243 research outputs found
Considerations on hospital financing in the context of health care decentralization
2010 represented the moment when the reform was applied in the health field by decentralizing the management ofthe health units with beds (hospitals). This analysis points out the way hospital financing was carried out after that and the main problems the health care system of Romania has to deal with. In the end there are presented a few personal considerations on the main challenges for the futur
Studiul cinetic al îndepărtării ionilor de Pb(II) şi Hg(II) din medii apoase pe biomasă de rapiţă
In this study, the removal of Pb(II) and Hg(II) ions from aqueous solution using rapeseeds biomass was examined in batch systemsas a funtion of contact time. The results obtained for the removal of each studied metal ion were analyzed using three kinetics models: prseudo-first order, pseudo-second order and intra-particle diffusion, in order to elucidate the mechanism of the removal process. For both studied metal ions, the experimental data are well described by the pseudo-second order kinetics model. Theseresults can be used for to highlight the potential applicability of rapeseeds biomass as low-cost biosorbent in the clean-up of aqueous effleunts, containing toxic heavy metals
Pedogeochemistry of hortic anthrosol from Copou greenhouse – Iaşi (I)
The soil from Copou greenhouse – Iasi is a mixic-proxicalcaric-hipohortic entianthrosol (profile IS.1), associated with
proxicalcaric–hortic-anthrosol (profile IS.2). Characteristic for this anthrosol is the formation at depth of 12–48 cm of
Ahok horizons, proto-frangipanes or frangipanes, which determined the differential evolution of pedogeochemical
processes in soil profiles (geochemical segregation phenomena). The studied soils fall within the class of medium and
fine textured, the dominant particles size fractions (with very close weight) being sand and clay. The migration and
accumulation tendency of fine particles size fractions at Ahok(x)2 horizon level represent one of the conditions for
frangipane horizons formation and developing of geochemical segregation phenomena. For upper horizons of profiles
are characteristics neutral conditions – weak alkaline and moderately oxidizing, and for bottom horizons are
characteristic neutral conditions – weak acid and moderately reducing. Following the total soluble salts content
(variation limits: 152.92–688.02, average: 382.87 mg / 100 g soil), the upper horizons are highly salinized (Apk1) and
moderately salinized (Apk2, Ahok(x)1 and Ahok(x)2), and the bottom horizons are weak salinized. The total
phosphorus content varied between 94.57–768.05 μg P2O5/g soil, with an average of span by 53.95 % from total
phosphorus. The inorganic phosphorus represents 46.03 % from total phosphorus, and the organic phosphorus is 53.95
% from total phosphorus. The phosphorus extractable in acetate – lactate, non-occluded phosphorus, varied between
90.09–740.09 μg P2O5/g soil, with an average of span by 366.50 μg P2O5/g soil (which represents 94.73 % from total
phosphorus)
Rayleigh waves in isotropic elastic materials with micro-voids
In this paper, we show that a general method introduced by Fu and Mielke
allows to give a complete answer on the existence and uniqueness of a subsonic
solution describing the propagation of surface waves in an isotropic half space
modelled with the linear theory of isotropic elastic materials with
micro-voids. Our result is valid for the entire class of materials admitting
real wave propagation which include auxetic materials (negative Poisson's
ration) and composite materials with negative-stiffness inclusions (negative
Young's modulus). Moreover, the used method allows to formulate a simple and
complete numerical strategy for the computation of the solution.Comment: arXiv admin note: text overlap with arXiv:2104.1314
Comparison of the evolution of the COVID-19 disease between Romania and Italy
After the outbreak of COVID-19 in Italy, thousands of Romanian citizens who worked in Northern Italy, Spain or Germany returned to Romania. Based on the time-dependent susceptible–infected–recovered—SIR model, this paper compares the evolution of the COVID-19 disease between Romania and Italy, assuming that the parameter value of R0 in the time-dependent SIR model decreases to R1 < R0 after publicly announced restrictions by the government, and increases to a value of R2 < R1 when the restrictions are lifted. Among other things, we answer the questions about the date and extent of the second peak in Italy and Romania with respect to different values of R2 and the duration of the restrictions
Recent advances in biosorption of heavy metals: support tools for biosorption equilibrium, kinetics and mechanism
Heavy metals are increasingly present in industrial wastes and effluents,
which can generate serious concerns for environmental quality and
human health. Consequently, there is a continuous expansion of
researches for new approaches and developments to guarantee
environmental cleaning-up. Although there are some physico-chemical
established methods for the removal of heavy metals from various
environmental compartments, biosorption gains further confidence as a
reliable alternative compared to classical technologies, which are
expensive and sometimes unreliable. This paper aims to analyze the
biosorption as a biotechnological strategy for the decontamination of
aqueous effluents containing heavy metal ions, in terms of its potential
for metal immobilization and uptake. The paper also focuses on the most
important parameters affecting the removal of heavy metals by various
categories of biosorbents both living and non-living forms of biomass
and provides new alternatives for modeling and optimization of
process equilibrium and kinetics. A special attention was paid to
biosorption mechanism, as a factual challenge for process optimization
and scale-up. The potential benefits and problems associated to metal
removal by biosorption are highlighted.Roumanian National Authority for Scientific Research, CNCS – UEFISCDI, project number PN-II-ID-PCE-2011-3-0559”, Contract 265/2011
Fragipanization phenomenon – effects on soils pedogeochemistry from protected areas (greenhouses and solariums)
In this paper are presented several new aspects related to the effects of fragipanization phenomenon on
pedogeochemical processes in particular case of soils from protected areas (greenhouses and solariums). A special
attention was paid to dynamic evolution of macro- and micro-elements in conditions of soils from protected areas,
affected by fragipanization phenomenon, and to the correlation between these and pedogeochemical segregation and
salinization processes. In addition, were highlighted a number of issues relating to the conditions of emergence and
dynamics of the frangipane in soils from protected areas. The fragipane represents both a degradation phenomenon and
an initiator for soil degradation phenomena. The formation of fragipane horizons is directly correlated with the
apparition and development of pedogeochemical segregation, compaction and salinization processes that have strong
negative influence on pedological and agrochemical characteristics of soils. The impacts fragipane is highlights, in
general, by: (i) the discontinuity of water circulation in the soil profile, (ii) contrasting physico-chemical conditions
between the upper and lower horizons, (iii) particular and atypical evolutions of the organic matter dynamics, speciation
processes and inter-phase distribution of macro- and micro-elements etc., (iv) simultaneously with the formation
horizons fragipane (emphasis segregation pedogeochimice) are rapidly degraded the physical-chemical and
agrochemical characteristics of soils, with negative effects on their productivity and quality of obtained agricultural
products
Consideraţii asupra calităţii lucrărilor de afânare adâncă a solului utilizând analiza statistică
The field surveys were conducted within the North-East development region on oderately inclined terrain. The primary data were obtained from the vertical sections of the ground made perpendicular to the forward direction of the soil tiller. The width of the cross-sections was 2 m and the depth of 1.2 m. The primary data obtained from the measurements of the vertical sections made were subsequently processed mathematically. In order to further verify the significance of the differences occurring within a plot, the use of mathematical methods for analyzing the area, volume and shape of the tiled surface has been attempted, which will allow the researcher a larger number of checks under optimal conditionsusing the mathematical statistical apparatus. Key words:deep soil loosening works, soil, statistical analysi
The evaluation of factors affecting sorption of pentachlorophenol in soil
The release of persistent organic pollutants (POPs) derived from different industrial processes represents an important
source of environmental contamination. Pentachlorophenol (PCP) is a highly chlorinated organic compound that has
been extensively used as a broad spectrum biocide, particularly in the wood preservation industry. Due to its stable
aromatic ring structure and high chlorine content, PCP is persistent in the environment, and it has become one of the
most widespread contaminants in soil, sediments and water. In soil, the fate of POPs is governed by their interactions
with reactive soil colloids. The soil properties as well as the chemical properties of the pollutants, control its
bioavailability and transport, thus, affecting further remediation processes. The main objective of the present work was
to study the sorption of pentachlorophenol in soil, collected from Iasi area (Romania). The experiments were performed
in batch mode. Interest was directed towards the effects of contact time (0-72 h), initial pollutant concentration (5 - 20
mg L-1), pH and temperature (10 - 50oC). The sorbed amounts of PCP increased with increase in contact time and
initial concentration and reached the equilibrium after 24 h. Pentachlorophenol sorption increase with temperature in the
range of 10-25oC, suggesting an endothermic process, and decrease when the temperature increased from 25 to 50°C.
The results indicated that lower temperature (i.e. 10 to 25°C) was favorable for the sorption process. The high
temperature (50°C) might affect the physicochemical properties of soil therefore; the sorption PCP on soil was
significantly reduced
Optimizarea parametrilor de biosorbţie pentru reţinerea ionilor de Cu(II) pe biomasă de alge marine roşii şi verzi
Marine algae are an important biomass resource because of the many properties they have in solving various environmental problems such as the ability to decontaminate wastewater, soil decontamination, soil fertilization, etc. Heavy metal pollution is a problem for the environment. The development of industrial activities has led to increased emissions of heavy metals into the environment, with negative consequences for soils, plants, rivers and waters. Therefore, it is necessary to find appropriate methods that should be environmentally friendly in removing metal ions in a more efficient and inexpensive way. In this paper we optimized the biosorption parameters (pH, initial concentration and contact time) for the retention of Cu (II) ions on algae biomass, using two types of marine algae: a red one Callithamnion corymbosum sp. and a green one -Ulva lactuca sp. from aqueous solution
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