scholarly journals A heat and moisture mask attenuates cardiovascular stress during cold air exposure

2013 ◽  
Vol 7 (3) ◽  
pp. 123-129 ◽  
Author(s):  
John Seifert ◽  
Megan McNair ◽  
Patricia DeClercq ◽  
John St Cyr
Keyword(s):  
Air Exposure ◽  
Cold Air ◽  
Cardiovascular Stress ◽  
Heat And Moisture

1199 GLYCEROL HYPERHYDRATION REDUCES THE DIURESIS INDUCED BY WATER ALONE DURING COLD AIR EXPOSURE

1994 ◽  
Vol 26 (Supplement) ◽  
pp. S213
Author(s):  
B. J. Freund ◽  
J. M. McKay ◽  
D. E. Roberts ◽  
J. E. Laird ◽  
C. O??Brien ◽  
...  
Keyword(s):  
Air Exposure ◽  
Cold Air

Technology of Heat and Moisture Regeneration for Ventilation Systems

2021 ◽  
pp. 174-222
Keyword(s):  
Silica Gel ◽  
Air Temperature ◽  
Sodium Acetate ◽  
Temperature Drop ◽  
Sodium Sulphate ◽  
Efficiency Factor ◽  
Cold Air ◽  
Temperature Efficiency ◽  
Heat And Moisture ◽  
Ventilation Systems

The chapter is focused on technology of heat and moisture regeneration for ventilation systems. In the first sub-division recent progress in adsorptive technologies for air dehumidification, heating and conditioning is analyzed. In the next sub-divisions results of original researches of authors on adsorptive heat and moisture regeneration are given. The design of adsorptive heat-moisture regenerator for ventilation systems is shown. Its operation and the results of field tests are described. The technology of regeneration of low-potential heat and moisture by composite sorbent ‘silica gel – sodium sulphate' is suggested. Experimental plots of temperature, absolute and relative humidity at the inlet and the outlet of the apparatus and between cassettes with the composite are given. Correlation of flows switch-over time, airflow rate and temperature drop is stated. The relationships temperature efficiency factor vs. dimensionless temperature drop and moisture efficiency factor vs. absolute humidity dimensionless drop are derived with fair accuracy for engineering calculation. Ability of purposeful modification of the above-mentioned characteristics within broad ranges by changing the half-cycle time, the size of the granules of the adsorbent and its amount is revealed. The mathematical model and algorithm for determining the basic parameters of adsorptive regenerator operating processes are developed. The proposed algorithm involves calculating the volume of air passed through the layer of adsorptive heat-storage material, the concentration of water in the airflow at the outlet of the regenerator, the adsorption, the heat of adsorption, the final temperature of the cold air, the air temperature after mixing the cold air from the street and the warm air in the room at the warm end of the regenerator during inflow, calculation of the final concentration of water in the flow at the cold end of the regenerator, the volume of air passing through the layer of heat-accumulating material, adsorption and heat of adsorption, the final temperature of the air at the cold end of the regenerator, the air temperature after mixing of the cold air from the street and the warm air from the room at the cold end of regenerator during outflow, determining the temperature efficiency coefficient, summarized adsorption and maximal adsorption time. The correlation of air temperatures near the warm and cold end of the regenerator, as well as the temperature efficiency factors calculated according to the proposed algorithm and obtained by experimental way is confirmed. The mathematical modeling of the processes of operation of adsorption regenerators based on composites ‘silica gel – sodium sulphate' and ‘sodium acetate' in the conditions of the typical ventilation system of residential premises is carried out. The dependences of the temperature efficiency factor vs. the time of switching air flows and the velocity of air flow, as well as the temperatures of external and internal air under stationary conditions are shown. An optimal composition of composite adsorbents is stated to be 20% of silica gel and 80% of salt, that is, sodium sulphate or sodium acetate. Due to higher value of maximal adsorption composite ‘silica gel – Na2SO4' is shown to be required in half as much as compared with ‘silica gel – CH3COONa'. The results of the research can be used in the development of energy-efficient ventilation systems and devices for residential and warehouse premises.

scholarly journals Effects of a heat and moisture exchanger on respiratory function and symptoms post–cold air exercise

2019 ◽  
Vol 30 (3) ◽  
pp. 591-601 ◽  
Author(s):  
Clemens Frischhut ◽  
Michael D. Kennedy ◽  
Martin Niedermeier ◽  
Martin Faulhaber
Keyword(s):  
Respiratory Function ◽  
Heat And Moisture Exchanger ◽  
Moisture Exchanger ◽  
Cold Air ◽  
Heat And Moisture

Shivering onset, metabolic response, and convective heat transfer during cold air exposure

1991 ◽  
Vol 70 (5) ◽  
pp. 1996-2002 ◽  
Author(s):  
P. Tikuisis ◽  
D. G. Bell ◽  
I. Jacobs
Keyword(s):  
Heat Transfer ◽  
Metabolic Rate ◽  
Body Fat ◽  
Convective Heat ◽  
Heat Fluxes ◽  
Air Exposure ◽  
Cold Air ◽  
Convective Heat Loss ◽  
Norm Group ◽  
Lean Group

The onset and intensity of shivering of various muscles during cold air exposure are quantified and related to increases in metabolic rate and convective heat loss. Thirteen male subjects resting in a supine position and wearing only shorts were exposed to 10 degrees C air (42% relative humidity and less than 0.4 m/s airflow) for 2 h. Measurements included surface electromyogram recordings at six muscle sites representing the trunk and limb regions of one side of the body, temperatures and heat fluxes at the same contralateral sites, and metabolic rate. The subjects were grouped according to lean (LEAN, n = 6) and average body fat (NORM, n = 7) content. While the rectal temperatures fluctuated slightly but not significantly during exposure, the skin temperature decreased greatly, more at the limb sites than at the trunk sites. Muscles of the trunk region began to shiver sooner and at a higher intensity than those of the limbs. The intensity of shivering and its increase over time of exposure were consistent with the increase in the convective heat transfer coefficient calculated from skin temperatures and heat fluxes. Both the onset of shivering and the magnitude of the increase in metabolic rate due to shivering were higher for the LEAN group than for the NORM group. A regression analysis indicates that, for a given decrease in mean skin temperature, the increase in metabolic rate due to shivering is attenuated by the square root of percent body fat. Thus the LEAN group shivered at higher intensity, resulting in higher increases in metabolic heat production and convective heat loss during cold air exposure than did the NORM group.

scholarly journals The combined effects of silicon dioxide nanoparticles and cold air exposure on the metabolism and inflammatory responses in white adipocytes

2017 ◽  
Vol 6 (5) ◽  
pp. 705-710
Author(s):  
Yongqiang Zhang ◽  
Xi Li ◽  
Yangsheng Lin ◽  
Li Zhang ◽  
Zhan Guo ◽  
...  
Keyword(s):  
Air Pollution ◽  
Silicon Dioxide ◽  
Inflammatory Responses ◽  
Potential Hazard ◽  
Combined Effects ◽  
Silicon Dioxide Nanoparticles ◽  
Air Exposure ◽  
Cold Air ◽  
White Adipocytes

The potential hazard of nanoparticles (NPs) from air pollution has attracted widespread attention.

GENDER EFFECT OF A COLD-AIR EXPOSURE 773

1997 ◽  
Vol 29 (Supplement) ◽  
pp. 134
Author(s):  
J. E. Reading ◽  
D. E. Roberts ◽  
J. A. Hodgdon
Keyword(s):  
Gender Effect ◽  
Air Exposure ◽  
Cold Air

A breathing filter exchanging heat and moisture prevents asthma induced by cold air

Allergy ◽  
1995 ◽  
Vol 50 (3) ◽  
pp. 225-228 ◽  
Author(s):  
E Millqvist ◽  
B Bake ◽  
U Bengtsson ◽  
O. Löwhagen
Keyword(s):  
Cold Air ◽  
Heat And Moisture

scholarly journals PERFORMANCE CHARACTERISTICS OF ADSORPTIVE REGENERATOR OF LOW-POTENTIAL HEAT AND MOISTURE BASED ON COMPOSITE ADSORBENTS ‘SILICA GEL – SODIUM SULPHATE’ SYNTHESIZED BY SOL – GEL METHOD

2018 ◽  
Vol 82 (1) ◽  
Author(s):  
Олена Анатолівна Бєляновська ◽  
Роман Дмитрович Литовченко ◽  
Костянтин Михайлович Сухий ◽  
Михайло Порфирович Сухий ◽  
Михайло Володимирович Губинський
Keyword(s):  
Silica Gel ◽  
Air Temperature ◽  
Sodium Sulfate ◽  
Sol Gel ◽  
Efficiency Coefficient ◽  
Final Temperature ◽  
Cold Air ◽  
Gel Method ◽  
Temperature Efficiency ◽  
Heat And Moisture

Досліджені експлуатаційні характеристики адсорбційного регенератора низько-потенційного тепла та вологи на основі композитних сорбентів «силікагель – натрій сульфат», синтезованих золь – гель методом. Розроблені математична модель та алгоритм визначення базових параметрів процесів експлуатації адсорбційного регенератора в умовах сектора житлово-комунального господарства.  Запропонований алгоритм включає розрахунок об’єму повітря, який пройшов через шар теплоакумулюючого матеріалу, концентрації води в повiтрi на виході з теплового акумулятора, адсорбції, теплоти адсорбції, кінцевої  температури холодного повітря, температури повітря після змішування холодного повітря з вулиці та теплого повітря в приміщенні при подачi, розрахунок концентрації води в повiтрi на виході з теплового акумулятора, об’єму повітря, який пройшов через шар теплоакумулюючого матеріалу, адсорбції та теплоти адсорбції, кінцевої температури теплого повітря, температури повітря після змішування холодного повітря з вулиці та теплого повітря з приміщення при викиді, визначення температурного коефіцієнта корисної дії, сумарної адсорбції та часу досягнення максимальної адсорбції. Підтверджена кореляція температур повітря біля теплого та холодного кінці регенератора, а також теплових коефіцієнтів корисної дії, встановлених за результатами розрахунків згідно запропонованого алгоритму та дослідним шляхом. Проведено математичне моделювання процесів експлуатації адсорбційних регенераторів на основі композитів «силікагель – натрій сульфат» в умовах типової системи вентиляції житлових приміщень. Показана залежність теплового коефіцієнта корисної дії від часу перемикання потоків повітря, швидкості руху потоків повітря, а також температур зовнішнього та внутрішнього повітря в стаціонарних умовах. Максимальні значення теплових коефіцієнтів корисної дії встановлені при швидкості вологого повітря близько 0,22 –  0,32 м/с та часу перемикання потоків 5 – 10 хв.. Виявлено вплив швидкості руху потоків вологого повітря на час досягнення максимальної адсорбції. Результати проведеного дослідження можуть бути використані при розробці енергоефективних вентиляційних систем та пристроїв для житлових та складських приміщень. The performance characteristics of the adsorptive  regenerator of the low-potential heat and moisture on basis of the composite sorbents ‘silica gel - sodium sulfate’ synthesized by sol-gel method are studied. The mathematical model and algorithm for determining the basic parameters of adsorptive regenerator exploitive processes in the housing and communal services sector are developed. The proposed algorithm includes calculating the volume of air passed through the layer of heat-accumulating material, the concentration of water in the flow at the exit from the regenerator, the adsorption, the heat of adsorption, the final temperature of the cold air, the air temperature after mixing the cold air from the street and the warm air in the room at the warm end of the regenerator during inflow, calculation of the final concentration of water in the flow at the cold end of the regenerator, the volume of air passing through the layer of heat-accumulating material, adsorption and heat of adsorption, the final temperature of the air at the cold end of the regenerator, the air temperature after mixing of  the cold air from the street and the warm air from the room at the cold end of regenerator during outflow, determining the temperature efficiency coefficient, summarized adsorption and maximal adsorption time. The correlation of air temperatures near the warm and cold end of the regenerator, as well as the thermal efficiency coefficients stated by the results of calculations according to the proposed algorithm and experimental way is confirmed. The mathematical modeling of the processes of operation of adsorption regenerators on the basis of ‘silica gel - sodium sulfate’ composites in the conditions of the typical ventilation system of residential premises is carried out. The dependences of the temperature efficiency coefficient vs. the time of switching air flows and the velocity of air flow, as well as the temperatures of external and internal air under stationary conditions are shown. The results of the research can be used in the development of energy-efficient ventilation systems and devices for residential and warehouse premises

scholarly journals Anaphylaxis Caused by Swimming: A Case Report of Cold-induced Urticaria in the Emergency Department

2021 ◽  
Vol 5 (3) ◽  
pp. 307-311
Author(s):  
Nicholas McManus ◽  
Robert Zehrung ◽  
Trevor Armstrong ◽  
Ryan Offman
Keyword(s):  
Emergency Department ◽  
Case Report ◽  
Cold Exposure ◽  
Disease Entity ◽  
Air Exposure ◽  
Cold Air ◽  
Physical Urticaria

Introduction: Cold-induced urticaria is a subset of physical urticaria that presents as wheals or angioedema in response to cold exposure. While most cases are idiopathic, secondary associations with infections, medications, and certain cancers have been described. Case Report: We discuss the case of a 50-year-old male with recent episodes of urticaria from cold air exposure following a flu-like illness six months prior, who presented with symptoms of anaphylaxis upon jumping into a lake. Conclusion: While the majority of patients develop localized symptoms, understanding this disease entity is imperative as up to one-third of patients can develop severe symptoms including anaphylaxis, particularly from water submersion during activities such as swimming.

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