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81.
The role of lipid oxidation and humidity absorption on the shelf life of biscuits was analysed. Biscuits with low lipid and sugar content were prepared employing different oils, and texture changes that biscuits experience during storage were studied. Water activity, peroxide value, malonaldehyde content and colour were also determined at different storage times. The maximum peroxide level was between 1 and 1.5 mmol kg?1 of oil, at 166 days of storage. Values of malonaldehyde were between 5.2 and 15.8 nmol g?1 of dry sample. Water activity and peroxide value influence the biscuit texture (P ≤ 0.05). To study the effects of both factors simultaneously, a mathematical model was adjusted to the data. Results indicate that an increase in the peroxide level, even at low level of lipid oxidation, increases Young's modulus and leads to a harder biscuit, while the humidity absorption lowers the fracture stress and Young's modulus.  相似文献   
82.
BACKGROUND: In the last few years, agricultural uses of waste waters from olive processing‐related industries have been gaining interest mainly with a view to composting or bio‐fertilizers. The present work examines physico‐chemical, toxicological and geno‐toxicological properties of three liquid wastes, namely olive mill wastewater (OMWW), olive wet husk and olive brine. The effect of OMWW spreading on soil microbial activity and biomass was also evaluated. RESULTS: Data from Artemia salina and Lactuca sativa toxicity tests indicated high levels of lethality, and inhibitory effects on seed germination and seedling growth of all olive wastes. The genotoxicity assays using Allium cepa tests showed contrasting results. At high concentrations, olive wastes caused inhibition or suppression of mitosis. However, they did not produce induced anaphase aberrations. Data on reversion of Salmonella thyphimurium strains using the Ames test indicated that the olive wastes did not present mutagenic activity. Results from the field experiment showed that OMWW at a 500 m3 ha?1 had the highest values of both soil microbial activity and biomass after 3 months of the amendment application. CONCLUSION: This work adds new data for environmental risk assessment of olive industrial wastes. Direct use of olive wastes for agricultural purposes should be limited owing to their possible chemotoxic, phytotoxic and antimicrobial effects. Copyright © 2011 Society of Chemical Industry  相似文献   
83.
The influence of damaged starch content on particle size distribution and rheological properties of unheated starch suspensions and pasting properties were investigated. Four samples containing different amounts of damaged starch were studied. Particle size distribution curves shifted toward higher diameters, and a greater overlap of both populations of particles (A- and B-type granules) and a decrease of both peak heights were produced. The flow curves of unheated starch suspensions were fitted using the power law model. The flow behavior indexes were higher than the unit. The consistency coefficient increased with the increment of damaged starch content. Unheated starch suspensions showed time-dependent rheological behavior and were described by the Weltman model. The unheated suspensions exhibited a thixotropic behavior. With regard to the pasting process, the increment of damaged starch content produced gradual reductions in peak viscosity, final paste viscosity, breakdown and setback. Results demonstrated the importance of the presence of physically damaged granules in wheat starch rheological characteristics.  相似文献   
84.
Fetal bovine serum (FBS) is an important factor in the culture of Trypanosoma cruzi, since this parasite obtains and metabolizes fatty acids (FAs) from the culture medium, and changes in FBS concentration reduce the degree of unsaturation of FAs in phosphoinositides. When T. cruzi epimastigotes were cultured with 5% instead of 10% FBS, and stearic acid was used as the substrate, ∆9 desaturase activity decreased by 50%. Apparent K m and V m values for stearic acid, determined from Lineaweaver–Burk plots, were 2 μM and 219 pmol/min/mg of protein, respectively. In studies of the requirement for reduced pyridine nucleotide, ∆9 desaturase activity reached a maximum with 8 μM NADH and then remained constant; the apparent K m and V m were 4.3 μM and 46.8 pmol/min/mg of protein, respectively. The effect of FBS was observed only for ∆9 desaturase activity; ∆12 desaturase activity was not affected. The results suggest that decreased FBS in culture medium is a signal that modulates ∆9 desaturase activity in T. cruzi epimastigotes.  相似文献   
85.
The objective of this transversal study was to determine folate and iron nutritional status of women in fertile age from Municipio Jiménez, Lara State, Venezuela. The sampling was probabilistic by conglomerates from the urban and rural areas, selecting 15 conglomerates from which women between 12 and 45 years (269), were studied. After signing informed consent, participating were interviewed for personal data, antecedents related to folate and iron, socioeconomic data (Graffar-Mendez Castellano method and unsatisfied basic needs). In blood sample was determined Hemoglobin, and Erythrocytic Folate (FE). Serum was obtained to determine Ferritin and Serum Folate (FS). 53.53% of the sample presented low FS levels, 10.78% were FS deficient. Severe FE deficiency was present in 80.7% of the cases, moderate deficiency affected 5.9%. For both tests, median was higher for women in treatment with Acido Fólico or pregnant (p = 0.000), median for FE was higher for adults (p = 0.001) and in non poor women (p = 0.011). There were no significant differences for coffee, alcohol, anticonceptive consumption, urban or rural resident or socioeconomic strata. The prevalence of anemia was 11.2% being significantly more frequent in adults than in adolescents (p = 0.029) and in urban women (p = 0.042). Low ferritin were found in 37.3% of the sample, the effect of different variables was not statistically significant. In conclusion, there is a high prevalence of iron and folate deficiencies in women of fertile age from Municipio Jiménez, which could constitute a conditioning factor for the appearance of neural tube defects.  相似文献   
86.
Significant effort has been directed in recent times to the use of plants to extract and detoxify nitroaromatics from polluted industrial facilities. We have explored the possibility of overcoming the phytotoxicity of the highly toxic and recalcitrant nitroderivative 2,4-dinitrotoluene (2,4-DNT) by expressing a cyanobacterial flavodoxin (Fld) in tobacco plants. We demonstrate here that transformants accumulating Fld in plastids display a remarkable increase in the ability to tolerate, take up, and transform 2,4-DNT, as compared to their wild-type siblings. We also show that Fld mediates one-electron reduction of 2,4-DNT in the presence of oxygen and especially in anaerobiosis. Moreover, Fld-loaded chloroplasts are able to convert 2,4-DNT into its aminoderivatives in the presence of light. The results suggest that expression of Fld in landscape plants could facilitate effective cleanup of sites contaminated with this class of pollutants.  相似文献   
87.
Sorghum is an underutilized cereal in human food production, despite its flour being a potential gluten‐free (GF) source in the development of several foods. Thus, the aim of the present investigation was to evaluate the effects and interactions of different ingredients on cooking quality and texture of GF pasta. Egg albumen (A), egg powder (E), xanthan gum (X), and pregelatinized corn starch (P) were used as ingredients, and Box‐Behnken experimental design was applied to study the effects of these ingredients on pasta cooking behavior, color, and texture attributes. Responses were fitted to a second order polynomial equation, and multivariable optimization was performed using maximization of general desirability. Next, optimal formulations were validated, compared with two commercial gluten‐free pastas by sensory evaluation, and finally, an industrial assay was carried out. Regression coefficients indicated that A and P improved cooking properties while A and E contributed the most to improving the pasta textural properties. As, X and P effects varied depending on the kind of sorghum flour used, the optimal formulations levels were different, but in both cases these models were satisfactory and capable of predicting responses. The industrial assay was carried out with white sorghum flour because it showed a higher acceptability in the sensory evaluation than brown sorghum flour pasta. This industrially made pasta resulted in slightly better cooking properties than the laboratory produced one, with the formulation adapting well to the conventional wheat pasta industrial process. Gluten‐free sorghum pasta was produced, showing good cooking and textural properties and being a suitable option for gluten‐sensitive individuals.  相似文献   
88.
The anti-inflammatory role of regulatory B cells (Breg cells) has been associated with IL-35 based on studies of experimental autoimmune uveitis and encephalitis. The role of Breg cells and IL-35+ Breg cells for type 1 diabetes (T1D) remains to be investigated. We studied PBMCs from T1D subjects and healthy controls (HC) and found lowered proportions of Breg cells and IL-35+ Breg cells in T1D. To elucidate the role of Breg cells, the lymphoid organs of two mouse models of T1D were examined. Lower proportions of Breg cells and IL-35+ Breg cells were found in the animal models of T1D compared with control mice. In addition, the systemic administration of recombinant mouse IL-35 prevented hyperglycemia after multiple low dose streptozotocin (MLDSTZ) injections and increased the proportions of Breg cells and IL-35+ Breg cells. A higher proportion of IFN-γ+ cells among Breg cells were found in the PBMCs of the T1D subjects. In the MLDSTZ mice, IL-35 administration decreased the proportions of IFN-γ+ cells among the Breg cells. Our data illustrate that Breg cells may play an important role in the development of T1D and that IL-35 treatment prevents the development of hyperglycemia by maintaining the phenotype of the Breg cells under an experimental T1D condition.  相似文献   
89.
This paper addresses the development of a random forest classifier for the multi-class fault diagnosis in spur gearboxes. The vibration signal’s condition parameters are first extracted by applying the wavelet packet decomposition with multiple mother wavelets, and the coefficients’ energy content for terminal nodes is used as the input feature for the classification problem. Then, a study through the parameters’ space to find the best values for the number of trees and the number of random features is performed. In this way, the best set of mother wavelets for the application is identified and the best features are selected through the internal ranking of the random forest classifier. The results show that the proposed method reached 98.68% in classification accuracy, and high efficiency and robustness in the models.  相似文献   
90.
Glucosinolate transporters (GTRs) are part of the nitrate/peptide transporter (NPF) family, members of which also transport specialized secondary metabolites as substrates. Glucosinolates are defense compounds derived from amino acids. We selected 4-methylthiobutyl (4MTB) and indol-3-ylmethyl (I3M) glucosinolates to study how GTR1 from Arabidopsis thaliana transports these substrates in computational simulation approaches. The designed pipeline reported here includes massive docking of 4MTB and I3M in an ensemble of GTR1 conformations (in both inward and outward conformations) extracted from molecular dynamics simulations, followed by clustered and substrate–protein interactions profiling. The identified key residues were mutated, and their role in substrate transport was tested. We were able to identify key residues that integrate a major binding site of these substrates, which is critical for transport activity. In silico approaches employed here represent a breakthrough in the plant transportomics field, as the identification of key residues usually takes a long time if performed from a purely wet-lab experimental perspective. The inclusion of structural bioinformatics in the analyses of plant transporters significantly speeds up the knowledge-gaining process and optimizes valuable time and resources.  相似文献   
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