全文获取类型
收费全文 | 113篇 |
免费 | 1篇 |
国内免费 | 3篇 |
专业分类
测绘学 | 3篇 |
大气科学 | 7篇 |
地球物理 | 30篇 |
地质学 | 53篇 |
海洋学 | 2篇 |
天文学 | 13篇 |
综合类 | 2篇 |
自然地理 | 7篇 |
出版年
2022年 | 4篇 |
2021年 | 3篇 |
2020年 | 3篇 |
2019年 | 2篇 |
2018年 | 12篇 |
2017年 | 8篇 |
2016年 | 8篇 |
2015年 | 5篇 |
2014年 | 5篇 |
2013年 | 14篇 |
2012年 | 11篇 |
2011年 | 8篇 |
2010年 | 3篇 |
2009年 | 3篇 |
2008年 | 3篇 |
2007年 | 2篇 |
2006年 | 3篇 |
2005年 | 1篇 |
2004年 | 1篇 |
2003年 | 1篇 |
2001年 | 1篇 |
2000年 | 1篇 |
1999年 | 2篇 |
1998年 | 3篇 |
1992年 | 1篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1977年 | 1篇 |
1976年 | 1篇 |
1975年 | 1篇 |
1974年 | 3篇 |
排序方式: 共有117条查询结果,搜索用时 15 毫秒
1.
Laurentiu Danciu Karin Şeşetyan Mine Demircioglu Levent Gülen Mehdi Zare Roberto Basili Ata Elias Shota Adamia Nino Tsereteli Hilal Yalçın Murat Utkucu Muhammad Asif Khan Mohammad Sayab Khaled Hessami Andrea N. Rovida Massimiliano Stucchi Jean-Pierre Burg Arkady Karakhanian Hektor Babayan Mher Avanesyan Tahir Mammadli Mahmood Al-Qaryouti Doğan Kalafat Otar Varazanashvili Mustafa Erdik Domenico Giardini 《Bulletin of Earthquake Engineering》2018,16(8):3465-3496
2.
Abbasi Faezeh Bazgeer Saeed Kalehbasti Parviz Rezazadeh Oskoue Ebrahim Asadi Haghighat Masoud Kalehbasti Pouya Rezazadeh 《Theoretical and Applied Climatology》2022,147(1-2):47-61
Theoretical and Applied Climatology - Recently in agricultural and industrial sectors, researchers have started to classify the climate of a region using empirical methods and clustering. This... 相似文献
3.
Thirty percent of present industrial water consumption of the Golgohar Iron Ore Mine (GIOM) is supplied from a hard rock well (PW-A15) and the rest from 25 wells located in 4 disconnected alluvial aquifers. This well is drilled in the metamorphic complex of Golgohar formation. Attempts have been made to develop extraction of water from other hard rocks existing in the area with no success. Therefore, extensive researches have been carried out to find the pathway, or a provision pathway of water discharged from this well. To study the hydrochemical similarity of this water with other water resources, 122 water samples from an area of 7132 km2 were collected from the existing pumping wells, piezometers, mine exploration bore holes, and three salt pans in the vicinity of the area for hydrochemical analysis. The analyses were performed for concentration of major ions and some minor elements. Furthermore, the spatial distribution of ion concentration was plotted in the GIS to delineate the similarity of the PW-A15 water with other water sources and their hydrochemical neighborhood by analytical hierarchy process (AHP). The AHP was performed in two steps: first, iso-concentration maps of seven major ions, eight minor elements, and TDS were used to produce an AHP map (Map1) using weights for different hydrochemical parameters; and second, a similarity index (SI) map was prepared by performing a suggested clustering approach in SPSS using K-means clustering, which was overlaid on Map1 producing Map2. The result of AHP Map2 was then overlaid on the iso-potential map of the sampled locations in GIS software using a mask operator. Therefore, the zones having the most similarity and higher hydraulic potential than PW-A15 were nominated as the zones which possibly could recharge this well, and the groundwater (GW) pathway was proposed. The result of the study method showed to be successful and will be used as a guide for future exploration drillings. 相似文献
4.
5.
Malachite green (MG), a traditional agent used in aquaculture although is not approved; its low cost and high efficacy make illicit use likely. We developed a small‐scale, simple, and sensitive dispersive liquid–liquid microextraction procedure for the assay of trace amounts of MG in aquatic environment of Trout fish. Fiber optic‐linear array detection spectrophotometry with charge‐coupled device detector benefiting from a microcell was used for this purpose. The method is based on enhancement effect of an anionic surfactant on the extraction of MG in to very fine multidroplets of microextraction solvent which made assisted by disperser solvent. Under the optimum conditions, the enrichment factor 77.5 was obtained from a 5‐mL water sample. The calibration graph was linear up to 5 × 10?7 mol L?1 with detection limit of 1 × 10?8 mol L?1. The relative standard deviation for seven replicate measurements of 4 × 10?7 and 5 × 10?8 mol L?1 of MG were 3.3 and 4.5%, respectively. 相似文献
6.
Natural Hazards - This paper has classified nine attenuation laws derived for subduction interface earthquakes through a comparative study based on the peak ground accelerations (PGAs) recorded in... 相似文献
7.
In the present study, some biological traits of Caridina fossarum reproduction are studied in the Ghomp-Atashkedeh spring (Fasa, Shiraz, Iran), for the first time. This Iranian endemic freshwater species was studied from April 2007 to March 2008. Minimum sexable size (MSS) and absolute or relative size at the onset of maturity (SOM and RSOM) in terms of carapace length (CL) was found to be 2.4 mm, 4.3 mm and 55%, respectively. Sex ratio showed variations on a monthly basis. Sex reversal is a possible scenario for C. fossarum because the size-specific sex ratio revealed a reverse pattern. Based on the proportions of ovigerous females, the main breeding season was determined to be from April to August, demonstrating a peak during early spring. There is a period of extended recruitment at water temperatures above 20 °C. The size at which 50% of females are mature was estimated at CL = 5.03 mm from the proportion of ovigerous females during the breeding season. The pleopodal egg number varied from 3 to 75 eggs per female with a mean value 34.39 ± 14.27. The results showed that although there is a significant relationship between carapace length CL and pleopodal egg number, it is not the most important factor affecting potential fecundity in C. fossarum due to the low values of slope (= 1.51) and determination coefficient (= 0.052). 相似文献
8.
Recent developments of the Middle East catalog 总被引:8,自引:2,他引:6
Mehdi Zare Hamideh Amini Pouye Yazdi Karin Sesetyan Mine Betul Demircioglu Dogan Kalafat Mustafa Erdik Domenico Giardini M. Asif Khan Nino Tsereteli 《Journal of Seismology》2014,18(4):749-772
This article summarizes a recent study in the framework of the Global Earth model (GEM) and the Earthquake Model of the Middle East (EMME) project to establish the new catalog of seismicity for the Middle East, using all historical (pre-1900), early and modern instrumental events up to 2006. According to different seismicity, which depends on geophysical, geological, tectonic, and seismicity data, this region is subdivided to nine subregions, consisting of Alborz–Azerbaijan, Afghanistan–Pakistan, Saudi Arabia, Caucasus, Central Iran, Kopeh–Dagh, Makran, Zagros, and Turkey (Eastern Anatolia; after 30° E). After omitting the duplicate events, aftershocks, and foreshocks by using the Gruenthal method, and uniform all magnitude to Mw scale, 28,244 main events remain for the new catalog of Middle East from 1250 B.C. through 2006. The magnitude of completeness (Mc) was determined as 4.9 for five out of nine subregions, where the least values of Mc were found to be 4.2. The threshold of Mc is around 5.5, 5.0, 4.5, and 4.0, for the time after 1950, 1963, 1975, and 2000, respectively. The average of teleseismic depths in all regions is less than 15 km. Totally, majority of depth for Kopeh–Dagh and Central Iran, Zagros, and Alborz–Azerbaijan, approximately, is 15, 13, and 11 km and for Afghanistan–Pakistan, Caucasus, Makran, Turkey (after 30° E), and Saudi Arabia is about 9 km. 相似文献
9.
Jií Bruthans Michal Filippi Naser Asadi Mohammad Zare Stanislav lechta Zdenka Chur
kov 《Geomorphology》2009,107(3-4):195-209
The surfaces of salt diapirs in the Zagros Mountains are mostly covered by surficial deposits, which significantly affect erosion rates, salt karst evolution, land use and the density of the vegetation cover. Eleven salt diapirs were selected for the study of surficial deposits in order to cover variability in the geology, morphology and climate in a majority of the diapirs in the Zagros Mountains and Persian Gulf Platform. The chemical and mineralogical compositions of 80 selected samples were studied mainly by X-ray powder diffraction and X-ray fluorescence. Changes in salinity along selected vertical profiles were studied together with the halite and gypsum distribution. The subaerial residuum formed from minerals and rock detritus released from the dissolved rock salt is by far the most abundant material on the diapirs. Fluvial sediments derived from this type of residuum are the second most common deposits found, while submarine residuum and marine sediments have only local importance. The mineralogical/chemical composition of surficial deposits varies amongst the three end members: evaporite minerals (gypsum/anhydrite and minor halite), carbonates (dolomite and calcite) and silicates-oxides (mainly quartz, phyllosilicates, and hematite). Based on infiltration tests on different types of surficial deposits, most of the rainwater will infiltrate, while overland flow predominates on rock salt exposures. Recharge concentration and thick accumulations of fine sediment support relatively rich vegetation cover in some places and even enable local agricultural activity. The source material, diapir relief, climatic conditions and vegetation cover were found to be the main factors affecting the development and erosion of surficial deposits. A difference was found in residuum type and landscape morphology between the relatively humid NW part of the studied area and the arid Persian Gulf coast: In the NW, the medium and thick residuum seems to be stable under current climatic conditions. Large sinkholes and blind valleys with sinking streams are common. On other diapirs, the original thick residuum is undergoing erosion and the new morphology is currently represented by salt exposures and badland-like landscapes or by fields of small sinkholes developed in the thin residuum. Models for evolution of the subaerial residuum and the diapir landscape/morphology are described in this paper. While the thick residuum with vegetation has very low erosion rates, the salt exposures and thin residuum are eroded rapidly. During wet periods (e.g. early Holocene), the diapirs rose and salt glaciers expanded as the influx of salt mass was much faster compared to erosion. After the onset of an arid climate, c. 6 ka BP, the rising of the some diapir surfaces decreased or even reversed due to acceleration of erosion thanks to vegetation degradation and changes in the residuum type and thickness. 相似文献
10.
Investigating effects of land use change scenarios on soil erosion using CLUE-s and RUSLE models 总被引:1,自引:0,他引:1
M. Zare A. A. Nazari Samani M. Mohammady H. Salmani J. Bazrafshan 《International Journal of Environmental Science and Technology》2017,14(9):1905-1918
Predicting soil erosion change is an important strategy in watershed management. The objective of this research was to evaluate land use change effects on soil erosion in the north of Iran using five land use scenarios. Three land use maps were created for a period of 25 years (1986–2010) to investigate land use transition and to simulate land use for the year 2030. Additionally, the RUSLE model was used to estimate erosion and the effect of land use change. The results showed that CLUE-s is suitable for modeling future land use transition using ROC curve. The median soil loss in the basis period was 104.52 t ha?1 years?1. Results indicate that the range of soil loss change is 2–32% in simulated period and soil loss value was higher than basis period in all scenarios. Thirty percent decrease in demand scenario has the lowest soil loss in simulated period, and the soil loss value under this scenario will be only 2% more than the basis period. Thus, the soil conversion effects resulted from the demand of each land use. 相似文献