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Beerlink A Wilbrandt PJ Ziegler E Carbone D Metzger TH Salditt T 《Langmuir : the ACS journal of surfaces and colloids》2008,24(9):4952-4958
Silicon and Teflon substrates have been structured by wet etching and a focused ion beam (FIB) to obtain very defined, clean apertures. Planar, free-standing lipid membranes (black lipid membranes (BLM)) with enhanced long-term stability have been prepared on these apertures by the methods of Montal and Müller(1,2) as well as Müller and Rudin.(3) The stability and geometric control enables the use of X-ray analysis of free-standing single bilayers. With the presented setup, simultaneous structural and electrophysiological measurements will become feasible. 相似文献
3.
Abe Y Aberle C Akiri T dos Anjos JC Ardellier F Barbosa AF Baxter A Bergevin M Bernstein A Bezerra TJ Bezrukhov L Blucher E Bongrand M Bowden NS Buck C Busenitz J Cabrera A Caden E Camilleri L Carr R Cerrada M Chang PJ Chimenti P Classen T Collin AP Conover E Conrad JM Cormon S Crespo-Anadón JI Cribier M Crum K Cucoanes A D'Agostino MV Damon E Dawson JV Dazeley S Dierckxsens M Dietrich D Djurcic Z Dracos M Durand V Efremenko Y Elnimr M Endo Y Etenko A Falk E Fallot M Fechner M von Feilitzsch F 《Physical review letters》2012,108(13):131801
The Double Chooz experiment presents an indication of reactor electron antineutrino disappearance consistent with neutrino oscillations. An observed-to-predicted ratio of events of 0.944±0.016(stat)±0.040(syst) was obtained in 101 days of running at the Chooz nuclear power plant in France, with two 4.25 GW(th) reactors. The results were obtained from a single 10 m(3) fiducial volume detector located 1050 m from the two reactor cores. The reactor antineutrino flux prediction used the Bugey4 flux measurement after correction for differences in core composition. The deficit can be interpreted as an indication of a nonzero value of the still unmeasured neutrino mixing parameter sin(2)2θ(13). Analyzing both the rate of the prompt positrons and their energy spectrum, we find sin(2)2θ(13)=0.086±0.041(stat)±0.030(syst), or, at 90% C.L., 0.017相似文献
4.
Zaharko O Daoud-Aladine A Streule S Mesot J Brown PJ Berger H 《Physical review letters》2004,93(21):217206
We present the results of the first neutron powder and single crystal diffraction studies of the coupled spin tetrahedra systems Cu2Te2O5X2 (X = Cl,Br). Incommensurate antiferromagnetic order with the propagation vectors kCl approximately [0.150,0.422,1/2], kBr approximately [0.158,0.354,1/2] sets in below TN = 18 K for X = Cl and 11 K for X = Br. No simple collinear antiferromagnetic or ferromagnetic spin arrangements within Cu2+ tetrahedra fit these observations. Fitting the diffraction data to more complex but physically reasonable models with multiple helices leads to a moment of 0.67(1)microB/Cu2+ at 1.5 K for the Cl compound. The reason for such a complex ground state may be geometrical frustration of the spins due to the intratetrahedral and intertetrahedral couplings having similar strengths. In neither compound has any evidence for a structural transition accompanying the magnetic ordering been found. 相似文献
5.
M. Wolff C. Krüger P. Homenya L. Heyer R. Saadat B. Dreyer D. Unruh T. Meyer G. Klingelhoefer L. Rissing R. Sindelar Y. Ichiyanagi F. Renz 《Hyperfine Interactions》2014,226(1-3):237-241
Mononuclear iron complexes in which the iron(III) ion is coordinated by a pentadentate Schiff base ligand L5 with two phenolate, two imino and one amino group can exhibit a spin crossover. In this contribution experimental results are presented for complexes with cyanate and thiocyanate as co-ligands. Furthermore, theoretical results of quantum chemical calculations of energies and entropies for the low-spin and high-spin state are shown and compared with Mössbauer results. We also demonstrate how the ligand field of the monodentate co-ligand influences the spin crossover energies and entropies in [FeIIIL5NCY] complexes. 相似文献
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Besides a structural isomerization to the title compound undergoes a faster automerization as shown by D-labelling; the change in the ratio of rearrangements of to ring contracted points to conformational effects in the reorganizations of . 相似文献
7.
The total synthesis of (+/-)-2- O-methylneovibsanin H was achieved in 12 steps. An acid-catalyzed, one-pot, four-step cascade reaction was key to the concise total synthesis, lending support to the proposed biosynthesis. 相似文献
8.
Perevedentseva E Cai PJ Chiu YC Cheng CL 《Langmuir : the ACS journal of surfaces and colloids》2011,27(3):1085-1091
Recently, nanodiamond particles have attracted increasing attention as a promising nanomaterial for its biocompatibility, easy functionalization and conjugation with biomolecules, and its superb physical/chemical properties. Nanodiamonds are mainly used as markers for cell imaging, using its fluorescence or Raman signals for detection, and as carriers for drug delivery. For the success of these applications, the biomolecule associated with the nanodiamond has to retain its functionality. In this work, the protein activities of egg white lysozyme adsorbed on nanodiamond particles of different sizes is investigated. The lysozyme nanodiamond complex is used here as a protein model for analyzing its structural conformation changes and, correspondingly, its enzymatic activity after the adsorption. Fourier-transform infrared spectroscopy (FTIR) is used for the analysis of the sensitive protein secondary structure. To access the activities of the adsorbed lysozyme, a fluorescence-based assay is used. The process of adsorption is also analyzed using UV-visible spectroscopic measurements in combination with analysis of nanodiamond properties with FTIR, Raman spectroscopy, and ζ-potential measurements. It is found that the activity of lysozyme upon adsorption depends on the nanodiamond's size and surface properties, and that the nanodiamond particles can be selected and treated, which do not alter the lysozyme functional properties. Such nanodiamonds can be considered convenient nanoparticles for various bioapplications. 相似文献
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A. Nikiel T. Palasz M. Suchanek M. Abboud A. Sinatra Z. Olejniczak T. Dohnalik G. Tastevin P-J. Nacher 《The European physical journal. Special topics》2007,144(1):255-263
Systematic studies of the metastability exchange optical
pumping (MEOP) process in 3He gas at high magnetic fields (0.45, 0.9, 1.5,
and 2 T) and pressures (32 and 64 mbar) are performed. The impact of
experimental parameters such as laser power, beam profile, and shape
of the pumping cell is evaluated. By varying the discharge intensity
in the cell, the density of metastable state atoms and the plasma-induced
nuclear relaxation rate are also controlled, and their effect
on the MEOP efficiency can be investigated. Very accurate experimental
results are obtained, opening the way to quantitative tests of a
recently proposed model of the MEOP process at high magnetic field.
We report selected MEOP results with nuclear polarizations exceeding
50 % at 64 mbar and 2 T, which represents a dramatic improvement in
performances over MEOP at low magnetic field. The present findings
suggest that still higher polarizations can be achieved in higher
magnetic fields, and motivate investigations at higher gas pressures.
New ways of producing hyperpolarized 3He for magnetic resonance imaging
and medical applications can be envisaged, as most clinical whole-body
scanners operate at 1.5 T. 相似文献
10.
Thomas B. Buxton Brian Catto Jack Horner Rex Yannis J. Peter Rissing 《Microchemical Journal》1986,34(3)
Phospholipase A2 and C activity was quantitated using liposomes impregnated with alkaline phosphatase. Release of alkaline phosphatase was dependent on phospholipase related hydrolysis of intact vesicles. Released alkaline phosphatase was quantitated after addition of its chromogenic substrate p-nitrophenyl phosphate. The lower limit of detectability for phospholipase A2 and C activity was 0.5 unit/ml. These limits were 10-fold lower than a titrimetric method. Liposome destruction as measured by alkaline phosphatase release was calcium dependent and inhibited by 1 mM EDTA and 1 mM ZnSO4. The assay was technically simple, generated same day results, and used automated enzyme-linked immunosorbent assay instrumentation. 相似文献