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61.
Palanisamy Saravanakumar Nallathambi Ashok Kumar Specht Eckehard 《Journal of Thermal Analysis and Calorimetry》2020,141(6):2665-2671
Journal of Thermal Analysis and Calorimetry - At the end of the hot rolling process, quenching is deployed for obtaining the desired microstructure and mechanical properties. During the quenching... 相似文献
62.
63.
Arnaldi R Averbeck R Banicz K Castor J Chaurand B Cicalò C Colla A Cortese P Damjanovic S David A De Falco A Devaux A Drees A Ducroux L En'yo H Fargeix J Ferretti A Floris M Förster A Force P Guettet N Guichard A Gulkanian H Heuser JM Keil M Kluberg L Lourenço C Lozano J Manso F Masoni A Martins P Neves A Ohnishi H Oppedisano C Parracho P Pillot P Puddu G Radermacher E Ramalhete P Rosinsky P Scomparin E Seixas J Serci S Shahoyan R Sonderegger P Specht HJ Tieulent R Usai G Veenhof R 《Physical review letters》2006,96(16):162302
We report on a precision measurement of low-mass muon pairs in 158 AGeV indium-indium collisions at the CERN SPS. A significant excess of pairs is observed above the yield expected from neutral meson decays. The unprecedented sample size of 360,000 dimuons and the good mass resolution of about 2% allow us to isolate the excess by subtraction of the decay sources. The shape of the resulting mass spectrum is consistent with a dominant contribution from pi+pi- -->rho -->mu+mu- annihilation. The associated space-time averaged spectral function shows a strong broadening, but essentially no shift in mass. This may rule out theoretical models linking hadron masses directly to the chiral condensate. 相似文献
64.
R. Arnaldi K. Banicz K. Borer J. Castor B. Chaurand W. Chen C. Cicalò A. Colla P. Cortese S. Damjanovic A. David A. de Falco A. Devaux L. Ducroux H. En’yo J. Fargeix A. Ferretti M. Floris A. F?rster P. Force N. Guettet A. Guichard H. Gulkanian J. M. Heuser M. Keil L. Kluberg Z. Li C. Louren?o J. Lozano F. Manso P. Martins A. Masoni A. Neves H. Ohnishi C. Oppedisano P. Parracho P. Pillot T. Poghosyan G. Puddu E. Radermacher P. Ramalhete P. Rosinsky E. Scomparin J. Seixas S. Serci R. Shahoyan P. Sonderegger H. J. Specht R. Tieulent G. Usai R. Veenhof H. K. W?hri 《The European Physical Journal C - Particles and Fields》2009,61(4):711-720
The NA60 experiment at the CERN SPS has measured muon pairs with unprecedented precision in 158 A GeV In–In collisions. A strong excess of pairs above the known sources is observed in the whole mass region 0.2<M<2.6 GeV. The mass spectrum for M<1 GeV is consistent with a dominant contribution from π
+
π
−→ρ→μ
+
μ
− annihilation. The associated ρ spectral function shows a strong broadening, but essentially no shift in mass. For M>1 GeV, the excess is found to be prompt, not due to enhanced charm production, with pronounced differences to Drell–Yan pairs.
The slope parameter T
eff associated with the transverse momentum spectra rises with mass up to the ρ, followed by a sudden decline above. The rise for M<1 GeV is consistent with radial flow of a hadronic emission source. The seeming absence of significant flow for M>1 GeV and its relation to parton–hadron duality is discussed in detail, suggesting a dominantly partonic emission source
in this region. A comparison of the data to the present status of theoretical modeling is also contained. The accumulated
empirical evidence, including also a Planck-like shape of the mass spectra at low p
T
and the lack of polarization, is consistent with a global interpretation of the excess dimuons as thermal radiation. We conclude
with first results on ω in-medium effects. 相似文献
65.
Agakichiev G Baur R Breskin A Chechik R Drees A Jacob C Faschingbauer U Fischer P Fraenkel Z Fuchs C Gatti E Glässel P Günzel T de los Heros CP Hess F Irmscher D Lenkeit B Olsen LH Panebrattsev Y Pfeiffer A Ravinovich I Rehak P Schön A Schukraft J Sampietro M Shimansky S Shor A Specht HJ Steiner V Tapprogge S Tel-Zur G Tserruya I Ullrich T Wurm JP Yurevich V 《Physical review letters》1995,75(7):1272-1275
66.
U. Goerlach D. Habs M. Just V. Metag P. Paul H. J. Specht H. J. Maier 《Zeitschrift für Physik A Hadrons and Nuclei》1978,287(2):171-181
The prompt and isomeric fission probabilities of240Pu have been studied using the239Pu(d,p) reaction. A number of resonances are observed in the subbarrier population of the 4 ns fission isomer for excitation energies between 4.0 and 6.2 MeV. Apart from a structure at 4.3 MeV, they do not coincide with transmission resonances found in prompt fission. Calculations with an extended doorway state model which simultaneously reproduce the measured delayed and prompt fission probabilities yield revised fission barrier parameters as well as spectroscopic information on fission and gamma widths of highly excited states in the second minimum. 相似文献
67.
Several derivatives of 3-ketocoumarins were prepared and are shown to have many of the photophysical criteria required for efficient triplet sensitizers. These compounds include 3-aroylcoumarins (1) and 3,3′- carbonylbiscoumarins (2). The aryl groups in 1 are either phenyl and substituted phenyl derivatives or heterocyclic groups such as thienyl and benzofuryl. The substituents on the coumarin moiety in 1 and 2, if any, are alkoxy or dialkylamino. These compounds, with absorption maxima between 330 and 450 nm, have extinction coefficients in the range of 104 to almost 105, which is an important criterion for efficient sensitization of thin films of polymers as those used in photoresists and lithography. The singlet-triplet intersystem crossing (isc) efficiencies of several derivatives approach unity. In others, however, a radiationless decay process competes with the isc. The decay process is particularly dominant in the asymmetrically substituted derivatives of 2, but seems to be considerably suppressed in polymeric matrices. The triplet energies of these compounds range from ca. 48 to 60 kcal/mol. Some of these ketocoumarins show phosphorescence spectra that suggest the presence of “frozen-in” rotamers. 相似文献
68.
S. Specht R. F. Nolte H. -J. Born 《Journal of Radioanalytical and Nuclear Chemistry》1974,21(1):119-127
The importance of the extraction medium and its film geometry to the separation efficiency is illustrated by the example of
the chromatographic extraction systems HDEHP-HCl-Eu3+ and TBP-HNO3−Sc3+. Starting from the geometry of the matrix, the effects of the exchange kinetics and flow pattern were experimentally proved.
Exchange kinetics are described as a heterogeneous transport-limited reaction in the aqueous phase. Four ranges of the rate
of exchange with the geometry of the matrix (pore diameter) were found. The flow patterns in the chromatographic layer can
be established by the individual pore cross-sectional area of the matrix. The sum of the effects of exchange kinetics and
flow patterns determines the chromatographic efficiency of the systems. Their relative effects in the two systems being investigated
are discussed. 相似文献
69.
R. Henkelmann A. Huber S. Specht H. Stark 《Journal of Radioanalytical and Nuclear Chemistry》1976,32(2):265-274
The analytical use of the prompt gamma-rays originating from neutron capture is a valuable completition of the conventional
neutron activation analysis. The application of the external radiation tube P2 of the research reactor in Munich, an Am—Be
neutron source of 300 mCi and a 1 mg252Cf neutron source is discussed.
相似文献
70.
Three‐Dimensional Control of DNA Hybridization by Orthogonal Two‐Color Two‐Photon Uncaging 下载免费PDF全文
Manuela A. H. Fichte Xenia M. M. Weyel Dr. Stephan Junek Dr. Florian Schäfer Dr. Cyril Herbivo Prof. Dr. Maurice Goeldner Dr. Alexandre Specht Prof. Dr. Josef Wachtveitl Prof. Dr. Alexander Heckel 《Angewandte Chemie (International ed. in English)》2016,55(31):8948-8952
We successfully introduced two‐photon‐sensitive photolabile groups ([7‐(diethylamino)coumarin‐4‐yl]methyl and p‐dialkylaminonitrobiphenyl) into DNA strands and demonstrated their suitability for three‐dimensional photorelease. To visualize the uncaging, we used a fluorescence readout based on double‐strand displacement in a hydrogel and in neurons. Orthogonal two‐photon uncaging of the two cages is possible, thus enabling complex scenarios of three‐dimensional control of hybridization with light. 相似文献