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81.
Barley has long been known as a good source of fibre and in particular beta-glucan, but increased consumer awareness has meant that this is only now being exploited by food scientists and the food industry. In this study, doughs and breads were produced using pearled barley flour (PBF) in different ratios (30, 50, 70 and 100%) to wheat flour. A 100% wheat flour formulation was used as a control. The flour formulations were evaluated for protein content; the dough rheological properties of the formulations were evaluated using fundamental oscillatory tests and uniaxial extension tests. The baked breads were evaluated for volume, texture, moisture, dietary fibre and beta-glucan. Digital image analysis of the crumb grain was also carried out. Protein analysis revealed that increasing the amount of PBF in the formulation leads to a significant (p < 0.001) decrease in the protein content of the formulation. Starch pasting properties were also affected by an increase in PBF concentration, with an increase in PBF significantly increasing the peak viscosity, breakdown, setback and final viscosity of the starch slurries of the formulations. Extensional rheology revealed that increasing the PBF in the doughs leads to the doughs rupturing at lower extensions and with a lower force. Bread volume between treatments was found to be significantly (p ≤ 0.001) different, with an increase in PBF inclusion leading to smaller loaves. Texture profile analysis of the bread slices showed that breads containing higher ratios of PBF had a significantly harder (p ≤ 0.001) and less cohesive (p ≤ 0.001) crumb. Low levels of PBF (≤50%) did not significantly effect loaf volume or crumb texture, however, and the total dietary fibre and beta-glucan levels of the loaves were significantly increased (p ≤ 0.001) with increasing levels of PBF in the formulation, even at low levels of inclusion.  相似文献   
82.
The use of sourdough in wheat and rye breads has been extensively studied; however, little is known about its potential effect when baking oat bread. Consequently, the impact of sourdough on oat bread quality was investigated. Two different sourdoughs were prepared from wholegrain oat flour without the addition of starter cultures, by continuous propagation at 28 (SD 28) or 37 °C (SD 37) until the composition of the lactic acid bacteria remained stable. The dominant LAB were identified by sequence analysis of the 16S rDNA isolated from pure cultures. LAB from SD 28 belonged to the species Leuconostoc argentinum, Pedicoccus pentosaceus and Weissella cibaria, while Lactobacillus coryniformis dominated SD 37. The isolated LAB were further used as starter cultures for the production of oat sourdoughs. Fundamental rheology revealed softening of the sourdoughs compared to non-acidified and chemically acidified controls, which could not be attributed to proteolytic activity. Incorporation of oat sourdough into an oat bread recipe resulted in significantly increased loaf-specific volume as well as improved texture, independent of addition level or sourdough type. Overall, the results of this study show that sourdoughs containing lactic acid bacteria isolated from oats have the potential to enhance oat bread quality.  相似文献   
83.
Direct stimulation of soluble guanylate cyclase (sGC) represents a promising therapeutic strategy for the treatment of a range of diseases, including the severely disabling pulmonary hypertension (PH). Optimization of the unfavorable DMPK profile of previous sGC stimulators provided riociguat, which is currently being investigated in phase III clinical trials for the oral treatment of PH.

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84.
Thermal comfort and satisfaction at workplaces – a field study in office buildings. By applying multivariate analysis to survey data of a field study in 17 buildings, several correlations between different parameters with regard to satisfaction at workplaces could be found and validated. One important result was that the individual satisfaction parameters were independent. A significant difference between winter and summer votes on the satisfaction with the indoor temperature could be shown; the dissatisfaction at neutral thermal sensation was considerably higher in summer. In total, only 30% of the occupants were very satisfied or satisfied with the temperature at their workplace in summer and winter. The perceived effectiveness of attempted temperature changes proofed to be the dominant parameter for the satisfaction with the indoor temperature. By weighting individual satisfaction parameters a matrix could be generated which provides a straight‐forward assessment of building performance by showing the optimisation potential for each parameter and the necessity to act for the building manager. The conclusion with regard to building design is that small office rooms with individual control of the indoor environment perform best in terms of acceptance by occupants.  相似文献   
85.
The Hagberg falling number (HFN) is one of the most important quality characteristics of wheat. Six winter wheat cultivars from three locations in Germany were analysed to assess the factors influencing the HFN. The cultivars and locations affected significantly the HFN of all the samples. The infection with Fusarium culmorum, determined in another cultivar, also led to an increase in HFN, which suggested that the HFN method is not adequate enough for the true determination of the alpha-amylase activity of fungus-infected, wheat flour. Furthermore, there was no clear correlation between HFN and thousand-kernel weight, starch content or pentosan content. The crude protein content was positively related to the HFN, while the total dietary fibre content depended on the cultivar and location.  相似文献   
86.
Modifications of fruit quality, in response to a long-term salt stress of four months, were studied in two strawberry cultivars differing in their sensitivity to salinity. The sensitive cv. Elsanta and the less sensitive cv. Korona were treated during two vegetation seasons with 0, 40 or 80 mmol NaCl/l in the nutrient solution. While mean fruit weight decreased, dry matter and contents of total soluble carbohydrates, as well as sweetness index of fruits, remained constant. Salt stress in both cultivars increased the antioxidant capacity, antioxidants pools (ascorbic acid, anthocyanins, superoxide dismutase) and selected minerals such as Na+, Cl, K+, N, P and Zn2+, as well as lipid peroxidation. Furthermore, salt stress increased the contents of free and essential amino acids, especially in cv. Elsanta. The more tolerant cv. Korona was characterized by an increase of reduced glutathione and a better fruit taste. In salt-stressed fruits of cv. Elsanta, taste was significantly impaired.  相似文献   
87.
Strawberry cvs Korona and Elsanta, differing in their sensitivity to salt stress, were exposed to 0, 40, or 80 mM NaCl in the root medium from the end of April to mid-August. Although fruits of both cultivars contained comparable amounts of Na+ and Cl, fruit quality was more impaired in cv. Elsanta, as indicated by the larger reductions of fruit size and sugar/acid ratios. Malondialdehyde levels started to rise significantly at 40 mM NaCl in the more sensitive cv. Elsanta, but at 80 mM in cv. Korona. Total amino acid levels, especially contents of essential amino acids, rose significantly in both cvs. Salt stress also increased contents of free proline, asparagine, and glutamine. Their increases may contribute to osmotic adjustment. The results of the present study favour the interpretation that elevated levels of proline, asparagine and glutamine are indicative of salt stress damage.  相似文献   
88.
89.
Interface‐induced modifications of the electronic, magnetic, and lattice degrees of freedom drive an array of novel physical properties in oxide heterostructures. Here, large changes in metal–oxygen band hybridization, as measured in the oxygen ligand hole density, are induced as a result of interfacing two isovalent correlated oxides. Using resonant X‐ray reflectivity, a superlattice of SrFeO3 and CaFeO3 is shown to exhibit an electronic character that spatially evolves from strongly O‐like in SrFeO3 to strongly Fe‐like in CaFeO3. This alternating degree of Fe electronic character is correlated with a modulation of an Fe 3d orbital polarization, giving rise to an orbital superstructure. At the SrFeO3/CaFeO3 interfaces, the ligand hole density and orbital polarization reconstruct in a single unit cell of CaFeO3, demonstrating how the mismatch in these electronic parameters is accommodated at the interface. These results provide new insight into how the orbital character of electrons is altered by correlated oxide interfaces and lays out a broadly applicable approach for depth‐resolving band hybridization.  相似文献   
90.
The tropical diseases human African trypanosomiasis, Chagas disease, and the various forms of leishmaniasis are caused by parasites of the family of trypanosomatids. These protozoa possess a unique redox metabolism based on trypanothione and trypanothione reductase (TR), making TR a promising drug target. We report the optimization of properties and potency of cyclohexylpyrrolidine inhibitors of TR by structure‐based design. The best inhibitors were freely soluble and showed competitive inhibition constants (Ki) against Trypanosoma (T.) brucei TR and T. cruzi TR and in vitro activities (half‐maximal inhibitory concentration, IC50) against these parasites in the low micromolar range, with high selectivity against human glutathione reductase. X‐ray co‐crystal structures confirmed the binding of the ligands to the hydrophobic wall of the “mepacrine binding site” with the new, solubility‐providing vectors oriented toward the surface of the large active site.  相似文献   
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