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991.
Wheat class identification using monochrome images 总被引:2,自引:0,他引:2
Wheat class identification by bulk sample analysis using a machine vision method would be helpful for automation of grain handling, binning and shipping operations in grain elevators. A machine vision system with a monochrome camera was used to identify eight western Canadian wheat classes at four moisture levels (11%, 14%, 17% and 20% wet basis) by bulk sample analysis (n=100 images for each group of samples). Grayscale images (1024×768 pixels) of the grain bulk were captured by the monochrome camera, and stored on a data acquisition system. Algorithms were developed to extract 32 textural features automatically from the grayscale images. The mean gray values of the western Canadian wheat classes ranged between 106 and 143, and it was the highest for Canada Prairie Spring Red and the lowest for Canada Western Extra Strong and Canada Western Red Winter. The mean gray values of the wheat samples were significantly higher at 17% moisture content and lower at 11% moisture content among the tested moisture levels (α=0.05). The overall classification accuracies of a quadratic discriminant function were 93.8%, 92.5%, 92.0% and 94.4% when the wheat classes were at 11%, 14%, 17% and 20% moisture contents, respectively. Similarly, the accuracies of a linear discriminant function were 96.1%, 95.0%, 95.4% and 96.3% at 11%, 14%, 17% and 20% moisture contents, respectively. When the wheat classes were identified irrespective of moisture levels (images of the four moisture level grains in each class were mixed together), the accuracy was 89.8% and 85.4% for quadratic and linear discriminant functions, respectively. A monochrome image analysis system has the potential to use for online identification of classes in wheat handling facilities. However, further research is required to determine the performance of the developed method for impurities in bulk grain such as foreign material and dockage. 相似文献
992.
Increased flour yield in hard wheat is associated with increased endosperm rheology index, calculated from strength and stiffness as measured by the SKCS. A study of the fractured endosperm of hard wheat varieties grouped according to similar rheology index values was performed using environmental scanning electron microscopy (ESEM). Differing microstructures and fracture patterns were observed between each group. Specifically, the group representing high rheology index had a greater concentration of small starch granules in prismatic cells. Samples of diverse wheat germplasm were grown at two sites and subjected to laboratory milling. Starch granule size distribution (SGSD) analysis using a laser diffraction method was undertaken on a subset of samples in triplicate representing a range in flour yield. The results supported an hypothesis for a significant influence of SGSD on flour yield of hard wheat varieties. In addition, a significant part (R2>0.40 (p<0.05) at two sites) of the association appeared to be under genetic control. Results indicate a more even gradation of distributions involving an increase in the sample volume % of small granule (types B and C) and decrease in type A granules. This was associated with increased rheology index values and higher flour yield. The ratio of type A:C starch granules accounted for up to 58% (p<0.05) of the variation in flour yield in the samples studied. Thus, rheological parameters measured using a rapid SKCS screening method can be linked to the genetic regulation of SGSD with implications for the improvement of commercial processing performance of hard wheat. 相似文献
993.
Foliar and tuber blight caused by Phytophthora infestans accounts for significant losses in potatoes in field and storage. Nevertheless, limited research has been published on the
effects of cultural practices on late blight control. Field experiments were conducted in two years on Howard gravely loam
soil in New York State to evaluate the effectiveness of mulching using oat straw and hilling in preventing tuber blight infection
for cvs Allegany and Katahdin. Potato hilling and mulching had little effect on foliar blight development. The cultivar affected
the disease development in the foliage, with cv. Allegany showing lower foliar late blight than cv. Katahdin. Tuber blight
incidence averaged 25% for cv. Allegany and 3% for cv. Katahdin in hilled plots, while in the mulched plots the incidence
of tuber blight averaged 33% for cv. Allegany and 10% for cv. Katahdin. The straw hay mulch was ineffective in tuber blight
control. Tubers set at a soil depth of more than 7 cm had lower tuber blight incidence than shallow tubers set at a depth
of less than 7 cm. In both years, hilling provided partial protection of tubers but its effectiveness was limited in the presence
of favourable conditions for late blight development. Even though large hills had proportionally a lower tuber blight incidence
than medium-sized hills, the difference between the different hill sizes was not significant. These studies suggest that the
use of cultivars with foliage resistance to late blight in combination with cultural practices may partially reduce the incidence
of tuber blight.
Mention of trade names or commercial products in this publication is solely for the purpose of providing specific information
and does not imply recommendation for endorsement by Cornell University or the US Department of Agriculture. 相似文献
994.
Porcu OM Rodriguez-Amaya DB 《Plant foods for human nutrition (Dordrecht, Netherlands)》2008,63(4):195-199
The indigenous pitanga (Eugenia uniflora L.) is now marketed and commercially processed in Brazil. In the present work, the carotenoids of the pitanga fruit from two states and at two stages of ripening, as well as of processed pitanga products (frozen pulp and juice, the brands being designated as A, B and C) commercialized in Campinas, São Paulo, were determined by HPLC. As compared to ripe pitanga from Medianeira, Paraná, those from Campinas had significantly higher (all-E)-lycopene (14.0 vs. 71.1 μg/g), (13Z)-lycopene (1.1 vs. 5.0 μg/g) and (all-E)-γ-carotene (1.6 vs. 3.8 μg/g) levels. Significant increases in most of the carotenoids occurred from the partially ripe to the ripe fruits, with (all-E)-lycopene doubling its concentration in fruits from both states. Pitanga was found to be one of the richest fruit sources of carotenoids, particularly lycopene, but the processed products had much lower lycopene content. The mean (all-E)-lycopene concentration was 16.6 μg/g for frozen pulp brand A, 23.0 μg/g for bottled juice brand B and 25.6 μg/g for bottled juice brand C. Optimization of processing is therefore needed to guarantee better retention of this important carotenoid. 相似文献
995.
A series of shape memory polyurethane (PU) copolymers synthesized from 1,4-phenyldiisocyanate (PDI), poly(tetramethyleneglycol)
(PTMG), 1,4-butanediol (BD) as a chain extender, and glycerol as a cross-linking agent were tested for the mechanical properties
and the shape memory effect at the temperature 20 °C above melting temperature (T
m), and were compared with other PUs synthesized from 4,4′-methylene-bis-phenyldiisocyanate (MDI), PTMG, and BD. Mechanical
properties and shape memory effect were improved substantially by adopting both PDI and glycerol. Interestingly, enthalpy
of melting and T
m were not affected by the glycerol content. Vibration and shock absorption ability was investigated by measuring both loss
tan δ and storage modulus with dynamic mechanical analyzer (DMA). 相似文献
996.
Previously, we have reported a method for producing photochromic wool fabric by applying a thin layer of hybrid silica-photochromic
dye onto the wool surface. While the photochromic coating showed a very fast optical response and had little influence on
the fabric handle, its durability was poor. In this study, the durability of the photochromic coating layer was improved by
introducing epoxy groups into the silica matrix via co-hydrolysis and co-condensation of an alkyl trialkoxysilane compound
(ATAS) and 3-glycidoxypropyltrimethoxysilane (GPTMS). The presence of epoxy groups in the silica enhanced both washing and
abrasion durability or fastness. In addition, the optical response speed was slightly increased as well. Effects of the type
of alkyl silane and the GPTMS/alkyl silane ratio on the coating durability, fabric handle and optical response were examined. 相似文献
997.
Summary Flowering and true seed production from different order inflorescences in potato (Solanum tuberosum L.) were evaluated in two experiments. The number of flowers per inflorescence, berry set, berry weight, number of seeds
per berry and seed weight generally decreased from primary inflorescences to tertiary inflorescences and inflorescences on
lateral stems. The possible relation with carbohydrate distribution is discussed. Quality of the seeds produced from the different
orders of inflorescences was a function of seed size; larger seeds showed better germination, emergence and seedling growth.
Late harvest of berries increased berry weight and number of seeds per berry from primary inflorescences. Application of additional
nitrogen during the flowering period did not affect flowering or differences between inflorescence positions in seed production,
but it significantly decreased the number of seeds per berry. The practical implications of these results for true seed production
are discussed. 相似文献
998.
Enzyme-linked immunosorbent assay (ELISA), with single or combined antisera was effective for diagnosing potato virus S (PVS), potato virus X (PVX) or both viruses in plants grown in the greenhouse or field. In dormant tubers, stolon, middle and apical end composite sampling with or without eyes and sprouted tubers produced reliable positive assays for PVX. Only tuber pieces with sprouts resulted in consistently reliable assays for PVS. Composite sampling of potato foliage was effective for detecting one PVX infected plant in a total of 100 Kennebec, Norland, or Russet Burbank plants. There were some false negative results and greater variability in composite PVS assays, but on average, one PVS infected plant can be detected in composites of 10 Kennebec, Norland, or Russet Burbank plants. Sodium diethyldithiocarbamate (0.01M NaDIECA) in phosphate buffered saline + 0.5% Tween (PBS-T) added to plant extracts enhanced specific reactions for either virus. Onceor twiceused enzyme conjugate was effective in ELISA of either virus from potato foliage. 相似文献
999.
M. G. Moraes N. J. Chatterton P. A. Harrison T. S. Filgueiras R. C. L. Figueiredo‐Ribeiro 《Grass and Forage Science》2013,68(1):165-177
Non‐structural carbohydrates (NSC) are the primary energy available for growth and dry‐mass production in forage grasses. They are also associated with tolerance to environmental stresses, including drought. Soluble carbohydrates, especially fructans of temperate forage grasses, have been extensively studied; however, little is known about NSC of tropical grasses. These plants are abundant in the Cerrado, a savanna‐like vegetation with a definite seasonality in rainfall distribution. Such an environment presents an ideal condition for the occurrence of fructans. However, the present analysis of carbohydrates in aerial parts of twenty‐four tropical grass species, mainly from the Panicoideae subfamily in the Cerrado, shows a distinctively different NSC profile when compared with temperate grasses. Free glucose and starch are common NSC found in most plant organs. However, free fructose and sucrose‐based oligosaccharides were only found in very low amounts. Sucrose was detected in higher amounts only in stems. A linear series of malto‐oligosaccharides was found in leaf blades, sheaths and stems of most of the Cerrado grasses, except for those from the Andropogoneae tribe. These results indicate a diversity of regulatory pathways of NSC metabolism in tropical forage grasses from the Cerrado. 相似文献
1000.
Roop Kishore Ashish Dwivedi Raghuvir Singh R. K. Naresh Vineet Kumar Priyanka Bankoti Dinesh Kumar Sharma Nishant Yadav 《Paddy and Water Environment》2017,15(1):49-58
Weeds caused serious problem on yield reduction of basmati rice worldwide. Losses caused by weeds varied from one country to another, depending on the presence of dominant weeds and the control methods practiced by farmers; therefore, suitable plant population and weed management practices should be adopted. Keeping these in mind, a field experiment was carried out during kharif seasons of 2009 and 2010 at crop Research Centre of SVPUA&T, Meerut, India comprising 4 planting geometries, viz. 20, 30, 40, and 50 hills m?2 as main plot factor, and 5 weed management practices (Butachlor @ 1.0 kg ha?1, Butachlor @ 1.0 kg ha?1 fb (followed by) one hand weeding, Butachlor @ 1.0 kg ha?1 fb Almix @ 4 g ha?1, two hand weedings and weedy check) in a split plot design with 3 replications. Experimental results revealed that plant population of 50 hills m?2 proved superior over that of 20 hills m?2 in respect of weed density, weed dry weight, number of tillers m?2, yield attributes, grain, straw, and biological yields. The maximum grain yield (29.00 and 31.00 q ha?1) and straw yield (51.30 and 52.50 q ha?1) were recorded in 50 hills m?2 followed by 40 hills m?2 during 2009 and 2010, respectively. In respect of nitrogen, phosphorus, and potassium removal, a reverse trend was observed: the highest in 20 hills m?2 followed by 30, 40, and 50 hills m?2. As far as the weed management practices are concerned, both chemical and mechanical methods of weed control were found superior over weedy check. The lowest weed density, dry weight, and highest weed control efficiency, maximum length of panicle?1, number of panicle (m2), and 1000-grain weight and grain yield of 30.40 and 32.60 q ha?1 were recorded with two hand weedings which was at par with Butachlor @ 1.0 kg ha?1 fb one hand weeding over rest of the weed management practices. 相似文献