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排序方式: 共有249条查询结果,搜索用时 15 毫秒
241.
242.
Eiichi TAKASU Humiei YAMADA Nagao SHIMADA Yoshiaki YOSHIDA Masahiko SAIGUSA 《Soil Science and Plant Nutrition》2006,52(2):251-251
(pp. 1–7)
Application of phosphogypsum PG and limestone to Andisol were compared in terms of their effects on the growth and uptake of Ca in Komatsuna Brassica rapa L. cv. Natsurakuten. The studies were carried out in soil pot cultures, and both PG and limestone were applied to the Andisol at the rates of 0, 0.30, 0.75, 1.50 g kg−1 in the form of CaO.
Application of phosphogypsum PG and limestone to Andisol were compared in terms of their effects on the growth and uptake of Ca in Komatsuna Brassica rapa L. cv. Natsurakuten. The studies were carried out in soil pot cultures, and both PG and limestone were applied to the Andisol at the rates of 0, 0.30, 0.75, 1.50 g kg
- 1)
Limestone application resulted in an increase in the soil pH. On the other hand, no change was observed in the case of PG application at pH 6.1 ± 0.1 regardless of the application rate. Both soil EC and water-soluble Ca increased in proportion to the PG application rate, and this increase was approximately 5 times greater than that observed when limestone was applied at 1.50 g kg
−1 . The w-Ca/ex-Ca ratio (water-soluble Ca: 1 M acetic acid-extractable Ca) was clearly increased from 0.12 up to 0.26 in PG, while the value was slightly decreased from 0.12 to 0.05 in limestone.
243.
Hiroki Nakayama Tsukasa Nagamine Nagao Hayashi 《Genetic Resources and Crop Evolution》2005,52(7):863-868
To clarify the geographic variation and isolate specificity in blast resistance, 20 cultivars of foxtail millet (Setaria italica (L.) P. Beauv.) originating from Eurasia were examined for their resistance using 11 Japanese Setaria isolates of blast fungus. Cultivars from the countries east of Pakistan generally showed resistance to most of the 11 fungus
isolates, whereas those from the countries west of Afghanistan indicated higher susceptibility. The origin of this geographical
regularity was discussed in relation to the deficiency or specificity of relevant resistance gene(s). No identical reaction
pattern was observed among cultivars, indicating their highly distinctive isolate specificity. The virulence of isolates was
also diverse, since only 2 out of 10 virulent isolates were identical for their reaction patterns. Preliminary genetic analysis
of blast resistance to four fungus isolates suggests that they are governed by more than two dominant genes. 相似文献
244.
Yasuo Iimura Daichi Tanaka Seiya Nagao Nobuhide Fujitake Toshiyuki Ohtsuka 《Soil Science and Plant Nutrition》2020,66(3):415-420
ABSTRACT The stability of black soil carbon in the deep layers of Japanese volcanic ash soil (i.e., buried A horizons) is often explained by its unique chemical (molecular structure) and physical (associated with short-range-order minerals) recalcitrance. However, the stability of black soil C in buried A horizons may be changed by labile C supply for soil microbes. Here, we hypothesized that the mineralization of black soil C in buried A horizons of Japanese volcanic ash soil could be easily accelerated by a supply of labile C (i.e., a priming effect; PE). To test our hypothesis, we investigated the direction and magnitude of the PE with a buried A horizon in Japan using 13C-labeled glucose (2.188 atom %) in a short-term (21 days) incubation study. We also investigated the effect of mineral nitrogen (N), which could contribute to microbial activity in this incubation study. We found that a positive PE occurred by glucose supply with (182%) or without (181%) mineral N input over the 21-day incubation, and its values were very similar to the PE ratios previously reported in other deep soils. The estimated mean residence time (MRT) of black soil C considering PE was clearly accelerated by glucose supply, regardless of mineral N input, compared with the initial soil MRT. These results strongly support our hypothesis that the mineralization rate of black soil C in buried A horizons is easily accelerated by a labile C supply, and it also demonstrates important implications for the effects of global warming on buried A horizons (e.g., increased root exudation, fine root biomass supply, and N deposition) in Japanese volcanic ash soils. 相似文献
245.
3维图像处理系统在稻米品质检测中的应用研究 总被引:12,自引:7,他引:12
侯彩云 Seiichi Oshit Yasuhisa Seo Yoshinori Kawagoe Toru Torii Kenichi Kudoh Toshiro Higuchi Gabsoo Do 《农业工程学报》2001,17(3):92-95
利用微切片3维图像处理系统对稻米的品质特性进行了探索性的研究。结果表明,借助于3维可视化技术,可以对稻谷的外观品质、营养品质及蒸煮品质等进行更为直观且客观的观察与测定。尤其是在营养成分分布密度的评价、心白米内部组织的分析、蒸煮过程中组织结构变化的观测等方面,取得了传统研究方法难以获得的结果。利用该系统对垩白度的定量化测定,为食品的定量形态学研究开辟了一条新的研究途径。 相似文献
246.
Lack of exposed ice inside lunar south pole Shackleton Crater 总被引:2,自引:0,他引:2
Haruyama J Ohtake M Matsunaga T Morota T Honda C Yokota Y Pieters CM Hara S Hioki K Saiki K Miyamoto H Iwasaki A Abe M Ogawa Y Takeda H Shirao M Yamaji A Josset JL 《Science (New York, N.Y.)》2008,322(5903):938-939
The inside of Shackleton Crater at the lunar south pole is permanently shadowed; it has been inferred to hold water-ice deposits. The Terrain Camera (TC), a 10-meter-resolution stereo camera onboard the Selenological and Engineering Explorer (SELENE) spacecraft, succeeded in imaging the inside of the crater, which was faintly lit by sunlight scattered from the upper inner wall near the rim. The estimated temperature of the crater floor, based on the crater shape model derived from the TC data, is less than approximately 90 kelvin, cold enough to hold water-ice. However, at the TC's spatial resolution, the derived albedo indicates that exposed relatively pure water-ice deposits are not on the crater floor. Water-ice may be disseminated and mixed with soil over a small percentage of the area or may not exist at all. 相似文献
247.
Fujieda M Tanaka T Suwa Y Koshimizu S Kouno I 《Journal of agricultural and food chemistry》2008,56(16):7305-7310
Three new phenolic compounds named whiskey tannins A and B and carboxyl ellagic acid were isolated from commercial Japanese whiskey, along with gallic acid, ellagic acid, brevifolin carboxylic acid, three galloyl glucoses, a galloyl ester of phenolic glucoside, 2,3-(S)-hexahydroxydiphenoylglucose, and castacrenin B. Whiskey tannins A and B were oxidation products of a major oak wood ellagitannin, castalagin, in which the pyrogallol ring at the glucose C-1 position of castalagin was oxidized to a cyclopentenone moiety. These tannins originated from ellagitannins contained in the oak wood used for barrel production; however, the original oak wood ellagitannins were not detected in the whiskey. To examine whether the whiskey tannins were produced during the charring process of barrel production, pyrolysis products of castalagin were investigated. Dehydrocastalagin and a new phenolcarboxylic acid trislactone having an isocoumarin structure were isolated, along with castacrenin F and ellagic acid. However, whiskey tannins were not detected in the products. 相似文献
248.
Ryota Konda Seiichi Ohta Shigehiro Ishizuka Seiko Arai Saifuddin Ansori Nagaharu Tanaka Arisman Hardjono 《Soil biology & biochemistry》2008,40(12):3021-3030
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
249.
Ryuichi Haginoya Kunio Sakai Takashi Komatsu Seiichi Nagao Kenji Yokoyama Toshifumi Takeuchi Ritsuko Matsukawa Isao Karube 《Cereal Chemistry》1997,74(6):745-749
The determination of damaged starch and diastatic activity in flour was studied using a flow-injection analysis (FIA) biosensor system. The system consisted of an oxygen electrode and an immobilized enzyme column containing purified glucoamylase and glucose oxidase immobilized on activated aminopropyl glass beads. The biosensor system has an optimum pH between 6.5 and 7.5 and an optimum temperature of 35°C for glucose measurement. The response of the FIA biosensor was linear up to 1.000 g/L of glucose with a lower detection limit of 0.025 g/L. Each assay took about 20 min, and the system showed good reproducibility (r = 0.998, n = 8). When applied to the measurement of damaged starch and diastatic activity in wheat flour, the results obtained agreed with those obtained using the conventional methods of measurement. This biosensor system is a rapid practical alternative for the measurement of damaged starch and diastatic activity in wheat flour. 相似文献