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The Romanian Seismic Network consisting of 8 short-period stations (S13), 60 Altus — K2 and Q330 seismic stations, is primarily designed to survey the Vrancea seismic region (strong and moderate Vrancea earthquakes). Since July 2002, a new seismic monitoring system, Bucovina Seismic Array (BURAR) has been operating. BURAR consists of 12 seismic stations distributed on a 5 km × 5 km area. 9 stations are equipped with short-period (SP) vertical sensors (GS-21 res) and one station is equipped with broad-band (BB) three component sensor (KS 54000). Broad-band sensors GMG40T (1000V/cm/s) were installed at 5 of the short-period stations, at the beginning of 2008. Recently, NIEP has developed its real-time digital seismic network. This network consists of 21 broad band stations and one seismic array. In the next year NIEP will install additional broad band stations in the central part of Romanian territory and other 40 strong motions stations in Bucharest.At the National Data Centre (NDC) runs BRTT’s Antelope™ 4.9 data acquisition and processing software on two HP workstations for real-time and post processing. The Antelope Real-Time System is also providing automatic event detection, arrival picking, event location and magnitude calculation.The Romanian Seismic Network is already linked with IRIS and ORFEUS organizations and other European countries via Internet and is contributing in near real time with waveform data from 5 broadband stations.The seismotectonic characteristics of the Vrancea region offer the opportunity to create and develop a rapid seismic warning system. This system allows warning in an approximately 25 seconds time window for Bucharest.

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Nowadays natural disasters phenomena as hurricanes, volcanic eruptions, tsunamis or earthquakes, are still difficult to prevent. Based on signaling of the phenomenon imminent appearance in the destructive area, important limitations in human losses and material damages will be carried out. For that  reason, WARNING turned into a key objective, both in theoretical and practical research.  For the earthquakes, warning intervals are nevertheless very short - seconds to maximum one minute (Mexico City case). Even if the time window is reduced, automated decision measures are possible to establish in case of an well organized system, mainly for: protection of dangerous chemical units and oil installations; shutdown valves of the natural gas pipelines to prevent fire hazard; protection of nuclear power plants and other high-risk nuclear objectives; electrical insulating of the power distribution network systems; alerting of emergency services, alerting of civil protection, and particularly of  civil population; protection of railway transportation systems etc.  In Romania, the major seismic risk zone is located in Vrancea region. The earthquakes occurring in this area are the main sources of the seismic hazard on the Romania territory.  Seismotectonic characteristics of the Vrancea region offered the opportunity to create and develop a rapid seismic warning system. This system is simple, reasonably low-priced and robust and allows warning in an approximately 25 seconds time window for Bucharest. Warning signal obtained will be issued at the responsible factors and specific users in order to control automated blocking of the installations and to carry out the required protection actions.

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Abstract  

Activation energies of ignition for the thermokinetic oscillations obtained during the heterogeneous catalytic oxidation of ethanol on Pd/Al2O3 in a dynamic calorimeter were obtained using the minimum values of the temperature oscillations. These activation energies of ignition are greater than the activation energies of the corresponding oscillations. The obtained results are discussed by assuming a PdOx redox cycle.

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Erythropoietin (EPO), a key hormone involved in red blood cell formation has been recently acknowledged for its pleiotropic actions and protective role in ageing and various pathological conditions concurrent with oxidative stress, vascular diseases and metabolic abnormalities such as diabetes mellitus. The aim of the study was to evaluate the relationship between circulating erythropoietin levels and oxidative stress biomarkers, in elderly with type 2 diabetes (T2DM). The study was carried out in 67 subjects with T2DM (69 ± 5 years; n = 37) without anemia, and aged-matched controls (70 ± 6 years; n = 30). EPO serum levels, erythrocyte susceptibility to lipid peroxidation (ESP) and total antioxidant capacity (TAC) were evaluated. Lower EPO levels (p < 0.01) and higher ESP values (p < 0.001) were found in T2DM group, compared to healthy subjects. EPO levels showed significant negative associations with ESP, both in T2DM subjects (r = −0.565; p < 0.001) and in all study population (r = –0,600; p < 0,001; n = 67). In conclusion, we provide new data regarding the cytoprotective effect of EPO exerted at systemic level on erythrocyte membrane, in the particular state of impaired glucose metabolism associated with oxidative stress, in the elderly.

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Journal of Thermal Analysis and Calorimetry
Authors:
M. Ştefănescu
,
M. Stoia
,
O. Ştefănescu
,
A. Popa
,
M. Simon
, and
C. Ionescu

Abstract  

Hybrid organic-inorganic materials, silica – polyols (ethylene-glycol – EG; 1,2 propane diol – 1,2PG; 1,3 propane diol – 1,3PG and glycerol – GL), were prepared by a sol-gel process starting from tetraethylorthosilicate (TEOS) and polyols, in acid catalysis. The resulting materials were studied by thermal analysis (in air and nitrogen), FTIR and solid state 29Si-NMR spectroscopy. These techniques evidenced the presence of polyols in the silica matrix both hydrogen bounded and chemically bounded in the silica network. The thermal analysis proves to be the most appropriate technique to evidence the organic chains linked in the matrix network and to follow the thermal evolution of the gels to the SiO2 matrix.

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Abstract

The in situ electrical properties and the catalytic activity of copper ferrite obtained by co-precipitation and thermal decomposition of polynuclear coordination compounds were studied in the propane oxidation reaction. The sample prepared by complexation had a better catalytic activity. Based on the conductivity data and the relative phase distribution in fresh and used compounds, the results are discussed in terms of the redox-type mechanism.

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Abstract

The electrical conductivity and the catalytic activity of SnO2 loaded TiO2 (anatase) particles were investigated in operando conditions. SnO2 depositions over commercial TiO2 samples (Sigma Aldrich and Rhone Poulenc) were obtained by the impregnation method. The samples were characterized by XRD, SEM/EDX and BET–N2 adsorption techniques. The AC electrical conductivity of the samples were measured between 25 and 400 °C under various atmospheres. The effect of the reactant mixture on the electrical conductivity and the catalytic performances of the samples were tested in propene oxidation. The results showed that the conductivity of SnO2/TiO2 samples depends strongly on the surface area of TiO2 support. The reducing effect of propene is more evident for higher surface area catalysts, these one showing also higher activity. On the other hand, the SnO2 deposition results in an increase of catalytic performances.

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Acta Biologica Hungarica
Authors:
Roxana Stan
,
Adriana Hangan
,
Lucia Dican
,
B. Sevastre
,
Daniela Hanganu
,
C. Catoi
,
Orsolya Sarpataki
, and
Corina Ionescu

Viscum album L. (Santalaceae) (VA) — a parasitic plant that grows on various trees — has proved a significant anticancer effect in both experimental studies and clinical trials. The present study assesses the influence of oxidative stress in mistletoe induced cytotoxicity in tumor cells, in relation to classic cytostatic therapy. VA ethanolic extract was administered alone and combined with doxorubicin (chloride) in Swiss female mice previously intraperitoneally (i.p.) inoculated with Ehrlich tumor cells (1 × 106/animal) that consequently developed Ehrlich ascites carcinoma (EAC). The administered doses were of 50 mg/kg on the 1st, 3rd and 6th day for the VA extract, respectively of 2.5 mg/kg on the 1st and 6th day for doxorubicin, after tumor cell implantation. Fourteen days later all mice were euthanized, ascites of the EAC were collected in order to analyze the tumor proliferation parameters, as well as blood samples, in order to evaluate the antioxidant status in plasma. Tumor development was associated with increased activity of plasma enzymes; classic doxorubicin therapy not only prevents the accumulation of ascitic fluid, but also significantly reduces the activity of plasma antioxidant enzymes. Furthermore, in association with VA extract, the protective effect is improved. Oxidative changes in Ehrlich tumor cells consisted in decreased catalase activity and amplified xanthine oxidase and peroxidase activities.

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Reaction Kinetics, Mechanisms and Catalysis
Authors:
Viorel Chihaia
,
Karl Sohlberg
,
M. Scurtu
,
C. Hornoiu
,
M. Caldararu
,
C. Munteanu
,
G. Postole
,
N. I. Ionescu
,
T. Yuzhakova
, and
A. Redey

Abstract

The surface dynamics of SnO2/γ-Al2O3 catalysts with different tin dioxide loadings (3 and 20 wt%) prepared by the impregnation method were investigated by using in situ electrical/dielectric measurements. The samples were characterized by BET, inductively coupled plasma atomic emission spectroscopy and X-ray diffraction methods. The propylene oxidation reaction, in the temperature range of 30–400 °C, was used to identify the catalytic activity of SnO2 based catalysts. Results are discussed on the bases of the electrical changes accompanying variation of the active phase content. The conductance/capacitance of supported samples evidenced the reciprocal influence of the support and of the guest oxide.

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