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63.
Maria V. MAZZAMUTO Andrea GALIMBERTI Giacomo CREMONESI Benoît PISANU Jean‐Louis CHAPUIS Jan STUYCK Giovanni AMORI Haijun SU Gaetano ALOISE Damiano G. PREATONI Lucas A. WAUTERS Maurizio CASIRAGHI Adriano MARTINOLI 《Integrative zoology》2016,11(3):214-228
Integrative taxonomy, a multi‐disciplinary approach adding modern techniques to traditional morphology‐based methods (e.g. molecular and morphological criteria), can play an important role in bioinvasion research to identify introduced taxa, discover pathways of introduction and inform authorities to control and prevent future introductions. The present study is the first on introduced populations of Callosciurus, Asiatic tree squirrels, known as potentially invasive species in Europe (Italy, Belgium and France). We combined molecular (mitochondrial DNA markers: CoxI, D‐loop) and morphometric analysis on skulls, comparing them to the widest morphological and molecular datasets ever assembled for Callosciurus. Squirrels collected in Italy and Belgium share the same haplotypes and skull characteristics, but are conspicuously different from the French population in Antibes. Genetic data revealed close similarity between French squirrels and Pallas's squirrels, Callosciurus erythraeus, from Taiwan, China. Italian and Belgian squirrels formed an independent taxonomic lineage in genetic analyses, whose taxonomic rank needs further investigation. The morphological and morphometric characteristics of these 2 populations are, however, similar to known specimens assigned to Callosciurus erythraeus. These results may indicate a common origin for the populations found in Belgium and Italy. In contrast, French specimens suggest an independent introduction event of squirrels originating from Asia. 相似文献
64.
Ranalli A Contento S Lucera L Pavone G Di Giacomo G Aloisio L Di Gregorio C Mucci A Kourtikakis I 《Journal of agricultural and food chemistry》2004,52(15):4795-4801
Carrot root oil (SCO), obtained by supercritical fluid carbon dioxide (SC-CO2) extraction, was characterized and compared to a commercial carrot oil (MCO) and a virgin olive oil (VOO) (cv. Coratina). SCO showed much higher contents of carotenes, phenolics, waxes, phytosterols, and sesquiterpene and monoterpene volatiles. In SCO, the most prominent components present in the fully investigated analytical fractions (fatty acids, triglycerides, waxes, phytosterols, long-chain aliphatic alcohols, superior triterpene alcohols, and volatiles) were, respectively, linolenic acid, trilinolein, waxes C38, beta-sitosterol, campesterol and stigmasterol, 1-hexacosanol, 24-methylencycloartanol and cycloartenol, beta-caryophyllene, alpha-humulene, alpha-pinene, and sabinene. In VOO, the major constituents of the above analytical classes were, respectively, oleic acid, trilinolein, waxes C36, unsaturated volatile C6 aldehydes (trans-2-hexenal most markedly), and the same prominent sterols and superior alcohols found in SCO. In MCO, which also contained a proportion of unknown plant oil, several components showed magnitudes that were lower compared to SCO but higher with respect to VOO. The last had the aliphatic and triterpene alcohol concentration higher compared to that of both SCO and MCO. Several chemometric methods, applied to different analytical data sets, proved to be effective in grouping the three oil kinds. 相似文献
65.
Giovanni Mastrolonardo Ornella Francioso Michele Di Foggia Sergio Bonora Claudia Forte Giacomo Certini 《Journal of Soils and Sediments》2015,15(4):769-780
Purpose
Pyrogenic organic matter (PyOM) in the soil of a maritime pine forest in Central Italy, formed during a fire of high severity, was characterised by Fourier transform infrared (FT-IR) and 13C nuclear magnetic resonance (NMR). Furthermore, soil samples from burnt and unburnt sampling sites and natural charcoal collected from the ground were characterised after progressive heating under air and nitrogen atmosphere. The aim was to better understand the role fire plays on PyOM formation and oxidation.Materials and methods
The top 10 cm of mineral soil and the above-lying charcoal particles were collected soon after the fire. Sampling was also performed on an adjacent unburnt portion of the forest. The bulk soil organic matter (SOM), its extractable fraction and charcoal particles were investigated by FT-IR and 13C NMR spectroscopies. They also underwent thermogravimetric analysis under air or N2, stopping the thermal reactions at the end of the first exothermic reaction in the range 350–500 °C.Results and discussion
The NMR investigation clearly revealed a significant enrichment in aromatic and alkyl C in the burnt soil compared to the unburnt one. Several clues led to hypothesise that SOM was not exposed to extreme heating during the fire, notwithstanding the high fire severity estimated by a vegetation-based visual scale. In the thermal treatment mimicking fire, charcoal lost much of its mass and carbon content. However, at 500 °C, it still maintained a significant recalcitrant fraction. Nitrogen concentration in the bulk soil increased after heating, particularly under air condition. This phenomenon could be due to the formation of heterocyclic nitrogen compounds in the charred material.Conclusions
In the study area, PyOM is rich in aliphatic compounds presumably because of the understory sclerophyllous vegetation typically found in Mediterranean environments. A large fraction of the charcoal released to the soil during the fire is sensitive to oxidation by subsequent fires. On the other hand, charcoal preserves a significant fraction of C, the most recalcitrant one, with expected long residence time in soil. PyOM formed under high oxygen availability is richer in N than that formed in inert atmosphere, which might make PyOM more susceptible to biochemical degradation.66.
Giacomo Certini Fiorenzo C. Ugolini Ioana Taina Giovanni Bolla Giuseppe Corti Francesca Tescari 《CATENA》2007
At about 1000 m above sea level in the Vallombrosa Forest, northern Apennines, Central Italy, a dense pan that meets the diagnostic criteria for fragipans is discontinuously distributed. The unusual slope-parallel “digitate” distribution of the pan suggests that it could have formed on water-saturated soil material that moved as earthflows. Actually, several soils in the Vallombrosa Forest have buried or truncated horizons, indicating episodes of mass movement and deposition. However, the fragipan under study shows a homogeneous morphology throughout, hence not providing clues about the occurrence of episodes that have contributed to the emplacement of the parent material. Also, the physical, chemical, and mineralogical analyses of the fragipan do not reveal discontinuities that help to resolve distinct episodes of deposition. Nevertheless, discontinuities in features such as the degree of alteration of biotite grains and the amount of plasma, seen through the micromorphological investigation at 50–60 cm of the current depth, suggest the occurrence of at least two depositional events. Radiocarbon dating of large-size pieces of charcoal collected at three depths within the fragipan yielded three ages that may reflect different times of accumulation of the parent material during the last glacial period. Post-depositional micromorphological features, such as relatively undamaged clay coatings and a weak platy structure, indicate pedogenesis with the absence of intense pedoturbation. 相似文献
67.
Dugo G La Pera L Lo Turco V Di Bella G Salvo F 《Journal of agricultural and food chemistry》2004,52(7):1829-1834
The purpose of this paper was to use adsorptive stripping chronopotentiometry for the determination of Ni (II) in worldwide consumed beverages without any sample pretreatment, using dimethilglyoxime (DMG) as complexing agent and a glassy carbon mercury film electrode as the working electrode. Ni (DMG)2 complex is adsorbed onto the mercury film at an electrolysis potential of -500 mV for 60 s and then reduced by a -5 microA constant cathodic current. The sensitivity of the method was studied for certified reference water and black tea in the pH range 6.5-11. At pH 9.5 in ammonia buffer, a detection limit of 0.2 microg L(-1) was achieved; the instrumental precision (expressed as rsd %) was 1.5%, and the accuracy, expressed as obtained recoveries both from certified and not certified matrixes, ranged from 93.0 to 95.5 %. The chronopotentiometric analysis executed on commercial beverages provided evidence that black tea samples were the richest source of Ni (II) (1500-3700 microg L(-1)), followed by coffee (100.0-300.5 microg L(-1)); bottled mineral water showed a Ni (II) concentration lower than 4.6 microg L(-1). Among alcoholic beverages, red wines presented the highest content of Ni (II) (55.5-105.0 microg L(-1)). Significant differences were noticed between Ni (II) levels of fermented and distillated alcoholic beverages; moreover, canned cola and beer did not show higher Ni (II) levels with respect to the glass-bottled products. 相似文献
68.
Giacomo Pietramellara Judith Ascher Maria Teresa Ceccherini Paolo Nannipieri Dirk Wenderoth 《Biology and Fertility of Soils》2007,43(6):731-739
Several studies have investigated the adsorption of pure DNA on soil particles and its transformation ability. However, the presence of not purified (dirty) rather than pure DNA is more common in the extracellular soil environment. For this reason, we have investigated the adsorption
and binding of dirty DNA on montmorillonite (M) and kaolinite (K) and their transforming ability in comparison to pure DNA.
After lysis of Bacillus subtilis cells, induced by KCl, dirty DNA was characterized by the presence of cellular wall debris (cwd) and other constitutional organic components (coc). The dirty DNA was then divided into two fractions, one with cellular wall debris (DNA +cwd) and the other without cellular
wall debris (DNA −cwd). B. subtilis BD 1512 (Cmr) and BD 170 (Cms) were selected as donor and recipient bacteria, respectively, for adsorption and transformation studies. Both cwd and coc
seem to facilitate the adsorption of DNA to clay minerals, whereas only cwd promote the DNA binding on clays, protecting also
the DNA fragments below 400 bp against nucleases. Both dirty DNA fractions adsorbed and bound on clay minerals were able to
transform competent cells. 相似文献
69.
Riccardo Riffaldi Renato Levi-Minzi Alessandro Saviozzi Giacomo Vanni Alessandra Scagnozzi 《Water, air, and soil pollution》1993,69(3-4):257-264
A laboratory experiment was performed during a 40-day incubation period in order to evaluate changes in organic and inorganic compounds of soil amended with two doses of sludge obtained from olive-oil processing waste waters. Differences between the amounts of organic components of the amended soil and those of the control, although related to doses and sampling time, disappeared at the end of the experimental period. On the contrary, the inorganic anion contents were still different for the various treatments, which suggest, especially for NO3 ? and SO4 2?, a transient inhibition in the soil-sludge system. A germination test, carried out on the soil amended with different doses of sludge, indicates that after about twenty days even the soil containing the highest dose of sludge did not show toxicity any longer. 相似文献
70.
Alberto Agnelli Judith Ascher Maria Teresa Ceccherini Giacomo Pietramellara 《Soil biology & biochemistry》2004,36(5):859-868
We studied the distribution of the indigenous bacterial and fungal communities in a forest soil profile. The composition of bacterial and fungal communities was assessed by denaturing gradient gel electrophoresis (DGGE) of total and extracellular DNA extracted from all the soil horizons. Microbial biomass C and basal respiration were also measured to assess changes in both microbial biomass and activity throughout the soil profile. The 16S rDNA-DGGE revealed composite banding patterns reflecting the high bacterial diversity as expected for a forest soil, whereas 18S rDNA-DGGE analysis showed a certain stability and a lower diversity in the fungal communities. The banding patterns of the different horizons reflected changes in the microbial community structure with increasing depth. In particular, the DGGE analysis evidenced complex banding patterns for the upper A1 and A2 horizons, and a less diverse microflora in the deeper horizons. The low diversity and the presence of specific microbial communities in the B horizons, and in particular in the deeper ones, can be attributed to the selective environment represented by this portion of the soil profile. The eubacterial profiles obtained from the extracellular DNA revealed the presence of some bands not present in the total DNA patterns. This could be interpreted as the remainders of bacteria not any more present in the soil because of changes of edaphic conditions and consequent shifting in the microbial composition. These characteristic bands, present in all the horizons with the exception of the A1, should support the concept that the extracellular DNA is able to persist within the soil. Furthermore, the comparison between the total and extracellular 16S rDNA-DGGE profiles suggested a downwards movement of the extracellular DNA. 相似文献