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91.
92.
In this study the combinatorial action of the main phenolic acids (ferulic, caffeic, p-coumaric and sinapic acids) found in extracts of free (ME) and bound phenolic acids (HE) from oat, barley and wheat flour on the modulation of NF-κB activity was investigated. The results show that combination of phenolic acids in low concentrations (<0.1 μg/ml) has a significant synergistic, or enhanced effect, on NF-κB activity, while their combination in high concentrations (0.3–70 μg/ml) helps to suppress the strong effect obtained by individual solutions of ferulic and p-coumaric acids. The modulation of NF-κB activity observed by HE extracts is the effect of combinatorial action of the phenolic acids present therein, while the modulation of NF-κB activity observed with ME extracts is the result of combinatorial action of phenolic acids together with other phenolic compounds present in the extracts. These results increase the knowledge about the health promoting effect from cereal consumption and dietary phenolic acids.  相似文献   
93.
Sorption behavior of nonylphenol in terrestrial soils   总被引:1,自引:0,他引:1  
Nonylphenol (NP) as an intermediate from anaerobic degradation of widely used nonionic surfactants occurs widespread in the environment. Partition behavior of this toxic and endocrine-disrupting chemical between soil and water was not examined until yet. The objective of this investigation was to quantify sorption and desorption behavior of 4-nonyl[14C]phenol in a set of 51 soils using the batch equilibrium approach. Kinetic studies indicated apparent equilibrium within 20 h. Sorption was influenced by sorbate structure as could be shown with branched 4-nonyl[14C]phenol and the linear 4-n-NP, respectively. Linear 4-n-NP behaves differently from the branched isomers of 4-NP. Sorption of 4-nonyl[14C]phenol tested with five different initial concentrations resulted in linearly fitted isotherms that provided calculation of sorption partition coefficients (KP). Desorption partition coefficients (KP-des) revealed hysteresis independent of soil properties but decreasing with decreasing initial NP concentrations. KP values were correlated with organic carbon content of the soils yielding a log KOC of 3.97.  相似文献   
94.
Incorporation of wheat bran has a significant effect on the texture of extruded starchy products. This can be explained by changes in the mechanical parameters of the products. The stress at rupture and elastic modulus of wheat flour-based solid foams, obtained at different extrusion conditions and bran concentration, were measured using a three-point bending test. Both parameters were positively correlated with the foam relative density according to the Gibson–Ashby model. At same relative densities and bran concentration, finer structures with higher density of small cells led to a higher mechanical strength of the foams. The stress at rupture of the unexpanded material was decreased when increasing the bran concentration. Nevertheless, expanded foams with added bran at an intermediate level showed increased mechanical strength. This was attributed to the finer cellular structures obtained. The effect of increasing the bran to a higher concentration on the mechanical properties was depending on the cell wall thickness and bran particle dimensions. At high relative density, the strength of the foams was further increased due to the even finer structures obtained. At low relative density, even though finer structures were also obtained, the stress at rupture of the foams was decreased. This may be explained by the lower cell wall thicknesses and low adhesion properties between bran and starch favoring rupture of the cell walls.  相似文献   
95.
In the past flavor research and the development of new flavorings were constantly driven by the interaction of flavor analysis, structure elucidation, and chemical synthesis accompanied by sensory. Highly potent flavor compounds were identified in numerous food products and helped to establish a powerful toolbox for flavorists. Nowadays we experience the merging of various scientific disciplines, for example medicine, biology, chemistry, and various technologies in the field of flavor research, which shows direct impact on our understanding of flavors. At the same time modern life has profoundly changed our eating habits. This situation generates new challenges for product development teams, which represent all facets of technologies. This paper will illustrate different examples for the evolution of product-oriented flavor research and future trends.  相似文献   
96.
Oranges are clinically relevant allergenic foods. To date, orange allergens have not been characterized in detail. The study is aimed at analyzing the sensitization profile in orange-sensitized subjects with and without clinical allergy, and to identify orange allergens. Fifty-six sensitized subjects with self-reported reactions to orange were grouped into reactors (anaphylaxis or multiple episodes of immediate reactions and/or positive challenge tests) and non-reactors (negative open food challenge tests). Allergens were characterized by IgE immunoblotting, N-terminal sequencing, IgE-inhibition assays, and mediator release assays were performed to determine the allergenic potency of orange profilin. Of 56 subjects, 23 were classified as orange allergic showing mainly an oral allergy syndrome. Of 23 subjects classified as orange allergic, 22 were sensitized to profilin, Cit s 2. In patients with mono-sensitization to profilin in vitro histamine releases up to 75% from basophils were induced using orange extract and purified plant profilins. Of the allergic patients 78% were sensitized to germin-like protein, Cit s 1. Both allergens showed retained IgE reactivity in heat-processed orange juice. Interestingly, subjects with and without clinical allergy showed a comparable sensitization profile. Profilin and germin-like proteins are major orange allergens. The potential clinical relevance of orange profilin was indicated by its strong capacity to release histamine from basophils. However, a predominant sensitization to both allergens in subjects without symptoms also indicates a high frequency of clinically insignificant sensitization.  相似文献   
97.
Roasting trials with a modified coffee roaster revealed that the attained end‐temperature is the key parameter for control of non‐enzymatic browning during malt production. The development of the main Maillard reaction related malt characteristics (colour, antioxidative activity and flavour) was therefore assessed under mild, intermediate and intensive roasting conditions with end‐temperatures of 120, 150 and 180°C, respectively. Since maximal browning occurred between 125 and 160°C, the rate of colour formation during mild roasting significantly differed from the other two conditions (3.5 versus 15 European Brewery Convention (EBC) units/min). High molecular weight (HMW) mela‐noidins (> 70 kDa) were mainly generated by intensive roasting (between 157 and 166°C). The sudden formation of HMW mela‐noidins coincided with the abrupt decrease of the level of vicinal diketones and radical scavenging antioxidants, indicating a possible role for these compounds in the polymerisation reactions that lead to the formation of HMW melanoidins.  相似文献   
98.
Wheat bran is multi-layered and consists of different cell types with different chemical compositions. The relatively high content of protein as well as the small amount of lignin is the key differentiator to other lignocellulose containing biomasses. Following the classical route of a biorefinery, bran may be disintegrated to a high extent and separated into fractions of high purity in order to build up new chemicals which serve as precursors for higher polymerized compounds. Secondly, bran contains substances that are per se valuables, but need to be further separated and purified.  相似文献   
99.
Wheat, together with maize and rice, accounts to about 90% of the world's cereal production. During the milling process, wheat bran, besides other valuable compounds such as wheat germ and parts of the endosperm, remains as major by-product. Wheat bran is composed of various histological cell layers, called the pericarp, testa, hyaline and aleurone layer and its weight ratio to milled wheat is about 25%. Annually, over 650 million tons of wheat are produced in the world, of which more than 69% are used for food. The thereby accruing biomass of wheat bran can be estimated as 150 million tons, which are basically used in the feed industry. Even if numerous studies have investigated potential health benefits of consuming more whole grain foods, the addition of bran to existing food systems may confer difficulties in terms of processing, nutrition or sensory acceptance by consumers. This review will summarize state-of-the-art technological approaches such as mechanical, thermal or enzymatic treatment used to modify the functional properties of wheat bran and coincidently describe the impact on the food system.  相似文献   
100.
In the present study, we have analyzed muscle, liver, and adipose tissue of 33 red foxes from Belgium for their content of polybrominated diphenyl ethers (PBDEs). Median sums of seven tri- to hepta-BDEs (BDE 28, BDE 47, BDE 99, BDE 100, BDE 153, BDE 154, and BDE 183) were 2.2, 2.4, and 3.4 ng/g lipid weight in adipose tissue, liver, and muscle, respectively. These levels were lower than those found in various species of voles and mice, the main prey species of the red fox. This is probably related to the high capacity of the foxes to metabolize and eliminate lower brominated congeners. BDE 209 generally dominated the PBDE congener profiles in the red fox samples. In samples containing BDE 209, this congener contributed, on the average, approximately 70% to the total PBDE content. BDE 209 was measured in concentrations as high as 760 ng/g lipid weight in the liver, but the detection frequency was not more than 40%. In animals with the highest BDE 209 levels, this congener was detected in muscle, liver, as well as in adipose tissue. Other abundant congeners were BDE 153 and BDE 47, which prevail in other terrestrial species. The particular PBDE congener profile observed in the red fox resembles that seen in grizzly bears from Canada, but differs from those previously reported for terrestrial avian species. Our data confirms unambiguously that BDE 209 does bioaccumulate in terrestrial top predators, such as the red fox.  相似文献   
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