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91.
We show that non-Hermitian and nearest-neighbor-interacting perturbations to the Fritzsch textures of lepton and quark mass matrices can make both of them fit current experimental data very well. In particular, we obtain θ23?45° for the atmospheric neutrino mixing angle and predict θ13?3° to 6° for the smallest neutrino mixing angle when the perturbations in the lepton sector are at the 20% level. The same level of perturbations is required in the quark sector, where the Jarlskog invariant of CP violation is about 3.7×10−5. In comparison, the strength of leptonic CP violation is possible to reach about 1.5×10−2 in neutrino oscillations. 相似文献
92.
Hiroyasu Ejiri 《Progress in Particle and Nuclear Physics》2010,64(2):249-257
Neutrino-less double beta decays (0νββ), which violate the lepton number conservation law by ΔL=2, are unique and realistic probes for studying the Majorana nature of neutrinos, the ν mass spectrum and the absolute mass scale, the lepton sector CP and others beyond the standard electro-weak theory. Neutrino nuclear responses (nuclear matrix elements M0ν) are crucial to extract neutrino properties of the particle physics interests from experimental 0νββ rates. Subjects discussed include 0νββ processes and Majorana neutrinos, the present and future 0νββ experiments, and neutrino nuclear responses (M0ν) and charge exchange reactions. 相似文献
93.
J. Dilling G. Audi D. Beck G. Bollen F. Herfurth A. Kellerbauer H.-J. Kluge D. Lunney R.B. Moore C. Scheidenberger S. Schwarz G. Sikler J. Szerypo 《Hyperfine Interactions》2001,132(1-4):329-333
The masses of the xenon isotopes with 114≤A≤123 were directly measured for the first time. The experiments were carried out at the ISOLTRAP triple trap spectrometer
at the on-line mass separator ISOLDE/CERN. A mass resolving power of the Penning trap spectrometer of m/Δm≈500 000 was chosen and an accuracy of δm≈12keV for all investigated Xe isotopes was achieved. An atomic mass evaluation was performed and the results of this adjustment
are compared with theoretical predictions. The new results for the xenon isotopes and their effects on neighboring nuclides
are discussed within the two-neutron separation energy picture.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
94.
Electromagnetic mass difference between neutral K* and charged K* has been calculated in the U(3)L×U(3)R chiral field theory of mesons. It has been revealed that the on-Abelian gauge structure of the massive Yang-Mills Lagrangian obeyed by K* plus VMD (vector meson dominance) causes the EM-mass of neutral one larger than charged one. Experiment supports this anomaly effect. 相似文献
95.
硒试剂光度法测定钢铁及加硒碘盐中的微量硒 总被引:1,自引:0,他引:1
以3,3'-二氨基联苯胺(硒试剂)作显色剂,加足量乙二胺四乙酸二钠(EDTA)掩蔽铁等金属离子,在pH为2-3的甲酸介质中显色,在pH为6-7时,用甲苯萃取硒(Ⅳ)-硒试剂络合物。当溶液中的硒(Ⅳ)含量大于20μg/10mL时,不用萃取硒(Ⅳ)-硒试剂络合物,直接测定。该方法用于钢铁及加硒碘盐中微理硒的测定,结果满意。 相似文献
96.
Yu.Ts. Oganessian A.V. Yeremin G.G. Gulbekian S.L. Bogomolov V.I. Chepigin B.N. Gikal V.A. Gorshkov M.G. Itkis A.P. Kabachenko V.B. Kutner A.Yu. Lavrentev O.N. Malyshev A.G. Popeko J. Roháč R.N. Sagaidak S. Hofmann G. Münzenberg M. Veselsky S. Saro N. Iwasa K. Morita 《The European Physical Journal A - Hadrons and Nuclei》1999,5(1):63-68
The reaction 48Ca+238U was investigated at the recoil separator VASSILISSA at the Flerov Laboratory of Nuclear Reactions, JINR Dubna, in attempts
to synthesize new isotopes of element 112. The experiments were performed at two beam energies resulting in excitation energies
of the compound nucleus of 33 and 39 MeV. The collected beam dose was 3.5 × 1018 and 2.2 × 1018, respectively. Two spontaneous fission events were observed at the lower beam energy, which tentatively were assigned to
the new neutron rich isotope 283112 produced in the reaction 238U(48Ca,3n)283112. The measured cross-section is (5.0+6.3
−3.2) pb and the half–life is (81+147
−32) s. No event was observed at the higher beam energy resulting in the upper cross–section limit of 7.3 pb.
Received: 12 October 1998 / Revised version: 12 January 1999 相似文献
97.
R. Sherr H.T. Fortune B.A. Brown 《The European Physical Journal A - Hadrons and Nuclei》1999,5(4):371-372
Despite a recent suggestion of Chulkov, et al., we find no evidence for a tetra-proton cluster in 20Mg. The binding energy and radius are easily understood without such a cluster.
Received: 14 May 1999 相似文献
98.
99.
超高效液相色谱法同时测定减肥类保健食品中非法添加的25种药物 总被引:6,自引:0,他引:6
建立了采用超高效液相色谱同时测定减肥类保健食品中25种非法添加化学药物含量的方法。保健食品样品以甲醇为提取溶剂进行超声提取,离心后取上清液以Waters HSS T3色谱柱(100 mm×2.1 mm,1.8 μm)进行分离,乙腈和10 mmol/L乙酸铵水溶液(含0.1%甲酸)为流动相梯度洗脱,流速为0.3 mL/min,在200~400 nm波长范围内进行定性和定量分析。在相应的浓度范围内,25种化学药物的质量浓度与峰面积呈良好的线性关系,R2≥0.997;定量限在0.500~5.00 ng之间;在低、中、高3个添加水平范围内的平均回收率为70.7%~104%,相对标准偏差(RSD)在0.132%~5.03%之间。样品筛查结果发现,17种减肥保健食品中3种样品非法添加了酚酞,1种样品添加了大黄素。该方法选择性强、分析速度快、高通量,可用于该类保健食品中非法添加化学药品的定性筛查和定量检测。 相似文献
100.
D. Lunney G. Audi C. Gaulard M. de Saint Simon C. Thibault N. Vieira 《The European Physical Journal A - Hadrons and Nuclei》2006,28(2):129-138
High-precision mass measurements have been performed on the exotic magnesium isotopes 29-33Mg using the MISTRAL radiofrequency spectrometer, especially suited for very short-lived nuclides. This method, combined with
the powerful tool of resonant laser ionization at ISOLDE, has provided a significant reduction of uncertainty for the masses
of the most exotic Mg isotopes: a relative error of 7×10-7 was achieved for the weakly produced 33Mg that has a half-life of only 90ms. Moreover, the mass of 33Mg is found to change by over 250keV. Verifying and minimizing binding energy uncertainties in this region of the nuclear
chart is important for understanding the lack of binding energy that is normally associated with magic numbers. 相似文献