scholarly journals Carbon Dioxide Level in Neonatal Incubator: A Comparative Study of Two Baby Air Flow Input Methods in Incubator Chamber

2021 ◽  
Vol 5 (1) ◽  
pp. p65
Author(s):  
R. Vardanjans ◽  
L. Cirule

Preterm neonates often have to spend a long time in incubator which simulates necessary enviromental conditions to maintain patients in stable condition. Authors have found neglected problem with Carbon Dioxide (CO2) concentration in newborn inhaled gas when using “oxygen hood” into infant incubator that has not been studied very closely. Methods in this experiement were carried out as condition monitoring while changing some parameters and positions. Results have shown that CO2 level is letally high in some aspects. Situation is alarming as CO2 level in incubator is not limited by current regulation, as IEC60601-2-19: 2009 +A1:2016. Currently the Incubator manufacturers declare that CO2 maximal concentration should be periodically checked by users, which are hospitals. Some commercially available incubators have the maximum allowed CO2 level 8000 ppm, which is much higher than recommended 2000 ppm CO2 level in indoor working place. There is no limitation of maximal level of CO2 using “oxygen hood”, which are specified in incubator operation manual. This paper goal is to show the correlation of CO2 level versus gas flow into oxygen hood.

Author(s):  
Malcolm Brinn ◽  
Said F. Al-Sarawi ◽  
Tien-Fu Lu ◽  
Brian J. C. Freeman ◽  
Jaliya Kumaratilake ◽  
...  

Here, we present a staged approach for an innovative repurposing of a portable infant humidicrib into a live cell growth, observation, and imaging system. Furthmore, humidicrib can support different variations of “umbilical” bioreactors, and can be used to conduct electrophysiology experiments and in situ immunohistochemistry. Modifications incorporate a closed loop carbon dioxide (CO2) concentration control system with umbilical CO2 and heating support for tailored bioreactors. The repurposing cost is inexpensive and allows for the continued observation and imaging of cells. This prototype unit has been used to continuously observe and image live primary neurons for up to 21 days. This demonstrates the repurposed units’ suitability for use in tissue culture based research, particularly where modifications to microscopes are required or where sensitive manipulation outside of a standard incubator is needed.


2021 ◽  
pp. 68-71
Author(s):  
Igor M. Ageev ◽  
Yuri M. Rybin

The advantages and disadvantages of infrared and electrochemical gas analyzers for carbon dioxide CO2 are described. The possibility of using conductometric sensors with distilled water for monitoring the CO2 content in the air has been investigated. Two identical measuring systems were manufactured, each containing two open-type conductometric cells, a matching device and a personal computer. With the help of these complexes, experiments were carried out on the simultaneous measurement of the CO2 content in the air in two places (a laboratory room and a building in a forest, located at a distance of 15 km from each other) with deliberately different daily dynamics of the CO2 level change. A special experiment was carried out, which made it possible to obtain an estimate of the inertia of conductometric cells and a conversion factor for the values of CO2 content into standard units of measurement. It is shown that the daily dynamics of changes in the electrical conductivity of distilled water in open cells corresponds to the expected dynamics of changes in the CO2 content in the rooms where the measurements were carried out. The operability of the measuring complex and the possibility of creating on its basis a device for long-term monitoring of the CO2 content in the air mixture of gases has been confirmed. The principal high selectivity of the measuring complex to CO2 in relation to other gases of the atmosphere has been established.


2019 ◽  
Author(s):  
Kamau Wright ◽  
Robert Galvez

Abstract Simulations and experiments are conducted to model, simulate, test and demonstrate the effect of plasma discharges on decomposition of carbon dioxide (CO2). A pin-to-plane discharge is employed in gas samples containing CO2. A high voltage plasma system is used which was previously shown to be able to decrease CO2 concentration in gas samples. The discharge is modeled and described, including monitoring electrical parameters such as current and voltage. The present study investigated plasma decomposition of carbon dioxide experimentally, and through simulation. A plasma micro-discharge was utilized to better understand plasma-CO2 interactions. Enhancements are suggested to help increase the efficiency and yield of the plasma-CO2 decomposition process. Gas samples are analyzed over time using a CO2 meter.


2017 ◽  
Vol 10 (2) ◽  
pp. 667-680 ◽  
Author(s):  
Shohei Nomura ◽  
Hitoshi Mukai ◽  
Yukio Terao ◽  
Toshinobu Machida ◽  
Yukihiro Nojiri

Abstract. We developed a battery-powered carbon dioxide (CO2) measurement system for monitoring at the summit of Mt. Fuji (3776 m a.s.l.), which experiences very low temperatures (below −20 °C) and severe environmental conditions without access to gridded electricity for 10 months (from September to June). Our measurement system used 100 batteries to run the measurement unit during these months. These batteries were charged during the 2-month summer season when gridded electricity was available, using a specially designed automatic battery-charging system. We installed this system in summer 2009 at the Mt. Fuji weather station; observations of atmospheric CO2 concentration were taken through December 2015. Measurements were never interrupted by a lack of battery power except for two cases in which lightning damaged a control board. Thus we obtained CO2 data during about 94 % of the 6-year period. Analytical performances (stability and accuracy) were better than 0.1 ppm, as tested by checking working standards and comparisons with flask sampling.Observational results showed that CO2 mole fractions at Mt. Fuji demonstrated clear seasonal variation. The trend and the variability of the CO2 growth rate observed at Mt. Fuji were very similar to those of the Mauna Loa Observatory (MLO). Seasonally, the concentration at Mt. Fuji was 2–10 ppm lower in summer and 2–12 ppm higher in winter than those at MLO. The lower concentrations at Mt. Fuji in summer are mainly attributed to episodes of air mass transport from Siberia or China, where CO2 is taken up by the terrestrial biosphere. On the other hand, the relatively higher concentrations in winter seem to reflect the high percentage of air masses originating from China or Southeast Asia during this period, which carry increased anthropogenic carbon dioxide. These results show that Mt. Fuji is not very influenced by local sources but rather by the sources and sinks over a very large region.Thus we conclude that, as this system could provide stable measurement data with relatively easy operation for 6 years at Mt. Fuji, it could be a useful monitoring technique for remote background sites elsewhere.


Processes ◽  
2020 ◽  
Vol 8 (11) ◽  
pp. 1373
Author(s):  
Amir Izzuddin Adnan ◽  
Mei Yin Ong ◽  
Saifuddin Nomanbhay ◽  
Pau Loke Show

Carbon dioxide is the most influential gas in greenhouse gasses and its amount in the atmosphere reached 412 µmol/mol in August 2020, which increased rapidly, by 48%, from preindustrial levels. A brand-new chemical industry, namely organic chemistry and catalysis science, must be developed with carbon dioxide (CO2) as the source of carbon. Nowadays, many techniques are available for controlling and removing carbon dioxide in different chemical processes. Since the utilization of CO2 as feedstock for a chemical commodity is of relevance today, this study will focus on how to increase CO2 solubility in culture media used for growing microbes. In this work, the CO2 solubility in a different medium was investigated. Sodium hydroxide (NaOH) and monoethanolamine (MEA) were added to the culture media (3.0 g/L dipotassium phosphate (K2HPO4), 0.2 g/L magnesium chloride (MgCl2), 0.2 g/L calcium chloride (CaCl2), and 1.0 g/L sodium chloride (NaCl)) for growing microbes in order to observe the difference in CO2 solubility. Factors of temperature and pressure were also studied. The determination of CO2 concentration in the solution was measured by gas analyzer. The result obtained from optimization revealed a maximum CO2 concentration of 19.029 mol/L in the culture media with MEA, at a pressure of 136.728 kPa, operating at 20.483 °C.


2016 ◽  
Vol 56 (1) ◽  
pp. 108 ◽  
Author(s):  
Mei Bai ◽  
David W. T. Griffith ◽  
Frances A. Phillips ◽  
Travis Naylor ◽  
Stephanie K. Muir ◽  
...  

Accurate measurements of methane (CH4) emissions from feedlot cattle are required for verifying greenhouse gas (GHG) accounting and mitigation strategies. We investigate a new method for estimating CH4 emissions by examining the correlation between CH4 and carbon dioxide (CO2) concentrations from two beef cattle feedlots in Australia representing southern temperate and northern subtropical locations. Concentrations of CH4 and CO2 were measured at the two feedlots during summer and winter, using open-path Fourier transform infrared spectroscopy. There was a strong correlation for the concentrations above background of CH4 and CO2 with concentration ratios of 0.008 to 0.044 ppm/ppm (R2 >0.90). The CH4/CO2 concentration ratio varied with animal diet and ambient temperature. The CH4/CO2 concentration ratio provides an alternative method to estimate CH4 emissions from feedlots when combined with CO2 production derived from metabolisable energy or heat production.


2017 ◽  
Vol 68 (9) ◽  
pp. 1585 ◽  
Author(s):  
Stephen R. Midway ◽  
Caleb T. Hasler ◽  
Tyler Wagner ◽  
Cory D. Suski

Carbon dioxide (CO2) in fresh-water environments is poorly understood, yet in marine environments CO2 can affect fish behaviour, including predator–prey relationships. To examine changes in predator success in elevated CO2, we experimented with predatory Micropterus salmoides and Pimephales promelas prey. We used a two-factor fully crossed experimental design; one factor was 4-day (acclimation) CO2 concentration and the second factor CO2 concentration during 20-min predation experiments. Both factors had three treatment levels, including ambient partial pressure of CO2 (pCO2; 0–1000 μatm), low pCO2 (4000–5000 μatm) and high pCO2 (8000–10000 μatm). Micropterus salmoides was exposed to both factors, whereas P. promelas was not exposed to the acclimation factor. In total, 83 of the 96P. promelas were consumed (n=96 trials) and we saw no discernible effect of CO2 on predator success or time to predation. Failed strikes and time between failed strikes were too infrequent to model. Compared with marine systems, our findings are unique in that we not only saw no changes in prey capture success with increasing CO2, but we also used CO2 treatments that were substantially higher than those in past experiments. Our work demonstrated a pronounced resiliency of freshwater predators to elevated CO2 exposure, and a starting point for future work in this area.


Sensors ◽  
2021 ◽  
Vol 21 (19) ◽  
pp. 6436
Author(s):  
Mai Hu ◽  
Bing Chen ◽  
Lu Yao ◽  
Chenguang Yang ◽  
Xiang Chen ◽  
...  

Research on carbon dioxide (CO2) geological and biogeochemical cycles in the ocean is important to support the geoscience study. Continuous in-situ measurement of dissolved CO2 is critically needed. However, the time and spatial resolution are being restricted due to the challenges of very high submarine pressure and quite low efficiency in water-gas separation, which, therefore, are emerging the main barriers to deep sea investigation. We develop a fiber-integrated sensor based on cavity ring-down spectroscopy for in-situ CO2 measurement. Furthermore, a fast concentration retrieval model using exponential fit is proposed at non-equilibrium condition. The in-situ dissolved CO2 measurement achieves 10 times faster than conventional methods, where an equilibrium condition is needed. As a proof of principle, near-coast in-situ CO2 measurement was implemented in Sanya City, Haina, China, obtaining an effective dissolved CO2 concentration of ~950 ppm. The experimental results prove the feasibly for fast dissolved gas measurement, which would benefit the ocean investigation with more detailed scientific data.


2018 ◽  
Vol 12 (4) ◽  
pp. 4088-4097
Author(s):  
S. Ma’mun ◽  
Hallvard F. Svendsen ◽  
I. M. Bendiyasa

Global emission of carbon dioxide (CO2), a major contributor to the climate change, has increased annually and it reached over 37 Gt in 2017. An effort to reduce the emission, therefore, needs to be conducted, e.g. post-combustion capture by use of amine-based absorption. The objective of this study is to evaluate the kinetic and mass transfer parameters in a CO2 absorption process using monoethanolamine (MEA), 2-(methylamino)ethanol (MMEA), and 2-(ethylamino)ethanol (EMEA) as absorbents. The experiments were conducted in a bubble reactor at atmospheric pressure and 40 °C with 10-vol% CO2 flowrate of 5 NL/men. The CO2 concentration leaving the reactor was measured by an IR CO2 analyzer. The results obtained from this experiment were the overall absorption rates consisting of both chemical reaction and mass transfer. Analysis result shows that the reaction between CO2 and amines takes place fast, therefore the mass transfer of CO2 from the gas into the liquid through the gas film would control the overall absorption rate.


2011 ◽  
Vol 62 (10) ◽  
pp. 883 ◽  
Author(s):  
Mahabubur Mollah ◽  
Debra Partington ◽  
Genn Fitzgerald

Carbon dioxide (CO2) is the most important greenhouse gas, predicted to increase globally from currently 386 to 550 μmol mol–1 by 2050 and cause significant stimulation to plant growth. Consequently, in 2007 and 2008, Australian grains free-air carbon dioxide enrichment (AGFACE) facilities were established at Horsham (36°45′07″S lat., 142°06′52″E long., 127 m elevation) and Walpeup (35°07′20″S lat., 142°00′18″E long., 103 m elevation) in Victoria, Australia to investigate the effects of elevated CO2, water supply and nitrogen fertiliser on crop growth. Understanding the distribution patterns of CO2 inside AGFACE rings is crucial for the interpretation of the crop growth data. In the AGFACE system, the engineering performance goal was set as having at least 80% of the ring area with a CO2 concentration [CO2] at or above 90% of the target concentration at the ring-centre for 80% of the time. The [CO2] was highly variable near the ring-edge where CO2 is emitted and declined non-linearly with the distance downwind and wind speeds. Larger rings maintained the target [CO2] of 550 μmol mol–1 at the ring-centres better than the smaller rings. The spatial variation of [CO2] depended on ring size and the gap between fumigation and canopy heights but not on wind speeds. The variations in the inner 80% of the rings were found to be higher in smaller rings, implying that the larger rings had more areas of relatively uniform [CO2] to conduct experiments.


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