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91.
Seung Hun Jeong Hyoung Kyu Kim In-Sung Song Seon Joong Lee Kyung Soo Ko Byoung Doo Rhee Nari Kim Natalia P. Mishchenko Sergey A. Fedoryev Valentin A. Stonik Jin Han 《Marine drugs》2014,12(5):2922-2936
Echinochrome A (Ech A) is a naphthoquinoid pigment from sea urchins that possesses antioxidant, antimicrobial, anti-inflammatory and chelating abilities. Although Ech A is the active substance in the ophthalmic and cardiac drug Histochrome®, its underlying cardioprotective mechanisms are not well understood. In this study, we investigated the protective role of Ech A against toxic agents that induce death of rat cardiac myoblast H9c2 cells and isolated rat cardiomyocytes. We found that the cardiotoxic agents tert-Butyl hydroperoxide (tBHP, organic reactive oxygen species (ROS) inducer), sodium nitroprusside (SNP; anti-hypertension drug), and doxorubicin (anti-cancer drug) caused mitochondrial dysfunction such as increased ROS level and decreased mitochondrial membrane potential. Co-treatment with Ech A, however, prevented this decrease in membrane potential and increase in ROS level. Co-treatment of Ech A also reduced the effects of these cardiotoxic agents on mitochondrial oxidative phosphorylation and adenosine triphosphate level. These findings indicate the therapeutic potential of Ech A for reducing cardiotoxic agent-induced damage. 相似文献
92.
The phase transition behavior and isothermal micro-phase separation kinetics of polyester-based thermoplastic elastomer were
studied using the synchrotron X-ray scattering (SAXS) method. The structural changes occurring during heating period were
investigated by determining the changes of the one-dimensional correlation function, interfacial thickness and Porod constant.
Based on the abrupt increases of the domain spacing and interfacial thickness, a major structural change occurring well below
the melting transition temperature is suggested. Those changes are explained in terms of melting of the thermodynamically
unstable hard domains or/and the interdiffusion of the hard and soft segments in the interfacial regions. SAXS profile changes
during the micro-phase separation process were also clearly observed at various temperatures and the separation rate was found
to be sensitively affected by the temperature. The peak position of maximum scattering intensity stayed constant during the
entire course of the phase separation process. The scattering data during the isothermal phase separation process was interpreted
with the Cahn-Hilliard diffusion equation. The experimental data obtained during the early stage of the phase separation seems
to satisfy the Cahn-Hilliard spinodal mechanism. The transition temperature obtained from the extrapolation of the diffusion
coefficient to zero value turned out to be about 147±2°C, which is close to the order-disorder transition temperature obtained
from the Porod analysis. The transition temperature was also estimated from the invariant growth rate. By extrapolating the
invariant growth rate to zero, a transition temperature of about 145±2°C was obtained. 相似文献
93.
Polyvinyl chloride (PVC) fibers were melt-spun to prepare mono and multifilament yarns. To find optimum spinning and drawing
conditions, various parameters such as spinning temperature, spinneret diameter, drawing temperature, and drawing ratio were
examined. From the observation of the spinnability under various conditions, we found that the optimum conditions were as
following: the extrusion temperature and die temperature were 175–180°C and 185–190°C, and the drawing temperature and drawing
ratio were 85–95°C and 3.4, respectively. Under these conditions, the spinneret diameter could be reduced to the minimum value,
0.5 mm. Spun PVC filament yarns were subjected to the different yarn texturing process of stuffing box and pin false-twist
method. The PVC yarn fabric was prepared by the knitting of textured yarns. Finally, the anion-emission and antibiotic properties
of the knitted PVC fabrics were precisely evaluated. 相似文献
94.
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
95.
Short wool fibers obtained by the stretch breaking process can be blended with cotton fibers and processed in a cotton spinning
system, which has a high production rate. For the structural property of the wool fiber after stretch breaking, the diameter
and length of the wool fiber were measured as a function of time. The diameter of the broken fibers was finer than the diameter
of untreated fibers. The fiber diameter at the break point was the finest and was more irregular than the original fiber.
The broken fiber showed mechanical properties of increased modulus, decreased breaking strain, and increased breaking strength. 相似文献
96.
Doo Hyun Baik Hae Young Kim Sun Jin Kwon Myung Hyun Kwon Han Sup Lee Ji Ho Youk Seung Won Seo 《Fibers and Polymers》2006,7(4):367-371
Thermal properties of copolyetherester/silica nanocomposites were examined by using DSC and TGA. The segmented block copolyetheresters
with various hard segment structures and hard segment contents (HSC) were synthesized and their silica nanocomposite films
were prepared by solution casting method. The nano-sized fumed silica particles were found to act as a nucleating agent of
the copolyetheresters. The nanocomposites always showed reduced degree of supercooling or faster crystallization than the
corresponding copolyetheresters. The nanocomposites also showed increased hard segment crystallinity except HSC 35 sample
which had short hard segment length. In case of 2GT [poly(ethylene terephthalate)] copolyetheresters, which were not developed
commercially because of their low crystallization rate, the hard segment crystallinity increased considerably. The copolyetherester/silica
nanocomposites showed better thermal stability than copolyetheresters. 相似文献
97.
Waterproof fabrics are seamed and sealed by waterproof sealing tape to prevent water from penetrating through the stitch holes.
As this process may change the mechanical properties of breathable waterproof fabric related to its deformation with human
body, the changes in mechanical properties were investigated. In both of parallel and perpendicular directions, tensile characteristics
were remarkably changed with seaming and sealing processes. The increase of LT and WT means that the clothing sealed by waterproofing
tape may produce somewhat discomfort feeling. On the other hand, the bridge of the sewing thread seemed to be reinforced by
waterproofing tape. Shear characteristics such as G, 2HG, and 2HG5 gradually increased with seaming and sealing processes
in parallel direction. However, they decreased with sealing process in perpendicular direction because the seam line work
as an axis located at the center of the testing range. 相似文献
98.
Seung Jae Hwang Iyyakkannu Sivanesan Byoung Ryong Jeong 《Journal of plant nutrition》2013,36(12):2044-2061
ABSTRACT Nutrient uptake over a 72 h culture period by clonal micropropagules of Phalaenopsis Tanigawa × Yukimai Dream ‘KS 370’ and ‘KS 352’ were surveyed by Ichihashi's (1997) nutrient solution at the original ion strength and its half and quarter. Uptake of major anions [nitrate (NO3 ?), phosphate (H2PO4 ?), and sulfate (SO4 2?)] and cations [ammonium (NH4 +), potassium (K+), calcium (Ca2+), and magnesium (Mg2+)] measured with an ion chromatograph increased as the ionic strength of the solution increased in both cultivars. The final uptake rates of nutrients were 0.8, 2.0, 2.1, 1.2, 3.0, 2.0, and 1.6 me L?1, respectively in the order of ions mentioned above. The ratios of the uptake rates between cations (mono or bivalent) were almost in proportion to the ratio of their initial ion strength. Therefore, no antagonistical absorption of cations was found in that ion strength. Leaf content of phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), and copper (Cu) increased as the ionic strength of the solution increased, but concentrations of iron (Fe), manganese (Mn), and zinc (Zn) were not affected significantly. Nitrogen (N) content of leaves in ‘KS 370’ after 72 h culture increased significantly by increasing the ionic strength of the solution. Root concentrations of P, K, Ca, Mg, and Fe increased as the ionic strength of the solution increased in both cultivars. The N concentrations of roots in either ‘KS 370’ or ‘KS 352’ had positive correlations with an increasing ionic strength of the solution, although they were constantly greater in ‘KS 370’ than in ‘KS 352’. The greatest fresh weight was obtained when the plants were cultured in a half strength solution. Whereas dry weight decreased in all treatments as the ionic strength of the solution decreased. These findings show that increased ion absorption affected plant dry weight. The obtained findings provide fundamental information for the closed hydroponic system of phalaenopsis cultivation. 相似文献
99.
Tatsuhiko Matsuguchi Tadao Shimomura Sang Kyu Lee 《Soil Science and Plant Nutrition》2013,59(3):323-336
In the C2H2-C2H4 assay for measurement of heterotrophic N2 fixation in water-logged soils, the diffusion of C2H2 into the soil and the recovery of C2H4 from it are critical factors regulating the assay result. To establish an C2H2-C2H4 assay technique suitable for waterlogged soils, the C2H2-reducing activities (ARA), assayed by varying the method of assay gas filling, the pC2H2 of the assay gas, the duration of assay incubation and of soil vibration before the gas sampling, were compared. A maximum ARA was measured when the following set of procedures were applied to the soil sample in assay flasks: 1) a 4-fold repetition of I-min evacuation under 0.01 atmospheric pressure and the subsequent I-min filling under 1 atmospheric pressure with assay gas at pC2H2 of 0.1 atm, 2) an assay incubation for 3 hr, and 3) a sampling of an aliquot of the headspace gas after strongly vibrating the flask for 1 min. The ARA measured by this technique was several times larger than those measured by the techniques hitherto applied, and corresponded to an almost 80% of the V max of the sample. This technique was, therefore, proposed for the assay of heterotrophic N2 fixation in waterlogged soils. A striking depression of ARA in the soil sample prepared with agitation indicated that a microbial ecosystem established in the soil should be kept as undisturbed as possible throughout the C2H2-C2H4 assay. 相似文献
100.
Rolando A. Flores Carol W. Shanklin Mariano Loza-Garay Seung H. Wie 《Compost science & utilization》2013,21(1):63-71
A survey was undertaken to determine the wastes/residues generated by the food processing industry in the state of Iowa by sending a questionnaire to food processors with more than ten employees. Food processors were asked to provide a company profile, information about food waste/residue generated, and information about current disposal methods. Samples of wastes/residues were obtained from food processors willing to provide them, and proximate analysis was done. The overall response rate was 82.2 percent or 365 respondents out of 444 questioned. Companies under different category of standard industrial code (SIC) could produce similar wastes/residues that were classified in the same waste/residue streams. Within the meat and seafood category, the majority (87.7 percent) of the wastes/residues were generated by SIC codes 2077 (animal, marine fats and oils) and 2015 (poultry slaughtering, dressing, and processing). Among the waste management practices reported, excluding “other,” land application accounted for 14.0 percent of the waste stream, followed by rendering with 11.4 percent, landfill with 6.7 percent, sewage on-site with 5.0 percent and animal feed production off-site with 4.3 percent. Other waste management practices (combinations of major practices or others not clearly defined) account for 55.1 percent of the allocation of the waste stream. 相似文献