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21.
Two acid rain experiments were conducted, one at Oulu using transplanted seedlings of Picea abies and Pinus sylvestris, and the other with adult pines at Kevo where test plots were designated in a natural mixed stand of Pinus sylvestris and Betula tortuosa. The acid solution was made by adding H2SO4 and HNO3 (vol:vol 2:1, pH adjusted to 3 and 4) to clean water.The Oulu experiment was carried out from 1986 to 1989, and Kevo from 1985 to 1989. No visible injuries related directly to the acid rain treatment could be observed after 3 yr of the experiments, but microscopic examination revealed significant changes in the structure and morphology of the needles. The conifer seedlings treated at pH 3 had significant amounts of scattered CaSO4 crystallites and characteristic piles and bows on the needle surfaces, as detected with EDS. The number of CaSO4 crystallites was higher on the surfaces of the spruce needles than those of the pine needles. The current needles had more crystallites than the previous year's needles.  相似文献   
22.
Two Finnish agricultural soils (peat soil and loamy sand) were exposed to four freeze-thaw cycles (FTC), with a temperature change from −17.3±0.4 °C to +4.1±0.4 °C. Control cores from both soils were kept at constant temperature (+6.6±2.0 °C) without FTCs. Soil N2O and CO2 emissions were monitored during soil thawing, and the effects of FTCs on soil microbes were studied. N2O emissions were extremely low in peat soil, possibly due to low soil water content. Loamy sand had high N2O emission, with the highest emission after the second FTC. Soil freeze-thaw increased anaerobic respiration in both soil types during the first 3-4 FTCs, and this increase was higher in the peat soil. The microbial community structure and biomass analysed with lipid biomarkers (phospholipid fatty acids, 3- and 2- hydroxy fatty acids) were not affected by freezing-thawing cycles, nor was soil microbial biomass carbon (MIB-C). Molecular analysis of the microbial community structure with temperature gradient gel electrophoresis (TGGE) also showed no changes due the FTCs. These results show that freezing and thawing of boreal soils does not have a strong effect on microbial biomass or community structure.  相似文献   
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Water, Air, & Soil Pollution - In the present work we studied the role of humic acids in the heavy metal–soil interaction after the addition of different amounts of humic acids to a soil...  相似文献   
24.
OBJECTIVE: To detect monocarboxylate transporters (MCTs) in canine RBC membranes and to determine the distribution of lactate between plasma and RBCs. SAMPLE POPULATION: Blood samples obtained from 6 purpose-bred Beagles. PROCEDURES: Monocarboxylate transporter isoforms 1, 2, 4, 6, 7, and 8 and CD147 were evaluated in canine RBCs by use of western blot analysis. Lactate influx into RBCs was measured as incorporation of radioactive lactate. RESULTS: 2 MCT isoforms, MCT1 and MCT7, were detected in canine RBC membranes on western blot analysis, whereas anti-MCT2, anti-MCT4, anti-MCT6, and anti-MCT8 antibodies resulted in no signal. No correlation was found between the amount of MCT1 or MCT7 and lactate transport activity, but the ancillary protein CD147 that is needed for the activity of MCT1 had a positive linear correlation with the rate of lactate influx. The apparent Michael is constant for the lactate influx in canine RBCs was 8.8 +/- 0.9mM. Results of in vitro incubation studies revealed that at lactate concentrations of 5 to 15mM, equilibrium of lactate was rapidly obtained between plasma and RBCs. CONCLUSIONS AND CLINICAL RELEVANCE: These results indicated that at least half of the lactate transport in canine RBCs occurs via MCT1, whereas MCT7 may be responsible for the rest, although an additional transporter was not ruled out. For practical purposes, the rapid equilibration of lactate between plasma and RBCs indicated that blood lactate concentrations may be estimated from plasma lactate concentrations.  相似文献   
25.
The effects of nutrient loading (NLOAD) on the frost hardening and dehardening of Picea abies (L.) Karst. seedlings were investigated under nursery conditions. Before NLOAD, second-year container seedlings were either short-day (SD) treated for 3 weeks in July or left for the natural photoperiod (CO). By mid-September, after 5 weeks of NLOAD, the fertilization of three foliar nutrient concentration levels (low = L-SD, medium = M-SD, and high = H-SD) for the SD-treated seedlings and one (medium = M-CO) for the CO-seedlings was completed. The NLOAD resulted in foliar nitrogen concentration 10.6, 16.1, 22.3, and 17.5 g kg−1 for L-SD, M-SD, H-SD and M-CO seedlings, respectively. The NLOAD had no effects on the morphology or dry mass variables of the seedlings, while SD-treatment reduced the dry mass of shoots, but not that of roots. The frost hardiness (FH) of different batches of the seedlings was assessed by the visual scoring of damage in their needles, stems and buds after their controlled exposure to freezing during frost hardening and dehardening. The low nutrient concentration in the SD-treated seedlings (L-SD seedlings) resulted in poor FH, to an even lower extent than that of the M-CO seedlings. The NLOAD did not affect the dehardening of the seedlings at the end of the freezer storage in the following spring.  相似文献   
26.
Barley and malt starches were compared with respect to their lipid content and composition. The starch lipids were first fractionated into internal and surface lipid fractions followed by lipid class and fatty acid analyses of each fraction. Barley starch contained 13 mg/g lipids, of which 9.3 mg were internal lipids and 3.7 mg were surface lipids. The total lipid content of malt starches varied between 11 and 13 mg/g of starch. However, malt starch contained only 1 mg of surface lipids; therefore, the internal lipid contents were as high as or even higher than those in the corresponding fraction of barley starch. Lipid class analyses suggested that the ability for hydrolysis of starch surface lipids was increased in malt. The hydrolysis occurred during the malting or the isolation process, resulting in reduced surface lipid content in malt starch. However, no reduction in the portion of polyunsaturated fatty acids was seen; therefore, lipid oxidation could not have been responsible for the lower content of malt starch surface lipids. Also, not only was the content of starch internal lipids higher in malt, but the composition of these lipids was different when compared to barley starch. The increase in starch internal lipids during malting may be due to transportation and reacylation of free fatty acids that had been liberated by hydrolysis from surface lipids.  相似文献   
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This paper provides an analysis on the integration of prices for imported coniferous pulpwood and sawlogs, and respective domestic stumpage prices in the Finnish wood market. Eight real price series were investigated during 2002–2014 using monthly observations. The bounds testing approach by Pesaran et al. [(2001) Bounds testing approaches to the analysis of level relationships. J Appl Econom. 16: 289–326. doi:10.1002/jae.616], indicates there are long-run relationships between prices of domestic and imported wood. For more detailed information, the vector error correction model (VECM) approach was used. Estimation of a system with all eight prices with interpretable results did not succeed; therefore, we estimated models for prices of sawlogs and for pulpwood separately. For sawlogs, two co-integrating vectors, one for pine and one for spruce, were found. For pulpwood prices, one co-integrating vector was identified. The estimated VECMs confirm the results of bounds testing approach, suggesting that causation in the Finnish wood market runs from domestic prices to prices of imported wood. We conclude that prices of domestic and imported coniferous logs and pulpwood are closely connected. The question of full integration remains open, as border prices and stumpage prices by definition differ, at least, by logging and transportation costs.  相似文献   
30.
The effects of chlorine water on mesophyll cells of Scots pine (Pinus sylvestris) were studied with light and electron microscopy. The treatment caused necrotic flecks formed by collapsed cells. Less injured cells showed increase in number of plastoglobuli, swelling of the thylakoids and vacuolization of the cytoplasm.  相似文献   
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