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981.
Palanisamy Muthukumar Hak-Soo Kim Kyo-Sun Ku Jong Ho Park Young-A. Son 《Fibers and Polymers》2016,17(4):553-559
The synthesis of two new phthalocyanine precursors 4-(3-(piperidin-1-yl)phenoxy) with mono (2) and trichloro (3) substituents were carried out in this work. Cyclotetramerization of these precursors with zinc acetate gave novel tetrakis-4-(3-(piperidin-1-yl)phenoxy) with tetra (4) and dodecachloro (5) substituted zinc phthalocyanines. The synthesized new compounds were characterized using FT-IR, 1H NMR, electronic absorption spectroscopy, mass spectra and elemental analysis. The aggregation behavior of zinc phthalocyanines 4 and 5 was investigated in different concentrations of dichloromethane (DCM). Zinc phthalocyanines 4 and 5 showed good solubility in different organic solvents such as DCM, CHCl3, THF, benzene and toluene. Further, the aggregation behavior of zinc phthalocyanines 4 and 5 was studied before and after the addition of Triton X100. Further, the fluorescence quantum yields of zinc phthalocyanines 4 and 5 were calculated in the presence and absence of Triton X100. 相似文献
982.
Kim Sam Soo Leem Su Gyung Ghim Han Do Kim Joon Ho Lyoo Won Seok 《Fibers and Polymers》2003,4(4):204-209
The effect of padding solution on the microwave heat dyeing of polyester fabric was studied extensively. Polyester fabrics
were impregnated in aqueous urea solution and aqueous sodium chloride solution for 10 min and then dyed for 7 min by microwave
apparatus (2 450 MHz, 700 W) under optimum conditions which provide good exhaustion. Aqueous solutions of urea and sodium
chloride showed more effective than water as a padding solution for microwave heat dyeing. The type of solvent added in padding
media and its concentration significantly affects the K/S values of dyed polyester fabric. Added solvents such as n-hexane,
acetone, and dimethyl formamide were also more effective than 100% water as padding media for the microwave heat dyeing. It
is supposed that the effect of used solvents on dyeing property of polyester fabrics depends on the solubility parameter difference
between solvent and polyester fabric. 相似文献
983.
Additives, such as sodium perborate and borax, were examined in dialdehyde wrinkle resistant finishing of cotton. Results
indicated that the whiteness index (WI) of cotton treated with dialdehyde and additive showed about 90% of WI of the untreated
cotton but with decrease in wrinkle recovery angle (WRA) due to inhibition effect of these additives. Effect of additive on
the WRA reduction was more prominent with glutaraldehyde than with glyoxal. Reduction in WRA of cotton treated with both dialdehydes
and boron compound was minimized by simultaneous addition of formic acid in the bath. Addition of formic acid was also generally
beneficial in maintaining WI retentions after 8 months storage. Furthermore, boron compounds were also effective in improving
retentions of mechanical properties. By FTIR analysis the residual aldehyde group was detected on the dialdehyde-finished
cotton, whereas no peak was shown by addition of boron compounds. This suggested that the residual aldehyde group was a main
cause of fabric yellowing on the dialdehyde-finished cotton. Dialdehyde with boron compound, therefore, can be used to replace
a conventional formaldehyde-containing wrinkle resistant finishing of cotton. 相似文献
984.
Mikyung Kim Seokhan Yoon Taekyeong Kim Jin-seok Bae Namsik Yoon 《Fibers and Polymers》2006,7(4):352-357
The cotton fabrics were pretreated by sodium 2-(2,3-dibromopropionylamino)-5-(4,6-dichloro-1,3,5-triazinylamino)-benzenesulfonate
(DBDCBS) at alkaline condition of room temperature and then dyed with four disperse dyes having amino groups (C.I. Disperse Yellow
9, C.I. Disperse Red 11, C.I. Disperse Blue 56 and C.I. Disperse Violet 1) at acidic condition of high temperature. A novel
hetero-bifunctional bridge compound,DBDCBS, has two reactive groups such as dichloro-s-triazinyl group andα, β-dibromopropionylamido group. The first has reactivity towards hydroxy group of cellulosic fiber and the second shows reactivity
towards amino groups of disperse dye containing amino groups. The results indicate that it is possible to dye polyester/cotton
blend at one-bath dyeing using one kind of disperse dye containing amino groups. Therefore, two kinds of dyeing methods such
as two-bath process one-bath dyeing and one-bath process one-bath dyeing were investigated and their dyeabilities were compared.
The differences between these two methods were negligibly small so that perfect one-bath one-step dyeing of polyester/cotton
blend by one kind of disperse dye was achieved. 相似文献
985.
Liquid crystalline spiroxazine derivatives have been synthesized. The spiroxazines obtained were characterized by1H-NMR, IR spectroscopy, UV and GC-MS. 相似文献
986.
The sprout inhibitor chlorpropham (CIPC) was applied in varying concentrations to individual eyes of potato tubers. Sensitivity of a given eye to CIPC depended upon the status of the remaining eyes on the same tuber. If the remaining eyes were inhibited, higher concentrations of CIPC were required for inhibition of the given eye. Apical eyes were more sensitive to CIPC than were lateral eyes. It was confirmed that CIPC is highly volatile and that contaminating levels of CIPC vapors can induce a rosette sprout growth. Seed potatoes treated with low concentrations of CIPC before planting sprouted more slowly than untreated potatoes, and the delay was related to CIPC concentration. At high CIPC levels, total emergence as well as rate of emergence was reduced. However, emergence was far greater than would have been anticipated from the sprouting of similar treated lots held in storage. 相似文献
987.
The effect of main chain structure of anion-containing copolyesters on the properties of copolyester sizing agents was investigated.
The copolyesters were prepared by conventional two step polymerization technique from DMT, DMI, DMS, EG, and DEG. The copolyesters
synthesized were characterized by atomic absorption spectroscopy,1H-NMR Spectroscopy, GC, FTIR Spectroscopy, and DSC. The solubility decreased as the DMT content increased. The copolyesters
having DMT:DMI=1:1 showed the minimum viscosity. The effect of EG content on the solution stability was not clear and the
samples having high DMI content showed better solution stability. The water resistance was best when only DMI and EG were
used, while it was worst when DMT:DMI was 1:0. 相似文献
988.
Haruto Sasaki Takahiro Hara Satoshi Ito Naoko Uehara Han-Yong Kim Mark Lieffering Masumi Okada Kazuhiko Kobayashi 《Field Crops Research》2007
Increasing global atmospheric CO2 concentrations are expected to influence crop production. To investigate the effect on rice (Oryza sativa L.), plants were grown under ambient CO2 (AMB) or free-air CO2-enrichment (FACE) at CO2 concentrations ranged from 275 to 365 μmol mol−1 above AMB. We supplied 13CO2 to the plants at different growth stages so we could examine the contribution of carbohydrate stored during the vegetative stage or newly fixed carbohydrate produced during the grain-filling stage to ear weight at grain maturity. In plants supplied with 13C at the panicle-initiation or pre-heading stages, plants grown under FACE had more starch in the stems at heading, but there was no difference in stem 13C content. Furthermore, there were no differences between treatments in whole-plant 13C contents at heading and grain maturity. In contrast, plants supplied with 13C at the grain-filling stage had more 13C in the whole plant and the ears at grain maturity under FACE than under AMB, indicating that the increased amount of photosynthate produced at the grain-filling stage under CO2 enrichment might be effectively stored in the grains. Furthermore, regardless of when the 13C was supplied, plants had more 13C in starch in the ears at grain maturity under FACE than under AMB. Therefore, CO2 enrichment appears to promote partitioning of photosynthate produced during both vegetative and grain-filling stages to the grains. 相似文献
989.
Jung-Eun Yang Young-Hee Lee Young-Seok Koo Young-Jin Jung Han-Do Kim 《Fibers and Polymers》2002,3(3):97-102
A series of waterborne poly(urethane-urea) anionomers were prepared from isophorone diisocyanate (IPDI), polycaprolactone
diol (PCL), dimethylol propionic acid (DMPA), ethylene diamine (EDA), and triethylamine (TEA), NaOH, or Cu(COOCH3)2 as neutralizing agent. This study was performed to decide the effect of neutralizing agent type on the particle size, viscosity,
hydrogen bonding index, adhesive strength, antistaticity, antibacterial and mechanical properties. The particle size of the
dispersions decreased in the following order: TEA based samples (T-sample), NaOH based samples(N-sample), and Cu(COOCH3)2 based sample (C-sample). The viscosity of the dispersions increased in the order of C-sample, N-sample, and T-sample. Metal
salt based film samples (N and C-sample) had much higher antistaticity than TEA based sample. By infrared spectroscopy, it
was found that the hydrogen bonding index (or fraction) of samples decreased in the order of T-sample, N-sample, and C-sample.
The adhesive strength and tensile modulus/strength decreased in the order of T-sample, N-sample, and C-sample. The C-sample
had strong antibacterial halo, however, T- and N-samples did not. 相似文献
990.
Isolation,partial purification and characterization of a potato peel ∞-solanine cleaving glycosidase
An enzyme which hydrolyzes the rhamnose from ∞-solanine was isolated and partially purified by ammonium sulfate precipitation from the peels of Kennebec and Wauseon potatoes. Enzyme activity was found to be present in the 60 to 80% ammonium sulfate fraction. Enzyme activity was increased by the use of non-ionic detergents with a mixture of Triton X-100:Triton CF-54 (2:1, w/w) providing the greatest increase in activity. The pH optimum for the rhamnosidase for both varieties was found to be 6.0 while of the temperatures evaluated 42 °C was the optimum temperature. The effect of substrate concentration on enzyme activity was determined for both varieties and the Vmax and Km were calculated from Lineweaver-Burke double reciprocal plots. The Vmax and Km for the Kennebec and Wauseon rhamnosidases were found to be 0.27 mg/ml and 5.4 x 10-4 M and 0.48 mg/ml and 8.2 x 10-4 M, respectively. 相似文献