c**********a
发帖数: 6 | 1 Dendrimer-based dispersant have great performance.
To lead the solid matter such as pigment into a liquid medium, a high
mechanical strength is necessary, traditionally, use dispersants to deal
these substances, mainly related surfactants. In addition, the dispersed
solid material tends to re-coalescence and flocculate the entire system,
current disadvantage of the products is that viscosity is limited to lower
with highly filled colored dispersion system. Dendritic dispersant has
superior dispe... 阅读全帖 |
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m********e
发帖数: 177 | 2 这个问题困扰了我很久，呵呵
做Column试验的时候，一般要先run一下tracer，从tracer的break through curve（
BTC）来fit一个dispersivity。理想情况下，因为tracer不会有任何反应，所以在1个
pore volume（PV）的时候BTC上对应的C/C0应该是0.5。但是由于试验操作上总会有一
点误差，尤其是pore volume，porosity以及pore velocity(v)的测量和确定，所以最
终BTC上C/C0=0.5对应的PV一般很少刚好在1PV上，多数情况下会大于1PV。
以前一位师兄告诉我，可以认为pore volume测得不准，通过调整pore volume使得C/C0
=0.5对应在1PV来得到相应的porosity和linear velocity，然后来fit dispersivity。
有的人同时fit dispersivity和velocity，这样其实就是默认pore volume和porosity
测得不准。也看到有的人在paper上发表的数据是同时fit dispersivity和retardation |
|
n*******n
发帖数: 407 | 3 Let X be a Poisson variable with parameter λ with a probability mass
function, f(k), where k = 0, 1, 2 … We know the index of log-concavity is
the function rf(k) = f(k)^2/(f(k-1)f(k+1) = (k+1)/k>1. So, Poisson is log-
concave.
Many books have: "The random variable Y is dispersive if, and only if, Y has
a logconcave density."
Poisson variable is discrete. Do we have: A Poisson variable X is dispersive?
Or, more specifically, let X be a Poisson variable with parameter λ1 with a
probability mass fu... 阅读全帖 |
|
n*******n
发帖数: 407 | 4 Dispersive order: Let X and Y be random variables with quantile functions F-
1 and G-1 respectively. If F-1(b)- F-1(a) <= G-1(b)- G-1(a) whenever 0
< 1; then X is said to be smaller than Y in the dispersive order. |
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T*******x
发帖数: 8565 | 5 从dispersive order的定义看，泊松分布的lambda越大，应该越dispersive。
F-
|
|
m********h
发帖数: 405 | 6 【 以下文字转载自 Chemistry 讨论区 】
发信人: mitbbsfish (老六), 信区: Chemistry
标 题: 关于石油dispersant
发信站: BBS 未名空间站 (Sat May 15 12:40:39 2010, 美东)
在想那些dispersant把墨西哥湾区的石油都分散成小油滴，表面上好象污染消除了，可
是那些小油滴还在海水里，有多少鱼会吞下去，留在胃里，中毒啊。哪怕死不了，将来
我们钓上那些肚子里有石油的鱼虾 是不是也有危害？
大家说说是不是比宏观的污染更厉害？ |
|
|
a***h
发帖数: 1222 | 8 The same question have troubled me for some time. Later I realized that
dispersivity is just an adjustable parameter in the model for most of the
cases. It is not really an intrinsic property of the porous media. Actually,
if you adjust the column length, say, from 5 cm to 10 cm, you will get a
different dispersivity value.
As for pore volume, there are different ways to measure it and express it.
You can measure it either by mass or by time (assume steady flow). Some
times there are discrepanci |
|
c*****t
发帖数: 520 | 9 我最近粗看了些和dispersive equations相关的内容，对这方面的研究颇为疑惑，想请
了解这个领域的朋友指教。
我看的内容，包括water waves, Schrodinger equations, solitons, inverse
scattering等课题，应该算是和dispersive equations的研究相关吧。
比方说，我在MIT Open Course Ware看到名为Wave Propagation的课程，浏览了讲义。
ocw.mit.edu/OcwWeb/Mechanical-Engineering/2-062JFall-2006/CourseHome/index.
htm
从编号看，这门课是Civil and Environmental Engineering，Mechanical
Engineering 以及Mathematics 这3 个系合开的。涉及了water waves 之类的课题。
另外我看了Mark J. Ablowitz的几本关于solitons等课题的书。
http://amath.colorado.edu/~markjab/boo |
|
c*****t
发帖数: 520 | 10 抱歉，我似乎没有把意思表达清楚。
我想问：以MIT 为例，数学系开的名为Wave Propagation的课程，和系里面研究
dispersive equations的教授的工作，似乎差得很远。
是不是要去学习dispersive equations，即便PDE论文的题目是关于具体的方程的，例
如Schrodinger equations ，Water waves 等课题，也是和物理背景没有什么关系，只
是和Fourier transform 等分析技巧有关的？看应用数学方面的专著，例如上述MIT 课
程讲义，以及Mark J. Ablowitz的书，并不能起到什么帮助？
请了解的朋友指教。非常感谢。 |
|
G***G
发帖数: 16778 | 11 some websites gave a heatmap of the energy dispersion of an earthquake?
how can scientist estimate that? Is that accurate? |
|
S********0
发帖数: 67 | 12 I am going to submit my manuscript in the areas related to pharmaceutics,
crystallization, solid dispersion and polymer. I need to put the suggested
reviews during the submission. Anyone interested? Please send me your name,
email, institution and expertise.
Thanks |
|
j****g
发帖数: 166 | 13 disperse dyes in polymer matrix polymer-penetrant systems
有兴趣者，请将CV及个人信息发至9717【艾特】outlook。com |
|
d*******n
发帖数: 1566 | 14 有没有人读过这篇paper！
http://prb.aps.org/abstract/PRB/v58/i19/p12899_1
Phys. Rev. B 58, 12899–12907 (1998)
Phonon dispersion and Raman scattering in hexagonal GaN and AlN
Abstract
References
Citing Articles (122)
Download: PDF (182 kB) Buy this article Export: BibTeX or EndNote (RIS)
V. Yu. Davydov*, Yu. E. Kitaev, I. N. Goncharuk, and A. N. Smirnov
Ioffe Physical Technical Institute, St. Petersburg 194021, Russia
J. Graul, O. Semchinova, and D. Uffmann
LFI Universitat Hannover, Schneiderberg 32, 30167 |
|
m********h
发帖数: 405 | 15 在想那些dispersant把墨西哥湾区的石油都分散成小油滴，表面上好象污染消除了，可
是那些小油滴还在海水里，有多少鱼会吞下去，留在胃里，中毒啊。哪怕死不了，将来
我们钓上那些肚子里有石油的鱼虾 是不是也有危害？
大家说说是不是比宏观的污染更厉害？ |
|
r******0
发帖数: 2753 | 16 让BP换个不那么毒的dispersant而已。
spill
toxic |
|
c*s
发帖数: 2145 | 17 【 以下文字转载自 Chemistry 讨论区 】
发信人: cds (呼呼猪-嘿嘿， 老板， 来盘泡菜), 信区: Chemistry
标 题: how to disperse carbon nanotube?
发信站: BBS 未名空间站 (Sat Oct 1 21:14:29 2005)
in whatever solvent?
how to seperate them from the bundles?
3ks |
|
S*****n
发帖数: 6055 | 18 DMF ultrasonication
even ethanol or water under ultrasonication can sepaprate CNTs bundles
However，dispersion in DMF can last long after the ultrasonication process |
|
k****n
发帖数: 162 | 19 【 以下文字转载自 Chemistry 讨论区 】
发信人: kigeon (你会用D70么), 信区: Chemistry
标 题: 求助金粒子有机相中dispersion
发信站: BBS 未名空间站 (Thu Sep 3 16:25:49 2009, 美东)
不是纳米大小的，这个文献ms有很多。700－800 nm 直径的怎么修饰表面能使粒子分散
在有机溶剂中呢，比如toluene？多谢了！ |
|
f***r
发帖数: 344 | 20 经过各种处理后，比如超声微波强酸等，已经可以比较好的disperse，但同时破坏CNT
结构了 |
|
d*******n
发帖数: 1566 | 21 有没有人读过这篇paper，
期末考试是要将这一篇paper，无耐不是我的背景，
应该是比较经典的文章，如果有人熟悉可以帮忙一下感谢万分！
谢谢
（站内信）
http://prb.aps.org/abstract/PRB/v58/i19/p12899_1
Phys. Rev. B 58, 12899–12907 (1998)
Phonon dispersion and Raman scattering in hexagonal GaN and AlN
Abstract
References
Citing Articles (122)
Download: PDF (182 kB) Buy this article Export: BibTeX or EndNote (RIS)
V. Yu. Davydov*, Yu. E. Kitaev, I. N. Goncharuk, and A. N. Smirnov
Ioffe Physical Technical Institute, St. Petersburg 194021, Russia
J. Graul, O. Semchinova, |
|
p****u
发帖数: 2596 | 22 比如top ５００股票的daily return dispersion，怎么算？ 是不时就是方差？ 谢谢 |
|
s******a
发帖数: 184 | 23 在一些材料中看到，在R 中用GLM 做完model fitting 后，用residual deviance 去除
dispersion parameter。 这个得出的指标是什么？ |
|
l*********s
发帖数: 5409 | 24 sounds like dispersion estimate or scaled deviance. |
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m******7
发帖数: 11 | 25 有一点不能苟同，我认为dispersion绝对不是diffusion的同义词，二者差别较大，其
实dispersion与convection的含义倒是有点接近。diffusion一般翻译成扩散，主要指
分子扩散，比如催化剂内部的气体扩散。而dispersion则一般翻译成弥散，扩散。这个
单词一般不用于气体在催化剂颗粒内部的扩散，以及溶质在溶剂中的扩散，以气固流化
床为例，气体在整个反应器尺度范围内的组分扩散（弥散）经常用dispersion来形容，
而这种dispersion在很大程度上包括了对流扩散，它主要是指气体组分在反应容器内的
迁移，而一旦气体进入固体，就要用diffusion而绝对不能用dispersion了 |
|
p*********e
发帖数: 32207 | 26 ☆─────────────────────────────────────☆
yeemartin (猪头) 于 (Mon Aug 17 05:10:38 2009, 美东) 提到:
看了一篇的文章
有解释为啥Shell Rotella T、Mobil Delvac这些heavy duty diesel oil的Used oil
analysis结果都很突出的原因，普通engine oil是S certification，例如SJ、SM。商
用truck engine oil是C certification， 目前是CI、CJ。C的additive package比S的
牛x很多，但有可能会不兼容乘用车上的catalytic converter。
我的G35目前就在用Shell Rotella T，摩托车下次换油也准备用这个。mobil的
synthetic motorcycle oil 1 quart 12刀，受不了。
Commercial (Diesel) Oil
The additive packages for C (commercial) certification... 阅读全帖 |
|
c****o
发帖数: 2071 | 27 Chinese, Russian media turn criticisms back on US
BEIJING (AP) — Chinese and Russian state media have seized on the U.S.
police shooting of an unarmed black 18-year-old and ensuing protests to fire
back at Washington's criticisms of their own governments, portraying the
United States as a land of inequality and brutal police tactics.
The violence in the St. Louis, Missouri, suburb of Ferguson comes amid
tensions between the U.S. and Russia over Ukraine, as well as friction
between Washington and... 阅读全帖 |
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h*******d
发帖数: 8 | 28 Center of Atmospheric Science
University of Illinois at Urbana-Champaign
This position is aimed to improve the capabilities of existing atmospheric
dispersion models to stimulate local and regional pollen and seed dispersion
, deposition, and outcrossing. Models will be converted to an online tool so
stakeholders can easily access and use.
Duties and Responsibilities: Measure and model plants atmospheric gene flow
, including pollen and seed release, dispersion, deposition and outcrossing.
An... 阅读全帖 |
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h*******d
发帖数: 8 | 29 Center of Atmospheric Science
University of Illinois at Urbana-Champaign
This position is aimed to improve the capabilities of existing atmospheric
dispersion models to stimulate local and regional pollen and seed dispersion
, deposition, and outcrossing. Models will be converted to an online tool so
stakeholders can easily access and use.
Duties and Responsibilities: Measure and model plants atmospheric gene flow
, including pollen and seed release, dispersion, deposition and outcrossing.
An... 阅读全帖 |
|
y*****a
发帖数: 580 | 30 I would agree on 我认为dispersion绝对不是diffusion的同义词，二者差别较大,
but disagree on 其实dispersion与convection的含义倒是有点接近. convetion and
diffusion/ advection and dispersion should be the conjugate terms.
As such it is named CDE (convetion-diffusion equation) or ADE(advection-
dispersion equation). Convetion/diffusion names a hypothesis. Advection/
dispersion names a net/macroscopic phenomenon.
Actually, it is a very good question and most people have no idea of the
difference between them. It is one of the m |
|
c*********o
发帖数: 1734 | 31 I will recommend the first three responds with the right background to the
editor.
There is no guarantee you will be picked by the editor.
Send email to c*********[email protected] with the following information:
You official name
Your degree
Your business email address
You business title
And brief introduction of your background.
Most important: register with EJPS as a reviewer with your business email
address before you send me email
I will not recommend you if you miss any of above.
"Solid self - e... 阅读全帖 |
|
t********y
发帖数: 21 | 32 曝光模式
P：（program AE）程序自动曝光
A：（aperture priority）光圈优先自动曝光
S：（shutter priority）快门速度优先自动曝光
M：（manual）手动曝光
测光模式
CW：（centre-weighted average）中央重点加权平均测光
SP：（spot metering）点测光
MS：（multi-segment）多分区测光
闪光模式
A： （auto flash）自动闪光
RE：（red-eye reduction）防红眼闪光
SL：（slow syn.flash）慢速同步
OF：（OFF）关闭
FI：（fill-in flash）填充式闪光
RF：（rear flash sync）后帘同步
WR：（wireless/remote flash）无线/遥控
E-TTL：（evaluated TTL）评估式TTL
取景器
镜头标识
AD:（anomalous dispersion）异常色散
AE：（auto exposure）自动曝光
AF：（autofocus）自动对焦
AF-I：（AF nikkor）尼康内置马达的镜头
AF-S... 阅读全帖 |
|
l*****7
发帖数: 8463 | 33 44人被捕, 看看美国警察的执法
Dozens arrested at Massachusetts 'Blarney Blowout'
UMass Amherst students, police in riot gear scuffle in Blarney Blowout melee
http://t.co/sJE6ttY9q0 http://t.co/YSR1ZuRhpH
AMHERST, Mass. (AP) - An early St. Patrick's Day celebration around the
University of Massachusetts' flagship campus known as "Blarney Blowout" spun
out of control Saturday as police officers in riot gear arrested more than
40 people while dispersing massive crowds, including unruly students
throwing beer ca... 阅读全帖 |
|
发帖数: 1 | 34 Central Americans vow to continue as Mexico disperses 'caravan'
Mexico to issue one-year visas to most vulnerable, ask others on caravan
that caught Trump's ire to leave in 20 days.
by Maya Averbuch
9 hours ago
Central Americans vow to continue as Mexico disperses 'caravan'
Central American migrants travelling with the caravan march to call for
migrant rights and protest the policies of US President Donald Trump, in
Matias Romero, Mexico [Felix Marquez/AP Photo] [Daylife]
more on US-Mexico borde... 阅读全帖 |
|
p***y
发帖数: 18037 | 35 Taiwanese linguist races to save dying language
Photo: AP Children learn their tribal dialect in their aboriginal mountain
village of Piuma, southern Taiwan. In a race against time, a dedicated
Taiwanese linguist is trying to save the historically important aboriginal
dialect of Kanakanvu, spoken by only 10 people, from extinction.
Photo: AP Eighty-year-old Mu'u Ka'angena speaks to a graduate student,
documenting his dying tribal language in the aboriginal Kanakanvu mountain
village of Dakanua, ... 阅读全帖 |
|
B********e
发帖数: 19317 | 36 【 以下文字转载自 WaterWorld 讨论区 】
发信人: ruomu (ruomu), 信区: WaterWorld
标 题: 一个学长天天玩dota 结果GRE接近满分 让你见识下。。。
发信站: BBS 未名空间站 (Fri Apr 1 10:58:57 2011, 美东)
总的来说，DoTA是一个文化包容性很强的游戏，而且DOTA中文版翻译的还是非常非常好
的~~~
（既然这么多人看。。lz顺征人交流魔兽对战，是1v1对战喔）
后文会出现的一些常用缩写：
War3:warcraft 3 魔兽争霸3
RA：red alert 红色警戒系列
SC: star craft 星际争霸
CoD:call of duty 使命召唤
还有一些游戏的名称在文中会有注释。
好了，正文：
关于Dota和一些游戏中的GRE词汇
A字头
Abaddon ：DOTA中地狱领主的名字。本意为地狱，恶魔。是圣经里的亚玻伦 (地狱的
使者)。
abomination：war3中的憎恶。abominate痛恨，憎恶。
aegis：immortal aeg... 阅读全帖 |
|
r***u
发帖数: 1272 | 37 总的来说，DoTA是一个文化包容性很强的游戏，而且DOTA中文版翻译的还是非常非常好
的~~~
（既然这么多人看。。lz顺征人交流魔兽对战，是1v1对战喔）
后文会出现的一些常用缩写：
War3:warcraft 3 魔兽争霸3
RA：red alert 红色警戒系列
SC: star craft 星际争霸
CoD:call of duty 使命召唤
还有一些游戏的名称在文中会有注释。
好了，正文：
关于Dota和一些游戏中的GRE词汇
A字头
Abaddon ：DOTA中地狱领主的名字。本意为地狱，恶魔。是圣经里的亚玻伦 (地狱的
使者)。
abomination：war3中的憎恶。abominate痛恨，憎恶。
aegis：immortal aegis 不朽盾，同时aegis是汉化版的作者。在RA2中也有神盾巡洋
舰 AEGIS Cruiser。
acolyte：侍僧,教士的助手。war3中Undead的农民。
alacrity：blade of alacrity 欢欣之刃。alacrity还有敏捷之意，所以它加敏捷属
性就... 阅读全帖 |
|
c**i
发帖数: 6973 | 38 Gautam Naik, Clues to Man's First Migration; Genes from Australia point to
several waves African dispersal, not just one. Wall Street Journal, Sept 23,
2011.
http://online.wsj.com/article/SB1000142405
3111904563904576586783498941802.html
My comment:
(a) If you can not read the report (because WSJ restricts how many a person
can view its article for free), you can read
Ann Gibbons, Aboriginal Genome Shows Two-Wave Settlement of Asia. Science,
333: 1689-1691 (Sept 23, 2011).
http://www.sciencemag.... 阅读全帖 |
|
r***n
发帖数: 579 | 39 dispersion 是diffusion 和convection 共同作用的结果。比如taylor dispersion中
，diffusion越大，dispersion 越小。 |
|
c*u
发帖数: 916 | 40 Of course dispersion will affect a 30 nm bandwidth pulse in 4 m of fiber,
especially if the center wavelength is not 1310 nm or it's specified
zero-dispersion wavelength. 30 nm is very wide bandwidth for most
applications. Let's say dispersion 5 ps/nm/km, then for 4 m and 30 nm, it
is almost 0.6 ps. The bandwidth is narrowed to almost 6 nm.
On the other hand, it's very rare that a fiber can't support 30 nm
bandwidth. |
|
k*******n
发帖数: 2399 | 41 I have been working on the dispersion and characterization of synthesized
SWNTs for a couple of monthes. In most cases, surfactant aided dispersion
by using water as solvent will give better signals compared with using organic
solvents like DMF, DMA. MWNT should not give appreciable signals, but DWNTs do.
Surfactants good for dispersion are DOC, sodium cholate, SDS, et. al.. If
you still did not get nice spectra, your SWNTs might not be of high purity.
For some SWNTs, the remaining impurities li |
|
i*****s
发帖数: 15215 | 42 Most Instagram fans will take a photo of their mates on a city street, or
perhaps snap a nice bit of scenery to add to their photo library.But 57-year
-old Martin Harvey decided to go a little further afield - Kenya to be exact
- and get the photograph of a lifetime.In his amazing shot, scores of pink
flamingos - all facing to the right like an amassed army - are captured
beneath a brooding sky. More of their comrades fly overhead, and the whole
image is saturated in rich colour that gives it an... 阅读全帖 |
|
n*2
发帖数: 19062 | 43 ☆─────────────────────────────────────☆
IcyLi (IcyLi) 于 (Sat Aug 25 12:30:53 2012, 美东) 提到:
最开始用的题目叫【实况，图】偷窥另类的XOXO运动。偷窥，是因为要歪着脖子从一个
窄缝里看。另类，是因为不是人类，是蜘蛛。
试图用图片记载cellar spider蜘蛛求爱、前戏、XOXO，怀孕生子的全过程，又是还会
穿插家里家外看到的一些别的蜘蛛（甚至别的小动物）的照片。还有几张网上找来的
蜘蛛照片。
从8/25/12开始，每天更新照片，到9/24/12结束，历时30天。图省事的话看本楼就行。
有空闲可逐层爬楼，里面还有好多亮点。
8/25
家里比较乱，成了蜘蛛的乐园。几个常驻蜘蛛我也了然于胸。今天突然发现一个角落里
位于两个纸箱空隙间的母蜘蛛有客，不用想，肯定是有人上门求爱了。
现在还是前戏阶段，雄蜘蛛现在还在试探阶段，一靠近就被母的给赶跑了。公蜘蛛也算
知趣，非常小心的靠近，运气不好就有可能被吃掉。
是那种腿很细长的那种蜘蛛，这边叫cellar spider。蜘蛛的周边很乱，包括别的昆虫
的... 阅读全帖 |
|
p**********t
发帖数: 2636 | 44 Hanna是做动物行为的，对植物的讨论不是很多。实际上parent-offspring conflict对
被子植物的起源有很好的解释。被子植物与裸子植物主要的区别就是被子植物的种子被
母系的组织包裹。对parent来说，子代只要能活下去，跑越远越好，不要跟自己竞争；
对子代来说，从parent那里吸收营养越多，越有利于成活。裸子植物的seed dispersal
很单一，而被子植物的seed dispersal strategy就多样很多，也许就是与母系组织参
与seed dispersal，不同的利益取向有关
but |
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p**********d
发帖数: 7918 | 45 China calls for domestic unrest to be defused
By Chris Buckley
Mon Feb 21, 7:37 am ET
BEIJING (Reuters) – China must find new ways to defuse unrest, the domestic
security chief said,
underscoring Beijing's anxiety about control after police quashed calls for
gatherings inspired by uprisings
in the Middle East.
A Foreign Ministry official separately blamed the political violence
sweeping the Middle East on too-slow
growth and stunted efforts at reform.
Zhou Yongkang, the ruling Communist Party's ... 阅读全帖 |
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a****1
发帖数: 654 | 46 Report: 'Dirty bomb' parts found in slain man's home
By Walter Griffin
Posted Feb. 10, 2009, at 10:22 p.m.
BELFAST, Maine — James G. Cummings, who police say was shot to death by his
wife two months ago, allegedly had a cache of radioactive materials in his
home suitable for building a “dirty bomb.”
According to an FBI field intelligence report from the Washington Regional
Threat and Analysis Center posted online by WikiLeaks, an organization that
posts leaked documents, an investigation into th... 阅读全帖 |
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x******g
发帖数: 33885 | 47 这份是89年的六四前夕的电报：（很有历史研究的意义啊）
http://www.wikileaks.org/cable/1989/04/89BEIJING10642.html
PRO-DEMOCRACY DEMONSTRATORS FLOOD TIANANMEN
SQUARE IN SECOND NIGHT OF DEMONSTRATIONS
¶1. CONFIDENTIAL - ENTIRE TEXT.
¶2. SUMMARY: THOUSANDS OF STUDENTS FROM BEIJING
UNIVERSITIES FLOODED TIANANMEN SQUARE IN CENTRAL
BEIJING FOR A SECOND NIGHT ON APRIL 18. THEY CROWDED
AROUND THE BASE OF THE MARTYRS MONUMENT AT THE CENTER
OF THE SQUARE CHANTING PRO-DEMOCRACY SLOGANS AND
SINGING PATRIOTIC SONGS. TEN... 阅读全帖 |
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l*****7
发帖数: 8463 | 48 http://www.gwu.edu/~nsarchiv/NSAEBB/NSAEBB80/
home | about | documents | news | publications | FOIA | research |
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Iraq and Weapons of Mass Destruction
National Security Archive Electronic Briefing Book No. 80
Updated - February 11, 2004
Edited by Jeffrey Richelson
Originally posted December 20, 2002
Previously updated February 26, 2003
Documents - Press release - Further reading
Between Iraq's invasion of Kuwait in August 1990, and the commencement of... 阅读全帖 |
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