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1.
《Journal of Atmospheric and Terrestrial Physics》1978,40(4):421-428
Using a photometer equipped with a cooled photomultiplier RCA-C31034A and an optics consisting of three aspheric lenses, the O2(0–1) Atmospheric band at 8645 Å and the OH(8-3) band at 7274 Å are observed simultaneously from the ground level along with [OI] 5577 Å line, to investigate the instantaneous intensity changes. The P and R branches of O2(0–1) Atmospheric band and the P1(4), P2(4), [P1(3) + P2(3)] and [P1(2) + P2(2)] lines of the OH(8-3) band are spectrally clearly resolved. It is found that the O2(0–1) Atmospheric band and the OH(8-3) band covary fairly well in intensity; it seems that the correlation coefficient during the night lies around 0.500. Interrsity correlations between the OH(8-3) band and [OI] 5577 Å line are also investigated. It is found that the correlation coefficient during a night lies around −0.200 and thus the correlation between the OH(8-3) band and [OI] 5577 A line is weaker than that between the O2(0–1) Atmospheric band and the OH(8-3) band. Correlations among P1(4), [P1(3) + P2(3)] and [P1(2) + P2(2)] lines of the OH(8–3) band are studied, to find that their correlations are complete within an error of experiment; the correlation coefficient during a night ranges from 0.980 to 0.997. A midnight maximum of intensity of the OH(8-3) band is hardly found. During night the OH intensity always fairly fluctuates. 相似文献
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《Journal of Atmospheric and Terrestrial Physics》1984,46(3):265-271
The altitude distribution of the oxygen infrared atmospheric bands at 1.27 μm was measured during the total solar eclipse of 26 February 1979. The ozone concentration profile has been derived from these airglow measurements and indicates that at 85 km the concentration at totality was 7 × 1.7 cm−3, with no well defined upper layer. This reduced concentration, which is typical of summertime conditions, was probably due to perturbations in the mesospheric chemistry and transport induced by a winter warming event that was in progress at the time of the eclipse. At 60 km the ozone concentration, 2.7 × 1010 cm−3, was enhanced above that normally measured. This increase may also have been caused by the stratospheric warming event but the effects of a particle precipitation event, which was also in progress during the eclipse, may be important. 相似文献
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《Journal of Atmospheric and Terrestrial Physics》1990,52(1):47-57
Some results from 54 nights of simultaneous measurements, performed between 1984 and 1987, of rotational temperatures for the OH(6−2) and O2(1∑)(0–l) bands are presented. A summer enhancement by 15 K in O2 temperature has been found that has not formerly been observed in airglow measurements. At least five nights show prominent tide-like temperature oscillations with a phase shift between layers typical of upward wave propagation at about 10 km h−1, with up to 55 K variation. During other nights, similar oscillations are limited to the O2 layer. Data for different seasons seem to be characterized by different levels of variability. During the one equinox campaign, nocturnal temperature variations show an exceptionally stable pattern of tide-like oscillations. 相似文献
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《Journal of Atmospheric and Terrestrial Physics》1995,57(13):1623-1637
Spectra of the hydroxyl emissions in the wavelength range 1.0–1.6 μm, which originate at mesopause altitudes, have been obtained, using a Fourier transform spectrometer at Maynooth (53.2°N, 6.4°W), on all suitable nights during the period January–December 1993. Rotational temperatures and integrated band brightnesses have been calculated from the spectra of the OH(3, 1) and (4, 2) vibration-rotation bands. The mean annual temperatures calculated over all measurements were T(3, 1)=200±19 K and T(4, 2)=206±19 K, where the uncertainty represents the standard deviation on the measurements. Harmonic analysis of the nightly averaged temperature values revealed an amplitude of 27 ± 1 K and a phase of 95 ± 2 days in the annual variation of the (3, l) band at our latitude. The semiannual component was found to have an amplitude of 7 ± 1 K and a phase of −51 ± 9 days for this band. Results for the (4, 2) band were identical in both amplitude and phase for the annual component, while the semiannual component gave an amplitude of 8 ± 1 K and a phase of − 43 ± 7 days. These results are compared with data recorded by the SME satellite, and with the predictions of the MSISE-90 model for a station at 53° latitude. Temperatures predicted by the MSISE-90 model for Maynooth are consistently below the values obtained in this study by 15–20 K. Excellent agreement is observed between the absolute value of temperature, in the case of the SME satellite, and in the amplitude and phase of the annual variation predicted by MSISE-90. The phase of the semiannual component observed in our data deviates somewhat from the −99 ± 1 days predicted by MSISE-90.The annual mean brightness of the OH (3, 1) band was found to be 75 ± 18 kR, while that of the (4, 2) band was 106±26 kR. Diurnal variations generally showed a steady decrease from dusk to dawn, apart from a brief period in June and July. Monthly average values of band brightness have been calculated for each band and are compared with the predictions of a recent photochemical model (Le Texier et al., 1987). The model shows some elements of agreement with our observations, particularly a pair of maxima near the equinoxes, but it does not predict the broad winter maximum observed in both bands at this latitude. 相似文献
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《Byzantine and Modern Greek Studies》2013,37(1):165-185
AbstractAn analysis of the position of the Greek Communist Party (KKE) during the Greek-Italian war is interesting not only because it involves a hitherto unsolved puzzle – how and why the KKE's General Secretary, Nikos Zahariadis, wrote his ‘three letters’ – but also because, it involves background factors that help explain how the KKE emerged, during the occupation period, in possession of an invaluably useful ‘patriotic’ image. Such an image, obtained from Zahariadis' ‘first’ letter, undeniably facilitated the party's successful efforts to build up the country's largest liberation movement (EAM) and, through this movement, to come close to capturing power during the years 1943–4. 相似文献
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《Journal of Atmospheric and Terrestrial Physics》1994,56(9):1083-1090
Ozone amounts in the mesosphere have been determined from limb-scan observations made by the near infra-red channel of the Faza teleradiometer on board the orbital station ‘Salyut-7’ in October and November 1985. Altitude and latitude ozone and atomic oxygen density profiles were deduced. We have observed a secondary maximum of ozone density near 80 km. An error analysis shows that effects of random errors in the data are less than 10% between 45 and 75 km. 相似文献
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none 《Environmental Archaeology》2013,18(1):121-126
AbstractDuring the excavation of the circular fortress of Oost-Souburg, the Netherlands, objects of bone and antler were found: combs, needles, spindles, three-pronged objects, bone skates and points. The finds are dated between AD 900 and 975. In this contribution the objects which belong to the winter season, the bone skates and the points, are discussed. The skates occur in various types and are made of a variety of bones. Certain types of skate were used without bindings, others were either designed to be fastened to the feet or possibly were tied only at the heels. The roughly-made points that were found may be the points of the prickers used to propel the skater forward on his skates. 相似文献
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D. Frémondeau T. Cucchi F. Casabianca J. Ughetto-Monfrin M.-P. Horard-Herbin M. Balasse 《Journal of archaeological science》2012
Since domestication during the mid 11th millennium BP in the Near East and the 8th millennium BP in China, the pig has played an important role in human diet and economy. The objective of this study is to evaluate the potential of stable oxygen and carbon isotopes sequential analyses of pig tooth enamel to investigate pig seasonality of birth and diet, as these are important parameters for the reconstruction of pig herding strategies in ancient societies. 相似文献
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Marcos Martín Cenizo 《Alcheringa: An Australasian Journal of Paleontology》2013,37(4):493-514
New bird fossils from the Santa Cruz Formation (lower–middle Miocene), Santa Cruz Province, Patagonia, Argentina, are described. They represent an indeterminate species of the extinct anhingid Macranhinga and a new genus and species of basal Anatidae Ankonetta larriestrai. The record of the giant darter Macranhinga constitutes the southernmost record for the family, and expands the known stratigraphic range of the genus, previously restricted to the upper Miocene. Based on an analysis of the fossil anhingid record from South America, we hypothesize that giant darters disappeared from South America in the early Pliocene due to climatic deterioration, regression of marine and freshwater environments, the arrival of placental carnivorous mammals, and also probably by competition with phalacrocoracid cormorants. The new anatid Ankonetta is based on an incomplete but informative tarsometatarsus, with superficial similarities to extant Dendrocygna. A brief overview of several fossil ducks from the Patagonian Cenozoic concludes that most pre-Pliocene examples belong to non-anatine taxa, indicating that plesiomorphic ducks were the dominant anseriforms in those times, a pattern also evident on other continents. 相似文献
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The early mediaeval cemetery of Campochiaro is located in Molise (Central Italy) and dates to the 6th–8th centuries AD. It consists of two inhumation areas: one at Morrione and the other at Vicenne. This site is important because of the contemporary presence of locals, Lombards and Avars of the steppes. Campochiaro was probably an outpost against the Byzantine army settled in southern Italy. Since no signs of a stable settlement or built-up area have been found, it seems the cemetery can be attributed to a semi-nomadic group. Many graves contained a man and his horse with the harness complex and typical Avar stirrups. The military nature of this settlement is shown by ostearchaeological evidence of warfare and violence on three skeletal individuals: n. 20, n. 102 and n. 108. Two of them exhibit lesions of the cranial vault probably produced by shock weapons in the fashion of the Byzantine armies: a spiked mace and a battle-axe. The cicatrisation of the wounds and the bony neo-formation suggest that the individuals survived these injuries for a long time. The third individual suffered from leprosy. He shows a long perpendicular cut in the left section of the frontal bone. The wound is clean and, because it is without traces of bony neo-formation, was probably a peri-mortem blow landed with a sharp weapon. The wound was not mortal, because it was very slight and probably produced only a slash. As ritual or magical practises and/or damage produced during the excavation or by the action of roots in the earth can be excluded, this individual was perhaps really a leper warrior who died in combat. 相似文献
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On Cathars,Albigenses, and good men of Languedoc: [Journal of Medieval History, 2001, 27(2) 181–195]
《Journal of Medieval History》2001,27(4):417
This essay proposes a re-evaluation of how Cathars, Albigenses, and the heresy of the good men are studied. It argues that some commonplace notions about the Cathars, virtually unaltered for over a hundred years, are far from settled — especially when inquisition records from Languedoc are taken into account. This historiography rests upon an intellectualist and idealist bias, that, in the end, unwittingly restricts the historical imagination. This essay, by looking at some implications of this methodological tendency, suggests how the history of the Cathars, Albigenses, and the good men might be rethought. 相似文献
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The recently found metal casting mould from Gaj O?awski (SW Poland) was designed for the production of socketed axes typical for later stages of the Bronze Age in Poland (ca. 1100–900 bc). This unique artefact is a half of a durable, two-piece wedge-shaped mould and measures 17.5?×?7.2?×?4.0 cm. The surface of the mould is covered copper oxides and carbonates, and the remnant of beeswax was found on its inner surface. The metal forming mould consists of cored dendrites of Cu-dominated (Cu >96.5 wt%, up to 2.2 wt% Sn) and Cu impoverished (Cu ~86.0 wt%, Sn ~9.4 wt%, some Sb, As and Ag) end compositions and volumetrically subordinate α?+?δ eutectoid. The “as cast” structure of the metal shows that the mould was never used for molten metal casting. Since this kind of moulds was used for mass casting of metal, the Gaj O?awski one was probably never used, and the beeswax is the remain of its coating. This is the first remain of the Bronze Age beeswax described in metallurgical context in Europe. 相似文献
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Over the last 80 years Belgian, Dutch and German archaeologists working in the lower Rhine–Meuse–Scheldt basin have encountered a Roman pottery group that occurs in large quantities at most Roman sites in the region. Several researchers have separately tried to define this pottery, resulting in different names. Petrographic and geochemical analyses of 100 samples have now shown that the production of this ware predominantly made use of one source of raw material, divisible into three sub-groups on the basis of technological choices. The probable source lies in the early-Pleistocene Tegelen-formation, a clay rich in muscovite mica and garnet, which outcrops in the tertiary Scheldt escarpment (Nl) and the campine microcuesta (B). On the basis of geographical characteristics, Roman finds and the presence of a large Medieval pottery industry, production in the Bergen-op-Zoom area is suggested. In view of these new findings the name ‘Low Lands Ware 1’ is introduced to refer to this pottery group. 相似文献
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《Journal of Atmospheric and Terrestrial Physics》1987,49(11-12):1059-1069
The medium frequency radar (∼ 2.2 MHz) at Saskatoon has been run continuously since 1978 and the Meteor Radar at Monpazier ran continuously for ∼ 10 day intervals in most months of 1979/1980. The radars are separated by ∼ 8000 km. Because of the excellent quality of the data, spectral and harmonic analyses have been completed from ∼ 70 to 100km and oscillations with periods of ∼ 6h–6days studied.There are substantial similarities in the mean zonal winds, both with regard to magnitudes and times of seasonal reversals; also in annual and semi-annual oscillations. In general, the semi-diurnal tide has similar amplitudes, phases and vertical wavelengths : there are consistent summer (long λ) and winter (short λ) characteristics, with rapid transitions between them. Differences between the timing of these transitions and in some of the mid-season tides are discussed. The diurnal tide is less regular and of smaller amplitude at both locations, often being too small to reliably characterize at Monpazier. However, seasonal variations between summer and winter months may be discerned.In addition to the 24 and 12 h tidal oscillations, which traditionally are studied in most detail, there is clear evidence for additional osculations near 6,8, ∼ 10 and ∼ 16 h and longer periods of ∼ 2 and ∼ 5 days. The amplitudes of these are often comparable or larger than the ‘dominant’ 24 and 12 h tides. The monthly and seasonal variations of these additional oscillations are studied, as a function of height, at the two locations. There is evidence for large scale (global) and small scale (local) disturbances in the wind field. 相似文献
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We investigated fossil tooth enamel of mammals and crocodiles from two Mio-Pliocene East-African formations (Lukeino and Mabaget Fms) using infrared spectroscopy and chemical and stable-isotope analyses. Infrared spectra indicate that the fossil enamel contains biological apatite (bioapatite), without significant secondary carbonate contaminations. Several empirical infrared indexes were used to analyze the crystal–chemical characteristics of enamel. Fossil enamel has less organic matter, water and structural carbonate of apatite than modern enamel with which it was compared. Fossil apatite has a better crystallinity than bioapatite. The calcium/phosphorus mass ratio and the fluorine content of fossil apatite show intermediate values between bioapatite and geological fluorapatite. The samples also display significant crystal-chemical variations, depending on the vertebrate group (mammals vs. reptiles) and the taphonomic context (Lukeino Fm vs. Mabaget Fm). In spite of these changes, no relationship was observed between the chemical contents (carbonate and fluorine) and the stable-isotope ratios of carbonate (δ13C and δ18O) in fossil enamel. Preservation of the palaeoenvironmental signals is strongly supported by the fact that the stable-isotope composition of the three investigated fossil mammalian taxa (deinotheres, equids and hippos) is consistent with their ecological features. For instance, typical C3- and C4-plant isotope compositions are reflected in the deinotheres and equids, respectively, and amphibious hippos display lower δ18O values than terrestrial herbivores, as expected. 相似文献
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Starch residue, pollen and phytolith analysis was carried out on coralline deposits from a c. 3050–2500 cal. yr BP Lapita site at Bourewa, Viti Levu, Fiji. Starch grains, calcium oxalate crystals and xylem cells of introduced Colocasia esculenta and Dioscorea esculenta were identified, involving a process of elimination of possible taxa by cross-correlation of microfossil types. The data provide an eastward extension of direct evidence of Lapita horticulture in Remote Oceania previously identified in Vanuatu. 相似文献