50 research outputs found
Generation of neutral atomic beams utilizing photodetachment by high power diode laser stacks
We demonstrate the use of high power diode laser stacks to photodetach fast
hydrogen and carbon anions and produce ground term neutral atomic beams. We
achieve photodetachment efficiencies of 7.4\% for H at a beam energy
of 10\,keV and 3.7\% for C at 28\,keV. The diode laser systems used
here operate at 975\,nm and 808\,nm, respectively, and provide high continuous
power levels of up to 2\,kW, without the need of additional enhancements like
optical cavities. The alignment of the beams is straightforward and operation
at constant power levels is very stable, while maintenance is minimal. We
present a dedicated photodetachment setup that is suitable to efficiently
neutralize the majority of stable negative ions in the periodic table
High-throughput method for detection and quantification of lesions on leaf scale based on trypan blue staining and digital image analysis
Background: Field-grown leafy vegetables can be damaged by biotic and abiotic factors, or mechanically damaged
by farming practices. Available methods to evaluate leaf tissue damage mainly rely on colour diferentiation between
healthy and damaged tissues. Alternatively, sophisticated equipment such as microscopy and hyperspectral cameras
can be employed. Depending on the causal factor, colour change in the wounded area is not always induced and,
by the time symptoms become visible, a plant can already be severely afected. To accurately detect and quantify
damage on leaf scale, including microlesions, reliable diferentiation between healthy and damaged tissue is essential.
We stained whole leaves with trypan blue dye, which traverses compromised cell membranes but is not absorbed in
viable cells, followed by automated quantifcation of damage on leaf scale.
Results: We present a robust, fast and sensitive method for leaf-scale visualisation, accurate automated extraction
and measurement of damaged area on leaves of leafy vegetables. The image analysis pipeline we developed automatically identifes leaf area and individual stained (lesion) areas down to cell level. As proof of principle, we tested the methodology for damage detection and quantifcation on two feld-grown leafy vegetable species, spinach and Swiss
chard.
Conclusions: Our novel lesion quantifcation method can be used for detection of large (macro) or single-cell
(micro) lesions on leaf scale, enabling quantifcation of lesions at any stage and without requiring symptoms to be in the visible spectrum. Quantifying the wounded area on leaf scale is necessary for generating prediction models for economic losses and produce shelf-life. In addition, risk assessments are based on accurate prediction of the relationship between leaf damage and infection rates by opportunistic pathogens and our method helps determine the
sevn.erity of leaf damage at fne resoluti
Energy-sensitive imaging detector applied to the dissociative recombination of D2H+
We report on an energy-sensitive imaging detector for studying the
fragmentation of polyatomic molecules in the dissociative recombination of fast
molecular ions with electrons. The system is based on a large area (10 cm x 10
cm) position-sensitive, double-sided Si-strip detector with 128 horizontal and
128 vertical strips, whose pulse height information is read out individually.
The setup allows to uniquely identify fragment masses and is thus capable of
measuring branching ratios between different fragmentation channels, kinetic
energy releases, as well as breakup geometries, as a function of the relative
ion-electron energy. The properties of the detection system, which has been
installed at the TSR storage ring facility of the Max-Planck Institute for
Nuclear Physics in Heidelberg, is illustrated by an investigation of the
dissociative recombination of the deuterated triatomic hydrogen cation D2H+. A
huge isotope effect is observed when comparing the relative branching ratio
between the D2+H and the HD+D channel; the ratio 2B(D2+H)/B(HD+D), which is
measured to be 1.27 +/- 0.05 at relative electron-ion energies around 0 eV, is
found to increase to 3.7 +/- 0.5 at ~5 eV.Comment: 11 pages, 12 figures, submitted to Physical Review
Электроснабжение установки перекачки нефти п. Пионерный ОАО «Томскнефть»
РЕФЕРАТ
Выпускная квалификационная работа 149 с., 23 рис., 32 табл., 29 источников, 6 прил.
Ключевые слова: нефтепровод, насос, электрооборудование, схема электроснабжения, линия, сеть, электроприемник, нагрузка, оборудование, защита, ток, напряжение, мощность.
Объектом исследования является электрическая часть УПН п. Пионерный ОАО «Томскенефть».
Цель работы – проектирование схемы электроснабжения предприятия, выбор оборудования.
В процессе исследования проводился сбор исходных данных в ходе производственной практики на объекте исследования.
В результате была спроектирована схема электроснабжения от подстанции энергосистемы, до конечного электроприемника. Были выбраны кабели и провода, коммутационное оборудование, были сделаны необходимые проверки. Также результатом работы сталESSAY
Final qualifying work 149 p., 23 fig., 32 tab., 29 sources, 6 adj.
Keywords: oil, pump, electrical equipment, power supply circuit, line, network, power-consuming equipment, load equipment, protection, current, voltage, power.
The object of research is the electrical part of UPN claim. Pionerny of "Tomskeneft".
The purpose of work - designing enterprise power scheme, the choice of equipment.
The study was conducted to collect baseline data in the course of practical training on the subject of the study.
As a result, power supply circuit has been designed from the substation grid, appliance, to the end. Were selected cables and wires, switching equipment, the necessary checks have been made. It is also the result of the work became an economic calculation of capital costs for the con