Synthesis,characterization, antifungal and antibacterial activities evaluation of copper (II), zinc (II) and cadmium (II) chloride and bromide complexes with new (E)-1-(3,4-dimethoxybenzylidene)-4-methylthiosemicarbazone ligand

The reactions of Cu (II), Zn (II) and Cd (II) chloride or bromide with (E)-1-(3,4-dimethoxybenzylidene)-4-methylthiosemicarbazone (MTSVT) lead to the formation of new complexes. They were characterized by spectroscopic studies: IR, ¹H and ¹³C NMR. The crystal structures of the compounds [MTSVT] ( L ), [ZnBr₂(MTSVT)₂] ( 2 ), [CdCl₂(MTSVT)₂] ( 3 ) and [CdBr₂(MTSVT)₂^.H₂O] ( 4 ) were determined by X-ray diffraction. For complexes 2 – 4 , the ion is coordinated through the sulfur atom. All compounds were tested for their antifungal activity against human pathogenic fungi Candida albicans and Aspergillus fumigatus, and for their antibacterial activity against Gram (+) Bacillus subtilis and Enterococcus faecalis as well as against Gram (−) bacteria such as Paracoccus yeei and Acinetobacter baumanii. The results indicated that the metal complexes exhibited a marked enhancement in antibacterial activity compared with the parent Schiff base.     

Wetting phenomena during processing of high-viscosity shear-thinning fluid

Slot-die coating windows have been previously obtained by several researchers for low-viscosity solutions. However, practical applications necessitate the use of relatively high-viscosity (?1 Pa s) non-Newtonian fluids for coating films. Also, earlier theoretical studies predicting coating windows are mainly limited to 2D single-phase studies, and based the prediction of the coating window on the upstream contact angle made by the coating fluid with the substrate. The numerical predictions varied significantly from the experimental findings in most cases due to oversimplification of the model. In the current study, experimental and theoretical methods are used for obtaining the coating window for blackstrap molasses, which is classified as a relatively high-viscosity, shear thinning solution. The coating process is monitored by a microscope connected to a camera placed under the slot-die. Air entrainment is found to occur in a three-step or four-step cycle. In addition, a comprehensive theoretical study is performed by simulating the coating process using a 3D, multiphase, volume of fluid (VOF) method. The simulation is found to predict the coating window within 10% accuracy of experimental results. Also, the model does an excellent job of predicting the formation of air bubbles at high coating speeds.     

Laser processing of ormosils for tissue engineering applications

Hybrid methacrylates based on silane derivates (ormosils) have been considered for applications in electronics, microtechnology, corrosion resistant coatings, dentistry, and biomedical implants. The presence of both inorganic chains, responsible for chemical and thermal stability, hardness, and transparency, and organic groups, which bring new advantages such as the possibility of functionalization and easy, low temperature processing, can result in the appearance of unique properties.     

Y2O3 Nanoparticles and X-ray Radiation-Induced Effects in Melanoma Cells

The innovative strategy of using nanoparticles in radiotherapy has become an exciting topic due to the possibility of simultaneously improving local efficiency of radiation in tumors and real-time monitoring of the delivered doses. Yttrium oxide (Y₂O₃) nanoparticles (NPs) are used in material science to prepare phosphors for various applications including X-ray induced photodynamic therapy and in situ nano-dosimetry, but few available reports only addressed the effect induced in cells by combined exposure to different doses of superficial X-ray radiation and nanoparticles. Herein, we analyzed changes induced in melanoma cells by exposure to different doses of X-ray radiation and various concentrations of Y₂O₃ NPs. By evaluation of cell mitochondrial activity and production of intracellular reactive oxygen species (ROS), we estimated that 2, 4, and 6 Gy X-ray radiation doses are visibly altering the cells by inducing ROS production with increasing the dose while at 6 Gy the mitochondrial activity is also affected. Separately, high-concentrated solutions of 25, 50, and 100 µg/mL Y₂O₃ NPs were also found to affect the cells by inducing ROS production with the increase of concentration. Additionally, the colony-forming units assay evidenced a rather synergic effect of NPs and radiation. By adding the NPs to cells before irradiation, a decrease of the number of proliferating cell colonies was observed with increase of X-ray dose. DNA damage was evidenced by quantifying the γ-H2AX foci for cells treated with Y₂O₃ NPs and exposed to superficial X-ray radiation. Proteomic profile confirmed that a combined effect of 50 µg/mL Y₂O₃ NPs and 6 Gy X-ray dose induced mitochondria alterations and DNA changes in melanoma cells.     

Pd-Catalyzed enantioselective synthesis of 2-methyl-3-methyleneindoline

A Pd-catalyzed enantioselective synthesis of 2-methyl-3-methyleneindoline in up to 89% yield and 84% ee from racemic vinyl benzoxazinanones has been developed with the help of(R,R)-BenzP*ligand.Mechanism studies support the formation of palladacyclobutane as the key intermediate via C2 attack to π-allyl Pd complex.The β-hydride elimination provides a new reaction pathway for the palladacyclobutane.     

Ion beam analysis of elemental signatures in uranium dioxide samples: importance for nuclear forensics

In this paper the suitability of two non-destructive analytical techniques for identification of elemental signatures in samples containing uranium of different enrichments was studied. The measurements were based on particle induced X-ray emission (PIXE) and particle induced gamma-ray emission (PIGE) methods. The samples were irradiated by 3 and 5 MeV protons at the 3 MV Tandetron™ of Horia Hulubei National Institute for Physics and Nuclear Engineering. The characteristic X and gamma rays were measured using high purity germanium (HPGe) detectors. The GUPIX software was applied for processing the PIXE spectra, while a relative standardization was applied for PIGE analysis by using certified comparator standards and proton stopping powers calculated by SRIM.

     

A Hybrid Symbiosis Organisms Search algorithm and its application to real world problems

In this paper, a new hybrid algorithm, Hybrid Symbiosis Organisms Search (HSOS) has been proposed by combining Symbiosis Organisms Search (SOS) algorithm with Simple Quadratic Interpolation (SQI). The proposed algorithm provides more efficient behavior when dealing with real-world and large scale problems. To verify the performance of this suggested algorithm, 13 (Thirteen) well known benchmark functions, CEC2005 and CEC2010 special session on real-parameter optimization are being considered. The results obtained by the proposed method are compared with other state-of-the-art algorithms and it was observed that the suggested approach provides an effective and efficient solution in regards to the quality of the final result as well as the convergence rate. Moreover, the effect of the common controlling parameters of the algorithm, viz. population size, number of fitness evaluations (number of generations) of the algorithm are also being investigated by considering different population sizes and the number of fitness evaluations (number of generations). Finally, the method endorsed in this paper has been applied to two real life problems and it was inferred that the output of the proposed algorithm is satisfactory.     

Microstructural Study of Nylon-6/Gelatin Composite Nanofibers

Electrospinning is a simple and effective technology for fabricating nanofibers and polymer blending provides strength and minimal defects of electrospun ones. Therefore, in the present study, fabrication, and characterization of nylon-6/gelatin electrospun nanofibers using low-toxic solvents was investigated as means to improve the morphological deficiencies of gelatin nanofibers and facilitate its electrospinnability. The morphology of electrospun nylon-6/gelatin nanofibers were characterized using scanning electron microscope (SEM). SEM results showed that electrospun blend nanofibers had smooth surface with average diameter of from 40 to 100 nm; while, the miscibility of the blend and thermal behavior of nanofibers were determined using Fourier transform-infrared spectroscopy (FTIR) and differential scanning calorimeter (DSC). Water contact-angle measurement (WCA) was employed to investigating the wettability of nanofibers.     

New high-pressures vapor-liquid equilibrium data for the carbon dioxide + 2-methyl-1-propanol (isobutanol) binary system

New vapor-liquid equilibria (VLE) data at 333.15, 343.15, and 353.15 K and pressures up to 130.0 bar are reported for the carbon dioxide + 2-methyl-1-propanol (isobutanol) system. The experimental method used in this work was a static analytical method with liquid and vapor phases sampling using a rapid online sampler injector (ROLSITM) coupled to a gas chromatograph (GC) for analysis. Measured VLE data and literature data for carbon dioxide + 2-methyl-1-propanol system were modeled with the Soave-Redlich-Kwong (SRK) cubic equation of state with classical van der Waals (two-parameter conventional mixing rule, 2PCMR) mixing rules. A single set of interaction parameters that lead to a correct phase behavior was used in this work to model the new VLE data and critical points of the mixtures in a wide range of temperature and pressure. The SRK prediction results were compared to the new data measured in this study and to available literature data.

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Microencapsulation of Calcium Using Water-in-Oil-in-Water Double Emulsion Method

Calcium in the form of tricalcium phosphate was encapsulated in the inner water phase of water-in-oil-in-water emulsion. Efficiency and payload of microcapsules were optimized using a D-optimal mixture design with four components (gelatin, agar, primary water-in-oil emulsion, and water in outer phase). Release profiles of calcium from microcapsules were determined at 4°C over 12 days. It was found that microencapsulation efficiency increased by increasing of water-in-oil emulsion to 45% and then decreased at higher contents of this portion. However, payload increased continuously with increase of water-in-oil fraction. Less calcium was released when both biopolymers and water-in-oil emulsion contents were increased.