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Tamara Schad Natalie Preisig Wiebke Drenckhan Cosima Stubenrauch 《Journal of surfactants and detergents》2022,25(3):377-385
Liquid foams of intermediate stability have been shown to be very efficient in the cleaning of sensitive surfaces because of the synergy between imbibition and foam decay. While we quantified these mechanisms for contaminations with liquid oils in our previous work, we show here their extension to oils containing soot particles in an effort to simulate increasingly realistic contaminations. Using foams with a wide range of liquid fractions and with different stabilities, we show that the main cleaning mechanisms remain very similar, with the oil entraining the soot particles. However, we find much less efficient soot removal when the liquid channels of the foams are small enough to hinder efficient transport of the soot particles. 相似文献
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Carla C. B. Brasil Cristiano R. de Menezes Eduardo Jacob-Lopes Juliano Smanioto Barin Leila Queiroz Zepka Paulo Cezar Bastianello Campagnol Roger Wagner Alexandre José Cichoski 《International Journal of Food Science & Technology》2020,55(3):1136-1144
This study investigated the effect of the combination of basic electrolysed water (BEW) and slightly acid electrolysed water (SAEW) with ultrasound (US) for cleaning and sanitation of the knives used in slaughtering processes. The knives were sonicated in a US bath using two modes of operation (normal and sweep) in two steps: (i) 5 min with BEW and (ii) 10 min with SAEW at 35 °C. The microbiological counts and the possible changes in the physical structure of the knives were evaluated. The association BEW + SAEW + US, in the sweep mode, provided lower mesophilic, enterobacterial, Staphylococcus aureus and yeast counts when compared to the values recommended by the international legislation. In addition, these conditions removed all organic residues from the knife blades and promoted the highest migration rate of the residues to the US water bath (12.35 mg/L·min), without modifications in the knife blades. Thus, cleaning and sanitation of knives was feasible with the association of BEW + SAEW + US, which could be a useful alternative for the meat industry. 相似文献
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Kasper Kristensen David M. Lunderberg Yingjun Liu Pawel K. Misztal Yilin Tian Caleb Arata William W Nazaroff Allen H. Goldstein 《Indoor air》2019,29(4):645-655
Semivolatile organic compounds (SVOCs) emitted from building materials, consumer products, and occupant activities alter the composition of air in residences where people spend most of their time. Exposures to specific SVOCs potentially pose risks to human health. However, little is known about the chemical complexity, total burden, and dynamic behavior of SVOCs in residential environments. Furthermore, little is known about the influence of human occupancy on the emissions and fates of SVOCs in residential air. Here, we present the first‐ever hourly measurements of airborne SVOCs in a residence during normal occupancy. We employ state‐of‐the‐art semivolatile thermal‐desorption aerosol gas chromatography (SV‐TAG). Indoor air is shown consistently to contain much higher levels of SVOCs than outdoors, in terms of both abundance and chemical complexity. Time‐series data are characterized by temperature‐dependent elevated background levels for a broad suite of chemicals, underlining the importance of continuous emissions from static indoor sources. Substantial increases in SVOC concentrations were associated with episodic occupant activities, especially cooking and cleaning. The number of occupants within the residence showed little influence on the total airborne SVOC concentration. Enhanced ventilation was effective in reducing SVOCs in indoor air, but only temporarily; SVOCs recovered to previous levels within hours. 相似文献
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Alap Ali ZAHID Syed Raza ur REHMAN S. RUSHD Anwarul HASAN Mohammad Azizur RAHMAN 《Frontiers in Energy》2020,14(3):635
Imaging with high definition video camera is an important technique to visualize the drilling conditions and to study the physics of complex multiphase flow associated with the hole cleaning process. The main advantage of visualizing multiphase flow in a drilling annulus is that the viewer can easily distinguish fluid phases, flow patterns and thicknesses of cutting beds. In this paper the hole cleaning process which involves the transportation of cuttings through a horizontal annulus was studied. The two-phase (solid-liquid) and the three-phase (solid-liquid-gas) flow conditions involved in this kind of annular transportation were experimentally simulated and images were taken using a high definition camera. Analyzing the captured images, a number of important parameters like velocities of different phases, heights of solid beds and sizes of gas bubbles were determined. Two different techniques based on an image analysis software and MATLAB coding were used for the determinations. The results were compared to validate the image analyzing methodology. The visualization technique developed in this paper has a direct application in investigating the critical conditions required for efficient hole cleaning as well as in optimizing the mud program during both planning and operational phases of drilling. Particularly, it would be useful in predicting the cuttings transport performance, estimating solid bed height, gas bubble size, and mean velocities of bubbles/particles. 相似文献
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在烟气制酸,废酸废水处理系统工序中,pH 电极的在线应用较为广泛。为了满足工艺条件的需求 ,经常会对 pH 值进行连续在线监测及控制。由于生产现场的特殊工况 , 电极的检测球泡浸在被测溶液中,经常会发生结垢的现象 ;导致测量数据的失真或无法获取检测值 , 这种现象是电极使用中的常见现象同时也是 PH 电极在实际使用中的瓶颈问题。本文针对电极检测中出现的问题进行了详尽的分析、论证、汇总,提出了相应的解决办法及改进优化措施。 相似文献
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Touching contaminated surfaces might lead to the spread of pathogens, that is, the fomite transmission route. Although hand- and surface-hygiene practices are potentially important non-pharmaceutical interventions for the fomite route, the two interventions have been mostly studied separately in the literature. In this study, we develop a new conceptual model based on the law of mass action, analyze the temporal diffusion of contaminated surfaces and hands, and verify the model with simulations in an assumed norovirus outbreak in a buffet restaurant. A quantitative hygiene criterion is developed for the required frequency of surface disinfection and hand hygiene to control the fomite transmission in indoor environments. To eliminate surface contaminations, the product of pathogen-removal rates (including hygiene and natural death) on hands and surfaces must be no smaller than that of the human hand and surface contact frequency (ie, the net removal product must be non-negative). When the net removal product is negative, the number of contaminated surfaces and hands would show a logistic growth trend and finally approach the equilibrium. Our approach sheds light into how to optimize the combined use of hand hygiene and environmental decontamination for the best effectiveness under different settings. 相似文献