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951.
A temperature-transient method to estimatein situ formation thermal conductivity and equilibrium formation temperature using circulation fluid flow-rate pulses is described. Flow-rate changes induce temperature variations in the well and the time from when the flow alters to the subsequent maximum or minimum temperature of the drilling fluid can be used to determine these two formation parameters. Some examples are presented to illustrate the method. 相似文献
952.
Darrell F. Strobel 《Pure and Applied Geophysics》1989,130(2-3):533-546
A review of the important constraints on gravity wave induced diffusion of chemical tracers, heat, and momentum is given. Ground-based microwave spectroscopy measurements of H2O and CO and rocket-based mass spectrometer measurements of Ar constrain the eddy diffusion coefficient for constituent transport (K
zz
) to be (1–3)×105 cm2s–1 in the upper mesosphere. Atomic oxygen data also limitsK
zz
to a comparable value at the mesopause. From the energy balance of the upper mesosphere the eddy diffusion coefficient for heat transport (D
H
) is, at most 6×105 cm2s–1 at the mesopause and decreasing substantially with decreasing altitude. The available evidence for mean wind deceleration and the corresponding eddy diffusion coefficient for momentum stresses (D
M
) suggests that it is at least 1×106 cm2s–1, in the upper mesosphere. Consequently the eddy Prandtl number for macroscopic scale lengths is >3. 相似文献
953.
954.
An analysis of the meteorological data collected by the research vessel ORV Sagarkanya for the mean latent and sensible heat
fluxes over the Arabian Sea has indicated appreciable changes between active and weak phases of the southwest monsoon of 1986.
We suggest that: (a) the presence of a core of low level winds associated with the Somali jet and its southward shift during
the season, along with (b) a ridge in surface pressure over the central Arabian Sea could be responsible for the deficit in
monsoon rainfall along the west coast of India in 1986. 相似文献
955.
956.
Over the past 20 years the study ofP- andS-wave velocities in the upper mantle of the Mediterranean area and continental Europe has been the subject of intensive research work. We present a summary of results based on the inversion of available surface-wave dispersion data andP-wave trave time observations. For areas characterized by different tectonic settings and very large lateral variations, a discussion is made about structural models based on seismological, geothermal and electrical conductivity data. 相似文献
958.
热泵在多年冻土地区工程中的应用 总被引:1,自引:1,他引:1
Sergei Guly 《冰川冻土》2004,26(Z1):220-226
The inclement climate and permafrost have a strong influence on human activities and life in cold regions. It is important to adjust to these conditions in such a way as to minimize adverse environmental impacts. In order to maintain the ecological equilibrium, various technologies have been developed which involve the use of the natural cold for solving difficult engineering problems. Heat pumps hold much promise in this context. They can help protect the environment from the thermal effects of human activities and, unlike the conventional refrigeration devices; the produced heat can be utilized. They also provide a solution to another problem vitally important for the northern regions - saving of fuel and energy resources. In case of global warming with an increasing need for artificial refrigeration, the use of heat pumps will be the most economical solution, preventing catastrophic loss of structural stability virtually without additional costs. 相似文献
959.
960.