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91.
Molecular Diversity - This study describes the use of 3-aminotriazole, different aldehydes and N-methyl-1-(methylthio)-2-nitroethenamine as a ketene N,S-acetal in a three-component condensation for... 相似文献
92.
Mohammad Akbar Ali Ai Ling Tan Aminul Huq Mirza Jose H. Santos Aimi Hanisah Bte Hj Abdullah 《Transition Metal Chemistry》2012,37(7):651-659
Four tridentate ONS ligands, namely 2-hydroxyacetophenonethiosemicarbazone (H2L1), the 2-hydroxyacetophenone Schiff base of S-methyldithiocarbazate (H2L2), the 2-hydroxy-5-nitrobenzaldehyde Schiff base of S-methyldithiocarbazate (H2L3), and the 2-hydroxy-5-nitrobenzaldehyde Schiff base of S-benzyldithiocarbazate (H2L4), and their complexes of general formula [Ni(HL1)2], [ML] (M?=?NiII or CuII; L?=?L1, L2, L3 and L4), [Co(HL)(L); L?=?L1, L2, L3 and L4] and [ML(B)] (M?=?NiII or CuII; L?=?L2 and L4; B?=?py, PPh3) have been prepared and characterized by physico-chemical techniques. Spectroscopic evidence indicates that the Schiff bases behave as ONS tridentate chelating agents. X-ray crystallographic structure determination of [NiL2(PPh3)] and [CuL4(py)] indicates that these complexes have an approximately square-planar structure with the Schiff bases acting as dinegatively charged ONS tridentate ligands coordinating via the phenoxide oxygen, azomethine nitrogen and thiolate sulfur atoms. The electrochemical properties of the complexes have been studied by cyclic voltammetry. 相似文献
93.
In this paper we have considered a red-shift based linear correction in derivative of action in the context of vacuum f (R) gravity. Here we have found out that the linear correction may describe the late time acceleration which is appeared by
SuperNovae Ia with no need of dark energy. Also we have calculated the asymptotic action for the desired correction. The value
of all solutions may reduce to de’ Sitter universe in the absence of correction term. 相似文献
94.
Solmaz Aliyeva 《中国化学会会志》2020,67(11):2071-2081
This paper presents an analysis of adsorption of acridine yellow G (AYG) from aqueous solutions through the use of functionalized grapheme nanoplatelets/modified polybutadiene hybrid composite (FGNPs/MPB). The adsorption of AYG onto FGNPs/MPB was investigated based on the AYG concentration, pH, contact time, temperature, and adsorbent dose. A maximum adsorption capacity was obtained at a pH of 7 (23.7 mg/g), an adsorbent dose of 1.0 g/L (20.8 mg/g), and an initial AYG concentration of 28.5 mg/L (16.9 mg/g). The value of qe of FGNPs/MPB increases with an increase in temperature from 293 to 323 K. Equilibrium isotherm data were analyzed using the Langmuir and Freundlich isotherm models. The Langmuir model best describes the adsorption processes of AYG, which showed that the monolayer adsorption capacity of FGNPs/MBP is 22.9 mg/g. The pseudofirst-order, pseudosecond-order, and intraparticle diffusion models were used to study the kinetics of the AYG adsorption onto FGNPs/MPB. The pseudosecond-order model better described kinetic data for the adsorption of AYG onto FGNPs/MPB. Thermodynamic parameters, such as the Gibbs free energy, enthalpy, and entropy, indicated that the AYG adsorption onto FGNPs/MPB was spontaneous feasible, and endothermic. 相似文献
95.
Nahid Nishat Shahnawaz Ahmad Bhat Abdul Kareem Swati Dhyani Abdulrahman Mohammad Azar Ullah Mirza 《Journal of inclusion phenomena and macrocyclic chemistry》2018,92(3-4):395-409
Macro-cyclic ligands from adipic acid, ethylenediamine with diethyloxalate and diethylmalonate and their respective metal complexes of Mn(II), Co(II), Ni(II), Cu(II), and Zn(II) with macro cyclic ligands (LO) and (LM) L [N,N′-bis(2-aminoethyl)hexanediamide] were synthesized successfully. These metal complexes were characterized by Fourier transform infrared, ultraviolet visible spectrometry, proton nuclear magnetic resonance spectroscopy, and mass Spectrometry, CHNS and thermogravimetric analysis. The elemental analysis confirms the structures for Mn(II), Co(II) and Ni(II) complexes similar to octahedral geometry, Cu(II) complexes as a square planar geometry and Zn(II) complexes in the tetrahedral geometry. The molar conductivities of all the metal complexes were taken in 10?3 M DMSO, and values of all the metal complexes showed their electrolytic nature which indicates the presence of chloride ions. Thermal analysis supports as the metal complexes are thermally stable. The result of antimicrobial activity against various microorganisms confirms that the metal complexes are potent bactericides and fungicides than the ligand. Metal complexes of LO with Cu(II) and Zn(II) were found to be highly active against S. typhimurium than the complexes of LM. 相似文献
Graphical abstract
96.
Adewale S. Oladipo Olusegun A. Ajayi Akeem A. Oladipo Solmaz L. Azarmi Yusuf Nurudeen Abdulazeez Y. Atta Shola S. Ogunyemi 《Comptes Rendus Chimie》2018,21(7):684-695
A magnetically recyclable eggshell-based catalyst (MKEC) was synthesized to circumvent saponification during the conversion of neem, Jatropha, and waste cooking oils (free fatty acid, 2.3–6.6%) to biodiesel. The characterization results indicated that MKEC had a mesoporous structure with the pore width of 3.24 nm, a specific surface area of 128 m2/g, and a pore volume of 0.045 cm3/g. The results confirmed that the MKEC is more tolerant to fatty acid poisoning than calcined eggshell. The effects of process parameters for maximum fatty acid methyl ester (FAME) content were evaluated by central composite design (CCD) and artificial neural network (ANN). The experimental FAME content of 94.5% was achieved for neem oil with a standard deviation (SD) of 0.68, which was in reasonable agreement with predicted values (CCD, 96.9%; ANN, 95.9%; SD, 0.73). The reusability studies showed that the mesoporous catalyst can be reused efficiently for five cycles without much deterioration in its activity. 相似文献
97.
98.
B. Mirza M. Zamani-Nasab 《理论物理通讯》2006,46(12)
In order to study the effect of large scale cosmological expansion on small systems, we assume a FriedmannRobertson-Walker type coordinate system in presence of a nonzero cosmological constant and derive a non-static Reissner-Nrdstr(o)m metric. It is an analytic function of r for all values except at r = 0, which is singular. By determining the equation of motion in this metric we can estimate how expansion of the universe may affect Pioneer‘smotion. Because the metric does not have any event horizon and so high potential regions are accessible, this may help us in better understanding AGN phenomenon. 相似文献
99.
Rajeev Kumar Mohd A. Mirza Punnoth Poonkuzhi Naseef Mohamed Saheer Kuruniyan Foziyah Zakir Geeta Aggarwal 《Molecules (Basel, Switzerland)》2022,27(5)
Oral diseases pose a major threat to public health across the globe. Diseases such as dental caries, periodontitis, gingivitis, halitosis, and oral cancer affect people of all age groups. Moreover, unhealthy diet practices and the presence of comorbidities aggravate the problem even further. Traditional practices such as the use of miswak for oral hygiene and cloves for toothache have been used for a long time. The present review exhaustively explains the potential of natural products obtained from different sources for the prevention and treatment of dental diseases. Additionally, natural medicine has shown activity in preventing bacterial biofilm resistance and can be one of the major forerunners in the treatment of oral infections. However, in spite of the enormous potential, it is a less explored area due to many setbacks, such as unfavorable physicochemical and pharmacokinetic properties. Nanotechnology has led to many advances in the dental industry, with various applications ranging from maintenance to restoration. However, can nanotechnology help in enhancing the safety and efficacy of natural products? The present review discusses these issues in detail. 相似文献
100.
Munazza Raza Mirza Matthias Rainer Shahid Duran Syed Tarique Moin M. Iqbal Choudhary Günther K. Bonn 《Biomedical chromatography : BMC》2019,33(9)
A poly(dibenzo‐18‐crown‐6) was used as a new solid‐phase extraction material for the selective enrichment of phosphopeptides. Isolation of phosphopeptides was achieved based on specific ionic interactions between poly(dibenzo‐18‐crown‐6) and the phosphate group of phosphopeptides. Thus, a method was developed and optimized, including loading, washing and elution steps, for the selective enrichment of phosphopeptides. To assess this potential, tryptic digest of three proteins (α‐ casein, β‐casein and ovalbumin) was applied on poly(dibenzo‐18‐crown‐6). The nonspecific products were removed by centrifugation and washing. The spectrometric analysis was performed using matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry. Highly selective enrichment of both mono‐ and multiphosphorylated peptides was achieved using poly(dibenzo‐18‐crown‐6) as solid‐phase extraction material with minimum interference from nonspecific compounds. Furthermore, evaluation of the efficiency of the poly(dibenzo‐18‐crown‐6) was performed by applying the digest of egg white. Finally, quantum mechanical calculations were performed to calculate the binding energies to predict the affinity between poly(dibenzo‐18‐crown‐6) and various ligands. The newly identified solid‐phase extraction material was found to be a highly efficient tool for phosphopeptide recovery from tryptic digest of proteins. 相似文献