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1.
Stephan?HaiberEmail author Xingtao?Ai Henning?Bubert Moritz?Heintze Volker?Brüser Waltraut?Brandl Gabriela?Marginean 《Analytical and bioanalytical chemistry》2003,375(7):875-883
Plasma chemically modified carbon nanofibers were characterized by X-ray photoelectron spectroscopy with regard to the content of carbon, oxygen, and nitrogen and the contribution of carboxylic groups or ester, carbonyl and hydroxylic groups or ether on the surface. Unfortunately, X-ray photoelectron spectroscopy only provides an average value of the first 10 to 15 molecular layers. For comparison, depth profiles were measured and wet chemical methods were applied to estimate the thickness of the functionalized layer and the distribution of oxygen-containing functional groups within the near-surface layers. The results indicate that the fiber surface is covered by a monomolecular oxygen-containing layer and that plasma treatment allows a complete oxygen functionalization of the uppermost surface layer. The best conditions for plasma treatment found within the set of parameters applied to generate complete functionalization are: plasma gas O(2)/Ar ratio 1:1, gas pressure 1-1.5 hPa, plasma power 80 W, treatment time >or= 5 min. Additionally, three quick and easy methods are presented to estimate the efficiency of plasma treatment with regard to surface functionalization: pyrolysis, contact angle measurements, and light permeability measurements of aqueous carbon nanofiber suspensions. 相似文献
2.
S. Torilov S. Thummerer W. von Oertzen Tz Kokalova G. de Angelis H. G. Bohlen A. Tumino M. Axiotis E. Farnea N. Marginean T. Martinez D. R. Napoli M. De Poli S. M. Lenzi C. Ur M. Rousseau P. Papka 《The European Physical Journal A - Hadrons and Nuclei》2004,19(3):307-317
We have studied the reactions
as well as the binary channel
, in order to search for deformed states, which form rotational bands in 40Ca. We observe positive- and negative-parity bands. The negative-parity band is proposed to be a partner of an inversion doublet with the positive-parity states being based on 4p-4h configurations. The properties of the positive-parity states are discussed on the basis of the shell model and the parity doublet on the basis of a cluster model with intrinsic reflection asymmetric shapes.Received: 2 May 2003, Revised: 23 September 2003, Published online: 20 January 2004PACS:
21.10.-k Properties of nuclei; nuclear energy levels - 21.60.Gx Cluster models 相似文献
3.
P. Mason N. Marginean G. Montagnoli S. Beghini F. Scarlassara E. Farnea C. A. Ur A. Meroni A. M. Stefanini L. Corradi E. Fioretto I. V. Pokrovskiy B. Guiot A. Gadea J. J. Valiente-Dobón F. Della Vedova R. Orlandi E. Sahin D. R. Napoli L. Berti N. Toniolo S. Szilner M. Trotta M. Romoli M. La Commara D. Pierroutsakou M. Sandoli G. Pollarolo G. Benzoni 《The European physical journal. Special topics》2007,150(1):359-361
PRISMA is a magnetic
spectrometer installed at Laboratori Nazionali di Legnaro (Italy)
and designed for A=100–200, E=5–10 MeV-per-nucleon beams, and for
possible use with the proposed radioactive beam facility SPES. The
foremost features of the instrument are presented, along with the
outline of two data analyses exemplifying the effectiveness of
PRISMA-CLARA in studies of reaction
dynamics. 相似文献
4.
Electrosprays have diverse applications including protein analysis, electrospinning, and nanoencapsulation for drug delivery. We show that a variety of electrospray regimes exhibit fundamental analogy with the nonlinear dynamics of a dripping faucet. The applied voltage in electrosprays results in additional period doublings and temporal order-chaos-order transitions. Attractors in the return maps show logarithmic self-similarity in time, suggesting self-similar capillary waves on the meniscus. The bifurcations in ejection time can be explained by phase variations between capillary waves and pinch-off conditions and by ejection mode changes due to contact angle variations. 相似文献
5.
A. Vertes G. Luo L. Ye Y. Chen I. Marginean 《Applied Physics A: Materials Science & Processing》2004,79(4-6):823-825
Recent internal energy (IE) measurements for various analytes in matrix-assisted laser desorption ionization (MALDI) have indicated that the amount of IE transferred to analytes not only depends on the matrix but also on the nature of the analyte. Common matrixes, such as -cyano-4-hydroxycinnamic acid (CHCA), 3,5-dimethoxy-4-hydroxycinnamic acid (sinapinic acid, SA), and 2,5-dihydroxy-benzoic acid (DHB), had been characterized as cold or hot according to the IEs of analyte ions produced in the corresponding MALDI plume. In this contribution, we present evidence that IE transfer in MALDI depends on the matrix, analyte, as well as on the laser pulse properties. A substituted benzylpyridinium salt as a thermometer molecule (TM) was investigated in CHCA, SA, and DHB matrixes. A nitrogen laser (4 ns pulse length) and a mode locked frequency tripled Nd:YAG laser (22 ps pulse length) were used as excitation sources at various fluences. Survival yields (SYs) of the analyte molecular ions were extracted from the spectra and the corresponding IEs were obtained from Rice–Ramsperger–Kassel–Marcus (RRKM) theory. The SYs indicate that the IEs of analyte ions in MALDI are analyte, matrix, and laser source dependent. The ion generation threshold fluences follow the same order for both lasers: CHCA<SA<DHB, but for the analyte the mode locked 3× Nd:YAG laser source requires a higher threshold fluence than the nitrogen laser. Despite the higher fluence, the SYs are generally higher (the corresponding IEs are lower) for the 3× Nd:YAG laser than for the nitrogen laser. The SYs of the TM molecular ions decrease with an increase of fluence for both the ns laser and the ps laser. PACS 82.80.Ms; 82.20.Nk; 81.15.Fg 相似文献
6.
D. L. Balabanski M. Ionescu-Bujor A. Iordachescu D. Bazzacco F. Brandolini D. Bucurescu S. Chmel M. Danchev M. De Poli G. Georgiev H. Haas H. Hübel N. Marginean R. Menegazzo G. Neyens P. Pavan G. Rainovski C. Rossi Alvarez C. A. Ur K. Vyvey S. Frauendorf 《The European Physical Journal A - Hadrons and Nuclei》2003,20(1):191-192
The quadrupole interaction of high-spin isomers in 193Pb implanted into solid Hg cooled at a temperature T = 170 K has been investigated by the time-differential perturbed
-ray angular-distribution method. Spectroscopic quadrupole moment values of
eb and 0.45(4) eb have been deduced for the 21/2- and 33/2 + three-neutron states, respectively. A much higher value
eb has been determined for the 29/2- isomer, the band head of a magnetic rotational band.Received: 4 November 2002, Published online: 2 March 2004PACS:
21.10.Ky Electromagnetic moments - 27.80. + w
相似文献
7.
G. de Angelis T. Martinez A. Gadea N. Marginean E. Farnea E. Maglione S. Lenzi W. Gelletly C.A. Ur D.R. Napoli Th. Kroell S. Lunardi B. Rubio M. Axiotis D. Bazzacco A.M. Bizzeti Sona P.G. Bizzeti P. Bednarczyk A. Bracco F. Brandolini F. Camera D. Curien M. De Poli O. Dorvaux J. Eberth H. Grawe R. Menegazzo G. Nardelli J. Nyberg P. Pavan B. Quintana C. Rossi Alvarez P. Spolaore T. Steinhart I. Stefanescu O. Thelen R. Venturelli 《The European Physical Journal A - Hadrons and Nuclei》2001,12(1):51-55
Gamma ray transitions de-exciting states in the N = Z nucleus 70Br have been identified for the first time using the GASP and EUROBALL arrays coupled with ancillary detectors. The level
scheme of 70Br has been established by means of particle-gated γ-γ and γ-γ-γ coincidences. The Coulomb energy differences between isobaric
analogue states in 70Br and 70Se show a deviation from the expected behaviour which could be related to dripline effects.
Received: 18 July 2001 / Accepted: 25 September 2001 相似文献
8.
C.M. Petrache G. Lo Bianco D. Bazzacco Th. Kröll S. Lunardi R. Menegazzo M. Nespolo P. Pavan C. Rossi Alvarez M. Axiotis G. de Angelis E. Farnea N. Marginean D.R. Napoli N. Blasi 《The European Physical Journal A - Hadrons and Nuclei》2001,12(2):139-141
The even-even nucleus 128Nd was studied via in-beam γ-ray spectroscopy using the 40Ca + 82Mo reaction at 190 MeV. Two new bands were observed besides the yrast one, that has been extended up to spin 34+. Configurations were assigned to the three bands by analysing their rotational properties and by comparison with the neighboring
even-even nuclei.
Received: 18 July 2001 / Accepted: 25 October 2001 相似文献
9.
IDS Collaboration M. V. Lund A. Andreyev M. J. G. Borge J. Cederkäll H. De Witte L. M. Fraile H. O. U. Fynbo P. T. Greenlees L. J. Harkness-Brennan A. M. Howard M. Huyse B. Jonson D. S. Judson O. S. Kirsebom J. Konki J. Kurcewicz I. Lazarus R. Lica S. Lindberg M. Madurga N. Marginean R. Marginean I. Marroquin C. Mihai M. Munch E. Nacher A. Negret T. Nilsson R. D. Page S. Pascu A. Perea V. Pucknell P. Rahkila E. Rapisarda K. Riisager F. Rotaru C. Sotty M. Stanoiu O. Tengblad A. Turturica P. Van Duppen V. Vedia R. Wadsworth N. Warr 《The European Physical Journal A - Hadrons and Nuclei》2016,52(10):304
10.
Jonathan T. Cox Ioan Marginean Ryan T. Kelly Richard D. Smith Keqi Tang 《Journal of the American Society for Mass Spectrometry》2014,25(12):2028-2037
Arrays of chemically etched emitters with individualized sheath gas capillaries were developed to enhance electrospray ionization (ESI) efficiency at subambient pressures. By incorporating the new emitter array in a subambient pressure ionization with nanoelectrospray (SPIN) source, both ionization efficiency and ion transmission efficiency were significantly increased, providing enhanced sensitivity in mass spectrometric analyses. The SPIN source eliminates the major ion losses of conventional ESI-mass spectrometry (MS) interfaces by placing the emitter in the first reduced pressure region of the instrument. The new ESI emitter array design developed in this study allows individualized sheath gas around each emitter in the array making it possible to generate an array of uniform and stable electrosprays in the subambient pressure (10 to 30 Torr) environment for the first time. The utility of the new emitter arrays was demonstrated by coupling the emitter array/SPIN source with a time of flight (TOF) mass spectrometer. The instrument sensitivity was compared under different ESI source and interface configurations including a standard atmospheric pressure single ESI emitter/heated capillary, single emitter/SPIN and multi-emitter/SPIN configurations using an equimolar solution of nine peptides. The highest instrument sensitivity was observed using the multi-emitter/SPIN configuration in which the sensitivity increased with the number of emitters in the array. Over an order of magnitude MS sensitivity improvement was achieved using multi-emitter/SPIN compared with using the standard atmospheric pressure single ESI emitter/heated capillary interface. Graphical Abstract
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