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61.
Illicit drugs, a novel group of environmental contaminants 总被引:1,自引:0,他引:1
Zuccato E Castiglioni S Bagnati R Chiabrando C Grassi P Fanelli R 《Water research》2008,42(4-5):961-968
It is now well established that residues from therapeutic drugs consumed by humans can end up, through the sewage system, in the surface water of populated areas. Given that the global production of major illicit drugs is comparable to that of widely used pharmaceuticals, we tested for the presence of drugs of abuse (cocaine, opioids, amphetamines and cannabis derivatives), some related opioid pharmaceuticals (codeine and methadone) and/or their metabolites in Italian and British surface waters. Having identified residues of all major drugs of abuse in raw and treated urban wastewater, we now measured their levels in several rivers and lakes by a selective multi-residue assay based on liquid chromatography-tandem mass spectrometry. Recoveries in surface water were generally higher than 80%, with overall variability of the method lower than 10%. LODs were generally lower than 0.2 ng/L, and LOQs were lower than 0.6 ng/L, with few exceptions. Many of the tested substances were found in both rivers and lakes, at concentrations ranging from high pg/L to high ng/L, with loads in rivers in the range of tenths to hundreds of grams per day. Our data indicate that residues of drugs of abuse have become widespread surface water contaminants in populated areas. Since most of these residues still have potent pharmacological activities, their presence in the aquatic environment may have potential implications for human health and wildlife. 相似文献
62.
Over the decades there have been several papers on the coloration of cotton-based textiles. The number of articles dealing with the processing of cotton, including preparation, dyeing, and finishing, may be in the thousands. An investigation of the possible causes of problems occurring in the coloration of textiles revealed that a comprehensive review of case studies and scientific analysis would be a welcome addition to the already rich pool of knowledge in this area. 相似文献
63.
Marco Di Renzo Fabio Graziosi Riccardo Minutolo Mauro Montanari Fortunato Santucci 《Mobile Networks and Applications》2006,11(4):451-467
This paper proposes an investigation of the propagation behaviour for Ultra-Wide Bandwidth (UWB) signals in outdoor environments.
Specifically, we first report on the results of an extensive measurement campaign carried out in three selected scenarios,
namely “forest”, “hilly” and “sub-urban” environments. Then, we present the statistical model derived through the post-processing
of collected samples by the CLEAN algorithm. While an extensive collection of results is provided in the paper, the main achievements
can be summarized as follows: (i) the path-loss exponent varies from 2 to 3.5 and depends on the reference scenario and on
the height of transmission and reception equipments with respect to the ground floor, (ii) the local mean of the received
power experiences a Log-Normal shadowing with a standard deviation that may depend on the azimuth position, (iii) the statistics
of the first received echo in the small-scale analysis also well fit a Log-Normal distribution; (iv) the delay spread in the
small-scale multipath scenario turns out to be quite small (i.e. roughly 10 ns in the forest scenario and less than 32 ns
in the sub-urban scenario).
Marco Di Renzo (S’05) received the laurea degree (cum laude) in Electronic Engineering from the University of L’Aquila, Italy, in 2003. In 2002 he was with the Center of Excellence
in Research DEWS (Design Methodologies for Embedded Controllers, Wireless Interconnections and System–on-Chip) at the Department
of Electrical Engineering, University of L’Aquila, doing research on the analysis and design of Ultra Wide Band digital receiver
architectures. Since 2003 he has been with the Department of Electrical Engineering, University of L’Aquila, where he worked
on channel sounding and modelling for Ultra Wide Band systems and where he is currently pursuing his Ph.D. degree in Electric
and Information Engineering. His current research activity is focused on channel modelling, synchronization and detection
theory with specific interest to the Ultra Wide Band technology. In 2004 he played a key role in the successful creation of
WEST Aquila S.r.l. (Wireless Embedded Systems Technologies Aquila), a R&D Spin-Off of the University of L’Aquila and the Center
of Excellence in Research DEWS, where he currently holds the position of research engineer.
Fabio Graziosi (S’96–M’97) was born in L’Aquila, Italy, in 1968. He received the Laurea degree (cum laude) and Ph.D. degree in electronic engineering from the University of L’Aquila, L’Aquila, Italy, in 1993 and 1997, respectively.
Since February 1997 he has been with the Department of Electrical Engineering, at the University of L’Aquila, where he currently
holds the position of Associate Professor. His current research interests are mainly focused on wireless communication systems
with emphasis on wireless sensor networks and ultra wide band communication techniques. He is involved in major national and
European research projects in the field of wireless systems. He is member of the Executive Committee of the Center of Excellence
DEWS and serves as Chairman of the Board of Directors of WEST Aquila S.r.l., a Spin-off R&D Company of the University of L’Aquila
and Center of Excellence DEWS, founded in December 2004.
Riccardo Minutolo works in Thales Italia in the R&D department. He graduated in Electronic Engineering in the University of L’Aquila, in 1999.
He joined Thomson-csf in 1999 working as junior engineer in the Radio propagation, interference and software development.
In that period he gained expertise in HF, VHF, UHF, SHF radio propagation. In 2002 he joined Thales Italy (ex-Thomson-csf)
working in the ad hoc networking area. In 2002 he was the National coordinator of a 3 years European international project
(Euclide UWB). The Euclide UWB project aimed to study and research the potentiality of the emerging UWB technology for civil
security and military purposes. Since 2002 his major areas of interest are: radio propagation, UWB physical layer, MAC and
networking.
Mauro Montanari was born in 1950 in Rimini and graduated in Electronic Engineering at Bologna University in 1974. He joined in 1976 Telettra,
a national telecommunication company, working since the beginning in Defence R&D activities. His first experience was in the
field of advanced automatic antenna matching unit in HF band. Afterwards he mastered, staying for several time periods in
TRW—Redondo Beach/California, the technical issue of protecting radio communications through Spread Spectrum communications
systems, in view of an important application to a new generation of tactical radio systems in VHF frequency band. On this
topic he is co-author, with Prof. S. Pupolin of Padua University, of the book “Spread Spectrum Communications Systems” Collana
Scientifica Telettra). From 1991 to 1998 he was responsible of the R&D Department within the Defence Division of Alcatel Italia
(formerly Telettra) and in this position he managed several R&D projects: (i) Triservice Digital Network for the Italian MOD,
in cooperation with Selenia Communications; (ii) SCRA (Single Channel Radio Access) and network management system for the
Italian Army tactical network (SOTRIN) as a partner of Catrin Consortium; (iii) A new generation of radio equipment in HF
band for fixed applications; (iv) High speed HF modem, according to several NATO waveforms; (v) HF fixed network for Italia
Ministry of Foreign Affairs; (vi) Wide band Interception and jamming systems in HF band. Since 1999, he is responsible, within
Thales Italia SpA—Land and Joint Systems Division, of Advanced Studies area with the task of promoting in the company new
emerging technologies, specifically in the field of Wireless LAN, Tactical Internet, sensor networks, Ultra Wide Band for
military applications and plasma antennas. This role includes establishing relations with most Thales R&D centres located
in Europe and promoting new cooperative activities in new advanced technological areas. He also manages scientific relation
with several Italian Universities.
Fortunato Santucci (S’93–M’95–SM’00) was born at L’Aquila, Italy, in 1964. He received the laurea degree and the Ph.D. degree in Electronic
Engineering from the University of L’Aquila, Italy, in 1989 and 1994, respectively. In 1989 he was with Selenia Spazio S.p.a.,
Rome, working on VSAT networks design. In 1991–1992 he was at the Solid State Electronics Institute (I.E.S.S.) of the National
Research Council (C.N.R.), Rome, doing research on superconductor receivers for millimeter wave satellite systems. Since 1994
he has been with the Department of Electrical Engineering, University of L’Aquila, where he currently holds the position of
Associate Professor. In 1996 he was a visiting researcher at the Department of Electrical and Computer Engineering of the
University of Victoria, BC, Canada, where he researched on CDMA networks. His current research activity is focused on communication
theory, access control and radio resource management in wireless systems, with special emphasis on technologies for networked
embedded systems. He has participated in major national and European research programs in wireless mobile communications and
coordinates research programs funded by industrial partners. He has been a reviewer for major technical journal in telecommunications
and a session chairman in various conferences. He currently serves as an Editor for the IEEE Transactions on Communications
and Kluwer Telecommunications Systems. He has been/is in the TPC of several conferences in communications. He is a Senior
Member of the IEEE and is a member of the Communications Theory Committee. He is in the Executive Committee of the Center
of Excellence DEWS at the University of L’Aquila and in the Executive Committee of CNIT. 相似文献
64.
Computational Fluid Dynamics (CFD) modelling has been used to simulate a liquid fluidized bed of lead shot in slugging mode. Simulations have been performed using a commercial code, CFX4.4. The kinetic model for granular flow, which is already available in CFX, has been used during this study. 2D time-dependent simulations have been carried out at different water velocities. Simulated aspects of fluidization such as voidage profiles, slug formation, pressure drop and pressure fluctuations have been analysed. The fluid-bed pressure drop was found to be greater than the theoretical one at all velocities, in agreement with experimental observations reported for fully slugging fluidized beds. Power spectral density analysis of the pressure signal was used to investigate the development of the flow pattern and the structure of the fluid-bed with increasing fluidizing velocity. A comparison between experimental and simulated results is also reported. 相似文献
65.
66.
P Maggiora S Marchio MC Stella M Giai A Belfiore M De Bortoli MF Di Renzo A Costantino P Sismondi PM Comoglio 《Canadian Metallurgical Quarterly》1998,16(22):2927-2933
Constitutive activation of the RON gene, known to code for the tyrosine-kinase receptor for Macrophage Stimulating Protein (also known as Scatter Factor 2), has been shown to induce invasive-metastatic phenotype in vitro. As yet, nothing is known about the expression of this novel member of the MET-oncogene family in spontaneously occurring human cancers. Here we report that Ron is expressed at abnormally high levels in about 50% primary breast carcinomas (35/74 patients). Among these, the expression is increased more than 20-fold in 12 cases and the overexpressed protein is constitutively phosphorylated on tyrosine residues. Notably, Ron is only barely detectable in epithelial cells of the mammary gland, and its expression remains unchanged in benign breast lesions (including adenomas and papillomas). Overexpression was observed in different histotypic variants of carcinomas; it is associated with the disease at any stage and correlates with the post-menopausal status. In breast carcinoma cells grown in vitro, activation of the Ron receptor resulted in proliferation, migration and invasion through reconstituted basement membranes. Altogether, these data suggest a role for the RON gene in progression of human breast carcinomas to the invasive-metastatic phenotype. 相似文献
67.
Synthesis of multiwall carbon nanotubes by electric arc discharge in liquid environments 总被引:1,自引:0,他引:1
This work reports the experimental results from the production of multiwall carbon nanotubes (MWCN) synthesized by an electric arc discharge performed in liquid environments between pure graphite electrodes. Both liquid nitrogen and deionised water were suitable for a successful synthesis of this form of carbon aggregation. We report a successful synthesis of MWCN by arc discharge submerged in deionised water. Electron microscopy observations of both the reaction products and the surface of the as-synthesized raw material showed the presence of structural degradation of the MWCN, which probably operates after their growth at the cathode. The degradation is tentatively ascribed to a combination of overheating and high current density experienced by the as-synthesized MWNT, which can be caused by the loose structure of the as-deposited material. The damage appeared to be less severe in water environments, probably owing to the better cooling capacity of water relative to liquid nitrogen. 相似文献
68.
A. M. Gaddis Rex Ellis Jennie Shamey G. T. Currie 《Journal of the American Oil Chemists' Society》1965,42(7):620-624
Comparison of quantitative methods for the isolation of aldehydes from lard oxidized at 23C showed an extreme sensitivity
of precursors to isolation conditions. Differences existed in the quantity and class compositions of the monocarbonyl compounds
isolated. Acid conditions caused considerable breakdown of alkanal and alk-2-enal precursors. Steam distillation (100C) released
alkanals, alk-2-enals, and alk-2,4-dienals. The mild Girard T method apparently produced a small amt of alk-2-enals from precursors,
but except in the initial stages isolated the lowest amounts of aldehydes. Complete evaluation of the method for isolation
of free aldehydes was not possible because alkanals were released from precursors during the vacuum distillation procedure
(50C). The Schwartz (dilute phosphoric acid), Girard T, and vacuum distillation methods isolated similar amounts of alk-2,4-dienals.
Curious changes in relationships, possibly indicative of oxidation stages, were observed as autoxidation progressed. 相似文献
69.
70.
Grappa quality from the Chianti and Montepulciano areas (Tuscany,Italy): monitoring the leaching of copper from distillation columns 下载免费PDF全文
Gabriella Tamasi Alessandro Donati Gemma Leone Agnese Magnani Renzo Cini Eugenio Macchia Claudio Rossi Claudia Bonechi 《International Journal of Food Science & Technology》2018,53(6):1558-1565
The main aim of this work was to evaluate the leaching of copper in grappa from distillation plant that treats Cabernet and Sangiovese marcs (Montepulciano and Chianti, Tuscany). Copper content (determined by atomic absorption spectrometry, AAS) was 1.05 ± 0.03 mg L?1 in industrial distillates (Cabernet marc, 82.3% alcohol, v/v), and 3.7 ± 0.2 μg L?1 in artificial grappa (62.0%, Cabernet) obtained by distilling marc in a laboratory‐scale glassware plant. The artificial grappa distillate was refluxed over copper shavings, and copper content, CCu, was analysed in relation to reflux time and wear of the copper bell. The results showed that CCu trend was almost linear with increasing alcohol concentration and constant reflux time, and vice versa. The ratios of selected volatile components were not influenced by reflux on the shavings. 相似文献