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1.
利用傅里叶变换红外(FTIR)光谱仪联合衰减全反射(ATR)探头的中红外光导纤维对46名健康志愿者及113名乳腺肿物患者的体表皮肤进行无创红外光谱测定, 并从分子水平比较、分析了正常乳腺和有肿物乳腺体表皮肤的红外光谱特征. 结果表明, 健康志愿者乳房皮肤8个FTIR光谱测定部位的图谱趋于一致; 正常乳腺体表与有肿瘤乳腺体表的吸收峰差异明显, 而1080 cm-1处核酸相关吸收峰的变化对鉴别肿瘤的良、 恶性有重要意义.  相似文献   

2.
女性乳腺肿瘤的傅里叶变换红外光谱鉴别方法的探索   总被引:10,自引:0,他引:10  
通过75例女性良,恶性乳腺肿瘤及正常乳腺组织的傅里叶变换红外光谱(FTIR)对比研究发现,它们之间存在着明显而规律的光谱差异,这反 映了组织中蛋白质,核酸和脂类等生物分子在不同性质的乳腺肿瘤中的构型与构像及以及相对含量上的差别,研究表明,FTIR可从分子水平上揭示肿瘤组织的特性,能对良,恶性乳腺肿瘤的鉴别提供丰富而可靠的结构信息,极有可能发展成为一种肿瘤鉴别方法.  相似文献   

3.
应用傅里叶变换红外光谱(FTIR)测定了184例胃镜样品,总结不同病变类型组织的光谱特征,并与病理结果进行比较.实验结果表明,由于不同类型病变组织会在其分子组成和结构上发生相应改变,浅表性胃炎、萎缩性胃炎和胃癌组织具有不同的FTIR光谱,可据此进行胃镜样品疾病类型和病变程度的判别.研究结果表明,FTIR技术有望发展成为一种用于胃镜样品无创、快速、准确的在体临床诊断的新方法.  相似文献   

4.
采用傅里叶变换红外光谱直接测定法测定了延胡索及其伪品齿瓣元胡、东北延胡索、土元胡、新疆延胡索及夏天无的傅里叶变换红外光谱,采用主成分析法比较了正伪品之间的差异程度.结果表明基于傅里叶变换红外光谱的主成分分析在反映同属不同种植物化学组成差异程度上具有应用价值.  相似文献   

5.
采用傅里叶变换衰减全反射中红外光谱法检测了19例液氮冻存的脑胶质瘤离体组织样品(星形细胞瘤10例, 少枝-星形细胞瘤9例), 对得到的红外光谱进行分析发现, 恶性程度不同的星形细胞瘤组织的红外光谱存在差异, 并且不同类型的脑胶质瘤组织的红外光谱也表现出较为明显的区别, 因此可以根据各个特征吸收峰的峰位、 峰形及谱峰强度等信息来区分脑胶质瘤, 并初步鉴别脑胶质瘤的性质. 研究结果表明, 通过某些特征吸收峰峰位的变化来鉴别星形细胞瘤和少枝-星形细胞瘤与病理诊断结果的符合率约为80%, 说明傅里叶变换衰减全反射中红外光谱法有望发展成为一种对样品无损伤、 快速的脑肿瘤诊断新方法.  相似文献   

6.
自组装金电极的电化学测试及其FTIR和AFM分析   总被引:3,自引:0,他引:3  
利用交流阻抗谱测试了自组装免疫电极的抗原响应特性,对生物电极解离过程的机理进行了研究,用傅里叶变换红外反射光谱(FTIR)和原子力显微镜(AFM)对电化学实验过程进行了直观观测和定量分析。  相似文献   

7.
王乃岩  许国旺 《分析化学》1995,23(11):1329-1332
本文介绍了大气毒物傅里叶变换红外光谱自动差减定量软件,介绍了方法的原理和软件的结构与功能。该技术能够进行数据库的实时咨询,差减谱位的智能搜索和光谱自动差减定量,实现了大气毒物自动定量分析。运用于实际样品分析,快速准确,优于其它的傅里叶变换红外光谱定量技术。  相似文献   

8.
天然水体底质中腐植酸的光谱表征   总被引:3,自引:0,他引:3  
分别用紫外-可见光谱、傅立叶变换红外光谱(FTIR)、三维荧光光谱和荧光等高线谱对提取的腐植酸和商品腐植酸进行了表征,并将分析结果与Aldrich和上海试剂二厂生产的腐植酸进行了比较。结果表明:3种底质腐植酸之间以及同商品腐植酸的紫外-可见光谱、傅立叶变换红外光谱(FTIR)相似,含有相同类型的官能团。对不同腐植酸的三维荧光光谱和荧光等高线谱的分析表明其在结构上存在一定的差异;腐植酸有较明显的荧光光谱特性,可以尝试使用三维荧光光谱技术来揭示其在结构上的差异。  相似文献   

9.
由于傅里叶变换谱学有许多突出优点,它引起了现代化学家的很大注意。现代谱学中的傅里叶变换核磁共振(FT-NMR),傅里叶变换红外光谱(FT-IR),傅里叶变换质谱(FT-MS)等技术国内外已有许多文献介绍。最近电化学也出现了快速傅里叶变换电化学弛豫测定法(FFT-ERM),它对于研究电化学动  相似文献   

10.
《化学分析计量》2003,12(1):10-10
傅里叶变换红外光谱联用技术 气相色谱(GC)与液相色谱(LC)是分离复杂混合物的有效方法,但仅靠保留指数定性分析未知物或未知组分始终存在着许多困难。而傅里叶变换红外光谱(FTIR)作为重要的结构测定手段,能提供许多色谱难以得到的结构信息,但它要求所分析的样品尽可能简单、纯净,而不能是复杂的混合物。因此,将色谱技术的优良分离能力与红外光谱技术独特的结构鉴别能力相结合,即两种方法的联用就可以达到取长补短的效果,无疑是一种具有很高实用价值的分离鉴别手段。例如GC/FTIR联用技  相似文献   

11.
非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。  相似文献   

12.
翟宗玺  刘树深  夏树屏 《化学学报》1990,48(10):946-950
用氧化镁氯化镁水溶液制备了8水合氯氧化镁[nMg(OH)2·MgCl2·8H2O], 并测定了其在盐酸中的溶解热, 实验结果表明, 氯氧化镁溶解热与n值呈线性关系, 根据溶解热求出5Mg(OH)2·MgCl2·8H2O和3Mg(OH)2·MgCl2·8H2O的生成热分别为-7727.1和5888.1kJ·mol^1^-。  相似文献   

13.
The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.  相似文献   

14.
Two vanilloids, (5E)-8-(4-hydroxy-3-methoxyphenyl)oct-5-en-4-one (1) and 4-[3-hydroxydecyl]-2-methoxyphenol (2), isolated from the dried seeds of Grains of Paradise (Aframomum melegueta), were synthesized; the latter compound was made as the S-enantiomer and the material derived from the seeds was found to be a 1:1.7 mixture of the R and S isomers. The synthetic route used should allow the preparation of analogs having extended alkyl chains and consequently different lipophilicity, and 3, a homolog of 2, was also prepared.  相似文献   

15.
针对恶臭测试的环境影响问题,提出了解决的实例方案,并对方案的要点及优缺点进行讨论,此方案在实际操作中具有较好的效果。  相似文献   

16.
Cotton cellulose was swollen in a sodium hydroxide solution and carboxymethylated by a two-bath method for different periods of time for each process. The kinetics of acid hydrolysis and the crystallinity of the swollen and carboxymethylated samples were measured. The proportion of broken bonds, rate constants for hydrolysis, and permeability of cellulose to hydrolyzing agents were calculated. The susceptibility of glycosidic linkages to acid hydrolysis was improved by carboxymethylation more than by swelling in alkali. The increased accessibility of carboxymethylcellulose to acid was regarded as a consequence of increased intra-and intercrystalline swelling and of the glycosidic bonds' weakness caused by the electron-attracting carboxymethyl group on the C-6 position.  相似文献   

17.
袁丽秋 《化学教育》2006,27(5):8-10
面对日益枯竭的能源危机,氢能是一种洁净、最有前景的替代能源。目前在各种制氢的方法中光催化分解水制氢的研究最多,光解水过程中催化剂最关键,本文对利用太阳能光解水的途径、提高光催化反应效率以及光催化剂的开发研究进行了综述。  相似文献   

18.
Main hydration products of two cement pastes, i.e. CSH-gel, portlandite (P) (and specific surface S) were studied by static heating, and by SEM, TEM and XRD, as a function of cement strength (C-33 and C-43) hydration time (th) and subsequent hydration in water vapour.Total change in mass on hydration and air drying, Mo, increased with strength of cement paste and with hydration time. Content of water escaping at 110 to 220°C, defined as water bound with low energy, mainly interlayer and hydrate water, was independent on cement strength but its content increased with (th). Content of chemically bound (zeolitic) water in CSH-gel, escaping at 220-400°C, was slightly dependent on strength and increased with (th). It was possibly derived from the dehydroxylation of CSH-gel and AFm phase. Portlandite water, escaping at 400-500°C, was independent on cement strength and was higher on longer hydration. Large P crystals were formed in the weaker cement paste C-33. Smaller crystals were formed in C-43 but they increased with (th). Carbonate formated on contact with air (calcite, vaterite and aragonite), decomposed in cement at 600-700oC. It was high in pastes C-33(1 month) and C-43(1 month), i.e. 5.7 and 3.3%, respectively; it was less than 1% after 6 hydration months (low sensitivity to carbonation) in agreement with the XRD study showing carbonates in the air dry paste (1month), and its absence on prolonged hydration (6 months) and on acetone treatment. Water vapour treatment of (6 months) pastes or wetting-drying increased this sensitivity.Nanosized P-crystals, detected by TEM, could contribute to the cement strength; carbonate was observed on the rims of gel clusters.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   

19.
黄酮化合物的合成研究进展   总被引:2,自引:0,他引:2  
黄酮化合物是一类具有多种生物活性的天然产物,其经典的合成方法主要为查耳酮路线和β-丙二酮路线.近年来出现了许多新技术、新方法.本文介绍了2'-羟基查尔酮的氧化关环法、黄烷酮氧化法、改进的Baker-Venkataraman法及其他合成黄酮化合物的方法.  相似文献   

20.
The aim of the presented work was the investigation of thermal oxidation of ilmenite in static air atmosphere. The investigations were carried out by use of a derivatograph (MOM, Hungary). The changes of crystallographic structure of investigated samples were identified by X-ray diffractometry on Philips PW-1710 diffractometer. In temperature above 500°C appears structure of hematite Fe2O3. On the basis of the thermogravimetric measurements, the contracting area and contracting volume models were found as the best fitting experimental data. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

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