Metal‐Free Autoxidative Nitrooxylation of Alkenyl Oximes with Molecular Oxygen

A metal‐free aerobic autoxidative nitrooxylation of alkenyl oximes mediated by tert‐butyl nitrite is described. Molecular oxygen is used as the oxidizing reagent, avoiding use of organic trapping reagents such as 2,2,6,6‐tetramethylpiperidine 1‐oxyl (TEMPO). The desired products were obtained in generally high yields.

     

Palladium‐Catalyzed Oxidative Carbonylation of Aromatic C−H Bonds with Alcohols using Molybdenum Hexacarbonyl as the Carbon Monoxide Source

With molybdenum hexacarbonyl as the carbon monoxide source, a general palladium‐catalyzed carbonylative transformation of the C−H bond on aromatic rings to produce esters has been developed. Good yields of the corresponding products have been obtained with wide functional group tolerance and excellent regioselectivity. A variety of aliphatic alcohols are suitable reactants here.

     

Enantioselective One‐Pot Reaction: Organocatalyzed Synthesis of Fully Functionalized Oxabicyclo[2.2.2]octanes with Seven Contiguous Stereocenters

An enantioselective one‐pot Michael/Michael/Henry/hemiacetalization reaction between α,β‐unsaturated aldehydes, α‐ketoamides, and nitroalkenes under mild conditions catalyzed by a diarylprolinol silyl ether has been developed. The sequential methodology provides a direct approach to a wide range of fully substituted chiral oxabicyclo[2.2.2]octanes with seven contiguous stereocenters in moderate to excellent yields (up to 99%), high to excellent diastereoselectivities (up to >25:1 dr), and high to excellent enantioselectivities (up to 99% ee).

     

磷化工"双废"联用工艺研究

以磷化工"双废"——磷石膏、磷尾矿为原料,通过硫酸循环酸浸磷尾矿,经盐酸分解磷尾矿、碳化磷石膏、转晶、酸化、析钙、析磷、浓缩、析镁等过程,得到了转化率为96.94％ 的CaCO 3,CaO质量分数为23.38％ 的二水石膏,MgO质量分数为8.27％、P2O5质量分数为23.89％、氮质量分数为6.83％ 的氮镁磷肥,氮质量分数为23.76％ 的氯化铵以及M g O质量分数为30.04％ 的碳酸镁等,所得产品均符合工业应用要求.讨论了循环酸浸过程中离子浓度的变化情况,为联合处理磷石膏、磷尾矿提供了新思路.     

Catalyst-Controlled Selectivity in Oxidation of Olefins: Highly Facile Success to Functionalized Aldehydes and Ketones

Catalysis Letters - The attractive challenge in green chemistry is exploring novel heterogeneous catalyst system for catalyst-controlled product selectivity for oxidation of olefins. Hence, we...     

Quench Sensitivity of AA7N01 Alloy Used for High-Speed Train Body Structure

JOM - The quench sensitivity of AA7N01 aluminum alloy used for high-speed train body structure was investigated by end-quenching test, time–temperature-transformation curves simulation,...     

内陆核电厂液态流出物液转气排放可行性初探

本文针对我国缺乏受纳水体区域核电厂选址和建设的瓶颈问题,以冀东核电厂址和国内某典型内陆厂址为例,对液态流出物液转气排放的源项、工艺及环境影响开展了一些研究工作,从公众剂量评价的角度,初步论证了液转气排放技术路线的可行性,为我国缺乏受纳水体区域核电厂的选址、建设和监管提供参考。     

次临界反应性测量方法研究

压水堆启动前需要进行物理启动试验,其中调临界是相对耗时的一部分。采用次临界条件下的试验,可以省去调临界的步骤,提高物理启动试验的安全性和适用性,加速物理启动试验的进程,提高压水堆的负荷因子。目前,次临界反应性测量受限于测量信号较弱,背景噪声强,误差较大,难以满足商用压水堆的工程应用要求。本文基于源倍增方法,利用空间重要性修正因子和信号线性修正提高次临界反应性测量的精度,成功地在核电厂首循环上实现了次临界反应性测量的蒙特卡罗方法计算,取得了较好的计算精度与效果。