Can an interplanetary magnetic field reach the surface of Venus?

We address the question of whether there is a possibility of an interplanetary magnetic field reaching Venus' surface by magnetic diffusion across the ionosphere. We present a model calculation, estimate the magnetic diffusion time at Venus, and find out that the typical diffusion timescale is in a range between 12 and 54 h, depending on the solar activity and the ionospheric magnetic field condition. The magnetic field can thus permeate Venus' surface and even its interior when the solar wind is stationary (i.e., no magnetic field reversal) on the timescale of half a day to several days.

Can interplanetary magnetic field reach the Venus surface?

The question is addressed if there is a possibility of interplanetary magnetic field reaching the Venus surface by magnetic diffusion across the ionosphere. We present a model calculation and estimate the magnetic diffusion time at Venus, and find out that the typical diffusion time scale is in a range between 11 and 40 h, depending on the solar activity and the ionospheric magnetic field condition. Magnetic field can thus permeate Venus surface and even Venus interior when the solar wind is stationary (i.e., no magnetic field reversal) on the time scale of half-a-day to several days.

DEVELOPMENT OF DNA BIOSENSOR BASED ON SILVER NANOPARTICLES UV-Vis ABSORPTION SPECTRA FOR Escherichia coli DETECTION

<p>In this research we reported the synthesis of oligonucleotide-silver nanoparticle (OSN) conjugates and demonstrated their use along with magnetic beads as biosensor for Escherichia coli detection under magnetic field condition. Oligonucleotide DNA probes were conjugated on silver nanoparticles using alkanethiols linker. Two kinds of alkanethiols linker, 11-mercaptoundodecanoic acid (11-MUDA) and 16-mercaptophexadecanoic acid (16-MHDA) were compared to get the best probe conjugation yield and OSN UV-Vis absorption spectra properties. Three different methods of Escherichia coli DNA isolation i.e. Chen and Kuo (1993), Phenol Chloroform Isoamylalcohol (PCI) extraction and boiling lysis were also compared to explore the performance of the biosensor towards the DNA target purity. Detection process through hybridization between the DNA probe and the target was carried out at 55oC for 1 hour incubation time. The results showed that 16-MHDA gave higher conjugation yield and higher OSN UV-Vis absorption spectra than 11-MUDA. The biosensor was able to detect the presence of the DNA target which was isolated from the three isolation methods. The best detection signal was achieved by Chen and Kuo isolation method in which it could detect the presence of the DNA target up to 1.3 ng/µL.</p><p><br /><strong>Keywords</strong>: DNA biosensor, Silver Nanoparticles, Escherichia coli</p>

A new method to realize high-throughput protein crystallization in a superconducting magnet

We present a new method for the realization of high-throughput protein crystallization screening using an array of 96 capillaries aligned in a circle. In this method, each capillary represents a single crystallization condition, and all capillaries experience an identical magnetic field condition.

Fabrication and Characterization of Micro-Patterned Magnetorheological Elastomeric Structures

This paper presents fabrication and characterization of micro-patterned magnetorheological elastomeric structures composed of magnetorheological fluid (MRF) sandwiched with magnetorheological elastomeric (MRE) materials. The MRE structures are made of polydimethylsiloxane (PMDS) with and without an additive of carbonyl iron (CI) particles with a size range of 6–9 um and the MRF is composed of silicon fluid mixed with the CI particles of the same size range. Three different SU-8 master molds of plain, longitudinal, and latitudinal patterns are constructed. Also, four MR elastomeric structures of different CI particle arrangements of isotropic MRE, anisotropic top-to-bottom-aligned MRE, anisotropic side-to-side-aligned MRE, and pure PDMS for each SU-8 master mold are fabricated. MRE structures are then characterized by using a tensile testing machine under a normal condition (off-state) and a low magnetic field condition (on-state). The tensile tests were performed to experimentally investigate their tunable properties. Later, the data gathered are compared for different conditions.

The Effects of Electromagnetic Stirring on Solidification Structure and Macrosegregation of Pb-Sn Alloy

The effects of different electromagnetic field and technological parameters on the microstructure and composition segregation of Pb-80%Sn alloy were studied. The results show that, both rotating and spiral magnetic field can improve the composition segregation ,refine grains of alloy. Moreover,the spiral magnetic field is more effective on improving composition homogenization and grain refining. The electromagnetic force distribution of spiral magnetic field is more helpful to form a well stirring in a larger zone and promote the formation of equiaxed grains, and the direction of the grain arrangement is much smaller. The technical parameters of spiral magnetic field have been optimized. It is found that, under the spiral magnetic field condition, when stirring time and exciting current exceeded a critical value, the size of the primary phase became larger. Therefore, there existed an optimum value of magnetic stirring parameters for the homogenization of component and refinement of grains.