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Tropical Animal Health and Production - The South Pacific island countries (SPIC) are among the most vulnerable countries in the world to economic shocks, climate change and natural disasters....  相似文献   
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Wood specific gravity of some tree species in the Garhwal Himalayas,India   总被引:2,自引:2,他引:0  
Estimation of terrestrial biomass depends critically on reliable information about wood specific gravity of forest trees. In recent years, wood specific gravity has become more important when exploring the universality of functional traits of plants and estimating their global carbon stocks. To estimate their specific gravity, wood samples were collected from a total of 34 tree species, 30 from lower elevations and 4 from upper elevations in the Garhwal Himalayas, India. The results show that the average wood specific gravity was 0.631 (ranging between 0.275 ± 0.01 and 0.845 ± 0.03) for the species at lower elevations and 0.727 (ranging between 0.628 ± 0.02 and 0.865 ± 0.02) for the upper elevations. The average wood specific gravity for the upper elevation species was 9.6% greater than that for the species at lower elevations. Aegle marmelos among the lower elevation species and Quercus leucotrichophora among the upper elevation species had the highest wood specific gravity, which were 0.845 ± 0.03 and 0.865 ± 0.02, respectively.  相似文献   
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Background : Potassium (K) availability in soil and plant uptake is restrained by the dynamic interactions among the different pools of K. Aims : To understand these interactions, a study was undertaken to assess the quantity–intensity (Q/I) and buffering characteristics of rainfed maize (Zea mays L.) growing soils. Ten contrasting soils were evaluated for K partitioning changes in exchangeable K (ΔEK) and non‐exchangeable K (ΔNEK) pools in the soil‐solution phase and buffering characteristics using a modified version of Q/I approach. Results : The partitioned Q/I isotherms showed strong adsorption with the increase in K concentration ratio (CRK) and the changes due to ΔEK were higher than changes due to ΔNEK. Total buffering capacity (PBCK) significantly correlated (r = 0.92, p <0.01) with clay content with a major share contributed by buffering capacity owing to non‐exchangeable K ( PBC Δ NEK K ) rather than exchangeable K ( PBC Δ EK K ). The fixation capacity (β) factor, the magnitude of added K converted into a non‐exchangeable pool, ranged from 41 to 63%, whereas release (α) factor, the magnitude of added K converted to the exchangeable pool, ranged from 19 to 36%. Both threshold solution K (CKr) and threshold exchangeable K (EKr) values were found to be high in Satran clay loam (S2) and lower in Doon silty clay loam (S3) soils. The equilibrium exchangeable K (EKo) was found close to minimum exchangeable K (Emin) in Doon silty clay loam (S3) and Babaweyl sandy clay loam (S1) soils and overall Emin constituted about 8.94 to 0.57% of the EKo. Conclusion : It may be concluded that K Q/I isotherm partitioning provides a valuable insight to assess the dynamic relations. The ratio of α/β (K recharge index) could be used to evaluate the K enrichment capacity of soil to K additions while EKr and Emin can be potentially useful in the elucidation of exchangeable K as K fertility index especially in soils with poor K fertilizer management.  相似文献   
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The study was specifically aimed to obtain concentration of beryllium in various environmental matrices such as air, water and soil in the vicinity of the Beryllium Metal Plant situated at Turbhe, New Bombay. Two analytical techniques – Morin fluorescence method and Atomic Absorption Spectrophotometry using graphite furnace were standardised for beryllium estimation. The beryllium concentration in the natural matrices studied – air, water and soil were in the range of 0.41–0.43 ng m-3, 0.01–0.02 ng mL-1 and 325–767 ng g-1 respectively.  相似文献   
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The physicochemical and functional properties of ultraviolet (UV)-treated egg white protein (EW) and sodium caseinate (SC) were investigated. UV irradiation of the proteins was carried out for 30, 60, 90, and 120 min. However, the SC samples were subjected to extended UV irradiation for 4 and 6 h as no difference was found on the initial UV exposure time. Formol titration, SDS-PAGE, and FTIR analyses indicated that UV irradiation could induce cross-linking on proteins and led to improved emulsifying and foaming properties (P < 0.05). These results indicated that the UV-irradiated EW and SC could be used as novel emulsifier and foaming agents in broad food systems for stabilizing and foaming purposes.  相似文献   
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Alterations in the serum lactate dehydrogenase activity of Dictyocaulus filaria infected lambs were studied. The significant increase in its activity during patency correlated well with the progress of the disease and lung damage caused by the parasite. The enzyme may be of use in assessing the potency of D filaria vaccine and the chemotherapeutic value of an anthelmintic. Its use as a non-invasive method for earlier diagnosis and prognosis of the disease under experimental conditions is suggested.  相似文献   
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In major cities, air quality is of significant concern because of its negative effect on the health of the region’s living conditions, climate, and economy. Recent studies show the significance of the data on microlevel pollution which includes severe air pollutants and their impacts on human. Conventional methods of measuring air quality need skilled personnel for accurate data measurement that are based on stationary and limited measuring station networks. However, it is costly to seize the spatio-temporal variability and to recognize pollution hotspots that are necessary to develop real-time exposure control strategies. Due to the restricted accessibility of information and the non-scalability of standard techniques for air pollution monitoring, a real-time system with both higher spatial and temporal resolution is crucial. In recent times, unmanned aerial vehicles (UAVs) mounted with various sensors have been implemented for on-site air quality surveillance as they can offer new methods and research possibilities in air pollution and emission tracking, as well as in the study of environmental developments. An extensive literature review has been conducted, and it was observed that there are types of UAVs and types of sensors that are used for air quality monitoring for the parameters like CO, SO2, NO2, O3, PM2.5, PM1.0, and black carbon. Low-cost wireless sensors have been using for monitoring purpose in the past studies, and when results obtained are validated with the stationary monitoring instruments, the coefficient of correlation (R2) is found to be varied from 0.3 to 0.9. The difficulties, however, are not just technical, but at present time, policies and laws, which vary from country to country, symbolize the major challenge to the extensive use of UAVs in air quality/monitoring studies.

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