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101.
Luigi Todaro Roberto Zanuttini Antonio Scopa Nicola Moretti 《Wood Science and Technology》2012,46(1-3):563-578
A combined effect of steaming and heat treatment was imposed on green Turkey oak wood, both for sapwood and heartwood. Steaming was carried out in an autoclave at 100–120–130°C whereas heating was carried out in an oven for 2?h at 120–180°C. Equilibrium moisture content at dry, intermediate and moist state both in desorption and adsorption, swelling, cup, twist, color change, and spectral reflectance measures were registered. Swelling and water absorption decreased due to the hydro-thermal treatment. During adsorption, heartwood showed a higher hygroscopic inertia compared to sapwood and this difference increased with temperature. Cup increased with temperature in the steaming process. Twist seemed to be affected more by quality of original trunks than treatments. The wood color was more sensitive at a steaming temperature of 130°C combined with heat treatment at 180°C. Transitional treatments assured more reliable results on homogenization of hue between sapwood and heartwood. 相似文献
102.
连续五年生物垃圾堆肥施用后地中海蔬菜种植系统中土壤有机碳的变化 总被引:1,自引:0,他引:1
Biowaste compost can influence soil organic matter accumulation directly or indirectly. A 5-year experiment was conducted to assess the influence of biowaste compost on the process of soil aggregation and soil organic carbon(SOC) accumulation in a Mediterranean vegetable cropping system. The study involved four treatments: biowaste compost(COM), mineral NPK fertilizers(MIN), biowaste compost with half-dose N fertilizer(COMN), and unfertilized control(CK). The SOC stocks were increased in COM, COMN, and MIN by 20.2, 14.9, and 2.4 Mg ha~(-1)over CK, respectively. The SOC concentration was significantly related to mean weight diameter of aggregates(MWD)(P 0.05, R~2= 0.798 4) when CK was excluded from regression analysis. Compared to CK, COM and COMN increased the SOC amount in macroaggregates( 250 μm) by 2.7 and 0.6 g kg~(-1)soil, respectively, while MIN showed a loss of 0.4g kg~(-1)soil. The SOC amount in free microaggregates(53–250 μm) increased by 0.9, 1.6, and 1.0 g kg~(-1)soil for COM, COMN, and MIN, respectively, while those in the free silt plus clay aggregates( 53 μm) did not vary significantly. However, when separating SOC in particle-size fractions, we found that more stable organic carbon associated with mineral fraction 53 μm(MOM-C) increased significantly by 3.4, 2.2, and 0.7 g kg~(-1)soil for COM, COMN, and MIN, respectively, over CK, while SOC amount in fine particulate organic matter(POM) fraction(53–250 μm) increased only by 0.3 g kg~(-1)soil for both COM and COMN, with no difference in coarse POM 250 μm. Therefore, we consider that biowaste compost could be effective in improving soil structure and long-term C sequestration as more stable MOM-C. 相似文献
103.
Baggenstoss J Poisson L Kaegi R Perren R Escher F 《Journal of agricultural and food chemistry》2008,56(14):5847-5851
Initial moisture of green coffee may vary as a function of green coffee processing and storage conditions. The impact of initial moisture and steam treatment on roasting behavior and aroma formation was investigated. Steam treated coffees as well as coffees with initial moisture content of 5.10, 10.04, and 14.70 g water per 100 g wb were roasted. Light and dark roasting trials were carried out using a fluidizing-bed roaster with a batch size of 100 g of green beans. Differences in roast coffee attributes, that is, color, density, and organic roast loss, and odorant concentrations were more marked in light roasted than in dark roasted coffees. The results of roasting steam treated coffee suggest that this step affects roasting behavior primarily by extracting some aroma precursor compounds. 相似文献
104.
Fazzari M Fukumoto L Mazza G Livrea MA Tesoriere L Marco LD 《Journal of agricultural and food chemistry》2008,56(10):3561-3568
The bioavailability of phenolic compounds from five cultivars of frozen sweet cherries was assessed by a digestion process involving pepsin-HCl digestion (to simulate gastric digestion) and pancreatin digestion with bile salts (to simulate small intestine conditions) and dialyzed to assess serum- and colon-available fractions. After pepsin digestion, the % recovery of total phenolics, relative to the original starting material, increased, whereas the % anthocyanins did not change. Following pancreatic digestion and dialysis, the total phenolics in the IN (serum-available) fraction was about 26-30% and the OUT (colon-available) fraction was about 77-101%. The anthocyanin content in the IN fraction was 15-21%, and in the OUT fraction, it was 52-67%. Skeena, Lapins, and Sweetheart cultivars contained higher levels of total phenolics and anthocyanins, which resulted in higher concentrations of these compounds in the IN and OUT fractions. The potential bioavailability of phenolic compounds was also assessed in Bing and Lapins cultivars at three ripening stages. Immature cherries had higher % total phenolics in the IN fraction than mature or overmature cherries. However, immature cherries had the lowest concentrations of these compounds, making the actual bioavailable amounts of these compounds lower than for mature and overmature fruit. High-performance liquid chromatography analysis of Lapins cherries at three maturity stages confirmed the results obtained using spectrophotometric methods for total phenolics and anthocyanins. 相似文献
105.
Bavaresco L Vezzulli S Civardi S Gatti M Battilani P Pietri A Ferrari F 《Journal of agricultural and food chemistry》2008,56(6):2085-2089
Berries of Vitis vinifera L. cv. Merlot, grown on a neutral or calcareous soil, were infected, at phenological phases of veraison and ripening, by a conidial suspension of Aspergillus carbonarius to control ochratoxin A production and trans-resveratrol- and epsilon-viniferin-induced synthesis as affected by the soil lime content. Chlorosis occurrence was evaluated by a visual rating scale at veraison, and the leaves from vines growing on the calcareous soil showed the typical yellowing, whereas those grown on the neutral soil were dark green. Berry mineral element yield was recorded at veraison and ripening. Infection symptoms on berries were more severe at ripening in bunches collected from vines grown in calcareous soil. Ochratoxin A concentration increased at phenological phase of veraison in berries harvested from vines cultivated in calcareous soil. A. carbonarius enhanced trans-resveratrol and epsilon-viniferin production in infected berries more than in the control samples. Moreover, at veraison their concentration in the berries collected from vines grown in calcareous soil was greater than that recorded from berries collected from vines grown in the neutral soil. The lowest symptom severity was observed on berries containing the highest copper concentration. 相似文献
106.
107.
108.
The Mauve Stinger Pelagia noctiluca (Forssk?l, 1775). Distribution,Ecology, Toxicity and Epidemiology of Stings. A Review 下载免费PDF全文
The toxicity of Cnidaria is a subject of concern due to its influence on humans. In particular, jellyfish blooms can highly affect human economical activities, such as bathing, fishery, tourism, etc., as well as the public health. Stinging structures of Cnidaria (nematocysts) produce remarkable effects on human skin, such as erythema, swelling, burning and vesicles, and at times further severe dermonecrotic, cardio- and neurotoxic effects, which are particularly dangerous in sensitive subjects. In several zones the toxicity of jellyfish is a very important health problem, thus it has stimulated the research on these organisms; to date toxicological research on Cnidarian venoms in the Mediterranean region is not well developed due to the weak poisonousness of venoms of jellyfish and anemones living in this area. In spite of this, during last decades several problems were also caused in the Mediterranean by stinging consequent to Cnidarian blooms mainly caused by Pelagia noctiluca (Forsskål, 1775) which is known to be the most venomous Mediterranean jellyfish. This paper reviews the knowledge on this jellyfish species, particularly considering its occurrence and toxicity. 相似文献
109.
High tolerance of European plum varieties to plum leptonecrosis 总被引:1,自引:0,他引:1
Luigi Carraro Nazia Loi Paolo Ermacora Ruggero Osler 《European journal of plant pathology / European Foundation for Plant Pathology》1998,104(2):141-145
A 13 year comparative study was carried out on the behaviour of four European and two Japanese plum varieties grown in adjacent rows in an area of northern Italy where plum leptonecrosis is epidemic. Within seven years, 100% of the Japanese plum trees became symptomatically infected. Nine years after planting, five trees of each of the European cvs, which were asymptomatic, were top-grafted with healthy buds of the cv Ozark Premier, which is an indicator for plum leptonecrosis. Based on the results of PCR analysis, DAPI staining and on the reaction of the top-grafted Ozark Premier indicators, 50% of the European plum trees, despite their healthy appearance, were shown to be infected with plum leptonecrosis. The detectable presence and graft transmissibility of the plum leptonecrosis phytoplasma in the asymptomatic European plum trees means that the European plum trees are not resistant to the infection but that they are tolerant. The active presence of a still unknown vector/s in the investigated area is stressed as well as the important role of Prunus domestica L. played in the conservation and spread of plum leptonecrosis. 相似文献
110.