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Efficient chip cooling has become particularly important with the rapid development of high heat flux electronic chips. In this study, a cooling system for electronic chips using dry ice as the cooling medium is developed. The combination of jet impingement and phase change sublimation was employed to achieve efficient cooling by utilizing the Joule-Thomson effect to generate dry ice. The impact of the ratio of heatsink height to inlet diameter (H/D) and dry ice jet velocity on the heat transfer characteristics of the heatsink is investigated by theoretical calculations and experimental tests. The results showed that the optimal heat transfer coefficient was achieved when H/D was 4, 12.76% to 43.28% higher than other H/D values. The chip temperature could be maintained below 38.69°C, which was 8.79% to 36.62% lower than other H/D values, and the heat flux reached 428.92W/cm2. The chip temperature could be effectively regulated by controlling the dry ice flow rate. Furthermore, a comparison with other cooling methods indicated that the dry ice jet cooling system was more suitable for cooling high heat flux electronic devices. The research findings laid the foundation for dry ice cooling of high heat flux chips. [ABSTRACT FROM AUTHOR]

[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]

In order to effectively improve the cold energy recovery efficiency and thermodynamic performance of liquid hydrogen regasification process, a novel type of liquid hydrogen cold energy cascade utilization (RC-HT-AS-DI-CS-AC) system is proposed, which includes Rankine cycle power generation (RC), hydrogen turbine power generation (HT), air separation (AS), production of dry ice (DI), cold storage (CS) and air conditioning (AC). A comprehensive energy, exergy and economic analysis is carried out to compare the proposed system with a comparison system scheme (CSS). For RC-HT-AS-DI-CS-AC system, the energy efficiency of overall system is 79.74%. The cold energy provided by the hydrogen stream achieve 182.31 kW, which is 61.18% increase compared with the CSS. The acquired exergy and exergy efficiency of the RC-HT-AS-DI-CS-AC system increase by 119.6% and 115.9% compared with the CSS. It reveals the importance of liquid hydrogen pressurization to improve exergy efficiency for overall system. However, in the economic analysis, the total annual cost (TAC) of the system of RC-HT-AS-DI-CS-AC system is 278,400 US $, which is significantly higher than TAC of CSS. As a result, the IRR of CSS and RC-HT-AS-DI-CS-AC systems are 87.39% and 15.10% respectively. Therefore, from a commercial point of view, CSS is more worthy of industrialization. [ABSTRACT FROM AUTHOR]

Changes in Arctic sea ice have exerted remarkably effects on the Eurasian climates, but it is unclear whether Arctic sea ice also contributes to Northwest China's ongoing summer drought. This study investigates the influence of the interannual variability of Arctic sea ice on the June drought in Northwest China from 1979 to 2021. It reveals that the early‐autumn sea ice in the East Siberian Sea is correlated with drought conditions in June in Northwest China, with a more pronounced connection during the period of 2000/2001–2020/2021 (P2) compared to 1979/1980–1999/2000 (P1). Mitigated drought in Northwest China is associated with anomalously high sea ice concentration (SIC) in the East Siberian Sea. Further analysis suggests that the strengthened link may be due to greater SIC variability in the East Siberian Sea during P2 than P1. In P2, positive early‐autumn SIC anomaly is linked to anomalous northeasterly winds, promoting drier soil and widespread cooling in the East European Plain. This dry soil signal may persist into the ensuing spring and early summer, inducing an anticyclonic circulation anomaly over Siberia, which could facilitate the water vapor convergence in Northwest China, thereby enhancing humidity conditions in the region. The insights from this study could offer valuable information for improved prediction of droughts in Northwest China. Plain Language Summary: This study examines the impact of Arctic sea ice changes on summer droughts in Northwest China. It was found that early‐autumn sea ice in the East Siberian Sea correlates with drought conditions in Northwest China. Increased sea ice concentration appears to help mitigate drought in Northwest China. This connection was stronger between 2000/2001 and 2020/2021 compared to 1979/1980 and 1999/2000. During 2000/2001–2020/2021, more sea ice leads to drier soil and cooling in the East European Plain, which may affect the following spring and early summer, thereby increasing humidity in Northwest China. These findings could improve predictions of drought conditions in Northwest China. Key Points: Study links East Siberian Sea ice to Northwest (NW) China's summer drought, especially after 2000Increased sea ice is linked to soil dryness and cooling in East European Plain, possibly subsequently enhance humidity in NW ChinaInsights on Arctic ice variability help predict NW China's droughts, aiding response strategies [ABSTRACT FROM AUTHOR]

Welding often induces residual stresses and undesired distortion in components. The negative impacts of these detrimental residual stresses have prompted researchers to explore methods for preventing or mitigating these stresses. Altering the temperature history can influence residual stress, and employing cold or heating techniques during welding has the potential to reduce harmful residual stress. In this study, the dynamically controlled low-stress no-distortion (DC-LSND) method with TIG welding was utilized to reduce the residual stresses in Al alloy 6061-T6. The methodology was simulated using Abaqus software, and the simulation results were validated with experimental data. The Al alloy served as the base metal, alloy (ER-4043) as the filler, and dry ice as the coolant. In the finite element analysis, the longitudinal residual stress at the center of the weld line in TIG welding was calculated to be 77 MPa. In the DC-LSND welding method, this value approached zero. Experimental measurements revealed residual stresses in the center of the welding line to be 183 MPa in conventional welding and 130 MPa in DC-LSND welding. According to the DC-LSND results, a 100% reduction in residual stresses was achieved in the finite element method. In the experimental test, a reduction of approximately 30% in residual stress was observed. The method developed in this research is recommended for application in welding metals and alloys where phase changes do not occur. [ABSTRACT FROM AUTHOR]

Background: The control and prevention of mosquito-borne diseases is mostly achieved with insecticides. However, their use has led to the rapid development and spread of insecticide resistance worldwide. Health experts have called for intensified efforts to find new approaches to reduce mosquito populations and human-mosquito contact. A promising new tool is the use of electrical fields (EFs), whereby mosquitoes are repelled by charged particles in their flight path. Such particles move between two or more conductors, and the use of uninsulated copper or aluminum plates as conductors has been proven to be effective at repelling mosquitoes. Here, for the first time, we assess if EFs generated using a single row of insulated conductor wires (ICWs) can also successfully repel mosquitoes, and whether mosquitoes are equally repelled at the same EF strength when the electrodes are a) orientated differently (horizontal vs. vertical placement), and b) spaced more apart. Methodology/Principal findings: Over a period of 23 hours, the number of host-seeking female Aedes aegypti mosquitoes that were successfully repelled by EFs, using ICWs, at EF strengths ranging from 0 kV/cm (control) to 9.15 kV/cm were quantified. Mosquitoes were released inside a 220×220×180 cm room and lured into a BG-Pro trap that was equipped with a BG-counter and baited with CO2 using dry ice. Mosquitoes had to pass through an EF window, that contained a single row of ICWs with alternating polarity, to reach the bait. The baseline interaction between EF strength and repellency was assessed first, after which the impact of different ICW orientations and ICW distances on repellency were determined. Over 50% of mosquitoes were repelled at EF strengths of ≥ 3.66 kV/cm. A linear regression model showed that a vertical ICW orientation (vertical vs. horizontal) had a small but insignificant increased impact on mosquito repellency (p = 0.059), and increasing ICW distance (while maintaining the same EF strength) significantly reduced repellency (p = 0.01). Conclusions/Significance: ICWs can be used to generate EFs that partially repel host-seeking mosquitoes, which will reduce human-mosquito contact. While future studies need to assess if (i) increased repellency can be achieved, and (ii) a repellency of 50–60% is sufficient to impact disease transmission, it is encouraging that EF repellency using ICWs is higher compared to that of some spatial repellent technologies currently in development. This technology can be used in the housing improvement toolkit (i.e. preventing mosquito entry through eaves, windows, and doors). Moreover, the use of cheap, over-the-counter ICWs will mean that the technology is more accessible worldwide, and easier to manufacture and implement locally. Author summary: Mosquito-borne diseases cause significant public health challenges worldwide. To control and prevent the spread of these diseases, mainly insecticides are used to reduce the mosquito population sizes and/or prevent human-mosquito contact. However, their excessive usage has led to the rapid development of insecticide resistance which warrants the need for the development of new mosquito control tools. This study investigates the use of electric fields that are created between insulated conductor wires to repel Aedes aegypti mosquitoes. We found that electric fields can effectively repel over 50% of host-seeking female Aedes aegypti mosquitoes at electric field strengths of ≥ 3.66 kV/cm. There are several advantages to using this novel mosquito control tool, which includes the affordability and accessibility of wires, making the technology suitable for widespread implementation especially in low-middle income countries that are mostly affected by mosquito-borne diseases. This technology has the potential to reduce human-mosquito contact which is a critical factor in mosquito-borne disease transmission. [ABSTRACT FROM AUTHOR]

The document is a corrigendum for a paper published in the European Journal of Organic Chemistry. The authors acknowledge two mistakes in Scheme 2a and Figure 3 of their initial paper. They explain that the synthetic sequence they reported for the Val and Ile building blocks did not lead to the intended compound, but instead formed a regioisomer. They provide an alternative synthesis for the Val building block and state that their previous publications are indirectly affected by the incorrect version of the pyridine building blocks. The document also includes experimental procedures and spectroscopic characterization of the new compounds. [Extracted from the article]

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]

Dry ice blasting is a technology that has been widely studied and applied in different industrial sectors as an alternative to the use of solvent, water, or abrasive spraying methods. It is a CO2 spraying system capable of balancing efficiency and sustainability with a wide variety of equipment available on the market. This study analyses and compares cryo-cleaning equipment manufactured by pioneering companies in the cryogenic industry. Based on data sheets, safety data sheets, and contact with manufacturers, a quantitative comparative study has been carried out. The aim of this study is to identify those with the best performance, efficiency, and adaptability to operational and environmental requirements. The results reflect the strengths and weaknesses of the equipment in terms of occupational safety and operability. These have been discussed and evaluated, recognising improvements of this technology, which is capable of removing surface layers of different natures without altering the underlying substrate. [ABSTRACT FROM AUTHOR]

The article discusses non-invasive sampling methods for genotyping in research involving genetically modified mice, aligning with the 4R principle of animal welfare. The study focuses on using oral swabs and hair samples as alternatives to invasive biopsies, showcasing benefits such as decreased risk of cross-contamination, large-scale automated workflow, and faster turnaround times. The research demonstrates the efficacy of non-invasive methods for genotyping, providing a more humane and efficient approach in line with European regulations and animal welfare guidelines. [Extracted from the article]

Alpha-synuclein (a-syn) aggregation is associated with neuronal death and the pathological hallmark of Parkinson's disease (PD). The a-syn preformed fibril model (a-syn-PFFs), reflects a-syn aggregation and is currently used in PD studies. To pass through the cell membrane, long fibrils should be fragmented by sonication. In our study, the effects of temperature, pulse modifications and/or device type on the sonication of a-syn-PFFs were investigated. Sonication was performed ultrasonic bath and in laminar-flow cabinet with probe sonicator. Dilutions were made from 5 µg/µl a-syn-PFFs stock in sterile-filtered dH2O to a final concentration and volume of 0.1 µg/µl and 200µl, respectively. Sonication was performed in an ultrasonic bath containing water at 10°C for 1 hour. All probe sonications were performed at 30% amplitude for 1 minute and 20 repetitions. The effect of temperature on sonication has been evaluated by performing sonication at room temperature (RT), in ice and in ice surrounded by dry ice. Also, the effects of pulse duration on sonication were evaluated using pulse durations of 1second(sec) on/1sec off, 3sec on/3sec off and 5sec on/5sec off. Furthermore, by waiting one minute between each sonication cycle, the heat released by the probe was prevented from affecting the fibrillar structure. The particle size was measured in triplicate by dynamic light scattering method. For transmission electron microscopy, formvar/carbon-coated grids were run through ddH2O-sonicated fibril-uranyl acetate solutions and kept dry until examined. Due to the variation in breakage of long a-syn fibrils, the effect of different parameters on sonication was investigated. In comparison of pulse durations, 5sec on/5sec off application produced shorter fibrils. Comparing the temperature interventions, lowering the temperature decreased the fibril size at 1sec on/1sec off settings but increased it at 3sec on/3sec off and 5sec on/5sec off. However, the shortest fibrils were obtained by sonication for 5sec on/5sec off at RT. [ABSTRACT FROM AUTHOR]

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Dry ice is widely used in the chemistry research settings as an excellent coolant. Herein, we report a case study of a graduate student researcher who lost consciousness while retrieving 180 lbs of dry ice from a deep dry ice container. We share the details of the incident and the lessons learned from it to promote safer handling of dry ice in these situations.

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]

Dry ice pulsed sublimation spray cooling (PSSCDI) is an innovative, efficient, energy-saving, and fast cooling method for the thermal management of chip-level electronic components with high thermal load in the aerospace field. Aiming at the heat transfer mechanism of dry ice sublimation spray cooling, a heat transfer model of pulsed dry ice sublimation spray cooling based on flow discretization is proposed in this paper. According to the heat transfer mechanism and the formation mechanism of dry ice reflected by the Joule–Thomson effect, the experimental platform of pulsed dry ice sublimation spray cooling was designed and built. The relationship between spray height, spray flow rate, and spray cone Angle was determined by experiments, and the best spray height was determined. The effects of mass flow rate, pulse period, and duty cycle on heat transfer characteristics of pulsed dry ice sublimation spray were investigated experimentally. The experimental results show that the instantaneous temperature change process of simulated heat source under different working conditions can be divided into three stages: heating, cooling, and constant temperature. The heat flux and heat transfer coefficient of pulsed dry ice sublimation spray cooling under high heat load increase with the increase of the duty ratio and mass flow of dry ice spray, but decrease with the increase of pulse period. However, the heat flux of the duty cycle and heat transfer coefficient of the duty cycle decrease with the increase of duty cycle, which indicates that under the premise of considering dry ice consumption, a lower duty cycle will make pulsed dry ice spray cooling have a higher heat transfer efficiency. When the mass flow rate of dry ice spray is 13 g/s, the pulse period is 0.2 s, the duty cycle is 50 %, the heating power is 40W, the relative optimal cooling heat flux is 48 W/cm2, and the relative optimal heat transfer coefficient is 5400 W/(m2·K). [ABSTRACT FROM AUTHOR]

In the last few years, several studies have emphasized the existence of injury-specific EV "barcodes" that could have significant importance for the precise diagnosis of different organ injuries in polytrauma patients. To expand the research potential of the NTF (network trauma research) biobank of polytraumatized patients, the NTF research group decided to further establish a biobank for EVs. However, until now, the protocols for the isolation, characterization, and storage of EVs for biobank purposes have not been conceptualized. Plasma and serum samples from healthy volunteers (n = 10) were used. Three EV isolation methods of high relevance for the work with patients' samples (ultracentrifugation, size exclusion chromatography, and immune magnetic bead-based isolation) were compared. EVs were quantified using nanoparticle tracking analysis, EV proteins, and miRNAs. The effects of different isolation solutions; the long storage of samples (up to 3 years); and the sensibility of EVs to serial freezing–thawing cycles and different storage conditions (RT, 4/−20/−80 °C, dry ice) were evaluated. The SEC isolation method was considered the most suitable for EV biobanking. We did not find any difference in the quantity of EVs between serum and plasma-EVs. The importance of particle-free PBS as an isolation solution was confirmed. Plasma that has been frozen for a long time can also be used as a source of EVs. Serial freezing–thawing cycles were found to affect the mean size of EVs but not their amount. The storage of EV samples for 5 days on dry ice significantly reduced the EV protein concentration. [ABSTRACT FROM AUTHOR]

In this study, the thermo-mechanical behaviour of densified veneer wood (DVW) for cryogenic applications like load-bearing insulation elements for liquid energy sources is investigated. Mechanical tests with compression parallel and transverse to the veneer plane were performed after conditioning the material at five temperature levels: +60°C, +20°C, −40°C, −78°C (dry ice) and −196°C (liquid nitrogen). The investigations showed increasing compression moduli but also increasing brittleness with decreasing temperature. The compressive strength increased with decreasing temperature until about −30°C. Below this temperature, the strength slightly decreased again. The specific heat capacity was determined in the range of −150°C to +60°C and showed a linear dependency on temperature below +20°C. Above +20°C, a non-linear increase is observed due to evaporation of bound water. Finally, a technique is presented to mould DVW boards transverse to the lamination direction with a thermo-hygro-mechanical process in order to reduce waste material associated with commonly used chipping techniques. [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]

Simple Summary: Liquid nitrogen (LN) is usually used for semen cryopreservation. The most significant point is that it has no time or space restrictions, maximizing the use of high-quality males for breeding. Dry ice is also one of the earliest media used in animal semen cryopreservation. The efficiency of dry ice cryopreservation is lower than that of LN. However, compared with LN, dry ice has an advantage in transportation, as it permits express delivery and can be carried on trains and high-speed railways. Therefore, using dry ice as a cold source for preserving and transporting ultralow-temperature-preserved semen liquid has received extensive attention from scholars. It has been demonstrated in frozen semen from mice and cattle that dry ice can be used as a reliable cold source for transportation. For this reason, we simulated a dry ice transportation environment by placing ultralow-temperature-frozen semen in a foam box with sufficient dry ice to maintain it for one week. We found that one week of storage in dry ice did not cause significant damage to porcine spermatozoa. The effects on the semen were essentially the same as those of LN storage when the dry-ice-preserved spermatozoa were transferred to LN again after one week. To address the safety problems posed by the transportation of boar semen using LN, this study was conducted on the short-term storage of frozen boar semen in dry ice (−79 °C). Boar semen frozen in LN was transferred to dry ice, kept for 1 day, 3 days, 5 days, 7 days, or 8 days, and then moved back to LN. The quality of frozen semen stored in LN or dry ice was determined to evaluate the feasibility of short-distance transportation with dry ice. The results showed that 60 °C for 8 s was the best condition for thawing frozen semen stored in dry ice. No significant differences in spermatozoa motility, plasma membrane integrity, or acrosome integrity were observed in semen after short-term storage in dry ice compared to LN (p > 0.05). There were no significant changes in antioxidant properties between storage groups either (p > 0.05). In conclusion, dry ice could be used as a cold source for the short-term transportation of frozen boar semen for at least 7 days, without affecting sperm motility, morphological integrity, or antioxidant indices. [ABSTRACT FROM AUTHOR]

The New Journal of Chemistry, published by The Royal Society of Chemistry and the Centre National de la Recherche Scientifique, contains a variety of research papers on topics such as graphite exfoliation, EPR characterization of N-oxyl radicals, anticancer efficacy, protoplast regeneration, semiconducting carbon nanotubes, and electrochemical sensing. The journal aims to provide new directions in chemistry and offers valuable insights and research findings for library patrons conducting research in these areas. The document is a list of papers published in the journal, covering a range of topics in chemistry and materials science, including pH-responsive nanotheranostics, synthesis of fused molecules, removal of tetracycline from water, and comparison of different species using UPLC-Q-TOF-MS. [Extracted from the article]

Herein, we describe the possibility of using solid CO2, also known as dry ice, as an exfoliating agent for thermal-assisted exfoliation of graphite. Used dry ice has been chosen over supercritical CO2 for its easy availability after storage purposes. HRTEM analysis showed the increased spacing between the stacked graphite layers after exfoliation. BET and Raman analyses provided evidence for an increased surface area and quantity of defects for the exfoliated graphite powder. VSM analysis showed a ∼three-fold improvement in magnetization in the exfoliated graphite powder sample compared to the control. [ABSTRACT FROM AUTHOR]

Gas hydrates represent an attractive opportunity for gas storage. These ice-like structures can be produced both for the final disposal of greenhouse gases such as carbon dioxide in the solid form and for the storage of energy gases, such as methane, propane, and others, with the possibility of reaching energy densities comparable with those of pressurised vessels, but at lower pressures. In addition, gas hydrates can be directly produced for their capability to act as phase change materials at temperatures higher than 0 °C. This research deals with cold energy storage via the production of gas hydrate into a lab-scale apparatus. Hydrates were produced with pure carbon dioxide and with CO2/N2 mixtures (70/30 and 50/50 vol%). For each mixture, the amount of energy spent for hydrates production and cold energy stored were calculated, and the results were compared among each other. The addition of nitrogen to the system allowed us to maximise the energy stored/energy spent ratio, which passed from 78.06% to 109.04%; however, due to its molecular size and the consequent impossibility to stabilise the occupied water cages, nitrogen caused a reduction in the total quantity of hydrates produced, which was obviously proportional to the energy stored. Therefore, the concentration of nitrogen in the mixtures need to be carefully determined in order to optimise the Estored/Espent ratio. [ABSTRACT FROM AUTHOR]

• Dye ingress method for low temperature container closure integrity testing. • CCI of glass prefillable syringes in deep-frozen conditions (down to -80 °C). • Low temperatures cause integrity failure of elastomers in common primary packaging. • Strong agreement between CCIT results by probabilistic and deterministic methods. Development of novel pharmaceutical drug modalities has created a need for frozen storage and transportation. Accurate and easy assessment of container closure integrity (CCI) in frozen conditions remains a challenge. Thus, container closure systems (CCS) suitable for low temperatures have been primarily restricted to vials despite the growing popularity of prefillable syringes (PFS) for parenteral administration. A new dye ingress test method, suitable for testing at low temperatures, was developed and applied to PFS across a range of deep-frozen temperatures. The method is versatile and can easily be extended to other common CCS formats over a wide range of temperatures including storage on dry ice (-80 °C). This new method was paired with an orthogonal technique, laser-based CO 2 headspace gas analysis, to evaluate the CCI of a glass PFS at temperatures from -50 °C to -80 °C. Both test methods showed comparable results and consistent CCI failure below a temperature of -70 °C. The primary mode of failure was the plunger-to-barrel interface, likely attributable to dimensional changes and loss of elasticity. This study demonstrates the temperature dependent CCI behavior of glass PFS and underscores the importance of thorough characterization of package integrity for deep frozen drug products. [ABSTRACT FROM AUTHOR]

In this work, an additive manufacturing process for extruding fully compounded thermosetting elastomers based on fluorine-containing polymer compositions is reported. Additive manufacturing printers are designed with a dry ice container to precool filaments made from curable fluoroelastomer (FKM) and perfluoroelastomer (FFKM) compounds. A support tube guides the stiffened filament towards the printer nozzle. This support tube extends near the inlet to a printer nozzle. This approach allows low-modulus, uncured rubber filaments to be printed without buckling, a phenomenon common when 3D printing low-modulus elastomers via the fused deposition modeling (FDM) process. Modeling studies using thermal analyses data from a Dynamic Mechanical Analyzer (DMA) and a Differential Scanning Calorimeter (DSC) are used to calculate the Young's modulus and buckling force, which helps us to select the appropriate applied pressure and the nozzle size for printing. Using this additive manufacturing (AM) method, the successful printing of FKM and FFKM compounds is demonstrated. This process can be used for the future manufacturing of seals or other parts from fluorine-containing polymers. [ABSTRACT FROM AUTHOR]

This research discusses the development of a high performance composite out of waste plastic that is ultralightweight, thermally insulated, and high impact resistant. Polycarbonate sheet and Cross-linked Polyethylene (XLPE) foam were combined to create the composite, and silicon adhesive was used to fabricate the composite. Polycarbonate sheets are high impact resistant material, high thermal insulation is provided by XLPE foam, and silicon adhesive is used because of its low thermal conductivity. The composite was fabricated using a stacking technique. The composite prototype was then evaluated by experimenting it to dry ice at a temperature of −78.6°C. Drop tests, compression tests, density measurements was carried out, and thermal analysis was carried out using thermogravimetric analysis. The sample can endure low temperatures while maintaining room temperature on the other side, according to a 24 h dry ice test, whilst a drop test demonstrated that it can withstand significant impact loads. A numerical simulation using Abaqus/Explicit was also used to validate the variations in temperature between the outside surface at −20°C and the inside surface maintained at 30°C of the composites when exposed to cold temperature. The result reveals that the hybrid composite are highly promising in terms of thermal insulation. [ABSTRACT FROM AUTHOR]

Abstract 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.

Accidental release of liquid CO 2 can pose a certain risk to people, animals and equipment near release points. In addition to asphyxiation, cryogenic burns and dry-ice inhalation are potential risks that must be considered. In this study, a source model was established considering the formation of dry ice, which can quickly provide the inlet boundary condition for the computational fluid dynamics (CFD) model to simulate the jet dispersion of liquid CO 2. The size distribution of the dry ice particles was described by the Rosin-Rammler expression. The effects of size distribution, initial pressure, liquid mass fraction and orifice size on the temperature, velocity, CO 2 concentration, mass flow rate (nonsublimated dry ice) and survival distance were analysed. A quantitively risk assessment (QRA) method was used to evaluated the joint impact of source strength, dose-effect and impingement distance. The hazard distances associated with asphyxiation, cryogenic burn and dry ice inhalation were assessed. The results showed that the prediction errors of the mass flow rate using the source model were lower than 20 %. The temperature, velocity and CO 2 concentration predicted by the CFD model agree well with the experimental results. The hazard distance was very dependent on and sensitive to the source strength and dose-effect. [Display omitted] [ABSTRACT FROM AUTHOR]

The addition of dry ice as an admixture to cement pastes has many advantages such as improving the compressive strength and sequestration of CO2. However, its effect on the hydration mechanism of cement pastes is still unknown and will be investigated using electrochemical impedance spectroscopy in this paper. Based on the linear correlation of cumulative hydration heat from the isothermal calorimetry test and the logarithm of high-frequency resistivity, a modified Knudson equation is derived. Corresponding hydration kinetic parameters are calculated by applying the boundary nucleation and growth theory and kinetics model, including Avrami, geometrical contraction, and diffusion equations. The boundary area per unit volume (OvB) for the control specimen and specimens with 0.2% and 0.5% cement weight dry ice addition is 0.1171, 0.1250, and 0.1562, respectively, indicating that the dry ice addition increases the surface area of the nucleation process. In addition, the results show that the Avrami equation for monitoring the nucleation process is limited. Regarding the hydration curves, the transition from the nucleation and growth stage to the interaction of phase boundaries (I) stage is delayed by adding dry ice to the mixture. [ABSTRACT FROM AUTHOR]

Dried blood spot (DBS) analysis has existed for >50 years, but application of this technique to fecal analysis remains limited. To address whether dried fecal spots (DFS) could be used to measure fecal bile acids, we collected feces from five subjects for each of the following cohorts: 1) healthy individuals, 2) individuals with diarrhea, and 3) Clostridioides difficile-infected patients. Homogenized fecal extracts were loaded onto quantitative DBS (qDBS) devices, dried overnight, and shipped to the bioanalytical lab at ambient temperature. For comparison, source fecal extracts were shipped on dry ice and stored frozen. After 4 mo, frozen fecal extracts and ambient DFS samples were processed and subjected to targeted liquid chromatographytandem mass spectrometry (LC-MS/MS)-based metabolomics with stable isotope-labeled standards. We observed no differences in the bile acid levels measured between the traditional extraction and the qDBS-based DFS methods. This pilot data demonstrates that DFS-based analysis is feasible and warrants further development for fecal compounds and microbiome applications. NEW & NOTEWORTHY Stool analysis in remote settings can be challenging, as the samples must be stored at (80C and transported on dry ice for downstream processing. Our work indicates that dried fecal spots (DFS) on Capitainer quantitative DBS (qDBS) devices can be stored and shipped at ambient temperature and yields the same bile acid profiles as traditional samples. This approach has broad applications for patient home testing and sample collection in rural communities or resource-limited countries. [ABSTRACT FROM AUTHOR]

Weather radars with dual-polarization capabilities enable the study of various characteristics of hydrometeors, including their size, shape, and orientation. Radar polarimetric measurements, coupled with Doppler information, allow for analysis in the spectral domain. This analysis can be leveraged to reveal valuable insight into the microphysics and kinematics of hydrometeors in precipitation systems. This paper uses spectral polarimetry to investigate precipitation microphysics and kinematics in storm environments observed during the RELAMPAGO field experiment in Argentina. This study uses range height indicator (RHI) scan measurements from a C-Band polarimetric Doppler weather radar deployed during the field campaign. In this work, the impact of storm dynamics on hydrometeors is studied, including the size sorting of hydrometeors due to vertical wind shear. In addition, particle microphysical processes because of aggregation and growth of ice crystals in anvil clouds, as well as graupel formation resulting from the riming of ice crystals and dendrites are also analyzed here. The presence of different particle size distributions because of the mixing of hydrometeors in a sheared environment and resulting size sorting has been reported using spectral differential reflectivity (sZdr) slope. Spectral reflectivity (sZh) and sZdr have also been used to understand the signature of ice crystal aggregation in an anvil cloud. The regions of pristine ice crystals are identified from vertical profiles of spectral polarimetric variables in anvil cloud because of sZh < 0 dB and sZdr values around 2 dB. It is also found that the growth process of these ice crystals causes a skewed bimodal sZh spectrum due to the presence of both pristine ice crystals and dry snow. Next, graupel formation due to riming has been studied and it is found that the riming process produces sZh values of about 10 dB and corresponding sZdr values of 1 dB. This positive sZdr indicates the presence of needle/columnar secondary ice particles formed by ice multiplication processes in the riming zones. Lastly, the temporal evolution of a storm is investigated by analyzing changes in hydrometeor types with time and their influence on the spectral polarimetric variables. [ABSTRACT FROM AUTHOR]

To date, carbon utilization within the concrete industry is predominantly revolved around gaseous and liquid carbon dioxide (CO2), with relatively limited research dedicated to the application of solid CO2. This study was the first to use solid CO2 (dry ice) as an additive in alkali-activated slag and fly ash (AASF) to investigate its influences on the alkali-activation process and various property improvements. Two study systems were designed: one with alkali-activated slag (AAS) as the control group and fly ash (FA) added at substitution rates of 10%, 30%, and 50%; and the other with 50% FA alkali-activated materials (AAM) as the control group and dry ice added at substitution rates of 4%, 8%, and 12%. Several tests were conducted on AASF, encompassing assessments of setting time, compressive strength, and durability (electrical resistivity and chloride ion diffusion coefficient). Furthermore, a comprehensive analysis of its microstructure was undertaken, employing analytical techniques, such as X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA). The results showed that FA substitution effectively mitigated the short setting time of AAS; however, the mechanical properties and durability decreased by approximately 50%. When dry ice was added to AAM concrete, it induced a series of physical and chemical effects that altered the kinetics of the hydration reaction of AAM. Specifically, adding dry ice significantly prolonged the setting time of AAMs. Moreover, this addition did not damage the mechanical properties or durability of AAS(F). [ABSTRACT FROM AUTHOR]

Certain vaccines that have been developed against COVID‐19 require a storage temperature between around −60 and −70°C. It is challenging for logistics to assure these temperature limits. However, the use of dry ice has to be viewed critically for safety and environmental reasons. Additionally, its use is heavily regulated in air cargo. To preserve the cooling chain during transport and to increase the energy efficiency, special transport containers with an incorporated phase‐change material (PCM) can be used. In the first step, PCM candidates were investigated via differential scanning calorimetry (DSC) and in an ultra‐low freezer with a minimal temperature of −85°C. None of the candidates crystallised reliably without nucleating agents. After the initial tests, the eutectic LiBr·5H2O + H2O with a suitable nucleating agent was identified as favourite PCM. Thermal cycling stability tests showed that this PCM crystallises reliably above −80°C and possesses a melting plateau at −67°C. Further tests in vacuum‐insulated transport boxes of the company va‐Q‐tec show that, depending on the box type, the internal temperature stays below −60°C for over 48 h. [ABSTRACT FROM AUTHOR]

The central component of mosquito and vector surveillance programs globally is the adult mosquito trap, which is intended to collect host-seeking mosquitoes. The miniature CDC trap is a widely distributed trap style in part due to its relative affordability and compact nature. Despite already being a simple trap, in-house production methods, such as 3D printing, could improve the accessibility of the CDC trap by eliminating some of the supply chain variables. We present here several trials with the Salt Lake City (SLC) trap, a three-dimensional (3D) printed trap design. Functional assessments were made on secondary components and found no statistically significant differences when comparing CO2 line height (above vs. below fan), battery types (sealed lead acid vs. USB battery pack), and trap body collection shape (funnel body vs. simple/straight body). The SLC trap was compared directly to a commercial equivalent, the ABC trap, with comparative assessment on species diversity and evenness in collections and found to be statistically equivalent on all metrics. Methods also detail an accompanying optional transport system for a pressurized CO2/regulator set-up, should a practitioner elect not to use dry ice. Our final design is presented here with the publicly published stereolithography (STL) files and a detailed outline of the transport container system. Alternative models are available for in-house manufacture of mosquito traps, and we contribute these designs in an effort to stimulate further growth in vector surveillance. Author summary: Mosquitoes are among of the most commonly encountered public health pests when discussing zoonotic infectious diseases. Several specific tools exist to collect host-seeking mosquitoes from the field. The miniature CDC trap is a widely distributed, compact trap type that is best used when baited with carbon dioxide, such as through dry ice or pressurized gas. Even if the miniature CDC trap is among the more accessible variants of host-seeking mosquito traps, there can still be barriers to entry for small/local programs needing to trap, learn about, and make management decisions against their local mosquito species. To facilitate this, the Salt Lake City Mosquito Abatement District (SLCMAD) developed a blueprint for 3D printing your own mini-CDC trap and validated its use against commercial equivalents. If a 3D printer is already available through a nearby institution (University, research institute, WHO centers, etc.), then the total cost without the dry ice is ~$4 USD (at the time of writing) to print this trap, as compared to commercially supplied models being ~$200 USD or more. The SLCMAD will continue to improve on the design specifications to require fewer materials and design plans are available publicly without cost at ThingiVerse under the SLCMAD page. [ABSTRACT FROM AUTHOR]

This document, titled "Cleaning and conservation: recent successes and challenges," discusses the complexities and challenges of cleaning material-based works of art. The article emphasizes the importance of balancing aesthetic and preservation gains with the risks posed by the cleaning process. It also highlights the need for continued innovation and collaboration between conservators, heritage scientists, academics, and industry professionals to develop new tools, knowledge, and approaches in the field of cleaning science. The document includes seventeen original papers that cover various aspects of cleaning science, including the development of new cleaning materials and approaches, as well as the use of analytical and imaging techniques to assess the impact of cleaning procedures. The article also mentions the growing focus on sustainability and environmentally friendly practices in conservation, as well as the benefits of collaborations between different professionals in the field. [Extracted from the article]

• Dry ice particles spray cooling for IGBT of high-speed train is proposed. • The pin-fin heat sink and the straight-fin heat sink are developed. • The cooling characteristics of dry ice particles spray are simulated and tested. • The temperatures of heat transfer substrate of pin fin heat sink are obtained. Aiming at the high efficiency cooling problem of IGBT(Insulated Gate Bipolar Transistor) module of traction converter for high-speed Train, a method of spray cooling with natural dry ice particles was proposed. The heat sinks with pin-fin and straight-fin structure were designed, and the heat sinks with optimum structure size selected by simulation were developed, and the heat sinks were provided with visual shells, as well as single outlet, double outlet and four outlet of the three different ways of outlet. The gas-solid two-phase flow, heat and mass transfer characteristics of dry ice particles in the heat sinks were studied by means of simulation and experiment. By comparison, it is found that the flow and heat transfer in the pin-fin heat sink have a good cooperation, and it is most suitable for the IGBT module with spray cooling of dry ice particles, which can reduce the temperature of IGBT from 70 ℃ to 55 ℃ in 75 s, compared with the fin-free heat sink, the heat transfer performance is improved by 12 %, and the double-outlet pin-fin heat sink has the best effect, the temperature difference of the heat transfer substrate is 19.8 ℃, and the average temperature of the heat transfer substrate is only 22.5 ℃ compared with that of the open type, which is 27.3 ℃ lower. Double outlet dry ice particles spray pin-fin heat sink is an efficient heat sink, thermal resistance is only 0.066 K/W, it can meet the current practical application of high-speed train cooling needs, solve the problem of heat dissipation of IGBT module for high-speed train, it lays a foundation for the development of dry ice particles spray heat sink. [ABSTRACT FROM AUTHOR]

The aim of this work was to develop a novel method for studying the 3D morphology of agglomerates obtained by spherical agglomeration. It has been found, that the combination of shock-freezing the samples in a mixture of ethanol and dry ice followed by an X-ray microtomography measurement leads to useful results. Hereby, the image quality for low absorbing material like the used graphite was enhanced by propagation-based X-ray microtomography, which results in phase contrast images. We also discuss our 3D image post-processing routine, which is used to determine the morphology parameters sphericity, fractal dimension and packing density. Furthermore, a two-dimensional kernel density estimation is used to calculate the joint probability density of agglomerate size and the morphology parameter. In future, this method will be used to determine the morphological behaviour of agglomerates during the different phases of spherical agglomeration. [ABSTRACT FROM AUTHOR]

The article describes the results of experimental research that allowed us to compare the influence of the forming channel shape and its length on the limit value of the force occurring in the process of extruding crystallized carbon dioxide using multi-channel dies. To carry out the research, the authors adopted a method described in the literature, which allows for experimenting using a sublimating material under normal conditions, at a temperature of -78.4°C. Analysis of variance was used for the statistical analysis of the experiment results, which allowed to determine the level of statistical significance of differences between individual populations. Additionally, based on the median and regression values, an attempt was made to fit a function describing the change in the tested values as a function of geometric parameters. This allowed for comparison of the impact of individual variables. The authors did not observe the research results in the available literature, they would discuss the influence of the channel shape of multi-channel systems on the value of the confining force. Therefore, according to the authors, the presented results constitute an important supplement to the available knowledge. [ABSTRACT FROM AUTHOR]