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991.
A microscopic study of nucleon-antinucleon (N N) bound states is achieved starting from the relativistic Pauli-Schrödinger equation for q3q3 bound states. From this equation, a complex off-shell qq one-gluon-exchange potential is derived. Use of this potential and the resonating group method to calculate the NN bound states leads to results which are useful to analyze some of the NN experimental data reported in recent years. 相似文献
992.
Reported here is identification of a 7-en-sterol and a 5-en-sterol which containsa cyclopropane ring in its side chain and is separated from the South China Seasponge Biemna sp..This leads to the isolation and identification of twelve sterols inthis marine sponge by using gas chromatography-mass spectrometry (GC-MS)analysis.The occurrence of 7-en-sterol and 5-en-sterol with a cyclopropane ring inits side chain from the south China Sea sponge was first reported here. 相似文献
993.
SU Qiao-Juan ZHANG Hong-bin ZHOU Tai-jin LIU Yu-da LIN Guo-dong TSAI Khi-rui 《高等学校化学研究》1995,11(1):50-57
EHMOStudiesofChemisorbedDioxygenSpeciesonNa_2OandK_2OandofTheirInteractionwithCH_4andCH_3-RadicalSUQiao-Juan,ZHANGHong-bin,ZH... 相似文献
994.
The thermodynamic properties of superconducting state in BZA mean-field theory of RVB superconducting mechanism are evaluated in this letter. 相似文献
995.
In this paper, the quark-antiquark one gluon exchange potential corresponding to the annihilation channels is calculated to the order of p2/m2 by means of Fierz reordering transformation. The nucleon-antinucleon effective potential obtained from one gluon exchange potential has a strong attraction at a short distance as expected in the meson-exchange theory. 相似文献
996.
Starting with the QCD generating functional, a new derivation and a new form of the Dirac-Schriidinger (D-S) equation,catisfied by the equal-time Bethe-Salpeter amplitude of quark-antiquark bound states have been given. In this equation, the effective interaction kernel has a compact expression and can be directly calculated by means of the conventional QCD Feynman rules. F'urthermore, an equivalent reduction of the above equation to a Pauli-Schriidinger equation has also been achieved and a closed form of the effective interaction Hamiltonian appearing in the latter equation has been explicitly written out. 相似文献
997.
We discuss the CP violation problem of SU(7) models of Grand Unified Theoryincluding four genarations[1,2]. It is shown that if we properly choose the complex phaseangles in quark mass matrix elements, we are able to obtain the CP violation phaseangle which agrees well with the experimental value. If the Higgs potential is pro-perly choosen we find that the strong CP violation parameter θ is equal to zero atthe tree level. 相似文献
998.
The distributions of dynamic variables in the deep inelastic scattering (DIS) of heavy-ions are studied by a direct simulation technique based on the single-nucleon-transfer-mechanism. The relative motion of the two collision partners is described by a Lagrange equation, and the transition probability of a single nucleon during the interaction time is calculated by the statisti-cal spectroscopy method.The occurrence of the transition event and the corresponding change of the dynamic variables are both treated randomly according to the transition probability. The calculated results for the reaction of 40Ar+58Ni(EL=280MeV) are compared with experimental data. 相似文献
999.
ON THE DYSON EQUATION AND THE WARD-TAKAHASHI IDENTITIES OF THE CLOSED TIME PATH GREEN'S FUNCTIONS 下载免费PDF全文
The Dyson equation satisfied by the closed time path Green's function of the or-der parameters is considered.The transport equation for the number density of thequasi-particles is written down in a general but simple form.Using the path integ-ral formulation for the generating functional of these Green's functions,the Ward-Takahashi identities are deduced. 相似文献
1000.
THE VERTICAL INTEGRATED MOMENTUM SPECTRUM OF THE MUON WITH MOMENTUM LARGER THAN 4 GeV/c AT 3220m ABOVE SEA-LEVEL 下载免费PDF全文
JING GUI-RU HUO AN-XIANG YAN YU-KUI WANG LI-AN LI YAN-GUO SU DENG-JI MENG XIANG-CHENG YAO WEI-ZHONG ZHOU YIN-ZAO PENG SHAO-HUA WANG LI-HUI 《中国物理C(英文版)》1978,2(5):417-422
At an altitude of 3220 meters above sea level in Yunnan Province, we measured, by using a G-M counter-magnetic spectrometer, the vertical integratted momentum spectrum of the cosmic muon with momentum larger than 4 GeV/c. The spectrum obtained from this experiment is expressed by a power function in the form of I(>p)=Q (p+4)-1.86±0.06(cm-2·sr-1·s-1), where p is in GeV/c and Q is a constant. We also measured the charge ratio of muon in the 4—23 GeV/c momentum range. The result is Nμ/Nμ-=1.26±0.11. The error in the momentum measurement with spectrometer has been discussed and calculated. 相似文献