We report room-temperature Raman studies of strained (100) and (311)B GaAs1-xBix epitaxial layers for x ≤ 0.039. The Raman spectra exhibit a two-mode behavior, as well as disorder-activated GaAs-like phonons. The experimental results show that the GaAs-like LO(Γ) mode experiences a strong composition-dependent redshift as a result of alloying. The peak frequency decreases linearly from the value for pure GaAs (∼293 cm-1) with the alloyed Bi fraction x and the introduced in-plane lattice strain ε, by Δ ω LO = Δ ω alloy-Δ ω strain. X-ray diffraction measurements are used to determine x and ε allowing Δ ω alloy to be decoupled and is estimated to be-12(±4) cm-1/x for (100) GaAs1-xBix. Δ ω LO is measured to be roughly double for samples grown on (311)B-oriented substrates to that of (100) GaAs. This large difference in redshift is accounted for by examining the Bi induced strain, effects from alloying, and defects formed during high-index (311)B crystal growth. Raman scattering studies of strain effects in (100) and (311) We report room-temperature Raman studies of strained (100) and (311)B GaAs 1Àx Bi x epitaxial layers for x 0.039. The Raman spectra exhibit a two-mode behavior, as well as disorder-activated GaAs-like phonons. The experimental results show that the GaAs-like LO(C) mode experiences a strong composition-dependent redshift as a result of alloying. The peak frequency decreases linearly from the value for pure GaAs ($293 cm À1) with the alloyed Bi fraction x and the introduced in-plane lattice strain e k , by Dx LO ¼ Dx alloy À Dx strain . X-ray diffraction measurements are used to determine x and e k allowing Dx alloy to be decoupled and is estimated to be À12(64) cm À1

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Heterocyclic compounds, including pyrimidine derivatives, exhibit a broad variety of biological and pharmacological activities. In this paper, a previously synthesized novel pyrimidine molecule is proposed, and its pharmaceutical properties are investigated. Computational techniques such as the density functional theory, ADMET evaluation, and molecular docking were applied to elucidate the chemical nature, drug likeness and antibacterial function of molecule. The viewpoint of quantum chemical computations revealed that the molecule was relatively stable and has a high electrophilic nature. The contour maps of HOMO-LUMO and molecular electrostatic potential were analyzed to illustrate the charge density distributions that could be associated with the biological activity. Natural bond orbital (NBO) analysis revealed details about the interaction between donor and acceptor within the bond. Drug likeness and ADMET analysis showed that the molecule possesses the agents of safety and the effective combination therapy as pharmaceutical drug. The antimicrobial activity was investigated using molecular docking. The investigated molecule demonstrated a high affinity for binding within the active sites of antibacterial and antimalarial proteins. The high affinity of the antibacterial protein was proved by its low binding energy (−7.97 kcal/mol) and a low inhibition constant value (1.43 µM). The formation of four conventional hydrogen bonds in ligand–protein interactions confirmed the high stability of the resulting complexes. When compared to known standard drugs, the studied molecule displayed a remarkable antimalarial activity, as indicated by higher binding affinity (B.E. −5.86 kcal/mol & Ki = 50.23 M). The pre-selected molecule could be presented as a promising drug candidate for the development of novel antimicrobial agents.

Basic electronic properties relevant to the carrier mobility were studied in tin oxide thin films doped with fluorine, prepared by atmospheric pressure chemical vapor deposition. Electrical resistivity, Hall and Seebeck effects, plasma and collision frequencies were measured (the last two by using multiangle spectral ellipsometry) and analyzed for films with carrier concentrations from 1.8×1020 to 5.6×1020 cm−3. Scanning over the sample area of resistivity (four-point probe method) and Seebeck coefficient (thermoprobe) monitored uniformity of electronic properties in plane. Ellipsometry was used to check uniformity over the film thickness. Films with a thickness above 400 nm demonstrated high spatial uniformity and were used for further studies.Effective mass was determined from combined Hall and plasma frequency measurements and was found to be independent of carrier concentration, which indicates a parabolic band spectrum. Its value was very close to the literature data. In films with carrier concentration ≥3×1020 cm−3 the Hall mobility was very close to the optical mobility calculated based on collision frequency and effective mass values. This indicates a very small contribution of grain boundaries to the total resistivity of films. Thus the measured mobility is close to the electron mobility in the grain bulk.The scattering parameter value derived from thermopower measurements along with the temperature independent mobility indicated that electron scattering by impurity ions screened by free carriers is the dominating scattering mechanism. Theoretical estimates of mobility are very close to the highest measured mobility values (≥ 30 cm2/Vs) if the spatial dispersion of the dielectric constant is taken into account. Comparison of differently processed films showed that compensation of donor dopant with uncontrolled acceptor centers significantly impacted mobility.

We report a facile and friendly to the environment method for the preparation of superparamagnetic γ-Fe 2 O 3 /Gd 2 O 3 -chitosan nanocomposite for magnetic hyperthermia application. The nanocomposite was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), vibrating sample magnetometer, Scanning electron microscopy and Energydispersive X-ray spectroscopy (EDAX). In addition, the heating efficiency and biocompatibility with human cells are reported. XRD patterns indicated that the most dominant crystalline phase is γ-Fe 2 O 3 with the presence of chitosan in the coated sample. FT-IR and EDAX confirmed the presence of chitosan on the surface of the nanostructure. Magnetic measurements showed the superparamagnetic behavior with decrease in saturation after coating due to diamagnetic nature of chitosan. This behavior is corroborated by the successfully fitting into Langevin function for paramagnetic materials. The specific absorption rate under an alternating magnetic field is investigated as a function of the concentration and amplitude of the applied magnetic field. A mean heating efficiency of 35 W/g is obtained for concentration of 15 mg/ml at 332 kHz and 170 Oe. It was found that the heating efficiency of the nanocomposite can be tuned by changing parameters such as concentration and amplitude of applied AC magnetic field. Cell viability assay of coated nanocomposite showed low cytotoxic effect on A549 cells line (human alveolar epithelial). In overall, the prepared nanocomposite can be used as potential candidate for magnetic hyperthermia application due to their superparamagnetic nature, heating ability and biocompatibility with human cells.