A high yielding rice mutant ( Oryza sativa L. cv. Zhenhui 249) with low chlorophyll b was recently discovered in the field. The mutant was mainly characterized by the decrease of the content of extrinsic antennae c...A high yielding rice mutant ( Oryza sativa L. cv. Zhenhui 249) with low chlorophyll b was recently discovered in the field. The mutant was mainly characterized by the decrease of the content of extrinsic antennae complex. This variation was shown in the stage when the leaves were expanding. When the leaves are at the final developmental stage, the content would approach to that of the wild type. It was discovered that only moderate amount of chlorophyll b decreased in this mutant. The photosynthetic apparatus of the mutant was rather stable in the whole life span of the leaf. The extrinsic antennae complex of the mutant might make efficient use of light and meanwhile reduce the production of O -· 2.展开更多
In preparation of homogeneous Kr and Rb sources,the Kr activity was determined by the decay relationship between ^(88)Kr and ^(88)Rb using an HPGe detector.The peak efficiencies of ^(88)Kr and ^(88)Rbγ-rays were cali...In preparation of homogeneous Kr and Rb sources,the Kr activity was determined by the decay relationship between ^(88)Kr and ^(88)Rb using an HPGe detector.The peak efficiencies of ^(88)Kr and ^(88)Rbγ-rays were calibrated.The results show that the absolute probabilities of 196.3,834.8,1529.8,2195.8 and 2392.1 keVγ-rays of ^(88)Kr were 25.1(5)%,12.9(2)%,10.7(2)%,13.3(2)%and 34.9(5)%,respectively.展开更多
The difference of and indicates the role of the light flavors. We calculate the lifetimes of -meson and based on the weak effective Hamiltonian while assuming the heavy baryon is constructed by a heavy -quark and ...The difference of and indicates the role of the light flavors. We calculate the lifetimes of -meson and based on the weak effective Hamiltonian while assuming the heavy baryon is constructed by a heavy -quark and a diquark containing two light quarks. In this scenario, we use the information of the measured ratio as input to predict rates of the inclusive weak decays of and into non-bottom final states. We find that these rates of and are much larger than those of -mesons and . We also give the predictions for the lifetimes of and . Phenomenological implication of our result is discussed.展开更多
In this paper, we calculated the new physics contribution to theoretically very clean rare decay B → Xsvvin the general two-Higgs-doublet model (model Ⅲ). Within the considered parameter space, we found that (a) the...In this paper, we calculated the new physics contribution to theoretically very clean rare decay B → Xsvvin the general two-Higgs-doublet model (model Ⅲ). Within the considered parameter space, we found that (a) thenew physics contribution can provide one to two orders of enhancement to the branching ratio B(B → Xsvv) and cansaturate the experimental bound on B(B → Xs vv) in some regions of the parameter space; (b) besides the CLEO data ofB → Xsγ, the ALEPH upper limit on B(B → Xsvv) also leads to further constraint on the size of the Yukawa couplingλtt: λtt ＜ 6.4 for λbb = 2.7 and mH+ = 200 GeV.展开更多
The B-meson decay constant fB is an important component for studying the B-meson decays, which can be studied through QCD sum rules. We make a detailed discussion on f B from two sum rules up to next-to- leading order...The B-meson decay constant fB is an important component for studying the B-meson decays, which can be studied through QCD sum rules. We make a detailed discussion on f B from two sum rules up to next-to- leading order, i.e. sum rules I and II, which are derived from the conventional correlator and the correlator with chiral currents respectively. It is found that these two sum rules are consistent with each other. The sum rules H involves less non-perturbative condensates as that of sum rules I, and in principle, it can be more accurate if we know the dimensionfour gluon condensate well. It is found that fB decreases with the increment of mb, and to compare with the Belle experimental data on fB, both sum rules I and H prefer smaller pole b-quark mass, mb= 4.68 ± 0.07 GeV. By varying all the input parameters within their reasonable regions and by adding all the uncertainties in quadrature, we obtain fB=172-25^＋23 MeV for sum rules I and fB =214-34^26 MeV for sum rules П.展开更多
Based on the low energy effective Hamiltonian with naive factorization, we calculate the branching ratios （BRs） and CP asymmetries （CPAs） for the twenty three double charm decays B/B8 → D（＊）D（＊） in both the...Based on the low energy effective Hamiltonian with naive factorization, we calculate the branching ratios （BRs） and CP asymmetries （CPAs） for the twenty three double charm decays B/B8 → D（＊）D（＊） in both the standard （s） （s） model （SM） and the minimal supergravity （mSUGRA） model. Within the considered parameter space, we find that （a） the theoretical predictions for the BRs, CPAs and the polarization fractions in the SM and the mSUGRA model are all consistent with the currently available data within ±2σ errors; （b） For all the considered decays, the supersymmetric contributions in the mSUGRA model are very small, less than 7% numerically. It may be difficult to observe so small SUSY contributions even at LHC.展开更多
文摘A high yielding rice mutant ( Oryza sativa L. cv. Zhenhui 249) with low chlorophyll b was recently discovered in the field. The mutant was mainly characterized by the decrease of the content of extrinsic antennae complex. This variation was shown in the stage when the leaves were expanding. When the leaves are at the final developmental stage, the content would approach to that of the wild type. It was discovered that only moderate amount of chlorophyll b decreased in this mutant. The photosynthetic apparatus of the mutant was rather stable in the whole life span of the leaf. The extrinsic antennae complex of the mutant might make efficient use of light and meanwhile reduce the production of O -· 2.
文摘In preparation of homogeneous Kr and Rb sources,the Kr activity was determined by the decay relationship between ^(88)Kr and ^(88)Rb using an HPGe detector.The peak efficiencies of ^(88)Kr and ^(88)Rbγ-rays were calibrated.The results show that the absolute probabilities of 196.3,834.8,1529.8,2195.8 and 2392.1 keVγ-rays of ^(88)Kr were 25.1(5)%,12.9(2)%,10.7(2)%,13.3(2)%and 34.9(5)%,respectively.
文摘The difference of and indicates the role of the light flavors. We calculate the lifetimes of -meson and based on the weak effective Hamiltonian while assuming the heavy baryon is constructed by a heavy -quark and a diquark containing two light quarks. In this scenario, we use the information of the measured ratio as input to predict rates of the inclusive weak decays of and into non-bottom final states. We find that these rates of and are much larger than those of -mesons and . We also give the predictions for the lifetimes of and . Phenomenological implication of our result is discussed.
基金国家自然科学基金，the Research Foundation ofNanjing Normal University under
文摘In this paper, we calculated the new physics contribution to theoretically very clean rare decay B → Xsvvin the general two-Higgs-doublet model (model Ⅲ). Within the considered parameter space, we found that (a) thenew physics contribution can provide one to two orders of enhancement to the branching ratio B(B → Xsvv) and cansaturate the experimental bound on B(B → Xs vv) in some regions of the parameter space; (b) besides the CLEO data ofB → Xsγ, the ALEPH upper limit on B(B → Xsvv) also leads to further constraint on the size of the Yukawa couplingλtt: λtt ＜ 6.4 for λbb = 2.7 and mH+ = 200 GeV.
基金Supported by Natural Science Foundation Project of CQ CSTC under Grant No.2008BB0298by Natural Science Foundation of China under Grant Nos.10805082 and 11075225by the Fundamental Research Funds for the Central Universities under Grant No.CDJZR101000616
文摘The B-meson decay constant fB is an important component for studying the B-meson decays, which can be studied through QCD sum rules. We make a detailed discussion on f B from two sum rules up to next-to- leading order, i.e. sum rules I and II, which are derived from the conventional correlator and the correlator with chiral currents respectively. It is found that these two sum rules are consistent with each other. The sum rules H involves less non-perturbative condensates as that of sum rules I, and in principle, it can be more accurate if we know the dimensionfour gluon condensate well. It is found that fB decreases with the increment of mb, and to compare with the Belle experimental data on fB, both sum rules I and H prefer smaller pole b-quark mass, mb= 4.68 ± 0.07 GeV. By varying all the input parameters within their reasonable regions and by adding all the uncertainties in quadrature, we obtain fB=172-25^＋23 MeV for sum rules I and fB =214-34^26 MeV for sum rules П.
基金Supported by the National Natural Science Foundation of China under Grant Nos. 10947020 and 11005033Foundation of Henan Educational Committee for Youth Backbone Scholars in Colleges and Universities+1 种基金the Natural Science Foundation of the Eduction Department of Henan Province under Grant No. 2010A140012Natural Science Foundation of Henan Province under Grant No. 102300410210
文摘Based on the low energy effective Hamiltonian with naive factorization, we calculate the branching ratios （BRs） and CP asymmetries （CPAs） for the twenty three double charm decays B/B8 → D（＊）D（＊） in both the standard （s） （s） model （SM） and the minimal supergravity （mSUGRA） model. Within the considered parameter space, we find that （a） the theoretical predictions for the BRs, CPAs and the polarization fractions in the SM and the mSUGRA model are all consistent with the currently available data within ±2σ errors; （b） For all the considered decays, the supersymmetric contributions in the mSUGRA model are very small, less than 7% numerically. It may be difficult to observe so small SUSY contributions even at LHC.
