共查询到19条相似文献,搜索用时 140 毫秒
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通过三维激发波长-发射波长-荧光强度矩阵荧光光谱(3DEEMS)的荧光等高线和发射荧光谱图研究溶解态腐殖酸及其与铅离子络合的荧光特性.结果表明,腐殖酸分子中主要存在两类能够发射荧光的有机物官能团,受pH、溶液离子强度影响,其中荧光峰A所代表的有机物官能团受这两种因素影响尤为显著.腐殖酸分子与Pb2+作用结果说明,荧光峰B所代表的有机物官能团是与Pb2+络合的主要点位,且该点位对Pb2+具有较强的络合能力.荧光峰A所代表的有机物官能团与Pb2+络合较弱,受溶液离子强度影响显著. 相似文献
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采用三维荧光(EEM)光谱技术分析了膜-生物反应器(MBR)处理餐饮废水过程中的各种溶解性有机物(DOM),并对比研究不同污泥龄(SRT)条件下DOM的EEM光谱的迁移变化特性。结果表明各种DOM的荧光物质中,普遍存在以色氨酸为代表的蛋白质类物质,且溶解性膜污染中只有高、低激发波长色氨酸,表明蛋白质类物质是导致膜污染的重要因素。腐殖酸溯源又表明进水及出水DOM中的腐殖酸以微生物代谢产生的带有荧光基团的腐殖酸类为主。 相似文献
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用复合溶剂代替乙醚作溶剂,通过格氏反应由四氯化锡制得粗四丁基锡(简称TBT),四丁基锡含量≥85%,三丁基氯化锡含量≤15%,将粗TBT与四氯化锡在催化剂的作用下反应,反应完毕后,将反应物用酸洗,分相制得粗二丁基氯化锡,再减压脱水制得精二丁基氯化锡,二丁基氯化锡和氢氧化钠反应制得二丁基氧化锡,以SnCl4为原料合成二丁基氧化锡的小试收率以含锡量计为95.26%. 相似文献
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竹红菌甲素与牛血清白蛋白相互作用光谱研究 总被引:1,自引:0,他引:1
利用紫外-可见(UV—Vis)吸收光谱和荧光光谱研究在生理pH值条件下,竹红菌甲素(Hypocre-llin A,HA)与牛血清白蛋白(BSA)的相互作用。UV—Vis吸收光谱中HA的吸收峰蓝移,表明HA的存在使BSA分子中的氨基酸残基形成氢键。荧光光谱结果表明,BSA的存在对于HA的荧光发射峰具有一定的影响。双分子猝灭速率常数为1.65×10^12L·(mol·s)^-1,表明HA与BSA相互作用发生在HA与BSA分子外部的氨基酸残基之间,与BSA分子内部结构没有直接的相互作用。 相似文献
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Matthias Hayduk Steffen Riebe Kevin Rudolph Sandrina Schwarze Felix van der Vight Dr. Constantin G. Daniliuc Prof. Dr. Georg Jansen Prof. Dr. Jens Voskuhl 《Israel journal of chemistry》2018,58(8):927-931
In this communication we report the synthesis and characterisation of a novel dianionic compound with aggregation-induced emission properties. This compound was able to recognize spermine via a multivalent electrostatic interaction leading to a restriction of intramolecular rotation enhancing the fluorescence emission. This recognition was investigated in detail using UV-Vis and fluorescence spectroscopy. Furthermore the binding stoichiometry was determined via isothermal titration calorimetry. Besides that the structure of the compound was confirmed by X-ray crystallography. To proof the bivalent binding a singly negatively charged control compound was synthesized showing no specific interaction with the amines screened. Theoretical calculations were performed to get a deeper insight in the molecular structure and the electronic transitions. 相似文献
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The thermo gravimetric analysis (TGA) and differential scanning calorimetric analysis (DSC) were used to study the thermal degradation of poly(acrylic acid) PAA and poly(acrylamide) PAAm as well as the compound obtained from their interactions. The examination of the thermal curves revealed that the characteristics of the curves of the compound resulting from the cooperative interactions are different from those of the constituent polymers. The differences in the characteristics of the thermal curves were attributed to the formation of an interpolymer complex resulting from the interaction of PAA with PAAm at low pH value. These two thermal techniques were also used to investigate the thermal behavior of the compounds obtained from the interaction of PAA and (PAA‐PAAm) mixture with bone powders (BP) and hydroxyapatite (HA). It was found that the TGA, DTG, and DSC curves do not show the peak of formation and degradation of PAA anhydride which provided strong evidence for the consumption of PAA in the reaction between the polymer and BP. The interaction between PAA and the thermally treated BPs and HA was investigated. Moreover the interaction between the mixture of PAA and PAAm at different pH values and the BPs and HA was discussed. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007 相似文献
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在传统介孔二氧化硅合成的基础上,以壳聚糖的Ca2+溶液作为扩孔剂,利用层层自组装技术包裹CS(壳聚糖)/HA(透明质酸)层,制备得到了可降解的大孔二氧化硅[DMSNs@(CS/HA)],在DMSNs@(CS/HA)上负载疏水性药物锌酞菁(ZnPc),得到了负载锌酞菁的二氧化硅纳米载体[DMSNs@(CS/HA)@ZnPc]。将其应用于光动力学抗肿瘤研究。采用SEM、TEM、FTIR、XRD、UV-vis、N2吸附等温线和荧光成像技术对DMSNs@(CS/HA)和DMSNs@(CS/HA)@ZnPc进行了物相、形貌、孔径分布、结构、肿瘤光动力学治疗测试。结果表明,当DMSNs@(CS/HA)纳米载体的质量浓度为50 mg/L,Hela细胞的相对存活率高达93.2%,而负载ZnPc并在近红外光照10 min后,细胞存活率则锐减到36.2%。细胞存活率及其荧光成像实验均表明DMSNs@(CS/HA)纳米载体具有良好的生物相容性,可有效负载ZnPc,并应用于近红外照射下光动力学抗肿瘤。 相似文献
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Polymeric micelles based on hyaluronic acid and phospholipids: Design,characterization, and cytotoxicity 下载免费PDF全文
Novel amphiphilic copolymers were synthesized and characterized by 1H NMR using Hyaluronic acid (HA) as a hydrophilic part and phosphatidylethanolamine (PE) including 1,2‐dimiristoyl‐sn‐glycerol‐3‐phosphatidylethanolamine (DMPE) and 1,2‐distearoyl‐sn‐glycerol‐3‐phosphatidylethanolamine (DSPE) as a hydrophobic segment. The newly developed HA‐PE copolymers form a micelle in an aqueous media. The micellar properties, including critical micelle concentration (CMC) with pyrene as a fluorescence probe and micelle morphology, using transmission electron microscopy were assessed. It was found that the CMC values for HA‐DMPE and HA‐DSPE were 15.5 and 13.4 μg/mL, respectively. Also micelles were spherical in shape and within the size range of 162–214 nm. The solubility of cholesterol, a highly hydrophobic compound, was enhanced to 0.25 mg/mL which is much higher than it is in water (0.0001 mg/mL). In vitro cytotoxicity assay of HA‐PE copolymers showed no toxicity on human breast cancer cell line (MCF‐7). These results suggest that HA‐PE micelles could be considered as a promising carrier for delivery of hydrophobic compounds. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40944. 相似文献
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含硅羟基磷灰石生物陶瓷的湿法合成及结构特征 总被引:1,自引:1,他引:1
将硅(Si)掺入羟基磷灰石(hydroxyapatite,HA)的晶格中能有效提高HA的生物活性.用湿法合成了含硅的羟基磷灰石微粉(Si-HA).用X射线荧光光谱、X射线衍射、红外光谱(Fourier transform infrared spectroscopy,FTIR)、扫描电镜和荧光光谱等对Si-HA的晶相、结构、化学组成、形貌及其与牛血清白蛋白(Bovine serum albumin,BSA)的相互作用进行了表征和分析.结果表明:Si元素溶入HA晶格中,使HA晶胞参数和结构发生变化.随着Si含量的增加,HA中-OH和PO43-的吸收峰呈减弱趋势,证明SiO44-部分取代了PO43-.FTIR光谱和荧光光谱分析表明:Si-HA与BSA作用后的PO43-吸收峰和蛋白质内源的荧光光谱明显减弱,在Si-HA荧光光谱中出现了蛋白质的酰胺Ⅰ带和酰胺Ⅱ带吸收峰,吸收峰随Si质量分数的增加而增强.与纯HA与BSA的作用相比,Si-HA与BSA的作用更强,说明Si-HA中的Ca2 ,PO43-,SiO44-与BSA之间发生了相互溶解、吸附和键合等作用,证明Si-HA与生命物质蛋白质之间具有高的反应活性.本文详尽阐述了Si-HA的生物活性及其与BSA相互作用的机理. 相似文献