Michael-Addition Reaction of Malononitrile with a,β-Unsaturated Cycloketones Catalyzed by KF/Al_2O_3

The utility of fluoride salts as potential base in a va-riety of synthetic reactions has been recognized in re-cent years.1 However, low solubility of fluoride salts in ordinary solvents hampers their wide applications in organic synthesis. On the other hand, there has been increasing use of inorganic solid supports as catalysts for many years2 resulting in higher selectivity, milder reaction conditions and easier work-up. Especially po-tassium fluoride-coated alumina (KF-alumina) has been a …     

聚氯乙烯(PVC)膜固相光度法测定废水中汞

采用一种新型的、高灵敏度且简便易行的聚氯乙烯(PVC)膜固相光度法测定废水中汞含量。此方法基于Hg2+与Br-生成络阴离子HgBr-3,再与碱性染料罗丹明B(RB+)大阳离子形成有色缔合物(RB+·HgBr-3)。此缔合物被PVC膜吸附、富集后,于560nm波长下测定膜的吸光度。此方法线性范围为0.05～1.0μg·ml-1,检出限为0.01μg·ml-1,相对标准偏差小于5%。     

精确搜索下的非线性共轭梯度法

该文提出一种无约束优化非线性共轭梯度法，证明了精确线性 搜索下的全局收敛性。当目标函数为一致凸函数时，证明了算法具有线性收敛速度。数值实验表明算法对于求解实际问题是有效的。     

基于小波包分析及支持向量机的超音速目标识别方法研究

提出了基于小波包分析及支持向量机的超音速目标识别方法 .通过 5 .5 6mm ,7.6 2mm和 12 .7mm三种枪弹试验获取信号 ,用小波包分解激波信号 ,统计每个频带的能量特征 ,用支持向量机方法训练测试样本 ,获得了很好的分类效果 .仿真结果表明基于超音速飞行体产生的激波信号来识别目标是可行的 .     

Fenton 试剂处理2,4-D废水研究

利用Fenton试剂(Fe2+/H2O2)处理含有除草剂2,4-二氯苯氧乙酸(2,4-D)的模拟废水.结果显示,Fenton试剂对2,4-D有很好的去除效果.Fe2+和H2O2的摩尔比为1:20,在H2O2为1/2Qth理论投加量的条件下处理30mtn,2,4-D去除率达到80.0%.考察了Fe2+投加量、Fe2+和H2O2投加比、2,4-D初始浓度和pH等因素对2,4-D降解的影响.通过GC-MS和HPLC检测到反应中间产物有2,4-二氯苯酚、邻氯苯酚和对氯苯酚,氯离子在这些中间产物上释放.通过离子色谱检测到进一步氧化的产物还有小分子酸,如乙醇酸、乙醛酸、顺丁烯二酸,提出了Fenton降解2,4 -D的可能途径.     

Photocatalytic Synthesis of Oxygenates from Gaseous CO2 and CH4 over Semiconductor

Photoinduced synthesis of CO2 and CH4 was investigated using a batch reaction system on several photoactive materials supported on silicon dioxide. Single semiconductor showed higher selectivity to C1 compounds. The production of C2-C3 oxygenates took place preferentially on composite semiconductor photocatalysts. In particular, it was found that acetone was the primary product over Cu/CdS-TiO2/SiO2.     

全变差有界函数列的一致(R)可积性

给出了一致有界单调函数列一致可积性定理 ,由此得出全变差序列有界的收敛函数列的一致可积性 .说明了该结论可判断一些非一致收敛函数列的逐项积分性质 .     

Hα Emission Imaging during Supersonic Molecular Beam Injection by CCD Photograph

There are several fuelling methods for tokamak plasma： pellet injection （PI）, gas puffing （GP）, neutral beam injection （NBI） and supersonic molecular beam injection （SMBI） .SMBI has been created in the Southwestern Institute of Physics, China.     

Tokamak Experiment and Tokamak Engineering——Development of the Plasma Diagnostics on HL-2A Tokamak

The main mission the HL-2A tokamak is of the experiments on to explore the divertor physics and to investigate the plasma confinement, transport and instabilities with high power auxiliary heating and advanced fuelling, it is necessary to develop more new diagnostics and increase the spatial and temporal resolutions of the measurements for exist system. Up to now, about 30 diagnostic systems have been moved from HL-1M to HL-2A tokamak. Other 10 diagnostic systems are being designed and installed on the device. In developed in last 2 years, will be presented.     

Calculation of the Safety Factor of the Ohmic HL-2A Single Null Divertor Discharge

The safety most important factor profile is one of the the plasma discharge. For limiter configuration, people usually use the following cylindrical approximation formula to calculate it q（r）=5r^2BT/RIp where r is the minor radius of the plasma toms, R is the major radius （in m） , BT is the toroidal magnetic field （in T）, Ip is the total toroidal current（in MA）.