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51.
BACKGROUND: Electrical stimulation (ES) in poultry processing is reported in the literature with varying degrees of effectiveness. Furthermore, the combined effects of ES and polyphosphate marination are not completely known. The objective of this study was to evaluate the combined effect of ES, aging time prior to deboning and phosphate marination on meat quality of broiler breast fillets. RESULTS: The implementation of ES accelerated pH decline in fillets at any aging time studied regardless of marination treatment, but no differences (P > 0.05) were found in pH of fillets deboned without aging. Warner–Bratzler (WB) shear values of ES fillets significantly decreased (P < 0.05) at 2 h of aging whereas WB of non‐ES fillets decreased at 6 h of aging in breast meat, with or without marination. In non‐marinated fillets the ES treatment reduced (P < 0.05) cooking loss in meat aged 0, 2 and 4 h. In marinated fillets the ES treatment decreased cooking loss at 2, 4, 6 and 8 h of aging. CONCLUSION: ES in carcasses aged 2 or 4 h improves tenderness and reduces cooking loss. Marination improves tenderness in both stimulated and non‐stimulated fillets, at all aging times. Copyright © 2012 Society of Chemical Industry  相似文献   
52.
In this study, novel eco-friendly hydrogel adsorbents were synthesized based on poly(vinyl alcohol) (PVA) and different contents of an acid-treated bentonite (1–5 wt %). The hydrogels were prepared by freezing–thawing, which is a simple and nontoxic method. The materials were morphologically and thermally characterized by means of swelling assays, X-ray diffraction, scanning electron microscopy, dynamic scanning calorimetry, and thermogravimetric analysis in order to evaluate the effect of acid-treated bentonite loading. The composite hydrogels showed very distinct porous structure and thermal features in comparison to neat PVA as a consequence of the addition of the clay. Moreover, the performance of the obtained composite hydrogels was tested toward the adsorption of cationic (methylene blue) and anionic dyes (methyl red and methyl orange) from aqueous media. The presence of acid bentonite seems to be beneficial for improving the removal capacity of PVA-based hydrogels. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47663.  相似文献   
53.
The antifungal activity of Pimpinella anisum L. (anise), Pëumus boldus Mol (boldus), Hedeoma multiflora Benth (mountain thyme), Syzygium aromaticum L. (clove), and Lippia turbinate var. integrifolia (griseb) (poleo) essential oils (EOs) against Aspergillus section Flavi was evaluated in sterile maize grain under different water activity (aw) condition (0.982, 0.955, and 0.90). The effect of EOs added to maize grains on growth rate, lag phase, and aflatoxin B1 (AFB1) accumulation of Aspergillus section Flavi were evaluated at different water activity conditions. The five EOs analyzed have been shown to influence lag phase and growth rate. Their efficacy depended mainly on the essential oil concentrations and substrate water activity conditions. All EOs showed significant impact on AFB1 accumulation. This effect was closely dependent on the water activity, concentration, and incubation periods. Important reduction of AFB1 accumulation was observed in the majority of EO treatments at 11 days of incubation. Boldus, poleo, and mountain thyme EO completely inhibited AFB1 at 2000 and 3000 μg g−1. Inhibition of AFB1 accumulation was also observed when aflatoxigenic isolates grew with different concentration of EOs during 35 days.  相似文献   
54.
Injectable bone substitutes (IBS) are increasingly being used in the fields of orthopedics and maxillofacial/oral surgery. The rheological properties of IBS allow for proper and less invasive filling of bony defects. Vaterite is the most unstable crystalline polymorph of calcium carbonate and is known to be able to transform into hydroxyapatite upon contact with an organic fluid (e.g., interstitial body fluid). Two different concentrations of hydrogels based on poly(ethylene glycol)-acetal-dimethacrylat (PEG-a-DMA), i.e., 8% (w/v) (VH-A) or 10% (w/v) (VH-B), were combined with vaterite nanoparticles and implanted in subcutaneous pockets of BALB/c mice for 15 and 30 days. Explants were prepared for histochemical staining and immunohistochemical detection methods to determine macrophage polarization, and energy-dispersive X-ray analysis (EDX) to analyze elemental composition was used for the analysis. The histopathological analysis revealed a comparable moderate tissue reaction to the hydrogels mainly involving macrophages. Moreover, the hydrogels underwent a slow cellular infiltration, revealing a different degradation behavior compared to other IBS. The immunohistochemical detection showed that M1 macrophages were mainly found at the material surfaces being involved in the cell-mediated degradation and tissue integration, while M2 macrophages were predominantly found within the reactive connective tissue. Furthermore, the histomorphometrical analysis revealed balanced numbers of pro- and anti-inflammatory macrophages, demonstrating that both hydrogels are favorable materials for bone tissue regeneration. Finally, the EDX analysis showed a stepwise transformation of the vaterite particle into hydroxyapatite. Overall, the results of the present study demonstrate that hydrogels including nano-vaterite particles are biocompatible and suitable for bone tissue regeneration applications.  相似文献   
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The operations of the group feeding programs (PAG--"Programas de Alimentación a Grupos"--) can be viewed as a sequence of decisions and activities that according to their direction, order, relationship and dependency, will influence the quality and quantity of the service's delivery. While searching for the essential characteristics of a PAG: components, relationship, variables, pertinent parameters, restrictions, underlying criteria and objective functions, operations research can be useful for its analysis, the identification of its management problems, and to develop, evaluate and finally, implement solutions. Various operation research techniques are presented in this article, which are geared towards responding to those knowledge needs of the national technicians and program managers, in order to give a solid foundation to solutions for the management problems identified in a PAG. Failures of different quantitative models had been due, mainly, to the tendency to formulate models or investigate problems without users being prepared to implement the solutions. The techniques presented herein take into consideration the interaction between specialists and users.  相似文献   
57.
Universal Access in the Information Society - Although geo-crowdsourcing approaches provide an opportunity to collect and share environmental accessibility information for people with disabilities,...  相似文献   
58.
Fatty acids, tocopherols, and phenolic compounds biogenesis from two major Spanish olive cultivars (Arbequina and Manzanilla) were analyzed for the function of the thermal regime during the fruit ontogeny in a non‐Mediterranean environment. Bilinear models characterized the dynamics of fatty acid biogenesis. Regressions between the accumulated thermal time (TT) and the levels of both oleic and linoleic acids showed different responses to temperature of each olive cultivar. After reaching similar absolute maximum oleic acid contents at similar TT, the levels of this fatty acid decreased markedly in cv. Arbequina and its final concentration was 10 % lower than that found in cv. Manzanilla. In both cultivars, concentrations of all tocopherol isoforms were negatively associated with the TT accumulated over the entire oil accumulation period. Dynamics of phenolic compounds biogenesis showed no clear tendencies with TT. Nevertheless, and whatever the stage of fruit development, secoiridoids were the major phenolic components. Results suggest greater sensitivity of fatty acid metabolism to temperature in cv. Arbequina. This fact points out the necessity of appropriate evaluation of the ambient thermal characteristics before introducing this cultivar into new growing environments.  相似文献   
59.
Sugarcane bagasse is the major by-product of the sugarcane industry, and it can serve as a substrate for biotechnological processes for obtaining value-added products. This study gave multiple adding values to sugarcane bagasse using it in two separate bioprocesses. Sugarcane bagasse was used as a substrate for enzymatic cocktail production from Auricularia fuscosuccinea LBM 244 and as a source of proteins and phenolic compounds. A. fuscosuccinea LBM 244 enzyme cocktail-assisted extraction, commercial enzyme assisted extraction and conventional extraction were compared. Enzymatic-assisted extractions released 557–827% more protein content than those at 0 h. A. fuscosuccinea LBM 244 enzyme cocktail released 50% and 30% phenolic compounds more than conventional and commercial enzyme extraction, respectively. These phenolic compounds were represented mainly by ρ-coumaric and ferulic acids. On top of that, the cost of the enzymes in enzyme-assisted extraction was reduced fourfold using the A. fuscosuccinea LBM 244 enzyme cocktail.  相似文献   
60.
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