Có 240+ tài liệu thuộc chủ đề "Journal of Chemistry"
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According to the spectral data of the new metal complexes obtained, both metal complexes are in the monoclinic crystal system and in the P2 1 /c and P2 1 space groups, respectively.. The asymmetric unit of the metal complex [CoK 4 (µ 10 -C 6 H 5 O 7 ) 2 ] n contains one Co(II) ion, two potassium cations,...
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Organotemplate-free Cs-ABW nanozeolite as highly reactive and recyclable catalyst for Henry reaction between benzaldehyde and nitroethane. Abstract: Zeolite Cs-ABW nanocatalyst has been hydrothermally synthesized without using any harmful organic template. The orthorhombic Cs-ABW nanocrystals (mean size of 32 nm) have high aluminum content (Si/Al ratio = 1.14) and possess high basicity.. The nanocrystals also exhibit better catalytic activity than conventional...
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Abstract: The aim of this work was to prepare metal soaps of epoxidized sunflower oil (ESO) and use them as thermal stabilizers for polyvinyl chloride (PVC). The prepared metal soaps derivatives of ESO were used as thermal stabilizers for plasticized PVC. °C, and rheological properties of PVC samples were tested. The best thermal stabilization effects were observed in the presence...
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Abstract: The simplest ideas of antiaromaticity refer to regular monocyclic systems and the eigenfunctions of the Hückel Hamiltonian for 4n π electrons in such systems. The antiaromaticity is expressed in the energy penalty for such idealized systems relative to the Hückel energy for 2n noninteracting π pairs. Observed systems seldom achieve the regular planar geometry assumed in this picture, owing...
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S)-2-(2-Methoxyphenyl)-1-phenylethanol (1a) (1.0 g, 4.4 mmol), PPh 3 (4.60 g, 17.6 mmol), and phthalimide (1.94 g, 13.2 mmol) were put into a Schlenk flask (250 mL). Then diisopropyl azodicarboxylate (DIAD) (3.50 mL, 3.56 g, 17.6 mmol) was dropwise transferred into the tube with the aid of a syringe, under cooling with an ice bath. δ m, 2H m, 4H m,...
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An exploration of new avenues regarding deep tissue penetration and higher singlet oxygen efficiencies: novel near-IR photosensitizers for photodynamic. Abstract: A series of novel BODIPY-bearing electron-withdrawing groups at the meso position are reported here.. According to the optical measurements, it may be clearly seen that the introduction of electron-donating groups into 3,5-positions and the presence of electron-withdrawing groups at the...
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Inversely, the crystallinity of the washed samples was lower. Contrary to expectations, the decrease in the tensile strength and elongation at break was delayed as a result of the washing, despite a higher oxidation rate.. One of the most popular applications of polyethylene is in the agricultural field as films for greenhouse coverings. The interaction with surrounding oxygen causes an...
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Intermolecular complexes of halocyclopropenone derivatives with the hypohalous acids HOF, HOCl, HOBr, and HOI. Abstract: The intermolecular interactions between halocyclopropenone derivatives (HC 3 OX. Y = I, Br, Cl, and F) were studied via the MP2 method utilizing the aug-cc-pVTZ and aug-cc-pVTZ(-PP) basis sets. The results obtained indicated that interactions in the Type 1 complexes were stronger than those in...
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The physicochemical and porous properties and the surface chemistry of the sorbents were investigated and compared in detail. It was found that acid-washing treatment helped to reduce the ash content of GAC and cleaned its internal space. Activated carbons (ACs) generally consist of heteroatoms such as oxygen, nitrogen, and sulfur, which create surface functionalities if placed on the graphene plates’...
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and the third step involved refluxing with ethyl bromopyruvate in ethanol to afford a thiazole ring. Step 1: DCC (16.21 g, 0.079 mol) was added to a solution of 1-(tert-butoxycarbonyl)piperidine-4-carboxylic acid (12.03 g, 0.052 mol) in dichloromethane (DCM) (200 mL). for 3 h, triethylamine (TEA) (21 mL) and ammonium chloride (NH 4 Cl) (4.16 g, 0.079 mol) were then added,...
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Modification of biomass-derived activated carbon with magnetic α -Fe 2 O 3 nanoparticles for CO 2 and CH 4 adsorption. Abstract: Magnetic and nonmagnetic activated carbons (ACs) were successfully prepared by using AC obtained from spent coffee grounds (SCGs) for use in CO 2 and CH 4 capture. SCGs were activated by chemical activation to produce ACs and a magnetic...
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A microwave-assisted highly stereoselective one-pot Wittig reaction under solvent-free conditions. Abstract: We report a novel microwave-assisted two-step, one-pot protocol for the synthesis of olefins (alkenes) via Wittig reaction. The reaction was carried out under solvent-free conditions using basic alumina both as a heterogeneous catalyst and a solid support. In addition, owing to the solid-state nature of the reactions, our procedure...
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A well-known and interesting carbon ( 13 C) and fluorine ( 19 F) interaction in 13 C NMR spectra during fluorination of hydroxy derivatives (H1–H8) to their consecutive fluoro derivatives (F1–F8) could be seen clearly. The 13 C NMR pulse sequence without C-F decoupling shows C-F splitting in the carbon spectrum. The –CH-OH carbon peak of H1 at δ 68.46...
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Because of the different conjugation patterns, their solid state nuclear magnetic resonance, infrared, and ultraviolet/visible light absorption analyses indicated significant differences. Besides the discussions on the porous properties of the obtained polymeric networks, the presented spectroscopic investigations can be useful for identifying the structure-property relationship of the novel conjugated porous polymeric structures, since the characterization of such nonsoluble compounds by...
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Effect of Fe substitution on the partial oxidation of methane to syngas over La 0.7 Sr 0.3 Co 1 − y Fe y O 3 − δ perovskites. Abstract: In this research, a series of La 0.7 Sr 0.3 Co 1 − y Fe y O 3 − δ ( y was successfully synthesized by a solid- state reaction method...
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doi:10.3906/kim-1808-51 h t t p. Improving the mechanical and thermal properties of chlorinated poly(vinyl chloride) by incorporating modified CaCO 3 nanoparticles as a filler. Abstract: Chlorinated poly(vinyl chloride) (CPVC)/calcium carbonate nanocomposites were successfully prepared by the incorporation of calcium carbonate (CaCO 3 ) nanoparticles into the CPVC matrix. The compatibility between the two phases was obtained by surface modification of...
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Improvement of the mechanical and thermal properties of polyester nonwoven fabrics by PTFE coating. Abstract: Polyester (polyethylene terephthalate) is one of the most widely used polymers in textiles. On the other hand, polyester nonwovens are used in many products as wipes, filters, and padding. The surface properties of polyester nonwovens are often not perfect for a specific application and need...
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The viscosity of the PILs (PIL was measured using a cone-and-plate viscometer at ambient temperature. Quantum chemical calculations were used to explain the cation/anion ratio in the PILs. Reaction energies in the gas phase calculated at M062X/6-311 +G(d,p) level were used to determine the cation/anion ratio. The wear protection of PILs and 15W40 engine oil was determined by considering the...
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Fixed-bed column experiments were performed under various operational conditions to evaluate the performance of the adsorbent bed breakthrough curve. Comparison of the kinetic models indicated that the DES adsorption process was well described by the intraparticle diffusion model for NC, pseudo-second-order and fractional power kinetic models for NC-Brij, and pseudo-second-order model for NC-saponin.. Endocrine-disruptive compounds (EDCs) like DES have adverse...
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Sustainable process for the production of symmetrical dibasic acid ester-based thermal energy storage materials from lipids. Abstract: Oleochemical-based long-chain diesters are potential organic phase change materials convenient for thermal energy storage. The development of efficient and green methods is an important requirement for the preparation of these environmentally friendly compounds, which also are finding wide industrial application. Thus, in the...