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11.
A fish kill was recorded at the Aposelemis Dam, which is the main reservoir of drinking water for the island of Crete in Greece. Hundreds of goldfish were found dead at a side stream which provides water to the reservoir. The affected fish had been entrapped in a small pond at the side of the stream with practically zero water renewal as the event occurred in August which is a dry season for the island of Crete. The event was alarming for the local community since anthropogenic pollution was initially suspected which could pose a significant human health threat. Following examination of the fish, the mortality was attributed to heavy infection by the parasitic flagellate, Ichthyobodo sp., whilst no pollutants were detected. The parasite was studied through light and scanning electron microscopy and was identified molecularly.  相似文献   
12.
Twenty-five compounds were identified from the dichloromethane and methanol extracts of royal jelly from Greece. Among them, 16 compounds are reported for the first time as royal jelly constituents, whereas 7 of them are isolated for the first time as natural products. The 7 new compounds were fatty acid derivatives: 10-acetoxydecanoic acid (1), trans-10-acetoxydec-2-enoic acid (2), 11-oxododecanoic acid (3), (11S)-hydroxydodecanoic acid (4), (10R,11R)-dihydroxydodecanoic acid (5), 3,11-dihydroxydodecanoic acid (6), and (11S),12-dihydroxydodecanoic acid (7). The structures of the isolated compounds were determined by spectroscopic methods, mainly by the concerted application of 1D and 2D NMR techniques (HMQC, HMBC) and mass spectrometry. The studied sample and the isolated compounds were tested for their antimicrobial activity against Gram-positive and Gram-negative bacteria and fungi and exhibited interesting activities.  相似文献   
13.
Bio-economic models can be used to assess the impact of policy and environmental measures through economic and environmental indicators. Focusing on agricultural systems, farmers’ decisions in terms of cropping systems and the associated crop management at field scale are essential in such studies. The objective of this paper is to present a study using a bio-economic model to assess the impact of the Nitrate Directive in the Midi-Pyrenees region (France) by analyzing, at the farm scale, farm income and three environmental indicators: nitrate leaching, erosion and water consumption. Two scenarios, the 2003 CAP reform (baseline scenario) and the Nitrate Directive (policy scenario), with a 2013 time horizon, were developed and compared for three representative arable farm types in the Midi-Pyrenees region. Different types of data characterizing the biophysical context in the region (soil, climate), the current cropping systems (rotation, crop management) and farm resources (irrigated land, labor) were collected to calibrate and run the models. Results showed that the implementation of the Nitrate Directive may not affect farm income. However, significant modifications to cropping systems and crop allocation to soil types were simulated. Contrary to expectations, nitrogen leaching at the farm scale did not change. Overall water consumption increased and soil erosion decreased due mainly to a modification in cropping patterns and management by soil type. This study provides an example of unanticipated effects of policy and trade-offs between environmental issues.  相似文献   
14.
15.
This study was conducted to evaluate the effect of sowing rates and organic fertilization on growth and yield biomass quality of chia crop. The agronomic performance and nutritive value of chia were analyzed in order to define alternatives to local forages for dry-season feeding of ruminants in the Mediterranean region. Two sowing rates were arranged in the main plots and three levels of organic fertilization in the subplot with three replicates in split-plot design. Chia growth was not affected by sowing rates and fertilization. Concerning the dry weight and leaf area index (LAI), there were no significant differences among fertilization treatments while sowing rates influenced both dry and LAI, which were significantly increased as sowing rates increased. Forage quality traits were not significantly influenced by sowing rates. With regard to crude protein content, fertilization treatments had a positive effect. The greatest values were observed under manure treatment. Moreover, significant increases were revealed in the crude protein yield as sowing rates increased. In addition, acid detergent fiber (ADF) as well as neutral detergent fiber (NDF) were not affected by sowing rates but there were significant differences between fertilization treatments. Data suggest that chia could be successfully used as an alternative forage crop.  相似文献   
16.
The adsorption of copper (Cu(II)) from aqueous solutions by activated Luffa cylindrica biochar fibres has been investigated by means of batch equilibrium experiments and FTIR spectroscopy. The effect of various physicochemical parameters, such as pH, initial metal concentration, ionic strength, mass of the adsorbent, contact time and temperature, has been evaluated by means of batch type adsorption experiments. FTIR spectroscopy, as well as acid-base titrations, was used for the characterization of the material and the surface species formed. According to the experimental results even at pH 3, the relative sorption is above 85% and the adsorption capacity of the activated biochar fibres for Cu(II) is q max = 248 g kg?1. Moreover, the interaction between the surface carboxylic moieties and Cu(II) results in the formation of very stable inner-sphere complexes (?G o = ?11.2 kJ mol?1 at pH 3 and ?22.4 kJ mol?1 at pH 5.5).  相似文献   
17.
In the Mediterranean region, cold-stored plants (summer planting system) are used as the main strawberry planting material (plant establishing period July–August). However, recently fresh plants (winter planting system) have also started being used for strawberry production (plant establishing period October–November). As the plantations originated from cold-stored or fresh plants differ in plant growth and yield, some differences in fruit quality have also been expected; therefore, the objective of the current study was to compare fruit quality of plants originated from different propagation material. Cold-stored plants were well developed before the beginning of the spring harvest, while fresh plants continued growth concomitantly with fruiting. The harvesting period of cold-stored plants lasted 4–6 weeks (second week of April–second half of May). Fresh plants produced fewer and larger fruits than cold-stored plants, but for a longer harvest period, which lasted throughout all summer. Differences in soluble solids and dry matter content between the fruits from cold-stored and fresh plants were observed in the first three sampling dates in both years of the experiment. In some sampling dates, significant differences in anthocyanin, titratable acidity and ascorbic acid content, were observed between fruits of plants originated from different propagation material.  相似文献   
18.
A previous publication (Kokkinofta et al. J. Agric. Food Chem. 2003, 51, 6233-6239) discussed the use of inductively coupled plasma spectroscopy to differentiate between the traditional Cypriot alcoholic beverage zivania and other spirits similar in alcoholic content collected from different countries. In the present paper (1)H NMR spectroscopy is applied to confirm the previous conclusions and to obtain additional physical-chemical characteristics that may be used to differentiate zivania from other similar beverages. NMR spectroscopy gave a satisfactory degree of prediction and classification between zivanias and other distillings. The validity of quantification of the method was tested using comparative GC data. It appears that chemical analysis can be very helpful for identifying the unique geological and climatic conditions existing in the island of Cyprus that lead to an authentic product.  相似文献   
19.
Inflammatory bowel disease is characterized by extensive intestinal inflammation, and therapies against the disease target suppression of the inflammatory cascade. Nutrition has been closely linked to the development and suppression of inflammatory bowel disease, which to a large extent is attributed to the complex immunomodulatory properties of nutrients. Diets containing fish have been suggested to promote health and suppress inflammatory diseases. Even though most of the health-promoting properties of fish-derived nutrients are attributed to fish oil, the potential health-promoting properties of fish protein have not been investigated. Fish sidestreams contain large amounts of proteins, currently unexploited, with potential anti-inflammatory properties, and may possess additional benefits through bioactive peptides and free amino acids. In this project, we utilized fish protein hydrolysates, based on mackerel and salmon heads and backbones, as well as flounder skin collagen. Mice fed with a diet supplemented with different fish sidestream-derived protein hydrolysates (5% w/w) were exposed to the model of DSS-induced colitis. The results show that dietary supplements containing protein hydrolysates from salmon heads suppressed chemically-induced colitis development as determined by colon length and pro-inflammatory cytokine production. To evaluate colitis severity, we measured the expression of different pro-inflammatory cytokines and chemokines and found that the same supplement suppressed the pro-inflammatory cytokines IL-6 and TNFα and the chemokines Cxcl1 and Ccl3. We also assessed the levels of the anti-inflammatory cytokines IL-10 and Tgfb and found that selected protein hydrolysates induced their expression. Our findings demonstrate that protein hydrolysates derived from fish sidestreams possess anti-inflammatory properties in the model of DSS-induced colitis, providing a novel underexplored source of health-promoting dietary supplements.  相似文献   
20.
Two composts were prepared from olive press cake (OPC) repeatedly turned and moistened with either olive mill wastewater (OPC+OMW) or water (OPC+W). When phytotoxicity was drastically reduced and the pH of the composts had reached 8.6 and 7.55 respectively, elemental sulfur was added at 0.9% of dry weight to the OPC+OMW compost and at five different doses (0.1 – 1.0% of dry wt) to the OPC+W compost. During the following six months, an exponential pH decline was observed in both compost materials. The pH reached a final value of 5.8 in the OPC+OMW compost whereas a pH decline related to the amount of added sulfur was observed in the OPC+W compost (final values from 6.8 to 4.3). Over 80% of the pH decline occurred during the first two months following the sulfur addition. Sulfur was applied following the stabilization of the material in the case of OPC+W. No phytotoxic effects of the final products were observed at sulfur application doses up to 0.5% of dry compost weight, but a significant germination index reduction was observed at the 1% dose, probably related to the increased conductivity of the compost leachate. Sulfur was applied before stabilization of the compost material, in the case of OPC+OMW, to also investigate the effects of sulfur addition on the composting process. A thermophilic phase similar to that observed after the last OMW application exceeding 50°C followed, and no effects on microbial activity profiles of the compost were observed. The results indicate that small amounts of elemental sulfur may efficiently control high pH values in the final compost products and could be safely applied at late composting stages or after composting. This may broaden the utilization of these composts in potting media and alkaline soils.  相似文献   
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