Unitarity Bounds and the Cuspy Halo Problem
a r X i v :a s t r o -p h /0102349v 3 30 M a y 2002
Unitarity Bounds and the Cuspy Halo Problem
Lam Hui
Department of Physics,Columbia University,538West 120th Street,New York,NY 10027
Institute for Advanced Study,School of Natural Sciences,Princeton,NJ 08540
lhui@https://www.wendangku.net/doc/e98500594.html, Conventional Cold Dark Matter cosmological models predict small scale structures,such as cuspy halos,which are in apparent con?ict with observations.Several alternative scenarios based on modifying fundamental properties of the dark matter have been proposed.We show that general principles of quantum mechanics,in particular unitarity,imply interesting constraints on two pro-posals:collisional dark matter proposed by Spergel &Steinhardt,and strongly annihilating dark matter proposed by Kaplinghat,Knox &Turner.E?cient scattering required in both implies m ～<12GeV and m ～<25GeV respectively.The same arguments show that the strong annihilation in the second scenario implies the presence of signi?cant elastic scattering,particularly for large enough masses.Recently,a variant of the collisional scenario has been advocated to satisfy simultaneously constraints from dwarf galaxies to clusters,with a cross section that scales inversely with velocity.We show that this scenario likely involves super-elastic processes,and the associated kinetic en-ergy change must be taken into account when making predictions.Exceptions and implications for experimental searches are discussed.
98.89.Cq;98.80.Es;98.62.Gq;11.80.Et;11.55Bq
I.INTRODUCTION
There is a long history of e?orts to constrain dark mat-ter properties from galactic structure (e.g.[1]).Recent numerical simulations [2]sharpen the predictions of Cold Dark Matter (CDM)structure formation models,and apparent discrepancies with the observed properties of structures from galactic to cluster scales are uncovered.The main one that has attracted a lot of attention is the cuspy halo problem ,namely that CDM models predict halos that have a high density core or have an inner pro-?le that is too steep compared to observations ([3],but see also [4]).This has encouraged several proposals that dark matter might have properties di?erent from those of conventional CDM (see [5]and summary therein).On the other hand,general principles of quantum me-chanics impose non-trivial constraints on some of these models.We focus here on the proposals of collisional or strongly self-interacting dark matter (SIDM)by [6]and of strongly annihilating dark matter (SADM)by [7].Both require high level of interaction by particle physics standard:an elastic scattering cross-section of σel .～10?24(m X /GeV)cm 2for the former and an annihilation cross-section of σann .v rel ～10?28(m X /GeV)cm 2for the latter,where m X is the particle mass,and v rel is the rel-ative velocity of approach.The proposed dark matter is therefore quite di?erent from usual candidates such as the axion or neutralino.We show that the unitarity of the scattering matrix,together with a few reasonable as-sumptions,imposes interesting particle mass bounds as well as other physical constraints.This is done while making minimal assumptions about the nature of the interactions.Our results complement constraints from experiments or astrophysical considerations e.g.[8].
Griest and Kamionkowski [9]previously derived similar mass bounds related to the freeze-out density of thermal relics,assuming 2-body ?nal states.In §II,we provide a general derivation for arbitrary ?nal states using the classic optical theorem [10].We summarize our ?ndings in §III,discuss exceptions to our bounds,and other so-lutions to the cuspy halo problem.
II.DERIVING THE UNITARITY BOUNDS
Di?erent versions of the unitarity bounds can be found in many textbooks,and can be most easily un-derstood using non-relativistic quantum mechanics (e.g.[11]),which is probably adequate for our purpose.How-ever,the results and derivation given here might be of wider interest e.g.for estimating thermal relic density.Here we follow closely the ?eld theory treatment of [12].The optical theorem [10]is a powerful consequence of the unitarity of the scattering matrix S ,i.e.S ?S =1,which implies (1?S )?(1?S )=(1?S ?)+(1?S ),or
dγ β|1?S |γ γ|1?S ?|α =2Re β|1?S |α (1)where αand βrepresent two speci?ed states and γrep-resents a complete set of states with measure dγ.Using the de?nition of the scattering amplitude A βα
β|1?S |α ≡?i (2π)4δ4(p β?p α)A βα
(2)
where p βand p αare the total four-momenta,one obtains
dγ(2π)4δ4(p α?p γ)|A γα|2=2Im A αα(3)
if β=αin eq.(1).We
are
interested in the case where α
represents a 2-body state of X +X or X +ˉX
approach-ing each other.The ?nal state γ,on the other hand,is completely general,and the integration over γcovers the entire spectrum of possible ?nal states.To be more
precise,suppose |α =|k 1,s z 1;k 2,s z 2;n where s z 1and s z
2represent the spin-states of the two incoming particles with spins s 1and s 2(in our particular case,s 1=s 2)while k 1and k 2are their respective 4-momenta,and n labels the particle types (e.g.mass,etc.).Recalling that dσ/dγ∝|A γα|2,eq.(3)gives in the center of mass frame (adopted hereafter i.e.k 1+k 2=0):
dγ
dσ
2(E 1+E 2)|k 1|(4)where the left hand side is exactly the total cross-section.This is the optical theorem.It states that the total cross-section for scattering from a two-body initial state to all possible ?nal states equals the imaginary part of the two-body to two-body forward scattering amplitude.
To use this theorem,we expand the scattering am-plitude in terms of partial waves i.e.states labeled as |k tot .,E tot .,j,j z ,?,s,n where k tot .is the total linear mo-mentum (=0in the center of mass frame),E tot .is the total energy ,j is the total angular momentum,j z is its z-component,?is the orbital momentum and s is the to-tal spin.Inserting appropriate complete sets of partial wave outer products into eq.(2),we obtain
A βα=4i (2π)2[E ′1+E ′
2/|k ′1|]
1
2
(5)
j,j z
?′,s ′,?,s
?′s ′n ′|1?S |?sn j,E tot .
?z ′,s z ′
s ′s z ′|s z 1′s z 2′ s ′1,s ′2
jj z |?z ′s z ′ ?′,s ′ ?k ′1|?′?z ′
?z ,s z
ss
z
|s z 1s z 2 ?
s 1,s 2 jj z |?z s z ??,s ?k 1|??z
?where the crucial assumption is that S is rotationally
invariant and so j and j z are conserved,in addition to energy conserving.The notation ?′s ′n ′|1?S |?sn j,E tot .emphasizes that S is diagonal in j ,j z and E tot but the j z dependence drops out because S commutes with J x ±iJ y .
The inner products ss z |s z 1s z
2 s 1,s 2and jj z |?z s z ?,s give
the Clebsch-Gordon coe?cients,and ?k
1|??z =Y ??z (?k 1)is the spherical harmonic function.We assume ?k 1=?z in which case Y ??z (?k 1)=δ?z ,0
|k 1|2(2s 1+1)(2s 2+1)
j (2j +1)(6)
?,s
Re ?sn |1?S |?sn j,E tot .
This gives the total spin-averaged cross-section for scat-tering from X +X or X +ˉX
to all possible ?nal states.For X +ˉX
annihilation,we exclude from the above the contribution due to elastic scattering (where type and
mass of particles do not change i.e.X +ˉX
→X +ˉX ,implying |k ′1|=|k 1|)[9].To do so,we need the following expression for 2-body to 2-body scattering cross-section:
dσ
4(E 1+E 2)|k 1|
(2π)4δ4(p β?p α)dβ,
(7)
We average over initial spin states and integrate over out-going momenta,but focus on the elastic contribution (n ′
in |β =|k ′1,s ′1;k ′2,s ′2;n ′
is set to n in |α )[12]:
σel .=
π
k 21(2s 1+1)(2s 2+1)
j (2j +1)(9) ?,s
[1?| ?sn |S |?sn |2? ?′=?,s ′=s
| ?′s ′n |1?S |?sn |2]
From eq.(6)&(9),we can derive two bounds:
σtot .≤4π[|k 1|2(2s 1+1)(2s 2+1)]?1
j
?,s
2j +1(10)σinel .≤π[|k 1|2(2s 1+1)(2s 2+1)]?1
j
?,s 2j +1(11)
The ?rst inequality uses | ?sn |S |?sn |2≤1,ob-tained from
dγ ?sn |S ?|γ γ|S |?sn ≥| ?sn |S |?sn |2and S ?S =1.A similar bound can be derived for σel .as well,which coincides exactly with that for σtot ..
We pause to note that the above bounds assume only unitarity and the conservation of total energy and lin-ear and angular momentum.No assumptions are made about the nature of the particles,whether they are com-posite or point-like.Nor do we assume the number of particles in the ?nal states.To obtain useful limits from the bounds,we take the low velocity limit.Assuming the scattering amplitude A βαis an analytic function of k 1as k 1→0(exceptions will be discussed in §III),and noting
that k ? ?k
|??z is a polynomial function of k ,we expect the ?partial wave contribution to A βα(eq.5)to scale as |k 1|?.This means in the low velocity limit,as is rele-vant for our purpose (typical velocity dispersion in halos range from 10to 1000km/s ?c ),the ?=0or s-wave contribution dominates.Setting ?=0in eq.(10),(11):
σtot.≤16π/(m X v rel)2,σinel.v rel≤4π/(m2X v rel)(12) where k21=m2X|v2?v1|2/4=m2X v2rel/4is used.The second inequality agrees with[9].Hence,
σtot.≤1.76×10?17cm2 GeV v rel. 2(13)σinel.v rel.≤1.5×10?22cm2 GeV v rel. (14)
Furthermore,ifσinel.is bounded from below,sayσinel.≥σann.,one can derive a lower bound onσhttps://www.wendangku.net/doc/e98500594.html,ing eq.
(8)&(9),and setting?=0.De?ning X J≡[(2s1+ 1)(2s2+1)]?1 j,?,s(2j+1)X,using S at the moment to denote ?sn|S|?sn ,and noting that 1 J=1for?=0,it can be shown(π/k21)(1? |S| 2J)≥(π/k21)(1? |S|2 J)≥σinel.≥σann.,which implies |S| J≤
1?k21σann./π]2(15)
This tells us that the elastic scattering cross-section can-not be arbitrarily small given a non-vanishing inelastic cross-section,e.g.via annihilation.
The above3bounds are the main results of this section. Two more results will be useful for our later discussions. For two-body to two-body processes,recall that the?,?′contribution to Aβαscales as|k1|?|k′1|?′.Using dσ/d?= |Aβα|2(|k′1|/|k1|)/[64π2(E1+E2)2](obtained from eq.7 by integrating overβexcept for solid angle?),it can be seen that for elastic scattering,where|k′1|=|k1|,
dσ/d?→const.[1+O(v rel.)](16) as|k1|→0.For inelastic scattering where the sys-tem gains kinetic energy by losing rest mass(e.g.de-excitation of a composite particle or annihilation),since |k′1|approaches a non-zero value as|k1|→0,we have dσ/d?→(const./v rel.)[1+O(v rel.)](17) instead in the low velocity limit.The opposite case where the particle gains mass is discussed in[12].
III.DISCUSSION
We can derive the following four constraints for strongly self-interacting dark matter(SIDM)[6]and strongly annihilating dark matter(SADM)[7].
1.The rangeσel.～10?24?10?23cm2(m X/GeV)is given by[5]for SIDM to yield the desired halo properties. Using the lowerσel.,and v rel.～1000km/s(appropriate for clusters),eq.(13)tells us m X～<12GeV for SIDM.
2.The annihilation cross-section from[7],σann.v rel.～10?28cm2(m X/GeV),together with eq.(14)and v rel.～1000km/s,gives us a bound of m X～<25GeV for strongly annihilating dark matter.
3.For SADM,e?cient annihilation(a form of inelastic scattering)inevitably implies some elastic scattering as well.From eq.(15),and using v vel～1000km/s as before,we have
σel.≥4×10?22cm2[GeV/m X]2(18)
[1?
cases,higher partial waves in addition to s-wave gener-ally contribute,andσtot.～<64πR2and our arguments turn into a limit on R[9].The condition|k1|R>1gives the most stringent constraint on R for v rel.=10km/s,as appropriate for dwarf galaxies:R～>10?9cm(GeV/m X). One can compare this with R for neutron-neutron scat-tering～10?13cm[17].
It is intriguing that halo structure might be telling us the elementary properties,in particular the mass,of dark matter.It is interesting that several proposals to ad-dress the cuspy halo problem,such as Warm Dark Matter [18]and Fuzzy Dark Matter[19]make explicit assump-tions about the mass of the particles–m X～1keV and m X～10?22eV respectively.For SIDM and SADM,as-trophysical considerations generally only put constraints on the cross-section per unit mass.We have shown here that unitarity arguments imply a rather modest mass for both scenarios as well.It is also worth pointing out that our arguments,with suitable modi?cation to take into account bose enhancement and multiple incoming parti-cles,can be extended to cover dark matter in the form of a bose condensate,as has been proposed as yet another solution to the cuspy halo problem[20].They generally require small masses as well～<10eV.
A few issues are worth further investigation.Wan-delt et al.[8]recently argued a version of SIDM,where the dark matter interacts strongly also with baryons,is experimentally viable,but requires m X～>105GeV,or m X～<0.5GeV.Our bound here is inconsistent with the large mass region(but see exceptions above);exper-imental constraints on the low mass region will be very interesting(σel.～<10?25cm2).It would be useful to?nd a micro-physics realization of the collisional scenario[21] or its variant whereσscales appropriately with velocity to match observations.The impact of inelastic collisions on halo structures is worth exploring in more detail.It is also timely to reconsider possible astrophysical solu-tions to the cuspy halo problem,such as the use of mass loss mechanisms[22].We hope to examine some of these issues in the future.
ACKNOWLEDGMENTS
The author thanks Manoj Kaplinghat,Avi Loeb,Dam Son,Paul Steinhardt and Igor Tkachev for useful discus-sions,and Jonathan Feng,Andrei Gruzinov and Yossi Nir for helpful comments.Thanks are due to David Spergel for pointing out the example of neutron scattering,and to Kim Griest and Marc Kamionkowski for educating the author on elastic scattering,which led to a tightening of a bound from an earlier version.Support by the Taplin Fellowship at the IAS,and by the Outstanding Junior Investigator Award from DOE,DE-FG02-92-ER40699, is gratefully acknowledged.
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光晕1中文版攻略
光晕1中文版攻略.txt我爸说过的最让我感动的一句话：“孩子，好好学习吧，爸以前玩麻将都玩儿10块的，现在为了供你念书，改玩儿1块的了。”Campaign 1: Pillar of Autumn 游戏开始，从一个培养舱中醒来，有一个导师就在你的身边，你现在要做的就是按照他的要求开始一些基本的训练，熟悉游戏的操作。这个过程比较简单，按E键走出培养舱，然后站到红格子里测试传感器，用鼠标划过前方五个闪光的目标即可，这时上下的控制会颠倒设置，如果不喜欢这种设定按ESC键就可以取消，也可以在设置界面里恢复。再按E键退出，跟着导师走到另一侧测试护甲，充上能量后导师与控制室里的长官Keyes对话，没想到怪物的军队出现，将Keyes击倒，OK，闲散时刻结束，进入战斗状态。 Mission：Find Captain Keyes 任务要求去找到Keyes，导师会和你一起前去寻找Keyes，让导师走在前面，你在后面跟着，保持一定的距离，走出不远，在一段长廊上，他会被敌人攻击而死。放下他的尸体继续前进，从一段管道过去来到一条走廊，在前方的转弯处向由，穿过一道门后（注意看灯的颜色，红灯无法通过，绿色灯的门才能打开），在拐角处左转，蹲下通过半掩的门。随后会在前方发现地面上有蓝色的箭头，顺着箭头前进，到尽头通过一道门后会出现一个绿色的大怪物，一个人作战会很吃力，不过幸好片刻之后就会有援军赶到，帮忙将这怪物击败。随后继续前进，遇到一队正在和敌人战斗的船员，不用管这里的战斗，跟着一个船员的引导，向舰桥方向过去，这个船员会消灭中途出现的敌人，所以你只管向舰桥方向跑就可以了。来到舰桥后，见到了Keyes，他说舰船上现在的情形非常地糟糕，估计飞船已经没办法再抵抗敌人的进攻了，现在唯一的选择就是弃船。在Keyes的命令下，你赶紧带着电子人Cortana逃吧。临行前，Keyes会将身上带的一把枪给你战斗之用。 Mission：Get off the Pillar of Autumn 有了枪就等于有了战斗能力。离开舰桥的道路上会有一些子弹作为补充，中途还可以获得MA5B型来复枪。前进到一间房间里会发现一帮船员在个怪物们战斗，帮助船员们消灭怪物后离开，来到一道走廊，从中间一道打开的门过去，小心前面红色的墙壁，不一会就会爆炸，大量的怪物就会从这里涌出来。将这些怪物们全部干掉后，从地面上有绿色箭头的位置前进，路上又回看到在和怪物们战斗的船员们。仍然协助船员将敌人全部消灭，然后从箭头所指的位置过去，在一个有烧着的铁桶的位置附近有一个不大的门缝，从这里钻过去就会看到楼梯。还没等走到楼梯，就会有大量的敌人涌出去。干掉他们后上楼，把上层的怪物们全部解决。接下来要对付的敌人麻烦一些，不要直接和他们冲突，一旦被他们近身的话，你的麻烦就大了。走廊上的桶是掩护自己作战的良好道具，远距离将它们全部杀死后从走廊过去，这时会看到，大量的船员已经开始乘坐逃生舱发射出了飞船。但是当自己到达走廊尽头的位置却发现所有的逃生舱都已经发射掉了。 现在唯一的办法就是去维修舱那里找逃生舱。转弯之后的路比较难走，从入口进去，向左沿着路一直前进，在有岔路的地方右转，然后再直走，走到尽头，发现门已经锁上了，讲文明有礼貌的那一套没用了，砸开门进去，所有的分岔路都向左转，中途的敌人难度不大，消灭即可。一直前进最后回到游戏开始时进行训练的房间，通过这里后转左，从一道铁门处进入通道内，通道有分岔路，在第一个岔口处转左，第二个岔路口转右，之后的分岔路任意选择一条均可以到达目的地。会合了这里的一些队员后继续前进，途中可以学得投掷技能，最后可以找到一道绿色的门，进入之后就可以乘上逃生舱离开飞船。
浅谈碧昂丝《halo》的演唱技巧及演唱风格
┊┊┊┊┊┊┊┊┊┊┊┊┊装┊┊┊┊┊订┊┊┊┊┊线┊┊┊┊┊┊┊┊┊┊┊┊┊序号（学号）：241140402 长春大学 毕业设计（论文） 浅谈碧昂丝《halo》的演唱技巧及演唱风格 姓名陈圆圆 学院音乐学院 专业音乐表演（歌舞） 班级2411404 指导教师王熠娜 2014 年12 月15 日
┊ ┊┊┊┊┊┊┊┊┊┊┊┊装┊┊┊┊┊订┊┊┊┊┊线┊┊┊┊┊┊┊┊┊┊┊┊┊ 浅谈碧昂丝《halo》的演唱技巧及演唱风格 摘要:每一个人对于歌曲的感觉或许已经不是那么陌生了，每一首歌曲会给大家带来怎么样的听觉感受都是我们对于评定一首歌曲好坏的重要标准，也是衡量一个歌手对于歌唱技巧的掌握程度的好坏。而对于《halo》这样一首非常火并且韵律又比较经典的一首英文歌我想每一个都会哼唱那么几句。无论是原唱碧昂丝还是后来翻唱的吉克隽逸都是我们广为知晓的明星，所以本篇论文就是借用了碧昂丝的《halo》为主要的研究对象，针对一些流行歌曲以及经典歌曲的演唱技巧以及演唱风格进行描写，并且在针对这样的描写可以找到所有流行音乐的共同点，从中找到一个适合未来流行音乐发展的演唱技巧以及演唱风格，并且引起所有的歌唱爱好者的关注。其实，对于一首好歌的演唱技巧是歌曲是否能红起来的关键问题所在，因此在论文的创作中会着重的描述歌手对于歌曲的演唱技巧的描写。 关键词：流行歌曲歌唱技巧歌唱风格
┊┊┊┊┊┊┊┊┊┊┊┊┊装┊┊┊┊┊订┊┊┊┊┊线┊┊┊┊┊┊┊┊┊┊┊┊┊ Abstract Each individual for the feel of the song may not be so strange, each song will bring you what are we hearing feeling for the important criteria for the assessment of a song is good or bad, is a measure of the degree of mastering the singer singing skills quality. But for the "halo" such a very fire and rhythm and comparison of the classic song English song and I think every one would hum so few words. Both the original singer Beyonce and cover jikejuan escape we are widely known star, so this paper is borrowed from Beyonce's "halo" as the main object of study, in view of some pop songs, classical songs singing skills and singing style in description, and according to this description can be found in common to all pop music, find a suitable for the development of future pop music singing skills and singing style from, and cause all the singing lovers attention. In fact, for a good song singing skills is the key to the problem whether the song to red, so emphatically in the thesis creation described in the singer for song singing skills description. Keywords：The skill of singing style of singing popular songs
公司部门及缩写中英对照
公司部门及缩写中英对照
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总公司HｅaｄＯffice 分公司Braｎch Office 营业部Buｓｉness Oｆfice 人事部Ｐersonnel Ｄｅｐartment 人力资源部HuｍaｎResouｒces Deｐartmenｔ总务部Ｇeneral Aｆｆaｉｒs Departｍeｎt 财务部General AccｏｕnｔinｇDepaｒtｍent 销售部Ｓales Dｅpaｒtmｅnt促销部SaleｓPromoｔioｎＤepartｍｅnｔ国际部Internatioｎal Deｐartmｅnｔ出口部Expｏｒt Deｐaｒｔmｅnt 进口部I ｍｐｏrｔDepａrtmenｔ?公共关系ＰｕｂｌiｃＲelations Departmenｔ广告部Ａｄverｔising Ｄeｐaｒtment 企划部Plａnning Department 产品开发部ProduｃｔDeveｌopｍent Ｄeｐarｔment研发部Reｓeａrc ｈand Dｅvelopmｅｎt Ｄepartmｅnｔ(Ｒ&D） 秘书室Secretarｉａl Ｐｏol 采购部PurｃｈaｓiｎｇDｅpaｒtｍent 工程部EｎgineerinｇDeparｔｍenｔ?行政部Admiｎ.Departmenｔ人力资源部HR Deparｔｍｅｎｔ市场部Marketｉng Dｅpartment?技术部Tｅchnolｏg Departｍｅnｔ客服部Ｓｅrｖice Depａrtment 行政部: Aｄｍinistratioｎ?财务部ＦｉnanciaｌＤepartment 总经理室、Diｒeｃotor, or P ｒesiｄenｔ 副总经理室、Depｕty Director, or Vice presｉdent 总经办、Gｅｎｅral Ｄｅparment 采购部、Pｕrchase & Order Dｅｐarｔｍｅｎt 工程部、Enginｅering Deparm ｅnt 研发部、Resｅarch Dｅparmｅnｔ 生产部、PｒｏducｔivｅDepartｍent销售部、Salｅs Ｄeｐａrmenｔ?拓展部ＢｕsineｓｓExｐｅnｄing Deｐａrｔｍent 物供部、Supply Dｅpartｍｅnt B&Ｄbｕsiｎeｓｓaｎd dｅvelopment 业务拓展部ＨＲ人力资源部Ａcｃoｕnｔ会计部ＰＲｐｅople ｒelａtioｎsｈip 公共关系部 OFC(Ｏffice，但不常见) / ＯMB ＝Offｉcｅof Ｍanageｍｅnt and Budget办公室Fiｎａｎce财务部?MKTG (Markeｔiｎg) 市场部R&D (R ｅsearcｈ&Dｅveｌopｍｅnt）研发部ＭFG (Ｍanufacturinｇ) 产品部AdｍｉnistraｔｉｏnＤeｐt. 管理部?Purｃhasｉｎg Dept 采购部Chａｉr ｍaｎ/ＰresidｅnｔＯffｉce /／Gｅrnerａl Manａｇeｒｏffiｃe or GM ｏffice 总经理办公室Mｏnitｏr& Suｐpｏrt Departmｅnt监事会Strategy Ｒｅsearｃｈ战略研究部?外销部: ＯｖerseaｓDｅｐａｒtmｅ nt,Intｅｒnatｉｏnal Sales Secｔiｏn,Export Sｅctiｏｎ?财务科:Financial／F ｉsｃａｌDepartment?会议室:ＭeetinｇRｏom／Hall／Auditorium，或C ｏnｆerencｅHａll／Aｕdiｔorium或直接Auditoriｕm, 会客室：Rｅceｐｔion Ｌounｇe/Room/Hｏuｓｅ,或Mｅeｔｉng Room或Ｇuest Room?质检科:Back－ｃheｃk Sectｉｏn／Ｄeｐａrtment,Qualｉty-insｐeｃｔiｏn/ＱuaｌitｙControl Deparｔment 内销部：DｏmesticＳａles Sｅcｔion/Dｅpartｍeｎt?厂长室:Miller/Dirｅctor/Ｐresideｎt'Ofｆiｃe( 这很取决于你们厂的类型和规模）?行政 科:AdministratiｏnＳeｃｔion/Departｍeｎｔ,Seｒvice secｔioｎ 技术部:TecｈｎologｙＳection 档案室:Arｃｈives(Ｏffice） 生产科:Productiｏn/Ｐrocｅssｉng Section
HALO 成就清单
HALO：Wars 战役模式：关卡 野猪兽屠夫Everything's Better with Bacon 战役第1关：用疣猪号冲撞50 名野猪兽沼气槽终结者Endless Fun 战役第2关：摧毁所有沼气槽 坠落的星盟Covenant "Hot Drop" 战役第3关：用光桥杀死至少5 个星盟单位 真正的赢家The Real Winner战役第4关：抢救亚当 劫持高手He's Got The Jack 战役第5关：劫持6 个星盟载具 犀牛保护者Rhino Hugger 战役第6关：成功保护所有犀牛号 直捣黄龙Micro Manager 战役第7关：不摧毁任何动力节点 巨象号步兵官Ramblin' Man 战役第8关：用巨象号训练100 队步兵 小憩片刻Sweet Naptime 战役第9关：同时让所有虫族聚落进入冬眠 慢条斯理The Procrastinator 战役第10关：干扰所有高压电塔的牵引光束 封住舱口Battened Down the Hatches 战役第11关：保护所有空气闸门 修理高手Handy with Tools 战役第12关：在 4 分钟内修复动力核心 圣甲虫号的骄傲Beaming with Pride 战役第13关：用圣甲虫号摧毁25 个单位 独立作战Didn't Get To Second Base 战役第14关：没有占领其它基地 按部就班Thinkin' about My Doorbell 战役第15关：依照顺序打开闸门 战役模式：秘密成就 会合佛吉军士Meet Sergeant Forge 以任何难度完成战役第1 关 冰雪战士Ice Warriors 以任何难度完成战役第1-3 关 波希之钥Key to Pirth以任何难度完成战役第4-7 关 丑陋的战争Ugly is only Skin Deep 以任何难度完成战役第8-11 关 漫漫长路No Way Home?以任何难度完成战役第12-15 关 战役模式：合作 相互扶持Backscratcher 合作完成任一战役任务 最佳拍档OMG BFF FTW 合作完成全部战役任务 战役模式：难度 神风烈士的判决Adjudicate the Arbiter完成英雄难度的战役游戏
英文加中文的网名
英文加中文的网名 英文加中文的网名 英文加中文的.网名 1、Feastaw离愁 2、Zing【生命力】 3、Guardianship相守 4、MySunshine我的阳光 5、〆゛丶yoyo 6、Hopeless（绝望） 7、DIE° 8、旧情话clot 9、Allure（诱惑） 10、▲角逐pursue 11、Shine（光芒） 12、傀儡Puppet▼ 13、shouldnot-溺宠（不该） 14、Overdoes【过分】 15、﹏Lostloveゝ 16、Monster怪兽 17、Sick°[病态] 18、eccentric°[怪人]
19、印象║Vicious 20、ERosIon腐朽 21、Despair（绝望） 22、Yoke（羁绊） 23、酷girl. 24、゛法式夕阳Romantic 25、◆◇sorrow°痕迹、 26、Enteral丶不朽 27、孽╮noone 28、Obsession【强迫症】 29、perpetual 30、Lonely孤独先生 31、Sunshine.? 32、baby公主 33、ゝxτяéмé° 34、Halo（光环） 35、分岛花音DeathSword* 36、乱祈°Amor▲ 37、disappear逃避 38、Winner（冠军） 39、Capital、魅魇 40、Devil（魔鬼）
41、simplelove［简单爱］ 42、False.虚假 43、。Ａliveㄣ 44、﹏heartbreaker° 45、Demonprincess（妖妃） 46、catastrophe浩劫。 47、Pull（难挽） 48、Pretext（借口） 49、_Edmundヾ 50、敷衍Continue\\\" 51、Schoolleave毕业生 52、Roselife（玫瑰人生） 53、Prevaricate（说谎） 54、Dislike（不喜） 55、aholic.（沉迷者） 56、Dear°心裂 57、call@ 58、温柔女Boss. 59、oo-┈→Danica℡~ 60、LuHan 61、Owetokiss 62、Moonlight月光
Halo Beyonce
【故事背景】 公元 2552 年，地球依然存在于银河系之中，但由于人口过剩的问题，让地球上的居民不得不前往开拓新的殖民地。当时超光速的飞行已经成为事实，让人们可以自由穿梭于星际之中，而地球上的联合政府也经由联合国太空指挥部 (the United Nations Space Command)，将转移权力重心至新开发之殖民地区。将近百万的地球人离开了地球，居住于太阳系中其它适合居住的星球上。Reach行星的开发，是人类殖民历史中重要的里程碑，也因此进而发展出供百姓使用的殖民拓荒宇宙飞船舰，以及供联合国太空指挥部 (UNSC) 军队使用之太空军舰，不但拉近了与地球的距离，Reach行星区也成为科技发展以及军事活动的中心。 三十二年前，与外星殖民活动是不被重视的；一支军事部队曾经执行过勘查任务，但几乎被消灭，只有一艘损坏严重的船舰返回 Reach 行星。幸存的船员叙述着外星舰队的恐怖攻击，可以轻易地将我方舰队摧毁，难以抵抗的种种经历。 这是人类与星盟的的第一次接触，而星盟的组成，是由许多外星种族因共同的宗教信仰聚集而成的。星盟的宗教长老认为，人类对天神有侮辱轻蔑之意，因而与人类展开战争，以圣战之名来驱离地球之人类。在经历过许许多多的大小战役，UNSC 的海军上将普雷斯顿?柯尔 (Preston Cole) 拟定了「柯尔草案」：任何船舰不得将星盟引至地球。当被迫撤离时，不能使用以地球为导航之撤离路线，也就是说，一旦遇到了危险攻击而遭俘虏时，所有船舰必须启动自毁装置已顾全大局。在 Reach 星球上进行着一项军事机密研究，就是创造出一系列基因强化战士的重大新发现。斯巴达二号 (SPARTAN II) 的基因强化战士在与星盟对战的测试中，留下令人印象深刻的纪录，但是却无法扭转战争的局势。
halo歌词
Beyonce - Halo 中英对照歌词 Remember those walls i built 还记得我一手搭建起的围墙吗？ Well baby they're tumbling down 好了，孩子，现在它们开始坍塌了 And they didn't even put up a fight 它们甚至无力抵抗 They didn't even make a sound 它们甚至还来不及做声 I found a way to let you in 我找到了让你进来的路 But i never really had a doubt 但是，我真的从没怀疑过你 Standing in the light of your halo 站在你光环的照耀下 I got my angel now 我找到了方向 It's like i've been awakened 我感觉好像已经觉醒了 Every rule i had you breakin' 你打破了我所有的规则 It's the risk that i'm takin' 我正在顶着这个风险 I ain't never gonna shut you out 我永远不会将你置之不理！Everywhere i'm looking now 无论我的视线停留在哪 I'm surrounded by your embrace 都被你的光辉环抱着 Baby i can see your halo 孩子，我能看到你的光环 You know you're my saving grace 你知道你就是我的恩赐 You're everything i need and more 你超过我所需要的一切 It's written all over your face 这些都写在了你的脸上 Baby i can feel your halo 孩子，我能感觉到你的光环 Pray it won't fade away 祈祷它永不凋零吧 I can feel your halo (halo) halo 我能感觉你的光芒 I can see your halo (halo) halo 我能理解你的光芒 I can feel your halo (halo) halo 我能感觉你的光芒 I can see your halo (halo) halo 我能理解你的光芒 Hit me like a ray of sun 像一束阳光一样投向我吧 Burning through my darkest night 燃尽我最漆黑的夜晚 You're the only one that i want 你就是我唯一需要的人 Think i'm addicted to your light 我想我已被你的光芒折服 I swore i'd never fall again我曾发誓我不会再一次屈服 But this don't even feel like falling 但是，这一次感觉像是彻底崩塌了Gravity can't forget 重力并没忘记 To pull me to the ground again 将我再次拉回地面 Feels like i've been awakened 我感觉好像已经觉醒了 Every rule i had you breakin' 你打破了我所有的规则 The risk that i'm takin' 我正在顶着这个风险 I'm never gonna shut you out 我不会将你置之不理的 Everywhere i'm looking now 无论我的视线停留在哪 I'm surrounded by your embrace 都被你的光辉环抱着 Baby i can see your halo 孩子，我能看到你的光环 You know you're my saving grace 你知道你就是我的恩赐 You're everything i need and more 你超过我所需要的一切 It's written all over your face 这些都写在了你的脸上
Halo 歌词中英对照
Remember those walls I built? Well, baby they are tumbling down And they didn't even put up a fight They didn't even make a sound I found a way to let you in But, I never really had a doubt Standing in the light of your halo I got my angel now It's like I've been awakened Every rule I had, you break it It's the risk that I'm taking I ain't never gonna shut you out! Everywhere I'm looking now I'm surrounded by your embrace Baby, I can see your halo Y ou know you're my saving grace Y ou're everything I need and more It's written all over your face Baby, I can feel your halo Pray it won't fade away I can feel your halo I can see your halo I can feel your halo I can see your halo Halo, ooh ooh..... Hit me like a ray of sun Burning through my darkest night Y ou're the only one that I want Think I'm addicted to your light I swore I'd never fall again But this don't even feel like falling Gravity can't forget To pull me back to the ground again It's like I've been awakened Every rule I had, you break it It's the risk that I'm taking I'm never gonna shut you out! Everywhere I'm looking now
XBOX360大作
HALO 3、ODST、致远星战争机器1、2、3（前几天出的）洞穴2（港正版写的英文其实有中文） 光环战争 心灵杀手 失落的奥德赛蓝龙 神鬼寓言2、3 忍龙2 PGR4 极限竞速3、4（下月）极品飞车系列（除了15） Kinect:养动物那个不知道叫什么、大冒险、运动会、逍遥赛车、型可塑（首发写的中文没中文，只有图案是中间站一女的那是中文的） 能想起来的目前就这么多 据说巫师2也有中文XB版最近没啥新消息 足球啥的运动类的不了解 XBOX360第一方游戏基本都有中文版 光环3、光环致远星、光环3ODST、光环战争、战争机器1、战争机器2、神鬼寓言2、神鬼寓言3、生化危机5汉化、刺客信条2汉化、刺客信条兄弟会汉化、真三国无双5、真三国无双5帝国等等 我手里现在有忍龙2、HALO3、孤岛危机2、皇牌空战、使命8、生化5 鬼泣4玩过战地3 战争机器系列我都知道 还有哪些大作呢高手作答 你所说的是独占大作吧。全平台的也包括的话就很多了。先说独占： 1，首先你的HALO3。Halo系列xbox360上有本传，天降神兵，还有致远星3作。剧情紧密，环环相扣。建议一步步玩，过几天还有一代的复刻版上市，建议你也玩玩，绝对不容错过。 2，战争机器3作，我想你肯定已经玩了，忍龙系列xbox360上只有2，有机会可以玩一下一代。 3，神鬼寓言系列，有官方中文版，绝对建议玩一下。 4，最终幻想也有中文版但是锁区，有机会可以买来玩玩。极限竞速系列是赛车的，xbox360上必玩赛车游戏，车型非常之多，手感比较真实。推荐！ 5，还有，如果爱玩RPG类的话，失落的奥德赛和蓝龙是你必须入手的游戏。6，还有诸如，鬼屋魔影，心灵杀手，丧尸围城系列，星宵传说。 如果加上你所说的全平台的话，除了你列出来的，还有蝙蝠侠，三国无双，生存之路，质量效应系列，古墓丽影系列，波斯王子系列，辐射系列。 刺客信条系列，我强烈推荐。非常好。 还有很多系列，暂时不推荐了。因为实在太多。有的一时也想不起来。 希望可以帮助你，所有家用机玩家共勉。 1、神鬼寓言系列 2、九十九夜2 3、最终幻想13 4、蓝龙 5、心灵杀手 6、光环系列 7、波斯王子系列 8、丧尸围城2 9、无双联合突击和6
Halo Tag
性能参数 产品名称：Halo Tag? TMR Ligand 英文名称：Halo Tag? TMR Ligand 产品货号：G8251 产品规格：promega 产品产地：USA 产品商标：promega 价格：4768元 产品资料：实验方法技术资料 更新时间：2014-11-18 19:05:00 浏览人数：392 上海前尘生物科技有限公司 Halo Tag? TMR Ligand HaloTag? Interchangeable Labeling Technology(a,b,c)(HaloTag?可交换标记技术)是一种用于表达HaloTag?蛋白或融合蛋白的活细胞或固定的哺乳动物细胞成像的新型工具，可用来分析标记融合蛋白的翻译后修饰，并用于分离蛋白质及蛋白复合物。该技术以报告蛋白与其配基之间形成高效的共价键为基础，报告蛋白是经过特别设计的，由HaloTag? pHT2(a,b,c)载体或pFC8A及pFC8K (HaloTag?) CMVFlexi?载体编码(a-d)；这种共价结合可以发生在活细胞内、溶液内，或在固相支持物上。HaloTag?载体包含有HaloTag?蛋白的开放阅读框(ORF)，是一种水解酶基因的基因工程衍生物。对于哺乳动物细胞来说，HaloTa g?蛋白无内源性表达，使得其标记具有高特异性。H aloTag?配基(a,b,c) 可支持多种功能，包括荧光标记，亲和处理，并可粘附于固相上。在一般的生理条件下，共价键可迅速形成，具有高度的特异性，该反应基本不可逆，其产生的复合物即使在严苛条件下也能保持稳定。该技术的开放式设计可适用于不同的配基。目前，我们提供可穿透细胞膜的、分别带有红色、绿色或蓝色荧光标记物质的配基，以及穿膜能力不同的2种生物素配基。HaloLinkTMResin (b) (Cat.# G1911)是一种固相支持物，可使HaloTag?融合蛋白直接粘附于Sepharose?表面。 注意：pFC8A、pFC8K(HaloTag?)CMV Flexi? Vectors的更多信息，请参考操作手册#TM254。特点 ?在液相或固体支持物上标记：HaloTag?配基与HaloTag?蛋白或融合蛋白以高特异性及亲和力结合。 ?在活细胞中标记HaloTag?蛋白：HaloTag? TMR、diAcFAM、***(Coumarin)和生物素配基易于跨过细胞膜。 ?Pull Down蛋白复合物：HaloTag? PEG-Biotin Ligand(HaloTag? PEG-生物素配基)上的间隔基(Spacer)和反应接头具有理想的Pull Down能力。或者，可以直接用HaloLinkTM 树脂PullDown。 ?使固定细胞成像：共价键十分稳定，可以使固定细胞成像，并分析极端环境中的标记蛋白。 ?引进新功能或实现连续标记：此技术的开放式结构能实现针对多种应用使用不同的配基。 ?对多重实验只需设计一种遗传构造：通过使用不同的HaloTag?配基能获得新的功能，而无需设计和克隆新的表达结构。 ?能使用SDS-PAGE质谱等技术分析标记的融合蛋白：结合的配基在变性环境中依然稳定。应用
电影《毕业生》歌词
《毕业生》歌词大意 这歌是保罗西蒙和加芬克尔唱的，后来Sarah Brightman也唱过。 1、The Sound of Silence 寂静之声 Hello darkness, my old friend 你好黑暗我的老朋友 I've come to talk with you again 我又来和你交谈 Because a vision softly creeping 因为有一种幻觉正向悄悄地向我袭来 Left its seeds while I was sleeping 在我熟睡的时候留下了它的种子 And the vision that was planted in my brain 这种幻觉在我的脑海里生根发芽 Still remains 缠绕着我 Within the sound of silence 伴随着寂静的声音 In restless dreams I walked alone 在不安的梦幻中我独自行走 Narrow streets of cobblestone 狭窄的鹅卵石街道 'Neath the halo of a street lamp 在路灯的光环照耀下 I turned my collar to the cold and damp 我竖起衣领抵御严寒和潮湿 When my eyes were stabbed by the flash of a neon light 一道耀眼的霓虹灯光刺入我的眼睛That split the night 它划破夜空 And touched the sound of silence 触摸着寂静的声音 And in the naked light I saw 在炫目的灯光下 Ten thousand people, maybe more 我看见成千上万的人 People talking without speaking 人们说而不言 People hearing without listening 听而不闻 People writing songs that voices never share 人们创造歌曲却唱不出声来 And no one dare disturb the sound of silence 没有人敢打扰这寂静的声音 "Fools" said I, "You do not know 我说：“傻瓜，难道你不知道 Silence like a cancer grows” 寂静如同顽疾滋长” Hear my words that I might teach you 听我对你说的有益的话 Take my arms that I might reach to you 拉住我伸给你的手 But my words like silent as raindrops fell 但是我的话犹如雨滴飘落 And echoed in the wells of silence 在寂静的水井中回响 And the people bowed and prayed to the neon god they made. 人们向自己创造的霓虹之神鞠躬祈祷 And the sign flashed out its warning 神光中闪射出告诫的语句 And the words that it was forming 在字里行间指明 And the sign said: 它告诉人们 "The words of the prophets are written on the subway walls 预言者的话都已写在地铁的墙上and tenement halls 和房屋的大厅里 And whispered in the sound of silence." 在寂静的声音里低语
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PCB术语中英文对照表.doc
Adhesion 附着力 Annular Ring 孔环 AOI（ automatic optical inspection ）自动光学检测 AQL（ acceptable quality level ）可接受的质量等级 B²it(buried bump interconnection technology) 埋入凸块焊点互连技术 BBH(buried blind hole) 埋盲孔 BGA(ball grid array) 球栅阵列 Blister 起泡 Board Edges 板边 Burr 毛头 / 毛刺 BUM(Build-up multilayer) 积层式多层板 BVH（ buried/blind via hole ）埋 / 盲导通孔 CAD(computer aided design) 计算机辅助设计 CAM(computer aided manufacturing) 计算机辅助制造 Carbon oil 碳油 CEM(composite epoxy material) 环氧树脂复合板材 chamfer 倒角 Characteristic impedance 特性阻抗 CNC（ computerized numerical control ）计算机化数字控制 Conductor Crack 导体破裂 Conductor Spacing 导线间距 connector 连接器 Copper foil 铜箔（皮） Crazing 微裂纹 ( 白斑 ) Delamination 分层 Dewetting半润湿 ( 缩锡 )
DFM（ design for manufacturing ）可制造性设计 DIP(dual in-line package) 双列直插式组件 Dk（ dielectric constant ）介电常数 DRC(design rule checking) 设计规则检查 drawing 图纸 ECN(engineering change notice) 工程更改通知 ECO(engineering change order) 工程更改指令 E glass 电子级玻璃 entek OSP处理 Epoxy resin 环氧树脂 ESD(electrostatic discharge) 静电释放 Etched Marking 蚀刻标记 Flatness 翘曲度 Foreign Inclusion 外来夹杂物 Flame resistant 阻燃性 FR-2(flame-retardant 2) 耐燃酚醛纸基板 FR-3(flame-retardant 3) 耐燃环氧纸基板 FR-4(flame-retardant 4) 耐燃环氧玻璃布基板 FR-5(flame-retardant 5) 耐燃多功能环氧玻璃布基板ground 地面（层） Haloing 晕圈 HDI(high density interconnection) 高密度互连技术HASL(hot air solder leveling) 热风焊料整平（整平）IC(integrated circuits) 集成电路 Ink Stamped Marking 盖印标记 Insulation resistance绝缘电阻
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