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91.
This paper suggests the optimal conditions to prevent electrostatic charge in the laundry by the evaluation of the electrostatic characteristics during the drying process. Cotton, nylon, and polyester fabrics were used as test specimens, employing the standard washing cycle. The electrostatic characteristics of the laundry were measured after the automatic drying process. This paper investigates the optimal conditions for preventing electrostatic charges in laundry by evaluating the electrostatic characteristics that occur during the drying process. Cotton, nylon, and polyester fabrics were used as the test specimens, employing a standard washing cycle. The electrostatic characteristics of the laundry were measured immediately after the automatic drying process. The results, showed that the moisture content decreased and the electrostatic charge increased with drying time. The specimen fabrics had already dried up before completion of the standard drying cycle. Consequently, the excessive drying generated an electrostatic charge due to removal of the traces of remaining moisture and the resulting excessive friction. For cotton fabrics, the electrostatic charge was under 1000 V even for the maximum drying time due to the intrinsic high moisture regain of cotton. On the other hand, the electrostatic charge produced for nylon fabrics increased rapidly with the drying time, and amounted up to approximately 8000V after 120 minutes. The results also indicated that the electrostatic charge could be decreased by drying fabrics of only one kind. When mixed kinds of fabrics were dried, the electrostatic charge increased remarkably. Therefore, it is suggested that laundry be classified and washed according to the kinds of fiber, and not be dried excessively to reduce electrostatic charge. In addition, the proper use of a softener is effective in reducing the electrostatic charge.  相似文献   
92.
Surface modification of polyester fabrics by enzyme treatment   总被引:1,自引:0,他引:1  
In this study, the effect of enzymatic hydrolysis using lipase and cutinase on poly(ethyleneterephthalate) (PET) fabrics was investigated in an attempt to improve the hydrophilicity of these fabrics. The hydrolytic activity of the enzymes was expressed for variations in pH levels, temperatures, enzyme concentrations, and treatment times. The effects of using a nonionic surfactant were examined by measuring moisture regain and surface wettability. Finally, the fabric characteristics that were affected by enzyme treatment were evaluated by tensile strength and scanning electron microscopy. The optimal treatment conditions for lipase were determined to be a pH of 4.2, a temperature of 50 °C, a lipase concentration of 100 %, and a treatment time of 90 min; those for cutinase were determined to be a pH of 9.0, a temperature of 50 °C, a cutinase concentration of 100 %, and a treatment time of 60 min. At optimal enzymatic treatment conditions, we got the significant results of increase on the moisture regain and the water contact angle (WCA) and water absorbency effectively decreased. Triton X-100 facilitated cutinase hydrolysis on PET fabrics; however, it was ineffective for lipase. With enzymatic treatment, the tensile strength did not decrease.  相似文献   
93.
Lotus-leaf-like nanofibrous surfaces were prepared by electrospinning hydrophobic poly(vinylidene fluoride) (PVDF) from a mixed solvent of N,N-dimethylformamide (DMF) and acetone. PVDF fibrous mats with a bead-on-string morphology were generated because the nonpolar acetone decresed the viscosity of the PVDF solution and promoted the evaporation of the solution during electrospinning process. The morphology of the nanofibirous surface was examined by scanning electron microscopy. Micron-sized beads were introduced to the electrospun PVDF mats, resulting in enhanced hydrophobicity of the electrospun mats. The addition of a small amount (0.05 vol%) of acetic acid to the polymer solution effectively improved the bead-on-string morphology of the electrospun mats, and led to a higher water contact angle (WCA). The electrospun PVDF fibrous mat showed a maximum WCA of 148.5° due to the appropriate surface roughness.  相似文献   
94.
The miscibility and crystallization behavior of the blends of poly(vinylidene fluoride) (PVDF) and ethylene/vinyl acetate(20/80) copolymer (EVAc80) have been studied using a differential scanning calorimeter and a polarizing microscope equipped with a heating stage. From the melting point depression, the values of interaction energy densityB were calculated to be −1.3004 (cal/cm3) and the Flory-Huggins interaction parameterχ 12 was found to be −0.0818 at 445.6 K. With increasing concentration of EVAc80, the radial growth rate of spherulite was reduced drastically. The FT-IR analysis of samples quenched from the melt to various temperatures showed increasing content ofβ-phase with increasing amount of blended EVA80 along with lower quenching temperature.  相似文献   
95.
Vacuum drying was employed with a vacuum impregnation technique in a semidry state to enrich rice with antioxidants of beetroot juice. The properties of the vacuum‐dried raw and cooked rice grains were characterized. The various raw rice grains (three varieties and two storage time periods) exhibited a significant absorption of beetroot juice, which was evident from the red‐violet beetroot color of the rice, as distinguished from the white color of the control. The color increase (ΔE= 20−40) was linear with the juice content (R2 = 0.96−0.99). Their total phenolic (TP) contents and 2,2‐diphenyl‐2‐picrylhydrazyl radical (DPPH) scavenging activities were enhanced (ΔTP = 21−260 mg of gallic acid equivalents/100 g of rice db and ΔDPPH = 22−64 mg of vitamin C equivalents/100 g of rice db). Their grain integrity was reduced (Δforce = −1 to −63), which was potentially associated with the formation of grain surface cracks (linear relationship of %crack and %juice with R2 = 0.94−0.98). After cooking, the enriched rice grains were linearly elongated with added juice (R2 = 0.88−0.97, up to 1.6‐, 2.0‐, and 2.0‐fold for Sanpatong 1, Khao Dawk Mali 105, and Chainart 1 rice samples, respectively), and the overall volume of the cooked rice was increased (likely not linear, up to 3.2‐, 4.3‐, and 4.8‐fold for Sanpatong 1, Khao Dawk Mali 105, and Chainart 1 rice samples, respectively). Such improvements in cooking qualities were obtained by this simple vacuum‐drying technique, in comparison to existing rice‐aging processes that are more time consuming. The sensorial scores of the resultant rice products were excellent. Vacuum drying is an effective tool to improve the antioxidant value of rice as well as its cooking quality, and the raw quality remains appreciable. It is a simple and rapid process that could be practical for manufacturing healthy rice products.  相似文献   
96.
Inhibition of acyl CoA:diacylglycerol acyltransferase (DGAT), which is a key enzyme in triglyceride synthesis in eukaryotic organisms, has been proposed as one of the drug targets for treating obesity, type II diabetes mellitus, and metabolic syndrome. Bioassay-guided fractionation of EtOH extract of the flower buds of Tussilago farfara , using an in vitro DGAT enzyme assay, resulted in the isolation of four known sesquiterpenoids, tussilagonone (1), tussilagone (2), 7beta-(3-ethyl-cis-crotonoyloxy)-1alpha-(2-methylbutyryloxy)-3,14-dehydro-Z-notonipetranone (3), and 8-angeloylxy-3,4-epoxy-bisabola-7(14),10-dien-2-one (4). DGAT1 inhibitory activity was studied by in vitro DGAT assay using rat liver microsomes and HepG2 cell microsomes. They showed DGAT1 inhibition with IC(50) values of 99.2 (1), 18.8 (2), 47.0 (3), and 211.1 (4) microM (for rat liver microsomes) and >1 mM (1), 49.1 (2), 160.7 (3), and 294.4 (4) microM (for HepG2 cell microsomes), respectively. Compound 2 showed the most potent inhibition against microsomal DGAT1 derived from rat liver and human hepatocellular carcinoma HepG2 cells and also significantly inhibited triglyceride synthesis by suppressing incorporation of [(14)C]acetate or [(14)C]glycerol into triglycerides in HepG2 cells. These findings suggest that tussilagone is a potential lead compound in the treatment of obesity and type 2 diabetes.  相似文献   
97.
Onion plants synthesize flavonoids as protection against damage by UV radiation and by intracellular hydrogen peroxide. Because flavonoids also exhibit health-promoting effects in humans, a need exists to measure their content in onions and in processed onion products. To contribute to the knowledge about the levels of onion flavonoids, HPLC and LC-MS were used to measure levels of seven quercetin and isorhamnetin glucosides in four Korean commercial onion bulb varieties and their distribution within the onion, in scales of field-grown onions exposed to home processing or to fluorescent light and in 16 commercial dehydrated onion products sold in the United States. Small onions had higher flavonoid content per kilogram than large ones. There was a graduated decrease in the distribution of the flavonoids across an onion bulb from the first (outside) to the seventh (innermost) scale. Commercial, dehydrated onion products contained low amounts or no flavonoids. Losses of onion flavonoids subjected to "cooking" (in percent) ranged as follows: frying, 33; sauteing, 21; boiling, 14-20; steaming, 14; microwaving, 4; baking, 0. Exposure to fluorescent light for 24 and 48 h induced time-dependent increases in the flavonoid content. The results extend the knowledge about the distribution of flavonoids in fresh and processed onions.  相似文献   
98.
The effective utilization of crop diversity held in genebanks depends on our knowledge of useful traits and available markers associated with the target traits. Target region amplification polymorphism (TRAP) was used to evaluate the genetic diversity and underlying relationships among 263 accessions of chickpea landraces maintained by the USDA-ARS Western Regional Plant Introduction Station in Pullman, WA, USA. Two-hundred sixty-two TRAP markers were amplified by eight primer combinations. Altogether, 110 (42 %) markers were polymorphic, the other 152 (58 %) displayed no variation. These polymorphic markers revealed important differences among the accessions, with an estimated, mean pair-wise genetic distance of 25.82 %, ranging from 2.8 to 50.0 %. Genetic distance analysis divided the accessions into two major groups, with 113 and 150 accessions each, and substantial association between molecular diversity and geographic origin was evident. Bayesian analysis of population structure revealed two groups (K = 2) with evidence for six sub-groups. Additionally, the population structure of a subset of 110 lines was determined (K = 3) for testing marker-trait associations (MTAs). Phenotypic traits included the concentrations of protein and nine mineral elements in the seeds. Two MTAs were significant (p < 0.01) for concentrations of Ca and K, and three MTAs were significant for Cu and Ni concentrations. The results indicate that this population is useful for genome-wide association studies on other economic traits given the level of genetic diversity uncovered and the marker-trait associations in seed minerals discovered.  相似文献   
99.
To investigate the aluminum deposition on the chemically recycled polyethylene terephthalate (CR-PET) fabrics by DC magnetron sputtering, effects of sputtering parameters (sputtering power and deposit time) on the properties of the Al deposited CR-PET fabric were examined. The variations in the properties such as wettability, optical and thermal insulation property of the CR-PET fabric sputtered under various sputtering parameters were discussed. Wettability of the Al deposited CR-PET fabrics decreased with an increase of sputtering power and deposit time, and then they leveled off above a certain condition. The light reflectance of the Al deposited CR-PET fabrics showed a maximum point with proper sputtering power and deposition time. The thermal insulation property of the Al deposited CR-PET fabrics improved with sputtering power and deposit time.  相似文献   
100.
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