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101.
采用高效液相色谱法对某保健酒中淫羊藿苷成分进行分析研究,结果表明,保健酒中淫羊藿苷的平均含量为0.627%,平均回收率为98.1%,相对标准差(RSD)为2.1%.本分析方法也适用于其他保健酒、药材和药品中淫羊藿苷成分的分析测定. 相似文献
102.
Since its discovery in 1946, NMR has become a valuable tool in physics, chemistry, biology, and medicine. With the invention of NMR logging tools that take the medical MRI or laboratory NMR equipment and turn it inside-out, the application of sophisticated laboratory techniques to determine formation properties in situ is now available. The capability has opened a new era in formation evaluation just as the introduction of NMR has revolutionized the other scientific areas. 相似文献
103.
Based on the measured transverse mass spectra ofπr-, K-, and p at the RHIC energy s()NN = 130 GeV,di-omega productions from baryon-baryon reactions in hadronic matter are studied. Results about the (ΩΩ)0+ numbershow that the deeply bound state (ΩΩ)o+ can be observed at RHIC energies. 相似文献
104.
105.
V. P. Kondilenko V. Ya. Chorny A. M. Eremenko 《Reaction Kinetics and Catalysis Letters》1993,50(1-2):203-207
The influence of temperature in the 20–100°C range on processes of bimolecular interaction in the aerosil-phenanthrene-trinitrobenzene system has been studied. Temperature-stimulated CTC accumulation on the surface is found. Activation energies of complex formation are estimated. Quenching of phenanthrene fluorescence by acceptor has a mixed static and dynamic character. 相似文献
106.
107.
S. Ya. Yakubov 《Results in Mathematics》1995,28(1-2):153-168
In this paper we find conditions guarantee that irregular boundary value problems for elliptic differential-operator equations of the second order in an interval are fredholm. We apply this result to find some algebraic conditions guarantee that irregular boundary value problems for elliptic partial differential equations of the second order in cylindrical domains are fredholm. Apparently this is the first paper where the regularity of an elliptic boundary value problem is not satisfied on a manifold of the dimension equal to dimension of the boundary. Nevertheless the problem is fredholm and the resolvent is compact. It is interesting to note that the considered boundary value problems for elliptic equations in a cylinder being with separating variables are noncoercive. 相似文献
108.
109.
E. Ya. Paryev 《Physics of Atomic Nuclei》2006,69(2):332-354
Within the spectral function approach, we study the direct production and decay via the dikaon (dimuon) channel of ϕ mesons
in the interactions of 2.4-and 2.7-GeV protons with light and medium target nuclei. It is shown that the K
+
K
− (μ+ μ−) invariant-mass distribution consists of the two components, which correspond to the ϕ decay “outside” and “inside” the target nucleus. The first (narrow) component has the free ϕ width, while the second (broad) component is distorted by the nuclear matter owing to resonance-nucleon scattering and a
possible in-medium modification of the kaons and ρ meson at finite baryon density. The relative strength of the “inside” and “outside” components is analyzed in different scenarios
for the ϕ width and momentum cut. It is demonstrated that the width of the resulting dimuon invariant-mass distribution on medium nuclei
is larger than the free ϕ width by a factor of about 2 if the total ϕ in-medium width is used and the respective cutoff for the ϕ three-momentum is applied, whereas the resulting dikaon invariant-mass distribution has an insignificant sensitivity to the
ϕ in-medium properties owing to the strong absorption of the K
− in the surrounding nuclear matter. On the other hand, because of the distortion of the K
+ and K
− on their way out of the target nucleus mainly due to the hadronic kaon potentials, the latter distribution is broadened and
shifted to higher invariant masses, which means that the measurement of such broadening would give additional evidence for
the modification of the kaon and antikaon properties in the nuclear medium.
The text was submitted by the author in English. 相似文献
110.
Outline imaging by THz time domain spectroscopy is proposed. Spectroscopic splitting at interface is reported, The principle of outline imaging is put forward. Experimental results demonstrate the feasibility of outline imaging by spectroscopic splitting, It is shown that clear out:line image of sample interface could be achieved easily by this technique. The spatial resolution is about 0.6mm. The THz-beam focus, the scanning step and the THz pulse width are the critical foctors affecting the imaging resolution. The signal-to-noise ratio of this technique could be improved greatly compared to the conventional transsion imaging. 相似文献