The selective aerobic oxidation of methylaromatics to benzaldehydes using a unique combination of two heterogeneous catalysts

A unique combination of a supported cobalt complex and the first example of supported NHPI in acetic acid gives a surprisingly stable heterogeneous catalytic system for the selective aerobic oxidation of methylaromatics to benzaldehydes at atmospheric pressure.     

Sensitive Kinetic-Spectrophotometric Determination of Trace Amounts of Periodate Ion

A simple, precise, sensitive and accurate method was developed for rapid determination of trace quantities of periodate. The method is based on the accelerating effect of periodate on the reaction of bromate and hydrochloric acid in the presence of hydrazine. The decolorization of methyl orange with the reaction products was used to monitor the reaction spectrophotometrically at 525 nm. Periodate could be determined in the concentration ranges of 0.02–1.5 g/mL. The relative standard deviation for ten replicate determinations of 0.3 g/mL of periodate was 1.12%. The method was applied to the determination of periodate in water samples and indirect determination of ethylene glycol in gasoline and glycerol in vegetable oil via Malaprade reaction with satisfactory results.     

Pseudo-poly(amino acid)s: study on construction and characterization of novel chiral and thermally stable nanostructured poly(ester-imide)s containing different trimellitylimido-amino acid-based diacids and pyromellitoyl-tyrosine-based diol

A new class of chiral and potentially biodegradable poly(ester-imide)s (PEI)s as pseudo-poly(amino acid)s (PAA)s bearing natural amino acids in the main chain was synthesized. In this investigation, N,N′-(pyromellitoyl)-bis-(L-tyrosine dimethyl ester) as a biodegradable optically active diphenol and synthesized trimellitic anhydride-derived dicarboxylic acids containing different natural amino acids such as S-valine, L-methionine, L-leucine, L-isoleucine, and L-phenylalanine were used for direct polyesterification. With the aim of tosyl chloride/pyridine/N,N′-dimethylformamide system as a condensing agent, the new optically active PEIs were obtained in good yields and moderate inherent viscosity up to 0.42 dL/g. The obtained polymers were characterized with FT-IR, ¹H-NMR, X-ray diffraction (XRD), field emission scanning electron microscopy, elemental, and thermogravimetric analysis techniques. These polymers show high solubility in organic solvents, such as N,N′-dimethyl acetamide, N-methyl-2-pyrrolidone, and sulfuric acid at room temperature, and are insoluble in solvents, such as methylene chloride, cyclohexane, and water. Morphology probes showed these pseudo-poly(amino acid)s were noncrystalline and nanostructured polymers. On the basis of thermogravimetric analysis data, such PAAs are thermally stable and can be classified as self-extinguishing polymers. In addition due to the existence of amino acids in the polymer backbones these pseudo-PAAs not only are optically active but also are expected to be biodegradable and therefore could be classified under eco-friendly polymers.     

Production and evaluation of a 67Ga-labeled anti-Ror1 monoclonal antibody in a mouse model of breast cancer

Journal of Radioanalytical and Nuclear Chemistry - Receptor tyrosine kinase Ror1 is widely expressed during embryogenesis but it is absent within most mature tissues. However, expression of Ror1...     

Supported Preyssler Nanoparticles in Synthesis of 1,3‐Diaryl‐5‐Spirohexahydropyrimidines

Silica‐supported Preyssler nanoparticles (H₁₄[NaP₅W₃₀O₁₁₀])/SiO₂ are used as a new and recyclable catalyst for the preparation of 1,3‐diaryl‐5‐spirohexahydropyrimidines via a one‐pot condensation of anilines, formaldehyde, and cyclohexanone.     

Application of H-point standard addition method and partial least squares to the simultaneous kinetic-potentiometric determination of hydrazine and phenylhydrazine

Simultaneous determination of hydrazine (HZ) and phenylhydrazine (PHZ) by H-point standard addition method (HPSAM) and partial least squares (PLS) regression was carried out based on kinetic data from novel potentiometry methods. The rate of chloride ion production in the reaction of HZ and PHZ with N-chlorosuccinimide (NCS) was monitored by a chloride ion-selective electrode. The experimental data show the good ability of ion-selective electrodes (ISEs) as detectors not only for the direct determination of chloride ion but also for simultaneous kinetic-potentiometric analysis using HPSAM and PLS methods. The methods are based on the differences observed in the production rate of chloride ions. The results show that simultaneous determination of HZ and PHZ can be performed in concentration ranges of 0.5 - 20.0 and 0.8 - 25.0 microg mL(-1), respectively. The total relative standard error for applying the PLS method to 8 synthetic samples in the concentration ranges of 1.0 - 16.0 microg mL(-1) for HZ and 2.0 - 16.0 microg mL(-1) for PHZ was 3.96. In order for the selectivity of the method to be assessed, we evaluated the effects of certain foreign ions upon the reaction rate and assessed the selectivity of the method. Both methods (PLS and HPSAM) were evaluated using a set of synthetic sample mixtures and then applied for simultaneous determination of HZ and PHZ in water samples.     

Stereoselective Hydrolysis of Substituted Cyclopropanedicarboxylates with Pig Liver Esterase

The hydrolysis of the meso-cyclopropane-1,2-dicarboxylates 1a - 3a , 4 , 5a , 6a , and 9 , containing various substituents at C(3), and of the rac-3-phenylcyclopropane-1,2-dicarboxylates 7a , 8a , and 10 with pig liver esterase (PLE) is described. The stereoselectivtty and absolute configurations of the products were determined. An interpretation of results was attempted on the basis of a recent active-site model for PLE.     

Iron Oxychloride/Bovine Serum Albumin Nanosheets as Chemodynamic Therapy Agents

Iron oxychloride (FeOCl) is known for reactive oxygen species (ROS) generation through Fenton chemistry. The activity of FeOCl is preserved in the slightly acidic pH value of the tumor microenvironment (pH 6.5−6.9). Such property can be advantageous in biobased systems, where ROS generation can be modulated in slightly acidic conditions, which is characteristic of the solid tumor microenvironment. In the present study, BSA-stabilized FeOCl nanosheets (NSs) are synthesized and characterized by transmission electron microscope, Fourier transform infrared spectroscopy, zeta potential analysis, dynamic light scattering, and UV–vis spectroscopy. The morphology of the nanoparticles is flake-like, and their hydrodynamic diameter is around 200 nm. MTT, apoptosis assay, and trypan blue staining evaluate the toxicity of FeOCl NSs toward the 4T1 cell line. It is found that the toxicity of the NSs is higher in physiological conditions of solid tumors (pH 6.5, H₂O₂ 100 × 10⁻⁶ m ) than in the conditions of healthy organs (pH 7.4). Specifically, cancer cells are in their late apoptotic stage by more than eight times higher at pH 6.5 than pH 7.4. The toxicity results are in agreement with the in vitro catalytic assay of the NSs. Therefore, the FeOCl NSs can be the building blocks for constructing chemodynamic therapy agents.     

Study of Coulomb collisional effects on the propagation of electromagnetic waves in a turbulent plasma

The presence of Weibel instability in laser-irradiated fuel could be detrimental to the process of ablative implosion, which is necessary for achieving thermonuclear fusion reactions. In this paper, the effect of the Coulomb collisional within the turbulent plasma on the Weibel instability growth rate has been investigated for linear and circular polarization. The results indicate that the Weibel instability growth rate at circular polarization near the ignition centre of the fuel fusion (collisional plasma) is about 10⁵ times higher than the collisional Weibel instability growth rate at linear polarization. The Weibel instability growth rate is observed near the critical density of the fuel fusion (collisionless plasma) at linear polarization and enhancement near the foot of the heat in front of the fuel fusion. By increasing the steps of the density gradient plasma in the low-density corona, electromagnetic instability occurs at a higher stress flow. Therefore, the deposition condition of electron beam energy in circular polarization of turbulent plasma can be shifted to the fuel core for suitable ignition.