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排序方式: 共有2706条查询结果,搜索用时 187 毫秒
91.
Organic Electronics: Facile Photo‐Crosslinking of Azide‐Containing Hole‐Transporting Polymers for Highly Efficient,Solution‐Processed,Multilayer Organic Light Emitting Devices (Adv. Funct. Mater. 48/2014) 下载免费PDF全文
Junwoo Park Changyeon Lee Jihye Jung Hyunbum Kang Ki‐Hyun Kim Biwu Ma Bumjoon J. Kim 《Advanced functional materials》2014,24(48):7776-7776
92.
Yuriy N. Luponosov Jie Min Tayebeh Ameri Christoph J. Brabec Sergei A. Ponomarenko 《Organic Electronics》2014,15(12):3800-3804
A new linear dithienosilole-based oligothiophene end-capped with methyl and electron-withdrawing dicyanovinyl groups, DTS(Oct)2-(2T-DCV-Me)2, was prepared in good yield. This oligomer exhibited broad absorption spectra in bulk down to the near-IR region with the optical edge at 900 nm, resulting in an initially high power conversion efficiency of 5.44% in solution-processed organic solar cells using PC71BM as an acceptor. 相似文献
93.
第二次土地调查权属调查与地类调查因各类原因不一定完全吻合,为保证各级行政界限与图斑边界的一致,本文提出以最底层地类图斑为基准,参考各级行政界限进行调整,在保证县级界线不变的情况下,兼顾数据整理效率,实现了各级行政区与地类图斑边界的套合。 相似文献
94.
《Signal Processing: Image Communication》2014,29(10):1158-1170
Encrypting regions of interest in H.264/AVC and SVC bit streams after compression is a challenging task due to drift. In this paper, we assess whether the use of slice groups makes this task easier and what its expense in terms of bit rate overhead is. We introduce the concept of all-grey base layers for SVC which simplify the encryption of regions of interest in surveillance camera applications while obeying all standard-imposed base layer restrictions. Furthermore, we show that the use of slice groups is possible with relatively low overhead for medium and high bit rates (below 5% in most of the tested configurations). This applies to H.264/AVC as well as SVC bit streams with two and three spatial layers, including those with the newly introduced all-grey base layers. Although we are able to contain spatial and inter-layer drift with our proposed encryption setup, temporal drift still remains an issue that cannot be solved by sole usage of slice groups. 相似文献
95.
96.
Dramatic Inversion of Charge Polarity in Diketopyrrolopyrrole‐Based Organic Field‐Effect Transistors via a Simple Nitrile Group Substitution 下载免费PDF全文
97.
98.
Iron incorporated into food systems induces oxidation and precipitation. The consequences are reduced bioavailability and a functional modification of other food components such as proteins. The iron-chelates such as ferrous bisglycinate represent a possibility to avoid side effects, since the iron is protected. The aim of this study is to investigate the effects of iron-chelates compounds on the properties of an oil/water interface stabilized by caseinate or β-lacotoglobulin, under environmental conditions at 20 °C. Analyses were performed using dynamic drop tensiometry during 5000 s. The aqueous bulk phase is an imidazole/acetate buffer (0.1 M), containing 0.4 × 10−6 M protein, and 0.2 × 10-6 9 M iron-chelates compounds. The results indicate that, under neutral conditions, the addition of some irons salts (NaFe-EDTA or Fe-bisglycinate) do not change the structure of the interface stabilized by a protein containing no phosphate groups (β-lactoglobulin). In the case of caseinate, NaFe-EDTA addition increases the lowering rate of surface tension at pH 6.5. On the contrary, the lowering rate of surface tension with caseinate is inhibited by Fe-bisglycinate at pH 6.5. Such an effect is not observed with β-lactoglobulin. The low transfer of irons ions from the bulk to the interface stabilized by β-lactoglobulin is confirmed by zetameter and FTIR measurements. These results indicate an effective strategy to follow for controlling the physical and chemical stability of an emulsion stabilized with proteins. 相似文献
99.
Effects of incorporation of ionic groups and ionic interactions to a model polypeptide, poly(γ-benzyl-L-glutamate) (PBLG), are studied. Partial conversion of γ-benzyl-L-glutamate residues to glutamic acid residues does not change molecular conformation (α-helix) and shows little change in properties. By contrast, partial conversion to sodium glutamates (ionic groups) leads to conversion from a rigid rod to a semi-flexible rod at low ion contents and causes significant changes in thermal stability and birefringence. In solution, lyotropic liquid crystalline behavior of PBLG is lost at ion content as low as 3.2 mol %. In solid, birefringence is still observed at this ion content, suggesting thermotropic liquid crystallinity of this ionic PBLG. Molecular composites made of ionic PBLG as a reinforcer and poly(4-vinylpyridine) (PVP) as a matrix polymer show significant enhancement in strength and toughness as a result of ion-dipole interactions between the component polymers. 相似文献
100.
地铁空间中导向标识系统的无障碍设计研究 总被引:1,自引:0,他引:1
以西安地铁二号线导向标识的实际科研项目为依托,通过分析各类有障碍群体乘坐地铁时的生理、心理特征,研究其在地铁空间行为流程下的节点标识,最后提出无障碍导向标识的具体可操作技术、方法、设置点位及信息内容.这一针对弱势群体的无障碍标识设计的研究,对完善地铁空间导向标识系统的完整性和科学性来说具有一定的参考价值和意义. 相似文献