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991.
Europium tetrakis dibenzoylmethide triethylammonium crystals are highly triboluminescent, indicating possible use in structural health monitoring. This work investigates the effect of synthesis conditions on crystalline yield and morphology of this material. Less solvent yields more material, but may cause striations in crystal faces. No statistical effect on triboluminescent yield was recorded. Scanning electron microscopy shows crystal size varies from 30–400 μm based on synthesis conditions. 相似文献
992.
Dr. Philipp Beck Theresa A. Lansdell Nicole M. Hewlett Prof. Dr. Jetze J. Tepe Prof. Dr. Michael Groll 《Angewandte Chemie (International ed. in English)》2015,54(9):2830-2833
The proteasome represents an invaluable target for the treatment of cancer and autoimmune disorders. The application of proteasome inhibitors, however, remains limited to blood cancers because their reactive headgroups and peptidic scaffolds convey unfavorable pharmacodynamic properties. Thus, the discovery of more drug‐like lead structures is indispensable. In this study, we present the first structure of the proteasome in complex with an indolo‐phakellin that exhibits a unique noncovalent binding mode unparalleled by all hitherto reported inhibitors. The natural product inspired pentacyclic alkaloid binds solely and specificially into the spacious S3 subpocket of the proteasomal β5 substrate binding channel, gaining major stabilization through halogen bonding with the protein backbone. The presented compound provides an ideal scaffold for the structure‐based design of subunit‐specific nonpeptidic proteasome‐blockers. 相似文献
993.
Bolling Stacey D. Reynolds Jacob G. Ely Thomas M. Lachut James S. Lamothe Margaret E. Cooke Gary A. 《Journal of Radioanalytical and Nuclear Chemistry》2020,323(1):329-339
Journal of Radioanalytical and Nuclear Chemistry - The Hanford Site, near Richland, Washington in the U.S.A., is implementing a treatment process for liquid radioactive waste. This study determined... 相似文献
994.
Zhaolu Diao Christopher Bonzon Giacomo Scalari Mattias Beck Jrme Faist Romuald Houdr 《Laser \u0026amp; Photonics Reviews》2013,7(5):L45-L50
Compact semiconductor light sources with high performance continuous‐wave (CW) and single mode operation are highly demanded for many applications in the terahertz (THz) frequency range. Distributed feedback (DFB) and photonic crystal (PhC) quantum cascade (QC) lasers are amongst the leading candidates in this field. Absorbing boundary condition is a commonly used method to control the optical performance of a laser in double‐metal confinement. However, this approach increases the total loss in the device and results in a large threshold current density, limiting the CW maximum output power and operating temperature. In this letter, a robust surface emitting continuous‐wave terahertz QC laser is realized in a two‐dimensional PhC structure by a second order Bragg grating extractor that simultaneously provides the boundary condition necessary for mode selection. This results in a 3.12 THz single mode CW operation with a 3 mW output power and a maximum operation temperature (Tmax) of 100 K. Also, a highly collimated far‐field pattern is demonstrated, which is an important step towards real world applications. 相似文献
995.
Yeping Yuan Margaret E. Avener Alexander R. Horner-Devine 《Experiments in fluids》2011,50(5):1235-1245
We describe a technique for measuring the layer thickness of two interacting buoyant rotating gravity currents. The technique
can be used generally to differentiate between water masses in experiments with multiple sources and is used here to simulate
the dynamics of two adjacent coastal river plumes. The plumes are generated using two identical fresh water inlets, with blue
and red dye indicating upstream and downstream river flows, respectively. Two parameters, normalized intensity and color ratio,
are measured with a 3-CCD color video camera and used to develop a two-dimensional (intensity–color ratio) calibration map
for layer thickness. The calibration is used successfully to determine the depth field for the combined two-plume system and
to differentiate between the two plumes. This technique is applied to compute the volumetric growth of a large eddy near the
freshwater source and the transport rate of buoyant fluid away from the source in the coastal current. The validation tests
show good agreement between the calculated plume volume and the input fresh water volume. 相似文献
996.
Algebra of Efficient Sets for Multiobjective Complex Systems 总被引:1,自引:0,他引:1
Melissa Gardenghi Trinidad Gómez Francisca Miguel Margaret M. Wiecek 《Journal of Optimization Theory and Applications》2011,149(2):385-410
Complex systems are modeled as collections of multiobjective programs representing interacting subsystems of the overall system.
Since the calculation of efficient sets of these complex systems is challenging, it is desirable to decompose the overall
system into component multiobjective programs, that are more easily solved and then construct the efficient set of the overall
system. For some classes of complex systems, algebraic properties of set operations and relations are developed between the
efficient set of the overall system and the efficient sets of subproblems. The properties indicate that multiple decomposition
and coordination schemes, with varying assumptions regarding the system, may be applied to the same initial system. 相似文献
997.
Click phosphorylation of a propargylated unprotected peptide and phosphoryl azide using chaotrope-assisted Cu(I)-catalyzed 1,3-dipolar cycloaddition enabled a high-yielding and rapid synthesis of a nucleoside diphosphate kinase (NDPK) phosphocarrier domain. The synthesis showcases a valuable synthetic platform for the synthesis of biologically relevant phosphopeptide analogues. 相似文献
998.
He S Li H Yip YW Yeung CT Fung YO Kong HK Yeung HL Law GL Wong KL Lee CS Lam MH Murphy MB Lam PK Wong WT 《Organic letters》2011,13(19):5036-5039
A water-soluble europium(III) complex (1) has been synthesized and demonstrated to be a specific fluorescence probe for the paralytic shellfish toxin saxitoxin, a neurotoxin that blocks the voltage-gated sodium channels on cell membranes. Saxitoxin binds to the europium complex (K(B) = 6.1 × 10(4) M(-1)) and triggers a two-photon induced f-f emission enhancement by over 100% and increases the two-photon absorption cross-section from 9 to 36 GM. 相似文献
999.
Margaret E.M. Thomas 《Annals of Pure and Applied Logic》2011,162(6):409
We prove, by explicit construction, that not all sets definable in polynomially bounded o-minimal structures have mild parameterization. Our methods do not depend on the bounds particular to the definition of mildness and therefore our construction is also valid for a generalized form of parameterization, which we call G-mild. Moreover, we present a cell decomposition result for certain o-minimal structures which may be of independent interest. This allows us to show how our construction can produce polynomially bounded, model complete expansions of the real ordered field which, in addition to lacking G-mild parameterization, nonetheless still have analytic cell decomposition. 相似文献
1000.
D. Hofstetter J. Di Francesco L. Hvozdara H.-P. Herzig M. Beck 《Applied physics. B, Lasers and optics》2011,103(4):967-970
We report a prototype CO2 gas sensor based on a simple blackbody infrared source and a spectrally narrow quantum cascade detector (QCD). The detector
absorption spectrum is centered at 2260 cm−1 (4.4 μm) and has a full width at half maximum of 200 cm−1 (25 meV). It covers strong absorption bands of two spectrally overlapping CO2 isotopomers, namely the P-branch of 12CO2 and the R-branch of 13CO2. Acquisition of the spectral information and data treatment were performed in a Fourier transform infrared (FTIR) spectrometer.
By flushing its sample compartment either with nitrogen, dry fresh air, ambient air, or human breath, we were able to determine
CO2 concentrations corresponding to the different gas mixtures. A detection limit of 500 ppb was obtained in these experiments. 相似文献