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711.
Tasuku Kato Hisao Kuroda Hideo Nakasone Hirohide Kiri 《Paddy and Water Environment》2007,5(3):189-199
A year-long study on the water quality and hydrology was carried out to investigate the characteristics of the pollutant concentrations
and pollutant removal in a constructed irrigation pond. The pond is part of a circular irrigation system for paddy fields
within Lake Kasumigaura watershed, Japan. The average concentrations of the total nitrogen (TN), chemical oxygen demand (COD),
total phosphorus (TP), and suspended solids (SS) at the pond outlet were 7.4, 8.6, 0.2, and 18.8 mg L−1, respectively. The average removed loads for the same indices were 0.14, 2.47, 0.11, and 24.2 g m−2 day−1, respectively. The percentages of pollutant removals from the inflow loads for the same indices were 3, 26, 42, and 63%,
respectively. The pond discharged the TN loads of 128 kg due to sediments stirred by operation of a pump for April and May.
The average TN removal was 19% from June to August and was smaller than that reported in published literatures (40–50%). Major
reasons were considered to be that the turnover of water in the pond was rapid (86% per day) and that the TN concentration
of inflow water was relatively low (5.9 mg L−1). The percentages of pollutants that flowed into the pond to the outflow loads from the study site were 6.6, 4.8, 1.6, and
1.1% for TN, COD, TP, and SS loads, respectively. The pollutant removal will be increased if the design of the circular irrigation
system is reconsidered to utilize a pollutant removal function in the irrigation pond. 相似文献
712.
Masayuki?Takahashi Takeshi?Yamamoto Sanae?Kato Kunihiko?KonnoEmail author 《Fisheries Science》2005,71(2):405-413
Thermal denaturation of myofibrils from various species of fish was investigated by measuring ATPase inactivation, myosin
aggregation, myosin subfragment-1 (S-1) and rod denaturation rates as studied by chymotryptic digestion. Decrease in monomeric
myosin (myosin aggregation) was always faster than the ATPase inactivation for all myofibrils tested. The relative denaturation
rate of rod to that of S-1 differed from species to species. Preceded denaturation of rod was observed with some species,
and the opposite was true with other species. The denaturation pattern was explained by the different magnitude of S-1 stabilization
by F-actin in myofibrils at low salt medium. Myofibrils which receive a great stabilization by F-actin as studied by ATPase
inactivation showed the preceded rod denaturation pattern, and vice versa. S-1 portion, not F-actin, determined the different
stabilization of S-1 by F-actin in myofibrils. 相似文献
713.
Tohya Yasuda Kazuyoshi Komeyama Keitaro Kato Yasushi Mitsunaga 《Fisheries Science》2012,78(2):229-235
We investigated the usefulness of acceleration loggers in aquaculture by examining net-cage use and metabolic rates in red
sea bream, Pagrus major. First, the fish’s metabolic rate (mg O2 kg−1 min−1) was measured with the logger in a swim tunnel at designated water velocities. We found that metabolic rate could be expressed
by using a linear regression model of the activity rate index (unitless min−1) derived from acceleration data. Using this equation, the field metabolic rates of three fish in a net cage were monitored
and were estimated at 14.1–15.0 kcal kg−1 day−1. The results suggested that 15–19% of energy from satiation feeding ration was consumed for metabolism and activity in the
net cage. The loggers showed orderly net-cage use by the fish. Tagged individuals used the whole cage from surface to bottom,
but individual fish that preferred the surface area rarely used the bottom, and vice versa. Metabolic rate increased significantly
with distance of the fish from their preferred depths. The logger provided information on the physiological and behavioral
responses of fish in a given breeding system, and its use should contribute to the design of practical aquaculture systems. 相似文献
714.
Fish meal replacement by soy protein from soymilk in the diets of red sea bream (Pagrus major) 下载免费PDF全文
A. Biswas H. Araki T. Sakata T. Nakamori K. Kato K. Takii 《Aquaculture Nutrition》2017,23(6):1379-1389
Six isoenergetic diets were formulated as follows: fish meal (FM) 700 g kg–1 (control, C), FM 300 g kg–1 + soy protein concentrate 300 g kg–1 (SPC), FM 300 g kg–1 + enzyme‐treated SPC 300 g kg–1 (ESC), FM 170 g kg–1 + soy protein isolate 300 g kg–1 (SPI), FM 160 g kg–1 + enzyme‐treated SPI 300 g kg–1 (ESI) and FM 150 g kg–1 + conglycinin 300 g kg–1(CG). Forty fish (3.9 g) were randomly distributed into each of eighteen 300‐L tanks, fed twice daily until satiation for 8 weeks. The final body weight, specific growth rate and condition factor did not show significant differences among the fish fed with diets C, SPC, ESC and ESI (p > .05). The survival was significantly lower in fish fed with diets SPI and CG. Feed efficiency was significantly higher in fish fed with diets SPC and C than in fish fed with other diets (p < .05). There were no significant differences in nutrients retention efficiencies in fish fed with diets C, SPC, ESC and ESI. A significantly higher phosphorus retention efficiency in fish fed with soymilk protein diets resulted in lower phosphorus discharge to the environment (p < .05). These results suggest that the soymilk proteins can comfortably replace 570–770 g FM kg–1 diet of red sea bream juvenile, which will ensure significant ecological benefits through reducing phosphorus load to the environment. 相似文献