Results 51 to 60 of about 49,381 (294)

Novas tecnologias, novas competências [PDF]

Educar em Revista, 2008
O texto aborda a relação dos jovens e adolescentes com tecnologias, nem "novas" nem "velhas", e sim instrumentos para informar e comunicar, divertir, auxiliar nos trabalhos escolares. Apesar de reconhecer a familiaridade dessa geração com o que há de mais avançado em termos de tecnologia, aponta a necessidade de se compreender a complexidade desse novo
openaire   +2 more sources

Multipurpose Transparent Nanocomposites for Gamma Spectroscopy, Pulse Shape Discrimination, Thermal Neutron Detection, Radiation Shielding, and High Refractive Index Applications

Advanced Functional Materials, EarlyView.
Materials exist that are useful for gamma scintillation, radiation shielding, neutron‐gamma pulse shape discrimination (PSD), thermal neutron detection, or high refractive index applications. While certain materials have exhibited optimal performance for each of these applications, none achieve multiple functions.
Isabelle Winardi, Stephane Miaule, Robert Carmichael, Bowen Sun, Ziqing Han, Prabhav Surabhi, Zhen Luo, Noelan Hum, David Prout, Yi‐An Chen, Ting‐Hsuan Wu, Hao Yu, Arion Chatziioannou, Qibing Pei   +13 more
wiley   +1 more source

An Extremely Massive White Dwarf of the Symbiotic Classical Nova V407 Cyg as Suggested by the RS Oph and U SCO Models

Open Astronomy, 2012
We have analyzed the optical light curve of the symbiotic star V407 Cyg that underwent a classical nova outburst in 2010 March. Being guided by a supersoft X-ray phase observed during days 20-40 after the nova outburst, we are able to reproduce the light
Hachisu I., Kato M.
doaj   +1 more source

Shortest Recurrence Periods of Forced Novae

, 2016
We revisit hydrogen shell burning on white dwarfs (WDs) with higher mass accretion rates than the stability limit, \dot M_stable, above which hydrogen burning is stable. Novae occur with mass accretion rates below the limit.
Hachisu, Izumi, Kato, Mariko, Saio, Hideyuki   +2 more
core   +1 more source

Pixelation‐Free, Monolithic Iontronic Pressure Sensors Enabling Large‐Area Simultaneous Pressure and Position Recognition via Machine Learning

Advanced Functional Materials, EarlyView.
A pixelation‐free, monolithic iontronic pressure sensor enables simultaneous pressure and position sensing over large areas. AC‐driven ion release generates spatially varying impedance pathways depending on the pressure. Machine learning algorithms effectively decouple overlapping pressure–position signals from the multichannel outputs, achieving high ...
Juhui Kim, Junseo Lee, Kwang‐Hun Choi, Seongil Im, Jae Hong Kim, Changsoon Choi, Junghwan Byun, Changhwan Shin, Ho Won Jang, Hyunsu Ju, Jung Ah Lim   +10 more
wiley   +1 more source

The Newly Discovered Nova Super-remnant Surrounding Recurrent Nova T Coronae Borealis: Will it Light Up during the Coming Eruption?

The Astrophysical Journal Letters
A century or less separates the thermonuclear-powered eruptions of recurrent novae (RNe) in the hydrogen-rich envelopes of massive white dwarfs. The colliding ejecta of successive RN events are predicted to always generate very large (tens of parsecs ...
Michael M. Shara, Kenneth M. Lanzetta, Alexandra Masegian, James T. Garland, Stefan Gromoll, Joanna Mikolajewska, Mikita Misiura, David Valls-Gabaud, Frederick M. Walter, John K. Webb   +9 more
doaj   +1 more source

Nucleation‐Controlled Reconstruction of CuOx for Selective CO2 Electroreduction

Advanced Functional Materials, EarlyView.
The ratio of oxygen vacancies (Ov) and exposed Cu2O (111)/(200) of CuOx precatalyst is modulated by nucleation control of Cu(OH)2 precursor. Low Ov ratio and high ratio of Cu2O (111)/(200) in slow‐nucleated CuOx reconstructs to high‐coordinated oxide‐derived copper (OD‐Cu) during electrochemical CO2 reduction reaction (CO2RR) and exhibits enhanced ...
Ying Ying Ch'ng, Zhipeng Ma, Ming Zhang, Shujie Zhou, Varun Kundi, Priyank Vijaya Kumar, Wenyu Zhong, Yuwei Yang, Jitraporn Vongsvivut, Qinfen Gu, Xiaoxuan Luo, Lixue Jiang, Rahman Daiyan, Zhaojun Han, Rose Amal   +14 more
wiley   +1 more source

Helium-deficient ER UMa-type Dwarf Nova below the Period Minimum with a Hot Secondary

The Astrophysical Journal
We present the discovery of a peculiar dwarf nova KSP-OT-201712a using high-cadence, multicolor observations made with the Korea Microlensing Telescope Network.
Youngdae Lee, Dae-Sik Moon, Sang Chul Kim, Hong Soo Park, Yuan Qi Ni   +4 more
doaj   +1 more source

Recurrent Novae, Classical Novae, Symbiotic Novae, and Population II Novae

, 2001
Light curve analysis of decay phase of nova outburst are summarized. Nova duration is determined by the strong wind mass-loss which depends only on the white dwarf mass. Fast novae correspond very massive white dwarfs and very slow novae correspond almost lower mass limit of white dwarfs.
openaire   +2 more sources

Recurrent novae [PDF]

International Astronomical Union Colloquium, 1990
AbstractThermonuclear models of recurrent novae demand white dwarf accretors near the Chandrasekhar mass. In this case, the known recurrent novae should possess classical counterparts bearing the same structural parameters and space distribution, save for having only marginally less massive white dwarfs.
openaire   +1 more source