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991.
Medeiros Vinci R Mestdagh F Van Poucke C Kerkaert B de Muer N Denon Q Van Peteghem C De Meulenaer B 《Journal of agricultural and food chemistry》2011,59(3):898-906
This study evaluated various additives or process aids on the industrial production of French fries, based on their acrylamide mitigation potential and other quality parameters. The application of acetic and citric acid, calcium lactate and asparaginase was investigated on the production of frozen par-fried French fries at the beginning and end of the 2008 and 2009 potato storage season. Despite the fact that some of these treatments significantly reduced acrylamide content of the final product in preliminary laboratory experiments, their application on the industrial production of French fries did not result in additional acrylamide reductions compared to the standard product. Asparaginase was additionally tested in a production line of chilled French fries (not par-fried). Since for this product a longer enzyme-substrate contact time is allowed, a total asparagine depletion was observed for the enzyme treated fries after four days of cold storage. French fries upon final frying presented acrylamide contents below the limit of detection (12.5 μg kg?1) with no effects on the sensorial properties of the final product. 相似文献
992.
Skin burning is a new type of skin damage related to exposure to high pH values during the brushing-waxing postharvest operations that has been observed recently on some newly released peach and nectarine [Prunus persica (L.) Batsch] cultivars. In this work, we described this skin disorder for the first time and studied its triggers and biological basis. Different skin burning susceptibility was observed after screening 21 peach and nectarine cultivars. The stability of the skin phenolic extracts to pH in the range 7-10 was studied by UV-visible spectroscopy. This study demonstrated that fruit skin phenolics are not stable at high pH and that the transformations occurring at high pH are reversible and time-dependent. The changes on the UV-visible absorption spectra at different pH values pointed out the copigmentation of anthocyanins as the mechanism beyond the skin burning disorder. Finally, some recommendations to minimize this postharvest damage are also discussed. 相似文献
993.
Tathiane Santi Sarcinelli Carlos Ernesto G.R. Schaefer Leila de Souza Lynch Helga Dias Arato João Herbert M. Viana Manoel Ricardo de Albuquerque Filho Teresa Telles Gonçalves 《CATENA》2009
Little is known about the effects of neotropical mound-building termites in soil chemical and physical properties. The influence of soil termite activity on soil characteristics was studied by assessing chemical, physical and micromorphological properties of a toposequence of Latosols (Oxisols). Soil samples were collected from the walls and inner parts of termite mounds and also from adjacent soil. A high diversity of termite genera was found in the mounds along the toposequence, together with the inquiline termites and other soil-dwelling arthropods. Chemical analyses showed that pH and the contents of organic C and N, P, Ca and Mg were significantly higher in termite mounds compared with adjacent areas, with an inverse trend for Al content. Significant differences in pH and exchangeable Al were observed between soil and mound across the slopes. The mound density across the landscape was higher at the upper slope segment, followed by the hill top, middle slope and lower slope segments. Considering a lifespan of 30 years and dimensions of termite mounds found in the toposequence we conclude that the textural and chemical uniformity of Latosols may be increased, following the pedobiological turnover during mound building, with local rates varying from 2.1 to 7.5 m3 ha− 1. 相似文献
994.
Ecosystem service supply and vulnerability to global change in Europe 总被引:12,自引:0,他引:12
Schröter D Cramer W Leemans R Prentice IC Araújo MB Arnell NW Bondeau A Bugmann H Carter TR Gracia CA de la Vega-Leinert AC Erhard M Ewert F Glendining M House JI Kankaanpää S Klein RJ Lavorel S Lindner M Metzger MJ Meyer J Mitchell TD Reginster I Rounsevell M Sabaté S Sitch S Smith B Smith J Smith P Sykes MT Thonicke K Thuiller W Tuck G Zaehle S Zierl B 《Science (New York, N.Y.)》2005,310(5752):1333-1337
Global change will alter the supply of ecosystem services that are vital for human well-being. To investigate ecosystem service supply during the 21st century, we used a range of ecosystem models and scenarios of climate and land-use change to conduct a Europe-wide assessment. Large changes in climate and land use typically resulted in large changes in ecosystem service supply. Some of these trends may be positive (for example, increases in forest area and productivity) or offer opportunities (for example, "surplus land" for agricultural extensification and bioenergy production). However, many changes increase vulnerability as a result of a decreasing supply of ecosystem services (for example, declining soil fertility, declining water availability, increasing risk of forest fires), especially in the Mediterranean and mountain regions. 相似文献
995.
996.
Carlos Alexandre Costa Crusciol Otavio Bagiotto Rossato Rodrigo Foltran Jorge Martinelli Martello 《Communications in Soil Science and Plant Analysis》2017,48(19):2314-2323
The aim of this study was to verify if the application of silicate or lime, in association with gypsum, on sugarcane residue can lead to amendment of subsurface soil acidity, increasing sugarcane yield and profitability. The treatments were: 1 – control (without application of amendments), 2 – gypsum, 3 – dolomitic limestone, 4 – silicate, 5 – dolomitic limestone + gypsum, and 6 – silicate + gypsum. The surface application of gypsum led to reduction in Al (aluminum) contents and Al saturation, and increase in Mg+2, Ca+2, K+, S–SO4?, and base saturation in deeper soil layers, as well as increased yield of stalks, sugar, trash, bagasse, and energy, and greater profit. The application of limestone and silicate, alone or in association with gypsum, amend soil acidity throughout the soil profile. It likewise leads to an increase in stalk, sugar, trash, bagasse, and energy yield, however, application of silicate in association with gypsum leads to the greatest profitability. 相似文献
997.
998.
Ricardo Borjas-Ventura Antonio Sergio Ferraudo Carlos Alberto Martínez Priscila Lupino Gratão 《Journal of Agronomy and Crop Science》2020,206(1):13-27
Drought can be more frequent and severe along with elevated temperatures (eT). To deal with the climate change impact on plants, we need to understand the plant biochemical performance. Nowadays, there is a lack of information about the antioxidant response of plants, mainly growing in field conditions and under the future climatic scenario. In this context, we carried out this experiment to analyse the antioxidant responses of the forage legume Stylosanthes capitata Vogel (in field condition) to eT and water deprivation. This work had four treatments: control, eT (+2°C above ambient canopy temperature), wS (water deprivation) and eT + wS. Temperature free-air controlled enhancement (T-FACE) system was used for warming, and samples were taken 17, 24 and 46 days after warming exposure at time periods of 6:00 a.m. and 12:00 p.m. The eT + wS treatments decreased catalase, superoxide dismutase (SOD) and ascorbate peroxidase activities, especially at 46 days. Nevertheless, glutathione (GSH) content was not modified by eT + wS treatments. Also, we determined an important inverse relation among SOD-GR-GSH and MDA-H2O2. In conclusion, combined stresses provoked detrimental effects of enzymatic antioxidant responses. Furthermore, we highlighted the importance of SOD-GR and GSH to avoid damages of reactive oxygen species in S. capitata grown under climate change. In addition, we suggest an adequate irrigation management in order to improve the antioxidant systems to face the eT, successfully; besides, we consider that the uses of tolerant cultivars are key under climate change conditions. 相似文献
999.
1000.
Carlos E.C. Freitas Flávia K. Siqueira‐Souza Alexandro C. Florentino Lawrence E. Hurd 《Ecology of Freshwater Fish》2014,23(3):470-477
The Amazon River Basin has the highest fish species diversity of any region in the world, but is under threat from anthropogenic perturbations including overharvesting, alien species and drought. We asked whether species diversity in this region is more a function of within‐lake species richness (i.e., α diversity) or differences among lakes (β diversity). Although many studies have reported on species richness and diversity in single habitats, the importance of measuring diversity at different spatial scales is not yet well established. We collected fish in 10 floodplain lakes along the Solimões River (Brazil), divided evenly between two lake types: those on islands in the river channel (island lakes) and those on the margins of the river (coastal lakes) during 2006. We partitioned fish diversity into three spatial scales: α = within each lake; β1 = among lakes of the same type (coastal or island) and β2 = between the two types of lakes, and compared their relative contributions to regional (γ) diversity. β1 + β2 contributed as much or more to γ diversity than did α. Although many of the 116 fish species were shared between lake types (S = 72), 32 species were found exclusively in coastal lakes and 12 species were found exclusively in island lakes. Coastal lakes, which were deeper and cooler than island lakes, consistently had higher fish species richness than island lakes. We suggest that it will be necessary to set areas large enough to contain multiple lakes of both types to preserve regional fish diversity. 相似文献