348 research outputs found

    Thermodynamics Approach in the Adsorption of Heavy Metals

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    Design of Fullerene20-thieno[2,3-c]pyrrole-4,6(5H)-dione-fullerene20 for Opto-nonlinear applications: Quantum Mechanical Study

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    Background: Many organic compounds are studied because of their nonlinear optical properties, which are crucial in photonics, optical switches, modulators, optical data storage, and other devices that use light to transport information. In experimental and theoretical researches, nonlinear optical phenomena, primarily resulting from interactions between matter and strong electric fields, have received considerable attention. Materials like these have numerous applications in science, engineering, and technology. Materials and Methods: Fullerene 20 has been adopted as an electron donor, which was considered an NLO molecular material, while the thieno[2,3-c]pyrrole-4,6(5H)-dione has been adopted as an electron acceptor. Fullerene20-thieno[2,3-c]pyrrole-4,6(5H)-dione-fullerene20 (FTPDF), as D-A-D, has been designed for nonlinear optical applications. Fullerene20-thieno[2,3-c]pyrrole-4,6(5H)-dione-fullerene20 (FTPDF) was studied to determine its linear and nonlinear optical properties. For FTPDF, nonlinear optical properties were calculated with DFT/B3LYP using the basis set 6-31G(d,p). Various quantum calculations determine the structural and symmetry properties of Fullerene20-thieno[2،3-c]pyrrole-4،6(5H)-dione-fullerene20. Results: The rotation increases the electric dipole moment µtot, average linear polarizability αo and the first hyperpolarizability βtot. And the anisotropic polarizability ∆α is smaller than the average polarizability, and the present structure has few deviations from spherical symmetry. FTPDF shows µx-switch behavior. In particular, the rotation can raise the possibility for a new type of molecular βx-switch. Conclusion: The Highest Occupied Molecular Orbital (HOMO) and the Lowest Unoccupied Molecular Orbital (LUMO) energies estimated by DFT for the investigated molecules have been reported here. Fullerene20-thieno[2,3-c]pyrrole-4,6(5H)-dione-fullerene20 has an increased first hyperpolarizability, making it a novel material suitable for the development of optoelectronic devices

    Ozone treatment of aqueous solutions containing commercial dyes

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    Degradation by ozone and biodegradability were studied for two different families of non-biodegradable textile dyes(reactive dyes and direct dyes). 95% of color removal ofdye solutions was achieved with ozone dose of 2.5 ppm. However, ozone requirements for reactive dyes degradation were less than that of direct dyes for the same color removal level. Five days biological oxygen demand (BOD5) was found to increase during discoloration process while chemical oxygen demand (COD) decreased. The biodegradability index (BOD5/COD) increased up to 0.40 for most of the dye solutions when total discoloration was obtained. It implies that ozonation tends to enhance the biodegradability of solutions contain dye. Thus, this technique could be used as a pre-treatment step for conventional biological treatment of water-containing commercial dyes. The degradation of dyes by direct ozonation was well-represented by pseudo-first order kinetics

    Teorijsko ab initio proučavanje učinaka električnog polja na građu i stabilnost baznog para G:C

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    The effect of applied external electric field on DNA occurs mostly at high field intensity. The results of a theoretical ab initio study of effects of applied electric field on G:C base pair components are reported. The geometries of the local minima were optimized without the symmetry restrictions by the gradient procedure at density-functional level of the theory and were verified by calculations of the second derivative of energy. The standard CEP-31G basis set was used. The geometrical parameters, relative stability and interaction energies are reported. The electric field mutation could be classified as a multi-point mutation.Učinak vanjskog električnog polja na DNA javlja se najčešće za jaka polja. Izvješćujemo o ishodima proučavanja učinaka vanjskog električnog polja na sastavnice baznog para G:C polazeći od osnova teorije. Razmještaj lokalnih minimuma smo optimizirali bez ograničenja na uvjete simetrije rabeći gradijentan postupak na razini teorije funkcionala gustoće i provjerili računima drugih derivacija energije. Primijenili smo uobičajen osnovni skup CEP-31G. Izvješćujemo o promjenama razmaka, stabilnosti i energijama međudjelovanja. Mutacije električnim poljem mogle bi se razvrstati u višemjesne mutacije

    Coarse-Grained Models of Biological Membranes within the Single Chain Mean Field Theory

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    The Single Chain Mean Field theory is used to simulate the equilibrium structure of phospholipid membranes at the molecular level. Three levels of coarse-graining of DMPC phospholipid surfactants are present: the detailed 44-beads double tails model, the 10-beads double tails model and the minimal 3-beads model. We show that all three models are able to reproduce the essential equilibrium properties of the phospholipid bilayer, while the simplest 3-beads model is the fastest model which can describe adequately the thickness of the layer, the area per lipid and the rigidity of the membrane. The accuracy of the method in description of equilibrium structures of membranes compete with Monte Carlo simulations while the speed of computation and the mean field nature of the approach allows for straightforward applications to systems with great complexity.Comment: Accepted for publication in Soft Matte

    Design, Synthesis, and Biological Evaluation of Indole-2-carboxamides as Potential Multi-Target Antiproliferative Agents

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    Funding Information: The author acknowledge the support by Princess Nourah Bint Abdulrahman University Researchers Supporting Project Number (PNURSP2023R3), Princess Nourah bint Abdulrahman University, Riyadh, Saudi Arabia.Peer reviewedPublisher PD

    Polycyclic Aromatic Hydrocarbons in Some Fishes from the Iraqi Marine Waters

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    This study represent the concentrations of 16 PAHs in 12 of commercial fish species (Euryglossa orientalis , Acanthopagrus araticus , Epinephelus coioides , Chirocentrus dorab , Scomberoidescommersonnianus , Scomberoides lysan , Otolithes ruber , Alepes diedaba , Tenualosa ilisha , Parastromateus niger , Pampus  argentetus , Ablennws hians ) . which were collected from the coastal area of the of Iraqi marine water during 2015. The analysis of Polycyclic Aromatic Hydrocarbons (PAHs) in fish muscles were determined using HPLC to identify the sources of PAHs, The total concentration of PAHs in fishes ranged between (0.432) ng/g dry weight in P. niger and (14.939) ng/g dry weight in  T. ilisha muscles . When we calculated the ratio of (Flouranthene to Pyrene)  and the ration of (Phenanthrene to Anthracene) and ratio of low molecular weight to high molecular weight of PAHs and the ration of Anthracene to (Anthracene + Phenanthrene ) and the ration of Benzo[a]anthracene to (Benzo[a]anthracene+ Chrysene), it is showed that the PAHs origin in fishes were Pyrogenic and Petrogenic . T. ilisha showns high ability to accumulate PAHs compounds  like Fluorene , Anthracene, Acenaphthene and Phenanthrene in muscles compared with other fishes ,  there was different ability of fish to accumulate  the PAHs from surrounded environments  . Keywords: PAHs compounds, HPLC, fishes, Iraqi marine water

    Design, Synthesis, and Antiproliferative Activity of New 5-Chloro-indole-2-carboxylate and Pyrrolo[3,4-b]indol-3-one Derivatives as Potent Inhibitors of EGFRT790M/BRAFV600E Pathways

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    Funding Information: This work was funded by Princess Nourah bint Abdulrahman University Researchers Supporting Project Number (PNURSP2023R3), Princess Nourah bint Abdulrahman University, Riyadh, Saudi Arabia.Peer reviewedPublisher PD

    Nursing Perspectives on the Association between Human Capital Development and the Work Engagement: A Cross-Sectional Study

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    This study examined the impact of human capital development on the nurses’ work engagement. A questionnaire was adapted and distributed to a nursing convenience sample in different types of hospitals. The sample size was 286 male and female nurses who completed it. Structural Equation Modelling (SEM) was used to test the research hypothesis. Results revealed that human capital development had a direct impact on the nursing work engagement. Nursing work engagement give managers ability to improve the work environment, increase the work professional and institutional loyalty. Supporting the human capital development tools is very important for any healthcare organization
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