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51.
Adsorption kinetic of molasses wastewaters after anaerobic digestion (MSWD) and melanoidin respectively on activated carbon was studied at different pH. The kinetic parameters could be determined using classical kinetic equations and a recently published fractal kinetic equation. A linear form of this equation can also be used to fit adsorption data. Even with lower correlation coefficients the fractal kinetic equation gives lower normalized standard deviation values than the pseudo-second order model generally used to fit adsorption kinetic data, indicating that the fractal kinetic model is much more accurate for describing the kinetic adsorption data than the pseudo-second order kinetic model.  相似文献   
52.
Female infertility has a multifactorial origin, and exposure to contaminants, including pesticides, with endocrine-disrupting properties is considered to be involved in this reproductive disorder, especially when it occurs during early life. Pesticides are present in various facets of the environment, and consumers are exposed to a combination of multiple pesticide residues through food intake. The consequences of such exposure with respect to female fertility are not well known. Therefore, we aimed to assess the impact of pre- and postnatal dietary exposure to a pesticide mixture on folliculogenesis, a crucial process in female reproduction. Mice were exposed to the acceptable daily intake levels of six pesticides in a mixture (boscalid, captan, chlorpyrifos, thiacloprid, thiophanate and ziram) from foetal development until 8 weeks old. Female offspring presented with decreased body weight at weaning, which was maintained at 8 weeks old. This was accompanied by an abnormal ovarian ultrastructure, a drastic decrease in the number of corpora lutea and progesterone levels and an increase in ovary cell proliferation. In conclusion, this study shows that this pesticide mixture that can be commonly found in fruits in Europe, causing endocrine disruption in female mice with pre- and postnatal exposure by disturbing folliculogenesis, mainly in the luteinisation process.  相似文献   
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54.
Les 50 ha de la parcelle permanente établie par le Smithsonian Institutes (Korup Forest Dynamics Plot: KFDP) ont constitués la surface d’étude. Un total de 100 phorophytes appartenant à 5 espèces soit 20 individus par espèce choisie a fait l’objet d’échantillonnage suivant la méthode de Johansson [1]. Des échantillons récoltés indifféremment sur les autres phorophytes de cette parcelle ont permis d’avoir une idée de la flore épiphytique de ce Parc. Au total, 154 espèces dont 19 Ptéridophytes représentant 12,33 % de la flore, 10 Dicotylédones représentant 6,49 % de la flore et 125 Monocotylédones avec 81,17 % des espèces ont été récoltées. Nos investigations révèlent 9 familles et 46 genres. Les plus abondants sont les Orchidaceae (66,23 % des espèces), les Araceae (14,94 % des espèces), les Polypodiaceae (5,84 % des espèces) et les Begoniaceae (5,19 % des espèces). Au niveau genérique, Bulbophyllum est le plus abondant. Il représente 22,07 % de la flore. D’autres genres importants sont Polystachya, Culcacia et Angraecum. L’analyse canonique de la flore de ces cinq espèces supports, montre que Oubanguia alata, Cola praecuta et Strephonema pseudocola présentent une similitude floristique. La distribution verticale des espèces indique que les niveaux II, III et IV de Johansson [1] sont les plus représentés en terme d’abondance épiphytique.

Mots clés: Flore; phorophyte; épiphyte; distribution et abondance

The study of vascular epiphytic flora of Korup National Park has been carried out in 50 hectares of the Korup Forest Dynamics Plot (KFDP). The sampling used Johansson’s method [1] of over 100 phorophytes belonging to five species of which each species is made up of 20 individuals of the same species. A collection was made through KFDP. It was noted that a total of 154 species where 19 Pteridophytes (12.33 %), 10 Dicotyledons (6.49 %) and 125 Monocotyledons (81.17 %) were thus registered. These epiphytes were divided into nine families and 46 genera. The families of greater abundance are Orchidaceae with the species of 66.23%, Araceae with the species of 14.94% and Polypodiaceae with the species of 5.84%. Other important family is Begoniaceae with the species of 5.19%. The genus Bulbophyllum is the most abundant; it is represented by the species of 22.07%. The analysis of flora, thanks to the statistical test, shows that Oubanguia alata, Cola praecuta and Strephonema pseudocola are floristically the same. The vertical distribution shows that, the II, III and IV levels of Johansson [1] are those mostly represented.  相似文献   
55.
A novel built-in voltage sensor circuit has been developed in 90-nm CMOS technology to characterize temporal and physical locations of ion hits. The sensing circuit only has 8 transistors, with very small area and power overhead. Simulations and laser experimental results illustrate the effectiveness of the sensing circuit. The sensors can be implemented in grid formation to systematically detect the ion hits in real time.  相似文献   
56.
The aims of this study were to identify differences in the centre of buoyancy (CB) and centre of mass (CM) locations of male and female collegiate swimmers, and to assess the influence that buoyancy has on freestyle kicking performance. Sixteen female collegiate swimmers (mean +/- s: age 19.1 +/- 1.2 years) had significantly more adipose tissue (20.2 +/- 4.4%) than 15 male collegiate swimmers (19.9 +/- 1.0 years, 12.6 +/- 3.8%). The ratio of the sum of abdominal and suprailiac skinfolds to the thigh skinfold was significantly greater for the males (2.07 +/- 0.37) than the females (1.31 +/- 0.32), implying that females had proportionately more fatty tissue caudally than males. The distance d between the centres of buoyancy and mass was significantly larger for the males (0.79 +/- 0.43 cm) than the females (0.16 +/- 0.34 cm). Both points were more caudal in the female subjects (59.9 +/- 0.7% and 59.8 +/- 0.7% of body height respectively) than in the male subjects (61.7 +/- 0.8% and 61.2 +/- 0.9% respectively). These data suggest that the difference in d may be attributed to the difference in the location of the centre of buoyancy, because the centre of mass difference was not significant and was characterized by a smaller effect size. The amount and distribution of adipose tissue accounted for a significant proportion of variance in d (R2 = 0.25 and 0.29 respectively). Males had a significantly higher proportional kick time, defined as the ratio of times to complete a 22.9 m sprint when kicking and swimming respectively, than females (1.57 +/- 0.09 and 1.51 +/- 0.13 respectively). This shows that the male swimmers kicked proportionally more slowly than the female swimmers. However, the distance d did not account for a significant proportion of variance in the proportional kick time. Therefore, our results do not support the notion that skilled male swimmers are at a performance disadvantage in terms of natural buoyancy characteristics.  相似文献   
57.
Martin  U.  Fuhl  J.  Gaspard  I.  Haardt  M.  Kuchar  A.  Math  C.  Molisch  A.F.  Thomä  R. 《Wireless Personal Communications》1999,11(1):109-129
Intelligent antennas offer the possibility of greatly increasing the capacity of cellular mobile radio systems. We give a comprehensive overview of the literature concerning model scenarios for applications of direction-selective intelligent antennas. Measurement campaigns and simplified models are described that have been derived from these measurements or from physical considerations. Furthermore, directional fading simulators are reviewed which are essential for testing of smart antenna systems.  相似文献   
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59.
Non-structural parameters such as surface distresses and ride quality have commonly been used as functional indicators in the treatment selection process. However, transportation agencies have considered in recent years implementing structural capacity indicators into their pavement management system (PMS) and decision-making processes. The objective of this study was to develop a structural condition index for Louisiana, known as the Structural Health Index (SHI), on a scale from 0 to 100 that describes the structural integrity of the pavement structure based on the backcalculated layer moduli of in-service pavements as predicted from FWD testing. Based on the developed methodology, the SHI is estimated by first backcalculating the layer moduli using a backcalculation software. Then, a sigmodal function is used to calculate the SHI. Evaluation and validation of the SHI was successful and demonstrated that the new index responded realistically to sections in poor and in good structural conditions. Furthermore, it was shown that the new index provided additional information that complements existing functional indices in PMS by successfully identifying structurally deficient sections. The implementation of the SHI into the LADOTD decision matrix is demonstrated.  相似文献   
60.
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