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141.
Chithra Syamala Susan John Kuzhivilayil M. Manikantan Nair J. Sreekumar 《Communications in Soil Science and Plant Analysis》2017,48(6):595-607
In India, cassava cultivation is confined in South India. In Tamil Nadu, tubers are used as raw material for starch and sago industry. About 8–10 large-scale starch factories and 150–200 small-scale starch and sago production units are generating nearly 40–60 tonnes of solid waste (thippi) per annum creating serious environmental pollution. A study undertaken to manage it through composting to a nutrient-rich organic manure revealed thippi as acidic with low major and micronutrient concentration, high water-holding capacity, good porosity, low bulk density, high starch, fiber, low protein, and cyanide. Composting of thippi with different combinations of raw materials, microbial cultures, and earthworms indicated that thippi enriched with gliricida and cassava leaves and composted with earthworm had the highest nutrient concentration with narrow carbon to nitrogen (C:N) ratio. The mean concentrations of N, phosphorus (P), potassium (K) calcium (Ca) and magnesium (Mg), iron (Fe), manganese (Mn), copper (Cu), and zinc (Zn) in thippi compost were 1.32, 3.82, 0.40, 2.18, 0.96, 1.11, 0.08%, 11.23, and 89.93 mg/kg, respectively, which is 3.5, 49,7, 32.5, 8, 185, 100, 2.5, and 12 times than thippi. Thippi compost had low bulk density, starch, without fiber and cyanide but high protein suggesting this protocol as a possible alternative for the management of thippi. 相似文献
142.
Z. Abraham R. Senthilkumar K. Joseph John T. V. R. S. Sharma N. V. Nair M. Unnikrishnan P. M. Kumaran Johnson K. George S. Uma M. Latha S. S. Malik S. K. Mishra D. C. Bhandari S. K. Pareek 《Genetic Resources and Crop Evolution》2008,55(8):1279-1289
The Andaman and Nicobar (A&N) group of islands is immensely rich in plant biodiversity. Andaman’s native tribes are hunter-gatherers,
sustaining on wild or marine food and practically do not have any cultivation. Diversity in cultivated crops is presently
maintained in home gardens by settlers from the mainland and other adjoining countries. The National Bureau of Plant Genetic
Resources (NBPGR) through explorations either alone or in association with CARI or with other ICAR institutes has collected
1234 accessions in 48 exploration and collection missions. Variability was collected in rice, cowpea, black gram, green gram,
okra, Chinese spinach, ash gourd, taro, cucumber, pumpkin, bottle gourd, ridge gourd, bitter gourd, chilli, greater yam and
coconut. Indigenous landraces are absent. The in situ conservation of the wild relatives of crops is well taken care of by a large number of protected forest reserves. 相似文献
143.
Nitrogen release patterns from seven leguminous trees were determined from 8-week laboratory incubations. The quantities
of extractable NH4
+-N and NO3
– released to the soil to which the leaves had been applied was determined at weekly intervals and was related to the initial
N, polyphenol, and lignin concentration of the leaves. Cumulative N mineralized was not correlated to initial N, soluble polyphenol
and insoluble tannin concentrations, but was correlated to lignin and neutral detergent fibre N (NDF-N) concentrations. The
ratios of NDF-N : N (r=0.68 at P<0.05), soluble polyphenol : N (r=0.70 at P<0.05) and (lignin+polyphenol) : N (r=0.75 at P<0.05) were negatively correlated with N release. Total polyphenol content was not a useful predictor of N release, but the
reactivity of the polyphenols as measured by their protein-binding capacity can be a useful predictor. In addition to measuring
the concentration of polyphenols, their reactivity with proteins must be measured, in order to assess their role in regulating
N release. The (lignin+polyphenol) : N ratio could be used to screen leguminous tree leaves for their potential to release
N in short-term experiments. This would allow for rapid screening of a large number of trees without detailed and expensive
field experimentation.
Received: 30 June 1997 相似文献
144.
145.
WM Itano JJ Bollinger JN Tan B Jelenkovic X Huang DJ Wineland 《Science (New York, N.Y.)》1998,279(5351):686-689
Single crystals of a one-component plasma were observed by optical Bragg diffraction. The plasmas contained 10(5) to 10(6) single-positive beryllium-9 ions (9Be+) at particle densities of 10(8) to 10(9) per cubic centimeter. In approximately spherical plasmas, single body-centered cubic (bcc) crystals or, in some cases, two or more bcc crystals having fixed orientations with respect to each other were observed. In some oblate plasmas, a mixture of bcc and face-centered cubic ordering was seen. Knowledge of the properties of one-component plasma crystals is required for models of white dwarfs and neutron stars, which are believed to contain matter in that form. 相似文献
146.
PO Wennberg TF Hanisco L Jaegle DJ Jacob EJ Hintsa EJ Lanzendorf JG Anderson R Gao ER Keim SG Donnelly LAD Negro DW Fahey SA McKeen RJ Salawitch CR Webster RD May RL Herman MH Proffitt JJ Margitan EL Atlas SM Schauffler F Flocke CT McElroy TP Bui 《Science (New York, N.Y.)》1998,279(5347):49-53
The concentrations of the hydrogen radicals OH and HO2 in the middle and upper troposphere were measured simultaneously with those of NO, O3, CO, H2O, CH4, non-methane hydrocarbons, and with the ultraviolet and visible radiation field. The data allow a direct examination of the processes that produce O3 in this region of the atmosphere. Comparison of the measured concentrations of OH and HO2 with calculations based on their production from water vapor, ozone, and methane demonstrate that these sources are insufficient to explain the observed radical concentrations in the upper troposphere. The photolysis of carbonyl and peroxide compounds transported to this region from the lower troposphere may provide the source of HOx required to sustain the measured abundances of these radical species. The mechanism by which NO affects the production of O3 is also illustrated by the measurements. In the upper tropospheric air masses sampled, the production rate for ozone (determined from the measured concentrations of HO2 and NO) is calculated to be about 1 part per billion by volume each day. This production rate is faster than previously thought and implies that anthropogenic activities that add NO to the upper troposphere, such as biomass burning and aviation, will lead to production of more O3 than expected. 相似文献
147.
The atmospheric residence time for methyl bromide (CH3Br) has been estimated as 0.8 +/- 0.1 years from its empirical spatial variability relative to C2H6, C2Cl4, CHCl3, and CH3Cl. This evaluation of the atmospheric residence time, based on Junge's 1963 general proposal, provides an estimate for CH3Br that is independent of source and sink estimates. Methyl bromide from combined natural and anthropogenic sources furnishes about half of the bromine that enters the stratosphere, where it plays an important role in ozone destruction. This residence time is consistent with the 0.7-year value recently calculated for CH3Br from the combined strength estimates for its known significant sinks. 相似文献
148.
N.V. Nair 《Euphytica》1999,108(3):187-191
Four intergeneric hybrids were produced by crossing sorghum [ Sorghum bicolor (L.) Moench, 2n =20] as a female parent with sugarcane ( Saccharum officinarum L., 2n = 112). The hybrids were morphologically similar to the sugarcane parent, but lacked vegetative vigour. Sorghum characters
present in the hybrids included soft texture of the leaves, tight clasping of the leaf sheaths, presence of aerial roots and
triangular ligule. All the hybrids were highly susceptible to natural incidence of mites. Somatic chromosome number of the
hybrids ranged from 2n = 62–66, indicating n+n transmission. This is the first report of Sorghum × Saccharum hybrids with sorghum cytoplasm.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
149.
Comparison of the Johne''s absorbed EIA and the complement-fixation test for the diagnosis of Johne''s disease in cattle 总被引:2,自引:0,他引:2
SE RIDGE IR MORGAN DC SOCKETT† MT COLLINS† RJ CONDRON NW SKILBECK† JJ WEBBER§ 《Australian veterinary journal》1991,68(8):253-257
A commercially available absorbed ELISA for the diagnosis of Johne's disease (JD) (paratuberculosis) in cattle, the Johne's Absorbed EIA, was compared with the conventional complement-fixation test (CFT) used in Australia. Stored plasma from 3 Victorian dairy herds with a history of JD, sera from specimens submitted from animals showing clinical signs of JD and sera from the US National Repository for Paratuberculosis Specimens were used to determine the sensitivity of each test. The EIA detected 48.8% of 43 Australian animals with subclinical JD, while the CFT detected only 12 (21.4%) of 56 subclinically affected cattle. Of 150 subclinically infected US cattle, the EIA detected 47.3% and the CFT detected 52.0%. The EIA detected 59.7% of animals which at the time of sampling were shedding Mycobacterium paratuberculosis in their faeces, but showed no clinical signs of JD, while the CFT detected 57.3%. The EIA correctly identified 88.2% of 136 histologically confirmed clinical cases, and the CFT detected 83.4%. The specificity of each test was determined by testing sera collected at slaughter from animals residing in a known JD-free area of Australia, and from samples from the US National Repository of Paratuberculosis Specimens collected from certified-free herds in Wisconsin. The EIA was found to have a specificity of 99.8% when 998 Australian animals were used as the test population, and 99.0% when 196 US animals were used. The specificity of the CFT using Australian samples was 96.9% and 95.2% using American samples. 相似文献
150.
Bacteroides nodosus involved in several outbreaks of ovine footrot over a number of years were subjected to DNA restriction endonuclease analysis. Individual isolates were found to have characteristic Bam HI profiles which permitted their accurate identification and differentiation from other isolates. Bam HI profiles of B. nodosus isolates were used in epidemiological investigations involving consecutive outbreaks of footrot on individual and neighbouring farms. The relationship of given isolates to a common source could be established by this means. Restriction endonuclease analysis provides an additional epidemiological tool in ovine footrot investigations as it accurately identifies interstrain differences in a manner not possible by conventional bacteriological and serological means. 相似文献