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1.
Porous sol-gel glass of CaO-SiO2-P2O5 system with macropores larger than 100 μm was prepared by adding stearic acid as pore former when the sintering was carried out at 700 ℃ for 3 h. The sol-gel porous glass shows an amorphous structure. The diameter of the pore created by pore former varies from 100 to 300 μm, and macroporous glass has a narrow and small pore size distribution in mesoporous scale. The porosity and pore size ofmacroporous bioactive glass can be controlled.  相似文献   

2.
The phase separation and gel formation behavior in an alkoxy-derived silica sol-gel system containing Ci6EOi5 has been investigated. Various gel morphologies similar to other sol-gel systems containing organic additives were obtained by changing the preparation conditions. Micrometer-range interconnected porous gels were obtained by freezing transitional structures of phase separation in the sol-gel process. The dependence of the resulting gel morphology on several important reaction parameters such as the starting composition, reaction temperature and acid catalyst concentration was studied in detail. The experimental results indicate that the gel morphology is mainly determined by the time relation between the onset of phase separation and gel formation.  相似文献   

3.
The effect of glass ionomer cement and resin-modified glass ionomer cement incorporated with chlorhexidine and bioactive glass on antimicrobial activity and physicochemical properties were investigated.The experimental results showed that groups incorporated with 1% chlorhexidine exhibited a significant reduction of optical density values of the bacterial suspension and increased the degradation of Streptococcus mutans biofilm.However,groups incorporated with 10% bioactive glass did not affect the optical density values and the biofilm formation.The mechanical properties of the materials and the polymerization were not influenced by the addition of chlorhexidine.Nevertheless,the compressive strength was lower when the materials were incorporated with bioactive glass.It can be concluded that glass ionomer cements incorporated with chlorhexidine can maintain its mechanical properties as well as reduce early S mutans biofilm formation.Controlled release/sustained release technology may be required to optimize the antibacterial activity of glass ionomer cements incorporated with bioactive glass.  相似文献   

4.
以锰铁渣和碎玻璃为主要原料,碳粉为发泡剂,硼砂为助熔剂,采用粉体烧结研制出了泡沫玻璃。对泡沫玻璃的表观密度和吸水率进行了测定。研究结果表明,当锰铁矿渣用量在12.5%~20%时,控制好工艺参数,可以制备出表观密度为407 kg/m3的泡沫玻璃。  相似文献   

5.
以锰铁渣和碎玻璃为主要原料,碳粉为发泡剂,硼砂为助熔剂,采用粉体烧结研制出了泡沫玻璃。对泡沫玻璃的表观密度和吸水率进行了测定。研究结果表明,当锰铁矿渣用量在12.5%~20%时,控制好工艺参数,可以制备出表观密度为407 kg/m3的泡沫玻璃。  相似文献   

6.
1Introduction Sol gelmethod,servingasoneoftheadvancedsyn thesizingmethodsforbioactivematerials,hasrecently beenmadegreatprogress.Typicalexamplesofthebioac tivematerialsmadebythismethodincludethebioactive glassbyZhong[1]etalandbioactiveglass ceramicsby Abi…  相似文献   

7.
基于溶胶凝胶法的TiO_2溶胶的制备   总被引:1,自引:0,他引:1  
用N-N二甲基乙酰胺(DMAC)作溶剂,钛酸丁酯作前驱物,冰乙酸为稳定剂,通过溶胶凝胶法制得了二氧化钛(TiO2)溶胶,并且对加水方式、加水量、溶剂量、pH值、温度等影响因素进行了考察。结果表明,当采用分散加水方式,温度在25℃~35℃以下,DMAC与钛酸丁酯的体积比为3.5:1,V(H2O)/V(Ti(OC4H9)4)为2~3,pH值为2~4时所得TiO2溶胶稳定,透明性好,可用作聚合物与纳米二氧化钛复合膜的研制的添加剂。  相似文献   

8.
Both silica and boron-silica glass materials doped with terbium organic complex were prepared by in situ sol-gel method respectively. XRD and SEM measurements were performed to verify the non-crystalline structure of the glass. The influence of the glass contents on the structure of the glass and the erwrgy level of the doped Tb (Ⅲ) ions was analyzed by the emission spectra and IR spectra. The effect of B2O3 on the photolumirwscence properties of rare earth organic complex in silica- based glass was investigated. The IR spectra indicate that the in situ sylthesized rare earth complex molecule was confined to the micropores of the bost and the vibration of the ligands was frozen. When B2O3 was added into the silica host gel, B2O3 had little influence on the noncrystallirw structure of the glass, and BO3 triangle, which had a layer structure different from the silica framework, could form. So the silica network became more inhomogenous, and the luminescence of terbium complexes was quenched with the increase of the B2O23 amount.  相似文献   

9.
The citrate gel of (Bi, Pb), Sr, Ca and Cu and the (Bi, Pb)-Sr-Ca-Cu-(O, F) superconductor were prepared using citrate as the organic complex agent and 2-ethyl hexanol as the dehydrating agent. The starting material was a high-purity nitrate solution containing the desired ions in the appropriate atomic ratio. The optimum temperature and pH to obtain the homogeneous gel precursor were estimated. IR and DSC were employed to study the thermal decomposition and the calcination of the precursor material. After the calcined powder was sintered, a nearly single-phase (Bi, Pb)2Sr2Ca2Cu3O x superconductor with the transition temperature 105 K was synthesized. The effect of the doping of Pb and F was also studied in the paper. Synopsis of the first author Yin Zhoulan, associated professor, born in 1965, received Ph D degree in 1994, professional interest is physical chemistry in metallurgy and materials.  相似文献   

10.
以正硅酸乙酯(TEOS)、硝酸钙[Ca(NO3)2·4H2O]为原料,采用溶胶 凝胶法制备了CaO SiO2干凝胶粉末。在适当的条件下制备粒径为0.2~1.0μm的硅灰石粉体。研究发现热处理温度、时间对粉体粒度有较大影响。采用DTA、XRD等研究了CaO SiO2凝胶粉末在热处理过程中的物理、化学变化及晶相转变,并通过TEM观察了干凝胶粉末热处理产物的形貌。  相似文献   

11.
溶胶—凝胶法制备硅灰石超细粉体   总被引:5,自引:0,他引:5  
以正硅酸乙酯(TEOS)、硝酸钙[Ca(NO3)2·4H2O]为原料,采用溶胶 凝胶法制备了CaO SiO2干凝胶粉末。在适当的条件下制备粒径为0.2~1.0μm的硅灰石粉体。研究发现热处理温度、时间对粉体粒度有较大影响。采用DTA、XRD等研究了CaO SiO2凝胶粉末在热处理过程中的物理、化学变化及晶相转变,并通过TEM观察了干凝胶粉末热处理产物的形貌。  相似文献   

12.
以乙酸锰和乙酸锂为金属源,间苯二酚和甲醛为分散剂,柠檬酸为络合剂,采用溶胶凝胶法成功制备具有网状结构的锰酸锂粉体.通过XRD、SEM、TEM、循环伏安等测试手段对产物进行了表征,并探究了甲醛的加入量和体系PH对其晶相结构和形貌的影响.实验结果表明:制备的锰酸锂晶粒尺寸在几十个纳米左右,并且当甲醛的加入量为9mL、体系pH为8时,锰酸锂粉体表现出高的纯度、优异的结晶性能以及密集而巨大的面网结构.其循环伏安测试结果表明,其载流子传递、转移方面性能优良,可能因其结晶性能优良,本身所具有的独特的网络结构可以提供更多的嵌锂空间,并且缩短离子扩散路径.  相似文献   

13.
Autoigniting synthesis of gel from Ba(NO3)2,TiO(NO3)2 and C6H8O7.H2O aqueous solution was investigated at an initial temperature of 600℃ and tetragonal BaTiO3 nanopowder with particle size of 80nm was prepared.It is indicated that the specific surface area of the combustion product before and after calcination is 14.74m^2/g and 12.49m^2/g,respectively.The combustion wave is composed of solid phase reaction zone and gaseous phase flame reaction zone.The combustion flame temperature is 1123K derived from thermo couple measurement.The characteristics and densification behavior of the sol-gel autoigniting synthesized BaTiO3 nanopowder were in vestigated.  相似文献   

14.
采用溶胶凝胶法制备了二茂铁微粒后,将所得二茂铁微粒超声分散于甲基三甲氧基硅烷形成的溶胶结构中,得到了溶胶凝胶固载的二茂铁纳米粒子,并制成化学修饰碳糊电极.采用扫描电镜(SEM)方法对制得粉体微粒进行表征,并通过循环伏安实验与计时安培实验测试修饰电极的电催化活性.结果表明:采用溶胶凝胶法分散的二茂铁纳米粒子,粒径约为300nm,将二茂铁固载于SiO2的凝胶结构中有效地提高了修饰电极的稳定性与二茂铁的分散性.在优化的实验条件下,修饰电极对抗坏血酸(AA)的氧化具有明显的催化作用,安培法检测AA的线性范围为3.0×10-6~2.5×10-3 mol/L,检出限为1.0×10-6 mol/L(3sb,n=10).  相似文献   

15.
归纳了SOL-GEL法制有机/无机纳米复合材料(ONIC)的复合方法,如:有机聚合物存在下形成无机相纳米粒子;无机纳米相存在下进行有机单体聚合;无机溶胶与有机聚合物溶液共混,再凝胶化,用杂交法将有机单体与无机溶胶同步聚合形成互贯网络,这种复合材料的最大结构特点是微区的大小在纳米尺寸范围内,也可是互相贯穿的,其材质是高度透明的,耐热,热分解温度和力学强度比纯聚合物有较大的提高。  相似文献   

16.
基于溶胶凝胶法ITO薄膜材料的制备与表征   总被引:1,自引:0,他引:1  
基于溶胶凝胶法制备了掺铟二氧化锡(ITO)薄膜,探讨聚乙二醇(PEG)、退火温度、退火过程氧气浓度等因素对ITO薄膜性能的影响。实验结果表明:在相同实验条件下,添加PEG能够降低ITO薄膜表面粗糙度,退火温度会改变ITO薄膜的结晶度,提高含锡量和氧浓度会增加ITO薄膜的电阻率。本研究为ITO埋栅结构气敏传感器制备提供了实验基础。  相似文献   

17.
用N-N二甲基乙酰胺(DMAC)作溶剂,钛酸丁酯作前驱物,冰乙酸为稳定剂,通过溶胶凝胶法制得了二氧化钛(TiO2)溶胶,并且对加水方式、加水量、溶剂量、pH值、温度等影响因素进行了考察.结果表明,当采用分散加水方式,温度在25℃~35℃以下,DMAC与钛酸丁酯的体积比为3.5:1,V(H2O)/V(Ti(OC4H9)4...  相似文献   

18.
以五氯化钽为反应前驱体,三嵌段两性聚合物P123做天然模板,用溶胶凝胶法制备出了介孔五氧化二钽薄膜.经过SEM检测分析,薄膜厚度约为200nm.XRD研究结果表明,制得的薄膜具有明显的介孔结构,经TEM检测可以观察到孔洞结构;得到的五氧化二钽薄膜经过400℃煅烧1h,介孔结构仍然得到保留.  相似文献   

19.
溶胶凝胶法制备氧化亚铜薄膜及其工艺条件   总被引:2,自引:0,他引:2  
以单质锂、无水甲醇和氯化铜为原料,葡萄糖为还原剂,醋酸为络合剂,采用溶胶 凝胶法在玻璃基片上制备Cu2O薄膜,并确定了制备的工艺条件:CH3OH及CuCl2·2H2O为原材料,C6H12O6·H2O为还原剂,CH3COOH为络合剂。通过X射线衍射仪、紫外 可见分光光度计和扫描电镜等分析和表征,确定了影响Cu2O薄膜性质的因素。结果表明:用溶胶 凝胶法可以制备具有良好性能的Cu2O薄膜。  相似文献   

20.
采用溶胶-凝胶技术制备了二氧化硅-氧化锌-硅橡胶固相微萃取涂层,通过扫描电子显微镜观察了涂层的表面性貌。应用顶空固相微萃取-气相色谱联用技术分析了水中三氯乙烯和四氯乙烯,检出限分别为0.22 mg·L^-1和0.30 mg·L^-1,线性相关系数(R)分别为0.999 1和0.994 4,6次测定的相对标准偏差分别为4.21%和3.92%。  相似文献   

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