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71.
Composition of fatty acids in virgin olive oils from cross breeding segregating populations by gas chromatography separation with flame ionization detection
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72.
ABSTRACT: Internal atmosphere modification in fruits and vegetables by surface film coatings depends on film permeability, coating thickness, and fruit surface coverage. Research in this area has been mostly empirical, with unpredictable results and diverse conclusions. To reduce variability, it is necessary to have a better understanding of factors that may influence the response of coatings applied to fruits. One factor is relative humidity (RH), which is known to affect the permeability of biopolymer films. By using steady-state mathematical models as tools, we hypothesize that fruits coated with hydrophilic films will be largely influenced by the RH of storage conditions. For hydrophobic materials, RH would have less influence on coating performance. 相似文献
73.
Fruit preservation and packaging have been practiced since ages to maintain the constant supply of seasonal fruits over lengthened periods round the year. However, health and safety issues have attracted attention in recent decades. The safety and quality assurance of packaged fruits/fruit products are vital concerns in present day world-wide–integrated food supply chains. The growing demand of minimally or unprocessed packaged fruits has further aggravated the safety concerns which fuelled in extensive research with objectives to develop novel techniques of food processing, preservation, and packaging as well as for rapid, accurate, and early detection of contaminant products/microbes. Nevertheless, fruits and fruit-based products have yet to observe a panoramic introduction. Tropics and subtropics are the stellar producers of a variety of fruits; majority if not all is perishable and prone to postharvest decay. This evoked the opportunity to critically review the global scenario of emerging and novel techniques for fruit preservation and packaging, hence providing insight for their future implementation. This review would survey key nanotechnology innovations applied in preservation, packaging, safety, and storage of fruits and fruit-based products. The challenges and pros and cons of wider application of these innovative techniques, their commercial potential, and consumer acceptability have also been discussed. 相似文献
74.
ABSTRACT: Whey protein isolate (WPI) films have proven to be excellent gas barriers in previous studies, making them potential coatings for fresh produce. WPI‐coated apples and controls were stored at 20 °;C under RH's ranging from 54 to 92%. Results showed performance of WPI coatings depended on the environment RH. The internal oxygen was lowered, and carbon dioxide increased with decreasing RH conditions. RH did not affect control fruits. At low RH (about 70 to 80% RH), anaerobic respiration was induced in coated fruits due to low oxygen levels (about 0.025 atm). Controlling thickness and film permeability will allow attainment of the appropriate oxygen and carbon dioxide levels for coated fruit. 相似文献
75.
Juan Gómez-Sanchis José D. Martín-GuerreroEmilio Soria-Olivas Marcelino Martínez-SoberRafael Magdalena-Benedito José Blasco 《Expert systems with applications》2012,39(1):780-785
Penicillium fungi are among the main defects that may affect the commercialization of citrus fruits. Economic losses in fruit production may become enormous if an early detection of that kind of fungi is not carried out. That early detection is usually based either on UltraViolet light carried out manually. This work presents a new approach based on hyperspectral imagery for defect segmentation. Both the physical device and the data processing (geometric corrections and band selection) are presented. Achieved results using classifiers based on Artificial Neural Networks and Decision Trees show an accuracy around 98%; it shows up the suitability of the proposed approach. 相似文献
76.
《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2013,30(7):1301-1309
Four samples of paper and board (P/B) of a type used for packaging dry foods were subjected to migration tests using mushrooms, apples, potatoes and bananas, and using the polymeric powder Tenax? as a food simulant. The P/B samples contained only low levels of diisopropylnaphthalene (DiPN) and diisobutyl phthalate (DiBP) and so the experiments were conducted after impregnating the P/B with added model substances. These were o-xylene, acetophenone, dodecane, benzophenone, DiPN and DiBP. Migration levels depended strongly on the nature of the substance and on the nature of the food and much less on the characteristics of the P/B, except insofar as they affected the contact area – flexible papers giving more extensive contact with the food than thick rigid board. Migration into Tenax? was at least a factor of 10 higher than migration into the fresh fruit and vegetables. The food samples were placed in contact with the P/B and then overwrapped loosely with aluminium foil and so this correction factor will tend to be conservative compared with a more open storage of the packed foods. Washing, peeling or cooking the fruits and vegetables after contact with the P/B had a surprisingly small effect on contaminant levels in general, and no one processing step was effective in giving a significant reduction of all the types of chemicals studied. This was because either they had penetrated into the food (so resisting peeling), or were not freely water-soluble (so resisting washing) or were not particularly volatile (so resisting loss by evaporation during cooking). 相似文献
77.
78.
Mahfoozur Rehman Basem A.J.A. Abu Izneid Mohd Zaid Abdullah Mohd Rizal Arshad 《International Journal of Food Science & Technology》2011,46(6):1303-1309
This study deals with the development of a nondestructive impedance spectroscopic technique that may assess the conditions of the fruits to pluck them with the help of robotic arms. Preliminary investigations are made with the help of two‐terminal probe and an accurate LCR meter. The bulk impedance of mango has been measured to characterise raw and ripe fruits. Effective resistance and effective capacitance vs. frequency characteristics have been determined. The bulk effective resistances, of the ripe fruits, are found to be more than those of the raw fruits, in the frequency range of 1–6 kHz. In the same frequency range, effective capacitances of the raw fruits are found more than those of the ripe fruits. In the light of the data obtained, it can be said that the effective resistance may be used to differentiate between raw and ripe fruits in the frequency range of 1–6 kHz. 相似文献
79.
F.N. Arroyo-López J. Bautista-Gallego M.C. Durán-Quintana A. Garrido-Fernández 《LWT》2008,41(4):551-560
The effect of the mixture of sodium metabisulfite (SM), ascorbic acid (AA), and NaCl on the surface colour of fruits and microbial growth during the storage of cracked Manzanilla-Aloreña table olives was studied. During storage, the green colour of fruits, measured by the hue angle (tang−1(b/a)), decreased rapidly, indicating a degradation in the green and a change towards more reddish tones. The degreening rate (kc) was lower for the highest AA concentration, while the highest final hue angle was found for the highest SM level, indicating different antioxidant mechanisms. Enterobacteriaceae were not enumerated after 20 days of brining. AA, SM, and NaCl, within the concentrations essayed, did not affect yeast growth; however, lactic acid bacteria (LAB) were partially inhibited by the presence of SM and AA, showing the highest growth rate in the absence of both. The maximum population of LAB was reached at levels of SM below 0.75 g/l, intermediate AA (7.5 g/l) and NaCl (70 g/l) concentrations. Appropriate storage conditions could be obtained at the maximum levels of AA (15.0 g/l) and SM (1.5 g/l) and the lowest level of NaCl (60 g/l). 相似文献
80.
Iris C. Zampini Roxana Ordoñez Norberto P. Giannini Pedro G. Blendinger María Inés Isla 《Food research international (Ottawa, Ont.)》2011,44(7):2345-2351
Fruits are known as good sources of phytochemicals, essential to prevent degenerative diseases like cancer and cardiovascular diseases. They contain a variety of antioxidants, which are useful to scavenge radical oxygen species (ROS). Considering the importance of natural products as a functional food, comparative studies between the antioxidant activity (AOA) and antimutagenic properties as well as phytochemical profile of Cactaceae fruits (Lepismium lorentzianum, Lepismium lumbricoides, Rhipsalis floccosa, and Pfeiffera ianthothele) from Argentinean Yungas, were performed. Different assays were applied: ABTS radical scavenging capacity, inhibition of lipid peroxidation using ??-carotene-linoleate model system and mutagenicity/antimutagenicity by Ames test. A pigment like betalain was detected in fruits of both Lepismium species; L. lorentzianum aqueous extracts showed a higher pigment content (60.6 mg BE/100 g FM) than L. lumbricoides (9.2 mg BE/100 g FM). Fruit preparations of L. lorentzianum (aqueous and ethanolic extractions) showed significantly higher total phenolic compound and pigments content than the other berries. In all preparations, high antioxidant activity was demonstrated. Lepismium species were more active than Rhipsalis and Pfeiffera (SC50ABTS values between 1.3 and 4.5 ??g/ml and IC50 ??-carotene-linoleate values between 9 and 45.8 ??g/ml). A significant correlation between pigment and phenolic compounds content and AOA was observed. The preparations showed no sign of mutagenicity at tested concentrations (until 50 ??g/plate). A significant antimutagenic effect was observed for L. lumbricoides, and a weak effect was shown for P. ianthothele and R. floccosa. Because of the diversity and abundance of bioactive phytochemicals found in these species, food, cosmetic, and pharmaceutical applications could be proposed. 相似文献