排序方式： 共有45条查询结果，搜索用时 15 毫秒
1.
2.
Kaitlin M. Bratlie Yimin Li Ragnar Larsson Gabor A. Somorjai 《Catalysis Letters》2008,121(3-4):173-178
Kinetic measurements at low temperatures (310–360 K) using gas chromatography (GC) for benzene hydrogenation on Pt(100) and
Pt(111) single crystal surfaces have been carried out at Torr pressures. These kinetic measurements demonstrated a linear
compensation effect for the production of cyclohexane. A detailed application of the model of selective energy transfer to
the experimentally obtained results yields the vibrational frequency of the adsorbate leading to reaction. This frequency
is attributed to ring distortion modes. The vibrational frequency of the heat bath, or catalyst, is ascribed to a Pt-H mode.
An approximate heat of adsorption of the reacting molecule is also calculated from the model. 相似文献
3.
Cameron H. Feriante Samik Jhulki Austin M. Evans Raghunath R. Dasari Kaitlin Slicker William R. Dichtel Seth R. Marder 《Advanced materials (Deerfield Beach, Fla.)》2020,32(2):1905776
Imine-linked 2D covalent organic frameworks (COFs) form more rapidly than previously reported under Brønsted acid-catalyzed conditions, showing signs of crystallinity within a few minutes, and maximum crystallinity within hours. These observations contrast with the multiday reaction times typically employed under these conditions. In addition, vacuum activation, which is often used to isolate COF materials significantly erodes the crystallinity and surface area of the several isolated materials, as measured by N2 sorption and X-ray diffraction. This loss of material quality during isolation for many networks has historically obscured otherwise effective polymerization conditions. The influence of the activation procedure is characterized in detail for three COFs, with the commonly used 1,3,5-tris(4-aminophenyl)benzene-terephthaldehyde network (TAPB-PDA COF), the most prone to pore collapse. When the networks are activated carefully, rapid COF formation is general for all five of the imine-linked 2D COFs studied, with all exhibiting excellent crystallinity and surface areas, including the highest surface areas reported to date for three materials. Furthermore, to simplify the workup of COF materials, a simple nitrogen flow method provides high-quality materials without the need for specialized equipment. These insights have important implications for studying and understanding how 2D COFs form. 相似文献
4.
Kaitlin Wagner Chantal Paquet Yadienka Martinez-Rubi Marc Genest Jingwen Guan Kathleen L. Sampson Keun Su Kim Arnold J. Kell Patrick R. L. Malenfant Benoît H. Lessard 《Advanced Electronic Materials》2021,7(5):2001035
Printed electronics provide inexpensive and light weight electrical components to fuel emerging applications. One major challenge is the high temperature required to sinter conductive metal inks, which leads to thermal degradation of the substrate and subsequently poor performance. A boron nitride nanotube (BNNT) interfacial film is reported for thermal management in rapid processing of a printable silver molecular ink platform using intense pulsed light (IPL) sintering techniques. The inclusion of BNNT thin films of varying surface concentrations deposited between the substrate and the printed features reduces thermal damage to the substrate during sintering while simultaneously improving electrical performance, achieving a sheet resistance value as low as 140 mΩ sq−1. A wide range of sintering energies ranging from 2.0 and 3.2 J cm−2 are investigated along with printed trace widths ranging from 5 mil (0.127 mm) to 20 mil (0.508 mm). Increases in the rate of cooling and in the current carrying capacity are confirmed with the inclusion of the BNNTs. Overall the thin coating of BNNTs presents no drawbacks while significantly improving the electrical properties of IPL sintered conductive traces and thus represents a simple approach that will advance the adoption of IPL for fabricating printed electronic components. 相似文献
5.
Kaitlin A. Doucette Prangthong Chaiyasit Donn L. Calkins Kayli N. Martinez Cameron Van Cleave Callan A. Knebel Anan Tongraar Debbie C. Crans 《International journal of molecular sciences》2021,22(1)
The interactions of amino acids and peptides at model membrane interfaces have considerable implications for biological functions, with the ability to act as chemical messengers, hormones, neurotransmitters, and even as antibiotics and anticancer agents. In this study, glycine and the short glycine peptides diglycine, triglycine, and tetraglycine are studied with regards to their interactions at the model membrane interface of Aerosol-OT (AOT) reverse micelles via 1H NMR spectroscopy, dynamic light scattering (DLS), and Langmuir trough measurements. It was found that with the exception of monomeric glycine, the peptides prefer to associate between the interface and bulk water pool of the reverse micelle. Monomeric glycine, however, resides with the N-terminus in the ordered interstitial water (stern layer) and the C-terminus located in the bulk water pool of the reverse micelle. 相似文献
6.
Conducting nanofibers of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)/polyvinyl alcohol (PEDOT:PSS/PVA) were fabricated at room temperature and via electrospinning with diameters ranging from 100 to 300 nm. The nanofibers were irradiated with Gamma and X-rays for varying lengths of time and the change in conductivity was evaluated. Raman and Electron Spin Resonance spectroscopy of X-ray irradiated nanofibers were obtained to determine the mechanism of conductivity degradation. A decrease in molecular ordering as well as chain scission via chain cross-linking and free radical formation are the two most likely mechanisms for change in conductivity. These nanofibers are promising candidates for use in highly sensitive, real-time electrically based sensor for radiation detection. 相似文献
7.
Alicia Rossi;Ashley Hilmas;Amber Josken;Matthew Dickerson;Kaitlin Detwiler; 《International Journal of Applied Ceramic Technology》2024,21(6):3735-3770
Careful material selection is paramount to meet the significant challenges posed by harsh environments in advanced applications. Ceramic matrix composites (CMCs) have come to the forefront of consideration for many of these applications where environmental resistance needs to be combined with structural stability at high temperatures (1200°C+). Many gaps exist in understanding how material variations pose unique material and design challenges that affect the final performance in a particular application. Thorough materials testing at relevant temperatures is required for various candidate materials to realize an analytical approach to materials selection. This review will discuss mechanical and environmental tests and their use at high temperatures including tensile tests, flexure tests, lifetime testing methods, interlaminar tests, and environmentally relevant tests. Challenges for performing these tests at high temperatures and on CMCs will be discussed. A literature review will provide examples of state-of-the-art testing, and the test results from historical work and improvement opportunities will be addressed. This review aims to provide an overview of the current capabilities and practices for high-temperature testing and recommend best practices for performing high-temperature tests and interpreting and sharing the results and metadata with the larger community to expand the CMC material property database. 相似文献
8.
9.
Boehm Stephen L. II; Schafer Gwen L.; Phillips Tamara J.; Browman Kaitlin E.; Crabbe John C. 《Canadian Metallurgical Quarterly》2000,114(2):401
Neuromuscular impairment by ethanol likely involves complex effects on balance, gait, muscle strength, and other features of motor coordination. The present experiments showed that relative sensitivity to ethanol-induced motor impairment in serotonin 1B (5-HT1B) null mutant and control mice was task dependent. We found that ethanol-treated null mutant mice made fewer missteps on a balance beam than did ethanol-treated wild-type mice, and confirmed a previous finding of their lesser ethanol sensitivity in the grid test. The genotypes did not differ in ethanol sensitivity as measured by the screen test, static dowel, fixed-speed rotarod, accelerating rotarod, grip strength, or loss of righting reflex tests. These experiments suggest that within a behavioral domain, alternative tests of function are not equivalent, so multiple assessment tools should be used to avoid misinterpretation of gene function. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
10.
Yangyang Wang Charlotte Thomas Kaitlin Garman Hwangsun Kim Zonghai Chen Miaofang Chi Chunmei Ban 《Advanced functional materials》2024,34(45):2404434
Solid electrolytes (SEs) have the potential to enhance the safety and performance of Li-metal batteries. However, the existence of grain boundaries in polycrystalline SEs presents a significant challenge for both ionic and electronic migration, promoting the propagation of detrimental lithium dendrites. This study compares the roles of grain boundaries in electrical properties of three distinct SEs including garnet-type Li6.5La3Zr1.5Ta0.5O12 (LLZO), argyrodite-type Li6PS5Cl (LPSC), and NASICON-type Li1+x+yAlx(Ti,Ge)2-xSiyP3-yO12 (LATP). Results demonstrate that the electronic and ionic conductivities of solid-state electrolytes are affected differently by grain boundaries, depending on the specific type of electrolyte. For instance, LLZO and LATP experience dielectric breakdown at 3.7 and 5.3 V, respectively, while LPSC does not exhibit such behavior. Here, a new chemical modification is proposed that simultaneously alters the composition of both the surface and grain boundaries of SEs, ultimately reducing electronic conductivity for the LLZO SEs. Consequently, the proposed LLZO exhibits unprecedented dendrite-free cycling stability, achieving a remarkable 12 000-h lifetime at room temperature, surpassing conventional strategies such as surface coatings in dendrite mitigation. This study highlights the significance of modifying grain boundaries to design safe and durable Li-metal batteries. It provides new insights for developing SEs that are highly resistant to dendrite formation. 相似文献