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BACKGROUND: The effects of bud load on the quality of Beogradska besemena and Thompson seedless table grape cultivars were studied. Two pruning treatments were imposed: 44 and 18 buds per vine for Beogradska besemena and 44 and 22 buds per vine for Thompson seedless. RESULTS: In Beogradska besemena the reduction of bud load decreased titratable acidity (?4%), skin dry weight (?16%) and malic and citric acid contents (?43 and ? 20%) and increased tartaric acid content (14%). The decrease in pulp antioxidant activity (?36%) was related to the decrease in hydroxycinnamoyl tartaric acid content (?13%). Concerning skin, the reduction of bud load decreased catechin and caffeoyl tartaric acid contents (?42 and ? 40%) and significantly increased rutin and quercetin‐3‐O‐glucopyranoside contents as specific compounds and flavonoids and proanthocyanidins (9 and 21%) as classes of compounds, thus causing an increase in antioxidant activity (6%). In Thompson seedless the reduction of bud load increased soluble solid content (7%), acidity (9%) and concentrations of the three organic acids (7, 3 and 14%). The increase in pulp antioxidant activity (25%) could be attributed to the increase in total phenolics (69%). The reduction of bud load caused a significant decrease in quercetin‐3‐O‐glucopyranoside (?26%) and antioxidant activity (?15%) in skin. Principal component analysis allowed good separation between samples of the two cultivars, independently of bud level. CONCLUSION: The results indicate that the effects of different bud loads are cultivar‐dependent. Bud load and genotype differences were shown to dramatically impact the quality and antioxidant properties of table grape. Copyright © 2011 Society of Chemical Industry  相似文献   
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Topographic patterns are known to affect cellular processes such as adhesion, migration and differentiation. However, the optimal way to deliver topographic signals to provide cells with precise instructions has not been defined yet. In this work, we hypothesize that topographic patterns may be able to control the sensing and adhesion machinery of cells when their interval features are tuned on the characteristic lengths of filopodial probing and focal adhesions (FAs). Features separated by distance beyond the length of filopodia cannot be readily perceived; therefore, the formation of new adhesions is discouraged. If, however, topographic features are separated by a distance within the reach of filopodia extension, cells can establish contact between adjacent topographic islands. In the latter case, cell adhesion and polarization rely upon the growth of FAs occurring on a specific length scale that depends on the chemical properties of the surface. Topographic patterns and chemical properties may interfere with the growth of FAs, thus making adhesions unstable. To test this hypothesis, we fabricated different micropatterned surfaces displaying feature dimensions and adhesive properties able to interfere with the filopodial sensing and the adhesion maturation, selectively. Our data demonstrate that it is possible to exert a potent control on cell adhesion, elongation and migration by tuning topographic features’ dimensions and surface chemistry.  相似文献   
135.
This paper introduces an adapted high-speed high pressure torsion (HS-HPT) method of severe plastic deformation applied for obtaining shape memory alloy (SMA) active elements with revolution symmetry, able to develop axial displacement/force. Billets with circular crown forms were cut from Fe-28Mn-6Si-5Cr (mass%) SMA ingots and, by means of HS-HPT technology, were directly turned into modules, with truncated cone shell configurations. This process was performed, during time intervals of seconds, under the effect of high pressure (up to 1 GPa) cumulated with high rotation speed (hundreds of rotations per minute) applied on the active surfaces of sintered-carbide anvils, specially designed for this purpose. Due to pressure and friction, generated by rotation, the entire sample volume is heated and simultaneously deformed to final shape. During the process, microstructure fragmentation occurred enabling to obtain (ultra)fine grains and nanocrystalline areas, in spite of the heat developed by friction, which was removed by conduction at the contact surface between sample and anvils, before the occurrence of any recrystallization phenomena. When compressed between flat surfaces, the truncated cone modules developed a superelastic-like response, unique among Fe-Mn-Si base SMAs and, when heated in compressed state, they were able to develop either axial strokes or recovery forces by either free or constrained recovery shape memory effect (SME), respectively. By means of optical (OM) and scanning electron microscopy (SEM) marked structural changes caused by HT-HPT were revealed, along with fine and ultrafine crystalline grains. The presence of stress-induced ε-hexagonal close-packed (hcp) martensite, together with nanocrystalline areas were confirmed by x-ray diffraction.  相似文献   
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There is increasing evidence to suggest that extracellular matrix (ECM) components play an active role in tumor progression and are an important determinant for the growth and progression of solid tumors. Tumor cells interfere with the normal programming of ECM biosynthesis and can extensively modify the structure and composition of the matrix. In ovarian cancer alterations in the extracellular environment are critical for tumor initiation and progression and intra-peritoneal dissemination. ECM molecules including versican and hyaluronan (HA) which interacts with the HA receptor, CD44, have been shown to play critical roles in ovarian cancer metastasis. This review focuses on versican, HA, and CD44 and their potential as therapeutic targets for ovarian cancer.  相似文献   
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Blends of a commercial polypropylene (PP), typically used as food contact material, with increasing amounts of poly(4‐methyl‐1‐pentene) (PMP) are prepared in a twin‐screw extruder to obtain thin films with improved gas permeation for fresh vegetable packaging. Permeability, haze, and transparency of monolayer films produced by casting are investigated under conditions mimicking the industrial ones. O2 and CO2 permeability can be tuned by increasing PMP content in the blends from 5 to 20 wt %. Transparency and haze are practically unchanged in the presence of low content of PMP. Moreover, tensile and rheological tests show that PMP does not significantly affect the related properties of blends compared to the neat PP matrix, thus allowing for the industrial applicability of these new formulations. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2014 , 131, 39503.  相似文献   
139.
Lipid transfer protein (LTP, Pru p 3) is the major allergen of peach (Prunus persica), and is in a greater abundance in the peel than in the pulp of the fruit. Peel LTP is more allergenic than pulp LTP, but it is not clear whether this is due to its specific allergenic properties or to its higher concentration.  相似文献   
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