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61.
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Yuping Liu Jinli Yu Yongfeng Lun Yawen Wang Yi Wang Shuqin Song 《Advanced functional materials》2023,33(44):2304184
Metal nanoclusters (MNCs) are compositionally well-defined and also structurally precise materials with unique molecule-like properties and discrete electronic energy levels. Atomically precise ligand-protected Cu nanoclusters (LP-CuNCs) are one category of typical MNCs that usually demonstrate unique geometric and electronic structures to serve as electrocatalysts. However, the synthesis, application, as well as structure-performance relationship of LP-CuNCs are not adequately studied. Significantly, the ligands are essential to the geometric structure, crystal structure, size, and electronic structure of LP-CuNCs, which determine their physiochemical properties and applications. In this review, significant progress in the ligand design of LP-CuNCs, and their application in electrocatalytic reactions is introduced. The general basics of ligand-protected MNCs (LP-MNCs) are first introduced and the functions of ligands are emphasized. Subsequently, a series of different ligands for LP-CuNCs including thiolates, phosphines, alkynyl, polymers, and biomolecules are highlighted. Thereafter, their applications in different electrocatalytic reactions are discussed. It is believed that this review will not only inspire the design and synthesis of novel LP-CuNCs, but also contribute to the extension of their applications in electrocatalytic reactions and the establishment of accurate structure-performance relationships. 相似文献
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Development of Highly Functional Biomaterials by Decoupling and Recombining Material Properties 下载免费PDF全文
65.
为了研究环氧树脂的不同长度脂肪链结构因素对其固化动力学和固化物性质的影响,合成了两种以萘环结构为分子骨架,以酯键链接两条对称的柔性脂肪链结构的环氧树脂,并通过核磁共振氢谱(1 H NMR)和元素分析(EA)对其结构进行了表征。以DDM为固化剂通过Ozawa法计算出R1/DDM和R2/DDM固化体系的反应活化能Ea分别42.34kJ/mol和56.88kJ/mol,并且发现具有长链结构的R1对固化反应有一定的阻碍作用,而短链结构的R2对固化体系有一定的自催化作用。对固化物的热稳定性、玻璃化转变温度(Tg)、拉伸强度、弯曲强度和吸水率进行了测试,研究了它们之间的构效关系。研究结果表明随着环氧树脂脂肪链长度的增加,其固化物的耐热性、玻璃化转变温度和吸水性下降,而力学性能得到了提高。 相似文献
66.
Why would people use Short Message Service (SMS) to say something they would not say in person? There is a trend that SMS is becoming more and more popular because it facilitates more extended modes of communications. Using technology acceptance model, we hypothesize the attitude of SMS would be influenced by its perceived effectiveness for communications, perceived ease of use, and subjective norm. Besides the special aspects of communications, conflict avoidance and privacy protection will enforce the impact of perceived effectiveness of SMS for communication. We investigated 953 SMS users and the results support most of our hypotheses. Furthermore, our analyses also show there are differences between females and males on the influence mechanism behind their attitude towards SMS. 相似文献
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Most studies on the role of IT for economic exchange predicted that under a given set of exchange attributes buyers would choose a certain mode of relationship with suppliers. Our study of an online IT services marketplace revealed that buyers do not have a single, uniformly preferred type of relationship, but rather maintain a portfolio of relationships. Furthermore, different buyers arrange their portfolios of exchange relationships in different ways. We found four clusters of buyers' portfolios of relationships labeled Transactional buyers, Recurrent buyers, Small diversifiers and Large diversifiers, that differ in their usage of auction or negotiation mechanism, their supplier relations as well as their usage of preferred suppliers. Our results thus paint a richer picture of how buyers organize their supplier networks online. 相似文献
69.
The alarming growth rate in the online game industry calls for a need of understanding the determinants of online gamers’ behaviour. Investigating how online gamers choose different online characters assists online game vendors to design characters that match the needs of different online gamers. Recently, numerous online game designers have introduced celebrity figures as characters for certain online games. The popularity of those celebrities has resulted in greater awareness of these games, and hopefully further increases the playability of online games. While different online gamers are motivated by different desires for playing, it is insufficiently researched whether these online celebrity characters have actually altered players’ choice in giving preference to these games. Thus, this study conducts an experimental design to study the reasons behind players’ choice of characters by studying how online games perceive the interpersonal attractiveness of celebrity online characters, and how online gamers with different playing motivations display different behaviours in their choice of online game characters. Results from the survey filled out by participants after the experiments show that the attractiveness of celebrity online characters is significantly higher than that of non-celebrity characters. Further, online game players with a social playing motivation tend to choose celebrities as their online game characters. 相似文献
70.
Hidetsugu Nanba Natsumi Anzen Manabu Okumura 《International Journal on Digital Libraries》2008,9(2):151-161
The need for academic researchers to retrieve patents and research papers is increasing, because applying for patents is now
considered an important research activity. However, retrieving patents using keywords is a laborious task for researchers,
because the terms used in patents for the purpose of enlarging the scope of the claims are generally more abstract than those
used in research papers. Therefore, we have constructed a framework that facilitates patent retrieval for researchers, and
have integrated research papers and patents by analysing the citation relationships between them. We obtained cited research
papers in patents using two steps: (1) detection of sentences containing bibliographic information, and (2) extraction of
bibliographic information from those sentences. To investigate the effectiveness of our method, we conducted two experiments.
In the experiment involving Step 1, we prepared 42,073 sentences, among which a human subject manually identified 1,476 sentences
containing citations of papers. For Step 2, we prepared 3,000 sentences, in which the titles, authors, and other bibliographic
information were manually identified. We obtained a precision of 91.6%, and a recall of 86.9% in Step 1, and a precision of
86.2% and a recall of 85.1% in Step 2. Finally, we constructed an information retrieval system that provided two methods of
retrieving research papers and patents. One method was retrieval by query, and another was from the citation relationships
between research papers and patents. 相似文献