a r X i v :a s t r o -p h /0511610v 1 21 N o v 2005Accepted for publication in the Astrophysical Journal
The bulk Lorentz factor crisis of TeV blazars :
evidence for an inhomogeneous pileup energy distribution ?
Gilles Henri Laboratoire d’Astrophysique de Grenoble,Universit′e Joseph-Fourier,BP 53,F-38041Grenoble,France and Ludovic Saug′e Institut de Physique Nucl′e aire de Lyon,UCBL/IN2P3-CNRS ,4,rue Enrico Fermi,F-69622,Villeurbanne cedex,France Gilles.Henri@obs.ujf-grenoble.fr,l.sauge@ipnl.in2p3.fr ABSTRACT There is growing evidence that the estimations of the beaming Doppler factor in TeV BL Lac object based on the Self Synchrotron Compton (SSC)models are in strong disagreement with those deduced from the uni?cation models between blazars and radio galaxies.When corrected from extragalactic absorption by the di?use infrared background (DIrB),the SSC one-zone models require very high Lorentz factor (around 50)to avoid strong γ?γabsorption.However,the statis-tics on beamed vs.unbeamed objects,as well as the luminosity contrast,favors
much lower Lorentz factor of the order of 3.In this paper,we show that for the special case of Markarian 501,the need for very high Lorentz factor is unavoid-able for all one-zone models where all photons are assumed to be produced at the same location at the same time.Models assuming a double structure with two di?erent beaming patterns can partially solve the problem of luminosity contrast,but we point out that they are inconsistent with the statistics on the number of detected TeV sources.The only way to solve the issue is to consider inhomoge-neous models,where low energy and high energy photons are not produced at the same place,allowing for much smaller Lorentz factors.It implies that the jet is strati?ed,but also that the particle energy distribution is close to a monoen-ergetic one,and that pair production is likely to be signi?cant.The implications on relativistic jet physics and particle acceleration mechanism are discussed.
Subject headings:radiation mechanisms:non-thermal—gamma rays:theory—
galaxies:active—galaxies:BL Lacertae objects:general—galaxies:jets
1.Introduction
It is now admitted that the blazar phenomenon is due to relativistic Doppler beaming
of the non-thermal jet emission taking place in radio-loud Active Galactic Nuclei(AGN)
where the jet axis is closely aligned with the observer’s line of sight.They exhibit an
important level of optical polarization,a?at radio spectrum,a strong variability in all
frequency bands and a very broad spectral energy distribution(SED)ranging from the radio
to the extreme gamma ray band.The SED consists typically in two broad components.
In the so-called Synchrotron-Self-Compton process(SSC)model,the lowest energy hump is
attributed to the synchrotron emission from relativistic electrons and/or positrons,and the
highest one is attributed to the Inverse Compton(IC)process of the same charged particles
onto the synchrotron photons and/or external photons.The blazar class of objects includes
both the Flat Spectrum Radio Quasars(FSRQ)and the BL Lac sources(or Lacertids),
depending respectively on the existence or the lack of detectable emission lines in their
spectra.Following Chiaberge et al.(2000),one can de?ne two classes of BL Lac objects
(which are most probably two extreme cases in a continuous distribution):the LBL or
”red”BL Lac,for which the synchrotron component peaks in far IR to optical,and the IC
component peaks in the MeV-GeV range,and the HBL or”blue”BL Lac,for which the
synchrotron component peaks in the UV-X range,and the IC component peaks above10
GeV.The most extreme objects up to now are those whose non thermal emission extends
up to the TeV range,the so-called TeV blazars.The two main prototypes are Mrk421
(Punch et al.1992)and Mrk501(Quinn et al.1996),two radio-loud AGN relatively close
to us and roughly at the same distance,z s≈0.031and z s≈0.034respectively.Five other TeV detections have been repeatedly detected(1ES1959+650,PKS2155-304(Aharonian et
al.2005a),1ES1426+428and PKS2005-489(Aharonian et al.2005b),and1ES2344+514
(Aharonian et al.2004)).All of them are Lacertids,although it is not clear up to now
whether only BL Lac objects do emit TeV radiation or if this is due to a selection e?ect.As
a matter of fact,BL Lac objects appear to be much more numerous than quasars and the
closest blazars all belong to this class.A high sensitivity threshold would strongly bias the
detection toward the closest sources.Furthermore it is well-known that TeV photons are
absorbed by the Di?use Infra Red Background(DIrB)to create electron-positron pairs,and
it is not obvious whether even the closest quasar,3C273(z s≈0.158)could be detected in the TeV range.
One-zone SSC models assume that highly relativistic particles are injected in a spherical zone,where they cool by emitting synchrotron radiation and by Inverse Compton process. The models require specifying the source radius,the magnetic?eld,as well as the density and the energy distribution of the emitting relativistic particles.The latter is most often assumed to be a power law or a broken power law(e.g.Marscher1983;Tavecchio et al. 1998).It turns out however that the computation of emitted radiation is not compatible with the hypothesis of a static source,because in most cases the photon density would be so high that all TeV photons should be absorbed to form electron-positron pairs.Furthermore the time variability is so short(down to15minutes in some cases,Gaidos et al.(1996))that it is incompatible with a spherical static source through the causality argument.This leads to assume that the source is moving with a relativistic bulk velocity v=βc.The e?ect of relativistic bulk motion is entirely described by the Doppler beaming factorδ=1/Γ(1?βμ), whereΓ=(1?β2)?1/2is the usual Lorentz factor andμ=cosθis the cosine angle of the jet according to the observer’s line of sight.The Doppler e?ect shifts all frequencies by a factor δand all speci?c intensities by a factorδ3.So the actual photon density in the jet frame is much lower than what would be deduced for a static source.The relativistic motion has been invoked for a long time(Rees1966)to solve a similar issue for radio emission of quasars. Namely the brightness temperature is so high that,for a static sources,the relativistic lep-tons emitting synchrotron radiation should have cooled immediately through the so-called ”Inverse Compton catastrophe”(Rees&Simon1968).Again the relativistic motion can?x this issue,because the actual photon density in the jet frame is much lower when taking into account the Doppler ampli?cation.This beautiful theoretical explanation has been later con?rmed by the discovery of superluminal motion,which requires Lorentz factors at least as great as the observed apparent reduced velocityβapp=v app/c(for a review,see Zensus 1997).
Forμ β,corresponding toθ 1/Γ,one has1 δ 2Γ,whereasδ～1/Γoutside this interval.It means that for a few beamed Doppler sample of boosted sources,one expects a lot of unbeamed and not ampli?ed counterparts.It is natural to think that the unbeamed counterparts of bright quasars are the weaker radio galaxies,whose jet is thought to make a larger angle with the line of sight.Particularly it has been proposed that the unbeamed counterparts of BL Lac object could be a sub class of radio galaxies,the so-called Fanaro?-Riley I(FRI)radio galaxies(Urry&Padovani1995).These are characterized by a rather faint,weakly beamed,and core-brightened radio jet.Statistical studies of radio and X-ray AGN samples have con?rmed the possibility of such an association.The inferred beaming factors seem to imply a rather modest value of the bulk Lorentz factor,of about3.However, the modeling of SSC radiation by one zone models requires much higher values:following the authors,they range from10to50(Tavecchio et al.1998;Konopelko et al.2003;Saug′e &Henri2004).The highest value seems to be needed when one takes properly into account
the extragalactic absorption.The problem is further complicated by the absence of clear superluminal motion in TeV blazars,together with a rather modest brightness temperature, which implies also a low Lorentz/Doppler factor(Edwards&Piner2002;Piner&Edwards 2004).All these contradictory facts lead to what we call here the”Bulk Lorentz factor crisis of TeV blazars”.
The aim of this paper is?rst to ascertain this crisis.We will?rst show that all one-zone SSC models imply high Lorentz factors,only with the argument ofγ?γabsorption and discarding any variability argument.Then we will recall the arguments for low Lorentz fac-tor,based on general geometric properties of the Doppler boosting.We will show that the explanations based on two di?erent structures,with a possible deceleration of a fast spine responsible for TeV emission,are not satisfactory concerning the statistics of TeV blazars. We argue that the best solution is to admit the low Lorentz factor constraint,abandoning the one-zone assumption.We will show that this conclusion has important consequences regarding the jet physics and the particle acceleration mechanism.
2.The case for high Lorentz factor
In the following,we will develop the need for high Lorentz factors for one-zone models, with the fewest theoretical assumptions and relying only on observational data.We will only assume that the SSC process is at work,with the usual assumptions of one-zone models:the relativistic particles are assumed to be injected in a spherical homogeneous”blob”of radius R,moving at a relativistic velocity characterized by the Lorentz factorΓand a corresponding Doppler factorδ.The blob is?lled with a tangled magnetic?eld of constant strengh B.We will refer to all quantities expressed in source rest frame by a star and quantities in observer’s frame are not labeled.All energies are expressed in reduced unit of m e c2.Throughout this paper,we express the Hubble parameter by H0=100h km s?1Mpc?1and assuming h to be equal to h=0.65.
2.1.The synchrotron and IC di?erential Luminosity
Inspection of the TeV blazars spectra shows that the IC spectra reaches their maximum luminosity at some peak energyεc,which is of the order of106for TeV photons.This energy corresponds to an energyε?c=εcδ?1in the blob frame.We will consider only the particles
emitting this typical energy via the IC process,which have a typical individual Lorentz factor (in the blob frame)γc,which must be greater thanε?c.
We then de?ne another typical energyεs,that is emitted by synchrotron process by the same particles.It can be expressed in the blob frame asε?s=(B/B0)γ2c where B0=3B c/2and B c=2πm2e c3/eh≈4.41×1013G is the usual“QED critical magnetic?eld strength”.One has thenεs=δ(B/B0)γ2c.Synchrotron spectra of TeV blazars are typically peaking in the 1-100keV range so thatεs～10?2?10?1.
Synchrotron photons are up-scattered at high-energy via Inverse Compton process.It has been stressed by various authors that,giving the observed energies of IC and synchrotron photons,the collisions between the most energetic particles and the peak synchrotron photons take place in the Klein-Nishina regime,that isε?sγc 1.In this condition,the particle (electron or positron)gives all of his energy in a single interaction.It follows thatγc～ε?c. This gives an estimate of the magnetic?eld strength,
B=B0ε?s
ε2c
(1)
which is only valid in the Klein-Nishina scattering regime.
The di?erential synchrotron luminosity Lε,s per unit reduced energy emitted by a pop-ulation of particles of energyγat the energyεs with di?erential energy number of particles
d N/dγreads
Lε,s(εs)=d L s
dε?
(ε?s)=δ3
d L?s
dγ
dγ
3
cσTh W B
ε3c
dγ
(3)
where W B=B2/8πis the usual magnetic energy https://www.doczj.com/doc/cf17744113.html,bining with equation(1),we
can write:
Lε,s(εs)=δ31
εc
d N
Photons of this energy will also be the main contributors for absorbing photons of energyεc to create electron/positron pairs.If we neglect the Klein-Nishina contribution aboveεt,the total power lost per particle of energyγwrites d L?c/d N=(4/3)cσThγ2W e??
ph
,where
W e??
ph =
L e??
s
4πR2c ε?tε?min dε?d L s
4πR2c
δ?2
3πR2
εc Lε,s(εt)
d N
2πm2e c7/2εc
βεs Lε,s(εt)Lε,s(εs)
d z
τγγ(ε?)=αγγσThε?t n(ε?t),
where?γγ(ε?)is the free mean path of the photon and n(ε?)the di?erential photon density per unit of reduced photon energyε?.In the framework of one-zone model,the typical interaction scale is of the order of the size of source R.It follows that the typicalγ?γoptical depth writes,
τγγ(ε?)≈
R
The functionαγγ(Svensson1987;Coppi&Blandford1990)depends on the indexβof the power-law of the spectral soft photon density expressed inνFν∝νβform.A commonly used value ofαγγ(β)is0.2or0.25.More precisely we have(Svensson1987)
αγγ(β)=41?β6×Γ2(2?β)
(4?β)(3?β)
.(9)
The di?erential energy density number of particle is given as a function of the di?erential luminosity by
n(ε?t)=
L?ε,s(ε?t)
4πm e c3R =δ?3αγγ(β)
σTh Lε,s(εt)
6eh
(12)
×√
εc Lε,s(εt)Lε,IC(εc)β.Values of?αγγandαγγ
for someβare tabulated in table2.
2.3.Constraints on the local synchrotron spectral shape
Equation(2)shows that if we are able to measure the position in frequency and?ux of both the synchrotron and the IC peak,then we can evaluate the optical depth toγ?γabsorption at the IC peak as a function of the assumed Doppler factor value.This optical depth is controlled by the synchrotron luminosity at the frequencyεt=δ2/εc.We can use this relation either by assuming some Doppler factor and evaluate the optical depth, or constrain the value ofδby limiting the value ofτγγ.We can de?ne r max,the Compton dominance parameter,as the ratio of IC luminosity’s peak to the synchrotron one,
r max=[νc F c(νc)]
max
εs Lε,s(εs)
.(13)
We can rewrite equation(12)to express the luminosity atεt=δ2/εc as a function of the optical depth and the r max parameter.We?nally obtain,
εt Lε,s(εt)=δ4
?αγγ(β)
6eh
εmax
s
2
.(14)
Equations(5)and(14)can be considered as a system of two parametric equations of the curve givingεt Lε,s(εt)as a function ofεt.Eliminatingδbetween the two previsously cited equation,one gets the following expression:
εt Lε,s(εt)=ε2tε2c
?αγγ(β)
6eh
εmax
s
2
.(15)
For nearby sources,the luminosity distance writes d?(z)≈cz/H0and previous expression can expressed in term on?ux F instead luminosity L using the well known relation F=L/4πd2?, νs d F s zτγγ(εmax c)νmax s 2r?1max(16) For an observed SED and a given value of the opacity parameterτγγ,the only remaining unknown quantity in the previous equation is the beaming Doppler factorδ.Each value ofδgives a point in the log10ν?log10(νFν)plane lying on straight line of slope2,the level of the curve depending only on the value ofτγγ.Intersection of the synchrotron spectrum with the straight line directly constrains the minimum valueδmin(τγγ)of the beaming Doppler factor required to avoid theγ?γabsorption with an opacity value ofτγγof the Inverse Compton bump(at the peak frequency).
2.4.Application to Markarian501
We apply this calculation to the case of the Mrk501object during the period of the 1997April16where the Beppo-SAX satellite(Pian et al.1998)and the CAT imaging At-mosphericˇCerenkov Telescope(Djannati-Ata¨?et al.1999;Barrau et al.1998)have recorded simultaneous data(see?gure2).All observational parameters we need in the equation(16) are reported Table1.We consider the two cases where we take into account,or not,the attenuation of the high energy component by cosmic di?use infrared background(DIrB). This e?ect consists in the interaction of emitted gamma rays during their travel through the Universe with the photon?eld of the di?use infrared background(DIrB)to create pairs (Gould&Schr′e der1967a,b;Stecker,de Jager,&Salamon1992;Vassiliev2000).The tail of the high energy spectra is then de-reddened using the method described in Saug′e&Henri (2004).This situation changes the position of Inverse Compton peak and the Compton dominance parameter r max.In this case,forτγγ=1,we obtain both in the reddened and the de-reddened caseδmin(1)≈50(see?gure3).
Given equation16,the position of the line constrainingδdepends on the value of (?max
c
)4/Lε,IC.It turns out that,also the IR un-folding of the spectrum changes both quan-tities,the previous ratio depends only slightly on the level of assumed absorption.The
value ofδmin(1)are thus quite similar in the two cases because when we correct the Inverse Compton bump,position of the maximum moves both in luminosity and in frequency.This e?ect could be clearly seen on?gure3,where the di?erence between the two panels is hardly perceptible.
Note that in fact the level of the curve depends implicitly also on the value of modi?ed power-law index of the spectrumβ(see eq.[16]).In our case,we choose a valueβ=0.5 directly measured on the SED.
2.5.Constraint from the variability timescale
Another constraint can be derived from the observation of short variability timescale. The classical argument is that a spherical static source cannot be variable on a timescale smaller than R/δc.So one gets an upper bound of radius of the source R R var,min=δct var. Combining previous inequality to the equation(8)and expressing all the quantities in their ?ducial units,we?nally get a constraint similar to the one obtained in the previous section for the local synchrotron shape(see eq.[16]):
νs d F s zνmax s
For a component moving along the jet axis at a reduced speedβ=v/c and making an angle θfrom the line of sight,the apparent transverse velocity measured by the observer is:
βsinθ
βapp=
2/2andθis such that sin2θ>(Γ2?1)?1,the motion will appear to be superluminal i.e.βapp>1.Expressed in degrees the latter condition writesθ>θcrit= 0.28(Γ/10)?2deg.
As a matter of fact,VLBI/VLBA campaigns have not clearly succeeded in?nding su-perluminal motion at the parsec scale for any TeV blazars(Edwards&Piner2002;Piner& Edwards2004).Observed radio components seem to be stationary or subluminal,requiring low or moderate values of the Lorentz factor(Γ≈2?4).
The absence of superluminal motion could be explained by a very close alignment of the jet with the line of sight.Indeed,following the previous expressions,ifθ 1/2Γ2the apparent velocity is always smaller than c,and object appears to be subluminal despite the large value ofΓ.But it this case,a simple statistical argument based on the density number of unbeamed counterparts rule out this possibility as we will see in the next section.
Moreover,derived value of the brightness temperature of the VLBI core is in the order of1010?11K and lie well below the usual Inverse Compton limit of≈1011?12K necessary to avoid the”Inverse Compton catastrophe”,i.e.situation where ultra-relativistic particles su?er from dramatically Compton cooling in a very short time.Piner&Edwards(2004)have concluded that the jet should be only mildly relativistic at parsec scale.They propose that the TeV emitting inner jet is strongly decelerated before reaching the parsec scale.However we will see in the following that the existence of the highly relativistic motion is challenged by other observational facts concerning the statistics of beamed vs.unbeamed sources.
3.2.Number of beamed sources
in the BL Lac/FR-I uni?cation paradigm
As we said in the introduction,the blazar phenomenon arises from a close alignment of jet axis with the observer’s line of sight.Following this scheme,one expects the existence of sources sharing the same physical properties(i.e.intrinsically the same objects),but viewed at larger angle.It has been proposed that Fanaro?-Riley radio galaxies can be the unbeamed parent population of blazars and particularly,FR-I galaxies can be the counterparts of Lacertids(Urry&Padovani1995).
The uni?cation hypothesis can be tested on samples of objects both by their luminosity ratio and by their spatial density.Doppler beaming e?ect enhances the intrinsic bolometric luminosity by a factorδ4.The Doppler factor itself varies fromδmax=2Γfor a jet pointing exactly toward the observer,toδmin=1/Γfor jets lying close to the sky plane.Although the exact de?nition of what is a beamed object can be somewhat subtle,one can estimate an order of magnitude of the number of such objects.It is easy to see that the solid angle for which the Doppler factor is larger than some given valueδ0(where of courseΓ?1<δ0<2Γ
is
?=2π(1?μ0)?2π
δ0?
1
Γ 12Γ ,(20)
if we assume always two symmetrical jets.
So any”beaming criterion”imposing a Doppler factor larger than some sizable fraction of Γwill give a fraction of beamed sources of the order ofΓ?2.For one beamed source,one expects thus aroundΓ2unbeamed sources.It turns out that careful statistical studies do indeed con?rm the association of BL Lac objects with FR-I galaxies,but they converge toward a much lower Lorentz factor than what is expected from the gamma-ray emission. For X-ray selected BL Lacs,which comprise all known TeV blazars,the inferred density ratio is1:7,corresponding to a bulk Lorentz factor around3.5(Urry&Padovani1995).
In the same way,we can examine the hypothesis that the lack of detection of super-luminal motion would be due to a close alignment of the jet with the line of sight.As we note in the previous section,a beamed source withθ 1/2Γ2can not appear superluminal. The cone substained by this angle corresponds to the solid angle?≈π/4Γ4.The ratio f′between the density of unbeamed sources and subluminal beamed sources one is thus given by
f′=
n FR?I
in the BL Lac/FR-I uni?cation paradigm
Another constraint can be derived from the luminosity ratio between the Lacertids sources and the FR-I ones.Supposing the same assumption as above (see previous section
3.2),ie Lacertids and FR-I are on average the same intrinsic objects but viewed at di?erent angles,the bolometric luminosity contrast between the two parents population (Lacertids and FR-I radio galaxies)is given by,
?=L Lac δFRI
4.(22)In the case of Lacertids,relativistic beaming requires 0 θ 1/Γor equivalently 2Γ δLac Γ.On the other hand,we suppose that o?-axis counterparts verify δ≈2/Γ(corre-sponding to an average angle value of θ≈60deg for Γ>1).Then,equation (22)rewrites
Γ8 ? Γ8
First detection was reported by the HEGRA collaboration with an integral?ux above250 GeV at about3.3%of the?ux of the Crab Nebula(with a signi?cance of4.7σ)during an high state(Aharonian et al.2003;Beilicke et al.2004).Such TeV events are con?rmed by recent measurements of High Energy Stereoscopic System(HESS)(Beilicke et al.2005).The powerful radio jet of M87has been well studied in various wavelengthes from radio to X-rays, showing that the jet axis makes an angle between30and40deg with the line of sight.This angle is clearly large enough to ensure that the emission is unbeamed.Previous works based on the study of the proper motion of the VLBI knots(Biretta et al.1995)or on the detailed analysis of HST and VLA observations(Lobanov et al.2003)converge toward value forΓof 3–5at the kiloparsec scale.The jet di?erential?ux of a source expressed in the observer’s frame can be written as function of the intrinsic di?erential luminosity as
Fν(ν;θ,z)≈(1+z)δ3L?ν(ν?)
νthr dν[F bν(ν)/hν]= z b1+z u α?2 δu
δb 2+α,(25)
where the index u(resp.b)refers to the observed unbeamed(resp.beamed)quantities,and where we suppose that the high energy spectrum can be expressed as a simple power-law with a photon indexα.
For beamed sources,the Doppler factor can be written asδb≈2Γwhile for the unbeamed case one hasδu=1/Γ(1?βcosθ)<Γwithβ≈1?1/2Γ2.Finally we can express the bulk Lorentz factor as a function ofθand the observational parameters only
Γ(θ)= [k(z b,z u;α)R?1]1/(2+α)?cosθ
θ k(z b,z u;α)
In1997April?aring period,the TeV blazar Mrk501(z s≈0.034)became roughly8 times as bright as the Crab Nebula as reported by the French collaboration CAT(Djannati-Ata¨?et al.1999).Assuming M87is an unbeamed counterpart of Mrk501with an angle 30deg θM87 40deg we obtain4 Γ 5.3.Again we?nd that the luminosity ratio is compatible with modest values of the Lorentz factor.Due to the increasing sensitivity of the present and the next generation of the Imaging AtmosphericˇCerenkov Telescope Arrays,the detections of more and more TeV radio galaxies should help us to constrain the dynamics of the emitting plasma at the subparsec scale in a more reliable statistical way.
3.5.Summary
All the above considerations show that observational data are compatible with the beaming model only if the bulk Lorentz factor for the X-ray and TeV emitting part of the object is relatively low,between3and5.This value reproduces correctly the luminosity ratio and the statistical number of sources(which are a priori independant factors).Conversely, a value ofΓ=12.5which is the minimum typical value derived from the one-zone modeling approach,would lead to a luminosity contrast of?≈107.6–109.This latter estimation is clearly not compatible with the previous observations,ascertaining the”Bulk Lorentz factor crisis of TeV blazars”.In the following,we will examine some suggestions made by various authors to solve the crisis.
4.How to solve the crisis
4.1.Two pattern model
Chiaberge et al.(2000)and Trussoni et al.(2003)argue that a jet velocity structure can solve the problem of the BL Lac/FR-I uni?cation scheme.They consider a(med-)relativistic external layer and a fast internal spine which dominates the emission in the case of a favorable alignment along the observer’s line of sight,i.e.in the blazar case.Although similar in appearance to the two-?ow model of Pelletier(1985)(see below for details),it di?ers by the fact that both?ows are relativistic,one with a”low”Lorentz factor(around 3)and one with a high Lorentz factor(at least10).In the following,we consider the same approach considering a two-components modeling of the velocity structure,where a fast inner structure is supposed to be surrounded by a slow one.Each of these components is respectively characterized by a bulk Lorentz factorΓf andΓs.As we saw,the radiative emission of the moving source with a bulk Lorentz factorΓis beamed in a cone sustained
by a solid angleδ?=π/Γ2along the motion.Therefore the emitted radiation appears to
be Doppler boosted when the jet lies intoδ?around the observer’s line of sight.In this
case,the luminosity contrast between the two parents population(Lacertids and FR-I radio
galaxies)writes,
Γ8s ? (ΓsΓf)4,(28) where right and left bound correspond to the case where fast velocity component respectively
dominates or not the emission.Uni?cation models are sensitive to the slow component only,
so(Γs=3?5)(Hardcastle et al.2003;Trussoni et al.2003;Chiaberge et al.2000;Urry&
Padovani1991).Therefore,assumingΓs≈4we obtain104.81 ? 108ifΓf=25and 104.81 ? 106.4ifΓf=10.
The results give a possible solution to the luminosity ratio problem,being more compatible
with observations.But in the next section we will examine the consequences of such a
velocity structure on the detection probability of TeV emitters among BL Lac objects.
4.1.1.Statistics of detected sources
Suppose a populationΣof sources randomly oriented per unit volume n0.Then the
density number of sources oriented with an angleθ=cos?1μaccording to the observer’s line
of sight is d n/dμ=n0/2.We de?ne BL Lac sources as those seen into theδ?s=π/Γ2s cone
and therefore the TeV emitters as the part of Lacertids lying into theδ?f=π/Γ2f.Therefore
the probability of detecting a BL Lac object inΣwrites
P Lac=P(μ μ0)=1dμ=1
Γf 2.(30) The probability of detecting n TeV emitters among a population of N Lacertids is given by the usual binomial probability law,
P(n/N)=N!
which writes,
P(N n0 n)=k=N
k=n P(k/N).(32)
4.1.2.Applications
For a given value of(n,N),requiring that P(N n0 n)is larger than an a pri-ori probability P0constrains the space parameters(Γs,Γf).The latter inequality leads to eliminate parameter’s region lying above a straight line which corresponds equivalently to a constant value of P0or of the ratioΓs/Γf(see eq.[32],[31]and[30]).Further restric-tion come from theγ?rays transparency argument and FR-I/Lacertids uni?cation models as developed above.
1.Firstly,theγ?rays transparency argument developed in the?rst part of this work
directly constrains the value of the fast component as it requires a minimum value of the Doppler factorδmin,and thereforeΓf δmin/2.We have shown thatδmin≈50 exclude all part of the(Γs,Γf)lying aboveΓf=25.
2.Secondly,basic statistics argument based on the number FR-I radio galaxies regarding
the Lacertid one and the comparison of luminosity distribution of the previous popu-lations constrain the value of the slow component to reasonable values less thanΓs≈7 (Urry&Padovani1995;Chiaberge et al.2000).
We test this result on the catalog of BL Lac objects from Padovani&Giommi(1995).At z s 0.13they report29Lacertids with known redshift.Setting(n=7,N=29),P0=1% and recalling thatΓs,max=7andΓf,min=25,the intersection of all listed previous constraints reduces to null region(see?gure5).Even with the hypothesis of a structured?ow,a large value of the Lorentz factor recquired by one-zone homogeneous models is clearly untenable (excluded with a con?dence level of99%).
We demonstrate that even if the two-components velocity structure can give a satis-factory answer to the luminosity problem of the Lacertids even with large value of Doppler factor required by high energy emission models,it fails to explain the detection statistics of the TeV emitters among the BL Lac object population supposed to be o?-axis FR-I sources.
5.Discussion
5.1.Inhomogeneous models
Altogether,the previous considerations lead to a serious paradox,where a high Lorentz
factor larger than20seems mandatory to avoid strongγ?γabsorption,whereas all other
facts tend to favour modest values around3.The only way to solve the discrepancy seems
to give up the implicit assumption of all one zone model,i.e.the fact that all photons are
produced co-spatially and simultaneously in some characteristic region of size R.Alterna-
tive to one-zone models have already been discussed in the literature.For instance,in the
”blob-in-jet”model(Katarzy′n ski et al.2001,2003),low energy photons are produced in a
continuous jet and only the high energy ones are produced in a spherical blob.This allow to
?t the overall spectrum with a smaller Doppler factor of around15.Another possibility is to
take explicitly the variability and use a time-dependant model to reproduce the data.Again,
the constraints arising fromγ?γopacity can be somewhat released because soft photons
are emitted at a later stage than high energy ones.As has been remarked by Ghisellini et
al.(1985),time-dependant model will produce e?ects comparable to inhomogeneous ones.If
the evolving source is moving at relativistic velocity,and that many?ares are contributing
to the emission,the overall system will be in fact an strati?ed jet composed with many
”one-zone”regions in a di?erent evolutionary stage.However,none of these models do use
bulk Lorentz factors as low as3.
We are led thus to consider models where photons are distributed along a jet in a
continuous structure,instead of?lling a spherical source.In this case,the luminosity is
proportional to the photon density times the lateral surface of the jet,which is2πR j h j=
2πAR2j,where R j and h j are the typical jet radius and length at the emission region,and
A=h j/R j is an aspect ratio of the source.For a self similar jet for which all quantities
(radius,magnetic?eld,particle density etc...)are described by power law as a function of
the distance z,one expects h j～z j,where z j is the distance of the emitting region from the center.It follows that A～z j/R j～θ?1j,whereθj is the typical opening angle of the jet.One can see that for a given synchrotron luminosity and photon density(implying the same IC
luminosity),one must conserve the quantity AR2j,so the typical radius of the jet,and hence
theγ?γoptical depth will be reduced by a factor A1/2with respect to a spherical source.
This simple geometrical modi?cation helps thus to increase luminosity without increasing
optical depth.Furthermore,the particle distribution needs not to be the same all along the
jet.Rather one expects a gradual cooling of the particles,the overall spectrum being the
envelope of all slices of the jet.The local photon spectrum can thus be di?erent from the
observed one,and particularly the local soft photon density can be much lower,helping again
to reduce theγ?γoptical depth.As we shall see,all these factors can o?er a clue to the Bulk Lorentz factor crisis,but imply strong constraints on the physical picture of relativistic jets.
5.2.Theoretical implications
5.2.1.Local photon density
Considering the above constraints,we will take the opposite attitude,considering that the value of the bulk Lorentz factor is constrained by the uni?cation models and the detec-tion of unbeamed sources to be around3.The typical high energy emission zone as de?ned above is equivalent to the superposition of A spherical sources with individual luminosities Lν/A～θj Lν.Therefore,all previous equations in section2are still valid provided we re-place the observed luminosity Lνbyθj Lν.Using equation(12),we conclude that all opacity
τγγ,which is of constraints remain unchanged if we replace the optical depthτγγbyθ?1/2
j
course in accordance with the estimate made in the previous paragraph.So we can use the ?gure3with slightly di?erent values ofτγγ.The typical angleθj must be of the order of 10?2?10?1,so the optical depth will be reduced by a factor between3and10.In the following,we will still use the same lineθ?1/2
τγγ≈1to constrain the optical depth,meaning
j
thatτγγ 0.1to0.3.
5.2.2.Local photon spectrum
We can thus put an upper limit on the soft photon luminosity corresponding to this value and a Doppler factor of3,which constrains the soft photon luminosity at an energy εt=δ2/εc～10eV.As the spectrum is by de?nition approximately the same in all the char-acteristic emission region,we can thus estimate the local photon spectrum by interpolating between the peak synchrotron luminosity and the above upper limit.Inspection of?gure 3shows that the spectral index between10eV and100keV is very close to1/3,which is characteristic of a quasi monoenergetic distribution;an example of such distribution is pro-vided by the quasi-maxwellian or”pileup”distribution(Henri&Pelletier1991;Schlickeiser 1985;Saug′e&Henri2004),which is a natural outcome of some acceleration processes like second order Fermi acceleration or magnetic reconnexion.This distribution is not the usual power law often claimed to exist in AGN,and which is naturally produced in MHD shocks. Rather than localized shocks,the assumption of low Lorentz factor leads to a picture of a
continuous jet?lled by relativistic particles,continuously reheated by a di?use acceleration mechanism.
5.2.3.Pair production
The local synchrotron spectrum can not be harder than the monoenergetic one;so?gure 3proves that this implies a lower limit to the quantityθ?1/2
τγγ 1.Thus the limit onγ?γ
j
optical depth can not be very low,unless we have an extremely well collimated jet that is not supported by the general FR-I morphology.Modest collimation factors imply that τγγ 0.1.This supports the formation of an electron-positron pair plasma in the acceleration site.If the acceleration is not localized,which is suggested by the picture of a continuous jet ?lled by a pile-up distribution,the pairs created byγ?γinteraction can not avoid being reaccelerated and will trigger a pair cascade(Henri&Pelletier1991).These constraints are thus suggestive of a inner continuous pair dominated,jet-like emission zone,maintained at a relativistic temperature.
https://www.doczj.com/doc/cf17744113.html,patibility with the two-?ow model
All the previous considerations?nd a natural explanation in the context of the two-?ow model,which was proposed to account for the formation of relativistic jets in AGN:in this model,extragalactic jets are in fact the results of a double structure:a?rst jet,not highly but only mildly relativistic(v≈0.5c),is emitted by a MHD mechanism by a large scale magnetic?eld anchored in an accretion disk(Blandford&Payne1982;Ferreira&Pelletier 1993a,b,1995);this powerful,but weekly dissipative jet,can sustain a MHD turbulence able to accelerate non thermal particles.These particles will produce synchrotron and gamma-rays photons,and if the optical depth becomes large enough,these photons will trigger an intense pair cascade leading to a dense pair plasma in the empty”throat”of the jet.We have shown in previous works that this pair plasma will be spontaneously accelerated to relativistic velocities even if the surrounding jet is not highly relativistic by itself,by the so called”Compton Rocket e?ect”,which is a recoil e?ect associated with anisotropic IC pro-cess originally introduced by Odell(1981).The Compton Rocket e?ect has been shown to be ine?cient to accelerate an isolated relativistic plasma because the cooling time is always shorter than the bulk acceleration time(Phinney1982).In the two-?ow model however,the heating by the surrounding jets compensates for the cooling and the pair plasma remains relativistic over large distances(Marcowith,Henri,&Pelletier1995).
Detailed calculations of the Compton Rocket e?ect in this con?guration(Renaud&
Henri1998)show that the pair plasma accelerates gradually in the vicinity of an accretion
disk,being maintained to a quasi equilibrium Lorentz factorΓbeq≈(z/r i)1/4,where r i is the inner radius of the accretion disk(3gravitational radii for a Schwarschild black hole).
The equilibrium Lorentz factor is de?ned by the fact that the photon?eld of the accretion
disk,seen in the comoving frame,appears to be nearly isotropic due to relativistic aberra-
tion.It grows slowly with the distance,because the?eld becomes more and more anisotropic.
The acceleration continues until the photon density becomes to low to e?ciently accelerate
the plasma.Then the plasma decouples from the ambient radiation?eld and ends up with
an asymptotic balistic motion at constantΓb→Γb∞,which depends on the disk lumi-nosity and the particle energy distribution.For a relativistic energy distribution function n(γ)∝γ2exp(?γ/ˉγ),the asymptotic bulk Lorentz factor is approximatelyΓb∞≈(?sˉγ)1/7, where?s=L sσTh/4πm e c3r i is the soft photon disk compactness andˉγis the characteristic energy of the pileup depending on the details of the acceleration/cooling processes(Renaud &Henri1998).
The?rst interesting feature in this model is that it predicts naturally a gradual accel-eration from the core.The value ofΓb≈3is naturally obtained at≈100r g,which is a typical distance where gamma-ray emission seems to occur,based on variability arguments. Thus low Lorentz factor are not surprising in this model,but are explained naturally.As a matter of fact,very high values of20near the core would be di?cult to explain in this frame!
The second one is that the asymptotic bulk Lorentz factor is controlled by the density of the photon?eld emitted by the accretion disk.For BL Lac objects and FR-I galaxies,the disk luminosity is known to be much lower than luminous FSRQ and FR-II galaxies,by a factor around10?3.One would expect thus a lower asymptotic Lorentz factor for BL Lac object in average,which would help to understand the absence of superluminal motion in TeV blazars.As a matter of fact,numerical estimates show that the expected asymptotic Lorentz factors are between10and20for near-Eddington accreting supermassive black holes, whereas they are rather between5and10for low luminosity AGN.We note that bulk Lorentz factors around5are indeed observed in M87,which would mean that the decoupling occurs at some thousands Schwarzschild radii from the core.Uni?cation models are compatible with slowly accelerating jets,the inner(X-ray emitting)jets having bulk Lorentz factors around3and the outer radio jet having a larger Lorentz factor around7(Urry&Padovani (1995)).Again this is perfectly compatible with the predictions of the two-?ow model,with an inner jet emitting X-ray and TeV radiation with a modest bulk Lorentz factor,and an outer jet responsible for radio emission with a higher one.Also we note that there is no
高二《甜美纯净的女声独唱》教案 一、基本说明 教学内容 1）教学内容所属模块：歌唱 2）年级：高二 3）所用教材出版单位：湖南文艺出版社 4）所属的章节：第三单元第一节 5）学时数： 45 分钟 二、教学设计 1、教学目标： ①、在欣赏互动中感受女声的音域及演唱风格，体验女声的音色特点。 ②、在欣赏互动中，掌握美声、民族、通俗三种唱法的特点，体验其魅力。 ③、让学生能够尝试用不同演唱风格表现同一首歌。 ④、通过学唱歌曲培养学生热爱祖国、热爱生活的激情。 2、教学重点： ①、掌握女高音、女中音的音域和演唱特点。 ②、掌握美声、民族、通俗三种方法演唱风格。 3、教学难点： ①、学生归纳不同唱法的特点与风格。
②、学生尝试用不同演唱风格表现同一首歌。 3、设计思路 《普通高中音乐课程标准》指出：“音乐课的教学过程就是音乐的艺术实践过程。”《甜美纯净的女声独唱》作为《魅力四射的独唱舞台》单元的第一课，是让学生在丰富多彩的歌唱艺术形式中感受出女声独唱以其优美纯净的声音特点而散发出独特的魅力。为此，本课从身边熟悉的人物和情景入手，激发学生学习兴趣，把教学重心放在艺术实践中，让学生在欣赏、学习不同的歌唱风格中，培养自己的综合欣赏能力及歌唱水平。在教学过程中让学生体会不同风格的甜美纯净女声的内涵，感知优美纯净的声音特点而散发出的独特魅力，学会多听、多唱，掌握一定的歌唱技巧，提高自己的演唱水平。为实现以上目标，本人将新课标“过程与方法”中的“体验、比较、探究、合作”四个具体目标贯穿全课，注重学生的个人感受和独特见解，鼓励学生的自我意识与创新精神，强调探究、强调实践，将教学过程变为整合、转化间接经验为学生直接经验的过程，让学生亲身去感悟、去演唱，并力求改变现在高中学生普遍只关注流行歌曲的现状，让学生自己确定最适合自己演唱的方法，自我发现、自我欣赏，充分展示自己的的声音魅力。 三、教学过程 教学环节及时间教师活动学生活动设计意图
教育资料 《短歌行》 《短歌行》赏析(林庚) 曹操这一首《短歌行》是建安时代杰出的名作，它代表着人生的两面，一方面是人生的忧患，一方面是人生的欢乐。而所谓两面也就是人生的全面。整个的人生中自然含有一个生活的态度，这就具体地表现在成为《楚辞》与《诗经》传统的产儿。它一方面不失为《楚辞》中永恒的追求，一方面不失为一个平实的生活表现，因而也就为建安诗坛铺平了道路。 这首诗从“对酒当歌，人生几何”到“但为君故，沉吟至今”，充分表现着《楚辞》里的哀怨。一方面是人生的无常，一方面是永恒的渴望。而“呦呦鹿鸣”以下四句却是尽情的欢乐。你不晓得何以由哀怨这一端忽然会走到欢乐那一端去，转折得天衣无缝，仿佛本来就该是这么一回事似的。这才是真正的人生的感受。这一段如是，下一段也如是。“明明如月，何时可掇?忧从中来，不可断绝。越陌度阡，枉用相存。契阔谈宴，心念旧恩。月明星稀，乌鹊南飞。绕树三匝，何枝可依。”缠绵的情调，把你又带回更深的哀怨中去。但“山不厌高，海不厌深”，终于走入“周公吐哺，天下归心”的结论。上下两段是一个章法，但是你并不觉得重复，你只觉得卷在悲哀与欢乐的旋涡中，不知道什么时候悲哀没有了，变成欢乐，也不知道什么时候欢乐没有了，又变成悲哀，这岂不是一个整个的人生吗?把整个的人生表现在一个刹那的感觉上，又都归于一个最实在的生活上。“我有嘉宾，鼓瑟吹笙”，不正是当时的情景吗?“周公吐哺，天下归心”，不正是当时的信心吗? “青青子衿”到“鼓瑟吹笙”两段连贯之妙，古今无二。《诗经》中现成的句法一变而有了《楚辞》的精神，全在“沉吟至今”的点窜，那是“青青子衿”的更深的解释，《诗经》与《楚辞》因此才有了更深的默契，从《楚辞》又回到《诗经》，这样与《鹿鸣》之诗乃打成一片，这是一个完满的行程，也便是人生旅程的意义。“月明星稀”何以会变成“山不厌高，海不厌深”?几乎更不可解。莫非由于“明月出天山”，“海上生明月”吗?古辞说：“枯桑知天风，海水知天寒”，枯桑何以知天风，因为它高；海水何以知天寒，因为它深。唐人诗“一叶落知天下秋”，我们对于宇宙万有正应该有一个“知”字。然则既然是山，岂可不高?既然是海，岂可不深呢?“并刀如水，吴盐胜雪”，既是刀，就应该雪亮；既是盐，就应该雪白，那么就不必问山与海了。 山海之情，成为漫漫旅程的归宿，这不但是乌鹊南飞，且成为人生的思慕。山既尽其高，海既尽其深。人在其中乃有一颗赤子的心。孟子主尽性，因此养成他浩然之气。天下所以归心，我们乃不觉得是一个夸张。 .
1麦考瑞雅思 已具有近10年英语和雅思培训经验，全国唯一开设在复旦大学城的专业雅思培训机构，唯一雅思承诺保分班，唯一突破中国学生写作口语瘸腿的创新性教学，写作口语成绩普遍高出社会平均分70%左右，唯一每天13小时《雅思高分技巧课+训练课》复合式教学体系，大学氛围，省级重点高中的管理模式，坚持高强度、大容量、出高分，得到了复旦大学高校教师和复旦内部大学生及上海大学生的普遍认可，享有极高的声誉，尤其是在写作口语双7分方面极为擅长。适合零基础、高中生、大学生在短期内的快速突破雅思6—8分。 麦考瑞雅思06年即开始G类移民类雅思培训，对G类雅思5分—8分都有丰富的教学和应试经验，每年都有G类学员在麦考瑞雅思的帮助下，取得了雅思4个6分，4个7分，总分和7分等，成功技术移民或投资移民到澳洲、美国、加拿大、新西兰等国家。 麦考瑞雅思低调而务实，从不做广告，除了江浙沪皖，仍有北京、河北、湖南、四川、内蒙等全国各地学员慕名而来。2010年度，麦考瑞雅思在沪江网被万名（ielts）《2010年度学员最满意的雅思培训机构》，并被央视CCTV、新华网等权威媒体报道班级成功故事，成为上海8万考生雅思7分实战人气排名第一和教学质量最好的专业雅思培训。 2新东方雅思 新东方教育科技集团(New Oriental Education & Technology Group )成立于1993年11月16日。经过十多年的发展，新东方教育科技集团已发展成为一家以外语培训和基础教育为核心，拥有短期语言培训系统、基础教育系统、教育研发系统、出国咨询系统、文化产业系统、科技产业系统等多个发展平台，集教育培训、教育研发、图书杂志音响出版、出国留学服务、国际游学服务，新东方在线教育、教育软件研发等于一体的大型综合性教育科技集团。2006年9月7号，新东方教育科技集团在美国纽约证券交易所成功上市，成为中国第一家在美国上市的教育机构。 3环球雅思
适合女生KTV唱的100首好听的歌别吝色你的嗓音很好学 1、偏爱----张芸京 2、阴天----莫文蔚 3、眼泪----范晓萱 4、我要我们在一起---=范晓萱 5、无底洞----蔡健雅 6、呼吸----蔡健雅 7、原点----蔡健雅&孙燕姿 8、我怀念的----孙燕姿 9、不是真的爱我----孙燕姿 10、我也很想他----孙燕姿 11、一直很安静----阿桑 12、让我爱----阿桑 13、错过----梁咏琪 14、爱得起----梁咏琪 15、蓝天----张惠妹 16、记得----张惠妹 17、简爱----张惠妹 18、趁早----张惠妹 19、一念之间----戴佩妮 20、两难----戴佩妮 21、怎样----戴佩妮 22、一颗心的距离----范玮琪 23、我们的纪念日----范玮琪 24、启程----范玮琪 25、最初的梦想----范玮琪 26、是非题----范玮琪 27、你是答案----范玮琪 28、没那么爱他----范玮琪 29、可不可以不勇敢----范玮琪 30、一个像夏天一个像秋天----范玮琪 31、听，是谁在唱歌----刘若英 32、城里的月光----许美静 33、女人何苦为难女人----辛晓琪 34、他不爱我----莫文蔚 35、你是爱我的----张惠妹 36、同类----孙燕姿 37、漩涡----孙燕姿 38、爱上你等于爱上寂寞----那英 39、梦醒了----那英 40、出卖----那英 41、梦一场----那英 42、愿赌服输----那英
43、蔷薇----萧亚轩 44、你是我心中一句惊叹----萧亚轩 45、突然想起你----萧亚轩 46、类似爱情----萧亚轩 47、Honey----萧亚轩 48、他和他的故事----萧亚轩 49、一个人的精彩----萧亚轩 50、最熟悉的陌生人----萧亚轩 51、想你零点零一分----张靓颖 52、如果爱下去----张靓颖 53、我想我是你的女人----尚雯婕 54、爱恨恢恢----周迅 55、不在乎他----张惠妹 56、雪地----张惠妹 57、喜欢两个人----彭佳慧 58、相见恨晚----彭佳慧 59、囚鸟----彭羚 60、听说爱情回来过----彭佳慧 61、我也不想这样----王菲 62、打错了----王菲 63、催眠----王菲 64、执迷不悔----王菲 65、阳宝----王菲 66、我爱你----王菲 67、闷----王菲 68、蝴蝶----王菲 69、其实很爱你----张韶涵 70、爱情旅程----张韶涵 71、舍得----郑秀文 72、值得----郑秀文 73、如果云知道----许茹芸 74、爱我的人和我爱的人----裘海正 75、谢谢你让我这么爱你----柯以敏 76、陪我看日出----蔡淳佳 77、那年夏天----许飞 78、我真的受伤了----王菀之 79、值得一辈子去爱----纪如璟 80、太委屈----陶晶莹 81、那年的情书----江美琪 82、梦醒时分----陈淑桦 83、我很快乐----刘惜君 84、留爱给最相爱的人----倪睿思 85、下一个天亮----郭静 86、心墙----郭静
曹操《短歌行【对酒当歌】》原文、翻译、赏析译文 原文 面对美酒应该高歌，人生短促日月如梭。对酒当歌，人生几何？ 好比晨露转瞬即逝，失去的时日实在太多！譬如朝露，去日苦多。 席上歌声激昂慷慨，忧郁长久填满心窝。慨当以慷，忧思难忘。 靠什么来排解忧闷？唯有狂饮方可解脱。何以解忧？唯有杜康。 那穿着青领（周代学士的服装）的学子哟，你们令我朝夕思慕。青青子衿，悠悠我心。 正是因为你们的缘故，我一直低唱着《子衿》歌。但为君故，沉吟至今。 阳光下鹿群呦呦欢鸣，悠然自得啃食在绿坡。呦呦鹿鸣，食野之苹。 一旦四方贤才光临舍下，我将奏瑟吹笙宴请宾客。我有嘉宾，鼓瑟吹笙。 当空悬挂的皓月哟，你运转着，永不停止；明明如月，何时可掇？ 我久蓄于怀的忧愤哟，突然喷涌而出汇成长河。忧从中来，不可断绝。 远方宾客踏着田间小路，一个个屈驾前来探望我。越陌度阡，枉用相存。 彼此久别重逢谈心宴饮，争着将往日的情谊诉说。契阔谈讌，心念旧恩。 明月升起，星星闪烁，一群寻巢乌鹊向南飞去。月明星稀，乌鹊南飞。 绕树飞了三周却没敛绕树三匝，何枝
翅，哪里才有它们栖身之 所？ 可依？ 高山不辞土石才见巍 峨，大海不弃涓流才见壮阔。（比喻用人要“唯才是举”，多多益善。）山不厌高，水不厌深。 只有像周公那样礼待贤 才（周公见到贤才，吐出口 中正在咀嚼的食物，马上接 待。《史记》载周公自谓： “一沐三握发，一饭三吐哺， 犹恐失天下之贤。”），才 能使天下人心都归向我。 周公吐哺，天 赏析 曹操是汉末杰出的政治家、军事家和文学家，他雅好诗章，好作乐府歌辞，今存诗22首，全是乐府诗。曹操的乐府诗多描写他本人的政治主张和统一天下的雄心壮志。如他的《短歌行》，充分表达了诗人求贤若渴以及统一天下的壮志。 《短歌行》是政治性很强的诗作，主要是为曹操当时所实行的政治路线和政策策略服务的，但是作者将政治内容和意义完全熔铸在浓郁的抒情意境之中，全诗充分发挥了诗歌创作的特长，准确而巧妙地运用了比兴手法，寓理于情，以情感人。诗歌无论在思想内容还是在艺术上都取得了极高的成就，语言质朴，立意深远，气势充沛。这首带有建安时代"志深比长""梗概多气"的时代特色的《短歌行》，读后不觉思接千载，荡气回肠，受到强烈的感染。 对酒当歌，人生几何？ 譬如朝露，去日苦多。 慨当以慷，幽思难忘。 何以解忧，唯有杜康。 青青子衿，悠悠我心。 但为君故，沈吟至今。 呦呦鹿鸣，食野之苹。 我有嘉宾，鼓瑟吹笙。 明明如月，何时可掇？ 忧从中来，不可断绝。 越陌度阡，枉用相存。 契阔谈，心念旧恩。 月明星稀，乌鹊南飞， 绕树三匝，何枝可依？ 山不厌高，海不厌深， 周公吐哺，天下归心。 《短歌行》是汉乐府的旧题，属于《相和歌?平调曲》。这就是说它本来是一个乐曲的名称，这种乐曲怎么唱法，现在当然是不知道了。但乐府《相和歌?平调曲》中除了《短歌行》还有《长歌行》，唐代吴兢《乐府古题要解》引证古诗“长歌正激烈”，魏文帝曹丕《燕歌行》“短歌微吟不能长”和晋代傅玄《艳歌行》“咄来长歌续短歌”等句，认为“长歌”、“短
外国文学名著鉴赏期末论文院—系：数学学院 科目：外国文学名著鉴赏（期末论文）班级： 08级数学与应用数学A班 姓名：沈铁 学号： 200805050149 上课时段：周五晚十、十一节课
奋斗了，才有出路 ——读《鲁宾逊漂游记》有感小说《鲁宾逊漂游记》一直深受人们的喜爱。读完这篇小说，使我对人生应该有自己的一个奋斗历程而受益匪浅。当一个人已经处于绝境的时候，还能够满怀信心的去面对和挑战生活，实在是一种可贵的精神。他使我认识到，人无论何时何地，不管遇到多大的困难，都不能被困难所吓倒，我们要勇敢的面对困难，克服困难，始终保持一种积极向上、乐观的心态去面对。在当今社会只有努力去奋斗，才会有自己的出路！ 其实现在的很多人都是那些遇到困难就退缩，不敢勇敢的去面对它。不仅如此，现在很多人都是独生子女，很多家长视子女为掌上明珠，不要说是冒险了，就连小小的家务活也不让孩子做，天天总是说：“我的小宝贝啊，你读好书就行了，其它的爸爸妈妈做就可以了。”读书固然重要，但生活中的小事也不能忽略。想一想，在荒无人烟的孤岛上，如果你连家务活都不会做，你能在那里生存吗？读完这部著作后，我不禁反问自己：“如果我像书中的鲁宾逊那样在大海遭到风暴，我能向他那样与风暴搏斗，最后逃离荒岛得救吗？恐怕我早已经被大海所淹没；如果我漂流到孤岛，能活几天？我又能干些什么？我会劈柴吗？会打猎做饭吗？我连洗洗自己的衣服还笨手笨脚的。”我们应该学习鲁宾逊这种不怕困难的精神，无论何时何地都有坚持地活下去，哪怕只有一线希望也要坚持到底，决不能放弃！我们要像鲁宾
逊那样有志气、有毅力、爱劳动，凭自己的双手创造财富，创造奇迹，取得最后的胜利。这样的例子在我们的生活中屡见不鲜。 《史记》的作者司马迁含冤入狱，可它依然在狱中完成《史记》一书，他之所以能完成此书，靠的也是他心中那顽强的毅力，永不放弃的不断努力的精神。著名作家爱迪生从小就生活在一个贫困的家庭中，可是他从小就表现出了科学方面的天赋。长大后爱迪生着力于电灯的发明与研究，他经过了九百多次的失败，可它依然没有放弃，不断努力，最后终于在第一千次实验中取得了成功。 鲁宾逊在岛上生活了二十八年，他面对了各种各样的困难和挫折，克服了许多常人无法想象的困难，自己动手，丰衣足食，以惊人的毅力，顽强的活了下来。他自从大船失事后，找了一些木材，在岛上盖了一间房屋，为防止野兽，还在房子周围打了木桩，来到荒岛，面对着的首要的就是吃的问题，船上的东西吃完以后，鲁宾逊开始打猎，有时可能会饿肚子，一是他决定播种，几年后他终于可以吃到自己的劳动成果，其实学习也是这样，也有这样一个循序渐进的过程，现在的社会，竞争无处不在，我们要懂得只有付出才会有收获，要勇于付出，在战胜困难的同时不断取得好成绩。要知道只有付出，才会有收获。鲁宾逊在失败后总结教训，终于成果；磨粮食没有石磨，他就用木头代替；没有筛子，就用围巾。鲁宾逊在荒岛上解决了自己的生存难题，面对人生挫折，鲁宾逊的所作所为充分显示了他坚毅的性格和顽强的精神。同样我们在学习上也可以做一些创新，养成一种创新精神，把鲁宾逊在荒岛，不畏艰险，不怕失败挫折，艰苦奋斗的精
●中国培训机构排行榜 ● ●根据2013-2014年中国教育培训行业的发展，现在慢慢转向为在线教育，不 再是以前的传统式教育。现在大多数培训机构都是以面授加网授同步进行教学，满足学员需求。 ● ●在这么众多的培训机构里，有加盟的，有连锁的。中国大大小小的培训机构 上万家，到底哪些培训机构最好，最适合我们理想的学习环境。深圳爱培训网为大家整理出以下中国十个最为出色的培训机构！ ● ●一、新东方教育科技集团 ● ●培训项目：英语、厨师、出国留学、托福、雅思等。 ● ● ●
● ●中国培训机构排行榜---新东方教育集团 ● ●学校简介：新东方创办于1993年,20年专注教育培训,累积培训学员超过1600 万,从早教到成人,业务涵盖早教、学前、小学、中学、四六级、考研、出国考试、留学咨询、英语能力提升、国际游学、国际教育、图书、网络课堂等50多所学校,30000多名教职员工,旨在为学员提供一站式终身学习服务。 ● ●新东方教育科技集团已发展为一家以外语培训和基础教育为核心，拥有短期 语言培训系统、基础教育系统、职业教育系统、教育研发系统、出国咨询系统、文化产业系统、科技产业系统等多个发展平台，集教育培训、教育研发、图书杂志音响出版、出国留学服务、职业教育、新东方在线教育、教育软件研发等于一体的大型综合性教育科技集团。 ● ●学校优势：网授+面授同步进行、学校师资力量雄厚，中国老品牌教育培训 机构。 ● ●二、学而思教育 ● ●培训项目：小学奥数、英语、语文，初高中数学、物理、化学、英语、语文。●
● ● ●中国培训机构排行榜---学而思中小学教育 ● ●学校简介：2010年10月20日，学而思教育在纽约证券交易所正式挂牌交易， 成为国内首家在美国上市的中小幼课外教育培训机构。 ● ●学而思以“给孩子受益一生的教育”为使命，秉承“激发兴趣、培养习惯、 塑造品格”的教育理念，不仅关注学生学习成绩的提高，更关注学生学习兴趣的激发、学习习惯的培养和思维模式的塑造。为满足孩子多元的教育需求，学而思开展小班、1对1、网校等多种形式的教育服务，旗下拥有摩比思维馆、学而思培优、学而思网校、智康1对1、E度教育网五个子业务品牌，在各自细分领域都处于领先地位。 ● ●学而思还发展了国内布局完整的中小幼教育专业门户网站群——e度教育 网。e度网由育儿网、幼教网、奥数网、中考网、高考网、留学网等多个网
曹操《短歌行》其二翻译及赏析 引导语：曹操(155—220)，字孟德，小名阿瞒，《短歌行 二首》 是曹操以乐府古题创作的两首诗， 第一首诗表达了作者求贤若渴的心 态，第二首诗主要是曹操向内外臣僚及天下表明心迹。 短歌行 其二 曹操 周西伯昌，怀此圣德。 三分天下，而有其二。 修奉贡献，臣节不隆。 崇侯谗之，是以拘系。 后见赦原，赐之斧钺，得使征伐。 为仲尼所称，达及德行， 犹奉事殷，论叙其美。 齐桓之功，为霸之首。 九合诸侯，一匡天下。 一匡天下，不以兵车。 正而不谲，其德传称。 孔子所叹，并称夷吾，民受其恩。 赐与庙胙，命无下拜。 小白不敢尔，天威在颜咫尺。 晋文亦霸，躬奉天王。 受赐圭瓒，钜鬯彤弓， 卢弓矢千，虎贲三百人。 威服诸侯，师之所尊。 八方闻之，名亚齐桓。 翻译 姬昌受封为西伯，具有神智和美德。殷朝土地为三份，他有其中两分。 整治贡品来进奉，不失臣子的职责。只因为崇侯进谗言，而受冤拘禁。 后因为送礼而赦免， 受赐斧钺征伐的权利。 他被孔丘称赞， 品德高尚地位显。 始终臣服殷朝帝王，美名后世流传遍。齐桓公拥周建立功业，存亡继绝为霸 首。
聚合诸侯捍卫中原，匡正天下功业千秋。号令诸侯以匡周室，主要靠的不是 武力。 行为磊落不欺诈，美德流传于身后。孔子赞美齐桓公，也称赞管仲。 百姓深受恩惠，天子赐肉与桓公，命其无拜来接受。桓公称小白不敢，天子 威严就在咫尺前。 晋文公继承来称霸，亲身尊奉周天王。周天子赏赐丰厚，仪式隆重。 接受玉器和美酒，弓矢武士三百名。晋文公声望镇诸侯，从其风者受尊重。 威名八方全传遍，名声仅次于齐桓公。佯称周王巡狩，招其天子到河阳，因 此大众议论纷纷。 赏析 《短歌行》 (“周西伯昌”)主要是曹操向内外臣僚及天下表明心 迹，当他翦灭群凶之际，功高震主之时，正所谓“君子终日乾乾，夕惕若 厉”者，但东吴孙权却瞅准时机竟上表大说天命而称臣，意在促曹操代汉 而使其失去“挟天子以令诸侯”之号召， 故曹操机敏地认识到“ 是儿欲据吾著炉上郁!”故曹操运筹谋略而赋此《短歌行 ·周西伯 昌》。 西伯姬昌在纣朝三分天下有其二的大好形势下， 犹能奉事殷纣， 故孔子盛称 “周之德， 其可谓至德也已矣。 ”但纣王亲信崇侯虎仍不免在纣王前 还要谗毁文王，并拘系于羑里。曹操举此史实，意在表明自己正在克心效法先圣 西伯姬昌，并肯定他的所作所为，谨慎惕惧，向来无愧于献帝之所赏。 并大谈西伯姬昌、齐桓公、晋文公皆曾受命“专使征伐”。而当 今天下时势与当年的西伯、齐桓、晋文之际颇相类似，天子如命他“专使 征伐”以讨不臣，乃英明之举。但他亦效西伯之德，重齐桓之功，戒晋文 之诈。然故作谦恭之辞耳，又谁知岂无更讨封赏之意乎 ?不然建安十八年(公元 213 年)五月献帝下诏曰《册魏公九锡文》，其文曰“朕闻先王并建明德， 胙之以土，分之以民，崇其宠章，备其礼物，所以藩卫王室、左右厥世也。其在 周成，管、蔡不静，惩难念功，乃使邵康公赐齐太公履，东至于海，西至于河， 南至于穆陵，北至于无棣，五侯九伯，实得征之。 世祚太师，以表东海。爰及襄王，亦有楚人不供王职，又命晋文登为侯伯， 锡以二辂、虎贲、斧钺、禾巨 鬯、弓矢，大启南阳，世作盟主。故周室之不坏， 系二国是赖。”又“今以冀州之河东、河内、魏郡、赵国、中山、常 山，巨鹿、安平、甘陵、平原凡十郡，封君为魏公。锡君玄土，苴以白茅，爰契 尔龟。”又“加君九锡，其敬听朕命。” 观汉献帝下诏《册魏公九锡文》全篇，尽叙其功，以为其功高于伊、周，而 其奖却低于齐、晋，故赐爵赐土，又加九锡，奖励空前。但曹操被奖愈高，心内 愈忧。故曹操在曾早在五十六岁写的《让县自明本志令》中谓“或者人见 孤强盛， 又性不信天命之事， 恐私心相评， 言有不逊之志， 妄相忖度， 每用耿耿。
（一）文学常识 一、古希腊罗马 1．（1）宙斯(罗马神话称为朱庇特)，希腊神话中最高的天神，掌管雷电云雨，是人和神的主宰。 （2）阿波罗，希腊神话中宙斯的儿子，主管光明、青春、音乐、诗歌等，常以手持弓箭的少年形象出现。 （3）雅典那，希腊神话中的智慧女神，雅典城邦的保护神。 （4）潘多拉，希腊神话中的第一个女人，貌美性诈。私自打开了宙斯送她的一只盒子，里面装的疾病、疯狂、罪恶、嫉妒等祸患，一齐飞出，只有希望留在盒底，人间因此充满灾难。“潘多拉的盒子”成为“祸灾的来源”的同义语。 （5）普罗米修斯，希腊神话中造福人间的神。盗取天火带到人间，并传授给人类多种手艺，触怒宙斯，被锁在高加索山崖，受神鹰啄食，是一个反抗强暴、不惜为人类牺牲一切的英雄。 （6）斯芬克司，希腊神话中的狮身女怪。常叫过路行人猜谜，猜不出即将行人杀害；后因谜底被俄底浦斯道破，即自杀。后常喻“谜”一样的人物。与埃及狮身人面像同名。 2．荷马，古希腊盲诗人。主要作品有《伊利亚特》和《奥德赛》，被称为荷马史诗。《伊利亚特》叙述十年特洛伊战争。《奥德赛》写特洛伊战争结束后，希腊英雄奥德赛历险回乡的故事。马克思称赞它“显示出永久的魅力”。 3．埃斯库罗斯，古希腊悲剧之父，代表作《被缚的普罗米修斯》。6．阿里斯托芬，古希腊“喜剧之父”代表作《阿卡奈人》。 4．索福克勒斯，古希腊重要悲剧作家，代表作《俄狄浦斯王》。5．欧里庇得斯，古希腊重要悲剧作家，代表作《美狄亚》。 二、中世纪文学 但丁，意大利人，伟大诗人，文艺复兴的先驱。恩格斯称他是“中世纪的最后一位诗人，同时又是新时代的最初一位诗人”。主要作品有叙事长诗《神曲》，由地狱、炼狱、天堂三部分组成。《神曲》以幻想形式，写但丁迷路，被人导引神游三界。在地狱中见到贪官污吏等受着惩罚，在净界中见到贪色贪财等较轻罪人，在天堂里见到殉道者等高贵的灵魂。 三、文艺复兴时期 1．薄迦丘意大利人短篇小说家，著有《十日谈》拉伯雷，法国人，著《巨人传》塞万提斯，西班牙人,著《堂?吉诃德》。 2．莎士比亚，16-17世纪文艺复兴时期英国伟大的剧作家和诗人，主要作品有四大悲剧——《哈姆雷特》、《奥赛罗》《麦克白》、《李尔王》，另有悲剧《罗密欧与朱丽叶》等，喜剧有《威尼斯商人》《第十二夜》《皆大欢喜》等，历史剧有《理查二世》、《亨利四世》等。马克思称之为“人类最伟大的戏剧天才”。 四、17世纪古典主义 9．笛福，17-18世纪英国著名小说家，被誉为“英国和欧洲小说之父”，主要作品《鲁滨逊漂流记》，是英国第一部现实主义长篇小说。10．弥尔顿，17世纪英国诗人，代表作：长诗《失乐园》，《失乐园》，表现了资产阶级清教徒的革命理想和英雄气概。 25．拉伯雷，16世纪法国作家，代表作：长篇小说《巨人传》。 26．莫里哀，法国17世纪古典主义文学最重要的作家，法国古典主义喜剧的创建者，主要作品为《伪君子》《悭吝人》（主人公叫阿巴公）等喜剧。 五、18世纪启蒙运动 1）歌德，德国文学最高成就的代表者。主要作品有书信体小说《少年维特之烦恼》，诗剧《浮士德》。 11．斯威夫特，18世纪英国作家，代表作：《格列佛游记》，以荒诞的情节讽刺了英国现实。 12．亨利·菲尔丁，18世纪英国作家，代表作：《汤姆·琼斯》。 六、19世纪浪漫主义 （1拜伦， 19世纪初期英国伟大的浪漫主义诗人，代表作为诗体小说《唐璜》通过青年贵族唐璜的种种经历，抨击欧洲反动的封建势力。《恰尔德。哈洛尔游记》 （2雨果，伟大作家，欧洲19世纪浪漫主义文学最卓越的代表。主要作品有长篇小说《巴黎圣母院》、《悲惨世界》、《笑面人》、《九三年》等。《悲惨世界》写的是失业短工冉阿让因偷吃一片面包被抓进监狱，后改名换姓，当上企业主和市长，但终不能摆脱迫害的故事。《巴黎圣母院》 弃儿伽西莫多，在一个偶然的场合被副主教克洛德.孚罗洛收养为义子，长大后有让他当上了巴黎圣母院的敲钟人。他虽然十分丑陋而且有多种残疾，心灵却异常高尚纯洁。 长年流浪街头的波希米亚姑娘拉.爱斯梅拉达，能歌善舞，天真貌美而心地淳厚。青年贫诗人尔比埃尔.甘果瓦偶然同她相遇，并在一个更偶然的场合成了她名义上的丈夫。很有名望的副教主本来一向专心于"圣职"，忽然有一天欣赏到波希米亚姑娘的歌舞，忧千方百计要把她据为己有，对她进行了种种威胁甚至陷害，同时还为此不惜玩弄卑鄙手段，去欺骗利用他的义子伽西莫多和学生甘果瓦。眼看无论如何也实现不了占有爱斯梅拉达的罪恶企图，最后竟亲手把那可爱的少女送上了绞刑架。 另一方面，伽西莫多私下也爱慕着波希米亚姑娘。她遭到陷害，被伽西莫多巧计救出，在圣母院一间密室里避难，敲钟人用十分纯朴和真诚的感情去安慰她，保护她。当她再次处于危急中时，敲钟人为了援助她，表现出非凡的英勇和机智。而当他无意中发现自己的"义父"和"恩人"远望着高挂在绞刑架上的波希米亚姑娘而发出恶魔般的狞笑时，伽西莫多立即对那个伪善者下了最后的判决，亲手把克洛德.孚罗洛从高耸入云的钟塔上推下，使他摔的粉身碎骨。 （3司汤达，批判现实主义作家。代表作《红与黑》，写的是不满封建制度的平民青年于连，千方百计向上爬，最终被送上断头台的故事。“红”是将军服色，指“入军界”的道路；“黑”是主教服色，指当神父、主教的道路。 14．雪莱，19世纪积极浪漫主义诗人，欧洲文学史上最早歌颂空想社会主义的诗人之一，主要作品为诗剧《解放了的普罗米修斯》，抒情诗《西风颂》等。 15．托马斯·哈代，19世纪英国作家，代表作：长篇小说《德伯家的苔丝》。 16．萨克雷，19世纪英国作家，代表作：《名利场》 17．盖斯凯尔夫人，19世纪英国作家，代表作：《玛丽·巴顿》。 18．夏洛蒂?勃朗特，19世纪英国女作家，代表作：长篇小说《简?爱》19艾米丽?勃朗特，19世纪英国女作家，夏洛蒂?勃朗特之妹，代表作：长篇小说《呼啸山庄》。 20．狄更斯，19世纪英国批判现实主义文学的重要代表，主要作品为长篇小说《大卫?科波菲尔》、《艰难时世》《双城记》《雾都孤儿》。21．柯南道尔，19世纪英国著名侦探小说家，代表作品侦探小说集《福尔摩斯探案》是世界上最著名的侦探小说。 七、19世纪现实主义 1、巴尔扎克，19世纪上半叶法国和欧洲批判现实主义文学的杰出代表。主要作品有《人间喜剧》，包括《高老头》、《欧也妮·葛朗台》、《贝姨》、《邦斯舅舅》等。《人间喜剧》是世界文学中规模最宏伟的创作之一，也是人类思维劳动最辉煌的成果之一。马克思称其“提供了一部法国社会特别是巴黎上流社会的卓越的现实主义历史”。
2019-2020年高一音乐甜美纯净的女声独唱教案 一、教学目标 1、认知目标：初步了解民族唱法、美声唱法、通俗唱法三种唱法的风格。 2、能力目标：通过欣赏部分女声独唱作品，学生能归纳总结出她们的演唱 风格和特点，并同时用三种不同风格演唱同一首歌曲。 3、情感目标：通过欣赏比较，对独唱舞台有更多元化的审美意识。 二、教学重点：学生能用三种不同风格演唱形式演唱同一首歌。 三、教学难点：通过欣赏部分女声独唱作品，学生能归纳总结出她们的演唱 风格和特点。 四、教学过程： （一）导入 1、播放第十三界全国青年歌手大奖赛预告片 （师）问：同学们对预告片中的歌手认识吗 （生）答： （师）问：在预告片中提出了几种唱法？ （生）答：有民族、美声、通俗以及原生态四种唱法，今天以女声独唱歌曲重点欣赏民族、美声、通俗唱法，希望通过欣赏同学们能总结出三种唱法的风格和特点。 （二）、音乐欣赏
1、通俗唱法 ①(师)问：同学们平常最喜欢唱那些女歌手的歌呢？能唱唱吗？ （可让学生演唱几句喜欢的歌，并鼓励） ②欣赏几首通俗音乐 视频一：毛阿敏《绿叶对根的情谊》片段、谭晶《在那东山顶上》片段、韩红《天路》片段、刘若英《后来》片段 视频二：超女《想唱就唱唱得响亮》 ①由学生总结出通俗音乐的特点 ②师总结并板书通俗音乐的特点：通俗唱法是在演唱通俗歌曲的基础上发展起来的，又称“流行唱法”。通俗歌曲是以通俗易懂、易唱易记、娱乐性强、便于流行而见长，它没有统一的规格和演唱技法的要求，比较强调歌唱者本人的自然嗓音和情绪的渲染，重视歌曲感情的表达。演唱上要求吐字清晰，音调流畅，表情真挚，带有口语化。 ③指出通俗音乐尚未形成系统的发声训练体系。其中用沙哑、干枯的音色“狂唱”和用娇柔、做作的姿态“嗲唱”，不属于声乐艺术的正道之物，应予以摒弃。 2、民族唱法 ①俗话说民族的才是世界的那么民族唱法的特点是什么呢？ ②欣赏彭丽媛《万里春色满人间》片段 鉴赏提示：这首歌是剧种女主角田玉梅即将走上刑场时的一段难度较大的咏叹调。
题目：浅析从简爱到女性的尊严和爱 学院工商学院 专业新闻学3 学号 姓名闫万里 学科外国文学名着赏析 [摘要] 十九世纪中期，英国伟大的女性存在主义先驱，着名作家夏洛蒂勃朗特创作出了她的代表作--《简爱》，当时轰动了整个文坛,它是一部具有浓厚浪漫主义色彩的现实主义小说，被认为是作者"诗意的生平"的写照。它在问世后的一百多年里，它始终保持着历史不败的艺术感染力。直到现在它的影响还继续存在。在作品的序幕、发展、高潮和结尾中，女主人公的叛逆、自由、平等、自尊、纯洁的个性都是各个重点章节的主旨，而这些主旨则在女主人公的爱情观中被展露的淋漓尽致，它们如同乌云上方的星汉，灼灼闪耀着光芒，照亮着后来的女性者们追求爱情的道路。? [关键词] 自尊个性独特新女性主义自由独立平等 《简爱》是一部带有自转色彩的长篇小说，它阐释了这样一个主题：人的价值=尊严+爱。从小就成长在一个充满暴力的环境中的简爱，经历了同龄人没有的遭遇。她要面对的是舅妈的毫无人性的虐待，表兄的凶暴专横和表姐的傲慢冷漠，尽管她尽力想“竭力赢得别人的好感”，但是事实告诉她这都是白费力气的，因此她发出了“不公平啊！--不公平！”的近乎绝望的呼喊。不公平的生长环境，使得简爱从小就向往平等、自由和爱，这些愿望在她后来的成长过程中表现无疑，
譬如在她的爱情观中的种种体现。? 1.桑菲尔德府? 谭波儿小姐因为出嫁，离开了洛伍德学校，同时也离开了简爱，这使简爱感觉到了“一种稳定的感觉，一切使我觉得洛伍德学校有点像我家的联想，全都随着她消失了”，她意识到：真正的世界是广阔的，一个充满希望和忧虑、激动和兴奋的变化纷呈的天地，正等待着敢于闯入、甘冒风险寻求人生真谛的人们。意识形态的转变促使着简爱走向更广阔的社会，接受社会的挑战，尽管她才只有十八岁。于是，简爱来到了桑菲尔德府，当了一名在当时地位不高的家庭教师。?桑菲尔德府使简爱感受到“这儿有想象中的完美无缺的家庭安乐气氛”，事实证明了她的预感的正确性，。从和简爱相见、相识到相爱的过程当中，简爱的那种叛逆精神、自强自尊的品质深深地征服了罗切斯特，而罗切斯特的优雅风度和渊博知识同样也征服了简爱。最初开始，简爱一直以为罗切斯特会娶高贵漂亮的英格拉姆为妻，她在和罗切斯特谈到婚姻时，曾经义正言辞的对罗切斯特说：“你以为因为我穷，低微，不美，矮小，就没有灵魂了吗？你想错了！我跟你一样有灵魂—也同样有一颗心！我现在不是凭着肉体凡胎跟你说话，而是我的心灵在和你的心灵说话，就好像我们都已经离开人世，两人平等地站在上帝面前—因为我们本来就是平等的。”这充分表现出简爱的叛逆，她这种维护妇女独立人格、主张婚姻独立自主以及男女平等的主张可以看成是他对整个人类社会自由平等的向往追求，罗切斯特正是爱上了她这样的独特个性，同时他也同样重复道：我们本来就是平等的。罗切斯特自始自终爱的是简爱的心灵—有着意志的力量，美德和纯洁的心灵，正是基于如此，简爱才真正的爱着罗切斯特。因为爱情是来不得半点虚假的，一方为另一方付出了真情的爱，假如得到对方的是虚情假意，那么这份爱
短歌行赏析介绍 说道曹操， 大家一定就联想到三国那些烽火狼烟岁月吧。 但是曹操其实也是 一位文学 大家，今天就来分享《短歌行 》赏析。 《短歌行》短歌行》是汉乐府旧题，属于《相和歌辞·平调曲》。这就是说 它本来是一个乐曲名称。最初古辞已经失传。乐府里收集同名诗有 24 首，最早 是曹操这首。 这种乐曲怎么唱法， 现在当然是不知道。 但乐府 《相和歌·平调曲》 中除《短歌行》还有《长歌行》，唐代吴兢《乐府古题要解》引证古诗 “长歌正激烈”， 魏文帝曹丕 《燕歌行》 “短歌微吟不能长”和晋代傅玄 《艳 歌行》 “咄来长歌续短歌”等句， 认为“长歌”、 “短歌”是指“歌声有长短”。 我们现在也就只能根据这一点点材料来理解《短歌行》音乐特点。《短歌行》这 个乐曲，原来当然也有相应歌辞，就是“乐府古辞”，但这古辞已经失传。现在 所能见到最早《短歌行》就是曹操所作拟乐府《短歌行》。所谓“拟乐府”就是 运用乐府旧曲来补作新词，曹操传世《短歌行》共有两首，这里要介绍是其中第 一首。 这首《短歌行》主题非常明确，就是作者希望有大量人才来为自己所用。曹 操在其政治活动中，为扩大他在庶族地主中统治基础，打击反动世袭豪强势力， 曾大力强调“唯才是举”，为此而先后发布“求贤令”、“举士令”、“求逸才 令”等;而《短歌行》实际上就是一曲“求贤歌”、又正因为运用诗歌 形式，含有丰富抒情成分，所以就能起到独特感染作用，有力地宣传他所坚 持主张，配合他所颁发政令。 《短歌行》原来有“六解”(即六个乐段)，按照诗意分为四节来读。 “对酒当歌，人生几何?譬如朝露，去日苦多。慨当以慷，忧思难忘。何以 解忧，唯有杜康。” 在这八句中，作者强调他非常发愁，愁得不得。那么愁是什么呢?原来他是 苦于得不到众多“贤才”来同他合作， 一道抓紧时间建功立业。 试想连曹操这样 位高权重人居然在那里为“求贤”而发愁， 那该有多大宣传作用。 假如庶族地主 中真有“贤才”话， 看这些话就不能不大受感动和鼓舞。 他们正苦于找不到出路
外国文学名著赏析 ——对《哈姆雷特》与《堂吉诃德》人物形象及其现实意义的 分析 班级：学号：姓名： 摘要：《哈姆雷特》和《堂吉诃德》是文艺复兴时期涌现出来的一批比较先进的文学作品，通过对两部文学作品的阅读，我们不难发现两部作品所展现出来的人物形象都反映出了当时不同的社会现实，而且两部文学作品都表现出了浓厚的人文主义色彩，并且在当时也带来了不同的社会作用。堂吉诃德是塞万提斯塑造的一个为了打击骑士文学的文学形象，作者通过对堂吉诃德的描写，生动的说明了骑士文学给世人带来的负面影响，从而给骑士文学以致命的打击。莎士比亚笔下的哈姆雷特则是一个孤独的人文主义者，他以失败告终，哈姆雷特的失败向人们揭示了人文主义时代的悲剧。 Abstract: Hamlet a nd Don Quixote were the advanced literary in the Renaissance Period .After read the two novels, it is not difficult to find that different characters in these novels reflected different social problems. And they all expressed the ideas of humanism. These two images also brought different social functions at that time .Don Quixote is one of which Cervantes’s molds in order to attack the knight literature .According to the description of Don Quixote, vivid explain ed that knight literature brought a serious of bad influence to the human beings, thus gives the knight literature by the fatal attack. Hamlet is a lonely humanism, he is end in failure .His failure has indicated the tragedy which in the Humanism Era. 关键词：人文主义、哈姆雷特、人物形象、艺术特色、堂吉诃德、现实意义、悲剧 Key words:humanism; Hamlet; characters; art features; Don Quixote; realistic significance; tragedy 前言： 莎士比亚和塞万提斯都是文艺复兴时期伟大的戏剧家，作为戏剧艺术的大师，他们的作品都达到了世界文学的巅峰。《哈姆雷特》是莎士比亚最著名的悲剧之一，代表了莎士比亚的艺术成就，剧中莎士比亚塑造的著名人物哈姆雷特也被列入了世界文学的艺术画廊。塞万提斯是文艺复兴时期西班牙伟大的作家，在他创作的作品中，以《堂吉诃德》最为著名，影响也最大，是文艺
哪个雅思培训机构最好？ 哪个雅思培训班好？哪个雅思培训机构最好这应该是广大考雅思们最关注的问题。每次看到都是感触良多，我想到大家选择雅思培训学校的心情的时候，就真的想借给每位雅思考生一双慧眼，让他们把这些培训学校都看的清清楚楚、明明白白。 雅思考试费用不菲，培训价格更高，简直可以说高的离谱，学费几千甚至上万的雅思培训学校比比皆是。那如何选择雅思培训学校呢？我总结了以下几点注意事项，希望对大家有帮助。 一、雅思培训机构的口碑 俗话说得好：金杯，银杯，不如老百姓的口碑！选择雅思培训机构之前一定要多听取周围参加过培训同学的意见，做到心中有数。而对于通过网络搜索学校好坏的同学，一定要谨慎，慎重选择，因为网络上的职业枪手无以计数。 二、学校的师资 目前国内有很多知名雅思培训机构，其中不乏连锁或者加盟的，多数培训学校的老师都是本土化，如果哪家学校的宣传上给老师的包装冠以“北京”，“著名”，“学者”之类的名师，大家可要留意了，很多都是假的。其次老师的稳定性，如果学校的授课老师不断变换，对培训效果就会无法保障，报培训班之前一定要了解授课老师情况，有
的学校虽然打出了什么外教或者是名师的招牌，其实这些老师甚至连从业资格都没有这样我们怎么期待他们能给我带来英语能力的提高！ 三、雅思学校课程设置 专业的雅思学校会根据学生不同英语基础开设课程，例如长期班、基础班、提高班、强化班等。这里建议大家最好选择一对一的雅思课程，在教学上会更有针对性，学习效果也显著。如果基础不同，采取一勺烩的做法，那你需要敬而远之。 四、能为学员提供相关服务 一个专业的雅思培训学校，会为学员提供很多的专业服务。例如：雅思写作批改，雅思口语交流机会，学前、学中、学后的模考等等。如果能提供这些服务并贯穿整个雅思学习的过程，那你可以优先选择了！ 作为中国在线英语培训的领先者，引入欧美授课新理念，一直以来都认真聆听学员的心声，专注于提高学员的英语口语能力，使之成为最高性价比抉择的首选出国前英语雅思培训机构。易格英语利用专门的音频视频软件，通过在线学习的形式为学员提供一对一的专业辅导。他们最大的特色就是英美专业外教，一对一辅导以及免费试听。因为是在线培训的方式，所以培训不受时间、地点的限制，因为省去了场地和往返的费用，真正做到为每位学员节省每一分钱。全国官
短歌行赏析 《短歌行》 对酒当歌，人生几何？譬如朝露，去日苦多。 概当以慷，忧思难忘。何以解忧？唯有杜康。 青青子衿，悠悠我心。但为君故，沈吟至今。 呦呦鹿鸣，食野之苹。我有嘉宾，鼓瑟吹笙。 明明如月，何时可掇？忧从中来，不可断绝。 越陌度阡，枉用相存。契阔谈咽，心念旧恩。 月明星稀，乌鹊南飞。绕树三匝，何枝可依。 山不厌高，海不厌深，周公吐哺，天下归心。 “短歌行”是汉乐府一个曲调的名称，是用于宴会场合的歌辞。曹操集子里现存《短歌行》两首，课文选的是第一首。作为一位政治家兼军事家的诗人曹操，十分重视人才，这首诗抒发了他渴望招纳贤才、建功立业的宏图大愿。 全诗三十二句，分四节，每八句一节。 第一节抒写诗人人生苦短的忧叹。“对酒当歌，人生几何？譬如朝露，去日苦多。”“当”，对着。“去日”，指逝去的岁月。这四句意思是：在边喝着酒，边唱着歌时，忽然感叹道：人生能有多久呢？人生啊，就好比早晨的露水，一会儿就干了，又苦于过去的日子太多了。“慨当以慷，忧思难忘。何以解忧？唯有杜康。”“慨当以慷”是“慷慨”的间隔用法，“当以”，没有实在意义，即指宴会上歌声慷慨激昂。“杜康”相传是发明酿酒的人，这里作酒的代称。这四句意思是：即使宴会上歌声慷慨激昂，诗人内心的忧愁还是难以消除。用什么来消除胸中的忧愁呢？只有借酒浇愁。我们如何理解诗人这种人生苦短的忧叹呢？诗人生逢乱世，
目睹百姓颠沛流离，肝肠寸断，渴望建功立业而不得，因而发出人生苦短的忧叹。这个点我们可从他的另一首诗《蒿里行》中得到佐证：“白骨露于野，千里无鸡鸣。生民百遗一，念之断人肠。” 第二节抒写诗人对贤才的渴求。“青青子衿，悠悠我心”，是引用《诗经?郑风?子衿》中的成句。“青衿”，周代读书人的服装，这里指代有学问的人。“悠悠”，长久的样子，形容思念之情。这两句意思是：你的衣领青青啊，总是让我如此挂念。原诗后两句是：“纵我不往，子宁不嗣音？”意思是：虽然我不能去找你，你为什么不主动给我音信？曹操因为事实上不可能一个一个地去找那些贤才，所以他使用这种含蓄的话来提醒他们，希望贤才主动来归。“但为君故，沉吟至今。”“沉吟”，低声叨念，表示渴念。这两句意思是：只因为你的缘故，让我渴念到如今。“青青子衿，悠悠我心。但为君故，沉吟至今。”四句以女子对心爱的男子的思念比喻自己对贤才的渴求。“呦呦鹿鸣，食野之苹。我有嘉宾，鼓瑟吹笙。”这四句引自《诗经?小雅?鹿鸣》，《鹿鸣》是一首描写贵族盛宴热情款待尊贵客人的的诗歌。前两句起兴，意思是：野鹿呦呦呦呦地叫，欢快地吃着野地里的艾蒿。以下各句描写宾客欢宴的场面，这里引用的两句意思是：我有很多尊贵的客人，席间弹起琴瑟，吹起笙乐。诗人引用这几句诗，表示自己对贤才的热情。 第三节抒写诗人对贤才难得的忧思和既得贤才的欣喜。“明明如月，何时可掇？”“明月”，比喻人才。“掇”，拾取，摘取。意思是：贤才有如天上的明月，我什么时候才能摘取呢？“忧从中来，不可断绝。”因为求才不得，内心不禁产生忧愁，这种忧愁无法排解。“越陌度阡，枉用相存。契阔谈讌，心念旧 恩。”“陌”、“阡”，都是指田间小路，东西向叫“陌”，南北向叫“阡”。“枉”，枉驾，屈驾。“用”，以。“存”，探问，问候。“契阔”，久别重逢。