铝土矿地质研究中分析技术应用进展

目前,扫描电子显微镜( SEM)、电子探针(EPMA)、X射线衍射分析仪(XRD)、电感耦合等离子体质谱(ICP - MS)、X射线荧光光谱(XRF)等技术都已运用于铝土矿的矿物分析及化学成分测定.这些现代分析方法的使用为铝土矿的地质研究提供了更准确和快速的技术支持.本文较详细归纳总结了铝土矿分析技术以及其在地质研究中...     

Dual elemental modulation in cationic and anionic sites of the multi-metal Prussian blue analogue pre-catalysts for promoted oxygen evolution reaction

Designing advanced electrocatalysts for the oxygen evolution reaction (OER) is of great significance owing to its crucial role in facilitating the production of clean hydrogen energy via water splitting. To date, it has been widely accepted that a pre-oxidation process with the in-situ generation of the catalytically active high-valence metal sites is essential for promoting the OER behavior of most transition-metal-based OER catalysts, or more felicitously speaking, pre-catalysts. Hence, exploring such pre-catalysts with high pre-oxidation reactivity is of high promise. Herein, we proposed the dual elemental modulation in the cationic and anionic sites of the multi-metal Prussian blue analogue (PBA) pre-catalysts, resulting in promoted OER behavior benefitted from the efficient pre-oxidation ability as well as the multi-metal synergy. Detailed investigations indicate that the Co-containing multi-metallic cations and mixed Fe^IIICo^III cyanide anions in NiCuCo^II–Fe^IIICo^III PBA (denoted as NiCuCo^II–Fe^IIICo^III) are beneficial to OER catalysis owing to the high intrinsic activity guaranteed by the local Co³⁺ active sites as well as the optimal multi-metal synergy. After the facile pre-oxidation process, additional high-valence Ni, Cu and Fe ions can be in-situ formed and serve as the active sites, thereby resulting in significantly improved OER behavior. For example, the OER current density of NiCuCo^II–Fe^IIICo^III exhibits 1.81 times enhancement even after 72 ?h continuous OER catalysis, and the required overpotential for 10 ?mA ?cm^?2 reduces from 288 ?mV for the fresh pre-catalyst to a remarkable record of 251 ?mV after the pre-oxidation-induced activation, making the optimal PBA-based catalyst a promising candidate for efficient and durable water electrolysis.     

浅析活性低聚糖食品的开发

活性低聚糖不能被人体消化道内酶系酶解,而直接进入大肠内为双歧杆菌所利用,是肠道有益茵群的有效增殖因子。活性低聚糖因其独特的生理功能,在国外已成为一类重要的保健食品基料。本文就活性低聚糖食品的营养保健作用和开发利用进行了初步阐述。     

建筑结构电液伺服主动抗振系统最优控制

分析了线性二次型最优控制是适用于电液伺服主动抗振系统的原因，并根据电液伺服抗振系统特点，提出了以伺服阀ｐ－Ｑ特性为不等式约束条件的瞬时最优控制方法，抗振模拟试验结果证实了这一控制思想的正确性和有效性。