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161.
162.
J. Sarah Caygill Stuart D. Collyer Joanne L. Holmes Frank Davis Séamus P. J. Higson 《Electroanalysis》2013,25(11):2445-2452
We describe the use of cobalt phthalocyanine as a mediator to improve the sensitivity for the electrochemical detection of TNT. Commercial screen‐printed electrodes containing cobalt phthalocyanine were employed for determination of TNT. Improved sensitivities compared to screen‐printed carbon electrodes without phthalocyanine were observed, current response for cyclic voltammetric measurements at modified electrodes being at least double that of unmodified electrodes. A synergistic effect between oxygen and TNT reduction was also observed. Correlation between TNT concentrations and sensor output was observed between 0–200 µM TNT. Initial proof‐of‐concept experiments combining electrochemical determinations, with the use of an air‐sampling cyclone, are also reported. 相似文献
163.
Matthew C. Davis 《合成通讯》2013,43(10):1343-1346
The synthesis of 4,4″‐dinitro‐p‐terphenyl is accomplished by double Suzuki cross‐coupling. The product was reduced catalytically to give 4,4″‐diamino‐p‐terphenyl in 75% overall yield. 相似文献
164.
S. Ruchirawat M. Chaisupakitsin N. Patranuwatana J. L. Cashaw V. E. Davis 《合成通讯》2013,43(13):1221-1228
Various simple tetrahydroisoquinoline alkaloids (Ia, b, c, IIa and IIIa, b, c) have been synthesized by the reaction of appropriate arylethylamines with paraformaldehyde or formaldehyde in formic acid. 相似文献
165.
Matthew C. Davis 《合成通讯》2013,43(20):3519-3528
A rapid method to prepare 1,3,5‐triaminobenzene and its derivatives is the tris‐Curtius rearrangment of 1,3,5‐benzenetricarboxylic acid. The hazards associated with the acyl azide route are minimized by using 1,2‐dichloroethane as solvent. A second method that avoids acyl azide preparation uses diphenylphosphoryl azide to yield the tricarbamate in one step. 相似文献
166.
A solvent‐free Claisen condensation between isophorone or verbenone on two para‐hydroxyethylaminobenzaldehydes is described. The method provides the condensation products quickly and, in most cases, without chromatography. 相似文献
167.
A novel synthetic method for preparing diaminodiamondoids from diazidodiamondoids starting from the hydrocarbons is described. 相似文献
168.
Matthew C. Davis 《合成通讯》2013,43(4):654-663
Two hydroxymethyl-substituted monomers of diaminodiphenyloxybenzene were synthesized in three or four steps in 95% and 74% overall yields, respectively. 相似文献
169.
Kishor R. Shah Royston H. Filby Albert I. Davis 《International journal of environmental analytical chemistry》2013,93(1):63-73
Thermal neutron activation analysis, a high-resolution Ge(Li) gamma-ray spectrometer, and an IBM 360/67 digital computer were used to determine the concentration of Na, K, Sc, Cr, Mn, Fe, Co, Cu, Zn, Se, Br, Rb, Sb, Cs, and Hg in ground coffee and tea. This nondestructive multielement technique requires neither pre- nor postirradiation chemistry and eliminates problems of reagent contamination. The method is simple, precise and sensitive to 15 elements. Interferences from fast neutron (n, p) and (n, α) reactions are small and, if necessary, corrections may be applied easily. This technique can be applied to percolated tea and coffee. 相似文献
170.
Vipul Gupta Joshua A. Tuscano Naomi R. Romriell Robert C. Davis Matthew R. Linford 《Surface and interface analysis : SIA》2014,46(2):106-108
An important aspect of the robustness of an electronic device is its ability to resist water, fingerprints, dirt, and smudges that may compromise its ability to function and/or the information within it. Here, we report a chemical analysis by ToF‐SIMS, wetting, and XPS of the surfaces in a commercially available Apple iPod nano (8GB, MC525LL/A), which showed good resistance to its environment. This analysis reveals that the front panel (touchscreen) of the device is coated with a low free energy fluorinated polymer that may consist of short segments of a fluorinated hydrocarbon connected through ether linkages. No other part of the device appears to have this hydrophobic coating. A plasma treatment of the device leads to a deterioration of its performance. This work demonstrates how different analytical techniques can complement each other and contribute to a better understanding of a surface or a material. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献