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31.
使用Gaussian03程序包中的“对称性匹配簇-组态相互作用”方法、在0.13—2.0nm的核间距范围内利用6-311 G(d,p)基组对7Li2(23Πu)分子的势能曲线进行了计算,同时使用最小二乘法将计算结果拟合成了解析势能函数.利用拟合出的解析势能函数并结合Rydberg-Klein-Rees方法,计算了该态的谐振频率,进而计算了该态的其他光谱常数,分别为Te=3.6701eV,De=1.0764eV,Re=0.3000nm,ωe=285.69cm-1,ωeχe=1.8351cm-1,αe=0.00942cm-1和Be=0.5340cm-1,其中光谱常数Te,De,Re和ωe的值与文献值相符很好.以得到的解析势能函数为基础,通过求解双原子分子核运动的径向Schr dinger方程,发现J=0时7Li2(23Πu)分子存在67个振动态,求出了相应于每一振动态的振动能级、振动经典转折点及转动惯量. 相似文献
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Summary Simultaneous Doppler tracking of the same spacecraft from two widely separated stations on the ground can be profitably used
in space experiments for the detection of low-frequency gravitational waves. The second, receiving only station, could be
a VLBI radiotelescope. The instrumentation required to convert a VLBI system to Doppler measurement is relatively easy to
set up and uses a digital tone extractor. The advantages of this new tracking configuration are discussed, espectially in
relation to problem of noise from local sources.
Riassunto L'inseguimento Doppler simultaneo di una sonda interplanetaria da due stazioni di terra può essere usato con vantaggio negli esperimenti spaziali per la rivelazione di onde gravitazionali di bassa frequenza. La seconda stazione, che opererebbe solo in ricezione, può essere un radiotelescopio VLBI. La strumentazione necessaria per convertire un sistema VLBI a misure Doppler è relativamente semplice da sviluppare ed installare, facendo uso di un digital tone extractor. Nel lavoro, si discutono i vantaggi di questa nuova configurazione in relazione al problema dei rumori locali.
Резюме Одновремнное доплеровское рослежнвание космического корабря с помощях наземных станций бытя исполязовано в космических экспериментах по детектированию низкочастотных гравитационных волн. Вторал станция, работающая только в режиме приема, может быть VLBI радиотелескопом. Аппаратура, необходимая для превращения VLBI системы для доплеровских измерений, относительно проста для установки и может быть использовано цифровое устройство для вывода. Обсуждаются преимущества этои новой конфигурации прослеживания особенно в связи с детектированием гравитационного излучения.相似文献
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35.
M. Rezulski 《Optics & Laser Technology》1986,18(2)
Vignetting in the optical system of an electro-optical distance meter is described, and the impact of the measuring conditions is dealt with. The method of analysis, involving numerical calculations, is given and the results for three typical cases are shown. 相似文献
36.
Cilia-induced flow of viscoelastic mucus through an idealized two-dimensional model of the human trachea is presented.The cilia motion is simulated by a metachronal wave pattern which enables the mobilization of highly viscous mucus even at nonzero Reynolds numbers.The viscoelastic mucus is analyzed with the upper convected Maxwell viscoelastic formulation which features a relaxation time and accurately captures normal stress generation in shear flows.The governing equations are transformed from fixed to wave(laboratory)frame with appropriate variables and resulting differential equations are perturbed about wave number.The trachea is treated as an axisymmetric ciliated tube.Radial and axial distributions in axial velocity are calculated via the regular perturbation method and pressure rise is computed with numerical integration using symbolic software MATHEMATICA‘TM’.The influence of selected parameters which is cilia length,and Maxwell viscoelastic material parameter i.e.relaxation time for prescribed values of wave number are visualized graphically.Pressure rise is observed to increase considerably with elevation in both cilia length and relaxation time whereas the axial velocity is markedly decelerated.The simulations provide some insight into viscous-dominated cilia propulsion of rheological mucus and also serve as a benchmark for more advanced modeling. 相似文献
37.
New measurements of the pressure distribution generated by two Newtonian liquids in the Truncated Cone-and-Plate Apparatus are presented, in order to evaluate the exact form of the inertial contribution for a range of Reynolds numbers (Re) fromRe = 140 toRe = 36,000;Re = R
2 /, where and are the liquid density and viscosity respectively,R is the plate radius, and is the angular velocity of the cone. The Walters equation for lowRe, p
w
= 0.15
2 (r2 – R2), is shown to be in excellent agreement with the measurements up toRe = 1000, provided an appropriate correction for the Newtonian hole pressure is made. Up toRe = 1000, the measured slope is within 1% of the theoretical value of 0.15 given by the Walters equation; as the Reynolds number increases above 1000, the data become increasingly nonlinear inr
2. Other theoretical predictions made especially for largeRe begin to disagree with the data even belowRe = 1000. The application of the experimentally determined additive inertial contribution to measurements of pressure distribution in four dilute polymer solutions is found to reproduce adequately the expected form of the viscoelastic pressure distribution, even at highRe where the Walters equation is not valid. Measurements of a combination of normal-stress differencesN
1 + 2N
2 for polymer solutions involving specific polymer/solvent interaction sites show a difference of 45% with change of solvent, while no difference is observed in solutions of polymers without the interaction sites. The normal-stress ratio —N
2/N
1 for a 5% solution of cis-polybutadiene is 0.24 at a shear rate of 100 s–1, and it appears to approach the zero shear limit of 2/7 given by the Doi-Edwards theory. The Higashitani-Pritchard-Baird-Lodge equation relating the elastic hole pressure to the normal-stress differenceN
1 –N
2 gives a qualitative agreement betweenN
1 –N
2 from the TCP Apparatus and the hole pressure from the Stressmeter; the percent difference is 0 at shear stress < 25 Pa, 35% at = 45 Pa, and 18% at the highest = 63 Pa. 相似文献
38.
A new mathematical model is proposed for time-independent laminar flow through a rigid isotropic and consolidated porous medium of spatially varying porosity. The model is based upon volumetric averaging concepts. Explicit assumptions regarding the mean geometric properties of the porous microstructure lead to a relationship between tortuosity and porosity. Microscopic inertial effects are introduced through consideration of flow development within the pores. A momentum transport equation is derived in terms of the fluid properties, the porous medium porosity and a characteristic length of the microstructure. In the limiting cases of porosity unity and zero, the model yields the required Navier-Stokes equation for free flow and no flow in a solid, respectively. 相似文献
39.
APPROXIMATEINERTIALMANIFOLDSFORTHESYSTEMOFTHEJ-JEQUATIONSAPPROXIMATEINERTIALMANIFOLDSFORTHESYSTEMOFTHEJ-JEQUATIONS¥CaiRizeng(... 相似文献
40.