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1.
Sci Rep ; 14(1): 1815, 2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38245584

RESUMO

The effect of temperature on electrochemical properties of Ni82.3Cr7Fe3Si4.5B3.2 glassy alloy in different acid proticity has been investigated utilizing AC and DC methods. Firstly, the handling of experimental data on the temperature dependence of charge transfer resistance, as well as corrosion current density permits us to determine the values of classical Arrhenius parameters as well as the thermodynamic ones considered approximately independent of temperature. This leads us to deduce a global interpretation on the phenomenon of corrosion and polarization. Secondly, the deviation to the linearity of the Arrhenius behavior and the real dependence on temperature of the thermodynamic parameters, permit us to clearly quantify the effect of the acid proticity and define, for the first time, the concept of current Arrhenius parameters and the current thermodynamic ones, as well as the modeling of the enthalpy-enthalpy compensation. Moreover, the effect of temperature can be investigated using the Vogel-Fulcher-Tammann model to reveal that the corresponding Vogel temperature has an interesting physical meaning.

2.
Heliyon ; 10(17): e36836, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39263161

RESUMO

In this paper, an empirical model with the critical number of incidences and deaths for female cancers as adjustable parameters has been developed using life expectancy data from GLOBOCAN world estimates on cancer types. The model was developed based on the cumulative risk and exponential correlation techniques such that the significance of the adjustable parameters ascertains the strength of this research in two ways. First, it indicates indicates the rapid increase in female cancer morbidity with increase in the number of male cancer cases, regardless of incidence or mortality. Second, it suggests that female cancer cases may approach a virtual limiting value as male cancer cases reach extremely high levels. This projection aligns with the global population trends, indicating a proportional increase in cancer cases each year. Additionally, the cumulative risk of cancer incidences of each sex has been modelled separately against the global cumulative risk of cancer incidences of both sexes which revealed regions that have passed their inflection point and those that are yet to reach the inflection point. There was a curvature change, which indicates an inflection point coinciding with the South-Eastern Region and indicating that for the regions beyond the inflection point, the increase of the cumulative risk of cancer incidences of females against that of males is more accentuated compared with the regions before the inflection point. However, when the cumulative risk of cancer mortality of each sex is modelled separately against the global cumulative risk of cancer mortality of both sexes shows a non-linear dependence and the increase is more accentuated for males than for females. This finding indicates that cumulative risk is influenced by factors beyond the male-female population ratio. This study advances cancer studies as it provides a nuanced understanding of gender-specific cancer trends, crucial for developing targeted cancer prevention and treatment strategies. By elucidating the dynamics of cancer incidences and mortalities across different regions and sexes, the findings can inform public health policies and resource allocation to combat cancer more effectively on a global scale.

3.
Artigo em Inglês | MEDLINE | ID: mdl-35329394

RESUMO

This report develops a conceivable mathematical model for the transmission and spread of COVID-19 in Romania. Understanding the early spread dynamics of the infection and evaluating the effectiveness of control measures in the first wave of infection is crucial for assessing and evaluating the potential for sustained transmission occurring in the second wave. The main aim of the study was to emphasize the impact of control measures and the rate of case detection in slowing the spread of the disease. Non pharmaceutical control interventions include government actions, public reactions, and other measures. The methodology consists of an empirical model, taking into consideration the generic framework of the Stockholm Environment Institute (SEI) Epidemic-Macroeconomic Model, and incorporates the effect of interventions through a multivalued parameter, a stepwise constant varying during different phases of the interventions designed to capture their impact on the model. The model is mathematically consistent and presents various simulation results using best-estimated parameter values. The model can be easily updated later in response to real-world alterations, for example, the easing of restrictions. We hope that our simulation results may guide local authorities to make timely, correct decisions for public health and risk assessment.


Assuntos
COVID-19 , Epidemias , COVID-19/epidemiologia , Simulação por Computador , Humanos , Saúde Pública , Medição de Risco
4.
Sci Rep ; 12(1): 6432, 2022 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-35440686

RESUMO

Temperature plays an important role in promoting the corrosion of metals. The Arrhenius plot can interpret the corrosion rate-temperature dependence, where the Arrhenius behavior gives a geometrical meaning and makes explicit a positive or negative linear dependence of charge transitivity and temperature. In addition, according to the Arrhenius interpretation, it represents the energy that the molecule in the initial state of the process must acquire before it can take part in the reaction, whether it is a physical, or a chemical process. Taking into account the deviation from the linearity, we have extended the Arrhenius-type expression by one term in 1/T2 and we have given some physical meaning to the new related coefficients for which it is found that they depend closely on the number of acid hydrogen atoms in the polyacid for the corrosion and passivation of the Nickel based metallic glass alloy of the composition Ni82.3Cr7Fe3Si4.5B3.2. Moreover, we can consider that the deviation to the Arrhenius linear behavior as a super-Arrhenius behavior In addition, a mathematical analysis of the trend of experimental scatter points of the charge transfer resistance with temperature permits us to reveal an interesting homographic behavior which leads us to suggest an original empirical model with only two optimal adjustable parameters, as well as a new pseudo-power dependence of the number of hydrogen atoms in the polyacid.

5.
Nanomaterials (Basel) ; 11(4)2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33918847

RESUMO

Penicillin G is an old and widely used antibiotic. Its persistence in the environment started to appear in many environmental samples and food chains. The removal of these emerging pollutants has been a challenging task for scientists in the last decades. The photocatalytic properties of Cd2+ doped Manganese- Zinc NSFs with chemical formula (Mn0.5Zn0.5)[CdxFe2-x]O4 (0.0 ≤ x ≤ 0.05) NSFs are herein evaluated. The Manganese- Zinc N.S.F.s nanomaterials were deeply characterized, utilizing UV-Vis (reflectance) spectroscopy, X-ray diffraction, N2 adsorption isotherm measurements, and S.E.M., SEM-EDX mapping, and T.E.M. The Kinetic model for the photodegradation of penicillin G (as a model molecule) is investigated using visible light as a source of energy. The kinetic study shows that our results fit well with the modified pseudo-first-order model. The Pen G degradation are 88.73%, 66.65%, 44.70%, 37.62% and 24.68% for x = 0.5, 0.4, 0.3, 0.2 and 0.1, respectively, against 14.68% for the free Cd spinel sample. The pseudo-rate constant is bandgap dependent. From the intra-diffusion rate constant (Kd), we developed an intra-diffusion time (τ) model, which decreases exponentially as a function of (x) and mainly shows the existence of three different domains versus cadmium coordination in spinel ferrite samples. Hence, Cadmium's presence generates spontaneous polarization with a strong opportunity to monitor the charge separation and then open the route to a new generation of "assisted" photocatalysts under visible light.

6.
Sci Rep ; 10(1): 67, 2020 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-31919389

RESUMO

The effect of gamma-irradiation and ionizing radiation (high-energy electrons beam) on the physicochemical properties of metoprolol tartrate at the solid phase and aqueous solution, has been investigated in the present study to model some properties affected by absorbed doses and to reveal some interesting mutual causal correlation. The proposed some interesting models can be adapted to other experimental conditions, and the newly obtained values of the adjustable parameters could be an excellent criterion of the state quality of the metoprolol tartrate or for other additional interpretations. The peculiar behaviour of variation of physicochemical properties against dose leads us to confirm the suggested optimized doses mentioned in previous work, for sterilization and safe medical uses.

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