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101.
This study aimed to compare the fertility of eggs between artificially matured female silver eels that spawned spontaneously and those that were spawned by manual stripping. The effects of the two methods of spawning on ovulation and fertilization rate were also investigated. For this purpose, 18 wild female European eels captured in Bonello lagoon (North Adriatic Sea) were carp pituitary extract‐injected to undergo sexual maturation and ovulation; a final injection of 17,20β‐dihydroxy‐4‐pregnen‐3‐one (DHP) was administered when at least 30% of the oocytes were fully transparent. After the DHP‐injection, nine eels were transferred to a new closed recirculating aquaculture system, where they were housed with spermiating males (sex ratio 4/1) to allow spontaneous spawning (SPT‐group); the remaining nine eels were transferred to a 250 L tank and ovulation was checked at four‐hourly intervals by manual stripping (STR‐group). The number of eggs per female in the SPT‐group was significantly greater than that in the STR‐group. Furthermore, fertilization rates in the SPT‐group were notably higher than those observed in the STR‐group. Significantly, the best performances were obtained among eels in which at least 50% of oocytes were fully transparent at the time DHP was administered. We conclude that the fertility of eggs from spontaneously spawning eels is superior to that of eggs acquired by strip‐spawning and artificial fertilization.  相似文献   
102.
103.
Fusarium corm rot of saffron (Crocus sativus L.), incited by Fusarium oxysporum f. sp. gladioli, causes severe yield losses in Italy. Major symptoms during flowering (October–November) include yellowing and wilting of shoots, basal stem rot and corm rot. Sixty-four isolates of F. oxysporum f. sp. gladioli, obtained from infected saffron crops located in Italy (Abruzzi, Tuscany and Umbria) and in Spain, were characterized by pathogenicity and vegetative compatibility. Chlorate-resistant, nitrate-nonutilizing (nit) mutants were used to determine vegetative compatibility among the isolates of the pathogen with the aim of examining the genetic relatedness among populations from different locations. All the isolates belonged to vegetative compatibility group 0340. Since saffron shares susceptibility to F. oxysporum f. sp. gladioli with other ornamental plants of the Iridaceae (Crocus, Gladiolus, Iris and Ixia), it is likely that a clone of the pathogen (VCG 0340) was introduced with other hosts and is responsible for the disease outbreak observed on saffron in Italy. Alternatively, or additionally, the clone of F. oxysporum f. sp. gladioli causing disease on saffron in other countries may have spread to the saffron fields in Italy through the import and dispersal of infested propagation material.  相似文献   
104.
105.
The total phenolic, flavanol, monomeric anthocyanin contents and the antioxidant activity of flesh and peel of 11 apple cultivars from Brazil were investigated. Concentrations of the parameters measured differed significantly among the apple cultivars and were highest in the peel compared to the flesh. Total phenolic content (mg GAE/100 g fresh matter) ranged from 128.3 (Golden Delicious) to 212.0 (Epagri-F5P283) in the flesh and 304.6 (Golden Delicious) to 712.6 (Catarina) in the peel. Total flavanol content (mg CAE/100 g fm) varied from 11.7 (Epagri-SJ11) to 28.2 (Epagri-F43P23) and from 32.4 (Epagri-SJ11) to 147.7 (Catarina) in the flesh and peel, respectively. COOP-24 peel had the highest total anthocyanin content. The Epagri-F5P283 and Epagri-F43P23 flesh and Catarina peel had the highest antioxidant activity while Golden Delicious flesh and peel had the lowest. The total phenolic content and antioxidant activity were significantly correlated in both flesh (R2 = 0.717) and peel (R2 = 0.716). The contribution of phenolics to the antioxidant activity in peel suggests that their removal may induce a significant loss of antioxidants.  相似文献   
106.
A total of 12 fatty acid esters of Z- and E-p-coumaryl alcohol were isolated from cv. Annurca apple fruit and characterized. This apple variety is widely cultivated in the south of Italy, and the fruits typically undergoe a reddening treatment after harvest. Structures of the p-coumaryl esters were elucidated by GC-MS and (1)H and (13)C NMR after purification of individual compounds by HPLC. It was found that the esters are localized in the fruit peel. During reddening of the fruit, there was a substantial increase in the amount of esters and particularly in molecular species with unsaturated fatty acids. The individual compounds were tested for antioxidant activity, and over half were shown to be at least as effective as alpha-tocopherol.  相似文献   
107.
Summary Exploration and collection of plant genetic resources were continued in central Italy 1989—regions Abruzzo, Umbria, Marche, Toscana.Triticum dicoccon was used as an indicator for traditional agriculture. 169 accessions were collected, mainly of cereals, vegetables and grain legumes. Worth mentioning are land-races ofTriticum aestivum, T. durum, Secale cereale, Pisum sativum, Lactuca sativa andCucurbita maxima. Brassica oleracea var.palmifolia, the palm-leaved kale, is an important vegetable in the Toscana. Several other rare crops could be also collected.
Sammlung pflanzlicher genetischer Ressourcen in Italien 1989
Zusammenfassung Die Exploration und Sammlung pflanzlicher genetischer Ressourcen wurden 1989 in Mittelitalien fortgesetzt — Regionen Abruzzo, Umbria, Marche, Toscana.Triticum dicoccon wurde als Indikator für traditionelle Landwirtschaft verwendet. 169 Proben wurden gesammelt, hauptsächlich von Getreiden, Gemüsen und Körnerleguminosen. Erwähnenswert sind Landsorten vonTriticum aestivum, T. durum, Secale cereale, Pisum sativum undCucurbita maxima. Brassica oleracea var.palmifolia, der Palmkohl, ist ein wichtiges Gemüse in der Toscana. Verschiedene andere seltene Fruchtarten konnten ebenfalls gesammelt werden.

1989
1989 , , , .Triticum dicoccon . 169 , , . Triticum aestivum, T. durum, Secale cereale, Pisum sativum Cucurbita maxima. Brassica oleracea var.palmifolia, , . .
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108.

Purpose

Microwave heating (MWH) has been recently proposed as a high-performance technique for the remediation of soils contaminated with organic pollutants. However, despite MWH potential advantages, it is scarcely applied due to the lack of full-scale in situ detailed studies. In this work, the in situ MWH applicability for the remediation of hydrocarbon-polluted soils was assessed by means of a specific energy and economic analysis. Essential technical information has also been purchased.

Materials and methods

Energy and economic analysis was performed using data obtained from modelling for which a dedicated equation-based process computer code simulating MWH phenomena was adopted. Elaborations involved the assessment of the influence of soil texture and moisture as well as operating conditions (supplied power and time) on electric field penetration into the soils and soil temperature variation as a function of time and radial distance from the irradiation source.

Results and discussion

Main results reveal that sandy soils are more penetrable by MW irradiation with respect to clayey ones. The soil MW penetrability was also observed to increase with decreasing the soil moisture. This was in turn reflected in the soil temperature profiles. However, the major effect on MWH effectiveness is ascribable by the changing of the operating power. In fact, the use of magnetrons with powers lower than 3 kW does not ensure enough microwave penetration into the soil and, therefore, is not suitable for in situ activities, whereas the application of a power of 6 kW led to a maximum treatable radius of 145 cm. In terms of energy consumption, calculation showed that almost 3 days more are in general required to remediate clayey soils with respect to sandy ones. Consequently, the economic analysis revealed that energy costs for sandy soils are about 3 € t?1 lower than those required for clayey soils. Furthermore, the application of a power of 6 instead of 3 kW results in a higher total energy cost, which, jointly with the higher soil volume treatable, leads to almost equal specific costs.

Conclusions

The comparison of calculated costs with those of other available clean-up technologies for hydrocarbon-contaminated soils shows that very short remediation times and energy costs obtained (18–27 € t?1) make in situ MWH a deliverable alternative to conventional thermal desorption or physical-chemical techniques.
  相似文献   
109.
BACKGROUND: The correlation between pesticide residue levels and formulation of an active substance is often not considered, even if it is reasonable to expect some differences arising from behaviour during dilution and spraying, from adhesion to plant and from degradation. An experimental study to investigate the magnitude of tebuconazole residues as a function of different tebuconazole formulated products was carried out in Italy. The fungicide was applied as wettable powder (WP) and water‐dispersible granule (WG) formulations to peach, plum, apricot and nectarine orchards, on four different sites. The fruit samples gained from the field trials were quantitatively analysed by gas chromatography with a nitrogen phosphorus detector (GC/NPD) for tebuconazole residues. RESULTS: Tebuconazole residues in the fruits gained from the plot treated with the WP formulation, 14 days after application, were in the range 0.01–0.07 mg kg?1, while corresponding residues in the plot treated with the WG formulation were in the range 0.01–0.06 mg kg?1. CONCLUSION: No significant differences in the residue levels of tebuconazole could be observed between the trials conducted with the WP and the WG formulation. Copyright © 2009 Society of Chemical Industry  相似文献   
110.
This paper reports the synthesis and the biological activity of benzoyl arylureas in which the aryl group bears a trifluoromethyl-substitiited alkyl or alkenyl side chain, R. The activity of these compounds has been evaluated on larvae of S. littoralis, A. aegypti, L. decemlineata and on the eggs of T. urticae. In general: (1) the optimum insecticidal activities are achieved when the substituents on the benzoyl moiety, R1, and R2, are 2,6-difluoro, the substituents on the aryl moiety, R3, are 3,5-dichloro and R1, is 4-(? CH?C(CI)CF3); (2) the best acaricidal activity is shown when R1, is 2-CI, R2, and R3, are hydrogen atoms and R1, is 4-(? CH2CH2CH(CI)CF3); (3) the best overall activity is displayed when R1, is 2-CI, R2 is hydrogen, R3 is 3-chloro and R1 is 4-(? CH2CH2CF3).  相似文献   
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