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991.
Metal–Organic Frameworks: Biomimetic Replication of Microscopic Metal–Organic Framework Patterns Using Printed Protein Patterns (Adv. Mater. 45/2015) 下载免费PDF全文
992.
基于常被忽略的爆炸荷载对邻近巷道背爆侧围岩缺陷的扰动问题,采用爆炸加载数字激光动态焦散线试验系统,探究了爆炸荷载作用下邻近巷道背爆侧不同倾角裂纹缺陷的扩展规律。试验结果表明:爆炸荷载作用下,直墙拱形巷道背爆侧倾角θ=30o(逆时针方向为正)的预制裂纹最终扩展位移最大,之后随着倾角增大或者减小,裂纹扩展位移均逐渐减小;弧形断面对应力波的削弱作用小于矩形断面,这导致斜向上预制裂纹扩展位移为关于水平方向对称的斜向下裂纹的2~3倍;能量释放率对裂纹的扩展具有驱动效应,且其随时间基本呈现先振荡增加达到峰值,然后振荡减小为零的规律,但这种振荡幅度随裂纹最终扩展位移的减小而变小。上述的研究为邻近巷道背爆侧经济安全合理的支护提供了理论依据。 相似文献
993.
Using the structural equation modeling method (N = 811), this study explores the structural relationships among online news consumption, political participation and social trust, with a focus on the mediating effects of online users’ deliberative perceptions and news-related online interactive activities. The analysis confirms that users’ perceptions of online deliberation exert a significant mediating effect on users’ levels of news consumption, political participation, and social trust. Users’ interactive civic messaging behaviors, on the other hand, solely enhance participatory intentions. The findings also show that the consumption of political news and the consumption of entertainment news have different effects on users’ perceptions of online deliberation, social trust, and political participation. Specifically, while political news has a direct and relatively strong influence on participation, entertainment news has a limited and indirect effect on participation. Online interactive activities are negatively associated with users’ perceived competency for online deliberation. Further implications of the study are also discussed. 相似文献
994.
995.
N.?PrietoEmail author M.?L.?Swift S.?T.?Summerfelt M.?Juárez R.?T.?Zijlstra J.?L.?Aalhus 《Food Analytical Methods》2015,8(10):2660-2664
Some species of actinomycetes, fungi, and blue-green algae produce semivolatile off-flavor compounds responsible for earthy-musty odorants in water from aquaculture facilities and tend to bioaccumulate within fish flesh. Although these off-flavor compounds are harmless to human health, high levels within fish tissue lead to an undesirable taste leading to an unmarketable consumption quality. Preharvest processes such as depuration can be used to eliminate most of these off-flavor compounds and ultimately enhance salmon quality. This study examined the potential of near infrared spectroscopy (NIRS) to discriminate depurated from nondepurated salmon fillets (n?=?62). Partial least squares discriminant analysis based on NIR spectra correctly classified 100 % of non-depurated and depurated salmon fillets. The successful classification was likely a consequence of statistically significant differences in the content of off-flavor compounds between both samples, which could have been detected by NIR spectra. Thus, NIRS is a fast, inexpensive, solvent-free, and non-destructive technology that can be used for the authentication of salmon with enhanced quality for marketing purposes. 相似文献
996.
997.
Materials and Wireless Microfluidic Systems for Electronics Capable of Chemical Dissolution on Demand 下载免费PDF全文
Chi Hwan Lee Jae‐Woong Jeong Yuhao Liu Yihui Zhang Yan Shi Seung‐Kyun Kang Jeonghyun Kim Jae Soon Kim Na Yeon Lee Bong Hoon Kim Kyung‐In Jang Lan Yin Min Ku Kim Anthony Banks Ungyu Paik Yonggang Huang John A. Rogers 《Advanced functional materials》2015,25(9):1338-1343
Electronics that are capable of destroying themselves, on demand and in a harmless way, might provide the ultimate form of data security. This paper presents materials and device architectures for triggered destruction of conventional microelectronic systems by means of microfluidic chemical etching of the constituent materials, including silicon, silicon dioxide, and metals (e.g., aluminum). Demonstrations in an array of home‐built metal‐oxide‐semiconductor field‐effect transistors that exploit ultrathin sheets of monocrystalline silicon and in radio‐frequency identification devices illustrate the utility of the approaches. 相似文献
998.
High‐Performance Transition Metal Dichalcogenide Photodetectors Enhanced by Self‐Assembled Monolayer Doping 下载免费PDF全文
Dong‐Ho Kang Myung‐Soo Kim Jaewoo Shim Jeaho Jeon Hyung‐Youl Park Woo‐Shik Jung Hyun‐Yong Yu Chang‐Hyun Pang Sungjoo Lee Jin‐Hong Park 《Advanced functional materials》2015,25(27):4219-4227
Most doping research into transition metal dichalcogenides (TMDs) has been mainly focused on the improvement of electronic device performance. Here, the effect of self‐assembled monolayer (SAM)‐based doping on the performance of WSe2‐ and MoS2‐based transistors and photodetectors is investigated. The achieved doping concentrations are ≈1.4 × 1011 for octadecyltrichlorosilane (OTS) p‐doping and ≈1011 for aminopropyltriethoxysilane (APTES) n‐doping (nondegenerate). Using this SAM doping technique, the field‐effect mobility is increased from 32.58 to 168.9 cm2 V?1 s in OTS/WSe2 transistors and from 28.75 to 142.2 cm2 V?1 s in APTES/MoS2 transistors. For the photodetectors, the responsivity is improved by a factor of ≈28.2 (from 517.2 to 1.45 × 104 A W?1) in the OTS/WSe2 devices and by a factor of ≈26.4 (from 219 to 5.75 × 103 A W?1) in the APTES/MoS2 devices. The enhanced photoresponsivity values are much higher than that of the previously reported TMD photodetectors. The detectivity enhancement is ≈26.6‐fold in the OTS/WSe2 devices and ≈24.5‐fold in the APTES/MoS2 devices and is caused by the increased photocurrent and maintained dark current after doping. The optoelectronic performance is also investigated with different optical powers and the air‐exposure times. This doping study performed on TMD devices will play a significant role for optimizing the performance of future TMD‐based electronic/optoelectronic applications. 相似文献
999.
基于大口径闪烁法和差分到达角起伏法开展了间距为3.95 km近水平路径的大气相干长度测量实验。测量结果表明:在同路径的上下行光传播方向上,闪烁法测量相干长度的相关系数为0.94,而到达角起伏法测量相干长度的相关系数为0.79。路径权重的理论分析揭示了闪烁法对路径中部的湍涡敏感,且路径权重函数关于路径中部呈对称分布;到达角起伏法对接收端附近的湍涡敏感,其路径权重函数从发射端到接收端呈单调递增趋势。因此,实际的长距离光传输实验中,在不能确定路径中湍流强度分布的情况下,采用闪烁法测量路径上的湍流效应更适宜。 相似文献
1000.
DaeWha Kang 《Architectural Design》2015,85(4):122-127
How might architectural thinking and processes shift over the next 35 years? How might the architect's role be redefined with shifting ethical values? Could the architect be viewed as less of a design professional and more of a curator engaged in the development of healthy holistic environments, catering for all of society's needs? DaeWha Kang , an architect from 2050, writes to his earlier self, critiquing the work that he undertook in independent practice and as a design director at Zaha Hadid Architects in the mid-2010s. He describes how his design methodologies have evolved in the intervening years. 相似文献