氢同位素气体质谱分析进展

Analysis of hydrogen isotopes with MS (mass spectrometry) was reviewed, inclusive of history and actuality, principle and attaching. Some questions of the method of analysis of hydrogen isotopes with MS were pointed out as well.     

热表面电离质谱法测量钚同位素

The plutonium isotopic abundance ratio was analyzed by thermal ionization mass spectrometry (TIMS) with the ion counting technique. The ion counting system was developed and applied by our lab teem on the MAT261. It is verified with the certificated isotopic reference material. Using 3×10^－9 g of plutonium, the combined standard uncertainty of ratio of ²⁴⁰Pu to ²³⁹Pu plutonium isotopes in 3 ng is 0.070%.     

西藏雪莲花挥发油的GC/MS分析

The essential oils from Saussurea tridactyla were extracted by steam distillation. The chemical components of the essential oils were analyzed by GC/MS, and 23 compounds were identified, which account for 90% of the total essential oils.     

高炉非金属冷却壁耐火基体的工艺改进

郑州华宇集团和北京科技大学联合研制生产的非金属冷却壁是高炉冷却壁的发展方向,但其浇注耐火基体在工艺和性能等方面还有待全面优化。本文通过试验,从养护制度和分散剂的选用两个方面提出了切实可行的优化方案,提高了非金属冷却壁浇注耐火基体的综合性能。     

金属橡胶隔振器抗冲击性能研究

对金属橡胶隔振器的冲击性能进行了理论和实验研究。借助于金属橡胶构件的加载曲线和迟滞回线,研究了具有非线性干摩擦阻尼隔冲系统在短冲击和长冲击时的最大响应的计算方法,并借助于Matlab实现了最大冲击响应的逐步积分计算。通过实验研究了构件结构形状和参数、负载质量、冲击加速度等对金属橡胶构件抗冲击性能的影响,对理论方法进行了验证,为工程实践提供了依据。     

基于动态信道预约的自适应QoS切换算法

未来无线网络将为固定和移动用户提供多媒体通信和计算业务．为移动用户提供无线多媒体业务的一个最关键的挑战是保证端到端连接的业务质量．通过重复使用无线频谱的微蜂窝或微微蜂窝结构是一个有前途的改善移动多媒体网络容量的方式．但切换次数随着蜂窝大小的降低而增加．移动多媒体网络的一个至关重要的问题是需要可以满足各种QoS需要且有更高资源利用率的有效切换方式．该文提出了一种称为基于动态信道预约的自适应QoS切换算法,并与其它切换方式进行了性能比较．     

一种适用于OFDM-TDMA系统的载波频率偏移估计算法

该文提出了一种适用于OFDM-TDMA系统的载波频率偏移盲估计算法,它利用OFDM载波信道间内在的正交性,寻找与最小估计均方误差相对应的频偏来校正系统的频率偏移．通过计算机仿真表明,这种算法在频率选择性衰落信道下具有高的估计精度,且适用于时变环境下的频偏跟踪．     

微机电数字地震检波器设计及误差标定补偿方法

研制一种新型数字硅MEMS地震检波器，集成三支硅MEMS陀螺与加速度计，可提供三维加速度、速度、角速度及位移等振动信息，可提高检波器的信息量及效率；提出的基于无需指北单轴速率转台的硅MEMS地震检波器六位置正反速率标定方法，不仅可提高标定精度与效率，且可减小标定工作量。并经实验验证该数字硅MEMS地震检波器样机及标定补偿方法的可行性与适用性。     

同位素稀释-液相/气相-电感耦合等离子体质谱联用等方法为鱼肉中甲基汞成分标准物质准确定值

The fish tissue certified reference material is designed and prepared mainly for evaluating the determining accuracy of methyl mercury in sea fish or other seafood, as well as for a quality control standard. The property value was certified by three different methods, including high performance liquid chromatographic -cold vapor atomic fluorescence spectrometry（HPLC-CVAFS）method and species specific isotope dilution mass spectrometric analysis (IDMS) using an inductively coupled plasma mass spectrometer as detector after liquid chromatography (LC-ICP-MS) or gas chromatography (GC-ICP-MS). The experiment included spiking, extraction, derivatization, separation and detection procedures. The ERM 464 tuna fish reference material was used as the analytical quality control standard. The results obtained from three different methods were in good agreement. And the statistic average values were used as certified values of methylmercury in the fish tissue CRM.     

沙钢650万t钢板工程“一罐到底”的设计及生产

沙钢650万t钢板系统工程,由3座2 500 m3高炉和3座180 t转炉等生产工艺线组成。设计了“一罐到底”的工艺,即把高炉出铁场的铁水罐与到炼钢转炉兑铁水的铁水罐合二为一,取消了炼铁区域的铁水罐修理设施,没有二次倒罐环节,减少了倒罐作业,避免因倒罐引起的铁水温降和环境污染。经过4年的生产实践,取得了较为理想的生产效益和社会效益。