A*V
发帖数: 3528 | 1 发信人: gezhi89 (zhonda), 信区: Living
标 题: Re: 请教Walkout Basement的优缺点？
发信站: BBS 未名空间站 (Thu Mar 4 02:16:28 2010, 美东)
I have dug a water well and natural gas well (which is the main reason I
choose this land).
I also have a large pond filled with water now.
I do not use public water or sewer (I am just too far out for them to reach)
I am hooked up to electric grid, but most of my electricity is generated by
micro turbine and a few wind turbines.
According to my calculations, I have enough gas to las |
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w***f
发帖数: 903 | 2 Anderson 能在Utah State 成功是方方面面的条件都成熟的结果。他来之前， Utah
State一般是每年1胜。所以他前两年每年4胜的战绩，上上下下都觉得很不错。 第三年
， 搞来了超级RB Robert Turbin， 开始出成绩了（7胜）。 Robert Turbin这个赛季
在Seattle Seahawks有时候一场能跑100多yard。 Utah State能招来这么牛的人， 多
少是有点运气的。 从总体来看， Anderson是个很不错的教练，但这次能不能成功，
还是要看点运气。 |
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a**********e
发帖数: 147 | 3 1 piston engine plane 入门价格的，飞行速度最快也就200多公里/hour，而价格都可
以买2量porsche了。porsche开起来，自然很拉风。所以个人不是很看到慢速的piston
engine plane。如果仅仅是看看天上风景，一个hang glider 便宜也方便
2 速度比普通piston engine plane更快的，只有turbofan jet and turboprop plane,
前者就是所谓的涡轮喷气飞机，速度虽然快，但是跑道很长，而且废油。turboprop
plane也称为涡浆飞机，turbine推动前部螺旋桨，飞机在高速时，螺旋桨起到
compressor，来有效压缩turbine的进气，优点就是巡航速度，最高速度都比普通
piston engine plane更快。而油耗却和普通piston engine plane差不多，而且维护简
单，因为没有往复运动的piston，跑道长度也几乎一样，缺点就是飞行噪音大些，因为
螺旋桨转速较快，而且早期动力学设计不佳，容易产生激波，目前新的design下，噪音
问题已经比较小了
不知道，私人飞 |
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t******n
发帖数: 2939 | 4 ☆─────────────────────────────────────☆
mybasic (for life) 于 h 提到:
不知道还需要查啥？根源在哪里，怎么帮助宝宝变得健康点。
-----------
现在T4开始降低，开始用thyroid
--------
update
目前诊断是先天性垂体功能降低，虽然MRI 显示垂体正常，但是不协调分泌激素。
想不通为什么脑垂体有问题，影响了整个生长。
目前正在用hydrocortisone
生长素目前很低，但是不到能用药的程度，以后看是否会用生长素激素。
-------------------------------
求助，宝宝刚出生就进了NICU，麻烦有经验的父母或者医生，给点意见。
1.宝宝刚出生呼吸突然停止，脸发青，上了氧气抢救。呼吸一直急促，血糖低<20，心跳慢.
2.SpO2 每隔一两个小时左右就会降到60以下，大部分时间两分钟之内可自行恢复到90.偶尔给氧气.
2.刚出生在医院里连续输了三天葡萄糖和抗生素 （妈妈GBS positive，生产过快疫苗来不急）。刚出生葡萄糖浓度12.5％才能维持正常血糖。
3.第... 阅读全帖 |
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y*********u
发帖数: 14561 | 6 ☆─────────────────────────────────────☆
icyhui (Coco) 于 (Thu Jan 6 12:47:59 2011, 美东) 提到:
在此首先注明：小豆儿是一只4个月大的小女猫，不是小孩儿。sorry for the
misunderstanding
不知道该从哪里说起该怎么说该说什么，昨天从vet那里回来一边开车一路哭，小豆儿特别懂事，没
用carrier，只用leash套上放我怀里，小家伙儿静静地坐着睁大眼睛看着我哭，不叫也不闹让我安
心开车。她好像知道麻麻伤心了，自打她来我家从来没见我哭过，抱着她从来都是笑开怀。
小豆儿前些天精神不振，不爱玩，嗜睡，先前看了vet说没有大碍，开了点antibiotics，然后vet
提到小豆儿肚子有点大，让去化验下有没有寄生虫。我一开始以为是小豆儿吃太多所以肚子胀鼓鼓
的，没有太在意，但是还是把stool sma... 阅读全帖 |
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d*********e
发帖数: 3835 | 7 Currently we are searching for Avionics Senior Systems Project Engineers for
our client in Northern Connecticut. These opportunities are Longterm
consulting opportunities.
The responsibilities of the Avionics Sr. Systems Project Engineers include:
• Key focus on project execution of technical requirements to budget
and schedule through implementation of the Program Management System
Standard (PMSS) and the (IPD) Integrated Product Development Team process.
• Working knowledge of proc... 阅读全帖 |
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h****e
发帖数: 299 | 8 请教几个问题，我对发电机不懂，就是读wiki，大致原理可能是这样的：
发电厂一般有generator， 通过engine shaft 连接turbine，蒸汽发电。generator里
有excitor，excitor要有绝缘材料，例如plastic （我忘了suoliao怎么些了）。
turbine那会有overspeed trip。为什么发电机会overspeed，这个经常见吗？
如果哪个地方错了，请指正。谢谢热心人士。 |
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m********e
发帖数: 5088 | 9 I agree FEA is more important in gas turbine or aircraft engine. I also
agree FEA person should know design very well.
I am surprised you will say the design and FEA are the same person in GE.
From my experience, only a limited portion of people in GE "understand" FEA
even in gas turbine. (of coz, everyone can throw several terms). The main
stream of GE elites in design/engineering are edison engineers (I know you
will disagree, but they get promotions faster, right?). Most of them are
only unde... 阅读全帖 |
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m********e
发帖数: 5088 | 10 I agree FEA is more important in gas turbine or aircraft engine. I also
agree FEA person should know design very well.
I am surprised you will say the design and FEA are the same person in GE.
From my experience, only a limited portion of people in GE "understand" FEA
even in gas turbine. (of coz, everyone can throw several terms). The main
stream of GE elites in design/engineering are edison engineers (I know you
will disagree, but they get promotions faster, right?). Most of them are
only unde... 阅读全帖 |
|
m******8
发帖数: 160 | 11 One small family company is hiring a CNC manufacturing Engineer. The company
is in the field of after-market GAS Turbine engine parts design (Reverse-
Engineering) and manufacturing.
A successful candidate is going to be responsible for geometric measurement,
3D modeling (Solidworks), CNC machining process planning, CMM inspection.
CNC machining process planning for Gas Turbine vanes and blades is the major
responsibility. The company has a 5-axis superabrasive CNC grinding machine.
The candidat... 阅读全帖 |
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y*l
发帖数: 10 | 12 gas turbine, steam turbine, heat exchanger, heat recovery, combustor, oil&
gas, generator, motor, fired/unfired heater |
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a***n
发帖数: 1993 | 13 ASME-96-GT-259
Presented At The Interenational Gas Turbine And Aeroengine Congress &
Exhibition
Birmingham, U.K. June 10-12, 1996
Title: the effect of blade angle design selection on wave turbine engine
performance
Author: Lear, W.E.,Jr. |
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Y***o
发帖数: 4135 | 14 A gas turbine company (~200 employees) in LA.
Required MS/PhD in combustion (gas turbine preferred) with industrial
experience. Please PM if interested. |
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发帖数: 1 | 15 大家好，小弟是去年十二月从Texas A&M毕业的ME小硕一名，主要是design方向。找了
两个多月工作，一直在linkedin/careerbuilder/indeed/monster上面海投，也快三四
百份了，有过几个面试，然后也还是没找到工作。。。希望求助大家看有没有什么机会。
小弟主要做的是机械设计，原来本科的时候设计过三指机械手，2012年的时候在国内一
家火车线槽厂里实习两个月，主要也是画画AutoCAD图装配装配线槽什么的。来美国以
后做过car door protector/multi-stage gas turbine和irrigation runoff
mitigation system的设计，SolidWorks/AutoCAD/ProE都比较熟，UG也用过。有一些
hands-on experience，会用普通车床和laser cutter一类的工具。
也做过一些simulation的项目，比如模拟汽车engine performance和brake force，还
有gas turbine的压力和温度分布。Matlab经常会用，ANSYS(Fluent）和... 阅读全帖 |
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发帖数: 1 | 16 大家好，小弟是去年十二月从Texas A&M毕业的ME小硕一名，主要是design方向。找了
两个多月工作，一直在linkedin/careerbuilder/indeed/monster上面海投，也快三四
百份了，有过几个面试，然后也还是没找到工作。。。希望求助大家看有没有什么机会。
小弟主要做的是机械设计，原来本科的时候设计过三指机械手，2012年的时候在国内一
家火车线槽厂里实习两个月，主要也是画画AutoCAD图装配装配线槽什么的。来美国以
后做过car door protector/multi-stage gas turbine和irrigation runoff
mitigation system的设计，SolidWorks/AutoCAD/ProE都比较熟，UG也用过。有一些
hands-on experience，会用普通车床和laser cutter一类的工具。
也做过一些simulation的项目，比如模拟汽车engine performance和brake force，还
有gas turbine的压力和温度分布。Matlab经常会用，ANSYS(Fluent）和... 阅读全帖 |
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y*******n
发帖数: 10103 | 17 我查了一下书，
你说的这种是老式turbo，工作在“pressure mode”， 但现在新式的blowndown turbo
的back
pressure灰常小。
以下是引用书：
In the early days of turbo-charging, people thought they were doing well
having the compressor output pressure be as high as the exhaust back
pressure created by the presence of the turbine. This way partly because
they were operation the turbine in ”pressure mode“. meaning that they
treated the exhaust from the engine as if it were compressed air. High
velocity exhaust gas was decelerated in the manifold |
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V***b
发帖数: 3419 | 18 fresh air那一侧的压力是高于大气压的，如果lift throttle的时候不打开fresh air
inlet和outlet，在fresh air 的压力下turbine很快就减速了。
两个阀门一打开，让有压力高速运动的fresh air形成自循环维持turbine转速，等待排
气压力的升高。
BMW也提到了这个trick不能"work for extended time"，但没细说，我判断没有电机
"In "Sport" and "Sport Plus" settings, the turbochargers are "pre-tensioned,
" which means that they keep spinning at a high rate of speed even after you
have taken your foot off the throttle. This trick ensures ultra-quick
response times fully comparable to those of a naturally aspirated engi... 阅读全帖 |
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d******g
发帖数: 6966 | 19 不知道能不能在turbo机器上做一个引擎和turbine的机械连接，然后当中有个离合器，
普通模式下离合器是松开的保持turbo的高效率,在sport模式或者"快响应“模式下引擎
机械连接turbine牺牲效率换油门响应. |
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V***b
发帖数: 3419 | 20 看了这贴
http://www.mitbbs.com/clubarticle_t1/Auto_Fans/31540625_0_1.htm
我认为一些对turbo的描述不一定对，说一下我的理解
1. turbo介入的问题：比如2.0T的引擎并不是把2.0NA的潜力用尽之后turbo才介入的，
在低负载turbo就有介入。
2. turbo surge的问题：surge并不是延迟turbo介入 (帖子里所说的turbo lag) 的原
因。2.0NA进气压强低于一个大气压，排气压强，即便是低负载，无论如何也比这个高
，哪来的surge呢。通常说的surge是turbo高强度工作，比如大油门冲直线，入弯道前
收油猛刹车，这一瞬间进气侧压强大，排气侧压强突然减小，会出现surge。
3. turbo lag的问题：这个并不是surge造成的。原因之一是turbo机torque曲线很陡，
在低负载的时候排气压力小进气效率比NA机高不了多少（但仍然是高），rpm上去了之
后，torque很快攀升，给人感觉是很peaky，很多人把这个叫lag。所以lag更多的是描
述一个主观感受。另一个原因是空气动... 阅读全帖 |
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e**n
发帖数: 1326 | 21 碳大，我有一点不明白：
"因为差那么一点flow就不够了，turbo就会surge，根本没法推出700rpm就能介入……"
我对surge的理解是排气端流量够推动turbine，但是发动机不需要那么多进气，如果不
用wastegate放气的话，最后会导致compressor那端压缩了很多空气但是走不掉，于是
compressor叶片stall，turbo转速飙升？类似喷气机的暴冲？
如果是这样的话，那700rpm flow不够的应该是turbine那端而不是compressor那端？假
设如果是compressor 那端flow不够的话可以通过wastegate泻掉一点，但是还是能保持
一部分boost的？ |
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p*********e
发帖数: 32207 | 22 我刚开始也觉得不太好理解，但转念想，
高转速虽然排气量大，但转速高了意味着单位时间需要的进气量也大，
同时转速高意味着进气时间窗口更小，你可能需要进气增压更高才能让缸内进气冲程结
束后压强足够高
那么两者结合，意味着compressor需要做的功（对进气压缩）更多，
进而意味着turbine需要更大的排气量来吹动
看图里，高转下1bar左右工况下wastegate是基本全开的，但负载进一步增高后反而要
关wastegate
我觉得就是因为上面的原因产生这个区别
这个图是从一个加起来两百页左右的n54技术文档里摘出来的，算是比较specific了，
按说不至于只是一个sketchy的概念演示图。
或许这个差别是因为wrx和n54 335i所用turbine和compressor的profile不同导致的？
你那个图比较conceptual 所以比较好理解。但实践上，如果最高boost 5000rpm |
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p*********e
发帖数: 32207 | 23 要想没lag，平时就在s挡开
转速在2k左右巡航的话，
意味着随时深踩油都可以近实时提供的让turbine转速足够的排气量
那么lag就非常小
如果是D挡，常常是在1000-1500，这时候你深踩油门到turbine全速，就会明显延迟
35i
anti- |
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f**********g
发帖数: 2252 | 24 UP.
The Long Case for Avalon Rare Metals
2 comments | by: Michael Filloon February 08, 2011 |
about: ARAFF.PK / AVL / MCP / QSURD.PK / REE
Rare Earth Elements or REEs seem to be the newest big mover on Wall Street.
Although most have heard of them, they do not know what their use is. The
best way to identify them is by going back to chemistry class and looking at
a periodic table. Here is an easier introduction.
Avalon Rare Metals Inc. (AVL) has seen a large appreciation of market cap
ove... 阅读全帖 |
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f**********g
发帖数: 2252 | 25 UP.
The Long Case for Avalon Rare Metals
2 comments | by: Michael Filloon February 08, 2011 |
about: ARAFF.PK / AVL / MCP / QSURD.PK / REE
Rare Earth Elements or REEs seem to be the newest big mover on Wall Street.
Although most have heard of them, they do not know what their use is. The
best way to identify them is by going back to chemistry class and looking at
a periodic table. Here is an easier introduction.
Avalon Rare Metals Inc. (AVL) has seen a large appreciation of market cap
ove... 阅读全帖 |
|
f**********g
发帖数: 2252 | 26 UP in pre-market.
The Long Case for Avalon Rare Metals
2 comments | by: Michael Filloon February 08, 2011 |
about: ARAFF.PK / AVL / MCP / QSURD.PK / REE
Rare Earth Elements or REEs seem to be the newest big mover on Wall Street.
Although most have heard of them, they do not know what their use is. The
best way to identify them is by going back to chemistry class and looking at
a periodic table. Here is an easier introduction.
Avalon Rare Metals Inc. (AVL) has seen a large appreciation of ... 阅读全帖 |
|
f**********g
发帖数: 2252 | 27 UP in pre-market.
The Long Case for Avalon Rare Metals
2 comments | by: Michael Filloon February 08, 2011 |
about: ARAFF.PK / AVL / MCP / QSURD.PK / REE
Rare Earth Elements or REEs seem to be the newest big mover on Wall Street.
Although most have heard of them, they do not know what their use is. The
best way to identify them is by going back to chemistry class and looking at
a periodic table. Here is an easier introduction.
Avalon Rare Metals Inc. (AVL) has seen a large appreciation of ... 阅读全帖 |
|
y*****l
发帖数: 5997 | 28 GE start Solar now.
UPDATE: GE Unveils Plans For US Thin-Film Solar Panel Factory
Thursday 04/07/2011 03:45 PM ET - Dow Jones News
(Updates with executive interview, additional details and background
throughout.)
By Bob Sechler
Of DOW JONES NEWSWIRES
General Electric Co. (GE) is aiming to build up its nascent solar energy
business on a scale of its $6 billion wind-turbine unit, announcing plans
Thursday for what it said will be the biggest photovoltaic panel factory in
the U.S.
"We're looking to... 阅读全帖 |
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f**********g
发帖数: 2252 | 29 Ener1 and Federal Grid Company to Demonstrate Lithium-Ion Distributed Energy
Storage System at St. Petersburg International Economic Forum
49 minutes ago - PR Newswire via Comtex
PR NewswireEner1, Inc. (NASDAQ: HEV) and the Russian Federal Grid Company (
FGC) (MICEX: FEES) today announced they will display a fully operational,
lithium-ion, distributed energy storage system as part of the 15th annual St
. Petersburg International Economic Forum which will be held June 16-18 in
Russia. The Forum w... 阅读全帖 |
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y***q
发帖数: 4147 | 30 Do you think these stocks should be trading higher? Use this list as a
starting point for your own analysis.
List sorted by potential upside implied by target price.
1. Warren Resources Inc. (WRES): Engages in the exploration, development,
and production of onshore crude oil and gas reserves in the United States.
Market cap of $213.84M. Price (as of market close on 12/19) at $2.99. Of the
5 analysts that have set a target price on the stock, the lowest price
target stands at $4.00. This implies ... 阅读全帖 |
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m*********k
发帖数: 10521 | 31 成功奖励 20 伪币的用户:
ludiman, kaleege, tengzi, galoisxu, LEAUPARKENZO, hwholiday, StephenKing,
snoopyB, qingshuiyi, duckling1316, yikedami, jcpennyny, syyssy, youfenglei,
qiaka, cynic, MAKEWISH, windloren, nellie, zhaoju2000, turbine, stevenxu,
Sleepingbag, wh, faintcat, avalanche7
奖励版面:(ChinaNews)20伪币成功
奖励版面:(Family)20伪币成功
奖励版面:(Fitness)20伪币成功
奖励版面:(Immigration)20伪币失败 原因:版面现金超过正极限值
奖励版面:(LoveNLust)20伪币成功
奖励版面:(MedicalCareer)20伪币成功
奖励版面:(Military)20伪币失败 原因:版面现金超过正极限值
奖励版面:(NextGeneration)20伪币成功
奖励版面:(... 阅读全帖 |
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a**********e
发帖数: 147 | 32 1 piston engine plane 入门价格的，飞行速度最快也就200多公里/hour，而价格都可
以买2量porsche了。porsche开起来，自然很拉风。所以个人不是很看到慢速的piston
engine plane。如果仅仅是看看天上风景，一个hang glider 便宜也方便
2 速度比普通piston engine plane更快的，只有turbofan jet and turboprop plane,
前者就是所谓的涡轮喷气飞机，速度虽然快，但是跑道很长，而且废油。turboprop
plane也称为涡浆飞机，turbine推动前部螺旋桨，飞机在高速时，螺旋桨起到
compressor，来有效压缩turbine的进气，优点就是巡航速度，最高速度都比普通
piston engine plane更快。而油耗却和普通piston engine plane差不多，而且维护简
单，因为没有往复运动的piston，跑道长度也几乎一样，缺点就是飞行噪音大些，因为
螺旋桨转速较快，而且早期动力学设计不佳，容易产生激波，目前新的design下，噪音
问题已经比较小了
不知道，私人飞 |
|
l*******n
发帖数: 102 | 33 TIANJIN, China — China vaulted past competitors in Denmark, Germany, Spain
and the United States last year to become the world’s largest maker of wind
turbines, and is poised to expand even further this year.
China has also leapfrogged the West in the last two years to emerge as the
world’s largest manufacturer of solar panels. And the country is pushing
equally hard to build nuclear reactors and the most efficient types of coal
power plants.
These efforts to dominate renewable energy technologi |
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n*******e
发帖数: 1141 | 36 NHK TEPCO forced to change strategy at plant
http://www3.nhk.or.jp/daily/english/26_08.html
Tokyo Electric Power Company has been forced to change its strategy at the
quake-hit Fukushima Daiichi nuclear power plant due to high radiation levels
at the site.
The plant's nuclear reactors 1 through 4 have all lost their cooling
capabilities as both external and backup power supplies failed after the
quake and tsunami.
TEPCO has been working to restore the external power supply while trying to
cool t... 阅读全帖 |
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c**i
发帖数: 6973 | 37 (1) Editorial: The Coming Renaissance in U.S. Manufacturing. Washington Post
, May 10, 2011.
http://www.washingtonpost.com/opinions/the-coming-
renaissance-in-us-manufacturing/2011/05/10/AFRI53jG_story.html
Quote:
China is "surging from 3 percent of global factory output in 1990 to 19.8
percent in 2010, just ahead of the U.S. share, 19.4 percent.
"Manufacturers have hired just 250,000 workers [in US] since December 2009,
when manufacturing employment hit a postwar low of 11.5 million.
"A key imp... 阅读全帖 |
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p*********w
发帖数: 23432 | 38 死胖子艾未未获颁英国荣誉院士zz
艾未未获颁英国荣誉院士 (08:30)
英国皇家艺术学院颁授荣誉院士，予被中国当局拘捕的艺术家艾未未。
英国皇家艺术学院表示，艾未未是中国甚至全球同代人中，其中一个最重要的文化人物
。学院在声明中，没有提及艾未未被拘捕的事。
英国皇家艺术学院每年都会选出两名不在英国居住的艺术家，作为荣誉院士，今年另一
位获得这个头衔的是荷兰画家柯克比。
（路透社）
路透社原文：
UK's Royal Academy gives Ai Weiwei honorary title
Wed Jun 1, 2011 4:47pm EDT
LONDON (Reuters) - Britain's Royal Academy has made detained Chinese artist
Ai Weiwei an honorary member alongside Danish painter Per Kirkeby, the
prestigious London art institution said on Wednesday.
The title of Honorary ... 阅读全帖 |
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D*V
发帖数: 3096 | 39 WASHINGTON (MarketWatch) - President Barack Obama has prohibited a Chinese-
owned company from building wind farms near a U.S. Navy installation in
Oregon, the White House announced Friday. Obama rejected a bid by Ralls Corp
, a firm owned by Chinese nationals and affiliated with a Chinese
construction equipment company that manufactures wind turbines. The
Committee on Foreign Investment in the U.S., or CFIUS, has already rejected
the wind farm project. Under the order, Ralls must divest its int... 阅读全帖 |
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E*V
发帖数: 17544 | 40 F-35 又出问题了？
来源: IQ88 于 2013-02-22 13:57:12[档案] [博客] [旧帖] [转至博客] [给我悄悄
话] 本文已被阅读：452次
字体：调大/调小/重置 | 加入书签| 打印| 所有跟帖 | 加跟贴| 查看当前最热讨论主题
http://news.yahoo.com/pentagon-suspends-f-35-flights-due-crack-
WASHINGTON (Reuters) - The Pentagon on Friday suspended the flights of all
51 F-35 fighter planes after a routine inspection revealed a crack on a
turbine blade in the jet engine of an F-35 test aircraft in California.
It was the second grounding of the warplane in two months and marked another
setback ... 阅读全帖 |
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h**e
发帖数: 9290 | 41 http://www.ocef.org/publication/donor-newsflash/715--20158-dono
2015暑期专辑/2015 Summer Special
每年暑假，OCEF的义工和捐款人从全国各地甚至是全球各个角落而来，利用休假或回国
探亲的机会进行支教或走访学校，亲身体验助学活动。在本期的捐款人快讯，我们特地
选取了两篇义工见闻，与大家一起分享他们的心得和快乐。
Every summer, OCEF volunteers and donors from all over the world spend their
vacation time to visit OCEF-sponsored schools or to help in teaching, in
the process gaining first-hand experiences in the mission and functions of
OCEF. In this issue of the newsflash, we would like to share the stories an... 阅读全帖 |
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h**e
发帖数: 9290 | 42 http://www.ocef.org/publication/donor-newsflash/715--20158-dono
2015暑期专辑/2015 Summer Special
每年暑假，OCEF的义工和捐款人从全国各地甚至是全球各个角落而来，利用休假或回国
探亲的机会进行支教或走访学校，亲身体验助学活动。在本期的捐款人快讯，我们特地
选取了两篇义工见闻，与大家一起分享他们的心得和快乐。
Every summer, OCEF volunteers and donors from all over the world spend their
vacation time to visit OCEF-sponsored schools or to help in teaching, in
the process gaining first-hand experiences in the mission and functions of
OCEF. In this issue of the newsflash, we would like to share the stories an... 阅读全帖 |
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V****n
发帖数: 651 | 43 外行人真是不知道研制发动机要多少人力物力
单就人力来说罢，不要说GE, PW，就算是RR或小点的HW也是成批的PHD(turbine,
compressor, combustor等分部门都如此)。绝不是一两百个本科生去学学怎么使用几个
流体力学的软件就可以做出来的。比如燃烧领域，最好的PHD program中的Princeton,
Yale, Michigan都有很多PHD在 GE aircraft engine (辛辛那提)或NY州的research
center。
国内搞设计的本科出来到美国的基本上都改行了。少数有能力的(大多是北航，也有清
华，科大的)在美国机械或航空系(很多学校将这两个系合并)拿了PHD后一般也不会入此
行。简单一个原因就是起码要有绿卡。军用项目不但要公民，还要security clearance
。另外，本科阶段没有学好流体力学，空气动力学，热传递，燃烧学，计算流体力学等
科目根本就不可能学好设计。真正设计中遇到的很多问题都是学术界没有解决的问题，
比如multiphase flow, turbulence-chemistry interaction, det |
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k***i
发帖数: 462 | 44 风力发电成本一点不高。美国的风力发电厂平均7到10年就能收回成本。上次和一个
Iowa的老美谈，据她说Iowa有些风力发电厂仅用两年就收回了成本，capacity factor
比预想的高许多。Midwest的农民现在特喜欢风力发电厂，一个turbine占半英亩地，每
年租金5000刀左右，而且若干年后就归农民所有，比种地挣钱多了。主要问题是对电网
的冲击比较大，需要很大的火力或者核电站匹配。甘肃的风电建了好多都没实际运行，
跟当地缺水缺大型电站也有关系。 |
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d*b
发帖数: 21830 | 45 主要供应杭州湾一带的国华燃气电厂发电之用。国华电厂有无数分厂，是引进GE gas
turbine干的。N年前的老闻了。 |
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m**w
发帖数: 39 | 46 http://www.nytimes.com/2010/09/23/business/global/23rare.html?src=busln
In Dispute, China Blocks Rare Earth Exports to Japan
HONG KONG — Sharply raising the stakes in a dispute over Japan’s
detention of a Chinese fishing trawler captain, the Chinese government
has placed a trade embargo on all exports to Japan of a crucial category
of minerals used in products like hybrid cars, wind turbines and guided
missiles.
China Takes a Sharper Tone in Dispute With Japan (September 23, 2010)
Chinese custom |
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g********s
发帖数: 590 | 47 China Blocks Export of Crucial Minerals to Japan as Dispute Escalates
Sharply raising the stakes in a dispute over Japan's
detention of a Chinese fishing trawler captain, the Chinese
government has placed a trade embargo on all exports to Japan
of a crucial category of minerals used in products like
hybrid cars, wind turbines and guided missiles.
Chinese customs officials are halting all shipments to Japan
of so-called rare earth elements, industry experts said on
Thursday morning.
Read More:
ht |
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n******e
发帖数: 281 | 48 "The NY Times reports that the Chinese government has placed a trade embargo
on all exports to Japan of a crucial category of minerals used in products
like hybrid cars, wind turbines and guided missiles. China mines 93 percent
of the world's rare earth minerals, and more than 99 percent of the world's
supply of some of the most prized rare earths, which sell for several
hundred dollars a pound. The embargo comes after a dispute over Japan's
detention of a Chinese fishing trawler captain whose s |
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T**********r
发帖数: 1223 | 49 http://web.stratfor.com/images/writers/CHINA_RARE_EARTH_ELEMENTS.pdf?fn=9617327557
China and the Future of Rare Earth Elements
October 14, 2010
clip_image002
STRATFOR
PDF Version
* Click here to download a PDF of this report
A recent diplomatic spat between China and Japan has heightened territorial
tensions and called attention to China’s growing forcefulness with foreign
powers. One of the more intriguing aspects of this development was China’s
suspension of the export of “rare ea... 阅读全帖 |
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o********r
发帖数: 775 | 50 http://www.chinadaily.com.cn/china/2010-10/19/content_11426106.htm
China to reduce rare earth export quotas
(China Daily)
Updated: 2010-10-19 07:05 Comments(1) PrintMail Large Medium Small
Technicians work at the production facility of Inner Mongolia Baotou Steel
Rare-Earth Hi-Tech Co in Baotou, Inner Mongolia autonomous region. Chinese
officials said the country's rare earth reserves will last for 15 to 20
years. [Photo/Agencies]
Beijing - China will further reduce quotas for rare earth expo... 阅读全帖 |
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