• <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 ?

    銀納米晶對鉺鐿共摻的TeO2-WO3-La2O3微晶玻璃發(fā)光性能的影響

    2018-07-04 06:15:30陳淑文張文俊
    無機化學學報 2018年7期
    關鍵詞:微晶學報

    陳淑文 林 健 張文俊

    (同濟大學材料科學與工程學院,教育部先進土木工程材料重點實驗室,上海 201800)

    0 Introduction

    Tellurite glasses have many advantages such as wide range of transparency,large optical nonlinearity,refractive index and density,high solubility of rareearth (RE)ions,as well as low phonon energy compared to other oxide glasses[1].These characteristics make RE doped tellurite glasses promising candidates for the optical fiber amplifier,laser and new band optical communication[2].Er3+-doped tellurite glass has generated considerableinterest duetotheirfavorable emissions of blue,red,green and near-infrared light[3].Yb3+is known as a resourceful dopant can enhance the luminescence emissions of Er3+due to its large absorption cross-section.What′s more,the resonance energy transfer between Yb3+and Er3+can significantly improve the pumping efficiency of Er3+,and improve the upconversion (UC)properties of glasses[4].However,the luminous intensity of RE doped tellurite glasses is still weaker than some luminescent crystals[5].

    Over the last few years,glass-ceramics have attracted great interest because of their prospective applications as promising hosts for RE ions.The formation of micro-crystals in the glass can greatly change the coupled environment around RE ions,and reduce the covalence of crystal field as well as the vibration energy of lattice[6].Gao et al.[7]obtain NaYF4∶Tb3+,Yb3+,Li+crystallites in silicate oxide system.RE ions are gathering around the micro-crystals,which increases the probability of the energy transfer between RE ions,and improves the luminous performance of the glasses.In addition,the simple process of preparation and synthesis makes RE ions doped glassceramics become important UC luminescence materials.Ansari et al.[8]report the synthesis of YbF3/ErF3-codoped lithium tungsten tellurite oxyfluoride glass-ceramicscontain LiYbErF4nanocrystals.An intense visible emission originated from Er3+can be observed due to the cooperative UC processed 980 nm excitation.

    The localized surface plasmon resonance (LSPR)can increase the local field on the RE ions which near the metal nanoparticles and transferring energy to the RE ions,When the incident light wavelength or photoluminescence (PL)wavelength of the glass is close to the localized surface plasmon resonance wavelength,due to the local field enhancement(LFE)and energy transfer (ET)from Ag to RE ions,the luminescence intensity of glasses can be enhanced[9].Therefore,inorganic glasses doped with silver nanocrystals(Ag NPs)have received considerable attention[10]due to their unique optical properties[11].Amjad et al.[12]report significant luminescence enhancement of Er3+ions as well as raman intensity of Ag NPs embedded zinctellurite glasses.The radiative transition of Er3+ions and Ag NPs induce the electric dipoles,leading to the enhancement of PL[2-13].Ma et al.[14]successfully introduce Ag NPs into SiO2-Al2O3-CaF2system and obtain the glass-ceramics containing CaF2crystallites with significant enhanced luminous intensity.To our best knowledge,the study oftellurite glass-ceramics containing Ag NPs is rare.

    In this paper,we report the optical properties of Er3+/Yb3+co-doped tellurite glass-ceramics containing Ag NPs.The effect of different introducing ways of Ag NPs on the UC luminescence properties of Er3+/Yb3+co-doped tellurite glass-ceramics were systematically investigated.Ourstudy furtherdemonstrates the luminescent intensity of the sample co-doped with AgCl and AgNO3has the better UC luminescence properties than the sample which was single doped with AgCl or AgNO3.Tellurite glass-ceramics doped with RE ions and Ag NPs are promising candidates for the development of lasers and optical amplifiers for PL based devices.

    1 Experimental

    1.1 Material preparation

    Tellurite glasses with compositions 69TeO2-23WO3-8La2O3(TWL)containing fixed concentration of Er3+(0.5% (n/n),Yb3+(1.0% (n/n),AgCl(0~2.0% (w/w))and AgNO3(0~3.0% (w/w)were prepared by conventional melt-quenching method,melting anhydrous mixtures of TeO2(99.99%),La2O3(99.99%),Er2O3(99.99%),Yb2O3(99.99%),WO3(99.99%),AgCl (99.9%)and AgNO3(99.9%).A gold crucible containing the glass constituents was placed in an electric furnace at(790±10)℃ for 15 min and the melt was poured onto a preheated stainless steel plates.Subsequently,the samples were annealed at 380℃for 2 h to remove the thermal and mechanical strains completely.The samples were then cooled down to the room temperature.69TeO2-23WO3-8La2O3-0.5%Er2O3-1.0%Yb2O3(TWL-ErYb base glass)and 69TeO2-23WO3-8La2O3-0.5%Er2O3-1.0%Yb2O3-1.0%AgCl (TWL-ErYb-1AgCl)glasses were heat treated at different heat treatment conditions and other samples were heat treated at appropriate heat treatment condition(at 390 ℃ for 15 min)to form glass ceramics.The samples heat treated at different temperatures (T)and times (t)are denoted as T-t.Finally,all the samples were cut and polished for the structural and optical measurements.

    1.2 Characterizations

    Differential thermal analysis (DTA)measurement(NETZSCH STA 449C)was carried out by heating about 0.02 g of glass powder in alumina crucible at the heating rate of 10 K·min-1from 200 to 800℃.The used atmosphere in DTA was N2,and the gas flow was set as 40 mL·min-1.The DTA results of samples were referenced to that of alumina powder.Phase identification of the samples was performed by X-ray diffraction (XRD)analysis with Cu Kα (λ=0.154 06 nm,35 kV,30 mA)radiation (D8 Advance,Bruker Inc.,Germany)at room temperature in the 2θ range of 10°~70°with a step size of 0.02°and a step scanning time of 1 s.The UV-NIR absorption spectra of glasses were recorded by a UV-4100 UV/VIS/NIR spectrophotometer in the range of 400~1 100 nm.The fluorescence spectrometer (Model Omni-λ300 Zolix),together with aphotomultiplierdetector (PMTH-SI-CR131)were used to measure the luminescence spectra under 980 nm diode laser within the range of 500~700 nm.Laser power is 194 mW and focusing methodology is lens focusing.Standard sample was used to compare the intensity between different spectra.Luminescence decay times in the microsecond time scale was measured on an Edinburgh FLSP920 spectrophotometer.All spectroscopic measurements were performed at room temperature.The characterizations of nanocrystal or microcrystal in glasses were carried out by a Transmission electron microscopy (TEM)(JEM-2100)with an accelerating voltage of 200 kV.The samples were grinded into fine powders in an agate mortar.Subsequently,the powders were dissolved in ethanol and then dispersed by supersonic before the solution was dropped on the copper grid.

    2 Results and discussion

    2.1 Effect of micro-crystallization on luminescence of the TWL-ErYb glasses

    Comparing to the base glass,appropriate microcrystallization can improve the strength and thermal stability of glass.For example,oxyfluoride glassceramics doped with RE ions show higher chemical and mechanical stability and lower phonon energy than fluoride glasses[7].

    The transparent TWL-ErYb glass-ceramics were prepared by appropriate heat treating.The absorption spectra of TWL-ErYb glasses before and after heat treatment at 390℃for 15 min are presented in Fig.1.After heat treatment,the absorption edge shows no obvious shift.The spectra exhibit a number of distinct absorption bands around 974,800,654,544,522 and 499 nm,which can be well assigned as the electronic transitions of Er3+from its ground4I15/2state to the4I11/2,4I9/2,4F9/2,4S3/2,2H11/2and4F7/2excited states,the absorption bands around 974 nm also include the electronic transitions of Yb3+from its ground2F7/2state to the2F5/2besides[15].This result clearly shows that Er3+ions exists in the glass.In order to further check whether microcrystals were formed,the samples were characterized by TEM,instead of the XRD which is found to be hard to detective small amount of nanometer size micro-crystals in the glass.

    Fig.1 Absorption spectra of TWL-ErYb glasses before and after heat treatment(390 ℃-15 min)

    Fig.2 shows representative HR-TEM images of TWL-ErYb base glass after heat treatment at 390℃for 15 min.There were many micro-crystals precipitated in the glass,and the size of micro-crystals varies from 40 to 150 nm.The measurement results of crystalline inter-planar space are 0.357 14 and 0.329 8 nm,corresponding to the (311)plane of Er2WO6(PDF No.38-0102)andLa2(WO4)3(PDF No.19-0669).For this reason,it can be inferred that Er3+ions have been incorporated into micro-crystals,which hasbeen demonstrated to improve the efficiency of the UC luminescence to a certain extent[16].

    Fig.2 HR-TEM images of TWL-ErYb base glass with heat treatment(390 ℃-15 min)and (b,c)are the enlarged view of(a)

    Fig.3 shows the UC emission spectra of TWLErYb base glasseswith differentheattreatment temperatures under the excitation of 980 nm.Three UC emission bands that located at 538,557 and 674 nm can be clearly observed,which can be assigned to2H11/2→4I15/2,4S3/2→4I15/2and4F9/2→4I15/2transitions of Er3+ions,respectively[17].With the increase of heat treatment temperature,luminous intensity of each band gradually enhanced.As shown in Fig.1,after heat treatment,the transmittance of glass declined,to the contrary,the intensity of RE absorption peaks accordingly increased and the non-radiative-relaxation influences which caused by RE ions co-doping can be eliminated due to the lower phonon energy of glass ceramics[18].

    Fig.3 Up-conversion emission spectra of TWL-ErYb base glasses for different heat treatment temperatures with the same treatment time of 15 min

    What′s more,comparing to the red emission (674 nm),the enhancement of the green emission (557 nm)is more obvious (Fig.3).However,the enhancement ofluminescencecaused bymicro-crystalsisnot significant because of the incomplete structure of micro-crystals. Even when the heat treatment temperature was raised to 410℃,due to the overgrowth of micro-crystals,the luminous intensity of the glass was decreased.In order to investigate the luminescence mechanism of RE ions in glasses,the power dependence of UC emission intensity for TWLErYb base glasses without and with heat treatment at 390℃for 15 min were studied,as shown in the inset of Fig.3.The slope (n)for 557 nm wavelength of the sample without heat treatment was 1.84,and the sample with heat treatment at 390℃for 15 min was 1.71.The result confirms that the green emission (557 nm)originates from the two-photon process absorption of Er3+ions,and micro-crystallization has little effect on the UC mechanism of Er3+and Yb3+ions[19].

    2.2 Effect of AgCl on luminescence of the TWLErYb glasses

    Introducing Ag NPs into RE ions doped glasses can effectively alter the free space spectral properties of RE ions and enhance the yield of their weak optical transitions[20-21].It is common to introduce AgCl as source of silver in glasses.The introduction of AgCl can reduce the glass transition temperature (Tg)of glass and open the network structure of the glass well,leading to the precipitation of Ag NPs easily despite of the small solubility of AgCl in glass[22].

    In order to study the effect of Ag NPs on the micro-crystallization process,XRD patterns of TWLErYb and TWL-ErYb-1AgCl glasses with different heat treatment conditions (Fig.4(a~c)and DTA curves of TWL-ErYb and TWL-ErYb-1AgCl glasses (Fig.4(d))at the heating rate of 10 K·min-1from 200 to 800 ℃were measured.Tgand the first crystallization temperature (Tc1),the second crystallization temperature (Tc2)and the third crystallization temperature (Tc3)are pointed by the arrow in the Fig.4(d).When the glasses were been heat treated at 420℃for 24 h,TWL-ErYb base glass was still transparent and TWL-ErYb-1AgCl glass became purple.There is no obvious crystallization peak on the XRD patterns,which may be caused by the small content of microcrystal and Ag NPs.When the glasses were been heat treated at 500℃for 24 h and 640℃for 24 h,the glasses were all opaque.The crystalline peaks oflanthanum tellurium oxides compounds were observed in Fig.4(b,c).In addition,crystallization peaks of TWL-ErYb-1AgCl glasses are more obvious than TWL-ErYb base glass.Therefore,the Ag NPs are expected to be the nucleation agent and promote the precipitation of microcrystals.In general,this kind of glass is very stable and Ag NPs will not destroy the structure of the glass at a moderate heat treatment temperature.

    The absorption spectra ofTWL-ErYb-1AgCl glasses with different heat treatment conditions are shown in Fig.5.After introducing Ag NPs into the glass,the absorption peak positions didn′t change.However,with the growth of Ag NPs caused by the increase of heat treatment temperature,the transmittance of TWL-ErYb glass with Ag NPs decreased.When the heat treatment temperature was raised to 460℃,in addition to the intrinsic absorption peaks of RE ions,the LSPR peak of Ag NPs was detected at the range of 500~650 nm[23].The emergence of the LSPR peak means that the content of Ag NPs increased significantly in the glass.

    Fig.6(a)presents the HR-TEM image of TWLErYb-1AgCl glass with heat treatment at 390℃for 15 min.The shapes of Ag NPs are mainly spherical and ellipsoidal.Moreover,the size of Ag NPs is about 4~6 nm,while the size of micro-crystals is about 6~8 nm.The lattice fringes can be clearly observed in an enlarge image Fig.6(b).The interplanar spacing of NPs is 0.238 1 nm,corresponding to the (111)plane of silver crystal (PDF No.65-8424).These results prove the precipitation of Ag NPs in TWL-ErYb-1AgCl glass.It is important to note that,in the Fig.6(c),we can find the precipitation of La2WO6micro-crystals around the Ag NPs.However,the number of Ag NPs is overall dominant.

    Fig.4 XRD patterns of TWL-ErYb and TWL-ErYb-1AgCl glasses with different heat treatment conditions of(a)420 ℃-24 h,(b)500 ℃-24 h and (c)640 ℃-24 h;(d)DTA curve of TWL-ErYb and TWL-ErYb-1AgCl glasses

    Fig.5 Absorption spectra of TWL-ErYb-1AgCl with different heat treatment

    Fig.6 TEM images of the sample TWL-ErYb-1AgCl heat treated at 390℃for 15 min

    AgNPsareformedfrom AgClorAgNO3throughout the melting procedure and grown during the annealing.The reduction of the Ag NPs can be discussed by the reduction potentials (E0)of redox system elements,as[24]:

    Following reduction processes are likely to ensue:

    where ΔE0is the total potential of reduction process.The equation (5~7)are all feasible reactions (with ΔE0>0).Therefore,these reactions guarantee the presence of Ag NPs in the system in addition to the absorption spectra results and TEM images.

    The luminescence spectra of TWL-ErYb-1AgCl glasses with different heat treatment conditions were studied,the results are shown in Fig.7.After heat treatment,all of the samples obtained the stronger emissions.The sample with heat treatment at 390℃for 15 min acquired the best luminescence property.In this heat treatment condition,Ag NPs precipitated a lot and the average size of the micro-crystals was small.A lot of precipitations of Ag NPs,leading to short distance between Ag NPs and Er3+ions,made the energy transfer from Ag NPs to Er3+ions become a possible explanation for the enhanced luminescence[25].The non-resonance excitation light excites the d-band electron to unoccupied sp-conduction band[1].Subsequently,electron and hole recombine and moves to Fermi level through a phonon-electron interaction.Therefore,luminescence is mainly in visible region[26].The local electric field change cause the enhancement of photoluminescence and the effective electric field)can be written as[17]:

    Fig.7 Up-conversion emission spectra of TWL-ErYb-1AgCl glasses at different heat treatment conditions

    here ε0is the dielectric constant in the presence of an external electromagnetic field of amplitude,q is the nanocrystal specific volume,ωpis the plasma frequency,i is the ground level,and γ is the damping of the resonance.The damping γ is the contribution of the conduction electrons and it can be described as[2]:

    The first term 1/τ0is related to the bulk electron scattering process in the nanoparticle.The interaction between quasi-electron-free and the surface of a sphere causes the second term,where VFis the Fermi velocity,D is the mean core particle size,and gsis the surface factor[26].The shape of the NPs is related to surface plasmon resonance (SPR)and the appropriate size of the NPs can enhance local field[27].Therefore,the glass with more Ag NPs,fewer micro-crystals,as well as high transmittance can obtain the enhancement of the luminescence property[28].The inset of Fig.7 showsthedependenceoftheUC luminescence intensity on the 980 nm pump laser power for 557 nm.The slope (n)for 557 nm wavelength of the sample without heat treatment was found to be 1.87,and the sample with heat treatment at 390℃for 15 min was found to be 2.05.This experimental result confirms that the green emission (557 nm)is due to the twophoton process absorption of Er3+ions.It is worth noting that the slope (n)of the glass doped with Ag NPs is larger than the tellurite base glass (Fig.4),which implies that Ag NPs can promote the two-photon absorption of Er3+ions in the process of the energy transfer and promote particles jump to a high level[29].

    Under the appropriate heat treatment condition at 390℃for 15 min,the up-conversion emission spectra of the glasses with different contents of AgCl are shown in Fig.8.The co-doped AgCl samples are denoted as TWL-ErYb-xAgCl(x=0~2% (w/w).The reduction and growth ofAg nanocrystalsgenerate an efficient localized electric field around the Ag NPs.The local electric field can increase the rate of excitations of Er3+ions in vicinity of Ag NPs.As a result,the rates of transitions from emitting levels are enhanced[29].According to our testing results,the glass sample containing 0.75% (w/w)AgCl shows the maximum intensity enhancement.Furthermore,we find that the glass will be opaque after introducing 2%(w/w)AgCl into the glass.It means that doping content of AgCl is limited.

    Fig.8 Up-conversion emission spectra of TWL-ErYbxAgCl with heat treatment temperature (390 ℃-15 min)

    2.3 Effect of co-doped AgCl and AgNO3on luminescence of the TWL-ErYb glassceramics

    Ag NPs can be produced by the introduction of AgCl,however,itwillcause the overgrowth of microcrystals at the same time.In order to find a better way to increase the precipitation of Ag NPs,the effect of different contents of AgNO3on luminescence of TWL-ErYb glass-ceramics has been studied,and the luminescence spectra are shown in Fig.9.The single doped AgNO3samples are denoted as TWLErYb-yAgNO3(y=0~3%, (w/w).Under the heat treatment condition at 390℃for 15 min,the glass sample containing 2.5% (w/w)AgNO3shows the maximum intensity enhancement.Under the condition of large content,the luminescent property of the glass single doped AgNO3is better than that with single doped AgCl.However,the UC emission intensity enhancement of the glasses doped with a small content of AgNO3is not obvious.Besides,it was difficult to find Ag NPs in the TEM images of TWL-ErYb-2.5AgNO3.It is not easy for AgNO3to generate Ag NPs in the glasses.Therefore,we consider co-doping AgCl and AgNO3to inhibitthe precipitation of AgCl crystals and introduce more Ag+ions into the glasses.

    Fig.9 Up-conversion emission spectra of TWL-ErYbyAgNO3with heat treatment temperature(390℃-15 min)

    We studied the effect of the proportion of AgCl and AgNO3on luminescent properties,the results are shown in Fig.10.The single doped AgCl and AgNO3samples are denoted as TWL-ErYb-xAgCl-yAgNO3(x=0~1%,y=0~1%,(w/w)and the proportion of AgCl and AgNO3is x∶y.The luminescent intensity of the glass co-doped with AgCl and AgNO3was stronger than the glass which was single doped with AgCl or AgNO3.The sample with x ∶y=0.5 ∶0.5 displayed the highest luminescence intensity.The glass with x∶y=0.7∶0.3 show the better luminescence intensity than the glass with x∶y=0.3∶0.7,which proves that AgCl can have greater effect on fluorescence enhancement of glasses when the content of silver source is limited.However,when x∶y=1∶1,the glass didn′t obtain further enhanced luminescence intensity.The luminescence microsecond time resolution were performed on the luminescence of the Er3+ions in TWL-ErYb base glass and TWL-ErYb-0.5AgCl-0.5AgNO3glass.The samples were excited at 823 nm,and the decay curves were detected at 557 nm,as described in Fig.11.Both the luminescence decays are well fitted to single exponential decay function,the calculated lifetime of the Er3+ions in TWL-ErYb base glass (τEr)and TWL-ErYb-0.5AgCl-0.5AgNO3glass (τErAg)is 81.001 and 95.081 μs,respectively.The energy transfer between Ag NPs and Er3+ions and the effect of LSPR enhanced emission are might responsible for the longer lifetime of the glass with Ag NPs[30].Zhang et al[31].also find a longer lifetime of Er3+ions (4I13/2)in TeO2-WO3-La2O3-AgNO3glass than TeO2-WO3-La2O3glass.

    Fig.10 Up-conversion emission spectra of TWL-ErYbxAgCl-yAgNO3glasses with heat treatment temperature (390 ℃-15 min)

    Fig.11 Luminescence decay curves of the Er3+ions in TWL-ErYb base glass and TWL-ErYb-0.5AgCl-0.5AgNO3glass

    LSPR and plasma coupling effectbetween particles make the effective enhancement of local electric field near the nanoparticles,leading to the increase of the radiative transition probability of each energy level of Er3+ions,which eventually makes luminescence emission enhanced.Comparing to LSPR and plasma coupling effect,the energy transfer between Ag NPs and Er3+ions is however the secon-dary factor lead to the enhancement of luminescence[30].Besides,micro-crystallization can decrease the phonon energy of glasses,and boost the energy level transition probability of RE ions[32].

    Fig.12 TEM images of the sample TWL-ErYb-0.5AgCl-0.5AgNO3annealed at 380 ℃ for 2 h:(a)is the enlarged view of(c)and (b)is the enlarged view of(a)

    TWL-ErYb-0.5AgCl-0.5AgNO3glasswith heat treatment at 390℃for 15 min shows the maximum enhancement and the HR-TEM images of the glass are shown in Fig.12.A large number of Ag NPs in uniform distribution were observed.The shapes of Ag NPs are mainly spherical and ellipsoidal.It can be clearly seen the regular arrangement of silver atoms,and the size is about 4~6 nm.However,we didn′t find micro-crystals in this TEM image.It is probably that the amount of Cl-ions of TWL-ErYb-0.5AgCl-0.5AgNO3glass is less than TWL-ErYb-1AgCl glass.The effect of AgCl on the precipitation of microcrystals becomes weak,and the glass becomes more stable.Therefore,the precipitation of micro-crystals wasnotobviousinTWL-ErYb-0.5AgCl-0.5AgNO3glass.Besides,TWL-ErYb-0.5AgCl-0.5AgNO3glass can provide the same amount of Ag+ions comparing to the TWL-ErYb-1AgCl glass.According to the above results,we conclude the follow results: (1)The introduction of AgCl can be helpful to produce Ag NPs,but it will cause the overgrowth of microcrystals;(2)It is not easy for AgNO3to produce Ag NPs,but introducing AgNO3can increase the content of Ag+ions.Therefore,co-doping AgCl and AgNO3can combine the characteristics of AgCl and AgNO3.Comparing to single doped AgCl or AgNO3,co-doping AgCl and AgNO3can bring more Ag NPs into the glass,and keep the glass transparent.Based on the above reasons,the glass with appropriate co-doping proportion of AgCl and AgNO3show an enhancement ofup-conversion emission intensity due to the formation of a lot of Ag NPs and a small amount of micro-crystals.

    3 Conclusions

    The role of micro-crystals and Ag NPs on the thermal,structural and spectroscopic properties of TWL-ErYb glasses have been studied in this paper.Micro-crystallization can improve the efficiency of luminescence emission.In the meantime,Ag NPs can also increase the strength of luminescence emission.The luminous efficiency of glasses can be further increased by introducing micro-crystals and Ag NPs at the same time.However,the excessive growth of micro-crystals will decrease the strength of luminescence emission.We find that co-doping AgCl and AgNO3can increase the precipitation of Ag NPs and reducetheovergrowth ofmicro-crystals.Besides,appropriate heattreatmenttemperature can also promote the precipitation of Ag NPs,and help to control the precipitation of micro-crystals.TWL-ErYb glasses with a lot of Ag NPs and a small amount of micro-crystals can further improve the up-conversion luminescence intensity due to the enhanced LSPR effect and a low phonon energy environment.

    Acknowledgements:The research is supported by theShanghaiScienceTechnologyCommittee (GrantNo.12nm0504700).

    :

    [1]Dousti M R,Sahar M R,Amjad R J,et al.J.Lumin.,2013,143:368-373

    [2]Rivera V A G,Ledemi Y,Osorio S P A,et al.J.Non-Cryst.Solids,2012,358:399-405

    [3]Culea E,Vida-Simiti I,Borodi G,et al.Ceram.Int.,2014,40:11001-11007

    [4]Tikhomirov V K,Rodríguez V D,Méndez-Ramos J,et al.Sol.Energy Mater.Sol.Cells,2012,100:209-215

    [5]Dousti M R,Amjad R J,Mahraz Z A S.J.Mol.Struct.,2015,1079:347-352

    [6]Qiu J B,Jiao Q,Zhou D C,et al.J.Rare Earths,2016,34:341-367

    [7]Gao Y,Hu Y B,Ren P,et al.J.Alloys Compd.,2016,667:297-301

    [8]Ansari G F,Mahajan S K.J.Lumin.,2014,156:97-101

    [9]de Araujo C B,da Silva D S,de Assumpcao T A A,et al.The Scientific World Journal,2013,2013:385193

    [10]Wu Y,Shen X,Dai S X,et al.J.Phys.Chem.C,2011,115:25040-25045

    [11]Chin P T,van der Linden M,van Harten E J,et al.Nanotechnology,2013,24:075703

    [12]Amjad R J,Sahar M R,Dousti M R,et al.Opt.Express,2013,21:14282-14290

    [13]Mertens H,Koenderink A F,Polman A.Phys.Rev.B,2007,76(11):115123

    [14]Chen S M,Qiu J B,Zhou D C,et al.Chin.Opt.Lett.,2014,12:081601-081604

    [15]Balaji S,Misra D,Debnath R.J.Fluoresc.,2011,21:1053-1060

    [16]XIAO Sheng-Chun(肖生春),Lü Jing-Wen (呂景文),ZHENG Tao(鄭濤)et al.Chinese Journal of Lasers(中國激光),2012,39(2):0206002

    [17]Rivera V A G,Osorio S P A,Manzani D,et al.Opt.Mater.,2011,33:888-892

    [18]Wei Y L,Li J J,Yang J W,et al.J.Lumin.,2013,137:70-72

    [19]Zhang Q Y,Feng Z M,Yang Z M,et al.J.Quant.Spectrosc.Radiat.Transfer,2006,98:167-179

    [20]Ma Y,Lin J,Chen J J,et al.Mater.Lett.,2011,65:282-284

    [21]Ghoshal S K,Awang A,Sahar M R,et al.J.Lumin.,2015,159:265-273

    [22]Reza Dousti M,Sahar M R,Ghoshal S K,et al.J.Mol.Struct.,2013,1035:6-12

    [23]Zhang W J,Lin J,Cheng M Z,et al.J.Quant.Spectrosc.Radiat.Transfer,2015,159:39-52

    [24]Lide D R.CRC Handbook of Chemistry and Physics.Boca Raton:CRC press,2004.

    [25]Mattarelli M,Montagna M,Vishnubhatla K,et al.Phys.Rev.B,2007,75(12):125102

    [26]Baida H,Marhaba S,et al.Nano Lett.,2009,9:3463-3469

    [27]Amjad R J,Sahar M R,Ghoshal S K,et al.J.Lumin.,2013,136:145-149

    [28]Hou Z X,Xue Z L,Li F,et al.J.Alloys Compd.,2013,577:523-527

    [29]JIA Yu-Jie(賈玉潔),LIN Jian(林?。?ZHANG Wen-Jun(張文?。?Chinese Journal of Luminescence(發(fā)光學報),2014,35:287-292

    [30]Ma R H,Qian J Y,Cui S,et al.J.Lumin.,2014,152:222-225

    [31]ZHANG Shuo(張碩),LIN Jian(林健),ZHANG Wen-Jun(張文?。?Chinese Journal of Luminescence(發(fā)光學報),2015,36:305-311

    [32]Ledemi Y,Trudel A A,Rivera V A G,et al.Optical Components and Materials XI,2014,8982:UNSP 89820V

    猜你喜歡
    微晶學報
    鋰鋁硅微晶玻璃不混溶及其析晶探討
    NASICON型微晶玻璃電解質(zhì)的研究現(xiàn)狀與展望
    陶瓷學報(2021年1期)2021-04-13 01:32:44
    致敬學報40年
    微晶剛玉磨粒磨削20CrMnTi鋼的數(shù)值模擬研究
    Li2O加入量對Li2O-Al2O3-SiO2微晶玻璃結(jié)合劑性能的影響
    學報簡介
    學報簡介
    水熱法制備NaSm(MoO4)2-x(WO4)x固溶體微晶及其發(fā)光性能
    《深空探測學報》
    微晶玻璃的制備、分類及應用評述
    河南科技(2014年16期)2014-02-27 14:13:13
    大型av网站在线播放| 亚洲av日韩精品久久久久久密| 91麻豆精品激情在线观看国产 | 欧美午夜高清在线| 精品福利永久在线观看| 精品午夜福利视频在线观看一区| 王馨瑶露胸无遮挡在线观看| 欧美亚洲日本最大视频资源| 欧美老熟妇乱子伦牲交| 在线观看午夜福利视频| 丰满人妻熟妇乱又伦精品不卡| 免费在线观看视频国产中文字幕亚洲| 精品久久久久久,| 亚洲熟妇熟女久久| 欧美成狂野欧美在线观看| 正在播放国产对白刺激| 精品少妇一区二区三区视频日本电影| 他把我摸到了高潮在线观看| 亚洲精华国产精华精| 中出人妻视频一区二区| 热99国产精品久久久久久7| 国产男靠女视频免费网站| 国产欧美亚洲国产| 无人区码免费观看不卡| 国产1区2区3区精品| 久久久久久免费高清国产稀缺| av视频免费观看在线观看| 免费人成视频x8x8入口观看| 日韩欧美在线二视频 | 欧美日韩成人在线一区二区| 伦理电影免费视频| 一级黄色大片毛片| 精品人妻在线不人妻| 狠狠狠狠99中文字幕| 亚洲免费av在线视频| 色综合婷婷激情| 精品电影一区二区在线| 国产精品一区二区在线观看99| 一级作爱视频免费观看| 男男h啪啪无遮挡| 12—13女人毛片做爰片一| 亚洲久久久国产精品| 又大又爽又粗| 精品少妇久久久久久888优播| 热re99久久精品国产66热6| 精品乱码久久久久久99久播| 亚洲熟女精品中文字幕| 久久国产亚洲av麻豆专区| 国产成人欧美| 久久久水蜜桃国产精品网| 免费观看a级毛片全部| 亚洲在线自拍视频| 老司机靠b影院| 亚洲男人天堂网一区| 视频在线观看一区二区三区| 成人影院久久| 国产一区二区三区视频了| 在线免费观看的www视频| 18在线观看网站| 欧美精品av麻豆av| 亚洲精品国产区一区二| 老汉色av国产亚洲站长工具| 免费在线观看亚洲国产| 欧美精品啪啪一区二区三区| 欧美精品高潮呻吟av久久| 欧美日韩乱码在线| 大码成人一级视频| 亚洲五月色婷婷综合| 少妇被粗大的猛进出69影院| 久久精品亚洲av国产电影网| 精品少妇久久久久久888优播| 免费在线观看影片大全网站| 成在线人永久免费视频| 亚洲精品乱久久久久久| 亚洲va日本ⅴa欧美va伊人久久| 在线观看一区二区三区激情| 亚洲五月天丁香| 免费av中文字幕在线| 久热爱精品视频在线9| 亚洲视频免费观看视频| 久久香蕉激情| 91九色精品人成在线观看| 村上凉子中文字幕在线| 欧美在线一区亚洲| 黑人欧美特级aaaaaa片| 亚洲专区中文字幕在线| 国内毛片毛片毛片毛片毛片| 国产单亲对白刺激| 一边摸一边做爽爽视频免费| 美女高潮到喷水免费观看| bbb黄色大片| 免费一级毛片在线播放高清视频 | 日本黄色视频三级网站网址 | 老司机深夜福利视频在线观看| 精品久久久久久,| 狠狠狠狠99中文字幕| 免费久久久久久久精品成人欧美视频| 亚洲精品国产区一区二| 欧美日韩亚洲综合一区二区三区_| 国产区一区二久久| 欧美精品亚洲一区二区| 一二三四社区在线视频社区8| 欧美人与性动交α欧美精品济南到| 怎么达到女性高潮| videos熟女内射| 性色av乱码一区二区三区2| 欧美成人免费av一区二区三区 | 男女之事视频高清在线观看| 正在播放国产对白刺激| 嫩草影视91久久| 成在线人永久免费视频| av网站在线播放免费| 一二三四在线观看免费中文在| 亚洲精品一二三| 欧美成狂野欧美在线观看| 免费一级毛片在线播放高清视频 | 纯流量卡能插随身wifi吗| 亚洲人成77777在线视频| 90打野战视频偷拍视频| 很黄的视频免费| 国产免费男女视频| 亚洲第一青青草原| 18禁黄网站禁片午夜丰满| 一区二区三区国产精品乱码| 精品一品国产午夜福利视频| 一区在线观看完整版| 在线观看免费高清a一片| 精品电影一区二区在线| 午夜亚洲福利在线播放| 国内久久婷婷六月综合欲色啪| 亚洲精品在线美女| 国产精品一区二区在线观看99| 久久精品国产99精品国产亚洲性色 | 99国产综合亚洲精品| 精品午夜福利视频在线观看一区| 身体一侧抽搐| 美女高潮到喷水免费观看| 亚洲一区高清亚洲精品| 亚洲国产欧美网| 不卡一级毛片| 成年人免费黄色播放视频| cao死你这个sao货| 精品一区二区三区av网在线观看| 精品亚洲成a人片在线观看| 国产成人精品无人区| 久久午夜综合久久蜜桃| 新久久久久国产一级毛片| 狠狠狠狠99中文字幕| 国产高清国产精品国产三级| 亚洲少妇的诱惑av| 一级片免费观看大全| 黄色a级毛片大全视频| 嫩草影视91久久| 亚洲aⅴ乱码一区二区在线播放 | 亚洲av成人不卡在线观看播放网| 日本a在线网址| 男女高潮啪啪啪动态图| 老熟女久久久| 母亲3免费完整高清在线观看| 亚洲情色 制服丝袜| 大型黄色视频在线免费观看| 麻豆av在线久日| 啦啦啦视频在线资源免费观看| 亚洲成人免费av在线播放| 亚洲av欧美aⅴ国产| 高潮久久久久久久久久久不卡| www.自偷自拍.com| 夜夜爽天天搞| 精品卡一卡二卡四卡免费| 美女午夜性视频免费| 国产精华一区二区三区| 热99国产精品久久久久久7| 午夜免费观看网址| 最新在线观看一区二区三区| 精品福利观看| 国产一区二区三区在线臀色熟女 | 麻豆成人av在线观看| 国产精品.久久久| 欧美成人免费av一区二区三区 | 亚洲五月天丁香| 一级毛片精品| 另类亚洲欧美激情| 夜夜夜夜夜久久久久| 一级黄色大片毛片| 午夜亚洲福利在线播放| 一级毛片精品| 精品视频人人做人人爽| 亚洲人成伊人成综合网2020| 精品国产亚洲在线| 天堂中文最新版在线下载| 亚洲情色 制服丝袜| av中文乱码字幕在线| 夜夜爽天天搞| 亚洲专区字幕在线| 1024香蕉在线观看| av片东京热男人的天堂| 每晚都被弄得嗷嗷叫到高潮| 一边摸一边抽搐一进一小说 | 69av精品久久久久久| 久久青草综合色| 欧美av亚洲av综合av国产av| 18禁黄网站禁片午夜丰满| 欧美日韩av久久| 国产欧美亚洲国产| 91大片在线观看| 99久久人妻综合| 一级,二级,三级黄色视频| 中文字幕高清在线视频| 99热只有精品国产| 成熟少妇高潮喷水视频| 人人妻,人人澡人人爽秒播| 久久久久国内视频| 欧美国产精品va在线观看不卡| 免费在线观看完整版高清| 操美女的视频在线观看| 欧美日韩亚洲高清精品| 18禁裸乳无遮挡免费网站照片 | 人妻一区二区av| e午夜精品久久久久久久| 麻豆成人av在线观看| 国产一区二区三区在线臀色熟女 | 国产无遮挡羞羞视频在线观看| 免费女性裸体啪啪无遮挡网站| 丰满迷人的少妇在线观看| 女人高潮潮喷娇喘18禁视频| 后天国语完整版免费观看| 免费日韩欧美在线观看| 中文字幕人妻丝袜一区二区| 人妻久久中文字幕网| 午夜视频精品福利| 日韩大码丰满熟妇| 成年版毛片免费区| 午夜亚洲福利在线播放| 免费观看精品视频网站| 日韩欧美一区二区三区在线观看 | 欧美 日韩 精品 国产| 亚洲av欧美aⅴ国产| 色播在线永久视频| 热99久久久久精品小说推荐| 亚洲综合色网址| 天天躁夜夜躁狠狠躁躁| 青草久久国产| 国产精品98久久久久久宅男小说| 国内毛片毛片毛片毛片毛片| 一级毛片高清免费大全| 亚洲av成人av| 久久久久精品国产欧美久久久| 亚洲伊人色综图| 18禁裸乳无遮挡免费网站照片 | 久久国产精品大桥未久av| 最新美女视频免费是黄的| 在线视频色国产色| 久久久精品国产亚洲av高清涩受| 女人被躁到高潮嗷嗷叫费观| 十八禁人妻一区二区| 搡老熟女国产l中国老女人| 亚洲久久久国产精品| 国产精品久久电影中文字幕 | 成人黄色视频免费在线看| 老司机在亚洲福利影院| 少妇裸体淫交视频免费看高清 | 欧美乱码精品一区二区三区| 亚洲av成人av| 黄片播放在线免费| 精品人妻在线不人妻| 两人在一起打扑克的视频| 久久久久久免费高清国产稀缺| 交换朋友夫妻互换小说| 757午夜福利合集在线观看| 亚洲av美国av| 高清在线国产一区| 亚洲国产看品久久| 国产单亲对白刺激| 伊人久久大香线蕉亚洲五| 日韩大码丰满熟妇| 少妇 在线观看| 日本a在线网址| 美女福利国产在线| 久久香蕉国产精品| 午夜免费鲁丝| 亚洲久久久国产精品| 黑人猛操日本美女一级片| 自线自在国产av| 一区二区三区精品91| 9热在线视频观看99| 黄色视频,在线免费观看| 免费在线观看日本一区| 人人妻人人爽人人添夜夜欢视频| 美女扒开内裤让男人捅视频| 国产又色又爽无遮挡免费看| 91麻豆av在线| 啦啦啦免费观看视频1| 久久久精品国产亚洲av高清涩受| 91字幕亚洲| 久久午夜亚洲精品久久| 精品国产亚洲在线| 久久性视频一级片| 一区二区三区激情视频| 亚洲五月婷婷丁香| 精品少妇一区二区三区视频日本电影| 久久精品91无色码中文字幕| 黄色成人免费大全| 国产精品久久视频播放| 一级a爱视频在线免费观看| 久久人妻熟女aⅴ| 一级毛片高清免费大全| 女性生殖器流出的白浆| 美女福利国产在线| 在线天堂中文资源库| 国产精品一区二区在线不卡| 国产不卡av网站在线观看| 国产激情久久老熟女| 色在线成人网| 国产亚洲欧美98| 精品电影一区二区在线| bbb黄色大片| 飞空精品影院首页| 一区在线观看完整版| 亚洲三区欧美一区| a在线观看视频网站| 欧美激情久久久久久爽电影 | 视频区欧美日本亚洲| 免费观看精品视频网站| 日韩三级视频一区二区三区| 一级毛片精品| 久久久久久久午夜电影 | 18禁观看日本| 精品熟女少妇八av免费久了| 久久久久久人人人人人| 一级作爱视频免费观看| 亚洲专区国产一区二区| 18在线观看网站| 亚洲专区国产一区二区| 丝袜人妻中文字幕| 一边摸一边做爽爽视频免费| 大香蕉久久成人网| 精品国产超薄肉色丝袜足j| 在线观看午夜福利视频| 亚洲色图av天堂| 91av网站免费观看| 日日爽夜夜爽网站| 亚洲av日韩精品久久久久久密| 精品国产乱子伦一区二区三区| 久久天堂一区二区三区四区| 久久国产精品人妻蜜桃| 国产精品二区激情视频| 国产精品电影一区二区三区 | av电影中文网址| 国产精品自产拍在线观看55亚洲 | cao死你这个sao货| 黄色成人免费大全| 亚洲人成电影观看| 黄网站色视频无遮挡免费观看| 视频在线观看一区二区三区| 日韩中文字幕欧美一区二区| tocl精华| 欧美日韩亚洲高清精品| 无人区码免费观看不卡| videos熟女内射| av片东京热男人的天堂| 欧美精品高潮呻吟av久久| 亚洲成国产人片在线观看| 久久久国产欧美日韩av| 亚洲精品乱久久久久久| 国产又色又爽无遮挡免费看| 色尼玛亚洲综合影院| 久热这里只有精品99| 一级片'在线观看视频| 国产一区有黄有色的免费视频| 国产熟女午夜一区二区三区| 纯流量卡能插随身wifi吗| 免费观看a级毛片全部| 国产无遮挡羞羞视频在线观看| 欧美乱妇无乱码| 精品国产超薄肉色丝袜足j| 国产色视频综合| 999久久久精品免费观看国产| 国产色视频综合| 欧美日韩黄片免| 大香蕉久久成人网| 久久久久久人人人人人| 亚洲欧美激情综合另类| 丁香欧美五月| 法律面前人人平等表现在哪些方面| 久久狼人影院| 男女高潮啪啪啪动态图| 99精品欧美一区二区三区四区| 人人澡人人妻人| 一本一本久久a久久精品综合妖精| 最近最新中文字幕大全电影3 | 丰满人妻熟妇乱又伦精品不卡| 在线永久观看黄色视频| 久久人人爽av亚洲精品天堂| 岛国毛片在线播放| 看片在线看免费视频| 女人久久www免费人成看片| 精品高清国产在线一区| 少妇裸体淫交视频免费看高清 | 悠悠久久av| 中文字幕人妻熟女乱码| 女人高潮潮喷娇喘18禁视频| 人妻久久中文字幕网| 一区二区日韩欧美中文字幕| 久久影院123| www.999成人在线观看| 亚洲欧美日韩高清在线视频| 国产成人精品在线电影| 国产在视频线精品| 亚洲一码二码三码区别大吗| 国产精品98久久久久久宅男小说| 青草久久国产| www.自偷自拍.com| 久久草成人影院| 精品视频人人做人人爽| 两个人看的免费小视频| 日韩熟女老妇一区二区性免费视频| 99久久99久久久精品蜜桃| 少妇裸体淫交视频免费看高清 | 国产欧美日韩一区二区三区在线| aaaaa片日本免费| 免费看a级黄色片| 成年女人毛片免费观看观看9 | 日本撒尿小便嘘嘘汇集6| 91成人精品电影| 久久久久视频综合| 一进一出好大好爽视频| 精品一区二区三区av网在线观看| 色94色欧美一区二区| 在线观看舔阴道视频| 天堂中文最新版在线下载| 国产乱人伦免费视频| 超色免费av| 欧美 日韩 精品 国产| 亚洲人成伊人成综合网2020| 美女午夜性视频免费| 高清在线国产一区| 在线天堂中文资源库| 亚洲欧美一区二区三区久久| 亚洲av熟女| 精品少妇一区二区三区视频日本电影| 99精品久久久久人妻精品| 十八禁高潮呻吟视频| 在线av久久热| 国产精品国产av在线观看| 亚洲欧美日韩高清在线视频| 成在线人永久免费视频| 午夜激情av网站| 欧美精品人与动牲交sv欧美| 成人18禁高潮啪啪吃奶动态图| 91麻豆精品激情在线观看国产 | 亚洲全国av大片| 国产区一区二久久| 国产精品久久久人人做人人爽| 久久人人爽av亚洲精品天堂| 亚洲人成77777在线视频| 免费日韩欧美在线观看| 国产无遮挡羞羞视频在线观看| 在线观看日韩欧美| tube8黄色片| 欧美国产精品一级二级三级| 日本黄色日本黄色录像| 香蕉久久夜色| 亚洲一区二区三区欧美精品| 纯流量卡能插随身wifi吗| 亚洲一区高清亚洲精品| 亚洲视频免费观看视频| 男男h啪啪无遮挡| 亚洲国产精品一区二区三区在线| 国产亚洲一区二区精品| 欧美人与性动交α欧美精品济南到| 婷婷精品国产亚洲av在线 | 80岁老熟妇乱子伦牲交| 亚洲精品久久午夜乱码| 香蕉丝袜av| 老司机在亚洲福利影院| 午夜精品久久久久久毛片777| www.自偷自拍.com| 国产精品免费大片| 亚洲av成人av| 老司机深夜福利视频在线观看| 中国美女看黄片| 老熟妇仑乱视频hdxx| 女人被狂操c到高潮| 丰满的人妻完整版| 男男h啪啪无遮挡| 国产成人精品无人区| 热re99久久精品国产66热6| x7x7x7水蜜桃| 人妻 亚洲 视频| 99精品在免费线老司机午夜| 日韩欧美免费精品| 一级黄色大片毛片| 国产精品秋霞免费鲁丝片| av在线播放免费不卡| 黑人欧美特级aaaaaa片| 欧美日韩亚洲综合一区二区三区_| 国产精品免费视频内射| 国产精品美女特级片免费视频播放器 | 好看av亚洲va欧美ⅴa在| 母亲3免费完整高清在线观看| 久久婷婷成人综合色麻豆| 成人国语在线视频| a级片在线免费高清观看视频| 看片在线看免费视频| 国产成人精品久久二区二区91| 中文亚洲av片在线观看爽 | 黄色女人牲交| 国产成人精品久久二区二区免费| 一级片免费观看大全| ponron亚洲| 大片电影免费在线观看免费| 亚洲精品美女久久av网站| 高清欧美精品videossex| 欧美亚洲 丝袜 人妻 在线| 亚洲 国产 在线| 成熟少妇高潮喷水视频| 日韩三级视频一区二区三区| 亚洲一区中文字幕在线| 欧美日韩一级在线毛片| 成年动漫av网址| 亚洲欧美日韩高清在线视频| 亚洲精品中文字幕一二三四区| 国产无遮挡羞羞视频在线观看| 女人被狂操c到高潮| 日韩欧美三级三区| 好看av亚洲va欧美ⅴa在| 国产成人影院久久av| 亚洲 国产 在线| 法律面前人人平等表现在哪些方面| 国产精品九九99| 欧美激情久久久久久爽电影 | 一区二区三区精品91| 涩涩av久久男人的天堂| 欧美久久黑人一区二区| 91av网站免费观看| 亚洲精品国产区一区二| 欧美成人免费av一区二区三区 | 成人18禁高潮啪啪吃奶动态图| 大陆偷拍与自拍| 亚洲欧美激情在线| 十分钟在线观看高清视频www| 黄片小视频在线播放| 天天躁日日躁夜夜躁夜夜| 超色免费av| 村上凉子中文字幕在线| 精品一区二区三区av网在线观看| 亚洲欧美一区二区三区黑人| 国产精品久久久久久精品古装| 久久久久国产一级毛片高清牌| 久久久久精品人妻al黑| 激情在线观看视频在线高清 | 国产一区在线观看成人免费| 久久青草综合色| 亚洲av欧美aⅴ国产| 欧美+亚洲+日韩+国产| 午夜成年电影在线免费观看| 国产精品.久久久| 亚洲专区国产一区二区| 国产成人免费观看mmmm| 欧美激情 高清一区二区三区| 无限看片的www在线观看| 欧美日韩视频精品一区| 精品国产一区二区三区四区第35| 国精品久久久久久国模美| 亚洲国产欧美一区二区综合| 99国产极品粉嫩在线观看| 国产日韩一区二区三区精品不卡| 精品国产乱码久久久久久男人| 不卡一级毛片| 美女扒开内裤让男人捅视频| 一个人免费在线观看的高清视频| 亚洲熟女毛片儿| 久久精品国产99精品国产亚洲性色 | 咕卡用的链子| 久久午夜亚洲精品久久| 久久精品熟女亚洲av麻豆精品| 中文字幕av电影在线播放| 老鸭窝网址在线观看| 精品人妻1区二区| 精品久久久久久久久久免费视频 | 制服诱惑二区| 国产主播在线观看一区二区| 久久精品国产综合久久久| 欧美亚洲 丝袜 人妻 在线| 在线观看一区二区三区激情| 啦啦啦视频在线资源免费观看| 久久精品成人免费网站| 亚洲成人免费av在线播放| 免费在线观看日本一区| 色精品久久人妻99蜜桃| 国产男靠女视频免费网站| 人人妻人人添人人爽欧美一区卜| 亚洲国产精品一区二区三区在线| 自线自在国产av| 两个人看的免费小视频| cao死你这个sao货| 十八禁高潮呻吟视频| 高潮久久久久久久久久久不卡| 久久久久久久久久久久大奶| 男女午夜视频在线观看| 亚洲 欧美一区二区三区| 亚洲一区二区三区欧美精品| 天天躁狠狠躁夜夜躁狠狠躁| 啦啦啦视频在线资源免费观看| 日韩大码丰满熟妇| 99re在线观看精品视频| 国产成人精品久久二区二区免费| 久久性视频一级片| 国产主播在线观看一区二区| av电影中文网址| 国产欧美日韩综合在线一区二区| 18禁国产床啪视频网站| 色老头精品视频在线观看| 美女 人体艺术 gogo| 黄片小视频在线播放|