查询词典 sic

Pyrolytic carbon coating and successive SiC matrix were respectively prepared by chemical vapor infiltration in T700 kind integer felt. The subsequent reactive melt infiltration method was adopted to densify it further and C/SiC composites were successively prepared. The microstructure and effect of interface on flexural properties were thoroughly investigated.

摘 要：以T700炭纤维准三维编织针刺整体毡为预制体，在炭纤维表面CVI预沉积热解炭涂层，利用化学气相渗透-反应熔体浸渗法制备C/SiC复合材料，观察材料的微观形貌，并探讨界面对弯曲性能的影响。

The experimental results showed that SiC ultrafine powder was synthesized at 1500℃for 120 minutes by used rare earth lanthanum as additive. Its primary particle size was about 100nm and aggregated particle size was about 360nm and the particle shape was regulation, non-aggregation and well dispersibility. While the rare earth ceria used as the additive, SiC ultrafine powder was synthesized at 1500℃for 150 minutes but the particle shape was irregulation and seriously agglomerated and had numerous crystal whiskers.

实验结果表明：以稀土镧为添加剂时，在1500℃×120min合成工艺下，可以合成出一次粒径为100nm左右，二次粒径为360nm的SiC细粉，且SiC粉体颗粒形状规则，无团聚，分散性好；以稀土铈为添加剂时，在1500℃×150min合成工艺下，也可以得到单相的SiC，但SiC粉体颗粒形状不规则，有大量晶须存在，且团聚严重。

Hot isostatically pressed nano-ceramics of monophasic SiC and Si3N4/SiC composite were studied,and the phase composition and ndcrostructure were characterized by XRD, TEM and HREM.

采用高温等静压工艺，制备了纳米结构的单相SiC及Si3N4／SiC复相陶瓷，并通过X射线衍射分析、透射及高分辨电镜对其相组成及结构进行了表征。

After Pressureless Sintering the densification behaviour of the SiC-based powder mixtures was observed to be markedly dependent not only on the type and amount of sintering aids used, but also on the crystal structure of the SiC powder.

经过常压烧结致密化行为的碳化硅基粉末混合物被观察到明显不仅仅取决于类型和数量烧结助剂使用，而且也影响到晶体结构的碳化硅粉末。

This paper is the fourth section of the serial articles, it's primary contents included: based on the basic theory of the continuous medium mechanics, we have given rotational dynamical equations of the solid inner core of the Earth, taken into account influence of the self\|gravitational potential, of the fluid pressure acting on the instantaneous surface of the SIC, and of the degree 2 tesseral component of the tidal generating potential on the rotation of SIC, and has presented their practical expression, in order of magnitude of O.

中国科学院国家天文台/云南天文台，昆明 650011；2。徐州师范大学物理学系，徐州 221116；3。中国科学院测量与地球物理研究所，武汉 430077摘要：本文是序列文章的第四篇，其内容包括：基于连续介质力学的基本理论，给出了固体外核自转的动力学方程，考虑了地球的自引力、液核对内核边界的压力和二阶外部引潮力位对SIC自转的影响，并在O的量级上给出了其实用的表达式。

The main damage form of SiC coatings is transcrystalline rupture, the damage degree is depended on the size of SiC crystalline.

经D〓离子辐照后与未辐照的PG相比，不仅其CS产额要高1.6倍，而且其发生CS的温度区域要宽200K左右。

The effective channel mobility of4H-SiC MOSFETs is increased significantly by high temperature anneals in nitric oxide.4H-SiC MOSFET with hydrogen postoxidation annealing has a lower threshold voltage of3.1V and a wide gate voltage operation range in which the inversion channel mobility is more than100cm 2 /Vs.

SiC的雪崩击穿电场是Si的十倍，因此，理论上SiC单极功率器件的导通电阻可以比Si器件的低400倍，但在6H-SiCMOS结构中，由于反型层的电子迁移率较小，沟道迁移率测量值仅为40～50cm2/Vs，远远低于6H-SiC的体迁移率400cm2/Vs眼1熏2演，限制了SiC功率MOSFET的导通电阻Ron。

An investigation of Au/Ti/Ni and Au/Ti/Pt ohmic contacts to n-type 4H-SiC and the behavior of metal films on SiC with thermal anneals is reported.

研究了热退火条件下Au/Ti/Ni-4H-SiC欧姆接触形成机制。

By contrast with the conventional 3C-SiC growth on carbonized Si, we found that SiC on AlN/Si has hexagonal structure.

我们发现与传统的通过Si衬底表面碳化只能获得立方相不同，在AlN/Si上所生长的SiC具有六方相结构。

The results show that the films are characterized by the amorphous microstructure and mainly composed of Si C bondings, C C bondings as well as a small mount of oxide impurity consorted with Si; the content of the C C bondings decreased after annealing in vacuum, meanwhile the Si C bondings content increased, annealing in vacuum is beneficial to the formation of SiC; after annealing at 800 in air, a thin dense layer of SiO2 formed on the surface, which prevented the oxygen from contacting with the film and effectively protected the inner SiC from oxidizing.

结果表明，薄膜主要以非晶为主，由Si--C键， C--C键和少量Si的氧化物杂质组成；在真空条件下经高温退火后，薄膜C--C键的含量减少，而Si--C键的含量增加，真空退火有利于SiC的形成；在800℃空气中退火后，薄膜表面生成一层致密的SiO2薄层，阻止了氧气与薄膜内部深层的接触，有效保护了内部的SiC。

So it was last week in Selma , alabama.

上星期在亚拉巴马州塞尔马市发生的事件也是这样一个转折点。

The group also spearheads various social programs in China.

该组织还带头参与中国的各种社会活动。