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51.
El-Azab A. S. Ghabbour H. A. El-Husseiny W. M. Maarouf A. R. Mohamed M. A. Abdel-Aziz A. A.-M. 《Russian Journal of General Chemistry》2016,86(12):2837-2844
Russian Journal of General Chemistry - Hydrazones 2–22 were synthesized via the reaction of acetophenone with isatin derivatives and anhydrous hydrazine promoted by BF3 as a Lewis acid at... 相似文献
52.
Hairul Hisham Hamzah Nur Hidayah Saleh Bhavik Anil Patel Mohd Muzamir Mahat Saiful Arifin Shafiee Turgut Snmez 《Molecules (Basel, Switzerland)》2021,26(1)
The development of low-cost electrode devices from conductive materials has recently attracted considerable attention as a sustainable means to replace the existing commercially available electrodes. In this study, two different electrode surfaces (surfaces 1 and 2, denoted as S1 and S2) were fabricated from chocolate wrapping aluminum foils. Energy dispersive X-Ray (EDX) and field emission scanning electron microscopy (FESEM) were used to investigate the elemental composition and surface morphology of the prepared electrodes. Meanwhile, cyclic voltammetry (CV), chronoamperometry, electrochemical impedance spectroscopy (EIS), and differential pulse voltammetry (DPV) were used to assess the electrical conductivities and the electrochemical activities of the prepared electrodes. It was found that the fabricated electrode strips, particularly the S1 electrode, showed good electrochemical responses and conductivity properties in phosphate buffer (PB) solutions. Interestingly, both of the electrodes can respond to the ruthenium hexamine (Ruhex) redox species. The fundamental results presented from this study indicate that this electrode material can be an inexpensive alternative for the electrode substrate. Overall, our findings indicate that electrodes made from chocolate wrapping materials have promise as electrochemical sensors and can be utilized in various applications. 相似文献
53.
Salah E. M. Eltom Ahmed A. H. Abdellatif Hamzah Maswadeh Mohsen S. Al-Omar Atef A. Abdel-Hafez Hamdoon A. Mohammed Eiman ME. Agabein Ibrahim Alqasoomi Salem A. Alrashidi Mohammed S. M. Sajid Mugahid A. Mobark 《Molecules (Basel, Switzerland)》2021,26(12)
The ostrich oil of Struthio camelus (Ratite) found uses in folk medicine as an anti-inflammatory in eczema and contact dermatitis. The anti-inflammatory effect of a γ-lactone (5-hexyl-3H-furan-2-one) isolated from ostrich oil and its formulated nano-emulsion in formalin-induced paw edema was investigated in this study. Ostrich oil was saponified using a standard procedure; the aqueous residue was fractionated, purified, and characterized as γ-lactone (5-hexyl-3H-furan-2-one) through the interpretation of IR, NMR, and MS analyses. The γ-lactone was formulated as nano-emulsion using methylcellulose (MC) for oral solubilized form. The γ-lactone methylcellulose nanoparticles (γ-lactone-MC-NPs) were characterized for their size, shape, and encapsulation efficiency with a uniform size of 300 nm and 59.9% drug content. The γ-lactone was applied topically, while the formulated nanoparticles (NPs) were administered orally to rats. A non-steroidal anti-inflammatory drug (diclofenac gel) was used as a reference drug for topical use and ibuprofen suspension for oral administration. Edema was measured using the plethysmograph method. Both γ-lactone and γ-lactone-MC-NPs showed reduction of formalin-induced paw edema in rats and proved to be better than the reference drugs; diclofenac gel and ibuprofen emulsion. Histological examination of the skin tissue revealed increased skin thickness with subepidermal edema and mixed inflammatory cellular infiltration, which were significantly reduced by the γ-lactone compared to the positive control (p-value = 0.00013). Diuretic and toxicity studies of oral γ-lactone-MC-NPs were performed. No diuretic activity was observed. However, lethargy, drowsiness, and refusal to feeding observed may limit its oral administration. 相似文献
54.
During our screening for bioactive natural compounds from microorganisms, a novel alkaloid has been isolated from a terrestrial Streptomyces sp. isolate NR12, and named as benhamycin (1). This was along with the known metabolites, uracil, thymine, p-hydroxybenzoic acid, 2'-deoxyuridin, tryptophol, indolyl-3-carboxylic acid, and indolyl-3-carbaldehyde. Chemical structure of the novel compound was determined by detailed analysis of its spectroscopic data (extensive NMR experiments, 1 & 2D, MS spectroscopy, and MS high resolution). Structurally, Benhamycin (1) is a pentacyclic aromatic compound bearing an acridine moiety lactamized with benzene. Biological studies showed that the strain extract was moderately active against Gram-positive, Gram-negative bacteria and fungi. 相似文献
55.
S. P. Low A. Ahmad H. Hamzah M. Y. A. Rahman 《Journal of Solid State Electrochemistry》2011,15(11-12):2611-2618
A nanocomposite polymer electrolyte consisting of 49% poly(methyl methacrylate)-grafted natural rubber (MG49) as a polymer matrix, lithium tetrafluoroborate (LiBF4) as a dopant salt, and titanium dioxide (TiO2) as an inert ceramic filler was prepared by solution casting technique. The ceramic filler, TiO2, was synthesized in situ by a sol?Cgel process. The ionic conductivity was investigated by alternating current impedance spectroscopy. X-ray diffraction (XRD) was used to determine the structure of the electrolyte, and its morphology was examined by scanning electron microscopy (SEM). The highest conductivity, 1.4?×?10?5 S cm?1 was obtained at 30 wt.% of LiBF4 salt addition with 6 wt.% of TiO2 filler content. Ionic conductivity was found to increase with the increase of salt concentration. The optimum value of conductivity was found at 6 wt.% of TiO2. The XRD analysis revealed that the crystalline phase of the polymer host slightly decreased with the addition of salt and filler. The SEM analysis showed that the smoother the surface of the electrolyte, the higher its conductivity. 相似文献
56.
Second derivative spectrophotometry was applied to determine the binding constant (K) between codeine phosphate (COD) and bovine serum albumin (BSA) at simulated physiological conditions (37.00?°C and pH = 7.4). The second derivative spectra of COD in buffer solutions containing various amounts of BSA showed derivative isosbestic points. The residual background signals derived from incomplete suppression of BSA signals can be entirely eliminated in the second derivative spectra indicating that BSA has spectrophotometrically one kind of binding site for COD. The fractions of COD bound to BSA were calculated from the derivative intensity differences (??D values) of COD before and after the addition of BSA. Scatchard plot calculation suggested that the binding of COD to BSA can be explained by a partition-like non-specific binding model. The binding constant (K) was calculated from ??D values according to the non-specific binding model by a nonlinear least-squares method. K values were almost constant for all of the COD concentrations studied with good reproducibility. The fractions predicted by the K values were in good agreement with the observed values. The results indicate the usefulness of the derivative method in drug?Calbumin binding studies without the need for prior separation procedures which may disturb the equilibrium states of the samples solutions. 相似文献
57.
The effect of different antioxidants and their mixtures on the thermal aging and accelerated weathering of γ-radiation vulcanized EPDM rubber in presence of crosslinking coagent, was investigated. The compounds used were either a synergistic blend of phenolic and phosphite antioxidants, i.e. 1:4 Irganox 1076: Irgafos 168 or a blend of arylamine and quinoline type antioxidants, i.e. 1:1 IPPD:TMQ, at fixed concentration. Tinuvin 622 LD hindered amine light stabilized (HALS) was also used. The response was evaluated by the tensile strength and elongation at break for irradiated samples after thermal aging at 100°C for 28 days and accelerated weathering (Xenon test) up to 200 h. 相似文献
58.
A. Hamzah W. N. W. M. Arifin K. S. Khoo L. J. Lee S. B. Sarmani 《Journal of Radioanalytical and Nuclear Chemistry》2009,281(2):295-298
Certain bacterial strains can be employed in the removal of heavy metals from the environment. The aim of this study was to
screen potential bacteria that were tolerant towards Cu and Cd and instrumental neutron activation analysis (INAA) was used
to determine the concentrations of heavy metals in the sludge samples. The sludge samples from oil refinery plant in Malaysia
contained Cr, Cs, Cu, Eu, Fe, Hg, Mn, Sb, Sc, Th, U and Zn. Seven bacterial isolates were identified to be tolerant to 100 mg/kg
of copper and cadmium. 相似文献
59.
Hatem A. Abdel-Aziz Bakr F. Abdel-Wahab Marwa A. M. Sh. El-Sharief Mohamed M. Abdulla 《Monatshefte für Chemie / Chemical Monthly》2009,140(4):431-437
Abstract The reaction of 1-[4-(piperidin-1-yl)benzylidene]thiosemicarbazide with hydrazonoyl chlorides afforded 1,3-thiazole derivatives.
Cyclization of two compounds of the latter 1,3-thiazole by means of bromine in the presence of sodium acetate at room temperature
gave 1,3-thiazolo[2,3-c]-1,2,4-triazole derivatives. The reaction of 2-cyano-3-(4-piperidin-1-ylphenyl)prop-2-enethioamide with hydrazonoyl chlorides
under reflux in ethanol in the presence of triethylamine yielded 1,3-thiazoles. Treatment of 3-oxo-3-(piperidin-1-yl)propanenitrile
with phenyl isothiocyanate in DMF, in the presence of KOH, at ambient temperature, resulted in the formation of 3-anilino-3-mercapto-2-(piperidin-1-ylcarbonyl)acrylonitrile
which was reacted with hydrazonoyl chlorides to yield the corresponding 1,3,4-thiadiazole derivatives. Some of the newly synthesized
compounds had significant anti-arrhythmic activity.
Graphical Abstract
相似文献
60.
Elliptic flow measurements at the Brookhaven National Laboratory Relativistic Heavy Ion Collider suggest that quark-gluon fluid flows with very little viscosity compared to weak-coupling expectations, challenging theorists to explain why this fluid is so nearly "perfect." It is therefore vital to find quantitative experimental information on the viscosity of the fluid. We propose that measurements of transverse momentum fluctuations can be used to determine the shear viscosity. We use current data to estimate the viscosity-to-entropy ratio in the range from 0.08 to 0.3 and discuss how future measurements can reduce this uncertainty. 相似文献