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81.
ABSTRACT

BODIPY azine bearing chemosensor R1 has been synthesised for selective detection of Al3+with visual colour change from red-purple to purple and photo-physical studies were explained through Förster Resonance Energy Transfer (FRET) mechanism. Chemosensor showed good sensing capability with high binding constant and lower Limit of Detection (LOD) towards Al3+. Cell viability and fluorescence microscopic experiments illustrated about the cytocompatibily of the sensor in presence of Al3+ in living cells (MCF-7).  相似文献   
82.
Abstract

Replacement reactions of bis(diethyldithiocarbamato)antimony(III) chloride have been carried out with oxygen and sulfur donor ligands such as disodium oxalate, sodium acetate, sodium salicylate, benzoic acid, thioglycolic acid, acetylacetone, thiphenol, ethane-1,2-dithiol, and 2,2-dimethylpropane-1,3-diol to give mixed bis(diethyldithiocarbamato)antimony(III) derivatives of the corresponding ligands. These derivatives have been characterized by the physicochemical [melting point and molecular weight determination, elemental analysis (C, H, N, S, and Sb)], spectral [FT-IR, far-IR, NMR (1H and 13C)], ESI-mass, powder XRD, and SEM studies.

[Supplementary materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements for the following free supplemental files: Additional figures and tables]  相似文献   
83.
Abstract

Seven complexes of type [(C4H9i-O)2PS2]2SbR have been synthesized by the reaction of chlorobis(diisobutyldithiophosphato)antimony(III) with mixed thio and/or oxo donor ligands in 1:1?M stoichiometry, where R?=?SC6H5, OOCC6H5, SCH2COOH, SOCCH3, OOCCH3, SC6H4COOH and OOC(OH)C6H4. These newly synthesized derivatives have been characterized by different physicochemical (elemental analysis (C, H, S, Sb), melting point, molecular weight determination), spectral (UV, IR, NMR (1H, 13C and 31P)) studies, as well as ESI mass, thermal, powder XRD and biological studies. In the final step of weight loss in thermogravimetric analysis, occurring in the range of 245–505?°C, the degradation of the C6H3CO moieties takes place and antimony sulfide (1/2?Sb2S3) is obtained as remaining material, which is useful in various aspects. Bonded to antimony the diisobutyldithiophosphato substituent behaves as an anisobidentate ligand, which is confirmed through spectral analysis. Powder XRD studies indicate that these compounds crystallize in a monoclinic crystal system with an unit cell volume of ~7074–7162 Å3 forming nano ranged (9.69–15.69?nm) crystallites. From the antimicrobial screening tests, bis(diisobutyldithiophosphato)antimony(III) thioglycolate (compound 3) has shown a maximum zone of inhibition (19?mm) against E. coli at 200?μg mL?1 concentration.  相似文献   
84.
In this work, anatase titanium dioxide (TiO2) nanorods (NRs) were synthesized by low-temperature hydrolysis of titanium tetraisopropoxide (TTIP) and using oleic acid (OA) as capping agent. The OA-capped titania NRs were then processed using surface ligand exchange by pyridine (Py). The two types of NRs, with different capping agents hence obtained, were blended with poly[2-methoxy-5-(2′-ethyl-hexyloxy)-l,4-phenylene vinylene] (MEHPPV) to prepare hybrid organic–inorganic nanocomposites. In order to elucidate the changes caused by the surface modifications, transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), and X-ray diffraction were used to study the morphology. The Fourier transform infrared spectroscopy (FTIR) analysis confirms that the ligands coordinated with the Ti center of TiO2 NRs. The optical properties of the modified TiO2 NRs are characterized by UV–Vis absorption spectra and photoluminescence (PL) spectra. Photoluminescence lifetime studies were conducted to predict the capping agent more suitable for photovoltaic applications.  相似文献   
85.
A pulsed wire method is described for undulator field measurement. The results of the second field integral are compared with Hall probe results. The pulsed wire data are taken at different locations of the sensor along the length of the wire and with different gap of the undulator. A planar undulator with six periods is used in the pulsed wire set up. The total length of the undulator is 30 cm. The pulsed wire result shows good agreement with the Hall probe data.  相似文献   
86.
In this paper, we attempt to study the structure of multiplicative Lie algebras, the theory of extensions, the second cohomology groups of multiplicative Lie algebras, and in turn the Schur multipliers. The Schur–Hopf formula is established for multiplicative Lie algebras. We also introduce the group of nontrivial relations satisfied by the Lie product in a multiplicative Lie algebra, and study it as a functor arising from the presentations of multiplicative Lie algebras. Some applications in K-theory are also discussed.  相似文献   
87.
This review focuses on our work on metal‐free sensitizers for dye‐sensitized solar cells (DSSCs). Sensitizers based on D?A′?π?A architecture (D is a donor, A is an acceptor, A′ is an electron‐deficient entity) exhibit better light harvesting than D?π?A‐type sensitizers. However, appropriate molecular design is needed to avoid excessive aggregation of negative charge at the electron‐deficient entity upon photoexcitation. Rigidified aromatics, including aromatic segments comprising fused electron‐excessive and ‐deficient units in the spacer, allow effective electronic communication, and good photoinduced charge transfer leads to excellent cell performance. Sensitizers with two anchors/acceptors, D(–π–A)2, can more efficiently harvest light, inject electrons, and suppress dark current compared with congeners with a single anchor. Appropriate incorporation of heteroaromatic units in the spacer is beneficial to DSSC performance. High‐performance, aqueous‐based DSSCs can be achieved with a dual redox couple comprising imidazolium iodide and 2,2,6,6‐tetramethylpiperidin‐N‐oxyl, and/or using dyes of improved wettability through the incorporation of a triethylene oxide methyl ether chain.

  相似文献   

88.
A diverse range of novel and highly functionalized flavonoid-based tanaproget hybrids were synthesized and evaluated in vitro for their antimicrobial and antiproliferative activities. Novel products were synthesized in good yields (81–95%) under Pd-catalyzed reaction from bromo flavones and tanaproget boronic acids within 18–20 min at 60 °C. Bioassay results exhibited excellent activities against both hormone-dependent and hormone-independent human breast cancer cells (MCF-7, MDA-MB-231, DU-145, PC-3, and HeLa). Among them, compounds 4e, 9a, 9c, 9e, 9 g, 9 h, 9 m, and 9n displayed excellent activity. Compounds 4d, 4o, and 9o were found equally potent against C. albicans compared to fluconazole. Compound 5c showed better antibacterial activity against S. aureus. Compounds 5a, 9i, 9o, and 10c have shown admirable antibacterial activity against E. coli.  相似文献   
89.
90.
We propose a micromixer for obtaining better efficiency of vortex induced electroosmotic mixing of non-Newtonian bio-fluids at a relatively higher flow rate, which finds relevance in many biomedical and biological applications. To represent the rheology of non-Newtonian fluid, we consider the Carreau model in this study, while the applied electric field drives the constituent components in the micromixer. We show that the spatial variation of the applied field, triggered by the topological change of the bounding surfaces, upon interacting with the non-uniform surface potential gives rise to efficient mixing as realized by the formation of vortices in the proposed micromixer. Also, we show that the phase-lag between surface potential leads to the formation of asymmetric vortices. This behavior offers better mixing performance following the appearance of undulation on the flow pattern. Finally, we establish that the assumption of a point charge in the paradigm of electroosmotic mixing, which is not realistic as well, under-predicts the mixing efficiency at higher amplitude of the non-uniform zeta potential. The inferences of the present analysis may guide as a design tool for micromixer where rheological properties of the fluid and flow actuation parameters can be simultaneously tuned to obtain phenomenal enhancement in mixing efficiency.  相似文献   
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