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1.
Vincenzo Lo Turco Angela Giorgia Potortì Alessia Tropea Ermina Katia Casale Maria Rita Fede 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2016,33(11):1693-1699
Twenty-six plasticisers and bisphenol A (BPA) in 39 Sicilian and Calabrian nectar honeys of different botanical south Italian origin were determined by GC-MS. Di-(2-ethylhexyl)phthalate was the most abundant plasticiser in all samples, reaching up 202.7 ± 153.1 µg kg–1, followed by di-butylphthalate with a concentration of 40.3 ± 9.3 µg kg–1, whereas the concentration of the other phthalates varied from not detectable to 68.2 µg kg–1. Trace levels of adipate, sebacate and BPA were not detected in any samples. Among the different floral origin honeys, di-ethylphthalate levels were above the limit of quantification (LOQ) in orange blossom, wildflower and chestnut honey samples. Among the honeys of different geographical origin, di-methylphthalate, di-butylphthalate and di-(2-ethylhexyl)phthalate concentrations were similar. Calabrian honeys showed levels of di-ethylphthalate always lower than the LOQ, moreover di-(2-methylpropyl)phthalate levels were lower than the Sicilian ones. On the contrary, in Sicilian honeys di-(2-methylpropyl)phthalate levels were higher and di-ethylphthalate was present in 37% of samples. 相似文献
2.
This review discusses the processing techniques proposed for the production of dried and intermediate moisture honey products, as well as their properties. Stickiness is the major problem in the drying of sugar rich products like honey, that depend on the type of sugar and temperature of operation, which are related to the glass transition temperature. Some additives are usually added to the sugary feed to increase the glass transition temperature and concurrently the sticky point temperature. In the case of honey-fruit spreads, nutritional and sensory characteristics can be enhanced by replacing part of sugar with honey. Co-crystallization of honey with sucrose could be used to preserve the honey flavor. These diversified honey products provide better taste and nutrition to the consumer besides enhancing the utilization of honey. 相似文献
3.
4.
Evaluation of the phenolic content,antioxidant activity and colour of Slovenian honey 总被引:1,自引:0,他引:1
Honey samples from the seven most common honey types in Slovenia were screened for total phenolic content by the modified Folin–Ciocalteu method, for potential antioxidant activity using the ferric reducing antioxidant power (FRAP) assay and by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) method for antiradical activity. In addition the colour characteristics of honey samples were analysed. The results of the study showed that total phenolic content, antioxidant activity and colour parameters differ widely among different honey types. Phenolic content expressed as gallic acid equivalent ranged from 44.8 mg/kg in acacia honey to 241.4 mg/kg in fir honey. Antioxidant activity was the lowest in the brightest acacia and lime honeys and the highest in darker honeys, namely fir, spruce and forest. The colour of the Slovenian honeys, analysed in this study was very variable and ranged from pale yellow to dark brown. Correlations between the parameters analysed were found to be statistically significant (p < 0.05). 相似文献
5.
The complex and variable composition of honey, depending on source, season and processing, means different honey samples could cause variation in the characteristics of the finished product. The objective of this study was to determine how the minor components present in honey affect starch gelatinization. A Rapid Visco Analyser was used to measure changes in viscosity when unmodified maize starch was gelatinized in a honey or model sugar solution. When honey was compared to equivalent blends of sugars, there was an increase in starch viscosity with increasing levels of addition. However, at the same level, honey gave a lower viscosity than the blends of sugars. Honeys from different sources (differing in pH and amylase activity) show a varied effect on starch gelatinization, with starch viscosity increasing with addition level for six of the honeys, but decreasing with increasing addition level for two honey samples. Varying the pH also produced variation in starch gelatinization patterns between honey types. Between pH 3.0 and 4.0, starch viscosity was similar for all four honey types studied, while above this pH there were differences between all honey types. As expected, starch viscosity decreased as the solution pH neared the optimum for honey amylase activity (pH 5.3-5.6), though it did not increase as the pH moved away from the honey amylase activity optimum. Differences between honey samples, and between honey and a model sugar mixture, in their effect on starch gelatinization was attributed to honey amylase activity and the composition and concentration of minor organic compounds present. 相似文献
6.
Detection of glyphosate and its metabolites in food of animal origin based on ion-chromatography-high resolution mass spectrometry (IC-HRMS) 总被引:1,自引:0,他引:1
Luca Maria Chiesa Maria Nobile Francesco Arioli 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2019,36(4):592-600
Glyphosate and glufosinate are broad spectrum herbicides, widely used in agriculture and in inhabited or industrialised areas, and aminomethylphosphonic acid is a degradation product of glyphosate. In 2015, the International Agency for Research on Cancer reported that glyphosate is a probable carcinogenic. In 2017, however, a scientific opinion of the European Chemicals Agency concluded that glyphosate is not proven to be carcinogenic, mutagenic or to have negative effects on reproduction. Nevertheless, aminomethylphosphonic acid was not considered. Due to their chemical-physical characteristics, these molecules present difficulties that have not yet allowed routine monitoring to be carried out. For these reasons, we developed and validated a simple and versatile liquid extraction, before IC-HRMS analysis, of three different complex matrices: honey, bass fish and bovine muscle. Among the satisfactory validation parameters, the LOQs in the range of 4.30–9.26 ng g?1 demonstrated high method sensitivity, compared to the few works present in literature. Finally, the method was applied to real commercial samples, which showed no traces of the selected pesticides. 相似文献
7.
为了使蜂蜜柑橘酒品质稳定,通过对后发酵蜂蜜柑橘原酒进行澄清的研究,结果表明,添加1%壳聚糖和0.1%明胶澄清,室温静置24h为最佳的澄清方法,而且对蜂蜜柑橘酒的品质影响较小,可溶性固形物的保存率达97.2%,还原糖的保存率达97.6%,1-总酸的保存率达94.3%. 相似文献
8.
An ultrasonic method, based on the measurement of the complex reflection coefficient at an interface (elastic material)/(viscoelastic material) has been developed for shear waves and an operating frequency of 10 MHz. With this technique, the dynamic elastic moduli G′ and G′′ can be obtained with a high accuracy. For various honeys and moisture contents we show that the temperature for which (G′′/G′) = 1 undergoes an important variation (25–3 °C) for moisture contents ranging from 15% to 20%. With this technique one can distinguish two honeys with moisture contents difference less than 0.2%. Regarding the high sensitivity of the method, considering the fact that ultrasonic waves can propagate through optically opaque materials and is a nondestructive approach, we propose a discussion about the application of this technique for honey quality control. 相似文献
9.
Fourier-transformed infrared spectroscopy has been established for analysing most of the physical–chemical parameters of honey.
Additionally this technique can be used for determination of the botanical origin of a honey sample by comparison of the mid-infrared
spectra. In this study calibrations for authentification of the main regional honey types should be developed to be able to
measure simultaneously physical–chemical properties and the botanical origin at a minimum of time and at low costs. Honey
samples from local beekeepers were collected and characterized by standard methods. The most common honey types were used
for calibration. We recorded the mid infrared spectrum from each honey sample. Classification models were achieved by PCA-calibration
and validated with samples from various botanical origins. Honey of Brassica spp., Robinia pseudoacacia, Calluna vulgaris, Trifolium spp., Tilia spp., Helianthus annuus, Centaurea cyanus and honeydew honey was used for calibration. Afterwards the calibration models were improved during routine analysis. Most
of the honey samples from rape, false acacia, heather and honeydew can be classified correctly by the FTIR in consideration
of the physical–chemical and sensorial properties. 相似文献
10.
Dielectric properties of honey adulterated with sucrose syrup 总被引:2,自引:0,他引:2
Sucrose syrup is a common additive in honey adulteration. To provide information for developing a cheap, simple, convenient and rapid sucrose-adulterated honey detector or sucrose content sensor, the permittivities of pure jujube, yellow-locust and milk-vetch flower honey, pure sucrose syrup and honey-sucrose syrup mixtures with sucrose content from 0% (pure honey) to 80% (pure sucrose syrup) were studied from 10 to 4500 MHz with open-ended coaxial-line technology and a network analyzer at room temperature. The correlations between permittivities and sucrose contents were regressed. The results showed that the dielectric constants of all samples decreased with increasing frequency, while the pure honey had higher dielectric constant than pure sucrose syrup. Dielectric relaxation existed in all samples. The maximum loss factor decreased with increasing sucrose content. The relaxation frequency changed very little with sucrose content. Strong negative linear correlation, R2 > 0.98, was found between loss factor around the relaxation frequency and sucrose content. 相似文献