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Structure and Two-dimensional Correlation Infrared Spectroscopy Study of a New One-dimensional Chain Compound: (4,4’-Hbpy)_3[NaMo_8O_(26)](4,4’- bpy)_2(H_2O)_4 (bpy = Bipydine) 被引量:2
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作者 陈义平 张汉辉 +3 位作者 柯大梅 沈小敏 黄长沧 孙瑞卿 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第9期1033-1038,共6页
A novel compound, (4,4'-Hbpy)3[NaMo8O26](4,4'-bpy)2(H2O)4 1 (bpy=bipydine), was synthesized by the hydrothermal method. Single-crystal X-ray diffraction shows that compound 1 belongs to the monoclinic system... A novel compound, (4,4'-Hbpy)3[NaMo8O26](4,4'-bpy)2(H2O)4 1 (bpy=bipydine), was synthesized by the hydrothermal method. Single-crystal X-ray diffraction shows that compound 1 belongs to the monoclinic system, space group C2/m with a=19.1921(5), b=18.6931(6), c=9.3821(3) A° β=104.8020(11)°, V=3254.22(17)A°^3 C50H51Mo8N10NaO30, Mr=2062.52, Z=2, F(000)=2016, μ=1.591 mm^-1 and Dc=2.105 g/cm^3. The final R=0.0283 and wR=0.0912 for 3118 observed reflections (I〉20(I)). Compound 1 contains the β-[Mo8O26]^4-anion, sodium ion, 4,4'-bpy and lattice crystalline water molecules. The β-[MosO26] units link the sodium ion to form a chain structure. The infinitechains of [Na(Mo8O26)]^3- blocks are surrounded by protonized 4,4'-bpy cations, 4,4'-bpy and lattice crystalline water molecules. The 2D-IR correlation spectroscopy study indicates that the stretching vibrations of Mo=O occur more preferentially due to the thermal effect. The TGA analysis shows that compound 1 has high thermal stability. 展开更多
关键词 OCTAMOLYBDATE sodium ion two-dimensional infrared (2D-ir correlation spectroscopy
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IR study on surface chemical properties of catalytic grown carbon nanotubes and nanofibers 被引量:1
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作者 Li-hua TENG Tian-di TANG 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第5期720-726,共7页
In this study, the surface chemical properties of carbon nanotubes (CNTs) and carbon nanofibers (CNFs) grown by catalytic decomposition of methane on nickel and cobalt based catalysts were studied by DRIFT (Diffuse Re... In this study, the surface chemical properties of carbon nanotubes (CNTs) and carbon nanofibers (CNFs) grown by catalytic decomposition of methane on nickel and cobalt based catalysts were studied by DRIFT (Diffuse Reflectance Infrared Fourier Transform) and transmission Infrared (IR) spectroscopy. The results show that the surface exists not only carbon-hydrogen groups, but also carboxyl, ketene or quinone (carbonyl) oxygen-containing groups. These functional groups were formed in the process of the material growth, which result in large amount of chemical defect sites on the walls. 展开更多
关键词 Carbon nanotubes (CNTs) Carbon nanofibers (CNFs) Functional surface groups infrared ir spectroscopy
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Light-Induced Mid-Infrared Emission of Liquid Carbon Tetrachloride and Benzene
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作者 Sofya Terpugova Olga Degtyareva +1 位作者 Valery Savransky Evgeni Terpugov 《American Journal of Analytical Chemistry》 2015年第9期731-745,共15页
Light-induced infrared emission spectroscopy (LIRES) is a novel technique that permits to receive high-quality spectra in the mid-infrared region. Low-intensity visible light connected to a highly sensitive FTIR spect... Light-induced infrared emission spectroscopy (LIRES) is a novel technique that permits to receive high-quality spectra in the mid-infrared region. Low-intensity visible light connected to a highly sensitive FTIR spectrometer is more advantageous for studying any samples, including biological samples without any damage. This technique permits obtaining unique information on the molecule structure via vibrational excitation fundamental frequencies, overtones, and combination modes. It also enables a direct observation of vibrational radiation transitions in vibrationally excited molecules as well as the channels of vibration energy redistribution, which is not allowed with any other method. In this work, the LIRES is being tested as a technique for studying of vibrationally-excited molecules of carbon tetrachloride and benzene in the liquid phase. On the other hand, using transparent liquids, we had tried to understand some of the physical phenomena that can drive emission in mid-IR. The characteristics of the infrared emission of both liquid species produced by different wavelength radiation from various types of light systems (100 - watt Xe-lamp and Nd:YAG laser;lambda = 1064 nm (8 mW) and lambda = 532 nm (4 mW)) are presented. We demonstrated that the IR-signal, as well as spectral properties of carbon tetrachloride and benzene, was dependent on the wavelength and power of excitation beam. Results obtained with different light sources show that the visible light produces a nonlinear IR-emission signal in transparent liquids. We believe that the visible light is the source of the nonlinear response and is producing the vibration excitation as well as photostimulated transformations of the molecules possessing the high activity for the nonlinear response. 展开更多
关键词 FT-ir EMISSION spectroscopy LIGHT-INDUCED MID-infrared EMISSION Carbon TETRACHLORIDE BENZENE Xe-Lamp Nd:YAG Laser
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氟诺哌齐结构和性质的密度泛函理论研究
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作者 孙婷婷 王德堂 《原子与分子物理学报》 CAS 北大核心 2025年第2期41-48,共8页
氟诺哌齐是一种新型的抗阿尔茨海默病临床候选药物,目前尚处于临床试验阶段;对氟诺哌齐进行密度泛函理论研究,有助于揭示其分子的性质和功能.在B3LYP/6-311+G(d,p)基组水平上,采用密度泛函理论(DFT)的方法优化氟诺哌齐的分子结构;在相... 氟诺哌齐是一种新型的抗阿尔茨海默病临床候选药物,目前尚处于临床试验阶段;对氟诺哌齐进行密度泛函理论研究,有助于揭示其分子的性质和功能.在B3LYP/6-311+G(d,p)基组水平上,采用密度泛函理论(DFT)的方法优化氟诺哌齐的分子结构;在相同基组水平下经过谐振频率分析,证实了12种分子构象的稳定结构,并确定了优势构型为DC20-1.根据Marcus理论,对其重组能进行模拟计算,得出氟诺哌齐分子不具备运输性质.通过前线轨道(FMO)分析,发现氟诺哌齐分子具有一定的电子跃迁能力和分子内反应活性,活性反应位点为C15、O28、C23和O26.根据红外光谱、紫外-可见吸收光谱模拟计算结果,对谱图数据进行了讨论分析,研究结果可作为氟诺哌齐表征和鉴别的参考依据. 展开更多
关键词 氟诺哌齐 密度泛函(DFT) 重组能 前线轨道(FMO) 红外光谱(ir) 紫外-可见吸收光谱(UV-Vis)
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FT-IR在研究蛋白质二级结构中的应用 被引量:14
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作者 高红艳 许强 杨志怀 《宝鸡文理学院学报(自然科学版)》 CAS 2009年第3期47-53,共7页
目的研究蛋白质的二级结构。方法介绍蛋白质二级结构定量分析方法,综述FT-IR在蛋白质二级结构研究中的应用进展情况,并对其应用前景进行了展望。结果FT-IR分析技术是一种高效、快速研究蛋白质结构的现代分析技术。结论为了获得更精确的... 目的研究蛋白质的二级结构。方法介绍蛋白质二级结构定量分析方法,综述FT-IR在蛋白质二级结构研究中的应用进展情况,并对其应用前景进行了展望。结果FT-IR分析技术是一种高效、快速研究蛋白质结构的现代分析技术。结论为了获得更精确的信息,须将FT-IR技术与生物样品的处理与实验设计相结合。 展开更多
关键词 FT-ir 蛋白质二级结构 二阶导数谱 去卷积 曲线拟合
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固/液界面原位红外显微镜和步进扫描时间分辨FTIR反射光谱及其在纳米材料科学中的应用 被引量:2
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作者 孙世刚 贡辉 +4 位作者 周志有 陈声培 陈友江 司迪 李君涛 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2004年第4期431-433,共3页
结合红外显微镜和步进扫描FTIR光谱仪 ,发展了固 /液界面电化学原位显微镜红外反射光谱和步进扫描快速时间分辨FTIR反射光谱 ,并应用于纳米材料特殊性能和电化学反应动力学的研究。研制纳米结构Pt微电极 ,获得CO吸附的红外特征随纳米结... 结合红外显微镜和步进扫描FTIR光谱仪 ,发展了固 /液界面电化学原位显微镜红外反射光谱和步进扫描快速时间分辨FTIR反射光谱 ,并应用于纳米材料特殊性能和电化学反应动力学的研究。研制纳米结构Pt微电极 ,获得CO吸附的红外特征随纳米结构和纳米尺度变化的原位显微镜红外谱图。利用纳米结构Pt微电极的异常红外效应 ,显著提高电化学原位红外反射光谱的灵敏度 ,获得分辨率达 5 0 μs的步进扫描时间分辨光谱。不仅发展了固 /液界面显微镜原位红外反射光谱新方法 ,并且拓展了电化学原位红外反射光谱在纳米材料科学研究中的应用。 展开更多
关键词 纳米材料 原位红外反射光谱 异常红外效应 步进扫描 分辨率
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基于FT-IR及二维相关分析的SBS超热老化机理 被引量:5
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作者 郝增恒 李璐 +1 位作者 王民 盛兴跃 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2015年第7期119-123,共5页
通过原位动态红外光谱分析技术,发现苯乙烯-丁二烯-苯乙烯嵌段共聚物(SBS)在250℃的超热老化过程中,SBS分子中的C=C双键受到氧原子的进攻,其吸收峰随老化时间延长呈明显降低的趋势,生成羰基、羟基和醚键等一系列的氧化产物,并且老化时... 通过原位动态红外光谱分析技术,发现苯乙烯-丁二烯-苯乙烯嵌段共聚物(SBS)在250℃的超热老化过程中,SBS分子中的C=C双键受到氧原子的进攻,其吸收峰随老化时间延长呈明显降低的趋势,生成羰基、羟基和醚键等一系列的氧化产物,并且老化时间越长,SBS受老化程度越高;采用二维相关红外分析技术,进一步发现SBS在超热老化过程中,氧原子同时会进攻SBS分子链上的亚甲基,并且主要进攻SBS中的非对称亚甲基,其次进攻对称亚甲基,形成自由基;通过同步相关谱图与异步相关谱图的对比分析,发现SBS在超热老化过程中,其氧化产物羰基的变化落后于醚键的变化,而羟基的变化又落后于羰基的变化,其氧化产物的生成速率为醚键>羰基>羟基;其中羰基的存在形式主要以醛酮为主,并伴随生成少量的羧酸。 展开更多
关键词 苯乙烯-丁二烯-苯乙烯嵌段共聚物 超热老化 傅里叶变换红外光谱 二维相关红外
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溶剂分子与Nafion膜、SiO_2/Nafion复合膜的相互作用
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作者 任素贞 唐林 《电池》 CAS CSCD 北大核心 2010年第2期96-99,共4页
用溶胶-凝胶法把SiO2复合到Nafion膜的亲水相中,研究了甲醇、乙醇和水在Nafion膜及SiO2/Nafion复合膜中的溶解情况。衰减全反射(ATR)FT-IR、XRD分析结果显示:甲醇、乙醇分子容易渗透到Nafion膜的疏水区,引起渗透,导致膜的溶胀;水分子容... 用溶胶-凝胶法把SiO2复合到Nafion膜的亲水相中,研究了甲醇、乙醇和水在Nafion膜及SiO2/Nafion复合膜中的溶解情况。衰减全反射(ATR)FT-IR、XRD分析结果显示:甲醇、乙醇分子容易渗透到Nafion膜的疏水区,引起渗透,导致膜的溶胀;水分子容易与Nafion膜的亲水区相互作用,与疏水区的相互作用不明显。SiO2/Nafion复合膜在醇、水中具有与Nafion膜相似的性质,但具有阻醇作用和良好的吸水、保水功能。加入15%的SiO2有助于降低Nafion膜的渗透问题。 展开更多
关键词 NAfiON膜 SiO2/Nafion复合膜 红外光谱(FT-ir)
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Y型分子筛表面酸性的DSC和IR测定
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作者 徐瑞云 《化学世界》 CAS CSCD 北大核心 2003年第3期128-130,共3页
用 DSC法和 IR法对 Y型分子筛的表面酸性进行了研究。分别测定了预吸附 NH3 和三乙胺的 Na Y型和 HY型分子筛的 DSC曲线和摩尔解吸焓。 HY型分子筛的摩尔解吸焓大于 Na Y型分子筛。 IR图谱显示随着 Y型分子筛中硅铝比的增加 ,其骨架反... 用 DSC法和 IR法对 Y型分子筛的表面酸性进行了研究。分别测定了预吸附 NH3 和三乙胺的 Na Y型和 HY型分子筛的 DSC曲线和摩尔解吸焓。 HY型分子筛的摩尔解吸焓大于 Na Y型分子筛。 IR图谱显示随着 Y型分子筛中硅铝比的增加 ,其骨架反对称伸缩振动频率向高频移动。不同阳离子 ,其羟基振动频率吸收峰也不相同。 展开更多
关键词 Y型分子筛 DSC ir 表面酸性
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Classification and spectrum optimization method of grease based on infrared spectrum
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作者 Xin FENG Yanqiu XIA +1 位作者 Peiyuan XIE Xiaohe LI 《Friction》 SCIE EI CAS CSCD 2024年第6期1154-1164,共11页
The infrared(IR)absorption spectral data of 63 kinds of lubricating greases containing six different types of thickeners were obtained using the IR spectroscopy.The Kohonen neural network algorithm was used to identif... The infrared(IR)absorption spectral data of 63 kinds of lubricating greases containing six different types of thickeners were obtained using the IR spectroscopy.The Kohonen neural network algorithm was used to identify the type of the lubricating grease.The results show that this machine learning method can effectively eliminate the interference fringes in the IR spectrum,and complete the feature selection and dimensionality reduction of the high-dimensional spectral data.The 63 kinds of greases exhibit spatial clustering under certain IR spectrum recognition spectral bands,which are linked to characteristic peaks of lubricating greases and improve the recognition accuracy of these greases.The model achieved recognition accuracy of 100.00%,96.08%,94.87%,100.00%,and 87.50%for polyurea grease,calcium sulfonate composite grease,aluminum(Al)-based grease,bentonite grease,and lithium-based grease,respectively.Based on the different IR absorption spectrum bands produced by each kind of lubricating grease,the three-dimensional spatial distribution map of the lubricating grease drawn also verifies the accuracy of classification while recognizing the accuracy.This paper demonstrates fast recognition speed and high accuracy,proving that the Kohonen neural network algorithm has an efficient recognition ability for identifying the types of the lubricating grease. 展开更多
关键词 GREASE infrared(ir)spectroscopy layered Kohonen network species recognition spectrum band optimization
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污水厂进出水中DOM的三维荧光和FTIR光谱解析 被引量:9
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作者 王佳琴 李卫华 +4 位作者 申慧彦 黄显怀 姚亮 刘绍根 伍鲧 《环境科学与技术》 CAS CSCD 北大核心 2018年第1期71-76,共6页
采用树脂分离方法对合肥市某城市污水处理厂进出水中的溶解有机质进行分离,得到憎水性碱、憎水性酸、憎水性中性物质、亲水性碱、亲水性中性物质和亲水性酸等共6种物质。分析结果表明,憎水性组分荧光相对较强,而亲水性组分荧光则较弱。... 采用树脂分离方法对合肥市某城市污水处理厂进出水中的溶解有机质进行分离,得到憎水性碱、憎水性酸、憎水性中性物质、亲水性碱、亲水性中性物质和亲水性酸等共6种物质。分析结果表明,憎水性组分荧光相对较强,而亲水性组分荧光则较弱。采用三维荧光光谱结合各区域荧光强度积分(FRI)值分析可以得到类蛋白质、类富里酸和类胡敏酸等3种主成分的荧光积分标准体积值,出水的3种主成分荧光标准体积值比进水低,憎水性碱、亲水性碱、亲水性酸和亲水性中性物质亦呈现类似规律,说明它们在生化过程中经过微生物降解以后,荧光物质发生了降解和转化。憎水性酸中的类蛋白物质和憎水性中性物质中的3种组分相对浓度均强于进水,说明生物反应有助于生成上述2种物质.在此基础上,进一步采用傅里叶变换红外光谱定性分析进出水中各组分中官能团特征峰。结果显示,进出水中溶解有机物主要有多糖、脂类和蛋白质等物质,经过生化处理这些物质得到了显著的降解。 展开更多
关键词 树脂分离 溶解性有机质 三维荧光光谱 荧光区域积分法 傅里叶变换红外光谱
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甘草真伪品的FTIR光谱法鉴别研究 被引量:30
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作者 阿依古丽.塔西 周群 +1 位作者 董晓鸥 孙素琴 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2006年第7期1238-1241,共4页
采用傅里叶变换红外(FTIR)光谱法并结合二维相关(Two-dimensional correlation spectroscopy)分析技术分别对药用植物甘草(药材对照品)及其伪品刺果甘草进行了无损快速鉴别研究。结果表明:虽然甘草和伪品刺果甘草都是来源于同一科属,但... 采用傅里叶变换红外(FTIR)光谱法并结合二维相关(Two-dimensional correlation spectroscopy)分析技术分别对药用植物甘草(药材对照品)及其伪品刺果甘草进行了无损快速鉴别研究。结果表明:虽然甘草和伪品刺果甘草都是来源于同一科属,但两者所含化学组分的含量不同,其红外光谱图既有一定的差异,又有一定的相似。而在红外二阶导数谱图上差异较明显,在二维红外谱图的差别不但较明显而且很直观。凭借这些差异,可方便地进行真伪鉴别,同时还进一步表明了这两种甘草药材中化学组分之间的差异。该法无损,快速,准确,样品量少,为客观评价中药材的来源,真伪,优劣等提供了一种新的方法和手段。 展开更多
关键词 二维相关红外光谱法 甘草 刺果甘草 真伪鉴别
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胆石中胆红素钙的FTIR定量分析 被引量:5
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作者 宋惠芳 倪雪梅 +2 位作者 陶海燕 付贤波 周孝思 《生物化学杂志》 CSCD 1992年第3期374-380,共7页
应用付立叶变换红外光谱(FT-IR)测定胆石中胆红素钙的含量,使用KBr压片法,吸收度是由积分法表示。胆红素钙在1622.3cm^(-1),1253.1cm^(-1)等处有特征吸收峰,在FT-IR减谱分析的基础上,选定1253.1cm^(-1)为定量吸收峰,它符合Beer-Lambert... 应用付立叶变换红外光谱(FT-IR)测定胆石中胆红素钙的含量,使用KBr压片法,吸收度是由积分法表示。胆红素钙在1622.3cm^(-1),1253.1cm^(-1)等处有特征吸收峰,在FT-IR减谱分析的基础上,选定1253.1cm^(-1)为定量吸收峰,它符合Beer-Lambert’s定律(r=0.998)而且共存物干扰小。标准工作曲线是使用胆红素为标准。胆石样品中胆红素钙含量用此法测定,其结果与化学法结果相似。应用FT-IR对混合物定量分析简单、迅速、准确。 展开更多
关键词 定量分析 胆红素钙 胆石
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IR光谱研究TIR晶体结构 被引量:3
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作者 曹莲亿 郝凤岭 +1 位作者 李静怡 韩松鹤 《弹性体》 CAS 1993年第2期34-37,共4页
本文用IR光谱研究了由齐格勒系催化剂聚合的反式聚异戊二烯(TIR)的α和β型结晶体在低温下以及从室温到75℃加热时,每升高5℃的结构变化。
关键词 红外光谱 聚异戊二烯 橡胶
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红外光谱法研究PIR催化剂各组分之间的交换反应
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作者 曹莲亿 郝凤岭 +1 位作者 韩松鹤 李静怡 《烟台大学学报(自然科学与工程版)》 CAS 1995年第1期35-39,共5页
用红外光谱法研究了催化聚异戊二烯(PIR)用Nd(OPr1)3-nCl/Al(Et)3体系催化剂各组分之间的交换反应。结果发现,Nd(OPr1)Cl2与Al(Et)3之间进行的反应是卤素交换;而Nd(OPr1)2Cl... 用红外光谱法研究了催化聚异戊二烯(PIR)用Nd(OPr1)3-nCl/Al(Et)3体系催化剂各组分之间的交换反应。结果发现,Nd(OPr1)Cl2与Al(Et)3之间进行的反应是卤素交换;而Nd(OPr1)2Cl与Al(Et)3之间进行的反应是烷氧基交换。 展开更多
关键词 催化剂 红外光谱法 交换反应 聚异戊二烯
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An Investigation of Thermomechanical Behavior of Tunisian Luffa Sponges’ Fibers
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作者 Khaled Kharrati Madiha Salhi +1 位作者 Jemaa Sliman Ridha Abdeljabar 《Materials Sciences and Applications》 CAS 2022年第10期519-531,共13页
This work is realized in the context of valorizing natural and local resources, in particular, luffa plant fruit (luffa sponge). The raw fibers of the luffa sponge have a short lifetime. Hence, when they are chemicall... This work is realized in the context of valorizing natural and local resources, in particular, luffa plant fruit (luffa sponge). The raw fibers of the luffa sponge have a short lifetime. Hence, when they are chemically treated, it constitutes a solution is prepared to limit their degradation in the long term and to improve their mechanical characteristics. Therefore, this paper studies the effect of the chemical treatment on the mechanical properties of the luffa sponge’s fibers (fibers of luffa Sponge). The chemical process consists of dipping a brunch of luffa in various concentrations of sodium hydroxide (NaOH) at different time intervals and at different temperature conditions. The luffa sponge’s fibers were mechanical. Characterized before and after the treatment, mechanically (micro traction test). It has been shown that an optimum of 61% increase in mechanical properties (tensile strength) has been reached in the following conditions: treatment with 1% concentration for 90 min at 50&deg;C. 展开更多
关键词 Luffa Sponge’s fibers Chemical Treatment Thermogravimetric Analysis (TGA) X-Ray Diffraction Spectrum infrared spectroscopy (ir) Mechanical Characteristics Tensile Strength
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Preparation of Carboxymethyl Cellulose Fibers
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作者 刘树勇 闻林刚 +3 位作者 王志亮 沈端 李皆富 杨曙光 《Journal of Donghua University(English Edition)》 EI CAS 2016年第3期366-369,共4页
Carboxymethyl cellulose(CMC) fibers were produced by extruding the CMC solution into the metal salt coagulation bath and collected with a winding machine.It was found that copper chloride,ferric chloride,cerium chlori... Carboxymethyl cellulose(CMC) fibers were produced by extruding the CMC solution into the metal salt coagulation bath and collected with a winding machine.It was found that copper chloride,ferric chloride,cerium chloride,lanthanum chloride and aluminum nitrate solution could be used as coagulation bath to prepare CMC fibers,whereas the metal salt solutions,such as nickel chloride,zinc chloride,calcium chloride and magnesium chloride,could not.The fiber formation is due to the coordination between the carboxylates of CMC and metal ion.Fourier transform infrared spectroscopy(FTIR) was applied to studying the coordination mode of CMC and metal ion.The metal salt concentration,pH value and temperature of the coagulation bath affect the tenacity and elongation of the fiber.CMC fibers show good water uptake ability and can adsorb water more than 200% of its own weight.The mechanical behaviors of CMC fiber show dependence on environment humidity. 展开更多
关键词 fiBER carboxymethyl cellulose(CMC) Fourier transform infrared spectroscopy(FT-ir) COORDINATION
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Molecular interactions between anticancer drugs and iodinated contrast media: An in vitro spectroscopic study
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作者 Ryoichi Ishii Hiromu Mori +5 位作者 Kenji Matsumura Norio Hongo Hiro Kiyosue Shunro Matsumoto Takeshi Yoshimi Seiji Ujiie 《Journal of Biomedical Science and Engineering》 2012年第1期24-33,共10页
Purpose: The purpose of this study is to assess molecular interactions between several anticancer drugs and an iodinated contrast medium by Fourier transform infrared spectroscopy (FT-IR) and ultraviolet-visible spect... Purpose: The purpose of this study is to assess molecular interactions between several anticancer drugs and an iodinated contrast medium by Fourier transform infrared spectroscopy (FT-IR) and ultraviolet-visible spectroscopy (UV-Vis). Materials and Methods: Iopamidol (IPM) was used as an iodinated contrast medium, and mitomycin C (MTI), epirubicin hydrochloride (EPI), cisplatin (CDDP), 5-fluorouracil (5FU), irinotecan hydrochloride (CPT11), gemcitabine hydrochloride (dFdC), carboplatin (CBDCA), oxaliplatin (1OHP), paclitaxel hydrochloride (TAX) and docetaxel trihydrate (TXT) were used as anticancer drugs. For FT-IR, the purified IPM was mixed stoichiometrically with each anticancer drug as well as with a combination of MTI and EPI. After measuring each separated sample and the mixtures, the spectra of the mixtures were compared with the spectra of the sum of pure samples or the combination. For UV-Vis, IPM and anticancer drugs were dissolved in pure water;subsequently for the titration experiments, the mixtures were prepared by varying the molar ratio. IR absorption corresponds to stretching vibrations between atoms having covalent bonding, whereas UV-Vis spectra depend on molecular dynamics and shapes. Both UV-Vis and IR spectra change when there are molecular interactions such as aromatic ring stacking and hydrogen bonding. Result: IPM exhibited molecular interactions with MTI, EPI, CDDP, dFdC, CBDCA, 1OHP, TAX and TXT, as well as with the combination of MTI and EPI on FT-IR. However, molecular interactions were not observed on UV-Vis. Conclusion: Several anticancer drugs have molecular interactions with IPM, which could be clinically utilized for superselective intraarterial infusion chemotherapy. 展开更多
关键词 BLAST Molecular Interactions ANTICANCER Drugs Iodinated Contrast Medium FOURIER Transform infrared (FT-ir) spectroscopy Ultraviolet-Visible (UV-Vis) spectroscopy
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黑土腐殖酸对全氟辛酸的吸附特征研究
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作者 许端平 姚旺 +1 位作者 薛杨 冯肖杰 《安全与环境学报》 CAS CSCD 北大核心 2024年第6期2390-2398,共9页
研究全氟辛酸(Perfluorooctanoic Acid, PFOA)在黑土腐殖酸(Humic Acid, HA)中的吸附特征,有助于更好地理解和管理这种新兴污染物对人类健康和生态系统的潜在危险。研究以PFOA作为目标污染物,探讨其在黑土腐殖酸中的吸附动力学和等温吸... 研究全氟辛酸(Perfluorooctanoic Acid, PFOA)在黑土腐殖酸(Humic Acid, HA)中的吸附特征,有助于更好地理解和管理这种新兴污染物对人类健康和生态系统的潜在危险。研究以PFOA作为目标污染物,探讨其在黑土腐殖酸中的吸附动力学和等温吸附特征,并通过傅里叶变换红外光谱(Fourier Transform Infrared Spectroscopy, FT-IR)和核磁共振碳谱(13C Nuclear Magnetic Resonance, NMR)揭示其分子作用机理。研究结果显示:黑土腐殖酸对PFOA的吸附过程可分为3个阶段:开始为快速吸附阶段,且吸附量占总吸附量的78.8%,之后为慢速吸附阶段,直至48 h后达到吸附平衡。吸附动力学采用拉格朗日准一级动力学、准二级动力学和颗粒扩散模型对数据进行拟合,结果显示拉格朗日准二级动力学模型拟合较好(R^(2)> 0.998);吸附等温线用Henry、Freundlich和Langmuir模型对试验数据进行拟合,结果显示Freundlich和Langmuir模型拟合效果较好;吸附量随温度升高而升高,当温度为298.15 K时,其值为1.717 mg/g。此外,ΔH^(0)=30.81 kJ/mol,ΔS^(0)=168.72 J/(mol·K),ΔG^(0)在-19.49~-16.11 kJ/mol,表明腐殖酸对PFOA的吸附属于易自发过程,吸附自由能的减少是腐殖酸吸附PFOA的主要驱动力,吸附过程中的驱动力主要是氢键。通过对比吸附前后FT-IR和NMR图谱可知,腐殖酸对PFOA的吸附过程中存在离子交换和氢键作用,PFOA与腐殖酸的主要结合位点为芳香碳和脂肪碳,且PFOA会与HA发生原位化学反应并产生羧酸类物质。 展开更多
关键词 环境学 黑土腐殖酸 全氟辛酸 吸附 傅里叶变换红外光谱 核磁共振
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固体熔融法制备复合水杨酸及其结构表征
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作者 彭振刚 王艳旗 +1 位作者 李玉清 马守伟 《香料香精化妆品》 CAS 2024年第5期129-133,共5页
通过固体熔融法,利用甜菜碱和苦参碱与水杨酸组装成复合水杨酸。通过优化,最终选择w水杨酸∶w甜菜碱∶w苦参碱=1∶15∶1.7制备的复合水杨酸具有较好的水溶性,质量分数1%的复合水杨酸溶液pH值为4.7。为了研究复合水杨酸中甜菜碱和苦参碱... 通过固体熔融法,利用甜菜碱和苦参碱与水杨酸组装成复合水杨酸。通过优化,最终选择w水杨酸∶w甜菜碱∶w苦参碱=1∶15∶1.7制备的复合水杨酸具有较好的水溶性,质量分数1%的复合水杨酸溶液pH值为4.7。为了研究复合水杨酸中甜菜碱和苦参碱对水杨酸的助溶作用,利用核磁共振和红外光谱研究单体间的结合方式。分析发现甜菜碱的羧基以及苦参碱的叔胺氮和羰基通过氢键与水杨酸的羧基和羟基结合,提高了水杨酸的溶解度。 展开更多
关键词 复合水杨酸 水杨酸 甜菜碱 苦参碱 核磁共振 红外光谱
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