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941.
M. Sandoli A. Boiano L. Campajola A. De Rosa A. D'Onofrio G. Inglima M. La Commara A. Ordine D. Pierroutsakou V. Roca M. Romano M. Romoli M. Trotta F. Rizzo F. Amorini S. Tudisco 《The European Physical Journal A - Hadrons and Nuclei》1999,6(3):275-288
We report on the results obtained from the study of the 32S +74Ge deep inelastic reaction at incident energy E= 320 MeV. High-energy γ-rays were detected in an array of 6 seven-pack BaF2 clusters. Coincidence with complex fragments detected in 12 three-stage telescopes ensured the selection of peripheral reaction
events. In order to investigate the pre-equilibrium dipole strength excitation two independent analyses were performed. In
the first analysis the energy spectra of the γ-rays were evaluated in the statistical model framework while in the second
one the γ-ray fragment angular correlation with respect to the nuclear spin vector of the composite system was studied. Both
methods indicate the excitation of dipole strength in the highly deformed dinucleus and provide dipole resonance parameter
sets that are in good agreement with each other.
Received: 24 March 1999 / Revised version: 17 May 1999 相似文献
942.
地塞米松对胃癌细胞核骨架-中间纤维系统的影响 总被引:1,自引:0,他引:1
本文应用选择性抽提整装电镜观察,研究地塞米松诱导人胃癌MGc80-3细胞分化过程中细胞核骨架-中间纤维系统的构型变化。MGc80-3细胞核骨架纤维和中间纤维数量较少、分布不均匀,核纤层为厚薄不一结构,与两类纤维联系不密切。经10μg/mlDex处理后,细胞核骨架纤维和中间纤维数量增多、结构层次丰富、单丝成份多,分布均匀并相互交织成规则网络,两类纤维通过薄层均一的核纤层密切联系,形成贯穿整个细胞核质 相似文献
943.
J. Müller 《Constructive Approximation》1999,15(4):523-536
Taylor sections S
n
(f) of an entire function f often provide easy computable polynomial approximants of f . However, while the rate of convergence of (S
n
(f))
n
is nearly optimal on circles around the origin, this is no longer true for other plane sets as, for example, real compact
intervals. The aim of this paper is to construct for certain families of (entire) functions sequences of polynomial approximants
which are computable with essentially the same effort as Taylor sections and which have a better rate of convergence on some
parts of the plane. The resulting method may be applied, for example, to (modified) Bessel functions, to confluent hypergeometric
functions, or to parabolic cylinder functions.
October 2, 1997. Date revised: March 12, 1998. Date accepted: April 28, 1998. 相似文献
944.
彭志刚 《数学物理学报(B辑英文版)》1999,19(4):457-462
1Intr0ducti0nLetAden0tethesetofallfunctionsanalyticinA={z:Izl<1}.LetB={W:WEAandIW(z)l51}.Aisalocallyconvexlineaztop0l0gicalspacewithrespecttothetopologyofuniformconvergenceon`c0mpact8ubsetsofA-LetTh(c1,'tc.-1)={p(z):p(z)EA,Rop(z)>0,p(z)=1 clz czzz ' c.-lz"-l 4z" ',wherecl,',cn-1areforedcomplexconstants}.LetTh,.(b,,-..,b,-,)={p(z):P(z)'EAwithReP(z)>Oandp(z)=1 blz ' b.-lz"-l 4z" '-,wherebl,-'-jbu-1areffeedrealconstantsanddkarerealnumbersf0rk=n,n 1,'--}-LetTu(l1,'i'tI.-1)={… 相似文献
945.
本文给出了代数A与双代数H的Smash积AH是A的超限左自由正规化扩张的一个充分条件.进一步,主要结果被运用到斜半群环、斜群环和量子群Uq(sl(2))从而给出了它们的一些性质. 相似文献
946.
王梦 《浙江大学学报(理学版)》1999,26(4):1-7
本文讨论了乘积域Rn×Rm上一类带粗糙核的奇异积分算子的Lp(Rn×Rm)有界性。这里,Ω为原子Hardy空间H1a(Sn-1×Sm-1)中的函数,h为L∞(Lq)(R+×R+)中的径向函数,Φ(t)满足一定的增长条件。 相似文献
947.
D. Barrios Rolanía G. Lpez Lagomasino H. Pijeira Cabrera 《Journal of Approximation Theory》1999,100(2):104
The concepts of definite and determinate Sobolev moment problem are introduced. The study of these questions is reduced to the definiteness or determinacy, respectively, of a system of classical moment problems by means of a canonical decomposition of the moment matrix associated with a Sobolev inner product in terms of Hankel matrices. 相似文献
948.
949.
The polarographic behavior and catalytic wave mechanism of medroprogesterone acetate (MPA) were studied in both aqueous and DMF media. In 0.2 mol/L acetic acid-sodium acetate (pH 5.0) buffer solution, the C=C bond of MPA first undergoes le, lH~ reduction to form protonated free radical HMPA(?), the further reduction of HMPA(?) in le, 1H~ process is simultaneous with the dimerization reaction between HMPA(?) and neutral molecular MPA. In DMF media containing 0.1 mol/L tetrabutylammonium tetrafluoborate (TBA·BF_4), the C=C bond of MPA shows two le, 1H~ reduction waves, which are ascribed to the reduction of MPA and free radical MPA, respectively. Here, no dimerization reaction occurs. These processes produce the reduction wave of MPA. In the presence of oxidant KIO_3, a polarographic catalytic wave of MPA is observable due to a chemical reaction between HMPA(?) or MPA(?) and KIO_3 as well as its intermediate species to regenerate MPA. The catalytic wave, which is caused by the reduction of organic com 相似文献
950.
Korin E. Soifer L. Mogiliyanskii D. Soifer Ya. Brodova I. Manuhin A. 《Journal of Thermal Analysis and Calorimetry》1999,58(3):663-669
Crystallization kinetics of Mg84Ni12.5Y3.5 amorphous ribbons produced by the melt-spinning method, was studied by DSC analysis and X-ray diffraction. The effect of heating rate (from 2 to 240 K min–1) was investigated in the temperature range from 298 to 673 K. The results showed that the crystallization process took place in two stages: a) crystallization of part of the amorphous matrix to an intermediate phase and hcp-Mg, and b) transformation of the intermediate phase and the remaining amorphous material to Mg2Ni+Mg (solid solution of Y in Mg). Increasing the heating rate from 2 to 240 K min–1 results in increases of the temperature difference between the two-step crystallization of the first stage transformation processes from 33 to 56 K and in increases of the temperature difference between the two-stage transformation from 62 to 97 K.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献