Nanotube Potential Future in Nuclear Power

2008 ◽  
Vol 1081 ◽  
Author(s):  
Liviu Popa-Simil
Keyword(s):  
Carbon Nanotubes ◽  
Composite Structures ◽  
Nuclear Power ◽  
Nuclear Reactor ◽  
High Efficiency ◽  
Gamma Ray ◽  
Direct Conversion ◽  
Nuclear Radiation ◽  
X Rays ◽  
Theoretical Approaches

AbstractThe nanotubes presents high potential of applications in nuclear power, integrating them both in advanced fuels developments nano-breeding and in nano-shielding. The carbon nanotubes may be successfully used to create fuel wires used in high temperature applications and near perfect burning generating new procedures in nuclear reactor waste management while reducing the waste by two orders of magnitude. The modified nanowire may hold various other materials as conductors and insulators being useful in direct conversion of the nuclear energy into electricity, by including in the center a sequence of high and low electron density conductors. As direct conversion structures they can handle all the required functions into a nuclear reactor or energy harvesting blanket to assure high power density, high efficiency and minimal waste. Another very challenging application is the usage of nanotube to channel low energy nuclear radiation and guide it, similar to the GHz wave-guides or to hundreds of THz optic fibers. The operation domain of the nanotubes is placed mainly in the domain of UV to X rays, being the role of composite structures or nanowire channeling to cover the gamma ray domain. The carbon nanotubes may become useful cold neutrons transport devices with directive capabilities as short bending or focusing. The theoretical approaches and simulations predicted these new application capabilities of nanowires for nuclear materials with exceptional properties.

Pseudo-Capacitor Structure for Direct Nuclear Energy Conversion

2008 ◽  
Vol 1100 ◽  
Author(s):  
Liviu Popa-Simil
Keyword(s):  
Energy Conversion ◽  
Nuclear Power ◽  
Nuclear Energy ◽  
Nuclear Reactor ◽  
High Efficiency ◽  
Nuclear Reactors ◽  
Direct Conversion ◽  
Space Applications ◽  
Power Sources ◽  
Conversion Efficiencies

AbstractThe advanced space missions need for more power opened the way for advanced nuclear reactors and for alternative power conversion procedures. The most advanced power systems available in space are the fuel cells and nuclear reactors. Both systems manifest low efficiencies for converting the primary energy into electricity and as consequence are requiring high heat dump into space mainly by infrared radiation. The thermo-nuclear power generator also requires a high temperature gas turbine and a mechano-electric generator, finally driving to low conversion efficiencies. The new nano-materials offer the possibility of creating direct energy conversion devices able of achieving high conversion efficiencies up to 99% in the cryogenic versions. The interest for direct conversion of the nuclear energy into electricity appeared in early 1940th, by the invention of the thermo-ionic fission device by Linder. Then a series of patents and scientific papers improved gradually the designs and performances of the devices, up to the actual concepts of beta-voltaic and liquid-electronics. The most intuitive direct conversion device looks mainly like a super mirror- or a heterogeneous super-capacitor. The issues on its operation are related to global conversion efficiencies and the stable operation life-time in high radiation field. There are combinations of nano-structures and actinides assuring both the neutron flux stability, by meeting criticality conditions and the direct conversion or the nuclear energy into electricity. Achieving a high efficiency internal conversion of the nuclear energy into electricity is not enough if it is not completed by a high efficiency power extraction system from the nuclear reactor core into the outside load. The development of the new MEMS devices and micro electronics in the 40 nm technologies provides an excellent background for the production of the electric power harvesting and conversion devices embedded in the fuel. The new nano-structured materials may be produced as radiation energy harvesting tiles that are free of actinides, using them for harvesting the energy of radioactive sources and controlled fusion devices, or may include actinides in their structure achieving critical or sub-critical accelerator driven nuclear reactor assemblies. Another predictable advantage of the nano-structure is the property of self-repairing and self-organizing to compensate the radiation damage and improve the lifetime. Due to direct conversion the power density of the new materials may increase from the actual average of 0.2 kw/cm3 to about 1 kw/mm3 driving to miniaturization of nuclear power sources and reductions of the shield weight. At these dimensions and power densities of few thousands horse power per liter the nuclear power source becomes suitable for mobile applications as powering trains, strategic airplanes, etc. These new developments may drive to the production of high power solid-state compact nuclear battery for space applications, leading to a new development stage.

Risk Reporting in the Chinese News Media in Response to Radiation Threat From the Fukushima Nuclear Reactor Crisis

2013 ◽  
Author(s):  
Wen Wang
Keyword(s):  
News Media ◽  
Nuclear Power ◽  
Nuclear Reactor ◽  
Nuclear Radiation ◽  
Sources Of Information ◽  
Media Report ◽  
News Reports ◽  
The Media ◽  
The Government ◽  
Risk Reporting

On March 11, 2011, the northeastern coast of Japan was struck by 9.0-magnitude earthquake that triggered a devastating tsunami. Aside from the huge toll in people’s lives and severe damages to property, the tremor sent the Fukushima Daiichi Nuclear Power Plant on a tailspin, causing hydrogen explosions in three reactors, and sending radioactive materials into the air and bodies of water. Declared the largest nuclear disaster since Chernobyl, the crisis threatened neighboring countries, including China (International Business Times, 2011). On March 28, low levels of iodine-131, cesium-137 and strontium, believed to have drifted from Japan, were detected in the air over Heilongjiang province in the northeast part of China and in seawater samples collected in the eastern coastal areas (Qianjiang Eve News, 2011). Because these chemicals can enter the food chain and adversely affect human health (Ifeng.com, 2011), people became understandably anxious and the government had to avert panic. This study asks: How did the Chinese media report the risks attendant to this event? A content analysis of 45 straight news reports published by the Chinese press from March 16, 2011 to April 25, 2011 was conducted. The analysis focused on how the media explained the risk, portrayed potential harm, reported on government actions to safeguard public health, and provided suggestions to reduce public fear. The sources of information cited in the reports were also identified. The articles examined were collected from People.com, a comprehensive online archive of news reports, using “Fukushima” and “nuclear radiation” as search terms. The results indicated journalistic practices that left much to be desired in terms of risk reporting. First, the articles explained little about the technical aspects of the radiation leaks and failed to give audiences a general indication of levels of risk. Second, the media over-emphasized the government’s position that the environment was safe despite the more rampant word-of-mouth reports to the contrary, a slant that may have done nothing to allay public fear. Third, there was a dearth of information about what the government intends to do to alleviate the situation and suggestions about what people can do to protect themselves. The themes of news reports may be attributed to experts from research institutions and government officials who were the most frequently cited sources of facts, analyses, interpretations, and opinions. Scientists and nuclear experts were cited the most in the news reports.

Research on Chinese Public Mental in Post-Fukushima Era

2013 ◽  
Author(s):  
Li Min
Keyword(s):  
Nuclear Power ◽  
Large Scale ◽  
High Efficiency ◽  
Nuclear Accident ◽  
Basic Knowledge ◽  
Nuclear Radiation ◽  
The Public ◽  
Nuclear Power Development ◽  
External Causes ◽  
Countermeasures And Suggestions

Fukushima nuclear accident aroused large-scale public panic toward nuclear power development. Due to the limit knowledge of nuclear power, some people feel frightened and fearful for nuclear safety, nuclear radiation as well as nuclear accident. As the energy with clean, stable and high-efficiency, nuclear power always takes imperative and irreplaceable role in Chinese energy program. Therefore, public acceptance and basic knowledge towards nuclear power in post-Fukushima era is facing new unprecedented challenge. How to relieve the panic and frightening of the public and recover the confidence of nuclear power safety is gradually becoming the hot issue among public. This paper makes detailed investigations of current public mental in China toward nuclear power in post-Fukushima era, analyzes the internal and external causes of the panic feeling and further proposes several countermeasures and suggestions accordingly for safe and health development of nuclear power in China.

scholarly journals Nuclear safety in perspective

1983 ◽  
Vol 2 (1) ◽  
pp. 41-47
Author(s):  
J. K. Basson
Keyword(s):  
Nuclear Power ◽  
Radiation Effects ◽  
Nuclear Reactor ◽  
Health Hazard ◽  
Nuclear Safety ◽  
X Rays ◽  
Reactor Operation ◽  
Power Station ◽  
Local Conditions ◽  
Radio Isotopes

The impending operation of South Africa’s first nuclear power station, Koeberg, necessitates a thorough analysis of nuclear safety under local conditions. More is known, worldwide, about radiation effects than about any other health hazard, and international norms have already been accepted since 1928. The widespread use of X-rays and radio-isotopes, the extraction and processing of uranium, visits by nuclear-powered ships and, especially, the nuclear-reactor operation in South Africa. Consequently, the pre-operational investigations of Koeberg could be completed thoroughly, with full confidence in its safe commissioning.

scholarly journals The first ICRANet catalog of binary-driven hypernovae

2018 ◽  
Vol 168 ◽  
pp. 04002
Author(s):  
G. B. Pisani ◽  
R. Ruffini ◽  
Y. Aimuratov ◽  
C. L. Bianco ◽  
M. Karlica ◽  
...  
Keyword(s):  
Rest Frame ◽  
Gamma Ray ◽  
Late Time ◽  
X Rays ◽  
Striking Result ◽  
Theoretical Approaches ◽  
Power Law Decay ◽  
Long Duration ◽  
Comprehensive Picture ◽  
Distance Indicator

In a series of recent publications, scientists from ICRANet, led by professor Remo Ruffini, have reached a novel comprehensive picture of gamma-ray bursts (GRBs) thanks to their development of a series of new theoretical approaches. Among those, the induced gravitational collapse (IGC) paradigm explains a class of energetic, long-duration GRBs associated with Ib/c supernovae (SN), recently named binary-driven hypernovae (BdHNe). BdHNe have a well defined set of observational features which allow to identify them. Among them, the main two are: 1) long duration of the GRB explosion, namely larger than 2 s in the rest frame; 2) a total energy, released in all directions by the GRB explosion, larger than 1052 ergs. A striking result is the observation, in the BdHNe sources, of a universal late time power-law decay in the X-rays luminosity after 104 s, with typical decaying slope of ~ 1.5. This leads to the possible establishment of a new distance indicator having redshift up to z ~ 8. Thanks to this novel theoretical and observational understanding, it was possible for ICRANet scientists to build the firstst BdHNe catalog, composed by the 345 BdHNe identified up to the end of 2016.

Eds Of Radioactive Particles By Self-Induced Fluorescence

1990 ◽  
Vol 48 (2) ◽  
pp. 238-239
Author(s):  
Gregory L. Finch ◽  
Richard G. Cuddihy
Keyword(s):  
Electron Beam Irradiation ◽  
Nuclear Reactor ◽  
X Rays ◽  
Reactor Accident ◽  
Internal Radiation ◽  
X Ray ◽  
External Sources ◽  
X Irradiation ◽  
Available Information ◽  
Individual Particles

The elemental composition of individual particles is commonly measured by using energydispersive spectroscopic microanalysis (EDS) of samples excited with electron beam irradiation. Similarly, several investigators have characterized particles by using external monochromatic X-irradiation rather than electrons. However, there is little available information describing measurements of particulate characteristic X rays produced not from external sources of radiation, but rather from internal radiation contained within the particle itself. Here, we describe the low-energy (< 20 KeV) characteristic X-ray spectra produced by internal radiation self-excitation of two general types of particulate samples; individual radioactive particles produced during the Chernobyl nuclear reactor accident and radioactive fused aluminosilicate particles (FAP). In addition, we compare these spectra with those generated by conventional EDS.Approximately thirty radioactive particle samples from the Chernobyl accident were on a sample of wood that was near the reactor when the accident occurred. Individual particles still on the wood were microdissected from the bulk matrix after bulk autoradiography.

scholarly journals High-Efficiency Responsive Smart Windows Fabricated by Carbon Nanotubes Modified by Liquid Crystalline Polymers

Crystals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 440
Author(s):  
Yuan Deng ◽  
Shi-Qin Li ◽  
Qian Yang ◽  
Zhi-Wang Luo ◽  
He-Lou Xie
Keyword(s):  
Carbon Nanotubes ◽  
Liquid Crystalline ◽  
Near Infrared ◽  
High Efficiency ◽  
Polymer Brush ◽  
Light Transmittance ◽  
Smart Window ◽  
Vertical Orientation ◽  
Smart Windows ◽  
Conversion Materials

Smart windows can dynamically and adaptively adjust the light transmittance in non-energy or low-energy ways to maintain a comfortable ambient temperature, which are conducive to efficient use of energy. This work proposes a liquid crystal (LC) smart window with highly efficient near-infrared (NIR) response using carbon nanotubes grafted by biphenyl LC polymer brush (CNT-PDB) as the orientation layer. The resultant CNT-PDB polymer brush can provide the vertical orientation of LC molecules to maintain the initial transparency. At the same time, the smart window shows a rapid response to NIR light, which can quickly adjust the light transmittance to prevent sunlight from entering the room. Different from common doping systems, this method avoids the problem of poor compatibility between the LC host and photothermal conversion materials, which is beneficial for improving the durability of the device.

scholarly journals Gamma-ray astrophysics in the MeV range

2021 ◽  
Author(s):  
Alessandro De Angelis ◽  
Vincent Tatischeff ◽  
Andrea Argan ◽  
Søren Brandt ◽  
Andrea Bulgarelli ◽  
...  
Keyword(s):  
High Efficiency ◽  
Gamma Ray ◽  
Earth Science ◽  
Technological Development ◽  
Cosmic Ray ◽  
Space Mission ◽  
Compact Objects ◽  
Medium Size ◽  
Cosmic Ray Interactions ◽  
Silicon Microstrip Detectors

AbstractThe energy range between about 100 keV and 1 GeV is of interest for a vast class of astrophysical topics. In particular, (1) it is the missing ingredient for understanding extreme processes in the multi-messenger era; (2) it allows localizing cosmic-ray interactions with background material and radiation in the Universe, and spotting the reprocessing of these particles; (3) last but not least, gamma-ray emission lines trace the formation of elements in the Galaxy and beyond. In addition, studying the still largely unexplored MeV domain of astronomy would provide for a rich observatory science, including the study of compact objects, solar- and Earth-science, as well as fundamental physics. The technological development of silicon microstrip detectors makes it possible now to detect MeV photons in space with high efficiency and low background. During the last decade, a concept of detector (“ASTROGAM”) has been proposed to fulfil these goals, based on a silicon hodoscope, a 3D position-sensitive calorimeter, and an anticoincidence detector. In this paper we stress the importance of a medium size (M-class) space mission, dubbed “ASTROMEV”, to fulfil these objectives.

scholarly journals Introducing the HD+B model for pulsar wind nebulae: a hybrid hydrodynamics/radiative approach

2020 ◽  
Vol 494 (3) ◽  
pp. 4357-4370
Author(s):  
B Olmi ◽  
D F Torres
Keyword(s):  
Gamma Ray ◽  
High Energy ◽  
Theoretical Modelling ◽  
X Rays ◽  
Pulsar Wind Nebulae ◽  
New Approach ◽  
Energy Gamma ◽  
Radiative Model ◽  
Pulsar Wind

ABSTRACT Identification and characterization of a rapidly increasing number of pulsar wind nebulae is, and will continue to be, a challenge of high-energy gamma-ray astrophysics. Given that such systems constitute -by far- the most numerous expected population in the TeV regime, such characterization is important not only to learn about the sources per se from an individual and population perspective, but also to be able to connect them with observations at other frequencies, especially in radio and X-rays. Also, we need to remove the emission from nebulae in highly confused regions of the sky for revealing other underlying emitters. In this paper, we present a new approach for theoretical modelling of pulsar wind nebulae: a hybrid hydrodynamic-radiative model able to reproduce morphological features and spectra of the sources, with relatively limited numerical cost.

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