Search results for "process"

Synthesis of oxide-supported vanadium catalysts and their activity in ethylene polymerization

1999

The activity of oxide-supported vanadium-based catalyst systems (VOCl 3/Et 2AlCl) in low-pressure ethylene polymerization and the properties of the resulting polyethylenes were studied in relation to the type and mode of modification of the oxide support. Alumina, silica and an un"conventional silica-type material prepared by the sol-gel process were used as supports. Results are compared with those obtained earlier with a catalyst supported on MgCl 2(THF) 2. Of the oxides studied, the silica-type sol-gel material dehydrated and subsequently modified with Et 2AlCl proved to be the best carrier for a vanadium catalyst. The polyethylene prepared by using this catalyst support was found to exh…

Physical and chemical interactions involved in several flavour compounds/food matrix systems

2002

National audience; Food-matrix components, such as proteins, polysaccharides, and lipids interact with flavour compounds in different ways. Proteins bind flavour compounds mostly by hydrophobic interactions and possible hydrogen bonding, as illustrated by molecular visualisation. Addition of fat induces a great retention of hydrophobic compounds, which depend on the nature of fat, degree of unsaturation, hydrophobic chain length of fatty acids. Addition of hydrocolloids modifies the release of hydrophobic aroma compounds, due to a lower diffusion in the matrix. In jellified systems, gel structure not only affects partition coefficients but also mass transfer coefficients of flavour compound…

ZINGARI, CHE STRANO POPOLO! STORIA E PROBLEMI DI UNA MINORANZA ESCLUSA

2007

Uno strumento di riflessione per comprendere ed analizzare le ragioni che rendono oggettivamente difficile il rapporto con la popolazione rom. Il contributo contenuto in questo volume analizza le ragioni storiche e sociali che hanno prodotto - e che continuano a produrre - fenomeni di marginalizzazione.

The Hamburg/ESO R-process Enhanced Star survey (HERES)

2004

We report on a dedicated effort to identify and study metal-poor stars strongly enhanced in r-process elements ([r/Fe] > 1 dex; hereafter r-II stars), the Hamburg/ESO R-process Enhanced Star survey (HERES). Moderate-resolution (~2A) follow-up spectroscopy has been obtained for metal-poor giant candidates selected from the Hamburg/ESO objective-prism survey (HES) as well as the HK survey to identify sharp-lined stars with [Fe/H] < -2.5dex. For several hundred confirmed metal-poor giants brighter than B~16.5mag (most of them from the HES), ``snapshot'' spectra (R~20,000; S/N~30 per pixel) are being obtained with VLT/UVES, with the main aim of finding the 2-3% r-II stars expected to be a…

Selective Laser Sintering of Metal-Organic Frameworks: Production of Highly Porous Filters by 3D Printing onto a Polymeric Matrix.

2019

Metal‐organic frameworks (MOFs) have raised a lot of interest, especially as adsorbing materials, because of their unique and well‐defined pore structures. One of the main challenges in the utilization of MOFs is their crystalline and powdery nature, which makes their use inconvenient in practice. Three‐dimensional printing has been suggested as a potential solution to overcome this problem. We used selective laser sintering (SLS) to print highly porous flow‐through filters containing the MOF copper(II) benzene‐1,3,5‐tricarboxylate (HKUST‐1). These filters were printed simply by mixing HKUST‐1 with an easily printable nylon‐12 polymer matrix. By using the SLS, powdery particles were fused t…

A low road to investment and labour management? : the labour process at Nordic subsidiaries in the Baltic States

2009

From the Metropolitan Areas to the Post-metropolitan Dimension

2021

This chapter introduces a description of the two main areas that will be discussed throughout the book: the metropolitan region of Palermo and South-Eastern Sicily. The chapter starts with a socio-economic analysis describing the characteristics of demography, employment and income in these two parts of Sicily, by comparing them to the situation of other areas in Italy. A spatial analysis of housing and land use complements the socio-economic outlook. Each section describes the most consolidated trends in these areas, but also discusses the most innovative changes and the challenges Sicily has been facing over the years.

Transcranial Magnetic Stimulation Trains at 1 Hz Frequency of the Right Posterior Parietal Cortex Facilitate Recognition Memory

2021

Neuroimaging, neuropsychological, and brain stimulation studies have led to contrasting findings regarding the potential roles of the lateral parietal lobe in episodic memory. Studies using brain stimulation methods reported in the literature do not offer unequivocal findings on the interactions with stimulation location (left vs. right hemisphere) or timing of the stimulation (encoding vs. retrieval). To address these issues, active and sham 1 Hz repetitive transcranial magnetic stimulation (rTMS) trains of 600 stimuli were applied over the right or left posterior parietal cortex (PPC) before the encoding or before the retrieval phase of a recognition memory task of unknown faces in a grou…

Blends using brabender farinograph and E6 Haubelt flourgraph

2010

The aim of this work is to establish correlations between the values of the Brabender Farinograph and the E6 Haubert Flourgraph. We analyzed two types of flours, white flour with additives (WF add) and brown flour with additives (BF add). The following parameters were varied: water absorption capacity, development time, the stability, the degree of softening and the quality number of wheat and potato flour mixture. A statistical analysis was made from linear regression equations. The obtained values for the E6 Flourgraph are comparable with Farinograph values and units. Hydration capacity values, calculated for a standard consistency of 500 HE, UF, obtained on these two devices are in a clo…

Protein recovery as a resource from waste specifically via membrane technology : from waste to wonder

2021

Economic growth and the rapid increase in the world population has led to a greater need for natural resources, which in turn, has put pressure on said resources along with the environment. Water, food, and energy, among other resources, pose a huge challenge. Numerous essential resources, including organic substances and valuable nutrients, can be found in wastewater, and these could be recovered with efficient technologies. Protein recovery from waste streams can provide an alternative resource that could be utilized as animal feed. Membrane separation, adsorption, and microbe-assisted protein recovery have been proposed as technologies that could be used for the aforementioned protein re…