G.K.R.Senadeera
,
J.M.R.C.Fern
材料科学技术(英文)
Substituted thiophene sensitized, nanocrystalline TiO2-based quasi solid-state solar cells were fabricated by using either poly (3-thiophene acetic acid) (P3TAA) or a copolymer with poly (3-thiophene acetic acid)-poly (hexyl thiophene) (P3TAA-PHT) polymers and copper iodide (CuI) as a hole conducting material together with an ionic liquid 1-ethyl-3-methylimidazolium bis (trifluoromethylsulfonyl) amide and lithium bis (trifluoromethanesulfone) imide as additives for charge transport promotion. Dramatic enhancements in the cell performances were observed with the additives in CuI. While the cell sensitized with P3TAA generated a short-circuit photocurrent of ~1.45 mA•cm-2, an open-circuit photovoltage of ~345 mV with a total power conversion efficiency of ~0.3% under simulated full sunlight of 100 mW•cm-2 (air mass: 1.5), the cell sensitized with copolymer P3TAA-PHT delivered ~0.25% efficiency under the same conditions with ~1.23 mA•cm-2 as photocurrent and ~371 mV as photovoltage.
关键词:
Solar cells
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cells
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polymers
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titanium
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dioxide
H.P. Chen and Z.J. Deng (State Key Lab. for Mechanical Behavior of Materials
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Xi'an Jiaotong University
,
Xi'an 710049
,
China)
金属学报(英文版)
The effect of specimen thinkness on JR resistance curve has been investigated using low and middle strength steels. As the J dominance regime is reached, the initial J-integral values, J(i), are definite even if the elastic component Ji(e) and plastic component Ji(p)vary with the thinkness of specimen. The wider the specimen width, the larger the Ji(e)/Ji and the smaller the Ji(p)/Ji. The crack propagation resistance, dJR/da and dJp/da, decreases, while dJe/da increases linearly with increasing specimen thinness.Based on the above experimental results, an empirical formula dJ/da = α+β. B is given, which can be used to evaluate the safety of practical structural components.A modified J-integral is presented, upon which a new view is Put forward that the increase in crack growth resistance is induced mainly by the increase in the plastic J-integral component with the crack propagation,
关键词:
: fracture mechanics
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null
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null
,
null
惠雪梅
,
王晓洁
,
尤丽虹
,
王益
,
全小平
宇航材料工艺
doi:10.3969/j.issn.1007-2330.2006.z1.011
通过地面环境模拟实验,分析了高模碳纤维/环氧树脂改性氰酸酯复合材料(M40J/CE/EP)的表面元素,研究了高真空加热环境下复合材料的真空出气性能和出气气体成分.结果表明,M40J/CE/EP复合材料的表面主要由C、O、N元素构成;经高真空加热后,复合材料的出气气体成分以小分子挥发物和碳氢化合物电离碎片为主,有可能在空间低温条件下冷凝在航天器的敏感器件表面而造成污染;通过真空出气性能实验测得,M40J/CE/EP复合材料的总质量损失(TML)的平均值为0.27%,收集到的可凝挥发物(CVCM)为0,完全达到出气筛选合格的指标要求.
关键词:
氰酸酯树脂
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复合材料
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出气
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X射线光电子能谱
Solid State Communications
Samples with composition R2Fe14M3 (M = Ga and Si; R = Y, Nd, Sm, Gd, Tb, Dy, Ho, Er and Tm) have been prepared by are-melting. Crystal-structure studies have shown that the prepared samples are single phase with the rhombohedral Th2Zn17 and/or the hexagonal Th2Ni17 structure. Substitution of Ga for Fe in R2Fe17 leads to an increase of the unit-cell volume, whereas Si substitution reduces the unit-cell volume. The Curie temperatures of the R2Fe14Ga3 and R2Fe14Si3 compounds are much larger than those of the corresponding R2Fe17 compounds. The Fe moment decreases upon Ga or Si substitution. The compounds R2Fe14Ga3 and R2Fe14Si3 With R = Er and Tm exhibit a spin-reorientation transition at low temperature. (C) 1997 Elsevier Science Ltd.
关键词:
neutron-diffraction;solid-solutions;substitution;anisotropy;nd2fe17
孙银洁
,
胡胜泊
,
李秀涛
宇航材料工艺
doi:10.3969/j.issn.1007-2330.2010.02.027
利用SEM、TEM、XPS、XRD、Raman和元素分析仪分析了M40J和T300的表面化学、物理及微观结构特征.研究发现:M40J含碳量高于T300纤维,而含氮量低于T300纤维,且表面活性基团比T300纤维低;M40J和T300碳纤维表面具有大量沟槽,前者相对长而浅,后者相对短而深;T300纤维端面皮芯结构明显,而M40J端面结构较均匀;M40J的微晶结构及取向性优于T300碳纤维.
关键词:
M40J碳纤维
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微观结构
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化学特征
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物理特征
韩建平
,
秦滢杰
,
高伟
,
刘新东
宇航材料工艺
doi:10.3969/j.issn.1007-2330.2014.05.010
针对卫星构件的不同需求,开发了一种芳香胺固化的环氧树脂BA204.研究了无溶剂及溶剂法成型的M40J/BA204复合材料力学、真空放气性能和管件在模拟温度交变条件下的性能变化情况.结果表明:两种方法制备的复合材料力学性能均能满足卫星构件要求,无溶剂法制备的复合材料力学性能优于溶剂法.采用无溶剂法制备的M40J/BA204复合材料其真空质损率为0.23%,可收集挥发性凝聚物为0.009%;复合材料管件经200次热循环冲击后力学性能变化不大,表明M40J/BA204复合材料具有良好的热稳定性.
关键词:
卫星构件
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M40J/BA204复合材料
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纤维缠绕
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无溶剂法
田仲良
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姜森宝
,
陈正宗
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包汉生
,
刘正东
钢铁研究学报
doi:10.13228/j.boyuan.issn1001-0963.20160043
研究了新型汽轮机转子用C700R-1耐热合金700℃长期时效组织和性能的演变.研究表明:合金的主要析出相为 M23 C6、MC、γ′.C700R-1合金长期时效组织结构稳定,时效5000 h 晶界处 M23 C6碳化物平均宽度从190 nm增加至240 nm,呈不连续状态分布;时效5000 h球形γ′平均直径从22.0 nm粗化至49.8 nm,粗化速率缓慢.合金拉伸强度和硬度随时效时间延长先快速升高,后缓慢降低,并逐渐趋于稳定;理论计算 C700R-1合金中γ′临界尺寸为29.8 nm;长期时效后合金的冲击值在50 J 以上.
关键词:
汽轮机转子
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C700R-1 耐热合金
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组织演变
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性能演变
阴强
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李爱菊
,
王威强
,
王彦明
,
王欣
硅酸盐通报
doi:10.3969/j.issn.1001-1625.2005.04.023
以石墨与酚醛树脂粉料为原料,通过热模压成形得到一种R/C复合材料.研究了质量分数为20%~30%酚醛树脂对复合材料导电、力学以及阻气性能的影响;并利用SEM分析了不同酚醛树脂含量复合材料的断口和表面形貌.结果表明,随酚醛树脂含量的增加,能够使复合材料的抗弯强度、冲击强度和电阻率明显提高,而密度先上升后下降.试验中,当酚醛树脂质量分数为22.5%时,R/C复合材料的阻气性最好,此时抗弯强度、冲击强度、电阻率和密度分别为45.5MPa,8.9J/cm2,169.3×10-6Ω·m和1.93g/cm3,其值达到或超过国内外同类研究水平.
关键词:
石墨
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酚醛树脂
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复合材料
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性能