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71.
Mature green tomato fruit (Lycopersicon esculentum Mill) of cv. Rutgers and the line Alcobaca-red were vacuum infiltrated with solutions of polyamines, their precursors and metabolites, and other compounds which might affect ripening and/or storage duration. Putrescine (1,4-diaminobutane), spermidine, spermine, diaminopropane, -aminobutyric acid and methionine were found to increase the storage life of these fruit after vacuum infiltration of the test compounds and storage of fruit in darkness. Polyamines probably play a role in the normal ripening/overripening process and may prove commercially valuable in the extension of fruit shelf life.The use of polyamines and related compounds in prolongation of the storage or shelf life of fruit is the subject of U.S. patent No. 4,957,757 (1990) awarded to the Cornell University Research Foundation.  相似文献   
72.
Eight new and one less known nematode species are described from Vöring Plateau at 970 m to 1426 m depth and adjacent deep-sea plain at 3062 m depth in the Norwegian Sea: Actinonema grafi sp. nov., Desmodora pilosa Ditlevsen, 1926, Leptolaimus meyer-reili sp. nov., Tarvaia heegeri sp. nov., Diplopeltoides linkei sp. nov., Diplopeltis bathmanni sp. nov., Southerniella nojii sp. nov, Pararaeolaimus rumohri sp. nov. and Theristus altenbachi sp. nov. Differential diagnoses to the eight new species are given. Actinonema grafi, Leptolaimus meyer-reili and Theristus altenbachi are frequently found on Vöring Plateau and belong to the most dominant species, whereas Desmodora pilosa and Pararaeolaimus rumohri are dominant species at few sites only. The other species occur sporadically, in few numbers, and belong — as do Pararaeolaimus rumohri — to seldomly reported nematode genera.Contribution No. 111 from Sonderforschungsbereich 313 der Universität Kiel, Germany.  相似文献   
73.
Synopsis During 22 daylight submersible dives in August 1979 numerous juvenile and adult tilefish, Lopholatilus chamaeleonticeps, were observed in and around vertical burrows in the clay substrate of portions of Hudson submarine canyon in depths from 110–230 m. The size and shape of the burrows varied considerably with the smallest juveniles occupying simple vertical shafts in the substrate. Larger fish were found in much larger burrows (up to 4–5 m in diameter and at least 2–3 m deep) that were funnel shaped in cross-section with the upper conical portions containing numerous smaller burrows of associated crabs. The range of burrow sizes observed suggests a regular sequence of burrow construction by tilefish and the associated crabs. Both juvenile and adult tilefish swam into the burrows head first and exited tail first. This behavior, which would preclude the possibility of ambushing prey, and evidence of predation by sharks and other tilefish, suggests that the burrow is a refuge from predators.Tilefish burrows appear to serve as a focus for biological activity. Species associated with the burrows included galatheid crabs, Cancer sp., Acanthocarpus alexandri, Homarus americanus, Heliocolenus dactylopterus and Conger oceanicus. Tilefish may play an important role in structuring outer continental shelf communities. They physically shape their environment and probably have significant biological interactions with the species that associate with their burrows.  相似文献   
74.
Two Lower Bajocian new localities, with many silicified bryozoans and brachiopods have been discovered in Causses (France): Saint-Rome-de-Cernon (Aveyron) and Mende (Lozère). The study of the faunas allows to increase the anterior knowledges supplied by the study of localities in the South of Causses (neighbourhood of Alzon and Sumène = North of the Seuil sud-caussenard).The interest is, at first, the distance between the localities: Mende in the North, Saint-Rome-de-Cernon in the West. Moreover, in the second, well-preserved faunas were fossilized without transport. Bryozoans and brachiopods are very numerous. Large and complete bryozoan colonies have been get out by action of HCl. Fine internal structures like rhynchonellid Nannirhynchia or like thecidean transversarium and hemispondylium have been studied. At last, observations and paleoecological hypothesis are drawn, likewise comparison between three localities or locality-groups known in the Causses basin.The fauna from Saint-Rome-de-Cernon is biocoenosis, the substratum was soft, the hydrodynamism low and the depth, according to lamellibranchs, about 200 meters. The beds with bryozoans and small brachiopods contain a fauna with two predominant bryozoan species: Ceriocava straminea and Mesenteripora wrighti. These two species could built large colonies, in spite of fine granulometry of the sedimentary bottom. These colonies provided supports to less adapted bryozoans, to thecidids and to lamellibranch Lopha. The beds with terebratulids and bryozoans contain lesser bryozoans and thecidids. Terebratulids are the main group and are fixed with their peduncle to organic support above the irregular deposits. Beside these benthic animals, the rhynchonellid Nannirhynchia campestriensis is epibiontic on gorgonids or epiphytic on floating sea-weeds.On the contrary, all fossils from Mende have been more or less carried, excepted large sponges perhaps. The most numerous bryozoans (Ceriocava straminea, Mesenteripora wrighti) and numerous Lenticulines (Foraminifera) lived on hard bottom with moving water in community with crinoids. It is possible that a smaller part of bryozoans, requiring lower hydrodynamism, lived, either in sheltered parts of the crinoid community or closer to the sedimentation zone. Thecidids were fixed either on bryozoans in crinoid communities or on shelly remains and on bryozoans nearer to the sedimentation zone. Like in Saint-Rome-de-Cernon, Nannirhynchia campestriensis was epibiontic, or epiphytic, or both.In comparison with the whole localities from the Seuil sud-caussenard, we notice the simplicity of Saint-Rome-de-Cernon and Mende. The localities from the Seuil sud-caussenard were assemblages proceeding from 2 or 3 biotops. On the contrary, at Saint-Rome-de-Cernon we have a biocoenosis and at Mende a thanatocoenosis supplied by one biotop almost.  相似文献   
75.
Varpe O  Fiksen O  Slotte A 《Oecologia》2005,146(3):443-451
Ecosystems are not closed, but receive resource subsidies from other ecosystems. Energy, material and organisms are moved between systems by physical vectors, but migrating animals also transport resources between systems. We report on large scale energy transport from ocean to coast by a migrating fish population, the Norwegian spring-spawning (NSS) herring Clupea harengus. We observe a rapid body mass increase during parts of the annual, oceanic feeding migration and we use a bioenergetics model to quantify energy consumption. The model predicts strong seasonal variation in food consumption with a marked peak in late May to July. The copepod Calanus finmarchicus is the most important prey and 23×106 tonnes (wet weight) of C. finmarchicus is consumed annually. The annual consumption-biomass ratio is 5.2. During the feeding migration 17% of consumed energy is converted to body mass. The biomass transported to the coast and left as reproductive output is estimated from gonad weight and is about 1.3×106 tonnes for the current population. This transport is to our knowledge the world’s largest flux of energy caused by a single population. We demonstrate marked temporal variation in transport during the last century and discuss the effects of NSS herring in the ocean, as a major consumer, and at the coast, where eggs and larvae are important for coastal predators. In particular, we suggest that the rapid decline of lobster Homarus gammarus landings in Western Norway during the 1960s was related to the collapse of NSS herring. We also discuss spatial variation in energy transport caused by changed migration patterns. Both climate and fisheries probably triggered historical changes in the migration patterns of NSS herring. New migration routes emerge at the level of individuals, which in turn determines where resources are gathered and delivered, and therefore, how meta-ecosystems function.  相似文献   
76.
A culture of a unicellular heterotrophic eukaryote was established from pollen‐baited seawater acquired from the nearshore environment in Tromsø, Norway. Light microscopy revealed the production of ectoplasmic nets and reproduction by biflagellated zoospores, as well as binary division. After culturing and subsequent nucleotide extraction, database queries of the isolate's 18S small ribosomal subunit coding region identified closest molecular affinity to Aplanochytrium haliotidis, a pathogen of abalone. Testing of phylogenetic hypotheses consistently grouped our unknown isolate and A. haliotidis among the homoplasious thraustochytrids. Transmission electron microscopy revealed complex cell walls comprised of electron‐dense lamella that formed protuberances, some associated with bothrosomes. Co‐culturing experiments with the marine fungus Penicillium brevicompactum revealed prolonged interactions with hyphal strands. Based on the combined information acquired from electron microscopy, life history information, and phylogenetic testing, we describe our unknown isolate as a novel species. To resolve molecular polyphyly within the aplanochytrids, we erect a gen. nov. that circumscribes our novel isolate and the former A. haliotidis within the thraustochytrids.  相似文献   
77.
Estimating denitrification in North Atlantic continental shelf sediments   总被引:17,自引:3,他引:14  
A model of coupled nitrification/denitrification was developed for continental shelf sediments to estimate the spatial distribution of denitrification throughout shelf regions in the North Atlantic basin. Using data from a wide range of continental shelf regions, we found a linear relationship between denitrification and sediment oxygen uptake. This relationship was applied to specific continental shelf regions by combining it with a second regression relating sediment oxygen uptake to primary production in the overlying water. The combined equation was: denitrification (mmol N m–2 d–1)=0.019* phytoplankton production (mmol C m–2 d–1). This relationship suggests that approximately 13% of the N incorporated into phytoplankton in shelf waters is eventually denitrified in the sediments via coupled nitrification/denitrification, assuming a C:N ratio of 6.625:1 for phytoplankton. The model calculated denitrification rates compare favorably with rates reported for several shelf regions in the North Atlantic.The model-predicted average denitrification rate for continental shelf sediments in the North Atlantic Basin is 0.69 mmol N m– 2 d–1. Denitrification rates (per unit area) predicted by the model are highest for the continental shelf region in the western North Atlantic between Cape Hatteras and South Florida and lowest for Hudson Bay, the Baffin Island region, and Greenland. Within latitudinal belts, average denitrification rates were lowest in the high latitudes, intermediate in the tropics and highest in the mid-latitudes. Although denitrification rates per unit area are lowest in the high latitudes, the total N removal by denitrification (53 × 1010 mol N y–1) is similar to that in the mid-latitudes (60 × 1010 mol N y–1) due to the large area of continental shelf in the high latitudes. The Gulf of St. Lawrence/Grand Banks area and the North Sea are responsible for seventy-five percent of the denitrification in the high latitude region. N removal by denitrification in the western North Atlantic (96 × 1010 mol N y–1) is two times greater than in the eastern North Atlantic (47 × 1010 mol N y–1). This is primarily due to differences in the area of continental shelf in the two regions, as the average denitrification rate per unit area is similar in the western and eastern North Atlantic.We calculate that a total of 143 × 1010 mol N y–1 is removed via coupled nitrification/denitrification on the North Atlantic continental shelf. This estimate is expected to underestimate total sediment denitrification because it does not include direct denitrification of nitrate from the overlying water. The rate of coupled nitrification/denitrification calculated is greater than the nitrogen inputs from atmospheric deposition and river sources combined, and suggests that onwelling of nutrient rich slope water is a major source of N for denitrification in shelf regions. For the two regions where N inputs to a shelf region from onwelling have been measured, onwelling appears to be able to balance the denitrification loss.  相似文献   
78.
Summary During the Late Eocene, shelf-edge patch reefs developed on the western margin of the Lessini Shelf. The coral fauna, studied in the Nago Limestone type locality, is described and interpreted for the first time, and provides further data for better understanding of the generally poorly known Eocene reef communities. Facies analysis was carried out across the shallowing upward succession that characterizes the well exposed type-section of the Nago Limestone. Four distinct facies are identified and a detailed qualitative-quantitative investigation has been applied to the coral-bearing facies in particular, in order to describe and quantify the distribution and palaeoecological zonation of corals. By a comparison of sedimentological and palaeoecological data, it is possible to reconstruct a depositional model of the Nago Limestone at its type locality. In particular, the palaeoecological study clearly reveals that corals change with depth in taxonomic composition, in percentage and proportion within the framework and in growth form, allowing the definition of a relative depth coral zonation. Three coral associations are recognized from the base to the top of the shallowing upward sequence. These differ from each other in the relative abundance of main reefbuilders, in the growth form exhibited by corals in growth position and in the density of the reef framework. These variations are interpreted as responses to major environmental controls which prevailed during the deposition of the different facies (mainly light intensity and hydrodynamic energy). The coral speciesActinacis rollei Reuss is the most abundant and ubiquitous coral of the Nago Limestone. Its adaptation to low-light levels is described here for the first time, confirming the high plasticity of this important Paleogene reef-builder. The results of the present study are finally compared with data from other Middle-Late Eocene European reef sites and some common features are inferred.  相似文献   
79.
Spring-spawning herring Clupea harengus was patchily distributed over large parts of the Norwegian Sea in May 1995–2005, during the early phase of the annual feeding migration. Overall, herring tended to be found in areas with intermediate biomasses of zooplankton prey, intermediate water temperatures and relatively high salinities. Herring had more food in their stomachs in areas of relatively low water temperature and high herring abundance. Hydrographical conditions revealed that herring was feeding mainly within Atlantic water masses, and more intensely in western and northern regions of the Norwegian Sea. Zooplankton biomass was patchily distributed, and was generally higher towards the western parts of the Norwegian Sea. Here, zooplankton biomass in year i +1 was also negatively associated with herring spawning stock biomass in year i , while there was no evidence for such an association in the eastern region; indicating that herring may have a geographically structured 'top–down' effect on the recruitment of its zooplankton prey. The fact that herring was not typically associated with the areas containing the greatest zooplankton biomasses may reflect that the fish had not yet reached the most profitable feeding grounds or alternatively that herring was depleting zooplankton biomass.  相似文献   
80.
In the 2017 Maritime Delimitation in the Indian Ocean Case, the International Court of Justice stated that “in appropriate circumstances” maritime delimitation claims beyond 200 nm may be admitted before the Commission on the Limits of the Continental Shelf issues a recommendation. This is a deviation from the Court's previous approach in the 2016 Nicaragua v. Colombia (Preliminary Objections) Case. This article follows the evolution of the international case law with respect to the admissibility of outer continental shelf delimitation claims absent a final and binding outer limit, and highlights the positive implications of the International Court's most recent formula.  相似文献   
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