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2.
Evaluation of the effect of processing on cocoa polyphenols: antiradical activity,anthocyanins and procyanidins profiling from raw beans to chocolate 下载免费PDF全文
Matteo Bordiga Monica Locatelli Fabiano Travaglia Jean Daniel Coïsson Giuseppe Mazza Marco Arlorio 《International Journal of Food Science & Technology》2015,50(3):840-848
The content and composition of anthocyanins and procyanidins in fermented cocoa beans (from different geographic origins: Ecuador, Cameroon, Ivory Coast, Ghana and Nigeria), roasted nibs, cocoa mass and chocolate were determined, beside the determination of the total antiradical capacity. Concerning geographic origin, cocoa beans and processed products from Ecuador showed the highest levels of anthocyanins, followed by Nigeria and Cameroon. Generally, as cocoa beans were further processed, the levels of anthocyanins and flavan‐3‐ols decreased. The largest observed losses of phenolics occurred during roasting. A progressive decreasing trend in polyphenol concentration was observed in the other processed samples as well. Despite the original content of polyphenols in raw cocoa beans, technological processes imply a significant impact on cocoa quality, confirming the need of specific optimisation to obtain high value chocolate. 相似文献
3.
M. F. Sorokïna O. M. Kanunnikova F. Z. Gil'mutdinov V. I. Kozhevnikov 《Glass and Ceramics》1996,53(1-2):11-13
The method of x-ray electron spectroscopy is used to investigate lead silicatexPbO(1 -x) · SiO2 (x - 0.3, 0.4, 0.5, 0.55, 0.667) glasses. The concentration dependences of the spectra of inner Pb4f, Si2p, and Ols levels led to the conclusion that for low contents of PbO, lead is present in the glass in the form of modifying ions, whereas in high concentrations, it plays the role of glass former. Restructuring in the glass occurs for about 50% molar concentration of PbO. The Pb - O bond in the glass is more ionic than in PbO. With an increase in the PbO content in the glass, the Pb - O bond becomes closer to that of lead monoxide, i.e., is more covalent. 相似文献
4.
Nguyen-Huy Dung Pardo Marie-Paule Dogguy.Smiri Leïla 《Materials Research Bulletin》1982,17(3):293-300
The Mn0.23Ga1.85S3 phase belongs to the solid solution , stable at low temperature in the Ga2S3MnS system. It is hexagonal superstructure of the wurtzite, with the Ga2S3α′ type (; Z = 6; space groupe P61 or P65). Its crystal structure has been refined by the least squares method to a final R = 0.06 with 323 independant reflections. This structure is closely related to Ga2S3 α described by Hahn and Frank, and differs only by the partial occupation of the vacant metal site of Ga2S3 by Mn atoms in statistical disorder. 相似文献
5.
In this paper we consider two performance modelling techniques from the perspectives of model construction, generation of
an underlying continuous time Markov process, and the potential for reduction in the Markov process. Such careful comparison
of modelling techniques allows us to appreciate the strengths and weaknesses of different approaches, and facilitates cross-fertilization
between them. In the present case we take a characteristic of one formalism, functional rates in Stochastic Automata Networks,
and introduce it to the other formalism, Performance Evaluation Process Algebra. We investigate the benefits of this cross-fertilization,
particularly from the perspectives of Markov process generation and reduction. 相似文献
6.
Adaptive filtering gives simple iterative methods for extracting a useful signal by linearly filtering an observation correlated with this useful signal. When the observation contains past values of the filter output—as is the case for a recursive structure— the adaptive filter is a non linear operator which can generate complex behaviours even though adaptation is a standard derivative of the gradient algorithm. Such behaviours are observed in a particular case : theArma adaptive prediction with a sinusoidal input. A slow adaptation speed involves a quasi-periodic behaviour due to the locally unstable character of the predictor. This phenomenon called selfstabilization persists as the adaptation speed increases. Its study is more complicated : the behaviour becomes chaotic. As an illustration, the digitization of telephone signals throughArma adaptive prediction shows the necessity of controlling the qualitative behaviour of the adaptive filtering solutions. 相似文献
7.
Amir Mohammadzadeh Pter P. Lakatos Mihly Balogh Ferenc Zdor Dvid rpd Kardi Zoltn S. Zdori Kornl Kirly Anna Rita Galambos Szilvia Barsi Pl Riba Sndor Benyhe Lszl Kles Tams Tbi va Szk Laszlo G. Harsing Jr. Mahmoud Al-Khrasani 《International journal of molecular sciences》2021,22(5)
The limited effect of current medications on neuropathic pain (NP) has initiated large efforts to develop effective treatments. Animal studies showed that glycine transporter (GlyT) inhibitors are promising analgesics in NP, though concerns regarding adverse effects were raised. We aimed to study NFPS and Org-25543, GlyT-1 and GlyT-2 inhibitors, respectively and their combination in rat mononeuropathic pain evoked by partial sciatic nerve ligation. Cerebrospinal fluid (CSF) glycine content was also determined by capillary electrophoresis. Subcutaneous (s.c.) 4 mg/kg NFPS or Org-25543 showed analgesia following acute administration (30–60 min). Small doses of each compound failed to produce antiallodynia up to 180 min after the acute administration. However, NFPS (1 mg/kg) produced antiallodynia after four days of treatment. Co-treatment with subanalgesic doses of NFPS (1 mg/kg) and Org-25543 (2 mg/kg) produced analgesia at 60 min and thereafter meanwhile increased significantly the CSF glycine content. This combination alleviated NP without affecting motor function. Test compounds failed to activate G-proteins in spinal cord. To the best of our knowledge for the first time we demonstrated augmented analgesia by combining GlyT-1 and 2 inhibitors. Increased CSF glycine content supports involvement of glycinergic system. Combining selective GlyT inhibitors or developing non-selective GlyT inhibitors might have therapeutic value in NP. 相似文献
8.
9.
The present work aims to provide a better understanding of the effect of both the proportions and the characteristics of slaked lime on the microstructure of a lime-cement-sand mortar. Cement (CPA CEM I 52.5) has been replaced by various categories of slaked lime chosen for the diversity of their physico-chemical characteristics.Cement has been replaced by lime in proportions varying between 0 to 10% of the total binder mass. With very few exceptions, mortars were produced by maintaining the quantity of water constant.Experimental results show that it is necessary to have a high lime substitution percentage to influence the microstructure of the mortar, except in the case of a lime containing magnesium hydroxide or calcic lime featuring sizeable specific surface area.The influence of the nature of the substituted lime on the development of the microstructure in the matrix has been examined by SEM observations of the mortar micro porosity. 相似文献
10.
During the preparation of alumina as a catalyst support from aluminium nitrates by precipitation with a NH4OH base, NO
2
⋅
radicals have been formed in the catalyst after calcination under air in the solid at different temperatures. These radicals
remained stable until a calcination temperature of 800°C. When the calcined catalyst was degassed under vacuum above 300 °C,
the NO
2
⋅
was reduced to give NO⋅ and O- species which were both tightly trapped in the solid. These latter species remained stable until vacuum treatment at 800
°C.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献