A novel polymer-bound 1,2-diol, 3-polystyrylsulfonyl-1,2-propanediol (6) had been prepared by the reaction of sodium polystyrylsulfinate with allyl bromide, followed by oxidation and. hydrolysis or directly with 3-chl...A novel polymer-bound 1,2-diol, 3-polystyrylsulfonyl-1,2-propanediol (6) had been prepared by the reaction of sodium polystyrylsulfinate with allyl bromide, followed by oxidation and. hydrolysis or directly with 3-chloro-1,2-propanediol in the presence of a phase transfer catalyst, n-tetrabutylammonium iodide. The capacity of resin 6 for terephthaidehyde reached 1.43 mmol/g. The aldehydic groups attached to polymer 6 reacted with hydroxylamine hydrochloride or reduced by sodium borohydride giving p-formylbenzaldoxime (yield: 89%)and p-formyl-benzalcohol (yield: 734%), respectively. The high yields of these polymer-supported reactions showed that the polymer 6 possessed the effective isolation of its reactive sites.展开更多
起重电磁铁主要用于各种钢材的运输。电磁铁停电保磁系统既是起重电磁铁作业的馈电整流设备,又能作为起重作业现场的安全保障系统。在基于双向DC-DC变换器的电磁铁停电保磁系统中,本文为了提升双向DC-DC变换器的效率,提出一种基于线性...起重电磁铁主要用于各种钢材的运输。电磁铁停电保磁系统既是起重电磁铁作业的馈电整流设备,又能作为起重作业现场的安全保障系统。在基于双向DC-DC变换器的电磁铁停电保磁系统中,本文为了提升双向DC-DC变换器的效率,提出一种基于线性控制的改进PWM移相控制策略,使变换器在宽电压和全负载范围内实现所有开关管零电压开关(Zero Voltage Switching,ZVS),且有效减小电感电流有效值,从而实现变换器整体效率的提升。实验结果表明,基于线性控制的改进PWM移相控制策略使双向DC-DC变换器的整体效率得到了提高,电磁铁停电保磁系统减少了设备体积,提高了可靠性,降低了能耗,提升了效率。展开更多
基金The project is supported by the National Natural Science Foundation of China.
文摘A novel polymer-bound 1,2-diol, 3-polystyrylsulfonyl-1,2-propanediol (6) had been prepared by the reaction of sodium polystyrylsulfinate with allyl bromide, followed by oxidation and. hydrolysis or directly with 3-chloro-1,2-propanediol in the presence of a phase transfer catalyst, n-tetrabutylammonium iodide. The capacity of resin 6 for terephthaidehyde reached 1.43 mmol/g. The aldehydic groups attached to polymer 6 reacted with hydroxylamine hydrochloride or reduced by sodium borohydride giving p-formylbenzaldoxime (yield: 89%)and p-formyl-benzalcohol (yield: 734%), respectively. The high yields of these polymer-supported reactions showed that the polymer 6 possessed the effective isolation of its reactive sites.
文摘起重电磁铁主要用于各种钢材的运输。电磁铁停电保磁系统既是起重电磁铁作业的馈电整流设备,又能作为起重作业现场的安全保障系统。在基于双向DC-DC变换器的电磁铁停电保磁系统中,本文为了提升双向DC-DC变换器的效率,提出一种基于线性控制的改进PWM移相控制策略,使变换器在宽电压和全负载范围内实现所有开关管零电压开关(Zero Voltage Switching,ZVS),且有效减小电感电流有效值,从而实现变换器整体效率的提升。实验结果表明,基于线性控制的改进PWM移相控制策略使双向DC-DC变换器的整体效率得到了提高,电磁铁停电保磁系统减少了设备体积,提高了可靠性,降低了能耗,提升了效率。
