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221.
The aim of this study was to find the effect of kale and dietary fibre (DF) on the physicochemical properties, nutritional value and sensory quality of multigrain bars. A recipe of multigrain bars was prepared with the addition of fresh kale (20% and 30%) and DF preparations (apple, blackcurrant, chokeberry and hibiscus). The bars were baked at 180 °C for 20 min. These snack bars, based on pumpkin seeds, sunflower seeds, flaxseed and wholegrain oatmeal, are a high-calorie product (302–367 kcal/100 g). However, the composition of the bars encourages consumption. In addition to the ability to quickly satisfy hunger, such bars are rich in many natural ingredients that are considered pro-health (high fibre content (9.1–11.6 g/100 g), protein (11.2–14.3 g/100 g), fat (17.0–21.1 g/100 g, including unsaturated fatty acids), carbohydrates (20.5–24.0 g/100 g), as well as vitamins, minerals and a large number of substances from the antioxidant group. The addition of kale caused a significant increase of water content, but reduction in the value of all texture parameters (TPA profiles) as well as calorific values. The content of polyphenols was strongly and positively correlated with the antioxidant activity (r = 0.92). In the bars with 30% addition of kale (422 mg GA/100 g d.m.), the content of polyphenols was significantly higher than based ones (334 mg GA/100 g d.m.). Bars with the addition of the DF were characterized by a higher antioxidant activity, and the content of carotenoids, chlorophyll A and B and polyphenols. High sensory quality was demonstrated for all (from 4.8 to 7.1 on a 10-point scale). The addition of fibre preparations was also related to technological aspects and allows to create attractive bars without additional chemicals.  相似文献   
222.
The aim of the study is to evaluate oxidant–antioxidant balance as well as lysosomal and anti-protease activities in ovarian cancer since it has been emphasized that the crucial inducing factor of carcinogenesis may be reactive oxygen/nitrogen species or, more precisely, oxidative stress-induced inflammation. The study involved 15 women with ovarian cancer, aged 59.9 ± 7.8 years, and 9 healthy women aged 56.3 ± 4.3 years (controls). The study material was venous blood collected from fasting subjects. In erythrocytes, the activities of superoxide dismutase, glutathione peroxidase, and catalase, as well as concentrations of conjugated dienes (CDs) and thiobarbituric acid reactive substances (TBARS), were investigated. CD, TBARS, and vitamins A and E plasma concentrations were also determined. Moreover, total antioxidant capacity and concentrations of 4-hydroxynonenal adducts and 8-iso-prostaglandin F2α, as well as activities of acid phosphatase, arylsulfatase, cathepsin D, and α1-antitrypsin, were studied in serum. The vitamin E and 8-iso-prostaglandin F2α concentrations as well as arylsulfatase activity were lower in the women with cancer compared to the controls (p = 0.006, p = 0.03, p = 0.001, respectively). In contrast, cathepsin D activity was lower in the controls (p = 0.04). In the peripheral blood of the women with cancer, oxidant–antioxidant and lysosomal disturbances were observed.  相似文献   
223.
The impedance spectroscopy studies performed for two strongly hydrogen-bonded liquid amides: N-methylpropionamide (NMP, CH(3)·NH·CO·C(2)H(5)) and N-ethylacetamide (NEA, C(2)H(5)·NH·CO·CH(3)) have shown that the two centers of the peptide linkage, -NH·CO-, active in the C=OH-N hydrogen bonds formation, exhibit quite different sensibilities to the steric screening effects. In contrast to the oxygen atom, a relatively small change (CH(3)- to C(2)H(5)-) in the screening of the hydrogen atom leads to an essential decrease of the degree of the amide self-association. As a consequence, both the static dielectric permittivity and the orientational entropy increment of NEA are essentially lower than those of NMP. However, it was found that the dynamic processes studied are only weakly influenced (in the case of dc conductivity, σ(DC)) or totally not influenced (the dielectric relaxation time, τ(D)) by the different degrees of NMP and NEA self-association. The experiment shows that for both the amides, the logσ(DC) vs. logτ(D) dependence is nonlinear and can be described with the fractional Stokes-Einstein-Debye relation, σ(DC)τ ? const, with the exponent s varying from about -0.8 to about -0.6 in the temperature range from 5 °C to 110 °C.  相似文献   
224.
We have found a new structural transition in Pb(2)MnReO(6) at 410 K. Above this temperature, Pb(2)MnReO(6) is cubic with disordered and dynamic atomic displacements manifested in the large thermal parameters of Pb and O atoms. Below 410 K, the antiferrodistortive shift of 2/3 of Pb(2+) cations away from the high-symmetry cubic site produces a new type of monoclinic cell. The unit cell expands at the transition and the heat capacity shows a peak with thermal hysteresis. These features agree with a first order transition. The entropy content of the transition is quite low indicating that the structural disorder has not been completely removed in the low temperature phase. The monoclinic phase of Pb(2)MnReO(6) shows thermally activated conductivity which does not vary when an external magnetic field is applied. A change in the slope of the resistivity curve, observed at the structural phase transition temperature, is related to a slight difference in the activation energy between both phases. It suggests that the condensation of the distortions likely affects the conduction mechanism. The isothermal magnetization measurements reveal the presence of ferromagnetic contributions below 85 K. The ac magnetic susceptibility shows a dynamic peak at 50 K and, in addition, zero-field-cooled and field-cooled magnetization curves diverge strongly below 80 K. These features might be signature of magnetic inhomogeneity. Magnetic loops, obtained at 5 K, do not show saturation in fields up to 9 T. Furthermore, the measured coercivity increases sharply at low temperature indicating an abrupt change in the magnetic anisotropy. We show that all these magnetic properties point out to a ferrimagnetic ordering of Mn and Re atoms in an intermediate valence state.  相似文献   
225.
Highly hydrophilic compounds belonging to biogenic amines were analysed in the reversed-phase system, modified with the addition of ionic liquids: 1-ethyl-3-methyl-imidazolium hexafluorophosphate (EMIM PF(6)) and chaotropic salt NaPF(6) on Discovery HS C18 column at acidic conditions. The effect of the additives concentration and the presence of organic solvent on the analytes' chromatographic parameters such as retention factor, tailing factor and theoretical plates number were all determined. On the basis of k versus ionic liquid concentration in aqueous-organic mobile phase with constant amount of phosphate buffer, retention mechanism was studied. It was established that the presence of organic solvent with low dielectric constant and ionic liquid with both chaotropic ions allows achieving typical Langmuir shape of this relationship. Investigated mobile phase additives are comparable according to efficiency and selectivity towards biogenic amines analysis. However, the sensitivity was found to be better for the eluent system modified with chaotropic salt.  相似文献   
226.
Pilot studies concerning industrial scale application of post copper slag as a nano-additive for the modification of the corrosion resistance of cement composites have been described. The influence of a tribochemical treatment on some physicochemical properties as well as the corrosion resistance of the obtained composites have been evaluated based on DTG, RTG, and SEM coupled with EDX measurements and chemical analysis. It was observed that the so-called “size particle additive effect” influences the course and rate of transformations in the formed cement composites, and may lead to specific and desirable properties.  相似文献   
227.
The optimization of the synthesis of 5-aryl-2-pyrrolidinones through decarbonylation of pyroglutamic acid in Eaton’s reagent, in presence of aromatic derivatives, is described. The utilization of these reaction conditions in the arylation of enaminoester vinylogues (17, 24) of pyroglutamic acid was also realized, confirming that these derivatives are subject to decarbonylationî in the same way as the parent acid. Depending on the nature of the aromatic derivative (15, 21, 28, and 32), two different families of compounds were obtained. Many by-products were also formed, suggesting a utilization of this reaction for compounds more stable than the enaminoesters and enaminonitriles used in this study. The possibility of enaminoesters reacting with aromatics in bimolecular reactions to give enaminoketones should also be noted. Five synthesized compounds were evaluated for their antiproliferative activity on the NCI-60 cancer cell lines panel.  相似文献   
228.
229.
Transport rate of metal cations can be explained by the size of substituents, namely larger substituents such as 7 and 8 prefer Pb(II) cations. The bis-PNP-lariat ethers remove Zn(II), Cd(II) and Pb(II) more efficiently than simple PNP-lariat ethers. The increase of linker length in the bis-PNP-lariat ether molecules lowers the metal cations’ transport rate. In addition, the synergetic effect for lead(II) transport across polymer inclusion membrane (PIM) with PNP-lariat ether 9 and DNNS was using PNP-lariat ethers—carriers 1 and 2 in a PIM system, Zn(II) and Cd(II) were transported with low selectivity from acidic aqueous source phase solutions. The ether 3 used to transport Zn(II) and Cd(II) cations from aqueous phase at pH 5.0 into hydrochloric aqueous solution shows high selectivity of Cd/Zn, but small efficiency of process.  相似文献   
230.
Summary: Surface properties of poly(vinyl alcohol) (PVA) with low content of FeCl3 (1, 5 wt.%) were studied by measurements of contact angles and atomic force microscopy. The results of contact angles and the surface free energy calculations revealed that the hydrophilicity of the surface of PVA films depended on the content of iron (III) chloride in these polymeric films. Introduced salt also affected photochemical reactions in poly(vinyl alcohol). Photooxidation of PVA was more effective in the presence of FeCl3 because of formation of reactive chlorine atoms, which were capable of initiating new reactions. Also the morphology and roughness parameters of PVA film changed when iron (III) chloride was added.  相似文献   
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