134 research outputs found
Band structure and optical properties of germanium sheet polymers
The band structure of H-terminated Ge sheet polymers is calculated using density-functional theory in the local density approximation and compared to the optical properties of epitaxial polygermyne layers as determined from reflection, photoluminescence, and photoluminescence excitation measurements. A direct band gap of 1.7 eV is predicted and a near resonant excitation of the photoluminescence is observed experimentally close to this energy
Phosphorus donors in highly strained silicon
The hyperfine interaction of phosphorus donors in fully strained Si thin
films grown on virtual SiGe substrates with is
determined via electrically detected magnetic resonance. For highly strained
epilayers, hyperfine interactions as low as 0.8 mT are observed, significantly
below the limit predicted by valley repopulation. Within a Green's function
approach, density functional theory (DFT) shows that the additional reduction
is caused by the volume increase of the unit cell and a local relaxation of the
Si ligands of the P donor.Comment: 12 pages, 3 figure
Горизонтальные классификаторы. Основы теории и расчета: моногр.
Приведены технологические схемы получения строительных песков при
гидромеханизированной добыче, основные конструктивные схемы классификаторов,
используемых при получении строительных песков. Особое внимание уделено изучению
процесса взаимодействия проточной части горизонтального классификатора с
совокупностью твердых частиц, расположенных в горизонтальном ускоренном потоке
несущей среды. Выполнено математическое моделирование ускоренного движения
горизонтального потока и твердых частиц в пределах разнонаклонных поверхностей
горизонтального классификатора. Экспериментально изучено гравитационное осаждение
твердых частиц, рассмотренное в виде вертикальной и горизонтальной составляющих, а
также влияние стесненности движения и перемещения твердых частиц относительно
несущего горизонтального потока.
Приведена методика расчета и выбора параметров классификаторов, информация об
опыте проектирования и внедрения горизонтальных классификаторов в составе добычных
комплексов при освоении обводненных месторождений песков.
Монография может быть полезна студентам, инженерно-техническим работникам,
сотрудникам высших учебных заведений, научно-исследовательских институтов и
проектных организаций горной промышленности
An international multi-center investigation on the accuracy of radionuclide calibrators in nuclear medicine theragnostics
Background: Personalized molecular radiotherapy based on theragnostics requires accurate quantification of the amount of radiopharmaceutical activity administered to patients both in diagnostic and therapeutic applications. This international multi-center study aims to investigate the clinical measurement accuracy of radionuclide calibrators for 7 radionuclides used in theragnostics: 99mTc, 111In, 123I, 124I, 131I, 177Lu, and 90Y. Methods: In total, 32 radionuclide calibrators from 8 hospitals located in the Netherlands, Belgium, and Germany were tested. For each radio
Manifestação clínico-patológica de infecção natural pelo Vírus Respiratório Sincicial Bovino (BRSV) em bovinos de criação extensiva no Rio Grande do Sul, Brasil
A novel BACE inhibitor NB-360 shows a superior pharmacological profile and robust reduction of amyloid-β and neuroinflammation in APP transgenic mice
Mechanisms of Formation and Destruction of Polychlorinated Dibenzo-p-dioxins and Dibenzofurans in Heterogeneous Systems
Experimental Evaluation of the Impact of Intrinsic Process Parameters on the Performance of a Continuous Chromatographic Polishing Unit (MCSGP)
Design space and robustness analysis of batch and counter-current frontal chromatography processes for the removal of antibody aggregates
Increasing molecular diversity and market competition requires biopharmaceutical manufacturers to intensify their processes. In this respect, frontal chromatography on cation exchange resins has shown its potential to effectively remove aggregates. However, yield losses during the wash step need to be accepted in order to ensure robust product quality. In this work, we present a novel counter-current frontal chromatography process called Flow2, which uses inline dilution during an interconnected wash phase to allow high monomer recovery without contaminating the product pool with impurities. Its model-based design spaces under purity and yield constraints are compared with those corresponding to traditional batch processes in terms of size and process attributes yield and productivity. The Flow2 process shows the largest extent of feasible operating points independent of feed conditions. Thereby, it allows the implementation of higher ionic strength wash, thus widening the range of operating conditions resulting in yields above 95% compared to batch processes. Productivities of batch and counter-current processes are the same at short regeneration times and equal residence time. However, long regeneration times, while influencing the size of the Flow2 design space, are not detrimental for its productivity resulting in twice as high values as obtained for the batch process. Furthermore, process robustness is evaluated by the ability of the process to maintain the required product quality when subjected to process parameter perturbations. It is found that the Flow2 process is able to retain a larger design space associated also with higher yields showing its ability to improve process attributes without sacrificing robustness at the same time
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