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1.
This paper presents the foundations for building mobile environmental information systems (MEISs) requiring an interdisciplinary approach. MEISs require expertise from the disciplines of environmental biology, geography, and mobile technology. MEISs show great promise for the acquisition of environmental information using different mobile devices. Automatic mobile acquisition enables the forwarding of the information to central databases for storage, further processing, and transmission to the mobile devices in a form that is useful to the users. Furthermore, these systems have the potential to be used both in the protection of nature, as well as in recreational use in a way that takes the constraints of nature into account. In this paper we describe the preliminary results of the MINNE project and the prototypes currently under research in the project.  相似文献   
2.

ABSTRACT

This report describes Citrus sinensis fruit grown in the Lake Maggiore area (Italy), the upmost Northern distribution range of the genus Citrus in Europe. Total ascorbic acid (TAA), bioflavonoids, total polyphenol content (TPC), antioxidant activity, total soluble solid, total acidity and sensory characteristics were evaluated on oranges harvested during the 2009–2010 season. The range of values detected was as follows: TAA from 36.89 to 67.34 mg/100 mL, hesperidin from 18.97 to 31.87 mg/100 mL, narirutin from 17.30 to 29.28 mg/100 mL and rutin from 4.39 to 5.36 mg/100 mL; antioxidant activity (ferric reducing antioxidant power assay) from 8.62 to 17.00 mmol Fe2+/kg, fresh fruit weight; TPC (Folin–Ciocalteu method) from 87.16 to 135.16 mg GAE/100 g. This first attempt to characterize cultivars grown in the Piedmont region showed that these oranges had acceptable nutritional components and sensory quality, if compared with bibliographic data about cultivars grown in the subtropical and Mediterranean area.

PRACTICAL APPLICATIONS

The identification, characterization and valorization of old cultivars are essential to avoid loss of potentially useful germplasm. The reduction of biodiversity of cultivars found in agriculture could lead to problems such as higher susceptibility to widespread outbreaks of plant diseases and pests, and at the same time, the loss of precious source of nutrients. This survey was carried out to characterize a germplasm that could also be used in breeding programs to obtain new cold‐tolerant varieties.  相似文献   
3.
Glial cells are crucial for maintaining central nervous system (CNS) homeostasis. They actively participate in immune responses, as well as form functional barriers, such as blood-brain barrier (BBB), which restrict the entry of pathogens and inflammatory mediators into the CNS. In general, viral infections during the gestational period can alter the embryonic and fetal environment, and the related inflammatory response may affect neurodevelopment and lead to behavioral dysfunction during later stage of life, as highlighted by our group for Zika virus infection. Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) induces a cytokine storm and, during pregnancy, may be related to a more severe form of the coronavirus disease-19 (COVID-19) and also to higher preterm birth rates. SARS-CoV-2 can also affect the CNS by inducing neurochemical remodeling in neural cells, which can compromise neuronal plasticity and synaptic function. However, the impact of SARS-CoV-2 infection during pregnancy on postnatal CNS, including brain development during childhood and adulthood, remains undetermined. Our group has recently highlighted the impact of COVID-19 on the expression of molecular markers associated with neuropsychiatric disorders, which are strongly related to the inflammatory response. Thus, based on these relationships, we discussed the impact of SARS-CoV-2 infection either during pregnancy or in critical periods of neurodevelopment as a risk factor for neurological consequences in the offspring later in life, focusing on the potential role of glial cells. Thus, it is important to consider future and long-term public health concerns associated with SARS-CoV-2 infection during pregnancy.  相似文献   
4.
The kinetics of thiamin degradation in a model system of pH 6.0 and water activity (aw) 0.95 controlled with NaCl, KC1, glycerol or Na2SO4, was studied. The type of solute used to adjust aw, had a dramatic influence on the rate of degradation of thiamin. The loss of vitamin increased in the following order: NaCl > KCl > glycerol > Na2SO4. Activation energies, however, were independent of the type of solute and ranged between24–28 kcallmole.  相似文献   
5.
Literature data for the rates of thiamine destruction in a wide variety of model systems, buffer solutions and foods have been used to determine the kinetics of thiamine destruction during processing. A range of conditions, including temperature, pH, oxygen and catalysts indicate that, in most cases, the destruction of thiamine follows first order reaction kinetics. When information is limited, these calculations may be used to extrapolate data and predict modifications of processing to minimize losses of thiamine.  相似文献   
6.
We have determined the nucleotide sequence of a segment of chromosome VII of the yeast Saccharomyces cerevisiae contained in the cosmid clone pEGH101 for a total of 7 kbp. This sequence contains a large open reading frame (ORF) called G9365, coding for a protein of 1967 amino acids that shows a significant homology with the product of the SKI2 gene of S. cerevisiae and contains domains characteristic of RNA-helicases. The ORF is transcribed in vegetative cells but it is not essential for viability as demonstrated by gene disruption. The sequence has been deposited in the GenBank data library under Accession Number U35242. © 1997 John Wiley & Sons, Ltd.  相似文献   
7.
This paper reports experimental results on cochannel interference during rain, derived from measurements of simultaneous and copolar rain attenuations, in the 20 GHz band, in two convergent slant paths to fixed receivers at Spino d'Adda (Northern Italy), from the geostationary satellites Olympus (19°W) and Italsat (13°E). The results show that during rain the interference can be larger than that in clear sky, with probability 0.5 and that, in this case, the interfering level I = AC − An (dB), i.e. the difference between the simultaneous rain attenuations (dB) in the interfered path, AC (dB), and in the interfering path, An (dB), increases as the system power margin increases. For system design, the paper reports the cumulative distributions of I, conditioned to the maximum value of the attenuation not exceeded (i.e. system power margin) in the interfered link. It is shown how the results could be used in systems with regenerative or transparent transponders on board.  相似文献   
8.
ABSTRACT

This work presents a methodology far obtaining heat and mass transfer coefficients for problems involving natural convection along a flat plate. In order to simulate drying conditions, a set of data has been obtained for the temperature range between 20 and 98° C and for various absolute humidities, both of the wall and ambient. It is shown that for drying at temperatures above 80° C, Nusselt and Sherwood numbers change very appreciably with respect to values obtained at smaller temperatures. The simulated results show that even for very low temperature differences, the transient period in natural convection along a flal vertical plate is smaller than 3s.  相似文献   
9.
Polycyclic aromatic hydrocarbons (PAHs) and nitrated polycyclic aromatic hydrocarbons (nitro-PAHs) were identified from both air particulate matter and soils. For air sampling, a six-stage cascade impactor was situated in an urban area (Catania, Italy) that is recognized for its high traffic volume. The soil samples were collected every 1.5 km from under the grass by the side of the median of a Catania road along its full length (8.2 km). HPLC in electrochemical-fluorescence detection mode was used for selective separation, identification and quantification of analytes in air and soil samples, providing both good selectivity and sensitivity. The seasonal trends, effects of urban traffic, and source profiles are discussed herein. Higher PM10 concentrations were observed for summer (43 μg m?3) in comparison to winter (24 μg m?3). Conversely, the PAHs contained in PM10 were higher in winter (0.48 ng m?3 for fluoranthene) than in summer (0.14 ng m?3 for fluoranthene). Analysis of the size-segregated urban particulate matter showed that the amount of PM0.5 (stage 6) was always higher than the amount of other particles (stages 1–5). Furthermore, the PM0.5 was always higher in summer (about 40%, m/m) than in winter (about 30%, m/m). Finally, the amounts of PAH and nitro-PAH in PM0.5 (stage 6) were always higher, by a maximum of one order of magnitude, than that of other particles (stages 1–5). This result is crucial because ultrafine particles have a tendency to move into the blood through the alveolar epithelial barrier. Moreover, the air and soil pollution levels agree with those found in other cities with similar levels of pollution. Supplemental materials are available for this article. Go to the publisher's online edition of Polycyclic Aromatic Compounds to view the supplemental file.  相似文献   
10.
The propagator of the unsteady Stokes equation is shown to be dominated by the solution of a purely diffusive equation, whose dispersion coefficient is the viscosity. Pressure plays an indirect role only, by creating instantaneously a steady velocity field which decays slowly in space. Viscosity appears to measure the temporal growth of the second moment of the unsteady Stokes propagator.  相似文献   
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