Search results for "COMPOSITION"
showing 10 items of 2675 documents
Chemical and spectroscopic characteristics of the wood of Vitis vinifera cv. Sangiovese affected by esca disease.
2009
Chemical and spectroscopic analyses ((13)C cross-polarization-magic angle spinning NMR and attenuated total reflection Fourier transform infrared spectroscopies) were carried out on the wood of Vitis vinifera cv. Sangiovese with brown-red discoloration and black streaks caused by esca disease. The analyses of the brown-red wood revealed the destruction of hemicelluloses and noncrystalline cellulose as well as modifications in the pectic and ligninic wood fractions. The pectic fraction consisted of carbohydrates associated with polyphenols. The lignin fraction exhibited only a few changes in the aromatic systems and a partial demethylation, and it appeared to be associated with condensed phe…
Physicochemical and sensory fruit characteristics of two sweet cherry cultivars after cool storage
2002
Physicochemical and sensory fruit characteristics were studied to assess the effects of cool storage on quality attributes of sweet cherries of the Sciazza variety, widespread in the Campania region and Ferrovia variety, marketed in Italy and abroad. The major sugar and organic acid constituents, anthocyanin composition, colour (CIE L*, a*, b*), firmness, volatile neo-formation compounds (acetaldehyde, ethanol and methanol) and sensory attributes were determined at harvest and after 15 days of fruit storage at 1 degreesC and 95% RH. The ANOVA and PCA plots showed that both cherry varieties and storage conditions affected sensory/chemical quality but the variation caused by cool storage seem…
Study of chemical changes produced in virgin olive oils with different phenolic contents during an accelerated storage treatment.
2009
Chemical changes produced in an extra virgin olive oil sample in the presence (EVOO) and absence (EVOOP) of its phenolic fraction during an accelerated storage treatment at 60 degrees C up to 7 weeks were studied. Modifications in phenol content, as well as changes in several quality parameters (free acidity, peroxide value, UV absorbance, fatty acid composition, oxidative stability index, and tocopherol content) were also evaluated under the same storage conditions and compared to those of the same sample deprived of phenolic compounds. When the phenolic extract of the EVOO was studied, a decrease of the antioxidants first present in the sample and an increase of the oxidized products were…
Freshman Engineering’ Reasoning Strategies When Answering FCI Questions: A Case Study
2020
Force Concept Inventory (FCI) is a questionnaire commonly used to assess students’ conceptual understanding of Newtonian Mechanics. We show that Cluster Analysis methods can be used to study student answers to FCI by finding their reasoning strategies on Newtonian Mechanics. Our analysis is performed to data obtained by a sample of freshman engineering students just at the beginning of their first General Physics course. The analysis takes into account the decomposition of the force concept into the conceptual dimensions suggested by test authors and successive researches. We identified groups of students with similar answering strategies, characterised by correct answers, as well as by non…
On the Internationalization of Corporate Boards
2013
Despite the global reach of their commercial activities, many multinational firms have proved slow in internationalizing their boards of directors. Based on a panel study of the internationalization of the boards of 347 non-financial firms from the Nordic countries, we find a higher fraction of international board membership in firms with more foreign sales, in firms with more foreign ownership and in firms whose shares are traded on foreign (mostly European) stock exchanges. Moreover, we find international directors and national directors with international experience complementary. The first-mentioned group is found to serve a monitoring role, related to financial internationalization of …
Effects of heavy metals on soil microflora
2000
Elevated concentrations of heavy metals are known to cause disturbances in all living organisms. A reduction in the activity of forest microbes, expressed as decreased carbon and nitrogen mineralisation, may result in a slower rate of litter decomposition and slower nutrient cycling in the whole ecosystem (Baath 1989). In areas severely polluted by heavy metals, this can be seen as an accumulation of undecomposed litter on the forest floor. Thus, in addition to the direct toxicity of heavy metals, the trees may suffer from nutrient deficiency resulting from the decrease in the mineralisation of nutrients from the litter. Heavy metals can also retard litter decomposition processes in less po…
Inside Back Cover: Boron Nitride‐supported Sub‐nanometer Pd 6 Clusters for Formic Acid Decomposition: A DFT Study (ChemCatChem 9/2017)
2017
Generation of monosubstituted o-benzynes from polymeric reagents via heterolytic fragmentations
1984
Abstract Generation of four 4-substituted o-benzynes by heterolytic — fragmentation reactions is demonstrated.
A new Frequency Domain Measure of Causality based on Partial Spectral Decomposition of Autoregressive Processes and its Application to Cardiovascular…
2019
We present a new method to quantify in the frequency domain the strength of directed interactions between linear stochastic processes. This issue is traditionally addressed by the directed coherence (DC), a popular causality measure derived from the spectral representation of vector autoregressive (AR) processes. Here, to overcome intrinsic limitations of the DC when it needs to be objectively quantified within specific frequency bands, we propose an approach based on spectral decomposition, which allows to isolate oscillatory components related to the pole representation of the vector AR process in the Z-domain. Relating the causal and non-causal power content of these components we obtain…
Chemical-physical and nutritional characteristics of mature-green and mature-ripe ‘Kensington Pride’ mango fruit cultivated in Mediterranean area dur…
2017
Introduction - Mango is a very short postharvest life climacteric fruit. Mangoes are usually harvested firm and green because they are often assigned to long transportation before reaching the market, or they are collected after color break for local markets. In both cases, temperature control is the most critical factor in fruit ripening management. The aim of this study was to investigate the quality evolution of mature-green and mature-ripe mango fruit submitted to 8°C and 90 ± 5% of relative humidity to assess the possibility to prolong its postharvest life. Materials and methods - The fruit of mango (Mangifera indica L. cv. Kensington Pride) grown in a Mediterranean environment was s…