S.Q. Li
,
J.I. Dickson and J.P. Bailon (Central Iron and Steel Research Institute (CISRI)
,
Beijing 100081
,
China)(Ecole Polytecnique de Montreal
,
Montreal H3C 3A7
,
Canada)
金属学报(英文版)
The microfractography of transgranular stress corrosion cracking (TSCC) of 70Cu-30Zn a-brass in ammoniacal solution was studied. The observations indicate that on a very microscale, the crack path of TSCC of or-brass follows {111} planes. The crack path very often alternates between {111} Planes to result in "cleavage-like"facet, the usual average orientation of which is {110} with preferential microscopic crack propagation in (100) and (112) directions. The average orientation of wide secondary facets is often close to {100}. The size of {111} microfacets increases with incrmsing stress intensity K, which indicates that the microscopic crack path follows {111} planes on which some localized slip has occurred. Possible TSCC mechanisms which appear to be consistent with the microfraphic features observed in the present study are also discussed.
关键词:
fractography
,
null
,
null
,
null
吴历斌
,
黄富强
,
江莞
无机材料学报
doi:10.3724/SP.J.1077.2009.00427
利用结构功能区思想的导电功能区和透光功能区,提出了层状p型Cu/Q透明导体的设计模型. LaCuOTe和Sr3Cu2Sc2O5S2因结构层[Cu2Te2]和[Cu2S2]对应导电功能区、[La2O2]和[Sr3Sc2O5]对应透光功能区,符合模型设计思想,是兼具高导电性和高透光性的透明导体,光谱和电导等验证了模型设计p型透明导体的可行性和正确性. 从功能区角度,改变LaCuOS中导电功能层([Cu2S2]→[Cu2Te2])可显著提高材料导电性(10-3S/cm→100S/cm);替换LaCuOTe中透光功能层([La2O2]→[Sr3Sc2O5])能可控改善材料透光性(2.3eV→3.1eV).
关键词:
p型Cu/Q
,
透明导体
,
导电率
,
层状结构
,
结构功能区
姜奉华
,
徐德龙
硅酸盐通报
doi:10.3969/j.issn.1001-1625.2004.06.006
通过研究Q相与C2S和Q相与C4AF的共存条件,构造Q相-C2S-C4AF水泥系统,对此系统水泥形成条件进行研究.研究表明:Q相与C2S和Q相与C4AF能够共存,可以组成Q相-C2S-C4AF-C12A7水泥系统.在Q相-C2S-C4AF-C12A7水泥系统中,Q相在1270℃开始生成,随着温度的升高,Q相的生成量逐渐增大;采用V2O5对β-C2S具有较好的稳定作用.随着C4AF量的增加,Q相的量也在增加,同时,烧成温度降低.
关键词:
Q相
,
Q相-C2S-C4AF水泥
,
形成条件
,
抗压强度
Energy & Environmental Science
We report the template-directed synthesis of sulphur-carbon nanotubes and their use to form a membrane that is binder-free, highly conductive and flexible. This nanostructured membrane is used as a self-supporting cathode without metal current-collectors for Li-S batteries. The membrane cathode has a high electrical conductivity and renders a long life of sulphur of over 100 charge-discharge cycles. High discharge capacity of sulphur was attained at 712 mA h g(sulphur)(-1) (23 wt% S) and 520 mA h g(sulphur)(-1) (50 wt% S) at a high current density (6 A g(sulphur)(-1)). The overall capacity of the flexible cathode correspondingly reaches 163 mA h g(-1) (23 wt% S) and 260 mA h g(-1) (50 wt% S). These results demonstrate the great potential of this nanostructured flexible membrane as a cathode for Li-S batteries with fast charge-discharge performance and long life.
关键词:
rechargeable lithium batteries;positive electrode materials;cell;temperature;composites;capacity;oxide
张曼
,
陈朝轶
,
李军旗
,
赵聪
,
杨夏琼
表面技术
doi:10.16490/j.cnki.issn.1001-3660.2015.08.016
目的:研究在含S2-的铝酸钠溶液中Q235钢的腐蚀行为。方法模拟生产条件配制种分母液,采用盐雾腐蚀实验与SEM和EDS分析技术,结合腐蚀质量损失动力学方程与极化曲线,研究Na2 S质量浓度与时间对Q235钢腐蚀行为的影响。结果腐蚀产物元素主要为O,S,Al,Fe。在铝酸钠溶液中,基体的表面会覆盖一层Al2 O3保护膜,可以阻碍溶液中的硫离子穿透到基体表面,对基体起到一定的保护作用。因此腐蚀初期及低质量浓度下,腐蚀速率缓慢;但随着质量浓度的增加、腐蚀时间的延长,保护膜被破坏,S2-穿过保护膜与基体反应,生成硫化物加速了腐蚀速率;当S2-质量浓度增加到6 g/L,腐蚀时间为9 d时,硫化物被氧化成具有较稳定结构的氧化物,腐蚀被抑制。结论在铝酸钠溶液中,S2-质量浓度及腐蚀时间对腐蚀有一定的促进作用,但当腐蚀时间及S2-质量浓度达到一定值时,腐蚀速率呈现减小的趋势,腐蚀被抑制。
关键词:
铝酸钠溶液
,
Q235
,
Na2 S质量浓度
,
腐蚀时间
,
腐蚀速率
,
极化曲线