Facility Air Leakage | ScienceGate

AbstractTo study the adsorption characteristics of CO, CO2, N2, O2, and their binary-components in lignite coal, reveal the influence of CO2 or N2 injection and air leakage on the desorption of CO in goafs, a lignite model (C206H206N2O44) was established, and the supercell structure was optimized under temperatures of 288.15–318.15 K for molecular simulation. Based on molecular dynamics, the Grand Canonical Monte Carlo method was used to simulate the adsorption characteristics and the Langmuir equation was used to fit the adsorption isotherms of gases. The results show that for single-components, the order of adsorption capacity is CO2 > CO > O2 > N2. For binary-components, the competitive adsorption capacities of CO2 and CO are approximate. In the low-pressure zone, the competitive adsorption capacity of CO2 is stronger than that of CO, and the CO is stronger than N2 or O2. From the simulation, it can be seen that CO2, N2 or O2 will occupy adsorption sites, causing CO desorption. Therefore, to prevent the desorption of the original CO in the goaf, it is not suitable to use CO2 or N2 injection for fire prevention, and the air leakage at the working faces need to be controlled.

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Size selection of the Ambu AuraOnce laryngeal mask in Chinese men weighing >70 kg: a pilot study

Journal of International Medical Research ◽

10.1177/03000605211016689 ◽

2021 ◽

Vol 49 (5) ◽

pp. 030006052110166

Author(s):

Jiahui Chen ◽

Chunhuan Chen ◽

Wei Xu ◽

Xiaoguang Zhang

Keyword(s):

Computed Tomography ◽

Success Rate ◽

Fiberoptic Bronchoscopy ◽

Laryngeal Mask ◽

Insertion Time ◽

Air Leakage ◽

Chinese Men ◽

Laryngeal Mask Insertion ◽

Laryngeal Anatomy ◽

Rate Requirement

Objective To collect computed tomography data of the laryngeal anatomy of Chinese men and to determine the feasibility of using the size 4 Ambu AuraOnce laryngeal mask (Ambu A/S, Copenhagen, Denmark) in Chinese men weighing >70 kg. Methods This prospective study involved men who underwent surgery from May 2018 to January 2019 at Jinshan Hospital. Pharyngeal and laryngeal parameters were measured by computed tomography. The laryngeal mask insertion success rate, requirement for tracheal tube insertion, laryngeal mask insertion time, fiberoptic bronchoscopy grading, air leakage pressure, and pharyngeal complications were analyzed. Results In a comparison of the size 4 and 5 Ambu AuraOnce devices, the first insertion success rate was 100% and 87% and the three-times insertion success rate was 100% and 93%, respectively, with no significant differences. However, the insertion time was significantly different at 19.6 ± 5.9 versus 31.1 ± 11.2 s, respectively, and the proportions of fiberoptic grading levels were also significantly different. There were no significant differences in the air leakage pressure or pharyngeal complications. Conclusion The size 4 Ambu AuraOnce is more adequate than the size 5 for Chinese men weighing >70 kg, with a shorter insertion time and higher fiberoptic bronchoscopic grading.

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Must attic ventilation be preserved in energy retrofits?

International Journal of Building Pathology and Adaptation ◽

10.1108/ijbpa-08-2018-0072 ◽

2019 ◽

Vol 37 (4) ◽

pp. 461-472

Author(s):

William Rose

Keyword(s):

Vapor Pressure ◽

Energy Efficient ◽

Design Methodology ◽

Air Leakage ◽

Content Type ◽

Buoyancy Flow ◽

Spreadsheet Model ◽

Radiation Exchange ◽

Moisture Performance ◽

Ashrae Standards

Purpose The addition of thermal insulation into attics along with air-tightening of the ceiling plane is a common first step in making homes more energy efficient. Attic ventilation was introduced decades ago on the assumption that air leakage across the ceiling was inevitable and not correctible – this was before the era of spray-applied foams. Often attic ventilation is provided at roof eaves, and ensuring good insulation in their location is critical to avoid cold corners in the rooms below. So may vents be blocked in the course of energy retrofits? The paper aims to discuss this issue. Design/methodology/approach This study consists of a simple spreadsheet model of attic performance. The model is built using material from ASHRAE Handbook Fundamentals and ASHRAE Standards. It includes: Glaser calculations for temperature, vapor pressure and vapor pressure excess; radiation exchange – solar and sky; buoyancy flow assumption for leakage from indoors; wind flow assumption for leakage from outdoors; and change in attic air RH as assumed indicator of change in sheathing moisture performance. Findings The model results show that lowered moisture contributions across air-tightened ceilings may compensate effectively for added insulation (which lowers the attic air temperature) and reduced moisture dilution from attic ventilation. Originality/value These results provide support for the policy of allowing attic ventilation reductions that are proportionate to ceiling air leakage reductions as part of weatherization efforts. Given the limitations of the model, continued field observations remain critical.

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Specifics of Building Envelope Air Leakage Problems and Airtightness Measurements

MATEC Web of Conferences ◽

10.1051/matecconf/20167302020 ◽

2016 ◽

Vol 73 ◽

pp. 02020 ◽

Cited By ~ 2

Author(s):

Anatolijs Borodinecs ◽

Jekaterina Nazarova ◽

Aleksandrs Zajacs ◽

Alexandr Malyshev ◽

Vladimir Pronin

Keyword(s):

Building Envelope ◽

Air Leakage

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Technique for combined application of fibrin sealant and bioabsorbable felt against alveolar air leakage

European Journal of Cardio-Thoracic Surgery ◽

10.1016/j.ejcts.2008.06.002 ◽

2008 ◽

Vol 34 (3) ◽

pp. 705-705 ◽

Cited By ~ 1

Author(s):

Tamami Isaka ◽

Masato Kanzaki ◽

Takamasa Onuki

Keyword(s):

Fibrin Sealant ◽

Air Leakage ◽

Alveolar Air ◽

Combined Application

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Air Leakage, Moisture Migration, and Condensation in a Building Enclosure

Forensic Engineering 2015 ◽

10.1061/9780784479711.005 ◽

2015 ◽

Cited By ~ 1

Author(s):

J. S. Der Ananian ◽

S. M. O’Brien ◽

C. M. Saldanha

Keyword(s):

Air Leakage ◽

Moisture Migration ◽

Building Enclosure

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Spontaneous otogenic pneumocephalus presenting with occipital subcutaneous emphysema as primary symptom: could tension gas cause the destruction of cranial bones?

Journal of Neurosurgery ◽

10.3171/2011.6.jns11104 ◽

2011 ◽

Vol 115 (4) ◽

pp. 679-683 ◽

Cited By ~ 4

Author(s):

Ninghui Zhao ◽

Doris D. Wang ◽

Xiaobin Huang ◽

Surya K. Karri ◽

Haiying Wu ◽

...

Keyword(s):

Minimally Invasive ◽

Subcutaneous Emphysema ◽

Air Pressure ◽

Air Leakage ◽

Mechanical Compression ◽

Tension Pneumocephalus ◽

First Case ◽

Subcutaneous Space

The authors report, to the best of their knowledge, the first case of a spontaneous tension pneumocephalus with subcutaneous emphysema. Hyperpneumatization of the cranium and mechanical compression contributed jointly to the formation of a fistula, and air pressure caused a subsequent disruption of the suture and air leakage into the subcutaneous space. A minimally invasive otological procedure proved efficacious for resolution.

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