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排序方式: 共有1158条查询结果,搜索用时 15 毫秒
141.
Gabriela Buda Lucian Dascalescu Adrian Samuila 《Particulate Science and Technology》2013,31(2):162-167
The control of the triboelectrification factors is the key for a successful application of electrostatic separation to the recycling of mixed plastics waste. This article focuses on the influence of material moisture on the tribocharging process of three granular materials: polyamide (PA), polyvinyl chloride (PVC), and polyethylene terephthalate (PET). Different values of moisture content were obtained by immersing the material in water or drying it in a laboratory oven. Afterward, the granular material was tribocharged on the tray of a vibratory feeder and the accumulated charge was measured by an electrometer. The maximum charge/mass ratio was obtained for the three plastic materials at different values of moisture content: 0.27% for PA, 0.12% for PET 0.1% for PVC. Series of 5 consecutive tribocharging experiments performed on the same sample, show that the first contributes with the greater amount of granules charge while the other four only slightly increment this value. The graphical representation of the evolution of the charge/mass ratio versus number of tribocharging experiment conducts to the conclusion that: i) the charge of the granules tends to saturate; ii) it is useless to excessively increase the duration of the tribocharging process. 相似文献
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144.
P Lanotte F Dubois S Le Pogam C Guerois B Fimbel Y Bacq Y Gruel A Goudeau F Barin 《Canadian Metallurgical Quarterly》1998,178(2):556-559
Several studies have reported the spontaneous loss of hepatitis C virus (HCV) antibodies in HCV-exposed persons. However, the relationship between seroreversion and spontaneous virus clearance has yet to be precisely determined in a single homogeneous population of untreated immunocompetent patients. In this study, 32 human immunodeficiency virus-seronegative hemophiliacs who had been exposed to HCV were followed for a mean duration of 141 months; 22 remained chronic carriers (68.8%). All but 1 of the nonviremic patients (90.0%) showed partial (8 cases) or complete (2 cases) seroreversion. In contrast, all but 1 of the viremic patients (95.1%) had a stable serologic profile when analyzed by a recombinant immunoblot assay. The results indicate that any HCV antibody-positive immunocompetent patient with no detectable serum HCV RNA and normal alanine aminotransferase values and whose serial samples show a progressive decrease in the level of HCV antibodies present may be considered as having a resolved infection. 相似文献
145.
Barrera-Díaz C Lugo-Lugo V Roa-Morales G Natividad R Martínez-Delgadillo SA 《Journal of hazardous materials》2011,185(2-3):1362-1368
In this study we present the cathodic Cr(VI) reduction using electrodissolution of iron anode. In batch experiments we tested four different cathodic materials; the best conditions were found when copper was used. It is observed that when more current is applied into the electrochemical cell faster reduction rates are achieved. Continuous experiments also reveal that Cr(VI) reduction could be done in a very efficient way. To confirm the experimental data, cyclic voltammetry was used and it was found that the cathodic Cr(VI) reduction is taking place. 相似文献
146.
Abstract: This paper proposes a method to enzymatically treat poor‐quality cocoa almonds (known as “slate”) to ensure the formation of chocolate flavor precursors. The production of flavor precursors improves the quality of these almonds, which are usually responsible for the low quality of the liquor produced. Proteases and carboxypeptidases from different sources were tested under various conditions. The different treatments were evaluated by chemical analysis (hydrolysis efficiency) and sensory analysis of the treated material compared to good‐quality cocoa almonds. The results show that it is possible, through the use of microbial enzymes, to generate the mixture of compounds that will release, after roasting, the characteristic chocolate flavor in poor‐quality almonds. However, it is necessary to optimize the conditions of enzymatic treatment to obtain better results and thus establish a process that can be used for industrial purposes for manufacturing cocoa and chocolate. Practical Application: The basidiomycete Moniliophtora perniciosa is the causative agent of witches’ broom disease (WBD) of the cocoa tree, whose seeds are the source of chocolate. It is the most important phytopathological problem of cocoa‐producing areas of the American continent, and has decimated the Brazilian cocoa industry. In Bahia (Brazil), M. perniciosa was identified in 1989 and, as a consequence of its spreading, the annual production of cocoa almonds dropped from 450000 to 90000 tons within 12 y, reducing export values from an all‐time high of about US$ 1 billion to 110 million. The high incidence of WBD incapacitates Brazil to produce enough cocoa almonds even for the internal market, leading the country to import low‐quality cocoa almonds mainly from African countries. Our work proposes an enzymatic treatment to increase the quality of that cocoa almonds and, consequently, to improve the quality of the chocolate produced and consumed in the country. 相似文献
147.
Silvia Mironeasa Georgiana Gabriela Codină Costel Mironeasa 《International Journal of Food Properties》2016,19(4):859-872
In this work, the response surface methodology was used to determine the optimum level of input variables, gluten deformation index (mm) and the level of grape seed flour (%) addition in wheat flour that improve falling number index and Mixolab dough rheological parameters. The full factorial model was the best compatible model which fitted to each response. A replacement dose of 4.08% in wheat flour with gluten deformation index value of 8.27 mm was found optimal. The influence of optimum values of variables on dough microstructure has been investigated using epifluorescence light microscopy. 相似文献
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Cosmin Vasilica Pricope Bogdan Ionel Tamba Gabriela Dumitrita Stanciu Magdalena Cuciureanu Anca Narcisa Neagu Ioana Creanga-Murariu Bogdan-Ionut Dobrovat Cristina Mariana Uritu Silviu Iulian Filipiuc Bianca-Mariana Pricope Teodora Alexa-Stratulat 《International journal of molecular sciences》2022,23(21)
Chronic neuropathic pain (CNP) affects around 10% of the general population and has a significant social, emotional, and economic impact. Current diagnosis techniques rely mainly on patient-reported outcomes and symptoms, which leads to significant diagnostic heterogeneity and subsequent challenges in management and assessment of outcomes. As such, it is necessary to review the approach to a pathology that occurs so frequently, with such burdensome and complex implications. Recent research has shown that imaging methods can detect subtle neuroplastic changes in the central and peripheral nervous system, which can be correlated with neuropathic symptoms and may serve as potential markers. The aim of this paper is to review available imaging methods used for diagnosing and assessing therapeutic efficacy in CNP for both the preclinical and clinical setting. Of course, further research is required to standardize and improve detection accuracy, but available data indicate that imaging is a valuable tool that can impact the management of CNP. 相似文献
150.
Elena Manaila Gabriela Craciun Ion Cosmin Calina 《International journal of molecular sciences》2023,24(1)
Being both a cause and a victim of water scarcity and nutrient deficiency, agriculture as a sustainable livelihood is dependent now on finding new suport solutions. Biodegradable hydrogels usage as soil conditioners may be one of the most effective solutions for irrigation efficiency improvement, reducing the quantity of soluble fertilizers per crop cycle and combating pathogens, due to their versatility assured by both obtaining method and properties. The first goal of the work was the obtaining by electron beam irradiation and characterization of some Sodium Alginate-g-acrylamide/acrylic Acid hydrogels, the second one being the investigation of their potential use as a soil conditioner by successive experiments of absorption and release of two different aqueous nutrient solutions. Alginate-g-acrylamide/acrylic Acid hydrogels were obtained by electron beam irradiation using the linear accelerator ALID 7 at 5.5 MeV at the irradiation doses of 5 and 6 kGy. For this were prepared monomeric solutions that contained 1 and 2% sodium alginate, acrylamide and acrylic acid in ratios of 1:1 and 1.5:1, respectively, for the obtaining of materials with hybrid properties derived from natural and synthetic components. Physical, chemical, structural and morphological characteristics of the obtained hydrogels were investigated by specific analysis using swelling, diffusion and network studies and Fourier Transform Infrared Spectroscopy and Scanning Electron Microscopy. Four successive absorption and release experiments of some synthetic and natural aqueous solutions with nutrients were performed. 相似文献