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91.
92.
Vít Kárník 《Studia Geophysica et Geodaetica》1958,2(4):400-401
Резюме Приводятся результаты анализа записей двух камерных взрывов, имевших место 15-го Февраля 1958 г. в Баварии. Взрывы были регистрированы
двумя вертикальными электродинамическими сейсмографами, иаготовленными в Геофизическом институте ЧСАН и назначенными для регистравии
слабых тектонических толчков.
Address: Boční II, Praha 13-Spořilov. 相似文献
Address: Boční II, Praha 13-Spořilov. 相似文献
93.
94.
Anders Bøyum 《Aquatic Sciences - Research Across Boundaries》1970,32(1):300-327
Summary Chemical and physical properties in 12 lakes in the north-easternmost part of Norway are studied. Geologically the lakes are
situated on the pre-cambrian “Baltic shield”, with metamorphic and intrusive rocks that are not easily soluble.
Vertical series of temperature, pH, O2 and x18 together with colour measurements and transparency indicate that the lakes are temperate and fundamentally oligotrophic,
some with a dystrophic character. Some individual differences are discussed, with special reference to the surroundings, flow-through
rate and morphometry.
In accordance with the geology of the area the amount of electrolytes is small. Major ions (Ca, Mg, Na, K, HCO3, SO4 and Cl) are analysed. The greatest differences in the composition of these ions in the lakes are shown to be due mainly to
the varying proximity to the sea and to geological differences.
Rain is shown to be the most important factor in supplying major ions toat least some of the lakes. Individual variations
are discussed, and comparisons are made with the ionic composition of water in other districts.
Zusammenfassung An 12 im n?rdlichesten Teil von Norwegen, auf dem pr?kambrischen Baltischen Schild gelegenen Seen werden die chemischen und physikalischen Eigenschaften studiert. Das Einzugsgebiet besteht aus schwerl?slichem, metamorphem und intrusivem Gestein. Die vertikale Verteilung von Temperatur, pH, O2 und x18 samt Farbmessungen und Transparenz zeigt, dass die Seen dem temperierten Typus angeh?ren und im wesentlichen oligotroph sind, einige von dystrophem Charakter. Einige individuelle Unterschiede werden er?rtert mit besonderer Berücksichtigung der Umgebung, der Durchflutungszeit und der Morphometrie. In übereinstimmung mit der geologischen Beschaffenheit der Umgebung ist der Elektrolytgehalt neigdrig. Die dominierenden Ionen (Ca, Mg, Na, K, HCO3, SO4 und Cl) werden analysiert. Es wird nachgewiesen, dass die gr?ssten Unterschiede in der Zusammensetzung dieser Ionen in den Seen auf die verschiedene Entfernung vom Meer und auf geologische Unterschiede zurückzuführen sind. Für einige der Seen wird nachgewiesen, dass der Regen als wichtigster Faktor für ihre Versorgung mit Ionen anzusehen ist. Es werden individuelle Unterschiede er?rtert und Vergleiche mit der ionalen Zusammensetzung von Gew?ssern anderer Gegenden gezogen.相似文献
95.
Summary The core waves recorded at four seismograph stations in Central Europe were investigated with the aim to find the most suitable set of travel-time curves and a fitting model of the core structure. Another travel-time curve was constructed by means of time differences between the core phases. The differences in the features of the travel-time curves were studied using records of shallow, intermediate and deep shocks from the same focal region (Tonga). 相似文献
96.
We study two long transequatorial loops connecting high-latitude regions of the new solar cycle. These loops (with lengths of 47 and 61 heliographic degrees) provide evidence that the upper length limit of 37° found by Chase et al. (1976) from Skylab data was determined simply by the typical distances between northern and southern active regions during the period of Skylab observations. We find strong support for the idea that these long interconnecting loops originate through reconnection of field lines extending from the two active regions towards and beyond the equator, and confirm the earlier finding by Canfield, Pevtsov, and McClymont (1996) that only field lines from active regions with the same chirality reconnect. As we are not aware of any longitudinal (E–W) loops of comparable lengths, we suggest that it is mainly the solar differential rotation which drives the reconnection of latitudinal (N–S) field lines. 相似文献
97.
Wolf Tietze Gerhard Kortum W. R. Mead T. K. Poiker C. Paddick George Kish A. Njøs H. Mensching V. Haarmann Uzo M. Igbozurike M. M. Yoshino Mushtaqur Rahman Lage Wahlström J. Connell Kazimierz Dziewonski Wayland R. Swain J. Humlum G. W. Lüttig Haruko Kishimoto Mai Britt E. Mørk 《GeoJournal》1982,6(3):270-280
98.
Two new Th ii lines have been identified in the spectrum of the solar photosphere. The abundance derived from these lines together with the previously known Th ii line at 4019 Å, is log
Th = 0.85 ± 0.20 in the log
H = 12.00 scale. Analysis of three Pb i lines in the photospheric spectrum resulted in an abundance of log
pb = 1.90 ± 0.10. The solar Th/Pb ratio is:
Th/
Pb = 0.09
-0.005
0.09
. 相似文献
99.
High resolution spectral observations between 500 MHz and 550 MHz on 1972 October 25, revealed an emission event of special interest. The main feature was bursts with a single frequency duration of about 0.09 s and with a bandwidth of the same order of magnitude as the band covered by the spectrograph. The bursts occurred in showers' which lasted for one or two minutes and which were separated by quiet intervals of roughly the same length. Frequently the activity assumed a periodic nature. Periods between 0.1 s and 0.3 s were found. The most remarkable feature of the records was a very large number of bursts with the same duration as the wide band bursts, but showing a bandwidth of a mere 1–2 MHz.The wide band bursts may be plasma waves excited by proton streams trapped in coronal magnetic fields and the narrow band bursts may possibly be explained as perpendicular electrostatic electron cyclotron waves. 相似文献
100.
H.K. Myrabø 《Planetary and Space Science》1984,32(2):249-255
Atmospheric temperatures from the polar mesopause are deduced from spectrophotometric measurements of hydroxyl bands and lines in the night airglow made at 78°N during December and January 1980/81 and 1982/83. An overall mean temperature of 220 K is found with a range from 172 to 257 K in the daily mean values. Several warm periods lasting 3–6 days may be due to heat dissipated by gravity waves. One week of consistently low temperatures was apparently connected to a stratospheric warming. Both datasets show a warmer mean temperature later in January than for early and mid-December. The polar OH airglow seems to peak at or just above the mesopause. The data also indicate that the mesopause is situated at approx. 90 km with an upper temperature gradient of 1 K km?1 indicating a very shallow mesopause. A superposed epoch analysis of 19 consecutive 24-h periods reveals a semidiurnal variation in the temperature around winter solstice with an amplitude of 5 K. No diurnal variation of amplitude greater than 1 K is apparent. Average wind velocity deduced from the amplitude of the semidiurnal temperature variation is 9 m s?1. 相似文献