• <samp id="u8mge"></samp>
  • <samp id="u8mge"></samp>
  • <samp id="u8mge"><s id="u8mge"></s></samp>
    論文網首頁|會計論文|管理論文|計算機論文|醫藥學|經濟學論文|法學論文|社會學論文|文學論文|教育論文|理學論文|工學論文|藝術論文|哲學論文|文化論文|外語論文|論文格式
    中國論文網

    用戶注冊

    設為首頁

    您現在的位置: 中國論文網 >> 計算機論文 >> 計算機理論論文 >> 正文 會員中心
     計算機應用論文   計算機理論論文   計算機網絡論文   電子商務論文   軟件工程論文   操作系統論文   通信技術論文
    球類旋轉對球軌跡的影響
    【摘 要】 為了研究旋轉的球產生馬格努斯效應的氣動機理,本文以棒球為例,以伯努利方程為基礎,對棒球在旋轉狀態下的流場進行分析,給出magnus效應的數學表達式。因為棒球體在空氣中運動時, 受到的阻力不僅與其速度有關而且和表面的光滑程度有關,由此分析反magnus效應下棒球的s形球。結果表明,當球速足夠快、轉速足夠大、球更光滑時,會產生與馬格努斯力方向相反的力。最后,嘗試運用流體力學解釋蝴蝶球左右晃動的原因。
      【關鍵詞】 流體力學 棒球 magnus力 阻力 運動軌跡
      如今各種球類運比賽已經成為世界中的焦點,能夠打出一個漂亮的技術球對比賽結果的取勝起到了重要作用。各種技術球中,基于馬格努斯效應的曲線球為主。馬格努斯效應,是指一個沿著對稱軸旋轉的圓柱體在垂直對稱軸的來流中會受到一個側向力的作用,是以第一個正確解釋該現象的德國物理學家馬格努斯的名字來命名的。由于棒球由一塊塊的皮革縫合而成,既不能看成是理想的光滑球體,也不能作為氣短粗糙的球體來對待,這就使得分析棒球的受力及運動過程較為復雜。因此,分析馬格努斯效應及其在棒球運動項目中的應用研究,對于進一步理解馬格努斯效應以及在棒球運動的訓練有著重要的指導意義和實踐意義。
      1 理論背景簡介
      邊界層與阻力系數,球體運動通過邊界層和外界發生了密切關系。因為邊界層內的空氣自球面向外轉速越來越小,每層之間就會發生相對運動和相對摩擦。這些摩擦將會把球體的能量消耗掉,從而減慢了球體的運動。這就是流體中摩擦阻力的由來。在高速流動中,球體外的空氣會不斷地分離(邊界層分離,boundary layer separation)。www.zhidachem.com邊界層的分離通常發生在在球體后方,從而形成一個低速區。在低速區中,空氣流動紊亂,壓力相對較低。因此球體前方的空氣就對球體后方的空氣產生了一個向后的力,我們把它稱為 “形狀阻力”。摩擦阻力和形狀阻力共同作用共同構成了球體在流體中運動過程中受到的阻力。為了讓具體的實驗結果具有普適性,科學家們用一個阻力系數來表示阻力的大小。對于同一個物體同樣的迎風飛行的速度和方向而言,阻力系數越大就意味著阻力越大。
      2 棒球三種飛行軌跡成因分析
      考慮在上面簡單邊界層和阻力系數理論基礎上,分析magnus效應、反magnus效應和蝴蝶球的具體成因。
      2.1 曲線球中的magnus效應
      棒球在空中運動時,一邊向前飛行,一邊繞對稱軸旋轉,則由于棒球的旋轉和空氣粘性的共同作用,在棒球周圍的附面內產生環流,前方來流和環流共同作用的結果,在來流和環流同方向的一側(圖1中b側),流速加快。在反方向的另一側(圖1中a側),流速減慢, 根據伯努利原理,流速加快的一側壓力下降,流速減慢的一側壓力升高, 二側的壓力差對棒球產生側向作用力稱為馬格努斯力,方向與棒球的瞬時轉軸垂直,且與棒球的運動方向垂直。
      馬格努斯效應也可被歸結為邊界層的不對稱分離。在旋轉的球體中a側,邊界層里的空氣順著球體表面向后運動時,由于速度較小,則邊界層分離較早。b側相反,邊界層分離較晚。結果,a側更接近真空,b側被空氣包裹的更嚴。這樣,更加接近真空的a側就有了一個更大的低速區,從而產生了更大的壓強,使球向b側運動,就產生了曲線球。而且隨著轉速增加,這種趨勢更加強烈。
      2.2 反magnus效應
      如果投球手投出的是一個更快、轉速更大、更加光滑的球,就會產生一種飄忽不定的s形球,而反magnus效應就解釋了這種s形球。阻力曲線圖上,隨著速度(橫坐標的雷諾數)增加,我們發現阻力系數(縱坐標)有個突降。這個并不是實驗不準確造成的,而是湍流產生的作用。發生阻力系數突降的雷諾數被稱作臨界雷諾數。如果一個不旋轉的球體,速度達到一定程度,球體雷諾數會超過臨界雷諾數(大概~)。邊界層里的空氣將會突然變成湍流,邊界層轉化為湍流邊界層。
      湍流邊界層擁有更大的能量,可以在球壁上附著很遠。球體如果旋轉起來的話,a側的轉速足夠大,由于湍流a側球壁上會附著比另一側更多的空氣,從而減弱了真空部分對應的低速區,從而產生了與magnus力方向相反的力(反magnus效應)。隨著速度下降,球體運動的雷諾數又低于了臨界雷諾數,湍流就會消失。根據前文的推斷,球體又瞬間轉向了b側。轉彎的瞬間,轉速相對增加,湍流可能再一次出現。因此雷諾數有可能在臨

    界值附近反復往返變化,而阻力系數就會來回的突變,所以球體運動方向飄忽不定,因此出現了詭異的s形球。
      2.3 完全不旋轉的球——蝴蝶球(butterfly or knuckleball)
      在棒球比賽中會出現一種令打者完全追不上的球。這種變線球會在球的運動過程中,球的軌跡會向不明方向發生偏離。蝴蝶球在在直線飛行的過程中,球體不產生旋轉。
      考慮到棒球的球面表皮與表皮之間的粘合部存在著接縫,這就使得球體表面的不完全平滑。而球體表面的不規則致使球體在運行過程中,其四周產生不對稱的氣流,致使球體向氣壓小的方向上偏離,從而令打者產生像蝴蝶一樣四處亂晃的感覺。
      3 結論與應用
      本文分析時力學模型的建立與真實球體運動狀態有一定的差距,但據此進行的受力分析以及定量計算能夠在一定程度上反映真實流體場特點。
      在棒球教學訓練和實際應用中,曲線球技術的應用非常普遍,是重點也是難點,所以它對球員的技術水平要求比較高。在擊球的過程中,當擊球的力正好通過球心時,球不旋轉,此時可能產生蝴蝶球。如果擊球的力不通過球心,則在馬格努斯效應或反馬格努斯效應下可能會產生其他曲線球。
      總之, 像其他大多數體育運動一樣,棒球運動有其自身的復雜性,要作精確計算幾乎是不可能的。對各類特技球產生原因和在球類運動中的應用進行研究,不僅有助于我們更深一步理解流體力學中的一些經典理論,對球類運動的教學水平、訓練效果和競賽成績也有著重要的指導意義和實踐意義。
  • 上一個計算機論文:
  • 下一個計算機論文:
  •  更新時間:2014-08-31 10:49:38  作者:佚名 [標簽: 旋轉 軌跡 影響 ]
    姓 名: *
    E-mail:
    評 分: 1分 2分 3分 4分 5分
    評論內容:
    發表評論請遵守中國各項有關法律法規,評論內容只代表網友個人觀點,與本網站立場無關。
    旋轉整流器故障在線診斷模塊設計
    | 設為首頁 | 加入收藏 | 聯系我們 | 網站地圖 | 手機版 | 論文發表

    Copyright 2006-2013 © 畢業論文網 All rights reserved 

     [中國免費論文網]  版權所有

    澳客彩票平台澳客彩票主页澳客彩票网站澳客彩票官网澳客彩票娱乐 2595b.com | www.66376k.com | ylzz.com | www.kxjfg.com | www.643477.com | 58-mm.com | www.46630.org | 118cp4008123.com | www.yh7088.com | www.6364e.com | 3416c.com | www.5049x.com | www.88325n.com | 5856dd.com | www.hg97hg97.com | www.qmkl3.com | 554fq1.com | www.7920s.com | www.3691m.com | www.122888a.com | www.77114w.com | www.81233w.com | xg9111.com | www.202901.com | www.drf0432.com | x4255.com | www.00840c.com | www.21365oo.com | 518cp.com | www.44118j.com | fll8.com | www.320493.com | www.055838.com | hgw168w.com | www.7036e.com | f35151.com | www.097318.com | www.xpj16682.com | jlshckj.com | www.34788u.com | www.9737hh.com | pjjiangsu.com | www.357411.com | www.cp0018.com | 80892vv.com | www.524880.com | www.4963uu.com | k45638.com | www.183699.com | www.969709.com | 2381002.com | ii4675.com | www.5719b.com | www.3371777.com | 4048eee.com | www.zpw100.com | www.8494l.com | 908080x.com | xldwh.com | www.317990.com | www.4212m.com | 2jsttt.com | www.022197.com | www.469704.com | 226688.net | 33111199.com | www.52303b.com | 9339999n.com | www.202437.com | www.d12189.com | 73567tg12.com | 90307l.com | www.90920.com | www.55155z.com | ry7722.com | www.712250.com | www.4972g.com | 1665p.com | 1434a.com | www.9928f.com | www.088878.com | df6529.com | 500000796.com | www.hg118444.com | www.4788msc.com | 4488m.com | www.50054e.com | www.290227.com | www.358012.com | 0332h.com | www.931669.com | www.55060a.com | www.blr0088.com | 33382w.com | www.810872.com | www.673888c.com | www.033033g.com | 5144.com | www.637477.com | www.12136m.com | www.ra1116.com | y088.cc | www.178389.com | www.2228229.com | www.3642.com | 3049b.com | w7454.com | www.655802.com | www.106846.com | www.cs55222.com | jbb71.cc | 6095app.com | www.770981.com | www.hbet96.com | www.238288.com | 131aa.net | 074f7.com | www.966019.com | www.9978bb.com | www.am4088.com | JS1388o.com | 883399z.com | www.599843.com | www.1764q.com | www.3195555.com | ks2227.com | 5906mm.com | 0986.com | www.ch8123.com | www.52062b.com | www.134222.com | 55984u.com | 7003n.com | 67888s.cc | www.764499.com | www.4809h.com | www.597567f.com | www.88hggj.com | nn500f.com | 36502w.com | www.562500.com | www.3978h.com | www.6776cc.com | www.sbet567.net | d5429.com | 13222x.com | 6261hh.com | www.cp0123.cc | www.hb598.cc | www.80188t.com | www.xh4499.com | www.xpj9999.cc | 2jslll.com | pj88ll.com | yth12.net | www.859509.com | www.bet353655.com | www.59199.com | www.585234.com | www.js80288.com | 35cc.vip | 3405uu.com | 07074688.com | 69234.cc | www.53900i.com | www.ck9292.com | www.4323m.com | www.140086.com | www.rgcp444.com | www.hg5100.com | www.143800.com | 32250.com | 29533.com | 6878.am | 3089.com | www.099210.com | www.755864.com | www.9928j.com | www.h6610.com | www.6hg6668.com | www.566846.com | www.16297777.com | www.8882558.com | www.vns20033.com | 66458q.com | 00bb8331.com | 7788332.com | 222.am | 13222r.com | yy909.com | 0600y.cc | ybc17.com | www.51515v.com | www.609713.com | www.ck9292.com | www.12455p.com | www.rfdc02.com | www.048.com | www.742022.com | www.bet91483.com | www.682260.com | www.sportsinfo8.net | www.hg6688.com | www.0904xpj.com | www.js.tt | www.44xpjdc.com | www.4123k.app | www.5665699.com | 97297d.com | 7935y.com | 28484000.com | feicai0393.com | hg3006.tw | bet577v.com | 56988bb.com | 0747gg.com | quyoudaren.com | bet667766.com | 5478d.com | dadidaohang.com | 11163322.com | 22299uu.com | 2257013.com | nn500n.com | 22207c.com | 9971009.com | bwin8u.com | 9339999.com | 3405c.com | 3405dd.com | 8159r.cc | 5478444.com | 80892mm.com | 2677kkk.com | feicai0311.com | 9479c3.com | 5906vv.com | hggjtg18.com | jsc19.com | 9007004.com | 61652z.com | 3844yy.com | 3559666.cc | 077688.cn | 61322222.com | 50099x.com | 0600p.cc | www.206181.com | www.pj7058.com | www.hg8447.com | www.4965b.com | www.799666j.com | www.3116s.com | www.960620.com | www.1500777.com | www.06387711.com | www.c63568.com | www.mgm777c.com | www.51331c.com | www.979505.com | www.202337.com | wfcp333222.com | 118888s.com | m0007.com | 8036aa.com | www.xw111111.com | www.3189001.com | www.r4042.com | www.73990e.com | www.1466q.com | www.9818n.cc | www.480840.com | 4270ss.com | 9994cc7.com | 3568j.com | 016458.com | www.vns9983.com | www.xpj237.com | www.377838.com | www.hr1855.com | www.3478p.cc | xpj66888.com | 2636.cc | wfcp444333.com | www.hg9945.com | www.amyh9888.com | www.1108617.com | www.3116j.com | www.033654.com | www.qilc3.com | rgcp.com | a44.com | ylzz4444.com | www.bmw9968.com | www.865336.com | www.50024d.com | www.551727.com | 7742xx.com | hbs480.com | 5130.cc | www.2221188.com | www.601710.com | www.26299p.com | www.195090.com | 2757v.com | 9303066.com | www.76543z.com | www.hr888vip.com | www.89777w.com | www.808791.com | tz1555.com | 272y.net | www.l22365.com | www.377838.com | www.07088.com | www.234892.com | hgw168p.com | 7088000.com | www.k4625.com | www.588860.com | www.rrle3.com | hgyz88.com | 4165.com | www.msc99.la | www.535083.com | www.805733.com | 2019a.cc | 44112229.com | www.168005.com | www.345311.com | www.216750.com | 5099bb.com | www.8806js.com | www.tyc328.com | www.84499p.com | www.35155i.com | 566777h.com | www.695395.com | www.4996sc.com | www.tcsj.com | yh77.com | lts2883.com | www.9149.com | www.1035p.com | 666vn77.com | 3651266.com | www.584222.com | www.fg9908.com | www.36788e.com | 36403311.com | www.888zr61.com | www.7240m.com | www.81678u.com | lc99j.com | www.yh48826.com | www.126a56.com | www.126019.com | 3435.com | www.64821122.com | www.81608g.com | www.404499.com | 8344111.com | www.2846r.com | www.7886268.com | 6hcc99.com | tt00558.com | www.773456.com | www.83993z.com | 5443o.com | 20775588.com | www.704903.com | www.506972.com | 4465p.com | www.239988.com | www.18690a.com | 01234iii.com | www.xj6666.com | www.js6969.com | www.79520a.com | 22993882.com | www.jz95588.com | www.679957.com | 9068c.com | www.688222.com | www.36788h.com | 55009193.com | www.4853c.com | www.3333bj.com | 1408.am | www.m1.10500ww.org | www.7036bb.com | 1775hh.com | 66876h.com | www.2737012.com | www.160326.com | 4131.com | www.7225v.com | www.66621o.com | 6261ss.com | www.hg98vip8.com | www.196039.com | 88807g.com | www.673888k.com | www.71233i.com | 3178v.com | www.4546500.com | 2698n.com | hgw168x.com | www.159957.com | vns365c.com | www.3337hg.com | www.3978b.com | 5350j.com | www.e2229e.com | www.3478k.cc | 3957m.com | www.3g88.com | www.66653i.com | 2546x.com | www.0072721.com | 11422x.com | www.0860i.com | www.6364i.com | 4255jjj.com | www.163a5.com | www.156050.com | 4052c.com | www.222999qipai.com | 3678iii.com | www.133414.com | www.sjgc9.com | 9158bo.com | www.00778a.com | 022573.com | www.8814e5.com | www.885pz.com | vns80579.com | www.l3410.com | xinli18sport.com | www.831813.com | www.954321b.com | pj88jj.com | www.k444.net | www.451770.com | 5003tt.com | www.3978m.com | f14666.com | www.u69096.com | 89892vv.com | www.071094.com | www.565753.com | 3822o.com | www.77802t.com | 4022jj.com | www.91779u.com | 3m412.com | www.ke00852.com | www.137105.com | www.1019990.com | www.3126aa.com | zz00558.com | www.pj888l.com | 1294c.cc | www.559990.com | 2229tz.com | www.hf9011.com | 3089u.com | www.amdc0005.com | www.77803u.com | www.4938c.com | www.701547.com | www.6033g.com | www.2109t.com | 921290.com | www.2118037.com | 4289k.com | www.zzyl62.com | ts698.com | www.369407.com | boyingyule.com | www.06617b.com | ag80.vip | www.55070b.com | 82365k.com | www.7415pp.com | cp088s.com | www.8313p.com | 1389ff.com | www.5099vv.com | 97886699.com | www.53096666.com | o77304.com | www.xpj2050.com | 610260.com | www.5049l.com | 7935v.com | www.js12258.com | www.33112i.com | www.777444d.com | www.c6823.com | 66775002.com | www.cbw222.com | 5010.com | www.c6823.com | www.yl12007.com | www.cb0999.com | www.yh8003.com | www.890702.com | www.yddc666.com | www.652631.com | www.bet3651014.com | www.672366.com | www.55225454.com | www.290038.com | www.777789pj.com | 444000j.com | www.569393a.com | 73055i.com | www.4727188.com | 9694o.com | www.00878.com | 9659t.com | www.707wb.com | 59889t.com | www.hx6695.com | www.32126w.net | www.290165.com | www.hg3326.com | xh6.org | www.28000b.com | www.606643.com | www.2626sun.com | 4195y.com | www.beb100.com | js001295.com | www.33678xx.com | 4289k.com | www.33112t.com | www.long260.com | www.296233.com | www.xg189.com | 33432o.com | www.07679l.com | ys2222.com | www.axc2.com | www.336suncity.com | 9694i.com | www.3396877.com | vvv67890.com | www.50024r.com | www.pj9086.com | q77304.com | www.27363p.com | 0245i.com | www.29277hh.com | 73567tg17.com | www.178281.com | www.3846z.com | 3066rrr.com | www.77802l.com | www.682844.com | 48455.com | www.7788msc.com | 316t.cc | www.66qxc.com | www.8679822.com | 8030s.com | www.52062f.com | 3178z.com | www.244949.com | www.138cpp.com | 915901596.com | www.9155g.com | www.29886t.com | 3132121.com | www.1764u.com | 7334z.com | www.180121.com | www.gt111666.com | yhliaoning.vip | www.803733.com | www.980999.com | 06385959.com | www.15855.cc | www.1213699.com | pj968810.com | www.50788j.com | 0033j.cc | 8957.com | www.835991.com | 22555004.com | JS1388k.com | www.40288h.com | 3016.com | 0289p.com | www.86730.com | 5030.com | 500000512.com | www.200068.com | 1064.com | zhcpll.com | www.4833044.com | www.yh8211.com | 5651j.com | www.0270s.com | www.2061270.com | 4186.com | www.3416e.com | www.5860x.com | 78808t.com | www.668566.com | www.4694u.com | 2247x.com | z444000.com | www.1434l.com | www.76543b.com | bet99979.com | www.33997z.com | www.hg8915.com | 3640x.com | www.382780.com | www.38138t.com | gd0621.com | 4066r.com | www.08588j.com | www.980999.com | 52599s.com | www.101363.com | www.78680j.com | www.sjcp111.com | 44p88.cc | www.809216.com | www.829797a.com | www.pu5555.net | 1591ppp.com | www.371e.cc | www.03.bet | 0747mm.com | 6hao999.vip | www.71233x.com | www.ok633.com | 00jj8331.com | 1977xpj.com | www.33598x.com | www.114654.com | 163105.com | 1590.com | www.1035r.com | www.644886.com | 500000598.com | 11422.cc | www.807860.com | www.k1432.com | www.7620679.com | 776072.com | www.8039r.com | www.752568.com | 33567m.com | 7196z.com | www.2875q.com | www.9b002.com | www.dhy0707.com | hjdc678.com | www.629293.com | www.3421d.com | www.45hg.com | 8901w.com | 15856r.com | www.055.la | www.cn365i.com | www.4938p.com | 70118q.com | 5856rrr.com | www.44fzc.com | www.cn365a.com | www.9996hh.com | 63389.com | jixiang10.com | www.754918.com | www.241099.com | www.z6777.com | 2934x.com | 1036.com | 32424b.com | www.35918r.com | www.4694n.com | www.777444c.com | 68228y.com | 22556e.com | www.314213.com | www.340095.com | www.56766.com | www.ag6.com | 8742u.com | 3379xx.com | www.560231.com | www.222067a.com? | www.l5504.com | www.87680t.com | 00vv8331.com | 30019rr.com | hj5068.com:8888 | www.076wy.com | www.2997773.com | www.blm139.com | www.pjshandong.com | 11cc8332.com | q3410.com | 09t55.com | www.cf9903.com | www.i98478.com | www.4agcpw.com | www.333133y.com | 4997u.com | 11749.com | 1288cc.com | www.196303.com | www.890c.com | www.rrqp222.com | www.cp0014.com | www.98am444.com | 40033yy.com | jidu9.com | 91590.com | www.854242.com | www.904027.com | www.06820k.com | www.114654.com | www.22753.com | 50020099.com | 20055533.com | 0860dh.com | 73055i.com | 32126q.net | www.896950.com | www.85858hh.com | www.l32031.com | www.qj2.co | www.095985.com | www.kf5656.com | 168cp-o.com | 655ib.com | xpjggzz.com | sqrc8.com | 17715.com | www.506433.com | www.055gw.cc | www.81678w.com | www.785409.com | www.80188d.com | www.dfh271.com | www.066983.com | www.t8003.com | www.7435g.com | 1077aaa.com | m3405.com | 8988ee.com | 66458h.com | 5589v.com | l8159.cc | dahongying.com | www.097067.com | www.550419.com | www.914979.com | www.cbw222.com | www.50051g.com | www.3066.com | www.97828q.vip | www.91779f.com | www.4963z.com | www.938s.cc | www.cqbdgg.com | www.hg00868.com | www.5590777.com | www.www6161msc.com | www.3569f.com | www.70088hg.com | www.033033j.com | 9964g.com | jjjj008.com | 3156qqq.com | 7141bb.com | 477105.net | 54240033.com | 111wns88.org | 9355ema.com | 092120.com | 44222007.com | hhvip666.com | x3405.com | 3890a.com | 63965555.com | 878365nn.com | 33kk8331.com | 00048s.com | 985599.com | gg2205.com | 888p1.cc | 496677.com | www.sjg500.com | www.xpj0880.com | www.28758z.com | www.9444hg.com | www.76543u.com | www.xpj88004.com | www.hg8855.com | www.551324.com | www.44799.com | www.hj358.com | www.t948t.com | www.4212t.com | www.9737yy.me | www.2021e.com | www.4546700.com | www.55676y.com | www.5958127.com | www.991qp.com | www.50051y.com | www.yi816.com | www.914983.com | www.473552.com | www.178125.com | 7YL7999.com | feicai0451.com | 111122vv.com | hh03.com | r01234.com | 17798888.com | 1624gg.com | www.7720p.com | www.b922.com | www.49200a.com | www.948.com | www.mgm868008.com | www.8905g.com | www.6628229.com | www.87467.com | www.ct8822.com | www.330715.com | 2075.com | 1294j.com | 0208ll.com | 33xx8331.com | 111122cc.com | www.0679555.com | www.hg7803.com | www.163a44.com | www.0622.com | www.50051hh.com | www.cb5388.com | www.210793.com | judingbo0.com | 33335309.com | yhguizhou.vip | 2618zz.com | www.25288j.com | www.327365.com | www.06820w.com | www.85330.com | www.axc4.com | www.86267v.com | 01885z.com | 7681003.com | 2455u.com | www.621155c.com | www.09766.com | www.55545l.com | www.v774477.com | www.2632n.com | www.153918.com | sqrc8.com | 5003hh.com | www.68666c.com | www.amjs799.com | www.00773b.com | www.531089.com | www.811597.com | bb888811.com | jidu22.com | 500000431.com | www.pj6545.com | www.3306488.com | www.3797733.com | www.809296.com | 50024466.com | 67890uu.com | 5855qq.com | www.2233ok.com | www.60886i.com | www.8999ka.com | 4975.am | 3330168.com | jinguan2255.com | www.84859.com | www.7893.cc | www.33112m.com | www.188393.com | k4255.com | 2381yy.com | www.071097.com | www.4521j.com | www.070.la | 099568.com | pp01234.com | www.vnsr500.com | www.3846s.com | www.js1045.com | www.363067.com | 30688c.com | 123456bb.cc | www.js00369.com | www.44118w.com | www.hm6622.com | 7945gg.com | 38850077.com | www.007733.com | www.2544g7.com | www.hx3355.com | 8030h.com | drcp666.com | www.44889u.com | www.c3410.com | www.820737.com | 78808l.com | 6641818.com | www.s33558.com | www.68365b.com | www.655061.com | 2846t.com | 5002ttt.com | www.ag6215.com | www.36166hh.com | zz180.com | c15666.com | www.88807b.com | www.00778f.com | www.900122.com | 7068.com | kk4675.com | www.98698r.com | www.2500o.com | 3616f.com | 2479.com | www.138cpr.com | www.51515r.com | 656pj.com | pj31.com | www.6787749.com | www.15355h.com | 88021.com | 2381ggg.com | www.9788t.com | www.22603.cc | x7666.com | 500000378.com | www.518737.com | www.15355k.com | 28824y.com | zhcp40.com | www.mm55826.com | www.950665.com | 7196ll.com | www.vns998.com | www.792073.com | www.398118.com | 7726hd.com | www.hg5728.com | www.550021j.com | 2355b.com | 5589a.com | www.6661ylg.com | www.908673.com | 495a.cc | www.7545q.com | www.985479.com | 3018cc.com | 7779m.cc | www.80188r.com | www.483864.com | r14666.com | www.www-85594.com | www.22505.cc | 1483b.com | www.3643u.com | www.pj99n.com | 7003pp.com | 1665p.com | www.79095l.com | www.81678e.com | fc9818.com | www.534359.com | www.606930.com | 3467z.am | www.msc855.com | www.czg7.com | pj677.me | www.698774.com | www.2408e.cc | 5309h.com | www.hd2894.com | www.40484.com | yhsichun.vip | www.06797x.com | www.33598y.com | 70118u.com | 2618zz.com | www.4102k.com | sbd023.net | www.hg6364.com | www.3775p.com | 3435t.com | www.9996kk.com | www.83033r.com | 76543d.com | www.pj903.com | www.11csj.com | 3405mmm.com | www.v4042.com | www.641277.com | hd7720.com | www.am00000.com | 91019.net | www.55123.com | www.ejylc13.com | n08199.com | www.vns6036.com | www.3416l.com | 3957t.com | www.938u.cc | www.346377.com | 009900t.com | www.70669b.com | 1234vn.cc | www.40033.1540033.com | www.7782h.com | 93922z.com | www.4212t.com | www.91233o.com | www.1869d.com | www.8d818.com | 422yh.com | www.460707.com | www.550134.com | ddd2267.com | www.3775e.com | 58802o.com | www.609494.com | www.607316.com | 83377s.com | www.297555.com | 6556e.com | www.3122vv.com | www.369053.com | 5369s.com | www.bet73e.com | 88ee940.com | www.88166r.com | 66876f.com | www.58777f.com | www.905844.com | 996622vv.com | www.48330g.com | 0524.com | www.360cp.com | 0208vv.com | www.16639.com | www.849129.com | 6245q.com | www.hg6767.com | 8344aa.com | www.xpj556677.com | bet36500220.com | www.ms488.com | www.504377.com | www.bh33345.com | www.90767.com | 76886p.com | www.l98478.com | 30178899.com | www.huangma28.com |