Spectroscopic Evidence for Atmospheric Stabilization of Aluminum Borohydride in Polydimethylsiloxane Grease

2012 ◽  
Vol 66 (5) ◽  
pp. 591-594 ◽  
Author(s):  
Premkumar Sivasubramanian ◽  
Rana Mohtadi ◽  
Ragaiy Zidan ◽  
Kutty Pariyadath ◽  
Chad L. Leverette ◽  
...  
Keyword(s):  
Vibrational Spectroscopy ◽  
Room Temperature ◽  
Spectroscopic Evidence ◽  
Dry Air

Raman and infrared vibrational spectroscopy were used to confirm the presence of aluminum borohydride dissolved in a commercial polydimethylsiloxane vacuum grease at room temperature. Spectroscopic evidence for an adduct between the aluminum borohydride and polydimethylsiloxane is also presented. Once dissolved in the polydimethylsiloxane grease, the aluminum borohydride was stabilized with respect to its usual pyrophoric reactivity in wet or dry air.

Effect of Cold Working and Annealing on Oxidation Rates of Copper in Dry Air at Room Temperature

CORROSION ◽  
1968 ◽  
Vol 24 (12) ◽  
pp. 407-410 ◽  
Author(s):  
P. K. KRISHNAMOORTHY ◽  
S. C SIRCAR
Keyword(s):  
Room Temperature ◽  
Lattice Distortion ◽  
Cold Working ◽  
Oxide Films ◽  
Dry Air ◽  
Oxidation Rates ◽  
Substrate Metal ◽  
Thin Oxide Films ◽  
Thin Oxide ◽  
Kinetics Of

Abstract The effect of plastic deformation and further annealing on the kinetics of growth of thin oxide films on copper at 30 C (86 F) has been investigated. Oxidation rate was found to decrease markedly with increasing deformation. Further annealing showed an increase in the rate, the most pronounced changes occurring during the recrystallization stage. Results are interpreted in the light of Cabrera-Mott theory of growth of very thin oxide films on metals. The change in rate has been related to the concentration of cation vacancies in the Cu2O semi-conductor, which is dependent on the lattice distortion and defect concentration of the substrate metal.

scholarly journals The tribological properties of Al-brasses in various environments

2017 ◽  
Vol 61 (3) ◽  
pp. 91-94
Author(s):  
M. Lovíšek ◽  
T. Liptáková ◽  
J. Bronček ◽  
S. Dundeková
Keyword(s):  
Tribological Properties ◽  
Room Temperature ◽  
Tribological Behavior ◽  
Cold Drawing ◽  
Operating Conditions ◽  
Air Cooling ◽  
Normal Loading ◽  
Dry Air ◽  
Similar Chemical ◽  
Made In

Abstract Tribological properties of Al-brass pipes of various producers were studied in different environments. The tested brasses have very similar chemical composition, but they differ in microstructure due to mainly by heat treatment after cold drawing. Microstructure as well as roughness of surface influence chemical and mechanical properties which are important in operating conditions. The experiments of tribological behavior were made in various environments, dry air, cooling treated water and 3.5 % solution of NaCl at room temperature 21 ± 2°C. The tribological tests were carried out on the Linear Tribometer at normal loading 5 N by the method ball on plate for the duration of 5500 s. The measured friction coefficients were evaluated by the program DIAdem and the diagrams were created from signal generated by software NSignal Express

Spectroscopic evidence for a gas-phase librating G-quartet–Na+ complex

2014 ◽  
Vol 50 (94) ◽  
pp. 14767-14770 ◽  
Author(s):  
C. Fraschetti ◽  
M. Montagna ◽  
L. Guarcini ◽  
L. Guidoni ◽  
A. Filippi
Keyword(s):  
Gas Phase ◽  
Room Temperature ◽  
Spectroscopic Evidence

The Na+–G4 adduct exists as a mixture of two metastable populations, rapidly interconverting at room temperature.

scholarly journals P.1.30 Assessment of sick building syndrome among employees in the commercial centers in Niš, serbia

2019 ◽  
Vol 76 (Suppl 1) ◽  
pp. A85.2-A85
Author(s):  
Bojana Miladinovic ◽  
Maja Nikolic ◽  
Aleksandra Stankovic ◽  
Sci Visa Tasic
Keyword(s):  
Logistic Regression ◽  
Room Temperature ◽  
Ventilation System ◽  
Sick Building Syndrome ◽  
Binary Logistic Regression ◽  
Static Electricity ◽  
Cross Sectional ◽  
Quality Of Working Life ◽  
Dry Air ◽  
Sick Building

Sick Building Syndrome (SBS) is a diseases associated with indoor air quality accompanied with various nonspecific symptoms that occur in the occupants of a building. This syndrome has been the subject of serious scientific investigation in the past years, but there are not enough studies in transition countries.The aim of this study was to investigate the symptoms of the syndrome among employees in the commercial centers in Niš, Serbia.MethodsThe cross-sectional study was conducted amongst employees of two commercial centers in the city of Niš, Serbia. In this study the MM-040EA questionnaire was used with two additional questions and 1152 employed were interviewed during the period of three years. Data extracted from the questionnaires were analyzed using the chi-square test and binary logistic regression.ResultsThe prevalence of SBS was high. The most common symptoms reported by employees included high room temperature (74.9%), stuffy air (73.5%), and dry air (75.7%), while rare complaints were towards static electricity (47.3%) and low room temperature (45.2%). Binary logistic regression showed that too low room temperature (p=0.002), dry air (p=0.015), static electricity (p=0.007) and noise (p=0. 024) were the most important factors for the high symptoms score. A relatively small number of sick absence (13.4%) was found among subjects working in the investigated commercial centers.ConclusionThe high prevalence of SBS symptoms in the environment of commercial centers was almost associated with factors of unpleasant microclimate. So improvement of environmental conditions such as increasing the efficiency of the ventilation system, increasing fresh air flow in the sector and noise prevention , as well as enhancing the quality of working life will motivate the employees and increase productivity in the workplace. The occupational health care workers play an important role in educating of workers and their employers.

Laboratory Studies on the Behaviour of the Douglas-fir Beetle, Dendroctonus pseudotsugae Hopkins

1966 ◽  
Vol 98 (9) ◽  
pp. 953-991 ◽  
Author(s):  
M. D. Atkins
Keyword(s):  
Room Temperature ◽  
Douglas Fir ◽  
Single Source ◽  
Laboratory Studies ◽  
Population Changes ◽  
Dendroctonus Pseudotsugae ◽  
Dry Air ◽  
Light Gradient ◽  
Preferred Temperatures ◽  
Behavioural Types

AbstractThe behaviour of Dendroctonus pseudotsugae Hopk. in different physiological states was studied in relation to temperature, light, and host.Newly emerged beetles preferred temperatures near the threshold for flight. When conditioned in dry air at room temperature for 16 hours they preferred cooler temperatures.At room temperature, most newly emerged beetles settled in the brightest zone of a light gradient (55 foot-candles), although some settled in dimmer zones. If the beetles' emergence was delayed or if they were stored after emergence, more remained in the zone between 0.5 and 10 foot-candles.In light-dark tests at room temperature most newly emerged beetles were photopositive, but some were indifferent and a few were photonegative. Increasing the temperature and humidity increased the proportion of photonegative individuals. Newly emerged females oriented more directly to a single source of light than males, bur after conditioning or aging both reacted similarly.Females were separated into three behavioural types based on their reactions. Photopositive individuals flew more readily than indifferent or photonegative beetles; some photonegative females showed no inclination to fly.Photopositive females were usually host negative but photonegative females were host positive. The proportion of these behavioural types within different samples varied. A group that emerged early contained a higher incidence of photopositive host-negative individuals than a group that emerged late, or was stored for 10 days after emergence. But host-negative beetles would attack logs after starvation, flight exercise, or exposure to more attractive hosts.Host-positive females contained less fat than host-negative siblings. The decline in lipids during aging, starvation or flight thus may induce behavioural changes.There is a co-ordination of successive activities in the Douglas-fir beetle similar to that reported for aphids. The initial urge to disperse outweighs responses to host stimuli, but this balance changes as the beetles fly or as host stimuli increase. The balance between thresholds for dispersal and attack also varies in relation to the conditions under which the emerging beetles developed. Consequently, each individual behaves differently when it emerges. The behaviour of a population changes as the season progresses and from year to year owing to changes in the state of individuals and in the attractiveness of hosts.

scholarly journals Raman Spectroscopic Evidence of a Coherent Room Temperature Hybrid Structure of BaTiO3Single Crystal

2009 ◽  
Vol 116 (1) ◽  
pp. 68-71
Author(s):  
E. Liarokapis ◽  
A. Antonakos ◽  
A. Kojima ◽  
Y. Yoshimura
Keyword(s):  
Room Temperature ◽  
Hybrid Structure ◽  
Spectroscopic Evidence ◽  
Raman Spectroscopic

Interaction of sulfur dioxide and dry cold air in causing bronchoconstriction in asthmatic subjects

1984 ◽  
Vol 57 (2) ◽  
pp. 419-423 ◽  
Author(s):  
R. A. Bethel ◽  
D. Sheppard ◽  
J. Epstein ◽  
E. Tam ◽  
J. A. Nadel ◽  
...  
Keyword(s):  
Sulfur Dioxide ◽  
Room Temperature ◽  
Airway Resistance ◽  
Random Order ◽  
Gas Mixtures ◽  
Cold Air ◽  
Dry Air ◽  
Specific Airway Resistance ◽  
Blinded Study ◽  
Before And After

To determine whether sulfur dioxide and airway cooling and drying interact in causing bronchoconstriction in persons who have asthma, we measured specific airway resistance in seven asthmatic subjects before and after they performed voluntary eucapnic hyperpnea for 3 min breathing four different gas mixtures. The mixtures, which the subjects breathed through a mouthpiece in random order on 4 different days, were 1) humidified room-temperature air, 2) humidified room-temperature air containing 0.5 ppm SO2, 3) cold dry air, and 4) cold dry air containing 0.5 ppm SO2. Each subject breathed at a rate and depth known from preliminary studies to cause little or no bronchoconstriction when that subject inhaled 0.5 ppm SO2 in humidified room-temperature air or cold dry air. When given independently in the blinded study, 0.5 ppm SO2 or cold dry air again caused insignificant bronchoconstriction, but when given together the two stimuli caused significant bronchoconstriction, as indicated by an increase in specific airway resistance from 6.94 +/- 2.85 to 22.35 +/- 10.28 l X cmH2O X l–1 X s (mean +/- SD) (P less than 0.001). thus airway cooling and/or drying increases the bronchoconstriction induced by inhaled SO2 in persons who have asthma. This increase suggests that persons who have asthma may be more sensitive to the bronchoconstrictor effects of ambient SO2 in cold dry environments than in warm moist environments.

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