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121.
In this research, a novel KIT-5/Bi2S3-Fe3O4 nanocomposite was prepared. The structure and morphology properties of the nanocomposite were well characterized by XRD, FESEM-EDS-mapping, TEM, and N2 adsorption–desorption. Benefiting from the visible light, the as-prepared KIT-5/Bi2S3-Fe3O4 nanocomposite exhibit significantly improved photocatalytic performance for the degradation of parathion. The optimum photocatalytic efficiency of KIT-5/Bi2S3-Fe3O4 nanocomposite was investigated with the central composite design using Design Expert software. The four critical variables affecting parathion degradation such as the concentration of parathion, pH, irradiation time, and amount of KIT-5/Bi2S3-Fe3O4 nanocatalyst. A polynomial function corresponding to degradation percent was obtained for the experimental data. The results showed that this catalyst has a good performance for the degradation of parathion. 相似文献
122.
Ehab M. Abdalla Laila H. Abdel Rahman Antar A. Abdelhamid Mohamed R. Shehata Asma A. Alothman Ayman Nafady 《应用有机金属化学》2020,34(11):e5912
Although salens and imidazoles are well-studied motifs among bioactive and therapeutic agents, their properties when combined in transition metal complexes are not well developed. To explore the structure/reactivity of this class of compounds, a salen-based ligand, namely (2,2′-{1,2-ethanediylbis[nitrilo(E)methylylidene]}diphenol, S), and its binary (MS) and ternary (MSI) complexes (I = imidazole; M = Co (II), Ni (II), Cu (II), Cd (II), Al (III), and La (III)) have been synthesized and fully characterized by standard physicochemical and theoretical methods. Evidence from structural analysis tools along with DFT modeling revealed an unusual monobasic tridentate salen binding mode, involving the phenolic oxygen, the nitrogen of the azomethine group, and NH group formed via phenol-to-cyclohexadienone tautomerization, giving rise to a general molecular formula of MSI complexes as [M(S)(I)2(Cl)] for M (II) = Co, Ni, Cu and Cd or [M(S)(I)(Cl)2] for M (III) = Al and La, respectively. The antimicrobial activities of S, MS, and MSI were screened against several bacterial and fungal strains. Of all tested complexes, CdS and CuSI were the most effective antimicrobials, giving larger inhibition zones than the reference antibiotics. The antimicrobial efficacy for the MS complexes follows the order: CdS > gentamicin > CuS > NiS > CoS > LaS > AlS > S, whereas MSI complex, potencies are ordered as CuSI > gentamicin > CdSI >NiSI > CoSI > LaSI > AlSI > S. In vitro cytotoxicity screening of MSI complexes disclosed that both CuSI and CdSI exhibited higher activity against human liver (Hep-G2) and breast (MDA-MB231) carcinoma cell lines than the reference (cisplatin) drug. The satisfactory bioactivities observed for several of these compounds supports the underlying design idea for combining important bioactive motifs for possible therapeutic benefit. 相似文献
123.
Slow Relaxation of Magnetization in an Isostructural Series of Zinc–Lanthanide Complexes: An Integrated EPR and AC Susceptibility Study
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Dr. Asma Amjad Dr. Augustin M. Madalan Prof. Dr. Marius Andruh Prof. Dr. Andrea Caneschi Prof. Dr. Lorenzo Sorace 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(36):12849-12858
We report the synthesis, structure, and spectroscopic and dynamic magnetic properties of a series of heterodinuclear complexes, [ZnLn(LH4)2](NO3)3 ? 6 H2O (Ln=Nd, Tb, Dy, Ho, Er, and Yb), with the singly deprotonated form of a new compartmentalized Schiff‐base ligand, LH5. The LnIII ions in these systems show a distorted square‐antiprism geometry with an LnO8 coordination sphere. EPR spectroscopy and DC magnetic studies have shown that the anisotropic nature of the complexes is far more complicated than predicted on the basis of a simple electrostatic model. Among the investigated systems, only the DyIII derivative showed single‐ion magnet behavior, in zero and an applied magnetic field, both in pure polycrystalline samples and in a series of polycrystalline samples with different degrees of dilution at the single‐crystal level in the isostructural YIII derivative. The rich dynamics observed as functions of frequency, field, and temperature reveals that multiple relaxation mechanisms are at play, resulting in a barrier of 189 cm?1, which is among the highest reported for a dinuclear Zn–Dy system. Analysis of the dynamic behavior as a function of dilution degree further evidenced the persistence of non‐negligible intermolecular interactions, even at the lowest concentration of 1 %. 相似文献
124.
125.
M. Asma A. Bansal W. A. M. Othman B. R. Wong A. Biswas 《Physics of Wave Phenomena》2018,26(4):312-316
Here, optical soliton perturbation with quadratic-cubic nonlinearity has been discussed by applying Lie symmetry and group invariants. The perturbation terms include third and fourth order dispersions in addition to self-steepening, intermodal dispersion and higher order dispersion effects. Using presented algorithms, Bright and dark soliton solutions are revealed. 相似文献
126.
127.
Dr. Ruohu Zhang Prof. Dr. Zhuyuan Wang Dr. Chunyuan Song Dr. Jing Yang Dr. Jin Li Dr. Asma Sadaf Prof. Dr. Yiping Cui 《Chemphyschem》2011,12(5):992-998
A new and simple procedure to enhance the fluorescence of analytes on the surfaces of a solid substrate is demonstrated based on Ag@SiO2 nanoparticles. Two kinds of silver–silica core–shell nanoparticles with shell thicknesses of around 3 and 15 nm have been prepared and used as enhancing agents, respectively. By simply pipetting drops of the enhancing agents onto substrate surfaces with Rose Bengal monolayers, an enhancement of about 27 times, compared with the control sample, is achieved by using the Ag@SiO2 nanoparticles with shells of about 3 nm, whereas an enhancement of around 11.7 times is obtained when using those with thicker shells. The effects of shell thickness and surface density of the enhancing agents on the enhancement have been investigated experimentally. The results show that this method can be potentially helpful in fluorescence‐based surface analysis. 相似文献
128.
Marzouk A Danset D Zhou MF Gong Y Alikhani ME Manceron L 《The journal of physical chemistry. A》2011,115(32):9014-9021
The formation and structure of a novel species, a disuperoxo-cobalt dioxide complex (CoO(6)), has been investigated using matrix isolation in solid neon and argon, coupled to infrared spectroscopy and by quantum chemical methods. It is found that CoO(6) can be formed by successive complexation of cobalt dioxide by molecular oxygen without activation energy by diffusion of ground state O(2) molecules at 9K in the dark. The IR data on one combination and seven fundamentals, isotopic effects, and quantum chemical calculations are both consistent with an asymmetrical structure with two slightly nonequivalent oxygen ligands complexing a cobalt dioxide subunit. Evidence for other, metastable states is also presented, but the data are not complete. The electronic structure and formation pathway of this unique, formally +VI oxidation state, complex has been investigated using several functionals of current DFT within the broken-symmetry unrestricted formalism. It has been shown that the M06L pure local functional well reproduce the experimental observations. The ground electronic state is predicted to be an open shell (2)A' doublet with the quartet states above by more than 9 kcal/mol and the sextet lying even higher in energy. The ground state has a strong and complex multireference character that hinders the use of more precise multireference approaches and requires caution in the methodology to be used. The geometrical, energetic, and vibrational properties have been computed. 相似文献
129.
Asma Mihandoust Nahid Maleki-Jirsaraei Shahin Rouhani Shahabeddin Safi Majid Alizadeh 《Electrophoresis》2020,41(5-6):353-359
The inertial microfluidic technique, as a powerful new tool for accurate cell/particle separation based on the hydrodynamic phenomenon, has drawn considerable interest in recent years. Despite numerous microfluidic techniques of particle separation, there are few articles in the literature on separation techniques addressing external outlet geometry to increase the throughput efficiency and purity. In this work, we report on a spiral inertial microfluidic device with high efficiency (>98%). Herein, we demonstrate how changing the outlet geometry can improve the particle separation throughput. We present a complete separation of 4 and 6 μm from 10 μm particles potentially applicable to separate microalgae (Tetraselmis suecica from Phaeodactylum tricornutum). Two spiral microchannels with the same cross section dimension but different outlet geometry were considered and tested to investigate the particle focusing behavior and separation efficiency. As compared with particle focusing observed in channels with a simple outlet, the particle focusing in a modified outlet geometry appears in a more successful focusing manner with complete separation. This simple approach of particle separation makes it attractive for lab-on-a-chip devices for continuous extraction and filtration of a wide range of cell/particle sizes. 相似文献
130.
Manju Nagaraja Balakrishna Kalluraya Asma Tharangini K. Shreekanth Madan S. Kumar 《Journal of heterocyclic chemistry》2020,57(10):3642-3652
A new class of functionalized pyrazole bearing 1,2,3-triazole has been synthesized via Cu(I) mediated 1,3-dipolar cycloaddition of pyrazole bearing azide with various aromatic/heteroaromatic bearing terminal dipolarophile (acetylene). Structures of the newly synthesized compounds were explicated by analytical and spectral analysis. All the newly synthesized compounds were evaluated for their in-vitro antibacterial and antioxidant activity. Among the synthesized compound, triazole bearing 2,5-thiazolidinone 5b (20 ± 0.70) and triazole bearing thiocarboamide 5e (19 ± 0.70) showed good antibacterial activity against Escherichia coli and Pseudomonas aeruginosa, respectively. The newly synthesized compounds further tested for their ability to bleach DPPH radical using DPPH scavenging assay. Among the synthesized compounds 1,2,3-triazole bearing 2,5-thiazolidinone 5b (58.81%) exhibited good DPPH scavenging activity compared to the rest of the compounds. From the X-ray and Hirshfield analysis, it was observed that compound 3 , crystallizes in a triclinic crystal system with a P-1 space group. The major intercontacts present in these molecules are H…H (39.7%), C…H (23.9%), N…H (20.3%). 相似文献