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1.
Summary To clarify the ionization equilibrium near the ground, simultaneous measurements of the rate of ion pair production (q), the concentrations of small ions (n) and condensation nuclei (Z), and the diffusion coefficient of condensation nuclei (D) were carried out at several stations in the central area of Japan. The total rate of ion pair production (q) was estimated fromq=q(Rn)+q(Tn)+q()+q(+CR). The value ofq was estimated as 10J to 20J. The mean life () and the effective attachment coefficient () of small ions were also estimated at each station. Correlations amongn, Z, q, andD were also studied. If we take the variation ofD into consideration, the correlation was expressed by the simple formula;q=n Z. The dependence of upon size of nuclei (2r) were also measured, and was found to correlate well withD orr. 相似文献
2.
Summary The stress sensitivitiesS
x andS
R of susceptibility and remanence for titanomagnetite-bearing rocks are calculated in terms of magnetostriction constants
100 and
111 and anisotropy constantsK
1,K
2 of the magnetic minerals.S
x andS
R are represented by quite different algebraic expressions but happen to have comparable numerical values over the whole range of titanomagnetite compositions. Both increase strongly with titanium content. This leads to more optimistic calculations of tectonomagnetic effects than with the previously assumed stress sensitivity for pure magnetite. 相似文献
3.
To obtain the temperatureT and volumeV (or pressureP) dependence of the Anderson-Grüneisen parameter
T
, measurements with high sensitivity are required. We show two examples:P, V, T measurements of NaCl done with the piston cylinder and elasticity measurements of MgO using a resonance method. In both cases, the sensitivity of the measurements leads to results that provide information about
T
(,T), where V/V
0 andV
0 is the volume at zero pressure. We demonstrate that determination of
T
leads to understanding of the volume and temperature dependence ofq=( ln / lnV)
T
over a broadV, T range, where is the Grüneisen ratio. 相似文献
4.
Summary In order to evaluate the accuracy of measurements repeated by a set of gravimeters the semi-systematic errors
2
and
3
were introduced besides the random error
1
in[1]. It is shown that Eqs.(10) and(11), given in[1], should not be used to determine these errors, but Eqs.(8) and(9). 相似文献
5.
Lunar and solar atmospheric tidal oscillations have been determined with reasonable accuracy from a ten-year record of hourly mercury-barometer readings, corrected to mean-sea-level, at Rarotonga (Cook Islands), 21.2°S. For the lunar semidiurnal tide, the annual determination shows an amplitude (56 b) slightly lower and a phase (51°) much smaller than the values (58 b, 72°) that would be derived, for the position of Rarotonga, from the spherical harmonic analysis given byHaurwitz andCowley (1969). The seasonal variation of this oscillation, as given by the monthly and J, E, D values, shows most of the characteristic features found in world-wide determinations. In particular, the near equality of the J, D amplitudes at Rarotonga tends to support theHaurwitz andCowley (1969) suggestion of negative J-D values in southern middle latitudes. For the solar tides, the semidiurnal and terdiurnal oscillations at Rarotonga are similar to those found at other stations in the south-west Pacific region. However, for the diurnal oscillation, the annual amplitude (232 b) is only about half the value (465 b) indicated for the position of Rarotonga by the world maps of theS
1(p) annual harmonic coefficients given byHaurwitz (1965). It thus seems likely that the relatively small area of lowS
1(p) annual amplitude in the eastern part of the south Pacific, as indicated by these maps, is much more extensive than formerly supposed. 相似文献
6.
This work is part of an attempt to quantify the relationship between the permeability tensor (K) and the micro-structure of natural porous media. A brief account is first provided of popular theories used to relate the micro-structure toK. Reasons for the lack of predictive power and restricted generality of current models are discussed. An alternative is an empirically based implicit model whereinK is expressed as a consequence of a few pore-types arising from the dynamics of depositional processes. The analytical form of that implicit model arises from evidence of universal association between pore-type and throat size in sandstones and carbonates. An explicit model, relying on the local change of scale technique is then addressed. That explicit model allows, from knowledge of the three-dimensional micro-geometry to calculateK explicitly without having recourse to any constitutive assumptions. The predictive and general character of the explicit model is underlined. The relevance of the change of scale technique is recalled to be contingent on the availability of rock-like three-dimensional synthetic media. A random stationary ergodic process is developed, that allows us to generate three-dimensional synthetic media from a two-dimensional autocorrelation functionr(
x
,
y
) and associated probability density function
measured on a single binary image. The focus of this work is to ensure the rock-like character of those synthetic media. This is done first through a direct approach:n two-dimensional synthetic media, derived from single set (
,r(
x
,
y
)) yieldn permeability tensorsK
i-1,n
i
(calculated by the local change of scale) of the same order. This is a necessary condition to ensure thatr(
x
,
y
) and
carry all structural information relevant toK. The limits of this direct approach, in terms of required Central Process Unit time and Memory is underlined, raising the need for an alternative. This is done by comparing the pore-type content of a sandstone sample andn synthetic media derived fromr(
x
,
y
) and
measured on that sandstone-sample. Achievement of a good match ensures that the synthetic media comprise the fundamental structural level of all natural sandstones, that is a domainal structure of well-packed clusters of grains bounded by loose-packed pores. 相似文献
7.
Georgi T. Nestorov 《Pure and Applied Geophysics》1965,62(1):148-160
Zusammenfassung Es wird die Gleichung für die Elektronenproduktionq(z) abgeleitet, die die meteorologischen Elemente der Mesosphäre berücksichtigt. Nach Angaben über die mit Satelliten und Raketen gemessene Röntgenstrahlung mit 8 Å wird das Differentialspektrum des ionisierenden Energieflusses für eine mittlere Sonnenaktivität konstruiert. Auf dieser Grundlage und nach der bekannten Intensität der Strahlung Ly- sowie nach Angaben über dieElektronenproduktion der kosmischen Strahlung werden die Profileq
Rö(z),q
Ly-(z) undq
CR(z) für mittlere geographische Breiten und Standardatmosphäre entwickelt. Nach eingehender Analyse der vollständigen Gleichung für den effektiven Rekombinationskoeffizienten wird für die Verhältnisse in der tiefen Ionosphäre der Beitrag jeder einzelnen Komponente der Gleichung bestimmt. ist eine recht veränderliche Grösse, die von den aeronomischen und meteorologischen Verhältnissen und der Sonnenzenitdistanz abhängt. Aus den fürq(z) und (z) erhaltenen Angaben werden zwei ElektronendichteprofileN(z) für =30° und 75° erhalten. Das ProfilN(z) bei =30° wird mit dem gemittelten Profil einer umfangreichen Gruppe experimentell gefundener VerteilungenN(z) verglichen; das Profil bei =75° wird durch Messung der deviativen und nondeviativen Absorption für eine längere Zeitperiode überprüft. In beiden Fällen hat sich die Richtigkeit der theoretisch erhaltenen Profile bestätigt. Die jahreszeitlichen Variationen der nondeviativen Absorption in derD-Region sind ausschliesslich durch die Variationen der meteorologischen Parameter im Bereich der Mesopause bei konstantem Energiefluss der ionisierenden Strahlung bedingt.
Summary An equation about the electron production is deduced in which the meteorological elements of the mesosphere are taken into account. The differential spectrum of the ionizing energy flux with 3 Å for average solar activity is constructed on evidence from rocket and satelitc measurements. The profilesq Rö(z),q Ly-(z) andq CR(z) for mean geographical latitudes and standard atmosphere are plotted on that basis as well as on data fot the known intensity of the Ly- emission and the electron production of the cosmic rays. An exhaustive analysis is made of the full equation for the effective recombination coefficient and the contribution of all its components at lower ionosphere conditions is determined. is a rather variable quantity, dependent on the aeronomical and meteorological condition of the area under consideration, as well as on the solar zenith angle. Two profiles for the electron concentrationN(z) at =30° and 75° are drawn on the basis of data forq(z) and (z). The profileN(z) at =30° is compared with the averaged profile of a large group experimentally obtained distributionsN(z); the profile at =75° is checked by measurements of the deviative and nondeviative absorption taken for a lengthy period. Both checks are in good agreement with the theoretically obtained profiles. The seasonal variations of the nondeviative absorption in theD region could be completely explained with the variations of the meteorological parameters in the mesopause area at constant energy flux of the ionizing radiation.相似文献
8.
Prakash Chandra Singh 《Pure and Applied Geophysics》1972,98(1):87-101
Summary Dispersion in Rayleigh waves is discussed for semi-infinite media with =
1(1 ± cos s z) and =
1(1 ± cosh s z), being the rigidity of the medium. A few workers tried with the above Fourier type of model but failed to find the dispersive nature. Because they neglected s due to the complexity of the calculation they arrived at a non dispersive frequency equation. This difficulty is removed in this paper and a dispersive frequency equation is obtained which shows both direct and inverse dispersion. The second model leads to non-convergent solution forz but shows many interesting results which are also discussed. 相似文献
9.
Summary This paper studies the propagation of Surface Waves on a spherically aeolotropic shell surrounded by vacuum. The elastic constantsc
ij and density of the material of the shell are assumed to be of the form
ij
r
l and
o
r
m respectively, where
ij
o are constants andl, m are any integers. 相似文献
10.
The World Ocean Atlas 1998 is used to determine the global field of the meridional density ratio R
hy
=T/S, where temperature and salinity changes T and S are evaluated along meridians, in and below the mixed layer. The focus of the analysis is the identification of regions where the R
hy
field matches the values R
=2 sometimes suggested as the commonly perceived state of the ocean and R
=1, the condition of density compensation. Results are presented through fields of the meridional Turner angle Tu
hy
=arctan(R
hy
) and through histograms of Tu
hy
for the Pacific, Atlantic and Indian Oceans at the ocean surface and at 300 m depth. At the 300-m depth level, which in the subtropics is representative of conditions in the permanent thermocline, the most frequently encountered values of the meridional density ratio are R
hy
=3.2 in the North and South Pacific, R
hy
=2.0 in the South Atlantic and Indian and R
hy
=1.6 in the North Atlantic Ocean. Conditions in the mixed layer are more variable and show seasonal differences, but R
hy
=2.0 occurs prominently in all ocean regions during winter and in all regions but the Atlantic during summer. Summer values for the Atlantic Ocean are R
hy
=3.2 in the Northern Hemisphere and R
hy
=2.4 in the Southern Hemisphere. Detailed analysis of R
hy
across the Subtropical Front (STF) confirms the most frequently observed values but shows zonal variation along the front in some oceans. Nearly complete density compensation (R
hy
=1) in the mixed layer is encountered in the STF of the eastern North Pacific, the eastern South Pacific and the eastern Indian Ocean. The eastern Indian Ocean south of Australia is also the only region where complete density compensation in the STF occurs below the mixed layer.Responsible Editor: Neville Smith
AcknowledgementWe thank Dan Rudnick for helpful comments and discussion during the preparation of this paper. 相似文献
11.
New equations and techniques for dealing with drop breakups are developed and applied to the modelling of the evolution of raindrop spectra in rainshafts. Breakup experiments byMcTaggart-Cowan andList (1975) served as data base.No matter what the original size distribution, the spectrum evolution will always lead to a Marshall-Palmer type equilibrium di tributionN=N
0e–D, with =constant andN
0 proportional to the rainfall rateR. (D stands for raindrop diameter.) ForR29 mm h–1 and an original Marshall-Palmer distribution, the required fall height to reach equilibrium is 2 km.The equilibrium distributions are characterized by linear relationships betweenR, the radar reflectivity factorZ, the liquid water content LWC and theN
0 of the Marshall-Palmer distribution. Possible explanations for the discrepancy with observations are given.The fact that the all-water processes cannot produce drops withD2.5 mm (as confirmed by observations) leads to the conclusion that observed large raindrops withD5 mm represent melted hailstones and have not yet reached an equilibrium distribution. These latter conclusions were reached within the original assumption of videspread, steady state precipitation. 相似文献
12.
Radan Huth 《Studia Geophysica et Geodaetica》1992,36(3):280-292
Summary One of the important atmospheric levels, the mean energetic level (MEL), which in a sense reflects the energetics of the whole atmosphere, is defined. Its fundamental properties are shown. In order to describe the MEL correctly a new vertical coordinate is introduced and discussed. The new coordinate, , is defined as the ratio of height and temperature. The MEL is shown to be a level with constant value of . Some incorrect conclusions concerning the MEL, derived in the past, have been corrected.List of symbols used
c
p
specific heat of air at constant pressure
-
c
v
specific heat of air at constant volume
-
e
base of natural logarithms
-
E
total potential energy
-
f
Coriolis parameter
-
g
acceleration of gravity
-
i
specific internal energy
-
I
internal energy
-
J
enthalpy
-
k
unit vector pointing upwards
-
p
pressure
-
Q
diabatic heating rate
-
R
gas constant of the air
-
t
time
-
T
temperature
-
v
horizontal velocity
-
v
(3)
three-dimensional velocity
-
w
vertical velocity in thez-system
-
z
height
-
temperature growth rate (T/z)
-
Pechala's vertical coordinate (z/T)
-
generalized vertical velocity in the -system (d/dt)
-
specific potential energy
-
potential energy
-
density of the air
-
Ruppert function
-
T(1–)–1
- ( )
S
quantity at the sea level
- ( )*
quantity at the MEL 相似文献
13.
Khairi I. Grais 《Pure and Applied Geophysics》1969,74(1):78-82
Summary The darkening (S) of Illford Q2 photographic plates as ion detectors in mass spectrometer has been investigated. The dependence of the darkening (S) on the ion density (n=ions/mm2) i.e.S=S(n)E for constant energy (E)=z U ranging from 4U20 Kv of the impinging40A+1-,40A+2- and40A+3-ions whenS does not exceed the value 0.15 and the second relationn=n(z U)
S
for darkening 0.05S0.15 constructed from the above relationS=S(n)
E
has been determined. The darkening was found to increase with increasing ion-density which inturn decreases with the ionenergy. For40A+1-,40A+2-, and40A+3-ion of equal energy and ion-density the darkening effect was independent of the number of the charges carried by the argon ion. 相似文献
14.
We estimate (/T)
P
of the lower mantle at seismic frequencies using two distinct approaches by combining ambient laboratory measurements on lower mantle minerals with seismic data. In the first approach, an upper bound is estimated for |(/T)
P
| by comparing the shear modulus () profile of PREM with laboratory room-temperature data of extrapolated to high pressures. The second approach employs a seismic tomography constraint ( lnV
S
/ lnV
P
)
P
=1.8–2, which directly relates (/T)
P
with (K
S
/T)
P
. An average (K
S
/T)
P
can be obtained by comparing the well-established room-temperature compression data for lower mantle minerals with theK
S
profile of PREM along several possible adiabats. Both (K
S
/T) and (/T) depend on silicon content [or (Mg+Fe)/Sil of the model. For various compositions, the two approaches predict rather distinct (/T)
P
vs. (K
S
/T)
P
curves, which intersect at a composition similar to pyrolite with (/T)
P
=–0.02 to –0.035 and (K
S
/T)
P
=–0.015 to –0.020 GPa/K. The pure perovskite model, on the other hand, yields grossly inconsistent results using the two approaches. We conclude that both vertical and lateral variations in seismic velocities are consistent with variation due to pressure, temperature, and phase transformations of a uniform composition. Additional physical properties of a pyrolite lower mantle are further predicted. Lateral temperature variations are predicted to be about 100–250 K, and the ratio of ( lnp/ lnV
S
)
P
around 0.13 and 0.26. All of these parameters increase slightly with depth if the ratio of ( lnV
S
/ lnV
P
)
P
remains constant throughout the lower mantle. These predicted values are in excellent agreement with geodynamic analyses, in which the ratios ( ln / lnV
S
)
P
and ( / lnV
S
)
P
are free parameters arbitrarily adjusted to fit the tomography and geoid data. 相似文献
15.
T. L. Chelidze H. Spetzler I. C. Getting Z. A. Avaliani 《Pure and Applied Geophysics》1990,134(1):31-43
The elastic properties of a physical model representing a damaged rock matrix were studied using a square lattice deformed under tensile stress. The elastic modulusM of such a system varies in agreement with percolation theory as|x–x
c
|
f
, wherex is the damage parameter andx
c
the threshold value of the damage parameter,f3.6. Atxx
c
the scale dependence ofM can be expressed asML
–f/v
, whereL is the size of the sample andv the correlation exponent in percolation theory.The experimental results are of interest in assessing elastic properties in earthquake focal zones and fault zones in general. 相似文献
16.
Ignacio G. Galindo 《Pure and Applied Geophysics》1965,60(1):189-196
Summary Measuring, with the aid of two filters, the instantaneous intensity of the solar radiation in two wave lengths (
B
= 0.44 ,
R
= 0.64 ) by means of a sun photometer designed byVolz, we carried out determinations of the decadic turbidity coefficientB (=0.5 ) and the wave length exponent of the haze extinction for Mexico City. Observations were made for almost two and a half years (1960 to 1962 period). A seasonal size distribution in both parameters was found. Although the data thus obtained are provenient of a contaminated atmosphere, comparison of our data is made with those found for higher latitudes ofÅngström, Schüepp andVolz. The height of the homogeneous haze layerH
D
was calculated showing pronounced variations for a given wind direction. The maximum and minimum values ofB enable us to get, by the first approximation, the aerosol size distribution ofJunge for our latitudes. However, for exceptional very clear days having maximum actinometric intensity of the solar radiation the sensitivity of the microamperimeter in theVolz sun photometer fails. 相似文献
17.
Summary The principle of the sampling method of submicron aerosols with the Aerosol Spectrometer is briefly described and the analytic procedures for deriving the frequency-size distributionC
d
(d) from photo-micrographic particle counts and microphotometric light scattering measurementsS
d
(d) of identical areas of the particle deposit.After initial analysis the deposits were exposed to elevated temperature (80° C) for several hours and re-analyzed. Four representative aerosol types, originating from the high sea, the shore, vegetation, and metropolitan smog are analyzed in this manner for the range (0.2 d1.3 ). All show a very marked decrease, even disappearance of the smaller particles (d<0.5 ) and shrinkage of the larger particles (d<1 ). By far the largest effect is observed for the smog aerosols.This volatility appears to be caused by either evaporation of the particle substace or by the gradual oxidation of its organic components into more volatile products (CO2, H2O). 相似文献
18.
M. Poddar 《Pure and Applied Geophysics》1981,119(5):1024-1036
FollowingDmitriev (1960) a rigorous theoretical solution for the problem of scattering by a perfectly conducting inclined half-plane buried in a uniform conductive half-space has been obtained for plane wave excitation. The resultant integral equation for the Laplace transform of scattering current in the half-plane is solved numerically by the method of successive approximation. The scattered fields at the surface of the half-space are found by integrating the half-space Green's function over the transform of the scattering current.The effects of depth of burial and inclination, of the half-plane on the scattered fields are studied in detail. An increase in the depth of burial leads to attenuation of the fields. Inclination introduces asymmetry in the field profiles beside affecting its magnitude. Depth of exploration is greater for quadrature component. An interpretation scheme based on a phasor diagram is presented for the VLF-EM method of exploration for rich vein deposits in a conductive terrain.List of symbols
x, y, z
Space co-ordinates
-
Half-space conductivity
- 0
Free-space permeability
-
Excitation frequency (angular)
-
T
Time
-
h
Depth of the half-plane
-
a
Inclination of the half-plane
-
E
x
x-Directed total electric field
-
E
x
p
x-Directed primary electric field
-
E
xo
p
x-Directed primary electric field atz=0 directly over the half-plane
-
H
y
y-Component of total magnetic field
-
H
y
p
y-Component of primary magnetic field
-
H
y0
p
y-Component of primary magnetic field atz=0 directly over the half-plane
-
H
z
z-Component of total magnetic field
-
H
z
p
z-Component of primary magnetic field
-
J
x
Surface density ofx-directed scattering current
-
G
Green's function
-
k
0,K
Wave numbers
-
u,u
0,u
1,u
2
Functions
-
Space co-ordinate
-
s
Variable in transform domain
-
Variable of integration
-
Normalized scattering current
-
Laplace transform of
-
N
Normalized
- , 0, 1, 2
Functions
-
t
Variable of integration
-
Skin depth
-
H
Total magnetic field
-
H
p
Primary magnetic field
-
H
0
p
Primary magnetic field atz=0 directly over the half-plane
-
M,Q,R,S,U,V
Functions
-
N
1,N
2
Functions 相似文献
19.
Ronald L. Drake 《Pure and Applied Geophysics》1972,94(1):248-259
Summary This paper considers an incompressible fluid flowing through a straight, circular tube whose walls are uniformly porous. The flow is steady and one dimensional. The loss of fluid through the wall is proportional to the mean static pressure in the tube. Several formulations of the wall shear stress are considered; these formulations were motivated by the results from Hamel's radial flow problem, boundary layer flows/and boundary layer suction profiles. For each of these formulations exact solutions for the mean axial velocity and the mean static pressure of the fluid are obtained. Sample results are plotted on graphs. For the constant wall shear stress problem, the theoretical solutions compare favorably with some experimental results.Notations
A, B, D, E
constant parameters
-
a, b
constant parameters
-
Ai(z), Bi(z)
Airy functions
-
Ai, Bi
derivatives of Airy functions
-
k
constant of proportionality betweenV andp
-
L
length of pores
-
p,p
mean static pressure
-
p
0
static pressure outside the tube
-
p
0
value ofp atx=0
-
Q
constant exponent
-
R
inside radius of the tube
-
T
wall shear stress
-
T
0
shear parameter
-
t
wall thickness
-
U
free stream velocity
-
,u
mean axial velocity
-
u
0
value ofu atx=0
-
V,V
mean seepage velocity through the wall
-
v
0
mean seepage velocity
-
x,x
axial distance along the tube
-
z
transformed axial distance
-
z
0
value ofz atx=0
-
mean outflow angle through the wall
-
cos
-
density of the fluid
-
wall shear stress
-
dynamic viscosity of the fluid
- over-bar
dimensional terms
- no bar
nondimensional terms
The National Center for Atmospheric Research is sponsored by the National Science Foundation 相似文献
20.
A numerical study has been made of the heat transfer through a fluid layer with recirculating flow. The outer fluid surface was assumed to be spherical, while the inner surface consisted of a sphere concentrically or eccentrically located with respect to the outer spherical surface. The recirculating flow was assumed to be driven by a gas flow creating stress on the fluid's outer surface so that creeping (low Reynolds number) flow developed in its interior. The present study solves the Stokes equation of motion and the convective diffusion equation in bispherical coordinates and presents the streamline and isotherm patterns.Nomenclature
a
i
inner sphere radius
-
a
d
outer sphere radius
-
A
1
defined by equation (5)
-
A
2
defined by equation (6)
-
B
1
defined by equation (7)
-
B
2
defined by equation (8)
-
c
dimensional factor for bispherical coordinates
-
C
constant in equation (4)
-
d
narrowest distance between the two eccentric spheres
-
E
2
operator defined by equation (1) in spherical coordinates and by equation (21) in bispherical coordinates
-
G
modified vorticity, defined in equation (22)
-
G
*
non-dimensional modified vorticity, defined in equation (28)
-
h
metric coefficient of bispherical coordinate system, defined in equation (18)
-
k
w
thermal conductivity of water
-
K
1
defined by equation (9)
-
K
2
defined by equation (10)
-
N
Re
Reynolds number=2a
dU/gn
-
N
Pe,h
Peclet number=2a
dU/
-
n
integer counter
-
q
heat flux
-
r
radius
-
r
*
non-dimensional radius=r/a
d
-
S
surface area
-
t
time
-
t
*
non-dimensional time=t/a
d
2
-
T
temperature
-
T
o
temperature at inner sphere surface
-
T
a
temperature at outer sphere surface
-
T
*
non-dimensional temperature;=(T–T
o)/(Ta–To)
-
u
velocity
-
u
r
radial velocity in spherical coordinates
-
u
angular velocity in spherical coordinates
-
u
radial velocity in bispherical coordinates
-
u
angular velocity in bispherical coordinates
-
U
free stream velocity
-
u
r
*
=u
r/U
-
u
*
=u
/U
-
u
*
=u
/U
-
u
*
=u
/U
Greek symbols a
1
small displacement
-
vorticity, defined in equation (17)
- *
non-dimensional vorticity, defined in equation (27)
-
radial bispherical coordinates
- o
bispherical coordinate of inner sphere
- a
bispherical coordinate of outer sphere
-
angular coordinate in spherical coordinates
-
thermal diffusivity
- w
thermal diffusivity of water
-
kinematic viscosity
-
angular bispherical coordinate
-
spherical coordinate
-
streamfunction
-
non-dimensional streamfunction for spherical coordinates, = /(U
a
d
2
)
- *
non-dimensional streamfunction for bispherical coordinates, defined in equation (26) 相似文献