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1.
Chemistry related to three catalytic carbonylation reactions is discussed. Synthesis of diphenylurea from nitrobenzene, aniline,
and CO gives isolated yields above 98% at 100–120 °C and 15–60 bar of CO in the presence of a palladium (II) complex, PPh3 and NEt4Cl. Experimental evidence was provided to prove a new reaction stoichiometry and involvement of a carbamoyl intermediate.
In carbonylation of HCHO over ion exchange resin catalysts, reaction temperature, time, pressure, and solvent were important
variables to obtain high yields of methyl glycolate. Carbonylation of isobutylphenylethanol at 120°C and 40 bar of CO in the
presence of PdCl2−PPh3−HCl gives 98% yield of α-(4-isobutylphenyl) propionic acid (ibuprofen). Each catalyst component had a definite role that
is indispensable for an efficient overall reaction. 相似文献
2.
3.
4.
A new (E,E)-dioxime, (6Z,7Z)-15,16-dihydro-14H-dibenzo[b,h][1,10,4, 7]dithiadiazacyclotride-cine-6,7(5H,8H)-dionedioxime (H
2
L) has been synthesized by reacting cyanogen-di-N-oxide (2) with 2,2′-[propane-1,3-diylbis(thio)]dianiline (1). Mononuclear complexes (4) and (5) of this ligand have been synthesized by reacting the vic-dioxime (H2L) with NiCl2 · 6H2O and CoCl2 · 6H2O, respectively. The BF
2
+
capped Ni(II) and Co(III) complexes (6) and (7) of the dioxime have been synthesized from (4) and (5). The new compounds were characterized by a combination of elemental analysis, 1H- and 13C-n.m.r, i.r. and m.s. spectral data. 相似文献
5.
P. Arikan O. Acar R. Acar G. A. Aycik M. A. Cetiner H. Demirel N. Efe T. Golge R. Gurellier R. Kirmaz S. Tulumen H. Yucel A. Zararsiz Y. Agus 《Journal of Radioanalytical and Nuclear Chemistry》2004,259(3):391-394
Comprehensive Quality Control (QC) and Quality Assurance (QA) Program is stated on the quality policy, organization, methods
and records for nuclear analytical laboratories which are necessary for improvement of productivity, to upgrade the performance,
credibility and reputation. The proper and complete identification of quality elements for management and technical requirements
are being written in Quality Manual as well as analytical and organizational procedures and working instructions according
to ISO 17025 standard. Technical ability of gamma, X-ray and a/b laboratories in the Center has been checked by participation
in proficiency test, critical technical variables, and quality results. Performance of quality system has been controlled
by external audit inspection, progress reports and service to clients. The present study is a framework of the model project
of IAEA, coded RER/2/004, which has resulted self-sustainable accreditation from the national body, TURKAK.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
6.
Melek Gul Dincmen Peter J. Hauser Nevin Cigdem Gursoy 《Plasma Chemistry and Plasma Processing》2016,36(5):1377-1391
In this study, three hydrophilic monomers; 2-acrylamido-2-methyl-1-propanesulfonic acid, 2-hydroxyethyl methacrylate, diallyldimethylammonium chloride (DADMAC) were selected and their performance as an antistatic finish on nylon 6,6 fabrics was investigated. A non-thermal, high density atmospheric pressure plasma was used to graft polymerize the monomers on nylon 6,6 fabrics. Fabrics were first treated with solutions of monomer in water, air dried and then treated with helium plasma to graft polymerize the monomer on the fiber surface. Surface resistivity values were measured before and after soxhlet extraction with water. Results showed that the DADMAC monomer provided better antistatic properties to fabrics. Further studies with DADMAC monomer were made; effects of plasma post exposure time, plasma pre-exposure time, plasma power, concentration of the monomer and existence of a crosslinker were investigated. Higher plasma power, higher concentration of the monomer and longer post exposure times all gave better antistatic properties to the nylon 6,6 fabrics. Acid dye staining, UV–Vis and FT-IR measurements were conducted and results confirmed a grafted poly-DADMAC layer on the fabric surface. 相似文献
7.
8.
Mustafa Versan Kök Kiymet Gizem Gul 《Journal of Thermal Analysis and Calorimetry》2013,114(1):269-275
In this study, two Turkish crude oils from southeastern part of Turkey and their saturate, aromatic, resin fractions were analyzed by differential scanning calorimetry (DSC). The experiments were performed at three different heating rates (5, 10, 15 °C min?1) under air atmosphere. Two different reaction regions were observed from DSC curves due to the oxidative degradation of crude oil components. In the first reaction region, it was deduced that the free moisture, volatile hydrocarbons were evaporated from the crude oils, light hydrocarbons were burned, and fuel was formed. The second reaction region was the main combustion region where the fuel was burned. From DSC curves, it was observed that as the sample got heavier, the heat of the reaction increased. Saturates gave minimum heat of reaction. As the heating rate increased, shift of peak temperatures to high values and extended reaction region intervals were observed. The kinetic analysis of the crude oils and their fractions were also performed using ASTM E-698 and Borchardt and Daniels methods, respectively. Activation energy values of the crude oil samples and the fractions’ high-temperature oxidation region were close to each other and varied between 67 and 133 kJ mol?1 in ASTM and 35 and 154 kJ mol?1 in Borchardt and Daniels methods, respectively. 相似文献
9.
Gamze Karayel Incili Gul Asiye Aycık 《Journal of Radioanalytical and Nuclear Chemistry》2014,301(2):417-426
Schiff base hydrazone derivative (HL) sorbent was synthesized according to the literature to be used in the adsorption and preconcentration of U(VI) ions from aqueous solution and it was exposed to immobilization, and new solid support material was obtained. For this purpose, Schiff base hydrazone derivative (HL) was chemically bonded to silica gel surface immobilized 3-aminopropyl trimethoxysilane, then analyzed by Fourier transform infrared, Brunauer–Emmett–Teller, scanning electron microscopy and elemental analysis. The influence of the solution pH, amount of sorbent, contact time, temperature, foreign ion effect and initial U(VI) concentration was investigated. The maximum U(VI) uptake capacity was found to be 8.46 mg/g. 相似文献
10.
Preparation of antibody-coated gold nanoparticles (GNPs) specific to aflatoxins B1, B2, G1 and G2 and its use in developing aflatoxins diagnostic method were presented in this paper. The formation of gold-labeled antibodies was accomplished at optimal condition. Due to severe overlapping between the emission profiles for the aflatoxins, they cannot be determined by direct inspection of data. The strategy used in this study, constituted by artificial neural network (ANN), was easy to implement and to originate reliable results. ANN can be successfully applied to spectrofluorimetric spectra matrices to simultaneous determination of total aflatoxins. Quantitative results obtained using ANN method for aflatoxins in pistachio nuts samples were compared to those obtained using the HPLC method. Obtained results using these two methods did not show significant differences. 相似文献