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This paper aims to study the impacts of groundwater seepage on artificial freezing process of gravel strata, the temperature field characteristics of the strata, and the strata process, closure time and thickness evolution mechanism of the frozen wall.

In this paper several laboratory model tests were conducted, considering different groundwater seepage rate.

The results show that there is a significant coupling effect between the cold diffusion of artificial freezing pipes and groundwater seepage; when there is no seepage, temperature fields upstream and downstream of the gravel strata are symmetrically distributed, and the thickness of the frozen soil column/frozen wall is consistent during artificial freezing; groundwater seepage causes significant asymmetry in the temperature fields upstream and downstream of the gravel strata, and the greater the seepage rate, the more obvious the asymmetry; the frozen wall closure time increases linearly with the increase in the groundwater seepage rate, and specifically, the time length under seepage rate of 5.00 m d⁻¹ is 3.2 times longer than that under no seepage; due to the erosion from groundwater seepage, the thickness of the upstream frozen wall decreases linearly with the seepage velocity, while that of the downstream frozen wall increases linearly, resulting in a saddle-shaped frozen wall.

The research results are beneficial to the optimum design and risk control of artificial freezing process in gravel strata.

The purpose of this paper is to report an experimental study on the effects of various parameters, such as varying flow velocities of water in the pipe, insulating the water pipe, and heating the pipe, to prevent pressurized water in a water hydraulic system from freezing under sub‐zero ambient temperature environment.

An experimental test rig was designed, fabricated, and set up to conduct several experiments to investigate the time taken for water to freeze under sub‐zero ambient temperature at −20°C and with the water initially at a higher temperature than the ambient.

The experiments show that it would take about 90 min for water in the pipe to freeze completely when there is no flow, or water is flowing at slow speed, in the pipe. The results also show that the use of insulation on the pipe would delay the freezing of water inside the pipe; and if used together with heating at several locations on the pipe, freezing of water inside the pipe could be prevented completely.

This paper usefully shows that insulation and heating in a water hydraulic system can prevent freezing of water in the pipe. The promising results of the experimental work mean that water might be able to replace oil in hydraulic systems on aircraft and other low‐temperature applications.

This study purposes to study the influence of artificial freezing on the liquefaction characteristics of Nanjing sand, as well as its mechanism.

was studied through dynamic triaxial tests by means of the GDS dynamic triaxial system on Nanjing sand extensively discovered in the middle and lower reaches of the Yangtze River under seismic load and metro train vibration load, respectively, and potential hazards of the two loads to the freezing construction of Nanjing sand were also identified in the tests.

The results show that under both seismic load and metro train vibration load, freeze-thaw cycles will significantly reduce the stiffness and liquefaction resistance of Nanjing sand, especially in the first freeze-thaw cycle; the more freeze-thaw cycles, the worse structural behaviors of silty-fine sand, and the easier to liquefy; freeze-thaw cycles will increase the sensitivity of Nanjing sand's dynamic pore pressure to dynamic load response; the lower the freezing temperature and the effective confining pressure, the worse the liquefaction resistance of Nanjing sand after freeze-thaw cycles; compared to the metro train vibration load, the seismic load in Nanjing is potentially less dangerous to freezing construction of Nanjing sand.

The research results are helpful to the construction of the artificial ground freezing of the subway crossing passage in the lower reaches of the Yangtze River and to ensure the construction safety of the subway tunnel and its crossing passage.

When new processing technologies are introduced to the food domain, consumer acceptance is one of the key issues for their future success. The purpose of this paper is to study whether consumers are ready to accept a new high pressure freezing method for food processing when different benefits are attached to the processing method.

Consumer attitudes towards high pressure freezing were surveyed in The Netherlands, Belgium, Spain and Finland (n = 936).

Generally, attitudes towards high pressure freezing were neutral, even though the term was unfamiliar for most consumers. When given some information about high pressure freezing technology, consumers considered applying this method as appropriate, especially if it had advantageous consequences to the product. Processing method itself was considered less important than price or environmental impact when the relative importance of choice criteria was studied with conjoint analysis.

Not having to raise the price and possible environmental benefits seem to be the most crucial factors for promoting the acceptance of high pressure freezing as a new processing method in food processing.

The paper shows that advantages of high pressure freezing technology, like decreasing the probability of microbial spoilage or improving the quality of products, had the clearest influence on consumers' appropriateness ratings.

The freezing phenomenon of a falling droplet is a frequently encountered phenomenon in various applications, such as spray crystallization, hail formation and artificial snowmaking. Therefore, this paper aims to understand the freezing processes of a falling droplet without and with initial horizontal velocity in a cold space.

The freezing processes of a falling droplet were characterized using a modified enthalpy-based lattice Boltzmann method.

The temperature field, streamlines and freezing process of the falling droplet were investigated and analyzed. The lower part of the droplet was frozen earlier than the upper part. The freezing trend slowed down in the later stage of the freezing process. The droplet shape was related to the initial vertical velocity, nucleation temperature and initial horizontal velocity.

A modified enthalpy-based lattice Boltzmann method is proposed. In the model, the improved pseudo-potential model is used and the radiation is considered. This method was firstly used to simulate the freezing process of a falling droplet. By examining these freezing processes in detail, the freezing trend and the effect factors of droplet deformation and freezing time were obtained, respectively.

The purpose of this paper is to develop a coupled lattice Boltzmann model for the simulation of the freezing process in unsaturated porous media.

In the developed model, the porous structure with complexity and disorder was generated by using a stochastic growth method, and then the Shan-Chen multiphase model and enthalpy-based phase change model were coupled by introducing a freezing interface force to describe the variation of phase interface. The pore size of porous media in freezing process was considered as an influential factor to phase transition temperature, and the variation of the interfacial force formed with phase change on the interface was described.

The larger porosity (0.2 and 0.8) will enlarge the unfrozen area from 42 mm to 70 mm, and the rest space of porous medium was occupied by the solid particles. The larger specific surface area (0.168 and 0.315) has a more fluctuated volume fraction distribution.

The concept of interfacial force was first introduced in the solid–liquid phase transition to describe the freezing process of frozen soil, enabling the formulation of a distribution equation based on enthalpy to depict the changes in the water film. The increased interfacial force serves to diminish ice formation and effectively absorb air during the freezing process. A greater surface area enhances the ability to counteract liquid migration.

It is of great significance to study the influence of subgrade filling on permafrost temperature field in permafrost area for the smooth construction and safe operation of railway.

The paper builds up the model for the hydrothermal coupling calculation of permafrost using finite element software COMSOL to study how permafrost temperature field changes in the short term after subgrade filling, on which basis it proposes the method of calculation for the concave distortion of freezing front in the subgrade-covered area.

The results show that the freezing front below the subgrade center sinks due to the thermal effect of subgrade filling, which will trigger hydrothermal erosion in case of sufficient moisture inflows, leading to the thawing settlement or the cracking of the subgrade, etc. The heat output of soil will be hindered the most in case of July filling, in which case the sinking and the distortion of the freezing front is found to be the most severe, which the recovery of the permafrost temperature field, the slowest, constituting the most unfavorable working condition. The concave distortion of the freezing front in the subgrade area increases with the increase in temperature difference between the filler and ground surface, the subgrade height, the subgrade width and the volumetric thermal capacity of filler, while decreases with the increase of the thermal conductivity of filler. Therefore, the filler chose for engineering project shall be of small volumetric thermal capacity, low initial temperature and high thermal conductivity whenever possible.

The concave distortion of the freezing front under different working conditions at different times after filling can be calculated using the method proposed.

More than 50 per cent of all German households own a freezing appliance and so far the market of frozen foods is constantly increasing (1 per cent from 2017 to 2018). Despite frozen foods playing an important role in our everyday life, little is known about the consumer’s habits at home. The purpose of this paper is to uncover gaps in the knowledge about consumer behaviour when handling frozen food. Moreover, the impact of consumers on the quality of frozen products should be assessed.

A representative online survey was carried out to investigate different aspects of consumer behaviour concerning frozen foods. Respondents (n=2,053) were questioned about their general handling habits regarding eight different food groups: fruit, vegetables, meat, fish, bread, pastries, ready-to-eat meals and leftovers. The focus was on freezing, pre-handling, packaging and thawing – depending on the age of those questioned and combined with best practice advice regarding quality storage of frozen products.

Most Germans have the opportunity to freeze food and keep their freezers full or medium loaded. Older participants act more efficiently towards quality storage, but more education about freezing and frozen storage would be generally helpful to maintain quality of frozen foods and increase utilisation of freezers, using their full preservation potential.

No open questions were asked due to the scope of more than 2,000 participants, which, in retrospect, would have been instructive.

Consumer handling of frozen food in Germany was investigated in a representative way for the first time, covering age groups from 18 to 69 and household sizes from 1 to >4 people, focussing on eight major food groups.

The purpose of this paper is to critically examine the strengths and weaknesses of a new European Union (EU) initiative attempting an interesting paradigm shift in the field of cross-border asset freezing and confiscation. The entry into force of the Lisbon Treaty and lessons learned from the manifest failure of past EU initiatives (Framework Decisions 2003/577/JHA and 2006/783/JHA) have allowed for such a paradigm shift for the strengthening of mutual recognition of freezing and confiscation orders in the EU.

This paper draws on reports, legal scholarship and other open source data to examine a legislative innovation for the mutual recognition of freezing and confiscation orders in the EU.

The EU legislative initiative that will be examined is innovative in nature and goes beyond international norms on cross-border asset freezing and confiscation. The new initiative needs to be integrated into the broader EU framework that targets criminal proceeds, and at the same time, to be anchored to respect for human rights.

This study examines the strengths and weaknesses of an important new EU initiative, its compatibility with human rights standards and its relationship to international standards of cross-border asset freezing and confiscation.

Numerous problems have arisen in the application of freezing methods to the various types of food products. One problem is concerned with the determination of the direct effects of low temperatures upon the food itself and another problem is to determine the effects of low temperatures upon other factors which may in turn affect the quality of the food. We are especially interested in knowing the exact effects of freezing and other low temperatures upon the micro‐organisms associated with foods. Bacteria constitute the most significant group of micro‐organisms affecting the sanitation and keeping qualities of foods. Those bringing about the decomposition of food products, while they are many and vary greatly, depending upon the nature of the food, are chiefly organisms from the air, water and soil. The types of bacteria found in foods vary greatly in their action on the food and also in reaction or response to varying temperature conditions. The action of micro‐organisms on foods of high carbohydrate content results in fermentations, while the action of the micro‐organisms on foods of high protein content will result, chiefly, in putrefactive changes. The former type of change usually occurs at a more rapid rate, when conditions are favourable, but the latter change usually results in a more undesirable condition of the food. While certain types of bacteria grow best at temperatures well above human body temperatures and others even as low as the freezing point of water, a large majority of those found in foods and the ones normally responsible for the detrimental changes in foods, are active only between 50° and 100° F. It is this latter group which is most implicated in food spoilage and it is significant that this group will be most effectively suppressed by low temperatures. Bacteria are much less affected by low than by high temperatures. Cold alone does not kill most types of bacteria, but slows down their activities to such an extent that they multiply very slowly, if at all. Many bacteria will die off, however, when held at a temperature below that which permits growth and reproduction. Bacteria, generally speaking, will be more easily killed when frozen in pure water than when frozen in foods containing albuminous matter and fats. There are a few bacteria of the cold‐loving type, which may actually multiply and cause slow decomposition at temperatures of 0° C. or less, if substances in solution are present to depress the crystallising point of water. Cold not only retards the growth of bacteria by the direct physiological effect of slowing down the rate of metabolism, but also depresses bacterial activity through its effect on their water and food supplies. Bacteria cannot grow and multiply in a completely frozen or crystallised medium, since they are by nature aquatic and are unable to carry on their normal activities except in a liquid medium. There is no evidence that bacteria maintain a body temperature which would make water available from a completely frozen medium. Bacteria may only utilise food when it is in soluble form, and thus capable of diffusion through their semipermeable cell membranes. When the temperature is sufficiently low to cause the crystallisation of most of the water, the remaining constituents become relatively more concentrated and this will further suppress the activity of the bacterial cells by affecting their osmotic pressures. These effects are very similar to those of partial desiccation or drying. In the course of experimentation some very striking examples of bacterial resistance to low temperatures have been reported. Lactobacillus and aerobacter have been reported to survive in peas stored at −10° C. for two years; whilst bacteria of the genus Pseudomonas were reported to increase in numbers when stored at −4° C. In general it may be said that practically all pathogenic bacteria likely to be found in foods will die off rather rapidly at low temperatures. However, this should not be interpreted to mean that infected foods can be made safe by low temperatures alone. Among the disease producing bacteria transmitted through foods, those of special significance include the organisms and toxins of botulism, typhoid fever, the several organisms of food poisoning called ptomaine poisoning, belonging to the Salmonella group (Salmonella enteritidis, etc.), and various organisms causing infections of the general nature of dysenteries or summer complaints of infants and adults. Frozen foods present no greater threat of botulism than foods preserved by other methods, yet it has been shown that Clostridium botulinum spores may survive freezing at −16° C. for as long as 14 months. The vegetables when thawed become toxic in from three to six days. Experiments have shown that Clostridium botulinum in foods preserved by “quick freezing” and subsequent storage at temperatures below 10° C., show no toxin production for at least 30 days. The lower the temperature of storage the greater the protection against botulism. All foods in which Clostridium botulinum might be present, and which have not been thoroughly heated, should be refrigerated at or near the freezing point. All foods which may harbour the botulism organisms or toxins should be selected with special care, before they are frozen, and care should be taken to see that they are kept frozen until used by the customer. Frozen vegetables should be used immediately after thawing. Thawing and refreezing is always objectionable since such a practice leads to loss of quality, and since bacterial growth and activity may occur during the period of thawing. While the typhoid organisms (Eberthella typhosa) shows considerable variation in resistance to low temperatures, it has been shown that about 99 per cent. will be killed immediately by freezing. Temperatures below freezing apparently have little more effect than the freezing point temperature. Small numbers of the Salmonella and similar organisms of the food poisoning groups may survive in frozen foods for periods of several weeks. It has been shown, however, that no significant growth of activity of these organisms will occur if the foods are refrigerated at 5° C. (41° F.) or less. Moulds and yeasts are of relatively little importance in frozen foods, both from the standpoint of sanitation and food spoilage. While low temperatures will materially retard the rate of enzymatic changes within food products, there is evidence that such changes continue to take place in frozen foods, even considerably below the freezing point. These changes probably account, in part, for the fact that frozen foods once thawed, will decompose more rapidly than foods which have not been frozen.