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81.
火焰光度分析技术是一种能够快速灵敏检测硫、磷等元素的成熟方法。在环境检测,农残检测,工农业生产领域得到广泛应用。通过对传统火焰光度检测器的改进设计,采用光栅和CCD传感器阵列作为检测器的光电转换器件,拓展了检测化合物的种类,成功实现了对H2S,PH3,NH3,AsH3,Cl2为代表的硫、磷、氮、砷、氯五种元素的实时检测。由原来依靠特征波长检测拓展到利用物质火焰光度光谱信息进行定性定量分析。结合化学计量学的方法有望成为一种能够同时检测多类有毒有害气体的快速现场检测技术。 相似文献
82.
Western European freight forwarders are continually being forced to increase the efficiency of their transportation processes because of the liberalization and deregulation of the European transport market. This paper proposes a new real-time-oriented control approach in order to expand load consolidation, reduce empty vehicle trips, and handle dynamic disturbances. This approach integrates multimodal transportation and multiple transshipments for the first time. Thus, it enables the flexible generation and adaptation of transportation processes. In order to be able to handle occurring disturbances, an optimization procedure that adapts the transportation processes is continually applied. Vehicle breakdowns or deceleration of vehicles, traffic congestion, and street blockages are integrated as possible disturbance scenarios. At the same time, dynamically incoming transportation requests are also dealt with. Moreover, cooperative agreements between freight forwarders, which are gaining increasing importance, are integrated by mapping hubs and external services. The efficiency of the new real-time approach is validated by several computational experiments. In particular, the use of the entire execution time for plan adaptation as well as the integration of multiple transshipments has shown promising results. 相似文献
83.
测控数据实时监测软件是测控系统中的关键分系统之一,承担着大量测控信息的实时监视任务,由于其监测的数据具有信息量大、发送频率高、种类多样等特点,如何提升软件的性能和效率,成为了测控软件领域的一项重要课题。为实现该软件信息监测功能实时、全面、可靠,从软硬件平台、软件架构和算法设计等方面开展研究。采用多线程设计实现大量并行数据的接收,利用面向对象程序设计方法使数据处理层和展现层分离,对有曲线显示需求的数据存储方法进行了算法优化,从而实现软件的全面效能提升设计。设计的软件经实际环境测试,设计方法能够有效提升软件的效能,保证了测控数据监测功能的实时性和可靠性,增强了测控数据实时监测软件的数据承载能力。同时该方法设计的软件具有较好的可扩展性和可维护性。 相似文献
84.
85.
Qiang-Ling ZHANG Xue ZOU Qu LIANG Ya-Ting ZHANG Ming-Jian YI Hong-Mei WANG Chao-Qun HUANG Cheng-Yin SHEN Yan-Nan CHU 《分析化学》2018,46(4):471-478
Volatile organic compounds (VOCs) in ambient air can participate in photochemical reactions, which lead to the generation of secondary pollutants such as ozone and aerosol. So real-time and accurate monitoring of atmospheric VOCs plays an important role in the study of the causes of air pollution. On the basis of proton transfer reaction mass spectrometry (PTR-MS) research, a novel dipolar proton transfer reaction mass spectrometer (DP-PTR-MS) for real-time and on-line monitoring of atmospheric VOCs was developed. Compared with conventional PTR-MS with one kind of reagent ion H3O+, DP-PTR-MS had three kinds of reagent ions H3O+, OH?, (CH3)2COH+, which could be switched according to the actual detection need. So DP-PTR-MS can improve the qualitative ability and expand the detection range effectively. The reagent ion H3O+ can be used for detecting VOCs whose proton affinities are greater than that of H2O. The reagent ion OH? can be used to identify VOCs cooperating with the reagent ion H3O+, and can also be used for detecting some inorganic substances such as CO2. The reagent ion (CH3)2COH+ can be used for accurately detecting NH3 under interference elimination circumstances. The limit of detection (LOD) and sensitivity of DP-PTR-MS were measured by using six kinds of standard gases. The results showed that the LOD for detecting toluene was 7 × 10?12 (V/V) and the sensitivity for detecting ammonia reached 126 cps/10?9 (V/V). The ambient air in Hefei city was on-line and real-time monitored for continuous 78 h with DP-PTR-MS. The results showed that the newly developed DP-PTR-MS could be used for long-term and real-time monitoring atmospheric VOCs at the concentration of 10?12 (V/V) level. DP-PTR-MS is an important tool to the study of the causes of atmospheric pollution and the monitoring of trace VOCs emissions. 相似文献
86.
87.
通过定量检测大鼠去势前后肾上腺和前列腺中Cyp17a1基因的表达, 试图从分子水平解释去势手术后大鼠机体内雄性激素水平的变化. 相似文献
88.
介绍了一种针对单圈绝对式光电轴角编码器而设计的基于PCI总线的实时数据采集系统.该系统以PLX公司开发且服从PCI2.1协议的PCI9052为接口芯片,利用功能强大的CPLD作为控制单元.采用TI公司生产的高性能A/D器件ADS803E作为核心器件对线阵CCD输出的信号进行实时采集,并给出了板卡调试方法和如何用合适的驱动程序开发工具编写驱动程序.实验证明,该采集卡满足单圈绝对式光电轴角编码器数据采集的需要. 相似文献
89.
《Current Applied Physics》2019,19(12):1379-1382
Reduction of MoO3 in extreme reducing condition is a way to achieve Mo metal. However, effect of less extreme reductive-annealing, where it allows to keep the crystal structure, on physical and chemical properties of MoO3 has not been well-studied. In this work, we studied the evolution of Mo valence state during reductive annealing and its effect on high temperature transport. We found the formation of oxygen vacancies on surface of MoO3 single crystals at the low temperature, which is evidenced by increase of Mo5+ and color change. In addition, formation of Mo4+ was at the elevated temperature. For understanding the relation between bulk conductivity and Mo valence state, real-time impedance spectroscopy is employed. Use of two different gases makes it possible to distinguish impedance responses of MoO3 from those of reduced MoO3-x. Also, from time-dependent impedance measurements, we observed the evolution of transport behaviour by evolution of Mo valence state. 相似文献
90.
设计了一种含有8-oxoG碱基的新型分子信标, 结合酶促反应发展了一种非同位素标记的人8-oxoG-鸟嘌呤糖苷酶1(hOGG1)的活性分析新方法, 检出限可达0.0125 U/mL. 此外, 该方法还可用于快速考察金属离子对酶促反应的影响和肿瘤细胞中hOGG1活性水平的定量检测. 实验结果表明, 该方法简单、 灵敏, 有望用于肿瘤样品中hOGG1活性的高通量分析和hOGG1抑制剂的筛选. 相似文献