Search results for "A2"
showing 10 items of 1101 documents
Single-Event Burnout Mechanisms in SiC Power MOSFETs
2018
Heavy ion-induced single-event burnout (SEB) is investigated in high-voltage silicon carbide power MOSFETs. Experimental data for 1200-V SiC power MOSFETs show a significant decrease in SEB onset voltage for particle linear energy transfers greater than 10 MeV/cm 2 /mg, above which the SEB threshold voltage is nearly constant at half of the rated maximum operating voltage for these devices. TCAD simulations show a parasitic bipolar junction transistor turn-on mechanism, which drives the avalanching of carriers and leads to runaway drain current, resulting in SEB. peerReviewed
Characterization of a neutron-beta counting system with beta-delayed neutron emitters
2016
Abstract A new detection system for the measurement of beta-delayed neutron emission probabilities has been characterized using fission products with well known β-delayed neutron emission properties. The setup consists of BELEN-20, a 4π neutron counter with twenty 3He proportional tubes arranged inside a large polyethylene neutron moderator, a thin Si detector for β counting and a self-triggering digital data acquisition system. The use of delayed-neutron precursors with different neutron emission windows allowed the study of the effect of energy dependency on neutron, β and β–neutron rates. The observed effect is well reproduced by Monte Carlo simulations. The impact of this dependency on …
SEE on Different Layers of Stacked-SRAMs
2015
International audience; This paper presents heavy-ion and proton radiation test results of a 90 nm COTS SRAM with stacked structure. Radiation tests were made using high penetration heavy-ion cocktails at the HIF (Belgium) and at RADEF (Finland) as well as low energy protons at RADEF. The heavy-ion SEU cross-section showed an unusual profile with a peak at the lowest LET (heavy-ion with the highest penetration range). The discrepancy is due to the fact that the SRAM is constituted of two vertically stacked dice. The impact of proton testing on the response of both stacked dice is presented. The results are discussed and the SEU cross-sections of the upper and lower layers are compared. The …
IGISOL control system modernization
2016
Abstract Since 2010, the IGISOL research facility at the Accelerator laboratory of the University of Jyvaskyla has gone through major changes. Comparing the new IGISOL4 facility to the former IGISOL3 setup, the size of the facility has more than doubled, the length of the ion transport line has grown to about 50 m with several measurement setups and extension capabilities, and the accelerated ions can be fed to the facility from two different cyclotrons. The facility has evolved to a system comprising hundreds of manual, pneumatic and electronic devices. These changes have prompted the need to modernize also the facility control system taking care of monitoring and transporting the ion beam…
High voltage conditioning of the electrostatic deflector of MARA
2016
Abstract MARA is a new recoil mass separator in the Accelerator Laboratory of University of Jyvaskyla (JYFL-ACCLAB) with a mass resolving power of 250 and an ion-optical configuration of QQQD E D M . In this paper the construction, control and conditioning of its electrostatic deflector are described. The deflector was designed for voltages up to 500 kV accross the gap, corresponding to a 3.6 MV/m field, to accomodate fusion reactions with inverse kinematics. Titanium electrodes with a beam dump opening in the anode are used. The conditioning procedure, which has been used repeatedly to take the deflector to 450 kV, is described, along with the safety systems and precautions that are in pla…
Study of Proton and 3He Induced Reactions on 235U at Low Energies
2014
Abstract Highly enriched 235 U targets were irradiated with 6.5 − 16.1 MeV protons and 20.4 − 42.0 MeV 3 He ions. The irradiated targets were measured with γ and α spectrometric methods to identify and quantify the produced reaction products. After primary activity measurements the targets were dissolved, and interesting Pu and Np reaction products were chemically separated from the target material, and measured for activity again. From the activity results it was possible to calculate the reaction cross sections for differently produced nuclides. The data obtained from the experiment resulted in earlier unknown excitation functions on proton and 3 He induced nuclear reactions on 235 U.
Modulation of biotransformation and elimination systems by BM-21, an aqueous ethanolic extract from Thalassia testudinum, and thalassiolin B on human…
2012
Abstract BM-21 is an extract obtained from Thalassia testudinum marine plant with pharmacological properties. The effects of BM-21 and thalassiolin B (TB), its main component, on enzyme and transport proteins involved in drug metabolism and excretion in human cultured hepatocytes were evaluated. Cells were exposed for 48 h to sub-cytotoxic concentrations of BM-21 or TB. Effects on P450 isoforms revealed significant reductions of CYP1A2, 3A4 and 2D6 activities (up to 56%, 66% and 44% inhibition, respectively) after exposition to BM-21, no changes on CYP2A6 and 2C9 activities. TB produced a concentration-dependent reduction of all P450 activities. In addition, a decrease in total UGT and UGT2…
Classification and retrieval on macroinvertebrate image databases
2011
Aquatic ecosystems are continuously threatened by a growing number of human induced changes. Macroinvertebrate biomonitoring is particularly efficient in pinpointing the cause-effect structure between slow and subtle changes and their detrimental consequences in aquatic ecosystems. The greatest obstacle to implementing efficient biomonitoring is currently the cost-intensive human expert taxonomic identification of samples. While there is evidence that automated recognition techniques can match human taxa identification accuracy at greatly reduced costs, so far the development of automated identification techniques for aquatic organisms has been minimal. In this paper, we focus on advancing …
Saistvielu ietekme uz nātrija jonu bateriju katodmateriāla Na2/3MnO2 elektrodu virsmu un elektroķīmiskajām īpašībām
2022
Saistvielu ietekme uz nātrija jonu bateriju katodmateriāla Na2/3MnO2 elektrodu virsmu un elektroķīmiskajām īpašībām Krūze B., darba vadītājs Dr.phys. Kučinskis G. Maģistra darbs. 50 lappuses, 30 attēli, 1 tabula, 26 literatūras avoti, 2 pielikumi. Latviešu valodā. Maģistra darba ietvaros sintezēts Na2/3MnO2, no kura pagatavoti 3 veidu elektrodi, izmantojot dažādas saistvielas – polivinilidēnfluorīdu, nātrija alginātu un tetrabutilamonija alginātu. Elektrodiem tika analizētas elektroķīmiskās īpašības. Augstākā lādiņietilpība (164 mAh/g) un labākā ātrumspēja sasniegta ar tetrabutilamonija alginātu pagatavotiem elektrodiem, taču ciklējamība – ar nātrija alginātu. Pagatavotajiem elektrodiem tik…
Genetic predisposition to male breast cancer in Poland
2021
Abstract Background Breast cancer in men accounts for fewer than 1 % of all breast cancer cases diagnosed in men and women. Genes which predispose to male breast cancer include BRCA1 and BRCA2. The role of other genes is less clear. In Poland, 20 founder mutations in BRCA1, BRCA2, CHEK2, PALB2, NBN, RECQL are responsible for the majority of hereditary breast cancer cases in women, but the utility this genes panel has not been tested in men. Methods We estimated the prevalence of 20 alleles in six genes (BRCA1, BRCA2, CHEK2, PALB2, NBN, RECQL) in 165 Polish male breast cancer patients. We compared the frequency of selected variants in male breast cancer cases and controls. Results One of the…