Using solid phase reaction method,the perovskite Pr(0.64)Ag(0.044)MnAl(0.2)O3 with super magnetoresistance is prepared. By analyzing its structure and components,it is found that integral perovskite structure can be formed only when the sintering temperature is higher than 1 100 ℃,the structure is cubic with its lattice constant of about 0.386 nm.
Basing on the permeating power of helium through glass, we have derived the dynamic equation for the pressure of He in a He-Cd laser and the replenishing equations for replenisher of He at constant temperature and constant quantity.
These allow natural representations of constant and, sometimes, linear components.
例句来源
We study nonlinear dispersive systems of the form where k=1, …, n, j ∈ ?+, and Pk(·) are polynomials having no constant or linear terms.
例句来源
We show that if(X,Σ, μ) is not purely atomic, then the unconditional basis constant of our basis is (max(p, q) -1).
例句来源
The first result is an enhancement of the Paley-Wiener type constant for nonharmonic series given by Duffin and Schaefer in [6] and used recently in some applications (see [3]).
例句来源
We show how to reconstruct functions satisfying the scaling equations above and show that ?2, …, ?q always constitute a tight frame with constant 1.
The absorption wavemeter investigated consists of a single loop with a variable gap which is formed by a pair of parallel plates. A calibration formula for the meter was derived on the assumption that the stray capacity could be considered constant and the stray inductance negligible. This simple and useful formula was ex perimentally checked on four different meters, covering the range from about one-and-quarter meter to one-half meter. These melors were carefully constructed and accurately calibrate...
The dielectrie constants of toluene, carbon bisulphide, normal pentane, normal hexane, ethyl ether and iso-amyl alcohol were measured by a capacity bridge using a specially constructed liquid condenser at both 30° and 75℃ (22.4℃ only for the last liquid), for frequencies of 600,1000 and 2000 cycles per sec. and under pressures from 1 up to 12,000 kg/cm2. For the first four liquids, the dielectric constant is practically independent of the frequencies
Self-recording system is devised and used to measure potential gradient at Yenching. In fine weather the results show two maxima and two minima for a whole day. During raining potential gradient is constant at zero value, except when lightening and thunderstorm occur in which case the potential gradient changes rapidly both in magnitude and direction.