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91.
Ehab M. Abdalla Safaa S. Hassan Hussein H. Elganzory Samar A. Aly Heba Alshater 《Molecules (Basel, Switzerland)》2021,26(19)
New Pb(II), Mn(II), Hg(II), and Zn(II) complexes, derived from 4-(4-chlorophenyl)-1-(2-(phenylamino)acetyl)thiosemicarbazone, were synthesized. The compounds with general formulas, [Pb(H2L)2(OAc)2]ETOH.H2O, [Mn(H2L)(HL)]Cl, [Hg2(H2L)(OH)SO4], and [Zn(H2L)(HL)]Cl, were characterized by physicochemical and theoretical studies. X-ray diffraction studies showed a decrease in the crystalline size of compounds that were exposed to gamma irradiation (γ-irradiation). Thermal studies of the synthesized complexes showed thermal stability of the Mn(II) and Pb(II) complexes after γ-irradiation compared to those before γ–irradiation, while no changes in the Zn(II) and Hg(II) complexes were observed. The optimized geometric structures of the ligand and metal complexes are discussed regarding density functional theory calculations (DFT). The antimicrobial activities of the ligand and metal complexes against several bacterial and fungal stains were screened before and after irradiation. The Hg(II) complex has shown excellent antibacterial activity before and after γ-irradiation. In vitro cytotoxicity screening of the ligand and the Mn(II) and Zn(II) complexes before and after γ-irradiation disclosed that both the ligand and Mn(II) complex exhibited higher activity against human liver (Hep-G2) than Zn(II). Molecular docking was performed on the active site of MK-2 and showed good results. 相似文献
92.
Christopher M. Spillmann Jawad Naciri Mu-San Chen Amritha Srinivasan Banahalli R. Ratna 《Liquid crystals》2006,33(4):373-380
In this report we demonstrate the ability to tune the physical properties of a liquid crystal elastomer (LCE) by varying the amount and type of crosslinking within the elastomer network. LCE films composed of a single mesogenic compound were capable of uniaxial contraction when thermally actuated through the nematic to isotropic phase of the material. We probed the physical properties of the LCE films while varying the amount and concentration of two crosslinking agents and measured actuation strains of 10-35%, elastic moduli of 3-14 MPa, and transition temperatures ranging between 75 and 60°C. The viscous losses of the elastomers and the estimated work capable of being produced by the films were also evaluated. The ability to tune the physical properties of the LCE films allows for a wide range of applications including robotics, microelectromechanical systems (MEMS), shape-changing membranes, and/or microfluidics. 相似文献
93.
Raid A. Ismail Ibrahim Ramadhan Aseel Mustafa 《中国物理快报》2005,22(11):2977-2979
Cu2O thin films with (111) preferred orientation have been grown on glass and Cu substrates by rapid thermal oxidation of Cu at 500℃ for 45s. The optical band gap energy was determined by spectral data of transmittance and absorbance to be 2.04eV. The electrical conductivity of grown films was measured around (1:1 × 10^-5Ω^-1cm^-1) at 300K. Thermoelectric power measurements of the film were carried out. Furthermore, the properties of these films are compared with properties of Cu2O obtained by other methods. 相似文献
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Numerical calculations of the effect of laser irradiance was performed for three homogeneous slabs. The temperature profile and the temperature of the front surface for three metals, silver, steel, and aluminium was calculated. The formulation of the temperature distribution of the slab was carried out using Fourier series expansions for the case of time dependent laser irradiance. The exact expressions for the thermal penetration depth and the critical time required to initiate melting (i.e. damage) were found. 相似文献
96.
Justyna Płotka-Wasylka Heba M. Mohamed Aleksandra Kurowska-Susdorf Rajkumar Dewani Michel Y. Fares Vasil Andruch 《Current Opinion in Green and Sustainable Chemistry》2021
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97.
Journal of Cluster Science - The effective entrapment of drugs into nanoparticles is one of the most important features during nanoparticles preparation. The percentage loaded drug into the... 相似文献
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Heba A. Gaballa Luke M. Geever John A. Killion Clement L. Higginbotham 《Journal of Polymer Science.Polymer Physics》2013,51(21):1555-1564
Physically crosslinked hydrogels based on N‐vinylcaprolactam/acrylic acid and N‐vinylcaprolactam/methacrylic acid were prepared via free radical polymerization. These temperature responsive hydrogels were characterized in terms of glass transition, phase separation temperature, potentiometric titration and swelling properties. Results showed that phase transition temperature was dependent on the pH value of the solution; increasing pH led to higher lower critical solution temperature (LCST) values which was related to the dissociative behaviors of the carboxylic group of MAc in the buffered solutions. Additionally, with the incorporation of N,N‐dimethylacrylamide into the system, cloud point measurements and MDSC showed an increased in the LCST. This increase was based on hydrophilicity, the hydrophilic–hydrophobic balance was disturbed, and consequently, the LCST behavior was shifted. The pKa of the copolymers ranged between 5.6 and 6.5, while for the terpolymers pKa ranged between 5.3 and 6. At high pH (>10), the ? COOH group is deprotonated and negatively charged (? COO?), while at low pH (1–3) the carboxylic group remains protonated which results in hydrogen bonding between the hydroxyl groups (from NaOH) and the excess of HCl. These results correlate with swelling studies where above the pKa value the hydrogels dissolved rapidly compared to below pKa they did not dissolve at all. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2013 , 51, 1555–1564 相似文献