发帖数: 1 | 1 橡树岭国家实验室散裂中子源诚招有物理和计算背景的博后。
课题为运用高性能计算增强非弹性散射中子谱仪的分辨率。年薪约$65k。
https://recruiting.ornl.gov/sap/bc/webdynpro/sap/zornl_hrrcf_c_post_doc?sap-
language=EN&sap-client=010#
Job Posting Title
Postdoctoral Research Associate in Super-Resolution Inelastic Neutron
Scattering
Purpose
The Neutron Sciences Directorate (NScD) at Oak Ridge National Laboratory (
ORNL) operates the High Flux Isotope Reactor (HFIR), the United States'
highest flux reactor based neutron source, and the Spallation Neutron Source
(... 阅读全帖 |
|
发帖数: 1 | 2 橡树岭国家实验室散裂中子源诚招有物理和计算背景的博后。
课题为运用高性能计算增强非弹性散射中子谱仪的分辨率。年薪约$65k。
https://recruiting.ornl.gov/sap/bc/webdynpro/sap/zornl_hrrcf_c_post_doc?sap-
language=EN&sap-client=010#
Job Posting Title
Postdoctoral Research Associate in Super-Resolution Inelastic Neutron
Scattering
Purpose
The Neutron Sciences Directorate (NScD) at Oak Ridge National Laboratory (
ORNL) operates the High Flux Isotope Reactor (HFIR), the United States'
highest flux reactor based neutron source, and the Spallation Neutron Source
(... 阅读全帖 |
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z**h
发帖数: 224 | 3 【 以下文字转载自 Chemistry 讨论区,原文如下 】
发信人: zzwh (Timing Bell), 信区: Chemistry
标 题: 有没有做NEUTRON 或X-RAY REFLECTIVITY的，都用什么软件FIT DATA 呀?
发信站: The unknown SPACE (Sun Feb 9 13:03:26 2003) WWW-POST
Thanks> |
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d**m
发帖数: 94 | 4 You mean Neutron Scattering? Igor Pro, www.wavemetrics.com. Check NIST website
at www.ncnr.nist.gov. |
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z******i
发帖数: 38 | 5 fresh Ph.D, 希望能求到一些review paper，我主要方向是polymer nanocomposites,
surface modification using APRP, surface morphology study using x-ray and
neutron reflectivity.具体的情况可以附上CV。希望如果有ID收到review 愿意转让的
联系。感激不尽。谢谢了。 |
|
v**********m
发帖数: 5516 | 6 Uranium Resources CEO Discusses Q1 2012 Results - Earnings Call Transcript
Uranium Resources CEO Discusses Q1 2012 Results - Earnings Call Transcript
May 11, 2012 | about: URRE
Presentation
Q&A
Participants
Uranium Resources (URRE) Q1 2012 Earnings Call May 11, 2012 11:00 PM ET
Operator
Greetings and welcome to the Uranium Resources Incorporated First Quarter
2012 update conference call. At this time all participants are in a listen-
only mode. A brief question-and-answer session w... 阅读全帖 |
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v**********m
发帖数: 5516 | 7 Uranium Resources, Inc. Signs Definitive Agreement To Acquire Neutron Energy
, Inc. And Executes Financing Agreement With Resource Capital Fund
Thursday, 1 Mar 2012 09:44pm EST
Uranium Resources, Inc. announced that it has entered into a merger
agreement to acquire 100% of the equity capital of Neutron Energy, Inc. (
Neutron) in a stock-for-stock transaction (Transaction). At the same time as
the Transaction, an affiliate of Resource Capital Fund V L.P. (RCF) will
provide $20 million that will b... 阅读全帖 |
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j**y
发帖数: 80 | 8 北京时间10月16日22时，国际天文界宣布了最新的科学进展：首次直接探测到双中子星
并合引力波及其伴随的电磁信号。这标志着人类历史上第一次使用引力波天文台和其他
望远镜观测到同一天体物理事件，预示着天文学研究进入“多信使”时代。中国“慧眼
”望远镜与紫金山天文台均成功监测到此次引力波事件。
来源：译·世界（ID：yeeworld）
这两天，国内外天文圈不约而同地卖起关子——纷纷声称要有大事宣布，却又个个神秘
兮兮、守口如瓶。
终于，北京时间10月16日22时，国际天文界宣布了最新的科学进展：首次直接探测到双
中子星并合引力波及其伴随的电磁信号。这标志着人类历史上第一次使用引力波天文台
和其他望远镜观测到同一天体物理事件，预示着天文学研究进入“多信使”时代。中国
“慧眼”望远镜与紫金山天文台均成功监测到此次引力波事件。
快随Yee君来感受下中子星并合产生引力波的模拟震撼效果~
A Chinese satellite helped define the energy level of a newly discovered
gravitational wave — tiny ripples ... 阅读全帖 |
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l**********p
发帖数: 272 | 9 【 以下文字转载自 Physics 讨论区 】
发信人: littleshrimp (芹菜), 信区: Physics
标 题: ZT funny post: Heaviest Element Yet Known to Science: (Gv)
发信站: BBS 未名空间站 (Fri Apr 27 14:10:37 2012, 美东)
Lawrence Livermore Laboratories has discovered the heaviest element yet
known to science. The new element, Governmentium (Gv) , has one neutron, 25
assistant neutrons, 88 deputy neutrons, and 198 assistant deputy neutrons,
giving it an atomic mass of 312.
These 312 particles are held together by forces called morons , which are... 阅读全帖 |
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l**********p
发帖数: 272 | 10 Lawrence Livermore Laboratories has discovered the heaviest element yet
known to science. The new element, Governmentium (Gv) , has one neutron, 25
assistant neutrons, 88 deputy neutrons, and 198 assistant deputy neutrons,
giving it an atomic mass of 312.
These 312 particles are held together by forces called morons , which are
surrounded by vast quantities of lepton-like particles called peons.
Since Governmentium has no electrons, it is inert; however, it can be
detected, because it impedes ev... 阅读全帖 |
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l**a
发帖数: 6415 | 11 删掉一些了。
链接如下
plainenglishnuclear.blogspot.com
.......
1. I live on the West Coast. Am I in danger?
No. Absolutely not.
You won’t even notice except that everyone will keep talking about it for
ages, and it’ll take us even longer to get off coal and oil and natural gas
because people will be afraid of nuclear power again. Go outside, get some
sunshine (or rain, depending), be grateful for the fact that your city isn
’t completely destroyed in an earthquake or a tsunami, hug your loved ones... 阅读全帖 |
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o********e
发帖数: 34 | 12 【 以下文字转载自 Macromolecules 讨论区 】
发信人: olivertree (Life is good), 信区: Macromolecules
标 题: Postdoc position at NIST
发信站: BBS 未名空间站 (Wed Feb 29 19:39:22 2012, 美东)
We are seeking candidates for a postdoctoral position focused on
understanding and controling the microstructures and dispersion in carbon/
polymer nanocomposites at the National Institute of Standards and Technology
's Center for Neutron Research, Gaithersburg, MD. The aim of the work is
to understand and control the microstructures and... 阅读全帖 |
|
o********e
发帖数: 34 | 13 【 以下文字转载自 Physics 讨论区 】
发信人: olivertree (Life is good), 信区: Physics
标 题: research scientist position at NIST (open for all nationalities)
发信站: BBS 未名空间站 (Mon Mar 17 16:54:23 2014, 美东)
The Macromolecular and Microstructure Sciences (MMS) team at the NIST Center
for Neutron Research (NCNR) is seeking a research scientist with a strong
record of creativity and achievement in any area of nano and microscale
science or instrumentation science. The candidate should complement and
expand current scien... 阅读全帖 |
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o********e
发帖数: 34 | 14 We are seeking candidates for a postdoctoral position focused on
understanding and controling the microstructures and dispersion in carbon/
polymer nanocomposites at the National Institute of Standards and Technology
's Center for Neutron Research, Gaithersburg, MD. The aim of the work is
to understand and control the microstructures and dispersion by studying the
self assembly of carbon nanoparticles. The primary tools will be Small
Angle Neutron Scattering (SANS) as well as Neutron Refelcto... 阅读全帖 |
|
o********e
发帖数: 34 | 15 【 以下文字转载自 Physics 讨论区 】
发信人: olivertree (Life is good), 信区: Physics
标 题: research scientist position at NIST (open for all nationalities)
发信站: BBS 未名空间站 (Mon Mar 17 16:54:23 2014, 美东)
The Macromolecular and Microstructure Sciences (MMS) team at the NIST Center
for Neutron Research (NCNR) is seeking a research scientist with a strong
record of creativity and achievement in any area of nano and microscale
science or instrumentation science. The candidate should complement and
expand current scien... 阅读全帖 |
|
o********e
发帖数: 34 | 16 【 以下文字转载自 Macromolecules 讨论区 】
发信人: olivertree (Life is good), 信区: Macromolecules
标 题: Postdoc position at NIST
发信站: BBS 未名空间站 (Wed Feb 29 19:39:22 2012, 美东)
We are seeking candidates for a postdoctoral position focused on
understanding and controling the microstructures and dispersion in carbon/
polymer nanocomposites at the National Institute of Standards and Technology
's Center for Neutron Research, Gaithersburg, MD. The aim of the work is
to understand and control the microstructures and... 阅读全帖 |
|
o********e
发帖数: 34 | 17 【 以下文字转载自 Macromolecules 讨论区 】
发信人: olivertree (Life is good), 信区: Macromolecules
标 题: Postdoc position at NIST
发信站: BBS 未名空间站 (Wed Feb 29 19:39:22 2012, 美东)
We are seeking candidates for a postdoctoral position focused on
understanding and controling the microstructures and dispersion in carbon/
polymer nanocomposites at the National Institute of Standards and Technology
's Center for Neutron Research, Gaithersburg, MD. The aim of the work is
to understand and control the microstructures and... 阅读全帖 |
|
o********e
发帖数: 34 | 18 【 以下文字转载自 Macromolecules 讨论区 】
发信人: olivertree (Life is good), 信区: Macromolecules
标 题: Postdoc position at NIST
发信站: BBS 未名空间站 (Wed Feb 29 19:39:22 2012, 美东)
We are seeking candidates for a postdoctoral position focused on
understanding and controling the microstructures and dispersion in carbon/
polymer nanocomposites at the National Institute of Standards and Technology
's Center for Neutron Research, Gaithersburg, MD. The aim of the work is
to understand and control the microstructures and... 阅读全帖 |
|
b***y
发帖数: 14281 | 19 既然有人争论方的学术水平，就上网搜了一下。应该说这个水平对于一个junior
faculty来说可以算是很牛B了，但是对于老方这种senior的已经搞了一辈子的人来说，
就只能算so so。不要说是院士，离aps fellow的级别也还差了不少。引用率最高的一
篇文章还是95年到了arizona之后跟老外合作的，被引118次，这也是方唯一一篇被引用
上百次的文章。可见方励之89之前确实没有做出过什么重要的工作，他的名声和地位绝
对是靠政治得来的，当然其中部分的也是80年在中国搞科普所得，必须承认科普工作也是
有重要的社会意义的。
(BTW，有人说你这个搜索未必完整。不错，确实不能保证100％毫无遗漏。但是我
用的search engine is THE search engine everybody in this community uses today.
So, if any article is not found by this search engine, sadly, it simply doesn't matter,
because no one would ever n... 阅读全帖 |
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a******e
发帖数: 17 | 20 以下是我一个哈佛物理博士朋友的回答。但愿能给你一点安慰。。。
Our family is planning a east coast vacation (for real) to outrun the
nuclear cloud drifting our way... I am kidding, but you may find the
following information entertaining, and potentially educational.
We need to put any risk in perspective. The main stream media is playing a
constructive roles here to report the risk as justified by the information
available and by the possible worst-case scenarios. Risk cannot be
discussed without quantification, otherwise i... 阅读全帖 |
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d*********e
发帖数: 1918 | 21 哈哈咱俩谁白痴啊，看来你这物理系的忘了粒子运动受阻
，速度变小，能量也变小啊。
你去看看hot neutron 是怎么变成 thermal neutron的？就是速度变小，能量对应变小了啊。
按你说的，透过水的hot neutron 能量一样，那你永远得不到thermal neutron了
题。 |
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l**********1
发帖数: 5204 | 22 En
温习一下 其十一年前的豪言 啊
中国科学：显著的发展和严峻的挑战
——历史演变和现状比较
于2001年12月4日 1st version
饶毅
本文在简要回顾中国科学史的基础上，介绍一些近年研究的内容，肯定中国
科学令人乐观的进步，并讨论可能的意义。同时也指出，中国优秀论文总量仍不
到世界的百分之一，低于中国经济在世界所占的百分比、也不能适应中国持续发
展的要求。中国科学的规模需要相当程度的扩大、质量有待进一步提高。中国科
技还存在面临许多问题和挑战。
中国科学历史上的优秀例子
一个国家科学研究状况可以近似地由发表论文的情况所反映。以下，本文主
要从生命科学的研究来讨论中国科学的情况，一方面这是我有一定判断力的领域，
另一方面生命科学是科学技术最重要的组成部分之一，可以反映科学主流。讨论
中国论文发表情况前，先谈两个背景：中国科学的历史情况，优秀科学和著名杂
志的关系。
奠定中国生命科学研究是二、三十年代协和医学院生理系林可胜和生化系吴
宪。他们不仅自己研究出色，而且培养和带领了其他研究者。林可胜在胃肠道生
理和神经生理有优秀工作。1942年，他在中国当选为美国科学院外籍院士，是... 阅读全帖 |
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k******6
发帖数: 7 | 23 Purpose
The Center for Nanophase Materials Sciences (CNMS) at Oak Ridge National
Laboratory (ORNL) is seeking a Postdoctoral Research Associate with
experience and expertise in organic spintronics, with a strong emphasis on
the design, fabrication and characterization of organic spintronic device.
The CNMS http://cnms.ornl.qov/ is a nanoscience research facility supported by the Office of Science, U.S. Department of Energy (DOE). The CNMS has a diverse spectrum of nanoscience activities includ... 阅读全帖 |
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k******6
发帖数: 7 | 24 Purpose
The Center for Nanophase Materials Sciences (CNMS) at Oak Ridge National
Laboratory (ORNL) is seeking a Postdoctoral Research Associate with
experience and expertise in organic spintronics, with a strong emphasis on
the design, fabrication and characterization of organic spintronic device.
The CNMS http://cnms.ornl.qov/ is a nanoscience research facility supported by the Office of Science, U.S. Department of Energy (DOE). The CNMS has a diverse spectrum of nanoscience activities includ... 阅读全帖 |
|
k******6
发帖数: 7 | 25 Purpose
The Center for Nanophase Materials Sciences (CNMS) at Oak Ridge National
Laboratory (ORNL) is seeking a Postdoctoral Research Associate with
experience and expertise in organic spintronics, with a strong emphasis on
the design, fabrication and characterization of organic spintronic device.
The CNMS http://cnms.ornl.qov/ is a nanoscience research facility supported by the Office of Science, U.S. Department of Energy (DOE). The CNMS has a diverse spectrum of nanoscience activities includ... 阅读全帖 |
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i******s
发帖数: 8734 | 26 1. Gray (Gy) the SI unit of absorbed dose. 1 Gy=1J/kg.
2. Rad: the special unit of absorbed dose. 1 rad =100 ergs/gram= 0.01 J/kg =
0.01Gy=1cGy.
3. Rem is the special unit of any of the quantities expressed as dose equiva
lent.
The dose equivalent in rems is equal to the absorbed dose in rads multiplied
by the quality factor (1 rem=0.01 sievert).
4. Sievert (Sv) is the SI unit of any of the quantities expressed as dose eq
uivalent. The dose equivalent in sieverts is equal to the absorbed dose in... 阅读全帖 |
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c***c
发帖数: 21374 | 27 今天看这个，觉得放射性元素辐射这个东西实在可怕
http://www.youtube.com/watch?v=2G422z8pDn4
This is the sequence of the nuclear criticality accident from "Fat Man and
Little Boy" with John Cusack. This storyline was based on two real accidents
that occurred early in the US's nuclear weapons program that killed two
brilliant scientists.
What happened was that he was checking the neutron flux, keeping the two
halves of the plutonium core seperated with a screwdriver. The blocks around
the sphere are tungsten carbide, a ne... 阅读全帖 |
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s*****V
发帖数: 21731 | 28 不光是奇点，就是EVENT HORIZON也是简介证据， 像下面这样的
The Rates of type I X-ray Bursts from Transients Observed with RXTE:
Evidence for Black Hole Event Horizons
Ronald A. Remillard, Dacheng Lin, Randall L.Cooper, Ramesh Narayan
http://arxiv.org/abs/astro-ph/0509758
Abstract: We measure the rates of type I X-ray bursts, as a function of the
bolometric luminosity, from a likely complete sample of 37 non-pulsing
transients (1996-2004). Our goals are to test the burst model for neutron
stars and to investigate wheth... 阅读全帖 |
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F******M
发帖数: 98 | 29 实验凝聚态物理方向PhD，目前在纳米材料方向做博后。很希望能在一年后走eb1b申请
绿卡。方向是强关联电子体系
、热电半导体
铁基超导的生长，表征。精通各项实验分析: single crytal growth，PPMS, MPMS,
TEM, SEM/EDS, TGA, DSC, Powder Neutron & X-ray Scattering, Four-circle
Single Crystal Neutron Diffraction, Triple axis spectroscopy, Neutron
Reflectometry, NMR.
已有多次次审稿经验，各位有相关文章的兄弟姐妹请推荐给我吧。保证认真对待每篇文
章，绝不轻易据稿。只要是在我研究范围之类的稿件，必定给出详细的修改意见以及建
议。非常感谢各位！ |
|
F******M
发帖数: 98 | 30 实验凝聚态物理方向PhD，目前在纳米材料方向做博后。很希望能在一年后走eb1b申请
绿卡。方向是强关联电子体系
、热电半导体
铁基超导的生长，表征。精通各项实验分析: single crytal growth，PPMS, MPMS,
TEM, SEM/EDS, TGA, DSC, Powder Neutron & X-ray Scattering, Four-circle
Single Crystal Neutron Diffraction, Triple axis spectroscopy, Neutron
Reflectometry, NMR.
已有多次次审稿经验，各位有相关文章的兄弟姐妹请推荐给我吧。保证认真对待每篇文
章，绝不轻易据稿。只要是在我研究范围之类的稿件，必定给出详细的修改意见以及建
议。非常感谢各位！ |
|
g********d
发帖数: 19244 | 31 http://en.wikipedia.org/wiki/Criticality_accident
A criticality accident occurs when a critical reaction is achieved
unintentionally. Although dangerous, typical criticality accidents cannot
reproduce the design conditions of a fission bomb, so nuclear explosions do
not occur.
excursion: 瞬发临界
无论反应堆爆炸的起因是什么 结果都是overheating 一回路蒸汽压力过高 撑破管道
你这半吊子 以后出门千万别说自己是核工的 只能给核工丢脸
有什么不同？我都在美国学的， 有时不知道怎么翻译成中文。
but， yes, it released a surge of neutrons and increases the core power and
it resulted another explosi... 阅读全帖 |
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s*****t
发帖数: 1994 | 32 The Planet, the White Dwarf, and the Neutron Star
Credit: H. Richer (Univ. British Columbia), et al. NASA, NOAO
Explanation: A planet, a white dwarf, and a neutron star orbit each other in the giant
globular star cluster M4, some 5,600 light-years away. The most visible member of the trio is
the white dwarf star, indicated above in an image from the Hubble Space Telescope, while the
neutron star is detected at radio frequencies as a pulsar. A third body was known to be present
in the p |
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o********e
发帖数: 34 | 33 Postdoctoral Research Associate
Neutron Scattering Sciences Division
Research Accelerator Division
Oak Ridge National Laboratory Oak Ridge, Tennessee
Project Description:
Works closely with the scientists at the SNS on developing the novel spin-
encoding real-space neutron scattering technique and conducting active
research related with soft-condensed matter materials using the state-of-the
-art neutron scattering instruments available in national labs. In addition,
the candidate will have chanc |
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s*****t
发帖数: 1994 | 34 The Planet, the White Dwarf, and the Neutron Star
Credit: H. Richer (Univ. British Columbia), et al. NASA, NOAO
Explanation: A planet, a white dwarf, and a neutron star orbit each other in the giant
globular star cluster M4, some 5,600 light-years away. The most visible member of the trio is
the white dwarf star, indicated above in an image from the Hubble Space Telescope, while the
neutron star is detected at radio frequencies as a pulsar. A third body was known to be present
in the p |
|
m****n
发帖数: 226 | 35 这次日本福岛核电站事故原来叫作"China Syndrome"
China Syndrome
The 'China Syndrome' refers to a possible result of the catastrophic
meltdown of a nuclear reactor. Also called a loss of coolant accident, the
scenario begins when something causes the coolant level in a reactor vessel
to drop, uncovering part—or all—of the fuel rod assemblies. Even if the
nuclear chain reaction has been stopped through use of control rods or other
devices, the fuel continues to produce significant residual heat for some
time due t... 阅读全帖 |
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n*****1
发帖数: 1329 | 36 On May 21, 1946, with seven other colleagues watching, Slotin performed an
experiment that involved the creation of one of the first steps of a fission
reaction by placing two half-spheres of beryllium (a neutron reflector)
around a plutonium core. The experiment used the same 6.2-kilogram (13.7 lb)
plutonium core that had irradiated Harry K. Daghlian, Jr., later called the
"Demon core" for its role in the two accidents. Slotin grasped the upper
beryllium hemisphere with his left hand through a ... 阅读全帖 |
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b***y
发帖数: 14281 | 37 No. The search include his early works up to 1978. Here is the same list
sorted by year.
1) The Influence of Gravitation on the Vacuum State.
By Li-Zhi Fang.
Acta Phys. Sinica 27 ( 1978) 181-18.
2) THE STRUCTURE AND STABILITY OF THE ABNORMAL NEUTRON STAR.
By Li-Zhi Fang, Qin-Yue Qu, Zhen-Ru Wang, Tan Lu, Liao-Fu Luo.
Sci.Sin.22:187-198,1979.
3) Some Recent Developments in Astrophysics. (Talk).
By Li-Zhi Fang, A. Qadir, R. Ruffini.
In *Nathiagali 1980, Proceedings, Physics and Contemporary Needs... 阅读全帖 |
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d*b
发帖数: 21830 | 38 你知道重离子怎么产生的么？事实上neutron activation产生的heavey ion都是低能量
的，只有neutron才是高能量的。动量守恒知道么？ |
|
s*****V
发帖数: 21731 | 39 http://news.sciencemag.org/physics/2014/10/z-machine-makes-prog
The Sandia researchers reported this week in Physical Review Letters that
they had heated the plasma to about 35 million degrees Celsius and detected
about 2 trillion neutrons coming from each shot. (One reaction of fusing two
deuteriums produces helium-3 and a neutron.) Although the result shows that
a substantial number of reactions is taking place—100 times as many as the
team achieved a year ago—the group will need to produce 10... 阅读全帖 |
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d******n
发帖数: 3836 | 40 【 以下文字转载自 LeisureTime 讨论区 】
发信人: dirtyman (得体男，人称脏生), 信区: LeisureTime
标 题: 这篇科幻看起来不错！《龙蛋》（转载）
发信站: BBS 未名空间站 (Thu Jun 9 16:00:50 2016, 美东)
中子星确实会冷却。冷到合适的温度，还可能孕育出生命，甚至文明。
图片来自The Largest Neutron Star in Existence
新生的中子星温度在约1千亿到1万亿度之间。令人发指的高温来自它的前身——恒星热
聚变产生的巨大能量。然而，作为恒星的残骸，中子星本身并没有补充能量的机制，
反而会释放出大量的中微子，带走它的能量。这种无源之水很快就会走向干涸。在短
短数年之间，它的温度就会下降到百万度左右。这时，它仍然以X射线的方式向太空释
放能量，让自己的温度继续下降。
从诞生之初，中子星就带有很高的自转速度，一般在每秒钟数圈的范围内。自转能量
同样来自它的前身恒星。恒星虽然转速很慢，但是在大量恒星物质收缩成中子星以
后，角动量守恒原理就会大大增加自转速度。这个过程和旋转的滑冰运动员把双臂收
回... 阅读全帖 |
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r*******e
发帖数: 680 | 41 if a missile carries nuke, it does not need to actually hit the target or
precisely hit anything. Nuke has a killing zone of miles. as long as it
survives to re-entry, that is the end of whole fleet of the carrier
underneath.
the neutron nuke would be better, which kills all electronics and spares all
lives. one neutron nuke will brick all ship and aircraft but kills no
people. Thus it could end the war without bloodshed.
So, aircraft carriers have no real meaningful threat to a nuclear power su... 阅读全帖 |
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N*****P
发帖数: 216 | 42 Chernobyl 是已经炸完了封,它的 moderator（用来slow down neutrons) 是 graphite
（想象一下煤炭）,高温的燃料和graphite 一起爆炸了，封是为了掩埋这些暴露在空
中的radioactive material. 基本就是核弹爆炸了，你做事后处理，清理ground，希望
这个地方多少年后还可以住人。
福岛还没有到燃料棒爆炸的境地，所作的工作是让里面继续在反应的neutron被吸收，
同时把热导出来，谁是最简单且有效的方法。这是为什么核电站都在水边的原因。
现在所谓封堆也只能更多的注水，水泥效率太慢，而且并不那么导热。 |
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o********e
发帖数: 34 | 43 【 以下文字转载自 Physics 讨论区 】
发信人: olivertree (Life is good), 信区: Physics
标 题: Postdoc openning at SNS, Oak Ridge National Lab
发信站: BBS 未名空间站 (Thu Dec 11 21:16:49 2008)
Postdoctoral Research Associate
Neutron Scattering Sciences Division
Research Accelerator Division
Oak Ridge National Laboratory Oak Ridge, Tennessee
Project Description:
Works closely with the scientists at the SNS on developing the novel spin-
encoding real-space neutron scattering technique and conducting active
research related w |
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a**i
发帖数: 2 | 44 The Neutron Scattering Science Division at Oak Ridge National Laboratory
seeks to fill a postdoctoral research associate position in neutron
scattering studies of soft-condensed matter systems. A PhD or equivalent
degree in physics, materials science, chemistry or related field is required
. The successful candidate is expected to have a background and experience
in soft matter studies and proficiency with applications of scattering
methods to structural/dynamical characterization.
The candidate |
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k******6
发帖数: 7 | 45 Project Description
The Functional Hybrid Nanostructures group at the Center for Nanophase
Materials Sciences (CNMS) at Oak Ridge National Laboratory is seeking to
fill a postdoctoral research position in the area of thin film organic
electronics fabrication and optoelectronic properties characterization. This
position will provide a unique opportunity to perform research on the
structure–function relationships of new classes of optoelectronic organic
semiconductor materials, correlating fundame... 阅读全帖 |
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J***s
发帖数: 232 | 46 浙大学生为给浙大贴金真是无所不用其极啊，浙大发不了NS就起劲黑NS。我给你随便举
几个例子，你说下面哪篇文章上不了教科书？
J. Chadwick (1932). "Possible existence of a neutron". Nature 129 (3252):
312.
L. Meitner and O. R. Frisch (1939). "Disintegration of uranium by neutrons:
a new type of nuclear reaction". Nature 143 (3615): 239–240.
J. D. Watson and F. H. C. Crick (1953). "Molecular structure of Nucleic
Acids: A structure for deoxyribose nucleic acid". Nature 171 (4356): 737–
738.
J. C. Kendrew, G. Bodo, H. M. Dintzis, R. G. Parrish, H. Wyckoff and D.... 阅读全帖 |
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b*****l
发帖数: 298 | 48 http://www.chem.uci.edu/~gemiller/reactor.html
这个东西跟那个电厂啥的不是一个级别的吧.
有看得懂的同学画个可能需要的疏散范围吧
The reactor is a 250 kilowatt steady-state power Mark I TRIGA reactor built
by General Atomics. Pulsing is possible to about 1000 megawatts if needed.
TRIGA reactors are water and zirconium hydride moderated to be especially
safe for training and research purposes. Fuel is uranium enriched to 20% in
U-235. The reactor first became critical in November 1969. The facility
specializes in neutron activation analy... 阅读全帖 |
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d******n
发帖数: 3836 | 49 中子星确实会冷却。冷到合适的温度，还可能孕育出生命，甚至文明。
图片来自The Largest Neutron Star in Existence
新生的中子星温度在约1千亿到1万亿度之间。令人发指的高温来自它的前身——恒星热
聚变产生的巨大能量。然而，作为恒星的残骸，中子星本身并没有补充能量的机制，
反而会释放出大量的中微子，带走它的能量。这种无源之水很快就会走向干涸。在短
短数年之间，它的温度就会下降到百万度左右。这时，它仍然以X射线的方式向太空释
放能量，让自己的温度继续下降。
从诞生之初，中子星就带有很高的自转速度，一般在每秒钟数圈的范围内。自转能量
同样来自它的前身恒星。恒星虽然转速很慢，但是在大量恒星物质收缩成中子星以
后，角动量守恒原理就会大大增加自转速度。这个过程和旋转的滑冰运动员把双臂收
回后，转速会提高是一个道理。
图片来自
http://osfundamentosdafisica.blogspot.sg/2013_01_01_archive.html
随着中子星高速旋转的磁场也是释放能量的渠道之一，它会逐渐降低中子星的自转速
度。当中子星速度降低时，它的形状也会相... 阅读全帖 |
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n******y
发帖数: 126 | 50 Two atoms walked on a street. One said to another "I think I lost an
electron". The other asked "are you sure?". The first said "I'm positive".
A neutron went into a bar and asked the bartender "how much is a beer?" The
bartender looked at the neutron up and down and said "for you, no charge." |
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