External Ice Research Articles

Experimental study on the influence of gas-blowing flow rate on the cold discharge characteristics of external ice-melting ice storage system

External ice-melting ice storage system has the advantage of fast cold discharge. However, the instability of outlet water temperature limits its practical application. In this paper, an experimental bench is built for testing cold discharge performance of the external ice-melting ice storage system combined with a gas-blowing device based on theoretical analysis. The influence of different gas-blowing flow rates on the vertical temperature distribution inside the ice storage tank, outlet water temperature, cold discharge rate, instantaneous cold discharge capacity, and total cold discharge capacity is analyzed and compared during the cold discharge process by experiments. The experimental results show that as the gas-blowing flow rate increases, the convective heat transfer between the water and ice in the water space of the ice storage tank is enhanced, the outlet water temperature decreases, and the cold discharge rate increases. Through comprehensive analysis, it is found that for a small external ice-melting ice storage system in this experiment, the outstanding comprehensive performance can be achieved with 1L/min gas-blowing flow rate, which. The average outlet water temperature during the latent heat phase is 1.9 °C lower and the cold discharge rate is 34.8 % higher than that without gas blowing.

Research on the Cold Storage Characteristics of Ice Storage Photovoltaic Cold Storage

The ice-on-coil storage tank is one of the core devices in the latent heat cold storage system. The main objective of this study is to couple the solar photovoltaic cold storage with Cold Thermal Energy Storage technology. The internal ice-melting coil energy storage system used the water as a heat transfer fluid for adopting a day and night cold storage control strategy. The experiments were conducted for several days under the conditions of photovoltaic-driven cold storage with and without load for a continuous cold storage. The reasons for the occurrence of ice layers during ice accumulation and melting, as well as the operational economy of the system were analyzed. Moreover, the characteristics of the cold storage tank were summarized. Consequently, when the external ice thickness of the coil was within the range of 27 to 32mm, the ice storage rate reached 35.82% and achieved the optimal refrigeration efficiency in both the coil and the cold storage. The daily ice production in the cold storage tank decreased by an average of 22.06% during continuous operation with load compared to the unloaded operation. However, the daily refrigeration capacity increased by 45.774%. In addition, when cold thermal energy storage was coupled with solar photovoltaic technology, the refrigeration capacity decreased by 7.15% compared to using Cold Thermal Energy Storage technology alone, which resulting in an annual electricity cost saving of 30.20%.

Numerical simulation of convective heat transfer in the discharging process of external ice-melting ice storage systems

The external ice-melting ice storage system was widely used because of its advantages of reducing peak power consumption, reducing energy consumption and emissions, and fast ice melting speed. However, designing the external ice-melting ice storage system proved to be a challenge, and the structure and flow of the water distribution system needed to be fully considered. In particular, the problem of unstable outlet water temperature limited the practical application of the external melting ice storage system. Aiming at the problem of unstable outlet water temperature, a three-dimensional CFD phase change model was constructed in this paper. By comparing with the experimental data, the impact of varying water flow rates on the thermal and cooling properties of the was investigated. The results indicated that when the water flow rate was 226 ml/min for the system with an ice thickness of 74 mm, the outlet temperature of the ice storage tank was consistently below 5°C, the Nusselt number of ice and water remained constant, and the convective heat transfer effect was improved. The numerical simulation results provided guidance for the design and practical application of the water distribution system of the external melting ice storage system.

Experimental and numerical study of ice storage and melting process of external melting ice coil

Ice storage air conditioning technology could achieve “peak cut” by storing ice during the valley period, melting ice during the peak period to achieve the role of peak load regulation. At the same time, it can promote consumption of renewable energy. This study deals with the experimental and numerical analysis of the solidification and melting processes of coiled ice storage. From the experimental observation, it was observed that the outer surface of the lower side of the coil was the first to form an ice layer. Then the outer surface of the upper side begins to form an ice layer, and the growth rate of the ice layer is faster than that of the lower side. The average growth rates of the ice layer on the upper and lower side are 0.112 mm/min and 0.079 mm/min, respectively. The density variation of water and natural convection were considered in this analysis. The numerical simulation results well match the phenomena and results of experimental research. The influence of different directions of cooling water inlet on the melting rate was also compared in this paper. Under the same initial conditions and boundary conditions, the melting process in the Mode 1 (along the coil) cools down faster; The ice melting process in Mode 2 (perpendicular to the coil) can provide more stable cooling, and the cooling duration is 130 s longer than that in Mode 1.

Adding sea ice effects to a global operational model (NEMO v3.6) for forecasting total water level: approach and impact

Abstract. In operational flood forecast systems, the effect of sea ice is typically neglected or parameterized solely in terms of ice concentration. In this study, an efficient way of adding ice effects to the global total water level prediction systems, via the ice–ocean stress, is described and evaluated. The approach features a novel, consistent representation of the tidal relative ice–ocean velocities, based on a transfer function derived from ice and ocean tidal ellipses given by an external ice–ocean model. The approach and its impact are demonstrated over four ice seasons in the Northern Hemisphere, using in situ observations and model predictions. We show that adding ice effects helps the model reproduce most of the observed seasonal modulations in tides (up to 40 % in amplitude and 50∘ in phase for M2) in the Arctic and Hudson Bay. The dominant driving mechanism for the seasonal modulations is shown to be the under-ice friction, acting in areas of shallow water (less than 100 m) and its accompanied large shifts in the amphidromes (up to 125 km). Important contributions from baroclinicity and tide–surge interaction due to ice–ocean stress are also found in the Arctic. Both mechanisms generally reinforce the seasonal modulations induced by the under-ice friction. In forecast systems that neglect or rely on simple ice concentration parameterizations, storm surges tend to be overestimated. With the inclusion of ice–ocean stress, surfaces stresses are significantly reduced (up to 100 % in landfast ice areas). Over the four ice seasons covered by this study, corrections up to 1.0 m to the overestimation of surges are achieved. Remaining limitations regarding the overestimated amphidrome shifts and insufficient ice break-up during large storms are discussed. Finally, the anticipated trend of increasing risk of coastal flooding in the Arctic, associated with decreasing ice and its profound impact on tides and storm surges, is briefly discussed.

A numerical simulation and analysis of the discharge characteristics and heat transfer performance during the ice-storage system

During the ice melting process of the external ice-melting ice storage system, there is uneven ice melting in the different height of the ice layer, which directly affects cold discharge characteristics. Reasonable water flowrate of the distributor can improve cold discharge characteristics. A 3D dynamic mesh model was built using the computational fluid dynamics (CFD) method, phase change interface movement with time was tracked. And the ice-water heat transfer characteristics at different heights were analyzed and the influence of water distributor's flowrate ice-water mixture heat transfer performance and cold discharge characteristics during ice-melting process were also explored. The results showed that the ice layer above 30 mm height, The Nusselt number of water space averagely increased 23.8 % when the height had 5 mm increment. When the water flowrate increased by 0.01 g/s, the average Nusselt number of the water space increased by 6.7 % and the water outlet temperature increased by 12 % on average. Though the increasing of water flowrate can improve the convective heat transfer between ice and water, it also resulted in the standard temperature deviation and water outlet temperature increase. Under the premise of satisfying the cooling load, the water flowrate of the distributor should not be excessive.

Epistaxis Treatment Options: Literature Review.

Epistaxis means bleeding from nostrils, nasal cavity or nasopharynx. To summarize the available epistaxis treatment options. Methods: 61 articles published in the last 20years were included. Duplicate records, irrelevant and inaccessible ones were excluded. Epistaxis can be treated with first aid measures such as external pressure and ice packing and applying topical agents, e.g. oxymetazoline that stops 65-75% of nosebleeds in A&E. Also, with electrocautery which is more effective and has fewer recurrences (14.5% vs. 35.1%) than chemical cauterization and applying tranexamic acid that promotes hemostasis in 78% of patients, versus 35% and 31% respectively in patients treated with oxymetazoline and nasal packing. Furthermore, nasal packing can be applied with non-absorbable materials, e.g. petroleum jelly, BIPP gauze, PVA nasal tampons (Merocel), Foley catheter, balloons (Rapid-Rhino), absorbable materials, e.g. nasal tampon (Nasopore), and with newer hemostatic materials which are more effective and with fewer complications, e.g. hemostatic gauzes (Surgicel), thrombin matrix (Floseal), gelatin sponge (Spongostan) and fibrin glue. Moreover, epistaxis can be achieved with endoscopic ligation of arteries, mainly SPA, which is more effective than conventional nasal packing (97% vs. 62%), and with endoscopic cauterizationwhich is more effective than ligation. Finally, for intractable cases embolization can be applied using gelatin sponge, foam, PVA and coils with 80% success rate and comparable efficacy and complications to surgical methods. Epistaxis can be dealt with various methods depending on patient's history and available resources. Newer hemostatic agents in combination with endoscopic methods have advantages over traditional methods.

Revisiting “Non-Thermal” Batch Microwave Oven Inactivation of Microorganisms

Over the last few decades there has been active discussion concerning the mechanisms involved in “non-thermal” microwave-assisted inactivation of microorganisms. This work presents a novel non-invasive acoustic measurement of a domestic microwave oven cavity-magnetron operating at fo = 2.45 ± 0.05 GHz (λo ~ 12.2 cm) that is modulated in the time-domain (0 to 2 minutes). The measurements reveal the cavity-magnetron cathode filament cold-start warm-up period and the pulse width modulation periods (time-on time-off and base-time period, where time-on minus base-time = duty cycle). The waveform information is used to reconstruct historical microwave “non-thermal” homogeneous microorganism inactivation experiments: where tap-water is used to mimic the microorganism suspension; and ice, crushed ice, and ice slurry mixture are used as the cooling media. The experiments are described using text, diagrams, and photographs. Four key experimental parameters are indentified that influence the suspension time-dependent temperature profile. First, where the selected process time > the time-base, the cavity-magnetron continuous wave rated power should be used for each second of microwave illumination. Second, external crushed ice and ice slurry baths induce different cooling profiles due to difference in their heat absorption rates. In addition external baths may shield the suspension resulting in a retarding of the time-dependent heating profile. Third, internal cooling systems dictate that the suspension is directly exposed to microwave illumination due to the absence of surrounding ice volume. Fourth, four separated water dummy-loads isolate and control thermal heat transfer (conduction) to and from the suspension, thereby diverting a portion of the microwave power away from the suspension. Energy phase-space projections were used to compare the “non-thermal” energy densities of 0.03 to 0.1 kJ·m-1 at 800 W with reported thermal microwave-assisted microorganism inactivation energy densities of 0.5 to 5 kJ·m-1 at 1050 ± 50 W. Estimations of the “non-thermal” microwave-assisted root mean square of the electric field strength are found to be in the range of 22 to 41.2 V·m-1 for 800 W.

Sini Decoction inhibits TLR4/NF-κB signaling pathway to improve airway remodeling of allergic asthmatic mice

This study aims to explore the effect of Sini Decoction on Toll-like receptor 4(TLR4)/nuclear factor-κB(NF-κB) signaling pathway in the mice with allergic asthma(AA). Forty-eight SPF-grade BALB/c mice were randomly assigned into a blank control group, a model group, a dexamethasone group, and high-, medium-, and low-dose Sini Decoction groups, with 8 mice in each group. The sensitization solution made of ovalbumin and aluminum hydroxide powder was injected intraperitoneally in other groups except the blank control group which was injected with an equal volume of normal saline. The solution(or normal saline) was injected three times in total with an interval of 7 days. At the same time of sensitization, external cold stimulation and ice water were administered in a 4 ℃ climate box for 20 min every day. After modeling, the mice in each group were administrated with corresponding drugs by gavage for 3 weeks. At the end of administration, pentobarbital sodium(30 mg·kg~(-1)) was used for anesthesia, and then the samples were collected for the determination of various indexes. The phenol red test was conducted to evaluate tracheal excretion function. The histopathological changes of lung tissue were observed via hematoxylin-eosin(HE) staining. Masson staining was employed to reveal the deposition of blue collagen fibers around bronchi in lung tissue and the area occupied by blue collagen fibers was calculated. Immunofluorescence method was used to measure the expression of bronchial type Ⅰ collagen(Col-Ⅰ) and α-smooth muscle actin(α-SMA). The protein and mRNA levels of TLR4, NF-κB, cysteinyl aspartate specific proteinase-1(caspase-1), and interleukin-13(IL-13) were determined by Western blot and real-time fluorescence quantitative polymerase chain reaction(real-time PCR), respectively. Compared with the model group, Sini Decoction significantly increased the phenol red excretion from trachea, lowered the lung inflammation score, reduced subepithelial collagen deposition, and decreased Col-Ⅰ and α-SMA levels. Furthermore, the decoction down-regulated the protein and mRNA levels of TLR4, NF-κB, caspase-1, and IL-13 in mouse lung tissue. In conclusion, Sini Decoction can improve air remodeling by inhibiting the TLR4/NF-κB signaling pathway.

Multi-year evolution of 75 snow and ice deposits in Schachtdolines and Shafts of recently deglaciated karst terrain: Observations from Mount Canin-Kanin, Julian Alps, Europe

Dolines and shafts are common geomorphologies in karst landscapes. When affected also by glacial processes, they are considered an example of glaciokarst landform. In high alpine karst, their typical vertical shape lends itself particularly well to the formation of snow and ice accumulations that can survive the ablation season, potentially becoming perennial. This study analyses the 12-years changes of several permanent snow-ice deposits in Schachtdolines and Shafts (SIDS) and compares them with the mass balance of surrounding external ice bodies. According to recent studies and in contrast with the rest of the Alpine glaciers, ice masses of the area are resilient to climate change and show a slightly positive mass balance in the last decade. The presence of a long term mass balance monitoring program provides an excellent basis for a robust comparison with 75 selected SIDS, all located in the Mount Canin-Kanin massif, in the Julian Alps. Six airborne LiDAR surveys performed from 2006 to 2018 at the end of the ablation season allowed accurate calculation of thickness and volume changes. The measured differences show a general increase in thickness of the SIDS with more than one meter gain, although multi-annual observed variability between the sites is high. The observed 2006–2018 positive mass balance is in agreement with the external cryosphere although SIDS appear even more resilient than the external ice patches to both interannual weather variability and climate forcing.

Flow Characteristics and Heat-Transfer Enhancement of Air Agitation in Ice Storage Air Conditioning Systems

A large number of bubbles generated by the air agitation device in an external melting ice storage system can cause the disturbance of the ice–water mixture, which can enhance the heat transfer and contribute to the reduction in energy consumption. The structural design and optimization of the air agitation device in an external melting ice storage system is the key issue for energy savings. In this study, the influence of different orifice spacings and diameters on the distribution of the gas–liquid flow field, gas holdup, heat-transfer coefficient, and power consumption in the ice storage tank was investigated by numerical simulation. The simulated results showed that the heat-transfer coefficient of the ice–water mixture with air bubbles should be 3–5 times higher than the natural convection when the air superficial velocity is 0.03 m/s. The gas holdup was mainly affected by the orifice spacing, and the maximum varied from 5.0% to 8.2%. When the orifice spacing was less than 150 mm, the gas holdup changed a little in the horizontal direction, and the uniformity became worse when the orifice spacing was larger than 180 mm. An orifice diameter larger than 3 mm can improve the heat transfer and cause less air-compressing energy consumption, which decreased by approximately 1.62%.

The Effectiveness of Active External Warming of Patient Concurrently With Ice Application on the Incision Site on Post-Thoracotomy Pain and Analgesic Consumption.

The aim of study is to investigate the effects of active external warming of patient concurrently with application of ice to incision site on thoracotomy pain and analgesic consumption. The research is a quasi-experimental design with control and study groups. The study was conducted in 2018 and 2019. A total of 70 patients were included in the study: 35 in the control group and 35 in the study group. The mean verbal pain scale values were significantly lower in the intervention group (2.85 point) than in the control group (4.57 point; p < .001). Opioid consumption rate was high in control group patients (77.1% tramadol 30 mg; 45.7% morphine sulfate 5 mg) In contrast, the rate of opioid consumption was lower in patients in the intervention group (40% tramadol 30 mg; 17% morphine sulfate 5 mg). Active external warming and ice application on the incision area, could reduce the intensity of thoracotomy pain.

Numerical Simulation on the Structural Design of a Multi-Pore Water Diffuser during the External Ice Melting Process of an Ice Storage System

A water diffuser is a critical auxiliary equipment for an ice storage system during the external ice melting process. This paper proposes a linear multi-pore water diffuser for an ice storage system with 500 t of refrigeration capacity to enhance the performance of external ice melting. By establishing a three-dimensional two-phase volume of fluid (VOF) model, different structural designs of water diffusers for the ice storage device are numerically examined regarding the degree of turbulence, flow velocity, and pressure drop. The results show that the optimal water diffuser with five rows of trunk pipe and six perforated pores arranged in per row of branch pipe with a 4 mm diameter of perforated pores exhibiting a relatively lower degree of turbulence with a lower pressure drop compared with the other designs in this study. Meanwhile, the influence of the flow velocity on the ice melting process is also investigated by a numerical model of ice melting. It is found that the fed flow velocity from the main pipe inlet exhibits a great impact on the external ice melting process. Compared with the external ice melting process without the water diffuser, the external ice melting process with optimal water diffuser design under flow velocity of 1.0 m s−1 could shorten the overall ice-melting time by 16 h. Additionally, through adjusting the water flow velocity, different output cooling can be realized to provide a fast response speed to the cooling variations in demand of the terminal users with a reduced cost.

Theoretical analysis of frozen wall dynamics during transition to ice holding stage

Series of calculations for the artificial freezing of the rock mass during construction of mineshafts for the conditions of a potash mine in development was carried out. Numerical solution was obtained through the finite element method using ANSYS software package. Numerical dependencies of frozen wall thickness on time in the ice growing stage and ice holding stage are obtained for two layers of the rock mass with different thermophysical properties. External and internal ice wall boundaries were calculated in two ways: by the actual freezing temperature of pore water and by the temperature of –8 °С, at which laboratory measurements of frozen rocks' strength were carried out. Normal operation mode of the freezing station, as well as the emergency mode, associated with the failure of one of the freezing columns, are considered. Dependence of a decrease in frozen wall thickness in the ice holding stage on the duration of the ice growing stage was studied. It was determined that in emergency operation mode of the freezing system, frozen wall thickness by the –8 °C isotherm can decrease by more than 1.5 m. In this case frozen wall thickness by the isotherm of actual freezing of water almost always maintains positive dynamics. It is shown that when analyzing frozen wall thickness using the isotherm of actual freezing of pore water, it is not possible to assess the danger of emergency situations associated with the failure of freezing columns.

Cryoprotective effect of silver carp muscle hydrolysate on baker's yeast Saccharomyces cerevisiae and its underlying mechanism.

Cryoprotective effect of silver carp muscle hydrolysate (SCMH) on baker's yeast (Saccharomyces cerevisiae) was examined by analyzing the growth and survival of the yeast during freeze–thaw cycles, and the physicochemical properties [ultrastructure, intracellular proteins and fatty acids, external ice formation (EIF) and internal ice formation (IIF), freezable water content] of yeast cells with or without SCMH through transmission electron microscopy, SDS‐PAGE, GC‐MS, and differential scanning calorimetry. The 4% of SCMH treatment exhibited good yeast cryoprotective activity and increased the yeast survival rate from 0.71% to 90.95% after 1 freeze–thaw cycle as compared to the control. The results demonstrated that the addition of SCMH could attenuate the freeze damage of yeast cells, prevent the degradation or loss of soluble proteins, and increase the composition and absolute content of fatty acids. Besides, the addition of 4% SCMH caused a drop in the EIF peak temperature (from −17.95℃ to −25.14℃) and a decrease in the IIF and freezable water content of yeast cells.

Experimental investigation of ice melting system with open and closed ice-storage tanks combined internal and external ice melting processes

A new ice-storage experimental system with a closed (CIST) and an open (OIST) ice-storage tank has been exploited, with which the external ice melting processes are studied experimentally. Furthermore, the researches on combinations of external and internal ice melting have been carried out. The experiments indicate that the cold release rate of CIST is more stable than that of OIST under the same conditions, especially, the cold release rate of OIST decreases significantly at the later stage of the discharging process. The outlet temperature of the discharge water flowing from the bottom-to-top (Mode 1) is lower than that from the top-to-bottom of the ice-storage tank (Mode 2). With the relatively lower volumetric-flow rate, the outlet temperatures of the discharge water rise slowly, meanwhile, the cold release rate is also relatively lower. To solve the problem of “millennial ice” in the external system without an air-agitation device, two types of the combination of external and internal ice melting have been adopted, one is to adopt internal ice melting at first, and then external ice melting, the other is to adopt simultaneously the internal and external ice melting. The experiments show that the cumulative discharging capacity of the latter has been significantly improved.

Aerodynamic characteristics of generic ice shells

Freezing rain and wet snow can cause ice to accumulate on the surface of bridge cables. Subsequently, a rise in temperature and wind can cause ice to shed from the surface of cables. Several instances of ice and wet snow shedding from bridge cables have been observed in Canada. Environmental predictive models have been proposed to predict the ice shedding behaviour and its trajectory from bridge cables. The current study aims at measuring the aerodynamic force and moment coefficients of generic ice fragments detached from a bridge cable as a priori for a subsequent ice trajectory model. Nine representative generic, ice shells were selected to represent different aspect ratios, curvatures, ice thicknesses, and external ice surface conditions. Aerodynamic forces and moments were measured for each of the ice shell models in turbulent flow for a wide range of orientations. The use of a curved shape as opposed to a flat plate resulted in a significant difference in the aerodynamic coefficients. It was found that the aspect ratio was the most important geometric factor in determining the aerodynamic forces and moments on the curved models. The findings of this study will be implemented in future ice trajectory models.

Supercooling and freezing as eco-physiological alternatives rather than mutually exclusive strategies: A case study in Pyrrhocoris apterus

Overwintering insects are categorized either as freeze tolerant or freeze avoiding (supercooling) based on their ability or inability, respectively, to tolerate the formation of ice in their body. The freeze tolerant insects set their supercooling point (SCP) higher for winter to stimulate freezing at higher temperatures, while freeze avoiding insects survive winter in a supercooled state by depressing their SCP. Some supercooling insects, however, were found to survive in frozen state when freezing occurred through inoculation by external ice at mild subzero temperatures. Here, we assessed the potential relevance of inoculative freezing and freeze tolerance strategy in an insect that was so far considered as a classical example of a ‘supercooler’, the linden bug (Pyrrhocoris apterus). Microclimatic conditions of the overwintering microhabitat of P. apterus (leaf litter layer with buffered temperature fluctuations, mild sub-zero extremes, high humidity, and presence of ice) present a potentially high risk of inoculative freezing. We found that P. apterus is highly susceptible to inoculation by external ice. The temperature at which inoculative freezing occurred (above −3°C) was much higher compared to SCP (−16 °C to −20 °C in winter). The insects were inoculated through body openings and across cuticle and were able to survive after freezing. There was, however, a distinct critical ice fraction, corresponding to 38.7–42.8% of total body water, beyond which survival rapidly decreased to zero. We found that P. apterus adaptively reduces the actual ice fraction below critical ice fraction for winter season. Since many insect species overwinter in habitats similar to that of P. apterus, the ability to tolerate freezing after inoculation by external ice crystals could be much more common among ‘supercooling’ insects than it is currently appreciated.

External ice reinforcements for ships in operation

The subject of the proposed article is the external ice reinforcements of the ship hull. Ice reinforcements for the Russian commercial fleet are an urgent topic, but the traditional measures of such matter (replacement of the shell plating, installation of an intermediate frame) are expensive and require a large amount of preparatory work. External reinforcement are an alternative, which is much cheaper than their installation. As a rule, it is performed in the form of a rolling profile of various shapes (most often a semicircle) welded to the outer skin. In addition to the lower cost, they have a number of other advantages.

Mechanisms of frost resistance in Arabidopsis thaliana.

Freezing resistance strategies vary in Arabidopsis depending on origin. Southern accessions may avoid or tolerate freezing, while northern onesare always tolerant and reduce the proportion of freezable tissue water during acclimation. Survival of sub-zero temperatures can be achieved by either avoiding or tolerating extracellular ice formation. Conflicting evidence has been presented showing that detached leaves of Arabidopsis thaliana are either freeze avoiding or tolerant. Here, we used three different natural Arabidopsis accessions from different habitats to investigate the frost resistance strategy of whole plants in soil. Plants were cooled to fixed temperatures or just held at their individual ice nucleation temperature for different time intervals. Tissue damage of whole plants was compared to the standard lethal temperature determined for detached leaves with external ice nucleation. While all detached leaves survived freezing when ice nucleation was externally initiated at mild sub-zero temperatures, whole plants of the southern accession behaved as freeze avoiding in the non-acclimated state. The northern accessions and all cold acclimated plants were freezing tolerant, but the duration of the freezing event affected tissue damage. Because this pointed to cell dehydration as mechanism of damage, the proportion of freezable water in leaves and osmolality of cell sap was determined. Indeed, the freezing tolerant accession Rsch had a lower proportion of freezable water and higher cell sap osmolality compared to the sensitive accession C24 in the cold acclimated state.