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441.
442.
Yasuyuki Matsushita In-Cheol Jang Takanori Imai Kazuhiko Fukushima Jeung-Min Lee Hae-Ryong Park Seung-Cheol Lee 《Journal of Wood Science》2011,57(2):161-165
4,8-Dihydroxy-5-methoxy-2-naphthaldehyde (Compound I) was isolated from blackened heartwood of Diospyros kaki and was methylated with diazomethane. Antioxidant and cytotoxic activities of Compound I and two methylated derivatives [4-hydroxy-5,8-dimethoxy-2-(2-oxopropyl)-naphthalene (D-1) and 2-glycidyl-4-hydroxy-5,8-dimethoxy naphthalene (D-2)] were evaluated. Compound I showed higher 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and reducing power than D-1 and D-2. However, D-1 and D-2 exhibited slightly stronger 2,2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)+ (ABTS+) radical scavenging activity than Compound I. Compound I also exhibited stronger cytotoxic activity than D-1 and D-2 against the growth of HT-29 colon cancer cells. The results supported the hypothesis that methylation of naphthalene derivatives slightly increased ABTS+ radical scavenging activity, but significantly decreased DPPH radical scavenging activity, reducing power, and cytotoxic activity. 相似文献
443.
This study was conducted to determine the relation between the dynamic modulus of elasticity and the static modulus of elasticity, and the relation between the dynamic modulus of elasticity and the modulus of rupture of mandarin peel–sawdust composite boards. The result of this study was as follows: There was highly close linear correlation between the dynamic modulus of elasticity and the static modulus of elasticity, modulus of rupture of the mandarin peel–sawdust composite boards with the density of 0.4, 0.5 and 0.6 g/cm3, and the mandarin peel content of 10, 20, 30 and 40%, thus, the static modulus of elasticity and the modulus of rupture can be predicted from the dynamic modulus of elasticity measured by free vibration test using resonance frequency. 相似文献
444.
The changes of fractal dimension ofPicea koraiensis seedlings under different light intensities in natural secondary forests was studied. The results showed that with the change
of light environment, crown characters ofPicea koraiensis seedlings exhibited a greater plastic in lateral number, lateral increment, lateral dry weight, and specific leaf area. The
range of calculated fractal dimensions of seedling crowns was confined between 2.5728 and 2.1036, but maximum of fractal dimension
achieved in term moderate shading and in extreme low light conditions fractal dimension was least.
Foundation item: This paper was supported by the National Natural Science Foundation of China (No.39670152) and Chinese Academy of Sciences.
Biography: ZHOU Yong-bin (1970-), female, Ph. Doctor, lecture in Shenyang Agricultural University, Shenyang 110161, P.R. China
Responsible editor: Song Funan 相似文献
445.
A cytotoxic triterpenoid saponin was isolated from the under-ground parts of Gypsophila pilulifera Boiss.& Heldr. (Caryophyllaceae) naturally grow in the southwestern region of the Turkey. The structures of saponin was elucidated as 3-O-β-D-galactopyranosyl-(1→2)-[β-D-xylopyranosyl-(1→3)]-β-D-glucuronopyranosyl quillaic acid 28-O-β-D-glucopyranosyl-(1→3)-[β-d-xylopyranosyl-(1→4]-α-l-rhamnopyranosyl-(1→2)-β-D-fucopyranosyl ester on the basis of extensive spectral analysis and chemical evidence. The separated triterpenoid saponin was isolated from Gypsophila pilulifera for the first time. The saponin compound displayed significant cytotoxicity against A549 cell line with IC(50) values >16μM. 相似文献
446.
447.
Background:Whey permeate is an effective lactose source for nursery pigs and the most benefits are obtained when pigs are at 7 to 11 kg BW.Altering weaning ages could cause different length of early-weaner phases until 7 kg BW and thus it would influence the dietary need of whey permeate during 7 to 11 kg BW of pigs.This study aimed to evaluate if weaning ages would affect the dietary needs of whey permeate for optimum growth performance of pigs at 7 to 11 kg BW.Methods:A total of 1,632 pigs were weaned at d 21(d 21.2±1.3)or d 25(d 24.6±1.1)after birth.All pigs had a common early-weaner feeds until they reached 7 kg BW.When pigs reached 7 kg BW within a weaning age group,they were allotted in a randomized complete block design(2×4 factorial).Two factors were weaning age groups(21 and 25 d of age)and varying whey permeate levels(7.50%,11.25%,15.00%,and 18.75%).Data were analyzed using the GLM and NLIN procedures of SAS for slope-ratio and broken-line analyses to determine the growth response to whey permeate and optimal daily whey permeate intake for the growth of the pigs weaned at different ages.Results:Pigs weaned at 21 d of age had a common diet for 11 d to reach 7 kg BW whereas pigs weaned at 25 d of age needed 2 d.The G:F of pigs weaned at 25 d of age responded to increased daily whey permeate intake greater(P<0.05)than pigs weaned at 21 d of age.Breakpoints were obtained(P<0.05)at 88 and 60 g/d daily whey permeate intake or 17.0%and 14.4%of whey permeate for G:F of pigs weaned at 21 and 25 d of age,respectively.Conclusion:Pigs weaned at an older age with a short early-weaner phase had a greater growth response to whey permeate intake compared with pigs weaned at a younger age with a long early-weaner phase.Altering weaning ages affected dietary needs of whey permeate for optimum growth performance of pigs from 7 to 11 kg BW. 相似文献
448.
Won-Ho Nam Jin-Yong Choi Seung-Hwan Yoo Min-Won Jang 《Paddy and Water Environment》2012,10(3):197-207
Since predicted changes in climate will modify temperature and rainfall patterns, there are concerns about the potential impacts of these changes on agricultural drought and agricultural water resources management. An agricultural drought is influenced by several factors such as rainfall, soil characteristics, crops, and reservoir water supply and may be defined as the imbalance of water circulation in paddy and water environments. In particular, soil moisture and water supply for reservoir demand are the most direct and important indicators of agricultural drought events. In the past, conventional drought management approaches based on climatic and meteorological observations have been the primary tools used for measuring drought severity. Because of the spatial and temporal variability and multiple impacts of drought, it is necessary to improve tools to determine the onset, severity, spatial extent, and end of the drought conditions. Improved and available data for mapping and monitoring of this phenomenon are also needed. Effective and efficient drought management can be achieved through drought monitoring based on the ability to assess current conditions and provide improved tools to adapt and mitigate the impacts of future changes. In this article, a methodology is developed to support the risk-based decision-making process involved in agricultural drought management using the following four strategies: drought assessment and monitoring, drought forecast and outlook, drought countermeasures, and drought records management. 相似文献
449.
450.
Seven years of performance data from a free surface flow constructed wetland system receiving agricultural runoff were used
to determine treatment performance and to develop regression and wetland design models. Removal rates by the wetland were
21–43.6% for 5-day biochemical oxygen demand (BOD5), 49.0–58.1% for total phosphorous (TP), 24.1–46.0% for total nitrogen (TN), and 57.6–77.8% for total suspended solids (TSS).
First-order area-based rate constant (k
20) values for BOD5 were 15.48 m/year in the early stage of observation and decreased to 12.00 m/year for the stable period. Similar results
were found for TP, for which k
20 values were 18.72 m/year in the early stage and 14.92 m/year for the stable period. For TN, k
20 values in the early stage (21.32 m/year) were slightly lower than those for the stable period (38.02 m/year). Finally, TSS
had values of 132.4 and 172.6 m/year in the early and stable periods, respectively. The low k
20 for BOD5 was not important for nonpoint source pollution control in the constructed wetland because these kinds of wetlands mainly
focus on nitrogen and phosphorus retention. The wetland area and outlet concentration could be approximately predicted using
the first-order kinetic model, but the maturity and hydraulic loading rate should be considered for more accurate prediction. 相似文献