| 1. |
|
|
| 2. |
- Chung, S., et al.
(författare)
-
Investigation of Magnetic Properties in Co/Ni -NiFe Exchange Spring Magnet
- 2021
-
Ingår i: Journal of the Korean Magnetics Society. - : The Korean Magnetics Society. - 1598-5385 .- 2233-6648. ; 31:1, s. 34-38
-
Tidskriftsartikel (refereegranskat)abstract
- We investigate the magnetic proprieties of [Co/Ni]-NiFe exchange spring magnets having 1) different thick NiFe layers, 2) two different stack sequences, and 3) different thick Cu spacer between [Co/Ni] multilayers and NiFe layer. We show that the magnetization tilt angle can be tuned from out-of-plane (OOP) to in-plane (IP) by varying the NiFe thickness (t(NiFe)) larger than t(NiFe) = 1.5 nm, while similar transition occurs from thinner t(NiFe) when NiFe layer was deposited earlier than [Co/Ni] multilayers. Finally, we insert Cu spacer between [Co/Ni] multilayers and NiFe layer to figure out how strongly these are coupled. We find the rapid decoupling behavior as a increase of Cu spacer thickness (t(Cu)) between 0.5 and 1.3 nm.
|
|
| 3. |
- Ha, S., et al.
(författare)
-
Transmission of low-energy Cl- ions through Al2O3 insulating nanocapillaries
- 2020
-
Ingår i: Acta Physica Sinica. - : Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences. - 1000-3290. ; 69:9
-
Tidskriftsartikel (refereegranskat)abstract
- The transmission of 10-keV Cl- ions through Al2O3 insulating nanocapillaries is studied both by experiment and simulation. The double-peak structure in the transmitted angular distribution is found to be the same as our previous result. The peak around the direction of the primary beam is caused mainly by the directly transmitted Cl-, and the other peak around the tilt angle of Al2O3 nanocapillaries is mainly induced by Cl+ and Cl-0. The intensity of transmitted Cl- decreases with the tilt angle increasing, which is in accord with the geometrically allowed transmission. Beyond the geometrically allowed angle, the transmitted projectiles are mainly Cl+ ions and Cl-0 atoms. The ratio of transmitted Cl+ ion to Cl-0 atom drops as tilt angle increases, and it turns more obvious when the tilt angle is larger than the limit of the geometrical transmission. A detailed physics process was developed within Geometry and Tracking 4 (Geant4) to perform the trajectory simulation, in which the forces from the deposited charges and the image charges, the scattering from the surfaces as well as the charge exchange are taken into consideration. The transmissions at the tilt angle of 1.6 degrees are simulated for the cases without and with deposited charges of -100 e/capillary. For the deposition charge quantity of -100 e/capillary, the majority of the transmitted projectiles are mainly the directly transmitted Cl- ions exiting to the direction of tilt angle, and the transmitted Cl-0 and Cl+ account for a very small portion. While for the case with no deposited charges, the simulation results agree well with the experimental results. The dependence of the scattering process on the tilt angle, which results in the different features in the transmitted projectiles, is studied in detail by the simulation. It is found that the transmitted Cl-0 atoms exit through single to multiple scattering, and most of transmitted Cl-0 atoms exit through single and double scattering, and are centered along the axis of nanocapillaries, while Cl+ ions mainly exit by single scattering, which results in the fact that the intensity of the transmitted Cl-0 atoms drops slower than that of the transmitted Cl+ ions with the increase of the tilt angle, leading the ratio of the transmitted Cl+ to Cl-0 to decrease as the tilt angle increases in experiment. Our results describe the physical mechanism of low-energy ions through insulating nanocapillaries in detail, i.e. how the scattering process dominates the final transmission. It is found that the transmission of the negative ions in the energy range above 10 keV is caused by the scattering and the charge exchange process.
|
|
| 4. |
- Posch, Josefina
(författare)
-
[Prussian] BLUESHIFT – Space Debris 2551
- 2022
-
Ingår i: Stora Alvaret, Öland, Sweden, The Swedish Sculptors´ Association, 2022-06-11.
-
Konstnärligt arbete (övrigt vetenskapligt/konstnärligt)abstract
- The sculpture [Prussian] BLUESHIFT - Space Debris 2551 takes its shape from the satellite Cosmos 2551. One of the biggest fragmentation events in space took place in 2009 when the abandoned satellite Cosmos 2251 and Iridium 33 collided, leading to the destruction of both satellites. To this day, over 1000 catalogued space debris objects from the collision circulate around the Earth and one of the orbits passes right over Öland. When an object in space moves towards us, the light from the object is called blueshift, which describes the change in the frequency of a light wave. The color of the sculpture is Prussian blue, which is on the World Health Organisation's list of essential medicines and is used as an antidote to certain heavy metals and radioactivity. The artistic research work questions ownership and responsibility for the pollution caused by colonisation and space tourism. Led by wealthy nations and private companies, this reflects the colonisation of the Earth whose negative impact on the environment and cultures we have yet to come to terms with. The sculpture is mostly created from recycled material from discarded student projects from the HDK-Valand art school and the Gothenburg Opera's metal textiles set design from the climate-smart production of The Ring of the Nibelung.
|
|
| 5. |
- Posch, Josefina
(författare)
-
”Sipping Cosmic Latte in the Milky Way, waiting for The Big Crunch” and ”We are taking great pains to make sure there’s not an orbital debris issue”
- 2022
-
Ingår i: Rovaniemi Finland, Arktikum Science Centre and Museum, 2022-12-02.
-
Konstnärligt arbete (övrigt vetenskapligt/konstnärligt)abstract
- The two sculptures in the exhibition encompasses, discarded materials from the Arktikum Science Centre, the HDK-Valand Academy of Art and Design workshops and the Gothenburg Opera. The sculpture ”We are taking great pains to make sure there’s not an orbital debris issue” includes images from her collaborations with the artificial intelligence bot Midjourney, based upon the Elon Musk statement which is also the title of the work [1] regarding the SpaceX expansion. In my artistic research practice I explore questions of ownership and responsibility for the (light) pollution caused by colonization, space tourism and commercial space tech companies. Led by wealthy nations and private companies, this reflects the colonization of the Earth whose negative impact on the environment and cultures we have yet to come to terms with. It is estimated that there is already more than 200 000 kg of artificial material on the Moon, and the number of large pieces of debris in space is about 20 000. The starry sky we look upon nowadays is actually scattered with artificial lights which impossible for the bare eye to tell the difference. The sculpture ”Sipping Cosmic Latte in the Milky Way, waiting for The Big Crunch” is a reference to the color of the Universe as defined by scientists Karl Glazebrook and Ivan Baldry, named Cosmic Latte for its creamy yellowish white hue. The Big Crunch is a hypothetical scenario for the ultimate fate of the universe, in which the expansion of the universe eventually reverses and the universe recollapses. [3] [1] https://www.theatlantic.com/science/archive/2019/05/spacex-satellites-starlink/590269 [2]https://www.astro.ljmu.ac.uk/~ikb/Cosmic-Spectrum.html [3]https://www.encyclopedia.com/education/encyclopedias-almanacs-transcripts-and-maps/big-crunch-theory
|
|
| 6. |
|
|
| 7. |
|
|
