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81.
A series of new andrographolide‐1,2,3‐triazole derivatives, 3a , 3b , 3c , 3d , 3e , 3f , 3g , 3h , 3i , 3j , 3k , were synthesized from a natural bioactive labdane type diterpenoid, andrographolide. All the derivatives were screened against human cancer cell lines MCF7, MDA‐MB‐231, COLO205, HepG2, K562, Hela, and HEK293 to evaluate their cytotoxic activity. All the compounds showed anticancer activity selectively against K562 cell line, with IC50 values ranging from 8.00 to 17.11 µM, and are inactive against the rest of the cell lines. Compounds 3c and 3d showed significant cytotoxicity among the synthesized derivatives. The in silico docking studies revealed compounds 3b and 3d with high binding affinity against the cancer target, transient receptor potential vanilloid 1.  相似文献   
82.
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   
83.
84.
In the present frame of work, Macrophomina phaseolina is encapsulated in silica matrices at various concentrations by low temperature sol-gel technique using tetraethylorthosilicate (TEOS) as precursor. The optical and photophysical properties of these samples have been studied by second harmonics of Nd:YAG laser at 532 nm. UV-visible absorption spectra of samples have been recorded and it is found that the absorption increases with increase in concentration of fungus. Further, a decrease in output transmission intensity of the laser has been observed with increase in fungus concentration. The temporal response of these samples has also been examined. The results show that the fungus concentration can be measured within ∼15–20 min. This method of optical sensing of fungus in test sample is faster than other techniques, such as the conventional colorimetric method which takes about 1 h.  相似文献   
85.
Two binary phase diagrams of the liquid crystals (4-n-pentylphenyl-4-n-hexyloxybenzoate (PPHB) with 4-nitrophenyl-4-n-pentylbenzoate (NPPB) and 4-n-hexyloxyphenyl-4-n-decyloxybenzoate (HPDB) with NPPB) have been studied. PPHB shows only a nematic phase where as for HPDB trimorphism, with the SmC, SmA and nematic phases, was observed. Substance NPPB which has a strong polar nitro group is non-mesogenic one. Both the phase diagrams show an induction and stabilization of SmA phase and appearance of the nematic state in the high concentration range of polar component. The dielectric measurements confirm the phase transition temperatures and show changes in the short range interaction at the phase transitions.  相似文献   
86.
Strong blue-green light emitting Eu doped SrAl2O4 phosphor was synthesized by a low-temperature initiated, self-propagating and gas producing combustion process in a very short time (<5 min). The prepared powder was characterized by X-ray diffraction, Fourier-transform infrared spectrometry and scanning electron microscopy. The excitation spectrum shows a peak at 397 nm. Upon excitation at 397 nm, the emission spectrum exhibits a well defined broad band with maximum at 493 nm corresponding to 4f65d  4f7 transition. Electron paramagnetic resonance (EPR) measurements at X-band showed low field signals due to Eu2+ ions in SrAl2O4:Eu.  相似文献   
87.
We have reported the synthesis of cubic (zinc blende) phase ZnS: Ni2+ nanoparticles using a simple wet‐chemical method. Synthesized ZnS: Ni2+ nanoparticles had been characterized by X‐ray diffraction (XRD) and Energy Dispersive X‐ray (EDX) analysis. Surface morphologies were studied using Scanning Electron Microscopy (SEM). Fourier Transform Infrared (FTIR) spectra of selected samples were also carried out to confirm the presence of capping agent on the surface of the material. We have demonstrated that various morphologies like spherical, tetrapods, sheet and long‐armed multipods are emerged by simple chemical route without any vigorous reaction parameters and changing the concentration of dopant ions only. The probable mechanism for such morphologies has also been suggested.  相似文献   
88.
Trichloromethyl phenyl ketone benzoylates primary and secondary aliphatic alcoholic groups in compounds also containing a phenolic group in the presence of 2–10 mol % of PMDETA organocatalyst at room temperature in high yields and excellent selectivity. It also shows the potential to selectively benzoylate primary alcoholic groups of aminoarylalkanols and primary-secondary diols as well as primary amino group of alkyl amines in the presence of aryl amines under similar conditions. A rationale for the selectivity and efficiency of the reaction has been provided.  相似文献   
89.
The structural, electronic, elastic and bonding properties of four transition metal carbides, ScC, YC (group III), VC and NbC (group V), have been investigated systematically using the first principles density functional theory (DFT). The full potential linearized augmented plane wave (FP-LAPW) method with the generalized gradient approximation (GGA) for the exchange correlation has been used for the calculation of the total energy. The ground state properties, such as equilibrium lattice constant, bulk modulus, are computed and compared with theoretical and experimental data. The electronic and bonding patterns of the two groups of compounds have been analyzed quantitatively and compared with the available data. It is clear from band structures that all the four transition metal monocarbides are metallic in nature. Analysis of elastic constants reveals that the carbides of group III are ductile in nature while those of group V are brittle.  相似文献   
90.
Constabelian codes can be viewed as ideals in twisted group algebras over finite fields. In this paper we study decomposition of semisimple twisted group algebras of finite abelian groups and prove results regarding complete determination of a full set of primitive orthogonal idempotents in such algebras. We also explicitly determine complete sets of primitive orthogonal idempotents of twisted group algebras of finite cyclic and abelian p-groups. We also describe methods of determining complete set of primitive idempotents of abelian groups whose orders are divisible by more than one prime and give concrete (numerical) examples of minimal constabelian codes, illustrating the above mentioned results.  相似文献   
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