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991.
Elizabeth A. Carter Matthew A. Pasek Tim Smith Terence P. Kee Peter Hines Howell G. M. Edwards 《Analytical and bioanalytical chemistry》2010,397(7):2647-2658
A fulgurite is a naturally occurring glass formed when lightning hits sand, rock, or soil. The formation of fulgurites is
accompanied by mineralogical and sometimes compositional changes, and may record information about the environment in which
they were formed. A previous investigation using Raman point spectroscopy discovered the presence of anatase, a low-temperature
polymorph of TiO2, and polyaromatic hydrocarbons within a fulgurite. These findings indicate that there were regions within the sample that
were not subjected to temperatures of 2,000 K or more that the matrix is reported to attain when struck by lightning. This
paper seeks to expand the previous research by utilizing the capabilities of a new Raman spectroscopic technological development
that enables rapid mapping. The entire surface area of a cross-sectioned fulgurite (∼40 mm × 23 mm) sample was mapped allowing
several regions of polyaromatic hydrocarbons and anatase to be located. Furthermore, shocked quartz was found within the boundary
regions of the fulgurite, and is proposed to have resulted from contact with vaporized material during the lightning strike.
Shocked quartz is typically indicative of extraterrestrial impact, yet its discovery here suggests that its formation is not
exclusive to the impact process. 相似文献
992.
993.
994.
Prof. Dr. Sunney I. Chan Yu‐Jhang Lu Dr. Penumaka Nagababu Dr. Suman Maji Mu‐Cheng Hung Marianne M. Lee Prof. Dr. I‐Jui Hsu Pham Dinh Minh Jeff C.‐H. Lai Kok Yoah Ng Sridevi Ramalingam Prof. Dr. Steve S.‐F. Yu Prof. Dr. Michael K. Chan 《Angewandte Chemie (International ed. in English)》2013,52(13):3731-3735
995.
Dipl.-Phys. Lena Scherthan Rouven F. Pfleger Dr. Hendrik Auerbach Dipl.-Phys. Tim Hochdörffer Dr. Juliusz A. Wolny Dr. Wenli Bi Dr. Jiyong Zhao Dr. Michael Y. Hu Dr. E. Ercan Alp Dr. Christopher E. Anson Prof. Rolf Diller Prof. Annie K. Powell Prof. Volker Schünemann 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(23):8902-8907
996.
997.
Dr. Khrystyna Herasymchuk Magali Allain Gregory A. MacNeil Dr. Vincent Carré Prof. Frédéric Aubriet Prof. Daniel B. Leznoff Prof. Marc Sallé Dr. Sébastien Goeb Prof. Tim Storr 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(65):16161-16172
The incorporation of a redox-active nickel salen complex into supramolecular structures was explored via coordination-driven self-assembly with homobimetallic ruthenium complexes (bridged by oxalato or 5,8-dihydroxy-1,4-naphthoquinato ligands). The self-assembly resulted in the formation of a discrete rectangle using the oxalato complex and either a rectangle or a catenane employing the larger naphthoquinonato complex. The formation of the interlocked self-assembly was determined to be solvent and concentration dependent. The electronic structure and stability of the oxidized metallacycles was probed using electrochemical experiments, UV-Vis-NIR absorption, EPR spectroscopy and DFT calculations, confirming ligand radical formation. Exciton coupling of the intense near-infrared (NIR) ligand radical intervalence charge transfer (IVCT) bands provided further confirmation of the geometric and electronic structures in solution. 相似文献
998.
999.
Meng-Yu TsaiChin-Chi Hsu Ping-Hei Chen Chao-Sung LinAlexander Chen 《Applied Surface Science》2011,257(20):8640-8646
This study fabricated the large area and optically transparent superhydrophobic silica based films on glass surface with optimized hardness. A silane coupling agent, tetraethoxysilane (TEOS), effectively bonds silica particles onto the glass substrate. Desired surface roughness was obtained by adjusting nano silica particles concentration of the precursors prepared by the sol-gel process. Silica suspension was coated onto the glass substrate by the air brushing methods. This method can deposit a uniform, transparent coating on the glass substrate efficiently. Diluting the precursor by adding ethanol or a mixture of D.I. water and ethanol further improved the transmittance and superhydrophobicity efficiency. The results showed that as the silica particle concentration and the thickness of the coating were increased, the surface roughness was enhanced. Rougher surface displayed a higher superhydrophobicity and lower transmittance. Therefore, the concentration of silica particle, volume of coatings, and the ratio of ethanol and D.I. water are of great importance to deposit a transparent, superhydrophobic coating on glass. 相似文献
1000.
We have developed an oscillatory cross-slot extensional rheometer capable of performing measurements with unprecedentedly small volumes of test fluids (??10?C100???L). This provides the possibility of studying exotic and precious or scarce bio-fluids, such as synovial fluid. To test our system, we have looked at a relatively abundant and accessible biological fluid, namely human saliva; a complex aqueous mixture of high molecular weight mucin molecules and other components. The results represent our first attempts to by this technique and as yet we have only sampled a small dataset. However, we believe we have produced the first successful quantitative measurements of extensional viscosity, Trouton ratio, and flow-induced birefringence made on saliva samples. The results significantly add to the scant literature on saliva rheology, especially in extension, and demonstrate the important role of saliva extensibility in relation to function. 相似文献