擦诱发高铬铸铁相变的透射电镜研究 总被引:2,自引:0,他引:2
利用透射电子显微镜研究了高铬铸铁在摩擦过程中的显微组织变化。结果表明:奥氏体基体在摩擦应力的作用下发生相变。摩擦表面形成α‘M。次表层形成γ与α’M共存区;γ与.ε共存区;γ位错丛聚区。 相似文献
7.
8.
Zewen Chen Zhenhua Wang Boxiang Wang Juntang Yuan Lei Huang Zengbin Yin 《International Journal of Applied Ceramic Technology》2021,18(6):2010-2019
In this study, WC-8Co cemented carbides were prepared by spark plasma sintering. When the samples sintered at 1300℃ were cooled to room temperature, the samples were sintered multiple times at 1250℃. The changes in microstructure and mechanical properties of WC-8Co cemented carbides prepared by multiple spark plasma sintering were studied. The hardness of cemented carbides increased in the first two sintering, reaching 16.5 GPa. However, the hardness decreased seriously in the last two sintering. The attenuation rates of hardness were 6.2% and 2.5% due to the abnormal coarse grains. Furthermore, the crack path along the grain boundary was almost straight, causing a decrease in the indentation fracture toughness of cemented carbides. Additionally, the grains of cemented carbides were abnormally coarsened, and the morphologies of grains became unstable due to multiple sintering. 相似文献
9.
设计了面向圆片级封装的一种闭环加速度计读出电路.在基于电容式微加速度计结构的读出电路设计中考虑了寄生电容对整个系统的影响.用MATLAB SIMULINK对所设计的读出电路进行了建模仿真.在仿真过程中分析了噪声、圆片级封装与普通封装的寄生参数及实际工艺中流水结构的不对称性的影响并进行了比较.结果表明,所设计传感器及读出电路的非线性误差在量程±20 gn范围内小于0.5%;圆片级封装的稳定时间在2 ms,小于普通封装的稳定时间;基于圆片级封装的对称性梳齿结构的输出电压灵敏度为328 mV/gn. 相似文献
10.
Yixuan Jia Christoph A. Spiegel Alexander Welle Stefan Heißler Elaheh Sedghamiz Modan Liu Wolfgang Wenzel Maximilian Hackner Joachim P. Spatz Manuel Tsotsalas Eva Blasco 《Advanced functional materials》2023,33(39):2207826
Manufacturing programmable materials, whose mechanical properties can be adapted on demand, is highly desired for their application in areas ranging from robotics, to biomedicine, or microfluidics. Herein, the inclusion of dynamic and living bonds, such as alkoxyamines, in a printable formulation suitable for two-photon 3D laser printing is exploited. On one hand, taking advantage of the dynamic covalent character of alkoxyamines, the nitroxide exchange reaction is investigated. As a consequence, a reduction of the Young´s Modulus by 50%, is measured by nanoindentation. On the other hand, due to its “living” characteristic, the chain extension becomes possible via nitroxide mediated polymerization. In particular, living nitroxide mediated polymerization of styrene results not only in a dramatic increase of the volume (≈8 times) of the 3D printed microstructure but also an increase of the Young's Modulus by two orders of magnitude (from 14 MPa to 2.7 GPa), while maintaining the shape including fine structural details. Thus, the approach introduces a new dimension by enabling to create microstructures with dynamically tunable size and mechanical properties. 相似文献