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91.
92.
Sandra P.O Dwyer David OBeirne Deirdre Ní Eidhin Brendan T. OKennedy 《Journal of food science》2012,77(12):N58-N65
Abstract: This study examined the effectiveness of fat and water soluble antioxidants on the oxidative stability of omega (ω)‐3 rich table spreads, produced using novel multiple emulsion technology. Table spreads were produced by dispersing an oil‐in‐water (O/W) emulsion (500 g/kg 85 camelina/15 fish oil blend) in a hardstock/rapeseed oil blend, using sodium caseinate and polyglycerol polyricinoleate as emulsifiers. The O/W and oil‐in‐water‐in‐oil (O/W/O) emulsions contained either a water soluble antioxidant (green tea extract [GTE]), an oil soluble antioxidant (α‐Tocopherol), or both. Spreads containing α‐Tocopherol had the highest lipid hydroperoxide values, whereas spreads containing GTE had the lowest (P < 0.05), during storage at 5 °C, while p‐Anisidine values did not differ significantly. Particle size was generally unaffected by antioxidant type (P < 0.05). Double emulsion (O/W/O) structures were clearly seen in confocal images of the spreads. By the end of storage, none of the spreads had significantly different G′ values. Firmness (Newtons) of all spreads generally increased during storage (P < 0.05). Practical Application: Lipid oxidation is a major problem in omega‐3 rich oils, and can cause off‐odors and off‐flavors. Double emulsion technology was used to produce omega‐3 enriched spreads (O/W/O emulsions), wherein the omega‐3 oil was incorporated into the inner oil phase, to protect it from lipid oxidation. Antioxidants were added to further protect the spreads by reducing lipid oxidation. Spreads produced had good oxidative stability and possessed functional (omega‐3 addition) properties. 相似文献
93.
Effects of slaughter weight and sex on carcass characteristics and lamb meat quality of Manchega Spanish breed were analysed. Forty-five lambs were divided into two slaughter weight groups: light (LW=21.7±0.16 kg; n=24) and medium (MW=27.8±0.16 kg; n=21). Dressing proportion and conformation were significantly different between groups and sex. There were also differences between light and medium group in fatness but not between males and females. Water holding capacity decreased with increasing slaughter weight (p<0.05) and was lower in females than in males (p<0.001). The increase in weight was associated with a decrease in L* (p<0.01), while a* showed an increase which failed to reach statistical significance. Slaughter weight and sex affected neither pH and its decrease post-slaughter nor meat toughness. ? 相似文献
94.
Thermoneutrality results in prominent diet‐induced body weight differences in C57BL/6J mice,not paralleled by diet‐induced metabolic differences 下载免费PDF全文
95.
Sandra Cortés M Luisa Gil Esperanza Fernández 《Journal of the science of food and agriculture》2009,89(7):1221-1226
BACKGROUND: The distillation of vinification by‐products to obtain alcoholic drinks is potentially an important source of income for the producing countries and avoids the environmental problem of waste management. Traditional technologies of distillation involve an important cost in terms of time and staff. Nowadays, companies install new distillation equipment, with high capacity and equipped with rectification columns, which is an important advance. Nevertheless, few studieshave been published concerning their correct management. In this study, the major volatile compounds were determined by gas chromatography in 61 samples of grape pomace distillate, corresponding to the fractions collected during seven complete distillation cycles. RESULTS: With a high degree of significance, the concentrations of 1,1‐diethoxyethane, propanol, hexanoate and ethyl acetate present positive correlations with the ethanol. However, those of benzyl alcohol, 2‐phenylethanol, furfurol, lactate, ethyl mirystate and diethyl succinate, were negative, which indicates that both groups of compounds were vented in the fractions of major or minor alcoholic degree, respectively. In addition, knowledge of the relationships between the volatile compounds contributes to improved management of an industrial distillation unit. CONCLUSION: The correlations established between the concentrations of the different volatile compounds indicate their physico‐chemical affinities or their biochemical origin. Copyright © 2009 Society of Chemical Industry 相似文献
96.
Chunbao Li Slawomir Szczepaniak Liselot Steen Olivier Goemaere Sandra Impens Hubert Paelinck Guanghong Zhou 《International Journal of Food Science & Technology》2011,46(10):2159-2163
This study evaluates effect of tumbling time and cooking temperature on cooking rate, cooking loss (CL), colour, water activity and water‐holding capacity of cooked restructured ham rolls. In experiment were investigated three tumbling times (2, 4 and 6 h) at constant temperature (+4 °C) and three cooking temperatures (76, 86 and 96 °C). It was observed that CL decreased (P < 0.01) from 5.41% to 3.22% with tumbling time (2 h vs. 6 h) but increased (P < 0.01) from 2.35% to 7.25% along with cooking temperature (76 °C vs. 96 °C). In contrast, pH value increased (P < 0.01) from 6.18 to 6.24 with tumbling time (2 h vs. 6 h) but decreased (P < 0.01) from 6.22 to 6.17 along with cooking temperature (76 °C vs. 96 °C). In addition, high temperature had higher efficiency for thermal lethality than low temperature (F0 values were 19 and 92 min at 96 and 76 °C, respectively). Intermediate tumbling (4 h) and cooking (86 °C) could be preferential. 相似文献
97.
Sensory Characterization and Consumer Preference Mapping of Fresh Sausages Manufactured with Goat and Sheep Meat 下载免费PDF全文
Kátia Paulos Sandra Rodrigues António Filipe Oliveira Ana Leite Etelvina Pereira Alfredo Teixeira 《Journal of food science》2015,80(7):S1568-S1573
The main objective of this study was the sensory characterization, by a taste and a consumers’ panel, of fresh sausages from 140 culled goats and 140 culled ewes. Species and type of preparation effects were studied. All data were previously analyzed by analysis of variance. Taste panel data were analyzed by a Generalized Procrustes Analysis (GPA). Consumers’ panel data were analyzed by Preference Mapping. The 1st 2 factors explained 88.22% of total variation in GPA. Different sausages samples were perfectly differentiated by assessors. Goat sausages have been considered harder, more fibrous, and less juicy than sheep sausages. The panelists observed that sheep sausages without paprika had greater intensity of flavor, tasted spicy, and had an off‐odor, while goat sausages with paprika were considered sweeter. Consumers’ panel did not show any preference for the different types of sausages. This means that all types of sausages can have market opportunity. 相似文献
98.
Requested raw data from a sample of authors in 1 issue of 4 psychological journals which vary from "hard" to "soft" scientific methodology in the articles published. Despite differences between the authors in the "hard" and "soft" journals, replies indicate that at present there is a greater tendency toward sharing data than has been reported previously. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
99.
Sandra Borges Joana Barbosa Joana Silva Ana M. Gomes Manuela Pintado Cristina L. M. Silva Alcina M. M. B. Morais Paula Teixeira 《International Journal of Food Science & Technology》2016,51(2):381-388
The aim of this study was to develop fruit powders (apple, banana and strawberry) enriched with a probiotic strain (Lactobacillus plantarum 299v). Two methodologies were proposed: (i) drying of the fruit with probiotic culture incorporated (by convection) or (ii) drying of fruit (by convection) and addition of spray‐dried probiotic culture. In the first methodology, processing caused a notable reduction in probiotic viable counts in apple, but this reduction was lower during drying of banana and strawberry. A large reduction in viable cells was also recorded during storage. In the second methodology, the survival of L. plantarum 299v was considerably higher during spray‐drying, and fruit powders with a microbial content suitable for a probiotic food (108–109 cfu g?1) were obtained. The fruit powders incorporating L. plantarum 299v can be stored at 4 °C or at room temperature, for at least 3 months. This preliminary study demonstrated that fruit powders are good carriers of probiotic cultures, but the techniques used to produce them should be carefully considered. 相似文献
100.
Joo Pissarra Sandra Loureno Jos Maria Machado Nuno Mateus David Guimaraens Victor de Freitas 《Journal of the science of food and agriculture》2005,85(7):1091-1097
The commercial wine spirit used for this study revealed that the aldehyde content mainly comprises acetaldehyde but other aldehydes such as propionaldehyde, 2‐methylbutyraldehyde, isovaleraldehyde, methylglyoxal, benzaldehyde and others are also present in significant amounts. A typical grape must was used to assess the influence of wine spirit in the analytical and sensorial characteristics of fortified wines. Decreasing levels of anthocyanins, as well the increase in the red colour and tanning capacity, were observed, and seem to be positively correlated with the increase of the aldehyde content present in the wine spirits used to fortify the must. Using the CIE L*a*b* system, this aldehyde content present in the spirit used seemed to be correlated with the decrease of the wines' lightness (darkening effect), the displacement of the hue angle to higher values (yellowing effect) and the increase of the chromaticity (colour saturation) of the wines. Copyright © 2005 Society of Chemical Industry 相似文献