Full-size experimental assessment of the aerodynamic sealing of air curtains for particulate matter

Author(s):  
João Carlos Viegas ◽  
Pascal Kaluzny ◽  
Alexandra Durand ◽  
Lisa Fluchaire ◽  
Dulce Franco ◽  
...  

An air curtain is used to ensure an adequate separation between two compartments that is aimed to restrict, a clean one and a contaminated one. The air curtain performance is improved with the use of an air extraction from the “contaminated” compartment. The aerodynamic sealing of an optimized air curtain is assessed regarding particulate matter. The evaluation using visual assessment of the aerodynamic sealing using a cold smoke source is validated against PM 10 detection. It is shown that the air curtain presents a good aerodynamic sealing for the particulate of PM10 and PM2.5 classes and that the visual assessment method can lead to similar results. An equation was obtained with a view to be used to predict the level of aerodynamic sealing of the air curtain when the exhaust rate becomes too low. Another equation was obtained for predicting the average velocity through the door protected by the air curtain required to obtain an aerodynamic sealing, as a function of the jet parameters (nozzle average velocity and thickness). These test results prove that the air curtain, complemented with an air exhaust from the “contaminated compartment”, is suitable to provide an acceptable aerodynamic sealing for the particulate matter. Practical application: The findings of this research are applicable when it is necessary to retain the contamination due to particulate matter using a soft boundary, as air plane jets. This is applicable to medical care centres to reduce the possibility of contamination due to bacteria between different compartments or in pharmaceutical process units to avoid cross contamination among them.

2017 ◽  
Vol 39 (02) ◽  
pp. 133-140 ◽  
Author(s):  
Adriano Silva-Renno ◽  
Guilherme Baldivia ◽  
Manoel Oliveira-Junior ◽  
Maysa Brandao-Rangel ◽  
Elias El-Mafarjeh ◽  
...  

AbstractAir pollution is a growing problem worldwide, inducing and exacerbating several diseases. Among the several components of air pollutants, particulate matter (PM), especially thick (10–2.5 µm; PM 10) and thin (≤2.5 µm; PM 2.5), are breathable particles that easily can be deposited within the lungs, resulting in pulmonary and systemic inflammation. Although physical activity is strongly recommended, its effects when practiced in polluted environments are questionable. Therefore, the present study evaluated the pulmonary and systemic response of concomitant treadmill training with PM 2.5 and PM 10 exposure. Treadmill training inhibited PM 2.5- and PM 10-induced accumulation of total leukocytes (p<0.001), neutrophils (p<0.001), macrophages (p<0.001) and lymphocytes (p<0.001) in bronchoalveolar lavage (BAL), as well as the BAL levels of IL-1beta (p<0.001), CXCL1/KC (p<0.001) and TNF-alpha (p<0.001), whereas it increased IL-10 levels (p<0.05). Similar effects were observed on accumulation of polymorphonuclear (p<0.01) and mononuclear (p<0.01) cells in the lung parenchyma and in the peribronchial space. Treadmill training also inhibited PM 2.5- and PM 10-induced systemic inflammation, as observed in the number of total leukocytes (p<0.001) and in the plasma levels of IL-1beta (p<0.001), CXCL1/KC (p<0.001) and TNF-alpha (p<0.001), whereas it increased IL-10 levels (p<0.001). Treadmill training inhibits lung and systemic inflammation induced by particulate matter.


2021 ◽  
Vol 10 (2) ◽  
pp. 245
Author(s):  
Andrzej Sieśkiewicz ◽  
Tomasz Łysoń ◽  
Marek Rogowski ◽  
Marek Bielecki ◽  
Ewa Gindzienska-Sieskiewicz ◽  
...  

Purpose: The risk of epiphora after medial maxillectomy with lacrimal duct transection is difficult to assess. The data available in the literature are inconclusive due to various operating techniques used by the authors of medical publications, different additional procedures aimed at improving tear drainage after maxillectomy, and a variety of lacrimal duct patency assessment techniques. The aim of our work was to assess the anatomical and functional patency of lacrimal ducts after medial maxillectomy without performing additional procedures to improve tear drainage as well as comparison of the results obtained with different assessment tests. Materials and methods: 21 patients who underwent medial maxillectomy in the years 2016–2019 were assessed for discomfort and epiphora based on patients’ own reports and basic clinical examination, lacrimal duct rinse test, the Munk score, and a modified endoscopic Jones I test. Results: Gradually increasing the sensitivity of the assessment method resulted in an increase in the number of patients with potential tear drainage disorders, starting from 0% in the rinsing test, 4.8% self-reported tearing complaints, 14.3% Munk score, and 19% modified endoscopic Jones I test. Conclusions: The study results revealed that a small fraction of patients tend to report epiphora as a consequence of medial maxillectomy themselves. Subtle functional disorders, which are not particularly bothersome to patients, are more common. More sensitive lacrimal duct patency tests reveal more cases of tear drainage disorders. The results of studies assessing the incidence of epiphora after medial maxillectomy appear to depend on the type of test used.


2010 ◽  
Vol 11 (3) ◽  
pp. 210-214 ◽  
Author(s):  
Nicholas J. Souter ◽  
Shaun Cunningham ◽  
Stuart Little ◽  
Todd Wallace ◽  
Bernard McCarthy ◽  
...  

2015 ◽  
Vol 1096 ◽  
pp. 562-566 ◽  
Author(s):  
Bo Yu ◽  
Tao Hong ◽  
Jian Zhang ◽  
Qing Yu Liang

Due to the superior structure style, orthotropic steel bridge deck has been getting more and more widely practical application. The static and fatigue tests of the orthotropic steel bridge deck models were carried out in this research paper, which presented the fatigue damage developing laws, compared the test results with homogeneous test results in existing documents, and according to the relative fatigue accumulative damage theory, the fatigue accumulative damage equations of the sectional specimen and the whole specimen are respectively studied.


Plant Disease ◽  
1999 ◽  
Vol 83 (9) ◽  
pp. 799-805 ◽  
Author(s):  
H. Scherm ◽  
W. E. Copes

Blueberry fruit infected by Monilinia vaccinii-corymbosi (causal agent of mummy berry disease) are unfit for processing because of the formation of hardened structures (pseudosclerotia) within them. In commercial packinghouses in Georgia, fruit loads exceeding the tolerance level for mummy berry are appraised at lower quality grades, resulting in severe economic penalties to producers. Two methods to detect and enumerate mummy berry in blueberry loads were evaluated in the laboratory using fruit samples with known numbers of infected fruit. The first method involved destructive processing of the samples in a blender. The resulting blueberry puree was passed through a series of screens and the number of pseudosclerotia of M. vaccinii-corymbosi retained on the screens assessed tactilely. The second method consisted of visual symptom assessment of intact fruit. Bias and coefficients of variation of the blender method in five experiments ranged from -63.0 to 152.4% and 6.9 to 44.1%, respectively, indicating that the method was inaccurate and imprecise. Several factors probably contributed to its poor performance, including the formation of multiple fragments from single pseudosclerotia during blending and subjectivity in the tactile assessment of pseudosclerotia. Bias and coefficients of variation of the visual assessment method in four experiments ranged from -3.41 to 1.97% and 1.16 to 5.17%, respectively. Thus, the visual method was considerably more accurate and more precise than the blender method. Visual assessment was further evaluated under commercial packinghouse conditions, with >70,000 fruit assessed individually for symptoms of mummy berry and other abnormalities. Bias ranged from -11.1 to 33.3%, indicating that visual assessment was less accurate under packinghouse conditions than under laboratory conditions. This was due to the low number of infected fruit encountered in most of the loads, which resulted in large relative errors if only a single fruit was misidentified. In a two-year packinghouse survey, a high incidence of partial infection, together with successional variations in discoloration of infected portions of the fruit as the harvest season progressed, resulted in a greater variation of mummy berry symptoms than previously described.


Author(s):  
A. Berezniak ◽  
Т. Dudnik ◽  
O. Zakutko

The summarized results of special tests of the Mi-2MSB helicopter equipped with the experimental system of 12,7 mm small arms (as a part with series-produced machine guns NSVT-12,7) and the serial system of unguided missile armament (NAR type C-8) are presented. The actual volume of assessments of inspections and work performed during the tests is given. According to the results of processing the test materials, it was determined that the tactical range of the Mi-2MSB helicopter with the installed weapons system and boxes for collecting spent units (in the design provided for testing) at a takeoff mass of 3700 kg, at an altitude of not more than 300 m during combat mission in the area of the target for 5 minutes and the remaining fuel on the landing of 100 liters is (not less): version of combat equipment 2 × B8V8MSB (payload - 16 NAR) - 190 km; version of combat equipment 2 × NSVT-12.7 (payload - 600 rounds) - 200 km; version of combat equipment 2 × B8V8MSB + 2 × NSVT-12.7 (payload - 16 NAR and 600 rounds) - 155 The results of special tests practically showed that the Mi-2MSB helicopter, equipped with an aviation weapon system, in addition to the functional tasks defined for the basic Mi-2MSB helicopter, is able to provide: training and maintenance of skills for flight crew in the practical application of unguided aviation weapons and gun armaments in all types of maneuvering, defined by the tactics of army aviation; accomplishment of certain tasks on air support of columns of troops on the march and fire missions on destruction of enemy manpower, single unarmored and lightly armored targets such as car, armored personnel carrier, infantry fighting vehicle, boat, The main combat and functional capabilities in the actual operating conditions confirmed by the results of special tests as well as their validation of specified requirements make it possible (after eliminating the shortcomings identified in the test), to allow operation of Mi-2MSB helicopter in the entire operating range of heights and speeds equipped with aircraft weapons as part of the unguided missile system (NAR type C-8) and small arms system (as part of the series-produced machine guns NSVT-12.7)).


Author(s):  
Ramin Nabizadeh ◽  
Mostafa Hadei

Introduction: The wide range of studies on air pollution requires accurate and reliable datasets. However, due to many reasons, the measured concentra-tions may be incomplete or biased. The development of an easy-to-use and reproducible exposure assessment method is required for researchers. There-fore, in this article, we describe and present a series of codes written in R Programming Language for data handling, validating and averaging of PM10, PM2.5, and O3 datasets.   Findings: These codes can be used in any types of air pollution studies that seek for PM and ozone concentrations that are indicator of real concentra-tions. We used and combined criteria from several guidelines proposed by US EPA and APHEKOM project to obtain an acceptable methodology. Separate   .csv files for PM 10, PM 2.5 and O3 should be prepared as input file. After the file was imported to the R Programming software, first, negative and zero values of concentrations within all the dataset will be removed. Then, only monitors will be selected that have at least 75% of hourly concentrations. Then, 24-h averages and daily maximum of 8-h moving averages will be calculated for PM and ozone, respectively. For output, the codes create two different sets of data. One contains the hourly concentrations of the interest pollutant (PM10, PM2.5, or O3) in valid stations and their average at city level. Another is the   final 24-h averages of city for PM10 and PM2.5 or the final daily maximum 8-h averages of city for O3. Conclusion: These validated codes use a reliable and valid methodology, and eliminate the possibility of wrong or mistaken data handling and averaging. The use of these codes are free and without any limitation, only after the cita-tion to this article.


2011 ◽  
Vol 201-203 ◽  
pp. 643-646 ◽  
Author(s):  
Bo Yan Xu ◽  
Hai Ying Tian ◽  
Jie Yang ◽  
De Zhi Sun ◽  
Shao Li Cai

SNCR (Selective Non Catalytic Reduction) system is proposed, with 40% methylamine aqueous solution as reducing agent to reduce NOx in diesel exhaust gas. The effect of injection position and volume on the reduction efficiency through the test bench is systematically researched. A three-dimensional model of a full-sized diesel SNCR system generated by CFD software FIRE is used to investigate the reduction efficiency under different temperatures. The simulated results have a good agreement with the test results, and it can be used to optimize SNCR system. The results can indicate the practical application of this technology.


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