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排序方式: 共有748条查询结果,搜索用时 15 毫秒
131.
Priti Tagde Pooja Tagde Fahadul Islam Sandeep Tagde Muddaser Shah Zareen Delawar Hussain Md. Habibur Rahman Agnieszka Najda Ibtesam S. Alanazi Mousa O. Germoush Hanan R. H. Mohamed Mardi M. Algandaby Mohammed Z. Nasrullah Natalia Kot Mohamed M. Abdel-Daim 《Molecules (Basel, Switzerland)》2021,26(23)
Curcumin is the primary polyphenol in turmeric’s curcuminoid class. It has a wide range of therapeutic applications, such as anti-inflammatory, antioxidant, antidiabetic, hepatoprotective, antibacterial, and anticancer effects against various cancers, but has poor solubility and low bioavailability. Objective: To improve curcumin’s bioavailability, plasma concentration, and cellular permeability processes. The nanocurcumin approach over curcumin has been proven appropriate for encapsulating or loading curcumin (nanocurcumin) to increase its therapeutic potential. Conclusion: Though incorporating curcumin into nanocurcumin form may be a viable method for overcoming its intrinsic limitations, and there are reasonable concerns regarding its toxicological safety once it enters biological pathways. This review article mainly highlights the therapeutic benefits of nanocurcumin over curcumin. 相似文献
132.
We have studied the effect of a non-Hermitian Bosonic bath on the dynamics of a two-level spin system. The non-Hermitian Hamiltonian of the bath is chosen such that it converges to the harmonic oscillator Hamiltonian when the non-Hermiticity is switched off. We calculate the dynamics of the spin system and found that the non-Hermiticity can have positive as well as negative effects on the coherence of the system. However, the decoherence can be completely eliminated by choosing the non-Hermiticity parameter and the phase of the system bath interaction appropriately. We have also studied the effect of this bath on the entanglement of a two-spin system when the bath is acting only on one spin. 相似文献
133.
Madhukar N. Jachak Sandeep M. Bagul Bhausaheb K. Ghotekar Raghunath B. Toche 《Monatshefte für Chemie / Chemical Monthly》2009,140(6):655-662
Abstract A series of (2E)-3-(1-chloro-6-methoxy-3,4-dihydronaphthalen-2-yl)-1-(4-aryl)prop-2-en-1-ones (chalcones) have been synthesized by a new
synthetic route. The 3-pyridinecarbonitrile derivatives were synthesized by the Michael reaction of malononitrile (in base)
and aroylacetonitriles (in acid) with chalcones in one pot. The fluorescent properties and quantum yields of these compounds
were studied.
Graphical Abstract
相似文献
134.
Madhukar N. Jachak Sandeep M. Bagul Bhausaheb K. Ghotekar Raghunath B. Toche 《Monatshefte für Chemie / Chemical Monthly》2009,20(5):655-662
Abstract
A series of (2E)-3-(1-chloro-6-methoxy-3,4-dihydronaphthalen-2-yl)-1-(4-aryl)prop-2-en-1-ones (chalcones) have been synthesized by a new synthetic route. The 3-pyridinecarbonitrile derivatives were synthesized by the Michael reaction of malononitrile (in base) and aroylacetonitriles (in acid) with chalcones in one pot. The fluorescent properties and quantum yields of these compounds were studied. 相似文献135.
This communication describes formation of a 3N-coordinated silver-modified adenine metallamacrocyclic quartet in solid state, its aggregative ordering on graphite surface, and luminescence. 相似文献
136.
1-(2,2-Dichlorovinyl)benzotriazole (7) was prepared by the reaction of 1-formylbenzotriazole with PPh3/CCl4. Lithiation-substitution of 7 with electrophiles gave a variety of functionalized N-(ethynyl)benzotriazoles 8a-h in 32-84% yields. 相似文献
137.
Asuri P Karajanagi SS Yang H Yim TJ Kane RS Dordick JS 《Langmuir : the ACS journal of surfaces and colloids》2006,22(13):5833-5836
We have discovered a novel property of single-walled carbon nanotubes (SWNTs)-their ability to stabilize proteins at elevated temperatures and in organic solvents to a greater extent than conventional flat supports. Experimental results and theoretical analysis reveal that the stabilization results from the curvature of SWNTs, which suppresses unfavorable protein-protein lateral interactions. Our results also indicate that the phenomenon is not unique to SWNTs but could be extended to other nanomaterials. The protein-nanotube conjugates represent a new generation of active and stable catalytic materials with potential use in biosensors, diagnostics, and bioactive films and other hybrid materials that integrate biotic and abiotic components. 相似文献
138.
Ghumaan S Sarkar B Chanda N Sieger M Fiedler J Kaim W Lahiri GK 《Inorganic chemistry》2006,45(19):7955-7961
The tppz-bridged diruthenium(II) complex [(dpk)(Cl)Ru(II)(mu-tppz)Ru(II)(Cl)(dpk)](ClO4)2, [2](ClO4)2, and mononuclear [(dpk)(Cl)Ru(II)(tppz)](ClO4), [1](ClO4) [tppz = 2,3,5,6-tetrakis(2-pyridyl)pyrazine, dpk = 2,2'-dipyridylketone], have been synthesized. The 260 mV separation between successive one-electron oxidation couples in [2]2+ translates to a relatively small comproportionation constant, Kc, of 2.5 x 10(4) for the intermediate. It is shown how electrochemical data (E(ox), E(red), Kc) reflect the donor/acceptor effects of ancillary ligands L in a series of systems [(L)ClRu(mu-tppz)RuCl(L)]n, particularly the competition between L and tppz for electron density from the metal. According to EPR (g1 = 2.470, g2 = 2.195, and g3 = 1.873 at 4 K) the intermediate [2]3+ is a mixed-valent Ru(II)Ru(III) species which shows a rather narrow intervalence charge transfer (IVCT) band at 1800 nm (epsilon = 1500 M(-1) cm(-1)). The width at half-height (Deltanu(1/2)) of 700 cm(-1) of the IVCT band is much smaller than the calculated value of 3584 cm(-1), obtained by using the Hush formula Deltanu(1/2) = (2310E(op))(1/2) (E(op) = 5556 cm(-1), energy of the IVCT transition) which would be applicable to localized (Class II) mixed-valent Ru(II)Ru(III) systems. Valence delocalization in [2]3+ is supported by the uniform shift of the nu(C=O) band of the N,N'-coordinated dpk ligands from 1676 cm(-1) in the Ru(II)Ru(II) precursor to 1690 cm(-1) in the Ru(2.5)Ru(2.5) form, illustrating the use of the dpk acceptor to act as reporter ligand via the free but pi-conjugated organic carbonyl group. The apparent contradiction between the moderate value of Kc and the narrow IVCT band is being discussed considering "borderline" or "hybrid" "Class II-III" concepts of mixed-valency, as well as coordination aspects, i.e., the bis-tridentate nature of the pi-acceptor bridging ligand. Altogether, the complex ions [1]+ and [2]2+ display four and five successive reduction processes, respectively, involving both tppz- and dpk-based unoccupied pi orbitals. The one-electron reduced form [2]+ has been assigned as a tppz*- radical-anion-containing species which exhibits a free-radical-type EPR signal at 4K (g(parallel) = 2.002, g(perpendicular) = 1.994) and one moderately intense ligand-based low-energy band at 965 nm (epsilon = 1100 M(-1) cm(-1)). 相似文献
139.
Self-organization of disc-like molecules: chemical aspects 总被引:2,自引:0,他引:2
Kumar S 《Chemical Society reviews》2006,35(1):83-109
The hierarchical self-assembly of disc-shaped molecules leads to the formation of discotic liquid crystals. These materials are of fundamental importance not only as models for the study of energy and charge migration in self-organized systems but also as functional materials for device applications such as, one-dimensional conductors, photoconductors, light emitting diodes, photovoltaic solar cells, field-effect transistors and gas sensors. The negative birefringence films formed by polymerized nematic discotic liquid crystals have been commercialized as compensation foils to enlarge the viewing angle of commonly used twisted nematic liquid crystal displays. To date the number of discotic liquid crystals derived from more than 50 different cores comes to about 3000. This critical review describes, after an in-depth introduction, recent advances in basic design principles and synthetic approaches towards the preparation of most frequently encountered discotic liquid crystals. 相似文献
140.
Sandeep Aashish Abhilash Padhy Sukanta Panda Arun Rana 《The European Physical Journal C - Particles and Fields》2018,78(11):887
We investigate the possibility of inflation with models of antisymmetric tensor field having minimal and nonminimal couplings to gravity. Although the minimal model does not support inflation, the nonminimal models, through the introduction of a nonminimal coupling to gravity, can give rise to stable de-Sitter solutions with a bound on the coupling parameters. The values of field and coupling parameters are sub-planckian. Slow roll analysis is performed and slow-roll parameters are defined which can give the required number of e-folds for sufficient inflation. Stability analysis has been performed for perturbations to antisymmetric field while keeping the metric unperturbed, and it is found that only the sub-horizon modes are free of ghost instability for de-Sitter space. 相似文献