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151.
Beata?Krasnodebska-OstregaEmail author Krzysztof?Dmowski Ewa?Stryjewska Jerzy?Golimowski 《Journal of Soils and Sediments》2005,5(2):71-73
Background, Goal and Scope The aim of this study was to check the concentration of some elements in water samples collected near Pb-Zn mining and smelting works and comparison of the obtained data with results achieved for sediment samples originated from the same reservoirs. Objective Here, 8 water samples and 3 bottom sediments collected from water reservoirs in the vicinity of 3 big Polish Pb-Zn smelters were analysed.Methods Water analysis was performed after filtration through a 0.45 µm filter and pH adjustment to 2. For decomposition of dried sediment samples, microwave assisted digestion with total dissolution of silicate matrix was applied. The elements studied were determined using ICP-MS and ICP-OES methods. Results and Discussion The concentrations of most studied elements in water samples were on the 0.X µg/L level, while only the contents of Tl, As, Mn, Cd, Pb and Sb in two water reservoirs were above the limits established for drinking water. The content of studied metals in sediments was in a wide range from X mg/kg (Se and Sb) to X000 mg/kg (Pb and Zn).Conclusions and Recommendation. The study indicates that the impact of Tl, As, Cd, Cu, Mn, Pb, Zn, Se and Sb on bottom sediments is much more extensive than on the water in ponds located in the vicinity of a post-flotation waste heap. Monitoring of surface and underground waters, if limited only to the dissolved elements, can lead to faulty conclusions about environmental pollution. The bottom sediments mainly contain easily mobilised phases, and water-sediment equilibrium could be changed easily. 相似文献
152.
In this work, a relaxation term was added to the convective boundary condition to increase the accuracy of the transient bound
water diffusion modeling in wood. The implemented term accounts for a relaxation time constant in the equilibrium moisture
content. The inverse finite element analysis approach was used to determine the values of all coefficients of the modified
diffusion model. This procedure was performed for beech wood (Fagus sylvatica L.) in the radial and longitudinal directions. The experimental data obtained by Perré et al. (2007) for transient diffusion configurations were used here. The accurate control of moist air parameters and the improved procedure
for mass measurements of a sample during sorption experiments were used. The influence of the modification of the boundary
condition on accuracy of diffusion modeling was analyzed. 相似文献
153.
Gorinstein S Leontowicz M Leontowicz H Jastrzebski Z Drzewiecki J Namiesnik J Zachwieja Z Barton H Tashma Z Katrich E Trakhtenberg S 《Journal of agricultural and food chemistry》2006,54(11):4022-4027
The aim of this investigation was to evaluate the dose-dependent influence of commercial garlic on rats fed cholesterol-containing diets. It was found that commercial garlic contains high concentrations of dietary fibers, microelements, and total polyphenols, and its total antioxidant capacity as determined by two independent assays [1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azinobis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS)] was similar to that of the original garlic samples. Wistar rats (35) were randomly divided into five diet groups, named control, Chol, Garlic500, Garlic750, and Garlic1000. Control rats were fed basal diet (BD), which included wheat starch, casein, soybean oil, and vitamin and mineral mixtures. To the BD of the Chol group was added 1% of cholesterol. To the BD of the other three groups (Garlic500, Garlic750, and Garlic1000) were added 1% of cholesterol and commercial garlic equal to 500, 750, and 1000 mg of raw garlic per kilogram of animal weight. After 4 weeks of the experiment only in rats from the Garlic500 group were a significant hindering in the rise in plasma lipids and also a significant hindering in a decrease of plasma antioxidant activity registered. A significant decrease in plasma circulating fibrinogen and an increase in the clotting time were found in the same group of rats (P < 0.05 in both cases). The fibrinogenolytic effect of garlic diets was visualized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. In the fibrinogen fraction of Garlic500 the 66, 24, and 14 kDa protein bands were detected with weaker protein intensity than in the corresponding ones in the Garlic750 and Garlic1000 diet groups. In conclusion, the positive influences of commercial garlic on plasma lipids, proteins, antioxidant activity, and some indices of blood coagulation are dose-dependent. Therefore, commercial garlic (Elena, Zelazków, Poland) could be a valuable component of atherosclerosis-preventing diets only in optimal doses. 相似文献
154.
Elżbieta J. Bielińska Barbara Futa Aleksandra Ukalska-Jaruga Jerzy Weber Szymon Chmielewski Sylwia Wesołowska Agnieszka Mocek-Płóciniak Krzysztof Patkowski Lilla Mielnik 《Journal of Soils and Sediments》2018,18(8):2682-2691
Purpose
The aim of this study was to determine the mutual relations between polycyclic aromatic hydrocarbons (PAHs) originated from atmospheric emissions and enzymatic activity and humic substances in soils at differently urbanized area, on an example of the Lublin city, east Poland.Materials and methods
The chosen areas represented three differently urbanized environments: old tenement houses and modern residential blocks, mixture of different building and rural landscape, and typical rural environment with smallholding farms, respectively. On each of the urban, suburban, and rural areas, one representative plot was chosen on fallow lands classified as luvisol derived from loess. The soil samples were collected from the top 25 cm layer. The following properties were determined: pH, organic carbon, total nitrogen, humic and fulvic acids, PAHs content (14 PAHs from US EPA list), and the activities of the following enzymes: dehydrogenases, acid phosphatase, alkane phosphatase, protease, and urease.Results and discussion
Higher contents of organic C and total N were found in the rural soil samples. The share of humic acid was similar in all soils investigated, ranging from 19.38 to 25.27%, while fulvic acid values differ significantly between urban and rural areas. The urban soils indicated much lower share of fulvic acids (9.78–10.99%) than those of rural (29.02–29.32%). Consequently, the values of the CHA:CFA ratio of the urban soil were approximately two times higher than those of the rural soil. The results showed that both the rate of humification and the activity of dehydrogenases, acid phosphatase, alkaline phosphatase, and proteases in the soils increased in the following sequence: urban < suburban < rural.Conclusions
The results showed that an increase of PAHs in the urbanized areas affect other soil properties. The phenanthrene/anthracene and fluoranthene/pyrene ratios pointed to coal combustion as the principal source of PAHs in the investigated soils. The PAH content in the urbanized area inhibit humification processes in the soil and the activity of dehydrogenases, acid phosphatase, alkaline phosphatase, and proteases.155.
Advocating a need for suitable breeding approaches to boost integrated pest management: a European perspective
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Jay Ram Lamichhane Edward Arseniuk Piet Boonekamp Jerzy Czembor Veronique Decroocq Jérome Enjalbert Maria R Finckh Małgorzata Korbin Mati Koppel Per Kudsk Akos Mesterhazy Danuta Sosnowska Ewa Zimnoch‐Guzowska Antoine Messéan 《Pest management science》2018,74(6):1219-1227
Currently, European farmers do not have access to sufficient numbers and diversity of crop species/varieties. This prevents them from designing cropping systems more resilient to abiotic and biotic stresses. Crop diversification is a key lever to reduce pest (pathogens, animal pests and weeds) pressures at all spatial levels from fields to landscapes. In this context, plant breeding should consist of: (1) increased efforts in the development of new or minor crop varieties to foster diversity in cropping systems, and (2) focus on more resilient varieties showing local adaptation. This new breeding paradigm, called here ‘breeding for integrated pest management (IPM)’, may boost IPM through the development of cultivars with tolerance or resistance to key pests, with the goal of reducing reliance on conventional pesticides. At the same time, this paradigm has legal and practical implications for future breeding programs, including those targeting sustainable agricultural systems. By putting these issues into the context, this article presents the key outcomes of a questionnaire survey and experts' views expressed during an EU workshop entitled ‘Breeding for IPM in sustainable agricultural systems’. © 2017 Society of Chemical Industry 相似文献
156.
Michael Heym Ricardo Ruíz-Peinado Miren Del Río Kamil Bielak David I. Forrester Gerald Dirnberger Ignacio Barbeito Gediminas Brazaitis Indrė Ruškytkė Lluís Coll Marek Fabrika Lars Drössler Magnus Löf Hubert Sterba Václav Hurt Viktor Kurylyak Fabio Lombardi Dejan Stojanović Jan Den Ouden Renzo Motta Maciej Pach Jerzy Skrzyszewski Quentin Ponette Géraud De Streel Vit Sramek Tomáš Čihák Tzvetan M. Zlatanov Admir Avdagic Christian Ammer Kris Verheyen Buraczyk Włodzimierz Andrés Bravo-Oviedo Hans Pretzsch 《Annals of Forest Science》2017,74(3):63