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11.
Fujiwara M Akimune H van Den Berg AM Cribier M Daito I Ejiri H Fujimura H Fujita Y Goodman CD Hara K Harakeh MN Ihara F Ishikawa T Janecke J Kawabata T Raghavan RS Schwarz K Tanaka M Yamanaka T Yosoi M Zegers RG 《Physical review letters》2000,85(21):4442-4445
Discrete Gamow-Teller (GT) transitions 176Yb-->176Lu at low excitation energies have been measured via the ( 3He,t) reaction at 450 MeV and at 0 degrees. For 176Yb, two low-lying states are observed, setting low thresholds Q(nu) = 301 and 445 keV for neutrino ( nu) capture. Capture rates estimated from the measured GT strengths, the simple two-state excitation structure, and the low Q(nu) in Yb-Lu indicate that Yb-based nu detectors are well suited for a direct measurement of the sub-MeV solar electron-neutrino ( nu(e)) spectrum including pp neutrinos. 相似文献
12.
The energy-transducing N,N'-dicyclohexylcarbodiimide-sensitive (DCCD-sensitive) ATPase complex consists of two parts, a soluble catalytic protein (F1), and an intrinsic membrane protein (F0). The bacterial coupling factor complex, BCF0-BCF1, has recently been purified from Mycobacterium phlei, and used to reconstitute oxidative phosphorylation in detergent-extracted membranes. The BCF0 moiety has been purified by being recovered from the purified BCF0-BCF1 complex by affinity chromatography. BCF0 is a lipoprotein or lipoprotein complex with an approximate molecular weight of 60,000. The preparation contained 0.15 mg of phospholipid per milligram protein. There appear to be three polypeptides, with approximate molecular weights of 24,000, 18,000, and 8,000 as determined by sodium dodecylsulfate acrylamide gel electrophoresis. Purified BCF0 conferred DCCD sensitivity on a purified BCF1 preparation. Reconstitution of oxidative phosphorylation was achieved after incubation of detergent-extracted membranes with purified BCF0 and purified BCF1. 相似文献
13.
Self-injection length in La0.7Ca0.3MnO3-YBa2Cu3O7-δ ferromagnet-superconductor multilayer thin films
We have carried out extensive studies on the self-injection problem in barrierless heterojunctions between La0.7Ca0.3MnO3 (LCMO) and YBa2Cu3O7-δ (YBCO) thin films. The heterojunctions were formed in situ by sequentially growing LCMO and YBCO films on 〈100〉 LaAlO3 (LAO) substrate using a pulsed laser deposition (PLD) system. YBCO micro-bridges with 64 μm width were patterned both on
the LAO (control) and LCMO side of the substrate. Critical current, I
c, was measured at 77 K on both the control side as well as the LCMO side for different YBCO film thickness. It was observed
that while the control side showed a J
c of ∼ 2 × 106 A/cm2, the LCMO side showed about half the value for the same thickness (1800 ?). The difference in J
c indicates that a certain thickness of YBCO has become ‘effectively’ normal due to self-injection. From the measurement of
J
c at two different thicknesses (1800 ? and 1500 ?) of YBCO films both on the LAO as well as the LCMO side, the value of self-injection
length (at 77 K) was estimated to be ∼ 900 ?. To the authors’ best knowledge, this is the first time that self-injection length
has been quantified. A control experiment carried out with LaNiO3 deposited by PLD on YBCO did not show any evidence of self-injection. 相似文献
14.
Current methods for optimization of stand treatment and forest-wide harvest scheduling use mathematical programming that presumes perfect information on production, costs, and revenues over long planning periods. These approaches simultaneously optimize harvest for all periods in the planning horizon. In contrast, the method presented here assumes that stand-level planning and harvest scheduling proceed sequentially rather than simultaneously over every period. A backward-recursion dynamic program is used to determine the discounted net value of a wide range of current harvest strategies for each stand class in the forest inventory on the basis of a projected set of optimal treatments for future harvest and regeneration of each stand. The most highly valued strategy is selected if there are no volume constraints. Otherwise, suboptimal harvest alternatives are ranked in order of increasing opportunity cost for increasing or decreasing harvest; constraints met only up to a maximum opportunity cost is also demonstrated. 相似文献
15.
Zhan W Jiang Y Sharma S Brodie PJ Bane S Kingston DG Liotta DC Snyder JP 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(52):14792-14804
A series of conformationally restrained epothilone analogues with a short bridge between the methyl groups at C6 and C8 was designed to mimic the binding pose assigned to our recently reported EpoA-microtubule binding model. A versatile synthetic route to these bridged epothilone analogues has been successfully devised and implemented. Biological evaluation of the compounds against A2780 human ovarian cancer and PC3 prostate cancer cell lines suggested that the introduction of a bridge between C6-C8 reduced potency by 25-1000 fold in comparison with natural epothilone D. Tubulin assembly measurements indicate these bridged epothilone analogues to be mildly active, but without significant microtubule stabilization capacity. Molecular mechanics and DFT energy evaluations suggest the mild activity of the bridged epo-analogues may be due to internal conformational strain. 相似文献
16.
Realization of a Framework for Simulation-Based Large-Scale Shape Optimization Using Vertex Morphing
Ghantasala Aditya Najian Asl Reza Geiser Armin Brodie Andrew Papoutsis Efthymios Bletzinger Kai-Uwe 《Journal of Optimization Theory and Applications》2021,189(1):164-189
Journal of Optimization Theory and Applications - There is a significant tendency in the industry for automation of the engineering design process. This requires the capability of analyzing an... 相似文献
17.
AM Jayannavar 《Pramana》2002,58(2):173-181
We present a simple model of transmission across a metallic mesoscopic ring. In one of its arm an electron interacts with
a single magnetic impurity via an exchange coupling. We show that entanglement between electron and spin impurity states leads
to reduction of Aharonov-Bohm oscillations in the transmission coefficient. The spin-conductance is asymmetric in the flux
reversal as opposed to the two-probe electrical conductance which is symmetric. In the same model, in contradiction to the
naive expectation of a current magnification effect, we observe enhancement as well as suppression of this effect depending
on the system parameters. The limitations of this model to the general notion of dephasing or decoherence in quantum systems
are pointed out. 相似文献
18.
Simple high-performance liquid chromatographic method for the measurement of amiloride in body fluids 总被引:1,自引:0,他引:1
G Forrest G T McInnes A P Fairhead G G Thompson M J Brodie 《Journal of chromatography. A》1988,428(1):123-130
A simplified rapid high-performance liquid chromatographic (HPLC) procedure has been developed for the measurement of amiloride in plasma or urine. Solid-phase extraction columns provide quick, clean and simple sample preparation, allowing ten samples to be processed in less than 5 min. The HPLC system uses a standard reversed-phase (C18) column with detection by ultraviolet absorption at 365 nm. The assay has been used to define plasma amiloride concentration-time profiles and to quantitate urine amiloride recovery in healthy men after repeated administration at two doses. 相似文献
19.
R R Brodie L F Chasseaud L M Walmsley A Darragh D A O'Kelly 《Journal of chromatography. A》1979,179(2):301-309
Azanidazole can be measured in plasma and urine by reversed-phase high-performance liquid chromatography employing UV detection. Peak mean plasma concentrations of azanidazole, of 267 ng/ml, occurred at 1.5 h after single oral doses to human subjects, and declined with a half-life of 0.8 h. Less than 0.5% of the dose was excreted in the urine as unchanged drug. Metabolites of azanidazole were also detected by the procedures used. 相似文献
20.
Ainscough EW Brodie AM Chaplin AB O'Connor JM Otter CA 《Dalton transactions (Cambridge, England : 2003)》2006,(10):1264-1266
A new diphosphine ligand assembled on the cyclotriphosphazene platform forms linear chelate and dimetallic bridged complexes with Au(I) and a cis-chelate complex with Pt(II). 相似文献