On the interdiffusion-based quantum cascade laser

Design procedure for the active region of current pumped quantum cascade laser is proposed, so to achieve maximal gain. Starting with an arbitrary smooth potential, a family of isospectral Hamiltonians with predefined energy spectrum is generated using the inverse spectral theory. By varying the relevant control parameter the potential shape is varied, inducing changes in transition dipole moments and electron–phonon scattering times, and the optimal potential which gives the largest gain is thus found. For purpose of realization, a simple step quantum-well structure with just a few layers is then designed so that in the post-growth heating-induced layer interdiffusion, it will acquire a shape as close as possible to the optimal smooth potentia

Variability and Correlations of Some Investigated Traits of Perennial Ryegrass Populations

Perennial ryegrass (Lolium perenne) is one of the most important perennial forage grasses for temperate climates. It is a highly productive grass with the highest nutritive value (Sokolovi et al., 2002). In Serbia, breeders have developed perennial ryegrass cultivars with high stabile yield and quality with different times of maturity and resistance to drought and frost. The initial breeding material were usually wild populations (Charmet et. al., 1996) with high variability and adaptability. These characteristics lend themselves for selection of superior genotypes. But breeding for some important agronomic traits may influence others. This relationship between traits and breeding population variability is the objective of this article

Fiber-optic interferometric sensor of magnetic field for structural health monitoring

AbstractIn this paper we report on results of measurement of AC and DC magnetic field by fiber-optic interferometric sensor. Principle of operation is based on change of length of optical path cavity between the magnetostrictive wire and fiber-optic tip. Any change of the outside magnetic field causes elongation or contraction of the sensing wire. Using a fiber-optic sensing configuration based on single-mode 3×3 coupler and low-coherence interferometry we were able to read the instant separation between the wire and fiber ends with accuracy of about 50 nm. This separation corresponds with the intensity of the magnetic field in the range of 50 nT to 800 μT what is measured by using well calibrated magnetometer. The sensor is dedicated for on-line structural health monitoring of composite materials made of carbon reinforced epoxy matrix with integrated magnetic particles. Due to final purpose to be embedded in the structure, the sensor is designed to have small overall size of about 250 μm in outside diameter

4-Lump kinetic model for hydrotreated gas oil catalytic cracking

This study has monitored the influence of one of the hydrodesulphurisation process parameters - H2/CH ratio on the properties of three catalytic cracking products (gas, petrol, light cyclic oil, and heavy cyclic oil ). The microactivity test (MAT) was applied to all kinetic measurements. A 4-lump, non-isothermal and non-stationary kinetic model for the fixed, plug-flow MAT reactor was developed to model catalytic cracking of hydrotreated gas oil. Kinetic constants were estimated by the Nelder Mead method. The product yields predicted by the model showed good confirmity with experimental data

Period Batch Control - A Production Planning System Applied to Virtual Manufacturing Cells

Period Batch Control (PBC) system has been known for its implementation with the classical group technology (GT) cells, and it has been known for its simplicity. The main production planning decisions concern the choice of the period length and the stage number and contents. Also, in order to better integrate the production planning with the application of GT cells at the shop floor, the concept of virtual manufacturing cells has been applied. Since virtual cells configurations are changing periodically, a model for implementing the PBC system into virtual manufacturing cells environment is developed. The model enables alignment of the PBC principles and rules with virtual cell design goals. Model is tested on the case study of furniture production. With the use of scheduling software, different scheduling rules were simulated for four production weeks. The experimental results from these for production weeks show how the choice of PBC parameters impacts the virtual cells configurations, machine sharing and utilization

Співвідношення навчання і виховання у філософії педагогіки Памфіла Юркевича

24th General Meeting of the European-Grassland-Federation -- JUN 03-07, 2012 -- Lublin, POLANDWOS: 000361159300041Italian ryegrass monoculture and mixtures with red clover (sowing ratios 75:25%, 50:50% and 25:75%) were established in the spring of 2008 at the Institute for Animal Husbandry, Belgrade, with the aim to analyse the possibilities of managing the N supply. There were four N rates for Italian ryegrass monoculture: 0, 100, 150 and 200 kg ha(-1), whilst no N fertilizer was applied to the mixture plots. The trial was carried out during 2008-2010 and the highest total DM yield was obtained with 200 kg N ha(-1), similar to that of the ryegrass-clover mixtures. Ryegrass contributed less to the total yield in the mixtures, because it had lower ratios in the structure of swards than those used at sowing. An Italian ryegrass-red clover sward may have advantages over a pure Italian ryegrass sward fertilized by high rates of N, providing high yield with a more sustainable land-use system.Kuhn, Ministerstwo Rolnictwa Rozwoju Wsi, Lubelski Wegiel Bogdanka S A, Karol Kania Synowie, Rolimpex, Dept Rolnictwa Srodowiska Urzedu Marszalkowskiego Wojewodztwa, Lubelskiego, Linia Hutnicza Szerokotorowa, Powiat Bilgorajski, Centinas, DSV Polska, Perla Browary Lubelskie, Lubella, Uniwersytet Przyrodniczy w Lublinie, Miasto Lublin, Apis, Herbapol Lublin S A, OSM Krasnystaw, Powiat Krasnostawski, Powiat Lubelski, Powiat Krasnystaw, Lubelska Izba Rolnicza, Gmina Krasnystaw, Urzad Miasta Krasnysta

Genomics-Based Insights Into the Biosynthesis and Unusually High Accumulation of Free Fatty Acids by Streptomyces sp NP10

Schneider O, Ilic-Tomic T, Rückert C, et al. Genomics-Based Insights Into the Biosynthesis and Unusually High Accumulation of Free Fatty Acids by Streptomyces sp NP10. FRONTIERS IN MICROBIOLOGY. 2018;9: 10.Streptomyces sp. NP10 was previously shown to synthesize large amounts of free fatty acids (FFAs). In this work, we report the first insights into the biosynthesis of these fatty acids (FAs) gained after genome sequencing and identification of the genes involved. Analysis of the Streptomyces sp. NP10 draft genome revealed that it is closely related to several strains of Streptomyces griseus. Comparative analyses of secondary metabolite biosynthetic gene clusters, as well as those presumably involved in FA biosynthesis, allowed identification of an unusual cluster C12-2, which could be identified in only one other S. griseus-related streptomycete. To prove the involvement of identified cluster in FFA biosynthesis, one of its three ketosynthase genes was insertionally inactivated to generate mutant strain mNP10. Accumulation of FFAs in mNP10 was almost completely abolished, reaching less than 0.01% compared to the wild-type strain. Cloning and transfer of the C12-2 cluster to the mNP10 mutant partially restored FFA production, albeit to a low level. The discovery of this rare FFA biosynthesis cluster opens possibilities for detailed characterization of the roles of individual genes and their products in the biosynthesis of FFAs in NP10