Liquid-Mediated Reversible Thermal Interface for Satellite Thermal Management

Author(s):  
Gilhwan Cha ◽  
Y. Sungtaek Ju

Ability to establish and break thermal contacts in a reversible manner is important in a wide range of applications. These include active thermal conductance control for bolometers [1], pulsed thermoelectric cooling [2], chip scale atomic clocks, and thermal energy harvesting, and thermally reconfigurable networks for satellite thermal management [3]. The last is particularly interesting as it potentially has significant near- as well as long-term technical impact.

2020 ◽  
Vol 142 (8) ◽  
Author(s):  
Makita R. Phillips ◽  
Gregory P. Carman

Abstract The abundance of low-grade waste heat necessitates energy harvesting devices to convert thermal energy to electrical energy. Through magnetic transduction, thermomagnetics can perform this conversion at reasonable efficiencies. Thermomagnetic materials use thermal energy to switch between magnetic and non-magnetic states and convert thermal energy into electrical energy. In this study, we numerically analyzed an active thermomagnetic device for thermal energy harvesting composed of gadolinium (Gd) and neodymium iron boron (NdFeB). A parametric study to determine the device efficiency was conducted by varying the gap distance, heat source temperature, and Gd thickness. Furthermore, the effect of the thermal conductance and applied field was also evaluated. It was found that the relative efficiency for smaller gap distances ranges from ∼15% to 28%; the largest allowable volume of Gd should be used and higher applied field leads to higher efficiencies.


2020 ◽  
Vol 10 (22) ◽  
pp. 7968
Author(s):  
Christoph Rathgeber ◽  
Stefan Hiebler ◽  
Rocío Bayón ◽  
Luisa F. Cabeza ◽  
Gabriel Zsembinszki ◽  
...  

An important prerequisite to select a reliable phase change material (PCM) for thermal energy storage applications is to test it under application conditions. In the case of solid–liquid PCM, a large amount of thermal energy can be stored and released in a small temperature range around the solid–liquid phase transition. Therefore, to test the long-term stability of solid–liquid PCM, they are subjected to melting and solidification processes taking into account the conditions of the intended application. In this work, 18 experimental devices to investigate the long-term stability of PCM are presented. The experiments can be divided into thermal cycling stability tests, tests on PCM with stable supercooling, and tests on the stability of phase change slurries (PCS). In addition to these experiments, appropriate methods to investigate a possible degradation of the PCM are introduced. Considering the diversity of the investigated devices and the wide range of experimental parameters, further work toward a standardization of PCM stability testing is recommended.


Author(s):  
Wei Yu ◽  
◽  
Changqing Liu ◽  
Lin Qiu ◽  
Ping Zhang ◽  
...  

2020 ◽  
pp. 66-73
Author(s):  
A. Simonova ◽  
S. Chudakov ◽  
R. Gorenkov ◽  
V. Egorov ◽  
A. Gostry ◽  
...  

The article summarizes the long-term experience of practical application of domestic breakthrough technologies of preventive personalized medicine for laboratory diagnostics of a wide range of socially significant non-infectious diseases. Conceptual approaches to the formation of an integrated program for early detection and prevention of civilization diseases based on these technologies are given. A vision of the prospects for the development of this area in domestic and foreign medicine has been formed.


Author(s):  
S.V. Borshch ◽  
◽  
R.M. Vil’fand ◽  
D.B. Kiktev ◽  
V.M. Khan ◽  
...  

The paper presents the summary and results of long-term and multi-faceted experience of international scientific and technical cooperation of Hydrometeorological Center of Russia in the field of hydrometeorology and environmental monitoring within the framework of WMO programs, which indicates its high efficiency in performing a wide range of works at a high scientific and technical level. Keywords: World Meteorological Organization, major WMO programs, representatives of Hydrometeorological Center of Russia in WMO


2017 ◽  
Vol 68 (3) ◽  
pp. 599-601
Author(s):  
Dan Paul Stefanescu ◽  
Oana Roxana Chivu ◽  
Claudiu Babis ◽  
Augustin Semenescu ◽  
Alina Gligor

Any economic activity carried out by an organization, can generate a wide range of environmental implications. Particularly important, must be considered the activities that have a significant negative effect on the environment, meaning those which pollute. Being known the harmful effects of pollution on the human health, the paper presents two models of utmost importance, one of the material environment-economy interactions balance and the other of the material flows between environmental factors and socio-economic activities. The study of these models enable specific conditions that must be satisfied for the economic processes friendly coexist to the environment for long term, meaning to have a minimal impact in that the residues resulting from the economic activity of the organization to be as less harmful to the environment.


HortScience ◽  
1997 ◽  
Vol 32 (3) ◽  
pp. 436E-436
Author(s):  
Martin P.N. Gent

The persistence of effects of paclobutrazol or uniconazol on stem elongation was determined for several years after large-leaf Rhododendron and Kalmia latifolia were treated with a single-spray application of these triazol growth-regulator chemicals. Potted plants were treated in the second year from propagation, and transplanted into the field in the following spring. The elongation of stems was measured in the year of application and in the following 2 to 4 years. Treatments with a wide range of doses were applied in 1991, 1992, or 1995. For all except the most-dilute applications, stem elongation was retarded in the year following application. At the highest doses, stem growth was inhibited 2 years following application. The results could be explained by a model of growth regulator action that assumed stem elongation was inversely related to amount of growth regulator applied. The dose response coefficient for paclobutrazol was less than that for uniconazol. The dose that inhibited stem elongation one-half as much as a saturating dose was about 0.5 and 0.05 mg/plant, for paclobutrazol and uniconazol, respectively. The dose response coefficient decreased exponentially with time after application, with an exponential time constant of about 2/year. The model predicted a dose of growth regulator that inhibited 0.9 of stem elongation immediately after application would continue to inhibit 0.5 of stem elongation in the following year.


2019 ◽  
Vol 20 (3) ◽  
pp. 251-264 ◽  
Author(s):  
Yinlu Feng ◽  
Zifei Yin ◽  
Daniel Zhang ◽  
Arun Srivastava ◽  
Chen Ling

The success of gene and cell therapy in clinic during the past two decades as well as our expanding ability to manipulate these biomaterials are leading to new therapeutic options for a wide range of inherited and acquired diseases. Combining conventional therapies with this emerging field is a promising strategy to treat those previously-thought untreatable diseases. Traditional Chinese medicine (TCM) has evolved for thousands of years in China and still plays an important role in human health. As part of the active ingredients of TCM, proteins and peptides have attracted long-term enthusiasm of researchers. More recently, they have been utilized in gene and cell therapy, resulting in promising novel strategies to treat both cancer and non-cancer diseases. This manuscript presents a critical review on this field, accompanied with perspectives on the challenges and new directions for future research in this emerging frontier.


Author(s):  
Ilana Seager ◽  
Douglas S. Mennin ◽  
Amelia Aldao

Generalized anxiety disorder (GAD) is a debilitating condition characterized by excessive, pervasive, uncontrollable, and paralyzing worries about a wide range of future situations. Individuals with this condition frequently find themselves stuck in worry and tension cycles in futile attempts at reducing uncertainty and increasing control. GAD has been associated with substantial impairments in functioning and reduced quality of life. GAD remains poorly understood, and the long-term efficacy and end-state functioning resulting from treatment are weaker compared to other anxiety disorders. Some treatments (e.g., emotion regulation therapy, acceptance-based behavioral therapy) have improved efficacy, partly by targeting emotional dysfunction. Basic psychopathology research has focused on identifying the role of negative affect in GAD, so little is known about how positive affect is experienced and regulated in this disorder. This is particularly important in light of the overlap of this condition with major depressive disorder, which is characterized by low or suppressed positive emotion. Developing such an understanding is essential to further improve the efficacy of emotion-based treatments. This chapter reviews current and future directions in the study of positive affect in GAD. The chapter reviews the nascent research on positive affect and GAD, then illustrates dimensions of future work.


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