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91.
The copepod community on the Faroe shelf is dominated by Calanus finmarchicus, Temora longicornis, Acartia longiremis and Pseudocalanus spp. The species composition, abundance and development of the copepod community varied considerably during the season 2004. These variations reflected to a large extent the different life strategies of the copepods. Both nauplii and copepodites of C. finmarchicus were most abundant during spring and early summer. The two neritic copepods T. longicornis and A. longiremis were present in low numbers during spring but dominated the copepod community later during the productive period. Pseudocalanus spp., on the other hand, occurred throughout the year, but showed no clear numerical response in abundance to the spring bloom. The egg production measurements of C. finmarchicus and T. longicornis showed some pre-bloom egg production, but as the spring bloom started the egg production rate increased significantly, especially for C. finmarchicus. There seemed to be a substantial loss of nauplii and copepods from the shelf ecosystem during the productive season. It was, however, not possible to determine whether this was mainly due to mortality or advective loss.  相似文献   
92.
Finishing late-maturing bulls on grass may alter the antioxidant/prooxidant balance leading to beef with higher susceptibility to lipid oxidation and a lower colour stability compared to bulls finished on cereal concentrates. In this context, lipid oxidation and colour stability of beef from late-maturing bulls finished on pasture, with or without concentrate supplements, or indoors on concentrate was assessed. Charolais or Limousin sired bulls (n = 48) were assigned to four production systems: (1) pasture only (P), (2) pasture plus 25% dietary DM intake as barley-based concentrate (PC25), (3) pasture plus 50% dietary DM intake as barley-based concentrate (PC50) or (4) a barley-based concentrate ration (C). Following slaughter and postmortem ageing, M. Longissimus thoracis et lumborum was subjected to simulated retail display (4°C, 1000 lux for 12 h out of 24 h) for 3, 7, 10 and 14 days in modified atmosphere packs (O2 : CO2; 80 : 20). Lipid oxidation was determined using the 2-thiobarbituric acid-reactive substances assay; α-tocopherol was determined by HPLC; fatty acid methyl esters were determined using Gas Chromatography. Using a randomised complete block design, treatment means were compared by either ANOVA or repeated measures ANOVA using the MIXED procedure of SAS. Total polyunsaturated fatty acid (PUFA) concentrations were not affected by treatment, n-3 PUFAs were higher (P < 0.001) and the ratio of n-6 to n-3 PUFAs was lower (P < 0.001) in muscle from P, PC25 and PC50 compared to C. α-Tocopherol concentration was higher in muscle from P compared to PC50 and C bulls (P = 0.001) and decreased (P < 0.001) in all samples by day 14. Lipid oxidation was higher in muscle from C compared to P bulls on day 10 and day 14 of storage (P < 0.01). Finishing on pasture without supplementation did not affect beef colour stability and led to lower lipid oxidation, possibly due to the higher α-tocopherol concentration compared to concentrate finished beef.  相似文献   
93.
Abstract

Delimitation of maritime boundaries represents a recent state activity. The main impetus stems from the 1958 Geneva Conventions on the Territorial Sea … and on the Continental Shelf. State practice since 1958 has shown a marked preference for the equidistance principle for maritime boundary delimitation. At first many of these limits were geometrically constructed on existing nautical charts or on specifically designed small‐to medium‐scale maps. With increasing ability to exploit marine resources and the associated need to delimit boundaries farther from the baseline, inequities have developed as a consequence of map projections utilized, differences in horizontal and vertical datums, and so on. This paper discusses the principles behind, and the development of, conventional techniques of equidistant boundary delimitation; illustrates the errors that may result; and points out means, through modern computer technology, to compute equitable, equidistant maritime boundaries at great distances from the baselines.  相似文献   
94.
The International Tribunal on the Law of the Sea's March 2012 Judgment in the Bay of Bengal Case is a landmark decision in multiple ways. It represents the first maritime boundary to be delimitated by the Tribunal. It is the first adjudication of a maritime boundary in Asia, and it is also the first judicial delimitation of a maritime boundary for parts of the extended continental shelf located seaward of the 200-nautical-mile limit from baselines. While the Tribunal's ruling largely resolves the maritime dispute between Bangladesh and Myanmar, it also raises a number of questions and concerns that are highlighted in this article, including the Tribunal's approach to delimitation both within and beyond the 200-nautical-mile limit, the treatment of islands, the interplay between law of the sea institutions and the creation of a so-called grey area where continental shelf jurisdiction falls to one state and water column jurisdiction to the other.  相似文献   
95.
96.
Aims: The aim of this study was to update and extend our knowledge of the bacterial load and microbial composition in Norway lobster (Nephrops norvegicus) under commercially relevant storage conditions to optimize handling procedures. Methods and Results: Total viable counts were performed at different storage temperatures (0, 4, 8, 10, 12 or 16°C) and after different storage times (1–7 days). Storage at 16°C was found to be most detrimental, and storage at 0°C was found to be optimal. 16S‐rRNA sequencing was utilized to determine the composition of the bacteria within the microflora. In this way, Photobacterium isolates, especially Photobacterium phosphoreum, were identified as the main specific spoilage organisms. The abilities to reduce trimethylamineoxide (TMAO) and to produce H2S were analysed in a selection of bacterial isolates. The higher the incubation temperature during storage, the more isolates were found to reduce TMAO and produce H2S. Conclusions: Nephrops norvegicus possesses an unusually high initial microbial load when fresh. Storage temperature is the most crucial factor affecting microbial growth, microbial activity and spoilage potential in N. norvegicus produce. Spoilage can be attributed mainly to P. phosphoreum. Significance and Impact of the Study: This study presents significant new findings with regard to the progression and causative agents of spoilage in N. norvegicus. Based on the results, we can recommend that N. norvegicus tails should be stored in a 0°C environment immediately after catch. Stored this way, the growth and spoilage activity of the microflora may be reduced significantly and an extension of shelf life might be attained.  相似文献   
97.
A survey described genetically encoded enzyme variation in 197 adult Argentinian hake, Merhccius hubhsi , collected from 10 sample sites on the Argentinian continental shelf. Four of 11 muscle enzyme loci were polymorphic ( PCM *, G3PDH *, EST-1 * and EST-2 *). Genotypes showed no significant difference between males and females. Only one of 37 tests of departure from Hardy-Weinberg equilibrium showed a significant difference. The allele frequency data were tested for genetic heterogeneity among locations. The overall significance of the total samples and among those from Patagonia Central was primarily due to heterogeneity at the EST-1 * locus. The implications of these findings in a population structure context are discussed.  相似文献   
98.
Six samples collected from the eastern Brazilian continental shelf, along the states of Bahia and Espírito Santo, during the REVIZEE Program were analysed. Three species of Macrocyprina were encountered in these samples. Macrocyprina maddocksae sp. nov. is described. This species is diagnosed by the following combined characteristics: carapace fairly small, its lateral surface with three or four small subcircular patches, one small, subtriangular patch at anteroventral margin, one small, elongate, patch at posteroventral margin; male appendages V strongly asymmetrical, left appendage larger than right, podomere II of left appendage subtriangular, not recurved. Hemipenis subtrapezoidal. Furthermore, M. sp. nov. 3 Brandão, in press and M. sp. are recorded.  相似文献   
99.
The frequency and distribution of high biomass blooms produced by two dinoflagellate species were analysed along the French continental shelf from 1998 to 2012. Two species were specifically studied: Karenia mikimotoi and Lepidodinium chlorophorum. Based on remote-sensing reflectances at six channels (410, 430, 480, 530, 550 and 670 nm), satellite indices were created to discriminate the species forming the blooms. A comparison with observations showed that the identification was good for both species in spite of a lower specificity for L. chlorophorum. The overall analysis of the satellite indices, in association with some monitoring data and cruise observations, highlights the regularity of these events and their extent on the continental shelf. L. chlorophorum blooms may occur all along the South Coast of Brittany. All the coastal areas under the influence of river plumes and the stratified northern shelf area of the Western English Channel appear to be areas of bloom events for both species. These two species are likely to be in competitive exclusion as they share the same spatial distribution and the timing of their bloom is very close. Finally, due to the scarcity of off-shore observations, these satellite indices provide useful information regarding HABs management and the development of a warning system along the French coast.  相似文献   
100.
The feeding ecology of the larvae of silver hake Merluccius bilinearis was examined during two time periods (October 1998 and December 1992) on the Western Bank, Scotian Shelf, north‐west Atlantic, and compared with the feeding ecology of Atlantic cod Gadus morhua larvae collected in the same samples in December 1992. During both time periods silver hake exhibited strong selection for late stage copepodids and adult copepods at a small size (>3·5 mm total length, L T). The niche width measured as the diet breadth index ( I DB) of silver hake declined rapidly as they increased in size and remained relatively constant from 3 to 11 mm L T, during each time period. Atlantic cod larvae exhibited a broader niche width that was curvilinear over the same L T. Atlantic cod were also less selective than silver hake, incorporating both naupliar and early stage copepodids in their diets throughout the length classes examined. Simple isometric relationships did not explain the differences in diet, as Atlantic cod larvae continued to feed on early stages of copepods at large size, while silver hake larvae quickly switched to large prey items. The strong selection and narrow I DB observed for silver hake probably reflects adaptation to spawning during the periods between major secondary production peaks in temperate waters.  相似文献   
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