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1.
Alepotrypa Cave, one of the richest and best preserved Neolithic sites in Greece, was occupied by early farmers from ca. 5000 to 3200 BC . Study of human remains from this site contributes important information to the bioarchaeological record for this period. The remains are from the cave's Ossuary II, a secondary deposit containing the disarticulated remains of at least 20 individuals, including adults and sub‐adults. A high frequency of porotic hyperostosis and cribra orbitalia suggests the presence of chronic iron deficiency anaemia. A combination of two possible factors could explain this situation, including reliance on an iron‐deficient cereal diet, and presence of high pathogen and parasitic loads resulting from poor hygiene and contamination of the communal water source. These lesions may also be related to some type of inflammatory process. Some 31% of individuals display healed cranial depressed fractures, indicating evidence of violent (non‐lethal) confrontations. Stable isotope analysis reveals a predominantly terrestrial C3 diet, with little evidence of marine food consumption, despite close proximity to coastal resources. The presence of various domesticated plants suggests that these C3 foods may have been agricultural. Moreover, a high frequency of dental caries is consistent with a diet involving significant carbohydrate consumption. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   

2.
Rickets is caused by vitamin D deficiency as a result of limited exposure to sunlight and inadequate diet. In the 19th century, rickets was endemic in most northern European cities. In post‐Medieval Netherlands, rickets is documented in low frequencies in a few urban samples, but has not been studied in contemporaneous rural populations. Beemster is a rural farming community in the Netherlands that was established in the 17th century upon drained land, with the Middenbeemster cemetery in use until 1866 AD. Ninety‐five individuals from the ages of 32 weeks in utero to 15 years were examined for rickets in order to understand factors that can cause vitamin D deficiency in rural, non‐industrialized populations. To identify rickets in the Beemster sample, ten features were scored, with bending deformities of the lower limb and one other feature, or at least three non‐bending features, having to be present in order for diagnosis. Nine individuals (9.5%) had evidence of rickets—a high prevalence, especially for a rural community where ample sunlight was available. The two and three year old Beemster infants were most heavily affected with an age‐specific prevalence of 30.4%. Two three‐month‐old infants also had rickets. Some of the affected may have developed rickets secondarily, as a result of a different illness, but cultural practices including prolonged swaddling, occlusive clothing, and keeping the young indoors, are suggested to have contributed to this high rickets prevalence. Dietary variables including poor weaning foods and common episodes of malnutrition may have also contributed to vitamin D deficiency. This study demonstrates the value of careful analysis of pathological conditions in subadults and highlights that rickets was not only a disease of cities, but affected populations that would appear to have been at low risk, because of maladaptive cultural practices. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

3.
More than 400 fayalitic bloomery slags from prehistoric iron production sites in Upper and Lower Lusatia, eastern Germany, as well as bog iron ore samples and intermediary samples of the smelting process, were analysed by chemical and mineralogical techniques. While the precursor bog iron ores exploited in the two regions under investigation were very similar in composition, consisting of low‐manganese/low‐barium as well as high‐manganese/high‐barium types of ore, pronounced differences in slag composition were detected. Slags from 17 investigated sites in Upper Lusatia showed average P2O5 contents between 1 and 3 mass%, whereas slags from 15 investigated sites in Lower Lusatia were generally much richer in phosphorus, reaching values as high as 7 mass% P2O5. Since a reasonable correlation exists between calcium and phosphorus contents in the slags of the latter sites, it is conjectured that deliberate addition of CaO to the ore/charcoal charge of the bloomery furnace may have taken place in order to fix the phosphorus in the slags effectively. In many samples, this conjecture is being supported by the detection of a slag mineral Ca–Fe phosphate Ca9?xFe1+x(PO4)7 that presumably crystallized from a residual phosphorus‐rich melt and shows a cotectic relationship to both Ca‐rich fayalite and wustite, as well as to members of the solid solution series magnetite–hercynite.  相似文献   

4.
Koji pottery is a glazed ceramic art used widely for figurines. In early Taiwan, it was employed in temple construction for decorative purposes. Ye Wang (1826–87) is the first historically documented Koji artist of Taiwan and also the most prominent Koji pottery artist, noted for his modelling and glazing skills. Unfortunately, his unique technique was lost following his death in 1887. In order to provide vital information for ongoing conservation work on Koji pottery, this study analysed the physical and chemical characteristics of Ye Wang's gem‐blue glaze, to discover the glaze formula. DSC combined with the two‐thirds rule revealed that the firing temperature of Ye Wang's works of art was most probably around 878–923°C. EPMA revealed that the gem‐blue glaze has high alkali levels, and belongs to the PbO–K2O–B2O3–Na2O–SiO2 system, deriving its unique colour from copper, iron, manganese and cobalt. This study found high potassium levels in the gem‐blue glaze, which are generally a characteristic of traditional Chinese glazes. In addition, a unique discovery of boron, commonly used in famille rose, was also identified in the glaze. By comparing spectra of historical and reconstructed glazes and adjusting the proportion of chromophoric elements, this study found a glazing formula with colours close to those of Ye Wang's gem‐blue glaze.  相似文献   

5.
The glaze chemistry of a group of rustiques figulines attributed to the renowned French potter Bernard Palissy (1510–90), or to his followers and imitators, has been determined non‐destructively using PIXE and PIGE analyses. The glazes are all lead silicates, the colourants being transition metal oxides—CuO, CoO, MnO and Fe2O3—with a small addition of SnO2 to some of the glazes being common. Some distinction can be made between the various fabricated objects based on details of the overall composition and on the concentrations of the various colourants. The presence of B2O3 in any glaze, even in quantities as small as 0.1–0.3%, indicates a post‐16th century production. Additionally, B2O3 in larger quantities, a few per cent or greater, very probably indicates an 18th–19th century production. However, at least one object known to be of 19th century production contains no B2O3.  相似文献   

6.
In the Neolithic and Copper Age collective burials of the Portuguese Estremadura, the majority of material culture and skeletal remains are highly commingled, making it difficult for archaeologists to evaluate social status by linking individuals with specific grave goods. In these circumstances, bio‐anthropological data about individual life histories offer an additional avenue of investigation into social complexity among prehistoric communities practising collective burial. In this study, stable isotope data were gathered from 81 individuals from seven collective burial sites and one settlement, the fortified site of Zambujal, in order to determine if significant dietary differences exist within or between burials that may point to patterns of social differentiation, both at individual sites and across the region. While in general all of the sampled individuals consumed fairly homogeneous diets based on terrestrial animal proteins and C3 plants, this study found that statistically significant differences in δ13Cap and δ15N values exist between several sites, which may indicate socially differentiated consumption of meat and plants. Additionally, statistically significant differences were found in δ15N values between adults and juveniles, which may either be attributable to protein‐restrictive child‐feeding practices or physiological processes related to skeletal growth and development.  相似文献   

7.
The results from a magnetic survey and archaeomagnetic investigation of a medieval brick kiln at Kungahälla in Bohuslän (south‐west Sweden) are reported. Detailed magnetic total field and magnetic gradient measurements over known traces of the kiln showed marked local magnetic anomalies of up to 200 nT, revealing the rectangular shape of the kiln remains. Palaeomagnetic investigations of the remanent magnetization of 12 bricks from the kiln floor gave precise definitions of both the direction of the archaeomagnetic field [(Dm, Im) = (66.7°, 8.8°), k = 655, α95= 1.7°] and the palaeointensity [Bm= 69.0 ± 3.6 µT]. An archaeomagnetic date is obtained by comparing the direction of the archaeomagnetic field found in the kiln with a geocentral dipole‐transformation of the British master‐curve for secular variation. Of two possible archaeomagnetic dates (ad 1280 ± 50 or ad 1480 ± 50), the ad 1280 ± 50 age is in good accordance with the C‐14 ages and archaeological dates as well as with direct historical evidence, whereas a c. 100 years younger TL date appears to be too young.  相似文献   

8.
A study was made of the dynamics of the main ionospheric trough in the northern and southern hemispheres using data of ion density winter measurements on the Kosmos-900 satellite from 1977 to 1979. Significant longitudinal variations of the trough position have been found which prove to be different in the different hemispheres: in the northern hemisphere they have the shape of a double wave (period 180° longitude) with an amplitude of 4–6° of latitude by both day and night whereas, in the southern hemisphere, they exhibit a simple wave (period 360° longitude) with amplitude of about 6° in the night hours and 10–12° of latitude in the day hours.The analysis of the IMF influence on the trough position by day and night has shown both BZ and BY to affect the shift of the ionospheric trough. It has been found that in the northern hemisphere the vertical and azimuthal IMF components act in opposite phase while in the southern hemisphere the effects of the two components are added. Analytic relationships between the trough shift magnitude and the values of BZ and BY are discussed.  相似文献   

9.
X. R. Ming  L. Liu  M. Yu  H. G. Bai  L. Yu  X. L. Peng  T. H. Yang 《Geofluids》2016,16(5):1017-1042
This study investigates the Wangfu Depression of the Songliao Basin, China, as a natural analogue site for Fe migration (bleaching) and mineralization (formation of iron concretions) caused by reducing CO2‐bearing fluids that leak along fractures after carbon capture, utilization, and storage. We also examined the origin of fracture‐filling calcite veins, the properties of self‐sealing fluids, the influence of fluids on the compositions of mudstone and established a bleaching model for the study area. Our results show that iron concretions are the oxidative products of precursor minerals (pyrite and siderite) during uplift and are linked to H2S and CO2 present in early stage fluids. The precipitation of calcite veins is the result of CO2 degassing and is related to CO2, CH4, and minor heavy hydrocarbons in the main bleaching fluids. In our model, fluids preferentially enter high‐permeability fracture systems and result in the bleaching of surrounding rocks and precipitation of calcite veins. The infilling of calcite veins significantly decreases the permeability of fractures and forces the fluids to slowly enter and bleach the mudstone rocks. The Fe2+ released during bleaching migrates to elsewhere with the solutions or is reprecipitated in the calcite veins and iron concretions. The formation of calcite veins reduces the fracture space and effectively prevents fluid flow. The fluids have an insignificant effect on minerals within the mudstone. In terms of the chemistry of the mudstone, only the contents of Fe2O3, U, and Mo change significantly, with the content of U increasing in the mudstone and the contents of Fe2O3 and Mo decreasing during bleaching.  相似文献   

10.
Samples of celadon were collected from the Altar Guan Kiln in Hangzhou, and from the Xiaomeizhen and Xikou Kilns, two subordinate kilns of the Longquan Kiln producing black‐body celadon called Literature Ge. Both the elemental contents in the sample bodies and the glaze were measured. The results reveal that the sample bodies contain fingerprint information for provenance, while this was lost in the glaze during the production process. The TiO2, MnO and Rb2O contained in the bodies are fingerprints to distinguish between celadons from the Xiaomeizhen and Xikou Kilns. In the Altar Guan Kiln, some low‐TiO2 samples were found and their body colour is much lighter than some others, but they do not differ with regard to iron content. This indicates that both titanium and iron are indispensable for the blackness of the bodies: they may react to form some black minerals during the firing process. Ultimately, samples from the Literature Ge and Altar Guan Kilns differ in their body constituents. Principal component analysis reveals that the samples can be divided into two groups, corresponding to the two different areas.  相似文献   

11.
The effects of the IMF radial (Bx) and azimuthal (By) components on the distribution of polar cap arcs are examined using all-sky camera data from Vostok station for the winter months of 1977–1985. We conclude that three factors control the character of the aurora distribution: the type of the sector structure, the IMF radial component, and the IMF azimuthal component. Based on the experimental results, the following scheme for the auroral distribution in the northern and southern polar caps for different signs of Bx and By is put forward. The ‘garden hose’ structure (Bx > 0, By < 0 or Bx < 0, By > 0) produces symmetric auroral distributions in the morning and evening sectors of both the northern and southern polar caps; the ‘orthogonal garden hose’ structure (Bx > 0, By > 0 or Bx < 0, By < 0) is evidently inefficient in the production of aurorae. The Bx component determines the intensity of aurorae in that polar cap where geomagnetic field lines are in the opposite direction to the IMF (Bx < 0 in the case of the northern cap, and Bx > 0 for the southern cap) and produces the daytime auroral belt poleward of the auroral oval and parallel to it. The By component affects the auroral appearance in the morning or evening sectors of the polar cap, depending on its sign, and acts asymmetrically in the opposite polar cap. The appropriate patterns of plasma filament distributions in the high-latitude tail lobes are proposed. The characteristics of auroral movements affected by the By component (such as the direction and speed of the arc motion and the magnitude of displacements) are examined.  相似文献   

12.
Numerical simulations of multiphase CO2 behavior within faulted sandstone reservoirs examine the impact of fractures and faults on CO2 migration in potential subsurface injection systems. In southeastern Utah, some natural CO2 reservoirs are breached and CO2‐charged water flows to the surface along permeable damage zones adjacent to faults; in other sites, faulted sandstones form barriers to flow and large CO2‐filled reservoirs result. These end‐members serve as the guides for our modeling, both at sites where nature offers ‘successful’ storage and at sites where leakage has occurred. We consider two end‐member fault types: low‐permeability faults dominated by deformation‐band networks and high‐permeability faults dominated by fracture networks in damage zones adjacent to clay‐rich gouge. Equivalent permeability (k) values for the fault zones can range from <10?14 m2 for deformation‐band‐dominated faults to >10?12 m2 for fracture‐dominated faults regardless of the permeability of unfaulted sandstone. Water–CO2 fluid‐flow simulations model the injection of CO2 into high‐k sandstone (5 × 10?13 m2) with low‐k (5 × 10?17 m2) or high‐k (5 × 10?12 m2) fault zones that correspond to deformation‐band‐ or fracture‐dominated faults, respectively. After 500 days, CO2 rises to produce an inverted cone of free and dissolved CO2 that spreads laterally away from the injection well. Free CO2 fills no more than 41% of the pore space behind the advancing CO2 front, where dissolved CO2 is at or near geochemical saturation. The low‐k fault zone exerts the greatest impact on the shape of the advancing CO2 front and restricts the bulk of the dissolved and free CO2 to the region upstream of the fault barrier. In the high‐k aquifer, the high‐k fault zone exerts a small influence on the shape of the advancing CO2 front. We also model stacked reservoir seal pairs, and the fracture‐dominated fault acts as a vertical bypass, allowing upward movement of CO2 into overlying strata. High‐permeability fault zones are important pathways for CO2 to bypass unfaulted sandstone, which leads to reduce sequestration efficiency. Aquifer compartmentalization by low‐permeability fault barriers leads to improved storativity because the barriers restrict lateral CO2 migration and maximize the volume and pressure of CO2 that might be emplaced in each fault‐bound compartment. As much as a 3.5‐MPa pressure increase may develop in the injected reservoir in this model domain, which under certain conditions may lead to pressures close to the fracture pressure of the top seal.  相似文献   

13.
The Upper Triassic Mercia Mudstone is the caprock to potential carbon capture and storage (CCS) sites in porous and permeable Lower Triassic Sherwood Sandstone reservoirs and aquifers in the UK (primarily offshore). This study presents direct measurements of vertical (kv) and horizontal (kh) permeability of core samples from the Mercia Mudstone across a range of effective stress conditions to test their caprock quality and to assess how they will respond to changing effective stress conditions that may occur during CO2 injection and storage. The Mercia samples analysed were either clay‐rich (muddy) siltstones or relatively clean siltstones cemented by carbonate and gypsum. Porosity is fairly uniform (between 7.4 and 10.7%). Porosity is low either due to abundant depositional illite or abundant diagenetic carbonate and gypsum cements. Permeability values are as low as 10?20 m2 (10nD), and therefore, the Mercia has high sealing capacity. These rocks have similar horizontal and vertical permeabilities with the highest kh/kv ratio of 2.03 but an upscaled kh/kv ratio is 39, using the arithmetic mean of kh and the harmonic mean of kv. Permeability is inversely related to the illite clay content; the most clay‐rich (illite‐rich) samples represent very good caprock quality; the cleaner Mercia Mudstone samples, with pore‐filling carbonate and gypsum cements, represent fair to good caprock quality. Pressure sensitivity of permeability increases with increasing clay mineral content. As pore pressure increases during CO2 injection, the permeability of the most clay‐rich rocks will increase more than carbonate‐ and gypsum‐rich rocks, thus decreasing permeability heterogeneity. The best quality Mercia Mudstone caprock is probably not geochemically sensitive to CO2 injection as illite, the cause of the lowest permeability, is relatively stable in the presence of CO2–water mixtures.  相似文献   

14.
Hip fractures have high incidence rates in many current groups and are associated with high morbidity, mortality, and considerable expenditure. Although hip fractures associated with significant traumatic events can occur at any age, many hip fractures occur in older adults. To date, few hip fractures have been reported from archaeological skeletal material, and a number of hypotheses have been suggested for this. This research presents a comprehensive assessment of hip fractures in archaeological bone; 1597 adult (18+ years) skeletons from eight urban post‐medieval sites from England dating from the 18th and 19th centuries were recorded, and contemporary medical texts reviewed. This adult sample included 834 males and 652 females as well as 11 persons of undetermined sex. Ways of classifying and describing fractures in the clinical literature were reviewed and a methodology applicable to paleopathology determined. Of this sample, 15 (0.94%) had fractures in the femoral neck or intertrochanteric area: nine males, four females, and two individuals of undetermined sex. The numbers of fractures in males were interesting and most likely represent examples of accidental trauma as well as osteoporosis‐related fractures, the latter receiving growing awareness in recent clinical literature. Overall there was an age‐related trend with more individuals aged 50+ years with fractures than in other age categories. Underlying osteoporosis was potentially a complicating factor in five individuals and was likely associated with a vitamin D deficiency osteomalacia and a metastatic neoplastic condition in a further two cases. Fractures occurring close to the time of death and healed fractures were observed, indicating that the risk of mortality following this trauma was not consistent across this 18th and 19th century sample. Skeletal and historical evidence presented in this study indicate that the impact of hip fracture injuries varied, with survival likely linked to the fracture type. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

15.
Most researchers in the Proterozoic eastern Mt Isa Block, NW Queensland, Australia, favour magmatic fluid and salt sources for sodic‐(calcic) alteration and iron oxide–copper–gold mineralization. Here we compare spatial, mineralogic and stable isotope data from regional alteration assemblages with magmatic and magmatic‐hydrothermal interface rocks in order to track chemical and isotopic variations in fluid composition away from inferred fluid sources. Tightly clustered δ18O values for magnetite, quartz, feldspar and actinolite for igneous‐hosted samples reflect high temperature equilibration in the magmatic‐hydrothermal environment. In contrast, these minerals record predominantly higher δ18O values in regional alteration and Cu–Au mineralization. This dichotomy reflects partial equilibration with isotopically heavier wallrocks and slightly lower temperatures. Increases in Si concentrations of metasomatic amphiboles relative to igneous amphiboles in part reflect cooling of metasomatic fluids away from igneous rocks. Variations in XMg for metasomatic amphiboles indicate local wallrock controls on amphibole chemistry, while variations in XCl/XOH ratios for amphiboles (at constant XMg) indicate variable aH2O/aHCl ratios for metasomatic fluids. Biotite geochemistry also reflects cooling and both increases and decreases in aH2O/aHCl for fluids away from plutonic rocks. Decreased aH2O/aHCl ratios for metasomatic fluids reflect in part scavenging of chlorine out of meta‐evaporite sequences, although this process requires already saline fluids. Local increases in aH2O/aHCl ratios, as well as local decreases in δ18O values for some minerals (most notably haematite and epithermal‐textured quartz), may indicate ingress of low salinity, low δ18O fluids of possible meteoric origin late in the hydrothermal history of the region. Taken together, our observations are most consistent with predominantly magmatic sources for metasomatic fluids in the eastern Mt Isa Block, but record chemical and isotopic variations along fluid flow paths that may be important in explaining some of the diversity in alteration and mineralization styles in the district.  相似文献   

16.
In this research, we studied the compositional, crystallographic and microstructural properties of a series of incuse silver didrachmae stemming from the Achaean colonies of Metapontum and Caulonia. In this paper, we address the following points: (i) the metal sources, (ii) the fabrication process and (iii) degradation phenomena, such as incrustation and embrittlement. In this investigation, we employed energy‐dispersive X‐ray fluorescence spectroscopy, X‐ray diffractometry, and scanning electron and optical microscopies. The patina is mainly composed of chlorargirite. The coins consist of a silver‐rich alloy containing ~ 1% of Au and Cu. Metallographic and local compositional analyses revealed a complex scenario of inclusions. In one instance, unalloyed copper grains, two‐phase copper/bismuth globuli and high‐bismuth filaments were observed. In other cases, globular Cu 2 S (chalcocite) inclusions were noticed. The presence of SiO 2 and iron oxide inclusions is ubiquitous in these samples. Distorted twin lines and strain lines can be detected, denoting work‐hardening of recrystallized flans. Grain polygonalization can occasionally be noticed, hinting at secondary recrystallization processes. The irregularly shaped iron oxide particles often act as crack initiation sites. Fracture facets are generally intergranular. On some areas, intergranular decohesion is also observed. Open cracks sometimes contain AgCl. The strain lines that can be noticed on the fracture surfaces indicate work‐hardening and residual microstructural deformation. Information regarding inclusions and the presence of significant amounts of gold can be tentatively used to address provenancing and fabrication issues.  相似文献   

17.
Infant and child skeletons (n = 369) from the pre‐Columbian Grasshopper Pueblo site in east‐central Arizona (US) dating from the 14th century AD were examined macroscopically and with low‐power microscopy. They were studied as a representative example of a typical Mogollon community with respect to frequencies of deficiency and inflammatory diseases. First results revealed very poor living conditions, which are characteristic for this time period in the North American Southwest because of lack of food due to climatic and political changes. Thus, non‐specific stress indicators were frequently observed. In the group of deficiency diseases, anaemia was found in more than 50% of individuals, and in the group of inflammatory diseases, meningeal irritations were diagnosed in more than 70%. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

18.
This article examines discourses on emotion produced and circulated in the context of spiritual reform in sixteenth‐century Spain as teleological methods of self‐interpretation which nonetheless stressed the individuals’ responsibility in actively recognising, displaying, and directing their emotions to a spiritual purpose. Paying particular attention to key devotional books such as Ignatius of Loyola's Spiritual Exercises, Francisco de Osuna's Third Spiritual Alphabet, Bernardino de Laredo's Ascent of Mount Sion, and Teresa of Avila's Book of her Life and The Way of Perfection as a framework of beliefs and guidelines which helped to shape actual cultural practices such as self‐examination and meditation, it seeks to show the complexity of sixteenth‐century understandings of emotion, rationality and the role of the will. It thus aims to challenge the narrow approach taken by recent philosophers like Ronald de Sousa and Robert Solomon in their critique of the historical role of emotion within religion.  相似文献   

19.
Systematic changes of the position of the dipole axis of the Earth's magnetic field with respect to the solar axis induce distinct daily and seasonal variations of the vertical Bz-component in the solarmagnetospheric coordinate system (BZSM). Depending on the direction of the interplanetary magnetic field (IMF), negative BZSM- values are produced in spring by T polarity and in autumn by A polarity, whereas in the diurnal variation lowest BZSM-values have been calculated to occur near 23 UT for T, and near 11 UT for A polarity, respectively. In different ionospheric and geomagnetic parameters measured at high and midlatitudes increased precipitation of high energetic particles into the lower thermosphere and upper mesosphere has been detected during periods with negative BZSM-components. The seasonal variation of the parameters investigated, with maximum values near the equinoxes, as well as a part of their diurnal variations, can thus be explained by particle precipitation being markedly controlled by the IMF sector structure.  相似文献   

20.
Sharp decreases in ΦoF2 are found to occur frequently in the nighttime low-latitude ionosphere after southward turning of the IMF Bz component, especially under isolated Bz turnings, i.e. when the IMF has been northward for at least 6 h before its turning. These decreases occur simultaneously (within a 1-h time interval) with the Bz turning. The effect is observed both when a substorm or a magnetic storm begins after Bz has turned southward, and when a noticeable substorm does not occur. The effect is more pronounced after midnight and a maximum at 03 LT. Short-term (with scale times of about 1 h) variations of ΦoF2 and hmF2 for Bz southward turning are analysed using a large amount of ground-based and topside sounding data. The decreases in ΦoF2 are shown to occur at first over the magnetic equator and then, during the second hour after the turning, at the crests of the equatorial anomaly. The ionosphere returns to its undisturbed state, on average, in 4–5 h (if other disturbing agents do not arise). These decreases are suggested to be caused by modifications in the electric field in the low-latitude ionosphere associated with Bz southward turning.  相似文献   

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