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主题:【原创】热核聚变笔记 -- 滕诺

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家园 没有民族有资格界定谁优劣,但是有产业文化可以界定谁优劣

中国之所以优秀,是因为皈依了科学和产业的文化。当然问题还很多,不能说完全采纳,还是一个长期的过程。但是起码证明了中国人是优秀的。只是人太多,需要时间罢了。

其他民族也完全可以皈依,波斯人就在皈依,不过可惜的是能源短期内不足以供应。所以其皈依必然失败,但是那也是虽败犹荣。等到解决了能源问题之后,无论是那一种名义也是要拉一下的。

不皈依而坚决拒绝的,那就是劣等民族,而劣等民族已经被世界抛弃了。只不过是时间早晚而已。既然不过是时间早晚,那就应该加速。而这只有帝国才能做到。帝国在盘剥上绝对是有效率的机器。

家园 又出夭娥子了:

世界最大科学工程之一ITER面临延误困境

虽然基础设施已经铺设,但是ITER建设由于复杂的合约处理方式而面临延误。

图片来源:ITER ORGANIZATION

本报讯(记者唐凤)目前,世界上最大的科学工程之一 ——国际热核聚变实验堆(ITER)计划——正遭遇进一步推迟的威胁。原因是各机构正在争相完成相关设计,并试图与工业合作者签署价值数百亿欧元的合约。

 

 

ITER计划是目前全球规模最大、影响最深远的国际科研合作项目之一,旨在探索核聚变反应作为能源生产者使用的可行性,以解决人类未来能源问题。其装置主要包括一个环形的被称为托卡马克装置的反应堆,包裹着超导磁体的托卡马克装置就像一个“磁笼”,氢同位素等离子体就被约束在这“磁笼”中,被不断挤压和加热从而接近聚变条件。受控的核聚变反应能够释放超过社会消耗量十倍的能量。

 

 

但是,这还只是一个梦想。

 

 

到目前为止,ITER计划已经耗费了大量金钱和时间。《自然》杂志报道指出,2006年,ITER计划的七个国际成员签署协议以来,其报价已经达到150亿欧元(约合194亿美元),并且竣工时间推迟到2020年底。而工期拖延和成本攀升的主要原因之一在于广泛的设计审查——该审查工作完成于2009年。

 

 

祸不单行,前不久,熟悉ITER计划运作的人士警告称,用于购买ITER设备各种部件的复杂体系还会进一步拖延工期。

 

 

根据规定,ITER计划的合作伙伴需要抵押实物而非付以现金,来资助该装置建设所需部件。这样一来,磁铁、仪器以及反应堆设备可能来自世界各地,这些部件将拼凑起位于法国南部St Paul lès Durance的ITER中央站。同时,由于没有掌管财务的机构,ITER中心组织和各成员国“国内机构”的装置部件设计也面临曲折往复问题。

 

 

另外,托卡马克装置建筑的施工建设承包给了F4E——欧洲的内部机构。但是,ITER组织无法告诉该机构需要建设什么,ITER技术总监Rem Haange表示,直到F4E从其他国家机构的诸多系统和子系统那里收集到有用的数据,工程才开始。

 

 

2011年,Haange接手工作时,工期已经严重落后于预定计划。不过,他表示自己将坚定地按照时间表推进工程进度,努力追回损失的时间。最终的设计方案将在明年3月完成,但是按照预定时间,F4E必须在今年年末提交工程合同。

 

 

除此之外,F4E还在另一个主要合约——建造环绕机器的巨大极向场线圈上面临困难。

 

 

2009年,ITER组织授权F4E采购所需要的线圈,但是他们只收到一个来自法国Alstom公司和德国Babcock Noell公司的联合竞标。F4E驳回了这一竞标,因为它给出的价格远远高于F4E的预期价格。

 

 

Alstom公司的发言人表示,在漫长而又艰难的技术和商业磋商后,竞标失败了。不过,F4E发言人Aris Apollonatos则指出,现在,合约将被拆分成7个部分,以便使其更具吸引力。“本月早些时候召开的一次会议上,有27家公司对此表示出兴趣。”他说。

 

 

尽管目前时间紧迫,Haange和Apollonatos表示,在下个月于法国卡达拉舍举行的ITER理事会议上,他们不会要求更多的时间。“我们只有在工程确实需要更多时间的情况下,才会向理事会提出额外的时间要求。”Haange说。

 

 

但是,坚持启动时间表也可能耽搁首次能量生产实验的进行,目前其预定启动时间大约在2027年末或2028年初。因为这些实验需要氢的放射性同位素——氚,但是,为了确保总体工程按照目前预算和时间表进行,所需氚的生产设备建设不得不推迟,Haange表示。“我们必须寻求适当的方法,弥补这些潜在的时间延误。”他说。

 《中国科学报》 (2012-10-29 A2 国际)

http://www.stdaily.com/stdaily/content/2012-10/29/content_534088.htm

========================

三个和尚没水吃。。。

家园 概念完全错误了

引用:“原子也是由质子中子和电子组成,组成时会放出能量,这个能量称为原子的结合能,同时损失一部分原有的总体质量……”

——原子的组成过程不一定释放能量,以铁为中心,比铁轻的原子核发生聚变时释放能量,比铁重的原子核发生裂变时释放能量,反之则都吸收能量。铁核的能态最低,铁核无论发生聚变还是裂变都吸收能量,这个性质也是大质量恒星在生命末期发生超新星爆发的重要成因之一——铁芯灾变。

引用:“如果原子组成之后,尤其是原子核形成后,要打开这个原子需要与结合能相同的能量,这个有点类似于化学反应与逆反应。”

——不能这么类比,而且打散一个原子需要的能量未必是和结合能相同的,原子核尺度下的物质性质和宏观世界完全不同。

引用:“先有外来的中子轰击,带来的能量高于重核的结合能,于是重核裂变……”

——原子核发生裂变的原因是弱力,其原理不是外来中子的能量那么简单。

家园 氢原子也就一层电子,一个电子,也就全部了。
家园 不仅仅是氢

在恒星的内核,只要恒星的质量足够大,氢聚变生成的氦甚至碳、氮、氧等元素都会发生聚变,这些元素在恒星内部都是没有电子层的。元素的原子核外有没有电子层由温度决定,只要温度足够高,电子都会逃逸的只剩原子核,热核聚变全都是在这种情况下发生的。存在外层电子的原子发生核聚变不是不可能,只是概率实在太小了。

家园 请问,电子跑哪去了?
家园 电子都成为了自由电子

恒星的星核就是一锅元素的核和自由电子组成的“浓汤”,在托克马克装置中,因原子核和电子的质量差别很大,二者在磁场中的回旋半径不同,反应区内是纯粹的核子。

家园 铍对中子透明
家园 是不是几乎所有的物质都对中子透明啊?不过是透明率有点差别
家园 证实了,汗,伪装都不要了,直接说是研究核弹头的了。

《自然》杂志报道,因为试验效果不尽理想,NIF将会把目前占到80%的科研时间压缩到50%,并且继续解决存在的问题,而NNSA将会获得更大的控制权

Laser lab shifts focus to warheads

After an unsuccessful campaign to demonstrate the principles of a futuristic fusion power plant, the world’s most powerful laser facility is set to change course and emphasize its nuclear weapons research.

For the past six years, scientists and engineers at the US National Ignition Facility (NIF) have been working flat out to focus 192 laser beams on a gold-lined ‘hohlraum’ capsule, just a few milli-metres long, containing a pellet of hydrogen isotopes. As 500 terawatts of laser power hits the capsule, it generates X-rays that blast into the pellet, causing the atoms of deuterium and tritium inside to fuse. The fusion converts a tiny amount of their mass into a burst of energy (see ‘The NIF’s fusion strategy’).

The goal of the National Ignition Campaign (NIC) is reflected in its name: ‘ignition’, in which the fusion reaction generates as much energy as the lasers supply. Success, NIF officials say, could pave the way to developing a power plant that would implode nearly 1,000 pellets a minute (see Nature 483, 133–134; 2012). But unexpected technical problems left the NIF well short of its goal when the campaign finally ended in September.

Now federal officials and the US Congress are preparing to set a new direction for the US$3.5-billion facility at the Lawrence Livermore National Laboratory in California. A series of reports commissioned by the government, Congress and the University of California, which administers the lab, are all due later this month. They are expected to outline plans to cut its time for ignition research from 80% to 50% and to give the National Nuclear Security Administration (NNSA), which is responsible for maintaining the US nuclear arsenal, a more central role in determining the NIF’s priorities. The NNSA is planning to emphasize experiments that mimic conditions inside nuclear weapons, generating data to validate the computer codes used to check that the nation’s warheads remain viable — essential work, given the voluntary moratorium on underground testing that began in 1992.

Nobody has given up on ignition, declares Donald Cook, deputy administrator for defence programmes at the NNSA. But a new programme for generating net energy will take a slower, more methodical approach. “We’re now going to get right into the science of what issues are preventing ignition and work through them,” he says. “But we believe that’s going to take a fair amount of work.”

Significant progress has already been made towards ignition, according to physicist Robert Byer at Stanford University in California, who is leading the University of California’s review of the NIF. “The laser itself has been quite remarkable,” he says. One shot can deliver 1.85 megajoules of energy, roughly what the lab originally promised. The instruments used to study the pellet are also performing well, he says.

Yet on the basis of data obtained from the imploding pellets, researchers think that they are still far from reaching the conditions necessary for ignition. One problem seems to be that too much of the laser light is scattering back out of the capsule. Another is that the pellet is being squeezed asymmetrically, which lowers the pressure at its centre. The asymmetry also causes the isotopes to mix unevenly, lowering the temperature in the pellet. “Nature pushes back: that’s my shorthand version of what’s going on,” Byer says.

Nature isn’t the only one pushing back — the NIF’s funders in Congress also want answers. “We’re disappointed,” says one congressional staff member, who spoke to Nature only on condition on anonymity. Critics say that the lab’s enthusiastic promotion of the idea that laser fusion could generate electrical power led many in Congress to believe that they were funding an energy project, when in fact laser fusion is decades from producing electricity. “The lab overemphasized and oversold the energy aspect of the NIF, at the expense of the very important and successful work it was doing in stockpile stewardship and basic science,” says a senior scientist familiar with the NIF programme.

The NIF’s current director Ed Moses bridles at accusations that ignition was over-emphasized. “I don’t think it was oversold or undersold. It just was.” Moses insists that “remarkable progress” has been made in the past 16 months, since the NIF began working with hydrogen-pellet targets. “The goal was to do the initial exploration of the ignition conditions and see where we were, which is what we’ve done.”

But there is likely to be less time for ignition experiments in the coming year, says Cook. Livermore will still control the programme’s day-to-day operation, but the NNSA’s headquarters in Washington DC will set priorities as the facility expands its stockpile stewardship work. Already, the NIF has been able to address crucial questions about how energy passes from the fission stage of a nuclear weapon to its much more powerful fusion stage. Future research will assess the ‘boost phase’ of the weapon — during which a small quantity of deuterium and tritium at the centre of the first stage is used to boost the initial fission phase of the explosion.

The shift in priorities worries Riccardo Betti, a laser fusion researcher at the University of Rochester in New York. “They have to make sure that the ignition effort doesn’t become subcritical,” he warns.

Keeping momentum in the ignition campaign may be crucial, because many in Congress still believe in the energy-research mission being pushed by the lab. Lawmakers have mandated that a new plan for reaching ignition be delivered to them by the end of the month. Politicians are ready to accept that it may take longer than originally stated, but they need to see evidence that it is on course, the congressional staff member says: “It can’t just be an open-ended: ‘Just give us money, we promise we will do good science’.” And if the NIF fails to reach its ignition goal in a few more years? “Then we’ll have to evaluate whether it’s worth continuing to fund the facility.”

nature.com/news/laser-lab-shifts-focus-to-warheads-1.11745

家园 【讨论】大家都没有关注到冷核聚变的最新进展吗?

NASA承认冷核聚变了:

原文地址:http://technologygateway.nasa.gov/media/CC/lenr/lenr.html

中文翻译:

http://www.tudou.com/programs/view/murxMJdsx5s

而且,清华大学也开了个研讨会:

http://www.tsinghua.edu.cn/publish/ep/1231/2012/20120423093217232290858/20120423093217232290858_.html

看这个意思也是认可了那个意大利Rossi团队的成果!

大家对此有何看法?

有国外消息灵通的,说说这方面的进展,就是意大利Rossi团队的产品到底如何?据说要在希腊建立一个10kW的反应堆哦!

家园 现在国家点火装制科研时间被砍了一半

由于进展不顺利,前景不看好。以后更多地有于核武器研究。

家园 这玩意要搞成了

石油马上从能源降为重要化工原料。

中东油国们集体仆街。

普大帝也惨了,外汇收入崩盘,国民福利拿啥买单?莫非要靠在西伯利亚发展伐木业解决?

中国立马解决雾霾问题,还可以轻轻松松引渤入疆化沙漠为良田。

指望北海石油收入搞苏格兰独立的想法彻底歇菜

就是……靠谱么?

这位Rossi老兄不会被石油公司买凶干掉吧?

家园 这东西搞成了

新疆可以稳定下来了,但是中国周边尤其是西部周边国家要乱了,但也是PLA走出去的前奏啊。。。

家园 几个错误~~

1)由于地球中的铀等放射性元素储量有限,且这些大分子不稳定、放射性半衰期长,资源有限且污染环境,而热核聚变则没有这个问题。

能裂变的原子核并非一定是放射性的,如U238其实很稳定了,半衰期高达43亿年。

不是大分子,是重原子核。

不稳定应该是半衰期短,半衰期长应该是稳定。

热核聚变也有污染,那么强的中子流,照到哪里哪里就成了放射源。

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