8 research outputs found
Electrodeposition of Nb and Al from chloroaluminate melt on vitreous carbon
Niobium and aluminium were electrodeposited at 200 Ā°C under argon
atmosphere onto vitreous carbon from inorganic chloroaluminate melts (AlCl3+NaCl)
with added niobium. Niobium was introduced into the electrolyte by anodic dissolution
of metallic niobium or by chemical dissolution of Nb2O5 in a melt of equimolar
AlCl3+NaCl mixture. The processes of deposition/dissolution onto/from vitreous carbon
were investigated by cyclic voltammetry and chronoamperometry. Characterization of
the obtained deposits was done by Scanning Electron Microscopy (SEM) and Energy
Dispersive Spectroscopy (EDS). The only observed reduction processes on the working
electrode in the potential window from 1.000 V to ā 1.000 V vs. Al, were individual
niobium deposition and codeposition of niobium and aluminium with Al-Nb alloys
formation.
Electrodeposition of niobium from the chloroaluminate melt with added niobium
(V) oxide seems to start at around ā 0.100 V vs. Al and at about ā 0.200 V vs. Al
aluminium starts codepositing. During the codeposition Nb-Al alloys were formed.
Niobium deposition starting potential from the electrolyte with niobium added by
anodic dissolution starts at 0.100 V vs. Al, and aluminium codeposition starting
potential was at around ā 0.025 V vs. Al, followed by Nb/Al alloy formation
Electrodeposition of Nb and Al from chloroaluminate melt on vitreous carbon
Niobium and aluminium were electrodeposited at 200 Ā°C under argon atmosphere onto vitreous carbon from inorganic chloroaluminate melts (AlCl3+NaCl) with added niobium. Niobium was introduced into the electrolyte by anodic dissolution of metallic niobium or by chemical dissolution of Nb2O5 in a melt of equimolar AlCl3+NaCl mixture. The processes of deposition/dissolution onto/from vitreous carbon were investigated by cyclic voltammetry and chronoamperometry. Characterization of the obtained deposits was done by Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS). The only observed reduction processes on the working electrode in the potential window from 1.000 V to ā 1.000 V vs. Al, were individual niobium deposition and codeposition of niobium and aluminium with Al-Nb alloys formation. Electrodeposition of niobium from the chloroaluminate melt with added niobium (V) oxide seems to start at around ā 0.100 V vs. Al and at about ā 0.200 V vs. Al aluminium starts codepositing. During the codeposition Nb-Al alloys were formed. Niobium deposition starting potential from the electrolyte with niobium added by anodic dissolution starts at 0.100 V vs. Al, and aluminium codeposition starting potential was at around ā 0.025 V vs. Al, followed by Nb/Al alloy formation
Breast dynamic contrast enhanced MRI: fibrocystic changes presenting as a non-mass enhancement mimicking malignancy
We aimed to analyse the morphokinetic features of breast fibrocystic changes (nonproliferative lesions, proliferative lesions without atypia and proliferative lesions with atypia) presenting as a non-mass enhancement (NME)in dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) examination. Forty-six patients with histologically proven fibrocystic changes (FCCs) were retrospectively reviewed, according to Breast Imaging Reporting and Data System (BI-RADS) lexicon. Prior to DCE-MRI examination, a unilateral breast lesion suspicious of malignancy was detected clinically, on mammography or breast ultrasonography. The predominant features of FCCs presenting as NME in DCE-MRI examination were: unilateral regional or diffuse distribution (in 35 patients or 76.1%), heterogeneous or clumped internal pattern of enhancement (in 36 patients or 78.3%), plateau time-intensity curve (in 25 patients or 54.3%), moderate or fast wash-in (in 31 patients or 67.4%).Nonproliferative lesions were found in 11 patients (24%), proliferative lesions without atypia in 29 patients (63%) and lesions with atypia in six patients (13%), without statistically significant difference of morphokinetic features, except of the association of clustered microcysts with proliferative dysplasia without atypia. FCCs presenting as NME in DCE-MRI examination have several morphokinetic features suspicious of malignancy, therefore requiring biopsy (BI-RADS 4). Nonproliferative lesions, proliferative lesions without atypia and proliferative lesions with atypia predominantly share the same predefined DCE-MRI morphokinetic features.Radiology and Oncology (2017), 51(2): 130-13
Far infrared and transport properties of single crystal PBTE samples doped with Ce
Single crystal samples of lead telluride doped with cerium were made using the Bridgman technique. Single crystals could be easily cleaved parallel to the (002) plane. Room temperature far infrared reflectivity was measured on single crystal samples and a plasma minimum at about 180 cm(-1) and local modes of Ce were observed. A fitting procedure based on a modified four parameter model of plasmon - phonon interaction, was used to determine the values of optical parameters. Carrier concentration and their mobility were measured at room and liquid nitrogen temperatures.Romanian Conference on Advanced Materials (ROCAM 2000), Bucharest, ROMANIA, october 23-25th, 2000
Isolation, selection and adaptation of zymogenous microorganisms: a basis of successful bioremediation
The paper presents the results of ex-situ bioremediation of soil on a pilot heap (halde) within the grounds of Petroleum Refinery PanÄevo, Serbia