• <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 ?

    小型掠入射式近邊X射線吸收譜儀的設(shè)計

    2018-04-19 10:48:58陳晨曦陽金春水
    中國光學(xué) 2018年2期
    關(guān)鍵詞:譜儀入射角譜線

    陳晨曦陽,金春水,王 君,謝 耀

    (1.中國科學(xué)院 長春光學(xué)精密機械與物理研究所 應(yīng)用光學(xué)國家重點實驗室,吉林 長春 130033;2.中國科學(xué)院大學(xué), 北京 100049)

    1 引 言

    Introduction

    近邊X射線吸收精細結(jié)構(gòu)(Near Edge X-ray Absorption Fine Structure,NEXAFS)光譜是由吸收原子的內(nèi)層電子吸收光子躍遷到外層的空軌道產(chǎn)生的[1],反映了吸收原子與周圍原子間的相互作用,因此通過分析近邊結(jié)構(gòu)可以獲得吸收原子的電子結(jié)構(gòu)和近鄰幾何結(jié)構(gòu)信息。與電子能量損失譜(EELS)和X射線拉曼散射(XRS)等方法相比[2],NEXAFS技術(shù)不易造成輻射損傷,對樣品的物理狀態(tài)沒有要求,適用范圍廣泛。起初,這項技術(shù)僅僅用于研究小分子,隨著理論和實驗技術(shù)的發(fā)展,如今,它已經(jīng)廣泛應(yīng)用于各種復(fù)雜大分子的研究,例如有機高分子材料[3-4],土壤、大氣中的天然有機物[5-6],甚至是水環(huán)境中的生物分子[7]。

    Near Edge X-ray Absorption Fine Structure(NEXAFS) spectrum is produced due to transition of the inner electrons of absorbing atoms to the outer unoccupied molecular orbital by absorbing photons[1]and reflects the interaction of absorbing atoms with ambient atoms, so the information on the electron structure and adjacent geometric structure of absorbing atoms can be obtained through analyzing the near edge structure. In comparison with the methods such as electron energy loss spectroscopy(EELS), X-ray Raman Scattering(XRS),etc.[2], the NEXAFS technology doesn′t result in radiation damage easily and has no requirements for the physical state of samples, so it has a wide range of application. At first, this technology was only used to study small molecules. With the development of theories and experimental technologies, it has now been extensively applied in the study of various complex macromolecules,e.g. organic polymer materials[3-4], natural organic substances in soils and atmosphere[5-6], and even biomolecules in water environment[7].

    目前,國內(nèi)外大多數(shù)NEXAFS實驗都是在同步輻射線上進行的,然而同步輻射裝置機時非常有限,且建造運營成本極高,短期內(nèi)難以滿足大量NEXAFS科研需求。因此,研究基于小型X射線源的實驗裝置具有重要研究意義和實用價值。近年來,國內(nèi)外的研究人員已經(jīng)基于激光等離子體光源開展了許多相關(guān)工作。Osamu Yoda等人[8]利用超環(huán)面鏡收集X射線、平場光柵和彎晶分別對低能和高能光子分光,微通道檢波器二極管陣列系統(tǒng)作為探測器,設(shè)計了一套工作在100~3 000 eV的吸收譜儀;Hidetoshi Nakano等人[9]使用了兩個凹面鏡將X射線聚焦到樣品上,用平場光柵分光,再由微通道檢波器和CCD接收,在12 nm處分辨率(λ/Δλ)250;U Vogt等人[10]利用透射光柵和CCD搭建了一臺用于水窗波段的實驗裝置,成功獲得了β胡蘿卜素的近邊吸收譜,但是這套裝置在4.4 nm處的分辨率只有300,不足以區(qū)分有機物吸收譜的所有典型峰,后來他們用離軸反射波帶片取代了透射光柵[11],分辨率提高了一倍,獲得的聚酰亞胺和PET(poly ethylene terephthalate)薄膜的近邊吸收譜均與同步輻射上的實驗結(jié)果相當(dāng);Christian Peth等人[12]研制的吸收譜儀以消像差的平場光柵作為分光器,背照射式CCD作為探測器,在2.87 nm處分辨率200,他們使用這套設(shè)備研究了高分子材料、生物樣品以及土壤提取物的NEXAFS譜[12,7,13]。

    At present, most domestic and foreign NEXAFS experiments are conducted on synchrotron radiation lines, but the machine-hour of synchrotron radiation facilities is very limited. Their construction and operation cost is extremely high, and they are difficult to meet the needs of plentiful NEXAFS scientific studies in short term. Hence, the research on the experimental equipment based small X-ray sources has vital research significance and practical value. In recent years, domestic and foreign researchers have carried out a lot of relevant work based on a laser plasma source. Osamu Yodaetal.[8]designed a set of absorption spectroscopy apparatus working at 100-3 000 eV using toroidal mirrors to collect X-rays, using flat-field gratings and bent crystals to carry out light splitting of low energy and high energy photons respectively and using a micro-channel detector diode array system as a detector. Hidetoshi Nakanoetal.[9]used two concave mirrors to focus X-rays onto samples, flat-field gratings to carry out light splitting, and used micro-channel detectors and CCD to receive information, with the resolution at 12 nm being(λ/Δλ)250. U Vogtetal.[10]erected a set of experimental equipment in the water window using transmission gratings and CCD; with the equipment, they successfully obtained the near edge absorption spectrum of β carotene, but the resolution of the equipment was only 300 at 4.4 nm and it was not enough to differentiate all typical peaks of the absorption spectrum of organic substances. Afterwards, they replaced transmission gratings with off-axis reflection zone plates[11], the resolution of the equipment was increased by 100%, and the obtained near edge absorption spectrum of both polyimide and poly ethylene terephthalate(PET) film was equivalent with the experimental result from synchrotron radiation. Christian Pethetal.[12]developed an absorption spectrometer using an aberration-reduced flat-field grating as the light splitter and back-illuminated CCD as the detector. The resolution of the spectrometer is 200 at 2.87 nm; they studied the NEXAFS spectrum[12,7,13]of high polymer materials, biological samples and soil extracts using the spectrometer.

    現(xiàn)有的小型NEXAFS光譜儀的研究主要采用透射式光路,這種結(jié)構(gòu)只能得到體相信息,為了獲得高信噪比的譜線,被測樣品一般為無支撐的薄膜結(jié)構(gòu),且厚度需嚴格控制,通常為100~200 nm,制備困難。而另一種掠入射式光路則對樣品厚度沒有要求,因為只有表面很薄的分子層產(chǎn)生吸收,反射光較強,信噪比高,能適應(yīng)較弱光源;同時還具有很強的表面敏感性,可以用于表面分子變化的研究。近年來,具有特殊光電性質(zhì)的有機材料[14-16]的研究越來越多,本文基于掠入射光路,利用小型的氣體激光等離子體X射線光源,設(shè)計了一臺用于研究有機材料碳1s NEXAFS譜的近邊X射線吸收譜儀,并對譜儀的分辨率等指標(biāo)以及元件的裝配公差進行了分析。

    A transmissive light path is mainly used in the study of the existing compact NEXAFS spectrometers, but with this structure, only bulk phase information can be obtained. In order to obtain high SNR spectral lines, the tested sample is generally an unsupported membrane structure, and its thickness needs to be strictly controlled and tends to be 100-200 nm, so its preparation is difficult. Another grazing incidence light path has no requirement for sample thickness. This is because only the very thin surface molecular layer has an absorption. The reflected lights is strong with high SNR, and the grazing incidence light path is suitable for weak light sources. In addition, it also has a very strong surface sensitivity and can be used in the study of surface molecule variation. In recent years, there are more and more studies of organic materials[14-16]with special photoelectric properties. A design of a compact near edge X-ray absorption spectrometer under grazing incidence conditions to study the NEXAFS spectrum of organic material carbon(1s) is presented, based on a grazing incidence light path, using a small laser-produced plasma source. In addition, the resolution of the spectrometer and the fitting allowance of components have been analyzed.

    2 X射線吸收譜儀設(shè)計

    Design of the X-ray absorption spectrometer

    碳的近邊吸收精細結(jié)構(gòu)在280~320 eV的能量范圍內(nèi),對應(yīng)波長范圍為3.8~4.4 nm,為了研究碳的譜線,要求譜儀在3~5 nm波段工作。碳的內(nèi)層電子從1s軌道躍遷到外層的未占分子軌道引起的吸收峰的典型能量寬度為0.5 eV[11],為了能準(zhǔn)確反映碳的1s NEXAFS譜的特征,譜儀在4.4 nm處的分辨率須在600以上。本文據(jù)此要求展開設(shè)計。

    The corresponding wavelength range of the near edge absorption fine structure of carbon is 3.8-4.4 nm within the energy range of 280-320 eV. In order to study the spectrum of carbon, the spectrometer is required to work at 3-5 nm. The typical energy width of the absorption peak caused by the transition of the inner electrons of carbon from 1s orbital to the outer unoccupied molecular orbital is 0.5 eV[11]. In order to accurately reflect the features of the NEXAFS spectrum of carbon(1s), the resolution of the spectrometer shall be over 600 at 4.4 nm. In this paper, the spectrometer has been designed based on above requirements.

    2.1 譜儀結(jié)構(gòu)設(shè)計

    Spectrometerstructuredesign

    本文采用攝譜法設(shè)計近邊X射線吸收譜儀,光源產(chǎn)生的“白光”先經(jīng)過樣品再分光,然后利用一維或二維探測器測定通過樣品前后的所有波長光的強度,從而獲得吸收譜,它能同時獲得所有波長光的強度,無需掃描,還可以做瞬態(tài)光譜分析。

    The near edge X-ray absorption spectrometer has been designed using the spectrography in this paper. The “white lights” generated by the light source pass through the sample and then are split. Later on, the intensity of lights with all wavelengths before and after passing through the sample is measured with a 1D or 2D detector so as to obtain the absorption spectrum. With the spectrometer, the intensity of lights with all wavelengths can be obtained simultaneously without scanning, and a transient spectrum analysis can also be made.

    設(shè)計的掠入射式近邊X射線吸收譜儀結(jié)構(gòu)示意圖如圖1所示,系統(tǒng)由氣體激光等離子體光源、樣品、狹縫、光柵和CCD組成。光源以氪氣作為靶材,經(jīng)過濾光產(chǎn)生波長2~6 nm的連續(xù)譜軟X射線,掠入射到樣品表面,反射光經(jīng)光柵分光,再由CCD測定各波長射線的強度,結(jié)合光源的譜線即可得到包含了吸收信息的反射譜。

    The sketch of the structure of the designed near edge X-ray absorption spectrometer under grazing incidence conditions is shown in Fig.1. The system consists of gas laser plasma source, sample, slit, grating and CCD(camera). Krypton is used as the target light source. 2-6 nm continuous spectral soft X-rays are generated through filtering and they are of grazing incidence to the sample surface. The reflected lights are split by the grating, and then the intensity of rays with various wavelengths is measured using the CCD(camera). The reflectance spectrum containing absorption information can be obtained according to the spectral line of the light source.

    圖1 掠入射式X射線吸收譜儀示意圖 Fig.1 Sketch of the designed X-ray absorption spectrometer under grazing incidence conditions

    菲涅耳公式給出了反射率與折射率間的關(guān)系,由于存在吸收,物質(zhì)對X射線的折射率不再是實數(shù),而是與吸收有關(guān)的復(fù)數(shù)形式n=1-δ-iβ,其中1-δ表示色散,β表示吸收,由β可以直接得到線吸收系數(shù)μ=4πβ/λ,因此反射率同樣包含吸收信息。將復(fù)折射率代入菲涅耳公式,可分別得到掠入射時p偏振和s偏振的X射線反射率,圖2為δ=0.001時不同吸收下反射率隨入射角的變化曲線,比較不同偏振光的反射率可知,無論吸收強弱,兩種偏振光反射率近似相等,因此,總反射率可以用s偏振光的反射率近似表示:

    Fresnel formula gives the relationship between reflectivity and refractive index. Due to existence of absorption, the refractive index of substances to X-ray is not a real number but a complex number related to absorption,i.e.n=1-δ-iβ, where 1-δdenotes dispersion andβdenotes absorption. The linear absorption coefficient can be directly obtained fromβ,i.e.μ=4πβ/λ. Therefore, reflectivity also contains absorption information. Substitute complex refractive index into Fresnel formula to obtain p-polarized X-ray reflectivity and s-polarized X-ray reflectivity under grazing incidence conditions respectively. Fig.2 is the curve of variation of reflectivity with incidence angle at different absorption intensity in case ofδ=0.001. According to the comparison of reflectivity of different polarized lights, in spite of absorption intensity, the reflectivity of two polarized lights is approximately equal, so the total reflectivity can be expressed approximately in the reflectivity of s-polarized light.

    (1)

    式中,φ是掠入射角,可以看出,反射率R(E)是δ(E)和β(E)的函數(shù),E為光子能量,利用公式(1)結(jié)合數(shù)據(jù)庫CXRO[17]中得到的δ(E)可以從測得的反射率譜線中提取出NEXAFS譜。

    Whereφis grazing incidence angle. It can be seen that reflectivityR(E) is the function ofδ(E) andβ(E), where E is photon energy. NEXAFS spectrum can be extracted from the measured reflectivity spectral line using formula (1) in combination withδ(E) obtained from the database CXRO[17].

    從圖2可以看出,反射率總是隨掠入射角的增大而減小,當(dāng)掠入射角增大到臨界角φc,低吸收的反射率迅速下降,這個角即為全反射臨界角。為了使反射率譜線能清晰反映吸收的變化,譜儀的掠入射角需小于樣品的全反射臨界角,考慮到有機物在碳的吸收邊4.4 nm附近的全反射臨界角約為3°,因此本文設(shè)計的譜儀取2°掠入射。

    As shown in Fig.2, reflectivity always decreases as grazing incidence angle increases. When grazing incidence angle increases to the critical angleφc, the reflectivity at low absorption intensity decreases rapidly. This angle is a critical angle of total reflection. In order that the reflectivity spectral line can clearly reflect absorption variation, the grazing incidence angle of the spectrometer would be less than the sample′s critical angle of total reflection. In view of the fact that the critical angle of total reflection of organic substances is about 3° near the carbon's absorption edge of 4.4 nm, the grazing incidence angle of the spectrometer designed in this paper is taken as 2°.

    圖2 反射率隨掠入射角的變化 Fig.2 Reflectivity as a function of grazing incidence angle

    2.2 光柵選型

    Gratingselection

    分光元件對譜儀的性能具有決定性作用。普通的平面光柵分辨能力較差,無法滿足X射線波段的高分辨率要求,如果增加聚焦鏡,會降低系統(tǒng)的光能利用率。常規(guī)的凹面等間距光柵具有分光和聚焦作用,但為使像差最小必須采用羅蘭圓結(jié)構(gòu),不能用平面探測器采集。因此,本文使用矯正像差的全息變柵距凹球面光柵,既能同時實現(xiàn)分光和聚焦,又具有平場特性,便于使用面陣型CCD接收。變柵距凹面光柵的原理示意圖如圖3所示,其中x軸為光柵中心法線方向,y軸為光柵中心切線方向,α為入射角,β為衍射角,r為入射臂長,r′為出射臂長。

    The light splitting element plays a decisive role in the performance of the spectrometer. The resolution capability of an ordinary plane grating is poor and cannot meet the high resolution requirements of X-ray wavelengths. In case of adding focusing mirrors, the system′s efficiency of light energy utilization will be reduced. The conventional concave evenly-spaced grating has functions such as light splitting and focusing, but to minimize aberration, Rowland circle structure must be adopted, and a plane detector cannot be used in acquisition. Therefore, the aberration-corrected holographic varied line-space concave spherical grating is used in this paper, which can achieve both light splitting and focusing and also has flat field characteristics, for convenience of using the area array type CCD to receive

    information. The schematic diagram of the aberration corrected flat-field grating is shown in Fig.3, wherexaxis is the central normal direction of the grating,yaxis is the central tangent direction of the grating,αis incidence angle,βis diffraction angle,ris incidence arm length, andr′ is emergence arm length.

    圖3 變柵距凹面光柵原理圖 Fig.3 Schematic diagram of the aberration corrected flat-field grating

    利用費馬原理[18]可以得到光柵色散方程和色散方向的聚焦方程分別為:

    Based on Fermat principle[18], the obtained grating′s dispersion equation and focusing equation in dispersion direction are respectively as follows:

    d0(sinα+sinβ)=mλ,

    (2)

    (3)

    式中,d0為光柵中心的刻線寬度,也稱為公稱線寬,R為光柵基底的曲率半徑,b2為光柵線密度參數(shù),選擇合適的值可以使光柵聚焦面近似為一平面。

    Whered0is the scale line width of grating center, also called nominal line width;Ris the radius of curvature of grating substrate;b2is the linear density parameter of grating. By selecting appropriate values, the focusing surface of the grating can be approximately a plane.

    本文選取Shimadzu的30-001型光柵,該光柵公稱線密度n02 400線/mm,工作波長范圍1~6 nm,入射臂長237 mm,入射角88.65°。 圖4給出了該光柵不同入射角對應(yīng)的聚焦曲線,坐標(biāo)系定義與圖3中一致,光柵參數(shù)來自于文獻[19]。 可以看出,入射角88.65°時,光柵中心到探測面距離D0為235 mm。不同入射角的聚焦曲線不同,但是都可以擬合成直線,因此可以根據(jù)需要改變光柵的使用結(jié)構(gòu)參數(shù)。

    Shimadzu 30-001 grating is selected. The parameters of the grating are the following: nominal linear densityn0is 2 400 lines/mm; wavelength range is 1-6 nm; incidence arm length is 237 nm, and incidence angle is 88.65°. Fig.4 shows the focusing curves at different incidence angles, where the coordinate system definition is in line with that in Fig.3, and grating parameters come from the reference [19]. As shown in Fig.4, when the incidence angle is 88.65°, the distanceD0from the grating center to the detection surface is 235 mm. Focusing curves at different incidence angles are different, but all of them can be fitted into straight lines, so the structure parameters of the grating can be changed as needed.

    圖4 不同入射角對應(yīng)的聚焦曲線,紅線表示聚焦曲線,黑色虛線表示其擬合直線,綠線表示不同波長 Fig.4 Focusing curves and fitting straight lines at different incidence angles. The red lines represent the focus curves, the black dashed lines are straight fitting lines and the green lines are different wavelengths

    2.3 裝配方案優(yōu)化

    Assemblyschemeoptimization

    光柵常規(guī)的裝配方案是CCD平面與光柵中心的切平面垂直,如圖5(a)所示,這樣的方案在實際使用中存在很大的困難,一方面,入射角的精度要求太高,需要借助高精度的調(diào)整機構(gòu)和測量裝置反復(fù)調(diào)試來保證;另一方面,CCD與光柵聯(lián)系緊密,調(diào)整光柵姿態(tài)時,CCD也必須相應(yīng)調(diào)整,提高了調(diào)整的難度。

    The conventional grating assembly scheme is that the CCD plane is vertical to the tangent plane of the grating center, as shown in Fig.5. Such scheme is very difficult in an actual application. On one hand, there are too high requirements for the incidence angle precision, and it can be guaranteed with the aid of a high precision adjusting mechanism and measuring device. On the other hand, CCD is closely linked with the grating. When the grating attitude is adjusted, CCD must be adjusted accordingly, thereby increasing the adjustment difficulty.

    圖5 光柵的不同使用結(jié)構(gòu) Fig.5 Structures of the grating (a)the conventional scheme, (b)the optimized scheme

    為了可以分開獨立調(diào)整光柵和CCD,我們以CCD平面與入射光線方向垂直作為目標(biāo)對裝配結(jié)構(gòu)進行優(yōu)化,如圖5(b)所示,這樣得到的方案下,CCD的傾角不再依賴光柵,從而可以先安裝調(diào)整好CCD再調(diào)節(jié)光柵,在真空中只需要轉(zhuǎn)動光柵,使特定波長的譜線的像最窄,就可以獲得較高的安裝精度。入射角α取88.6°進行設(shè)計,利用公式(2)和公式(3),以聚焦曲線的擬合直線與入射光線方向垂直為目標(biāo),獲得了對應(yīng)的最佳入射臂長r和光柵中心到CCD探測面的距離D,結(jié)果見表1。這樣在安裝時就只有光柵需要在真空中調(diào)整,同時也降低了入射角的調(diào)整難度。

    In order that the grating and CCD can be adjusted separately, the assembly structure has been optimized by aiming at making the CCD plane be vertical to the incident ray direction, as shown in Fig.5(b). In such scheme obtained, the dip angle of the CCD doesn't rely on the grating any longer, so that the CCD can be firstly installed and adjusted well and then the grating is adjusted. High installation precision can be obtained by only turning the grating in vacuum to make the image of the spectral line of the specific wavelength be the narrowest. The incidence angleαis taken as 88.6° in the design. Using formulas (2) and (3) and aiming at making the fitting straight line of the focusing curve vertical to the incident ray direction, the corresponding optimum incidence arm lengthrand distance D from the grating center to the CCD detection surface have been obtained. The result is shown in Tab.1. Thus, only the grating needs to be adjusted in vacuum during installation, which also reduces the difficulty in incidence angle adjustment.

    表1 優(yōu)化的裝配方案參數(shù)

    3 分辨率

    Resolution

    分辨率是光譜類儀器的重要指標(biāo)。本文設(shè)計的譜儀的分辨率主要受入射狹縫的寬度S1、光柵的衍射極限和像差、CCD像元尺寸S2等多項因素的影響,狹縫寬度和光柵性能決定了單色波長譜線的半高寬,像元尺寸則限制了譜儀的極限分辨率。

    Resolution is an important index of an optical spectrum instrument. The resolution of the spectrometer designed in this paper is affected mainly by multiple factors such as entrance slit widthS1, grating′s diffraction limit and aberration, CCD pixel sizeS2,etc. Slit width and grating performance decide the FWHM of monochromatic wavelength spectral line, and pixel size limits the limiting resolution of the spectrometer.

    由光柵方程結(jié)合幾何關(guān)系可得,光柵在探測面上的線色散為:

    According to the grating equation coupled with the geometrical relationship, the linear dispersion of the grating on the detection surface can be obtained as follows:

    (4)

    若已知某波長的光譜像的半高寬FWHM,則可以得到該波長的線寬為:

    If the FWHM of the spectral image at a wavelength is known, the line width of this wavelength can be obtained as follows:

    (5)

    利用光線追跡[20]可以獲取特定波長的譜線在探測面上的光譜像,從而綜合分析入射狹縫寬度和光柵性能的影響。狹縫寬度設(shè)為100 μm,入射臂長為270 mm,入射角為88.6°,光譜探測面放置在D=234 mm處,令光線在入射范圍內(nèi)隨機生成,可以模擬獲得探測面上的點列圖。通過統(tǒng)計寬度方向上各個像素內(nèi)的光線數(shù)量,得到光強統(tǒng)計分布圖,對光強分布進行高斯擬合,求出半高寬,即可利用公式(5)計算線寬。圖6為4.4 nm波長的譜線光線追跡獲得的點列圖、統(tǒng)計直方圖以及高斯擬合曲線,半高寬FWHM即像的寬度為13.8 μm,對應(yīng)線寬為0.003 5 nm。圖中橫坐標(biāo)表示譜線的像到入射光線的距離,對應(yīng)于圖5(b)中的長度l。

    The spectral image of the spectral line at a specific wavelength on the detection surface can be obtained using the ray tracing method[20], thus comprehensively analyzing the influence of entrance slit and grating performance. The spot diagram on the detection surface can be obtained on the assumption that the slit width is 100 μm, the incidence arm length is 270 nm, the incidence angle is 88.6°, the spectral detection surface is placed atD=234 mm and rays are generated randomly within the incidence range. The statistical distribution chart of light intensity is obtained from the statistical analysis of rays of each pixel in the width direction. The FWHM is calculated through Gaussian fitting of the light intensity distribution, and then the line width can be calculated using formula (5). Fig.6 shows the spot diagram, histogram and Gauss fitting curve obtained using ray tracing at 4.4 nm. The FWHM i.e. image width is 13.8 μm, and the corresponding line width is 0.003 5 nm. In the figure, the abscissa denotes the distance from the spectral line image to the incident ray, which is corresponding with the lengthlin Fig.5(b).

    圖6 4.4 nm波長的光線追跡結(jié)果 Fig.6 The result of ray tracing at 4.4 nm (a)Spot diagram, (b)Histogram, (c)Gauss fitting curve

    受探測器像元尺寸的限制,光譜儀的分辨率往往不能直接由譜線線寬決定。根據(jù)奈奎斯特抽樣定理,為了能真實反映信號特征,采樣頻率應(yīng)大于信號頻率的兩倍,由公式(4)可以得到單個像元對應(yīng)的譜線線寬ΔλS2,則譜儀極限分辨率為Remax=λ/2ΔλS2。像元寬度為13 μm,4.4 nm的半高寬小于像元尺寸的兩倍,因此設(shè)計的譜儀可以實現(xiàn)極限分辨率,4.4 nm處分辨率為666,對應(yīng)線寬0.006 6 nm。使用像元數(shù)1 024的CCD,譜儀工作范圍超過3 nm,滿足設(shè)計要求。

    Limited by the pixel size of the detector, the resolution of the spectrometer cannot be determined directly by the spectral line width in general. According to Nyquist sampling theorem, the sampling frequency would be larger than twice of the signal frequency in order to truly reflect signal features. According to formula (4), the spectral line width corresponding with a single pixel can be obtained, and then the limiting resolution of the spectrometer isRemax=λ/2ΔλS2. The pixel width is 13 μm, and the FWHM of 4.4 nm is less than twice of the pixel size, so the designed spectrometer can achieve the limiting resolution, its resolution is 666 at 4.4 nm, and the corresponding line width is 0.006 6 nm. The CCD with 1 024 pixels is used and the wavelength range of the spectrometer is over 3 nm, which meets the requirements of the design.

    基于以上分析,本文設(shè)計的掠入射式近邊X射線吸收譜儀的參數(shù)如表2所示。

    表2 掠入射式近邊X射線吸收譜儀設(shè)計參數(shù)

    According to the above analysis, the parameters of the near-edge X-ray absorption spectrometer under grazing incidence conditions designed in this paper are shown in Tab.2.

    4 公差分析及裝調(diào)方案設(shè)計

    Tolerance analysis and assembly scheme design

    根據(jù)前文的分析,為了使譜儀實現(xiàn)極限分辨率,譜線的半高寬應(yīng)小于兩個像元的尺寸,即26 μm,而半高寬主要取決于入射狹縫、光柵和CCD之間的相對位置。圖7給出了各參數(shù)的偏差對4.4 nm波長的半高寬的影響,可以看出,入射臂長r的誤差δr對半高寬的影響幾乎可以忽略,D、θ和α的偏差主要表現(xiàn)為向系統(tǒng)引入離焦像差,而半高寬對入射角α的變化最為敏感。綜合考慮各參數(shù)的作用,結(jié)合機械結(jié)構(gòu)的調(diào)整能力,確定r、D、θ、α的公差分別為±1 mm、±0.1 mm、±0.5°、±0.04°,譜線在極限誤差下的半高寬為24.8 μm,滿足設(shè)計要求。

    圖7 各參數(shù)(r、D、θ、α)的誤差對4.4 nm單色譜線的半高寬的影響 Fig.7 Influence of the error of each parameter on the FWHM at 4.4 nm (a)r, (b)D, (c)θ, (d)α

    According to the previous analysis, in order to achieve the limiting resolution of the spectrometer, the FWHM of spectra line would be less than the size of two pixels,i.e. 26 μm. The FWHM depends mainly on the relative position among the entrance slit, grating and CCD. Fig.7 shows the influence of the error of each parameter on the FWHM at 4.4 nm. As shown in the figure, the influence of the errorδrof the incidence arm lengthron the FWHM can be neglected, the error ofD,θandαis manifested mainly as the defocus aberration introduced to the system, and the FWHM is the most sensitive to the variation of the incidence angleα. Comprehensively considering the role of each parameter in combination with the adjusting capacity of the mechanical structure, the tolerance ofr,D,θandαis determined to be ±1 mm, ±0.1 mm, ±0.5° and ±0.04° respectively, and the FWHM of spectral line at the limiting error is 24.8 μm, which meets the requirements of the design.

    公差分析結(jié)果表明,在本文優(yōu)化的方案下,r、D和θ可以在大氣環(huán)境中使用常規(guī)方法測量并調(diào)整到位,在真空環(huán)境中利用高精度電動轉(zhuǎn)臺連續(xù)改變α,使氮氣等離子體發(fā)出的2.878 7 nm譜線的半高寬最小,從而可以滿足入射角的高精度要求。

    According to the tolerance analysis result, using the optimized scheme in this paper,r,Dandθcan be measured in atmospheric environment with a conventional method and well adjusted. In addition,αis changed continuously in vacuum environment using a high precision electric rotary table so as to minimize the FWHM of the 2.878 7 nm spectral line emitted by nitrogen plasma, which can thus meet the high precision requirements of incidence angle.

    5 分辨率測試與波長標(biāo)定

    Resolution test and wavelength calibration

    圖8展示了搭建完成的小型掠入射式近邊X射線吸收譜儀。光譜儀工作在10-4Pa真空環(huán)境下。沿著光路方向(在圖中標(biāo)注光源、各個腔體),3個真空腔體分別為光源室、樣品室和光柵室,激光聚焦到噴出的氣體團上形成等離子體,產(chǎn)生X射線輻射輸出,經(jīng)Ti膜后照射到樣品表面,Ti膜用于過濾帶外光。為了結(jié)構(gòu)緊湊,入射狹縫安置在樣品室中,CCD通過波紋管與光柵室相連,以便通過調(diào)整機構(gòu)微調(diào)CCD位置。

    Fig.8 shows the well-erected compact near edge X-ray absorption spectrometer under grazing incidence conditions. The spectrometer works in 10-4Pa vacuum environment. Along the light path direction(light source and each chamber marked in the figure), the three vacuum chambers are light source chamber, sample chamber and grating chamber respectively. Laser is focused onto the ejected gas clumps to form plasma and generate X-ray radiation output. After passing through the Ti membrane, rays shine on the sample surface. The Ti membrane is used to filter out-of-band lights. In order to achieve a compact structure, the entrance slit is placed in the sample chamber, and the CCD is connected with the grating chamber via the corrugated pipe, for convenience of micro-adjusting the CCD position through the adjusting mechanism.

    圖8 光譜儀實物圖 Fig.8 Picture of the spectrometer

    氮氣作為激光等離子體光源靶材對光譜儀分辨率進行測試,圖9為實驗測得的光譜圖。可以看出,氮氣在2~5 nm波段的譜線均清晰可見,波長2.478 nm和2.49 nm兩條譜線也能明顯區(qū)分。對這兩個光譜峰進行高斯擬合得到曲線C1和C2,曲線C1的半高寬FWHM為1.9,不足兩個像元,表明搭建的光譜儀可實現(xiàn)極限分辨,滿足設(shè)計指標(biāo)。

    圖9 氮氣等離子體譜線 Fig.9 Spectrum of N2 plasma

    The resolution of the spectrometer has been tested using nitrogen as the laser plasma source target. Fig.9 shows the spectrogram obtained from the test. It can be seen that the spectral lines of nitrogen at 2-5 nm are clearly visible and the two spectral lines at 2.478 nm and 2.49 nm can also be identified obviously. The curves C1 and C2 are obtained from Gauss fitting of the two spectral peaks. The HWHM of curve C1 is 1.9 that is less than two pixels, indicating that the erected spectrometer can achieve the limiting resolution and the design index.

    采用參數(shù)擬合法[19]進行波長標(biāo)定,模型如式(6)所示:

    Wavelength calibration is performed using the parameter fitting method[19]. The model is shown in formula (6).

    (6)

    式中,各參數(shù)的定義參考圖5(b),N為CCD像素的位置,上邊緣對應(yīng)N為0的位置,n0表示光柵的公稱線密度。表3給出了像素位置對應(yīng)的實際波長和標(biāo)定波長,結(jié)果顯示波長標(biāo)定的誤差小于0.001 nm,光譜儀實際工作波長范圍2~5 nm。

    Refer to Fig.5(b) for the definition of each parameter in the above formula. N is the position of CCD pixel, the upper edge is the position atN=0, andn0denotes the nominal linear density of the grating. Tab.3 shows the actual wavelength and calibration wavelength at pixel positions. The results show that the wavelength calibration error is less than 0.001 nm and the actual wavelength range of the spectrometer is 2-5 nm.

    表3 波長標(biāo)定結(jié)果

    利用參數(shù)擬合法標(biāo)定波長可以反求出系統(tǒng)各參數(shù)的實際值,并與理論設(shè)計值進行比較,結(jié)果如表4所示,可見各參數(shù)的實際值與設(shè)計值基本吻合,偏差均滿足公差分配要求。

    The actual value of each parameter of the system can be calculated through wavelength calibration with the parameter fitting method. The actual value is compared with the theoretical design value. The result is shown in Tab.4. As shown in the table, the actual value of each parameter is basically consistent with the design value, and all deviations meet the tolerance distribution requirements.

    表4 光學(xué)系統(tǒng)參數(shù)設(shè)計值與實際值比較

    6 結(jié) 論

    Conclusion

    采用激光等離子體光源、球面變柵距光柵和面型CCD設(shè)計了一臺用于研究有機物的碳1s NEXAFS譜掠入射式近邊X射線吸收譜儀,掠入射角取2°。為了方便調(diào)節(jié)光學(xué)元件的相對位置和姿態(tài),以探測面與入射光線垂直為目標(biāo)對安裝參數(shù)進行了優(yōu)化,得到了光柵入射角88.6°時的安裝方案,入射臂長270 mm,光柵中心到CCD探測面垂直距離234.0 mm。利用光線追跡的方法模擬了譜儀的光譜,縫寬100 μm時光譜儀在4.4 nm處的分辨率達到666,可以滿足研究碳1s NEXAFS譜的要求。分析了各裝配參數(shù)的誤差對4.4 nm處分辨率的影響,確定了r、D、θ、α的公差分別為±1 mm、±0.1 mm、±0.5°、±0.04°,據(jù)此設(shè)計了譜儀的裝調(diào)方案。最后通過測量氮氣等離子體光譜,對光譜儀性能進行了測試,結(jié)果顯示,譜儀各項性能滿足設(shè)計要求。

    In order to study the NEXAFS spectrum of the organic material carbon(1s), we design a near edge X-ray absorption spectrometer under grazing incidence conditions using a laser-produced plasma source, an aberration corrected flat-field grating and a planar CCD. The grazing incidence angle of the spectrometer is taken as 2°. In order to conveniently adjust the relative position and attitude of optical elements, the installation parameters have been optimized aiming at making the detection surface vertical to the incident ray direction. The optimized installation scheme where the incidence angle of the grating is 88.6° has been obtained. The incidence arm length is 270 mm, and the vertical distance from the grating center to the CCD detection surface is 234.0 mm. Using the ray tracing method, the spectrum of the spectrometer has been simulated. When the slit width is 100 μm, the resolution of the spectrometer reaches 666 at 4.4 nm, which can meet the requirements of research on the NEXAFS spectrum of carbon(1s). The influence of the error of each assembly parameter on the resolution at 4.4 nm has been analyzed, and the tolerance ofr,D,θandαhas been determined to be ±1 mm, ±0.1 mm, ±0.5° and ±0.04°, respectively. Based on above parametors, the assembly scheme of the spectrometer has been designed. Finally the performance of the spectrometer has been tested by measuring nitrogen plasma spectrum. The results show that all performance indexes of the spectrometer meet the design requirements.

    參考文獻:

    [1]馬禮敦.X射線吸收光譜及發(fā)展[J].上海計量測試,2007,34(6):2-11.

    MA L D. X-ray absorption Spectroscopy and its developments[J].ShanghaiMeasurement&Testing,2007,34(6):2-11.(in Chinese)

    [2]GROOT D. XANES spectra of transition metal compounds[J].JournalofPhysics:ConferenceSeries,2009,190(1):111-116.

    [3]WEISS K,WOELL C,JOHANNSAMANN D. Near-surface molecular orientation in polymeric alignment layers:a NEXAFS investigation[J].ProceedingsofSPIE,1999,3800:104-111.

    [4]潘宵.聚合物光電器件中金屬/聚合物界面結(jié)構(gòu)與性質(zhì)的研究[D].合肥:中國科學(xué)技術(shù)大學(xué),2015.

    PAN X. The structures and properties of metal/polymer interfaces in polymer-based photoelectronic devices[D]. Hefei:University of Science and Technology of China,2015.(in Chinese)

    [5]李輝,高強,王帥,等.同步輻射軟X射線近邊吸收譜方法研究長期施肥對黑土有機氮官能團的影響[J].光譜學(xué)與光譜分析,2015(7):2038-2042.

    LI H,GAO Q,WANG SH,etal.. Effect of long-term fertilization on organic nitrogen functional groups on black soil as revealed by synchrotron-based X-ray absorption near-edge structure spectroscopy[J].SpectroscopyandSpectralAnalysis,2015(7):2038-2042.(in Chinese)

    [6]BRAUN A. Carbon speciation in airborne particulate matter with C(1s) NEXAFS spectroscopy[J].JournalofEnvironmentalMonitoringJem,2005,7(11):1059-65.

    [7]NOV KOV E,MITREA G,PETH C,etal.. Solid supported multicomponent lipid membranes studied by x-ray spectromicroscopy[J].Biointerphases,2008,3(2):FB44-FB54.

    [8]YODA O,MIYASHITA A,MURAKAMI K,etal.. Time-resolved X-ray absorption spectroscopy apparatus using laser plasma as an X-ray source[J].ProceedingsofSPIE,1991,1503:463-466.

    [9]NAKANO H,GOTO Y,LU P,etal.. Time-resolved soft X-ray absorption spectroscopy of silicon using femtosecond laser plasma X-rays[J].AppliedPhysicsLetters,1999,75(16):2350-2352.

    [10]BECK M,VOGT U,WILL I,etal.. A pulse-train laser driven XUV source for picosecond pump probe experiments in the water window[J].OpticsCommunications,2001,190(1-6):317-326.

    [11]VOGT U,WILHEIN T,STIEL H,etal.. High resolution X-ray absorption spectroscopy using a laser plasma radiation source[J].ReviewofScientificInstruments,2004,75(11):4606-4609.

    [12]PETH C,BARKUSKY F,SEDLMAIR J,etal.. Near-edge X-ray absorption fine structure measurements using a laser plasma XUV source[J].JournalofPhysics:ConferenceSeries,2009,186(1):012032.

    [13]SEDLMAIR J,GEBER S,PETH C,etal.. NEXAFS spectroscopy with a laser plasma X-ray source on soil samples[J].JournalofPhysics:ConferenceSeries,2009,186(1):012034.

    [14]薛守慶,薛兆民.二次摻雜聚吡咯/聚噻吩膜的制備及其光電性能[J].發(fā)光學(xué)報,2016,37(9):1124-1129.

    XUE SH Q,XUE Z M. Preparation and anti-corrosive performance of Ppy/PTh composites redoped with zinc phosphate[J].ChineseJournalofLuminescence,2016,37(9):1124-1129.

    [15]鄒鳳君,范思大,謝強,等.摻雜石墨烯量子點對P3HT:PCBM太陽能電池性能的影響[J].發(fā)光學(xué)報,2016,37(9):1082-1089.

    ZOU F J,FAN S D,XIE Q,etal.. Effect of doping graphene quantum dots on the performance of P3HT:PCBM Solar Cells[J].ChineseJournalofLuminescence,2016,37(9):1082-1089.

    [16]彭博,曹亞鵬,胡煜峰,等.P3HT/PMMA雙層聚合物電雙穩(wěn)器件的研究[J].發(fā)光學(xué)報,2016,37(9):1090-1096.

    PENG B,CAO Y P,HU Y F,etal.. Polymer bistable devices based on poly(3-hexylthiophene)/ poly(methylmethacrylate) bilayer films[J].ChineseJournalofLuminescence,2016,37(9):1090-1096.

    [17]ANDERSON C. Center for X-Ray Optics:http://www-cxro.lbl.gov/.

    [18]HARADA T,KITA T. Mechanically ruled aberration-corrected concave gratings[J].AppliedOptics,1980,19(23):3987-3993.

    [19]杜學(xué)維.凹面變線距光柵的二維線密度分布測試及軟X射線平場光譜儀的研制[D].合肥:中國科學(xué)技術(shù)大學(xué),2013.

    DU X W. Measurement of groove density 2D distribution of concave VLS grating and construction of a soft X-ray flat field spectrograph[D]. Hefei:University of Science and Technology of China,2013.(in Chinese)

    [20]LAI B,CERRINA F. SHADOW:a synchrotron radiation ray tracing program[J].NuclearInstruments&MethodsinPhysicsResearch,1986,246(1-3):337-341.

    猜你喜歡
    譜儀入射角譜線
    一般三棱鏡偏向角與入射角的關(guān)系
    一種磁共振成像譜儀數(shù)字化發(fā)射系統(tǒng)設(shè)計
    新型X波段多功能EPR譜儀的設(shè)計與性能
    基于HITRAN光譜數(shù)據(jù)庫的合并譜線測溫仿真研究
    基于Casper和Simulink的射電譜儀信號處理系統(tǒng)設(shè)計與實現(xiàn)
    預(yù)制圓柱形鎢破片斜穿甲鋼靶的破孔能力分析*
    鐵合金光譜譜線分離實驗研究
    電子測試(2018年11期)2018-06-26 05:56:00
    用經(jīng)典定理證明各向異性巖石界面異常入射角的存在
    鍶原子光鐘鐘躍遷譜線探測中的程序控制
    藥芯焊絲GMAW電弧光譜的研究
    機械工程師(2014年6期)2014-12-23 06:44:22
    操美女的视频在线观看| 国产精品久久久久久精品电影小说| 美女高潮到喷水免费观看| 欧美精品高潮呻吟av久久| 精品国产一区二区三区四区第35| 老司机深夜福利视频在线观看 | 国产黄色免费在线视频| 在线观看国产h片| 欧美日韩av久久| 亚洲国产精品国产精品| 97精品久久久久久久久久精品| 一级毛片电影观看| www.精华液| av又黄又爽大尺度在线免费看| 精品熟女少妇八av免费久了| 亚洲国产av影院在线观看| 日本a在线网址| 欧美日韩福利视频一区二区| 91精品伊人久久大香线蕉| 久久精品久久久久久久性| av视频免费观看在线观看| 亚洲七黄色美女视频| 一本—道久久a久久精品蜜桃钙片| 王馨瑶露胸无遮挡在线观看| 乱人伦中国视频| 成人免费观看视频高清| 美女主播在线视频| 91精品国产国语对白视频| 亚洲成人免费电影在线观看 | 色视频在线一区二区三区| 亚洲精品成人av观看孕妇| 国产主播在线观看一区二区 | 热re99久久精品国产66热6| 热99久久久久精品小说推荐| 亚洲精品日韩在线中文字幕| 久久人人爽av亚洲精品天堂| 飞空精品影院首页| 欧美日本中文国产一区发布| 久久精品人人爽人人爽视色| 18禁裸乳无遮挡动漫免费视频| 国产免费一区二区三区四区乱码| 嫩草影视91久久| av有码第一页| 性少妇av在线| 99国产精品一区二区三区| 丝袜喷水一区| av网站免费在线观看视频| 大片电影免费在线观看免费| 国产亚洲av高清不卡| 两个人免费观看高清视频| 亚洲黑人精品在线| 成人18禁高潮啪啪吃奶动态图| 久久久久国产精品人妻一区二区| 久久av网站| 久久性视频一级片| 啦啦啦在线免费观看视频4| 美女视频免费永久观看网站| 19禁男女啪啪无遮挡网站| 亚洲天堂av无毛| 91老司机精品| 男人舔女人的私密视频| 香蕉丝袜av| 国产成人av教育| 多毛熟女@视频| 校园人妻丝袜中文字幕| 一级毛片我不卡| 亚洲精品一区蜜桃| 久久精品人人爽人人爽视色| 欧美日韩成人在线一区二区| 超色免费av| av线在线观看网站| 狠狠精品人妻久久久久久综合| 丝袜喷水一区| 亚洲激情五月婷婷啪啪| 男女边吃奶边做爰视频| 两个人看的免费小视频| 亚洲一卡2卡3卡4卡5卡精品中文| 欧美日韩视频精品一区| 成人黄色视频免费在线看| 亚洲国产av影院在线观看| 亚洲情色 制服丝袜| 侵犯人妻中文字幕一二三四区| 久久人人97超碰香蕉20202| 99久久人妻综合| 青春草视频在线免费观看| kizo精华| 久久久久精品人妻al黑| 免费看十八禁软件| xxxhd国产人妻xxx| 免费黄频网站在线观看国产| 亚洲精品自拍成人| www.熟女人妻精品国产| 欧美人与性动交α欧美软件| 亚洲国产最新在线播放| 人人妻人人添人人爽欧美一区卜| 美女福利国产在线| 免费一级毛片在线播放高清视频 | 午夜免费男女啪啪视频观看| 51午夜福利影视在线观看| 99热网站在线观看| 日日摸夜夜添夜夜爱| 一级黄片播放器| 久久久久久久大尺度免费视频| 黄色一级大片看看| 久久这里只有精品19| 校园人妻丝袜中文字幕| 久久国产亚洲av麻豆专区| 高清欧美精品videossex| 秋霞在线观看毛片| 亚洲国产日韩一区二区| 777米奇影视久久| 曰老女人黄片| 亚洲国产看品久久| 成人黄色视频免费在线看| 亚洲精品av麻豆狂野| 嫩草影视91久久| 你懂的网址亚洲精品在线观看| 啦啦啦在线观看免费高清www| 国产精品免费视频内射| 亚洲成人国产一区在线观看 | 日本五十路高清| 大陆偷拍与自拍| 十分钟在线观看高清视频www| 夜夜骑夜夜射夜夜干| 久久精品久久久久久久性| 国产淫语在线视频| 狠狠婷婷综合久久久久久88av| 精品一区二区三区四区五区乱码 | 欧美人与善性xxx| 国产熟女午夜一区二区三区| 2021少妇久久久久久久久久久| 久热这里只有精品99| 青草久久国产| 美国免费a级毛片| 搡老岳熟女国产| 亚洲黑人精品在线| 黄色a级毛片大全视频| 晚上一个人看的免费电影| 成在线人永久免费视频| 熟女少妇亚洲综合色aaa.| 国产黄色视频一区二区在线观看| 中文字幕人妻丝袜一区二区| 爱豆传媒免费全集在线观看| 下体分泌物呈黄色| 国产一区二区三区综合在线观看| 女人精品久久久久毛片| 夜夜骑夜夜射夜夜干| 亚洲 国产 在线| 精品久久久久久久毛片微露脸 | 亚洲色图 男人天堂 中文字幕| 在线观看免费高清a一片| 久久久国产欧美日韩av| 中文欧美无线码| 国产免费视频播放在线视频| 日本欧美视频一区| 中文字幕人妻丝袜制服| 18禁裸乳无遮挡动漫免费视频| 亚洲成人手机| 国产精品久久久人人做人人爽| 成人手机av| 久久精品国产综合久久久| 国产免费又黄又爽又色| 欧美精品一区二区免费开放| 亚洲一区中文字幕在线| 女人久久www免费人成看片| 精品久久蜜臀av无| 丰满饥渴人妻一区二区三| 亚洲人成77777在线视频| 亚洲av成人精品一二三区| av国产精品久久久久影院| 国产无遮挡羞羞视频在线观看| 亚洲第一青青草原| 男女下面插进去视频免费观看| 中文字幕人妻熟女乱码| 亚洲av电影在线观看一区二区三区| 亚洲午夜精品一区,二区,三区| 亚洲伊人色综图| 人妻一区二区av| 91国产中文字幕| 亚洲精品久久午夜乱码| 九色亚洲精品在线播放| 亚洲少妇的诱惑av| 亚洲黑人精品在线| 国产免费一区二区三区四区乱码| 男女床上黄色一级片免费看| 一本—道久久a久久精品蜜桃钙片| 99热全是精品| 色网站视频免费| 国产视频首页在线观看| 亚洲少妇的诱惑av| 麻豆国产av国片精品| 又黄又粗又硬又大视频| 一本一本久久a久久精品综合妖精| 亚洲国产av新网站| 国产精品国产三级国产专区5o| 国产男女超爽视频在线观看| 丰满迷人的少妇在线观看| 亚洲精品一区蜜桃| 男人操女人黄网站| 久热爱精品视频在线9| 黄色一级大片看看| 在线观看国产h片| av在线app专区| 视频在线观看一区二区三区| 国产成人精品久久二区二区免费| 午夜福利,免费看| 亚洲免费av在线视频| 侵犯人妻中文字幕一二三四区| 国产免费现黄频在线看| 国产人伦9x9x在线观看| 日韩 欧美 亚洲 中文字幕| 观看av在线不卡| 欧美国产精品va在线观看不卡| 高清视频免费观看一区二区| 免费av中文字幕在线| 三上悠亚av全集在线观看| 久久精品国产亚洲av涩爱| 亚洲欧洲国产日韩| 久久久久国产精品人妻一区二区| 久久久精品免费免费高清| 日本色播在线视频| 秋霞在线观看毛片| 国产福利在线免费观看视频| 好男人视频免费观看在线| 久久久欧美国产精品| 精品一区二区三区四区五区乱码 | 国产精品av久久久久免费| 久久午夜综合久久蜜桃| 国产免费又黄又爽又色| 亚洲国产av影院在线观看| 国产精品免费视频内射| 国产亚洲精品久久久久5区| 亚洲av电影在线观看一区二区三区| 精品亚洲成国产av| 国产成人一区二区三区免费视频网站 | 国产免费又黄又爽又色| 亚洲欧洲国产日韩| 秋霞在线观看毛片| 免费观看av网站的网址| 99久久99久久久精品蜜桃| 18禁国产床啪视频网站| 色综合欧美亚洲国产小说| 午夜精品国产一区二区电影| 一区二区三区精品91| 最近手机中文字幕大全| 女人久久www免费人成看片| 欧美精品av麻豆av| 久久狼人影院| 亚洲成国产人片在线观看| 老司机靠b影院| 纵有疾风起免费观看全集完整版| 久久精品国产综合久久久| 亚洲av美国av| 中文字幕最新亚洲高清| 久久精品aⅴ一区二区三区四区| 菩萨蛮人人尽说江南好唐韦庄| 亚洲成人免费电影在线观看 | 性色av一级| 亚洲欧美精品自产自拍| 丰满少妇做爰视频| 热99久久久久精品小说推荐| 99香蕉大伊视频| 天天躁日日躁夜夜躁夜夜| 国产又爽黄色视频| 少妇人妻久久综合中文| www.自偷自拍.com| 国产熟女午夜一区二区三区| 久久久久久免费高清国产稀缺| 欧美在线一区亚洲| www日本在线高清视频| 91精品三级在线观看| 熟女少妇亚洲综合色aaa.| 自线自在国产av| 国产精品国产三级专区第一集| 又黄又粗又硬又大视频| 国产精品av久久久久免费| 亚洲 欧美一区二区三区| 国产精品久久久人人做人人爽| av片东京热男人的天堂| 丝瓜视频免费看黄片| 男女边摸边吃奶| 脱女人内裤的视频| 日韩制服丝袜自拍偷拍| 久久九九热精品免费| 欧美日韩av久久| 一级毛片黄色毛片免费观看视频| 黑人猛操日本美女一级片| 日韩中文字幕欧美一区二区 | 成年女人毛片免费观看观看9 | 欧美日韩精品网址| 欧美激情极品国产一区二区三区| 久久久久视频综合| 丝袜美足系列| 乱人伦中国视频| 国产精品.久久久| 18禁裸乳无遮挡动漫免费视频| 三上悠亚av全集在线观看| 亚洲国产精品一区二区三区在线| 大片免费播放器 马上看| 亚洲,欧美,日韩| 国产精品欧美亚洲77777| 久久久国产欧美日韩av| 成人国产av品久久久| 啦啦啦在线免费观看视频4| 蜜桃在线观看..| 国产一区二区在线观看av| 黄色视频在线播放观看不卡| 亚洲av美国av| 操出白浆在线播放| 亚洲一区中文字幕在线| 夫妻性生交免费视频一级片| 啦啦啦在线观看免费高清www| 一二三四在线观看免费中文在| 久久狼人影院| 亚洲色图 男人天堂 中文字幕| 久久 成人 亚洲| 精品视频人人做人人爽| 久9热在线精品视频| 亚洲自偷自拍图片 自拍| 色94色欧美一区二区| 一级毛片女人18水好多 | 亚洲,一卡二卡三卡| 1024香蕉在线观看| 伦理电影免费视频| 久久精品aⅴ一区二区三区四区| 一级毛片 在线播放| 成年av动漫网址| 久久免费观看电影| 好男人视频免费观看在线| 巨乳人妻的诱惑在线观看| 免费观看av网站的网址| www.精华液| 飞空精品影院首页| 欧美人与性动交α欧美精品济南到| 国产精品国产三级国产专区5o| 久久免费观看电影| 亚洲欧美日韩另类电影网站| 亚洲精品日韩在线中文字幕| 午夜两性在线视频| 久久九九热精品免费| 一级黄色大片毛片| av网站免费在线观看视频| 亚洲精品日本国产第一区| 肉色欧美久久久久久久蜜桃| 免费在线观看视频国产中文字幕亚洲 | 天堂中文最新版在线下载| 国产在视频线精品| 久久人妻熟女aⅴ| 亚洲中文日韩欧美视频| 成人亚洲精品一区在线观看| 精品卡一卡二卡四卡免费| 国产亚洲欧美在线一区二区| 国产1区2区3区精品| 日韩,欧美,国产一区二区三区| 国产精品一区二区免费欧美 | 免费人妻精品一区二区三区视频| 亚洲精品一卡2卡三卡4卡5卡 | 中文字幕人妻丝袜一区二区| 伦理电影免费视频| 国产精品麻豆人妻色哟哟久久| 免费观看a级毛片全部| 国产精品久久久久久精品古装| 两性夫妻黄色片| 亚洲三区欧美一区| 91国产中文字幕| 亚洲精品在线美女| 制服诱惑二区| 久久久久久久大尺度免费视频| 如日韩欧美国产精品一区二区三区| 亚洲精品在线美女| 成人黄色视频免费在线看| 亚洲欧美激情在线| 国产精品国产三级专区第一集| 亚洲欧美日韩另类电影网站| 两性夫妻黄色片| 在线观看www视频免费| 亚洲五月婷婷丁香| 蜜桃国产av成人99| 欧美人与性动交α欧美精品济南到| 天堂俺去俺来也www色官网| 日韩大码丰满熟妇| 国产亚洲av高清不卡| 久久精品国产亚洲av高清一级| 国精品久久久久久国模美| 欧美变态另类bdsm刘玥| bbb黄色大片| 日韩制服丝袜自拍偷拍| 在线观看免费日韩欧美大片| 日韩免费高清中文字幕av| 久久亚洲精品不卡| bbb黄色大片| 精品国产超薄肉色丝袜足j| 成人手机av| 欧美亚洲日本最大视频资源| 少妇人妻 视频| av天堂在线播放| 亚洲av男天堂| 日韩 欧美 亚洲 中文字幕| 久9热在线精品视频| 国产无遮挡羞羞视频在线观看| 伊人亚洲综合成人网| 老司机亚洲免费影院| 久久国产精品大桥未久av| 欧美精品av麻豆av| 波多野结衣av一区二区av| 99香蕉大伊视频| 欧美成人精品欧美一级黄| 男女边摸边吃奶| 在线 av 中文字幕| 亚洲av美国av| 国产男女内射视频| 亚洲图色成人| 后天国语完整版免费观看| 久久国产精品影院| 一区二区三区精品91| 欧美成人午夜精品| 亚洲av日韩在线播放| 天天躁日日躁夜夜躁夜夜| 免费看不卡的av| 亚洲欧洲国产日韩| 亚洲五月色婷婷综合| 国产欧美日韩精品亚洲av| 国产激情久久老熟女| 丝袜喷水一区| 别揉我奶头~嗯~啊~动态视频 | 啦啦啦在线观看免费高清www| 日韩中文字幕欧美一区二区 | 日日夜夜操网爽| 国产日韩欧美亚洲二区| 久久精品成人免费网站| 9191精品国产免费久久| 国产男女超爽视频在线观看| 国产片特级美女逼逼视频| 婷婷色麻豆天堂久久| 亚洲av综合色区一区| 人人妻人人澡人人看| 国产日韩欧美亚洲二区| 免费久久久久久久精品成人欧美视频| 午夜福利,免费看| 亚洲精品av麻豆狂野| 精品国产一区二区三区久久久樱花| www日本在线高清视频| 电影成人av| 亚洲成人免费电影在线观看 | 精品亚洲成国产av| 国产亚洲午夜精品一区二区久久| 高清视频免费观看一区二区| 91精品国产国语对白视频| 亚洲九九香蕉| 精品福利观看| 免费观看a级毛片全部| 国产在线一区二区三区精| 国产深夜福利视频在线观看| 老司机午夜十八禁免费视频| 青春草视频在线免费观看| 国产精品一区二区在线不卡| 国产三级黄色录像| 国产精品熟女久久久久浪| 这个男人来自地球电影免费观看| 久久久久久人人人人人| 国产成人免费观看mmmm| 久久久精品免费免费高清| 国产成人av激情在线播放| 亚洲成色77777| 国产精品熟女久久久久浪| 国产黄色免费在线视频| 久久久久久久国产电影| 少妇的丰满在线观看| 考比视频在线观看| 亚洲色图综合在线观看| 免费观看av网站的网址| 亚洲精品成人av观看孕妇| av福利片在线| 午夜影院在线不卡| 久久国产精品人妻蜜桃| 亚洲成色77777| 在线 av 中文字幕| 两性夫妻黄色片| 午夜免费成人在线视频| √禁漫天堂资源中文www| 久久av网站| 午夜日韩欧美国产| cao死你这个sao货| 亚洲国产欧美日韩在线播放| 成年女人毛片免费观看观看9 | 婷婷丁香在线五月| 亚洲av美国av| av电影中文网址| 日韩一本色道免费dvd| 国产亚洲一区二区精品| 性少妇av在线| 国产xxxxx性猛交| 精品第一国产精品| 视频区欧美日本亚洲| 国产老妇伦熟女老妇高清| 只有这里有精品99| 黑人巨大精品欧美一区二区蜜桃| 国产男女内射视频| 看免费成人av毛片| 久久精品亚洲熟妇少妇任你| 欧美日韩成人在线一区二区| 亚洲国产精品国产精品| www.熟女人妻精品国产| 国产在线免费精品| 男人爽女人下面视频在线观看| 国产黄频视频在线观看| 在线观看人妻少妇| 成人影院久久| 精品久久久久久久毛片微露脸 | 飞空精品影院首页| 久久久久国产一级毛片高清牌| 国产精品国产av在线观看| 亚洲,一卡二卡三卡| 亚洲欧美精品自产自拍| 久久久精品区二区三区| 十分钟在线观看高清视频www| 热99久久久久精品小说推荐| 精品高清国产在线一区| 电影成人av| 久久久久久久国产电影| 免费久久久久久久精品成人欧美视频| 在线天堂中文资源库| 最近手机中文字幕大全| 日韩av不卡免费在线播放| 18禁观看日本| 久久久精品94久久精品| 视频区欧美日本亚洲| 国产精品久久久久久精品电影小说| 成人黄色视频免费在线看| 天天影视国产精品| 精品少妇久久久久久888优播| 欧美激情高清一区二区三区| 韩国高清视频一区二区三区| 国产成人91sexporn| 成人午夜精彩视频在线观看| 国产免费视频播放在线视频| 老鸭窝网址在线观看| 国产一级毛片在线| 婷婷丁香在线五月| 在线天堂中文资源库| 久久久久网色| 最黄视频免费看| 亚洲国产看品久久| av国产精品久久久久影院| 国产福利在线免费观看视频| 亚洲国产成人一精品久久久| 啦啦啦在线观看免费高清www| 国产欧美日韩精品亚洲av| 亚洲精品国产av成人精品| 国产精品偷伦视频观看了| 国产在线一区二区三区精| 精品一区在线观看国产| 天天添夜夜摸| 国产视频一区二区在线看| 菩萨蛮人人尽说江南好唐韦庄| 午夜免费男女啪啪视频观看| 丰满少妇做爰视频| 亚洲五月婷婷丁香| 国产成人系列免费观看| xxxhd国产人妻xxx| 欧美精品一区二区大全| 伊人久久大香线蕉亚洲五| 久久久精品94久久精品| 成在线人永久免费视频| 一区二区三区激情视频| 亚洲成国产人片在线观看| 亚洲久久久国产精品| 老司机影院成人| 欧美日韩福利视频一区二区| 午夜福利乱码中文字幕| 亚洲av片天天在线观看| 亚洲人成电影观看| 午夜影院在线不卡| 国产av国产精品国产| 大型av网站在线播放| 欧美+亚洲+日韩+国产| 久久ye,这里只有精品| 国产男女超爽视频在线观看| 在线观看www视频免费| 色综合欧美亚洲国产小说| 国产一区二区激情短视频 | 亚洲男人天堂网一区| 热99国产精品久久久久久7| 亚洲天堂av无毛| h视频一区二区三区| av国产久精品久网站免费入址| 丝袜人妻中文字幕| 搡老岳熟女国产| 少妇猛男粗大的猛烈进出视频| 亚洲一区二区三区欧美精品| av在线app专区| xxxhd国产人妻xxx| 一级片免费观看大全| 国产亚洲精品第一综合不卡| 脱女人内裤的视频| 日韩av不卡免费在线播放| 精品亚洲成国产av| 一区二区三区四区激情视频| 久久久亚洲精品成人影院| 午夜福利视频在线观看免费| 亚洲,一卡二卡三卡| 亚洲精品自拍成人| 在线观看一区二区三区激情| 欧美 亚洲 国产 日韩一| 观看av在线不卡| 赤兔流量卡办理| 国语对白做爰xxxⅹ性视频网站| 观看av在线不卡| 亚洲人成网站在线观看播放| 人妻人人澡人人爽人人| 后天国语完整版免费观看| tube8黄色片| av国产精品久久久久影院| 免费看十八禁软件| 亚洲第一av免费看|