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M. It (m + it)
Selected AbstractsHighly Selective and Sensitive Tin(II) Membrane Electrode Based on a New Synthesized Schiff's BaseELECTROANALYSIS, Issue 7 2009Morteza Hosseini Abstract Studies on complex formation of tris(3-(2-hydroxybenzophenone)propyl)amine (THPA) with a number of metal ions in acetonitrile solution revealed the occurrence of a selective 1,:,1 complexation of the proposed ligand with Sn2+ ion. Consequently, THPA was used as a suitable neutral ionophore for the preparation of a polymeric membrane-selective electrode. The electrode exhibits a Nernstian behavior with a slope of 29.4±0.3,mV per decade and a detection limit of 2.0×10,7 M. It also showed a good selectivity for Sn2+ ions in comparison with some of group A and B metal ions over a wide concentration range of 5.0×10,7,1.0×10,1 M. Improved selectivity was achieved compared to the best selectivity recently reported by other authors for tin(II). The electrode was successfully applied to the determination of Sn2+ ion in waste water and various canned products. [source] Inorganic reactions of iodine(+1) in acidic solutionsINTERNATIONAL JOURNAL OF CHEMICAL KINETICS, Issue 9 2004Guy Schmitz We present a thorough analysis of the former works concerning the hydrolysis of iodine and its mechanism in acidic or neutral solutions and recommend values of equilibrium and kinetic constants. Since the literature value for the reaction H2OI+ , HOI + H+ appeared questionable, we have measured it by titration of acidic iodine solutions with AgNO3. Our new value, K(H2OI+ , HOI + H+) , 2 M at 25°C, is much larger than accepted before. It decreases slowly with the temperature. We have also measured the rate of the reaction 3HOI , IO3, + 2I, + 3H+ in perchloric acid solutions from 5 × 10,2 M to 0.5 M. It is a second order reaction with a rate constant nearly independent on the acidity. Its value is 25 M,1 s,1 at 25°C and decreases slightly when the temperature increases, indicating that the disproportionation mechanism is more complicated than believed before. An analysis of the studies of this disproportionation in acidic and slightly basic solutions strongly supports the importance of a dimeric intermediate 2HOI , I2O·H2O in the mechanism. © 2004 Wiley Periodicals, Inc. Int J Chem Kinet 36:480,493, 2004 [source] M and 1H NMR, ionic motions and phase transitions in proton conducting MHSO4 (M = K, Rb, Cs, and NH4) single crystalsPHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 12 2005Ae Ran Lim Abstract The M and 1H spin,lattice relaxation rates in MHSO4 (M = K, Rb, Cs, and NH4) single crystals were measured over a wide temperature range. The temperature dependences of the 1H spin,lattice relaxation rates in RbHSO4 and NH4HSO4 can be explained by using the Bloembergen,Purcell,Pound theory while the temperature dependence of the 1H spin,lattice relaxation rate in KHSO4 cannot. Also, the relaxation process for M in MHSO4 crystals differs depending on M. It is well known that the characteristic features of MHSO4 crystals depend on whether M is K, Rb, Cs or NH4; specifically, NH4HSO4 and RbHSO4 exhibit ferroelectricity but KHSO4 and CsHSO4 do not. Consequently, although the MHSO4 crystals considered here are all members of the alkali acid sulfate family, our relaxation rate results varied depending on the mechanism of the ionic motion. This suggests that the differences in the chemical properties of M (= K, Rb, Cs, and NH4) are responsible for the variations of the natures of the phase transitions in these crystals. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Free space quantum key distribution: Towards a real life applicationFORTSCHRITTE DER PHYSIK/PROGRESS OF PHYSICS, Issue 8-10 2006H. Weier Abstract Quantum key distribution (QKD) [1] is the first method of quantum information science that will find its way into our everyday life. It employs fundamental laws of quantum physics to ensure provably secure symmetric key generation between two parties. The key can then be used to encrypt and decrypt sensitive data with unconditional security. Here, we report on a free space QKD implementation using strongly attenuated laser pulses over a distance of 480 m. It is designed to work continuously without human interaction. Until now, it produces quantum keys unattended at night for more than 12 hours with a sifted key rate of more than 50 kbit/s and a quantum bit error rate between 3% and 5%. [source] GLACIATION OF MT ALLEN, STEWART ISLAND (RAKIURA): THE SOUTHERN MARGIN OF LGM GLACIATION IN NEW ZEALANDGEOGRAFISKA ANNALER SERIES A: PHYSICAL GEOGRAPHY, Issue 2 2009MARTIN S. BROOK ABSTRACT. The origin of two ridges on the eastern slopes of Mt Allen, southern Stewart Island, has remained equivocal, with differences of opinion over the exact process-mechanisms of formation. A variety of approaches was used to test a number of possible hypotheses about the origin of the ridges. These include topographic and spatial positioning, geomorphology, sedimentology and palaeoclimatological extrapolations to reconstruct two small former cirque glaciers with equilibrium line altitudes (ELAs) of c. 600 m. It would appear the two ridges reflect a glacial origin, the glaciers interpreted as forming during the Last Glacial Maximum (LGM) in New Zealand. Whilst glaciation during this time (18,19 ka) was extensive in the Southern Alps, the restricted nature of glaciation on Mt Allen suggests the low altitude restricted glaciation to niche sites on the lee side of upland areas. [source] The fin whale Balaenoptera physalus (L. 1758) in the Mediterranean SeaMAMMAL REVIEW, Issue 2 2003GIUSEPPE NOTARBARTOLO-DI-SCIARA ABSTRACT 1.,The ecology and status of fin whales Balaenoptera physalus in the Mediterranean Sea is reviewed. The species' presence, morphology, distribution, movements, population structure, ecology and behaviour in this semi-enclosed marine region are summarized, and the review is complemented with original, previously unpublished data. 2.,Although the total size of the fin whale population in the Mediterranean is unknown, an estimate for a portion of the western basin, where most of the whales are known to live, was approximately 3500 individuals. High whale densities, comparable to those found in rich oceanic habitats, were found in well-defined areas of high productivity. Most whales concentrate in the Ligurian-Corsican-Provençal Basin, where their presence is particularly noticeable during summer; however, neither their movement patterns throughout the region nor their seasonal cycle are clear. 3.,Based on genetic studies, fin whales from the Mediterranean Sea are distinct from North Atlantic conspecifics, and may constitute a resident population, separate from those of the North Atlantic, despite the species' historical presence in the Strait of Gibraltar. Fin whales are known to calve in the Mediterranean, with births peaking in November but occurring at lower rates throughout the year. They feed primarily on krill Meganyctiphanes norvegica which they capture by diving to depths in excess of 470 m. It is suggested that the extensive vertical migratory behaviour of its main prey may have influenced the social ecology of this population. 4.,Known causes of mortality and threats, including collisions with vessels, entanglement in fishing gear, deliberate killing, disturbance, pollution and disease, are listed and discussed in view of the implementation of appropriate conservation measures to ensure the species' survival in the region. [source] Evidence for hyperparasitism of coffee rust (Hemileia vastatrix) by the entomogenous fungus, Lecanicillium lecanii, through a complex ecological webPLANT PATHOLOGY, Issue 4 2009J. Vandermeer The entomogenous fungus, Lecanicillium lecanii is hyperparasitic on Hemileia vastatrix, the cause of coffee leaf rust in the laboratory, and has frequently been observed attacking it in the field. The existence of a complex ecological web involving the spatially clustered mutualism of an ant (Azteca instabilis) with a scale insect (Coccus viridis), where the scale insect was infected by L. lecanii, prompted a search for a spatial correlation between the attack of L. lecanii on the scale insect and the incidence of rust in a commercial coffee crop. A weak but statistically significant effect of hyperparasitic control of coffee rust was observed on two distinct scales: in a 45-ha plot and on a scale of approximately 10 m. It was concluded that this effect was linked to an indirect effect of the ant,coccid mutualism, where L. lecanii was a parasite of the coccid. [source] | ||||||||||||||||