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71.
The addition of a bulking agent achieves the bulking of paper and increases the pore volume. In this study, the effect of adding bulking agents with various alkyl chain lengths (C14, C18, and C22) on the bulk of paper, the sizing performance, and sheet wettability was evaluated. The bulking effect of a bulking agent with a short alkyl chain length (C14) was large, and reduction in the sheet tensile strength was confirmed to be suppressed. Good sheet sizing performance was achieved when a bulking agent was used with an alkyl ketene dimer (AKD). When 0.1% or more of AKD was added, using a bulking agent with a shorter alkyl chain length increased the improvement in the sizing degree. Pyrolysis gas chromatography measurements of the amount of reacted AKD revealed that the addition of a bulking agent increased the AKD content of the sheet. The sheet contact angle measured by the two-liquid method tended to increase with increasing alkyl chain length. However, the sheet contact angle was not directly correlated with the Stöckigt sizing degree. By using 1% ferric chloride (FeCl3) and 2% ammonium thiocyanate (NH4SCN) aqueous solution, which are used for measuring the Stöckigt sizing degree, the time-dependent change in the contact angle on the paper sheet surface was measured to evaluate wettability. The Stöckigt sizing degree of paper sheets was found to be greatly influenced by the sheet wettability by NH4SCN solution. In the case of 2% NH4SCN aqueous solution, different samples exhibited large wettability differences. When 0.2% or less of AKD was added, the effect of the concentration on the contact angle was confirmed to be large at all NH4SCN concentrations.  相似文献   
72.
We investigated spatial structures of N2O, CO2, and CH4 fluxes during a relatively dry season in an Acacia mangium plantation stand in Sumatra, Indonesia. The fluxes and soil properties were measured at 1-m intervals in a 1 × 30-m plot (62 grid points) and at 10-m intervals in a 40 × 100-m plot (55 grid points) at different topographical positions of the upper plateau, slope, and valley bottom in the plantation. Spatial structures of each gas flux and soil property were identified using geostatistical analysis. The means (±SD) of N2O, CO2, and CH4 fluxes in the 10-m grids were 0.54 (±0.33) mg N m−2 d−1, 2.81 (±0.71) g C m−2 d−1, and −0.84 (±0.33) mg C m−2 d−1, respectively. This suggests that A. mangium soils function as a larger source of N2O than natural forest soils in the adjacent province on Sumatra during the relatively dry season, while CO2 and CH4 emissions from the A. mangium soils were less than or consistent with those in the natural forest soils. Multiple spatial dependence of N2O fluxes within 3.2 m (1-m grids) and 35.0 m (10-m grids), and CO2 fluxes within 1.8 m (1-m grids) and over 65 m (10-m grids) was detected. From the relationship among N2O and CO2 gas fluxes, soil properties, and topographic elements, we suggest that the multiple spatial structures of N2O and CO2 fluxes are mainly associated with soil resources such as readily mineralizable carbon and nitrogen in a relatively dry season. The soil resource distributions were probably controlled by the meso- and microtopography. Meanwhile, CH4 fluxes were spatially independent in the A. mangium soils, and the water-filled pore space appeared to mainly control the spatial distribution of these fluxes.  相似文献   
73.
74.
In pine wilt disease, xylem dysfunction occurs in relation to nematode migration and proliferation in host tissue, but the detection accuracy of pinewood nematode (PWN), Bursaphelenchus xylophilus, in pine stem tissue remains unclear. This study describes the use of cryo-scanning electron microscopy (cryo-SEM) and fluorescein-conjugated wheat germ agglutinin (F-WGA) staining to detect PWN. After PWN invasion, the frequency of surface fluorescence in PWN increased in pine stems from the day of inoculation to 3 weeks after inoculation. However, the fluorescence frequency decreased significantly during the advanced disease stage after 5 weeks. Thus, detecting PWN based on fluorescent staining of the nematode body surface coat protein can be misleading when used to examine the correlation between the development of disease symptoms and the nematode population. In contrast, all cut body segments were fluorescent, and their fluorescent components were common in pine-stem cross sections, regardless of the timing after inoculation. In addition, PWN were observed under cryo-SEM only in empty resin canals and this distribution was confirmed by F-WGA staining of PWN cut in a cross section. Thus, PWN detection based on fluorescent staining of surface coat proteins by F-WGA was not reliable in longitudinal sections of pine stems because of changes in nematode stainability during disease progression. To detect PWN in infected plants, we concluded that a combination of both methods is most effective.  相似文献   
75.
Furuta  Ayumi  Mabuchi  Ryota  Tanimoto  Shota 《Fisheries Science》2020,86(4):693-700
Fisheries Science - We investigated the effects of different heating conditions on the texture and extractive compounds of meat derived from each part of the yellowtail Seriola quinqueradiata fish....  相似文献   
76.
Fisheries Science - We detected an earthy/musty off-flavor in the flesh of red sea bream Pagrus major cultured under low saline water conditions using two types of recirculating aquaculture systems...  相似文献   
77.
We previously reported that rhamnan sulfate (RS) purified from Monostroma nitidum significantly suppressed lipopolysaccharide (LPS)-induced inflammation in cultured human vascular endothelial cells. Here, we analyzed the effect of orally administered RS on LPS-induced damage to mouse organs and vascular endothelium. RS (1 mg) was orally administered daily to BALB/c mice, 50 μg of LPS was intraperitoneally administered on day 8, and Evans blue was injected into the tail vein 6 h later. After 30 min, LPS-treated mice showed pulmonary Evans blue leakage and elevated plasma levels of liver damage markers, whereas this reaction was suppressed in LPS + RS-treated mice. Immunohistochemical and Western blot analysis of mouse organs 24 h after LPS treatment showed significant neutrophil infiltration into the lung, liver, and jejunum tissues of LPS-treated mice and high expression levels of inflammation-related factors in these tissues. Expression levels of these factors were significantly suppressed in LPS + RS-treated mice. Analysis of lung glycocalyx showed a significant reduction in glycocalyx in LPS-treated mice but not in LPS + RS-treated mice. Levels of syndecan-4, one of the glycocalyx components, decreased in LPS-treated mice and increased in LPS + RS-treated mice. The current results suggest that orally administered RS protects organs and vascular endothelium from LPS-induced inflammation and maintains blood circulation.  相似文献   
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