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1.
以六水合硝酸钴、2-甲基咪唑为溶质,甲醇为溶剂,采用室温共沉淀法制备ZIF-67,并采用静电纺丝技术将ZIF-67掺杂在碳纤维中。研究了此负极材料的结构、形貌与电化学性能。由电子显微镜(SEM)、能谱分析(EDS)、综合热分析、X射线衍射(XRD)以及LAND电化学测试结果表明:以ZIF-67衍生的多孔钴氧化物碳纤维作为负极材料,具有较高比容量、良好的循环稳定性(在电流密度为100 mA·g-1时,100次循环后比容量仍具有597.7 mAh·g-1)。  相似文献   

2.
根据聚磷腈材料的生物可降解性、相容性等特性,以聚磷腈材料的生物可降解性、共聚、共混及复合等制备方法以及微球、纳米纤维和水凝胶等应用形式为主线,综述了自2000年以来国内外有关聚磷腈在生物医学材料领域的研究与进展概况。  相似文献   

3.
《广州化工》2021,49(16)
类沸石咪唑类金属有机骨架材料(ZIFs)是一种新型的多孔晶体材料,本文通过调控不同的金属比例制备了单金属以及双金属ZIF基氮掺杂碳材料,并研究了其电催化性能。通过调控六水合硝酸锌和六水合硝酸钴的比例得到了Co/Zn-ZIF,通过SEM和XRD观察到Co/Zn-ZIF的形貌以及晶体结构与ZIF-67基本相同,结果表明碳化后是一种非常好的石墨化碳材料。通过K-L方程得出,Co/Zn-ZIF-T的电子转移数达到了3.9,优于原始的ZIF-67-T,是理想的四电子反应路径,具有良好的ORR催化活性。  相似文献   

4.
文章采用悬浮聚合的方法合成氧氟沙星印迹微球,以氧氟沙星(模板分子)∶苯乙烯(功能单体)∶α-甲基丙烯酸(功能单体)∶二乙烯基苯(交联剂)摩尔比为1∶40∶40∶50,偶氮二异丁腈为1.5%,反应温度为80℃,反应时间为8 h。在最优条件下合成的印迹微球的吸附量为5.43mg.g-1,非印迹微球的吸附量为2.92 mg.g-1,印迹微球吸附性明显优于非印迹微球。  相似文献   

5.
采用辛醇和乳化剂(OS)作为复合分散剂,用悬浮聚合法制备了4-氨基吡啶分子印迹聚合物微球。采用无皂乳液聚合法对分子印迹聚合物种子微球的制备与性能进行了研究。结果表明,辛醇与极少数乳化剂复合使用,提高了乳液的稳定性,改善了种子微球粒径大小及粒径分布。当辛醇用量为单体质量的3.0%、丙烯酸乙醋与苯乙烯质量比为1:0.229、反应温度为85℃、pH值为8.0时,能够制备出期盼的分子印迹聚合物微球。  相似文献   

6.
为了提高多孔树脂微球的亲水性,扩大其应用范围,文章通过马来酸酐(MAH)与多孔苯乙烯-二乙烯基苯共聚微球悬挂双键的接枝聚合,制备了改性的多孔树脂微球。用扫描电镜、红外光谱法、酸碱滴定法等对产物进行了表征。考察了微球的交联度、引发剂、反应时间等因素对马来酸酐接枝率和改性微球形貌的影响。在以交联度55%的多孔微球为基球,基球与MAH质量比为5∶3,质量分数为3%的偶氮二异丁腈为引发剂,80℃、反应6 h时,制得了较好多孔形貌的改性微球。结果表明,马来酸酐为改性剂有利于保持多孔微球的多孔形貌。  相似文献   

7.
以苯乙烯(St)为单体、偶氮二异丁腈(AIBN)为引发剂、聚乙烯吡咯烷酮(PVP)为分散稳定剂,在乙醇-水反应介质中,采用分散聚合法制备了微米级单分散聚苯乙烯(PS)微球。分别用电镜扫描和激光粒度仪表征了PS微球表面形貌、粒径及粒度分布,探讨了影响PS微球粒径及粒度分布的诸多因素。结果表明,AIBN用量(以单体质量计,下同)大于5.0%或PVP用量(以单体质量计,下同)小于2%时,PS粒子间有聚并现象;当St浓度为10%、AIBN用量为2.5%、PVP用量为5.5%、醇水质量比为90∶10、聚合温度为70℃时,制备的PS微球粒径为1.612μm、粒度分散系数为0.357,微球单分散性及球形度最佳。  相似文献   

8.
以大蒜素为模型药物,采用复凝聚法制备了海藻酸钠/明胶/壳聚糖复合微球,考察了不同条件对微球溶胀性、载药性能和缓释性能等指标的影响。结果表明,明胶和海藻酸钠(质量比为1∶3)为2%,大蒜素投入量与混合胶比为1∶2时,制备的载药微球(DSGCM)外形规则,粒径分布在0.8~0.9mm之间,载药量为24.3%,包封率为69.4%,复合微球具有p H敏感性,在p H=7.4介质中微球溶胀率达到450%,药物释放过程符合Higuchi方程,明胶的加入可以延缓DSGCM复合微球的药物释放性能。  相似文献   

9.
采用羧甲基壳聚糖和海藻酸钠为基质原料,以戊二醛与氯化钙为复合交联剂,采用乳化交联法制备复合止血微球。以其溶胀率为指标,通过单因素实验研究复合止血微球制备的影响因素;基于单因素实验结果,采用BoxBehnken响应面法(RSM)优化制备工艺。结果表明,复合微球的最佳工艺条件为:羧甲基壳聚糖/海藻酸钠质量比为1∶1,5%氯化钙8 mL,乳化剂Span-80浓度2%。在此条件下,复合微球的溶胀率为302.62%,具有显著的体外促凝血活性。  相似文献   

10.
聚磷腈是一类新型无机有机复合功能高分子化合物,具有结构多样性,应用于航空航天、船舶制造、石油化工及生物医学等领域。介绍了聚磷腈的理化性质、用途、发展现状和制备方法。综述了聚磷腈的制备和性能研究进展。  相似文献   

11.
以NiCl2·6H2O和Co(NO3)2·6H2O为原料,CO(NH2)2为沉淀剂,Al2O3为载体,采用均匀沉淀法制备了负载型双金属催化剂(Ni-Co/γ-Al2O3).利用正交实验探讨了不同工艺参数对催化剂合成的影响,并得出了最佳制备工艺.实验得出的最佳工艺参数为:n(NiCl2·6H2O)/n(Co(NO3)2·...  相似文献   

12.
To effectively reduce the fire hazard of flexible polyvinyl chloride (PVC), this study explored the synthesis of perovskite-type copper hydroxystannate (CuSn(OH)6) microspheres by co-precipitation method. Then an organic–inorganic hybrid microsphere (CuSn(OH)6@PZS) with core-shell structure was fabricated by in situ coating with poly(cyclotriphosphazene-co-4,4′-sulfonyldiphenol) (PZS). The results showed that CuSn(OH)6@PZS performs most significantly in reducing the total heat release, while the CuSn(OH)6 alone achieves the best smoke suppression effect. The limiting oxygen index (LOI) value of the PVC composites is improved from 29.0% to a maximum of 35.3%. During combustion, the peak heat release rate (PHRR) and total smoke production (TSP) decrease by a maximum of 50.8% and 44.9%, respectively. Significantly, the presence of the PZS coating also improves the interfacial compatibility with PVC. The mechanical properties were significantly improved and the elongation at break improving by 40.9%.  相似文献   

13.
苯甲醛氧化制备苯甲酸的研究   总被引:4,自引:0,他引:4  
以氧气为氧化剂,在六水合氯化钴催化剂作用下,催化氧化苯甲醛制备苯甲酸,分别考察了温度、溶剂量、催化剂量、乳化剂量对苯甲酸收率的影响.在苯甲醛:水:乳化剂:六水合氯化钴质量比为75:50:37.5:0.075,反应温度75~80℃,反应时间6 h,氯气流量0.3 L/min下反应,产率在85%以上,用水进行两次重结晶,得率为60%~65%.  相似文献   

14.
Recently, a new type of phosphazene‐containing material, poly[cyclotriphosphazene‐co‐(4,4′‐sulfonyldiphenol)] (PZS), was successfully prepared. PZS materials including PZS nanotubes, PZS nanofibers and PZS microspheres show excellent thermal stability, biocompatibility and biodegradability. Moreover, PZS‐containing materials such as silver nanowire/PZS, carbon nanotube/PZS and Fe3O4/PZS nanotubes have also been prepared. Therefore, we explored a specific method for the functionalization of these PZS and PZS‐containing materials to expand their scope of application. As a model of various PZS and PZS‐containing materials, PZS microspheres (PZSMs) were functionalized via surface‐initiated atom transfer radical polymerization (ATRP). Polymerization of styrene occurred at surface sites covalently derivatized with ATRP initiators to form PZSM–polystyrene. The number‐average molecular weight (Mn) of grafted polymer chains could be well controlled. Furthermore, PZSM–polystyrene was still active for further block copolymerization of methyl methacrylate. Both styrene‐ and acrylate‐type monomers could be directly polymerized or block copolymerized from the surface of PZS and PZS‐containing materials using surface‐initiated ATRP. Mn of grafted polymer chains could be well controlled. This facile strategy could pave the way for a wider range of applications of these materials. Copyright © 2010 Society of Chemical Industry  相似文献   

15.
以拟薄水铝石、硝酸镍以及镁、钴、镧和铁的硝酸盐为原料,尿素为燃烧剂,采用尿素燃烧法制备系列镍基(以及含助剂)甲烷化催化剂。通过XRD和BET等对催化剂结构进行表征,采用固定床反应器评价催化剂的合成气甲烷化催化反应性能,考察Ni含量、尿素与原料质量比、焙烧温度和不同助剂等对催化剂结构和性能的影响,评价催化剂的稳定性。结果表明,Ni O质量分数为7.5%~44.8%时,采用尿素燃烧法均可制备γ-Al2O3为载体的镍基甲烷化催化剂,最佳制备条件为:尿素与原料质量比3∶1,焙烧温度450℃,燃烧时间40 min。26.1%Ni O/γ-Al2O3催化剂表现出较好的催化性能,在230℃和常压条件下,CO转化率和CH4选择性分别达99.5%和98.3%。26.1%Ni O-2.6%La2O3/γ-Al2O3催化剂在(230~700)℃经过多次升降反应温度和1 460 h的长周期稳定性测试,表现出较好的稳定性和耐热冲击性能。  相似文献   

16.
李雅泊  郑玉婴  刘阳龙 《化工学报》2016,67(10):4493-4499
以TiF4为钛源、九水合硝酸铁为掺杂前体,采用水热法制备铁掺杂的TiO2空心微球。采用SEM、TEM、XRD、BET、XPS等技术对样品的形貌、结构、晶型、比表面积、元素组成等进行表征,以亚甲基蓝(MB)的光催化降解为目标反应,评价其光催化活性。结果表明,160℃下水热反应生成的纳米TiO2空心微球晶型为锐钛矿,少量掺铁并不影响微球的形貌及晶体结构。光催化实验表明,160℃下水热反应12 h生成的TiO2空心微球样品均匀性好、光催化活性最佳;铁掺杂能显著提高TiO2空心微球的催化活性,当铁钛比为1.5:100时,所得样品粒径最小,比表面积最大,光催化活性最高。  相似文献   

17.
均匀沉淀法制备纳米氧化镍及其工艺优化   总被引:4,自引:0,他引:4  
为研制生物质气化用纳米N iO催化剂,文中以六水合硝酸镍为原料、尿素为沉淀剂,采用均匀沉淀法制备了纳米N iO,并利用TGA,XRD,TEM等分析手段对前驱体和产品的性能进行了表征。同时,探讨了制备条件对产品粒径和产率的影响,得出了最佳工艺条件:反应物n(六水合硝酸镍)/n(尿素)=1∶3,沉淀反应温度和时间分别为115℃和2.5 h,煅烧温度400℃,煅烧时间1 h。最佳条件下所得纳米N iO粒子呈球形,分散性好,纯度较高,属立方晶系结构,平均粒径约为7.5 nm。  相似文献   

18.
Zeolitic imidazolate framework-8 (ZIF-8) was prepared through a solve-thermal reaction method and then shaped using different additives. The influence of the shaping conditions on the microstructure of the shaped samples was characterized by the XRD, BET, and SEM techniques. The results demonstrate that the compressive strength of the various shaped tablets is greatly increased and capable of meeting the industrial requirements compared to the unshaped ZIF-8 and that the loss rate of specific surface areas was maintained at 10%after the addition of 10%(by mass) binder and 10%(by mass) solvent. The adsorption isotherms of CO2, CH4, C3H8, and C3H6 on powdery ZIF-8 and the shaped tablets (T-shaped ZIF-8, C-shaped ZIF-8, and N-shaped ZIF-8) were determined through volumetric measurements under different pressures and temperatures (298.2, 323.2, and 348.2 K). The adsorption capacities of the gases on both the ZIF-8 powder and the shaped tablets fol ow the order C3H6 N C3H8 N CO2 N CH4. Furthermore, the results show that the adsorption capacities of the gases on the shaped tablets are lower by approximately 10%–20%than those on the powdery ZIF-8. In fact, the adsorption equilibrium isotherms for CO2, CH4, C3H8, and C3H6 on both powdery and shaped ZIF-8 can be wel described by the Langmuir equation.  相似文献   

19.
李甲  谷景华  殷文杰  李泽耀 《化工学报》2018,69(8):3724-3731
ZIF-8因具有0.34 nm的孔道直径而被认为是最具应用前景的气体分离膜材料之一。不锈钢网(SSN)作为分离膜的支撑体具有价格低廉、易于裁剪、厚度薄等优点。采用水热法在SSN表面生长ZnO缓冲层,以ZnO修饰的SSN(ZnO/SSN)为支撑体制备ZIF-8膜。采用X射线衍射(XRD)和扫描电子显微镜(SEM)对合成的ZIF-8膜进行表征,并进行了气体渗透性能测试,结果表明,在ZnO颗粒修饰后的SSN支撑体上无需活化可制备出单一物相、无缺陷的ZIF-8膜;在室温(298 K)下,ZIF-8膜的H2/CO2、H2/N2、H2/CH4的理想分离系数分别为7.3、9.2、12.4;在150℃,ZIF-8膜的渗透性能稳定。  相似文献   

20.
ZIF-8@super-macroporous poly(glycidyl methacrylate) (SM-PGMA) microspheres were synthesized. The SM-PGMA microsphere was a novel material with high surface areas and large pore size. Here, ZIF-8 was loaded effectively both on the surface and inside of the macro-pores of microspheres by a facile way. The ZIF-8@SM-PGMA microspheres were characterized by SEM, TEM, XRD and FTIR. Additionally, they were used as an adsorbent material for the adsorption of phenol from aqueous solutions. The results indicated that the ZIF-8@SM-PGMA microspheres possessed apparently higher adsorption capacity for phenol than that of SM-PGMA microspheres. The ZIF-8@SM-PGMA microspheres obtained in this study have great potential for adsorption, separation, catalysis etc.  相似文献   

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