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1.
Any increase of the energy potential is survival, independence, and prosperity of each nation (community) in the system of chaotic globalization, but the Mantra of global cooperation not always is the Mantra of a separate nation. India uses all possibilities for obtaining additional energy sources. This was demonstrated at the recent conference and exhibition “Petrotech-2009.” India assumes to increase power consumption to 400,000 MW in 2030 against 130,000 MW in 2008 at the expense of all sources. Great attention is given to renewable and alternative sources.  相似文献   

2.
徐銤 《物理》2006,35(08):689-692
20世纪三四十年代,原子物理学家们发现中子轰击铀原子核的裂变现象并首次实现可控裂变链式反应,把世界带进了原子能时代.半个世纪以来核电已达到全世界电力的16%.目前99%以上都是热中子反应堆核电站.在大规模发展核电的情况下,比如说百GWe,必须加快快中子增殖反应堆的发展和推广,方无核燃料匮乏之虞.  相似文献   

3.
徐銤 《物理》2006,35(8):689-692
20世纪三四十年代,原子物理学家们发现中子轰击铀原子核的裂变现象并首次实现可控裂变链式反应,把世界带进了原子能时代.半个世纪以来核电已达到全世界电力的16%.目前99%以上都是热中子反应堆核电站。在大规模发展核电的情况下,比如说百GWe,必须加快快中子增殖反应堆的发展和推广,方无核燃料匮乏之虞。  相似文献   

4.
Inelasticαα anddd collisions were studied at a centre-of-mass energy √S NN=31.2 GeV per nucleon-nucleon collision, using the Split-Field Magnet (SFM) detector at the CERN ISR. In this paper we show the inclusive and semi-inclusive rapidity distributions of protons, compare them with predictions of the Lund model, and calculate the average rapidity loss for participant protons. From the negative particles we calculate the inelasticity of the interaction, the average energy per particle, and the degree of isotropy of the produced hadrons.  相似文献   

5.
On the basis of the public data statistics of recent years on pollution and emissions from nuclear power plants (NPPs) and thermal power plants (TPPs) in the Russian Federation and the published investigation materials from Russian and foreign experts in this field, a comparative analysis of the radioactive emissions into the environment was performed for NPP emissions, as well as emissions from TPPs that operate using coal. It is shown that the total contents of radioactive nuclides in the TPP emissions substantially exceed those from NPPs, even for modern TPPs that operate using coal with ash contents of not more than 10% equipped with a filtering system that allows the removal of not less than 97.5% of the ash. An especially difficult situation for TPPs is due to long-lived radioactive isotopes, which are disposed practically without monitoring (and have a greater quantity of radioactive waste than NPPs by several orders of magnitude) with slag and are released into the atmosphere with the ash of organic fuels (particularly, shale oil, and coal).  相似文献   

6.
刘军  许甫荣  郑春开  沈文庆 《物理》2003,32(5):332-336
第一讲和第二讲系统地介绍了核科学发展历史,特别是核科学中的历史性发现和重大应用.主要综述核科学的早期发展历史,总体介绍核科学中最基本的重大发现,如放射性、电子、质子、中子、原子核裂变和衰变的发现.介绍人类认识原子和原子核的历史过程,包括与之相关的著名实验和理论.通过介绍核科学的发展和应用,展示了核科学技术对自然科学本身及其对人类社会的深远影响和巨大贡献.  相似文献   

7.
刘军  许甫荣  郑春开  沈文庆 《物理》2003,32(5):337-340
4 核反应、核裂变和核聚变放射性衰变是某些不稳定原子核自发产生的一种核蜕变反应 ,它只和发生蜕变的那个核本身的性质有关 ,而不需要外界的影响 .那么 ,有没有办法通过外界影响使本身稳定的原子核产生变化呢 ?自从卢瑟福和合作者在 1 90 9— 1 91 0年通过用α粒子做“炮弹”轰击原子 ,并由散射α粒子的角分布推论出原子的核式结构以来 ,人们就认识到 :要探索微观世界的奥秘 ,就必须利用能深入到微观粒子内部的“炮弹粒子” ,使两个微观粒子相撞 ,发生变化 ,然后从发生的变化推断它们的行为和内部结构[1] .由于原子核很小 ,其半径只有 1 0…  相似文献   

8.
Power ultrasound, as an emerging green technology has received increasing attention of the petroleum industry. The physical and chemical effects of the periodic oscillation and implosion of acoustic cavitation bubbles can be employed to perform a variety of functions. Herein, the mechanisms and effects of acoustic cavitation are presented. In addition, the applications of power ultrasound in the petroleum industry are discussed in detail, including enhanced oil recovery, oil sand extraction, demulsification, viscosity reduction, oily wastewater treatment and oily sludge treatment. From the perspective of industrial background, key issue and resolution mechanism, current applications and future development of power ultrasound are discussed. In addition, the effects of acoustic parameters on treatment efficiency, such as frequency, acoustic intensity and treatment time are analyzed. Finally, the challenges and outlook for industrial application of power ultrasound are discussed.  相似文献   

9.
An energy-content-based criterion of assessing the detonability of organic HEs is proposed. The energy content of HEs is demonstrated to be a quantitative measure of the detonability, which can be estimated using the chemical composition and enthalpy of formation of the HE.  相似文献   

10.
The state of studies of high explosives is examined. The limiting possibilities of organic high explosives in the detonation velocity, metal acceleration ability, and energy stored are assessed. The prospects of development of research in this field are discussed.  相似文献   

11.
The literature on "contrast" provides no evidence that durational contrast should occur in the speech and nonsence signals used in research cited by Diehl et al. [J. Acoust. Soc. Am. 89, 2905-2909 (1991)]. Moreover, there is evidence that, in comparable signals, it does not occur. Accordingly, their own account of the collection of findings on rate normalization is not viable. Their comments on my research do not imperil my interpretation of it or challenge my criticism that classification judgments of acoustically analogous speech and nonsense signals do not permit interpretation, by themselves, in terms of underlying auditory-system mechanisms. Their arguments that in auditory perception, uniquely, we hear proximal stimulation, not its physical causal sources, is implausible. Their theoretical perspective generally, I argue, is unrealistic.  相似文献   

12.
The nuclear winter phenomenon is used to illustrate the many paths by which scientific advice reaches decision makers in the United States government. Because the Reagan administration was hostile to the strategic policy that the scientific discovery seemed to demand, the leading proponent of nuclear winter, Carl Sagan, used his formidable talent for popularization to reach a larger audience.  相似文献   

13.
Often considered as the last ‘encyclopedist’, Henri Poincaré died one hundred years ago. If he was a prominent man in 1900 French Society, his heritage is not so clearly recognised, particularly in France. Among his too often misunderstood works is his contribution to the theory of relativity, mainly because it is almost never presented within Poincaré's general approach to science, including his philosophical writings. Our aim is therefore to provide an historical account of the main steps (experimental as well as theoretical) which led Poincaré to contribute to the theory of relativity. Starting from the optical experiments which led to the inconsistency of the classical (Galilean) composition law for velocities to explain light propagation, we introduce the FitzGerald and Lorentz contraction which was viewed as the ‘sole hypothesis’ to explain the Michelson and Morley experiment. We then show that Poincaré's contribution starts with a discussion of the principles governing the mechanics and was built step by step up to express in all its generality the principle of relativity. Poincaré thus showed the invariance of the Maxwell equations under the Lorentz transformation. In doing so, he also discovered the right composition law for velocities. Poincaré's approach to philosophy is detailed to help the reader to understand what a theory meant to him.  相似文献   

14.
Observations of GeV heavy ion and MeV cluster-ion tracks in crystalline solids give us new insight into registration physics. Thermal and ion explosion spikes no longer compete; a ‘compound spike’ accounts for both. Ion explosion dominates for surface tracks (electronic sputtering). And there can also be transient plasma stopping in the bulk. For clusters there are ‘vicinage effects’—both electronic and nuclear—which can influence track dimensions and structure. Displacement cascades in large energetic clusters may lead to projectile “fission” and coherent flow into sub-tracks. The absence of tracks in certain targets, and their size/structure in others, leads to a model of projectile assisted prompt anneal (PAPA) in 10−11s, either partial or complete, often by swift epitaxy, on elemental lattices (e.g. silicon) or on compound sublattices (e.g. fluorite). Phase transformations are important, but simple target amorphization is rare—the exception, not the rule. For many targets the thermal spike (macroscopic) fails, since ‘point’ defects (atomistic) characteristic of the target, their motion, and the electronic band structure, determine latent track detail. Circumstances in which the Bragg Rule of Additivity fails completely are revealed, and the kinetic threshold for constructive phase transitions in tracks described. This same track physics applies generally also to geothermometry—the opposite time extremum (10+11s)—where annealing is due to defect assisted delayed anneal (DADA). Differences between etching rates of induced and spontaneous fission tracks can be explained. The geothermobarometric “Wendt/Vidal effect” (2002)—combined pressure, temperature and stress (with time) influences on fission track annealing (in e.g. apatite)—is briefly discussed.  相似文献   

15.
No energy, whether renewable, clean or known by any other name can possibly be relied upon as the only solution for ensuring a supply of electricity compatible with a nation’s economic and social development. Brazilian consumption and installed capacity of electric power generation per capita indices are still inadequate and below the world average—this crucial fact must be considered. It obliges Brazil to take the most advantage of all resources available to increase its electricity generation capacity as rapidly as possible, thereby enabling consumption to reach levels compatible with the quality of life the Brazilian population aspires to. Planning of a country’s electric system requires efficient management of a diversified portfolio of energy sources. In Brazil, hydroelectricity will continue for many years yet to be the main component of its portfolio of electric power generation sources, but it must be supplemented by thermal sources—uranium, coal, biomass, natural gas, and oil by-products derived from petroleum—in this order of importance, keeping in mind aspects related to local availability, cost, environmental impacts, and use in other applications.  相似文献   

16.
提出了改进的核密度模型, 用唯象的方法找到了束缚核子内价夸克和海夸克的 核效应的参数公式, 其中利用了我们已经建立的核密度与原子核的平均结合能 之间的联系. 利用该模型所得到的束缚核子内部分子分布函数, 对轻子与核 的DIS(深度非弹性散射)过程的核效应给出了满意的解释, 深化了对原子核内夸克分布受核效应影响的认识.  相似文献   

17.
18.
Nuclear-type estimators of the power spectrum and the correlation function of a stationary Gaussian stochastic process are proposed and investigated for the case in which the measurement times form a recurrent time series.Branch of the Tomsk Pedagogical Institute, Anzhero-Sudzhensk. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 2, pp. 55–66, February, 1994.  相似文献   

19.
20.
The state of development of autoradiographic techniques and the limits of their applicability are considered in order to outline the possibilities and conditions of obtaining both qualitative and quantitative informations from autoradiographs.

The constraints of further development of classical autoradiographic techniques as well as new possibilities of enlarging the coverage of autoradiography by making use of new detection techniques are indicated.  相似文献   

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