scholarly journals Performance Comparison of Gel and Ice Coolants for Cold Chain Packaging

2021 ◽  
Author(s):  
S. Malasri ◽  
◽  
A. Pourhashemi ◽  
T. Podesta ◽  
K. Nicholson ◽  
...  
Keyword(s):  
Performance Comparison ◽  
Expanded Polystyrene ◽  
Phase Changes ◽  
Cold Chain ◽  
Heat Of Fusion ◽  
Temperature Threshold ◽  
Temperature Sensitive ◽  
Latent Heat Of Fusion ◽  
Data Comparison ◽  
Better Than

Temperature-sensitive products are often shipped in an insulated container with a coolant to maintain the interior temperature at a certain temperature threshold. In this study, the performance of two popular coolants, gel and ice, were compared using trendline data. Comparison using collected data on some cases were made so that phase changes could be observed, which was explained by a study of gel latent heat of fusion that was also performed. The amount of 2.09, 4.19, and 6.28 pounds of each coolant were placed in a 12x12x11.5” expanded polystyrene insulated foam container with a 2-inch wall thickness. In each case, the sealed container was put in a chamber with temperatures of 60-, 90-, and 113-degrees Fahrenheit. Overall, the gel coolant performance was slightly better than the ice coolant.

Determination of the latent heat of fusion and solid fraction evolution of metals and alloys by an improved cooling curve analysis method

2019 ◽  
Vol 140 (4) ◽  
pp. 1825-1836 ◽  
Author(s):  
Carlos González-Rivera ◽  
Anthony Harrup ◽  
Carla Aguilar ◽  
Adrián M. Amaro-Villeda ◽  
Marco A. Ramírez-Argáez
Keyword(s):  
Latent Heat ◽  
Solid Fraction ◽  
Metals And Alloys ◽  
Curve Analysis ◽  
Cooling Curve ◽  
Heat Of Fusion ◽  
Analysis Method ◽  
Latent Heat Of Fusion ◽  
Cooling Curve Analysis

Measurement and Modeling of Latent Heat Release During Freezing of Aqueous Solutions in a Small Container

2000 ◽  
Author(s):  
Ramachandra V. Devireddy ◽  
John C. Bischof ◽  
Perry H. Leo ◽  
John S. Lowengrub
Keyword(s):  
Mass Transport ◽  
Heat Release ◽  
Latent Heat ◽  
Pure Water ◽  
Heat Of Fusion ◽  
Freezing Process ◽  
Latent Heat Release ◽  
Aqueous Systems ◽  
Heat And Mass Transport ◽  
Latent Heat Of Fusion

Abstract The latent heat of fusion, ΔHf of a cryobiological medium (a solute laden aqueous solution) is a crucial parameter in the cryopreservation process. The latent heat has often been approximated by that of pure water (∼ 335 mJ/mg). However, recent calorimetric (DSC - Pyris 1) measurements suggest that the actual magnitude of latent heat of fusion during freezing of solute laden aqueous systems is far less. Fourteen different pre-nucleated solute laden aqueous systems (NaCl-H2O, Phosphate Buffered Saline or PBS, serum free RPMI, cell culture medium, glycerol and Anti Freeze Protein solutions) were found to have significantly lower ΔHf than that of pure water (Devireddy and Bischof, 1998). In the present study additional calorimetric experiments are performed at 1, 5 and 20 °C/min in five representative cryobiological media (isotonic or 1× NaCl-H2O, 10× NaCl-H2O, 1× PBS, 5× PBS and 10× PBS) to determine the kinetics of ice crystallization. The temperature (T) and time (t) dependence of the latent heat release is measured. The experimental data shows that at a fixed temperature, the fraction of heat released at higher cooling rates (5 and 20 °C/min) is lower than at 1 °C/min for all the solutions studied. We then sought a simple model that could predict the experimentally measured behavior and examined the full set of heat and mass transport equations during the freezing process in a DSC sample pan. The model neglects the interaction between the growing ice crystals and is most appropriate during the early stages of the freezing process. An examination of the coefficients in the heat and mass transport equations shows that heat transport occurs much more rapidly than solute transport. Hence, the full model reduces to one in which the temperature profile is constant in space while the solute concentration profile obeys the full time and space dependent diffusion equation. The model reveals the important physical parameters controlling the mass transport at the freezing interface and further elucidates the experimental results, i.e. the temperature and time dependence of the latent heat release.

scholarly journals Effects of Egg Yolk, Glycerol and the Freezing Rate on the Viability and Acrosomal Structures of Frozen Ram Spermatozoa

1975 ◽  
Vol 28 (2) ◽  
pp. 153 ◽  
Author(s):  
PF Watson ◽  
ICA Martin
Keyword(s):  
Latent Heat ◽  
Significant Interaction ◽  
Freezing Point ◽  
Egg Yolk ◽  
Freezing Rate ◽  
Heat Of Fusion ◽  
Significant Deterioration ◽  
Cooling Rates ◽  
Latent Heat Of Fusion ◽  
Cooling Phase

The influence of egg yolk, glycerol and the freezing rate on the survival of ram spermatozoa and on the structure of their acrosomes after freezing was investigated. Egg yolk was shown to be beneficial not only during chilling but also during freezing; of the levels examined, 1� 5 % gave the greatest protection. Although the presence of glycerol in the diluent improved the survival of spermatozoa, increasing concentrations produced significant deterioration of the acrosomes. With closely controlled linear cooling rates, no overall difference was detected in the survival of spermatozoa frozen at rates between 6 and 24�C per min. However, a significant interaction between freezing rate and the inclusion of glycerol in the diluent showed that glycerol was less important at the highest freezing rate. A sudden cooling phase near to the freezing point following the release of the latent heat of fusion was not detrimental to spermatozoa.

scholarly journals Assessment of cold chain and logistics management practices: a cross sectional study in Bundelkhand region of Madhya Pradesh

2018 ◽  
Vol 5 (12) ◽  
pp. 5143
Author(s):  
Ram K. Panika ◽  
Amarnath Gupta
Keyword(s):  
Management Practices ◽  
Cross Sectional Study ◽  
Logistics Management ◽  
Cold Chain ◽  
Temperature Sensitive ◽  
Sectional Study ◽  
Cross Sectional ◽  
Shake Test ◽  
The Status ◽  
Knowledge And Practice

Background: Immunization is one of the most effective disease prevention strategies. Potency of vaccine is dependent on effective management of cold chain system at all levels of vaccine handling. This study was carried out to assess the status of cold chain equipment and logistics management practices, Knowledge and practice of CCHs about cold chain equipment and logistics management.Methods: Cross-sectional study was conducted in all functional cold chain points of Damoh district using structured questionnaires provided by UNICEF.Results: Only 57.14% and 71% CCPs had dedicated space for dry storage and for conditioning of ice packs respectably. 50% CCPs had correct placement of ice-packs inside DFs. Functional thermometer inside every equipment was available in 86% CCPs. Twice daily temperature recording and temperature of ILRs was within normal range in 93% CCPs. Record of power failures and defrosting/cleaning in temperature log books was found in 57% and 43% CCPs. Temp log book was countersigned by facility in charge in 43% CCPs. UIP vaccines were stored within basket in 93%. Fractional IPV was stock out in 29% CCPs and in 07% CCPs OPV vials were found with not usable VVM. 86%, 72% and 64% of CCHs had knowledge on freeze/temperature sensitive vaccines, cold chain pray and, Shake test. In 79% CCPs expired/wasted vaccines were not documented in stock.Conclusions: Most of the components of cold chain and logistics management practices were satisfactory while there is a gap in other components which needs to be improved. 

Risk quantification in cold chain management: a federated learning-enabled multi-criteria decision-making methodology

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Henry Lau ◽  
Yung Po Tsang ◽  
Dilupa Nakandala ◽  
Carman K.M. Lee
Keyword(s):  
Decision Making ◽  
Evaluation System ◽  
Small And Medium Enterprises ◽  
Handling Time ◽  
Cold Chain ◽  
Pairwise Comparisons ◽  
Temperature Sensitive ◽  
Multi Criteria Decision Making ◽  
Firm Level ◽  
Content Type

PurposeIn the cold supply chain (SC), effective risk management is regarded as an essential component to address the risky and uncertain SC environment in handling time- and temperature-sensitive products. However, existing multi-criteria decision-making (MCDM) approaches greatly rely on expert opinions for pairwise comparisons. Despite the fact that machine learning models can be customised to conduct pairwise comparisons, it is difficult for small and medium enterprises (SMEs) to intelligently measure the ratings between risk criteria without sufficiently large datasets. Therefore, this paper aims at developing an enterprise-wide solution to identify and assess cold chain risks.Design/methodology/approachA novel federated learning (FL)-enabled multi-criteria risk evaluation system (FMRES) is proposed, which integrates FL and the best–worst method (BWM) to measure firm-level cold chain risks under the suggested risk hierarchical structure. The factors of technologies and equipment, operations, external environment, and personnel and organisation are considered. Furthermore, a case analysis of an e-grocery SC in Australia is conducted to examine the feasibility of the proposed approach.FindingsThroughout this study, it is found that embedding the FL mechanism into the MCDM process is effective in acquiring knowledge of pairwise comparisons from experts. A trusted federation in a cold chain network is therefore formulated to identify and assess cold SC risks in a systematic manner.Originality/valueA novel hybridisation between horizontal FL and MCDM process is explored, which enhances the autonomy of the MCDM approaches to evaluate cold chain risks under the structured hierarchy.

Cold Chain Logistics in India

2016 ◽  
pp. 159-172 ◽  
Author(s):  
Swapnil Saurav ◽  
Ravi Potti
Keyword(s):  
Supply Chain ◽  
Fruits And Vegetables ◽  
Critical Role ◽  
High Energy ◽  
Cold Chain ◽  
Temperature Sensitive ◽  
Horticultural Crops ◽  
Perishable Goods ◽  
Power Deficit ◽  
Marine Products

Cold Chain refers to the transportation of temperature sensitive products like perishable goods from the point of origin to point of consumption in the food supply chain, which keeps it fresh and edible for a much longer period than in normal conditions. Cold Chain helps in transporting seasonal products and also making it available throughout the year. Two main parts of cold chain are transportation and storage systems. The key Indian industries where cold chain logistics play very important role are fruits and vegetables, milk and milk products (ice cream), Poultry and processed meat, marine products, pharmaceutical (mainly vaccines) and chemicals. An efficient cold chain industry ensures availability of food products as well as prevents spoilage of medicines. Country like India, where infrastructure is one of the major challenges, cold chain plays a critical role. Analysis for this study shows that cold supply chain network does not differ significantly from products to products at least in Indian scenario. Some of the challenges to the growth of sector in India are high energy cost, power deficit, rising real estate cost, lack of logistical support and uneven distribution of capacity. All these challenges bring down the operating margin of a company and makes it not so attractive business sector. But during last couple of years there is a positive environment being created for this sector in India. The growth in organized retail, growing interest in horticultural crops, demand for cold chain logistics from Pharmaceutical industry and various initiatives by government are some of the reasons why there is a renewed interest in this sector especially by private sector players. This study, which is focused on Indian cold chain logistics, analyzes the industry on PEST (Political, Economy, Social and Technology) model and presents top 3 factors on each of these 4 parameters.

scholarly journals Consideration of Latent Heat of Fusion of Ice in Aqueous Solution

Netsu Bussei ◽  
2008 ◽  
Vol 22 (1) ◽  
pp. 18-24
Author(s):  
Tatsunori ASAOKA ◽  
Hiroyuki KUMANO ◽  
Akio SAITO ◽  
Seiji OKAWA
Keyword(s):  
Aqueous Solution ◽  
Latent Heat ◽  
Heat Of Fusion ◽  
Latent Heat Of Fusion
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