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Surveillance is a prime requisite for controlling arthropod vectors like mosquitoes that transmit diseases such as malaria, dengue and chikungunya. Carbon dioxide (CO2) is one of the main cues from vertebrate breath that attracts mosquitoes towards the host. Hence, CO2 is used as an attractant during surveillance of mosquitoes either from commercial cylinders or dry ice for mosquito traps. In the present study, the biogenic carbon dioxide production was optimized with different carbon sources such as glucose, simple sugar and jaggery with and without yeast peptone dextrose (YPD) media using commercial baker's yeast. The results showed that yeast produced more biogenic CO2 with simple sugar as compared to other carbon sources. Further substrate concentration was optimized for the continuous production of biogenic CO2 for a minimum of 12 h by using 10 g of baker's yeast with 50 g of simple sugar added to 1.5 l distilled water (without YPD media) in a 2-l plastic bottle. This setup was applied in field condition along with two different mosquito traps namely Mosquito Killing System (MKS) and Biogents Sentinel (BGS) trap. Biogenic CO2 from this setup has increased the trapping efficiency of MKS by 6.48-fold for Culex quinquefasciatus, 2.62-fold for Aedes albopictus and 1.5-fold for Anopheles stephensi. In the case of BGS, the efficiency was found to be increased by 3.54-fold for Ae. albopictus, 4.33-fold for An. stephensi and 1.3-fold for Armigeres subalbatus mosquitoes. On the whole, plastic bottle setup releasing biogenic CO2 from sugar and yeast has increased the efficiency of MKS traps by 6.38-fold and 2.74-fold for BGS traps as compared to traps without biogenic CO2. The present study reveals that, among different carbon sources used, simple sugar as a substance (which is economical and readily available across the world) yielded maximum biogenic CO2 with yeast. This setup can be used as an alternative to CO2 cylinder and dry ice in any adult mosquito traps to enhance their trapping efficiency of a mosquito surveillance programme.

Traditional sources of carbon dioxide (CO₂), dry ice, and compressed gas, were tested against 3 combinations of food-grade reagents known to generate CO₂using a compact, lightweight generator delivery system with Centers for Disease Control and Prevention light traps. Three 6 × 6 Latin square trials were completed near the Florida Gulf Coast in the Lower Suwannee Wildlife Refuge during the summer of 2013, collecting a total of 31,632 female mosquitoes. Treatments included dry ice, compressed CO₂gas, a control trap (no CO₂), citric acid + sodium bicarbonate, vinegar + sodium bicarbonate, and yeast + sugar. Decreasing order of trap collections (treatment mean number of mosquitoes per trap night ± standard error) were dry ice 773.5 (± 110.1) > compressed gas 440.7 (± 42.3) > citric acid + sodium bicarbonate 197.6 (± 30.4), yeast + sugar 153.6 (± 27.4) > vinegar + sodium bicarbonate 109.6 (± 16.2) > control 82.4 (± 14.0). A 2-way Kruskal-Wallis analysis by treatment, site, and treatment × site interaction identified significant differences between all treatments. Although dry ice and compressed CO₂gas collected significantly more mosquitoes than other combinations (P < 0.05), use of citric acid and sodium bicarbonate or yeast and sugar greatly outperformed unbaited traps and offer a good alternative to dry ice and compressed gas in areas where these agents are not readily available or are difficult to obtain due to logistical constraints. An inexpensive, portable CO₂generator for use with food-grade reagents is described.

Hematophagous arthropods transmit the etiological agents of numerous diseases and as a result are frequently the targets of sampling to characterize vector and pathogen populations. Arguably, the most commonly used sampling approach involves traps baited with carbon dioxide. We report results of a laboratory study in which the performance of carbon dioxide-baited traps was evaluated using measures of baiting intensity, the amount of carbon dioxide released per unit time during trap deployment. We evaluated the effects of trap design, carbon dioxide source, and wind speed on baiting intensity and documented significant effects of these factors on the length of sampling (time to baiting intensity = 0), maximum baiting intensity, and variation in baiting intensity during experimental trials. Among the three dry ice-baited trap types evaluated, traps utilizing insulated beverage coolers as dry ice containers sampled for the longest period of time, had the lowest maximum but most consistent baiting intensity within trials and were least sensitive to effects of wind speed and dry ice form (block vs. pellet) on baiting intensity. Results of trials involving traps baited with carbon dioxide released from pressurized cylinders suggested that this trap type had performance comparable to dry ice-baited insulated cooler traps but at considerably higher cost., (© The Author 2015. Published by Oxford University Press on behalf of the Entomological Society of America.)

Carbon dioxide (CO2) is one of the most relevant and abundant species in astrophysical and atmospheric media. In particular, CO2 ice is present in several solar system bodies, as well as in interstellar and circumstellar ice mantles. The amount of CO2 in ice mantles and the presence of pure CO2 ice are significant indicators of the temperature history of dust in protostars. It is therefore important to know if CO2 is mixed with other molecules in the ice matrix or segregated and whether it is present in an amorphous or crystalline form. We apply a multidisciplinary approach involving IR spectroscopy in the laboratory, theoretical modeling of solid structures, and comparison with astronomical observations. We generate an unprecedented highly amorphous CO2 ice and study its crystallization both by thermal annealing and by slow accumulation of monolayers from the gas phase under an ultrahigh vacuum. Structural changes are followed by IR spectroscopy. We also devise theoretical models to reproduce different CO2 ice structures. We detect a preferential in-plane orientation of some vibrational modes of crystalline CO2. We identify the IR features of amorphous CO2 ice, and, in particular, we provide a theoretical explanation for a band at 2,328 cm(-1) that dominates the spectrum of the amorphous phase and disappears when the crystallization is complete. Our results allow us to rule out the presence of pure and amorphous CO2 ice in space based on the observations available so far, supporting our current view of the evolution of CO2 ice.

Despite radically different environmental conditions, terrestrial and martian dunes bear a strong resemblance, indicating that the basic processes of saltation and grainfall (sand avalanching down the dune slipface) operate on both worlds. Here, we show that martian dunes are subject to an additional modification process not found on Earth: springtime sublimation of Mars' CO(2) seasonal polar caps. Numerous dunes in Mars' north polar region have experienced morphological changes within a Mars year, detected in images acquired by the High-Resolution Imaging Science Experiment on the Mars Reconnaissance Orbiter. Dunes show new alcoves, gullies, and dune apron extension. This is followed by remobilization of the fresh deposits by the wind, forming ripples and erasing gullies. The widespread nature of these rapid changes, and the pristine appearance of most dunes in the area, implicates active sand transport in the vast polar erg in Mars' current climate.

The dry ice sowing experiment (DISE) consisted in adding dry ice to a lake and monitoring the subsequent evasion of carbon dioxide (CO2). DISE allowed us to evaluate two approaches commonly used for measuring aquatic CO2 diffusive fluxes: the boundary layer equation (BLE) from Cole and Caraco (1998) and a particular model of static chamber (SC). CO2 evasion measurements with both approaches were compared to CO2 mass budgets as a relative reference to define their recovery coefficients (p). p for the BLE and the SC over the whole measurement period were 101 +/- 14% and 115 +/- 56%, respectively. Results from discrete sampling intervals revealed that the BLE generally provided estimations in good agreement (80-130%) with the mass budgets during both daytime and nighttime. Variations in p for the BLE were related to wind speed and, consequently, piston velocity (k600). The SC overestimated CO2 evasion during daytime (149 +/- 39%), and underestimated it during nighttime (57 +/- 18%). Variations in p for the SC were related to k600, stemming mainly from the alteration of the air/ water temperature gradient.

There are five known taste modalities in humans: sweet, bitter, sour, salty and umami (the taste of monosodium glutamate). Although the fruitfly Drosophila melanogaster tastes sugars, salts and noxious chemicals, the nature and number of taste modalities in this organism is not clear. Previous studies have identified one taste cell population marked by the gustatory receptor gene Gr5a that detects sugars, and a second population marked by Gr66a that detects bitter compounds. Here we identify a novel taste modality in this insect: the taste of carbonated water. We use a combination of anatomical, calcium imaging and behavioural approaches to identify a population of taste neurons that detects CO2 and mediates taste acceptance behaviour. The taste of carbonation may allow Drosophila to detect and obtain nutrients from growing microorganisms. Whereas CO2 detection by the olfactory system mediates avoidance, CO2 detection by the gustatory system mediates acceptance behaviour, demonstrating that the context of CO2 determines appropriate behaviour. This work opens up the possibility that the taste of carbonation may also exist in other organisms.

Adult mosquito collections were conducted for 12 weeks in two residential areas in Kuala Lumpur. The CDC light traps were compared using dry ice and yeast as sources of carbon dioxide attractants for mosquitoes. The efficacy of the dry ice baited trap was significant over yeast generated CO2 trap. The predominant species obtained were Culex quinquefasciatus, Stegomyia albopicta and Armigeres subalbatus.

The gamma ray spectrometer on the Mars Odyssey spacecraft measured an enhancement of atmospheric argon over southern high latitudes during autumn followed by dissipation during winter and spring. Argon does not freeze at temperatures normal for southern winter (approximately 145 kelvin) and is left in the atmosphere, enriched relative to carbon dioxide (CO2), as the southern seasonal cap of CO2 frost accumulates. Calculations of seasonal transport of argon into and out of southern high latitudes point to meridional (north-south) mixing throughout southern winter and spring.

The authors describe three accidental deaths resulting from occupational hazards involving environmental gas alterations. One involved the displacement of oxygen caused by leakage of liquid nitrogen during the installation of a magnetic resonance imaging system. Two involved elevated environmental carbon dioxide concentrations: dry ice sublimation in a walk-in refrigerator in a research laboratory, and activation of a carbon dioxide fire alarm-extinguisher system by a woman locked in a bank vault. The autopsy findings, scene investigations, and certifications of these deaths, as related to the mechanisms of death, are discussed.

High-resolution images of the south polar residual cap of Mars acquired in 1999 and 2001 show changes in the configuration of pits, intervening ridges, and isolated mounds. Escarpments have retreated 1 to 3 meters in 1 martian year, changes that are an order of magnitude larger than can be explained by the sublimation of water ice, but close to what is expected for sublimation of carbon dioxide ice. These observations support a 35-year-old conjecture that Mars has a large surface reservoir of solid carbon dioxide. The erosion implies that this reservoir is not in equilibrium with the present environment and that global climate change is occurring on Mars.

Using topography collected over one martian year from the Mars Orbiter Laser Altimeter on the Mars Global Surveyor (MGS) spacecraft, we have measured temporal changes in the elevation of the martian surface that correlate with the seasonal cycle of carbon dioxide exchange between the surface and atmosphere. The greatest elevation change (1.5 to 2 meters) occurs at high latitudes ( above 80 degrees ), whereas the bulk of the mass exchange occurs at lower latitudes (below 75 degrees N and below 73 degrees S). An unexpected period of sublimation was observed during northern hemisphere autumn, coincident with dust storms in the southern hemisphere. Analysis of MGS Doppler tracking residuals revealed temporal variations in the flattening of Mars that correlate with elevation changes. The combined changes in gravity and elevation constrain the average density of seasonally deposited carbon dioxide to be 910 +/- 230 kilograms per cubic meter, which is considerably denser than terrestrial snow.

The preservation effectivity of slaughter animal blood for consumptive purposes was studied by a method of non-phrenic action with solidified CO2. The material for studies was full pig blood stabilized with sodium citrate. The course of the changes of the blood properties studied has been described by regression equations. Blood stabilization with solidified CO2 was found to reduce the rate of aerobic microflora growth and of proteolytic changes and to extend the stability period of the coagulation system. The results of sensory studies were related to the boundary values of the studied physicochemical and microbiological quality factors. The admissible periods of blood storage were determined from the results of the studies. It was found that practical preservation of blood stabilized with solidified CO2 was 15 full days at 5 degrees C, 6 days at 10 degrees C and 4 days at 15 degrees C, and it was two, three and four times greater at the three successive temperatures, as compared with the preservation of control blood.

The use of dry ice has increased dramatically in poultry processing plants because of changes in the fast food industry. Concentrations of carbon dioxide in four such plants were measured and were found to exceed the Immediately Dangerous to Life and Health Level (50,000 ppm) inside holding coolers where ventilation is poor. In other areas, where dry ice is delivered to poultry packages, time-weighted average exposures can exceed the threshold limit value of 5000 ppm by substantial margins, even if local exhaust ventilation systems are present. Reports of adverse health effects from carbon dioxide exposure and various control measures are reviewed. Recommendations regarding sampling and analytical techniques also are presented. Operators of poultry plants where dry ice is used need to recognize the occupational hazards of exposure to carbon dioxide.

In the investigation of outbreaks of plague it is frequently more satisfactory to send specimens of suspected material collected in the field to a central laboratory, where usually better facilities for their more detailed examination are available. In the present study the authors have investigated the suitability of solid CO(2) (dry-ice) for the preservation of such material during transit. Three types of preparation were tested: broth suspensions of Pasteurella pestis, the livers and spleens of guinea-pigs dying after being infected with two different strains of P. pestis, and whole carcasses of mice and ground-squirrels infected with the organism. An additional test to ascertain the rate at which animal specimens became frozen and thawed was also carried out.These studies showed that (1) organisms in the various tissues frozen in dry-ice were not adversely affected by such treatment; (2) the survival of P. pestis cells did not depend on the number of organisms present in broth cultures or tissue suspensions, small numbers surviving equally well as large; and (3) plague bacilli contained in whole carcasses, even when present in small numbers, were also successfully preserved. It is concluded from these results, and also from the authors' practical use of the method over several years, that for the transport of plague-suspect materials from the field to the laboratory freezing with dry-ice can be confidently recommended.

[Display omitted] • Simulate breakage and oxidation of clay aging by sonication and plasma treatment. • Investigate the role of surface properties of aged clay in CO 2 hydrate formation. • Disrupted Si-O rings and grafted –OH of VMNs weaken their interaction with water. • Disordered interfacial water caused by clay aging prolong CO 2 hydrate nucleation. Clay-based marine sediments have great potential for safe and effective carbon dioxide (CO 2) encapsulation by storing enormous amounts of CO 2 in solid gas hydrate form. However, the aging of clay with time changes the surface properties of clay and complicates the CO 2 hydrate formation behaviors in sediments. Due to the long clay aging period, it is difficult to identify the role of clay aging in the formation of CO 2 hydrate in marine sediments. Here, we used ultrasonication and plasma treatment to simulate the breakage and oxidation of clay nanoflakes in aging and investigated the influence of clay aging on CO 2 hydrate formation kinetics. We found that the breakage and oxidation of clay nanoflakes would disrupt the siloxane rings and graft hydroxyl on the clay nanoflakes. This decreased the negative charge density of clay nanoflakes and weakened the interfacial interaction of clay nanoflakes with the surrounding water. Therefore, the small clay nanoflakes enriched in hydroxyl would disrupt the surrounding tetrahedral water structure analogous to the CO 2 hydrate, resulting in the prolongation of CO 2 hydrate nucleation. These results revealed the influence of the structure-function relationship of clay nanoflakes with CO 2 hydrate formation and are favorable for the development of hydrate-based CO 2 storage. [ABSTRACT FROM AUTHOR]

This study addresses the control challenges associated with loading low-pressure liquid carbon dioxide carriers (LCO2Cs), which are crucial components of the carbon capture, utilization, and storage (CCUS) chain. It explores the need for stable pressure and temperature control to prevent dry ice formation and ensure efficient cargo handling. The research employed HYSYS dynamic simulations to assess three different control strategies. The simulations assessed each strategy's effectiveness in maintaining stable operating conditions and preventing risks, such as dry ice formation and valve blockages. The study concluded by examining the necessity of pressurization for safe and efficient LCO2 loading and by determining which control strategy is most effective and reliable based on the simulation outcomes. Among the three scenarios examined, Case A, which utilized two control valves, exhibited initial instability due to significant flow coefficient differences, resulting in temperature drops below the CO2 triple point and increasing the risk of dry ice formation. Case C, operating without pressurization, experienced severe pressure fluctuations and prolonged exposure to temperatures below the triple point, posing risks of valve blockages. In contrast, Case B, which uses a remote pressure-reducing valve and a control valve, demonstrated the most stable performance, effectively avoiding dry ice formation and pressure fluctuations, making it the most reliable method for safe LCO2 cargo loading. [ABSTRACT FROM AUTHOR]

Dry ice is one of the world's most in‐demand commodities for cold chain distribution of temperature sensitive products in insulated shippers. A commonly used rule of thumb is that dry ice sublimates about 8% every 24 h, without consideration for dry ice type, size, or geometry. This study explored sublimation rates of dry ice composition (binding agent and density), age, and geometry (size and shape). Dry ice block manufacturing often involves dosing propylene glycol‐water "binder" solution to liquid carbon dioxide. Tests performed in this study revealed that the binding agent did not influence the dry ice sublimation rate. Dry ice density was found to impact sublimation rate. Fresh and aged blocks of similar dimensions and mass were found to have similar performance outcomes. Mass loss curves for pellets and various sized dry ice blocks showed a dependence on surface area and volume. Chunked blocks and pellets with and without binding agent sublimated at similar rates of 2.84 and 2.53% h−1 (w/w), respectively, whereas block varieties with significantly lower surface area to volume ratios had lower sublimation rates of 0.98–1.60% h−1. [ABSTRACT FROM AUTHOR]

When dealing with processes involving the compaction of bulk materials, very often the quality of the product is determined based on density measurements. Methods used in the industry do not produce compacted materials with high degrees of homogeneity. As a result, the quality of the resulting product, interpreted as its density, varies over the cross-section of the product. In this article, the authors present the results of a numerical study involving the analysis of the density distribution of compacted dry ice during the reciprocating process. The Drucker–Prager/cap model was used in this study, which allowed the change in mechanical properties of the compacted material to be taken into account during the simulation of the process. The diameter, height and density of the cylindrical specimens used in the numerical tests were taken as the variable parameters. Thus, as a result of the testing, the authors could formulate conclusions relating to their impact on the homogeneity of the material. [ABSTRACT FROM AUTHOR]

The developments in manufacturing technologies are expected to reduce energy input without compromising product quality. Regarding the material densification process, numerical simulation methods are applied to achieve this goal. In this case, relevant material models are built using functions that describe the variation in mechanical parameters of the material in question due to its deformation. The literature review conducted for this research has revealed a shortage of experimental research methods allowing a determination of the coefficient of friction at low temperatures, approximately 200 K. This article proposes a method for determining the friction coefficient of dry ice sliding against steel. The experimental results were analysed to obtain several functions describing the variation in the coefficient of friction. These functions were then compared using goodness-of-fit indexes. Finally, two functions with similar goodness-of-fit values were chosen. The findings of this research project will complement the already available information and may be used in various research and implementation projects related to the development or improvement of currently used crystallised carbon dioxide conversion processes. [ABSTRACT FROM AUTHOR]