共查询到20条相似文献,搜索用时 93 毫秒
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核聚变与核裂变可以说是核能的一对孪生兄弟.氘的聚变反应是在1934年世界上第一台加速器投入运行后不久就实现的,而铀的裂变反应直到1938年底才被发现.然而,裂变能源的发展一帆风顺而聚变能源的探索却道路曲折.早在1942年就建成了具有功率输出的实验性裂变反应堆,50年代就建成了商用核电站.而核聚变直到最近才基本证明了它的科学可行性,90年代可建成具有功率输出的实验反应堆,要到21世纪初才能发展商用聚变核电站.这是因为实现受控核聚变的条件实在太苛刻了!首先要使等离子体达到1亿度的极高温度,并且维持足够长的时间,以便产生足够多的聚变反应,释放大量的能量. 相似文献
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核能有两个最具影响的应用:一是它的和平利用——核电(第四讲介绍),另一是它的军事应用——核武器.文章将介绍核能和核武器基本原理以及核燃料生产方法.首先简要介绍核裂变能与聚变能;然后比较详细地说明原子弹的基本原理,包括中子增殖、自持裂变链式反应条件、临界质量和两种形式原子弹的结构原理等,对于氢弹、中子弹的原理仅作简单介绍;最后,对核燃料的生产:铀同位素分离和钚—239的反应堆生产作了原理性的介绍。 相似文献
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受控热核聚变 总被引:1,自引:0,他引:1
1能源的需求
能源对于人类的生活和社会的发展极为重要.随着工业的进步,能源的需求益见迫切.煤、石油、天然气、风力、水力已早为人们习惯使用,地热、太阳能以及裂变核能亦已相继开发利用.但它们或受地区的限制,或存在污染的缺点使用都有不便,或与环境保护有碍,尤其矿石类燃料及天然气等在地球上储量有限,不断开掘,迟早会枯竭.表1表示全世界能源的估计.目前世界主要能源的消耗每年约需3×10 11GJ,表1数据依此估出,以后的消耗将续有增加,按其储量足供人类使用不过百年,而且煤和石油是化工的原材料,用作燃料,付之一炬,未免可惜.如果使用增殖堆发电,可以维持几万年,似是久远之计,但放射性废料的处理实是棘手问题.不久前美国三里岛事故和前苏联的切尔诺贝利泄漏使人深俱戒心. 相似文献
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核裂变是自然科学史上一件重大事件.核裂变导致原子核能的应用,使人类掌握了新的重要能源;同时由于超级大国争霸世界的意图,使第二次世界大战后四十余年全世界人民经常处于核战争的威胁中.因此,核裂变不但是科学史上的重要事件,同时也是对保卫世界和平有重大意义的事件. 现在我们简单回顾一下裂变发现前后的历史. 第一次世界大战结束后,英国卢瑟福和他的同事们用镭和它的子体放出的最快的α射线去打击较轻的元素氮,发现氮能变成氧,放出质子,成功地打开了人工改迭原子核的大门.这个现象叫做原子核的“人工嬗变”,是1919年发现的. 从1930-1932… 相似文献
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能源短缺和环境恶化是人类社会面临的共同挑战.由于资源丰富、环境友好和零碳排放,核聚变能源是未来的理想能源.上世纪90年代以来,磁约束核聚变研究取得重大进展,以建造国际热核实验反应堆(ITER)为标志,聚变能源开发进入工程实施阶段,如果ITER计划取得预期成果,有望在本世纪中叶实现核聚变能源商用化. 相似文献
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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
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在气象预报、天体物理、能源探测、核武器设计、核聚变研究等科学和工程领域经常应用大规模科学计算,其中很多计算需要超级计算环境。传统的串行处理方式难以满足这些要求。因此,现代高性能计算主要采用并行计算方式。 相似文献
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M. Tabak 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,44(2):265-272
There is a need to develop alternate energy sources in the coming century because fossil fuels will become depleted and their
use may lead to global climate change. Inertial fusion can become such an energy source, but significant progress must be
made before its promise is realized. The high-density approach to inertial fusion suggested by Nuckolls et al. leads reaction
chambers compatible with civilian power production. Methods to achieve the good control of hydrodynamic stability and implosion
symmetry required to achieve these high fuel densities will be discussed. Fast Ignition, a technique that achieves fusion
ignition by igniting fusion fuel after it is assembled, will be described along with its gain curves. Fusion costs of energy
for conventional hotspot ignition will be compared with those of Fast Ignition and their capital costs compared with advanced
fission plants. Finally, techniques that may improve possible Fast Ignition gains by an order of magnitude and reduce driver
scales by an order of magnitude below conventional ignition requirements are described. 相似文献
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本文开拓性地提出了一种新型多种化石能源输入(煤和天然气)、多种产品输出(电力和化工产品)的多功能能源系统。该系统将天然气/水蒸气重整过程和煤的燃烧过程有机整合,用煤燃烧替代了传统重整过程清洁的燃料天然气和弛放气燃烧,实现了煤和天然气的综合互补利用;将甲醇生产系统与发电系统有机整合,实现了化工系统弛放气的梯级利用同时,对甲醇生产系统余热进行了更加有效的利用。研究表明生产相同量的甲醇和电,多功能系统比参比系统少消耗 20%的天然气。本文工作为煤和天然气综合高效利用提供了新途径. 相似文献
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Obaidullah Mohiuddin Madina Obaidullah Cumali Sabah 《Optical and Quantum Electronics》2018,50(10):377
Several emerging renewable technologies are available to satisfy the current energy demand and to minimize the effect of environmental degradation caused by high consumption of fossil fuels. These technologies are not mature enough to solve this problem but require more time for improving the efficiency, and cost reduction to become the economical alternative of fossil fuels. In this paper Dye-sensitized solar cell (DSSC) has been discussed in detail owing to advancement in the technology. Since each component of DSSC is responsible for a specific function, therefore, comprehensive literature studies has been done on individual section to understand the technology in depth. All the advancement in sensitizer, semiconductors, electrolyte, electrodes, additives, sealing and anchoring groups are included in this review with performance parameter of DSSC. Focus of this article is to provide summary of all available literature since beginning to date. 相似文献
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HyungKuk Ju Sarbjit Giddey Sukhvinder P. S. Badwal Roger J. Mulder Thomas R. Gengenbach 《Ionics》2018,24(8):2367-2378
Hydrogen at present is mainly produced from fossil fuels for use in ammonia synthesis, the petrochemical industry, and chemical production. In the future, hydrogen will be increasingly used as an energy vector. Although water electrolysis to produce hydrogen with renewable electricity offers a clean process, the approach is energy intensive, requiring a large renewable resource footprint. Methanol-water co-electrolysis can reduce the energy input by >?50%; its electrochemical oxidation poses complex issues such as poisoning of the catalyst, sluggish oxidation kinetics, and degradation over time. The addition of nano-sized SnO2 to PtRu/C catalyst, to reduce noble metal loading, has been shown here to reduce catalyst leaching and increase the chemical, micro-structural, and performance stability of the methanol-water co-electrolysis process during extended periods of testing. The electrochemical characterization, analysis of the methanol solution, and exit gases, post-cell testing, revealed complete oxidation of methanol with little performance degradation. This is further supported by the stability of the catalyst composition and structure as revealed by the post-mortem XRD and XPS analysis of the cell. The energy balance calculations show that methanol-water co-electrolysis can significantly reduce the renewable energy footprint, and the process can become carbon neutral if bio-methanol is used with renewable electricity. 相似文献
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光学与太阳能 总被引:1,自引:0,他引:1
开发资源丰富、可再生,清洁的新能源是全球一项紧迫的战略任务.在概述现有能源技术的基础上,从光学和光学技术角度重点对太阳能的直接利用、太阳能电池以及太阳能分解水制氰进行了分析.指出了利用简单有效的太阳能跟踪聚焦系统,以及耐热、低损耗、低成本和宽光谱传输的空芯塑料光纤,可以加大对太阳能的直接利用和普及推广;在太阳能电池方面,应重点研究和发展各种薄膜太阳能电池,采用对可见、紫外和红外光谱吸收的、具有不同带隙的复合材料和采用多结器件,以进一步提高电池的转换效率和降低成本;在太阳能分解水制氢方面,应该把直射到地球表面的、从紫外-可见-红外的宽太阳光谱,利用空腔辐射器作一个变换,转换成绝大部分位于水分子有强烈吸收带的红外区.同时利用催化剂(敏化剂),对水进行红外光催化分解反应,或者利用红外多光子离解这有可能取得工业化规模制氢的突破. 相似文献
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A.R. Masri 《Proceedings of the Combustion Institute》2021,38(1):121-155
Turbulent combustion will remain central to the next generation of combustion devices that are likely to employ blends of renewable and fossil fuels, transitioning eventually to electrofuels (also referred to as e-fuels, powerfuels, power-to-x, or synthetics). This paper starts by projecting that the decarbonization process is likely to be very slow as guided by history and by the sheer extent of the current network for fossil fuels, and the cost of its replacement. This transition to renewables will be moderated by the advent of cleaner engines that operate on increasingly cleaner fuel blends. A brief outline of recent developments in combustion modes, such as gasoline compression ignition for reciprocating engines and sequential combustion for gas turbines, is presented. The next two sections of the paper identify two essential areas of development for advancing knowledge of turbulent combustion, namely multi-mode or mixed-mode combustion and soot formation. Multi-mode combustion is common in practical devices and spans the entire range of processes from transient ignition to stable combustion and the formation of pollutants. A range of burners developed to study highly turbulent premixed flames and mixed-mode flames, is presented along with samples of data and an outline of outstanding research issues. Soot formation relevant to electrofuels, such as blends of diesel-oxymethylene ethers, hydrogen-methane or ethylene-ammonia, is also discussed. Mechanisms of soot formation, while significantly improved, remain lacking particularly for heavy fuels and their blends. Other important areas of research, such as spray atomization, turbulent dense spray flames, turbulent fires, and the effects of high pressure, are briefly mentioned. The paper concludes by highlighting the continued need for research in these areas of turbulent combustion to bring predictive capabilities to a level of comprehensive fidelity that enables them to become standard reliable tools for the design and monitoring of future combustors. 相似文献
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Z-Pinch惯性约束聚变是未来一种有竞争力的能源候选方案。Z-Pinch驱动的聚变裂变混合堆可高效地嬗变反应堆乏燃料中分离出的超铀元素。对美国Sandia国家实验室提出的In-Zinerater混合堆概念进行了中子学分析和数值模拟。在三维输运燃耗耦合程序MCORGS中增加了处理在线添加燃料与去除裂变产物的功能,实现了对液态燃料燃耗过程的模拟。增加6Li丰度和燃料初装量保持寿期初反应性不变,可以减缓寿期内反应性下降趋势。逐步增加包层内超铀元素装量,可以控制整个寿期内反应性基本恒定。聚变功率取20 MW,通过反应性控制,5年内包层能量放大倍数在160~180之间,氚增殖比在1.5~1.7之间,优于In-Zinerater基准设计方案。 相似文献
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S. Kullander 《The European physical journal. Special topics》2009,176(1):115-125
The potential future bioenergy contribution to the global energy supply is outlined. Severe constraints have to be applied
since biomass is used for many different purposes. It is likely that biofuels from primary agricultural products may not increase
much above the current 1% of all liquid motor fuels in order to secure food for people and cattle. Bioenergy from forestry
should only be used whereever it is absolutely essential. Deforestation results in a net emission of CO2 to the atmosphere that is equal to that of the USA. Rather than to replace fossil fuels by forest bioenergy, deforestation
must be halted. The management of the Swedish annual forest growth shows how a carbon sink can be developed in parallel with
biomass for energy and industry. The most promising way of getting energy from biomass is to use the residues in forestry
and agriculture. If this is properly done the current annual global bioenergy may double from its present value of 13,000
TWh in the next few decades. 相似文献