Catalina Daniela Stan

Prof. Dr. Catalina Daniela Stan

Grigore T. Popa University of Medicine and Pharmacy
+1
orcid

Research Focus & Metrics

Academic Career Length

16Years (2011-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 January 2015 in Journal of Nanomaterials
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SPSamoila Petrisor
Samoila Petrisor
CCCorneliu Cojocaru
Corneliu Cojocaru
Igor CRETESCUIgor CRETESCU
Igor CRETESCU
CSCatalina Daniela Stan
Catalina Daniela Stan
NVNica Valentin
Nica Valentin
VHValeria Harabagiu
Valeria Harabagiu
Nanosized spinel ferrites MFe2O4 (M = Ni, Co, and Zn) have been prepared by sol‐gel autocombustion method using citric acid as a fuel agent. The materials are characterized by X‐ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and transmission electron microscopy (TEM). The spinel ferrites have been applied for Congo‐Red (CR) dye adsorption using batch technique. Different kinetic and equilibrium models have been fitted by nonlinear regression to analyze the adsorption data. In accordance with Langmuir isotherm, the maximum adsorption capacity at 293 K is 14.06 mg/g for CoFe2O4 and 17.13 mg/g for NiFe2O4. The values of mean free energy determined from Dubinin‐Radushkevich isotherm are higher than 8 (kJ mol−1), indicating a chemisorption mechanism. Based on the calculated thermodynamic parameters (free energy, enthalpy, and entropy) the adsorption of CR onto ferrites is a spontaneous and endothermic process. Response surface methodology has been applied to construct the multiple regression models for prediction of the adsorption capacity and removal efficiency. The model‐based optimization has been performed using genetic algorithms and desirability function approach. The single‐objective optimization has yielded a maximum value of color removal efficiency of 98.995%, using NiFe2O4 adsorbent. The multiobjective optimization has resulted in the improvement of both removal efficiency and adsorption capacity.

11 April 2022 in Materials
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Nisrine NOUJNisrine NOUJ
Nisrine NOUJ
NHNAIMA HAFID
NAIMA HAFID
NANoureddine El Alem
Noureddine El Alem
IBIngrid Ioana Buciscanu
Ingrid Ioana Buciscanu
SMStelian Sergiu Maier
Stelian Sergiu Maier
CSCatalina Daniela Stan
Catalina Daniela Stan
The nontoxicity, worldwide availability and low production cost of cuttlefish bone products qualify them an excellent biocoagulant to treat food industry wastewater. In this study, cuttlefish bone liquid waste from the deproteinization step was used as a biocoagulant to treat food industry wastewater. This work concerns a waste that has never before been investigated. The objectives of this work were: the recovery of waste resulting from cuttlefish bone deproteinization, the replacementof chemical coagulants with natural ones to preserve the environment, and the enhancement ofthe value of fishery byproducts. A quantitative characterization of the industrial effluents of a Moroccan food processing plant was performed. The physicochemical properties of the raw cuttlefish bone powder and the deproteinization liquid extract were determined using specific analysis techniques: SEM/EDX, FTIR, XRD and 1H-NMR. The protein content of the deproteinization liquid was determined by OPA fluorescent assay. The zeta potential of the liquid extract was also determined. The obtained analytical results showed that the deproteinization liquid waste contained an adequate amount of soluble chitin fractions that could be used in food wastewater treatment. The effects of the coagulant dose and pH on the food industrial effluents were studied to confirm the effectiveness of the deproteinization liquid extract. Under optimal conditions, the coagulant showed satisfactory results. Process optimization was performed using the Box–Behnken design and response surface methodology. Thus, the optimal removal efficiencies predicted using this model for turbidity (99.68%), BOD5 (97.76%), and COD (82.92%) were obtained at a dosage of 8 mL biocoagulant in 0.5 L of food processing wastewater at an alkaline pH of 11.

1 January 2012 in International Journal of Photoenergy
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DLDoina Lutic
Doina Lutic
CCCristina Coromelci-Pastravanu
Cristina Coromelci-Pastravanu
Igor CRETESCUIgor CRETESCU
Igor CRETESCU
IPIoannis Poulios
Ioannis Poulios
CSCatalina Daniela Stan
Catalina Daniela Stan
The photocatalytic activity of zinc oxide, prepared by precipitation followed by calcination, was tested using rhodamine 6G as a rebel organic compound. The experiments were planned in order to allow an optimization procedure, by investigating the effects of different parameters such as the preparative method of the solid, amount of photocatalyst, pH of the reaction medium, and initial concentration of the dye. The results were compared with those obtained on P-25 Titania, and one of the samples had similar performances in terms of dye degradation degree, but needed higher pH values to prevent the photocatalyst degradation.

8 June 2022 in Medicina
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MAMona Akad
Mona Akad
Razvan SocolovRazvan Socolov
Razvan Socolov
CFCristina Ozana Furnica
Cristina Ozana Furnica
RCRoxana Covali
Roxana Covali
CSCatalina Daniela Stan
Catalina Daniela Stan
IPIoana Pavaleanu
Ioana Pavaleanu
Background and objectives: Kisspeptin, also named metastin, showed important roles in initiating the secretion of gonadotropin-releasing hormone (GnRH) and is an essential factor in the development of polycystic ovaries syndrome (PCOS). Several research studies noticed associations between kisspeptin levels and patients with anovulatory cycles due to PCOS with an increased LH/FSH ratio. The aim of our study was to bring scientific evidence regarding the correlation between high kisspeptin and luteinizing hormone values in subfertile women due to PCOS. Materials and Methods: A prospective case-control study was conducted in “Elena Doamna” Hospital of Obstetrics and Gynecology between 4 January 2021 and 1 March 2022. All patients agreed to participate in our study, had ages between 18 and 45 years old, and had a body mass index between 18.5 and 30 kg/m2. The study group consisted of subfertile patients with PCOS and menstrual disturbances, including amenorrhea or oligomenorrhea. The control group consisted of healthy patients with ovulatory cycles and no other reproductive or endocrinology pathologies. During the follicular phase of their menstrual cycle, patients had blood samples taken with the dosage of kisspeptin, LH, FSH, estradiol, insulin, glycemic levels, testosterone, and prolactin. Pelvic ultrasounds and clinical examinations were performed as well. Results: Significant differences were observed in kisspeptin, LH, FSH, and estradiol levels between patients with PCOS and the control group. After the univariate analysis, PCOS was significantly associated with increased kisspeptin, increased LH, and decreased FSH. There was no significant association between PCOS, estradiol, prolactin, and insulin. Conclusions: kisspeptin serum values are higher in subfertile PCOS patients, supporting the hypothesis that an over-stimulation of the KISS1 system might cause the hyper-stimulation of the HPG-axis.

15 December 2020 in Materials
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ASAli Dawood Salman
Ali Dawood Salman
TJTatjana Juzsakova
Tatjana Juzsakova
MJMoayed G Jalhoom
Moayed G Jalhoom
Phuoc Cuong LePhuoc Cuong Le
Phuoc Cuong Le
SMSaja Mohsen
Saja Mohsen
CSCatalina Daniela Stan
Catalina Daniela Stan
The aim of this study was to prepare novel supramolecular hybrid nanoparticles (HNPs) that can selectively separate and recover scandium metal ions, Sc(III), from an aqueous phase based on molecular recognition technology (MRT). Moreover, this approach is fully compatible with green chemistry principles. In this work, natural amorphous silica (SiO2) nanoparticles were prepared by a precipitation method from Iraqi rice husk (RH) followed by surface modification with 3-amino-propyl triethoxysilane (APTES) as coupling agent and Kryptofix 2.2.2 (K2.2.2) as polycyclic ligand. To evaluate the potential of the hybrid nanoparticles, the prepared HNPs were used for the solid–liquid extraction of scandium, Sc(III), ions from model solutions due to the fact that K2.2.2 are polycyclic molecules. These polycyclic molecules are able to encapsulate cations according to the corresponding cavity size with the ionic radius of metal by providing a higher protection due their cage-like structures. Moreover, the authors set the objectives to design a high-technology process using these HNPs and to develop a Sc recovery method from the aqueous model solution prior to employing it in industrial applications, e.g., for Sc recovery from red mud leachate. The concentrations of Sc model solutions were investigated using the UV-Vis spectrophotometer technique. Different characterization techniques were used including scanning electron microscope (SEM), atomic force microscopy (AFM), Brunauer–Emmett–Teller (BET), X-ray diffraction (XRD), X-ray fluorescence (XRF), and Fourier transform infrared (FTIR). The extraction efficiency of Sc varied from 81.3% to 96.7%. Moreover, the complexed Sc ions were efficiently recovered by HCl with 0.1 mol/L concentration. The stripping ratios of Sc obtained ranged from 93.1% to 97.8%.

9 October 2012 in International Journal of Photoenergy
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CSCatalina Daniela Stan
Catalina Daniela Stan
Igor CRETESCUIgor CRETESCU
Igor CRETESCU
CPCristina Pastravanu
Cristina Pastravanu
IPIoannis Poulios
Ioannis Poulios
MDMaria Drăgan
Maria Drăgan
The effect of different heterogeneous and homogeneous photocatalytic systems on the oxidative degradation of mepiquat chloride in aqueous solutions was investigated. In the case of heterogeneous reactions, the influence of five factors was studied: the type of catalyst, photocatalyst concentration, pH, pesticide concentration, and the presence of H2O2and/or Fe3+. For homogeneous catalysis, other factors were studied: the oxidising agent and the light source. Nearly complete degradation of mepiquat chloride was obtained after about 180 minutes in the presence of an acid medium (pH3) using a UV-A lamp and TiO2P-25 catalyst (0.5 g/L), for an initial pesticide concentration of 10 ppm. Degradation rates corresponding to homogeneous photocatalysis were lower compared to those corresponding to the use of TiO2as the photocatalyst.