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81.
In this study, Berberis vulgaris L. wood as an agricultural waste was used for dyeing and functional finishing of cotton. To facilitate the attachment of natural dye, citric acid was used to create carboxylic acid functional groups on cotton fibers. The process of crosslinking of cotton fabric with citric acid was optimized in order to obtain the maximum dyeability with the cationic natural dye. The effects of three important factors including citric acid concentration, sodium hypophosphite concentration and curing temperature on the color strength of the dyed samples with woods of barberry tree were analyzed by response surface methodology and the optimum conditions for obtaining the highest color strength was obtained. The crosslinking of citric acid on cotton fibers was confirmed by FTIR spectroscopy. The dyed sample prepared under the optimum conditions of crosslinking showed good wash and light fastness properties besides very good antibacterial activity against gram-negative and gram-positive bacteria.  相似文献   
82.
This study attempts to evaluate the nutrient element and carbohydrate distribution within Water-Stable Aggregates (WSA) of two natural ecosystems, native forest and pasturelands, under different land uses. Soil samples were collected from depths of (0-20) cm in Typic Haploxeroll soils. The overall pattern indicated that Mean Weight Diameter (MWD) and WSA were greater in the pasture and forest soils compared with the adjacent cultivated soils and aggregates of > 1.0 mm size were dominant in the uncultivated soils, whereas the cultivated soils comprised aggregates of the size < or = 0.5 mm. Distribution of organic carbon, nitrogen, phosphorus and carbohydrates within the WSA showed preferential enrichment of these parameters in the macroaggregate fraction (4.75-1.0 mm) for the uncultivated soils and microaggregate fraction (> 0.25 mm) for the cultivated soils. Average distribution of total exchangeable bases within WSA showed that cultivation of forest pastureland soils significantly led to reduce in these nutrient in the 4.75-2.0 mm fraction and increase in concentration of these cations in < 0.25 mm fraction. Since smaller aggregates are preferentially removed by erosion, this study emphasizes the need for sustainable soil management practices that they will minimize nutrient loss when forest or pastures lands are converted to cropland.  相似文献   
83.
84.
Society in Bangladesh has specific gender roles with strong values and norms in which women are controlled and protected by men. Certain deviations degrade the women socially and trap them into prostitution. This paper investigates the situation of prostitutes in Bangladesh through analysis of the environment at their place of origin that instigated them into the present situation. The paper describes the present environment of the prostitutes in Narayanganj, identifies their spatial connectivity through determining their activity space and sphere of influence and makes some brief remarks about the old age situation of these prostitutes.  相似文献   
85.
This study examined the effect of site and elevation on the oven-dry density and volumetric shrinkage of hornbeam (Carpinus betulus) wood.For this purpose,45 normal hornbeam trees from three different sites (Mazandaran,Guilan and Golestan) at three elevations,300 m (low elevation),700 m (intermediate elevation) and 1100 m (high elevation) from natural forest in northern Iran were selected.Disks were cut at breast height from mature wood and test samples were prepared to determine physical properties,i.e.,wood density and volumetric shrinkage.The results show that there are significant differences between site and elevation on these physical properties of wood.The interaction effects between site × elevation on wood density and volumetric shrinkage were also statistically significant.At any fixed site,wood density and volumetric shrinkage increased with elevation.As well,their values at Guilan were higher than those at the other two sites.The relationship between wood density and volumetric shrinkage was determined by simple regression equations.Strong,positive relationships between wood density and volumetric shrinkage at each site were found.Again,these were stronger at the Guilan site than at the other two sites.Given a fixed site,the correlation at high elevation was stronger than at the other two elevations.  相似文献   
86.
Majid Azizi 《林业研究》2008,19(4):323-328
The objective of this research is to design a method for an appropriate alternative to supply poplar wood as raw material for wood and paper factories in Iran.Due to the destruction of the forests and lack of proper plantation,replacement of the forest wood by the fast growing wood is vital to satisfy all requirements of these factories.A hierarchy was used to prioritize benefits,opportunities,costs and risks (BOCR) using the Analytic Hierarchy Process (AHP) ratings approach.To evaluate the "control criteria" of the system,a control hierarchy was also created and prioritized by applying the Analytic Network Process (ANP).A total of four major control criteria in the system are prioritized where each one controls a network structure evaluated by using ANP.The final synthesis results of the system showed that internal poplar tree farming supplied by the forest product factories was the best choice among three potential alternatives (factory procurement,external procurement and mix procurement).  相似文献   
87.
The rehabilitation or intensified use of Imperata grasslands will require a much better understanding of their area, distribution, and characteristics. We generated estimates of the area of Imperata grasslands in tropical Asia, and suggested a typology of Imperata grasslands that may be useful to define the pathways toward appropriate land use intensification. We conclude that the area of Imperata grasslands in Asia is about 35 million ha. This about 4% of the total land area. The countries with the largest area of Imperata grasslands are Indonesia (8.5 million ha) and India (8.0 million ha). Those with the largest proportion of their surface area covered with Imperata are Sri Lanka (23%), the Philippines (17%), and Vietnam (9%). Laos, Thailand, Myanmar, and Bangladesh evidently all have similar proportions of their land area infested with Imperata (about 3 to 4%). Malaysia (< 1%), Cambodia (1%), and the southern part of China (2%) have but a minor proportion of their total land area in Imperata. The species was found widely distributed on the full range of soil orders. It occupied both fertile (e.g. some of the Inceptisols and Andisols) and infertile soils (Ultisols and Oxisols) across a wide range of climates and elevations. Imperata lands fall into four mapping scale-related categories: Mega-grasslands, itmacro-grasslands, meso-grasslands, and micro-grasslands. The mega-grasslands are often referred to as sheet Imperata. They are the large contiguous areas of Imperata that would appear on small-scale maps of say 1:1,000,000. We propose that this basic typology be supplemented with a number of additional components that have a key influence on intensification pathways: land quality, market access, and the source of power for tillage. The typology was applied in a case study of Indonesian villages in the vicinity of Imperata grasslands. We propose an international initiative to map and derive a more complete and uniform picture of the area of the Imperata grasslands. This should include selected studies to understand conditions at the local level. These are critical to build the appreciation of change agents for the indigenous systems of resource exploitation, and how they relate to local needs, values and constraints.  相似文献   
88.
We measured erodibility and mean weight diameter (MWD) of soil aggregates in different parts of a forest road. Samples of topsoil were collected from cutslope, fillslope, road surface and forest ground to assess the texture, bulk density, moisture, CaCO3 and organic matter. Soil aggregate stability was determined by wet sieving. Soil erodibility on the road surface was 2.3 and 1.3 times higher than on the fillslope and cutslope, respectively. The forest soil had the lowest erodibility. Aggregate stability of cutslope and road surface were low and very low, respectively. There was a significant negative relationship between cutslope erodibility with CaCO3 and sand content. Cutslope erodibility increased with increasing silt, clay and moisture content. On fillslopes, MWD increased with in-creasing rock fragment cover, plant cover, litter cover, organic matter and sand. There was a strong negative correlation between fillslope erodibility and organic matter, sand and MWD. There was no significant difference between erodibility of bare soil and soils beneathRubus hyrcanusL. and Philonotis marchica (Hedw.) Brid.  相似文献   
89.
Laboratory studies were conducted to determine the effects of Trioxys angelicae Haliday (Hym.: Braconidae) age and host density (Aphis fabae Scopoli) (Hem.: Aphididae) on selected attributes of parasitoid reproductive biology. The number of hosts parasitized per day was used as an estimate of wasp fecundity. Parasitoid longevity was not affected by host density and at host densities of 2, 4, 6, 8, 10, 15, 20, 30, 40 or 60 aphids per day; the parasitoids lived an average of 8.96 ± 0.82 days at 21°C. At host densities of ≤20 aphids per day, lifetime fecundity of a single Trioxys angelicae female was limited by the number of hosts available. Lifetime fecundity was highest with an average of 158.14 ± 20.33 at a density of 30 aphids per day; the maximum number of aphids parasitized by any female was 235. Daily fecundity and sex ratio were affected by parasitoid age and host density. Age-specific fecundity at different host densities fitted well to a nonlinear model. In conclusion, the fecundity and female progeny production of Trioxys angelicae as an important biological control agent of A. fabae is influenced by host availability.  相似文献   
90.
To avoid environmental pollution due to excessive use of inorganic fertilizers, it is essential to increase the availability of nutrients using environmentally friendly resources, such as composts and clinoptilolite zeolite, in soil fertility management. In this study, an attempt was made to use different rates of inorganic fertilizers, compost, and clinoptilolite zeolite to correct the ongoing excessive use of inorganic fertilizers. A pot study using maize (Zea mays L.) as a test crop was carried out to determine the effects of amending inorganic fertilizers with compost and clinoptilolite zeolite on: (i) selected soil chemical properties, and (ii) N, P, and K uptake and use efficiency in maize cultivation. The pot study was conducted for 45 days (tasseling stage of maize). Amending inorganic fertilizers with compost and clinoptilolite zeolite increased soil total N, exchangeable Ca, Mg, K, and available P. Furthermore, P and K uptake and use efficiency of maize were significantly improved upon amending inorganic fertilizers with compost and clinoptilolite zeolite. Soil chemical properties and productivity of maize on acid soils can be improved through co-application of compost and clinoptilolite zeolite. However, field application of the authors’ findings is being evaluated in an on-going field experiment.  相似文献   
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