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121.
Beer is the most consumed alcoholic beverage in the world. The purpose was to compare the effects of consuming alcoholic beer (AB) and nonalcoholic beer (NAB) on the biochemical blood parameters. Two beers were produced under known and controlled conditions from the same raw material, NAB (0.6%, v/v) and AB with the addition of 6% grain alcohol. Fifteen healthy adult men (aged 20 to 57 y) underwent 3 treatments (30 d per treatment). In Treatment 1 (Baseline), they followed their usual diet without drinking any alcoholic beverage; in Treatment 2, they added the daily consumption of 330 mL NAB; and in Treatment 3, they added the daily consumption of 330 mL AB. It was found that the use of AB for 30 d (16 g alcohol/d) reduced the blood insulin and fasting glucose, reducing insulin resistance. These data suggest that the daily intake of 330 mL AB could statistically change the lipid profile and insulin sensitivity of adult men. The volunteers were healthy before and remained so after the intervention, with no change in their clinical status.  相似文献   
122.
The basis of the design of earth and rockfill dams is focused on ensuring the stability of the structure under a set of conditions expected to occur during its life. Combined mechanical and hydraulic conditions must be considered since pore pressures develop during construction, after impoundment and in drawdown. Other instability phenomena caused by transient flow and internal erosion must be considered. The prediction of the hydro-mechanical behavior of traditional and non-traditional materials used in the construction of dams is therefore fundamental. The materials used for dam’s construction cover a wide range from clayey materials to rockfill. In a broad sense they are compacted materials and therefore unsaturated materials. A summary of the current level of knowledge on the behavior of traditional materials used in the construction of dams is presented in the paper. Regular compacted materials (with a significant clay fraction), rockfill and compacted soft rocks are studied with more detail. The latter are non-traditional materials. They are analysed because their use, as well as the use of mixtures of soil and rock, is becoming more necessary for sustainability reasons.  相似文献   
123.
We report on (magneto-) transport measurements of individual In2O3 nanowires. We observed that the presence of a weak disorder arising from doping and electron-boundary collisions leads to weak localization of electrons as revealed by the positive magnetoconductivity in a large range of temperatures ( approximately 77 K). From temperature-dependent resistance and magnetoconductivity data, the electron-electron interaction was pointed out as the mechanism responsible for the increase of resistance in the low temperature range and the dominant source of the dephasing at low temperatures. The experimental data provided the phase coherence time tau(phi) approximately T(-2/3) expected for 1D systems, giving consistent support to the mechanisms underlying the weak-localization and electron-electron scattering theories.  相似文献   
124.
This paper describes a method developed to evaluate the seismic performance of old masonry buildings, which allows identifying the expected structural collapse mechanism of the structure. The collapse mechanism is identified by the accumulation of several damaged structural elements in specific points of the structure. The methodology allows simulating the non-linear behaviour of masonry buildings by making use of an iterative procedure, where the structure is changed at each step according to the cracking, yielding or collapse of structural elements at the previous steps. The method was applied to an old masonry building from the city of Lisbon that includes a three-dimensional timber structure enclosed in masonry walls aimed at providing seismic resistance. Discussion is made regarding the advantages of the iterative procedure for the identification of the expected structural collapse mechanism of old masonry buildings. The method limitations will also be discussed.  相似文献   
125.
Wine proteins play an important role in different characteristics of wine (e.g., aroma and body, foaming in sparkling wines). They can also cause a number of technological problems during vinification and may be responsible for the appearance of turbidity in bottled wine. These important features of proteins in wine have made necessary the development of new and fast analytical methods that can provide deeper knowledge about these biopolymers. However, separation and characterization of wine proteins is difficult and time-consuming mainly due to their low concentration and large number of interfering compounds. Besides, long sample preparation protocols can bring about protein decomposition. This paper proposes a new and fast method for carrying out the analysis of the protein fraction of wines. The procedure consists of direct treatment of wine using a centrifugal filter device (CFD), denaturation of the proteinaceous fraction with sodium dodecyl sulfate (SDS) and 2-mercaptoethanol, and subsequent CGE analysis of SDS-proteins. Results on the molecular weight (Mw) and relative quantity of proteins of wines are attained in about 1 h with this procedure. The method is applied to analyze different wines from Canary Islands. To our knowledge, this is the first report of separation of wine proteins according to their Mw by CGE.  相似文献   
126.
Awareness of consumers about phenolic compounds and their positive role in human nutrition is increasing nowadays. Therefore, studies with large number of samples for determination of the effect of agronomic or processing conditions on phenolic composition of foods are arising on importance. This work describes a validated HPLC-DAD method for simultaneous quantification of ten intact phenolic compounds, including phenolic acids and flavonoids (4-caffeoylquinic acid, 5-caffeoylquinic acid, dicaffeoylquinic acids I and II, tricaffeoylquinic acid, quercetin trisaccharide, quercetin-3-O-rutinoside, kaempferol-3-O-rutinoside, naringenin, and naringenin chalcone), in tomato fruit extracts. Extraction treatment and chromatographic system were chosen with the aim of minimizing time, equipment, and disposable costs in laboratory. Method was applied for characterization, for the first time, of three Spanish tomato cultivars (“Caramba”, “Montserrat”, and “Pera de Girona”) which showed significant differences in their phenolic content. Validation parameters for the compounds with commercially available standards (91–105% accuracy; 68–97% recovery; 5–90 μg/kg LOQ; <10% RSD repeatability; >0.99 r 2 for calibration curves; 5,500–115,000 N) can be considered suitable for practical purposes in high-throughput analysis.  相似文献   
127.
Hyaluronic acid is a hydrophilic mucopolysaccharide composed of alternating units of D-glucuronic acid and N-acetylglucosamine. It is used in many medical, pharmaceutical, and cosmetic applications, as sponges, films, or particle formulations. Hyaluronic acid nanoparticles can be synthesized free of oil and surfactants by nanoprecipitation in organic solvents, followed by chemical crosslinking. The organic solvent plays an important role in particles size and structure. Therefore, this study aimed to investigate the influence of acetone, ethanol, and isopropyl alcohol on the synthesis and physico-chemical properties of hyaluronic acid nanoparticles. Particles were crosslinked with adipic hydrazide and chloride carbodiimide under controlled conditions. The nanoparticles obtained with all three studied solvents were moderately electrostatically stable. Experiments with acetone produced the smallest particle size (120.44 nm) and polydispersity (0.27). The size and polydispersity of hyaluronic acid nanoparticles correlated with the surface tension between water and the organic solvents, not with the thermodynamic affinity of water for the organic solvents.  相似文献   
128.
A strain of Pseudomonas causing blue discoloration was isolated from processed cheese ‘Requeijão em Barra’ and studied by whole-genome sequencing. The strain RQ057 was identified as Pseudomonas paracarnis using the TYGS web server and also by in silico DNA–DNA hybridisation and ANIb calculation. Pyoverdine biosynthetic clusters, integrative and conjugative elements (ICE), prophage regions and genomic islands (GIs) were predicted. Furthermore, we observed that copies of genes related to the tryptophan biosynthetic pathway (trpCBAFD), which are exclusive to strains causing blue discoloration, are contained in the region identified as ICE and which was also identified in GIs. This genomic region also contains genes for transposase, type IV transport system (T4SS) and pili construction. Thereby, we can assume that this region contains potential conjugative-transposon-like mobile genetic elements and it has plasmid-like conjugative properties.  相似文献   
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