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541.
Two novel complexes,[(C9H18NS2)3Sb(III)](1) and [(C9H18NS2)3Bi(III)](2),were synthesized and characterized by elemental analysis,IR,TG and X-ray single-crystal diffraction.Both 1 and 2 crystallize in the monoclinic system,P21/c space group.The data for 1:a = 1.6964(3),b = 1.02149(17),c = 2.5650(3) nm,β = 121.824(8)°,Z = 4,V = 3.7766(10) nm3,Dc = 1.293 g·cm-3,F(000) = 1536,μ = 1.082 mm-1,the final R = 0.0500,wR = 0.1562 and S =1.072.The data for 2:a = 1.6802(9),b = 1.0256(6),c = 2.5083(10) nm,β = 121.77(3)°,Z = 4,V = 3.675(3) nm3,Dc = 1.486 g·cm-3,F(000) = 1664,μ = 5.159 mm-1,the final R = 0.0481,wR = 0.1055 and S =1.076.The coordinated geometry of the central M(III) with six sulfur atoms from three ligands is a distorted pentagonal pyramid configuration.The dimer structural system is formed by the weak interactions of M…S and C-H…S between two molecules.The complexes were valued for their antibacterial activities by agar-streak method.It was found that 1 is active against the four test bacterial organisms. 相似文献
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《Analytical letters》2012,45(5):711-724
Abstract A flow injection potentiometric procedure is proposed for the determination of acidity of several samples using an antimony/ antimony oxide electrode. The ΔE/pH curve in phosphate buffer solutions in the pH range from 1.58 to 12.00 showed a linear sub-Nernstian behavior with an operational slope S =-42.1mV/pHc and a conditional standard potential of 264.8mV. This flow potentiometric electrode responds linearly to low acidity variations of dilute acetic acid solutions from 3.16 to 100mM with a slope of 30.1mV/dec and analytical frequency of 23 results/h. Good reproducibility and an average standard deviation of ±0.5% was obtained. The application of this sensor for the determination of coke acidity and acetic acid in vinegar is reported. 相似文献
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《Analytical letters》2012,45(2):129-137
Abstract Hexachloroantimonate(V) and tetrachlorothallate(III) salts of Sevron Red L (C.I. Basic Red 17), Sevron Red GL (C.I. 11,085), Flavinduline O (C.I. 50,000) and Phenazinduline O have been applied in liquid-state ion-selective electrodes for the determination of antimony and thallium. The slope of potential versus pM graphs approach full Nernstian response in the range 10 M (Sb) and 10?6 M (T1) to 10?2 M. An unusual feature of the electrodes is their response to antimony(III) as well as to antimony(V). 相似文献
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Sandrine Rup 《Tetrahedron letters》2010,51(23):3123-3126
All the works reported about oxidative cleavage of olefins by the RuCl3/NaIO4 catalytic system have been performed in biphasic water/organic solvent(s). The first organic solvent-free oxidation of CC double bond by 2% RuCl3/4.1 equiv NaIO4/H2O is described here using both the emulsifier Aliquat® 336 and 20 kHz ultrasonic irradiation. 相似文献
550.
Falko Wachholz Heiko Duwensee Ralf Schmidt Michael Zwanzig Jan Gimsa Stefan Fiedler Gerd‐Uwe Flechsig 《Electroanalysis》2009,21(19):2153-2159
Gold nanostructuring of smooth gold disk‐electrodes has been performed by electrodeposition. FE‐SEM images indicate a strongly enlarged electrochemically active surface of the modified electrodes. This could be approved by the gold oxide reduction peak in cyclic voltammetry. The electrodes were also applied for sequence‐specific DNA detection. For this, complementary single stranded capture probes were immobilized on the electrodes and consecutively hybridized with complementary and noncomplementary [OsO4(bipy)]‐labeled DNA targets. We found that intermediate dehybridization steps did not decrease the sensitivity for the specific target. Moreover, the surface modification increased the voltammetric signal by an approx. factor of 9. Further, an enhanced linear calibration range was observed. The presented simple nanostructuring process holds great promise for many electrochemical sensor applications. 相似文献