Search results1 – 10 of over 14000
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…
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.
Purpose – Using elective egg and sperm freezing as a case to compare representations of men and women as agents of biological reproduction, this chapter aims to understand…
Purpose – Using elective egg and sperm freezing as a case to compare representations of men and women as agents of biological reproduction, this chapter aims to understand how gender and risk are co-produced in the context of new reproductive technologies (NRTs).
Methodology – Through a content analysis of newspaper articles published between 1980 and 2016 about egg and sperm freezing, the author traces how fertility risks facing men and women are portrayed in the media.
Findings – Candidates for egg freezing were portrayed in one of the three ways: as cancer patients, career women, or single and waiting for a partner. The ideal users of sperm freezing are depicted in primarily two ways: as cancer patients and as employees in professions with hazardous working conditions. Threats to future fertility for women pursuing careers uninterrupted by pregnancy and child-rearing and women seeking romantic partners are largely portrayed as the result of internal risks. However, threats to future fertility for men working in dangerous professions are largely portrayed as external to them.
Research Limitations – Race and class did not emerge as dominant themes in these data; given the lack of accessibility to NRTs by class and race, this silence must be interrogated by further research.
Value – By comparing the constructions of at-risk groups, the author argues the medicalization of reproduction is gendered as fertility risks portrayed in the media take on a different character between men and women. This research shows how the gendered construction of infertility risk reinforces normative expectations around child-rearing and perpetuates gender inequity in parenting norms.
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…
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…
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.