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1.
Trent D Lund Timothy W West Lilyan Y Tian Lihong H Bu Daniel L Simmons Kenneth DR Setchell Herman Adlercreutz Edwin D Lephart 《BMC neuroscience》2001,2(1):20-13
Background
In learning and memory tasks, requiring visual spatial memory (VSM), males exhibit superior performance to females (a difference attributed to the hormonal influence of estrogen). This study examined the influence of phytoestrogens (estrogen-like plant compounds) on VSM, utilizing radial arm-maze methods to examine varying aspects of memory. Additionally, brain phytoestrogen, calbindin (CALB), and cyclooxygenase-2 (COX-2) levels were determined. 相似文献2.
M. Tamura J. Luque J.E. Harrington P.A. Berg G.P. Smith J.B. Jeffries D.R. Crosley 《Applied physics. B, Lasers and optics》1998,66(4):503-510
Received: 10 June 1997/Revised version: 25 November 1997 相似文献
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J. Luque J.B. Jeffries G.P. Smith D.R. Crosley 《Applied physics. B, Lasers and optics》2001,73(7):731-738
The combination of two-dimensional, planar laser-induced fluorescence (PLIF) and cavity ring-down (CRD) absorption spectroscopy
is applied to map quantitatively the spatial distributions of CH2O and CH in a methane/air flame at 25 Torr. Both species are detected in the same spectral region using the overlapping CH2O A 1
A
2
-X
1
A
1
41
0 and CH B-X(1,0 )bands. The combination of diagnostic techniques exploits the spatial resolution of LIF and the quantitative
CRD absorption measure of column density. The spatially resolved PLIF provides the distribution of absorbers and line-of-sight
CRD absorption the absolute number density needed for quantitative concentration images. The peak CH2O concentration is (3.5±1.4 )×1014 cm-3, or 1450±550 ppm at 1000 K. The lack of precise absorption cross-section data produces these large error limits. Although
a flame model predicts lower amounts, these large uncertainties limit this measurement’susefulness as a test of the flame
chemistry.
Received: 24 April 2001 / Revised version: 10 July 2001 / Published online: 10 October 2001 相似文献
5.
Absolute CH concentrations in low-pressure flames measured with laser-induced fluorescence 总被引:1,自引:0,他引:1
Laser-induced fluorescence in both theA–X andB–X band systems was used to measure absolute number densities of CH radicals in 40 Torr propane/air flames at temperatures near 1600 K. The fluorescence signal was calibrated against Rayleigh scattering in N2 and Raman scattering in H2. In a rich flame, = 1.15, the concentration at the peak of the CH distribution was 5.8 ± 1.5 ppm, or (1.4 ± 0.4) × 1012 cm–3, with independent values obtained using both band systems and calibration methods in good agreement. This result compares well with a prediction of 8 ppm from a kinetic model of this flame. 相似文献
6.
State-to-state rotational energy transfer (RET) rate coefficients for NO (A 2Sigma+, v'=0, J=5.5, 11.5, 17.5) were measured for N2 and O2 at room temperature using a pump-probe method. The NO A 2Sigma+ state is prepared by 226 nm light and the RET is monitored by fluorescence from the D 2Sigma+ v'=0 state, following excitation by a time-delayed laser at approximately 1.1 microm. Additionally, total collisional removal and final state distributions were measured exciting in the Q1+P21 band head, to simulate an NO laser-induced fluorescence atmospheric monitoring scheme. Time-resolved modeling is used to understand relaxation mechanisms and predict relaxation times in ambient air. H2O at atmospherically relevant concentrations does not affect the degree of RET in ambient air. 相似文献
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Ş. Yalçin D.R. Crosley G.P. Smith G.W. Faris 《Applied physics. B, Lasers and optics》1999,68(1):121-130
Received: 17 June 1998/Revised version: 17 September 1998 相似文献
9.
A. Brockhinke A.T. Hartlieb K. Kohse-Höinghaus D.R. Crosley 《Applied physics. B, Lasers and optics》1998,67(5):659-665
2 in a flame, excited by a tunable KrF laser near 248 nm. The first comprises several P and R lines of the (1,0) band of the
e 3Πg-a 3Πu Fox–Herzberg system, with fluorescence bands extending past 350 nm. The second is the band head region of the (7,1) band
of the D 1Σu
+←B′ 1Σg
+ system, with fluorescence at 232 nm from D to the X 1Σg
+ ground state. Neither band has been previously observed in any environment. The flame in these experiments is highly sooting,
and the C2 seen here is likely produced by laser vaporization of the soot with subsequent laser photolysis of a C2 precursor. In a rich flame, this fluorescence could cause interferences in other studies such as KrF laser Raman scattering.
Moreover, signal level calculations suggest native C2 near 10 ppm could be readily observed using the Fox–Herzberg excitation. Raman measurements of major species (X≥0.01) in
the same flame, using the KrF laser, are in good agreement with a model prediction.
Received: 2 April 1998/Revised version: 8 June 1998 相似文献
10.
DR.G. Domairry A. Mohsenzadeh M. Famouri 《Communications in Nonlinear Science & Numerical Simulation》2009,14(1):85-95
In this paper Jeffery–Hamel flow has been studied and its nonlinear ordinary differential equation has been solved through homotopy analysis method (HAM). The obtained solution in comparison with the numerical ones represents a remarkable accuracy. The results also indicate that HAM can provide us with a convenient way to control and adjust the convergence region. 相似文献