Preparation and Performance of n-Dodecane Microencapsulated Phase Change Cold Storage Materials

Cold chain transportation is currently a hot research topic.Since the traditional refrigeration methods lead to the consumption of large amounts of energy,the search for new energy storage materials is a major trend.In the present contribution,n-dodecane/PMMA microencapsulated phase change materials were prepared by suspension polymerization for ice-temperature cold chain transportation and their preparation parameters were explored using the encapsulation ratio as optimization indicator.The results show that the n-dodecane-containing microcapsules have a maximum encapsulation ratio of 93.2%when using a core-to-wall ratio of 3:1,5%of emulsifier,30%of crosslinker,and 2000 rpm of emulsification speed.The phase transition temperature and enthalpy are-2℃and 195.9 kJ/kg,respectively.The microcapsules prepared with the optimized process parameters have good microscopic morphology,high energy storage efficiency,uniform particle size and good thermal stability,making them ideal materials for cold chain transportation.

Theoretical Analysis of Cold Storage Devices in a CO2 Transcritical/Subcritical Supermarket Refrigeration Plant

This paper proposes a theoretical study of a cold storage system in a CO2 （carbon dioxide） MT （medium temperature） plant for supermarkets application. The aim of this plant strategy is that in the daily hours the storage can export heat form the refrigerant outcoming the gas cooler/condenser whereas during the nightly hours it can be maintained cooled by this latter before its incoming into the evaporator. Besides, the storage can be used for reducing the energy peak consumption, permitting to size the plant on a lower energy target, and it can influence the choice of the optimisation logic of the plant controller, in this work a model for a MT CO2 transcritical/subcritical cycle, able to manage the transient due to the changes of loads and external conditions, is proposed to take into account the evolution with time in a fixed time step. A parametrical analysis has been conduced for understanding the optimal design of the plant. A seasonal analysis is considered too, for understanding the cold storage benefits in different periods of year.

Spatial Pattern Evolution and Influencing Factors of Cold Storage in China

Cold storage is the vital infrastructure of cold chain logistics. In this study, we analyzed the spatial pattern evolution characteristics, spatial autocorrelation and influencing factors of cold storage in China by using kernel density estimation(KDE), spatial autocorrelation analysis(SAA), and spatial error model(SEM). Results showed that: 1) the spatial distribution of cold storage in China is unbalanced, and has evolved from ‘one core’ to ‘one core and many spots’, that is, ‘one core’ refers to the Bohai Rim region mainly including Beijing, Tianjin, Hebei, Shandong and Liaoning regions, and ‘many spots’ mainly include the high-density areas such as Shanghai, Fuzhou, Guangzhou, Zhengzhou, Hefei, Wuhan, ürümqi. 2) The distribution of cold storage has significant global spatial autocorrelation and local spatial autocorrelation, and the ‘High-High’ cluster area is the most stable, mainly concentrated in the Bohai Rim;the ‘Low-Low’ cluster area is grouped in the southern China. 3) Economic development level, population density, traffic accessibility, temperature and land price, all affect the location choice of cold storage in varying degrees, while the impact of market demand on it is not explicit.

The Popularization and Application of Cold Storage Red Blood Cells or Whole Blood at -80 ℃ of the Rh(D) Negative Patients in Surgical Operation

Summary: The efficiency of cold storage red blood cells (CSRBC) or whole blood at -80 ℃ used in 27 Rh(D) negative patients during surgical operation was reported. The Rh(D) negative patients received the transfusion of CSRBC or whole blood stored at -80 ℃ for 180 to 360 days. The changes in the indexes, such as blood TB, DB, K +, Na +, BUN, Cr, urine protein (URPO), UOB, Hb, HCT, serum total protein, relative to hemolytic reaction and blood volume before and after transfusion were observed. The results showed that after transfusion of CSRBC or whole blood 27 cases were negative for urine protein and UOB, and the levels of BUN and Cr were normal (P>0.05). Blood TB, DB, Hb, and HCT were increased, while pH, blood K + and blood Na + was normal with the difference being not significant before and after operation (P>0.05). Plasma protein was decreased, but there was no significant difference before and after operation (P>0.05). It was suggested that CSRBC or whole blood at -80 ℃ could be safely infused to the Rh(D) negative patients without side effects during the surgical operation.

Warm HTK donor pretreatment reduces liver injury during static cold storage in experimental rat liver transplantation

BACKGROUND： Organ shortage has led to an increased number of transplantations from extended criteria donors. These organs are more vulnerable to ischemia-reperfusion injury. Thus, improvement of organ preservation is needed. HTK is a widely used preservation solution for static cold storage in liver transplantation. The present study was to investigate the beneficial effect of warm HTK donor pretreatment on liver preservation.

Using RBF Neural Network for OptimumControl of a Cold Storage

In recent years, advanced control technologies have been used for the optimum control of a cold storage. But there are still a lot of shortcomings. One of the main problems is that the traditional methods can't realize the on-line predictive optimum control of a refrigerating system with simple and valid algorithms. An RBF neural network has a strong ability in nonlinear mapping, a good interpolating value performance, and a higher training speed. Thus a two-stage RBF neural network is proposed in this paper. Combining the measured values with the predicted values, the two-stage RBF neural network is used for the on-line predictive optimum control of the cold storage temperature. The application results of the new methods show a great success.

Nitric Oxide Regulates Mitochondrial Fatty Acids and Promotes CBF Expression of Peach Fruit during Cold Storage

Low-temperature storage is convenient for postharvest preservation of peach fruit,but peach fruit is sensitive to cold damage,which lowers its quality.Nitric oxide(NO)has the potential to improve the bitter resistance of peach fruit.In this work,peach fruit was treated with 15μmol L^(−1)NO and 5μmol L^(−1)c-PTIO[2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxo-3-oxide],to study changes in mitochondrial fatty acids and expression of the C-repeat binding factor(CBF).The results showed that 15μmol L^(−1)exogenous NO significantly maintained fruit quality,reduced peroxidation of mitochondrial fatty acids,increased the activities of the antioxidants superoxide dismutase(SOD),peroxidase(POD),catalase(CAT),ascorbic acid peroxidase(APX),and reduced the content of hydrogen peroxide(H_(2)O_(2)).Meanwhile,NO treatment suppressed the increase in browning index and ion leakage rate,increased the activity of S-nitrosoglutathione reductase(GSNOR),the contents of S-nitrosothiols(SNOs),and the ratios of mitochondrial NAD^(+)/NADH and NADP^(+)/NADPH,increased the expression levels of PpCBF1/5/6.However,the expression levels of PpCBF2/3/4 were not significantly regulated by exogenous NO.Peaches treated with c-PTIO showed opposite effects to those treated with exogenous NO.These results suggest that exogenous NO can improve antioxidant capacity,preserve mitochondrial fatty acids,and upregulate the expression of PpCBF1/5/6 to alleviate cold tolerance and maintain the peach quality during storage.

Influences of Cold Storage at 5℃ for Different Durations on Oviposition of Female Silkworm Moths

In order to investigate the resistance of female silkworm moths to cold storage and their copulation and oviposition after cold storage, copulation and ovipo- sition experiments of Liangguang 2 silkworms and Guican 1 female silkworm moths were conduced under cold storage at 5 ~C for different durations. The results indi- cated that, after cold storage at 5 ~C with relative humidity of 75%, the resistance of female silkworm moths to cold storage varied with different varieties; to be specific, 9-Fu and 7.Xiang, parent silkworm varieties of Liangguang 2 with ancestry of mul- tivoltinism, were relatively resistant to cold storage, and their copulation capability was still at a high level after cold storage for 72 h. Oviposition capability also varied with different varieties and durations; to be specific, under 5 ~C conditions, between two parent silkworm varieties of Liangguang 2, female silkworm moths of 9-Fu achieved the best results within cold storage duration of 24 h, female silkworm moths of 7.Xiang achieved the best results within cold storage duration of 72 h; be- tween two parent silkworm varieties of Guican 1, female silkworm moths of Xinhang achieved the best results without cold storage, female silkworm moths of 826 achieved the best results within cold storage duration of 48 h.

Prospects and Challenges of Utilizing Solar Energy for the COVID-19 Vaccine Cold Storage in Remote Clinics of Tropical Countries:Review

The rapid spread of COVID-19 pandemic has forced several countries in the world to store vaccines in cold storage towards ensuring their protection from being damaged and to maintain their stability.However,most remote clinics,especially those in the equator and islands,are faced with the challenges of hot climates and the inability to afford electricity resources needed to power the cold storage facility.Meanwhile,the hot equatorial region has abundant solar energy to power the vaccine cold storage but previous studies showed that several field workers do not have the ability to maintain the vaccine storage temperature as indicated by the manufacturer’s recommendations.Therefore,this literature review study examines the prospects and challenges of implementing solar-powered cold storage to provide cooling space for remote clinics.This is expected to contribute significantly to cold chain vaccine management technology.The findings showed that four technology integration schemes including Cold Storage Ice Maker,Cold Storage Ice Maker-PCM,Refrigerator-Ice Maker and,Absorbing Cooling-PV-Ice Maker have the potential to be applied in clinics situated in certain tropical regions.

Modeling of seasonal soil cold storage using natural cold energy

To reduce energy consumption on summer air conditioning,a novel seasonal soil cold storage mode using natural energy is presented and two-dimensional transient heat transfer model of U-tube is developed. The three processes of cold storage in winter,shut-down in transition season and cold extraction in summer are simulated by using sensitive heat capacity method with variable time step. The changing of U-tube outlet water temperature in different periods,daily cold storage and cold extraction are estimated. The temperature field of the U-tube and soil around the tube is investigated. Simulations show that seasonal soil cold storage using natural cold energy is feasible in the north to Changchun,which provides theoretical support for seasonal soil cold storage application.

Effects of Cold Storage on Quality Traits of Sardinian Myrtle （Myrtus communis L.） Berries and Their Alcoholic Extracts

Myrtus communis L. is a spontaneous aromatic plant typical of the Mediterranean area. Myrtle berries hydrodistilled products and ethanolic extracts are mainly used as flavouring agents and food supplements. This study evaluated the effect of long-term storage on the quality-related properties of myrtle berries. Storage at 2 ~C for three months effbctively preserved myrtle berries quality, both in the chemical composition and external appearance. No symptoms of chilling injury and decay occurred during the first two months of storage, at the end of storage only the 1.3% of rotting was detected. Total anthocyanic content and anthocyanin glycosides diminished whereas the antioxidant capacity increased in all samples till the end of storage. The antioxidant properties of myrtle berries were not correlated with the anthocyanic fraction. The pH of myrtle berries decreased, while gluconic acid levels increased. The results reported in this paper showed that the storage at 2 ~C for three months appears to be an effective way to preserve myrtle berries quality. The changes in the chemical composition of the fruits subjected to storage had revealed the importance of gluconic acid and pH for myrtle quality assessment. These two parameters can be used as quality markers since a strong relationship has been found between myrtle decay and the changes in these parameters,

Evaluation of myocardial viability during cold storage by measurement of myocardual dielectric properties tanδm in radio frequency

Objective To study the mechanism of myocardial dielectric property changes in radio frequency during hypothermic preservation and explore myocardial viability evaluative method. Methods Hybrid young pigs ( 20 - 30 kg) were used in the experiment. Heart arrest was in-

The influence of aprotinin on the mRNA expression of P-selectin and ICAM-1 in the in situ lung tissue after ischemic cold storage and reperfusion

To explore the influence of aprotinin on the mRNA expression of P-selectin and ICAM-1 in lung tissue after ischemic reperfusion.Methods Thirty New Zealand white rabbits were randomly divided into 3 groups:control group,LPD group and aprotinin group.In situ rabbit lung preservation model was established.In control group,the left lower lung lobe was stored at 10℃ in a specially made lung preservation container for 2 hours and reperfused for another 2 hours.In LPD group and aprotinin group,the left lower lobe was perfused with LPD solution or aprotinin containing LPD solution,respectively,after left lung hilus was clamped.The other procedures were the same as those in control group.The lung tissue was harvested at different time intervals including preclamping lung hilus,2 hours after clamping and 2 hours after reperfusion.The mRNA expression of ICAM-1 and P-selectin in the lung tissue was detected with RT-PCR technique.Results The contents of mRNA of P-selectin at 2 hours after reperfusion in control group and LPD group were significant higher than pre-ischemia and 2 hours after champing the left lung hilus.There was no such significant difference in aprotinin group.The mRNA expression of P-selectin in aprotinin group at 2 hours after reperfusion was significantly lower than that in control group and LPD group.The ICAM-1 mRNA expression at 2 hours after Ischemia and 2 hours after reperfusion in control group and LPD group was significantly higher than the pre-ischemia and its was significantly higher than that in aprotinin group.Conclusion Aprotinin can inhibit the upregulation of the mRNA expression of P selectin and ICAM-1 after ischemia reperfusion in the lung tissue,so the addition of aprotinin in LPD solution may reduce the ischemia reperfusion injury in lung tissue.5 refs,1 tab.

Numerical investigation of a latent cold storage system using shell-and-tube unit

The use of cold thermal storage systems in low-temperature industrial applications is considered one of the most promising ways of improving energy efficiency and reducing the use of power during peak periods.In this study,the thermal performance of a shell-and-tube cold storage system under realistic operating conditions is investigated numerically.The proposed model is developed based on energy balances and then validated using existing experimental data from the literature.Glycol/water is used as the heat transfer fluid(HTF)and the phase transition phenomena in the phase change material(PCM)is simulated using the enthalpy-porosity approach.The influence of several design and operating parameters,including the HTF mass flow rate,HTF temperature,PCM type,and volume,on the cold storage performance during the crystallization process is presented and analyzed.The numerical results show that increasing the HTF mass flow rate accelerates the PCM crystallization process.However,the delivery periods of constant thermal power and constant HTF outlet temperature are reduced.The HTF inlet temperature has a significant effect on the cold storage performance,and the complete charging period is reduced by approximately 37%when the HTF inlet temperature is reduced from−4°C to−7°C.Increasing the number of tubes in the cold storage unit is concluded to significantly improve the thermal performance of the system,and using water/ice as a cold storage medium is more suitable than using the commercial PCMs RT2-HC and RT4-HC.Finally,the proposed numerical model for cold storage systems can be successfully used to design and simulate their realistic operation under different conditions.

Research progress of mobile cold storage using ice slurry

The demand for cooling,such as that of products,spaces,and processes,has increased with the development of urbanization.Cold storage can shift the valley time of electric power to cold energy.Compared to the fixed cold storage routine,mobile cold storage can eliminate site limitations.Ice slurry,as a new functional fluid,has recently become a new source of technology in our social lives.First,the research status of ice slurry mobile cold storage is summarized.Applications in the engineering field,such as space cooling,fisheries,pipeline cleaning,firefighting,and other real scenarios,are listed.Subsequently,key issues are summarized to understand the theoretical basis of ice slurry mobile cold storage,including flow,heat transfer,and loss in the mobile cold storage process-related ice slurry.Both tap water ice slurry and binary ice slurry are distinguished and discussed.Finally,beneficial policy analyses and market prospects for its promotion are presented.In summary,ice slurry mobile cold storage is a popular research topic with broad prospects for energy storage.

Machine perfusion versus cold storage of livers： a meta-analysis

Abstract Different organ preservation methods are key factors influencing the results of fiver transplantation. In this study, the outcomes of experimental models receiving donation after cardiac death （DCD） livers preserved through machine perfusion （MP） or static cold storage （CS） were compared by conducting a meta-analysis. Standardized mean difference （SMD） and 95% confidence interval （CI） were calculated to compare pooled data from two animal species. Twenty-four studies involving MP preservation were included in the meta-analysis. Compared with CS preservation, MP can reduce the levels of aspartate aminotransferase （AST）, alanine aminotransferase （ALT）, lactate dehydrogenase （LDH）, and hyaluronic acid （HA） and the changes in liver weight. By contrast, MP can enhance bile production and portal vein flow （PVF）. Alkaline phosphatase （ALP） levels and histological changes significantly differed between the two preservation methods. In conclusion, MP of DCD livers is superior to CS in experimental animals.

Optimal Design of Grid-Connected Microgrid System for Cold Chain Logistics Centre in China

The growing interest in energy conservation has inspired companies to seek alternatives to highly polluting fuel electricity generation. This study designed an optimised solar wind power generation system to fulfil the energy requirement of a cold chain logistics centre. This study first conducted a thorough analysis of the clarity indicators and daily temperature positions of the cold chain logistics centre, determined the average daily electricity demand, and proposed an effective design scheme. The energy simulation software, RETScreen 8.0, was used to determine the scale of solar photovoltaic and wind power projects that meet the expected energy needs of the cold chain logistics centre. The results indicated that the estimated annual total energy demand was 833689.2 kWh. The annual power generation of 6 kW from solar photovoltaic projects and 150 kW from wind power projects was found to be enough to meet the expected electricity demand. Solar photovoltaic power generation and wind power generation account for 2.44% and 97.56%, respectively. The hybrid energy system achieved a 96.6% reduction in carbon emissions and provides a reasonable payback period of 6.1 years and an electricity generation of 904368.674 kWh per year. The feasibility of the project and the calculated period of investment return are very reasonable. Therefore, this hybrid renewable energy system provides reliable power by combining energy sources.

Numerical Analysis of Doublet Wells for Cold Energy Storage on Heat Damage Treatment in Deep Mines

Deep mining is an inevitable tendency in the development of coal industry. There are many heat damage problems with the increase of mining depth. The technology of using doublet wells, together with Heat Exchange Machine Systems （HEMSs）, to store cold energy is a key to solve the heat damage problems in deep mines. Based on the geological conditions, thermodynamic and hydraulic parameters of Jiahe Mine, the isotherms in the period of cold energy storage and refrigeration and the volumes of cold water within different temperature ranges of the cold energy storage well were numerically analyzed. The results show that 1） with the same pumped and injected water volumes, the lower the temperature of injected water is, the larger the volume.of cold water in the cold energy storage well is. With the larger volume, the effect of cold energy storage is better. 2） the larger the volumes of pumped and reinjected water frigeration is better. And 3） without disturbance, the volume and temperature of cold water in the cold energy storage well can keep unchanged or have only a little change for a long time. Therefore the technology of doublet wells for cold energy storage is feasible and the cold energy storage aquifers can meet the requirement of the technology.

Influence of Sanitization Process on Maintaining Sweet Potato Quality for Export

The whole cold-chain for exporting sweet potato(native variety“Abees”),to foreign market included immediate curing operation directly after harvest helped in healing skin texture,however,in order to reduce postharvest soft rot(Rhizopus stolonifer)incidence following trimming,and washing,ultraviolet light(UV-C)treatment was used as a main sanitizer for eliminating the soft rot.Exposure of the roots to UV-C(254 nm)was applied in a UV-C room on freshly harvested and cured sweet potato while rolling up on a movable line at 20 cm distance for 1,2,and 3 hr.As combining UV-C treatment with chlorine(200 ppm)on roots,marked and significant reduction of the total microbial load and Rhizopus potential was achieved on root surfaces respectively compared with chlorine alone.It also reduced soft rot percentage to almost 0%infection.After 3 months of cold-storage,quality assessment of sweet potato showed that root characteristics were markedly maintained.The ability of UV-C light to induce phenylalanine ammonia lyase(PAL)enzyme activity in root tissue and maintain the activities of peroxidase and polyphenol oxidase,however with slight increase,was detected.UV-C caused an increase of phenol content in sweet potato tissue that made an activation of defense reaction against the rot causal pathogen.As the exposure time to UV-C light increased,a higher content of phenols occurred.Moreover,UV-C application caused decrease in sugar content of root tissue that is flavored by soft rot-causal pathogen.

Liver graft preservation methods during cold ischemia phase and normothermic machine perfusion

The growing demand for donor organs requires measures to expand donor pool.Those include extended criteria donors, such as elderly people, steatotic livers,donation after cardiac death, etc. Static cold storage to reduce metabolic requirements developed by Collins in late 1960 s is the mainstay and the golden standard for donated organ protection. Hypothermic machine perfusion provides dynamic organ preservation at 4°C with protracted infusion of metabolic substrates to the graft during the ex vivo period. It has been used instead of static cold storage or after it as short perfusion in transplant center. Normothermic machine perfusion(NMP) delivers oxygen, and nutrition at physiological temperature mimicking regular environment in order to support cellular function. This would minimize effects of ischemia/reperfusion injury.Potentially, NMP may help to estimate graft functionality before implantation into a recipient. Clinical studies demonstrated at least its non-inferiority or better outcomes vs static cold storage. Regular grafts donated after brain death could be safely preserved with convenient static cold storage. Except for prolonged ischemia time where hypothermic machine perfusion started in transplant center could be estimated to provide possible positive reconditioning effect. Use of hypothermic machine perfusion in regular donation instead of static cold storage or in extended criteria donors requires further investigation. Multicenter randomized clinical trial supposed to be completed in December 2021. Extended criteria donors need additional measures for graft storage and assessment until its implantation. NMP is actively evaluating promising method for this purpose.Future studies are necessary for precise estimation and confirmation to issue clinical practice recommendations.