scholarly journals Improvements in the profiles and distributions of nitric acid and nitrogen dioxide with the LIMS version 6 dataset

2010 ◽  
Vol 10 (10) ◽  
pp. 4741-4756 ◽  
Author(s):  
E. Remsberg ◽  
M. Natarajan ◽  
B. T. Marshall ◽  
L. L. Gordley ◽  
R. E. Thompson ◽  
...  
Keyword(s):  
Nitric Acid ◽  
Nitrogen Dioxide ◽  
Theoretical Calculations ◽  
Spin Splitting ◽  
Oxides Of Nitrogen ◽  
Polar Night ◽  
Chemical Effects ◽  
Satellite Sensors ◽  
Precision And Accuracy

Abstract. The quality of the Nimbus 7 Limb Infrared Monitor of the Stratosphere (LIMS) nitric acid (HNO3) and nitrogen dioxide (NO2) profiles and distributions of 1978/1979 are described after their processing with an updated, Version 6 (V6) algorithm and subsequent archival in 2002. Estimates of the precision and accuracy of both of those species are developed and provided herein. The character of the V6 HNO3 profiles is relatively unchanged from that of the earlier LIMS Version 5 (V5) profiles, except in the upper stratosphere where the interfering effects of CO2 are accounted for better with V6. The accuracy of the retrieved V6 NO2 is also significantly better in the middle and upper stratosphere, due to improvements in its spectral line parameters and in the reduced biases for the accompanying V6 temperature and water vapor profiles. As a result of these important updates, there is better agreement with theoretical calculations for profiles of the HNO3/NO2 ratio, day-to-night NO2 ratio, and with estimates of the production of NO2 in the mesosphere and its descent to the upper stratosphere during polar night. In particular, the findings for middle and upper stratospheric NO2 should also be more compatible with those obtained from more recent satellite sensors because the effects of the spin-splitting of the NO2 lines are accounted for now with the LIMS V6 algorithm. The improved precisions and more frequent retrievals of the LIMS profiles along their orbit tracks provide for better continuity and detail in map analyses of these two species on pressure surfaces. It is judged that the chemical effects of the oxides of nitrogen on ozone can be studied quantitatively throughout the stratosphere with the LIMS V6 data.

scholarly journals Improvements in the profiles and distributions of nitric acid and nitrogen dioxide with the LIMS version 6 dataset

2010 ◽  
Vol 10 (2) ◽  
pp. 2769-2808
Author(s):  
E. Remsberg ◽  
M. Natarajan ◽  
T. Marshall ◽  
L. L. Gordley ◽  
R. E. Thompson ◽  
...  
Keyword(s):  
Water Vapor ◽  
Nitric Acid ◽  
Nitrogen Dioxide ◽  
Theoretical Calculations ◽  
Oxides Of Nitrogen ◽  
Polar Night ◽  
Chemical Effects ◽  
Satellite Sensors ◽  
Precision And Accuracy

Abstract. The quality of the Nimbus 7 Limb Infrared Monitor of the Stratosphere (LIMS) nitric acid (HNO3) and nitrogen dioxide (NO2) profiles and distributions of 1978/1979 is described after their processing with an updated, Version 6 (V6) algorithm and subsequent archival in 2002. Estimates of the precision and accuracy of both of those species are developed and provided herein. The character of the V6 HNO3 profiles is relatively unchanged from that of the earlier LIMS Version 5 (V5) profiles, except in the upper stratosphere where the interfering effects of CO2 are accounted for better with V6. The accuracy of the retrieved V6 NO2 is also significantly better in the middle and upper stratosphere, due to improvements in its spectral line parameters and in the reduced biases for the accompanying V6 temperature and water vapor profiles. As a result of these important updates, there is better agreement with theoretical calculations for profiles of the HNO3/NO2 ratio, day-to-night NO2 ratio, and with estimates of the production of NO2 in the mesosphere and its descent to the upper stratosphere during polar night. The improved precisions and more frequent retrievals of the profiles along the LIMS orbit tracks provide for better continuity and detail in map analyses of these two species on pressure surfaces. It is judged that the chemical effects of the oxides of nitrogen on ozone can be examined quantitatively throughout the stratosphere with the LIMS V6 data, and that the findings will be more compatible with those obtained from measurements of the same species from subsequent satellite sensors.

scholarly journals A study of the chemical quality of ambient air at selected intersections in the Durban Metropolis

2003 ◽  
Author(s):  
◽  
Shalini Singh
Keyword(s):  
Nitric Oxide ◽  
Air Pollution ◽  
Nitrogen Dioxide ◽  
Ambient Air ◽  
Urban Environments ◽  
Motor Vehicles ◽  
Chemical Quality ◽  
Oxides Of Nitrogen ◽  
Combustion Processes

Motor vehicles are considered a major source of air pollution in urban environments. Nitrogen dioxide (N02) and nitric oxide (NO) which are collectively referred to as oxides of nitrogen (NOx) are formed at high temperatures during combustion processes in the engines of motor vehicles and are emitted via the exhaust into the atmosphere. Nitrogen dioxide is regarded as an irritant of the respiratory system.

Chemical Effects and Predictive Factors in Premature Birth

2018 ◽  
Vol 69 (7) ◽  
pp. 1796-1801
Author(s):  
Adrian Neacsu ◽  
Alina Calin ◽  
Anca Daniela Braila ◽  
Dan Navolan ◽  
Mihai Dimitriu ◽  
...  
Keyword(s):  
Extracellular Matrix ◽  
Premature Birth ◽  
Tissue Concentration ◽  
Premature Labor ◽  
New Born ◽  
Uterine Contractions ◽  
Chemical Effects ◽  
Equal Importance ◽  
Necrosis Factor

Premature birth is considered to be the consequence of independent alterations in the cervix and in the uterus. During labor, for full-term birth, as well as for premature birth, the cervix changes, from firm, long and closed, to soft and pliable, through a biochemical process characterized by the reshaping of the extracellular matrix and a growth of the tissue concentration of inflammatory mediators; the uterus proves an increase in contractility and sensitivity to endogenic hormones, such as oxytocin. Premature labor is associated with the premature activation of the release of cytokines in the decidua (mucosa lining uterus walls) and cervix. Interleukins IL-1 beta, IL-6, IL-8 and the alpha tumoral necrosis factor increase the production and activation of matrix metalloproteinases (MMP-1, MMP-3 and MMP-9) and of cathepsin S, which digests the collagen from the extracellular matrix of the cervix, causing the wiping and softening of the cervix. These cytokines are released by leukocytes in the myometer, leading to the production of prostaglandins and oxytocin, which stimulate uterine contractions. Therefore, the cervical shortening represented by ultrasound is believed to represent premature cervical softening. The obstetrical approach of aspects related to premature birth are based, considerably, on the prognosis expected by the obstetrician regarding the survival of the premature new-born baby, as well as the therapeutic variants to be followed. And not only survival is important, of equal importance is also the quality of life of underweight, immature new-born babies, who are considerably affected both physically, and intellectually.

scholarly journals Nonreciprocal charge transport up to room temperature in bulk Rashba semiconductor α-GeTe

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Yan Li ◽  
Yang Li ◽  
Peng Li ◽  
Bin Fang ◽  
Xu Yang ◽  
...  
Keyword(s):  
Charge Transport ◽  
Room Temperature ◽  
Theoretical Calculations ◽  
Ferromagnetic Layer ◽  
Spin Splitting ◽  
New Paradigm ◽  
Rashba Spin ◽  
Rashba Spin Splitting ◽  
Fundamental Insight ◽  
Insight Into

AbstractNonmagnetic Rashba systems with broken inversion symmetry are expected to exhibit nonreciprocal charge transport, a new paradigm of unidirectional magnetoresistance in the absence of ferromagnetic layer. So far, most work on nonreciprocal transport has been solely limited to cryogenic temperatures, which is a major obstacle for exploiting the room-temperature two-terminal devices based on such a nonreciprocal response. Here, we report a nonreciprocal charge transport behavior up to room temperature in semiconductor α-GeTe with coexisting the surface and bulk Rashba states. The combination of the band structure measurements and theoretical calculations strongly suggest that the nonreciprocal response is ascribed to the giant bulk Rashba spin splitting rather than the surface Rashba states. Remarkably, we find that the magnitude of the nonreciprocal response shows an unexpected non-monotonical dependence on temperature. The extended theoretical model based on the second-order spin–orbit coupled magnetotransport enables us to establish the correlation between the nonlinear magnetoresistance and the spin textures in the Rashba system. Our findings offer significant fundamental insight into the physics underlying the nonreciprocity and may pave a route for future rectification devices.

Volumetric and Phase Behavior of the Nitric Acid-Nitrogen Dioxide System

1954 ◽  
Vol 46 (12) ◽  
pp. 2541-2546 ◽  
Author(s):  
W. H. Corcoran ◽  
H. H. Reamer ◽  
B. H. Sage
Keyword(s):  
Nitric Acid ◽  
Nitrogen Dioxide ◽  
Phase Behavior

scholarly journals Impact of Diwali firework emissions on air quality of New Delhi, India during 2013-2015

MAUSAM ◽  
2021 ◽  
Vol 68 (1) ◽  
pp. 111-118
Author(s):  
SUNIL KUMAR PESHIN ◽  
PRIYANKA SINHA ◽  
AMIT BISHT
Keyword(s):  
Particulate Matter ◽  
Air Quality ◽  
Surface Ozone ◽  
Average Concentration ◽  
New Delhi ◽  
Oxides Of Nitrogen ◽  
Huge Amount ◽  
Awareness Campaigns ◽  
Pm10 And Pm2.5

Diwali is one of the major and most important festivals celebrated all over India which falls in the period late October to early November every year. It is associated with burning of firecrackers especially during the night of Diwali day that leads to degradation of air quality that lasts for a longer duration of time. Firecrackers on burning releases huge amount of trace gases such as NOx, CO, SO2 and O3 and huge amount of aerosols and particulate matter. The present study focuses on the influence of firecrackers  emissions on surface ozone(O3) ,oxides of nitrogen (NOx) and particulate matter (PM10 and PM2.5)concentration over the capital urban metropolis of India, New Delhi during Diwali festivity period from 2013-2015. A sharp increase is observed in surface ozone, NOx and particulate matter concentration during the Diwali day as compared to control day for 2013 to 2015 which is mainly attributed to burning of firecrackers. However the average concentration levels of the  gaseous pollutants and particulate matter (PM10 and PM2.5) on Diwali day exhibited a decline in 2015 and 2014 as compared to 2013 due to increase in  awareness campaigns among public and increased cost of firecrackers.  

scholarly journals Tissue Morphology and Antigenicity in Mouse and Rat Tibia: Comparing 12 Different Decalcification Conditions

2019 ◽  
Vol 67 (8) ◽  
pp. 545-561 ◽  
Author(s):  
Kristofor Bogoevski ◽  
Anna Woloszyk ◽  
Keith Blackwood ◽  
Maria A. Woodruff ◽  
Vaida Glatt
Keyword(s):  
Nitric Acid ◽  
Formic Acid ◽  
Ethylenediaminetetraacetic Acid ◽  
Research Question ◽  
Good Alternative ◽  
Clinical Applications ◽  
Tissue Morphology ◽  
Different Temperatures ◽  
Rat Tibia

Conventional bone decalcification is a time-consuming process and is therefore unsuitable for clinical applications and time-limited research projects. Consequently, we compared the effect of four different decalcification solutions applied at three different temperatures, and assessed the rate of decalcification and the implications on tissue morphology and antigenicity of mouse and rat tibiae. Bones were decalcified with 10% ethylenediaminetetraacetic acid (EDTA), 10% formic acid, 5% hydrochloric acid, and 5% nitric acid at 4C, 25C, and 37C. Decalcification in both species was fastest in nitric acid at 37C and slowest in EDTA at 4C. Histological and immunohistochemical staining confirmed that the conventional protocols of EDTA at 4C and 25C remain the best option regarding the quality of tissue preservation. Whereas formic acid at 4C is a good alternative saving about 90% of the decalcification time, hydrochloric and nitric acids should be avoided particularly in case of rat tibia. By contrast, due to their smaller size, mouse tibiae had shorter decalcification times and tolerated higher temperatures and exposure to acids much better. In conclusion, this study demonstrated that depending on the specific research question and sample size, alternative decalcification methods could be used to decrease the time of decalcification while maintaining histological accuracy.

Governmental perspectives on evaluating laboratory performance

1993 ◽  
Vol 39 (7) ◽  
pp. 1461-1467 ◽  
Author(s):  
D J Boone
Keyword(s):  
Medical Decision Making ◽  
Medical Decision ◽  
Diagnostic Efficiency ◽  
Regulatory Requirements ◽  
Misleading Information ◽  
Potential Patient ◽  
Precision And Accuracy ◽  
Total Testing Process ◽  
Test Result

Abstract The quality of laboratory analytical performance required to support medical decision-making has been defined in four major ways: (a) by the analytical variance of the state of the practice; (b) by the total variance, including analytical and biological variability; (c) by the loss of diagnostic efficiency attributable to analytical error; and (d) by medical-usefulness criteria. From the federal government's perspective, the answer to the question "How good must a laboratory test result be to be medically relevant?" must take into account the clinical context of the test, with accompanying concerns about access, timeliness, and cost, as well as limits for precision and accuracy in the analytical process and the frequency and potential patient-care impact of error in the pre- and postanalytical steps of the total testing process. Therefore, medically relevant goals should encompass not only analytical precision and accuracy but also goals to provide access to clinically effective tests and to reduce errors in the total testing process that can lead to medically misleading information. Development of more appropriate regulatory requirements for laboratories, as well as any needed improvements in instrumentation and methodology, should focus on ensuring that goals for medically relevant results are met by appropriate design and management of the entire process of laboratory testing.

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