Magnetotransport in Double Quantum Well with Inverted Energy Spectrum: HgTe/CdHgTe

We present the first experimental study of the double-quantum-well (DQW) system made of 2D layers with inverted energy band spectrum: HgTe. The magnetotransport reveals a considerably larger overlap of the conduction and valence subbands than in known HgTe single quantum wells (QW), which may be regulated by an applied gate voltage $V_g$. This large overlap manifests itself in a much higher critical field $B_c$ separating the range above it where the quantum peculiarities shift linearly with $V_g$ and the range below with a complicated behavior. In the latter case the $N$-shaped and double-$N$-shaped structures in the Hall magnetoresistance $\rho_{xy}(B)$ are observed with their scale in field pronouncedly enlarged as compared to the pictures observed in an analogous single QW. The coexisting electrons and holes were found in the whole investigated range of positive and negative $V_g$ as revealed from fits to the low-field $N$-shaped $\rho_{xy}(B)$ and from the Fourier analysis of oscillations in $\rho_{xx}(B)$. A peculiar feature here is that the found electron density $n$ remains almost constant in the whole range of investigated $V_g$ while the hole density $p$ drops down from the value a factor of 6 larger than $n$ at extreme negative $V_g$ to almost zero at extreme positive $V_g$ passing through the charge neutrality point. We show that this difference between $n$ and $p$ stems from an order of magnitude larger density of states for holes in the lateral valence band maxima than for electrons in the conduction band minimum. We interpret the observed reentrant sign-alternating $\rho_{xy}(B)$ between electronic and hole conductivities and its zero resistivity state in the quantum Hall range of fields on the basis of a calculated picture of magnetic levels in a DQW.Comment: 15 pages, 13 figure

Peningkatan Kadar Sulfur Dan Selenium Hijauan Zea Mays Saccharata Oleh Pemupukan Fosfor Dalam Suspensi Fermentasi Acetobacter-saccharomyces Sulfur and Selenium Content Improvement of Zea Mays Saccharata with Phosphorus Fertilization in the Fermented Acetobacter-saccharomyces Solution

A greenhouse experiment was conducted during 6 weeks on acid latosolic soil and low phosphorus availability. A completely randomized design with 5 treatments and 4 replicates was used. The treatments were control, RP, SP, RP+FSAS, and SP+FSAS. Phosphorus fertilizer level was 200 kg P2O5/ha (2.96 g RP/pot or 2.22 g SP/pot). Sweet corn was cut and measured for S and Se content on 6 weeks after planting. All data were analyzed by the GLM procedure of SAS. Significant differences among the treatments were calculated by DMRT. The results show that SP+FSAS increased S and Se content significantly higher compared to control and RP (

PENINGKATAN KADAR LOVASTATIN ANGKAK OLEH Monascuspurpureus KO-KULTUR DENGAN Endomycopsis Burtontt [Improvement of Lovastatin Angkak Production by Monascus Purpureus Strains Co-Cultured with Endomycopsis Burtonii]

Lovastatin is a bioactive material of statin groups and has been used to reduce cholesterol through inhibiting HMG Co-A reductase enzyme activities. Three indigenous strains of Monascus purpureus and three mutans were used in this study produced lovastatin at the range of 0,1 - 1,42%. The objectives of this study were to increase lovastatin productions by co-cultured with several concentrations of Endomycopsis burtonii. M. purpureus (10 cfu/ml) was co-cultured with various concentrations of E. burtonii (10M0 ) cfu/ral at three different feeding times (day 2, 4, and 6). Feeding times and concentrations of E. burtonii significantly increased production of lovastatin by four strains of M. purpureus (JMBA5K, AID, JMBA and TOS). The highest production of lovastatin was achieved by M. purpureus TOS co-cultured by E. burtonii at 10 cfu/ml added at day 6. Expression of the genes that responsible for lovastatin production were analyzed by PCR and RT-PCR method. The phenotypic character of M. purpureus TOS with high lovastatin production was conformed by the high intensity of its gene expression

The effect of Farmayod on nematodes of different trophic groups <i>in vitro</i> and <i>in vivo</i>

The purpose of the research is to study the effect of Farmayod on nematodes of different trophic groups, including rootknot nematode larvae, in vitro and in vivo.Materials and methods. The object of the research were larvae of the root-knot nematode Meloidogyne incognita obtained from the roots of infected plants from the Vladimir Region. The study of the effect of Farmayod in three concentrations was carried out in laboratory, using the biotest method on pumpkin plants. The effect of liquid Farmayod on the viability of nematodes of different trophic groups was studied in vitro and in vivo.Results and discussion. Liquid 0.1% Farmayod showed phytotoxicity, and not a single plant germinated. The drug in the form of a 0.01% solution showed phytotoxicity but to a lesser extent. The root system was less developed (60%) than in the control. The plant height was also 15% less. Farmayod at a concentration of 0.01% did not have phytotoxicity and reduced meloidoginosis versus the control. The biological efficacy of such dose was 56% higher, and the plant height was 30% more. The drug at a concentration of 0.01% had no effect on the plants damaged by meloidoginosis due to its phytotoxicity and poorly developed root system of the plants versus the control. Thus, at low concentrations, Farmayod acts on plants as a trace element necessary for plant vegetation, which affected the size of the plant. On the other hand, it can significantly reduce the infection of pumpkin roots with root-knot nematodes. Since this concentration is not toxic to nematodes, it can be assumed that the drug affects the nematode indirectly through the plant

Spinodal decomposition of off-critical quenches with a viscous phase using dissipative particle dynamics in two and three spatial dimensions

We investigate the domain growth and phase separation of hydrodynamically-correct binary immiscible fluids of differing viscosity as a function of minority phase concentration in both two and three spatial dimensions using dissipative particle dynamics. We also examine the behavior of equal-viscosity fluids and compare our results to similar lattice-gas simulations in two dimensions.Comment: 34 pages (11 figures); accepted for publication in Phys. Rev.

Reduction of Railway Disorders Intensity Due to Improvement of Line Plan Parameters During Pasportization of Curves

Purpose. The work is aimed to reduce the intensity of the track disorder by improving the line plan parameters, ultimately ensuring the safety, smoothness and comfort of driving in the directions of high-speed train traffic. Methodology. To obtain initial data on the parameters of the plan of existing railways, the authors reviewed the world literature on the topic of the study, as well as monitored the railway track operation on the basis of technical passports of track distances. It is known that the accepted mathematical models of the existing plan use the assumption that three adjacent points of the curve lie on a circle. On this principle, the work of flattener machine for switches is based. As a result of corrective works to reduce the amount of shifts, the curve does not correspond to the initial passport data. The methodology involves the analysis and systematization of data to establish appropriate dependencies and build graphs. Findings. Inaccurate determination of the curve parameters results in unjustified speed restrictions on or large volumes of flattening works. Therefore, the proposals have been developed to reduce the intensity of track disorders by bringing the curve parameters to the regulatory requirements in force in Ukraine in the areas of high-speed train traffic. They follow from the analysis of the method of shooting curves used in track distances. The influence of accuracy of the obtained data on the establishment of the curve parameters and the permissible train speeds is identified. The recommendations received in the work will contribute to the effectiveness of design decisions, will determine the quality of the railway reconstruction project. Originality. Scientific approaches to estimating the state of curves, determining their rational parameters and permissible speed in the areas of high-speed train traffic in Ukraine have been further developed. Practical value. The obtained results will be useful for measures to improve the smoothness of train movement, increasing the speed and comfort of driving in the curved track sections, especially in the areas of high-speed train traffic