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101.
Stinging nettle (Urtica dioica L.) is a good source of biologically active compounds with proven beneficial health effects. This study aimed to investigate the effect of nettle herb supplementation on chemical composition, including the content of selected minerals and pigments, the in vitro glycemic response, and the cooking and sensory quality of extruded pasta. Tagliatelle-shaped pasta was produced under semi-technical scale by partial replacement of durum wheat semolina with 0, 1, 2, 3, 4, and 5% of lyophilized nettle. The partial substitution with freeze-dried nettle caused a statistically significant (p ≤ 0.05) increase in the content of minerals, especially calcium, iron, potassium, and magnesium in the products. The calcium content in the pasta fortified with 5%-addition of stinging nettle was 175.9 mg 100 g−1 and this concentration was 5.8 times higher than in the control sample. At the same time, high content of chlorophylls and carotenoids (237.58 µg g−1 and 13.35 µg g−1, respectively) was noticed. Enriching pasta with a 0–5% addition of stinging nettle resulted in a statistically significant (p ≤ 0.05) increase in the content of the total dietary fiber (TDF) (from 5.1 g 100 g−1 to 8.82 g 100 g−1) and the insoluble dietary fiber (IDF) (from 2.29 g 100 g−1 to 5.63 g 100 g−1). The lowest hydrolysis index of starch (HI = 17.49%) and the lowest glycemic index (GI = 49.31%) were noted for the pasta enriched with 3% nettle.  相似文献   
102.
A series of N‐heterocyclic copper carbene complexes bearing sulfoxide and sulfone moieties have been prepared. In case of new copper compounds with sulfone ligand, the solid‐state structures were determined using X‐Ray crystallography. Obtained complexes were investigated as catalysts in such transformations as: 1,3‐dipolar cycloaddition of alkynes and azides (CuAAC), A3 coupling reaction and β‐hydroboration and compared with standard copper catalytic systems.  相似文献   
103.
The ESRF synchrotron beamline ID22, dedicated to hard X‐ray microanalysis and consisting of the combination of X‐ray fluorescence, X‐ray absorption spectroscopy, diffraction and 2D/3D X‐ray imaging techniques, is one of the most versatile instruments in hard X‐ray microscopy science. This paper describes the present beamline characteristics, recent technical developments, as well as a few scientific examples from recent years of the beamline operation. The upgrade plans to adapt the beamline to the growing needs of the user community are briefly discussed.  相似文献   
104.
The behaviour of thioamides under Kulinkovich-type conditions is compared with the known reactivity of carboxylic amides. Dramatic differences are disclosed.  相似文献   
105.
Multicomponent reactions including Biginelli reaction and A3 coupling are useful synthetic methodologies as they can provide valuable intermediates and building blocks for the synthesis of bioactive natural compounds. The heterocyclic products of these transformations represent antibacterial, antitumor or anti‐inflammatory properties. In presented study, copper‐mediated protocols for Biginelli reaction and A3 coupling in sustainable solvents were reported. At first, charged NHC copper complexes were synthesized in few steps and characterized using spectroscopic methods followed by preliminary activity tests in sustainable media. Later in this study, Biginelli reaction and A3 coupling were proceeded using prepared copper catalytic systems under mild conditions. Desired nitrogen‐bearing products were obtained with moderate to very high yields. Some attempts to recycle one of the received NHC copper initiators were also investigated.  相似文献   
106.
Inductively coupled plasma mass spectrometry was used for characterization of Polish dictyonema shales and sandstones as a potential source of uranium and other technologically important elements. Influence of sample digestion of these materials for the determinations: U, Th, Cu, Co, Mn, Zn, La, V, Yb, Mo, Ni, Sb and Fe has been tested. The method involved two-step microwave acid digestion, followed by direct determination by ICP-MS. The instrument used for all determinations was ELAN DRC II (Perkin Elmer) with crossflow nebulizer with Scott double-pass spray chamber and Ni cones. Certified Reference Materials were used as a quality control standard to validate the applied analytical procedure. The expanded measurement uncertainty U (k = 2) ranged from 5 to 15 %, in dependence on the element. The obtained results provided information on the contents of minor and trace elements in shales and sandstones depending on their origin. At this moment, these geological deposits can be treated as a potential source of raw elements.  相似文献   
107.
The highest yields of biosurfactants were obtained by: (i) Pseudozyma antarctica (107.2 g L?1) cultivated in a medium containing post-refining waste; (ii) Pseudozyma aphidis (77.7 g L?1); and (iii) Starmerella bombicola (93.8 g L?1) both cultivated in a medium with soapstock; (iv)Pichia jadinii (67.3 g L?1) cultivated in a medium supplemented with waste frying oil. It was found that the biosurfactant synthesis yield increased in all strains when the cell surface hydrophobicity reached 70–80 %, enabling the microbial cells to make good contact with hydrophobic substrates. The lowest surface tension of the post-cultivation medium was from 32.0 mN m?1 to 37.8 mN m?1. However, this parameter (which was also determined by a drop collapse assay) was of limited use in monitoring biosurfactant synthesis in this study. The crude glycerol was not a good substrate for biosurfactant synthesis although, in the case of P. aphidis, 67.4 g L?1 of biosurfactants were obtained after cultivation in the medium supplemented with glycerol fraction (GF2). In a low-cost medium containing soapstock and whey permeate or molasses, about 90 g L?1 of mannosylerythritol lipids were synthesised by P. aphidis and approximately 40 g L?1 by P. antarctica.  相似文献   
108.
As microalgae are producers of proteins, lipids, polysaccharides, pigments, vitamins and unique secondary metabolites, microalgal biotechnology has gained attention in recent decades. Microalgae can be used for biomass production and to obtain biotechnologically important products. Here, we present the application of a method of producing a natural, biologically active composite obtained from unicellular microalgae of the genus Planktochlorella sp. as a modulator of the growth of microorganisms that can be used in the cosmetics and pharmaceutical industries by exploiting the phenomenon of photo-reprogramming of metabolism. The combination of red and blue light allows the collection of biomass with unique biochemical profiles, especially fatty acid composition (Patent Application P.429620). The ethanolic and water extracts of algae biomass inhibited the growth of a number of pathogenic bacteria, namely Enterococcus faecalis, Staphylococcus aureus PCM 458, Streptococcus pyogenes PCM 2318, Pseudomonas aeruginosa, Escherichia coli PCM 2209 and Candida albicans ATCC 14053. The algal biocomposite obtained according to our procedure can be used also as a prebiotic supplement. The presented technology may allow the limitation of the use of antibiotics and environmentally harmful chemicals commonly used in preparations against Enterococcus faecalis, Staphylococcus aureus, Streptococcus pyogenes, Pseudomonas aeruginosa, Escherichia coli or Candida spp.  相似文献   
109.
The electrooxidation of short synthetic 20-nucleotides DNA sequences with various amount of guanine molecules has been studied in a wide temperature range by square wave voltammetry and the results were compared with UV-vis and CD spectra. A twofold increase of dsDNA voltammetric peak, related to an increase in the number of electrons transferred in the guanine electrooxidation process was found to begin at a temperature lower by circa 20 °C compared to the well known increase of the dsDNA absorbance upon denaturation. Since the dsDNA voltammetric peaks are related directly to the electrooxidation of guanine and adenine, early conformational changes in dsDNA are responsible for this effect. An increase in percentage of guanine in the DNA chains caused a delay in the conformational, predenaturation changes. An exception to this behavior was found for polyguanine (100% guanine). Interestingly, two distinct ranges of change in ellipticity in the CD spectra correlate well with the changes obtained by voltammetry. We have also checked the influence of OH radicals and UV irradiation on the dsDNA oxidation.  相似文献   
110.
Flavonoids and coumarins are the major bioactive constituents identified in Psoralea corylifolia. The active fraction isolated from fruits, seeds and roots possesses antibacterial, antioxidative and immunomodulatory properties. Neobavaisoflavone is one of the flavonoids found in Psoralea corylifolia. In the present study we investigated in vitro the anti-inflammatory activity of neobavaisoflavone. Macrophages play an important role in inflammation through the release of inflammatory mediators involved in the immune response. Inappropriate and prolonged macrophage activation is largely responsible for the pathology of acute and chronic inflammatory conditions. Neobavaisoflavone significantly inhibited the production of reactive oxygen species (ROS), reactive nitrogen species (RNS) and cytokines: IL-1β, IL-6, IL-12p40, IL-12p70, TNF-α in LPS+IFN-γ- or PMA- stimulated RAW264.7 macrophages.  相似文献   
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