共查询到18条相似文献,搜索用时 62 毫秒
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超分子结构草甘膦插层水滑石的组装及结构研究 总被引:14,自引:0,他引:14
提出了一种新的绿色农药缓释剂模型——超分子结构草甘膦缓释剂.依据插层组装理论,以阴离子层状材料镁铝水滑石(MgAl-LDH)为插层主体,以除草剂草甘膦为插层客体,由共沉淀法一步组装得到超分子结构草甘膦插层镁铝水滑石(MgAl-LDH-gly).通过对MgAl-LDH-gly的结构、主客体相互作用及化学组成确认,建立了MgAl-LDH-gly的近似超分子结构模型,并对其缓慢释放草甘膦的可行性进行了分析. 相似文献
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超分子结构姜黄素插层镁铝水滑石的组装、结构及缓释性能 总被引:2,自引:0,他引:2
以镁铝水滑石为主体, 以中药提取物姜黄素为客体, 由共沉淀法、离子交换法和焙烧复原法三种不同方法组装得到超分子结构复合材料——姜黄素插层镁铝水滑石. 并用XRD, IR, HPLC等手段对该材料进行了表征. 结果表明, 共沉淀法和离子交换法成功组装得到两种不同结构的姜黄素插层产物, 使材料的层间距扩大为0.82~1.36 nm, 层间客体姜黄素阴离子是以平行或者单层垂直的定位方向排列于层间的. 考察了该材料在不同pH值的磷酸盐缓冲溶液中的缓释性能, 其缓释历程为客体阴离子与介质中 的离子交换过程. 该研究指出了阴离子层状材料——水滑石在中药释释剂领域的应用潜力. 相似文献
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谷氨酸柱撑水滑石超分子结构层柱材料的插层组装 总被引:33,自引:1,他引:33
用返混沉淀方法实现了谷氨酸柱撑水滑石超分子结构层柱材料的插层组装,得到结晶度高、晶相单一且谷氨酸在层间有序排列的超分子结构层柱材料.用X射线衍射、原子光谱、元素分析、红外光谱及热重-差热分析表征了超分子结构层柱材料的结构,给出其结构模型. 相似文献
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以Mg(OH)2和NaAlO2为原料,采用新原料路线共沉淀法实现了柠檬酸根插层结构LDHs的超分子组装。用XRD、FT-IR、TG-DTA和元素分析等手段对样品进行分析表征。结果表明,新原料路线共沉淀法较常用的共沉淀法得到的柠檬酸根插层LDHs结晶度高、晶相单一,客体柠檬酸根在LDHs层间的排列高度有序。 相似文献
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超分子结构二氟尼柳插层镁铝水滑石的合成与表征 总被引:1,自引:0,他引:1
采用离子交换和共沉淀两种不同方法将二氟尼柳插入镁铝水滑石层间,得到一种新型的有机-无机层状复合材料。通过X射线粉末衍射、红外光谱、元素分析和热重-差热等手段对材料进行了表征。结果表明,离子交换法和共沉淀法成功地将二氟尼柳插入水滑石,得到的材料层状结构完整、晶相单一,且层间距均大于二氟尼柳分子尺寸,扩大为1.81~2.14 nm;二氟尼柳插入后,复合水滑石材料的热稳定性大幅度提高。客体二氟尼柳与主体层板之间存在超分子作用力,二氟尼柳分子的羧基与水滑石层板之间相互作用,以双层倾斜交替地排列于层板之间。此外,根据其超分子作用力建立了二氟尼柳插层镁铝水滑石的超分子结构模型。 相似文献
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采用共沉淀及离子交换的方法将高血压类药物卡托普利(Cpl)插入到Zn/Al-NO3-LDHs层间,借助XRD、FTIR、UV-Vis、TG-DTA和ICP等手段对样品进行表征。结果表明,Cpl阴离子可取代层间的NO3-,组装得到晶体结构良好的Cpl-LDHs。XRD结果表明得到的Cpl-LDHs的层间距为1.955~2.053 nm,并与根据PM3半经验分子轨道法优化计算得到的Cpl-三维尺寸进行比较,推测客体Cpl-是沿长轴方向与层板呈一定角度双层倾斜的方式交替排布于层间,与主体层板通过氢键与静电作用形成超分子结构;该超分子结构材料与卡托普利相比,其热稳定性及缓释性能得到较大提高;缓释实验数据符合Higuchi及Korsmeyer-Peppas扩散模型,说明本实验Cpl的释放很好的符合菲克扩散机理。 相似文献
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采用共沉淀法制备镁铝水滑石以及十二烷基苯磺酸钠(SDBS)插层水滑石,应用XRD、FT-IR、TG-DTA等手段表征合成水滑石的结构。实验研究表明:得到的镁铝水滑石(Mg-Al-NO3-LDHs)以及十二烷基苯磺酸钠插层水滑石(SDBS-LDHs)很好地保持了水滑石的层状结构,结构完整,晶相单一。研究表明共沉淀法可以成功地把十二烷基苯磺酸钠插入层状氢氧化镁铝层间,并使用分子动力学模拟方法模拟了插层复合物的微观结构,通过模拟得到的结果与实验测试结果接近。 相似文献
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ZHANG Qiang * LU Jie-binCollege of Materials Science Engineering Beijing University of Chemical Technology Beijing P. R. China 《高等学校化学研究》2002,18(4):424-426
IntroductionIt is well known that PVC is a kind of valuableplastic and used in many fields.But PVC isunstable against heat and light,and at the heat-molding step,the thermal decomposition of it maytake place.Finally,the decomposition will reducethe mechanical strength and lose otherproperties ofPVC.In order to overcome those disadvantages,athermal stabilizer is added in the PVC material toreduce the thermal decomposition,and organiccompounds of metals such as Sn,Pb,Ca,Ba,Znand Cd are u… 相似文献
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QU Huiqi PAN Longhai SUN Yuexin WANG Lei LI Yanyan ZHANG Mingjuan ZHANG Zhaoxiang LIN Haifeng 《高等学校化学研究》2020,36(6):1196-1202
Metronidazole(MTZ) is an important antibiotic, which has been widely applied to cure protozoal and bacterial diseases for human beings or animals. Herein, three novel drug supramolecular crystals constructed by MTZ with 2,5-dihydroxy-benzoic acid(2,5-DHBA)(1), 2,6-dihydroxy-benzoic acid(2,6-DHBA)(2) and 3,5-dihydroxy-benzoic acid(3,5-DHBA)(3), respectively, have been discovered. The hydrogen bonds of N-H···O(O-H···N), C-H···O and O-H···O play important roles in the 3D supramolecular framework formation for crystals 1-3. Interestingly, due to the vary locations of the substituent groups, the two-dimensional layers in crystals 1 or 2 are constructed via intermolecular hydrogen bonds between MTZ and 2,5-DHBA or 2,6-DHBA, while in crystal 3 water molecules play a significant role except the intermolecular hydrogen bonds between MTZ and 3,5-DHBA. In addition, five synthons of I R22(8), II R33(9) in crystal 1, III R12(4), IV R22(8) in crystal 2 and V R22(7) in crystal 3 formed through various hydrogen bonds are founded in this work. Systematic studies of syntheses, crystal structures and thermal analysis are reported. 相似文献
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通过离子交换反应将四足配体铕配合物[EuL(NO3)]2+[L=1,1,1’,1’-四(吡啶-2-羧酸酯基)联三甲基丙烷]插层组装到蒙脱土(MT)层板间, 制备出一种新型的超分子复合发光材料[EuL(NO3)]2+-MT. 用元素分析、XRD、FTIR、UV-Vis和热分析对材料进行了表征, 并对其荧光性质进行了研究. 结果表明, 复合材料保持了蒙脱土良好的层柱结构特征, 其层间距d(001)值与插层配离子的直径吻合得较好, 配离子以单层形式分布于蒙脱土层板间. 在紫外光激发下, 复合材料发出较强的Eu3+特征荧光, 其相对荧光强度、荧光单色性和荧光寿命大大优于相应配合物的乙醇溶液. 复合材料中配合物的发光性能、光稳定性和热稳定性较纯配合物有明显提高. 相似文献
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The electrostatic potential energy model of hydrotalcites was based on the theory of crystallography. The anionic potential energy of MgAl-hydrotalcites, with 20 layers and 2107 anions per layer, was calculated, and the anionic stability of the hydrotalcites was investigated. The charge density of the layer and the distance between the adjacent anions varied with the molar ratio of Al3+/(Mg2+ +Al3+). Anionic potential energy depended on the charge and size of the anions. Calculation results remained consistent with thermal stability and the ion exchange ability reported. This model is able to predict anionic stability of the hydrotalcites. 相似文献
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《Comptes Rendus Chimie》2014,17(6):586-596
The Cambridge Structural Database has been searched for supramolecular anions of the form HnXn + 1− where X is fluorine (n = 1 to 6) and chlorine (n = 1 to 5); no credible evidence was found for comparable bromine or iodine species. Several structural isomers have been identified, and an experimental measure has been developed which seems to distinguish between two-centre and three-centre bonded species. There are also examples of suprafluoride and suprachloride anions as ligands in organometallic complexes. Most of these anions have not been previously described. 相似文献
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以ZnAl-NO3-LDHs为前体,采用离子交换法将2-苯基苯并咪唑-5-磺酸(PBSA)插入到ZnAl-NO3-LDHs层间,借助XRD、FTIR、TG-DTA和UV-Vis等手段对样品进行表征。结果表明,PBSA阴离子可以完全取代前体层间的NO3-离子,组装得到晶体结构良好的ZnAl-PBSA-LDHs。对其结构进行研究发现,ZnAl-PBSA-LDHs中存在主体与客体以及客体与客体之间的相互作用,具有超分子结构特征。ZnAl-PBSA-LDHs在350 nm以下的紫外吸收能力较PBSA客体和ZnAl-NO3-LDHs前体显著增强,热稳定性也有所提高。将ZnAl-PBSA-LDHs以1.0%的质量比加入到聚丙烯(PP)中制备成ZnAl-PBSA-LDHs/PP薄膜,显著提高了PP的耐紫外光老化性能。 相似文献
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LIU Kun MENG Fan-xiaI MA Feng-xia CHEN Ya-guang 《高等学校化学研究》2007,23(4):391-394
The organo-inorganic hybrid compound [Ni(phen)3] [(H2W12O40){Ni(phen)2H2O} {Ni(trien)}]·2H2O was synthesized from Na2WO4·2H2O,NiSO4·6H2O,CH3COOK,triethylenetetramine and 1,10-phenanthroline in water by the hydrothermal reaction,and characterized by IR,X-ray single crystal diffraction,and TG-DTA analysis.This compound crystallized in the monoclinic system,space group P2(1)/n,with lattice constants:a=1.80998(6)nm,b=2.36504(8)nm,c=2.29199(7)nm,β=110.2220(10)°,V=9.2065(5)nm,Z=4.Final R indices R1=0.0532,wR2=0.1295.The compound is decomposed at 593 ℃. 相似文献