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111.
Ahmed Jasim M. Al-Karawi Ali Jasim Hammood Adil A. Awad Al-Ameen Bariz OmarAli Saba Riad Khudhaier Dhafir T. A. Al- Heetimi 《Liquid crystals》2018,45(11):1603-1619
The following organic and organic–inorganic hybrid compounds were prepared as photo-luminescent materials following efficient and practical synthetic methods: 1,3-bis[4-(n-alkoxy)phenyl]-2-propen-1-one (where, n-alkoxy: O(CH2)nH, n = 6,7,8,9 or 10); 3,5-bis[4-(n-alkoxy)phenyl]-1H-pyrazole (where, n-alkoxy: O(CH2)nH, n = 6,7,8,9 or 10) (in case of n = 7, a mixture of 3,5-bis(4-heptyloxyphenyl)-1H-pyrazole and 3,5-bis(4-heptyloxyphenyl)-4H-pyrazole was detected) and bis(3,5-bis [4-(n-alkoxy) phenyl]-1H-pyrazole) silver(I) nitrate (where, n-alkoxy: O(CH2)nH, n = 6,7,8,9 or 10). The prepared compounds have been characterised and their structures were elucidated depending upon (FTIR, UV-Vis, 1HNMR, 13CNMR, 2D 1H-1H-COSY, 2D 1H-13C-HSQC and mass spectra) in addition to molar conductivity measurements for silver(I) complexes. The mesomorphism behaviour of the prepared compounds was studied using polarised light optical microscopy and confirmed with differential scanning calorimetry and X-ray powder diffraction techniques. The studies showed that among all of these compounds only the pyrazole derivatives are liquid crystal materials. The luminescent properties of all the prepared compounds were also investigated which confirmed that all of these compounds are photo-luminescent in the crystalline solid state and in the mesophase. 相似文献
112.
Guo Xue Feng Yurun Ma Li Yu Jincheng Jing Jie Gao Dezhi Khan Adil Saleem Gong Hongyu Zhang Yujun 《Journal of Radioanalytical and Nuclear Chemistry》2018,317(1):397-407
Nickel hydroxide solubility has been studied in this work in different cementitious systems. Our results indicate that once Glenium® 27, cement superplasticizer admixture, is added to water and then mixed with cement, this polymeric material is stabilized and not released back to the aqueous solution, with negligible effects on the mobility of nickel. Contrary to that, when Glenium® 27 is added directly in solution at high dosages, an important effect is observed on nickel behaviour. Thermodynamic calculations indicate that the effect of such component on Ni is likely the effect that other small organics could have over this element.
相似文献113.
Porphyrin-metal complexes are potentially useful to catalyze redox reactions, which convert toxic and biologically recalcitrant
compounds to compounds that are less toxic and more amenable to biotreatment. Porphyrins, in the absence of proteins as in
ligninases, peroxidases, and oxidases, are potentially more robust than enzymes and microbial cultures in the treatment of
inhibitory substances.
2,4,6-Trichlorophenol was used as a model compound for chlorinated phenols and as a substrate for various porphyrin-metal
complexes acting as oxidation catalysts. t-Butyl hydroperoxide was the oxidizing agent. TCP was shown to be at least partially
dechlorinated and the aromatic ring broken in reaction products. All porphyrins exhibited saturation kinetics with regard
to the initial TCP concentration in reaction mixtures. Electron-withdrawing substituents on the porphyrins were observed to
increase stability of the catalysts to inactivating ring-centered oxidation. 相似文献
114.
115.
Akbar Ali Mukhtar Ahmad Majid Niaz Akhtar Saleem Farooq Shaukat Ghulam Mustafa M. Atif W. A. Farooq 《Russian Journal of Applied Chemistry》2016,89(4):517-534
Nanobiotechnology has opened a new and exciting opportunities for exploring urea biosensor based on magnetic nanoparticles (NPs) mainly Fe3O4 and Co3O4. These NPs have been extensively exploited to develop biosensors with stability, selectivity, reproducibility and fast response time. This review gives an overview of the development of urea biosensor based on Fe3O4 and Co3O4 for in vitro diagnostic applications along with significant improvements over the last few decades. Additionally, effort has been made to elaborate properties of magnetic nanoparticles (MNPs) in biosensing aspects. It also gives details of recent developments in hybrid nanobiocomposite based urea biosensor. 相似文献
116.
Shaikh S Muneera MS Thusleem OA Tahir M Kondaguli AV Ruckmani K 《Journal of chromatographic science》2007,45(6):311-314
A new specific, accurate, precise, and reproducible selective online dissolution method for rosiglitazone maleate is developed and validated for the dissolution of rosiglitazone maleate in pharmaceutical formulations. The rationale of the method is based on the direct measurement of the absorbance of the analyte in the buffer medium at 242 nm using buffer as blank. Dissolution is achieved on a dissolution test apparatus consisting of photo diode array spectrophotometer, peristaltic pump, and temperature controller, using 0.01N HCl and 0.05M potassium chloride as the dissolution medium. The proposed method is developed, optimized, and validated in terms of linearity, reproducibility, accuracy, and selectivity for the dissolution of rosiglitazone maleate in pharmaceutical formulations. The method is found to be linear in the range of 1 to 14 microg/mL of rosiglitazone maleate with a correlation coefficient of 0.999. The dissolution studies of rosiglitazone maleate tablets obtained by the proposed method are in good agreement with those by high-performance liquid chromatography. 相似文献
117.
1,3,4-Oxadiazole, 1,3,4-thiadiazole and 1,2,4-triazole derivatives as potential antibacterial agents
Since the introduction of the first antibiotic (penicillin, 1942) into medical practice, to date, there has been an ongoing “race” between scientists creating new drugs and pathogenic bacteria. Antibiotic-bacteria are becoming progressively common, and to make matters worse, more and more bacteria are becoming resistant to all known antibiotics. The traditional method for this problem is to introduce new antibiotics that kill the resistant mutants. This specific “arms race” resulted into thousands of potentially active chemicals are synthesized in laboratories around the world every day.1,3,4-Oxadiazole; 1,3,4-thiadiazole; 1,2,4-triazole and some of their derivatives are involved in modifications at the following axes: First, attaching a thio-group into heterocyclic rings. Second, introducing different substitutions at position 5 which often are the residuals of the synthetic starting materials such as simple aliphatic, substituted aliphatic chains, aromatic carbocyclic and heterocyclic residues. 相似文献
118.
Ayta Gültekin Arzu Ersz Deniz Hür Nalan Ylmaz Sarzlü Adil Denizli Rdvan Say 《Applied Surface Science》2009,256(1):142-148
Taking into account the recognition element for sensors linked to molecular imprinted polymers (MIPs), a proliferation of interest has been witnessed by those who are interested in this subject. Indeed, MIP nanoparticles are theme which recently has come to light in the literature. In this study, we have proposed a novel thiol ligand-capping method with polymerizable methacryloylamidocysteine (MAC) attached to gold nanoparticles, reminiscent of a self-assembled monolayer. Furthermore, a surface shell by synthetic host polymers based on molecular imprinting method for recognition has been reconstructed. In this method, methacryloyl iminodiacetic acid-chrome (MAIDA–Cr(III)) has been used as a new metal-chelating monomer via metal coordination–chelation interactions and dipicolinic acid (DPA) which is the main participant of Bacillus cereus spores has been used as a template. Nanoshell sensors with templates produce a cavity that is selective for DPA. The DPA can simultaneously chelate to Cr(III) metal ion and fit into the shape-selective cavity. Thus, the interaction between Cr(III) ion and free coordination spheres has an effect on the binding ability of the gold nanoparticles nanosensor. The interactions between DPA and MIP particles were studied observing fluorescence measurements. DPA addition caused significant decreases in fluorescence intensity because they induced photoluminescence emission from Au nanoparticles through the specific binding to the recognition sites of the crosslinked nanoshell polymer matrix. The binding affinity of the DPA imprinted nanoparticles has been explored by using the Langmuir and Scatchard methods and the analysis of the quenching results has been performed in terms of the Stern–Volmer equation. 相似文献
119.
Thirteen phases are now evidenced in the composition space diagram of the Al(OH)3–tren–HF–ethanol system at 190 °C. Solvothermal syntheses are performed under microwave heating. Six new organic–inorganic fluorides crystallise and their structures are determined: (H3O)·[H4tren]2·(AlF6)3·6H2O (P-1, Z = 2), [H3tren]2·(AlF5(H2O))3·8H2O (C2/c, Z = 8), [H3tren]4·(AlF6)2·(Al2F11)·(F)·10H2O (P21/n, Z = 2), [H3tren]2·(Al4F18)·3.5H2O (P63, Z = 2), [H3tren]2·(Al4F18) (P-1, Z = 1), and [H3tren]4·(Al8F35)·(OH)·H2O (P-1, Z = 1). The existence domains are approximately located for all phases. Tren amine is tetraprotonated at high HF concentration, otherwise it is triprotonated. A protonated water cluster, H3O+(H2O)6, appears in (H3O)·[H4tren]2·(AlF6)3·6H2O while a new Al4F18 unit, found in [H3tren]2·(Al4F18), is evidenced; it results from corner and edge sharing association of four AlF6 octahedra. Finally, the structure of [H3tren]4·(Al8F35)·(OH)·H2O revealed the largest known fluoroaluminate polyanion, built from eight vertex sharing AlF6 octahedra, (Al8F35)11−. 相似文献
120.
This paper describes the peristaltic motion of a non-Newtonian fluid in a channel having compliant boundaries. Constitutive equations for a Maxwell fluid have been used. Perturbation method has been used for the analytic solution. The influence of pertinent parameters is analyzed. Comparison of the present analysis of Maxwell fluid is made with the existing results of viscous fluid. 相似文献