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Summary An evaluation of the combination approach of Penman [1] as modified by Kohler and Parmele [2] for estimating potential evaporation (PE) is made at Poona, India, vis-a-vis the evaporation from the Russian 20 m2 tank and associated meteorological data. The use of Penman's form of wind function and net radiation computed from solar radiation, air temperature, and pyrgeometric value of sky radiation at 20.30 hrs. Indian Standard Time is seen to be adequate for obtaining reliable values of potential evaporation. Further lines of work to evaluate the potential evaporation climate over India are indicated.
Abschätzung der potentiellen Verdunstung durch kombinierte Annäherung
Zusammenfassung Eine Abschätzung der potentiellen Verdunstung (PE) wurde unter Benützung der Formel von Penman [1] mit der Abänderung von Kohler und Parmele [2] in Poona (Indien) durchgeführt und mit der Verdunstung von einer russischen 20m2-Wanne und gleichzeitigen meteorologischen Bedingungen verglichen. Die Benützung der Penman-Formel der Windabhängigkeit und der Strahlungsbilanz, berechnet aus Globalstrahlung, langwelliger Himmelsstrahlung und Lufttemperatur um 20.30 Uhr (indischer Lokalzeit) erweist sich als geeignet zur Gewinnung zuverlässiger Werte der potentiellen Verdunstung. Auf weitere Gesichtspunkte zur Bestimmung des potentiellen Verdunstungsklimas über Indien wird hingewiesen.

L'estimation de l'évaporation potentielle par combinaison approchée
Résumé L'évaluation du rapprochement de combinaison de Penman [1] telle qúelle est modifée par Kohler et Parmele [2] pour evaluér l'évaporation potentielle (PE) a étè employée à Poona, l'Inde, en comparaison avec l'évaporation de la citerne russe de 20 m2 et des données météorologiques supplémentaires. L'emploi de la formule de Penman de l'effet du vent et de la radiation nette calculée de la radiation solaire, de la température de l'air et de la valeur pyrgéométrique de la radiation du ciel à 20 heures 30 (heure indienne) se trouve être suffisant pour obtenir les valeurs sûres de l'évaporation potentielle. De plus, des directives du travail pour évaluer l'évaporation potentielle au-dessus de l'Inde sont discutées.
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The paper embodies the field, petrographic and petrochemical studies of the dykes occuring within the Deccan basalts, in the Western portions of Rajpipla hills. Major and minor dykes with different trends occur in the area varying in thickness from 2′ to 75′ and traceable lengthwise from few to several miles. The density of the dyke distribution is two per mile. The composition of the minor dykes ranges from teschenite to trachyte with dominant basaltic types and they seem to be coeval with the flows of the area. The major dolerite dykes are found to be post-lava. Both alkali-olivine basalt and tholeiitic types occur. The former phase preceeds the latter and includes the minor alkaline dykes. A differentiation trend based on new chemical analyses is proposed.  相似文献   
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Carbonate content and faunal composition of two gravity cores from the coastal Arabian sea provide evidence of a major environmental change in surface ocean waters about 13,000 yr B.P. Radiocarbon dating indicates that deposition rates ranged from 1.8 to 9.8 cm/103 yr, with a major change in rate occurring in one core at about 7500 yr B.P.  相似文献   
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A comprehensive set of measurements of oxygen and hydrogen isotopic ratios in groundwaters as well as waters from rivers, lakes, hot springs etc. taken from a variety of locations in India has been carried out for the first time. Isotopically the most depleted samples occur in the high altitude precipitations in the Himalayas e.g. in the lakes of Bhutan and the source water of the Ganga. The shallow groundwater data display a continental effect where the heavy isotope content decreases with distance from the coast (about 4 to 6 per mil decrease in δ18O per 1000 km). The δ D and δ18O of these fresh waters are linearly related and an analysis of this relation vis-a-vis the meteoric water line shows the unambiguous effect of enrichment due to evaporation from soils.  相似文献   
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Increasing groundwater salinity and depletion of the aquifers are major concerns in the UAE. Isotopes of oxygen, hydrogen, and carbon concentrations in groundwater were used to estimate evaporation loss using the isotopes of oxygen and hydrogen, and using a carbon isotope to trace inorganic carbon cycling in two main aquifers in the eastern part of the United Arab Emirates. The δD‐δ18O of groundwater samples plotted on a line given by: δD = 4 δ18O + 4 ·4 (r2 = 0·4). In comparison, the local meteoric water line (LMWL) has been defined by the line: δD = 8 δ18O + 15. In order to better understand the system investigated, samples were separated into two groups based on the δD‐δ18O relationship. These are (1) samples that plot above the LMWL (δD = 6·1 δ18O + 12·4, r2 = 0·8) and which are located predominantly in the north of the study area, and (2) samples that plot below the LMWL (δD = 5·6 δ18O + 6·2, r2 = 0·8) and which are mostly distributed in the south. Slopes for both the groups are similar and lower than that for LMWL indicating potential evaporation of recharging water. However, the y‐intercept, which differs between the two groups, suggests evaporation of return flow and evapotranspiration in the unsaturated zone to be more significant in the south. This is attributed to intense agricultural activities in the region. Samples from the eastern Gravel Plain aquifer have δ13C and dissolved inorganic carbon (DIC) values in the range from ? 10 to 17‰, and 12–100 mg C/l, respectively, while the range for those from the Ophiolite aquifer is from ? 11 to ? 16.4‰, and 16–114 mg C/l respectively. This suggests the control of C‐3 and C‐4 plants on DIC formation, an observation supported by the range δ13C of soil organic matter (from ? 18·5 to ? 22·1‰.) Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
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The leading empirical orthogonal function (EOF) of the June-Sept. mean, rotational horizontal wind at 850 hPa and 200 hPa (over the region 12.5°S–42.5°N, 50°E–100°E) from 56 years (1948–2003) of reanalysis (from the National Centers for Environmental Prediction) shows strong anti-cyclonic circulation at upper levels, strong Indian Ocean cross-equatorial flow and on-shore flow over western India at lower levels . The associated principal component (PC) is correlated at the 0.75 level with the seasonal mean observed Indian Monsoon rainfall (IMR). Composite differences of vertically integrated divergence (surface to 800 hPa) and vorticity (surface to 500 hPa) between ``strong' years (PC-1 exceeds one standard deviation σ) and ``weak' years (PC-1 less than − σ) suggest increased rising motion and storminess over the Bay of Bengal and central India. Composite difference maps of station rainfall from the India Meteorological Department (IMD) between strong years and normal years (weak years and normal years) are statistically significant over central India, with strong (weak) years associated with increased (decreased) precipitation. In both cases the maps of rainfall anomalies are of one sign throughout India. The correlation of PC-1 with global seasonal mean SST is strong and negative over the eastern equatorial Pacific, but positive in a surrounding horse-shoe like region. Significant negative correlation occurs in the northwestern Indian Ocean. The lag/lead correlation between the NINO3 SST index and PC-1 is similar to but stronger than the NINO3/IMR correlation. Modest (but significant) negative correlation is seen when NINO3 leads PC-1 (or IMR) by one-two months. Strong negative correlation is seen when PC-1 (or IMR) leads NINO3. The projections of running five-day means of horizontal rotational winds at 850 and 200 hPa onto EOF-1 (after removing the seasonal mean for each year) were pooled for strong, normal and weak years. The strong and normal year probability distribution functions (pdfs) are nearly indistinguishable, but the weak year pdf has more weight for moderate negative values and in both extreme tails and shows some hint of bi-modality.  相似文献   
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