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91.
J. Chen  D. Liu  P. Peng  C. Yu  B. Zhang  Z. Xiao 《Geofluids》2013,13(3):381-394
The most important petroleum exploration target in the Tarim Basin, northwest China, is the paleokarst reservoir. To understand the source and evolution of brine in this type of reservoir, a total of 37 formation‐water samples were collected from the Middle‐Lower Ordovician paleokarst reservoir in the Lunnan oilfield. The δD‐δ18O correlation and Cl/Br ratios reflect the mixture of two fluids: meteoric water and evaporated seawater. The different degree of mixture divided samples into two groups. Group 1 samples, from deep strata (5150–6667 m.b.s.l.) in the east of the field, with elevated δD (?53.5 to ?38.0‰), δ18O values (0.66–5.99‰), and lower Cl/Br ratios (336–478 for Cl/Br, except LN634‐1 and LN631‐1) were formed by evaporation of seawater plus a small contribution from meteoric water. Group 2 samples, from shallow strata (5038–6067 m.b.s.l.), in the west of the field, have contrasting features (?59.6 to ?48.5‰ for δD, ?0.47 to 2.17‰ for δ18O, and 501 to 871 for Cl/Br), which reflect a mixture of evaporated seawater with a high proportion of meteoric water. Both of the fluid types exchanged oxygen isotope with minerals. The investigation into cation composition reveals that, before entering into the current reservoir, waters suffered albitization of plagioclase; moreover, meteoric water dissolved evaporites and seawater experienced dolomitization. A mixing trend showed by strontium isotopes (0.709801–0.711628) gave further evidence for the mixture of two fluid types. Based on the correlation of geological history with our data, two infiltration models of meteoric waters can be constructed. According to the chemical and isotopic compositions of the waters, an east fluid regime (Group 1) and a west fluid regime (Group 2) have thus been defined. Better understanding of the subsurface fluid movement patterns may be helpful for the local exploration.  相似文献   
92.
Meor, H.A.H., Yong, A.M., Zakaria, M.Z.Z. & Ghani, A.A., 2.6.2015. First record of Homoctenus (Tentaculitoidea, Homoctenida) from the Late Devonian of northwest Peninsular Malaysia. Alcheringa 39, 550–558. ISSN 0311-5518.

The homoctenid tentaculitoid genus Homoctenus is reported for the first time from Peninsular Malaysia. The fossils derive from the Upper Devonian Sanai Limestone, exposed in the state of Perlis, northwest Peninsular Malaysia. The fossils are closely related to Homoctenus tenuicinctus tenuicinctus and are described as Homoctenus sp. cf. H. tenuicinctus. The homoctenids were recovered from an interval containing a rich conodont assemblage, indicating a Frasnian age (Palmatolepis linguiformis Zone).

Meor Hakif Amir Hassan [], Yong Adilah Mustafa [], Mohamad Z.Z. Zakaria [], Azman A. Ghani [], Geology Department, University of Malaya, 50603 Kuala Lumpur, Malaysia. Received 12.4.2015; revised 27.5.2015; accepted 2.6.2015.  相似文献   
93.
A combined stochastic and Green's function approach was developed to simulate strong ground motions in Southwest Western Australia (SWWA) in a previous study. Although it was demonstrated that adopting the source parameters derived from other regions yielded reasonable simulation of ground motions in SWWA as compared with a few available strong motion records, the effect of source parameter variations on simulated ground motions was not known. This article performs a statistical study of the effects of random fluctuations of the seismic source parameters on simulated strong ground motions. The uncertain source parameters, i.e., stress drop ratio, rupture velocity, and rise time corresponding to the empirical source models are assumed to be the respective mean value of the parameter and normally distributed with an assumed coefficient of variation. The Rosenblueth's point estimate method [Rosenblueth, 1981 Rosenblueth, E. 1981. Two-point estimates in probabilities. Applied Mathematical Modelling, 5: 329335. [Crossref], [Web of Science ®] [Google Scholar]] is used to calculate the statistics of the simulate ground motion parameters corresponding to different magnitudes and epicentral distances. The accuracy of the Rosenblueth's point estimate method in estimating the mean and standard deviation of ground motion PGA, PGV, and response spectrum is proven by simulating the ground motions from an ML6.0 and epicentral distance 100 km event with both the Rosenblueth's point estimate method and the Monte Carlo simulation method. A sensitivity analysis is preformed to investigate the effect of random fluctuations of each source parameters on strong ground motion simulation. A coefficient of variation model for ground motion parameters is developed based on the simulated data as a function of the variations of the three source parameters and earthquake magnitude, which can be used in probabilistic predictions of earthquake ground motions with uncertain source parameters.  相似文献   
94.
Perth is the largest city in Western Australia and home to three-quarters of the state's residents. In recent decades, there have been a lot of earthquake activities just east of Perth in an area known as the South-West Seismic Zone. Previous numerical results of site response analyses based on limited available geology information for PMA indicated that Perth Basin might amplify the bedrock motion by more than 10 times at some frequencies and at some sites. Hence, more detailed studies on site characterization and amplification are necessary. The microtremor method using spatial autocorrelation (SPAC) processing is a useful tool for gaining thickness and shear wave velocity (SWV) of sediments and has been adopted in many previous studies. In this study, the response spectrum of rock site corresponding to the 475-year return period for PMA is defined according to the probabilistic seismic hazard analysis (PSHA) based on the latest ground motion attenuation model of Southwest Western Australia. Site characterization in PMA is performed using two microtremor measurements, namely SPAC technique and H/V method. The clonal selection algorithm (CSA) is introduced to perform direct inversion of SPAC curves to determine the soil profiles of representative PMA sites investigated in this study. Using the simulated bedrock motion as input, the responses of the soil sites are estimated using numerical method based on the shear-wave velocity vs. depth profiles determined from the SPAC technique. The response spectrum of the earthquake ground motion on surface of each site is derived from the numerical results of the site response analysis, and compared with the respective design spectrum defined in the Australian Earthquake Loading Code. The comparison shows that the code spectra are conservative in the short period range, but may slightly underestimate the response spectrum at some long period range.  相似文献   
95.
We present a paleopathological analysis of an adult male from the Bronze Age site of Motilla del Azuer (Daimiel, Ciudad Real) from the Spanish region of La Mancha. The hyoid bone from this individual exhibits a healed fracture. This is an exceptional archaeological find. This injury is extremely rare apart from hanging and strangulation, and it is even rarer since the individual survived this injury to his neck. This injury was probably produced by a direct impact to the neck. This event could have been the result of an accident or that of intentional aggression. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
96.
97.
Endocranial bone lesions have attracted intensive scientific debate on their aetiology. In recent literature, the lesions were almost exclusively interpreted as of infectious origin. In this paper, we give new insight into the aetiology of endocranial lesions, distinguishing the lesions of vascular origin from those caused by tuberculosis or other conditions. The analysis is based on a rare case of a young female individual who displayed multiple endocranial lesions with ‘serpens endocrania symmetrica’ morphology. The lesions were associated with an uncommon branching pattern of the middle meningeal artery and marked side differences in teeth pathology. Postcranial skeleton showed signs of the left upper limb weakness. The macroscopic finding of the endocranial lesions along with the skeletal evidence of neurological damage, together with characteristic radiological and histological features, can lead to diagnosis of arteriovenous malformations. This study aims to improve understanding of the aetiology of endocranial bone lesions. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
98.
Symbolic or incomplete trephinations are very common in Hungary in 9th–11thcentury AD skeletal series connected to early Hungarians, although they also occur in the preceding Avar Age (6th–9th c. AD) material. During the compilation of a database of regional cranial modification data, the authors found rare almond‐shaped symbolic trephinations in both periods, while these had formerly only been reported in Early Hungarian series. In this study, the new almond‐shaped lesions are described along with other symbolic trephinations of 14 newly found skulls from the 8th–11thcenturies AD in the Southern Great Plain of Hungary. The authors review the research of the phenomenon. The new findings may strengthen the theory of direct and very close cultural connections of these two ethnic groups, adding a new aspect to the debate over the origin and relationship of Late Avar (late 7th–early 9th c. AD) and Early Hungarian (9th–11th c. AD) populations. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
99.
The World Health Organization endorses the study of diseases from the perspective of the Determinants of Health (DH), that is, the circumstances in which people are born and raised, the environment in which they grow up and age and their lifestyle. The aim of this study is to analyze the spatial behavior of the prevalence of asthma in Aragon, a Mediterranean region in Spain, under the DH approach. The methodological process entailed building a spatial database collating asthma prevalence as dependent variable, and lifestyle, socioeconomic, and climate indicators as explanatory factors, and then evaluating the spatial variability of the relationships by combining the Principal Component Analysis (PCA), Multiscale Geographically Weighted Regression (MGWR) models and cartographic design techniques. MGWR evidenced spatially varying relationships operating at different scales. Lifestyles seem closely tied to the prevalence of asthma in most of the study area while urban functionality and local climate patterns seem to boost prevalence rates in some specific enclaves. Consequently, the social and environmental conditions that characterize the study area translate into several DH scenarios modulating the spatial distribution of asthma. This differential DH behavior detected by local regression models is relevant to guiding and refining public health decision-making.  相似文献   
100.
An Son in southern Vietnam is one of a series of Neolithic (food producing) settlement/cemetery sites in Southeast Asia that appear, archaeologically, shortly before and after 2000 cal. bc . Excavations in 2009 produced a small but important assemblage of vertebrate remains that permit relative comparisons with other zooarchaeological assemblages of similar date in Thailand and northern Vietnam. At An Son, domestic dogs are present from the earliest known phases of occupation with butchery evidence and a high proportion of canid remains, suggesting they were possibly used as a food resource. Suid bones were recovered from the earliest phases of the site excavated, and pig husbandry can be identified from at least 1800 to 1600 cal. bc . There is also evidence for the use of a range of other resources including fishing, hunting and the capturing of turtles. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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