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161.
The development of an optical pH sensor for high pH values is described based on the immobilization of Aniline Blue on an optically transparent triacetylcellulose membrane. The membrane is useful for repetitive and reversible pH measurements in the pH range of 8.8-13. The relative standard deviation is about 1.6% and 2% for seven measurements of the maximum change at 579 nm from pH 9 to 10.8 and from pH 11.1 to 12.8, respectively. Other advantages of the sensor include rapid equilibration time, long term stability, reversibility, high sensitivity, freedom from interference of other cations and ease of fabrication.  相似文献   
162.
In the present study, for the first time, we successfully employed zeolite/Fe3O4 as a new magnetic nanoparticle sorbent in magnetic solid‐phase extraction for determining phthalates in aqueous samples. Gas chromatography with flame ionization detection was used to detect the target analytes as a powerful instrumental analysis. Affecting parameters in the extraction process, including the amount of adsorbent, adsorption and desorption time, and volume of desorption solvent, were optimized using a response surface methodology based on central composite design. Under the optimum conditions, the linear range for dibutyl phthalate and bis(2‐ethylhexyl phthalate) was varied in the interval of 10–1700 and 10–1200 μg/L, respectively. Limits of detection were 2.80 μg/L for dibutyl phthalate and 3.20 μg/L for bis(2‐ethylhexyl phthalate). The recovery value for the extraction of target analytes was between 97 and 111%. The repeatability and reproducibility of the new proposed method were obtained: 10–13% and 13–13.5%, respectively. The increased sensitivity in using the proposed method has been demonstrated. Compared with previous methods, the new proposed method is an accurate, rapid, and reliable sample‐pretreatment method.  相似文献   
163.
Journal of Analytical Chemistry - In this research, chemiluminescence (CL) of several aldehydes (such as oxalaldehyde, N-isovaleryl-3-amino-propanal as the bioluminescent earthworm luciferin,...  相似文献   
164.
Structural Chemistry - The interaction of procarbazine (PC) anticancer drug with fullerene-like nanocages (B24N24, AlB23N24, SiB23N24, B24N23Si, CB23N24) was studied by density functional theory...  相似文献   
165.
Russian Journal of Organic Chemistry - A series of novel sulfonamides containing a 2-amino-1,3-thiazole fragment have been synthesized using a simple and efficient method under solvent-free...  相似文献   
166.
In the present work, we developed an effective protocol for the synthesis of β‐amino carbonyl compounds and synthesis of benzylamino coumarin derivatives through Mannich type reaction in high yields. Fe3O4@ZrO2/SO42‐ was employed as an effective heterogeneous nanocatalyst for the Mannich reaction. This research consists of two sections. In first section, β‐amino carbonyl derivatives were synthesized under solvent‐free condition. In the other section, benzylamino coumarin compounds were synthesized at room temperature. The present approach offers several advantages such as short reaction times, low cost, easy work‐up, mild reaction conditions, high yields and ease of recovery and reusability of the catalyst without significant loss of activity.  相似文献   
167.
The aim of this study was to develop methoxy poly(ethylene oxide)‐b‐poly(ε‐caprolactone) (MePEO‐b‐PCL) containing stearyl (St) substituents on PCL, and assess the efficacy of nanocarriers formed from this structure in comparison to unmodified MePEO‐b‐PCL and those with carboxyl substitutes on PCL on the solubilization and delivery of Amphotericin B (AmB). Prepared block copolymers were characterized for their molecular weight by 1H NMR and gel permeation chromatography. The self‐assembly of synthesized MePEO‐b‐PStCL to spherical particles of nanometer size range was shown by dynamic light scattering as well as electron and atomic force microscopy. Encapsulated AmB showed a reduction in its hemolytic activity against rat red blood cells in comparison to the commercial formulation of AmB, Fungizone.

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168.
In this paper we define the hyper operations ?, ∨ and ∧ on a hyper MV ‐algebra and we obtain some related results. After that by considering the notions ofhyper MV ‐ideals and weak hyper MV ‐ideals, we prove some theorems. Then we determine relationships between (weak) hyper MV ‐ideals in a hyper MV ‐algebra (M, ⊕, *, 0) and (weak) hyper K ‐ideals in a hyper K ‐algebra (M, °, 0). Finally we give a characterization of hyper MV ‐algebras of order 3 or 4 based on the (weak) hyper MV ‐ideals (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
169.
Nanoparticles of palladium were supported on SiO2 by chemical vapor deposition technique. The obtained Pd nanocatalyst was characterized by various techniques. This catalyst was found to be very efficient for the selective cross‐coupling of hydroxyl‐substituted aryl iodides and bromide with arylboronic acids in water at room temperature to produce the corresponding hydroxyl‐substituted biaryls. Coupling of phenylboronic acid with aryl iodides and bromides carrying substituents other than hydroxy group was also performed efficiently in refluxing ethanol. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
170.
1,2,3-Triazole-3-oxoisoindoline-1-carboxamide system was successfully synthesized by using a combination of Ugi and click reactions. This two-step, one-pot synthesis was started by the reaction of 2-formyl benzoic acid, propargyl amine, and cyclohexyl isocyanide in ethanol. The resultant Ugi adduct underwent a copper-catalyzed click reaction, producing the desired products in good yields.  相似文献   
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