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[en] The world needs energy to support everyday life and drive human and economic development. In 2019, over 26 000 terawatt-hours of electricity were produced worldwide. This electricity is being produced by a range of energy sources, mostly fossil fuels but also nuclear power and renewables such as solar, hydro and wind. Energy production and use are the largest source of greenhouse gas emissions around the world. As greenhouse gases are a driving force behind climate change, countries worldwide are actively working on a clean energy transition by changing how energy is produced. Here’s a closer look at the clean energy transition and what role nuclear power plays.
[en] This study is concerned with the sorption behavior of natural radionuclides (226Ra, 210Po, 228Th - originated from TENORM waste associated with petroleum industry) onto silica/olive pomace nanocomposite. Initially, nanocomposites of extracted silica and olive pomace are prepared and characterized by physicochemical techniques. In the batch technique, 60% SiO2 40% olive pomace (AM3) nanocomposite showed a considerable group sorption for 226Ra and 210Po larger than 228Th in 1M HNO3 and HClO4 solutions. In case of sorption by the compacted disc, sorption of 226Ra was similar to batch method, sorption of 228Th increased slightly to ∼ 17%, while sorption of 210Po was decreased to 77%. Thus, AM3 nanocomposite can be considered as an efficient nano-adsorbent for sorption and separation of Ra-isotopes and 210Po-radionuclides from 226Ra-210Po-228Th admixture associated with nuclear and non-nuclear industries. (author)
[en] In this paper, we investigate a nonlocal SIS epidemic model with double free boundaries. The existence, uniqueness and some estimates of the global solution are discussed first. Then, with the help of studying the long-time behavior of the solution to a Cauchy problem for a nonhomogeneous heat equation, the long-time behavior of the solution to the SIS free boundary problem is obtained for the disease vanishing case. At last, some sufficient conditions for the disease vanishing are established.
[en] Nuclear power combined with smart power grids — the two-way networks that connect producers to consumers and use new technologies to do so — can help countries transition to low carbon electricity sources and ensure reliable, stable and sustainable energy supplies. Many countries are diversifying their mix of low carbon energy sources to help them decarbonize their economies and achieve their climate goals. This has led to a global shift towards renewable energy sources; however, these sources alone are not able to fully and reliably meet demand.
[en] The world is far off track when it comes to meeting the Paris Agreement climate goals of limiting the global temperature increase by 1.5°C to 2°C by 2050. Current projections show that fossil fuels will still make up the majority of world energy use by 2050. If we miss the 1.5°C target, this could mean accepting climate impacts, such as millions of people being displaced by sea level rise and millions more being exposed to extreme heatwaves, as well as major biodiversityrelated impacts, including species loss, the elimination of sea ice in the Arctic Ocean, and the loss of virtually all coral reefs. If we miss the 2°C target, half the world’s population could be exposed to summertime ‘deadly heat,’ Antarctic ice sheets could collapse, droughts could increase massively, and the Sahara Desert could begin to expand into southern Europe. World food supplies could be imperilled, driving mass human migration and leading to a growing risk of civilizational collapse. The Clean Energy Ministerial Flexible Nuclear Campaign we co-founded explores the expanded role that nuclear energy can play in de-risking the energy transition. Here, we describe two opportunities to drive deeper decarbonization with nuclear energy. The first is to expand the role of nuclear energy in electricity production through a combination of advanced reactors and thermal energy storage. This is intended to complement renewables in future energy grids. The second is to address the use of oil and gas, which currently accounts for three quarters of energy consumption, by providing large-scale, low-cost hydrogen produced with nuclear power.
[en] This paper briefly introduces the working principle, and characteristics of nuclear engineering and nuclear technology from the aspects of its application in industry, agriculture, medicine, hydrology, cultural relics, environmental protection, space exploration and cosmology, aiming to popularize the knowledge of nuclear energy and nuclear technology utilization around the public. (authors)
[en] Using high-precision nonempirical methods of modern quantum chemistry, the effect of the weak relativistic interactions on the potential energy and the permanent dipole moment of the ground electronic state of the CO molecule is studied. The relativistic energy is calculated by the following three optional methods: within the first-order perturbation theory using the Cowan–Griffin operator containing the sum of the mass-velocity and Darwin corrections, within the framework of the approximate Douglas–Kroll–Hess scalar Hamiltonian, and the most rigid “four-component” relativistic Dirac–Coulomb–Gaunt Hamiltonian. The relativistic correction obtained by different methods agrees within a few percents and equals about 55–60 cm–1 in the region of an equilibrium internuclear distance of Å. The addition of the relativistic correction decreases the equilibrium bond length by about 0.0002 Å. The magnitude of the Lamb shift estimated by the semiempirical scaling of the one-electron Darwin’s term does not exceed several inverse centimeters near . The relativistic correction to the dipole moment function is in the range from –0.001 to +0.003 D, which does not exceed 1% of the nonrelativistic component of the dipole moment.
[en] Since the 12th Five-Year Plan, China has continuously strengthened capacity building of nuclear safety supervision and management, and nuclear safety supervision and management ability gradually increases. At present, the adjustment and optimization of economic structure leads to rapid development of nuclear energy and nuclear technology utilization business, the tasks of nuclear safety supervision and management are increasingly heavy, and the requirements of nuclear safety supervision and management are more and more strict, as a result, current capabilities of supervision and management are difficult to well adapt to new age demands of supervision and management. This study firstly puts forward the connotation of capacity building of nuclear safety supervision and management, and based on the connotation brings forward the basic framework of capacity building of nuclear safety supervision and management, which is composed of institution building, agency building, equipment building and team building. Under the perspective of the basic framework, this study analyses the status quo of capacity building of national nuclear safety supervision and management, states the main ideas and directions of capacity building of nuclear safety supervision and management in the near future, and proposes some suggestions for strengthening capacity building of national nuclear safety supervision and management. (authors)
[en] With extensive use of flash-based field-programmable gate arrays (FPGAs) in military and aerospace applications, single-event effects (SEEs) of FPGAs induced by radiations have been a major concern. In this paper, we present SEE experimental study of a flash-based FPGA from Microsemi ProASIC3 product family. The relation between the cross section and different linear energy transfer (LET) values for the logic tiles and embedded RAM blocks is obtained. The results show that the sequential logic cross section depends not too much on operating frequency of the device. And the relationship between 0 → 1 upsets (zeros) and 1 → 0 upsets (ones) is different for different kinds of D-flip-flops. The devices are not sensitive to SEL up to a LET of 99.0 MeV cm2/mg. Post-beam tests show that the programming module is damaged due to the high-LET ions. (authors)
[en] The possibility of precision measurements of frequencies of forbidden transitions of cold atoms in a trap using stimulated Raman scattering is shown. Transition 1S–2S in a hydrogen atom, in which the atom passes from level 1S to level 2S via intermediate level 3P is considered in detail. In this case, the frequency of the pump field (103 nm) is close to the frequency of the 3P–1S transition, while the stimulated scattering frequency (656 nm) is close to the frequency of the 3P–2S transition.