International Journal of Impact Engineering 35(2008)644–658
The mechanical behaviour of aluminium foam structures in different
loading conditions $
Lorenzo Peroni,Massimiliano Avalle ?,Marco Peroni
Dipartimento di Meccanica,Politecnico di Torino,Corso Duca degli Abruzzi 24,10129Torino (TO),Italy
Received 6September 2006;received in revised form 10January 2007;accepted 28February 2007
Available online 24March 2007
Abstract
The use of foam has the potential for energy absorption enhancement.Many types of materials can be produced in the form of foams,including metals and polymers.Of the metallic based foams,aluminium based are among the most advanced.Aluminium foams couple good speci?c mechanical properties with high thermal stability.Among the various aspects still to be investigated regarding their mechanical behaviour is the in?uence of a hydrostatic state of stress on yield strength.Unlike metals,the hydrostatic component affects yields.Therefore,different loading conditions have to be considered to fully identify the material behaviour.Another important issue in foam structure design is the analysis of composite structures.The mechanical behaviour of an aluminium foam has been examined.The foam was subjected to uniaxial,hydrostatic stress,pure deviatoric stress,and combinations thereof.Results obtained will be presented as quasi-static and dynamic uniaxial compression and quasi-static bending and shear loading.Moreover,composite structures were made by assembling the foam into aluminium cold extruded closed section 6060aluminium tubes.The results show that the energy absorption capability of the composite structures is much greater than the sum of the energy absorbed by the two components,the foam and the tube.
r 2007Elsevier Ltd.All rights reserved.
Keywords:Structural foams;Passive safety materials;High strain-rate material testing;Hydrostatic testing
1.Introduction
In the past 10years many new processes for making foamed metals,mostly aluminium or aluminium alloys,have been developed.Research has led to the commercia-lization of several products.Closed-cell aluminium foam offers a unique combination of properties such as low density,high stiffness,strength,and energy absorption capability.Among the various possible applications,some are common to other types of foams.Main ?eld of use is the energy absorption and dissipation for passive safety systems.Aluminium foams have superior performance in terms of energy absorption with respect to polymeric foams,even considering the greater weight per volume
unit.One of the advantages in using metal foams,like aluminium foams,is the greater range of allowable temperatures:for polymers the limit is around 1001C,whereas for aluminium foams the limit is ?ve times larger.One of the main differences in the mechanical behaviour of cellular materials with respect to classical homogeneous materials is that foam failure is not independent from a hydrostatic state of stress [1–13].Therefore,it is not possible to describe the failure from a single mechanical test and failure criterion.The maximum distortion energy or von Mises criterion rely on the evaluation of the deviatoric component of stress,a consequence that strength in compression is different from strength in tension.So,it is necessary to perform tests with different combination of deviatoric and hydrostatic stress states.As is well known,the hydrostatic component of stress s hyd is the ?rst stress invariant de?ned as [14,15]s hyd ?es 1ts 2ts 3T=3?es x ts y ts z T=3.
(1)
https://www.doczj.com/doc/f61720445.html,/locate/ijimpeng
0734-743X/$-see front matter r 2007Elsevier Ltd.All rights reserved.doi:10.1016/j.ijimpeng.2007.02.007
$
With contributions to the Symposium on Design and Analysis of Advanced Structures,8th Biennial ASME Conference on Engineering Systems Design and Analysis,July 4–7,2006,Torino,Italy.
?Corresponding author.Tel.:+390161226373;fax:+390161226322.E-mail address:massimiliano.avalle@polito.it (M.Avalle).
Equally known is the concept of the deviatoric component of stress s dev,which is the octahedral tangential stress:
s0 dev ?1
?????????????????????????????????????????????????????????????????????????
es1às2T2tes2às3T2tes3às1T2
q
.(2)
A test that gives pure deviatoric stress is,for example,a
shear test(s hyd?0,s0
dev ?t=
p
3).A test that produces
pure hydrostatic stress in the material is the hydrostatic or
triaxial test(s hyd?àp/3,s0
dev ?0).A tensile test gives a
combination of deviatoric and hydrostatic stress compo-
nents s0
dev =s hyd?
p
2,differing from the compression
components by sign:s0
dev =s hyd?à
p
2.
However,for ease of analysis the von Mises effective stress is used in this work as the deviatoric stress parameter,differing from the real deviatoric stress by a factor of(O2/3):
s dev?1??2p
?????????????????????????????????????????????????????????????????????????
es1às2T2tes2às3T2tes3às1T2
q
s VM.
(3)
Thus,a tensile test corresponds to a ratio of the deviatoric and hydrostatic stress components:s dev/s hyd?3.
Main objective of this work was to obtain a complete description of the mechanical behaviour,including the failure space,for the aluminium foam FOAMINAL, provided by Fraunhofer-Institute for Applied Materials Research(IFAM)in Bremen(D).To obtain this result it a series of tests were conducted to characterize the material including building the necessary experimental equipment to perform the required tests.The tests that were de?ned for the analysis were the tensile and compression tests,the torsion test(purely deviatoric stress?eld),the hydrostatic test,in(pure hydrostatic stress),and a combination of hydrostatic and deviatoric stress which was termed hydro-compression.These were required to determine the failure surface.
Finally,it was important to demonstrate the effective-ness of the use of this foam for energy absorption.A series of tests on a composite structure made of the foam were inserted in a simple tubular structure.The tests on this structure were simple compression and bending,which are the most relevant loading modes during crash of vehicle structures.
This work has been performed within the VI Framework Programme European Project APROSYS(Advanced PROtection SYStems),whose main objective is increasing the safety of all road-users.Aluminium foams,in fact,can offer interesting solution to increase the energy absorption capability in vehicle components.
2.Aluminium foam characteristics
The aluminium foam considered here was manufactured by IFAM.The product emerging from IFAM process is a foam block obtained through a powder metallurgical process for preparing foamed metals.According to this process,commercial powders are mixed with small quantities of a powdered foaming agent by means of conventional techniques.The mixture is compacted to a semi-?nished product of low porosity by applying compac-tion techniques such as extrusion or co-extrusion.The result of the compaction process is a foamable semi-?nished product that can be worked into sheets,pro?les, etc.by applying conventional deformation techniques. During a?nal heat treatment at temperatures above the melting point of the corresponding alloy,the material expands and develops its highly porous,closed-cell structure.The density r can be controlled to be in the range from0.2to0.7g/cm3.The base material consists of aluminium–silicon alloy(Al–Si).Fig.1illustrates the geometry of a typical foam block.The coordinate system that was used is also given in Fig.1.Here,x denotes the major direction,whereas the transverse y direction is aligned with the width of the foam block;z is in the through-the-thickness,main expansion-in?uenced direction.
As it will be show in the following sections there is a certain degree of anisotropy due to the processing method and the gravity effect during solidi?cation.Therefore,it is convenient to assume a reference system for the foam samples related to the foaming process.Direction z (top–bottom)is the?rst foaming direction(for which,the boundary planes of the block are reached?rst during the foaming process,generally parallel to the vertical axis and, therefore,affected by gravity).Direction y is transverse (second foaming direction),while the third foaming direction,longitudinal,is the x direction.
Each block showed wide dispersion in the foam structure with large scatter in the cell size and shape,and the presence of some large holes randomly distributed.Table1 reports the main speci?cations of the blocks used in the test matrix.Fig.2shows the available blocks of foam to obtain test samples.
x z
y
longitudinal
t
o
p
-
b
o
t
t
o
m
(
e
x
p
a
n
s
i
o
n
)
transverse skin
z
y
D block
Fig.1.Block of foam.
L.Peroni et al./International Journal of Impact Engineering35(2008)644–658645
3.Cellular solids failure
In a material insensitive to the hydrostatic component of stress s hyd ,as homogeneous metals are usually considered,the failure limit in a deviatoric–hydrostatic space is a line parallel to the hydrostatic stress axis.When the deviatoric stress s dev reaches the yield line,yielding occurs.Therefore,for metals it is possible to inde?nitely increase the hydrostatic stress without yielding.If this hypothesis can be accepted,a single experimental test,excluding the hydrostatic component,gives the complete yield locus for this material.
The yield locus is different for foams [1–13],plastics,and other engineering materials.As shown qualitatively in Fig.3,there is an in?uence of the hydrostatic stress component [14,15].Failure models able to describe the
yield locus have been addressed in several works,for example Gibson and Zhang [1–4],Puso and Govindjee [5],and Fu Chang [6].
Gibson [1,4],Hanssen [7]for aluminium foams,and Zhang and Trianta?llou [2,3]use an elliptic failure surface in the deviatoric–hydrostatic space:s hyd àx 0a 2ts dev
b
2
p 1,
(4)
where s hyd and s dev are the hydrostatic and deviatoric components of the stress tensor previously de?ned,x 0is a parameter de?ning the centre of the ellipse,a and b are the size of the principal axis of this ellipse.
Deshpande and Fleck [8,9]and Christensen et al.[10]assume an elliptical failure criterion plus a cut-off tensile
Fig.2.Foam blocks from which the samples were obtained.
Table 1Block Dimensions (mm)For production of samples for tests A 41?41?100Compression tests on foam with skin B 45?45?100Compression tests on foam without skin C
+29?50Hopkinson bar tests on foam with and without skin
+25?50D
120?310?45
Compression tests on foam without skin Tensile tests on foam without skin
Hydro-compression and hydrostatic tests on foam without skin
Torsion tests on foam without skin E 41?41?500Bending tests,samples without skin F 45?45?500
Bending tests,samples with
skin
Fig.3.Typical yield curve for hypothetic foam in the deviatoric–hydro-static stress components space.Note :Differently from usual,the hydrostatic axis positive direction represents compression.
L.Peroni et al./International Journal of Impact Engineering 35(2008)644–658
646
stress criterion in the principal material axes system:
1ˉs11à
1
j s
11
j
s11t
s211
ˉs11j s11j
t
s212
es Y
12
T
p1,
s11
^s T
11
p1,e5Twhere s11and s12are the stress component in the12
coordinate system,ˉs T
11and s C
11
the tensile and compressive
failure stress respectively,s Y
12the yield stress,^s T
11
the tensile
rupture strength.
Gdoutos et https://www.doczj.com/doc/f61720445.html,ed an elliptical failure curve by applying Tsai-Wu theory[11]:
f1s1tf3s3tf11s2
1tf33s2
3
t2f13s1s3p1,(6)
where s1and s3are the principal stresses,f1,f3,f11,f33,and f13are experimentally obtained parameter of the failure criterion.
Gibson et al.[1,12]used another failure criterion for which the deviatoric stress components had a linear in?uence:
?s dev
s
pl
!
t0:81
r?
r a
s
hyd
s
pl
!2
p1.(7)
Therefore,a single experimental test is not enough to completely characterize the material behaviour.Since several parameters have to be determined to characterize the full failure space,at least an equivalent number of different experimental tests have to be performed.Conse-
quently,different tests are necessary in order to cover the widest possible range of combinations of deviatoric and hydrostatic stress components.The most relevant and feasible tests are:
–tension/compression test,s dev/s hyd?73;
–hydrostatic test,s hyd?àp/3,s dev?0,s dev/s hyd?0;–pure shear test,s hyd?0,s dev?t/O3,s dev/s hyd-N: 4-point asymmetric test,Iosipescu,or Arcan test
[11,13];
torsion test[10];
simple shear[4,18];
–generic biaxial/triaxial test,s dev/s hyd A[0,N]:
biaxial test[12];
hydro-compression and hydro-tension tests;and
combined tensile-compression/torsion[12,18],and
also hydrostatic[11].
The latter are free combinations of an independent hydrostatic stress component and a compression/tension independent load,which is achieved using a suitable test apparatus that is able to control both load components independently.The tests will be covered and discussed in detail in the following section.4.Experimental program
The complete characterization of an aluminium foam [7,9,10,16–18]was carried out in the Safety and Reliability Laboratory of Politecnico di Torino.This work was performed within the IP APROSYS.A qualitative over-view of the experimental program for the aluminum foam characterization is given in Fig.4.
https://www.doczj.com/doc/f61720445.html,pression tests
The quasi-static compression tests were carried out under a general purpose hydraulic testing machine (DARTEC HA100)controlled by a DARTEC9600 electronic unit,performing both test control and data acquisition.Measurements acquired within the9600unit are then transferred to a personal computer by means of dedicated software(DARTEC Toolkit96).Load was measured with a100kN,class A,strain-gage load cell directly mounted on the testing machine.Stroke was measured by means of a LVDT transducer directly connected to the hydraulic actuator.Therefore,engineering stress is obtained dividing the load values by the value of
Fig.4.Graphical overview of the experimental program.
L.Peroni et al./International Journal of Impact Engineering35(2008)644–658647
the transverse area.Transverse area is evaluated from the reported dimensional measurements.Average strain is evaluated by dividing the stroke by the initial measured length of the sample.Due to the manufacturing process,a rigid face-sheet,usually called skin,up to 1mm thick,is obtained.Skin can affect the foam behaviour:therefore,its effect was evaluated by removing it in some samples.Quasi-static experimental tests on 41mm ?41mm ?41mm specimens without skin were carried out on B-and D-series samples.The same tests on 41mm ?41mm ?41mm specimens with skin were carried out on A-series samples.A-series sample tests were aimed at check in?uence of skin on the foam behaviour,since foam with skin is used in composite structures.Since A,D and B series specimens were obtained from a block it was possible to de?ne the specimen principal directions with respect to the principal directions of the block (Fig.2).The experimental tests were carried out with different orienta-
tions of the specimen principal direction with respect to the testing direction.This is shown in the pictorial representa-tion of Fig.5.The grey shade relates to the value of the density of the sample extracted from the block.In each cell the loading direction is also shown (TB ?top–bottom,TR ?transverse,L ?longitudinal).
4.2.Tensile tests
The tensile tests were carried out under the same general purpose hydraulic testing machine used in the quasi-static compression https://www.doczj.com/doc/f61720445.html,pared to the very simple compres-sion tests,the problem of holding the sample arises in tension.After various attempt and different designs of the specimen,it was concluded that the best and simplest solution is to keep the simple constant section bar bonded to two plane parallel surfaces of the test ?xtures with a
Fig.5.Pictorial representation of the properties distribution in a D foam block.Each cell is a sample cut from the block (D1in this case):the plain number represents the density in kg/dm 3,while the bold number represents compression yield stress.The label inside the cells of the second and third rows is the sample identi?cation code:the ?rst and fourth rows are spare samples not used.The color also is related to the sample
density.
Fig.6.Tensile tests set-up:on the left the test machine with the tensile tests equipment,on the right a detail of a sample mounted on the tension grip and the transducer mounted for strain evaluation.
L.Peroni et al./International Journal of Impact Engineering 35(2008)644–658
648
suitable adhesive(hot-curing one-component epoxy),as shown in Fig.6.
Engineering stress is obtained by dividing the load values by the value of the unloaded cross sectional area.The transverse area is evaluated from the dimensional measure-ments reported.An additional LVDT was positioned directly on the specimen in order to measure the specimen elongation more accurately(Fig.6).Quasi-static experi-mental tests on41mm?41mm?100mm specimens with-out skin were carried out on the D-series specimens.Since the D-series specimens were obtained from a D block it was possible to de?ne the specimen principal directions with respect to the principal directions of the block.The experimental tests were carried out with the load applied in the y direction.
4.3.Torsion tests
Torsion tests were performed,in order to obtain a pure shear stress condition,with a torsion loading device which has been already used to test joints.The experimental testing device used for torsion tests is shown in Fig.7.The specimen is?xed to two circular plates.One plate,which can rotate around its axis,is constrained to the chassis of the testing device with a load cell that measures the torque applied to the specimen.The other plate is connected to a pneumatic rotary actuator which turns the plate and, consequently,loads the specimen in torsion.This device requires a particularly shaped specimen shown in the following Fig.8.It was obtained by machining a prismatic piece of D-series foam in a lathe.The axis of the cylindrical portion of the specimen is oriented in y direction of the D block.
An alternative solution for shear loading is to use the well known4-point asymmetric loading set-up.In this case, a pure shear loading is induced in the mid-section of a parallelepiped specimen.However,in this case also it is necessary to introduce a reduction in the mid section where failure is to be induced(grooves or V-notches,like in ASTM C1469-00).This is necessary to avoid bending failure near the supports.In fact,in4-point asymmetric loading only the mid section is loaded in pure shear, whereas every other transverse section is subjected both to the same value of shear and to a bending moment which linearly increases up to a maximum in the supports.If the mid section is not weakened enough,another section will
Fig.7.Experimental apparatus for torsion test:on the left the torsion test equipment,on the right a detail of the mounting of the specimen on the rotating loading
plates.
Fig.8.Specimen for torsion
tests.
Fig.9.Hydrostatic and hydro-compression tests area in the deviator-
ic–hydrostatic stress components space.
L.Peroni et al./International Journal of Impact Engineering35(2008)644–658649
fail due to a combination of shear stress and bending stress.However,the reduction required to insure failure in the mid-section will be generally too great if compared to the average cell dimensions.The results would not be signi?cant unless an exceedingly large specimen is used.4.4.Hydrostatic and hydro-compression tests
Hydrostatic compression tests were performed ?rst to assess the behaviour of the aluminium foam in a pure hydrostatic stress condition.Then,hydro-compression tests were carried out varying the ratio p ?s A /s R in order to obtain different s hyd –s dev combinations.As shown in Fig.9,by combining in different ways the axial stress s A and the radial stress s R it is possible to investigate the highlighted area of the s hyd –s dev plane.The limits of this area are the pure hydrostatic test (s A ?s R )and the pure compression test (s R ?0).
Performing hydrostatic and hydro-compression tests on metal foam is a challenging task.The foam specimen has to be completely separated from the ?uid used to load it;for this reason it was covered with a latex sheath in order to avoid seepage of the ?uid in the specimen.The cover has to be strong enough not to break during the test and,at the same time,it has to be very light and thin in order to avoid effects on the test results.After a series of unsuccessful trial,the best compromise to guarantee the integrity of the impermeable latex sheath without excessive stiffening was found covering the sample with a layer of ?exible PVC thermo retractable sheet.
Furthermore,in the hydro-compression tests it is necessary to control the axial and the radial pressure separately.For all these reasons a testing device (Fig.10)was designed and built expressly to perform these tests.The test chamber,containing the foam specimen,was ?lled with a ?uid (mixture of water and ethylene glycol)and mounted directly on the ?xtures of a general purpose hydraulic testing machine.
In the hydrostatic tests the specimen was placed on the vertical rod connected to the testing machine.This rod could move inside the test chamber in the axial direction changing the volume of the chamber and,consequently,the pressure of the ?uid inside the chamber,i.e.the pressure on the specimen.
In the hydro-compression tests the moving rod con-nected to the hydraulic testing machine,was pressing the specimen against a ?xed rod inside the chamber,thus generating the axial stress s A on the specimen.In parallel,a double-acting pneumatic cylinder was connected to the lateral surface of the test chamber.The rod of this piston can move inside the test chamber in the radial direction changing the volume of the chamber and,consequently,the pressure inside the chamber generating the radial stress s R on the specimen.
In both tests the electronic unit performed the test control and the data acquisition,while a PC equipped with
Fig.10.Hydrostatic and hydro-compression tests set-up:on the left the hydrostatic test equipment mounted on the loading machine,on the right schematics of the hydrostatic test equipment developed.
L.Peroni et al./International Journal of Impact Engineering 35(2008)644–658
650
a National Instruments acquisition board was used to acquire the load,stroke and pressure.In the hydro-compression tests the PC carried out the control of the radial pressure s R(pressure inside the test chamber)by moving the piston rod,whose displacement was measured through a potentiometer.The load applied by means of the rod connected to the testing machine was measured with a 100kN,class A,strain-gage load cell,while the stroke of the rod was measured by means of a LVDT transducer connected to the hydraulic actuator.The pressure inside the chamber was measured with a350bar strain-gauge pressure transducer applied to the chamber.
The specimens were cylinders cut from three D blocks, identi?ed as D2,D3and D4that were cut in seven sub-blocks each to obtain the samples.These prismatic square section sub-blocks were turned with a CNC lathe so that to get circular cylindrical specimens with a nominal diameter and height of41mm.Since in the quasi-static compression tests an anisotropic behaviour of the specimens was found, the specimens were machined in two different ways. In those specimens obtained from block D2the axial direction was parallel to the top–bottom direction of the block(Fig.2).On the contrary,in the ones obtained from blocks D3and D4the axial direction was parallel to the transversal direction of the block(Fig.2).
4.5.Split Hopkinson pressure bar(SHPB)tests
In order to evaluate the effect of strain-rate on foam behaviour,SHPB tests have been performed.The SHPB arrangement is the classical arrangement used for compres-sion tests[19].The striker bar(projectile)hits the input bar and generates a compressive stress pulse almost rectangu-lar.After the stress wave has travelled along the input bar, it reaches the specimen and loads it.A series of re?ection between the two faces of the specimen(the one in contact with the striker bar and the other one in contact with the output bar)occurs.After several(3–5)re?ections,the specimen is subjected to a homogeneous state of stress.
Being in equilibrium also with the output bar,there is a
stress wave generated into it.This stress wave(which is the
actual stress in the specimen)can be measured on the
surface of the output bar to evaluate the stress in the
specimen.It is easy to?nd that the stress and strain
generated by the re?ection of the wave in the input bar are
proportional to the strain-rate in the specimen.By
integrating this strain-rate signal in time,the strain history
in the specimen is obtained.Since foams absorb a large
quantity of energy and reach high levels of strain,the
energy of a single stress wave is not suf?cient.However,it
is possible to exploit the successive re?ection of the wave at
the end of the output bar to repeatedly load the specimen
MPSHPB(Multiple Pulses SHPB)[19].This allows to
reach very high levels of compression(up to50%
approximately).
During the test,the foam is kept in place with adhesive
band(not shown in Fig.11).The SPHB tests were
performed on C-series specimens with the load axis parallel
to the block x-axis,both on specimens with and without
skin and on composite specimens(aluminium tube6060 +28mm,thickness2mm with foam?ll inserted).Static and Taylor tests were also performed using C-series
samples(the Taylor test differs from the SHPB test for
the absence of the input bar:the striker bar directly impacts
the specimen,which is between the striker bar itself and the
output bar).
4.6.Dynamic impact tests
Tests have been performed under a drop tower testing
apparatus.The tower has a drop height of12m with a mass
range of40–120kg.Maximum available impact velocity is
about14m/s.The system is equipped with a three
piezoelectric220kN(bandwidth30kHz)load cells system
to measure the force and with an optoelectronic encoder
type speed transducer.The speed transducer,which is
Fig.11.Specimen for the HSPB tests in compression.
L.Peroni et al./International Journal of Impact Engineering35(2008)644–658651
essentially an incremental encoder,is also able to give a measure of the stroke during the test.Force and speed measurements are acquired with a dynamic analyzer having a maximum acquisition rate of 800?103samples/s.Then,by using collected data,it is possible to retrieve the global parameters,such as the mean impact force,the ef?ciency and the absorbed energy.
The sledge is guided during free fall by rollers on two rails.The impact plate is embedded in a concrete footing.The tests were performed on A,and B type specimens with the load axis parallel to the block x -axis,both on specimens with and without skin and on composite specimens (as described above).4.7.Bending tests
Foams used in real applications,mainly automotive,to improve energy absorption capability of crash beams and other structural components,are subjected not only to axial loads but,often,to bending also.Therefore,it is important to have information on the bending collapse of aluminium foams and structures ?lled with aluminium foams.Validation of material models can also pro?t from this kind of experimental tests [20].Many papers have addressed the coupling of foams with aluminium and steel columns,mainly under axial loading [7,21–26].It is expected that similar strengthening effects are obtained in bending.
Bending tests have been performed using a Zwick Z100universal-testing machine (100kN max load,1300mm stroke)and a dedicated support frame (Fig.12).The loading frame consists of a rigid bar with two sliding supports on which the specimen to be tested is placed.Each sliding support consists of a short shaft of 30mm diameter.The load is transferred to the column by a punch with a circular shape (50mm radius)in the contact zone.The circular shape of the punch,with large radius,avoids local
collapse and maintains a constant bending moment in the central section,between the two contact areas (see loading scheme in Fig.12,on the right).Normal force and displacement of the punch were measured with a 100kN load cell and a displacement transducer respectively.A PC controlled the machine operation and the force–displace-ment data acquisition.The cross-head speed was ?xed to 0.5mm/s while the distance between the two supports was 250mm.Bending tests have been performed on E and F type specimens with the neutral axis parallel to the block x -axis,both on specimens with and without skin and on composite specimens (6060aluminium tube 45?45thick-ness 2mm with foam ?ll).5.Results and analysis
The results obtained from the tests on the foam alone are reported in the Figs.from 13to 22.
Fig.13shows the results from uniaxial compression tests on D type specimens with the load applied along the z
Fig.12.Bending test.
Testing direction: top-bottom (z)
00
10203040500.2
0.4
0.6
0.8
1
Engineering strain (-)
S t r e s s
(M P a )
Fig.13.Uniaxial compression stress–strain results,on D samples of different density,loaded in top–bottom direction.
L.Peroni et al./International Journal of Impact Engineering 35(2008)644–658
652
direction (as explained by Fig.1).The results are reported in terms of the stress–strain curves during compression up to 90%engineering strain.First analysis of these experi-mental results can be carried out examining the character-istic points of each curve.The yield stress (Fig.13)was evaluated as the intersection of the two lines interpolating the ?rst part (elastic)and the second part (plateau)of the experimental stress-strain curve.In Fig.14the yield stress values are reported as a function of the density.In fact,the results are strongly dependent on the apparent density (average value within the volume of the sample which was always reported in kg/dm 3together with the specimen designation).Since there is a large scatter in size,wall thickness and shape of the cells,the apparent density varied considerably.Consequently,the test results are rather scattered.
Moreover,the presence of structural anisotropy in the specimens is evident in Fig.14a .The yield stress in compression is,in the top–bottom z direction,almost half the value measured along the other x and y directions.The in?uence of the presence of skin is also highlighted in Fig.14b .
Fig.15summarizes the results of tensile and torsion tests.For these test con?gurations,the specimen failure results from material fracture (Fig.16)at relatively small deformation (5–10%).Moreover,in tensile tests a clear non-linear material behaviour was observed even at very
low values of stress.This behaviour was observable in all the tests,and is probably due to the material non-homogeneity with weak points which progressively fail plastically even at very low values of the applied load.Some results of the hydrostatic compression tests are reported in Fig.17.As for other test types,there is a strong in?uence of density and a high scatter of the data.However,a general behaviour can be detected:the elastic modulus,the yield stress and the slope of the stress–strain curve after yielding,all increase with increasing density.Furthermore,the foam showed anisotropic behaviour,which can be detected by examining the deformed shapes of some specimens after the tests (Fig.18).In specimen H-D3-1the cross section lies in the plane identi?ed by the longitudinal x and the top–bottom direction z (see Fig.1for the reference axis system).Because,as noted above,along the top–bottom direction z the foam is weaker than along the longitudinal direction x ,the cross section (initially circular)of the specimen becomes elliptical after test (Fig.18,left).This did not occur in the H-D2-2specimen where the cross section lie in the plane de?ned by the longitudinal x and transverse direction y ,along which the material has approximately the same strength.Conse-quently,despite the slightly lower density,the yield stress of specimens H-D3-1is higher than H-D2-1and H-D2-2.The hydrostatic yield stress was evaluated the same way as the uniaxial compression tests.For the same density values,the yield stress is higher in the uniaxial compression test than in hydrostatic (this will be discussed in details later).In hydrostatic loading conditions,in fact,the cell walls are subjected to additional bending load.Instead,the densi?cation rate is greater for the hydrostatic loading condition since there is multiaxial load on the cells.
The hydro-compression tests were performed by apply-ing a proportional load,i.e.a ?xed ratio p ?s A /s R (Fig.19).In addition two hydro-compression static tests,on specimen H-D3-1and H-D3-2(reported in the previous section)were carried out simulating a hydrostatic test,i.e.with a ratio p ?1.Examining the results from these tests (stress versus axial and radial strain),different behaviour in
0246810
120
0.8
0.7
0.6
0.5
0.4
0.3
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Fig.15.Failure stress components vs.density in tensile and torsion tests on D samples.
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16Fig.14.Yield stress vs.density in uniaxial compression tests on D samples with different orientation.
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the axial and radial directions is noted.This behaviour is clearly shown in Fig.20,where the results of test performed on specimen H-D3-2are reported.Since this test was performed with the experimental device for the hydro-compression tests,it was possible to evaluate the axial and the radial characteristics separately.In Fig.20,it is possible to notice that,even if the load ratio p ?1was kept at a constant level during the test (equivalent points on the two curves have same ordinate but different abscissa,as suggested by the horizontal double tailed arrows),the
Fig.16.Tensile and torsion foam fracture.
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Fig.17.Hydrostatic compression tests:stress–strain curves,D
samples.
Fig.18.Cross section of H-D3-1(left)and H-D2-2(right)samples after the tests.
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axial and the radial yield stresses were quite different.This means that the ratio between the axial yield stress and the radial yield stress was different from the imposed ratio p .When yield occurs in the radial direction (at around 2MPa,radial strain starts increasing much more than axial strain)the material behaves linearly again in the axial direction.
This event is rather clear in the hydrostatic tests,while in the hydro-compression tests it was hardly observed.
For the SHPB tests,the maximum achievable strain with a single impact was lower than the maximum strain imposed in the quasi-static tests,since the total amount of available impact energy is limited and ?xed a priori.Multiple impacts can increase the total applied energy,and multiply the compression level,but for no more than four pulses.Fig.21shows the mechanical characteristics obtained from the SHPB test for two series of specimens with different densities.By analyzing the experimental data it can be observed that results are suf?ciently repeatable (considering results from samples with comparable density)and that the results dispersion is due to the variability of the material intrinsic properties,mainly the density.
The strain-rate achieved in the tests was about 8001/s.Due to the high variability in effective density,even with a reasonable number of repetitions of tests at the same nominal density,it was not easy to distinguish the effect of the different in?uencing factors.That is,it has not been possible to analyze specimens with the same density with all the different testing equipment.For this reason,the variation of the yield load as a function of the effective density of the samples,is reported in Fig.22.A linear relationship in a semi-logarithmic plane can describe the experimental results,with a suf?ciently narrow scatter band.
In order to evaluate the global foam behaviour in the different multiaxial load conditions,the results from all the tests may be represented on a s hyd –s dev diagram,as in Fig.3.Fig.23compiles all the experimental results,in terms of the failure load in tensile and torsion tests,and of the yield load in compression (uniaxial and hydrostatic).The scatter due to density variations and anisotropy make any clear data interpretation dif?cult.
Instead,the results must be analyzed taking into account the density variation and the material orientation,as shown in Fig.24.The data corresponding to the various
A x i a l a n d r a d i a l s t r e s s (M P a )
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Fig.20.Hydrostatic test (p ?1)on specimen
H-D3-2.
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Fig.21.SHPB compression test results.
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Fig.19.Hydro-compression tests results:variation of the yield stress with density.
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Fig.22.Yield stress vs.foam density and deformation energy vs.foam density in different uniaxial compression tests.
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loading conditions were obtained by interpolating the experimental results at three different density values (0.50,0.55,0.60kg/dm 3).A second classi?cation is based on the sample axis (axis refers to the main loading direction).There are two cases:(1)the sample axis is along the major strength directions (that is,the x and y directions);(2)the sample axis is along the minor strength direction (that is,the z direction or top–bottom direction).
The foam behaviour seems to be described by an elliptic limit curve,with a shift in the deviatoric.By applying the ?t with Eq.(4)[1–4,7],the failure limit curves for the three densities,and for the two sample axes are obtained as in Fig.24.The shear test results do not match the two families of curves,since they do not belong to either case.In shear stress loading by torsion the principal directions are at 451with respect to the sample axis,therefore,the effect of loading in the two directions is combined.
For the tests performed on the composite structures made of the aluminium foam ?lled extrusions,the results are in agreement with those obtained on the cellular solid material only.In compression,the stress in the foam continues to be mostly compression type (the presence of the constraint imposed by the tube add triaxiality to the state of stress),with absence of fracture.This leads to very high energy absorption,much higher than the sum of the energy that can be potentially accumulated by the two sub-elements (foam and tube),as it is evident in Fig.25.This is essentially due to the interaction of the tube with the foam,which causes a variation of the tube collapse mode.The behaviour is similar in the dynamic tests (Fig.26):due to the absence of in?uence of the strain-rate on the aluminium foam behaviour and on the tube aluminium alloy,the results of the dynamic tests are substantially in agreement with those of the static tests.Only a slight increase of the collapse loads due to inertia effects is present.
In the case of ?exure (Fig.27),tensile stresses produce fracture in the tensile zone.Consequently,the behaviour of the foam alone (with or without skin)is in agreement with the results of tensile tests,which leads to very low energy
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2
3
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D e v i a t o r i c s t r e s s (M P a
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Fig.24.Failure loci of tested aluminum foam,considering the effect of the density and material orientation.The two sets of three curves correspond to the three characteristic foam densities of 0.50,0.55,and 0.60kg/dm 3,as indicated in the legend,and for the two main loading directions parallel to y and z ,as in the legend.
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Fig.23.Failure locus of tested aluminium foam.
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Fig.26.Dynamic compression load–displacement tests results on composite structure.
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absorption.The combination of the foam with the tube allows having a composite structure with high energetic absorption and collapse load,if compared with the basis elements (Fig.27).The foam presence,in fact,produces a substantial change in the tube collapse mechanism.
Even if the foam fractures,the effect of internal constraint of the tube gives some bene?ts for the energetic absorption,avoiding the formation of the well known bending collapse mechanism (with consequent decrease of the resistant load).However,the new collapse mechanism increases the tensile stresses in the tube walls:with higher rotations.This causes the fracture of the tube,with consequent sudden decrease of the load and of the capacity of further energy absorption.This situation is made worse by the reduced fracture deformations of the aluminium alloys for extrusion.6.Conclusions
The full multiaxial characterization of a cellular metallic material,which required a series of tests in tension,compression,torsion,and hydrostatic loading,proved to be a challenging task.Especially,in tests with hydrostatic component,the isolation of the specimen from the ?uid used to load it was particularly dif?cult.In many tests,the cover used to protect the specimen from seepage of the ?uid failed and the ?uid penetrated into the specimen causing an early end of the test.For this reason,large body of experimental work was carried out in order to set up the testing devices and procedure.To check whether there the strain-rate in?uenced the material behaviour,tests in a SHPB apparatus were also performed.Finally,since the material is meant to be used in crash applications to increase energy absorption of vehicle structures,some tests of a simple composite structure made of an aluminium tube ?lled by the aluminium foam were carried out.Both in axial compression and in bending,the contribution of the foam is quite important,more than the pure addition of
the contributions of the two materials to the absorbed energy.
A primary issue in the analysis of such type of material is the large density scatter:this caused many serious problems in the evaluations of the mechanical properties and of the effects of density.Moreover,it will be a serious problem in the real applications.A second aspect that has been pointed out is the material anisotropy:a weaker orienta-tion has been identi?ed along the main foaming direction.This was well evident in the hydrostatic tests,where a circular cylindrical specimen deforms into an elliptical cylinder,and in the hydro-compression tests,where,if simulating an hydrostatic state of stress with three equal values of stress acting along three orthogonal directions,yield collapse occurs at different strain levels in the different directions.
Tensile failure was investigated by means of tensile and shear (torsion)tests.In both cases there is brittle fracture after yield.Stiffness and yield strength in tension are comparable with the values observed in compression.By comparing tensile and shear test results,it comes that the value of the deviatoric stress at failure does not change signi?cantly.Therefore,a positive hydrostatic stress seems not to affect the failure of the foam.
From the results of these tests it has been possible to obtain the yield locus of the aluminium foam in the deviatoric–hydrostatic stress components space.One of the most important variation factors is the density,which,unfortunately is not suf?ciently constant in the material sample.The density variation is,therefore,to be taken into account in the design of components with aluminium foam in it.
Finally,a series of dynamic tests were performed on the aluminium foam examined.The data obtained by dynamic tests do not differ from the trend of static tests results,taking into account the density variations.It may be stated that the analyzed metallic foam does not present any signi?cant dependence on the strain-rate.
However,even if the analysis is not extended to a complete model of the foam behaviour in all the possible loading con?gurations,the results presented here and the model describing the yield locus in the deviatoric–hydrostatic plane,are a sound basis for the description of this material for design in structural applications.Acknowledgements
This work was performed within the Subproject 7‘‘Virtual Testing’’of the FP6European Project APROSYS.The ?nancial support of the European Commission by means of the APROSYS project and Dirk Lehmhus of Fraunhofer-Institute for Applied Materials Research (IFAM,Germany)are gratefully acknowledged.Thanks also to the co-ordinator of the subproject,Dr.Kambiz Kayvantash of Mecalog (France)and to the workpackage 7.1leader Mr.Roberto Puppini of Fiat Research Center (Italy).
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Fig.27.Bending tests results.
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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
The way 的用法 Ⅰ常见用法： 1)the way+ that 2)the way + in which（最为正式的用法） 3)the way + 省略（最为自然的用法） 举例：I like the way in which he talks. I like the way that he talks. I like the way he talks. Ⅱ习惯用法： 在当代美国英语中，the way用作为副词的对格，“the way+ 从句”实际上相当于一个状语从句来修饰整个句子。 1)The way =as I am talking to you just the way I’d talk to my own child. He did not do it the way his friends did. Most fruits are naturally sweet and we can eat them just the way they are—all we have to do is to clean and peel them. 2）The way= according to the way/ judging from the way The way you answer the question, you are an excellent student. The way most people look at you, you’d think trash man is a monster. 3）The way =how/ how much No one can imagine the way he missed her. 4）The way =because
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
The way的用法及其含义（二） 二、the way在句中的语法作用 the way在句中可以作主语、宾语或表语： 1.作主语 The way you are doing it is completely crazy.你这个干法简直发疯。 The way she puts on that accent really irritates me. 她故意操那种口音的样子实在令我恼火。The way she behaved towards him was utterly ruthless. 她对待他真是无情至极。 Words are important, but the way a person stands, folds his or her arms or moves his or her hands can also give us information about his or her feelings. 言语固然重要,但人的站姿,抱臂的方式和手势也回告诉我们他(她)的情感。 2.作宾语 I hate the way she stared at me.我讨厌她盯我看的样子。 We like the way that her hair hangs down.我们喜欢她的头发笔直地垂下来。 You could tell she was foreign by the way she was dressed. 从她的穿著就可以看出她是外国人。 She could not hide her amusement at the way he was dancing. 她见他跳舞的姿势，忍俊不禁。 3.作表语 This is the way the accident happened.这就是事故如何发生的。 Believe it or not, that's the way it is. 信不信由你, 反正事情就是这样。 That's the way I look at it, too. 我也是这么想。 That was the way minority nationalities were treated in old China. 那就是少数民族在旧中
定冠词the的用法： 定冠词the与指示代词this ,that同源,有“那(这)个”的意思,但较弱,可以和一个名词连用,来表示某个或某些特定的人或东西. (1)特指双方都明白的人或物 Take the medicine.把药吃了. (2)上文提到过的人或事 He bought a house.他买了幢房子. I've been to the house.我去过那幢房子. (3)指世界上独一无二的事物 the sun ,the sky ,the moon, the earth (4)单数名词连用表示一类事物 the dollar 美元 the fox 狐狸 或与形容词或分词连用,表示一类人 the rich 富人 the living 生者 (5)用在序数词和形容词最高级,及形容词等前面 Where do you live?你住在哪? I live on the second floor.我住在二楼. That's the very thing I've been looking for.那正是我要找的东西. (6)与复数名词连用,指整个群体 They are the teachers of this school.(指全体教师) They are teachers of this school.(指部分教师) (7)表示所有,相当于物主代词,用在表示身体部位的名词前 She caught me by the arm.她抓住了我的手臂. (8)用在某些有普通名词构成的国家名称,机关团体,阶级等专有名词前 the People's Republic of China 中华人民共和国 the United States 美国 (9)用在表示乐器的名词前 She plays the piano.她会弹钢琴. (10)用在姓氏的复数名词之前,表示一家人 the Greens 格林一家人(或格林夫妇) (11)用在惯用语中 in the day, in the morning... the day before yesterday, the next morning... in the sky... in the dark... in the end... on the whole, by the way...
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。
“tｈｅwａｙ+从句”结构的意义及用法 首先让我们来看下面这个句子: Ｒead the foｌloｗｉnｇpassagｅａnd talkａbout ｉt wi ｔh your classmaｔes．Try tｏｔeｌl whaｔyｏu thiｎk ｏf Tom aｎd ｏｆｔhe ｗay the chiｌｄrenｔrｅated ｈim. 在这个句子中，ｔhe waｙ是先行词,后面是省略了关系副词that或in whｉch的定语从句。 下面我们将叙述“the ｗaｙ+从句”结构的用法。 1.tｈe wａy之后，引导定语从句的关系词是tｈat而不是hoｗ,因此，<<现代英语惯用法词典＞＞中所给出的下面两个句子是错误的：Ｔhｉs is ｔｈeｗayｈowｉtｈａppened. This is the way how he ａlwａｙs treats me. 2．在正式语体中,thaｔ可被in which所代替;在非正式语体中，ｔhat则往往省略。由此我们得到theｗay后接定语从句时的三种模式：1) tｈe ｗaｙ＋ｔhａt-从句２）the way +ｉn whiｃh－从句3) the ｗay +从句 例如：Ｔｈe way(in whiｃh ，thａt) ｔhｅｓｅｃomｒade ｓloｏｋａｔｐrobｌems is wrong．这些同志看问题的方法
不对。 Ｔｈｅｗａy(that ,ｉn ｗhiｃh)yoｕ’ｒe doinｇit is comple ｔeｌy crａzy.你这么个干法,简直发疯。 Wｅａdmiｒｅd him for thｅｗay ｉｎｗhｉch he fａｃeｓdiｆficultieｓ． Waｌlａｃe ａｎd Ｄarwiｎｇreed ｏn the way ｉｎwhi ｃh ｄｉfｆｅrｅnt forms ｏf life had ｂegｕn.华莱士和达尔文对不同类型的生物是如何起源的持相同的观点。 Thｉs is ｔｈe ｗaｙ（tｈａｔ) hｅdｉd it. I lｉkeｄｔhe waｙ(ｔhat) ｓｈeｏｒganized ｔhe ｍeetｉng． 3.theｗay(tｈat)有时可以与hｏw(作“如何”解）通用。例如： That’s tｈe ｗaｙ(tｈaｔ) shｅspoke. = Tｈat’s how shｅspoke.
表示“方式”、“方法”，注意以下用法： 1.表示用某种方法或按某种方式，通常用介词in(此介词有时可省略)。如： Do it (in) your own way. 按你自己的方法做吧。 Please do not talk (in) that way. 请不要那样说。 2.表示做某事的方式或方法，其后可接不定式或of doing sth。 如： It’s the best way of studying [to study] English. 这是学习英语的最好方法。 There are different ways to do [of doing] it. 做这事有不同的办法。 3.其后通常可直接跟一个定语从句(不用任何引导词)，也可跟由that 或in which 引导的定语从句，但是其后的从句不能由how 来引导。如： 我不喜欢他说话的态度。 正：I don’t like the way he spoke. 正：I don’t like the way that he spoke. 正：I don’t like the way in which he spoke. 误：I don’t like the way how he spoke. 4.注意以下各句the way 的用法： That’s the way (=how) he spoke. 那就是他说话的方式。 Nobody else loves you the way(=as) I do. 没有人像我这样爱你。 The way (=According as) you are studying now, you won’tmake much progress. 根据你现在学习情况来看，你不会有多大的进步。 2007年陕西省高考英语中有这样一道单项填空题： ——I think he is taking an active part insocial work. ——I agree with you_____. A、in a way B、on the way C、by the way D、in the way 此题答案选A。要想弄清为什么选A，而不选其他几项，则要弄清选项中含way的四个短语的不同意义和用法，下面我们就对此作一归纳和小结。 一、in a way的用法 表示：在一定程度上，从某方面说。如： In a way he was right.在某种程度上他是对的。注：in a way也可说成in one way。 二、on the way的用法 1、表示：即将来(去)，就要来(去)。如： Spring is on the way.春天快到了。 I'd better be on my way soon.我最好还是快点儿走。 Radio forecasts said a sixth-grade wind was on the way.无线电预报说将有六级大风。 2、表示：在路上，在行进中。如： He stopped for breakfast on the way.他中途停下吃早点。 We had some good laughs on the way.我们在路上好好笑了一阵子。 3、表示：(婴儿)尚未出生。如： She has two children with another one on the way.她有两个孩子，现在还怀着一个。 She's got five children，and another one is on the way.她已经有5个孩子了，另一个又快生了。 三、by the way的用法
女生唱的歌曲欢快甜美 美妙的歌曲能令我们陶醉其中而无法自拨，最激烈的歌曲能令我们的身体不由自主的跟着手舞足蹈起来，下面是小编整理的欢快甜美的歌曲的内容，希望能够帮到您。 欢快甜美的歌曲 1. Talking - 2. 羽毛- 劲歌金曲 3. 为你- 黑龙 4. 我的小时候- 罗艺达 5. 听说爱情回来过 6. 那个男人 7. 夫妻观灯_韩再芬、李迎春- 中国民歌宝典二 8. 往生- 镀飞爱在阳光空气中- 区瑞强- 音乐合辑 9. 说中国- 班- 华语群星 10. 第十八封信- Kent王健 11. 那一夜你喝了酒- 傅薇 12. 最近比较烦- 周华健/李宗盛/品冠- 滚石群星 13. 告白- 张娜拉 14. Talking VIII - 15. my love - 网友精选曲 16. 音乐人民- 音乐合辑 17. 深深深深- 徐誉滕 18. Honkytonk U - Toby Keith 19. 征服- 阿强 20. 我总会感动你- 沙宝亮欢快甜美的歌曲 1. 一千步的距离- 高桐 2. fleeing star - 音乐合辑 3. My Life - 李威杰 4. 小妹听我说- 金久哲 5. 上海滩- 梁玉嵘- 华语群星 6. 爱我多爱一些- 黎姿 7. 恋人未满- 8. 玛奇朵飘浮- 音乐听吧 9. 風- 音乐听吧 10. 七月- 小鸣 11. 滚滚红尘- 罗大佑 12. 张震岳—想要- 华语群星 13. 有梦有朋友- 14. 童年- 拜尔娜 15. 洪湖水，浪打浪- 宋祖英 16. 只爱到一半- 魏晨 17. 风雨人生路- 何静 18. 居家男人- 回音哥如果当时- 许嵩 19. 那个男人的谎言Tae In - 非主流音乐
The way的用法及其含义（一） 有这样一个句子：In 1770 the room was completed the way she wanted. 1770年，这间琥珀屋按照她的要求完成了。 the way在句中的语法作用是什么？其意义如何？在阅读时，学生经常会碰到一些含有the way 的句子，如：No one knows the way he invented the machine. He did not do the experiment the way his teacher told him.等等。他们对the way 的用法和含义比较模糊。在这几个句子中，the way之后的部分都是定语从句。第一句的意思是，“没人知道他是怎样发明这台机器的。”the way的意思相当于how；第二句的意思是，“他没有按照老师说的那样做实验。”the way 的意思相当于as。在In 1770 the room was completed the way she wanted.这句话中，the way也是as的含义。随着现代英语的发展，the way的用法已越来越普遍了。下面，我们从the way的语法作用和意义等方面做一考查和分析： 一、the way作先行词，后接定语从句 以下3种表达都是正确的。例如：“我喜欢她笑的样子。” 1. the way+ in which +从句 I like the way in which she smiles. 2. the way+ that +从句 I like the way that she smiles. 3. the way + 从句(省略了in which或that) I like the way she smiles. 又如：“火灾如何发生的，有好几种说法。” 1. There were several theories about the way in which the fire started. 2. There were several theories about the way that the fire started.
【适合女生唱的各种难度的歌】以后点歌的时候记得挑战一下自己（哈哈，今天心情高兴，在微博整理下的小东西和大家分享） 1.我不知道--唐笑（特别喜欢的一首歌） 2.那个--文筱芮（特别伤的歌，真的可以听到心里去） 3.一半--丁当（喜欢喜欢，但没能力唱） 4.指望--郁可唯（本来不喜欢她，但她唱歌挺有水平） 5.路人--江美琪（推荐，好听又挺好唱的） 6.过敏--杨丞琳（听听就知道了） 7.大女人--张亚飞（没什么名气的超级女生，这歌挺棒的） 8.一个人的星光--许静岚（绿光森林的主题曲） 9.不要说爱我--许紫涵（高潮真的挺好听，我爱单曲循环，但这歌还没腻） 10.为你我受冷风吹--林忆莲（没那么简单，都是很喜欢的老歌，偶尔听听老歌感觉特别好） 11.一秒也好--卓文萱（她的（爱我好吗）也不错，最近挺喜欢她的歌） 12.你在哪里--张婧（不被太多人知道的歌手） 13.你的背包--莫艳琳（在校内看到一个女孩唱的，觉得挺好听的） 14.原来爱情那么难--泳儿（好听好听，没什么难度，就是在ktv不太好找） 15.在你眼里--同恩（也是到副歌特别吸引人的一首）
16.很久很久以后--梁文音（爱她的歌，她的很多歌都特别好听） 17.知道我们不会有结果--金莎（听着特别有感觉，那些喜欢听悲伤歌的都是因为这种感觉吧） 18.指尖的星光--钟汶（不太好唱的，我就只有听的份了） 19.放不下--龚诗嘉（挺简单的一首，调调挺平的，她的（远远在一起）也不错） 20.灰色的彩虹--范玮琪 21.现在才明白--萧贺硕（不被太多人知道的歌手，有些歌真的很好听，只是需要慢慢挖掘） 22.终点--关心妍（这首歌大多都听过，自己感觉吧） 23.遇到--王蓝茵（旋律让人感觉特舒服的，很爱的一首） 24.一个人--蔡依（她的毅力不是一般人能做到的） 25.婴儿--陈倩倩（这首歌真的凄凉到有点甚人的感觉。“喜欢一个人的心情”--江语晨，因为这歌的词）26.那又怎么样呢--张玉华（我爱听音乐，但一定要是伤感的，虽然不会听到泪流满面，但是那种感觉真的很好） 27.还爱你--景甜（像这样好听，又不被大家熟悉的歌还有很多吧）
way 的用法 【语境展示】 1. Now I’ll show you how to do the experiment in a different way. 下面我来演示如何用一种不同的方法做这个实验。 2. The teacher had a strange way to make his classes lively and interesting. 这位老师有种奇怪的办法让他的课生动有趣。 3. Can you tell me the best way of working out this problem? 你能告诉我算出这道题的最好方法吗？ 4. I don’t know the way (that / in which) he helped her out. 我不知道他用什么方法帮助她摆脱困境的。 5. The way (that / which) he talked about to solve the problem was difficult to understand. 他所谈到的解决这个问题的方法难以理解。 6. I don’t like the way that / which is being widely used for saving water. 我不喜欢这种正在被广泛使用的节水方法。 7. They did not do it the way we do now. 他们以前的做法和我们现在不一样。 【归纳总结】 ●way作“方法，方式”讲时，如表示“以……方式”，前面常加介词in。如例1； ●way作“方法，方式”讲时，其后可接不定式to do sth.，也可接of doing sth. 作定语，表示做某事的方法。如例2，例3；
分享适合女生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
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 87、那片海----韩红 88、美丽心情----RURU
t h e-w a y-的用法
The way 的用法 "the way+从句"结构在英语教科书中出现的频率较高, the way 是先行词, 其后是定语从句.它有三种表达形式:1) the way+that 2)the way+ in which 3)the way + 从句(省略了that或in which),在通常情况下, 用in which 引导的定语从句最为正式,用that的次之,而省略了关系代词that 或 in which 的, 反而显得更自然,最为常用.如下面三句话所示,其意义相同. I like the way in which he talks. I like the way that he talks. I like the way he talks. 一.在当代美国英语中,the way用作为副词的对格,"the way+从句"实际上相当于一个状语从句来修饰全句. the way=as 1)I'm talking to you just the way I'd talk to a boy of my own. 我和你说话就象和自己孩子说话一样. 2)He did not do it the way his friend did. 他没有象他朋友那样去做此事. 3)Most fruits are naturally sweet and we can eat them just the way they are ----all we have to do is clean or peel them . 大部分水果天然甜润,可以直接食用,我们只需要把他们清洗一下或去皮.
婴儿——陈倩倩 这首歌真的凄凉到有点儿甚人的感觉。“喜欢一个人的心情”——江语晨，因为这歌的词。 那又怎么样呢——张玉华 我爱听音乐，但一定要是伤感的，虽然不会听到泪流满面，但是那种感觉真的很好 还爱你——景甜 你可以爱我很久吗——游艾迪 夜夜夜夜——原唱齐秦 爱一直存在——梁文音 有人想找男生唱的，真不常听男生的歌，不过有几首觉得挺不错的。 初雪的忧伤——赵子浩 爱你，离开你——南拳妈妈 说谎——林宥嘉 三人游、爱爱爱——方大同 分开以后——唐禹哲 突然好想你——五月天 还是男生的， 寂寞的季节、暗恋——陶喆 情歌两三首——郭顶 掌纹——曹格 需要人陪——王力宏 王妃——箫敬腾（除了这首，其他几首都是比较安静抒情的。） 挥之不去——殷悦 别再哭了——罗忆诗 前段时间特别喜欢这首歌，听的快吐了，真的挺好听。 热气球——黄淑惠 很特别，超级好听，强烈推荐。 你是爱我的——张惠妹 她的嗓音让我着迷，超级喜欢。 问——粱静茹 老歌了，不过很喜欢。
忽略——萧萧 握不住的他，看到萧萧还是会第一个想起这首。 趁早——张惠妹 她有点儿沙哑的声音让我着迷。 幸运草——丁当 早点儿的歌了，喜欢丁当。 哭了——范晓萱 越听越喜欢，。 氧气——范晓萱 小时候喜欢听她的歌，不过随着年龄的增长，喜欢的类型也变了。 温柔的慈悲——阿桑 喜欢她的歌，只是她的声音不能再更新了。 礼物——刘力扬 罗美玲的也还好。。 洋葱——丁当杨宗纬（两个不一样的感觉） 挺难的唱不好，不过喜欢听。 眼泪知道——温岚 喜欢，唱出来特别有激情哈。
类似爱情——萧亚轩 不难又有感觉。 第三者——梁静茹 还好，喜欢这首歌的歌词。 心墙——郭静 “我不想忘记你”，“不药而愈”，“每一天都不同”，都好听喜欢她的歌。 我知道你很难过——蔡依林 唱起来有感觉也不难唱，推荐。 夏伤——SARA 感觉很特别，喜欢。 那天——蓝又时 喜欢她的歌，她的调调，强烈推荐。“秘密”也不错。 礼物——罗美玲 好听有感觉，不过不太好唱。 我比想象中爱你——JS 老歌了一直很喜欢，唱起来有感觉。
魅力四射的独唱舞台 ——甜美纯净的女声独唱 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。
way的用法总结大全 way的用法你知道多少，今天给大家带来way的用法，希望能够帮助到大家，下面就和大家分享，来欣赏一下吧。 way的用法总结大全 way的意思 n. 道路,方法,方向,某方面 adv. 远远地，大大地 way用法 way可以用作名词 way的基本意思是“路,道,街,径”,一般用来指具体的“路,道路”,也可指通向某地的“方向”“路线”或做某事所采用的手段,即“方式,方法”。way还可指“习俗,作风”“距离”“附近,周围”“某方面”等。 way作“方法,方式,手段”解时,前面常加介词in。如果way前有this, that等限定词,介词可省略,但如果放在句首,介词则不可省略。
way作“方式,方法”解时,其后可接of v -ing或to- v 作定语,也可接定语从句,引导从句的关系代词或关系副词常可省略。 way用作名词的用法例句 I am on my way to the grocery store.我正在去杂货店的路上。 We lost the way in the dark.我们在黑夜中迷路了。 He asked me the way to London.他问我去伦敦的路。 way可以用作副词 way用作副词时意思是“远远地,大大地”,通常指在程度或距离上有一定的差距。 way back表示“很久以前”。 way用作副词的用法例句 It seems like Im always way too busy with work.我工作总是太忙了。 His ideas were way ahead of his time.他的思想远远超越了他那个时代。 She finished the race way ahead of the other runners.她第一个跑到终点,远远领先于其他选手。 way用法例句
适合女生唱的100首好听的歌 1、偏爱----张芸京 2、阴天----莫文蔚味道很难把握 3、眼泪----范晓萱还好，张学友版本适合男生 4、我要我们在一起---范晓萱A段超级难唱的，拍子和口气都不好抓 5、无底洞----蔡健雅听起来简单，唱起来很难——这首是典型的例子 6、呼吸----蔡健雅 7、原点----蔡健雅&孙燕姿到哪里找两个好听的女中音呢？ 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----梁咏琪为什么没有洗脸？剪发？胆小鬼？ 15、蓝天----张惠妹 16、记得----张惠妹 17、简爱----张惠妹是剪爱吧？ 18、趁早----张惠妹男生可以试试张宇的版本 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----范玮琪范范的歌这么多啊。。。 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----辛晓琪我一直在找这个歌曲的粤语版，却找不到
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----那英在KTV点这个歌曲的MTV不是会很尴尬吗？ 39、梦醒了----那英 40、出卖----那英 41、梦一场----那英 42、愿赌服输----那英没有征服？也许是太大众了吧。 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----萧亚轩还记得她第一张专籍里面最喜欢那首《没有人》 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