The Ni-W-WC composite-coating electrode was prepared by electrolytic compos- ite-deposition. The characterization for the hydrogen evolution reaction(HER) was compared in 7 mol· L -1 KOH solution by steady-state ...The Ni-W-WC composite-coating electrode was prepared by electrolytic compos- ite-deposition. The characterization for the hydrogen evolution reaction(HER) was compared in 7 mol· L -1 KOH solution by steady-state polarization and AC impedance technique. The results show that the composite-coating electrode is catalytically more active than Ni-W electrode. The electro- catalytic activities of the composite-coating electrode are attributed to the increase in the real surface areas and the decrease in the standard free energy of activation. The stability test of the compos- ite-coating electrode shows excellent stability during long-term continuous electrolysis and good re- sistance against frequent power interruption on this electrode.展开更多
Isoamyl isovalerate has been synthesized by using solid superacid SO 2- 4/TiO 2 as catalyst.The effect of catalyst,activation temperature,ratio of acid to alcohol,reaction time to the productivity of ester was studied...Isoamyl isovalerate has been synthesized by using solid superacid SO 2- 4/TiO 2 as catalyst.The effect of catalyst,activation temperature,ratio of acid to alcohol,reaction time to the productivity of ester was studied.The experimental results show that the yield of ester is 82.9% in optimum conditions,the quality of product is in consistance with GB6778-86 standardization.展开更多
The Co WC composite coating electrode was prepared by electrolytic composite deposition. Its electrocatalytic activity in hydrogen evolution has been examined in a 7 mol/L KOH solution by steady state polarization and...The Co WC composite coating electrode was prepared by electrolytic composite deposition. Its electrocatalytic activity in hydrogen evolution has been examined in a 7 mol/L KOH solution by steady state polarization and AC impedance technology. The results show that the composite coating is catalytically more active than Co electrode due to the increase in its real surface areas and the decrease in the standard free energy of activation. The electrode shows an excellent stability in long term electrolysis and good resistance against power interruption.展开更多
To prepare the adherent and high active platinum black plated titanium electrode,ultrasonic agitation technology was adopted during the electrodeposition.Ultrasonic agitation technology enhanced the activity of electr...To prepare the adherent and high active platinum black plated titanium electrode,ultrasonic agitation technology was adopted during the electrodeposition.Ultrasonic agitation technology enhanced the activity of electrode,improved the cohesion between coatings and substrate,changed the microscopical surface shape and increased the real surface area of electrode.The enhancement of the activity of electrode was in large due to the electrode rugosity.展开更多
淀粉基(starch-based)材料是一类重要的生物降解聚合物,羟基磷灰石(HA)是人体骨骼的主要成分,以淀粉基材料为基体、以 HA 为增强材料的 HA/淀粉基复合材料是一类新型的复合生物材料,其具有良好的生物相容性,在骨修复领域具有巨大的应用...淀粉基(starch-based)材料是一类重要的生物降解聚合物,羟基磷灰石(HA)是人体骨骼的主要成分,以淀粉基材料为基体、以 HA 为增强材料的 HA/淀粉基复合材料是一类新型的复合生物材料,其具有良好的生物相容性,在骨修复领域具有巨大的应用潜力。初步对该复合材料进行了归类,并介绍了其制备工艺、性能和应用等方面的研究近况,指出改进复合工艺、采用纳米级 HA 增强并进行表面改性是其发展趋势。展开更多
羟基磷灰石(HA)被认为是目前最有吸引力的骨组织替代材料,与纯 HA 相比,碳磷灰石(CHA)在化学组成上更接近于人骨和牙齿等硬组织,且具有更好的生物相容性和更高的骨传导性,因此有望成为新型的骨组织替代材料。综述了目前国内外关于碳磷...羟基磷灰石(HA)被认为是目前最有吸引力的骨组织替代材料,与纯 HA 相比,碳磷灰石(CHA)在化学组成上更接近于人骨和牙齿等硬组织,且具有更好的生物相容性和更高的骨传导性,因此有望成为新型的骨组织替代材料。综述了目前国内外关于碳磷灰石的研究,主要介绍了 CHA 中碳酸根的取代类型、机理及制备方法,碳酸根的取代对 HA 结构及各方面性能的影响,以及碳酸根含量的测定等,并指出仿生法合成 CHA 及其复合材料是最新的研究热点,也是今后骨植入材料研究中的一个重要方向。展开更多
文摘The Ni-W-WC composite-coating electrode was prepared by electrolytic compos- ite-deposition. The characterization for the hydrogen evolution reaction(HER) was compared in 7 mol· L -1 KOH solution by steady-state polarization and AC impedance technique. The results show that the composite-coating electrode is catalytically more active than Ni-W electrode. The electro- catalytic activities of the composite-coating electrode are attributed to the increase in the real surface areas and the decrease in the standard free energy of activation. The stability test of the compos- ite-coating electrode shows excellent stability during long-term continuous electrolysis and good re- sistance against frequent power interruption on this electrode.
文摘Isoamyl isovalerate has been synthesized by using solid superacid SO 2- 4/TiO 2 as catalyst.The effect of catalyst,activation temperature,ratio of acid to alcohol,reaction time to the productivity of ester was studied.The experimental results show that the yield of ester is 82.9% in optimum conditions,the quality of product is in consistance with GB6778-86 standardization.
文摘The Co WC composite coating electrode was prepared by electrolytic composite deposition. Its electrocatalytic activity in hydrogen evolution has been examined in a 7 mol/L KOH solution by steady state polarization and AC impedance technology. The results show that the composite coating is catalytically more active than Co electrode due to the increase in its real surface areas and the decrease in the standard free energy of activation. The electrode shows an excellent stability in long term electrolysis and good resistance against power interruption.
文摘To prepare the adherent and high active platinum black plated titanium electrode,ultrasonic agitation technology was adopted during the electrodeposition.Ultrasonic agitation technology enhanced the activity of electrode,improved the cohesion between coatings and substrate,changed the microscopical surface shape and increased the real surface area of electrode.The enhancement of the activity of electrode was in large due to the electrode rugosity.
文摘淀粉基(starch-based)材料是一类重要的生物降解聚合物,羟基磷灰石(HA)是人体骨骼的主要成分,以淀粉基材料为基体、以 HA 为增强材料的 HA/淀粉基复合材料是一类新型的复合生物材料,其具有良好的生物相容性,在骨修复领域具有巨大的应用潜力。初步对该复合材料进行了归类,并介绍了其制备工艺、性能和应用等方面的研究近况,指出改进复合工艺、采用纳米级 HA 增强并进行表面改性是其发展趋势。
文摘羟基磷灰石(HA)被认为是目前最有吸引力的骨组织替代材料,与纯 HA 相比,碳磷灰石(CHA)在化学组成上更接近于人骨和牙齿等硬组织,且具有更好的生物相容性和更高的骨传导性,因此有望成为新型的骨组织替代材料。综述了目前国内外关于碳磷灰石的研究,主要介绍了 CHA 中碳酸根的取代类型、机理及制备方法,碳酸根的取代对 HA 结构及各方面性能的影响,以及碳酸根含量的测定等,并指出仿生法合成 CHA 及其复合材料是最新的研究热点,也是今后骨植入材料研究中的一个重要方向。
