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741.
Marialice Pinto Coelho Silvestre Harriman Aley Morais Mauro Ramalho Silva Mariana Wanessa Santana de Souza Viviane Dias Medeiros Silva 《International Journal of Food Science & Technology》2012,47(7):1532-1539
The action of proteases from Bacillus licheniformis and Aspergillus oryzae was studied with the aim of preparing hydrolysates from whey protein concentrate with nutritionally appropriate peptide profile. Various enzyme/substrate ratios were used, and the peptides were fractionated by size‐exclusion HPLC followed by their quantification using the rapid method of correct fraction area (CFA). The protease from B. licheniformis (E:S of 8:100) produced the best peptide with a much lower amount of large peptides (44.61%), greater of di‐ and tripeptides (8.79%) and higher sum of the di‐ and tripeptides with free amino acids (9.99%) than the other hydrolysates. The advantage of using a lower E:S ratio to obtain a nutritionally adequate peptide profile was observed for the protease of A. oryzae when it passed from 3:100 to 2:100. 相似文献
742.
Often, when we scan a document, the image from the back page shows through, due to partial transparency of the paper, giving rise to a mixture of two images. We address the problem of separating these images through the use of a physical model of the mixture process. The model is nonlinear but invertible, and we use the inverse model to perform the separation. The model is trained through the MISEP technique of nonlinear ICA. Bounded independent sources are proved to be separable through this method, apart from offset, scale and permutation indeterminacies.We compare our results with those obtained with other approaches and with different separation models that were trained with MISEP. For the latter case we test a bilinear model and MLP-based models, using both symmetry-based regularization and the more recently proposed minimal nonlinear distortion regularization. Quantitative quality measures show that the approach that we propose is superior to the other methodologies. 相似文献
743.
Ion Anghel Carmen Limban Alexandru Mihai Grumezescu Alina Georgiana Anghel Coralia Bleotu Mariana Carmen Chifiriuc 《Nanoscale research letters》2012,7(1):513
In this paper, we report the design of a new nanofluid for anti-pathogenic surface coating. For this purpose, new 2-((4-ethylphenoxy)methyl)-N-(substituted-phenylcarbamothioyl)-benzamides were synthesized and used as an adsorption shell for Fe3O4/C12 core/shell nanosized material. The functionalized specimens were tested by in vitro assays for their anti-biofilm properties and biocompatibility. The optimized catheter sections showed an improved resistance to Staphylococcus aureus ATCC 25923 and Pseudomonas aeruginosa ATCC 27853 in vitro biofilm development, as demonstrated by the viable cell counts of biofilm-embedded bacterial cells and by scanning electron microscopy examination of the colonized surfaces. The nanofluid proved to be not cytotoxic and did not influence the eukaryotic cell cycle. These results could be of a great interest for the biomedical field, opening new directions for the design of film-coated surfaces with improved anti-biofilm properties. 相似文献
744.
Bentosela Mariana; Jakovcevic Adriana; Elgier Angel M.; Mustaca Alba E.; Papini Mauricio R. 《Canadian Metallurgical Quarterly》2009,123(2):125
Dogs (Canis familiaris) trained to receive a preferred food (dry beef liver) from an experimenter learned to maintain a longer gaze on the experimenter than dogs receiving a less preferred food (dog pellets). Dogs downshifted from dry liver to pellets rejected food more frequently than nonshifted controls. Gaze duration also decreased in downshifted dogs below the level of a group always reinforced with pellets. In addition, downshifted dogs tended to move away from the experimenter, adopting a lying down posture. This phenomenon, called successive negative contrast, has been described in analogous experiments with a variety of mammalian species, but has failed to occur in similar experiments with nonmammalian vertebrates. Unlike similar previous observations, the present data were obtained in an environment involving interspecific communication. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
745.
746.
Cabizuca Mariana; Marques-Portella Carla; Mendlowicz Mauro V.; Coutinho Evandro S. F.; Figueira Ivan 《Canadian Metallurgical Quarterly》2009,28(3):379
Objective: To estimate PTSD prevalence in parents of children with chronic illnesses or undergoing invasive procedures, and its association with higher risk of PTSD among parents. Methods: Sixteen studies reporting prevalence of PTSD in parents of children with chronic illnesses were identified through a systematic review in Pubmed, Web of Science, Pilots and PsycINFO databases. Main Outcome Measures: Pooled current PTSD prevalence was calculated for parents from these studies. Pooled PTSD prevalence ratios were obtained by comparing parents of children with chronic diseases with parents of healthy children. Meta-regression was used to identify variables that could account for the lack of homogeneity. Results: Pooled PTSD prevalence was 19.6% in mothers, 11.6% in fathers, and 22.8% in parents in general (p 相似文献
747.
An analytical solution for the transient two-dimensional atmospheric pollutant dispersion problem is presented. The approach used in this problem utilizes the double GITT (Generalized Integral Transform Technique), the Laplace Transform and the matrix diagonalization. Furthermore, mathematical filters are used due to the existence of non-homogeneous boundary conditions. The results we obtained are compared with experimental data for short range downwind dispersion utilizing two well-known experimental dispersion datasets (Copenhagen and Prairie Grass). It is shown that the present analytical approach give good results for downwind concentration except for receptors very close to the release points were any Eulerian approach based on K-closure is known to fail. 相似文献
748.
We study and develop constraint preserving boundary conditions for the Newtonian magnetohydrodynamic equations and analyze the behavior of the numerical solution upon considering different possible options. We concentrate on both the standard ideal MHD system and the one augmented by a “pseudo potential” to control the divergence free constraint. We show how the boundary conditions developed significantly reduce the violations generated at the boundaries at the numerical level and how lessen their influence in the interior of the computational domain by making use of the available freedom in the equations. 相似文献
749.
Virginia VANASCO Timoteo MARCHINI Natalia MAGNANI Tamara VICO Mariana GARCES Lourdes CACERES Alejandro GUAGLIANONE Pablo EVELSON Silvia ALVAREZ. 《Biocell》2016,40(1):47-50
Several authors have addressed the importance of mitochondrial function in inflammatory syndromes, as it may play a role in the genesis of tissue injury. Sepsis and exposition to environmental particles are
examples of inflammatory conditions. Sepsis occurs with an exacerbated inflammatory response that damages
tissue mitochondria and impairs bioenergetic processes. One of the current hypotheses for the molecular mechanisms underlying the complex condition of sepsis is that enhanced NO production and oxidative stress lead to
mitochondrial dysfunction, bioenergetic derangement and organ failure. The mechanism of particulate matter-health effects are believed to involve inflammation and oxidative stress. Components in particles that elicit
inflammation have been poorly investigated, although recent research points out to the contribution of compositional elements and particle size. Oxygen metabolism and mitochondrial function appear to be important areas
of study in inflammatory conditions for clarifying molecular mechanisms involved. 相似文献
750.