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911.
The difference in the bandhead moments of inertia between the superdeformed (SD) band194Hg(1) and the two-quasiparticle SD bands194Hg(2, 3) was investigated using the particle-number-conserving treatment for the cranked shell model Hamiltonian. and the
pairing interaction strength in SD nuclei is estimated to be much weaker than that in normally deformed nuclei. 相似文献
912.
Summary A polarographic method for the determination of bilirubin is described: In hydroquinone-sodium phosphate buffer (pH 11.2) medium, bilirubin can be rapidly oxidized to a green product, which causes a sensitive polarographic wave at –0.83 V (vs. SCE); the peak current of the wave is linear with the bilirubin concentration over a range of 3×10–7 to 5×10–6 mol/l. It has also been found to be more stable than that produced by bilirubin; in general, it can remain unchanged for about 1 h at room temperature and exposure to air. This overcomes the instability of bilirubin for its direct assay to a certain extent. If a small amount of EDTA is added to the solution, the stability of the wave can be further improved. In addition, the characteristics of the wave have been investigated and it has been confirmed to be an adsorptive catalytic wave. The chemical reaction mechanism is discussed and the green product is confirmed to be biliverdin. 相似文献
913.
The general scheme of the generalized Wronskian technique ms given and is applied tofour energy-dependent potential's eigenvalue problems to generate four classes of nonlinearevolution equations solvable by the inverse spectral transform. 相似文献
914.
本文对蘑菇培养料中分离获得的霉菌、放线菌和细菌进行鉴定和对其生理、生化特性进行测定,对某些菌株在蘑菇生长过程中的作用及作用规律也作了研究.通过研究,初步认为在放线菌和霉菌中有数株菌株对蘑菇的生长有直接或间接的促进作用 相似文献
915.
Li Fa-Shen Yue De-Sheng Zeng Hua-Xin Liu Xin-Fen Yang Zheng 《Hyperfine Interactions》1988,41(1):525-528
MFe2(C2O4)3*6H2O (M=Ni, Zn) powders were prepared by oxalate coprecipitation. Using Mössbauer spectroscopy, XRD, DTA and TEM, the thermal decomposition of MFe2(C2O4)3*6H2O and the formation process of NiFe2O4 and ZnFe2O4 were investigated. 相似文献
916.
Tian Sheng MEI Li Zeng PENG Tao ZHANG Yu Lin LINational Laboratory of Applied Organic Chemistry Institute of Organic Chemistry Lanzhou University Lanzhou 《中国化学快报》2004,15(7)
A concise and stereoselective synthesis of cathasterone's side chain using methyl isopropyl ketone 3 as the fragment is described. 相似文献
917.
C W Turner F G Zeng E M Relkin A R Horwitz 《The Journal of the Acoustical Society of America》1992,92(6):3102-3108
Frequency difference limens for pure tones preceded by a forward masker or followed by a backward masker were obtained across a wide range of signal levels. Relkin and Doucet [Hear. Res. 55, 215-222 (1991)] have shown that at a masker-signal delay of 100 ms, the thresholds of high-SR (spontaneous rate) auditory-nerve fibers are recovered, while the low-SR fiber thresholds are not. Therefore, forward-masked frequency discrimination potentially offers a method to investigate the role of low-SR fibers in the coding of frequency. It has been shown that when an intense forward masker is presented 100 ms before a pure-tone signal, intensity difference limens are elevated for mid-level signals [Zeng et al., Hear. Res. 55, 223-230 (1991)]. However, Plack and Viemeister [J. Acoust. Soc. Am. 92, 3097-3101 (1992)] have shown that a similar elevation in the intensity difference limen is obtained under conditions of backward masking, where selective adaptation of the auditory neurons would not be expected to occur. A condition of backward-masked frequency discrimination was therefore included to investigate the role of interference resulting from adding additional stimuli to a discrimination task. For signals at 1000 and 6000 Hz, there was no effect of a forward masker upon frequency difference limens. For the backward-masked conditions, an elevation of the frequency difference limen was observed at all signal levels, demonstrating that the effects of forward and backward maskers upon frequency discrimination are dissimilar and suggesting that cognitive effects are present in backward-masked discrimination tasks.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
918.
The exchange of electrons between adjacent ions in different oxidation states in vonsenite was observed using Mössbauer spectroscopy. The Mössbauer spectra of a series of naturally occurring vonsenite were recorded over a temperature range of 120–773 K. Four quadrupole doublets were resolved by computer fitting and assigned to Fe2+(Fel), Fe2+(Fe3), Fe3+(Fe2, Fe4) and Fe2+-Fe3+(Fe2–Fe4). The percentage of iron sites participating in an electron exchange process increases from 17% between 120 and 298 K to 27% between 573 and 773 K. 相似文献
919.
920.
High repetition rate pulsed laser of twin wavelengths from KTiOPO4 optical parametric oscillation 总被引:1,自引:0,他引:1 下载免费PDF全文
In this paper, some key techniques of KTiOPO_4 optical parametric oscillation (OPO) laser with repetitive frequencies and twin wavelengths output have been analysed theoretically and studied experimentally in detail. An intracavity optical parametric oscillator (IOPO) has been applied. Operating under 20Hz, laser output energy of more than 38mJ with twin wavelengths 1.57μm and 1.06μm has been achieved. Results of the experiments agree well with the theoretical discussion. 相似文献