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91.
This paper reviews literature information on the behaviour of semivolatile organic compounds (SVOCs) in the indoor environment,
as well as the most likely emission sources. The consecutive stages of analytical procedures used for monitoring SVOCs in
indoor environments are described. The most common approaches used for collecting samples from the gas and particulate phases
are mentioned. The paper discusses and compares various types of sorbents and filters applied in dynamic, passive and denudational
techniques, as well as the techniques used to liberate the SVOCs, including Soxhlet, sonication and microwave extraction.
The main advantages and disadvantages of each technique are discussed, together with possible future trends. The approaches
commonly used during the final determination step, such as gas chromatography and liquid chromatography, are presented together
with their possible drawbacks, and ways of eliminating them are suggested. The review makes brief reference to the effects
of human exposure to SVOCs in house dust and discusses the main aspects of the analytical procedures used to monitor the presence
of SVOCs in this medium. 相似文献
92.
利用可再生清洁能源将CO2转化为CO和其他小分子是合成含碳燃料的可观方法之一.间歇性可再生能源存储的重要策略之一是将二氧化碳进行电化学还原.选择具有高活性和稳定性的电催化剂对于电化学还原CO2至关重要.在这项研究中,我们使用简单的电沉积方法合成了具有纳米晶枝状结构的CuAu合金电极.各项表征显示原子比约为1∶1的CuA... 相似文献
93.
Jacek Lipok Tomasz Cierpicki Paweł Kafarski 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6-7):1657-1660
Alternaria sp. isolated from the surface of carrot ( Daucus carota ) seeds appeared to be able to degrade amino-(4-methoxyphenyl)-methanephosphonic acid using it as a sole source of carbon, nitrogen, and phosphorus for growth. 相似文献
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97.
Vladislav S. Olkhovsky Vittoria Petrillo Jacek Jakiel Wiesław Kantor 《Central European Journal of Physics》2008,6(1):122-127
The particle tunneling through a 3-D rectangular potential barrier has been studied. The simplest model for multiple internal
reflections has been assumed. The explicit expression for all the transmission and reflection probability amplitudes have
been derived, as well as the tunneling and reflection phase times.
相似文献
98.
Frydrychowski AF Gumiński W Rojewski M Kaczmarek J Juzwa W 《IEEE transactions on bio-medical engineering》2002,49(8):887-904
This paper presents technical foundations for a new technique of near-infrared transillumination-backscattering sounding, which is designed to enable noninvasive detection and monitoring of changes in the width of the subarachnoid space (SAS) and magnitude of cerebrovascular pulsation in humans. The key novelty of the technique is elimination of influence of blood flow in the scalp on the signals received from two infrared sensors-proximal and distal. A dedicated digital algorithm is used to estimate on line the ratio of the powers of received signals, referred to as two-sensor distal-to-proximal received power quotient, TQ (t). The propagation duct for NIR radiation reaching the distal sensor is the SAS filled with translucent cerebrospinal fluid. Information on slow fluctuations of the average width of the SAS is contained in the slow-variable part of the TQ (t), called the subcardiac component, and in TQ itself. Variations in frequency and magnitude of faster oscillations of the width of that space around the baseline value, dependent on cerebrovascular pulsation, are reflected in instantaneous frequency and envelope of the fast-variable component. Frequency and magnitude of the cerebrovascular pulsation depend on the action of the heart, so this fast-variable component is referred to as the cardiac component. 相似文献
99.
Jacek Tabor 《Journal of Differential Equations》2002,180(1):171-197
100.
Jacek Cichon Andrzej Jasinski Anastasis Kamburelis Przemyslaw Szczepaniak 《Proceedings of the American Mathematical Society》2002,130(6):1833-1842
In this paper we discuss various questions connected with translations of subsets of the real line. Most of these questions originate from W. Sierpinski. We discuss the number of translations a single subset of the reals may have. Later we discuss almost invariant subsets of Abelian groups.