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11.
De La Torre Jessica Elizabeth Fatma Gassara Anne Patricia Kouassi Khaled Belkacemi 《Critical reviews in food science and nutrition》2017,57(6):1078-1088
Spices are parts of plants that due to their properties are used as colorants, preservatives, or medicine. The uses of spices have been known since long time, and the interest in the potential of spices is remarkable due to the chemical compounds contained in spices, such as phenylpropanoids, terpenes, flavonoids, and anthocyanins. Spices, such as cumin (cuminaldehyde), clove (eugenol), and cinnamon (cinnamaldehyde) among others, are known and studied for their antimicrobial and antioxidant properties due to their main chemical compounds. These spices have the potential to be used as preservatives in many foods namely in processed meat to replace chemical preservatives. Main chemical compounds in spices also confer other properties providing a variety of applications to spices, such as insecticidal, medicines, colorants, and natural flavoring. Spices provide beneficial effects, such as antioxidant activity levels that are comparable to regular chemical antioxidants used so they can be used as a natural alternative to synthetic preservatives. In this review, the main characteristics of spices will be described as well as their chemical properties, different applications of these spices, and the advantages and disadvantages of their use. 相似文献
12.
Omer Said Toker Fatma Tugce Zorlucan Nevzat Konar Orhan Dağlıoğlu Osman Sagdic Dilek Şener 《International Journal of Food Science & Technology》2017,52(3):788-799
Chocolate compound was produced using ball mill refiner, and the effect of agitator shaft speed and refining time on the physical quality parameters (particle size, colour and steady‐state rheology) of compound chocolate was determined using response surface methodology. The shaft speed and refining time range were selected between 40–60 r.p.m. and 10–30 min, respectively. Determination coefficient of the models established for particle size, Newtonian viscosity and colour parameters (brightness, chroma and hue angle) were found to be very close to unity. Increasing shaft speed and time induced a reduction in particle size and an increase in viscosity of the samples. Temperature sweep test was also performed, and the obtained data were successfully fitted to Arrhenius equation to calculate the corresponding parameters representing temperature dependency of the compounds. The results highlighted that the establishment of such models can provide essential information in terms of optimisation of production processes regarding usage purpose of the compound chocolate. 相似文献
13.
Effect of several physical treatments (soaking, dehulling, ordinary cooking, microwave cooking, and autoclaving) on the level
of antinutrients and in vitro protein digestibility of bitter and sweet lupin seeds were investigated. The raw bitter and sweet lupin seeds were found
to contain phytic acid, tannins, trypsin inhibitor activity, and lectin activity, but α-amylase inhibitor was absent. Dehulling
significantly increased the levels of phytic acid (PA), trypsin inhibitor activity (TIA), and tannins, but lectin activity
was not changed. Also soaking in bitter (for 96 hr) and sweet (for 24 hr) seeds caused a significant increase in these factors
except lectin activity. Cooking methods differently affected the levels of the antinutrients. Thus, PA increased but tannins
were not changed, on the other hand TI and lectin activities were inactivated; ordinary cooking and autoclaving were the most
effective in both seeds. For combination effect, soaking following cooking treatments significantly decreased PA, tannins,
and lectin activity, but increased TIA in both seeds. Moreover, dehulling following soaking and cooking methods resulted in
a significant increase of PA, TIA, and tannins. In vitro protein digestibility (IVPD) of raw bitter and sweet lupin seeds were 78.55 and 79.46%, respectively and it was improved
by all processing methods; soakingdehulling after autoclaving was the most effective in both seeds. Although some treatments
increased the level of antinutrients, they improved IVPD. Therefore, the studied antinutrients are not the only responsible
factor for lowering IVPD. 相似文献
14.
M.M. El-Sayed F.F. Abdel Hamid Y.M. Ahmed S.H. Ali O.Y. Mansour N.M. Abdallah 《Molecular nutrition & food research》1998,42(1):12-15
Efforts have been done to recover proteins from waste liquors rich in protein in a soluble form. Cheese whey and animal bloods are byproducts from the manufacture of cheese and meat. It contains a variety of proteins which can be reclaimed. The efficiency of protein precipitation from the sweet-cheese whey by the use of hydroxyethyl cellulose (HEC) was similar to that precipitated by the use of carboxymethyl cellulose (CMC). Both are greater than that precipitated by trichloro acetic acid. The same results of the efficiency of precipitation were attained when the plasma protein was precipitated. It was found that cheesewhey protein-HEC-complex and plasms protein-HEC-complex contain a large amount of essential amino acids. Electrophoretic separation of whey protein complex showed that β-Lactoglobulin forms the major fraction while in case of plasma protein complex albumin forms the major fraction. The fractionation patterns of different complexes with HEC, CMC or TCA gave the same components and about the same ratio. It appears from these results that HEC-protein complexes are preferable than CMC-protein complexes or proteins precipitated by TCA. Chemical analysis of whey protein complexes revealed that lactose content of whey protein-HEC-complex was higher than that of CMC-complex or protein precipitated by TCA. Elemental analysis of protein complexes showed that the level of sodium, phosphorus, and potassium was increased while that of copper or zinc decreased. Cellulose derivative protein complexes showed no significant effects on the liver or kindney function of albino rat and these results indicated that no toxic effect was observed from the uses of these protein complexes in feeding. 相似文献
15.
16.
Biochemical and thermal properties of β-galactosidase enzymes produced by artisanal yoghurt cultures
β-Galactosidases, produced by pure and mixed cultures of Streptococcus thermophilus 95/2 (St 95/2) and Lactobacillus delbrueckii ssp bulgaricus 77 (Lb 77) isolated from the Toros mountain region of Turkey, were characterised with respect to their biochemical and thermal properties. Optimum pH and temperature for maximum activity were determined and these enzymes were stable in the pH range 7–9 and in the temperature range 20–37 °C, retaining 80–90% of their initial activities. The inactivation energies of β-galactosidase from Lb 77, St 95/2 and mixed culture (Lb 77 and St 95/2) were 51.3, 44.0 and 48.3 kcal mol−1, respectively. Moreover, thermodynamic (ΔG, ΔS, ΔH) and kinetic constants (Km and Vmax) were determined and effects of metal ions were investigated. As a result, these enzymes could be considered as potential candidates for lactose hydrolysis of milk and milk products. 相似文献
17.
Food Science and Biotechnology - The main objective of this study was to examine the phenolic compounds and the antibacterial, antioxidant, anti-α-glucosidase and anti-α-amylase... 相似文献
18.
Fatma Osman Ibnouf 《Food Security》2011,3(2):215-231
This paper investigates the role of women in achieving household food security in the Western Region of Sudan, an area much
affected by the impacts of drought and civil conflicts. The study is based on a quantitative survey and qualitative focus
group discussions, supported by personal observations made during fieldwork. Additionally, the study draws upon secondary
data that is publicly available. Results demonstrate that women play a major role in producing and providing food for their
households in this high-risk climate and conflict area, while men are more likely to migrate seasonally and even permanently.
In addition, women are responsible for food preparation, processing, and food preservation and are wholly responsible for
attending to household garden plots. They therefore contribute more to household food security than men, though this contribution
is not recognized in official statistics. The study findings indicate that the main problems women face as food producers
and providers are a lack of access to the full package of improved production methods (improved seeds, fertilizers, modern
farming methods, credit services, pesticides, appropriate technologies, and marketing facilities), in addition to gender disparities
and gender-biased traditions. The impacts of natural crises and civil conflicts are gendered and therefore the responses to
these crises must be gender responsive. Holistic and strategic policies and plans that take gender issues into account are
thus needed in order to achieve food security. 相似文献
19.
El-Sayed M. Abdel-Aal Piere Hucl S. Shea Miller Carol Ann Patterson Danielle Gray 《Food chemistry》2011
Canary seed is a true cereal with unique composition. The current study employed light and fluorescence microscopy to visualise starch, protein, phenolics and phytate in hairless canary seed (CDC Maria), a cultivar developed potentially for food use. Macronutrients, minerals and vitamins were evaluated in the developed cultivar and compared with a commercial hairy canary seed, cv. Keet. A control common wheat, cv. Katepwa, was grown adjacent to the canary seed varieties. The compositions of the two canary seed varieties were found to be similar with an average of 55.8 g/100 g of starch, 23.7% g/100 g of protein, 7.9% of crude fat, 7.3 g/100 g of total dietary fibre, 1.8 g/100 g of soluble sugar and 2.3 g/100 g of total ash in the whole grain. Regardless of the milling fraction (whole grain flour, white flour or bran), canary seed had more protein and crude fat and less starch, total dietary fibre and soluble sugar than had wheat. It also had higher concentrations of several minerals and vitamins than did wheat. The structure of the canary seed grain exhibited compound starch granules and protein bodies embedded in a protein matrix similar to that of the oat kernel. Baking tests showed that bread made with 100% hairless canary seed flour was significantly lower in loaf volume and crust and crumb colour than was wheat bread. However, bread with loaf volume, specific volume and crust colour comparable to those of the bread control was achieved by using up to 25% of hairless canary seed or 15% of roasted canary seed flour, thus demonstrating its potential for food applications. 相似文献
20.
The effects of various treatments and frying times on some physical, chemical, and sensorial properties of potato balls coated
with chickpea and wheat flour were studied. Potato balls were pre-dusted with chickpea flour (CF) or wheat flour (WF) as an
initial coating which was followed by dipping into 0.1% xanthum gum solution as the second coating. The last coating was breading
with 1:3 CF/WF, 1:1 CF/WF, and 3:1 CF/WF mixtures. Coated potato balls were fried at 185 °C for 5, 7, and 9 min. The pre-dusting
materials, particularly the effect of CF, enhanced yield values and sensorial properties as well as increased adhesion degree
as it decreased frying loss. Although, the breading materials raised the yield values compared to the control, the yield and
moisture content values decreased with increasing frying time. Frying loss, fat absorption, penetrometer values, and texture
values also increased. Results revealed that CF is suitable as a pre-dusting material, and 7 min was the more efficient frying
time for coated potato balls. 相似文献