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71.
Multimedia Tools and Applications - A large range of new applications are appearing nowadays on the Web in which content and data produced by single users or groups are going to be adapted,...  相似文献   
72.
In many health care situations, powerful mobile tools may help to make decisions and provide support for continuous education and training. They can be useful in emergency conditions and for the supervised application of protocols and procedures. To this end, content models and formats with semantic and intelligence have more flexibility to provide medical personnel (both in off-line and on-line conditions) with more powerful tools than those currently on the market. In this paper, we are presenting Mobile Medicine solution, which exploits a collection of semantic computing technologies together with intelligent content model and tools to provide innovative services for medical personnel. Most of the activities of semantic computing are performed on the back office on a cloud computing architecture for: clustering, recommendations, intelligent content production and adaptation. The mobile devices have been endowed with a content organizer to collect local data, provide local suggestions, while supporting taxonomical searches and local queries on PDA and iPhone. The proposed solution is under usage at the main hospital in Florence. The smart content has been produced by medical personnel, with the adoption of the new ADF-Design authoring tool, which produces content in MPEG-21 format. The mobile content distribution service is integrated with a collaborative networking portal, for discussion on procedures and content, thus suggestions are provided on both PC and Mobiles (PDA and iPhone).  相似文献   
73.
The effects of selected variables, i.e. temperature, water activity and yeast inoculation level, on the lipolytic pattern and volatile production by Yarrowia lipolytica Y16A (chosen on the basis of a previous screening) were assessed. The variables were varied according to a central composite design and the models obtained enabled evaluation and weighting of the effects of the independent variables on the free fatty acids (FFAs) and volatile profiles in pork fat based medium. The polynomial models showed the levels temperature, water activity of the pork fat based system and yeast strain inoculation were able to maximize the release of specific FFAs or molecules of sensory importance.  相似文献   
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75.
The aim of this work was to evaluate, using the response surface methodology, the effects of different levels of high-pressure homogenization (HPH) on the microbiological and rheological characteristics of yoghurts having different contents of fat and milk solids. The HPH treatment of milk resulted a useful tool to obtain yoghurts having a greater variety of textures associated to a high microbiological quality. In fact, all the yoghurt types obtained by using milk treated with different levels of pressure were characterized by cell loads of the starter cultures higher than 8 log10 cfu ml−1 immediately after the fermentation and than 7 log10 cfu ml−1 after 60 days of storage at 4°C. The HPH treatment seems to favor the growth of Streptococcus thermophilus with respect to that of Lactobacillus delbrueckii subsp. bulgaricus, regardless of the level of pressure applied. The use of a Central Composite Design (CCD) and the polynomial models obtained permitted to individuate the levels of the three independent variables (pressure level, milk solids and fat concentration) able to maximize the growth of starters during the fermentation process, to minimize their viability loss during the refrigerated storage as well as to define their effects on the product viscosity.  相似文献   
76.
The interaction between tyrosine-decarboxylase and proteolytic activities of a Lactobacillus curvatus and Staphylococcus xylosus, respectively, on biogenic amine production during the ripening and the storage of dry fermented sausages was investigated. Water content, pH, proteolysis parameters, microbial counts, and biogenic amine contents were monitored in spontaneously and starter fermented sausages. The use of proteolytic staphylococci as starter resulted in a higher content of non-protein nitrogen and total free amino acids. Tyramine was the main amine produced in all batches. However, tyrosine-decarboxylase activity of the L. curvatus starter strain was weak and yielded lower amounts of tyramine than those produced by the wild mioroflora in the control batch. Association between tyramine production and proteolysis could only be established in a defectively dried batch. Putrescine and cadaverine accumulation was efficiently reduced in the starter-mediated fermentation, in agreement with the lower development of enterobacteria. Phenylethylamine and tryptamine were only detected in the spontaneously fermented sausages, while histamine, spermine and spermidine did not vary during the ripening. Biogenic amine levels and related parameters showed significant changes during the storage of dry sausages depending on the temperature and the batch. As a general rule, changes in the pH, proteolysis, microbial counts, and biogenic amine contents were stronger at 19 degrees C than at 4 degrees C. The results suggest that refrigeration would be advisable for preventing further accumulation of biogenic amines during the storage of dry fermented sausages.  相似文献   
77.
Introducing a variable cosmological function Λ(t) in a geometrical manner from a 5D Riemann-flat metric, we investigate the possibility of having a geometric criterion to choose a suitable cosmological function Λ(t) for every 4D dynamical hypersurface capable of generating phantom cosmologies.  相似文献   
78.
The individual and interactive effects of temperature, pH and NaCl on the aminopeptidase-types N and A and proline iminopeptidase activities of several strains of non-starter lactic acid bacteria (NSLAB) were studied by quadratic response surface methodology. The effects on enzyme activities depended on the interactions among the independent variables, species, strains within species and type of activity. With few exceptions, the aminopeptidases N and A and proline iminopeptidase activities of Lactobacillus casei ssp. pseudoplantarum and Lb. curvatus were strongly inhibited by the hostile cheese-like conditions, while the peptidases of Lb. casei ssp. casei and especially Lb. plantarum were tolerant or not affected by variations in pH and showed the least sensitivity to NaCl or even a requirement for NaCl for the optimal activity. Strains which maintained relatively high activity under cheese-like conditions were selected within the species. The proline iminopeptidase of Lb. casei ssp. casei 2107 as well as Lb. plantarum 2788 and 2789 greatly tolerated the interactions among the independent variables. At 10°C in the presence of 3.750% NaCl and independent of the pH, the PepN activity of Lb. plantarum 2788 and 2789 was at least 33% of the maximum determined at pH 7.5 and 35°C. Proline iminopeptidase activity was most sensitive to the individual and interactive variations in temperature, pH and NaCl. On the other hand, aminopeptidase-type A activity seemed to be least sensitive to cheese-like conditions.  相似文献   
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80.
Despite the absence of cardiac or renal pathologies, edema and mild hyponatremia may often occur in patients affected by chronic obstructive pulmonary disease (COPD). Therefore, it has been suggested that hypoxia may influence the release of different hormones regulating renal sodium handling. To evaluate the effect of hyperoxia and O2 removal on plasma digitalis-like substance (DLS) levels, 9 patients affected by COPD and 7 normal subjects were studied. After 1 h in supine position, O2 was administered for 3 h by a tight-fitting face-mask. Blood samples for plasma DLS were taken at time 0, 60, 180 min and then for 3 h after O2 removal. In normal subjects, plasma DLS did not vary after O2 administration (from basal values of 162.25 +/- 8.59 to 107.75 +/- 6.65 pg/ml at 180 min; NS), and O2 removal (143.7 +/- 16.87 pg/ml after 3 h from O2 removal; NS). On the contrary, in patients affected by COPD, plasma DLS levels increased during O2 administration (from basal values of 138.98 +/- 8.31 to 202.14 +/- 8.21 pg/ml at 180 min; p < 0.05), and returned to baseline levels (142.59 +/- 8.28 pg/ml) 3 h after O2 removal. In the same patients, DLS increase was accompanied by a rise in Na+ excretion (from 0.08 +/- 0.01 at time 0 to 0.16 +/- 0.02 mEq/min after 3 h of O2 administration; p < 0.05). In conclusion, our findings showed an oxygen-related increase in plasma DLS levels and in urinary Na+ excretion in patients affected by COPD. This phenomenon could promote Na+ urinary loss during prolonged O2 therapy in these patients and should be taken into account in their management.  相似文献   
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