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11.
Solid mixtures containing ammonium perchlorate diluted with reputedly inert substances SiC, SiO2, TiO2, Al2O3 and the salts: KCl, NaCl, BaCO3, CaCO3 respectively were studied by TGA and DTA. Undiluted NH4ClO4 and the perchlorates of K, Na, Ba, Ca were also examined. The two known temperature regions of NH4 ClO4 thermolysis were confirmed. The first DTA exotherm of NH4ClO4 seems to be related to its limited decomposition; it can be suppressed by an ammonia atmosphere, by thermal cycles, or by heat-dissipating conditions. The second exotherm is related to the change of the decomposition mechanism of HClO4 above 330°. TGA rate curves of stoichiometric mixtures of NHClO4 with salts show two peaks due to decomposition of NH4ClO4 and one peak due to the MeClO4 formed on heating. The formation of MeClO4 is confirmed by visual observations and by DTA. Thermal cycles followed by DTA of stoichiometric mixtures of (NH4ClO4 + KCl), (NH4ClO4 + BaCO3) reveal the systematic formation of MeClO4 at the expense of NH4ClO4. For (NH4ClO4 + NaCl), (NH4ClO4 + CaCO3) there appear in the vicinity of the transition endotherm of NH4ClO4 new reversible endotherms difcontaining NH4ClO4. Only after their thermal decomposition do the transition endotherms of MeClO4 appear.  相似文献   
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Fully bio-based and biodegradable active films based on poly(lactic acid) (PLA) blended with poly(3-hydroxybutyrate) (PHB) and incorporating lactic acid oligomers (OLA) as plasticizers and carvacrol as active agent were extruded and fully characterized in their functional properties for antimicrobial active packaging. PLA_PHB films showed good barrier to water vapor, while the resistance to oxygen diffusion decreased with the addition of OLA and carvacrol. Their overall migration in aqueous food simulant was determined and no significant changes were observed by the addition of carvacrol and OLA to the PLA_PHB formulations. However, the effect of both additives in fatty food simulant can be considered a positive feature for the potential protection of foodstuff with high fat content. Moreover, the antioxidant and antimicrobial activities of the proposed formulations increased by the presence of carvacrol, with enhanced activity against Staphylococcus aureus if compared to Escherichia coli at short and long incubation times. These results underlined the specific antimicrobial properties of these bio-films suggesting their applicability in active food packaging.  相似文献   
14.
Despite suggestibility researchers' focus on adult behaviors that distort children's reports, whether behaviors examined in experimental work are used in the field is unknown. The current study presents a mutually exclusive and exhaustive hierarchical coding system that reflects interview questioning behaviors of concern in experimental work. The study examined 80 unstructured interviews conducted by 41 field interviewers with 40 children ages 3 to 7 about known events. Data on the use of leading and neutral questions are presented and include distinctions between accurate and inaccurate suggested information. In addition, analyses show that interviewers are consistent in their style of questioning and that a preinterview measure of interviewers' preference for a qualitative versus a quantitative interviewing style predicted the introduction of novel information into the interview. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
15.
Consumers are oriented towards fresh-cut vegetables that provide phytonutrients useful for preventing stress-related diseases. The aim of this work was to evaluate the cut operations on the quality changes of lamb's lettuce ( Valerianella olitoria L.) cv. Trofy during storage at 4 °C for 8 days. Results showed that chlorophyll and carotenoids reduction was observed after 8 days of storage. In both treatments, total carotenoids after 8 days decreased from 20 to 16 mg g−1 FW. Free and total phenols increased with storage in both treatments. Total phenols were 23% higher in control (32 μmol g−1 FW) compared to cut leaves (25 μmol g−1 FW) after 8 days of storage. Anthocyanins increased after 8 days and reached 30 mg 100 g−1 FW without significant difference between treatments. Ascorbic acid (AsA) and dehydroascorbic (DHA) acid increased in cut leaves compared to control. After 1 day AsA concentration was 3 300 nmol g−1 FW in cut leaves, while in control leaves was 1 500 nmol g−1 FW. Analogously AsA + DHA was higher in cut leaves, 4 100 nmol g−1 FW, while in control leaves the mean was 3 000 nmol g−1 FW. After 5 days of storage the values of AsA returned to initial values, while AsA + DHA were lower.  相似文献   
16.
The life cycle of schistosomes is reviewed in its various steps, both in permissive hosts (in which the cycle is completed) and in nonpermissive hosts (which excrete no viable eggs as a result of the infection). A large worm loss occurs at (or after) the lung stage in both types of hosts (normal attrition) and some nonpermissive hosts (like the rat) have an additional elimination of worms from the portal circulation. Worm growth and reproductive maturation are also impaired in several nonpermissive hosts and the possible host-parasite interactions leading to such limitations are discussed, with special reference to hormonal influences. Attention is also given to peculiar phenomena occurring in some hosts, like the late portal worm elimination in rhesus monkeys, the migration from mesenteric veins to lungs in rats, and the block to egg excretion in guinea pigs. The steps of the schistosome life cycle which appear vulnerable in several hosts are contrasted with the steps which are carried out successfully in the majority of hosts studied.  相似文献   
17.
Clean Technologies and Environmental Policy - In this mentioned article, the Author names are mistakenly have been replaced with the family name of the authors, and so the family names with the names.  相似文献   
18.
Scientometrics - In this paper, we analyze the structure of the article citation network of a particular subject obtained from the Web of Science (WoS) database. In specific, we modify a model...  相似文献   
19.
Epidemiological and intervention studies correlate anthocyanin-rich beverages and a low incidence of coronary heart diseases. Since endothelin-1 (ET-1) and nitric oxide (NO) produced by endothelial NO synthase (eNOS) are vascular tension regulators secreted by endothelial cells, we studied the influence of two anthocyanidins, namely cyanidin (CY) and delphinidin (DP), on the regulation of ET-1 and eNOS in cultured human umbilical vein endothelial cells (HUVECs). Aglycon anthocyanidin forms, such as CY and DP, may be present in vivo after the first deglycosylation step occurring in the jejunum and in the liver. DP showed a major action compared to CY inducing a significant dose-dependent inhibitory effect on both protein and mRNA levels of ET-1. CY and DP both increased the protein level of eNOS, but DP showed the major effect raising eNOS protein in a dose-dependent manner. To correlate the vasoprotective effect of CY and DP with their antioxidant activity, we analysed also the antioxidant effect of anthocyanidins both in vitro and in HUVECs. In particular, we examined the effect of anthocyanidins on endothelial heme oxygenase-1 (HO-1), an inducible stress protein. In all tests, DP showed a higher antioxidant activity than CY. Finally, the antiproliferative effect induced by DP was detected in HUVECs. DP and CY differ in the number and position of hydroxyl groups in their structure; therefore, the greater biological activity by DP, compared with CY, seems to be due to the presence of the three hydroxyl groups on the B ring in the molecular structure of DP.  相似文献   
20.
Metabolomic analysis by liquid chromatography-high-resolution mass spectrometry results in data sets with thousands of features arising from metabolites, fragments, isotopes, and adducts. Here we describe a software package, Metabolomic Analysis and Visualization ENgine (MAVEN), designed for efficient interactive analysis of LC-MS data, including in the presence of isotope labeling. The software contains tools for all aspects of the data analysis process, from feature extraction to pathway-based graphical data display. To facilitate data validation, a machine learning algorithm automatically assesses peak quality. Users interact with raw data primarily in the form of extracted ion chromatograms, which are displayed with overlaid circles indicating peak quality, and bar graphs of peak intensities for both unlabeled and isotope-labeled metabolite forms. Click-based navigation leads to additional information, such as raw data for specific isotopic forms or for metabolites changing significantly between conditions. Fast data processing algorithms result in nearly delay-free browsing. Drop-down menus provide tools for the overlay of data onto pathway maps. These tools enable animating series of pathway graphs, e.g., to show propagation of labeled forms through a metabolic network. MAVEN is released under an open source license at http://maven.princeton.edu.  相似文献   
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