• <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 ?

    Crystal structure and proton-conductivity of a complex based on phosphomolybdic acid and 2-(2-h(huán)ydroxybenzene)benzimidazole

    2014-03-07 03:49:00CHENLinWEIMeilin
    化學(xué)研究 2014年5期
    關(guān)鍵詞:苯并咪唑鉬酸化工學(xué)院

    CHEN Lin,WEI Meilin

    (SchoolofChemistryandChemicalEngineering,HenanNormalUniversity,Xinxiang453007,Henan,China)

    Crystal structure and proton-conductivity of a complex based on phosphomolybdic acid and 2-(2-h(huán)ydroxybenzene)benzimidazole

    CHEN Lin,WEI Meilin*

    (SchoolofChemistryandChemicalEngineering,HenanNormalUniversity,Xinxiang453007,Henan,China)

    A proton-conductive organic-inorganic complex,[H3L2(PMo12O40)·7H2O·4CH3OH]n(1),was constructed with phosphomolybdic acid and 2-(2-h(huán)ydroxybenzene)benzimidazole(L)as the starting materials.Single-crystal X-ray diffraction analysis reveals that complex 1 exhibits a two-dimensional hydrogen-bonding network structure based-on phosphomolybdic acid,L molecules and solvent methanol molecules.Besides,complex 1 shows proton conductivity of about 10-4S·cm-1at 100℃under 98%relative humidity.

    phosphomolybdic acid;benzimidazole;organic-inorganic complex;crystal structure;proton conductivity

    Solid-state materials with proton conductivities have interested us from the point of view of transport dynamics and their applications in fuel cells[1-6].Supramolecular assemblies built by means of hydrogenbonding interactions have provided numerous solid-state materials with very attractive properties.For a long time,we have focused on organic/inorganic complexes based-on Keggin-type heteropolyacids dispersing in self-ordered hydrogen-bonded networks from the ligands containing 2-substituted benzimidazoles such as 2-(3-pyridyl)benzimidazole molecules[4],which have attracted considerable interest for their versatile coordination modes and potential to form supramolecular aggregates throughπ-πstacking and hydrogen bonding interactions[4,7].In the present research,by a self-assembly of phosphomolybdic acid and 2-(2-h(huán)ydroxybenzene)benzimidazole molecules(L),we have constructed a proton-conductive organic/inorganic hybrid complex,[H3L2(PMo12O40)·7H2O·4CH3OH]n(1).X-ray diffraction analyses at 293Krevealed that complex 1 presented a two-dimensional(2D)supramolecular framework constructed by L molecules,phosphomolybdic acid and methanol molecules based-on hydrogen-bonding interactions.The results of the impedance measurement show that complex 1is a good proton conductor.Interestingly,complex 1 shows proton conductivities across a wide range of temperatures and relative humidity(RH)and achieve proton conductivity over~10-4S·cm-1at 100℃under 98%RH.Here we report the synthesis and structural characterization of complex 1 as well as its proton conductivity evaluation in relation to temperature and RH.

    1 Experimental

    1.1 Materials and instruments

    All organic solvents and materials used for synthesis were of reagent grade and used without further purification.α-H3PMo12O40·6H2O was also prepared according to a literature method[1-4]and characterized by IR spectrum and TG analysis.L was prepared according to a literature method[8].Elemental analyses(C,H,and N)were carried out on a Perkin-Elmer 240Canalyzer.X-ray powder diffraction(XRD)was performed on a Bruker D8Advance Instrument using Cu-Kαradiation and a fixed power source(40 kV,40mA).IR spectrum was recorded on a VECTOR 22Bruker spectrophotometer with KBr pellets in the 400-4 000cm-1region at room temperature.Thermogravimetric analysis and differential scanning calorimetry were performed on a Perkin-Elmer thermal analyzer under nitrogen at a heating rate of 10℃· min-1.For an electrical conductivity study,the powdered crystalline samples were compressed to 1.0-1.2 mm in thickness and 12.0mm in diameter under a pressure of 12-14MPa.Alternating current(Ac)impedance spectroscopy measurement was performed on a chi660d(Shanghai Chenhua)electrochemical impedance analyzer with copper electrodes[1-6](the purity of Cu is more than 99.8%;the pellet was contacted with two copper plates)over the frequency range from 105Hz to 10Hz.The conductivity was calculated asσ=(1/R)×(h/S),whereRis the resistance,his the thickness,andSis the area of the tablet.

    1.2 Synthesis of the title compound

    Complex 1 was prepared by layering method.A buffer layer of a solution(10mL)of methanol-water(1∶1,V/V)was carefully layered over 5mL of an aqueous solution ofα-H3PMo12O40·6H2O(120mg,0.06mmol).Then a methanol(5mL)of L(25.2mg,0.12mmol)was carefully layered over the buffer layer.Two weeks later,red crystals appeared and were collected and dried in air after quickly being washed with water.Yield:91mg,76%based onα-H3PMo12O40·6H2O.Anal.Calcd(%)for C30H53Mo12N4O53P:calcd(%):C,14.41;H,2.14;N,2.24;Found(%):C,14.33;H,2.07;N,2.16.IR(KBr,cm-1):four characteristic vibrations resulting from heteropolyanions with the Keggin structure:809ν(Mo-Oc),881ν(Mo-Ob),955ν(Mo=Ot),1 068ν(P-Oa);some vibrations resulting from L molecules:3 270ν(O-H),1 625ν(C=N),1 245ν(C-O),1 062ν(C-C).

    1.3 Structure determination

    Intensity data of complex 1 were collected on a Siemens SMART CCD diffractometer with graphitemonochromated Cu-Kαradiation(λ=0.071 073nm)using SMART and SAINT.The structure was solved by direct methods and refined onF2by using full-matrix least-squares method with SHELXTL version 5.1[9].All non-h(huán)ydrogen atoms except for solvent molecules were refined anisotropically.Hydrogen atoms of organic molecules were localized in their calculated positions and refined using a riding model.Hydrogen atoms of solvent water molecules were not treated.The crystal parameters,data collection and refinement results for complex1 are summarized in Table 1,and the selected hydrogen bond parameters in Table 2with the lables of atoms shown in Fig.1.CCDC contains the supplementary crystallographic data for this paper.These data can be obtained free of charge from the Cambridge Crystallographic Data Centreviahttp://www.ccdc.cam.ac.uk/data_request/cif.

    Table 1 Crystallographic data and refinement parameters for the title complex

    Fig.1 Molecular structure unit of complex 1showing the labeling atoms at 30% probability thermal ellipsoids and hydrogen-bonding interactions(solvent water molecules and hydrogen atoms have been omitted for clarity)

    Table 2 Hydrogen bond lengths(nm)and bond angles(°)

    2 Results and discussion

    2.1 Structure description

    Complex 1,[H3(PMo12O40)L2·7H2O·4CH3OH]n,was synthesized by the reaction of phosphomolybdic acid and L molecules at room temperature.It was characterized by single-crystal X-ray diffraction,infrared spectroscopy,TG and elemental analyses.X-ray diffraction analyses at 293Krevealed that complex 1 crystallized in the triclinic space groupPīand presented a 2Dsupramolecular framework constructed by L molecules,phosphomolybdic acid and methanol molecules based-on hydrogen-bonding interactions.The molecular structure of 1is shown in Fig.1.The molecular unit contains two L molecules,one phosphomolybdic acid molecule,four methanol molecules and seven water molecules.In the L molecule,the dihedral angle between the benzimidazole ring and the benzene ring of 2-h(huán)ydroxybenzene is 6.26°.Bond valence sum(BVS)calculations[10]indicate that the N2atom of the imidazole ring is the possible binding site of a proton from phosphomolybdic acid.Based on hydrogen-bonding interactions,two L molecules,one phosphomolybdic acid molecule and four methanol molecules form a cluster,[(H3PMo12O40)L2(CH3OH)4].Moreover,the clusters are connected with each other based-on the hydrogen-bonded interactions between the O7atoms of[PMo12O40]3-anions and the O24atoms of methanol molecules to form a 2Dlayer structure with voids(Fig.2).Solvent water molecules were just embedded in the voids.In addition,the presence of positively species,H+,from phosphomolybdic acid being embedded in the voids of the 2Danionic framework,could not only attract the polyanions to stabilize the 2Dsupramolecular framework,but also provide potential proton carriers.

    In the[PMo12O40]3-anion,the bond lengths of P-O and Mo-O are 1.480(8)-1.603(9)and 0.163 7(6)-0.248 1(9)nm,respectively.The bond lengths of P-O and Mo-O are respectively comparable to those in the polyoxometalates-based organic-inorganic hybrid materials with Keggin anions as guests.In addition,the O-P-O angles are in the range of 66.7(5)°-112.2(4)°.All these results indicate that the[PMo12O40]3-units have a normal Keggin structure[1-4].

    Therefore,in complex1,based on electrostatic and hydrogen-bonding interactions,[PMo12O40]3-anions were stabilized in the supramolecular framework and not easily dissociated from the hybrid network.In addition,the protons from Keggin-type heteropolyacids,the protons belong to L molecules and hydrogen bonding networks indicate that complex 1 can potentially be a good proton-conducting material.

    Fig.2 The 2Dhydrogen-bonded network in complex 1down the baxis

    Fig.3 The curve of the Perkin-Elmer thermal analysis of complex 1in the atmosphere of N2

    2.2 TG analysis

    Fig.3shows the TG result for complex1.Thermal analysis of the powder of the crystalline sample of complex 1in an atmosphere of N2reveals that the robustness of the porous network could retain up to 300℃with a weight loss of about 4.91%in the temperature range 20-110℃(the weight loss corresponds to the loss of all solvent water molecules).The robustness of the porous network begins to decompose above 300℃due to the loss of methanol molecules and L molecules,indicating that methanol molecules and L molecules in the unit structure are involved in hydrogen-bonding interactions with the supramolecular framework,which is consistent with the result of structural analysis,and could be hold in the supramolecular framework at 300℃.

    2.3 Proton conductivity

    The proton conductivity of complex 1 was measured at 25℃in the RH range 35%-98%by a complex-plane impedance method using a compacted pellet of the powdered crystalline sample,which has the same structure as the single-crystal.At 25℃,complex1 showed poor proton conductivities of~10S· cm-1under 35%RH conditions,and its proton conductivities reached~6.5×10-8S·cm-1with RH up to 98%.The proton conductivities of 1 were also measured at 100℃in the RH range 35%-98%by a complex-plane impedance method.Fig.4shows the lg[σ/(S·cm-1)]versus RH plots of complex1 at 25and 100℃under 35%-98%RH.The conductivities of complex 1 increase with increasing RH at both temperatures.Again,we measured its ionic conductivities up to 100℃under 98%RH conditions.As the temperature increases,the proton conductivities of complex 1increase on a logarithmic scale even with almost saturated humidities.Fig.5shows the Arrhenius plots of the proton conductivities of complex 1 in the temperature range of 25-100℃under 98%RH conditions.The ln(σT)increases almost linearly with temperature range from 25to 100℃,and the corresponding activation energy(Ea)of conductivity was estimated to be 1.25eV.TheEavalue is high in the temperature range of 25-100℃.This is probably due to the fact that protons originating from phosphomolybdic acid and those originating from L molecules need a endothermal process for dissociation as hydrated forms such as H+,H3O+or other proton species[1-4].Therefore,the fact that complex1 exhibits good proton conductivities(5.21×10-5-2.21×10-4S·cm-1)in the temperature range of 85-100℃is indicative of a high carrier concentration based on the dissociating processes of proton from L molecules and phosphomolybdic acid.The powder X-ray diffraction data suggest that the powder sample after the proton-conductive measurement has the same supramolecular framework as that of complex 1.

    Fig.4 Relative humidity dependence of the proton conductivity of complex 1

    Fig.5 Arrhenius plots of the proton conductivity of complex 1

    3 Conclusion

    In summary,aproton-conductive organic-inorganic complex based on phosphomolybdic acid and 2-(2-h(huán)ydroxybenzene)benzimidazole molecules has been constructed.The organic-inorganic hybrid matrix changed the environment around phosphomolybdic acid and influenced the formation of self-ordered hydrogen-bonding network within the resultant structure.Thus,complex 1 provides a route in increasing the stability and proton conductivity of organic-inorganic hybrid materials based on Keggin-type heteropolyacids and 2-(2-h(huán)ydroxybenzene)benzimidazole molecules up to 100℃.

    [1]WEI Meilin,ZHUANG Pengfei,LI Huihua,et al.Crystal structures and conductivities of two organic-inorganic hybrid complexes based on poly-Keggin-anion chains[J].Eur J Inorg Chem,2011(9):1473-1478.

    [2]WEI Meilin,ZHUANG Pengfei,MIAO Qiuxiang,et al.Two highly proton-conductive molecular hybrids based on ionized water clusters and poly-Keggin-anion chains[J].Solid State Chem,2011,184:1472-1477.

    [3]WEI Meilin,WANG Xiaoxiang,DUAN Xianying.Crystal structures and proton conductivities of a MOF and two POMMOF composites based on CuIIions and 2,2′-bipyridyl-3,3′-dicarboxylic acid[J].Chem Eur J,2013,19(5):1607-1616.

    基于磷鉬酸和2-(2-羥基苯)苯并咪唑復(fù)合物的晶體結(jié)構(gòu)和質(zhì)子導(dǎo)電性

    陳 林,魏梅林*
    (河南師范大學(xué)化學(xué)化工學(xué)院,河南新鄉(xiāng) 453007)

    以磷鉬酸和2-(2-羥基苯)苯并咪唑(L)為原料制備了具有質(zhì)子導(dǎo)電性的有機(jī)-無(wú)機(jī)化合物[H3L2(PMo12O40)·7H2O·4CH3OH]n(1).單晶X射線衍射分析結(jié)果表明化合物1具有基于磷鉬酸、2-(2-羥基苯)苯并咪唑及溶劑甲醇分子的二維氫鍵網(wǎng)絡(luò)結(jié)構(gòu);質(zhì)子導(dǎo)電性能測(cè)試結(jié)果表明該化合物在100℃、相對(duì)濕度為98%時(shí)的電導(dǎo)率達(dá)到10-4S·cm-1.

    磷鉬酸;苯并咪唑;有機(jī)-無(wú)機(jī)化合物;晶體結(jié)構(gòu);質(zhì)子導(dǎo)電性

    O 611

    A

    1008-1011(2014)05-0461-05

    10.14002/j.hxya.2014.05.006

    date:2014-03-11.

    National Natural Science Foundation of China(21171050).

    Biography:CHEN Lin(1989-),male,postgraduate,majoring in functional coordination compounds.*

    ,E-mail:weimeilinhd@163.com.

    猜你喜歡
    苯并咪唑鉬酸化工學(xué)院
    使固態(tài)化學(xué)反應(yīng)100%完成的方法
    專利名稱:一種硫摻雜鉬酸鉍納米片狀可見(jiàn)光催化劑的制備方法
    國(guó)家開(kāi)放大學(xué)石油和化工學(xué)院學(xué)習(xí)中心列表
    【鏈接】國(guó)家開(kāi)放大學(xué)石油和化工學(xué)院學(xué)習(xí)中心(第四批)名單
    鉬酸鹽與硅酸鹽復(fù)合鈍化膜耐蝕性的研究
    一種鉬酸鋰的制備方法
    芬頓氧化處理苯并咪唑類合成廢水實(shí)驗(yàn)研究
    《化工學(xué)報(bào)》贊助單位
    1,1-二(苯并咪唑-2-基)-2-(喹喔啉-2-基)乙烯的合成及其性能
    高性能鉬酸鋅/堿式鉬酸鋅微粉合成研究*
    午夜福利影视在线免费观看| 国产一卡二卡三卡精品| 欧美老熟妇乱子伦牲交| 久久精品国产亚洲av高清一级| 日韩人妻精品一区2区三区| 久9热在线精品视频| 国产人伦9x9x在线观看| 日日爽夜夜爽网站| 丝瓜视频免费看黄片| 精品少妇黑人巨大在线播放| 91精品三级在线观看| 久久亚洲国产成人精品v| 日本黄色日本黄色录像| 精品福利永久在线观看| 日本猛色少妇xxxxx猛交久久| 欧美人与性动交α欧美软件| 美女午夜性视频免费| 亚洲av电影在线进入| 99精品久久久久人妻精品| 国产人伦9x9x在线观看| 国产在视频线精品| 新久久久久国产一级毛片| 女人久久www免费人成看片| 免费人妻精品一区二区三区视频| 欧美久久黑人一区二区| 高潮久久久久久久久久久不卡| 国产日韩欧美视频二区| 在线永久观看黄色视频| 日本av免费视频播放| 青春草亚洲视频在线观看| 精品福利观看| 国产91精品成人一区二区三区 | 国产成人免费观看mmmm| 国产精品久久久久成人av| 亚洲伊人色综图| av有码第一页| 日本撒尿小便嘘嘘汇集6| 美女福利国产在线| 极品少妇高潮喷水抽搐| 在线看a的网站| 日韩中文字幕视频在线看片| 亚洲va日本ⅴa欧美va伊人久久 | 国产区一区二久久| 五月天丁香电影| 日本欧美视频一区| 国产精品久久久久久人妻精品电影 | 亚洲欧美成人综合另类久久久| 亚洲精品久久午夜乱码| 自线自在国产av| 欧美日韩中文字幕国产精品一区二区三区 | 伊人亚洲综合成人网| 国产亚洲欧美精品永久| 亚洲精品第二区| 久久久精品免费免费高清| 美女大奶头黄色视频| 2018国产大陆天天弄谢| 天堂俺去俺来也www色官网| 欧美老熟妇乱子伦牲交| 国产极品粉嫩免费观看在线| av电影中文网址| 在线观看人妻少妇| 国产福利在线免费观看视频| 搡老乐熟女国产| 国产日韩欧美视频二区| av有码第一页| 日本撒尿小便嘘嘘汇集6| 午夜福利影视在线免费观看| 国产一区有黄有色的免费视频| 老司机影院毛片| 国产一区二区在线观看av| netflix在线观看网站| 精品人妻1区二区| 久久中文字幕一级| 国产成人啪精品午夜网站| 丝袜脚勾引网站| 久久久精品免费免费高清| 国产黄色免费在线视频| 人人澡人人妻人| 亚洲精品成人av观看孕妇| 国产一区有黄有色的免费视频| 老汉色av国产亚洲站长工具| 少妇裸体淫交视频免费看高清 | tube8黄色片| 精品一区二区三卡| 十八禁网站网址无遮挡| 久久中文字幕一级| 国产黄色免费在线视频| 日本撒尿小便嘘嘘汇集6| 高清在线国产一区| 99久久精品国产亚洲精品| 日韩中文字幕视频在线看片| 久久这里只有精品19| 黑人猛操日本美女一级片| 91精品伊人久久大香线蕉| 国产亚洲精品一区二区www | 女警被强在线播放| 中文字幕色久视频| 亚洲情色 制服丝袜| 国产成人精品久久二区二区免费| 久热爱精品视频在线9| 亚洲伊人色综图| 久久国产精品男人的天堂亚洲| 精品乱码久久久久久99久播| 欧美日韩亚洲综合一区二区三区_| 99热网站在线观看| 男人爽女人下面视频在线观看| 国产主播在线观看一区二区| 免费人妻精品一区二区三区视频| 9191精品国产免费久久| 亚洲国产看品久久| 亚洲美女黄色视频免费看| 欧美大码av| 97人妻天天添夜夜摸| 亚洲伊人色综图| 99国产精品免费福利视频| 亚洲人成电影观看| 国产99久久九九免费精品| 好男人电影高清在线观看| 亚洲性夜色夜夜综合| 大码成人一级视频| 欧美日韩黄片免| 性高湖久久久久久久久免费观看| av又黄又爽大尺度在线免费看| 中文字幕精品免费在线观看视频| av线在线观看网站| 高清视频免费观看一区二区| 欧美xxⅹ黑人| 国产精品一区二区免费欧美 | 亚洲第一欧美日韩一区二区三区 | 999久久久国产精品视频| 亚洲人成77777在线视频| 久久久久视频综合| 妹子高潮喷水视频| 国产伦人伦偷精品视频| 精品一区二区三区av网在线观看 | 亚洲国产看品久久| 热re99久久国产66热| 老熟女久久久| 中国美女看黄片| 精品国产乱子伦一区二区三区 | 法律面前人人平等表现在哪些方面 | 中文字幕另类日韩欧美亚洲嫩草| 制服人妻中文乱码| 新久久久久国产一级毛片| 久久精品国产亚洲av高清一级| 亚洲精品国产色婷婷电影| 黄色 视频免费看| 成在线人永久免费视频| 欧美另类一区| 日本五十路高清| 精品福利永久在线观看| www.熟女人妻精品国产| 少妇粗大呻吟视频| 亚洲欧美精品自产自拍| 啦啦啦中文免费视频观看日本| 精品人妻一区二区三区麻豆| 免费人妻精品一区二区三区视频| 黄色毛片三级朝国网站| 人妻 亚洲 视频| 国产av又大| 国产免费一区二区三区四区乱码| 欧美精品高潮呻吟av久久| 老司机影院毛片| 国产欧美日韩一区二区精品| 久久久久精品国产欧美久久久 | 成人国产一区最新在线观看| 在线永久观看黄色视频| 亚洲国产精品一区二区三区在线| 国产国语露脸激情在线看| 精品一区二区三区av网在线观看 | 精品一区二区三区av网在线观看 | 亚洲成人手机| 韩国高清视频一区二区三区| 精品一品国产午夜福利视频| 大型av网站在线播放| 国产精品 欧美亚洲| 老司机靠b影院| 亚洲九九香蕉| 色视频在线一区二区三区| 少妇粗大呻吟视频| 美女高潮到喷水免费观看| 久久久久久久久久久久大奶| 亚洲成国产人片在线观看| 一本—道久久a久久精品蜜桃钙片| 我的亚洲天堂| 亚洲一区中文字幕在线| 亚洲成人免费av在线播放| 日本黄色日本黄色录像| 免费人妻精品一区二区三区视频| 国产成人啪精品午夜网站| 午夜激情av网站| 久久久久精品人妻al黑| 国产精品 欧美亚洲| 999久久久国产精品视频| 国产福利在线免费观看视频| 高潮久久久久久久久久久不卡| 丝袜喷水一区| 在线观看免费午夜福利视频| 黑人巨大精品欧美一区二区mp4| 亚洲av日韩精品久久久久久密| 大片电影免费在线观看免费| 国产精品影院久久| 黄频高清免费视频| 一级片'在线观看视频| 亚洲av成人一区二区三| 亚洲精品中文字幕在线视频| 热99久久久久精品小说推荐| 91成年电影在线观看| 亚洲欧美成人综合另类久久久| 国产日韩一区二区三区精品不卡| 亚洲精品第二区| 亚洲国产看品久久| 国产伦人伦偷精品视频| 日本av免费视频播放| 亚洲欧洲精品一区二区精品久久久| 超碰成人久久| 精品人妻一区二区三区麻豆| 亚洲九九香蕉| 精品欧美一区二区三区在线| 在线十欧美十亚洲十日本专区| 日本欧美视频一区| 国产精品av久久久久免费| 精品欧美一区二区三区在线| 国产精品免费视频内射| 国产精品香港三级国产av潘金莲| 日韩,欧美,国产一区二区三区| 波多野结衣一区麻豆| 精品第一国产精品| 国产精品一区二区精品视频观看| 亚洲国产看品久久| 久久精品国产亚洲av高清一级| 在线av久久热| 午夜福利影视在线免费观看| 97在线人人人人妻| 久久中文字幕一级| 狂野欧美激情性xxxx| 无限看片的www在线观看| 国产亚洲精品第一综合不卡| 黑丝袜美女国产一区| 免费不卡黄色视频| 99九九在线精品视频| 久久狼人影院| 女人精品久久久久毛片| 伊人久久大香线蕉亚洲五| 亚洲精品日韩在线中文字幕| 日日夜夜操网爽| 精品亚洲乱码少妇综合久久| 19禁男女啪啪无遮挡网站| 极品人妻少妇av视频| 热re99久久国产66热| 人人妻,人人澡人人爽秒播| 日本黄色日本黄色录像| 操出白浆在线播放| 中文字幕高清在线视频| 18禁观看日本| 亚洲人成77777在线视频| 老司机午夜十八禁免费视频| 丝袜美足系列| 精品人妻1区二区| 亚洲性夜色夜夜综合| 色婷婷av一区二区三区视频| 99国产精品一区二区三区| 男人添女人高潮全过程视频| 成年人黄色毛片网站| 91精品国产国语对白视频| 欧美+亚洲+日韩+国产| 亚洲国产欧美一区二区综合| 久久精品亚洲熟妇少妇任你| 久久中文字幕一级| 在线观看免费高清a一片| 宅男免费午夜| 国产片内射在线| 国产成人系列免费观看| 视频区图区小说| 久久精品亚洲熟妇少妇任你| 另类亚洲欧美激情| 午夜精品久久久久久毛片777| 国产成人精品久久二区二区免费| tube8黄色片| 久久99一区二区三区| 91精品国产国语对白视频| 精品乱码久久久久久99久播| 国产人伦9x9x在线观看| 欧美97在线视频| 日本撒尿小便嘘嘘汇集6| 丝袜在线中文字幕| 成年人黄色毛片网站| 一二三四在线观看免费中文在| 91av网站免费观看| 欧美乱码精品一区二区三区| 亚洲国产日韩一区二区| 9色porny在线观看| 免费在线观看完整版高清| 国产亚洲午夜精品一区二区久久| 自线自在国产av| 香蕉国产在线看| 国产精品免费视频内射| 久久免费观看电影| 水蜜桃什么品种好| av网站免费在线观看视频| 亚洲成人手机| 午夜福利在线免费观看网站| 美女福利国产在线| 成人亚洲精品一区在线观看| 精品高清国产在线一区| 色94色欧美一区二区| 50天的宝宝边吃奶边哭怎么回事| 国产一卡二卡三卡精品| 中国国产av一级| 国产精品香港三级国产av潘金莲| 2018国产大陆天天弄谢| 成年动漫av网址| 爱豆传媒免费全集在线观看| 欧美精品高潮呻吟av久久| 日韩一卡2卡3卡4卡2021年| 午夜视频精品福利| 99热国产这里只有精品6| 在线观看www视频免费| 一级,二级,三级黄色视频| 色婷婷久久久亚洲欧美| 大型av网站在线播放| 夜夜骑夜夜射夜夜干| 久久女婷五月综合色啪小说| 9191精品国产免费久久| 精品国产一区二区三区久久久樱花| 久久国产亚洲av麻豆专区| 老汉色av国产亚洲站长工具| 亚洲色图综合在线观看| av有码第一页| 国产成人精品久久二区二区免费| 精品久久久久久久毛片微露脸 | 80岁老熟妇乱子伦牲交| 精品一区在线观看国产| 亚洲精品一二三| 丰满人妻熟妇乱又伦精品不卡| 男女无遮挡免费网站观看| av又黄又爽大尺度在线免费看| 亚洲成人免费av在线播放| 色婷婷av一区二区三区视频| 男女午夜视频在线观看| 日韩大片免费观看网站| 天天影视国产精品| 美女扒开内裤让男人捅视频| 国产av一区二区精品久久| 美女扒开内裤让男人捅视频| 人妻 亚洲 视频| 国产亚洲午夜精品一区二区久久| 日韩欧美一区二区三区在线观看 | 最近最新免费中文字幕在线| a级毛片黄视频| 亚洲欧美一区二区三区黑人| 亚洲一区中文字幕在线| 久久免费观看电影| 亚洲欧美激情在线| 制服诱惑二区| 飞空精品影院首页| 久久精品久久久久久噜噜老黄| 欧美日韩亚洲高清精品| 一区二区av电影网| 亚洲伊人色综图| 亚洲国产av新网站| 亚洲成人免费av在线播放| 国产区一区二久久| 国产xxxxx性猛交| 欧美一级毛片孕妇| av欧美777| 亚洲欧洲日产国产| 国产91精品成人一区二区三区 | 热re99久久精品国产66热6| 桃红色精品国产亚洲av| 蜜桃国产av成人99| 18禁黄网站禁片午夜丰满| 男人舔女人的私密视频| 亚洲伊人久久精品综合| 国产成人系列免费观看| 午夜久久久在线观看| 亚洲精品久久成人aⅴ小说| 亚洲欧洲日产国产| 亚洲第一青青草原| av在线播放精品| 大香蕉久久网| 天天躁日日躁夜夜躁夜夜| 国内毛片毛片毛片毛片毛片| 不卡av一区二区三区| 亚洲国产精品一区二区三区在线| av免费在线观看网站| 亚洲精华国产精华精| 美女国产高潮福利片在线看| 午夜福利在线观看吧| 日韩一区二区三区影片| 亚洲色图 男人天堂 中文字幕| 欧美日韩黄片免| 99精品久久久久人妻精品| 天天躁夜夜躁狠狠躁躁| 成人国产av品久久久| 亚洲精品一二三| 两个人看的免费小视频| 亚洲精品粉嫩美女一区| 午夜日韩欧美国产| 狠狠婷婷综合久久久久久88av| 两性午夜刺激爽爽歪歪视频在线观看 | 久久99热这里只频精品6学生| 日本黄色日本黄色录像| 精品卡一卡二卡四卡免费| 国产av精品麻豆| 我要看黄色一级片免费的| 久久精品国产亚洲av高清一级| 老熟妇乱子伦视频在线观看 | 在线十欧美十亚洲十日本专区| 国产成人精品无人区| 亚洲精品一卡2卡三卡4卡5卡 | 国产精品久久久久久精品电影小说| 欧美精品一区二区大全| 精品少妇一区二区三区视频日本电影| 国产av又大| 亚洲精品国产av蜜桃| 一区二区av电影网| 国产日韩欧美在线精品| 亚洲精品国产色婷婷电影| 午夜福利,免费看| av国产精品久久久久影院| 成人免费观看视频高清| 无限看片的www在线观看| 纵有疾风起免费观看全集完整版| 欧美成人午夜精品| 操出白浆在线播放| 国产成人系列免费观看| 男女国产视频网站| 成年人免费黄色播放视频| 亚洲av片天天在线观看| 亚洲七黄色美女视频| av免费在线观看网站| 国产黄频视频在线观看| 91字幕亚洲| 亚洲免费av在线视频| 国产xxxxx性猛交| 丰满人妻熟妇乱又伦精品不卡| 人人妻人人爽人人添夜夜欢视频| 久久热在线av| 另类亚洲欧美激情| 亚洲综合色网址| tube8黄色片| 精品国产一区二区久久| 国产视频一区二区在线看| 丝袜美腿诱惑在线| 亚洲 欧美一区二区三区| 欧美黄色片欧美黄色片| 亚洲欧洲日产国产| av在线老鸭窝| 视频区图区小说| 窝窝影院91人妻| 欧美老熟妇乱子伦牲交| 大片电影免费在线观看免费| a级毛片在线看网站| 丁香六月欧美| 久久久久精品人妻al黑| 亚洲国产欧美在线一区| 亚洲精品久久午夜乱码| 欧美变态另类bdsm刘玥| 国产亚洲欧美精品永久| 亚洲精品国产av蜜桃| 一级片免费观看大全| 国产在视频线精品| 黄色片一级片一级黄色片| 国产精品久久久久久精品电影小说| 天天添夜夜摸| 国产片内射在线| 国产精品国产av在线观看| 高清在线国产一区| 80岁老熟妇乱子伦牲交| 精品欧美一区二区三区在线| 新久久久久国产一级毛片| 国产区一区二久久| 久久久精品国产亚洲av高清涩受| 久久久久国产精品人妻一区二区| 人成视频在线观看免费观看| 国产在视频线精品| 美女脱内裤让男人舔精品视频| 一区二区三区乱码不卡18| 丝袜美腿诱惑在线| 免费一级毛片在线播放高清视频 | 欧美日韩国产mv在线观看视频| 国产欧美亚洲国产| 精品一区二区三区av网在线观看 | 久久人人97超碰香蕉20202| 后天国语完整版免费观看| 日韩一区二区三区影片| 母亲3免费完整高清在线观看| 欧美精品啪啪一区二区三区 | www日本在线高清视频| 最新的欧美精品一区二区| 亚洲专区中文字幕在线| 人妻久久中文字幕网| 人妻一区二区av| 午夜日韩欧美国产| 亚洲精华国产精华精| 久久久久久久大尺度免费视频| av片东京热男人的天堂| 国产精品久久久人人做人人爽| 日日摸夜夜添夜夜添小说| 亚洲欧美一区二区三区黑人| 另类精品久久| 亚洲成国产人片在线观看| 18禁国产床啪视频网站| 王馨瑶露胸无遮挡在线观看| 国产精品 国内视频| 老熟妇仑乱视频hdxx| 婷婷丁香在线五月| www.999成人在线观看| 无限看片的www在线观看| 超色免费av| 亚洲少妇的诱惑av| 精品欧美一区二区三区在线| 美女午夜性视频免费| 午夜久久久在线观看| 日韩三级视频一区二区三区| 我要看黄色一级片免费的| www.av在线官网国产| 丰满人妻熟妇乱又伦精品不卡| 亚洲,欧美精品.| 精品国产乱子伦一区二区三区 | 国产激情久久老熟女| h视频一区二区三区| 熟女少妇亚洲综合色aaa.| 精品一区二区三卡| 国产男女内射视频| 午夜福利乱码中文字幕| 多毛熟女@视频| 他把我摸到了高潮在线观看 | 亚洲国产欧美网| 国产伦人伦偷精品视频| 蜜桃国产av成人99| 成人三级做爰电影| 欧美激情极品国产一区二区三区| 丝袜脚勾引网站| bbb黄色大片| 国产主播在线观看一区二区| 91精品伊人久久大香线蕉| 亚洲精华国产精华精| 黑人巨大精品欧美一区二区蜜桃| 国产精品 欧美亚洲| 午夜福利免费观看在线| 亚洲精品成人av观看孕妇| 日本撒尿小便嘘嘘汇集6| 18禁国产床啪视频网站| 亚洲专区字幕在线| 男人操女人黄网站| 青春草视频在线免费观看| 啦啦啦在线免费观看视频4| 国产精品久久久久久人妻精品电影 | 久久人人97超碰香蕉20202| 多毛熟女@视频| 国产成人精品在线电影| 日韩一区二区三区影片| 一本色道久久久久久精品综合| 亚洲av美国av| 在线十欧美十亚洲十日本专区| 久久香蕉激情| 在线观看免费视频网站a站| 男男h啪啪无遮挡| 亚洲国产欧美一区二区综合| 人人妻,人人澡人人爽秒播| 搡老乐熟女国产| 精品国产乱码久久久久久男人| 妹子高潮喷水视频| 久久久国产一区二区| 久久久国产精品麻豆| 欧美成人午夜精品| 狂野欧美激情性xxxx| 亚洲精品美女久久av网站| 精品福利观看| 色婷婷av一区二区三区视频| 深夜精品福利| av不卡在线播放| 欧美日韩福利视频一区二区| av视频免费观看在线观看| 91九色精品人成在线观看| 久久性视频一级片| 日本欧美视频一区| 在线观看免费高清a一片| 丝袜人妻中文字幕| 国产成人系列免费观看| 国产成人免费无遮挡视频| 亚洲av国产av综合av卡| 欧美av亚洲av综合av国产av| 日日爽夜夜爽网站| 久久精品成人免费网站| 一个人免费看片子| 中文字幕av电影在线播放| 日韩人妻精品一区2区三区| 精品人妻一区二区三区麻豆| 午夜免费鲁丝| 天天操日日干夜夜撸| 日本五十路高清| 午夜免费鲁丝| 国产精品 国内视频| 国产亚洲av片在线观看秒播厂| 看免费av毛片| 免费看十八禁软件| 一个人免费看片子| 久久国产亚洲av麻豆专区| 亚洲精品久久久久久婷婷小说| 午夜影院在线不卡| 男男h啪啪无遮挡| 久久性视频一级片| 精品一品国产午夜福利视频| 欧美乱码精品一区二区三区| 国产熟女午夜一区二区三区| 在线永久观看黄色视频| 99国产精品一区二区三区| 国产成人一区二区三区免费视频网站| 人妻 亚洲 视频| 欧美人与性动交α欧美软件| 黄色片一级片一级黄色片| 人妻一区二区av|