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21.
Tapani Hirvonen Joni Orava Niko Penttinen Katri Luostarinen Markku Hauta-Kasari Mika Sorjonen Kai-Erik Peiponen 《Wood Science and Technology》2014,48(5):995-1003
In this study, a comprehensive spectral image database of Nordic sawn timbers for public use was measured. Economically significant Finnish wood species birch (Betula sp.), Norway spruce (Picea abies) and Scots pine (Pinus sylvestris) were chosen for inclusion in the database. The total of samples was 107 containing heartwood, sapwood, decayed wood, blue stain, mold, resin, early wood, late wood, knots, cracks, pith, reaction wood and bark. Board and crosscut samples were measured in frozen, melted and room-dried conditions. The reflectance of samples was measured over a 300- to 2,500-nm wavelength range. Additionally, the photoluminescence of samples excited by an ultraviolet B light source was measured. The spot size used was 250 μm with an 80 mm \(\times \) 200 mm imaging area, and produced all in all 44 million spectra. In this paper, examples of the possibilities of this spectral image database as a means of detection of the spatial distribution of aromatic lignin and the moisture content (MC) of nonfrozen timber were introduced and provided. From the results, it was found that it was possible to detect the lignin distribution from spectral images, and simple and robust methods for wood MC estimations were also introduced. 相似文献
22.
23.
Aregu Amsalu Aserse Daniel Markos Genet Getachew Markku Yli-Halla Kristina Lindström 《Archives of Agronomy and Soil Science》2020,66(4):488-501
ABSTRACTWhile pulses are staple food-legumes in Ethiopia, their productivity is low due to low soil fertility. Elite rhizobial strains that significantly increased shoot dry weight and nitrogen (N) contents of common beans and soybeans in greenhouse were selected for two-year field trials to evaluate their effect on yields of the pulses in the field. Each pulse had six treatments, namely four rhizobial inoculants, uninoculated control, and synthetic N fertilizer. In the drought-affected year 2015, inoculated pulses tolerated moisture stress better than non-inoculated controls. Inoculation was conducive to higher or equivalent yields compared to synthetic N fertilizer. At Halaba, bean inoculated with strain HAMBI3562 gave the highest grain yield (1500 ± 81 kg ha?1; mean±SE) while the control yielded only 653 ± 22 kg ha?1. At Boricha, HAMBI3570 gave a grain yield (640 ± 35 kg ha?1) comparable to synthetic N. When rainfall was optimal in 2016, inoculation with HAMBI3562 and HAMBI3570 gave grain yields (around 4300 kg ha?1) equivalent to synthetic N. With soybean, strain HAMBI3513 produced consistently higher or comparable biomass and grain yields compared to synthetic N. In conclusion, HAMBI3562 and HAMBI3570 for beans and HAMBI3513 for soybeans can serve as inoculants for areas having similar conditions as the test areas. 相似文献
24.
Eurola M Hietaniemi V Kontturi M Tuuri H Pihlava JM Saastamoinen M Rantanen O Kangas A Niskanen M 《Journal of agricultural and food chemistry》2003,51(9):2608-2614
The cadmium (Cd) contents of oats (Avena sativa L.) in Finland were examined over a 3 year period in three types of trials: official variety, organic vs conventional cultivation, and nitrogen fertilization trials. Large seasonal and regional variations were found in the Cd concentrations. In official variety trials, the mean Cd contents in 1997, 1998, and 1999 were 0.046, 0.029, and 0.052 mg kg(-1) dry weight (dw), respectively, ranging from 0.008 to 0.120 mg kg(-1) dw. The concentrations were generally well below the maximum permitted level of 0.100 mg kg(-1) fresh weight. No significant differences were found between the organic and the conventional cultivation techniques. Nitrogen (N) fertilization increased the Cd contents of oats especially at high nitrogen rates (160 kg N hectare(-1) (ha)). Significant cultivar differences (p < 0.001) were determined in all trials. Cultivars Salo and Kolbu had consistently higher contents, and Belinda and Roope had lower Cd contents among the different growing conditions. Hence, it is possible to cultivate and develop oat cultivars less likely to accumulate Cd. 相似文献
25.
Antioxidant activity of knotwood extractives and phenolic compounds of selected tree species 总被引:1,自引:0,他引:1
Willför SM Ahotupa MO Hemming JE Reunanen MH Eklund PC Sjöholm RE Eckerman CS Pohjamo SP Holmbom BR 《Journal of agricultural and food chemistry》2003,51(26):7600-7606
The antioxidant potency and the radical scavenging capacity of superoxide and peroxyl radicals were assessed for 13 hydrophilic knotwood extracts of commercially important wood species, or fractions thereof, as well as for five pure wood-derived lignans and the flavonoid taxifolin. The chemical composition of the knotwood extracts was determined by gas chromatography combined with mass spectrometry. Most of the investigated wood species were rich in hydrophilic extractives (10-20% of the dry wood) with one or a few compounds dominating in each extract. All extracts had a high antioxidative potency and/or radical scavenging capacity as compared to the well-known antioxidants Trolox and butylated hydroxyanisole. The pure wood-derived lignans and taxifolin also had a high antioxidative potency and/or radical scavenging capacity. However, the antioxidant potency and/or radical scavenging capacity of several of the hydrophilic knotwood extracts were higher than that of the dominating compounds in pure form. 相似文献
26.
In order to respond to global competition challenges, the wood-processing industry in Finland and elsewhere is outsourcing
roundwood harvesting to harvesting contractors. The industry also seeks to negotiate with fewer, larger and more diverse contractor
enterprises. The weak profitability, liquidity and solvency of harvesting contractors and the consequent difficulty in hiring
qualified machine operators make networking and enterprise growth a complicated process. Financial data of 1,060 Finnish wood
harvesting contractors from the period 2001 to 2007 were studied using the ‘closing of the accounts’ data. The material represents
most of the full-time contractors. For 2007 net profit was about 6%, credit share of turnover over 50% and median financial
reserve €18,000. High machine depreciation and interest expenses together with low solidity make it difficult for small enterprises
to absorb seasonal variations and to cope with recessions. Profitability varies considerably amongst smallest enterprises,
which most often are sole-operator enterprises. Moreover, even the median profit of the smallest enterprises tends to be negative,
which means that enterprise capital will be consumed and many enterprises are at risk of failure. Larger enterprises are more
likely to be limited liability companies. Their median profit is clearly positive and the profit varies relative little between
enterprises. 相似文献
27.
Willow buffer strips are a promising vegetated filter for the reduction of non-point source pollution from agricultural land
to watercourses resulting from the rapid growth of shoots and from the large amount and distribution of roots. A greenhouse
experiment tested the hypothesis that a new planting method, planting cuttings horizontally, exhibited more biomass production
and more effective filter than did planting cuttings vertically. Due to the different times taken for shoots break through
the soil surface, the summed height of all shoots of horizontally planted cuttings was significantly smaller than that of
the vertical ones at the beginning of the growth period. The difference in the height of all of the shoots between planting
orientations decreased with time. After 16 weeks growth, the biomass of the stem, leaves and fine roots was not affected by
the planting orientation. The coarse root biomass was larger in the horizontal treatments and decreased with increased density.
The total biomass, as well as the biomass of stem or leaves, of each treatment, increased with increased planting density.
The individual plant biomass, as well as that of the stem or leaves, decreased with increased planting density. Compared with
the unplanted control treatment, the planted treatments significantly reduced the total-N, NO3-N, PO4-P and SO4-S leaching. The planting orientation did not affect the nitrate leaching. The horizontally planted cuttings were slightly
more effective for reducing the SO4-S leaching and the vertically planted cuttings were slightly more effective for reducing the PO4-P leaching. Lower PO4-P leaching was observed only with higher planting density. With regard to the horizontal planting method, further studies
are needed to explore the influence of different willow clones, the size of cuttings, pre-planting treatments, planting geometry
(configuration) and soil conditions on survival, the number of shoots produced, the biomass production and the amount and
distribution of roots. 相似文献
28.
The objective of this study was to investigate possible ways of mobilizing residual fertilizer P as a result of local pH elevation caused by urea hydrolysis. The response of water-soluble P (Pw) and dissolved organic C (DOC) to urea hydrolysis was monitored in three cultivated soils and at two P levels for up to 127–135 d and compared with corresponding changes in soils limed with Ca(OH)2. Hydrolysis of urea was complete in 8–15d during which soil pH increased by 1–1.5 units at the maximum. Subsequently, the pH decreased to or below the original level owing to nitrification. Mobilization of soil P was enhanced substantially in parallel with the increase in pH, the peak Pw occurring simultaneously with the highest pH value. In all urea-treated soils, Pw remained at an elevated level for at least 60d. As compared to urea, elevation of soil pH with Ca(OH)2 had only a minor and inconsistent influence on Pw. In mobilization of soil P, the urea-induced increase in pH and a simultaneous production of NH4+ ions proved to be superior to liming with Ca(OH)2. It was hypothesized that when an acid soil is amended with urea, phosphate is first displaced by OH? ions, resulting in elevated solution P concentrations. A simultaneous dissolution of organic matter contributes to the persistence of high P concentration by competition for sorption sites on Fe and Al oxides, and thus retards the resorption of P. 相似文献
29.
Mesele Negash Mike Starr Markku Kanninen Leakemaraiam Berhe 《Agroforestry Systems》2013,87(4):953-966
Coffee, Coffea arabica L., which is native to Ethiopia, is the world’s most widely traded tropical agricultural commodity. While much is known about the productivity and management of coffee for coffee beans little attention has been given to the plants overall biomass production and carbon sequestration. The objective of this study was to develop and evaluate allometric equations for estimating the aboveground biomass of C. arabica plants growing in indigenous agroforestry system in the Rift Valley escarpment of south-eastern Ethiopia. Coffee plays an important role in providing income and in sustaining these productive systems. Biomass harvesting of 31 plants with 54 stems was carried out in a 40 km2 area varying in elevation from 1,500 to 1,900 m. The stem accounted for most (56 %) of plant biomass, followed by branches (39 %) and twigs plus foliage (5 %). Plant mean biomass was 22.9 ± 15.8 kg. Power equations using stem diameter measured at either 40 cm (d 40) or at breast height (d, 1.3 m) with and without stem height (h) were evaluated. The square power equation, $ Y \; = \; b_{ 1} d_{ 40}^{ 2} $ , was found to be the best (highest ranked using goodness-of-fit statistics) for predicting total and component biomass. The reliability of the prediction decreased in the order: stem > branches > twigs plus foliage. A cross-validation procedure showed that equation parameterization was stable and coefficients reliable. Our parameterized square power equation for total aboveground biomass was also found to be better than the equations parameterized by Hairiah et al. (Carbon stocks of tropical land use systems as part of the global C balance: effects of forest conversion and options for clean development activities, International Centre for Research in Agroforestry, Bogor, 2001) and Segura et al. (Agroforest Syst 68:143–150, 2006) for C. arabica grown in agroforestry systems, confirming the importance of parameterization of allometric equations with site specific data when possible. 相似文献
30.
Greta Faccio Laura FlanderJohanna Buchert Markku SaloheimoEmilia Nordlund 《Journal of Cereal Science》2012,55(1):37-43
Various enzyme families such as sulfhydryl oxidase have been successfully applied to bread production although their mechanism of action has not been fully described yet. In this study, we investigated the effects of the recently characterized fungal sulfhydryl oxidase AoSOX1 in fresh and frozen dough alone and in combination with ascorbic acid. The addition of AoSOX1 to an additive-free dough resulted in a weaker and more extensible dough while opposite effects were detected in the presence of ascorbic acid. The hardening of the doughs registered upon the combined use of AoSOX1 and ascorbic acid was dependent on the amount of enzyme used and not on the amount of ascorbic acid. The ability of the sulfhydryl oxidase to enhance the effects of the ascorbic acid system suggests their combined use as a valuable tool to stabilize the structure of fresh and frozen dough. 相似文献