New D=4 gauged supergravities from N=4 orientifolds with fluxes
新视野大学英语读写教程4Unit1单词和例句
新视野大学英语读写教程4Unit 1 （Section A）1. chase vt. 追逐追赶My dog likes chasing rabbits.我的那条狗喜欢追逐兔子。
2. cruelty n. 残酷残忍The book tells readers the cruelty of the slave trade at that time.这本书告诉了读者在那个时候奴隶买卖的残忍。
3. pessimistic adj. 悲观的The tone of the meeting was very pessimistic.该会议的气氛非常悲观。
The doctors are pessimistic about his chances of recovery.医生们对他康复的可能性感到悲观。
4. conquest [U] 征服控制攻占The conquest of inflation has been the Government’s economic priority.控制通货膨胀一直是政府经济工作的重点。
He finally made the conquest of the disease come true.他最后战胜了那疾病。
The empire had expanded largely through military conquest.帝国的扩张主要是通过军事占领。
5. bankrupt adj. 破产的The company was declared bankrupt.这家公司被宣布破产。
Five years ago she was a successful actress, but now she is bankrupt.五年前她是一个成功的演员，可是现在她一贫如洗了。
6. motive n. 动机Why would she have killed him? She has no motive.她为什么会杀他呢？她没有任何动机。
Continued fraction solution to the Raman interaction of a trapped ultracold ion with two tr
a rXiv:q uant-ph/01285v117D ec2Continued fraction solution to the Raman interaction of a trapped ultracold ion with two traveling wave lasers Mang Feng 1Max-Planck Institute for the Physics of Complex Systems,N ¨o thnitzer Street 38,01187Dresden,Germany 2Laboratory of Magnetic Resonance and Atomic and Molecular Physics,Wuhan Institute of Physics and Mathematics,Academia Sinica,Wuhan 430071People’s Republic of China (February 1,2008)Abstract Raman interaction of a trapped ultracold ion with two traveling wave lasers has been used extensively in the ion trap experiments.We solve this interaction in the absence of the rotating wave approximation by a continued fraction,without considering the restriction of the Lamb-Dicke limit and the weak excitation regime.Some interesting characteristics of the ion-trap sys-tem,particularly for the ion outside the weak excitation regime are found.Finally,a comparison of our results with the solution under the rotating waveapproximation is made.PACS numbers:42.50.DV,32.60.+iTypeset using REVT E XQuantum effects in the motion of trapped ultracold ions have been drawn much attention in recent years since the success that a single ultracold ion was confined in the ground state of a Paul trap[1].Considerable progress has been made so far,such as the preparation and measurement of various nonclassical states[2],and two qubits logic gate operation[3],which are of great current interest in ion trap experiment.It has been proven that a trapped ultracold ion experiencing laser waves can be described by the Jaynes-Cummings model(JCM)[4]under the rotating wave approximation(RWA). The JCM,describing a two-level system coupled to a harmonic oscillator under RWA in the case of near resonance and weak coupling,has successfully dealt with the cavity QED problems,in which a two-level atom interacts with a monochromatic cavity mode with the form of harmonic oscillator.In the trapped ion configuration,the ion is simplified to be two levels and supposed to move within the region of the space much smaller than the effective wavelength of the laser wave(Lamb-Dicke limit),the vibrational level of the trap is quantized as the harmonic oscillator,and the laser radiating the ion is generally supposed as the classical form of a standing or traveling wave.Different from the situation of cavity QED,the strength of the coupling between the ion and the oscillator can be conveniently adjusted simply by changing the intensity of the laser.For example,in the strong excitation regime[5,6,8],the coupling constant,denoted by Rabi frequency,is larger than the trapping frequency,which makes RWA no longer valid.Under RWA,along with the assumption that the ion is confined within the Lamb-Dicke limit(LDL)and weak excitation regime(i.e.,the Rabi frequency being smaller than the trapping frequency),one may easily obtain three simple cases[4,6],that is,carrier excitation, red detuning and blue detuning.If excluding the supposition with respect to the LDL and weak excitation regime,Vogel and his coworkers gave a standard approach to such a nonlinear JC model[7].However,in case the RWA is excluded,the ion trap problem turns to be non-integrable,whose solutions have to be obtained completely by the numerical calculation[6,8]. Recently,we analytically treated[9]the interaction in the absence of RWA between a standing wave laser and a trapped ultracold ion in coherent state representation[10,11].Althoughthose analytical results are only some particular solutions to the problem,some important information neglected in former works due to use of RWA were presented.However,our investigation in that work was only under both the weak excitation regime and the LDL. Moreover,the solutions in that work strongly depended on the truncation of the series, and thereby the deduction and the forms of the analytical expressions went tedious with the increase of the number of terms in the series,which makes it hard to obtain the eigenenergies and eigenfunctions rapidly at our disposal.Furthermore,it is Raman configurations that are usually applied in actual ion trap experiments for the interaction between lasers and ions,instead of the simple case described in Ref.[9].Therefore,in this contribution,we choose RamanΛ-type configuration(shown in Fig.1)for a study,which corresponds to the actual process in the NIST experiments[1].To present a more general description for such a model,we will exclude the assumption related to both the weak excitation regime and LDL by means of some unitary transformations.Moreover,to overcome the difficulty of complicated analytical deduction,our solution will resort to a continued fraction,from which the eigenenergies of the system and the coefficients of the series of the eigenfunctions can be rapidly obtained by numerical calculation.Fig.1describes the interaction of a trapped ultracold ion with two off-resonant counter-propagating traveling wave lasers with frequenciesω1andω2respectively.Both laser beams are assumed to propagate along the x axis,and the problem is thereby one-dimensional. For a sufficiently large detuningδ,the third level|r>may be adiabatically eliminated,and we face an effective two-level system,in which the lasers drive the electric-dipole forbidden transition|g>↔|e>.In the frame rotating with the effective laser frequencyωL(=ω1−ω2), the dimensionless Hamiltonian of this system is[1,2,12]H=∆2(σ+e iηˆx+σ−e−iηˆx)(1)where∆=(ω0−ωL)/νwithω0being the resonant frequency of the two levels of the ion,andνbeing the trap frequency.Ωis the dimensionless Rabi frequency andηthe Lamb-Dicke parameter.σi(i=±,z)are Pauli operators,ˆx=a++a is the dimensionlessposition operator of the ion with a+and a being operators of creation and annihilation of the phononfield,respectively.The notations’+’and’-’in front of iηˆx indicate that the laser wave propagates towards x and-x directions,respectively.νis generally supposed to be much greater than the atomic decay rate(strong confinement limit)for neglecting the effect of the atomic decay.Wefirst perform some unitary transformations on Eq.(1)[12],and obtainH I=UHU+=Ω√dα,and rewrite Eq.(2)in coherent state representation,that is,H=Ωdα+g(α+d2πiexp(−|α|2)|α∗><α∗|=1.The eigenfunctionof the Schr¨o dinger equation of Eq.(3)can be supposed to beΨ(α)= Ψ1(α)Ψ2(α) ,and the eigenenergy is E.Thus we have(α+g)d2Φ2,(4)(α−g)d2Φ1(5)where we have made a transformationΦ1=Ψ1(α)+Ψ2(α)andΦ2=Ψ1(α)−Ψ2(α).To solve Eqs.(4)and(5),we orderξ=α+g,andΦ1=exp(−gξ)φ(ξ).Combining Eq.(4)with Eq.(5)will yield a second-order differential equationξ(ξ−2g)d2dξφ+[E2−ǫ2−Ω2By supposingφto be a series formφ= ∞n=0C nξn,Eq.(6)becomes a recurrence relation about the coefficient C nαn C n+1+βn C n+γn C n−1=0(7) whereαn=2g(n+1)(E−ǫ−1−n),βn=[n2+2n(2g2−E)+E2−ǫ2−Ω2βn−1−γn−1αn−2β1−γ1α0/β0=αnγn+1βn+2−αn+2γn+32σz+αdΩ2detunings.In view of physics,the only reasonable explanation for this case is that the in-teraction between the laser and the ion plays main role in the system.With the increase of the detuning,this interaction goes weaker and weaker.Therefore,although the energy of the ion itself is enhanced with the increase ofη,the energy of the total system remains nearly constant;(iii)Fig.4presents the relation betweenΩand∆for certain values of E andη.From the forms of the curves,we may guess that the relation among E,∆,ηandΩis of the form of Ω=f(E)[1−h(η)∆2]with f(E)and h(η)being positive definition functions of E andη, respectively.Moreover,from the specific calculation,we found that,for a certainΩ,with the increase ofη,the convergence of C n would get worse and worse,particularly for the large detuning case.But the larger the value ofΩ,the larger the value ofηfor satisfying the convergence of C n.The problem with respect to the convergence will be discussed physically later.Returning Eqs.(4)and(5),we canfind thatΦ1=exp(gξ)φis another solution for ξ=α+g.Repeating above deduction,we will obtain Eq.(8),whereas in this case,αn= 2g(n+1)(E−1−ǫ−n),βn=(n2−2nE−4ng2+E2−ǫ2−Ω2Ω ∞n=0(n−E+ǫ)C n(α+g)n e±g(α+g).Therefore,the eigenfunction of the system isΨ(α)= Ψ1(α)Ψ2(α) =1Ω(n−E+ǫ)](α+g)n∞n=0C n[1+2|n>= dαdα∗√2σz+αd2 AB∞n=0C nαn(11)where A=1±2Ω2Ω,B=1∓2Ω2Ω.Then the eigenfunction in theoriginal representation isΨSO(α)=12e iπa+a/2 11−11 1√Ω±2Ω2presented the solutions in the weak excitation regime for the case of near-resonance.In our treatment,however,the numerical solution is made based on the continued fraction,which is obtained in the coherent state representation.So our solution is still valid even for the large detuning and strong excitation regime.Before ending our discussion,it is interesting to make a comparison between our solution with those under RWA.In general,we may solve Eq.(1)by means of nonlinear JC model as proposed in[7]for the ion governed outside the weak excitation regime.However,to make the comparison easily and obviously,we start our comparison procedure from Eq.(2).By)t]on Eq.(2),we can obtain E±n= performing a unitary transformation exp[−i(Ω22n+1η2±14η2(n+1)+1(n=0,1,2,···)in the Fock state representation forΩ=2 4under RWA(see Figs.8).From Figs.3,6and8,we see that,for small values ofη,the case of n=2under RWA is similar to those ofΩ=2in Figs.3and6,where E+n and E−n are similar respectively to the very large and zero detuning cases without RWA.Although both the solutions with RWA and without RWA include multi-curve,the difference is obvious:as it is merely a particular solution,the solution without RWA approaches to the solution of a certain excited state under RWA.On the other hand,as RWA merely retains some resonance terms in Hamiltonian,the solution under RWA is irrelative to the variation of∆and just related to a specific value ofΩ.Moreover,as they are obtained from the solution of Eq.(8), the results without RWA are restricted by the convergence of the coefficients of the series.In contrast,there is no restriction mathematically for the expressions of the solution under RWA even in the case ofη→∞.However,in physics,ηis impossible to approach to infinity for a ultracold ion system,and it must be cut offat a certain value.Therefore,in this sense,the convergence condition in our solution of the continued fraction provides a physical restriction on thefinal results,which plays the same role as the restricted condition for the solutions in)t]and Ref.[9].Furthermore,further deduction with the transformations exp[−i(Ω4exp[−i(Ω)t]performed on Eq.(2)respectively can tell us that,with the increase of 6Ωandη,the difference between the solutions with RWA and without RWA will be larger and larger.In summary,we have presented a continued fraction solution to a trapped and laser-radiated ultracold ion experiencing two traveling wave lasers in a Raman process in the absence of RWA.Instead of the complicated and tedious analytical forms in Ref.[9],we can solve the problem rapidly from the continued fraction and present more complete information of the system,such as the relation among E,Ω,∆andη.As limitation of weak excitation regime and LDL as well as RWA is excluded in our treatment,our solution is not only exact, but more general.It can be used to investigate quantum properties of the ion-trap system in a wider range of parameters,and serve as a comparison with other approximate works, as we did in Ref.[16].However,as Eq.(2)represents a kind of typical non-integrable system, our solutions are still only some particular ones.While in comparison with former solutions under RWA,we still found some interesting results,particularly for the case outside the weak excitation regime and LDL.We should emphasize that,it is hard to carry out the trapped ion-laser interaction experimentally outside the weak excitation regime at present due to the requirement of very high intensity of the laser,and the laser cooling to the ground state of the trapping potential has not been reported yet in this regime.Therefore,we hope the solution in our work would be helpful for the future exploration of the quantum properties of the ion-trap system in this respect.The work is partly supported by National Natural Science Foundation of China under Grant No.19904013.Note added:after accomplishing this paper,the author becomes aware of that a work[17] related to the fast quantum gate for cold trapped ions has been carried out based on Ref.[12] and the treatment similar to our RWA treatment.REFERENCES[1]Diedrich F,Bergquist J C,Itano W M,and Wineland D J,Phys.Rev.Lett.62(1989)403;Monroe C,King B E,Jefferts S R,Itano W M,Wineland D J,Goulkd P,Phys.Rev.Lett.75(1995)4011.[2]Meekhof D M,Monroe C,King B E,Itano W M,Wineland D J,Phys.Rev.Lett.76(1996)1796;Monroe C,Meekhof D M,King B E and Wineland D J,Science, 272(1996)1131.[3]Monroe C,Meekhof D M,King B E,Itano W M,Wineland D J,Phys.Rev.Lett.75(1995)4714.[4]Jaynes E T and Cummings F W,Proc.IEEE,51(1963)89;Blockley C A,Walls D F,Risken H,Europhys.Lett.17(1992)509;Cirac J I,Parkins A S,Blatt R,and Zoller P, Phys.Rev.Lett.70(1993)556;mun.97(1993)353;Cirac J I,Blatt R,Parkins A S,and Zoller P,Phys.Rev.Lett.70(1993)762.[5]Poyatos J F,Cirac J I,Blatt R and Zoller P,Phys.Rev.A54(1996)1532.[6]Cirac J I,Parkins A S,Blatt R,and Zoller P,Adv.Atom.Mole.Opti.Phys.V37(1996)237.[7]Vogel W and Filho R L de M,Phys.Rev.A52(1995)4214;Filho R L de M and VogelW,Phys.Rev.Lett.,76(1996)608.[8]Zeng H,Lin F,Wang Y and Segawa Y,Phys.Rev.A59(1999)4589.[9]Feng M,Zhu X,Fang X,Yan M and Shi L,J.Phys.B32(1999)701.[10]Negele J W and Orland H,Quantum Many-Particle Systems(Addison-Wesley,Reading,1987)20.[11]Ku`s M and Lewenstein M,J.Phys.A19(1986)305.[12]Moya-Cessa H,Vidiella-Barranco A,Roversi J A,Freitas D S and Dutra S M,Phys.Rev.A59(1999)2518[13]Feng M,Fang X,Duan Y,Zhu X,and Shi L,Phys.Lett.A244(1998)18.[14]Plata J and Llorente J M G,Phys.Rev.A48(1993)782.[15]Feng M,Fang X,Shi L,Zhu X and Yan M,Commun.Theor.Phys.31(1999)175.[16]Qin G,Wang K,Li T,Han R and Feng M,Phys.Lett.A239(1998)272.[17]Jonathan D,Plenio M B and Knight P L,Phys.Rev.A62,(2000)042307Captions of thefiguresFig.1Level scheme of the internal structure of the trapped ultracold ion,where|g>↔|e>is dipole forbidden.Fig.2Variation of E with respect to∆in the case ofΦ1=exp(−gξ)φ,where the dotted,dashed,solid and dash-dotted curves representη=0.2,0.4,0.6and0.8,respectively. For clarity of thefigure,we only plot the cases forΩ=2,4and6.Fig.3Variation of E with respect toηin the case ofΦ1=exp(−gξ)φ,where the solid, dotted,dash-dotted and dashed curves represent∆=0.2,1.6,2.0and3.0,respectively.For clarity of thefigure,we only plot the cases forΩ=2,4and6.Fig.4Variation ofΩwith respect to∆in the case ofΦ1=exp(−gξ)φ,where the solid, dashed and dotted curves representη=0.02,0.4and0.6,respectively.We only plot the cases for E=3and5.Fig.5Variation of E with respect to∆in the case ofΦ1=exp(gξ)φ.The rest are the same as that in Fig.2.Fig.6Variation of E with respect toηin the case ofΦ1=exp(gξ)φ.The rest are the same as that in Fig.3.Fig.7Variation ofΩwith respect to∆in the case ofΦ1=exp(gξ)φ.The rest are the same as that in Fig.4.Fig.8Variation of E±n with respect toηforΩ=2for the solution under RWA.See text.11|r>δ2ω1ωω∆Fig.1|e>|g>。
新视野大学英语4 第三版读写教程 第二单元答案(B4U2)
1. How do you understand the sentence "No amount of rehearsal will help you come up with the right answer" (Para. 2)?Reference:The sentence means that it is very difficult, or even impossible, for a man to give a right answer when a woman asks him how she looks, no matter how hard he thinks about it and how many different answers he tries.2. According to the text, in what way do men and women evaluate their appearance differently?Reference:Men are satisfied with being average-looking, paying little attention to their looks. In contrast, women pay great attention to their body and image, considering their appearance as not good enough even if they are in fact attractive.3. What causes women to be always dissatisfied with their looks?Reference:The interaction of many psychological and societal factors, for example, their childhood experiences with toys, and the influence of the media.4. In what way do the toys girls play with differ from those boys play with?Reference:Girls' toys are proportioned to have extreme measures of the body (e.g. in terms of height, weight and waist size), whereas boys' toys can look weird rather than handsome.5. What does the sentence "You could not imagine him saying to the others, ‘Is this accessory the right shade of violet for this outfit?'" (Para. 6) imply?Reference:It implies that men pay little attention to the details of their appearance.6. Why is the supermodel Cindy Crawford mentioned in Paragraph 7?Reference:Cindy Crawford is mentioned as an example to show that the beauty industry and the media have great influence on women's devotion to physical beauty and the use of beauty products.7. What is the author's attitude toward the claim that women care much about their appearance due to pressure from men?Reference:The author thinks that the claim is not right since men in fact pay little attention to the details of women's appearance.8. Why do women think that men are not qualified to judge whether a woman looks good or not?Reference:Women think so because men do not even care about their own appearance. For instance, a man often does not bother to clean the cream in his hair or ears after shaving.1. What are the factors that make women pay much greater attention to their appearance than do men?Reference:I think there are three main factors accounting for women's greater attention to appearance. The first are cultural traditions. It is common in many cultures that people put high value on beauty when they look at women. The second is the requirement of certain jobs. For example, in China airline companies set certain criteria for appearance (e.g. in terms of height and weight) when they recruit stewards and stewardesses. Finally, the influence of the media is another strong factor which shapes women's pursuit of physical beauty. There are a lot of advertisements of cosmetics and skincare products in various media such as TV, magazines and newspapers. They often havecelebrities as the spokesperson for the advertised products, which makes women have an illusion that they could look as good as those famous stars if they use the products. In short, these three factors exert immense influence on how women value appearance.2. Are there any occasions in life where it is necessary for a person, either a woman or a man, to look good? Why or why not?Reference:• Yes. On certain formal occasions, a person, either female or male, has to pay attention to his attire. Sample cases are job interviews, business meetings, weddings, and banquets. This is because to dress properly is an important element of successful completion of these events.• No. People do not have to care what others think of them as long as they feel comfortable and satisfied with their looks themselves. After all, this is the most important source of happiness to people.3. What do you consider as the most important traits that make a person beautiful?Reference:In my opinion, the important traits of human beauty include two types, one for appearance and one for inner qualities. Features that characterize a beautiful appearance are a good-looking body, proper clothes and accessories, as well as use of makeup that matches the occasion or event one is attending. Inner qualities that make a person beautiful mainly include good manners and positive personality traits such as honesty, bravery or friendliness.4. What do you think of the relationship between wearing makeup and female beauty? In other words, do women have to apply cosmetics in order to look beautiful? Why or why not?Reference:• Yes. Women should pay great attention to their appearance and hence need to wear makeup. This is because beauty is, believe it or not, usually an important quality for women to succeed, for example, when they want to look for a job or an ideal husband.• No. What really makes a person beautiful is inner beauty rather than physical appearance. A beautiful look can't last long, but inner beauty, for example, intelligence and honesty, may make a person successful and happy throughout his life.5. If you were the head of a cosmetics company, how would you market or promote a new product?Reference:I would market a new product by three means. First, I can ask a celebrity, for example a famous movie star or a supermodel, to be the brand spokesperson on TV. This is a common practice in the advertising industry, and I think it is very effective. Second, I will hire people to distribute flyers and give away free samples of the product on the streets, so the product can reach potential customers directly. In addition, I may post advertisements on public transportation vehicles such as buses and subways. In this way, the commercials can be seen by a large number of people.Fill in the blanks with the words given below. Change the form where necessary. Each word can be used only once.Done with this activity. Time submitted: 2017-03-07 21:43 (Tuesday)Your score: 0%1.We need to improve the quality of education so that our children willnot leave school (deficient)in literary and reasoning skills.2.In a society governed by the rule of law, every citizen is subjectto possible (prosecution)if he violates the law.3.The pay gap between average workers and top corporate officers hasled to pubic (outrage)as executives receive large packages despite falling share prices.4.The delicious meal (appeased)our hunger and made us feel warmagain after having walked in the snow all day.5.The military insists on (conformity)in many areas, forexample, dress and haircut, with the primary objective of promoting group unity.6.My daughter used to play with the dog by taking a(n)(strand)of its hair and then spending a long time rubbing, combing and twisting it.7.When she left for the party, she took great care to make her necklaceand shoes (complement)her dress.8.It was necessary to provide living places for(transient)immigrants passing through the area on their way to more permanent dwellings.9.They had just moved in, so they needed to buy a number of kitchen(appliances), including a microwave oven, a toaster, and a coffee maker.10.She wanted a beautiful and elegant (outfit)to attend thewedding of a friend, but couldn't find anything satisfactory in the nearby shops.Add-ion,-er,or-ist to or remove them from the following words to form new words.For each blank you can only fill in one word.Correct answerdominationorientationconfrontationcomposerbinderscannermanufacturereraseimperialistleftistterroristhumanistFill in the blanks with the newly formed words. Change the form where necessary. Each word can be used only once.1. The Internet challenges the (domination) of traditional media such asnewspapers and television as the main sources of news in modern society.2. Some scientists warn that the X-ray (scanners) now being used toscreen passengers at many airports may be harmful to the human body.3. Many people think that a(n) (humanist) should have very strongmorals, in addition to beliefs in a philosophy that focuses on human values and concerns.4. The police interviewed all six witnesses, but none of them could describeclearly how the (confrontation) began and who opened fire first.5. In politics, (leftists) are people who generally support social changesto create a more equal society and show concern for those who sufferdisadvantages.6. A study of mid-level administrators' career (orientation) showed thatmany of these managers view their current position as a temporary step on an upward path.7. The idea that the United States is a melting pot implies that racialdifferences are to be (erased)and that immigrants should give up their own cultural traditions.8. Effective measures should be taken to prevent (terrorists) fromattacking civilians, people who have no power to defend themselves from bombs and guns.9. Toyota is one of the world's largest (manufacturers) of cars, withmore than 50 plants across the globe outside Japan.10. He sent his parents some of his recent news articles in a(n) (binder) ,arranged according to their publication dates.11. This island became a colony after European (imperialists) decided touse it as their trading port in the 19th century.12. The concert to be held next month promotes music by(composers) from Africa and South America.Drag 10 words from the list to their proper places to complete the passage. Each word can be used only once.Double click on a particular blank to reset it if necessary.I was once in a relationship with a woman who was the most brilliant, creative and driven person I'd ever known. I told her these things often because she didn't see herself this way, despite (1)(achieving) great success and acclaim (称赞) in her professional field. She was also (2)(gorgeous) and sexy, though she seemed not to realize this either, so I told her these things too. But while I thought it was more important to praise her brilliance, it seemed to mean more to her that she was (3)(considered) attractive.My experience with this girlfriend exemplifies a common phenomenon in life —when it comes to complimenting a woman, men often walk a very difficult line. Of course, (4)(context)matters. In a professional setting, talking about appearance is often inappropriate, but at a singles club, it may be important. She will be very pleased if a man thinks her clothes and (5)(accessories) are pretty, or her hair looks wonderful. However, things inbetween these two cases are unclear. Women have every right to be recognized and (6)(appreciated) for their intelligence and creativity. But at the same time, they want to be admired for their looks as well, for example, their perfect skin (7)(complexion) and elegant outfits.Unfortunately, most guys don't understand this. If we receive compliments from women, they're usually about our achievements, not our looks. Most of us don't expect a woman to tell us how (8)(handsome) or sexy we are, and some of us would find it hard to regard such a(n) (9)(comment) as sincere. I'm not saying it's very hard to be a guy these days. It is important for every man to understand how to treat women with both respect and (10) (admiration). But as far as the right balance of these two is concerned, we really have no frame of reference, especially when it comes to looks.Fill in the blanks with the expressions given below. Change the form where necessary. Each expression can be used only once.1. Every month, the Community Services Center offers several lectures onhealth and fitness (in hopes of) introducing people to healthierlifestyles.2. Do you know who (came up with) the idea of having cheesecake fordessert yesterday? It was delicious and made everyone happy.3. The pain medication left Claudia feeling rather dull and sleepy, and soonafter dinner she apologized for being such poor company and(excused herself) to bed.4. When I was young, I (was obsessed with) maps, and I sometimesspent the whole day charting land routes from one point to another.5. To make immigrants comfortable (reaching out to) police for help,more than 70 cities now bar police from asking them to prove their legal status.6. Mary was often accused of "having a strong personality" because she wasnot afraid to (voice an opinion on) subjects about which she wasknowledgeable.7. At the end of his term in office, the governor was criticized for failure to(live up to) his campaign promise.8. Results of a survey revealed that of the top 10 automobile makers (interms of) customer satisfaction, six were Japanese and two wereGerman.Write a contrast essay of no less than 200 words on the topic "How do women and men groom themselves?". You can follow the outline given below.Done with this activity. Time submitted: 2017-03-07 21:53 (Tuesday) Outline:How do women and men groom themselves?Women and men take care of their appearance in very different ways, which are mainly shown in three areas.• The variety of beauty tools and products they use• The amount of clothes they have• The amount of time they spend on grooming themselvesWomen and men behave differently in how they attend to their routinegrooming chores.My writing:When you get yourself ready to go to school or work in the morning, or attend a party in the evening, you may have to do various preparations. What youconsider as essential to prepare largely depends on whether you are a female or a male. Women and men take care of their appearance in different ways, which are mainly shown in three areas.One difference lies in the variety of beauty products that women and men use. Women have a great variety of tools and skincare products; for example, combs and clips for hair, brushes for powder foundation, and eyeliners for eyebrows, creams for face, to name just a few. Men, however, do not use so many things. They may comb their hair, but they seldom use cosmetics. Another difference involves the amount of clothes women and men have. Females usually have many more clothes than men do. You may well be familiar with movie scenes in which a woman tries on the outfits in her wardrobe one after another and still hesitates about which one to wear. Unlike females, males do not buy themselves piles of clothes as long as they still have something at home.The third difference is that women spend much more time grooming themselves than men do. It can easily take a woman half an hour or even several hours to get a perfect hair style or apply makeup to her face. In contrast, it may just take a man several minutes to tidy himself. All he needs to do is to comb his hair and put on whatever clothes he finds in the drawer.To conclude, women and men behave differently in how they attend to their routine grooming chores. Such distinctions help create the typical images of females and males in human society.Translate the following paragraph into Chinese.Done with this activity. Time submitted: 2017-03-07 21:53 (Tuesday) The originalWilliam Shakespeare is widely regarded as the greatest writer in the English language and the world's pre-eminent (杰出的) dramatist. His plays have been translated into a vast number of languages and are performed more often than those of any other playwright. Shakespeare's early works were mostly comedies and histories, which have the reputation of being among the finestmasterpieces produced in these genres (体裁) even today. Later on, Shakespeare wrote mainly tragedies, some of which, like Hamlet and King Lear, earned him fame in the entire Western literature. The most striking features of Shakespeare are his brilliant use of language and his universal themes. He contributed thousands of words to English, many of which have become embedded in the language. His themes are so universal that they transcend generations to stir the imaginations of readers and audiences worldwide. Shakespeare has influenced and inspired many writers over the centuries. His writings remain highly popular today, and they are constantly studied, performed, and reinterpreted in diverse cultures throughout the world. Shakespeare will continue to have an enormous impact on future playwrights, novelists, poets, actors, and scholars.My translation人们普遍认为，威廉•莎士比亚是最伟大的英语作家和世界杰出的戏剧家。
新探索研究生英语(提高级)unit4
新探索研究生英语(提高级)unit4Title: New Explorations in Research on Graduate English (Advanced Level) Unit 4In Unit 4 of the New Explorations in Research on Graduate English (Advanced Level), students delve deep into the topic of academic writing. This unit focuses on honing the skills necessary for producing high-quality research papers, essays, and other academic texts. It also covers important concepts such as thesis statements, organization, coherence, and citation.One of the key objectives of Unit 4 is to help students understand the structure of academic writing. This includes learning how to create a strong thesis statement that clearly outlines the main argument of the paper. Students also explore different organizational techniques that can help them present their ideas in a logical and coherent manner.Another important aspect of Unit 4 is citation and referencing. Students are taught the importance of giving credit to other scholars and researchers by properly citing their work. They learn how to use different citation styles, such as APA, MLA, and Chicago, and practice incorporating sources into their own writing effectively.Moreover, Unit 4 encourages students to engage critically with the literature on their chosen topic. They learn how to evaluate sources for credibility, relevance, and bias, and how to synthesize information from multiple sources to develop their own arguments.Overall, Unit 4 of the New Explorations in Research on Graduate English (Advanced Level) provides students with the tools and strategies needed to excel in academic writing. By mastering the skills covered in this unit, students will bewell-equipped to produce high-quality research papers and essays that contribute meaningfully to their field of study.。
人教_高一英语必修四_Unit4_单元主题素养阅读
Unit4 单元主题素养阅读时事阅读阅读提示：根据美国之音报道,谷歌公司给予创造了Apgar测试的医生极大|的荣誉。
这位医生是谁? Apgar测试的意义何在?This is What's Trending Today.The search engine Google is honoring the life of an American doctor who developed a system for measuring a newborn baby's health.Virginia Apgar is the subject of the Google home page's latest Doodle. Thursday would have been Apgar’s 109th birthday.As Google explains，Apgar，s presence can still be felt in delivery rooms across the globe.As a medical student，Apgar noted that a number of babies that had seemed healthy at birth were dying soon after leaving the hospital. This was because there was no commonly used method for measuring newborn health.In 1952，she created a life-saving test. This five-step test has doctors examine the appearance, pulse, grimace (怪相)，activity, and breath of newborns. The test is easy to remember. The first letter of each step spells Apgar ：A-P-G-A-R.Doctors score each part score of zero to two，with the highest total score being 10. They examine the newborns one minute after birth and then again five minutes after birth. The scores help doctors identify whether a baby has health issues requiring extra care.The APGAR test soon spread in America and around the world. It is still widely used today.Apgar9s life included many other successes. In 1949，she became the first woman to be named a full professor at the medical school she attended, Columbia University、College of Physicians and Surgeons, in New York City.Later，she led the birth defects department at the organization known today as the March of Dimes.Thursday’s Google Doodle appeared for internet users in the United States, as well as Japan，India, Israel, Chile, Argentina, Australia and several European nations.Apgar was born on June 7，1909. She died in 1974 at the age of 65.In 1995, she was admitted into the National Women’s Hall of Fame.And that’s What’s Trending Today.I’m Caty Weaver.1.Why is Virginia Apgar being honored by the search engine Google?A.Because she was admitted into the. National Women’s Hall of Fame.B.Because she was named a full professor at the medical school.C.Because she developed a system for measuring a newborn baby’s health.D.Because she examined the newborns one minute after birth.2.What happened to many newborn babys after they left the hospital?A.They were dying soon.B.They got APGAR test.C.They seemed healthy.D.They required extra care.答案1. C2. A经典阅读阅读提示：《杀死一只知更鸟》是由美国女作家哈珀·李所创作的长篇小说。
新版新视野大学英语读写教程第四册unit4答案
work at home rather than go to the office.
3. Some people sayபைடு நூலகம்that the pupils' achievements this term will be measured by a formal test rather
than their teacher's assessment.
4. They argued that their products should be developed on the basis of need rather than profit.
5. During weekends the businessmen may spend time establishing friendship and mutual trust rather
VIII.
1. auto-timer 2. auto-focus 3. autograph 4. auto-reverse
5. autobiography 6. automakers 7. autoloading 8. autocriticism
sentence structure
IX
1. Concentrate on indoor delights rather than outdoor fights and you'll be much better appreciated.
the two. Under the new welfare system, the law encourages welfare clients to work on their own for a
人教版高中英语选择性必修第四册unit1复习课件
2. They bought ten computers last term．
Ten computers were bought (by them) last term. 一般过去时：S+was/were +过去分词
五、何时使用被动语态呢？
一、行为主体不明确，不必说出或者无 法说出动作的执行者时。例如：
Football is played all over the world．
二、不易找到或根本就不可能找到动作 的执行者时。例如：
My bike was stolen．我的自行车被盗了。
三、汉语中含有“据说”、“据悉”、“有 人说”、“大家说”等时。例如：
Some country music was played for us.
31
七、 被动语态的几个问ቤተ መጻሕፍቲ ባይዱ： 3. 带复合宾语的动词的被动结构
例：His father called him Jack. He was called Jack by his father.
带复合宾语的动词变被动语态时, 一般将主动结 构中的宾语变为被动结构中的主语, 而将宾语补 足语保留不动(这时的宾语补足语为主语补足语)。
七、 被动语态的几个问题：
有些不及物动词主动形式可表被动意义
例：It can’t move. The door won’t shut.
7. 某些与 can’t, won’t 等连用的不及物动词， 如move, lock, shut, open等。
七、 被动语态的几个问题：
人教版选择性必修四Unit1ScienceFiction知识清单
[练透]—单句语法填空
12.We declare________garbage-sorting in new efforts to better protect the environment. (用适当的词填空)
【答案】for
【解析】
【详解】考查固定搭配。句意：为了更好地保护环境，我们支持进行垃圾分类。根据句意和空格前的动词declare可知，此处是考查declare和介词for的搭配declare for“表明赞成（拥护）”。故填for。
【解析】
【详解】考查名词。句意：一旦你预约了，你就应该遵守，而不是违背。结合句意及空前 made an可知，应填名词形式appointment，做宾语，短语make an appointment意为“预约；约会；预约时间；约定”，固定搭配。故填appointment。
9.I was appointed________(take) charge of arranging all the activities on that day. (所给词的适当形式填空)
6.explode vi.& vt.爆炸；爆破→________n.爆炸；爆破（声）→________adj.易爆炸的；猛增的
7.mud n.泥；泥浆→________adj.泥泞的
【答案】1. ①.appointment②.appointed
2.guilty3.weekly
4.declaratiຫໍສະໝຸດ n11．gripvt.&vi.紧握;抓紧
12．hazyadj.模糊的;朦胧的;困惑的
13．joltn．震动;摇晃;颠簸vt.&vi.(使)震动;摇晃
14．flipvt.&vi.(使)快速翻转;(用手指)轻抛
- 1、下载文档前请自行甄别文档内容的完整性，平台不提供额外的编辑、内容补充、找答案等附加服务。
- 2、"仅部分预览"的文档,不可在线预览部分如存在完整性等问题,可反馈申请退款(可完整预览的文档不适用该条件!)。
- 3、如文档侵犯您的权益，请联系客服反馈,我们会尽快为您处理(人工客服工作时间：9:00-18:30)。
For example, the latter is not present in the p = 3 case, i.e. the T6 /Zsequel, we describe all nilpotent algebras Np [41], corresponding to axion symmetries of the R–R and NS–NS scalars for all orientifold models. All Np ’s are nilpotent subalgebras of so(6, 6), are generically non–abelian and contain central charges. There are four of them in type IIB (p = 3, 5, 7, 9) with dimensions 15, 23, 23, 15 respectively, while there are only three of them in type IIA (p = 4, 6, 8) of dimensions 20, 24, 20, respectively. A common feature of these algebras is that they always contain fifteen R–R axionic symmetries, while the extra symmetries correspond to NS–NS B –field axions in the bi–fundamental of GL(9 − p, R) × GL(p − 3, R). A further R–R axion symmetry originates from the SU (1, 1), which acts as electric– magnetic duality on the gauge fields living on the brane world–volume. The corresponding axion field can be identified with the Cp−3 R–R field, as dictated by the coupling
∗
3
Spinoza Institute, Leuvenlaan 4 NL-3508, Utrecht, The Netherlands sergio.ferrara@cern.ch,
♭
e-mail:
⋆
carlo.angelantonj@cern.ch ,
M.Trigiante@phys.uu.nl
Abstract We consider classes of T6 –orientifolds, where the orientifold projection contains an inversion I9−p on 9 − p coordinates, transverse to a Dp–brane. In absence of fluxes, the massless sector of these models corresponds to diverse forms of N = 4 supergravity, with six bulk vector multiplets coupled to N = 4 Yang–Mills theory on the branes. They all differ in the choice of the duality symmetry corresponding to different embeddings of SU (1, 1) × SO(6, 6+ n) in Sp(24+ 2n, R), the latter being the full group of duality rotations. Hence, these Lagrangians are not related by local field redefinitions. When fluxes are turned on one can construct new gaugings of N = 4 supergravity, where the twelve bulk vectors gauge some nilpotent algebra which, in turn, depends on the choice of fluxes.
Carlo Angelantonj1,† , Sergio Ferrara1,2,‡ and Mario Trigiante3,♭
1
CERN, Theory Division, CH 1211 Geneva 23, Switzerland
2
INFN, Laboratori Nazionali di Frascati, Italy
1.
Introduction
New string or M–theory models are obtained turning on n–form fluxes, which allow, in general, the lifting of vacua, supersymmetry breaking and moduli stabilisation [1]–[24]. Examples of such new solutions are IIB and IIA orientifolds [25, 26, 27, 28, 29], where the orientifold projection (in absence of fluxes) preserves N = 4 or N = 2 supersymmetries. Recently, the T6 /Z2 orientifold with N = 4 supersymmetry [8, 9] and K3 × T2 /Z2 orientifold [24] with N = 2 supersymmetry have been the subject of an extensive study. In these cases, turning on NS–NS and R–R three–form fluxes allows to obtain new string vacua with vanishing vacuum energy, reduced supersymmetry and moduli stabilisation [7, 8, 9, 21, 24]. These features can all be understood in terms of an effective gauged supergravity, where certain axion symmetries are gauged [31, 30, 32]. These are generalised no–scale models [33, 34]. In the present investigation, we consider more general four–dimensional orientifolds with fluxes (both in type IIB and IIA) where the orientifold projection involves an inversion I9−p on 9 − p coordinates, transverse to the Dp–brane world–volume, thus generalising the T6 /Z2 orientifold (with p = 3) constructed by Frey–Polchinski [8] and Kachru–Shulz– Trivedi [9] (see also [10] for a derivation of the complete low–energy supergravity from T–dialysed Type I theory in ten dimensions). Interestingly, their low–energy descriptions are all given in terms of N = 4 supergravity with six vector supermultiplets from the closed–string sector, coupled to an N = 4 Yang–Mills theory living on the Dp–brane world–volume. However, despite the uniqueness of N = 4 supersymmetry, the low–energy actions crucially differ in the choice of the manifest “duality symmetries” of the Lagrangian, since different sets of fields survive the orientifold projection, and therefore different symmetries are manifestly preserved. Leaving the brane degrees of freedom aside, these duality symmetries are specified by their action on the (twelve) bulk vectors. Actually, N = 4 supergravity demands that such symmetries be contained in SU (1, 1) × SO (6, 6) [35, 36] and act on the vector field strengths and their duals as symplectic Sp(24, R) transformations [37]. On the other hand, the symmetries of the Lagrangian correspond to block–lower– triangular symplectic matrices, whose block–diagonal components have a definite action on the vector potentials [38, 39, 40]. For instance, in the orientifold models containing an I9−p inversion, the block–diagonal symmetries always include GL(9 − p, R) × GL(p − 3, R), as maximal symmetry of the GL(6, R) associated to the moduli space of the six–torus metrics. The lower–triangular block contains the axion symmetries of the R–R scalars and of the NS–NS ones originating from the B –field, whenever present1 .