•Validated CFD model was used to determine the temperatures of the water jet•The water jet cools down when passing the water nozzle•Main heating occurs in the region adjacent to the jet occupied by ...the carrier gas•Ice particles with d ≥ 0.5 mm should be used if water jet is not cooled•Ice particles with d ≥ 0.3 mm can be used if water jet is cooled
Ice abrasive water jet (IAWJ) technology uses ice particles instead of the mineral abrasives used in abrasive water jet (AWJ) technology. Since the thermal conditions are extremely important for the survival of the ice particles and their mechanical properties, the temperatures of the water jet and the adjacent air are analysed for different pressures and temperatures of the water upstream of the water nozzle and different nozzle orifice diameters. The temperature fields are calculated with a fully validated Computational Fluid Dynamic (CFD) model. The results show that the temperature of the jet core does not change significantly, but the adjacent air heats up considerably due to viscous heating; both are influenced by the water temperature and pressure upstream of the water nozzle. A low water temperature upstream of the water nozzle could significantly reduce the expected temperature of the ice particles exiting the cutting head. However, the use of a cold carrier gas such as nitrogen with a temperature of -196°C should not have a significant effect on the temperature of the ice particles inside the cutting head. It is recommended to optimise the geometry of the cutting head to reduce the travel time of the ice inside. If water cooling is not used, the ice particles should have a diameter of more than 0.5 mm. However, if cooling is used, particles as small as 0.3 mm in diameter can be used. The observed temperature conditions play a key role in the further development of IAWJ technology.
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Organic light emitting diodes (OLEDs) have developed to show many advantageous and noticeable properties including their flexibility, easy processing, very cost effective chemical technology, and ...easy combining of organic material, hence having optimized performance is very significant. In this work, in order to enhance OLEDs’ characteristics, we work on the uniformity of indium tin oxide (ITO) as anode, and poly (3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) as Hole Transport Layer by applying argon atmosphere pressure cold jet plasma. We also simulate the device structure (without considering the effect of argon atmosphere pressure cold jet plasma) in order to compare with experimental data. The experimental results show us that having a better uniformity in barriers can lead to decreasing contact angle between ITO, PEDOT:PSS, and Poly2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene (MEH-PPV) layers. This issue leads to better ohmic connection and better injection. When the experimental data are compared with the simulation data, we conclude that by applying 11 min of argon atmosphere pressure cold jet plasma on the ITO layer and 60 s of it on the PEDOT: PSS layer, the experimental data and the simulation results are well matched.
The present research reported the effects of structural properties and immunoreactivity of celiac-toxic peptides and wheat storage proteins modified by cold jet atmospheric pressure (CJAP) plasma. It ...could generate numerous high-energy excited atoms, photons, electrons, and reactive oxygen and nitrogen species, including O
, H
O
, •OH, NO
and NO
etc., to modify two model peptides and wheat storage proteins. The Orbitrap HR-LC-MS/MS was utilized to identify and quantify CJAP plasma-modified model peptide products. Backbone cleavage of QQPFP and PQPQLPY at specific proline and glutamine residues, accompanied by hydroxylation at the aromatic ring of phenylalanine and tyrosine residues, contributed to the reduction and modification of celiac-toxic peptides. Apart from fragmentation, oxidation, and agglomeration states were evaluated, including carbonyl formation and the decline of γ-gliadin. The immunoreactivity of gliadin extract declined over time, demonstrating a significant decrease by 51.95% after 60 min of CJAP plasma treatment in vitro. The CJAP plasma could initiate depolymerization of gluten polymer, thereby reducing the amounts of large-sized polymers. In conclusion, CJAP plasma could be employed as a potential technique in the modification and reduction of celiac-toxic peptides and wheat storage proteins.
This study deals with a unusual cooling event after Typhoon Mujigea passed over the northern South China Sea (SCS) in October 2015. We analyze the satellite sea surface temperature (SST) time series ...from October 3 to 18, 2015 and find that the cooling process in the coastal ocean had two different stages. The first stage occurred immediately after typhoon passage on October 3, and reached a maximum SST drop of −2°C on October 7 as the usual cold wake after typhoon. The second stage or the unusual extended cooling event occurred after 7 d of the typhoon passage, and lasted for 5 d from October 10 to 15. The maximum SST cooling was −4°C and occurred after 12 d of typhoon passage. The mechanism analysis results indicate that after landing and moving northwestward to the Yunnan-Guizhou Plateau (YGP), Typhoon Mujigea (2015) met the westerly wind front on October 5. The low-pressure and positive-vorticity disturbances to the front triggered meridional air flow and low-pressure trough, thus induced a katabatic cold jet downward from the Qinghai-Tibet Plateau (QTP) passing through the YGP to the northwestern SCS. The second cooling reached the maximum SST drop 4 d later after the maximum air temperature drop of −9°C on October 11. The simultaneous air temperature and SST observations at three coastal stations reveal that it is this katabatic cold jet intrusion to lead the unusual SST cooling event.
Irving Langmuir coined the name “plasma” to describe an ionized gas back in 1927. Just over 90 years later, plasma technology is becoming increasingly important in our daily life. For example, in the ...medical field and dentistry, plasma is used as a method of disinfection and sterilization. Moreover, additional potential novel applications of this technology in different forms of therapy have been proposed. In the agricultural sector, plasma technology could contribute to higher crop yields by enhancing seed germination and the growth of plants, as well as the preservation of foods by disinfection. Plasma technology could also be utilized in environmental applications, including water treatment and remediation, as well as treatment of exhaust gases. Although recent extensive studies have uncovered the broad potential of plasma technology, its mechanisms of action remain unclear. Therefore, further studies aimed at elucidating the molecular mechanisms of plasma technology are required. This book is composed of original articles and reviews investigating the molecular mechanisms of plasma biology. Relevant areas of study include applications in plasma medicine, plasma agriculture, as well as plasma chemistry. Studies on potential therapeutic approaches using plasma itself and plasma-treated solutions are also included.
The flow and temperature fields caused by a two-dimensional heating air jet obliquely impinging on a flat plate are experimentally characterized. Whilst the jet flow is discharged at
Re
Dh
=
8.2
×
10
...3 based on the hydraulic diameter of the orifice,
D
h
, and the jet exit-to-plate spacing (separation distance) is fixed at 8
D
h
, the impingement angle (inclination) is systematically decreased from 90° (normal impinging) to 30° (oblique impinging). A separate experiment is carried out for a two-dimensional cooling jet obliquely impinging on a heated plate (constant heat flux). The results demonstrate that the response of local surface temperature to plate inclination behaves in a completely different manner. For impinging jet cooling, the inclination (from normal impinging position) reduces the local effective temperature values at corresponding points about actual stagnation point, inclusive of it. For impinging jet heating, the inclination causes, conversely, an increase in local surface temperature including the stagnation point temperature. However, the shifting of the actual stagnation point towards the uphill side of the plate is consistently observed for both hot and cold jet cases. This newly found feature for an obliquely impinging jet is attributed to the combined effects of asymmetric entrainment and momentum redistribution (i.e., thickening/thinning of hydraulic boundary layers on each side of the plate with respect to the actual stagnation point).
The aerodynamic aspects of indirect thrust measurement by the impulse method have been studied both experimentally and numerically. The underlying basic aerodynamic principle is outlined, the ...phenomena in subsonic, supersonic and arc-heated jets are explored, and factors affecting the accuracy of the method are studied and discussed. Results show that the impulse method is reliable for indirect thrust measurement if certain basic requirements are met, and a simple guideline for its proper application is given.
So-called "cold-jet" propulsion units consist of a piston engine, a blower and the necessary air duct. Till now, all attempts to utilize "cold-jet" propulsion units to maintain the thrust of an ...airplane have been unsuccessful. Analysis has shown that the main difficulty is the deformation of the flow field at the entry to the blower 1.
본 연구는 급성염증과 비슷한 지연성 근육통이 있을 때 초기 한냉치료를 적용함에 있어 냉기에 의한 냉각통증을 최소화하면서, 근육온도를 낮출 수 있는 방법으로 냉기단독과 냉기와 적외선 조사 병용을 적용하여 피부온도에 미치는 영향을 측정하고, 냉기와 적외선 병용치료의 효율성을 평가함과 동시에 초음파를 통한 근 두께를 바탕으로 등척성 근기능을 평가해보고자 ...하였다. 본 연구의 결과 냉기와 적외선 병용치료 시 냉기 단독치료보다 냉각통증의 빈도가 낮게 나타났으며, 냉각통증 자각 시점도 늦게 나타났다. 또한 충분한 냉기적용 후 피부온도가 재가온되는데 있어서 냉기를 2회 적용할 때가 1회 적용할 때 보다 더 느려지며, 냉기 단독치료보다 냉기와 적외선 광선 조사 병용치료 시 더 느려짐을 나타내어 2회 이상의 반복적인 냉기 적용이 냉기의 효용이 있다고 나타났다. 또한 상완이두근 두께 변화에 있어서 병용군이 대조군보다 더 크게 나타나 이 효과를 뒷받침하게 되었다. 이러한 연구결과 자료는 향후 급성염증이 있는 환자에게 한냉치료와 관련된 치료적인 자료로써 활용될 수 있을 것이라 생각되고 근골격계 초음파 진단기를 활용하여 통증에 대한 자각도를 간접적으로 표현하는 것이 구체화되어 임상에서 널리 활용될 것으로 보여진다.
The purpose of this study was to after induced delayed onset muscle soreness, the purpose of this study is to present the effective way on skin temperature changes and cold pain for 14 subjects during to applied with only Cold-jet stream and Cold-jet stream with infra red. 14 healthy men and women who delayed onset muscle soreness eccentric contractions induced by exercise and then the biceps alone was applied to the Cold-jet stream. We measured the time that skin temperature fall from room temperature to 10℃(first period), the time rewarmed from 10℃ to 20℃(second period), the time fall again to 10℃(third period) and the time rewarmed again to 20℃(fourth period). Cold-jet stream with infrared combination therapy was performed with the same method. Results of this study were 1st and 2nd experimental cooling experiments in the to fall to 10℃ Cold-jet stream with infrared combination therapy than in the Cold-jet stream was longer(p<.05). At second period, It took longer in Cold-jet stream with infrared rewarmed than Cold-jet stream to rewarm skin(p<.05). Cold-jet stream with infrared combination therapy than Cold-jet stream had less incidence of cold pain(p<.05). Thickness of biceps brachii were found significant difference related measurment each group was consistent In this study, Cold-jet stream with infrared combination therapy more effective than Cold-jet stream in reduced cold pain and lowering skin temperature. This work was supported by education capacity building project fund of Taegu Science University, 2012.
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