High-surface-area β-MnO2 nanoparticles exhibited high activity for the one-pot oxidative sulfonamidation of thiols to sulfonamides using O2 and NH3.
高比表面积的β-MnO2纳米颗粒在使用O2和NH3进行一锅式氧化磺酰胺化反应中表现出很高的活性。
Quinolylpropylpiperidine derivatives, their preparation and the compositions which comprise them
申请人:Aventis Pharma S.A.
公开号:US06403610B1
公开(公告)日:2002-06-11
Quinolylpropylpiperidine derivatives of formula (I)
which are particularly advantageous antimicrobial agents, their compositions, and their use.
配方(I)的喹诺啉丙基哌啶衍生物,特别有优势的抗微生物药剂,其组成成分和用途。
Synthesis of NaxMnO2+δ by a Reduction of Aqueous Sodium Permanganate with Sodium Iodide
作者:Y.U. Jeong、A. Manthiram
DOI:10.1006/jssc.2000.9003
日期:2001.2
Reduction of sodiumpermanganate with sodiumiodide in aqueous solutions has been investigated systematically. The products formed have been characterized by X-ray diffraction, wet-chemical analysis, and surface area and magnetic susceptibility measurements after firing at various temperatures. The results reveal that the sodium content x in the reduction products NaxMnO2+δ depends strongly on the
Structural evolution upon heating of sol–gel prepared birnessites
作者:O Prieto、M del Arco、V Rives
DOI:10.1016/s0040-6031(02)00503-8
日期:2003.5
texture assessment by nitrogen adsorption at −196 °C. The solids obtained are more crystalline than those prepared by oxidation with H2O2 in a basic medium. The samples are thermally stable and evolutionupon calcination at high temperature depends on the precise nature of the interlayer cation. So, calcination at 600 °C of a K-birnessite leads to formation of cryptomelane (2×2 tunnel structure), while
摘要 以葡萄糖和聚乙烯醇为还原剂,采用溶胶-凝胶法制备了夹层中含有K+和Na+的水钠锰矿。样品已通过元素化学分析、粉末 X 射线衍射、热分析(差示和热重分析)、FT-IR 光谱以及在 -196 °C 下通过氮吸附进行的比表面积和质地评估进行表征。获得的固体比在碱性介质中用 H2O2 氧化制备的固体更结晶。样品是热稳定的,在高温下煅烧时的演变取决于层间阳离子的精确性质。因此,K-水钠锰矿在 600 °C 下煅烧导致形成锂锰矿(2×2 隧道结构),而 Na 类似物导致形成具有不同隧道结构的混合 Mn-Na 氧化物。层间阳离子的离子交换在室温下局部发生;Li+ 容易进入夹层,而 Mg2+ 则更难进入,可能是因为它在水合状态下的稳定性高;在离子交换过程中增加温度和接触时间并不能极大地改善该过程。
Effect of MnO<sub>2</sub> Crystal Structure on Aerobic Oxidation of 5-Hydroxymethylfurfural to 2,5-Furandicarboxylic Acid
Aerobic oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA) as a bioplastics monomer is efficiently promoted by a simple system based on a nonprecious-metal catalyst of MnO2 and NaHCO3. Kinetic studies indicate that the oxidation of 5-formyl-2-furancarboxylic acid (FFCA) to FDCA is the slowest step for the aerobic oxidation of HMF to FDCA over activated MnO2. We demonstrate