No abstract available

[en] The measured values of the ²¹⁰Pb concentration in the atmospheric deposition in the city of Cienfuegos, Cuba, are presented. A positive relationship is obtained among the concentration of ²¹⁰Pb in the atmospheric deposition and the total annual precipitation (r=0.66, p<0.001). It is suspected that the condition of being an island reduces the potential production ²¹⁰Pb, and therefore the concentration of this radionuclide in the atmospheric fallout

[en] Observations of pulsating auroras in the magnetic zenith and proton and electron auroras along the magnetic meridian were conducted from three stations covering from 58⁰ to 71⁰ invariant during the pulsating aurora campaign in Saskatchewan in January and February of 1980. Pulsations were observed only south of or on the southern edge of the proton precipitation region. This is in general agreement with other uncoordinated studies of proton and pulsating auroras in the late morning hours, but it also appears to be true for isolated events at other times as well. (auth)

No abstract available

[en] Highlights: • The aged Al–0.03Yb–0.06Zr alloy forms core-shell structured Al₃(Yb,Zr) precipitates. • The Al–0.03Yb–0.06Zr alloy obtains a maximum hardness of 485 MPa. • The Al₃(Yb,Zr) precipitates in Al–0.03Yb–0.06Zr have remarkable coarsening resistance. - Abstract: The precipitation hardening and coarsening resistance of precipitates were studied in Al–Yb, Al–Zr and Al–Yb–Zr alloys during aging at 400 °C. The aged Al–0.03Yb–0.06Zr alloy forms core–shell structured Al₃(Yb,Zr) precipitates and the core and shell of precipitates are enriched in Yb and Zr respectively. Due to the dense and core–shell structured Al₃(Yb,Zr) precipitates, the Al–0.03 at%Yb–0.06 at%Zr alloy obtains a maximum hardness of 485 MPa, which is greater than that of the Al–0.03 at%Yb and Al–0.06 at%Zr alloys. The Al₃(Yb,Zr) precipitates in Al–0.03 at%Yb–0.06 at%Zr have remarkable coarsening resistance with a time exponent for the average radius of precipitates 1/n = 0.19 ± 0.02, which is smaller than that for Al–0.03Yb (0.34 ± 0.01)

[en] The relationship of the afternoon/evening diffuse radio aurora, proton and electron precipitation and field-aligned currents is studied with data from the auroral radar at Slope Point, New Zealand, and the ISIS 2 satellite. It is shown that there is a very close association between the radio aurora and (primarily downward) field-aligned currents, which confirms and extends previous work, but that there is no clear relation with either proton or electron precipitation. (author)

[en] Using humidity exchange characteristics (precipitation and vapor) for the river Arafvi basin we have calculated a significant parameter having practical importance, i.e. quantitative response of the flow. This makes possible to conduct extra and interpolation areas of the flow curve and establish flow for any point and height. (author)

[en] Theories for and observations relating to auroral precipitation are reviewed for purposes of assessing our understanding of the aurora and of indentifying those processes which play the most important role in auroral precipitation. For purposes of the review, four categories of auroral forms are defined: (1) the diffuse aurora, which usually forms the equatorward boundary of the auroral oval, (2) auroral patches and pulsations, which appear most commonly within the morning sector of the diffuse aurora, (3) the discrete aurora, most prominently observed in the evening and poleward sectors of the auroral oval, and (4) the 'inverted-V' aurora, which appears in the same regions as discrete aurora but with much larger size scales. One principal conclusion is that the diffuse arora, likely caused by both proton and electron precipitation, is the result of pitch angle scattering by electrostatic cyclotron waves. Another is that the auroral pulsations and patches are the result of pitch angle scattering of more energetic electrons by electromagnetic whistler mode waves. The patches may represent flux tubes of enhanced ionization tied to the lower ionosphere. The discrete aurora is the result of electron acceleration parallel to the magnetic field by the quasi-static electric field of a current-driven laminar electrostatic V shock. The theory for inverted-V precipitation is not well developed, but observations strongly suggest that it is related to ion cryclotron anomalous resistivity

[en] A summary of recent positron annihilation work on Russian VVER type reactor steels is presented. Thereby, special attention is paid to the outline of basic processes that might help to understand the positron behaviour in this class of industrial material. The idea of positron trapping by irradiation-induced precipitates, which are probably carbides, is discussed in detail. (orig.)

[en] A new concept in particulate control, called an advanced hybrid particulate collector (AHPC), is being developed under funding from the U.S. Department of Energy. The AHPC combines the best features of electrostatic precipitators (ESPs) and baghouses in a manner that has not been done before. The AHPC concept consists of a combination of fabric filtration and electrostatic precipitation in the same housing, providing major synergism between the two collection methods, both in the particulate collection step and in transfer of the dust to the hopper. The AHPC provides ultrahigh collection efficiency, overcoming the problem of excessive fine-particle emission with conventional ESPs, and it solves the problem of reentrainment and collection of dust in conventional baghouses