• <tr id="yyy80"></tr>
  • <sup id="yyy80"></sup>
  • <tfoot id="yyy80"><noscript id="yyy80"></noscript></tfoot>
  • 99热精品在线国产_美女午夜性视频免费_国产精品国产高清国产av_av欧美777_自拍偷自拍亚洲精品老妇_亚洲熟女精品中文字幕_www日本黄色视频网_国产精品野战在线观看 ?

    Higher-Order Corrections to Earth’s Ionosphere Shocks?

    2017-05-18 05:56:55AbdelwahedandElShewyPlasmaTechnologyandMaterialScienceUnitPTMSUPhysicsDepartmentCollegeofScienceandHumanitarianStudiesPrinceSattambinAbdulazizUniversityAlkharjKSA
    Communications in Theoretical Physics 2017年1期

    H.G.Abdelwahedand E.K.El-ShewyPlasma Technology and Material Science Unit(PTMSU),Physics Department,College of Science and Humanitarian Studies,Prince Sattam bin Abdulaziz University,Alkharj,KSA

    2Theoretical Physics Group,Physics Department,Faculty of Science,Mansoura University,Mansoura,Egypt

    1 Introduction

    Research on ion-acoustic waves(IAWs)in ion pair plasmas has gained considerable amount of momentum over the last few years.[1?2]Positive-negative ion have been observed in many astrophysical environments.[3]More speci fically,Negative ions are present in D-region altitudes of the ionosphere of Earth in coexistence with electrons as they are formed primarily by electron added to electronegative species.[4]In last few years,ion solitary waves in ion-pair plasmas investigated both numerically and experimentally.[5?6]In past,the nonthermal particles observed in many space environments.[7?9]However,several theoretical studies on nonlinear waves show that,electrons and ions non-thermal distributions are convenient in analyzing observation data in space plasma.[7?12]Cairns etal.[9]discussed the nonthermal electron e ff ect on the ion acoustic wave existence.Elwakil etal.[2]inspected ion acoustic modulation instability characteristics in plasma having nonthermal electronsand positive-negative ions.It is reported that,the instability conditions a ff ected by nonthermal electron parameter in D and F regions in Earth’s ionosphere.Gill etal.[13]investigated rarefactive and compressive soliton properties in two polarized ions plasma.Recently,nonthermality e ff ect of positron-electron have been examined on the properties of improved compressiverarefactive solitons generated in warm ion plasma.[14]On the other hand,there are many theoretical methods for studying nonlinear properties in plasma physics.Reductive perturbation analysis(RPT)aim to study the propagation of small wave amplitude.[15]As the wave amplitude enlarge,the solitary pro fi le sidetrack from the nonlinear equation.In order to beat this deviation,the amplitude modulation of electrostatic nonlinear waves has been studied by many investigators.[16?19]Kalejahi etal.[19]discussed the higher order nonlinear e ff ects in a relativistic plasma.Abdelwahed and El-Shewy[16]improved the soliton shape of solitary wave directly by using algebraic analysis for solving the field equations.Chatterjee etal.[17]examined the region of solitary wave existence in nonthermal ions plasma.They discussed the e ff ect of nonthermal ions and electron density on the properties of obtained dressed form.Accordingly,to improve the description of experimental data,the e ff ect of fl uctuation of charge of dusty plasma on the dressed nonlinear soliton waves has been investigated.[20]On the other hand,dusty size e ff ect on the dressed soliton like wave amplitude and energy have been discussed in dust plasma containing dust grains and nonthermal ions.[21]Physically,some phenomenon like kinematic viscosity,collisions between plasma components and Landau damping are responsible for shocks formation in Earth ionosphere.[22?24]The shock wave existence and propagation have been investigated experimentally and theoretically.[25?31]Cairns etal.[32]investigated laminar ion shocks to explain observations on ion acceleration laser plasmas.Abdelwahed[33]obtained the higher order dissipation in terms of Burger-type equation to modulate the broadband auroral electrostatic shock noise.From theoretical point of view,Kadomtsev–Petviashvili–Burgers(KPB)equation has been derived by Hussain etal.[34]They discussed the di ff raction and dissipation e ff ects on the shock wave structures in epi plasma with kappa distributed positrons and electrons.More speci fically,the obliqueness of solitary shocks in a magnetized viscous plasma have been studied.[35]Abdelwahed and el-Shewy[36]studied the nonlinear features of rational and double layer ion acoustic solitary solutions.Furthermore,Masood and Rizvi[37]investigated the viscosity e ff ect of negative and positive ions in dissipative plasma medium in a planar geometry.Also,kinematic viscosity e ff ect on formation of shock waves in asymmetric pair ion plasmas has been examined.[38]It was noted that,kinematic viscosity enhances the amplitude of shock pro fi le.In this study,the higher-order acoustic shock modulation in plasmas with negative-positive ions and nonthermal electrons have been considered.In Sec.2,the equations of the system is presented,and higher-order Burgers equation is derived in Sec.3.In Sec.4,the solutions of the higherorder Burgers-equation are presented.Finally,the results and discussion are recapitulated in Sec.5.

    2 Basic Equations

    A system of three collisionless unmagnetized plasmas components having viscous fl uid of positive(+)and negative(?)ion and nonthermally electron distribution.The normalized equations are given by:

    neis the electrons density obey nonthermally distributed.[9]

    where δ is the electron nonthermality parameter andμ=ne0/n+0is the unperturbed electron to positive ion ratio.In Eqs.(1)–(5),n+(n?)is positive(negative)ionic density(normalized by n+0(n?0),u+(u?)is positive(negative)ion fl uid velocity normalized by the ion sound speed

    and ? is electrostatic wave potential(normalized by KBTe/eZ+).x(t)is space(time)coordinate,x is normalized to Debye length of hot electron

    t normalized by inverse of plasma frequency of cold electron

    where KBis the Boltzmann constant.Teis the electron temperature,ν =n?0/n+0,and the Q(mass ratio)=m+/m?,where m+and m?are positive and negative ion masses,respectively.Also,Z±is ionic charge number.The positive(negative)kinematic viscosity η+(η?)are normalized by η+=and η?=The neutrality condition implies:

    for simplicity we shall consider(Z+=Z?=1).

    2.1 Nonlinear Calculations

    The slow stretched co-ordinates in(RPT)method[15]are given by:

    The speed of the wave λ and ? is a small real parameter.Expanding quantities in Eqs.(1)–(5)about their equilibrium values:

    The last equations are valid with conditions:|ξ|→ ∞,n?=n+=1,u+=0,? =0.Using Eqs.(8)and(9)into Eqs.(1)–(6)for quasi-neutrality condition at equilibrium,[39]the lowest-order in ? gives:

    The dispersion form is given by:

    The next equations of O(?2)yield:

    Put outN+2,N?2,?2,U+2,and U?2in Eqs.(12)–(16),one obtained the Burger equation for ?1:

    where

    Equation(17)admits the IA shock wave solution as

    whose amplitude equals 2B/A with χ(= ξ?2Bτ).

    The physical quantitiesN+2,N?2,U+2and U?2can be rewritten as:

    Equations for the next order in ? are given by:

    EliminatingN+2,N?2,U+2,U?2and ?3from Eqs.(21)–(25),we get a linearly inhomogeneous Burger type equation for ?1and ?2:

    where

    where the coefficients Ai(where i=1,2,...,4)are given by:

    In summary,our model reduced to nonlinear Burger equation(17)for ?1and Burger type equation(26)for ?2;source term(28)is a function ?1.

    3 Stationary Solution

    By using Eq.(19),Eq.(27)can be transformed into the form:

    where

    According to the homogeneous equation of Eq.(29)has two independent solutions,one of them is,(V)=sech2(χ),and the other,which can be derived using reduction of order method along with Able’s theorem,is given by(χ)=[χ/2+(1/4)sech(2χ)]sech2(χ).Using the variation of parameters method,[40?41]the particular solution of Eq.(29)can be written as

    where L1(ψ)and L2(ψ)are given by

    with

    Then,the formal stationary IA shock solution is given by:

    4 Model Results and Discussions

    Shock waves are studied in unmagnetized viscous positive negative ion plasmas.Numerical values have been introduced for Earth’s ionosphere(D-and F-regions).[1?2,22?23]According to the wave dissipation caused by kinematic viscosity,the studied system supports electrostatic shock waves.However,the main essential stimulus was to study the contribution of higher-order electric field structures associated to the shock waves.The comparison of lowest order and higher-order shock noise and associated electric field structures are shown in Fig.1.It is shown that higher-order decreases both steepness and amplitude of shock form and modulates the associated electric field structure.We have studied the e ff ectuation of plasma parameters such as the population of nonthermal electrons δ,the kinematic viscosities coefficient of positive negative ions η1and η2and the ion mass ratio Q(=m+/m?)on the dynamics formation of higher-order broadband electrostatic shock noise.For example,Fig.2 shows that,the increase of electron nonthermal parameter δ decreases shock steepness and amplitude.Accordingly,the amplitude and width of associated electric field of shock structure decreased also.On the other hand,the e ff ect of kinematic viscosity coefficients of positivenegative ions η1and η2on higher-order shock pro fi le ? and associated electric field structuresEfhave been examined in Figs.3–4.It is found that as η1and η2increase the steepness,amplitude of higher-order shock wave and higher-order electric field structures associated to the shock waves.The physical reason for this behavior is that the increase of kinematic viscosity coefficients increases the dissipation and consequently causes strong shock wave and associated electric field structures.Finally,the ratio raise of positive-negative mass Q decreases both wave amplitude and steepness of electrostatic shocks as shown in Fig.5.In summary,it has been noted that the involvement of higher-order e ff ects,positive-negative mass ratio Q,electron nonthermal parameter δ and kinematic viscosities coefficient of positive and negative ions η1and η2would regulate the countenance of ion electrostatic acoustic shock waves in D-and F-regions of Earth’s ionosphere.

    Fig.1 The comparison of lowest and higher-order shock pro fi le and associated electric field structures for Q=0.03,η1=0.3,η2=0.2,ν =0.5,and δ=0.2.

    Fig.2 Variation of higher-order shock pro fi le ? and associated electric field structures Efvs. χ and δ for Q=0.03,η1=0.3,η2=0.2,ν =0.5.

    Fig.3 Variation of higher-order shock pro fi le ? and associated electric field structures Efvs. χ and η1for Q=0.03,η2=0.2,ν =0.5,and δ=0.2.

    Fig.4 Variation of higher-order shock pro fi le ? and associated electric field structures Efvs. χ and η2for Q=0.03,η1=0.03,ν =0.5,and δ=0.2.

    Fig.5 Variation of higher-order shock pro fi le ? and associated electric field structures Efvs. χ and Q for η1=0.3,η2=0.2,ν =0.5,and δ=0.2.

    5 Conclusion

    Ion shock waves are discussed in three collisionless unmagnetized plasmas components having viscous fl uid of positive(+)and negative(?)ion and nonthermally electron distribution.The nonlinear Burger equation(17)for lowest order and linear inhomogeneous Burger type equation(26)for higher-order dissipation are obtained.Renormalization technique gives stationary solution for perturbation theory equations.It is emphasized that steepness and amplitude of higher-order shock waves are sensitive to higher-order e ff ects,positive-negative mass ratio Q,electron nonthermal parameter δ and kinematic viscosities coefficient of positive(negative)ions η1(η2).It is clear to con fi rm that the increase(decrease)of η1and η2(Q and δ)can lead to the increase of higher-order broadband electrostatic shock amplitude.The results obtained may be useful in understanding electrostatic shock noise in Earth’s ionosphere.

    References

    [1]R.Sabry,W.M.Moslem,and P.K.Shukla,Phys.Plasmas 16(2009)032302.

    [2]S.A.Elwakil,E.K.El-Shewy,and H.G.Abdelwahed,Phys.Plasmas.17(2010)052301.

    [3]H.Massey,Negative Ions,3rd ed.Cambridge University Press,Cambridge(1976).

    [4]A.J.Coates,F.J.Crary,G.R.Lewis,D.T.Young,J.H.Waite,and E.C.Sittler,Geophys.Res.Lett.34(2007)L22103.

    [5]H.Saleem,Phys.Plasmas 14(2007)014505.

    [6]W.Oohara,Y.Kuwabara,and R.Hatakeyama,Phys.Rev.E 75(2007)056403;W.Oohara and R.Hatakeyama,Phys.Plasmas 14(2007)055704.

    [7]R.Lundin,etal.,Nature(London)341(1989)609.

    [8]J.R.Asbridge,S.J.Bame,and I.B.Strong,J.Geophys.Res.73(1968)5777.

    [9]R.A.Cairns,A.A.Mamun,R.Bingham,R.Bostr¨om,R.O.Dendy,C.M.C.Nairns,and P.K.Shukla,Geophys.Res.Lett.22(1995)2709.

    [10]B.Sahu and R.J.Roychoudhury,Phys.Plasmas 13(2006)072302.

    [11]M.M.Masud,M.Asaduzzaman,and A.A.Mamun,Astrophysics and Space Science 343(2013)647.

    [12]S.A.Elwakil,A.M.El-hanbaly,A.Elgarayhi,E.K.El-Shewy,and A.I.Kassem,Advances in Space Research 54(2014)1786.

    [13]T.S.Gill,N.S.Saini,and K.Harvinder,Chaos,Solitons&Fractals 28(2006)1106.

    [14]H.G.Abdelwahed,E.K.El-Shewy,M.A.Zahran,and S.A.Elwakil,Phys.Plasmas 23(2016)022306.

    [15]H.Washimi and T.Taniuti,Phys.Rev.Lett.17(1966)996.

    [16]H.G.Abdelwahed and E.K.El-Shewy,Phys.Plasmas 19(2012)072301.

    [17]P.Chatterjee,G.Mondal,K.Roy,S.V.Muniandy,S.L.Yap,and C.S.Wong,Phys.Plasmas 16(2009)072102.

    [18]P.Chatterjee,K.Roy,S.V.Muniandy,and C.S.Wong,Phys.Plasmas 16(2009)112106.

    [19]A.E.Kalejahi,I.Kourakis,and P.K.Shukla,Phys.Plasmas 15(2008)(2008).

    [20]H.Asgari,S.V.Muniandy,and C.S.Wong,Phys.Plasmas 17(2010)063704.

    [21]E.K El-Shewy,M.A.Zahran,K.Schoepf,and S.A.Elwakil,Phys.Scr.78(2008)025501.

    [22]R.Blandford and D.Eichler,Phys.Rep.154(1987)1.

    [23]N.A.Strokin,Sov.Phys.J.Energy Theor.Phys.61(1985)6.

    [24]S.Hussain and N.Akhtar,Phys.Plasmas 20(2013)012305.

    [25]Y.Nakamura,H.Bailung,and P.K.Shukla,Phys.Rev.Lett.83(1999)1602.

    [26]P.K.Shukla and S.G.Tagare,Phys.Lett.A 59(1976)38.

    [27]A.Sarma and Y.Nakamura,Phys.Lett.A 373(2009)4174.

    [28]E.K.El-Shewy,H.G.Abdelwahed,and M.A.Elmessary,Phys.Plasmas 18(2011)113702.

    [29]A.M.El-Hanbaly,E.K.El-Shewy,A.Elgarayhi,and A.I.Kassem,Commun.Theor.Phys.64(2015)529.

    [30]E.K.El-Shewy,S.A.El-Wakil,A.M.El-Hanbaly,M.Sallah,and H.F.Darweesh,Astrophys.Space Sci.356(2015)269.

    [31]A.M.El-Hanbaly,M.Sallaha,E.K.El-Shewy,and H.F.Darweesh,J.Exp.Theor.Phys.121(2015)669.

    [32]R.A.Cairns,R.Bingham,P.Norreys,and R.Trines,Phys.Plasmas 21(2014)022112.

    [33]H.G.Abdelwahed,Phys.Plasmas 22(2015)092102.

    [34]S.Hussain,S.Mahmood,and Ur-Rehman,Hafeez,Phys.Plasmas 20(2013)06210.

    [35]M.Shahmansouri and A.A.Mamun,Phys.Plasmas 20(2013)082122.

    [36]H.G.Abdelwahed and E.K.El-Shewy,Commun.Theor.Phys.60(2013)445.

    [37]W.Masood and H.Rizvi,Phys.Plasmas 18(2011)042302.

    [38]W.Masood and H.Rizvi,Phys.Plasmas 19(2012)012119.

    [39]G.Mandal and P.Chatterjee,Verlag Z Naturforschung 0932(2010)0784.

    [40]S.K.El-Labany,J.Plasma Phys.54(1995)295.

    [41]Y.Kodama and T.Taniuti,J.Phys.Soc.Jpn.45(1978)298.

    国产aⅴ精品一区二区三区波| 最新中文字幕久久久久| 国产精品久久久久久精品电影| 哪里可以看免费的av片| 日韩精品中文字幕看吧| xxxwww97欧美| 国产成年人精品一区二区| 亚洲无线观看免费| 亚洲欧美日韩高清专用| 男女做爰动态图高潮gif福利片| 国内精品久久久久精免费| 一个人观看的视频www高清免费观看| 精品一区二区三区视频在线观看免费| 欧美日韩亚洲国产一区二区在线观看| 99九九线精品视频在线观看视频| 国产精品久久久久久久电影| 精品一区二区三区av网在线观看| 日日干狠狠操夜夜爽| 日本 av在线| 99久久九九国产精品国产免费| 日本黄色片子视频| 日韩强制内射视频| 午夜福利在线观看免费完整高清在 | 99久久精品一区二区三区| 欧美激情在线99| 少妇被粗大猛烈的视频| 中国美白少妇内射xxxbb| 免费在线观看成人毛片| 日韩强制内射视频| 亚洲美女黄片视频| 人妻制服诱惑在线中文字幕| 麻豆av噜噜一区二区三区| 免费高清视频大片| 永久网站在线| 久久精品国产鲁丝片午夜精品 | 人妻少妇偷人精品九色| 国产精品,欧美在线| 国产黄片美女视频| 免费人成在线观看视频色| 一进一出抽搐动态| 深爱激情五月婷婷| 午夜福利欧美成人| 国产高清视频在线播放一区| 亚洲午夜理论影院| 中文字幕免费在线视频6| 国内毛片毛片毛片毛片毛片| 精品久久久久久久久亚洲 | 久久精品久久久久久噜噜老黄 | 国产av麻豆久久久久久久| 男人和女人高潮做爰伦理| 丰满人妻一区二区三区视频av| 看免费成人av毛片| 亚洲不卡免费看| 给我免费播放毛片高清在线观看| 亚洲精品色激情综合| 欧美一区二区精品小视频在线| 国产aⅴ精品一区二区三区波| 久久午夜亚洲精品久久| 最近视频中文字幕2019在线8| 三级国产精品欧美在线观看| 免费观看精品视频网站| 午夜激情福利司机影院| 成年女人永久免费观看视频| 久久国产乱子免费精品| 亚洲国产欧洲综合997久久,| 亚洲av五月六月丁香网| x7x7x7水蜜桃| 欧美精品国产亚洲| 91午夜精品亚洲一区二区三区 | 国产精品综合久久久久久久免费| 可以在线观看毛片的网站| 性插视频无遮挡在线免费观看| 久久精品国产清高在天天线| 不卡一级毛片| 色av中文字幕| 国产精华一区二区三区| 国产亚洲91精品色在线| 九色国产91popny在线| 欧美成人性av电影在线观看| 国产主播在线观看一区二区| 变态另类成人亚洲欧美熟女| 免费看av在线观看网站| 国产精品av视频在线免费观看| 我的老师免费观看完整版| 观看免费一级毛片| 春色校园在线视频观看| 国产国拍精品亚洲av在线观看| 人人妻,人人澡人人爽秒播| 午夜日韩欧美国产| 免费在线观看成人毛片| 亚洲av一区综合| 我的女老师完整版在线观看| 国产男靠女视频免费网站| 搡老熟女国产l中国老女人| 亚洲人成伊人成综合网2020| 国产成人福利小说| 国产午夜精品久久久久久一区二区三区 | 欧美日韩国产亚洲二区| 老司机午夜福利在线观看视频| 日本一二三区视频观看| 欧美性猛交╳xxx乱大交人| 久久99热这里只有精品18| 老熟妇乱子伦视频在线观看| 美女被艹到高潮喷水动态| 欧美中文日本在线观看视频| 真人一进一出gif抽搐免费| 成人特级av手机在线观看| 他把我摸到了高潮在线观看| 12—13女人毛片做爰片一| 国产精品99久久久久久久久| 久久久精品大字幕| 特大巨黑吊av在线直播| 精品欧美国产一区二区三| 日本爱情动作片www.在线观看 | 亚洲图色成人| 午夜爱爱视频在线播放| 色播亚洲综合网| 久久精品综合一区二区三区| 老熟妇仑乱视频hdxx| 色5月婷婷丁香| 色尼玛亚洲综合影院| 两人在一起打扑克的视频| 国产精品久久视频播放| 国产精品女同一区二区软件 | 国产亚洲欧美98| 亚洲最大成人手机在线| 一级毛片久久久久久久久女| 亚洲成人中文字幕在线播放| 成人毛片a级毛片在线播放| 国产精品国产高清国产av| 国产在线男女| 麻豆av噜噜一区二区三区| 国产亚洲精品久久久com| 成人无遮挡网站| 国模一区二区三区四区视频| 噜噜噜噜噜久久久久久91| 美女高潮喷水抽搐中文字幕| 色在线成人网| 国产高潮美女av| 麻豆成人av在线观看| 日本-黄色视频高清免费观看| 亚洲中文字幕一区二区三区有码在线看| 男女啪啪激烈高潮av片| 亚洲自拍偷在线| 99热只有精品国产| 热99在线观看视频| 中文字幕av成人在线电影| 最近在线观看免费完整版| 亚洲最大成人av| 精品乱码久久久久久99久播| 色在线成人网| 亚洲真实伦在线观看| 亚洲精品亚洲一区二区| 国内少妇人妻偷人精品xxx网站| 麻豆成人av在线观看| 少妇的逼水好多| 日日夜夜操网爽| 日韩在线高清观看一区二区三区 | 我的老师免费观看完整版| 亚洲乱码一区二区免费版| 久久这里只有精品中国| 久久久成人免费电影| 国产成年人精品一区二区| 观看美女的网站| 高清毛片免费观看视频网站| 久久久色成人| 日本欧美国产在线视频| 欧美中文日本在线观看视频| 欧美极品一区二区三区四区| 可以在线观看毛片的网站| 亚洲在线自拍视频| 99久久精品一区二区三区| 午夜视频国产福利| 国产精品电影一区二区三区| 国产在线男女| 亚洲经典国产精华液单| 国产女主播在线喷水免费视频网站 | 五月伊人婷婷丁香| 男女做爰动态图高潮gif福利片| 国产黄a三级三级三级人| 丰满人妻一区二区三区视频av| 九九热线精品视视频播放| 欧美日韩中文字幕国产精品一区二区三区| 制服丝袜大香蕉在线| 在线免费十八禁| 中文在线观看免费www的网站| 一个人看视频在线观看www免费| 日本免费一区二区三区高清不卡| 99久久精品热视频| 国产精品爽爽va在线观看网站| 18禁在线播放成人免费| 深爱激情五月婷婷| 在线免费观看的www视频| 亚洲av成人av| 在线观看午夜福利视频| 欧美色视频一区免费| 免费观看的影片在线观看| 18禁黄网站禁片午夜丰满| 欧美色视频一区免费| 成人鲁丝片一二三区免费| 99精品在免费线老司机午夜| 国产精品乱码一区二三区的特点| 国产高清视频在线播放一区| 九九久久精品国产亚洲av麻豆| 国产黄a三级三级三级人| 最近中文字幕高清免费大全6 | 亚洲精华国产精华精| 国产亚洲av嫩草精品影院| www.www免费av| 在线观看午夜福利视频| 男人和女人高潮做爰伦理| 久99久视频精品免费| 非洲黑人性xxxx精品又粗又长| 热99re8久久精品国产| 老司机午夜福利在线观看视频| 午夜免费男女啪啪视频观看 | 22中文网久久字幕| 精品一区二区三区人妻视频| av天堂在线播放| 少妇被粗大猛烈的视频| 亚洲熟妇中文字幕五十中出| 床上黄色一级片| 丰满乱子伦码专区| 亚洲av熟女| 麻豆精品久久久久久蜜桃| 校园春色视频在线观看| 亚洲最大成人av| 午夜亚洲福利在线播放| 18禁在线播放成人免费| 精品免费久久久久久久清纯| 嫩草影院入口| 偷拍熟女少妇极品色| 久久6这里有精品| 免费观看的影片在线观看| 精品午夜福利视频在线观看一区| 国产精品一区二区免费欧美| 国产精品人妻久久久久久| 三级国产精品欧美在线观看| 一级a爱片免费观看的视频| 他把我摸到了高潮在线观看| 美女xxoo啪啪120秒动态图| 1024手机看黄色片| 国产69精品久久久久777片| 午夜日韩欧美国产| 久久久久久九九精品二区国产| 男人舔女人下体高潮全视频| 日韩精品中文字幕看吧| 三级国产精品欧美在线观看| 国产午夜精品久久久久久一区二区三区 | 天美传媒精品一区二区| 久久久色成人| 亚洲图色成人| 国产成人一区二区在线| 人人妻,人人澡人人爽秒播| 九九久久精品国产亚洲av麻豆| 国产一区二区三区在线臀色熟女| 黄色女人牲交| 免费大片18禁| 久久这里只有精品中国| 99九九线精品视频在线观看视频| 男人舔女人下体高潮全视频| 国产一区二区三区在线臀色熟女| 亚洲欧美清纯卡通| 欧美xxxx黑人xx丫x性爽| 99久久精品国产国产毛片| 欧美xxxx黑人xx丫x性爽| 精品无人区乱码1区二区| 成年女人毛片免费观看观看9| 在线播放国产精品三级| 精品欧美国产一区二区三| 他把我摸到了高潮在线观看| 日本与韩国留学比较| 亚洲精品色激情综合| 国产高清有码在线观看视频| 99国产精品一区二区蜜桃av| av中文乱码字幕在线| 成年女人看的毛片在线观看| 国产熟女欧美一区二区| 91av网一区二区| 国产精品av视频在线免费观看| 亚洲成人中文字幕在线播放| 国产高清视频在线播放一区| 午夜影院日韩av| 波多野结衣高清作品| 精品久久久久久久久av| 3wmmmm亚洲av在线观看| 国产蜜桃级精品一区二区三区| 国产高清视频在线观看网站| 成年人黄色毛片网站| 久久精品国产亚洲网站| 日日摸夜夜添夜夜添小说| 精品人妻1区二区| 日韩欧美免费精品| 午夜激情欧美在线| 国产高清三级在线| 一个人看视频在线观看www免费| 天堂av国产一区二区熟女人妻| 亚洲午夜理论影院| 午夜免费男女啪啪视频观看 | 大型黄色视频在线免费观看| 2021天堂中文幕一二区在线观| 日本 av在线| 在线观看美女被高潮喷水网站| 久久国内精品自在自线图片| 99久久成人亚洲精品观看| 啦啦啦韩国在线观看视频| 真人做人爱边吃奶动态| 波野结衣二区三区在线| 永久网站在线| 成人毛片a级毛片在线播放| av中文乱码字幕在线| 全区人妻精品视频| 成人特级黄色片久久久久久久| avwww免费| 国产一区二区三区在线臀色熟女| videossex国产| 免费在线观看成人毛片| 久久久久精品国产欧美久久久| 18+在线观看网站| 美女高潮的动态| 午夜精品久久久久久毛片777| 免费人成视频x8x8入口观看| 女人被狂操c到高潮| 国产色婷婷99| 伊人久久精品亚洲午夜| 午夜精品一区二区三区免费看| 精品久久久久久久久久久久久| 欧美+日韩+精品| 国产三级中文精品| 久久亚洲精品不卡| 极品教师在线免费播放| 欧美极品一区二区三区四区| 尾随美女入室| 亚洲人成网站在线播放欧美日韩| 婷婷精品国产亚洲av在线| 天堂动漫精品| 色精品久久人妻99蜜桃| 精品日产1卡2卡| 国产av一区在线观看免费| 午夜久久久久精精品| 国产精品98久久久久久宅男小说| 国产伦精品一区二区三区视频9| 精品免费久久久久久久清纯| 一本一本综合久久| 真人做人爱边吃奶动态| 22中文网久久字幕| 久久精品夜夜夜夜夜久久蜜豆| 日本精品一区二区三区蜜桃| 国产精华一区二区三区| 乱码一卡2卡4卡精品| 免费人成视频x8x8入口观看| 美女cb高潮喷水在线观看| 中文字幕免费在线视频6| 在线观看66精品国产| 欧美一区二区精品小视频在线| 久久中文看片网| 国产高清视频在线观看网站| 99精品久久久久人妻精品| 伦精品一区二区三区| 亚洲美女黄片视频| 国产精品免费一区二区三区在线| 午夜爱爱视频在线播放| 国产午夜精品论理片| 全区人妻精品视频| 亚洲av免费在线观看| 国产精品精品国产色婷婷| 精品欧美国产一区二区三| 窝窝影院91人妻| 亚洲人成网站在线播放欧美日韩| 一进一出抽搐gif免费好疼| 国产精品自产拍在线观看55亚洲| 国产精品嫩草影院av在线观看 | 亚洲七黄色美女视频| 午夜免费激情av| 女人被狂操c到高潮| 真实男女啪啪啪动态图| 少妇熟女aⅴ在线视频| 日韩中字成人| 69人妻影院| 国产精品美女特级片免费视频播放器| 赤兔流量卡办理| 亚洲成人免费电影在线观看| 99久久中文字幕三级久久日本| 99国产精品一区二区蜜桃av| 校园春色视频在线观看| 美女被艹到高潮喷水动态| 欧美日本视频| eeuss影院久久| 日本 欧美在线| 最近最新中文字幕大全电影3| 熟女电影av网| 国产精品综合久久久久久久免费| 国产免费av片在线观看野外av| 久久精品影院6| 春色校园在线视频观看| 免费在线观看日本一区| 变态另类成人亚洲欧美熟女| 人妻夜夜爽99麻豆av| 变态另类丝袜制服| 1024手机看黄色片| 91精品国产九色| 美女被艹到高潮喷水动态| 黄色一级大片看看| 久久精品人妻少妇| 国产高清视频在线观看网站| 欧美日韩中文字幕国产精品一区二区三区| 舔av片在线| 亚洲精品影视一区二区三区av| 最后的刺客免费高清国语| 99riav亚洲国产免费| x7x7x7水蜜桃| 人妻制服诱惑在线中文字幕| 亚洲精品成人久久久久久| 超碰av人人做人人爽久久| 51国产日韩欧美| 啦啦啦观看免费观看视频高清| 在线天堂最新版资源| 久久99热这里只有精品18| 我要搜黄色片| 成人av在线播放网站| 99久久成人亚洲精品观看| 国产激情偷乱视频一区二区| 成人av一区二区三区在线看| 日韩精品青青久久久久久| 免费看美女性在线毛片视频| 99久久精品国产国产毛片| 久久人妻av系列| 亚洲性久久影院| 日韩中字成人| 亚洲七黄色美女视频| 亚洲精品乱码久久久v下载方式| 网址你懂的国产日韩在线| 国产不卡一卡二| 99九九线精品视频在线观看视频| 毛片女人毛片| 欧美丝袜亚洲另类 | 丝袜美腿在线中文| 国产一区二区亚洲精品在线观看| 真人一进一出gif抽搐免费| 午夜福利成人在线免费观看| 国产精品98久久久久久宅男小说| 午夜影院日韩av| a级毛片免费高清观看在线播放| 99久久精品国产国产毛片| 一边摸一边抽搐一进一小说| aaaaa片日本免费| 一个人看的www免费观看视频| 日日撸夜夜添| 春色校园在线视频观看| 亚洲国产色片| 久久精品国产亚洲av涩爱 | 国产高潮美女av| 不卡视频在线观看欧美| 91av网一区二区| 91久久精品国产一区二区三区| 中亚洲国语对白在线视频| 18+在线观看网站| 成人国产麻豆网| 亚洲七黄色美女视频| 狂野欧美激情性xxxx在线观看| 亚洲欧美日韩高清在线视频| 日韩欧美免费精品| 国产av不卡久久| 国产不卡一卡二| 此物有八面人人有两片| 赤兔流量卡办理| 两个人视频免费观看高清| 国产成人av教育| 久久精品综合一区二区三区| 制服丝袜大香蕉在线| 一a级毛片在线观看| 日本 av在线| 久久午夜福利片| 国产在视频线在精品| 日日摸夜夜添夜夜添av毛片 | 97碰自拍视频| 免费高清视频大片| 欧美性猛交╳xxx乱大交人| 高清毛片免费观看视频网站| 亚洲性夜色夜夜综合| 亚洲内射少妇av| 最近中文字幕高清免费大全6 | 国产高清三级在线| 熟女电影av网| 他把我摸到了高潮在线观看| 精品免费久久久久久久清纯| 免费看av在线观看网站| 国产伦一二天堂av在线观看| 精品乱码久久久久久99久播| 一级av片app| 久久久久精品国产欧美久久久| 乱码一卡2卡4卡精品| 午夜精品久久久久久毛片777| 99精品久久久久人妻精品| 国产精品电影一区二区三区| 亚洲成人免费电影在线观看| 亚洲欧美日韩无卡精品| 日本a在线网址| 特大巨黑吊av在线直播| 欧美最新免费一区二区三区| 五月玫瑰六月丁香| 无人区码免费观看不卡| 一本精品99久久精品77| 日本免费一区二区三区高清不卡| 一级a爱片免费观看的视频| 嫩草影院精品99| 亚洲av第一区精品v没综合| 欧洲精品卡2卡3卡4卡5卡区| 亚洲一区高清亚洲精品| 欧美+日韩+精品| 欧美黑人欧美精品刺激| 久久久久久久午夜电影| 成人性生交大片免费视频hd| 老女人水多毛片| 国内少妇人妻偷人精品xxx网站| 校园人妻丝袜中文字幕| 国产一区二区亚洲精品在线观看| 毛片女人毛片| 非洲黑人性xxxx精品又粗又长| 亚洲欧美日韩高清专用| 国产精品美女特级片免费视频播放器| 国产又黄又爽又无遮挡在线| 在线观看av片永久免费下载| 欧美性猛交黑人性爽| 亚洲国产精品久久男人天堂| 亚洲va日本ⅴa欧美va伊人久久| av福利片在线观看| 99久久精品热视频| 精品一区二区三区视频在线| 久久99热6这里只有精品| 亚洲精品乱码久久久v下载方式| 成人国产综合亚洲| 精品久久久久久久久亚洲 | 亚洲,欧美,日韩| 99视频精品全部免费 在线| 一a级毛片在线观看| 亚洲国产欧洲综合997久久,| 99久久精品国产国产毛片| 成人精品一区二区免费| 又粗又爽又猛毛片免费看| 精品午夜福利在线看| 国产精品久久视频播放| 成人综合一区亚洲| 1000部很黄的大片| 精品久久久久久久久av| 韩国av在线不卡| 亚洲国产精品合色在线| 三级国产精品欧美在线观看| 他把我摸到了高潮在线观看| 22中文网久久字幕| 男人舔奶头视频| 国产伦人伦偷精品视频| 日本黄色片子视频| 女同久久另类99精品国产91| 天堂√8在线中文| 我要看日韩黄色一级片| 欧美一级a爱片免费观看看| 一a级毛片在线观看| 一个人观看的视频www高清免费观看| 色5月婷婷丁香| 精品久久久久久久久亚洲 | 美女免费视频网站| av女优亚洲男人天堂| 国产精品一区二区三区四区免费观看 | 国产在视频线在精品| 国语自产精品视频在线第100页| 午夜亚洲福利在线播放| 成人综合一区亚洲| 欧美日韩国产亚洲二区| 亚洲自偷自拍三级| 亚洲成人久久爱视频| 日本成人三级电影网站| 精品一区二区三区人妻视频| 少妇裸体淫交视频免费看高清| 99久国产av精品| 国内精品美女久久久久久| 嫩草影院入口| 欧美潮喷喷水| av.在线天堂| 亚洲aⅴ乱码一区二区在线播放| 好男人在线观看高清免费视频| 日本在线视频免费播放| 欧美+亚洲+日韩+国产| 丰满人妻一区二区三区视频av| 亚洲久久久久久中文字幕| 国产一区二区三区av在线 | 久久香蕉精品热| 一进一出好大好爽视频| 美女高潮的动态| 嫩草影视91久久| 成人国产麻豆网| 在线免费观看不下载黄p国产 | 小蜜桃在线观看免费完整版高清| 国产熟女欧美一区二区| 偷拍熟女少妇极品色| 精品久久久久久成人av| 国产高清三级在线| 欧美日韩综合久久久久久 | 国产一区二区三区av在线 | 两个人的视频大全免费| 国产高清三级在线| 91狼人影院| 久久久久久久久久黄片| 国内精品宾馆在线| 国产成人aa在线观看| 欧美激情久久久久久爽电影| 亚洲国产日韩欧美精品在线观看| 天天一区二区日本电影三级| 看片在线看免费视频| 国产伦精品一区二区三区四那| 欧美日本亚洲视频在线播放| 国产精品久久视频播放| 色综合婷婷激情| 99热只有精品国产| 特大巨黑吊av在线直播|