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21.
In order to know which clone of acerola is better for acerola industrialization, we studied the pectin methylesterase (PME) specific activity, pectin content and vitamin C content in five different clones of acerola. The pectin yield varied from 1.37 to 2.99% and the highest content of pectin occurred in clones 3 and 5. Ascorbic acid varied significantly from 1157.5 to 1735.5 mg/100 g of pulp in the five clones. The highest content of vitamin C occurred in clone 4. The PME specific activity varied from 0.79 to 2.92 units g ?1 /g of pulp and the highest values occurred in clone 2. We also studied the optimum temperature and the optimum pH of this enzyme. Clones 1, 2, 4 and 5 showed optimum temperature at 90C. Clone 3 showed practically the same specific activity at all temperatures studied. Clones 1 and 4 showed an optimum pH of 9.0 and clone numbers 2, 3 and 5 showed a pH optimum at 8.5.  相似文献   
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The “mechanical signatures” of brittle cellular foods are known to be irregular and irreproducible. Nevertheless, their degree of jaggedness is remarkably similar and can be a measure of such foods' brittleness and perceived crunchiness/crispiness. An irregular curve's “jaggedness” is manifested by frequent direction reversals. Hence, their number can serve as a jaggedness's index. Counting the number of direction reversals in a digitized force‐displacement curve can be done with a simple algorithm, implemented in any general‐purpose software. The number of direction reversals is strongly correlated with the signature's apparent fractal dimension. It is also a reproducible enough parameter to monitor the loss of brittleness in snacks as a result of moisture sorption. This measure of jaggedness, however, is inapplicable to smooth force‐displacement curves because in such records, the small random force fluctuations produced by the digitizing process can create a false impression of “jaggedness.” Although a correction for this artifact can be introduced into the program, its utility is doubtful.  相似文献   
24.
EXTRACTION OF PROTEINS FROM BUCKWHEAT BRAN   总被引:1,自引:0,他引:1  
ABSTRACT Proteins from buckwheat bran were extracted by a wet alkaline extraction process, giving a yield of 37.0%of the total nitrogen in the liquid extract, at pH of 6.5. However, the yield could be improved, given a pretreatment of the bran with carbohydrases, thus producing a yield of 56% with cellulase, 58%with pectinase, whereas the increase was minimal with hemicellulase. The maximum yield of 67.5%was obtained by synergistic action of pectinase and hemicellulase, in a pretreatment lasting for 7 h at pH of 3.7.  相似文献   
25.
The effect of time of exposure, solution concentration and temperature on the osmotic concentration of banana (slices of 11 mm thickness) was studied in aqueous sucrose solutions. the selectivity of the cellular tissues was reduced by steam blanching the banana slices before osmotic treatment. Effective diffusion coefficients for the loss of water and the increase in sucrose content were determined according to Fick's Law applied to a two-dimensional body; calculated on the basis of the concentration of various components in the liquid phase impenetrating the fruit. These coefficients revealed values similar to binary diffusion coefficients for pure sucrose solutions.  相似文献   
26.
Graphic scaling (GS) and magnitude estimation (ME) of hedonic and intensity responses to 4–30% sucrose in lemonade and 0–16% fat in milk gave similar conclusions about the beverages, but GS was simpler to perform and responses were influenced less by numerical and contextural effects. More restricted ranges were used for ME than for GS, and for hedonic than for intensity responses. Good reproducibility was obtained, except for GS of hedonic responses to lemonade, which were bimodally distributed. Use of a higher sucrose reference (R) in lemonade decreased ME values, and increased the intensity exponent from 0.651 when R was 4% sucrose to 0.973 when R was 10% sucrose. Individual intensity exponents varied from 0.068–0.372 for milk, and from 0.146–1.075 for lemonade when R was 4% sucrose, and from 0.373–2.635 when R was 10% sucrose.  相似文献   
27.
Sugar is a determinant for the quality of mangoes, but information about its accumulation is scarce. Although starch can contribute to sugar production during ripening, not much is known about the enzymes involved. This work presents the changes in carbohydrate and enzymes during the development and ripening of Keitt mangoes. Starch disappearance was concomitant to a fivefold increase of sucrose, the most abundant sugar of the ripe fruits. The activities of α-amylase, β-amylase, phosphorylase and isoamylase were detected in the pulp, and while α-amylase increased parallel to the starch content, β-amylase presented a 20-fold increase during ripening. On the other hand, high phosphorylase activity was observed when fruits were still accumulating starch, and lowered during ripening. Isoamylase was detected during development and increased slightly during ripening, which would be in agreement to the expected role for isoamylases as acting on both subproduct of starch synthesis and degradation.

PRACTICAL APPLICATIONS


The present work reinforces our previous works that Keitt mangoes do not ripen when attached to the tree. This fact allowed us to study all the starch degradation after mango harvesting which does not occur with the other cultivars. Data obtained in this work reinforce the role of α-amylase, β-amylase and isoamylase rather than the starch phosphorylases on starch granule degradation in mangoes, and the subsequent soluble sugar accumulation.  相似文献   
28.
This research aimed to identify the drivers of acceptance and purchase intent of a probiotic (Bifidobacterium longum BL05) nonflavoured yoghurt supplemented with glucose oxidase, and to model the consumers’ acceptability using sensometrics and artificial neural networks (ANN). Consumers (n = 100) evaluated the degree of liking of yoghurt assays in respect of appearance, aroma, taste, texture and overall linking. Sensometric techniques – multiple linear regression (MLR), partial least squares regression (PLS), principal component regression (PCR) – and ANN were used to model the overall liking. Sensory drivers of global acceptance and purchase intent were also determined using logistic regression (LR). Hierarchical cluster analysis (HCA) identified three consumer segments that presented differences in all sensory attributes evaluated (P < 0.05). The ANN model showed the best performance to predict overall liking, followed by the MLR, PLS and PCR, indicating that taste and texture were the most significant attributes impacting the yoghurts overall liking. In accordance with the logistic models, overall acceptance and purchase intent could be predicted with 81.94 and 85.49% accuracy, respectively. The logistic regression indicated that taste was the attribute that contributed significantly (P < 0.0001) to higher scores for purchase intent and was considered the driver of acceptance.  相似文献   
29.
The scientific community is continuously working to translate the novel biomedical techniques into effective medical treatments. CRISPR-Cas 9 system (Clustered Regularly Interspaced Short Palindromic Repeats-9), commonly known as the “molecular scissor”, represents a recently developed biotechnology able to improve the quality and the efficacy of traditional treatments, related to several human diseases, such as chronic diseases, neurodegenerative pathologies and, interestingly, oral diseases. Of course, dental medicine has notably increased the use of biotechnologies to ensure modern and conservative approaches: in this landscape, the use of CRISPR-Cas-9 system may speed and personalize the traditional therapies, ensuring a good predictability of clinical results. The aim of this critical overview is to provide evidence on CRISPR efficacy, taking into specific account its applications in oral medicine.  相似文献   
30.
Having a formal model of neural networks can greatly help in understanding and verifying their properties, behavior, and response to external factors such as disease and medicine. In this paper, we adopt a formal model to represent neurons, some neuronal graphs, and their composition. Some specific neuronal graphs are known for having biologically relevant structures and behaviors and we call them archetypes. These archetypes are supposed to be the basis of typical instances of neuronal information processing. In this paper we study six fundamental archetypes (simple series, series with multiple outputs, parallel composition, negative loop, inhibition of a behavior, and contralateral inhibition), and we consider two ways to couple two archetypes: (i) connecting the output(s) of the first archetype to the input(s) of the second archetype and (ii) nesting the first archetype within the second one. We report and compare two key approaches to the formal modeling and verification of the proposed neuronal archetypes and some selected couplings. The first approach exploits the synchronous programming language Lustre to encode archetypes and their couplings, and to express properties concerning their dynamic behavior. These properties are verified thanks to the use of model checkers. The second approach relies on a theorem prover, the Coq Proof Assistant, to prove dynamic properties of neurons and archetypes.  相似文献   
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