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391.
Marcela Laštovičková Karel Klíma Reviewer A. Janáčková 《Studia Geophysica et Geodaetica》1988,32(1):78-83
Summary The new for measuring the electrical conductivity of rocks and minerals developed in the Geophysical Institute is briefly discussed. Unlike the earlier method it uses a PMD-85-1 microcomputer and related equipment (all of CMEA production), which enable the automatic control of the experiment, collection, evaluation, graphic display and storage of the results. This method is verified by measuring the electrical conductivities of granitoids.
am nua m¶rt; uu mn¶rt;mu n¶rt; u ua ¶rt;a uu umumm . muuu m n¶rt;u¶rt; m¶rt;a unm unmPMD-85-1 u nua¶rt;au nuuu ( nu¶rt;ma ), m nm mm amamu nau numa, , am,au uau u anu mam uu. mm m¶rt; nm n uu mn¶rt;muaumu¶rt;.相似文献
392.
西方城市女性时空行为研究的新趋势及其对中国的启示 总被引:1,自引:1,他引:0
为满足当前城市社会发展与城市建设需要,西方女性时空行为研究近年来取得了长足进展,研究主题覆盖行为特征、社会公平、可持续性等方面。中国城市女性在转型期同样面临着重大的挑战,城市空间的性别不平等正在深刻地影响女性的日常行为与生活质量。本文系统梳理了近50年来西方女性时空行为研究成果,介绍了女性通勤行为、非工作活动等传统议题和家庭关系、联合行为、可达性等新问题的研究进展,并总结了女性时空行为研究的理论解释。西方女性时空行为研究早期关注经济转型背景下的女性出行行为,对就业可达性、通勤和非工作活动的性别差异进行了大量研究。近年来,西方研究呈现出多元化趋势,研究重点转向家庭关系、家庭联合行为与时空可达性等新主题,指出女性在日常生活中面临社会排斥与空间不平等。为理解女性时空行为模式的形成机制,学者从经济学、社会学、地理学等角度进行探讨,提出了地租与工资理论、劳动力市场隔离理论、家庭责任假说、女性的自我认知与社会文化、家庭资源分配说、时空固定性制约等解释理论。这些研究为中国城市女性时空行为研究提供了借鉴。针对中国女性面临的城市社会转型的独特背景,其时空行为受制度、家庭和自身的多重制约,提出了中国城市女性时空行为研究的框架和未来研究方向。 相似文献
393.
J. E. Ortiz T. Torres Y. Yanes C. Castillo J. De La Nuez M. Ibez M. R. Alonso 《第四纪科学杂志》2006,21(3):287-306
Aminochronological and aminostratigraphical methods have been used to study the Quaternary aeolian deposits from the islands located east of the Canary Archipelago (Fuerteventura and Lanzarote islands and La Graciosa, Montaña Clara and Alegranza islets). The extent of racemisation/epimerisation of four amino acids (isoleucine, aspartic acid, phenylalanine and glutamic acid) was measured in land snail shells of the genus Theba. The age calculation algorithms of these amino acids have been determined to permit the numerical dating of these deposits. Eight Aminozones, each defining dune/palaeosol‐formation episodes, have been distinguished and dated at 48.6 ± 6.4, 42.5 ± 6.0, 37.8 ± 4.6, 29.4 ± 4.8, 22.4 ± 4.5, 14.9 ± 3.6, 11.0 ± 4.0 and 5.4 ± 1.1 ka BP, the first five of them defining cycles of 5–7 ka. The alternation of palaeosols and aeolian deposits, which are related to abrupt transitions from humid to arid conditions, are the reflection of globally induced changes in North Africa palaeoenvironmental conditions linked to the effect of African palaeomonsoons on the trade winds and the Saharan Air Layer. Probably these aeolian cycles, with a recurrence period of 5–7 ka, are the expression of multiples of the ~2.4 ka solar‐cycle. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
394.
Stephen Serjeant † Alberto Carramiñana † Eduardo Gonzáles-Solares Phillipe Héraudeau Raúl Mújica † Ismael Perez-Fournon Nicola Sedgwick † Michael Rowan-Robinson Alberto Franceschini Thomas Babbedge Carlos del Burgo Paolo Ciliegi reas Efstathiou Fabio La Franca Carlotta Gruppioni David Hughes Carlo Lari Seb Oliver Francesca Pozzi Manfred Stickel Mattia Vaccari 《Monthly notices of the Royal Astronomical Society》2004,355(3):813-818
395.
C. Gruppioni F. Pozzi G. Zamorani P. Ciliegi C. Lari E. Calabrese F. La Franca I. Matute 《Monthly notices of the Royal Astronomical Society》2003,341(1):L1-L6
The radio counterparts to the 15-μm sources in the European Large Area ISO Survey southern fields are identified in 1.4-GHz maps down to ∼80 μJy. The radio–mid-infrared correlation is investigated and derived for the first time at these flux densities for a sample of this size. Our results show that radio and mid-infrared (MIR) luminosities correlate almost as well as radio and far-infrared (FIR), at least up to z ≃ 0.6 . Using the derived relation and its spread together with the observed 15-μm counts, we have estimated the expected contribution of the 15-μm extragalactic populations to the radio source counts and the role of MIR starburst galaxies in the well-known 1.4-GHz source excess observed at sub-mJy levels. Our analysis demonstrates that IR emitting starburst galaxies do not contribute significantly to the 1.4-GHz counts for strong sources, but start to become a significant fraction of the radio source population at flux densities ≲0.5–0.8 mJy. They are expected to be responsible for more than 60 per cent of the observed radio counts at ≲0.05 mJy. These results are in agreement with the existing results on optical identifications of faint radio sources. 相似文献
396.
V. D'Elia E. Branchini F. La Franca V. Baccetti I. Matute F. Pozzi C. Gruppioni 《Monthly notices of the Royal Astronomical Society》2005,359(3):1077-1082
We investigate the clustering properties of galaxies in the recently completed ELAIS-S1 redshift survey through their spatial two-point autocorrelation function. We used a subsample of the ELAIS-S1 catalogue covering approximately 4 deg2 and consisting of 148 objects selected at 15 μm with a flux >0.5 mJy and a redshift z < 0.5 . We detected a positive signal in the correlation function that in the range of separations 1–10 h −1 Mpc is well approximated by a power law with a slope γ= 1.4 ± 0.25 and a correlation length s 0 = 5.4 ± 1.2 h −1 Mpc , at the 90 per cent significance level. This result is in good agreement with the redshift-space correlation function measured in more local samples of mid-infrared-selected galaxies such as the IRAS Point Source Catalog (PSC z ) redshift survey. This suggests a lack of significant clustering evolution of infrared-selected objects out to z = 0.5 that is further confirmed by the consistency found between the correlation functions measured in a local ( z < 0.2) and a distant (0.2 < z < 0.5) subsample of ELAIS-S1 galaxies. We also confirm that optically selected galaxies in the local redshift surveys, especially those of the SDSS sample, are significantly more clustered than infrared objects. 相似文献
397.
One specimen ofPteraclis aesticola was collected off San José del Cabo, Baja California Sur, México (22°54′N, 109°45′W), in March 2007. Present record is the
first reported occurrence of the species in the Tropical Eastern Pacific biogeographic region (Gulf of California to southern
Ecuadorian waters). Its large fan-like anal and dorsal fins and its counts of fin rays and vertebrae can distinguish the Pacific
fanfish from the other species in the genus. This fish may have not yet been recorded in the region because its presence has
been overlooked in the past because of rarity and lack of commercial value. 相似文献
398.
399.
????2011???2013????????GPS?????????????????????????????????????о???????????????????????????????? ????????????????????????????????????????????????????????????????о???????2011??2013????????????????????????????????????????????????????-???????????λ????в??????????????????????λ??????????????????????????????2011??2013??????????????????NE55°????????????????????????????????С??????????????????????????????С???????????????????????????????????????????????????Ms??≥5.0????????2013???????????????????????????????-???л?????????5.8??????????????????????????????????????????? 相似文献
400.
Measurements of NH4, NO3, urea and HCO3 uptake using 15N and 13C stable isotope tracers were undertaken in Saldanha Bay, South Africa, between January 2012 and January 2013. These studies provide the first direct measurements of N utilisation by the plankton in the bay. Primary production in the bay is driven predominantly by the advection of nutrients from the neighbouring shelf environment during upwelling events, with terrestrial and other sources providing minor inputs. New production (NO3-based) was calculated from the f-ratio and total primary production and was used to provide estimates of potential carrying capacity for bivalve culture. Despite the apparent light limitation of NO3 uptake in the winter, the availability of NO3 appeared to exert the major influence on new production throughout the year. In addition, new production was modulated by NH4 availability as shown by the suppression of NO3 uptake by concentrations higher than 1?1.5?mmol m?3. The estimated areal new production of 0.60?g C m?2 d?1 yielded a bay-wide annual estimate of 9 811 t C ha?1 y?1, slightly higher than previous calculations based on physical models. It is estimated that the total annual production of mussels and oysters, respectively, for a 1 000-ha cultivation area is approximately 40 000–53 000 t y?1 (mainly Mytilus galloprovincialis) and 4 600–6 000 t y?1 (Crassotrea gigas). The combined total production figures constitute only 24–31% of the surplus new production. A combined harvestable carrying capacity of 74 000–82 000 t y?1 can be calculated from this surplus. However, from a management and ecological perspective, bivalve culture should be limited to well below this theoretical maximum. Even with this constraint, there appears to be considerable scope for expansion of bivalve farming over the modest, present levels with little jeopardy to ecological integrity. 相似文献