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1.
The phospholipid fatty acid composition of the Calcarean spongeLeucosolenia canariensis was studied, and no Δ5,9 fatty acids were detected. These results are in contrast to the phospholipids from sponges belonging to the class Demospongiae
where Δ5,9 fatty acids are predominant. Odd branched-chain fatty acids between 17 and 19 carbons accounted for 26% of the
total fatty acids ofL. canariensis, while straight-chain fatty acids between 16 and 22 carbons accounted for 61% of the total fatty acid composition. The sterol
composition ofL. canariensis is also reported, and only Δ5,7,22 sterols were observed. 相似文献
2.
The phospholipid fatty acid composition of the Caribbean sponge Erylus goffrilleri is described for the first time. A total of 70 fatty acids with chain lengths between 13 and 29 carbons were identified in
the sponge. Methyl-branched fatty acids predominated in E. goffrilleri suggesting the presence of a considerable number of bacterial symbionts. The novel fatty acids (5Z,9Z)-2-methoxy-5,9-hexadecadienoic acid, (5Z,9Z)-2-methoxy-5,9-octadecadienoic acid, (5Z,9Z)-2-methoxy-5,9-nonadecadienoic acid, and (5Z,9Z)-2-methoxy-5,9-eicosadienoic acid are described for the first time in the literature. In addition, the iso-methyl-branched fatty acids (9Z)-2-methoxy-15-methyl-9-hexadecenoic acid and (5Z,9Z)-2-methoxy-15-methyl-5,9-hexadecadienoic acid, also identified in E. goffrilleri, were identified for the first time in nature. Based on the identified metabolites it is proposed that the unprecedented
biosynthetic sequence: i-17:1Δ9 → 2-OMe-i-17:1Δ9 → 2-OMe-i-17:2Δ5,9 might be responsible for the biosynthesis of the novel iso-α-methoxylated fatty acids in E. goffrilleri. 相似文献
3.
Néstor M. Carballeira Fathi Shalabi Kamen Stefanov Krassimir Dimitrov Simeon Popov Athanas Kujumgiev Stoitze Andreev 《Lipids》1995,30(7):677-679
The fatty acid composition of the tunicateBotryllus schlosseri and of two bacterial strains found within the tunicate, namelyVibrio parahaemolyticus and of an associated but previously unreported gram positive cocci were studied. The polyunsaturated fatty acids 6,9,12-octadecatrienoic
acid, 5,8,11,14,17-eicosapentaenoic acid, and 4,7,10,13,16,19-docosahexaenoic acid were particularly abundant inB. schlosseri and were not detected in the two bacterial strains found in the tunicate. Theiso/anteiso pair, 13-methyltetradecanoic acid and 12-methyltetradecanoic acid, were the principal fatty acids in the gram positive cocci,
and the 9- and 11-hexadecenoic acids were particulary abundant inV. parahaemolyticus. The diunsaturated fatty acid 9,12-octadecadienoic acid was also shown to be present inV. parahaemolyticus. The fatty acid composition of a third bacterial strain, characterized as either aPseudomonas or anAlteromonas species, and shown to be present only in the sea water from the Black Sea and not inB. schlosseri, is also reported. This is the first investigation on fatty acids from Black Sea bacteria. 相似文献
4.
Villares R Real C Fernández JA Aboal J Carballeira A 《The Science of the total environment》2007,374(2-3):379-387
In the present study we investigated possible contamination by trace elements due to the oil slick caused by the shipwreck of the Prestige oil tanker, in two species of brown macroalgae (Fucus vesiculosus and Fucus ceranoides) collected from the coastal area most severely affected by the spill (Galicia, NW Spain). The oil slick apparently did not cause significant increases in the concentrations of the trace elements studied, except vanadium. It appears that the magnitude of terrestrial inputs to coastal waters is sufficiently high to mask the inputs of trace elements from the fuel. The observed exception of V suggests that bioaccumulation of this element by the two species of Fucus may be used to indicate exposure to petrochemical products similar to the Prestige fuel. The findings of the study are another example of the importance of the existence of Environmental Specimen Banks for studies of this type. 相似文献
5.
Different European Framework Directives have established a series of objectives for conservation of the coast, and monitoring tools must be made available to test compliance with these aims. In the present study the use of macroalgae deposited in an Environmental Specimen Bank was evaluated as a possible environmental tool for monitoring the coastal ecosystem. The concentrations of Al, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, V and Zn in three species of the genus Fucus (Fucus spiralis, Fucus vesiculosus and Fucus ceranoides) were measured at sampling sites distributed along the coast of Galicia (NW Spain). In the period 1990-2001, the concentrations of the metals were higher in 1990 than in 2001, with the exception of: i) Mn in F. ceranoides and Fe in F. spiralis-F. vesiculosus, for which there were no differences between the sampling periods, and ii) Zn in F. vesiculosus and Fe in F. ceranoides, for which the concentrations were higher in 2001 than in 1990. In the period 2001-2007 concentrations of the metals were more stable, especially in F. ceranoides (e.g. Al, Fe, Hg, Ni and V). The concentrations were also more stable vin F. vesiculosus in 2005 (i.e. Al, Cr, Fe, Mn and Zn). The population density distributions are consistent with the results of the statistical tests. The results indicate that macroalgae of the genus Fucus may be useful for applying different European Framework Directives, given that the macroalgae are sufficiently sensitive to changes in concentrations of metals, and may be suitable for long-term monitoring and used for the detection of increased concentrations of metals (real-time monitoring). 相似文献
6.
Vázquez MD Fernández JA Real C Villares R Aboal JR Carballeira A 《The Science of the total environment》2007,388(1-3):357-371
The aim of the present study was to establish an aquatic biomonitoring network for the Galician Environmental Specimen Bank (BEAG) (NW Spain). For this, a sampling system was designed that comprised of 121 points distributed throughout Galician rivers, from which samples of water and of three species of bryophytes were collected. The results obtained allowed selection of 74 sampling points and 2 species (Fontinalis antipyretica Hedw. and F. squamosa Hedw.) as the most suitable for use in future BEAG sampling surveys. The two species selected showed a strong similarity in their capacity to accumulate the 17 elements determined (Al, As, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Mg, Mn, Na, Ni, Pb, Se and Zn), as well as in their ecological preferences. Furthermore, the levels of contamination of epicontinental waters were lower than those observed in previous surveys. 相似文献
7.
Use of native and transplanted mosses as complementary techniques for biomonitoring mercury around an industrial facility 总被引:1,自引:0,他引:1
Terrestrial mosses were used simultaneously in passive (native species, Scleropodium purum and Hypnum cupressiforme) and active (S. purum transplants in moss bags) biomonitoring techniques in a study that aimed to demonstrate the compatibility of the two methods by detailed investigation of the spatial distribution of mercury in the surroundings of a chlor-alkali plant. Native mosses were sampled and transplants exposed (for periods of 30 days) at two different times of the year in order to take into account different environmental conditions (precipitation, temperature, prevailing winds, etc.). The concentrations of Hg in the native mosses ranged between 0.04 and 11.78 microg g(-1) in February and 0.26 and 12.7 microg g(-1) in September; in the transplants the concentrations ranged between 0.39 and 1.9 microg g(-1) in June and 0.036 and 2.75 microg g(-1) in November. These values are all within the ranges reported in the literature. The total concentrations were transformed into either contamination factors (CF) (by taking into account the background levels of Hg in the native mosses) or enrichment factors (EF) (by taking into account the initial concentrations in the transplants). In both cases, there was a clear relationship with the distance from the source of emission, irrespective of the time of year. Within the range of distances for which data were available for natives and transplants, the CF and EF were highly correlated. This implies that transplants sited in the area immediately surrounding the plant, where the density of native mosses was very low, can be used to determine the degree of contamination in this area. The study also illustrated that the native moss appeared to adapt to the surrounding environment because at an equal distance (> 500 m) from the source of emission the value of the CF for native mosses fell to 1, but the EF for transplanted mosses remained still high (5.2). 相似文献
8.
The phospholipid fatty acids from the spongeSpheciospongia cuspidifera were studied revealing the presence of the rare 10-octadecenoic acid (10−18∶1) and a new 2-methoxyhexadecenoic acid. The
phospholipid fatty acids fromThalysias juniperina were also studied revealing the presence of the hitherto unreported 18-hexacosenoic acid (18−26∶1). These results tend to
indicate that the biosynthetic pathway from 10−18∶1 to 18−26∶1 may be operative in nature. The phospholipid mixture from the
sponges was also analyzed by31P-NMR and shown to mainly consist of phosphatidylethanolamine, phosphatidylserine, phosphatidylinositol, and phosphatidylglycerol.
Phosphatidylcholine was not found in the sponges analyzed in this work. 相似文献
9.
The tests currently used to evaluate toxicity and ecotoxicity of polychlorinated biphenyls are reviewed. Distinction is made among acute toxicity, subacute toxicity, mutagenicity, and carcinogenic effects. The significance of the values obtained is briefly discussed 相似文献
10.
NM Carballeira M Reyes A Sostre H Huang MF Verhagen MW Adams 《Canadian Metallurgical Quarterly》1997,179(8):2766-2768
The fatty acid compositions of the hyperthermophilic microorganisms Thermotoga maritima and Pyrococcus furiosus were studied and compared. A total of 37 different fatty acids were identified in T. maritima, including the novel 13,14-dimethyloctacosanedioic acid. In contrast, a total of 18 different fatty acids were characterized, as minor components, in P. furiosus, and these included saturated, monounsaturated, and dicarboxylic acids. This is the first report of fatty acids from an archaeon. 相似文献