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161.
A new ursane was isolated from the leaves of Lantana camara and its structure elucidated as 3,24-dioxo-urs-12-en-28-oic acid (1) by means of spectral analysis. 相似文献
162.
163.
J. C. Dagar O. S. Tomar Y. Kumar R. K. Yadav 《Land Degradation \u0026amp; Development》2004,15(2):143-151
Alkali lands in India occupy about 3 million ha. Due to poor physical properties, excessive exchangeable sodium and high pH, most of these lands support a very poor vegetation cover. Many of the medicinal and aromatic plants are in great demand for both internal requirements and export. But since these crops are non‐conventional in nature, it is not always possible for them to be produced on fertile lands, which can be used for arable crops. The marginal lands, specifically the lands affected by salinity or sodicity problems where profitable returns are not possible from agricultural crops, could be successfully utilized for the cultivation of these high‐value crops with marginal inputs. Results reported in this paper clearly indicated that out of three aromatic grasses, palmarosa (Cymbopogon martinii (Roxb.) Wats.) and lemon grass (C. flexuosus (Steud.) Wats.) could successfully be grown on moderatly alkali soils of pH up to 9·2 while vetiver (Vetiveria zizanioides (L.) Nash), which withstands both high pH and stagnation of water, could successfully be grown without significant yield reduction on highly alkali soils. These grasses not only produce essential oils used for industrial purposes but also ameliorate the soil. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
164.
165.
Santosh Kumar Yadav Sibdas Singha Mahapatra Jae Whan Cho Hoon Cheol Park Jae Yeol Lee 《Fibers and Polymers》2009,10(6):756-760
Multi-walled carbon nanotubes (MWNTs) nanocomposites with the polymer matrix composed of blends of poly(vinylidene fluoride)
(PVDF) and polyurethane (PU) were prepared via functionalization of 3,4,5-triflouroaniline (TFA) on MWNTs. The MWNTs/polymer
nanocomposites showed a dominantly enhanced elongation due to incorporation of PU molecules in PVDF matrix and the improved
MWNTs dispersion in the polymer matrix resulting from functionalization of MWNTs with TFA. The functionalization of TFA on
MWNTs was confirmed by the measurements of Raman, FT-IR spectra, SEM, and TEM images. In addition, the dielectric constant
of nanocomposites increased with an increase of TFA-functionalized MWNTs in PVDF/PU/MWNTs nanocomposites. The polymer blend
nanocomposites incorporating MWNTs may be available as an alternative potential route for the actuator materials. 相似文献
166.
The problem of gully erosion is very severe in the riparian areas of the alluvial deep soil region in India. Research and development have progressed in response to the change in social needs. The earlier strategy of maintenance of law and order has changed to one of reclamation and restoration of the productive capacity of riparian areas. Watershed management in the ravines has been adopted for development of food security, eco‐restoration and pollution control. Case studies on the watershed management in watersheds projects initiated in the mid‐1980s revealed the scope for bringing increased prosperity through crop diversification and eco‐restoration. In consideration of the erosion process, new concepts of management zones and improved conservation and reclamation practices have been developed. The sociological factors have been rationally analysed, as they applied to watershed management in the ravines. A new paradigm of watershed management by group action is necessary in the future. Since the ways of combating the ravine problem and enhancing the productivity of ravine‐degraded lands were made on rational process‐based approach, there is scope for it to be implemented in other countries with similar land and socio‐economic situations. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
167.
Changes in residue management and incorporation of organic manures may help in carbon sequestration, restoring soil organic carbon (SOC) and sustaining the productivity of land under a cropping system. An experiment of multi-ratooning sugarcane (Saccharum officinarum L.) was initiated in 2003 in Inceptisols of Indian subtropics, to assess the effect of different organic manures and chemical fertilizer, on the crop productivity and soil quality. The annual sugarcane shoot biomass production in organic manure treatments was at par with the chemically fertilized treatment. Gross input of carbon (GIC) by the sugarcane crop was estimated to be 11.7–12.4 t ha−1 y−1 in different organic manure treatments compared to 8.4 and 5.0 t ha−1 y−1 in NPK and control treatments, respectively. The respiratory loss of C (RLC) increased linearly with increasing input of C in soil and it ranged from 3.3 to 4.1 t ha−1 y−1 in different treatments with maximum in FYM and minimum in control treatment. The sugarcane biomass added in the soil humified at a rate constant of 0.38 in sub-tropical conditions and an addition of 3.9 t C ha−1 y−1 is required to maintain SOC in equilibrium. After 5 years of sugarcane cropping (one plant + four ratoons) an increase of 2.3–17.1 t ha−1 in SOC over initial content was recorded with different treatments. Results in coming years from this long-term experiment shall add to the present calculated relationships between carbon addition and storage in sugarcane multi-ratooning crop production system under sub-tropical condition of India. 相似文献
168.
Shashi Kala Yadav Salil Sehgal 《Plant foods for human nutrition (Dordrecht, Netherlands)》1997,50(3):239-247
The present investigation was conducted to study the effect of selected processing and storage methods on the concentration
of ascorbic acid and β-carotene in Bathua and fenugreek, leaves. Methods included storage of leaves with or without polythene
bags for 24 and 48 h in a refrigerator at 5°C; at 30°C in polythene bags; drying (sun and oven); blanching (5, 10, 15 min);
open pan and pressure cooking. Ascorbic acid content of fresh leaves was 220.97 to 377.65 mg and β-carotene content was 19.00
to 24.64 mg/100 g, DW. The percent loss of ascorbic acid ranged from 2.03 to 8.77 and 45.15 to 66.9 while lower losses (0.0
to 1.75 and 1.63 to 2.84) of β-carotene were observed in leaves, stored in, the refrigerator and at 30°C, respectively. A
markedly greater reduction in ascorbic acid and β-carotene was observed in dried, blanched and cooked leaves. The study data
suggest that storage of leaves in refrigeration, drying in oven, blanching for a short time and cooking in a pressure cooker
results in better retention of these two vitamins. 相似文献
169.
Ahlawat SP Sunder J Kundu A Chatterjee RN Rai RB Kumar B Senani S Saha SK Yadav SP 《British poultry science》2004,45(2):194-200
1. The present study was conducted to estimate genetic relatedness among Nicobari fowls (Brown, Black and White) and an exotic bird (White Leghorn) using random amplified polymorphic DNA (RAPD) polymorphism. 2. A total of 25 decamer primers were screened among all the breeds of which 24 primers amplified the genomic DNA, generating 2000 to 200 bp bands. Ten primers generated reproducible and distinct RAPD profiles and were used for further analysis. 3. A total of 94 bands were amplified and 30 polymorphic bands (32%) were produced. The number of polymorphic loci ranged from 1 to 5 with an average of 3.0. 4. Among the native breeds Brown Nicobari showed higher genetic similarity (0.85) than Black Nicobari (0.80) and White Nicobari fowl (0.82). 5. Brown Nicobari showed high genetic similarity with Black Nicobari (0.87 +/- 0.029); least similarity was between White Nicobari and White Leghorn (0.77 +/- 0.028). 6. The RAPD profile of all Nicobari fowls on amplification with the primers PBG5 and PBA12 showed specific bands of molecular size 1050 and 785 bp, respectively. 7. The native breeds showed the least genetic distance with each other while White Leghorn appeared to be most distant from the native breeds. 相似文献
170.