【作者】 万牡华；

【导师】 欧阳健明；

【作者基本信息】 暨南大学 ， 无机化学， 2009， 硕士

【摘要】 泌尿系结石是一种世界范围的常见病、多发病。但至今为止,对尿石的预防和预前诊断尚无十分理想的方法,80%以上的尿石患者病因不清。尿石症形成过程中的许多化学及物理问题还没有弄清。尿液中的纳米晶体是怎样生长聚集?随后又是怎样黏附到尿路细胞膜上并最终形成结石?正常人尿液与尿石患者尿液中纳米晶体的数量和尺寸存在什么样的区别?两类尿液中纳米晶体的生长动力学存在怎么样的差异?这些问题均不清楚。本论文采用透射电子显微镜（TEM）、扫描电子显微镜（SEM）、纳米粒度仪（Nano-ZS）、X-射线衍射分析（XRD）、傅立叶变换红外光谱（FT-IR）和紫外-可见吸收光谱（UV-vis）等方法,研究了纳米草酸钙的最佳制备条件,比较了尿液抑制剂分别与纳米COM和COD作用的差异以及在纯水体系中纳米COM和COD晶体生长机理的差异。1.采用CaCl₂和K₂Oxa为原料,NTA为络合剂,通过络合沉淀法成功的合成了直径为150-250 nm的纳米二水草酸钙（COD）。讨论了反应物初始浓度、体系pH等因素对产物粒径和形貌的影响。得出了纳米COD的最佳制备条件,讨论了放置时间、纳米CaOxa悬浮液浓度和分散介质对纳米COD稳定性的影响。初步探讨了纳米COD的形成机理。2.采用CaCl₂和K₂Oxa为原料,NTA为络合剂,通过络合沉淀法成功的合成了直径为400-600 nm的纳米一水草酸钙（COM）。比较了硫酸软骨素A和柠檬酸三钠与纳米COD和COM作用的区别。结果表明,在不同浓度的硫酸软骨素A（C₄S）和低浓度的柠檬酸三钠（Na₃cit）溶液中,纳米COD的单分散性好,在紫外-可见吸收光谱上表面了明显的量子尺寸效应;而COM则分散性差,在溶液中容易聚集,紫外吸收峰不明显。3.在纯水体系中,研究了纳米COM和COD晶体的生长差异。结果表明,到第3天COD已全部转化为COM,随着生长时间的增加,COM晶体的（（?）01）晶面的衍射峰的强度都明显增大。COM晶体在纯水体系中呈长方形和不规则的菱形的形貌,极易聚集沉淀析出;而纳米尺寸的COD则呈球形的形貌,COD转化为COM长大后主要呈规则的六边形的形貌,COD晶体在纯水体系中的生长一直为生长控制,晶体的大小随结晶时间的增加而不断增大。根据理论推导和假设的生长模型,提出了纳米COD在纯水体系中的生长机理。上述结果为研究尿结石的形成机理提供了新的启示。更多还原

【Abstract】 Urolithiasis is one of the most common urologic diseases in the world-wide area.However, up to date,there is no ideal method about the prevention of urinary stones and advanced diagnosis.The pathogeny for 80%of stone formers was not clearly understood.The mechanism for the formation of urinary stones is not yet clearly understood and a number of questions about the physical and chemical factors still remain unanswered.How do these urinary microcrystals grow,aggregate,attach to the renal tubule cell membranes,and form into urinary stones ultimately? What differentiation exists of the number and size of the nanocrystallites between the urines in healthy persons and in stone patients? What differentiation exists of dynamic process of the nanocrystallites between the urines in healthy persons and in stone patients? The questions were not yet clearly understood.In this paper,the optimal preparation condition of CaOxa nanoparticles was investigated using Transmission electron microscopy（TEM）,Scanning electron microscopy（SEM）,X-ray diffraction（XRD）,Fourier transform infrared resonance （FTIR）,Zetasizer Nano-ZS（Malvem Instruments,U.K.） and Ultraviolet-visible absorption （UV-vis）.Its interaction with the urine inhibitor was compared.And the grown mechanism of COM and COD in pure aquatic system was also discussed.The results can be summarized as follows:Firstly,COD nanoparticles with an average size of about 150-250 nm were prepared by complex precipitation method using K₂C₂O₄ and CaCl₂ as raw materials,NTA as complexing agent and a water solution as the reaction medium.The effects of initial reactant concentrations, pH in reaction system and dispersion media etc.on morphology and size of the nanoparticles were discussed.The results indicated that the prepared sample was calcium oxalate dihydrate （COD） and the morphology of the CaOxa particles was typical tetragonal bipyramid.The optimal preparation condition for nano CaOxa was as follows:the initial concentrations of three reactants were 0.1 mol/L respectively,pH=4 and T=35℃.The effect of the standing time, concentration of CaOxa suspension and the dispersion media on the stability of nano-COD was discussed.The formation mechanism of nano-COD was discussed.Secondly,COM nanoparticles with an average size of about 250-400 nm were prepared by complex precipitation method.The difference of chondroitin sulfate A and sodium citrate interaction with COM and COD were compared.The results indicated that the nano-COD has good dispersion in chondroitin sulfate A solution of different concentration and sodium citrate solution of low concentration.The quantum size effects could be seen in ultraviolet spectra. However,COM has poor dispersion and easily aggregated in solution.The UV-vis absorption peak was not obvious.Thirdly,the difference of crystal grown between COM and COD were investigated in pure aquatic system.The results indicated that COD have all been converted to COM in the third day. With the increase of growth time,the intensity of the diffraction peak of（（?）01） face was strengthened of COM crystals.The morphology of COM crystals in pure aquatic system are rectangle and irregular diamond.But the morphology of COD crystals changed from tetragonal bipyramid to hexagon in pure aquatic system.The growth of COD crystals has been the growth of control in pure aquatic system.The size of crystal increased with the increase of crystallization time.According to the theoretical derivation and growth model,the growth mechanism of nano-COD in pure aquatic system was given.The results in this study may provide new clues to investigate the formation mechanism of urinary stones.更多还原