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51.
Chelsea Weir Michelle L. Pantoya Gautham Ramachandran Tim Dallas Daniel Prentice Michael Daniels 《Journal of Electrostatics》2013,71(1):77-83
Composite energetic material response to electrical stimuli was investigated and a correlation between electrical conductivity and ignition sensitivity was examined. The composites consisted of micrometer particle aluminum combined with another metal, metal oxide, or fluoropolymer. Of the nine tested mixtures, aluminum (Al) with copper oxide (CuO) was the only mixture to ignite by electrostatic discharge. Under the loose powder conditions of these experiments, the Al–CuO minimum ignition energy (MIE) is 25 mJ and exhibited an electrical conductivity two orders of magnitude higher than the next composite. This study showed a similar trend in MIE for ignition triggered by a discharged spark compared with a thermal hot wire source. 相似文献
52.
Rachel A. Hegemann Laura M. Smith Alethea B.T. Barbaro Andrea L. Bertozzi Shannon E. Reid George E. Tita 《Physica A》2011,390(21-22):3894-3914
We propose an agent-based model to simulate the creation of street gang rivalries. The movement dynamics of agents are coupled to an evolving network of gang rivalries, which is determined by previous interactions among agents in the system. Basic gang data, geographic information, and behavioral dynamics suggested by the criminology literature are integrated into the model. The major highways, rivers, and the locations of gangs’ centers of activity influence the agents’ motion. We use a policing division of the Los Angeles Police Department as a case study to test our model. We apply common metrics from graph theory to analyze our model, comparing networks produced by our simulations and an instance of a Geographical Threshold Graph to the existing network from the criminology literature. 相似文献
53.
Lai Hong Wong Asier Unciti-Broceta Michaela Spitzer Rachel White Mike Tyers Lea Harrington 《Chemistry & biology》2013,20(3):333-340
Highlights? Growth arrest induced by human telomerase in yeast is chemically reversible ? Readout is sensitive to telomerase catalytic activity and telomere recruitment ? Three cell-permeable compounds also inhibit purified human telomerase ? Yeast can be successfully used to screen for human telomerase inhibitors 相似文献
54.
Yan Li Dr. Kazuki Fukushima Dr. Daniel J. Coady Dr. Amanda C. Engler Dr. Shaoqiong Liu Yuan Huang Dr. John S. Cho Dr. Yi Guo Dr. Lloyd S. Miller Dr. Jeremy P. K. Tan Dr. Pui Lai Rachel Ee Dr. Weimin Fan Prof. Yi Yan Yang Dr. James L. Hedrick 《Angewandte Chemie (International ed. in English)》2013,52(2):674-678
55.
Lu Cao Dehong Chen Rachel A. Caruso 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2013,125(42):11192-11197
56.
Torsten Kerber Rachel Nathaniel Kerber Xavier Rozanska Philippe Sautet Paul Fleurat‐Lessard 《Journal of computational chemistry》2013,34(13):1155-1163
We present a new software to easily perform QM:MM and QM:QM' calculations called QMX. It follows the subtraction scheme and it is implemented in the Atomic Simulation Environment (ASE). Special attention is paid to couple molecular calculations with periodic boundaries approaches. QMX inherits the flexibility and versatility of the ASE package: any combination of methods namely force field, semiempirical, first principle, and ab initio, can be used as hybrid potential energy surface (PES). Its ease of use is demonstrated by considering the adsorption of Al2Cl3Me3 on silica surface and by combining different levels of theory (from standard DFT to MP2 calculations) for the so‐called High Level cluster with standard PW91 density functional theory calculations for the Low Level environment. It is shown that the High Level cluster must contain the silanol group close to the aluminum atoms. The bridging adsorption is favored by 58 kJ mol?1 at the MP2:PW91 level with respect to the terminal position. Using large clusters at the MP2:PW91 level, it is shown that PW91 calculations are sufficient for structure optimization but that embedded methods are required for accurate energy profiles. © 2013 Wiley Periodicals, Inc. 相似文献
57.
The synthesis is reported of a series of apolar nematic liquid crystals incorporating an alkoxyalkoxy chain attached in a terminal position to the molecular core. The dependence of the mesomorphism and phase transition temperatures on the nature of the terminal chain with one, two or three oxygen atoms was studied. Some compounds with a completely alicyclic molecular core and a terminal 2‐methoxyethoxy chain exhibit a nematic phase with a low melting point, birefringence and viscosity and a relatively high clearing point in the absence of smectic phases. They do not to absorb light in the near UV and may be useful as components of UV‐stable nematic mixtures for use in photoluminescent liquid crystal displays. The presence of the methoxyethoxy chain leads to a relatively large dipole moment perpendicular to the molecular long axis. 相似文献
58.
Mary E. Neubert Corresponding author Michael R. Fisch Sandra S. Keast Julie M. Kim Mark C. Lohman Rachel S. Murray 《Liquid crystals》2013,40(7):941-963
The typical sidewalls produced in the fabrication of protrusion electrodes are proposed to create a low voltage (4.5 Vrms) and high transmittance (93%) blue-phase liquid crystal display (BP-LCD). The tilted electrodes produce a strong horizontal electrical field that reduces the operating voltage considerably. The common problem of the ‘dead zones’ is solved by reflecting the light onto the electrodes. In order to estimate the phase retardation of the reflected light, a ray tracing simulation program for anisotropic mediums has been developed. The proposed device is more competitive than vertical field switching based BP-LCD and also, has the advantages of protruded in-plane-switching structures. These facts make this technology a potential candidate for the next generation of BP-LCDs. 相似文献
59.
Julie M. Herniman Peter R. Worsley Rachel Greenhill Dan L. Bader G. John Langley 《Journal of separation science》2022,45(2):542-550
Liquid chromatography-mass spectrometry methods were required to afford the rapid separation and detection of purines and small organic acids. These compounds are found in sweat and sebum and are potential biomarkers for the early detection of pressures sores. Two ultra-high-performance supercritical fluid chromatography-mass spectrometry assays have been successfully developed for both classes of compounds. Separation for purines was achieved using a gradient of supercritical carbon dioxide and methanol with a 1-aminoanthracene sub 2 μm particle size column followed by positive ion electrospray ionization. Separation for organic acids was achieved using a gradient of supercritical carbon dioxide and methanol (50 mM ammonium acetate 2% water) with a Diol sub 2 μm particle size column followed by negative ion electrospray ionization. Calibration curves were created in the absence of internal standards and R2 values > 0.96 were achieved using single ion monitoring methods for the protonated purines and the deprotonated acids. The two new assays afford rapid analytical methods for the separation and detection of potential biomarkers in human sweat leading to the early detection and prevention of pressure sores. 相似文献
60.
Melissa M. Cadelis Soeren Geese Benedict B. Uy Daniel R. Mulholland Shara J. van de Pas Alex Grey Bevan S. Weir Brent R. Copp Siouxsie Wiles 《Molecules (Basel, Switzerland)》2021,26(4)
Antimicrobial bioassay-guided fractionation of the endophytic fungi Neofusicoccum australe led to the isolation of a new unsymmetrical naphthoquinone dimer, neofusnaphthoquinone B (1), along with four known natural products (2–5). Structure elucidation was conducted by nuclear magnetic resonance (NMR) spectroscopic methods, and the antimicrobial activity of all the natural products was investigated, revealing 1 to be moderately active towards methicillin-resistant Staphylococcus aureus (MRSA) with a minimum inhibitory concentration (MIC) of 16 µg/mL. 相似文献