排序方式: 共有24条查询结果,搜索用时 15 毫秒
1.
R.C. Greenwood C.W. Reich H.A. Baader H.R. Koch D. Breitig O.W.B. Schult B. Fogelberg A. B?cklin W. Mampe T. Von Egdy K. Schreckenbach 《Nuclear Physics A》1978,304(2):327-428
The level structure of 158Gd has been studied using the prompt γ-rays and conversion electrons emitted following neutron capture in 157Gd. The γ-ray energy and intensity measurements were made using both Ge(Li) detectors and a curved-crystal spectrometer. Conversion-electron energy and intensity measurements were made using two separate magnetic spectrometers: one to measure the primary electron spectrum and the other to measure the lower energy secondary electron spectrum. Some γ-γ coincidence measurements were also made among the secondary γ-rays. From these data, a neutron separation energy of 7937.1 ± 0.5 keV has been determined for 158Gd. A level scheme containing 59 excited states with energies < 2.25 MeV, for which de-excitation modes have been identified, is proposed for 158Gd. Many of these states have been grouped into rotational bands. A total of thirteen excited rotational bands with band-head energies below 2.0 MeV are contained in the level scheme. Features of the proposed level scheme include: the Kπ = 0?, 1? and 2? octupole-vibrational bands with band-head energies of 1263, 977 and 1793 keV, respectively; the γ-vibrational band at 1187 keV; three excited Kπ = 0+ bands with band-head energies of 1196, 1452 and 1743 keV; several two-quasiparticle bands with band-head energies in keV (and Kπ assignments) of 1380 (4+), 1636 (4?), 1847 (1+), 1856 (1?), 1920 (4+) and 1930 (1+). An analysis of (d, p) reaction data is presented which permits definite two-quasiparticle configuration assignments to be made to most of these latter bands. Evidence is presented which suggests strong mixing of some two-neutron and two-proton bands. A phenomenological four-band mixing analysis is made of the energy and E2 transition-probability data for the ground-state band and the three lowest-lying excited collective positive-parity bands. Good agreement with experiment is obtained. A Coriolis-mixing analysis of the octupole bands has been carried out and good agreement with the data on level energies and E1 transition probabilities to the ground-state band has been achieved. Values of Z, the ratio of the E1 transition matrix element with ΔK = 1 to that with ΔK = 0, involving the octupole bands and the first four 0+ bands are derived. For three of these 0+ bands, absolute values of these matrix elements are deduced. An interesting alternation in the sign of Z is observed for these four 0+ bands. 相似文献
2.
Ferraz RC Fontana CR Ribeiro AP Trindade FZ Bartoloni FH Baader JW Lins EC Bagnato VS Kurachi C 《Journal of photochemistry and photobiology. B, Biology》2011,103(2):87-92
The photodynamic therapy (PDT) is a combination of using a photosensitizer agent, light and oxygen that can cause oxidative cellular damage. This technique is applied in several cases, including for microbial control. The most extensively studied light sources for this purpose are lasers and LED-based systems. Few studies treat alternative light sources based PDT. Sources which present flexibility, portability and economic advantages are of great interest. In this study, we evaluated the in vitro feasibility for the use of chemiluminescence as a PDT light source to induce Staphylococcus aureus reduction. The Photogem? concentration varied from 0 to 75 μg/ml and the illumination time varied from 60 min to 240 min.The long exposure time was necessary due to the low irradiance achieved with chemiluminescence reaction at μW/cm2 level. The results demonstrated an effective microbial reduction of around 98% for the highest photosensitizer concentration and light dose. These data suggest the potential use of chemiluminescence as a light source for PDT microbial control, with advantages in terms of flexibility, when compared with conventional sources. 相似文献
3.
R. A. Kölliker G. O. A. Liebau R. C. Lee G. Ménier I. G. Farbenindustrie A. G. H. C. Bayley G. Laubmeyer S. H. Katz A. Baader G. Ljunggren H. Hartridge S. F. Dudley F. G. Edmed R. C. Frederick H. R. Ambler T. C. Sutton P. C. Capron R. Ruyssen J. S. Haldane R. H. Makgill S. Hatta W. Scheruhn Siemens Halske A. G. W. Schiller Kretschmer J. D. Edwards 《Analytical and bioanalytical chemistry》1934,97(11-12):424-431
4.
M.R. Beitins N.D. Kramer P.T. Prokofjev J.J. Tambergs L. Jacobs G. Vandenput J.M. van den Cruyce P.H.M. van Assche D. Breitig H.A. Baader H.R. Koch 《Nuclear Physics A》1976,262(2):273-300
The excited levels of 179Hf are investigated using the thermal neutron capture γ-ray and conversion electron spectra measured with the bent crystal diffraction spectrometer in Risø and the β-spectrograph in Riga. The level scheme contains the odd parity rotational bands and . The energies of these levels and the intensity ratios of the transitions between them are calculated taking into account the rotation-particle coupling (RPC). The following even parity levels are proposed: 859.0 and 942.2 keV ; 1004.1 and 1079.2 keV ; 1186.0, 1199.2 and 1296.4 keV . The levels at 1249.8, 1269.7, 1432.9, 1482.2 and 1755.5 keV, supported by the analysis of the γγ coincidence spectrum and Ge(Li) singles data, are discussed. 相似文献
5.
Chemiexcitation Efficiency of Intermolecular Electron‐transfer Catalyzed Peroxide Decomposition Shows Low Sensitivity to Solvent‐cavity Effects 下载免费PDF全文
Muhammad Khalid Sergio P. de Souza Jr. Fernando H. Bartoloni Felipe A. Augusto Wilhelm J. Baader 《Photochemistry and photobiology》2016,92(4):537-545
Intermolecular chemically initiated electron exchange luminescence (CIEEL) systems are known to possess low chemiluminescence efficiency; whereas, the corresponding intramolecular transformations are highly efficient. As the reasons for this discrepancy are not known, we report in this work our studies of the solvent‐cavity effect on the efficiency of two intermolecular CIEEL systems, the catalyzed decomposition of diphenoyl peroxide and of a relatively stable 1,2‐dioxetanone derivative, spiro‐adamantyl‐1,2‐dioxetanone. The results indicate a very low medium viscosity effect on the quantum yields of these systems, a priori not compatible with these bimolecular transformations, showing also that their low efficiency cannot be due to solvent‐cavity escape of intermediate radical ion pairs. In addition, the solvent‐cage effect on the CIEEL efficiency, after the occurrence of the initial electron transfer, proved also to be very low, indicating the intrinsic low viscosity effect on the chemiexcitation step. Therefore, it is concluded that the low efficiency of these systems is intrinsic to the chemiexcitation step and cannot be improved by medium viscosity effects, being possibly due to sterical hindrance on charge‐transfer complex formation in the initial step of the CIEEL. 相似文献
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7.
M. Marder E. Katz D. S. Davis P. S. Panjutin W. N. Tischkowa Office Central de Chauffe Rationelle R. Koetschau J. I. Fogelsson F. Chierer J. G. Ssemenido B. B. Krol W. P. Nikolskaja M. Richter A. Balada A. K. Tschertawskich H. Levin A. Baader H. Steinbrecher und H. Kühne 《Fresenius' Journal of Analytical Chemistry》1938,115(5-6):232-239
Ohne Zusammenfassung 相似文献
8.
M. Marder E. Katz D. S. Davis P. S. Panjutin W. N. Tischkowa R. Koetschau J. I. Fogelsson F. Chierer J. G. Ssemenido B. B. Krol W. P. Nikolskaja M. Richter A. Balada A. K. Tschertawskich H. Levin A. Baader H. Steinbrecher H. Kühne Office Central de Chauffe Rationelle 《Analytical and bioanalytical chemistry》1938,115(5-6):232-239
9.
Baader 《Fresenius' Journal of Analytical Chemistry》1927,72(5):209
Ohne Zusammenfassung 相似文献
10.
Franz Baader 《Semigroup Forum》1987,36(1):127-145
We have classified all varieties of idempotent semigroups with respect to the unification types of their defining sets of
identities. With the exception of eight finitary unifying theories these are all of unification type zero. This yields countably
many examples of theories of that type which are more “natural” than the first example constructed by Fages and Huet [9, 10]. 相似文献