流动注射在线分离富集-火焰原子吸收光谱法测定环境水样中Cr(Ⅲ)和Cr(Ⅵ)的形态

采用单阀阴离子和阳离子交换树脂微柱并联 ,两柱交替采样逆向洗脱流动注射在线分离富集环境水样中Cr(Ⅲ )和Cr(Ⅵ ) ,分别用 15 %HNO3和 8%NH4 NO3洗脱 ,火焰原子吸收光谱法直接检测。富集 1min时Cr(Ⅲ )和Cr(Ⅵ )的特征浓度分别为 :1 5 0 μg·L- 1 和 1 39μg·L- 1 ,Cr(Ⅲ )和Cr(Ⅵ )检出限 (3σ)分别为 1 0 3μg·L- 1 和 0 5 4 μg·L- 1 ;相对标准偏差 (10 μg·L- 1 )分别为 :3 4 1%和 1 80 % ,分析样品加标回收率在 93 5 %～ 10 7 5 %之间。     

光纤光栅弹簧管压力传感器的压力和温度特性

本文利用弹簧管对于压力的机械放大作用,将弹簧管与光纤光栅悬臂梁调谐技术相结合,研制了一种新颖的光纤光栅弹簧管压力传感器,大大提高了光纤布喇格光栅对压力测量的灵敏度,压力灵敏度系数可达-1.79×10^-4/MPa,比裸光栅提高了两个数量级,在0～12MPa的压力范围内,光纤布喇格光栅中心反射波长的改变与压力成良好的线性关系.同时由于悬臂梁热膨胀效应的影响,光纤光栅的温度灵敏度提高为裸光栅的7倍.     

LIA组元的脉冲功率调制系统研制

本文介绍一种以加速组元为终端负载的纳秒脉冲功率系统。获得的加速间隙电压为350kV，90ns(半高宽)，波形上升时间为30ns；Blumlein主开关工作电压大于280kV，抖动小予1.5ns(均方根值)。对同轴场畸变开关性能的进一步改善作了必要的讨论，提出了用等场强原则偏置触发极，比通常采用自然中位面方法，可使开关工作电压提高8．7％。     

慢波介质自由电子激光器

本文采用一维流体模型导出了慢波介质自由电子激光器的线性色散方程,建立了电子和波相互作用的同向回旋同步机理和反向回旋同步机理.     

The Adsorption of NOx on Magnesium Aluminium Hydrotalcite

Magnesium aluminium hydrotalcite (Mg-Al-HT) with molar ratio of Mg-to-Al of 3 to 1 was prepared and characterized by X-ray diffraction (XRD) and infrared spectra (IR). The performances of Mg-Al-HT for the adsorption and desorption of NOx were studied. The results indicated that the adsorption capacity of the hydrotalcite for NOx was 1398.2mg/g, and it was higher than the acticarbon‘s. The adsorption capacities depended on adsorption time and temperature.Mg-Al-HT could be regenerated by thermal decomposition, and the adsorption efficiency had not changed markedly after three cycles.     

强磁场下Cernox^TM温度传感器的磁致电阻效应研究

以Cernox-1070温度传感器为研究对象,研究了其在磁场强度0-16 T和4.2-300K温区下的磁致电阻效应.实验结果表明：CX-1070温度传感器受磁场的影响较小,在16T、4.2-300K的磁效应值为-0.19-2.38%,产生的最大测量误差为0.11K;15-50K温区为磁效应最低的温度区间,在50-300...     

ZSM-5/Y复合分子筛在烃类催化裂化催化剂中的应用研究

以大庆减压蜡油为原料，考察了水热脱铝ZSM-5/Y复合分子筛的催化裂化性能，并与经同样条件水热脱铝的ZSM-5和Y型沸石的机械混合分子筛进行了对比研究。结果表明，与机械混合样品相比，复合分子筛具有较大的柴油产率和气体产率，汽油产率降低。从复合分子筛结构和ZSM-5的择形催化两方面分析了复合分子筛和机械混合分子筛裂化性能差别的原因。复合分子筛的聚集体结构不利于大分子进入分子筛结构中进行裂化，有利于汽油组分的裂化。气体数据分析支持了复合分子筛的结构特点。     

Characterization and separation of Al_(13) species using gel-filtration chromatography

Polyaluminum chloride (PAC) coagulant has been developed and widely used in water and wastewater treatment industry since the 1980s[1]. PAC is normally made by partial hydrolysis of acid aluminum chloride solution using slow alkaline titration method. However, this method would result in many different Al species. Among these Al species, it seems that tridecamer (Al13O4(OH) 724 , often denoted by Al13) is the most effective and stable polymeric Al species for water and wastewater treatme…     

Biodegradable amphiphilic block copolymers containing functionalized PEO blocks:Controlled synthesis and biomedical potentials

A series of controllable amphiphilic block copolymers composed of poly(ethylene oxide)(PEO) as the hydrophilic block and poly(ε-caprolactone)(PCL) as the hydrophobic block with the amino terminal group at the end of the PEO chain(PCL-b-PEO-NH2) were synthesized.Based on the further reaction of reactive amino groups,diblock copolymers with functional carboxyl groups(PCL-b-PEO-COOH) and functional compounds RGD(PCL-b-PEO-RGD) as well as the triblock copolymers with thermosensitive PNIPAAm blocks(PCL-b-PEO-b-P...     

多晶Hg0.09Cd0.91Te薄膜的光电化学行为

富镉Hg_(1-x)Cd_xTe是一种新型的光电转换材料,已用于固体结太阳能光伏电池:ITO/CdS/Hg_(1-)Cd_xTe/Au。我们曾对Hg_(1-x)Cd_xTe的电沉积机理作过研究。最近我们用电沉积制备的Hg_(0.09)Cd_(0.91)Te多晶薄膜做成了液体结太阳能光电化学电池并观察到明显光电响应。