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1.
胃癌组织与正常组织样品FTIR研究   总被引:7,自引:1,他引:6  
用傅里叶变换红外光谱仪研究胃癌组织及相应正常组织的红外光谱。结果表明癌组织样品与正常组织样品的红外光谱在峰形、峰强度、峰频率等方面均存在明显差异。讨论了磷酸二酯基团(PO2^-)的对称和反对称伸缩振动;CH3、CH2基团的伸缩及弯曲振动;C-O基团伸缩振动峰的变化。并从蛋白质、核酸氢键的角度以及膜脂碳氢链排列及构象变化角度分析了发生变化的原因。磷酸二酯基团(PO2^-)的对称伸缩振动vs,PO2^-呈现有规律性变化,即癌化后由平均1080.92cm^-1向高波数方向位移到平均1085.93cm^-1处,反对称伸缩振动vas,PO2^-由平均位于1239.64cm^-1位移到平均位于1238.73cm^-1处,表面核酸骨架上磷酸二酯基团中的氧原子形成氢键的程度加强了。另外膜脂分子中的CH2弯曲振动δCH2也呈有规律地向高波数方向移动,癌化后由平均位于1455.23cm^-1位移到1457.37cm^-1处,表面了膜脂双分子层结构中磷脂分子CH2链无序程度加大了。细胞蛋白的C-O伸缩振动谱带VC-0由平均位于1166.08cm^-1位移到平均位于1166.58cm^-1,表明癌化后细胞蛋白的C-O基团氢键的程度下降的。  相似文献   

2.
用BaO等分子取代BaF_2的方法研究了氧化物杂质对62ZrF_4·8LaE3·32BaF_2(mol%)玻璃物理性质的影响.结果表明,杂质氧化物的存在使玻璃在6μm以后的红外透过率下降,在1350cm~(-1)附近产生附加吸收峰,使并玻璃的转变温度、析晶开始温度和粘度升高.杂质氧化物在氟锆酸盐玻璃中引起的附加吸收是由F—Zr—O键在680cm~(-1)处振动的多声子过程所引起.  相似文献   

3.
采用水热合成法合成了一种结构新颖的多硼钒氧簇化合物(H2dap)6H[V12B16O54(OH)4]·12H2O(dap=1,2-diaminopropane),对化合物1进行了单晶X射线衍射,结果表明化合物1属于单斜晶系,C2/c空间群,晶胞参数a=19.027(4),b=16.142(3),c=26.679(5),α=90°,β=101.06(3)°,γ=90°,V=8 042(3)nm3,Z=4,Dc=1.962g·cm-3,μ=1.456mm-1,F(000)=4 776,7 635个可观察独立衍射点射点[I2σ(I)],最后结构精修到偏离因子R1=0.0626,wR2=0.192 7,S=1.003。该化合物的结构主要由V12B16簇单元和作为抗衡离子的1,2-丙二胺组成,且簇单元之间通过强氢键N—H…O和弱氢键C—H…O的作用连接成了二维的层状结构,层与层之间也是通过氢键的作用连接成了三维的超分子结构。此外,对化合物1进行了红外光谱、磁微扰下的二维红外相关光谱、热微扰下的二维红外相关光谱以及紫外-可见固体漫反射光谱分析的表征,探讨了化合物1的结构与谱学性质的关系。红外光谱表明νas(V—Oμ)反对称伸缩振动吸收峰和νs(V—Oμ)对称伸缩振动吸收峰分别出现在775和683cm-1,而BO3中的ν(B—O)键的振动吸收峰以及BO4四面体中的δ(B—O)的振动吸收峰分别出现在1 350和1 050cm-1,磁微扰的二维红外相关光谱表明B—O和V—O—V的伸缩振动对于磁场的变化具有敏感的响应峰,热微扰的二维红外相关光谱表明B—OH,B—O和V—O—V的伸缩振动时热微扰具有敏感的响应峰。  相似文献   

4.
我们合成有机锗化合物的重要中间体 4-三氯锗基 - 4-甲基 - 2 -戊酮 ( A)、3-三氯锗基 -3,5,5-三甲基环己酮 ( B)、2 -三氯锗基 - 2 -苯基乙基苯基酮 ( C)、2 -三苯基锗基乙基苯基酮 ( D) ,测量了他们的 Raman和 IR光谱并进行了讨论。在化合物 A- D的 Raman和 IR光谱 ,苯环中的 C- H伸缩振动 ,饱和 C- H伸缩振动 ,饱和 Ge- C伸缩振动等特征数据基本一致。C=O伸缩振动在 Raman和 IR光谱中位置基本一致 ,但在红外光谱中均为强吸收带 ,而在 Raman光谱中的峰强度差别则非常大 ,化合物 A、D的峰非常弱 ,而 C的峰则很强 ,化合物 A- C的 Ge- Cl振动均在 390 cm- 1附近出现强峰。  相似文献   

5.
本文对吸附Cu2 前后梧桐树叶的红外光谱进行了分析比较.梧桐树叶的红外吸收光谱图主要由碳水化合物如木质素、纤维素等吸收带组成.1735cm-1和1615cm-1处的吸收峰是由C=O的伸缩振动引起的;1515cm-1的吸收峰是苯环的骨架振动峰,1243cm-1处是苯羟基中C-O的伸缩振动峰.1447cm-1处的吸收峰为CH3和CH2的不对称弯曲振动峰,1370cm-1处是甲基的弯曲振动峰.吸附Cu2 后,羧基的羰基峰(1735cm-1附近)向低波数移动1-2cm-1,酮羰基峰(1616cm-1附近)向高波数移动2-8cm-1;天然树叶1242cm-1处的吸收峰红移至1238cm-1处.红外光谱比较分析的结果表明吸附Cu2 后树叶的结构仍保持完整.  相似文献   

6.
酯化前后酵母菌的红外光谱比较   总被引:10,自引:2,他引:8  
对啤酒酵母酯化前后的红外光谱进行了分析。啤酒酵母的红外光谱图主要由蛋白质的吸收带、碳水化合物的吸收带组成。1 652 cm-1处的吸收峰为酰胺Ⅰ带,是CO的伸缩振动,1 542 cm-1的吸收峰是酰胺Ⅱ带,振sup>振动和N—H的弯曲振动引起的。1 454 cm-1处的吸收峰为CH3和CH2的弯曲振动峰;1 160 cm-1处出现的峰可能为细胞壁的主要成分——碳水化合物中C—O的伸缩振动峰;1 080 cm-1处的吸收峰是由啤酒酵母中的RNA,DNA或细胞壁中存在的碳水化合物或醇中的C—O伸缩振动引起的。用甲醇酯化后在1 744和1 454 cm-1处的吸收峰强度增加,说明酵母菌细胞表面的羧基发生了酯化反应。酯化后细胞的主要成分和结构保持完整。  相似文献   

7.
五氯苯酚在赤铁矿表面吸附的红外光谱研究   总被引:2,自引:0,他引:2  
由静态实验得到了五氯苯酚在赤铁矿表面吸附的pH等温线,最大吸附量发生在pH值6.0处,赤铁矿等电点pH值8.5处的吸附量为最大吸附量的31%。通过FTIR分析了赤铁矿吸附前后的变化,研究了吸附时五氯苯酚、 赤铁矿存在形态和比例,结果表明: (1)α-Fe2O3 565 cm-1处特征峰吸附前后未发生改变,吸附发生在赤铁矿表面。(2)pH 6.0时,α-Fe2O3表面OH与水形成的氢键产生的伸缩振动峰3 438 cm-1位移到了3 417 cm-1,1 643 cm-1表面的H—O—H+的弯曲振动峰由于络合反应发生明显的减弱,1 050~1 100 cm-1处的Fe—OH键峰位移到了950 cm-1且强度增加。五氯苯酚中的1 215 cm-1的C—O键伸缩振动峰位移到1 122 cm-1,两者之间作用以静电吸附为主。(3)pH 8.5时,α-Fe2O3表面OH与水形成的氢键产生的伸缩振动峰3 438 cm-1位移到了3 428 cm-1,1 643 cm-1处弯曲振动峰由于氢键反应发生明显的减弱,1 050~1 100 cm-1处的H—O—H+的弯曲振动峰位移到了947 cm-1且强度明显增加,两者之间主要是氢键作用。  相似文献   

8.
随着近几年文玩市场的兴起,"绿龙晶"成为人们喜爱的一类新兴的宝玉石品种。目前对于"绿龙晶"的主要矿物组成的认识仍存分歧。采用常规宝石学仪器测试、电子探针、红外吸收光谱和X射线粉晶衍射测试方法对产自俄罗斯的"绿龙晶"玉的基本性质、化学成分、红外吸收光谱及矿物组成特征等进行了较为详细的研究分析。结果显示:俄罗斯"绿龙晶"玉主要为深绿至灰绿色,表面具有特殊的放射状花纹及典型的丝绢光泽,折射率约为1.57,密度为2.61g·cm-3。"绿龙晶"中SiO2的含量为36.177%~36.651%,MgO含量为36.439%~36.730%,Al2O3含量为11.961%~12.318%,FeO含量为2.304%~2.853%,具富镁贫铁特点。样品中Al/(Al+Mg+Fe)为0.185 3~0.215 9,推测其为镁铁质岩蚀变成因。样品中的Si=3.10~3.40,Fe~(2+)/R~(2+)=0~0.024 8,属叶绿泥石类型。"绿龙晶"的红外吸收光谱为特征的绿泥石振动谱峰,高频区3 673cm~(-1)附近的吸收峰为OH伸缩振动所致,1 400cm~(-1)附近吸收峰属OH弯曲频率,1 000cm~(-1)附近的三个吸收峰由Si—O伸缩振动致,400~600cm~(-1)之间的吸收谱带属于Si—O弯曲振动。其中中频区1 000cm~(-1)附近分裂的三个吸收峰1 051,1 006和968cm~(-1)可作为鉴定其为叶绿泥石的关键证据。X射线粉晶衍射分析结果与化学成分及红外吸收光谱分析结果一致,显示"绿龙晶"中的主要组成矿物为叶绿泥石,非斜绿泥石。  相似文献   

9.
对天然麦秸秆(NWS)、柠檬酸改性麦秸秆(CWS)、乙二胺改性麦秸秆(EWS)的红外光谱进行了比较分析.NWS的红外吸收光谱主要由碳水化合物如木质素、纤维素等吸收带组成.NWS表面的羟基吸收峰出现在3405.16cm-1、2916.81cm-1处的吸收峰来自亚甲基中C—H的伸缩振动.1736.02cm-1和1602.21cm-1处的吸收峰是由C=O的伸缩振动引起的;苯环的骨架伸缩振动峰出现在1511.33cm-1;1425.47cm-1处的吸收峰是来自羧基的C—O伸缩振动,1376.19cm-1处为CH2的弯曲振动峰.与NWS的红外光谱图相比,CWS的主要变化为1738.13cm-1和1592.06cm-1处C=O吸收峰强度显著增加;EWS的主要变化为3405.16cm-1处的吸收峰蓝移至3417.43cm-1,且强度增加,1736.02cm-1处的吸收峰消失,CH2的C—H伸缩振动峰(2903.49cm-1)和弯曲振动峰(1382.91cm-1)强度显著增加,结果说明改性后分别引入了羧基和胺基.  相似文献   

10.
利用常规宝石学仪器、电子探针、傅里叶变换红外光谱仪、激光拉曼光谱仪、紫外-可见分光光度计和三维荧光光谱仪等,对马达加斯加黄色方柱石的宝石学性质及谱学特征进行了研究分析。马达加斯加方柱石的宝石学特征与方柱石理论值基本一致;方柱石样品颜色均匀,具有玻璃光泽,原石晶型较为完好且表面普遍可见纵纹及褐红色杂质,部分样品表面可见晕彩效应,样品内部可见多种包裹体,如黑云母、无色晶体包裹体等。红外光谱分析结果表明,样品在指纹区均显示1 039,1 105和1 196 cm-1处 Si(Al)—O伸缩振动吸收峰;752 cm-1处Si—Si(Al)伸缩振动吸收峰;551,687和624 cm-1处O—Si (Al)—O 弯曲振动吸收峰;459 cm-1处Si—O—Si的弯曲振动与Na(Ca)—O伸缩振动的耦合吸收峰;416 cm-1处Si—O—Si弯曲振动吸收峰。红外光谱官能团区的诊断性鉴定依据为:3 530和3 592 cm-1处O—H振动引起的吸收峰;2 499,2 629和2 964 cm-1处CO2-3振动产生的吸收峰。拉曼光谱分析结果表明,桥氧弯曲振动产生459和538 cm-1两处吸收峰;Al—O振动导致775 cm-1吸收峰;硅氧四面体Q4结构单元振动产生1 114 cm-1吸收峰。紫外-可见光吸收光谱可知,马达加斯加方柱石为过渡金属元素致色,铁离子的存在导致了379和420 nm两处吸收峰,且420 nm吸收峰的强弱影响着方柱石的颜色深浅。致色原因为占据了晶体结构中四面体位置的Fe2+与Fe3+之间电荷转移,从而产生黄色。三维荧光光谱分析显示,方柱石具有较为一致的发光行为,均可见一强一弱两个荧光峰,多集中在302 nm(λex)/343 nm(λem)附近。电子探针成分分析结果表明样品属于方柱石族系列中的针柱石,Ma值范围为66%~69%, 平均Ma值为68.1%,且随着Ma值的增高,双折射率随着变小。谱学测试作为无损测试技术,适用于鉴定宝石品种。对鉴定马达加斯加方柱石具有重要的意义,同时为产地溯源、区分优化处理品种提供数据支持。  相似文献   

11.
The optical and acoustic properties of tellurite glasses in the system TeO2/ZrO2/WO3 have been investigated. The refractive index at different wavelengths and the optical spectra of the glasses have been measured. From the refractive index and absorption edge studies for prepared glasses, the optical parameter viz; optical band gap (Eopt), Urbach energy, (ΔE), dispersion energy, Ed, and the average oscillator energy, E0, have been calculated. Sound velocities were measured by pulse echo technique. From these velocities and densities values, various elastic moduli were calculated. The variations in the refractive index, optical energy gap and elastic moduli with WO3 content have been discussed in terms of the glass structure. Quantitatively, we used the bond compression model for analyzing the room temperature elastic moduli data. By calculating the number of bonds per unit volume, the average stretching force constant, and the average ring size we can extract valuable information about the structure of the present glasses.  相似文献   

12.
Infrared spectra of the ethanol–water and methanol–water mixtures in the mole fraction range of 0.1 to 0.9 were recorded in the attenuated reflection (ATR) mode. Traditionally, the hydrogen bonding of water with other molecules has been studied by investigation of the OH stretching band frequencies and intensities of water. However, in the case of alcohol–water mixtures, this procedure presents a problem due to the complete overlap of the hydroxyl absorptions from the alcohol and water. In the present study, we have adopted an alternative approach of understanding the ethanol–water and methanol–water hydrogen bonds through the analysis of the C-O stretching band. The intrinsic high intensity of the C-O band and nearly complete absence of its overlap with the water bands make it a good candidate for the study of hydrogen bonding interactions in alcohol–water mixtures. The integrated areas of the C-O stretching band versus mole fractions were plotted for both mixtures. In the case of methanol–water mixtures, the C-O stretching band area plot was linear, whereas such plot for the ethanol–water mixtures had two distinct slopes that switched at the 0.5 mole fraction. The C-O band plot areas were used to explain the molecular associations in the mixtures studied.  相似文献   

13.
An analysis of the complex absorption profile of hydrargillite in the region of stretching vibrations of the OH bond has been performed with the use of the method of direct fitting of the second-derivative curve. The observed profile is shown to contain an intense broad absorption band masked by eight mutually overlapping relatively narrow bands of structural OH groups of aluminum trihydroxide. The revealed broad absorption band is apparently due to the stretching vibrations of water molecules localized in the trihydroxide structure and the stretching vibrations of structural OH groups interacting with them via the hydrogen bond. An estimation of the basic spectral characteristics of the absorption bands forming the complex profile has been performed. Translated from Zhurnal Prikladnoi Spekroskopii, Vol. 67, No. 3, pp. 306–311, May–June, 2000.  相似文献   

14.
Using a physical and chemical dehydration technique and a high-pressure, ultradry O2 atmosphere in a semiclosed steel-chamber furnace, we fabricated a group of fluorotellurite glasses with a composition of (90-x)TeO2-xZnF2-10Na2O (mol.%, x=0-30). For x=30, no OH absorption was observed in the range of 0.38-6.1?μm. This is the first report of a water-free mid-IR fluorotellurite glass, to our knowledge, offering the common advantages of a robust oxide glass and an IR-transparent fluoride one. Besides optimized linear transmittance and absorption, the nonlinear refractive indices and Raman gain coefficients are reduced. These results are discussed in the context of mid-IR high-power laser generation and transmission.  相似文献   

15.
制备了一种新型的氧卤碲酸盐玻璃:TeO2-Nb2O5-YF3,给出并研究了TeO2-Nb2O5-YF3三元系统的玻璃形成范围。测试了玻璃的密度、折射率、差热(DTA)、拉曼光谱、红外透射光谱以及紫外吸收光谱,通过光谱分析研究了组分含量的变化对玻璃结构及红外透射特性的影响。实验结果表明,TeO2-Nb2O5-YF3玻璃系统具有优良的成玻璃性能和热稳定性等特性,而且在2.8~3.3μm区域内无明显的[OH]基团吸收,在中红外3~5μm区域具有优良透射性能,因此在中红外透射方面具有潜在应用价值。  相似文献   

16.
The dual channel thermal imager, operating in the 3–5 and 7.5–10.6 μm wavelength bands, is one of the latest achievements in instrumentation for target recognition and acquisition. While the 3–5 μm band is utilised for detecting hot objects such as engine exhausts of vehicles and fighter planes, the 7.5–10.6 μm band is employed for human bodies and objects at ambient temperatures. Many substrates are available which transmit in both these wavelength bands and their transmission can be enhanced by providing a suitable antireflection coating. In this paper, a broad band antireflection coating on germanium substrate is reported. The design approach involves achieving a continuously varying refractive index from that of the incident medium to the substrate. The continuously varying refractive index profile may be generated by using a sequence of thin layers of high and low refractive index materials. In this design a continuous refractive index profile is approximated by using a 13-layer stack of thorium fluoride and germanium as low and high index coating materials respectively. This coating conforms to environmental stability standards and shows an average transmission of 91% in 3–5 μm band and 94.5% in 7.5–10.6 μm band with a peak of 97% at 9 μm on 10 mm thick germanium substrate. Polycrystalline germanium has 2.5% absorption for a 10 mm thick substrate.  相似文献   

17.
孙杜娟  胡以华*  顾有林  王勇  李乐 《物理学报》2013,62(9):94218-094218
选择枯草芽孢杆菌、黑曲霉孢子和黑曲霉菌丝体等3种典型微生物制备生物样品, 采用显微红外光谱仪对3种微生物样品在2.5—15 μm波段的红外反射光谱进行测定, 基于Kramers-Kronig (K-K)关系计算得到了微生物样品在6—14 μm波段的复折射率. 以水、蛋白质和核酸的红外吸收特性为基础,根据微生物样品的 红外吸收谱线计算了微生物样品含水量. 在3种微生物远红外波段复折射率和含水量的实测数据基础上, 构建了生物颗粒在6—14 μm远红外波段的复折射率模型, 分析了模型的可靠性. 模型的构建对发展生物样品的快速分析、鉴定方法, 进而推动生物气溶胶探测、识别技术进步具有重要意义. 关键词: 光学参数 微生物复折射率模型 远红外波段  相似文献   

18.
In the troposphere,the destruction of ozone and the formation of new particles are closely related to the iodine content,which mainly comes from iodide(I~-) and iodate(IO_3~-) in the seawater.Therefore,understanding the interactions between I~-,IO_3~-and water molecules plays a certain role in alleviating the destruction of the ozone layer.Raman spectroscopy is commonly used to obtain the information of the interaction between I~-,IO_3~-and water molecules quickly and accurately.Herein,the effect of I~-and IO_3~-on the change in Raman band characteristics of water is investigated to reflect the associated intermolecular interactions change.With the addition of the two ions,the Raman band corresponding to OH stretching vibration moves towards the high wavenumber,indicating the formation of hydration structure.The narrowing of the Raman band from OH stretching vibration under weak hydrogen bond agrees well with the hydrogen bond variation,while the abnormal broadening of the Raman band from OH stretching vibration under strong hydrogen bond indicates the formation of H-down structure.With the increase of ions concentration,the frequency shift of the Raman band from OH stretching vibration under both weak and strong hydrogen bonds becomes more apparent.Meanwhile,the frequency shift of I~-is more obvious than that of IO_3~-,which indicates that I-is more likely to form the hydration structure with water than IO_3~-.These results contribute to analyzing the different interactions between I~--water and IO_3~--water,then helping to prevent ozone depletion.  相似文献   

19.
为了分析云南楚雄新发现粘土矿中主要矿物组成,确定其主要矿物是否是凹凸棒石粘土,对其五种样品进行了红外光谱与X射线荧光光谱的测试与研究。结果发现,3 437 cm-1处的吸收带是凹凸棒石粘土中的结晶水的羟基振动引起的,3 621和3 651 cm-1处的吸收带是与凹凸棒石粘土孔道边缘的Mg, Al八面体相连的结构水的羟基的对称和不对称伸缩振动产生的;3 699 cm-1处的吸收峰是与结构内部的四面体结构和八面体之间的Mg,Al相连羟基的伸缩振动;1 633 cm-1处的吸收峰是结构水与吸收水羟基弯曲振动的吸收峰;1 010 cm-1处的吸收带是共价键Si-O-Al的Si-O键的特征峰,913 cm-1处的吸收带是二八面体的羟基(Al2OH)的变形振动的特征吸收峰。表明:粘土矿的五种样品均含有较高凹凸棒石粘土成分;三种黑色样品的中红外光谱与谱库中凹凸棒石粘土谱图比对的相似度在93%以上,三种黑色样品含凹凸棒石粘土成分很高,五种粘土矿样品的主要矿物均是分子式为Al5Si8O20(OH2)4·4H2O的凹凸棒石粘土粘土矿样品的凹凸棒粘土的。  相似文献   

20.
Simultaneous effects of an on-center hydrogenic impurity and band edge non-parabolicity on intersubband optical absorption coefficients and refractive index changes of a typical GaAs/Al x Ga 1 x As spherical quantum dot are theoretically investigated,using the Luttinger-Kohn effective mass equation.So,electronic structure and optical properties of the system are studied by means of the matrix diagonalization technique and compact density matrix approach,respectively.Finally,effects of an impurity,band edge non-parabolicity,incident light intensity and the dot size on the linear,the third-order nonlinear and the total optical absorption coefficients and refractive index changes are investigated.Our results indicate that,the magnitudes of these optical quantities increase and their peaks shift to higher energies as the influences of the impurity and the band edge non-parabolicity are considered.Moreover,incident light intensity and the dot size have considerable effects on the optical absorption coefficients and refractive index changes.  相似文献   

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