75 research outputs found
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Electrodeposited metal-organic framework films as self-assembled hierarchically superstructured supports for stable omniphobic surface coatings
Superhierarchically rough films are rapidly synthesised on metal substrates via electrochemically triggered self-assembly of meso/macroporous-structured metal-organic framework (MOF) crystals. These coatings are applied to immobilise a functional oil with low surface energy to provide stable coatings repellent to a wide range of hydrophobic as well as hydrophilic fluids. Such omniphobic surfaces are highly interesting for several applications such as anti-fouling, anti-icing, and dropwise condensation, and become easily scalable with the presented bottom-up fabrication approach. As investigated by environmental scanning electron microscopy (ESEM), the presented perfluorinated oil-infused Cu-BTC coating constitutes of a flat liquid-covered surface with protruding edges of octahedral superstructured MOF crystals. Water and non-polar diiodomethane droplets form considerably high contact angles and even low-surface-tension fluids, e.g. acetone, form droplets on the infused coating. The repellent properties towards the test fluids do not change upon extended water spraying in contrast to oil-infused porous copper oxide or native copper surfaces. It is discussed in detail, how the presented electrodeposited MOF films grow and provide a proficient surface morphology to stabilise the functional oil film due to hemiwicking
Characterizing Inorganic Scintillation Detectors for Determining Radiation Exposure -11358
ABSTRACT A number of buildings at Oak Ridge National Lab (ORNL) and Y-12 National Security Complex have been slated for deactivation and decommissioning (D&D) under the Integrated Facility Disposition Project (IFDP). Virtually all of these buildings were used for developing nuclear and radiochemical technologies. The buildings slated for D&D may be contaminated with unknown quantities of radioactive materials. A survey to determine the location of radioactive material and the extent of contamination needs to be performed in each building before personnel can safely enter the buildings and begin D&D. This paper describes the method and equipment used to correlate gamma ray spectra to dosimetric data and methods employed in identifying the gamma detectors that are most effective for dosimetric conversion. The absolute efficiency of several NaI(Tl) and LaBr 3 (Ce) detectors have been measured as a function of distance from several high-activity radioactive isotopes. Systematic surveys of contaminated sites can locate and identify contaminating isotopes. If the source is identified and the position is known, an absolute efficiency value can be matched to the source, allowing for the activity to be easily calculated. If the activity of the source has been determined, using methods described by the National Council on Radiation Protection and Measurements, the dose to personnel as a function of distance from a source can be determined
Research on the thermal decomposition of Mongolian Baganuur lignite and Naryn sukhait bituminous coal
The technical characteristics, elemental composition of the organic and mineral matters, ash melting behaviors and carbonization and gasification reactivities of coals from Baganuur and Naryn sukhait deposits were investigated. The results of proximate and ultimate analysis confirmed that the coal from Baganuur deposit can be graded as a low rank lignite B2 mark coal and Naryn sukhait coal is a bituminous G mark one. The carbonization and gasification experiments were performed using TGA apparatus and fixed bed quartz reactor. The data obtained with two experimental reactors showed that Baganuur lignite had lower thermal stability and much higher CO2 gasification reactivity at 950°C as compared to those for Naryn sukhait bituminous coal.Mongolian Journal of Chemistry 16 (42), 2015, 22-2
Low spin spectroscopy of neutron-rich 43,44,45Cl via {\beta} and (\beta}n decay
{\beta} decay of neutron-rich isotopes 43,45 S,studied at the National
Superconducting Cyclotron Laboratory is reported here. {\beta} delayed {\gamma}
transitions were detected by an array of 16 clover detectors surrounding the
Beta Counting Station which consists of a 40x40 Double Sided Silicon Strip
Detector followed by a Single Sided Silicon Strip Detector. {\beta} decay
half-lives have been extracted for 43,45 S by correlating implants and decays
in the pixelated implant detector with further coincidence with {\gamma}
transitions in the daughter nucleus. The level structure of 43,45 Cl is
expanded by the addition of 20 new {\gamma} transitions in 43Cl and 8 in 45 Cl
with the observation of core excited negative-parity states for the first time.
For 45 S decay, a large fraction of the {\beta} decay strength goes to delayed
neutron emission populating states in 44 Cl which are also presented.
Comparison of experimental observations is made to detailed shell-model
calculations using the SDPFSDG-MU interaction to highlight the role of the
diminished N = 28 neutron shell gap and the near degeneracy of the proton s 1/2
and d 3/2 orbitals on the structure of the neutron-rich Cl isotopes. The
current work also provides further support to a ground state spin-parity
assignment of 3/2 + in 45 Cl
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