Magnetic Relaxation Probing of the State of Diheptyl Dithiophosphate Ions in Water and Aqueous Triton X-100 Solutions

The nuclear magnetic relaxation was used to study the state of diheptyl dithiophosphoric acid (D7DTP, L7) anions in water and aqueous solutions of the nonionic surfactant, Ttiton X-100, at 298 K in the presence of paramagnetic probes, Mn2+ ions. It was found that increase in the spin-lattice relaxation rate of water protons is caused by formation of simple and mixed (with surfactant) aggregates of D7DTP. Unlike the Mn2+-sodium dodecyl sulfate -Triton X-100 system, studied previously an influence of a probe concentration was found at surfactant concentration close to the CMC. It was suggested that two types of mixed species containing diheptyl dithiophosphate ions, Mn(II), and nonionic surfactant can be formed: micellar aggregates, {Mn(L7)2(TX)}, and polynuclear associates, [Mnx(L7)y(tx)z]. The associates likely contain surfactant in the form of monomers (tx)

High pressures, low temperatures, and magnetic field effects on AgFeAsSe3 and AgFeSbSe3 properties

A procedure for synthesizing AgFeAsSe3 and AgFeSbSe3 is presented, and their electric and magnetic properties are investigated over a wide range of temperatures, pressures, and magnetic field variation. At 100-400K, the samples are characterized by semiconductor properties. Under pressures of ∼25 and ∼24 GPa, the electric properties of AgFeAsSe 3 and AgFeSbSe3 change greatly. © 2013 Allerton Press, Inc

Calibration of the NEVOD-EAS array for detection of extensive air showers

In this paper we discuss the calibration of the NEVOD-EAS array which is a part of the Experimental Complex NEVOD, as well as the results of studying the response features of its scintillation detectors. We present the results of the detectors energy calibration, performed by comparing their response to different types of particles obtained experimentally and simulated with the Geant4 software package, as well as of the measurements of their timing resolution. We also discuss the results of studies of the light collection non-uniformity of the NEVOD-EAS detectors and of the accuracy of air-shower arrival direction reconstruction, which have been performed using other facilities of the Experimental Complex NEVOD: the muon hodoscope URAGAN and the coordinate-tracking detector DECOR.Comment: 16 pages, 17 figures, To be submitted to Nuclear Instruments and Methods

Magnetic Relaxation Probing of the State of Diheptyl Dithiophosphate Ions in Water and Aqueous Triton X-100 Solutions

The nuclear magnetic relaxation was used to study the state of diheptyl dithiophosphoric acid (D7DTP, L7) anions in water and aqueous solutions of the nonionic surfactant, Ttiton X-100, at 298 K in the presence of paramagnetic probes, Mn2+ ions. It was found that increase in the spin-lattice relaxation rate of water protons is caused by formation of simple and mixed (with surfactant) aggregates of D7DTP. Unlike the Mn2+-sodium dodecyl sulfate -Triton X-100 system, studied previously an influence of a probe concentration was found at surfactant concentration close to the CMC. It was suggested that two types of mixed species containing diheptyl dithiophosphate ions, Mn(II), and nonionic surfactant can be formed: micellar aggregates, {Mn(L7)2(TX)}, and polynuclear associates, [Mnx(L7)y(tx)z]. The associates likely contain surfactant in the form of monomers (tx)

Magnetic Relaxation Probing of the State of Diheptyl Dithiophosphate Ions in Water and Aqueous Triton X-100 Solutions

The nuclear magnetic relaxation was used to study the state of diheptyl dithiophosphoric acid (D7DTP, L7) anions in water and aqueous solutions of the nonionic surfactant, Ttiton X-100, at 298 K in the presence of paramagnetic probes, Mn2+ ions. It was found that increase in the spin-lattice relaxation rate of water protons is caused by formation of simple and mixed (with surfactant) aggregates of D7DTP. Unlike the Mn2+-sodium dodecyl sulfate -Triton X-100 system, studied previously an influence of a probe concentration was found at surfactant concentration close to the CMC. It was suggested that two types of mixed species containing diheptyl dithiophosphate ions, Mn(II), and nonionic surfactant can be formed: micellar aggregates, {Mn(L7)2(TX)}, and polynuclear associates, [Mnx(L7)y(tx)z]. The associates likely contain surfactant in the form of monomers (tx)

Magnetic Relaxation Probing of the State of Diheptyl Dithiophosphate Ions in Water and Aqueous Triton X-100 Solutions

The nuclear magnetic relaxation was used to study the state of diheptyl dithiophosphoric acid (D7DTP, L7) anions in water and aqueous solutions of the nonionic surfactant, Ttiton X-100, at 298 K in the presence of paramagnetic probes, Mn2+ ions. It was found that increase in the spin-lattice relaxation rate of water protons is caused by formation of simple and mixed (with surfactant) aggregates of D7DTP. Unlike the Mn2+-sodium dodecyl sulfate -Triton X-100 system, studied previously an influence of a probe concentration was found at surfactant concentration close to the CMC. It was suggested that two types of mixed species containing diheptyl dithiophosphate ions, Mn(II), and nonionic surfactant can be formed: micellar aggregates, {Mn(L7)2(TX)}, and polynuclear associates, [Mnx(L7)y(tx)z]. The associates likely contain surfactant in the form of monomers (tx)

Fibre Optic Readout of Microcantilever Arrays for Fast Microorganism Growth Detection

We present a fibre-optic-based device for the automated readout of microcantilever arrays for fast microorganism growth detection. We determined the ability of our device to track shifts in resonance frequency due to an increase in mass on the cantilever surface or changes in mechanical stiffness. The resonance frequency response of 7 μm thick agarose-functionalised cantilevers was tracked as humidity levels were varied revealing a mass responsivity of ~51±1 pg/Hz. The resonance response of microcantilevers coated with Aspergillus niger (A. niger) spores was monitored for >48 h revealing a growth detection time of >4 h. The growth of mycelium along the cantilevers surface is seen to result in an increase in resonance frequency due to the reinforcement of the cantilever structure. The use of our fibre optic detection technique allows data to be recorded continuously and faster than previously reported

Digital processing of multi-mode nano-mechanical cantilever data

Nanomechanical sensors based on cantilever technology allow the measurement of various physical properties. Here we present a software for the comprehensive analysis of such data. An example for the combined measurement of mass and surface stress is presented

Influence of the composition on the electrical properties of amorphous chalcogenides AgGe1+x As1-x S-3

This article is devoted to the synthesis and examination of the electrical properties of amorphous chalcogenides AgGe 1 + xAs 1 - xS 3 (x = 0. 1, 0. 4-0. 6, 0. 9) at low temperatures. The studies are performed in order to obtain materials with improved characteristics (an increase in the fraction of the ionic transfer, a decrease in the temperatures of its emergence, and an increase in conductivity). The synthesized compounds are electron-ion conductors. An increase in the Ge fraction leads to an increase in the temperature corresponding to the onset of ionic transport and to a decrease in conductivity. © 2012 Pleiades Publishing, Ltd