272 results on '"Pressure generation"'
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2. Review of State of the Art and Future Options of Hydrogen Storage Systems for Internal Combustion Engines with Direct Fuel Injection for Use in Heavy Duty Vehicles
- Author
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Trott, Richard, Friedrich, Ingo, Bargende, Michael, editor, Reuss, Hans-Christian, editor, and Wagner, Andreas, editor
- Published
- 2021
- Full Text
- View/download PDF
3. An Experimental Investigation of Thermal Runaway and Gas Release of NMC Lithium-Ion Pouch Batteries Depending on the State of Charge Level.
- Author
-
Amano, Kofi Owusu Ansah, Hahn, Sarah-K., Tschirschwitz, Rico, Rappsilber, Tim, and Krause, Ulrich
- Abstract
In this study, 19 experiments were conducted with 25 pouch cells of NMC cathode to investigate thermal runaway and the release of gases from lithium-ion batteries (LIBs). Single cells, double cells, and a four-cell battery stack were forced to undergo thermal runaway inside an air-tight reactor vessel with a volume of 100 dm
3 . The study involved two series of tests with two types of ignition sources. In the Series 1 tests, a heating plug was used to initiate thermal runaway in LIBs in the ranges of 80–89% and 90–100% SOC. In the Series 2 tests, a heating plate was used to trigger thermal runaway in LIBs in the ranges of 30–50%, 80–89%, and 90–100% SOC. Thermal runaway started at an onset temperature of 344 ± 5 K and 345 K for the Series 1 tests and from 393 ± 36 K to 487 ± 10 K for the Series 2 tests. Peak reaction temperatures ranged between 642 K and 1184 K, while the maximum pressures observed were between 1.2 bar and 7.28 bar. Thermal runaway induced explosion of the cells and lead to a rate of temperature increase greater than 10 K/s. The amounts of gases released from the LIBs were calculated from pressures and temperatures measured in the reactor. Then, the gas composition was analyzed using a Fourier transform infrared (FTIR) spectrometer. The highest gaseous production was achieved at a range of 90–100% SOC and higher battery capacities 72 L , 1.8 L / Ah (Series 1, battery stack) and 103 L , 3.2 L / Ah (Series 2, 32 Ah cell)). Among the gases analyzed, the concentration of gaseous emissions such as C2 H4 , CH4 , and C2 H6 increased at a higher cell capacity in both series of tests. The study results revealed characteristic variations of thermal behavior with respect to the type of ignition source used. [ABSTRACT FROM AUTHOR]- Published
- 2022
- Full Text
- View/download PDF
4. A Little Bit of Theory
- Author
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Händle, Frank and Händle, Frank
- Published
- 2019
- Full Text
- View/download PDF
5. New approach for the elucidation of the phenomena involved in the operation of vegetable oil extraction presses.
- Author
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Carré, Patrick
- Subjects
- *
STOKES flow , *VEGETABLE oils , *ECOLOGICAL impact , *COMPRESSIBILITY , *SCREWS , *OILSEEDS - Abstract
In a context where the search for naturalness, the need to reduce the carbon footprint and the development of a decentralized crushing sector are intensifying, mechanical extraction is a technology that is regaining major importance for the industry. The performance of this technique remains far below what is desirable, while the understanding of the main phenomena involved in screw presses remains insufficient. This article, after a brief presentation of the state of the art of this discipline, presents a new model centered on the notions of pressure generation and plasticity. According to this approach, plasticity can account for parameters such as the water and oil content of oilseeds, their temperature, and their possible dehulling. Plasticity in turn would explain both the compressibility of the cake and its ability to resist the thrust of the screws, and consequently to generate pressure or to creep or flow backward depending on the geometry of the screw and the cage. The model must also incorporate the notions of compression velocity, friction, and the complexity of the interactions between these parameters and the impact of the succession of screw segments and cone rings. It has been built on observation and experience and gives an understanding of the need to work simultaneously on the conditioning and geometry of the presses to achieve improved performance in terms of energy, efficiency, and reduction of the temperatures experienced by the proteins and oils [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
6. Short-term exercise affects cardiac function ex vivo partially via changes in calcium channel levels, without influencing hypoxia sensitivity.
- Author
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Uurasmaa, Tytti-Maria, Streng, Tomi, Alkio, Milla, Heinonen, Ilkka, and Anttila, Katja
- Abstract
Exercise is known to improve cardiac recovery following coronary occlusion. However, whether short-term exercise can improve cardiac function and hypoxia tolerance ex vivo independent of reperfusion injury and the possible role of calcium channels in improved hypoxia tolerance remains unknown. Therefore, in the current study, heart function was measured ex vivo using the Langendorff method at different oxygen levels after a 4-week voluntary wheel-running regimen in trained and untrained male mice (C57Bl/6NCrl). The levels of cardiac Ca
2+ -channels: L-type Ca2+ -channel (CACNA1C), ryanodine receptor (RyR-2), sarco(endo)plasmic reticulum Ca2+ -ATPase (SERCA2), and sodium-calcium exchanger were measured using western blot. Trained mice displayed lower cardiac afterload pressure generation capacity (rate and amplitude), but unaltered hypoxia tolerance when compared to untrained mice with similar heart rates. The level of CACNA1C positively correlated with the pressure generation rate and amplitude. Furthermore, the CACNA1C-RYR-2 ratio also positively correlated with the pressure generation rate. While the 4-week training period was not enough to alter the intrinsic cardiac hypoxia tolerance, interestingly it decreased pressure generation capacity and slowed pressure decreasing capacity in the mouse hearts ex vivo. This reduction in pressure generation rate could be linked to the level of channel proteins in sarcolemmal Ca2+ -cycling in trained mice. However, the Ca2+- channel levels did not differ significantly between the groups, and thus, the level of calcium channels cannot fully explain all the functional alterations, despite the detected correlations. Therefore, additional studies are warranted to reveal further mechanisms that contribute to the reduced intrinsic capacity for pressure production in trained mouse hearts. [ABSTRACT FROM AUTHOR]- Published
- 2021
- Full Text
- View/download PDF
7. Contractile function of the excised hagfish heart during anoxia exposure.
- Author
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Gatrell, L. A., Farhat, E., Pyle, W. G., and Gillis, Todd E.
- Subjects
- *
HEART , *HYPOXEMIA , *HEART beat , *ANAEROBIC metabolism - Abstract
Pacific hagfish, Eptatretus stoutii, can recover from 36 h of anoxia and their systemic hearts continue to work throughout the exposure. Recent work demonstrates that glycogen stores are utilized in the E. stoutii heart during anoxia but that these are not sufficient to support the measured rate of ATP production. One metabolic fuel that could supplement glycogen during anoxia is glycerol. This substrate can be derived from lipid stores, stored in the heart, or delivered via the blood. The purpose of this study was to determine the effect of glycerol on the contractile function of the excised E. stoutii heart during anoxia exposure. When excised hearts, perfused with metabolite free saline (mf-saline), were exposed to anoxia for 12 h, there was no difference in heart rate, pressure generation (max-dP), rate of contraction (max-dP/dtsys), or rate of relaxation (max-dP/dtdia) compared to hearts perfused with mf-saline in normoxia. However, hearts perfused with saline containing glycerol (gly-saline) in anoxia had higher max-dP, max-dP/dtsys, and max-dP/dtdia than hearts perfused with mf-saline in anoxia. Tissue levels of glycerol increased when hearts were perfused with gly-saline in normoxia, but not when perfused with gly-saline in anoxia. Anoxia exposure did not affect the activities of triglyceride lipase, glycerol kinase, or glycerol-3-phosphate dehydrogenase. This study suggests that glycerol stimulates cardiac function in the hagfish but that it is not derived from stored lipids. How glycerol may stimulate contraction is not known. This could be as an energy substrate, as an allosteric factor, or a combination of the two. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
8. High-pressure generation in the Kawai-type multianvil apparatus equipped with tungsten-carbide anvils and sintered-diamond anvils, and X-ray observation on CaSnO3 and (Mg,Fe)SiO3.
- Author
-
Yamazaki, Daisuke, Ito, Eiji, Yoshino, Takashi, Tsujino, Noriyoshi, Yoneda, Akira, Gomi, Hitoshi, Vazhakuttiyakam, Jaseem, Sakurai, Moe, Zhang, Youyue, Higo, Yuji, and Tange, Yoshinori
- Subjects
- *
TUNGSTEN carbide , *SINTERING , *DIAMONDS , *X-ray diffraction , *CALCIUM compounds , *HIGH pressure (Technology) - Abstract
We extended the attainable pressure of the Kawai-type multianvil apparatus to 71.3 GPa and 120.3 GPa at room temperature by equipping it with tungsten carbide (WC) and sintered diamond (SD) cubic anvils, respectively. In the experiments with WC anvils, pressure decreased largely, Δ P ∼− 20 GPa, on heating from room temperature to 1500 K. In the experiments with SD anvils, pressure also dropped to 105 GPa from 120 GPa at 1673 K. In order to generate higher pressure and temperatures, therefore, innovation of SD material in both quality and size are essential, together with improvements of cell assembly. Besides pressure generation, we conducted in situ energy-dispersive X-ray diffraction observations on CaSnO 3 and (Mg,Fe)SiO 3 in the experiments with WC and SD anvils, respectively. We observed the growth of new peaks, which can be assigned to the post-perovskite phase, transformed from a starting material of CaSnO 3 perovskite at 48.4 GPa and 1500 K, although they are not clearly identified. In contrast, we could not observe the post-perovskite phase of (Mg,Fe)SiO 3 in the present P–T conditions generated by experiments with SD anvils. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
9. Influence of Pressure Generation Rate on Both Pore Size Distribution Measured by Mercury Porosimetry and Predicted Permeability
- Author
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Osamu Tadai and Wataru Tanikawa
- Subjects
Pore size ,Materials science ,Permeability (electromagnetism) ,Distribution (pharmacology) ,Porosimetry ,Composite material ,Pressure generation - Published
- 2021
- Full Text
- View/download PDF
10. Short-term exercise affects cardiac function ex vivo partially via changes in calcium channel levels, without influencing hypoxia sensitivity
- Author
-
Ilkka Heinonen, Katja Anttila, Tomi Streng, Milla Alkio, and Tytti-Maria Uurasmaa
- Subjects
Cardiac function curve ,Male ,medicine.medical_specialty ,Physiology ,Pressure generation ,RyR ,030204 cardiovascular system & hematology ,Biochemistry ,Sodium-Calcium Exchanger ,Sarcoplasmic Reticulum Calcium-Transporting ATPases ,03 medical and health sciences ,Mice ,0302 clinical medicine ,Afterload ,CACNA ,Internal medicine ,SERCA ,medicine ,Training ,Animals ,Myocytes, Cardiac ,Hypoxia ,030304 developmental biology ,0303 health sciences ,Voltage-dependent calcium channel ,Chemistry ,Ryanodine receptor ,Calcium channel ,Myocardium ,Langendorff ,Ryanodine Receptor Calcium Release Channel ,General Medicine ,Hypoxia (medical) ,Heart function ,medicine.disease ,Ex vivo ,Sarcoplasmic Reticulum ,Endocrinology ,Original Article ,Calcium ,medicine.symptom ,Reperfusion injury ,NCX - Abstract
Exercise is known to improve cardiac recovery following coronary occlusion. However, whether short-term exercise can improve cardiac function and hypoxia tolerance ex vivo independent of reperfusion injury and the possible role of calcium channels in improved hypoxia tolerance remains unknown. Therefore, in the current study, heart function was measured ex vivo using the Langendorff method at different oxygen levels after a 4-week voluntary wheel-running regimen in trained and untrained male mice (C57Bl/6NCrl). The levels of cardiac Ca2+-channels: L-type Ca2+-channel (CACNA1C), ryanodine receptor (RyR-2), sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA2), and sodium-calcium exchanger were measured using western blot. Trained mice displayed lower cardiac afterload pressure generation capacity (rate and amplitude), but unaltered hypoxia tolerance when compared to untrained mice with similar heart rates. The level of CACNA1C positively correlated with the pressure generation rate and amplitude. Furthermore, the CACNA1C-RYR-2 ratio also positively correlated with the pressure generation rate. While the 4-week training period was not enough to alter the intrinsic cardiac hypoxia tolerance, interestingly it decreased pressure generation capacity and slowed pressure decreasing capacity in the mouse hearts ex vivo. This reduction in pressure generation rate could be linked to the level of channel proteins in sarcolemmal Ca2+-cycling in trained mice. However, the Ca2+-channel levels did not differ significantly between the groups, and thus, the level of calcium channels cannot fully explain all the functional alterations, despite the detected correlations. Therefore, additional studies are warranted to reveal further mechanisms that contribute to the reduced intrinsic capacity for pressure production in trained mouse hearts.
- Published
- 2021
11. An Experimental Investigation of Thermal Runaway and Gas Release of NMC Lithium-Ion Pouch Batteries Depending on the State of Charge Level
- Author
-
Kofi Owusu Ansah Amano, Sarah-K. Hahn, Rico Tschirschwitz, Tim Rappsilber, and Ulrich Krause
- Subjects
Electrochemistry ,Energy Engineering and Power Technology ,Electrical and Electronic Engineering ,lithium-ion batteries ,battery ,pouch cell ,NMC cathode ,thermal runaway ,gas release ,reaction gas analysis ,pressure generation - Abstract
In this study, 19 experiments were conducted with 25 pouch cells of NMC cathode to investigate thermal runaway and the release of gases from lithium-ion batteries (LIBs). Single cells, double cells, and a four-cell battery stack were forced to undergo thermal runaway inside an air-tight reactor vessel with a volume of 100 dm3. The study involved two series of tests with two types of ignition sources. In the Series 1 tests, a heating plug was used to initiate thermal runaway in LIBs in the ranges of 80–89% and 90–100% SOC. In the Series 2 tests, a heating plate was used to trigger thermal runaway in LIBs in the ranges of 30–50%, 80–89%, and 90–100% SOC. Thermal runaway started at an onset temperature of 344 ± 5 K and 345 K for the Series 1 tests and from 393 ± 36 K to 487 ± 10 K for the Series 2 tests. Peak reaction temperatures ranged between 642 K and 1184 K, while the maximum pressures observed were between 1.2 bar and 7.28 bar. Thermal runaway induced explosion of the cells and lead to a rate of temperature increase greater than 10 K/s. The amounts of gases released from the LIBs were calculated from pressures and temperatures measured in the reactor. Then, the gas composition was analyzed using a Fourier transform infrared (FTIR) spectrometer. The highest gaseous production was achieved at a range of 90–100% SOC and higher battery capacities 72L, 1.8 L/Ah (Series 1, battery stack) and 103L, 3.2 L/Ah (Series 2, 32 Ah cell)). Among the gases analyzed, the concentration of gaseous emissions such as C2H4, CH4, and C2H6 increased at a higher cell capacity in both series of tests. The study results revealed characteristic variations of thermal behavior with respect to the type of ignition source used.
- Published
- 2022
- Full Text
- View/download PDF
12. Expiratory muscle strength training improves measures of pressure generation and cough strength in a patient with myotonic dystrophy type 1
- Author
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Donna Banks, Jodi Allen, Christina H. Smith, Chris Turner, and Ronan Astin
- Subjects
0301 basic medicine ,Expiratory Muscle Strength Training ,Myotonic dystrophy ,03 medical and health sciences ,0302 clinical medicine ,Swallowing ,medicine ,Respiratory function ,Expiratory muscle ,Genetics (clinical) ,business.industry ,respiratory system ,medicine.disease ,Dysphagia ,respiratory tract diseases ,030104 developmental biology ,Neurology ,Anesthesia ,Mouth pressure ,Pediatrics, Perinatology and Child Health ,Neurology (clinical) ,medicine.symptom ,business ,030217 neurology & neurosurgery ,Pressure generation ,circulatory and respiratory physiology - Abstract
Expiratory muscle strength training (EMST) exercise programmes aim to improve respiratory function by increasing the force generating capability of expiratory muscles by resistance training. In neuromuscular conditions, in which cough flow generation is often decreased, there is increasing interest in EMST as a therapeutic intervention. We present data showing efficacy of EMST in a patient with adult onset Myotonic Dystrophy Type 1 (DM1). A domiciliary training programme (5 days per week over 32 weeks) resulted in increases in maximum expiratory mouth pressure (from 15 cmH2O to 38 cmH2O) and peak cough flow (300 L/min to 390 L/min). Improvements were also seen in maximum inspiratory mouth pressure (26 cmH2O to 52 cmH2O) and sniff nasal inspiratory pressure (40 cmH2O to 69 cmH2O). No changes were detected in speech or swallowing. This novel study demonstrates that cough flow generation in DM1 may be increased by a programme of expiratory muscle training. A clinical trial of EMST in DM1 is warranted.
- Published
- 2020
- Full Text
- View/download PDF
13. Pressure generation in the Kawai-type multianvil apparatus and rheology of the Earth's interior
- Author
-
Daisuke Yamazaki
- Subjects
Grain growth ,Viscosity ,Materials science ,Rheology ,Geochemistry and Petrology ,Inner core ,Thermodynamics ,Economic Geology ,Pressure generation ,Earth (classical element) - Published
- 2020
- Full Text
- View/download PDF
14. New approach for the elucidation of the phenomena involved in the operation of vegetable oil extraction presses☆
- Author
-
Patrick Carré
- Subjects
pressure generation ,Oils, fats, and waxes ,unidirectional pressing ,plasticity ,compressibility ,screw geometry ,TP670-699 ,Agronomy and Crop Science ,Biochemistry ,Food Science - Abstract
In a context where the search for naturalness, the need to reduce the carbon footprint and the development of a decentralized crushing sector are intensifying, mechanical extraction is a technology that is regaining major importance for the industry. The performance of this technique remains far below what is desirable, while the understanding of the main phenomena involved in screw presses remains insufficient. This article, after a brief presentation of the state of the art of this discipline, presents a new model centered on the notions of pressure generation and plasticity. According to this approach, plasticity can account for parameters such as the water and oil content of oilseeds, their temperature, and their possible dehulling. Plasticity in turn would explain both the compressibility of the cake and its ability to resist the thrust of the screws, and consequently to generate pressure or to creep or flow backward depending on the geometry of the screw and the cage. The model must also incorporate the notions of compression velocity, friction, and the complexity of the interactions between these parameters and the impact of the succession of screw segments and cone rings. It has been built on observation and experience and gives an understanding of the need to work simultaneously on the conditioning and geometry of the presses to achieve improved performance in terms of energy, efficiency, and reduction of the temperatures experienced by the proteins and oils
- Published
- 2022
15. Magnetically-Induced Pressure Generation in Magnetorheological Fluids under the Influence of Magnetic Fields
- Author
-
Ubaidillah Ubaidillah, Fitrian Imaduddin, Purwadi Joko Widodo, and Eko Prasetya Budiana
- Subjects
Technology ,Materials science ,QH301-705.5 ,QC1-999 ,Finite element simulation ,pressure ,magnetic fileds ,General Materials Science ,Tube (fluid conveyance) ,magnetorheological fluids ,Biology (General) ,Instrumentation ,QD1-999 ,Fluid Flow and Transfer Processes ,Process Chemistry and Technology ,Physics ,U-shaped tube ,General Engineering ,Magnetic field effect ,Mechanics ,Engineering (General). Civil engineering (General) ,Computer Science Applications ,Magnetic field ,Chemistry ,Electromagnetic coil ,Magnetorheological fluid ,Current (fluid) ,TA1-2040 ,Pressure generation - Abstract
This study aims to observe the magnitude of the Magnetorheological Fluids (MRFs) pressure due to the application of a magnetic field. This was accomplished by placing the MRFs in a U-shaped tube, then applying a magnetic field generated by a magnetic coil. A finite element simulation for the magnetic field was carried out to estimate the magnetic field strength generated by the coil variable to the current input given in the simulated apparatus. Changes in MRFs pressure were recorded using a data logger to better observe the fluid pressure phenomena occurring in the MRFs with respect to current input variations. The results showed that the magnetic field influences the MRFs fluid pressure proportionally. The slope is not constant as the magnetic field effect to the fluid pressure gets stronger when the current input is higher. However, there are also an adverse effect of heat generated in the coil in higher current, which results in coil performance degradation and reduces the magnetic field strength.
- Published
- 2021
16. The long-lasting cardiac action potentials are related to pressure generation in the heart
- Author
-
José Guilherme Chaui-Berlinck and Vitor Rodrigues da Silva
- Subjects
Long lasting ,medicine.medical_specialty ,business.industry ,Internal medicine ,General Engineering ,medicine ,Cardiology ,Cardiac action potential ,business ,Pressure generation - Published
- 2021
- Full Text
- View/download PDF
17. Spatial and temporal changes in buccal pressure during prey-capture in the trumpetfish (Aulostomus maculatus)
- Author
-
Samuel Tegge, Steve Huskey, and Jason Hall
- Subjects
0106 biological sciences ,Water resistance ,Trumpetfish ,Peak pressure ,010607 zoology ,Prey capture ,Buccal administration ,Anatomy ,Biology ,biology.organism_classification ,010603 evolutionary biology ,01 natural sciences ,Pressure sensor ,Elongated skull ,stomatognathic system ,Animal Science and Zoology ,Pressure generation ,Developmental Biology - Abstract
Suction feeding involves the coordinated contraction of numerous muscles to rapidly expand the buccal cavity to create hydrodynamic loading. The expanding buccal cavity generates forces that draw water and the prey item in as the pressure is equalized between the buccal cavity and the external environment. Here we quantified the spatial and temporal aspects of subambient pressure generation in the elongated buccal cavity of trumpetfish (Aulostomus maculatus) during feeding strikes. Pressure was measured with two Millar micro-tip catheter pressure transducers (SPR-407) and was synchronized with high-speed videography. There was a statistically significant difference (p = 0.03) between the mean pressure generated in the caudal buccal cavity (− 24.67 ± 0.72 kPa) and the rostral buccal cavity (− 18.69 ± 0.66 kPa). There was also a statistically significant difference (p = 0.01) in the time between rostral and caudal peak pressure generation. The caudal peak pressure is generated 5.56 ± 0.38 ms before the rostral peak pressure and is nearly synchronous with maximum hyoid depression. Kinematic data reveal that, after subambient pressure is generated by hyoid depression, the buccal cavity first expands laterally at the mouth opening and proceeds in a caudal direction. Morphological data suggest that trumpetfish evolved lengthened sesamoid tendons that translate whole-body contractile forces to cranial elevation and buccal cavity expansion during feeding. These tendons may have evolved to compensate for the lengthy moment arm created by the elongated skull of trumpetfish in order to overcome the resultant increased water resistance.
- Published
- 2019
- Full Text
- View/download PDF
18. High-pressure generation in the Kawai-type multianvil apparatus equipped with tungsten-carbide anvils and sintered-diamond anvils, and X-ray observation on CaSnO3 and (Mg,Fe)SiO3
- Author
-
Jaseem Vazhakuttiyakam, Hitoshi Gomi, Noriyoshi Tsujino, Eiji Ito, Yoshinori Tange, Yuji Higo, Moe Sakurai, Daisuke Yamazaki, Takashi Yoshino, Akira Yoneda, and Youyue Zhang
- Subjects
Diffraction ,Global and Planetary Change ,Materials science ,010504 meteorology & atmospheric sciences ,Post-perovskite ,X-ray ,Analytical chemistry ,Diamond ,engineering.material ,010502 geochemistry & geophysics ,01 natural sciences ,chemistry.chemical_compound ,chemistry ,Tungsten carbide ,Phase (matter) ,engineering ,General Earth and Planetary Sciences ,Pressure generation ,0105 earth and related environmental sciences ,Perovskite (structure) - Abstract
We extended the attainable pressure of the Kawai-type multianvil apparatus to 71.3 GPa and 120.3 GPa at room temperature by equipping it with tungsten carbide (WC) and sintered diamond (SD) cubic anvils, respectively. In the experiments with WC anvils, pressure decreased largely, ΔP ∼−20 GPa, on heating from room temperature to 1500 K. In the experiments with SD anvils, pressure also dropped to 105 GPa from 120 GPa at 1673 K. In order to generate higher pressure and temperatures, therefore, innovation of SD material in both quality and size are essential, together with improvements of cell assembly. Besides pressure generation, we conducted in situ energy-dispersive X-ray diffraction observations on CaSnO3 and (Mg,Fe)SiO3 in the experiments with WC and SD anvils, respectively. We observed the growth of new peaks, which can be assigned to the post-perovskite phase, transformed from a starting material of CaSnO3 perovskite at 48.4 GPa and 1500 K, although they are not clearly identified. In contrast, we could not observe the post-perovskite phase of (Mg,Fe)SiO3 in the present P–T conditions generated by experiments with SD anvils.
- Published
- 2019
- Full Text
- View/download PDF
19. A unified morphological scenario for the evolution of haemolymph pressure generation in spiders (Araneae: Arachnida)
- Author
-
Jens Runge and Christian S. Wirkner
- Subjects
Hemolymph ,Zoology ,Animal Science and Zoology ,Biology ,Ecology, Evolution, Behavior and Systematics ,Pressure generation - Published
- 2019
- Full Text
- View/download PDF
20. Permanent densification of silica glass for pressure calibration between 9 and 20 GPa at ambient temperature
- Author
-
Timothy A. Strobel, Yingwei Fei, Alexandra Poltorak, and Michael Guerette
- Subjects
Materials science ,Silica glass ,Diamond ,engineering.material ,010502 geochemistry & geophysics ,Condensed Matter Physics ,01 natural sciences ,symbols.namesake ,Dimple ,0103 physical sciences ,Calibration ,symbols ,engineering ,Composite material ,010306 general physics ,Raman spectroscopy ,Pressure generation ,0105 earth and related environmental sciences - Abstract
Permanent density increase of silica glass was used to calibrate pressure generation delivered by cupped sintered diamond anvils (‘dimple anvils’) [Haberl B, Molaison JJ, Neuefeind JC, et al. Simpl...
- Published
- 2019
- Full Text
- View/download PDF
21. Analysis of Annular Pressure Generation Mechanism and Research on Safety Evaluation
- Author
-
Qilun Liu, Wei Rong, Liangwen Liu, Xu Zhang, Yingying Zhang, Xixi Chen, and Weiyi Xie
- Subjects
Petroleum engineering ,0211 other engineering and technologies ,02 engineering and technology ,010501 environmental sciences ,01 natural sciences ,Mechanism (engineering) ,Environmental sciences ,Temperature and pressure ,Sulfur content ,Capacity utilization ,Environmental science ,GE1-350 ,021108 energy ,Zoning ,Gas consumption ,Pressure generation ,0105 earth and related environmental sciences - Abstract
With the rapid increase of seasonal heating gas consumption in winter in the Beijing-Tianjin-Hebei region, the existing gas storage scale and injection and production well network in the central Hebei region can hardly meet the demand of storage capacity utilization and gas recovery. Therefore, the effective utilization of old Wells has become the goal of gas storage construction. However, the old Wells that have been put back into production are mostly converted from depleted reservoirs, which have different degrees of annular pressure problems. Through investigation and investigation, it is found that there are many factors causing annular zoning pressure. By analyzing the properties of Wells with high sulfur content and high temperature and pressure, this paper studies the mechanism of causing annular zoning pressure, and puts forward the safety management method, so as to make the safety evaluation of annular zoning pressure more comprehensive.
- Published
- 2021
22. Over 1Mbar generation in the Kawai-type multianvil apparatus and its application to compression of (Mg0.92Fe0.08)SiO3 perovskite and stishovite.
- Author
-
Yamazaki, D., Ito, E., Yoshino, T., Tsujino, N., Yoneda, A., Guo, X., Xu, F., Higo, Y., and Funakoshi, K.
- Subjects
- *
PEROVSKITE , *HIGH pressure (Science) , *SILICA , *CALCIUM chloride , *PHASE transitions - Abstract
Highlights: [•] Pressure was generated up to 109.3GPa in a Kawai-type multianvil apparatus. [•] K T0 and were determined to be 268GPa and 3.8, respectively, for perovskite. [•] Stishovite transforms to the CaCl2-type phase at ∼54GPa at 300K. [Copyright &y& Elsevier]
- Published
- 2014
- Full Text
- View/download PDF
23. Novel Condensate Removal with in-Situ Pressure Generation Via Thermochemical Fluids in Different Sandstone Formations
- Author
-
Amjed Hassan, Ayman Al-Nakhli, Mohammed Bataweel, Abdulaziz Al-Majed, and Mohamed Mahmoud
- Subjects
In situ ,020401 chemical engineering ,Chemical engineering ,020209 energy ,0202 electrical engineering, electronic engineering, information engineering ,Environmental science ,02 engineering and technology ,0204 chemical engineering ,Pressure generation - Abstract
With the increasing demand on gas worldwide, condensate banking represents a challenging problem in tight reservoirs and can significantly impair the production rate. Gas injection and water-altering gas are the common techniques used to avoid the condensate development by maintaining the reservoir pressure above the dew point curve. However, these treatments are associated with high operational costs and large initial investment, also they are considered as temporary methods. This study presents a chemical treatment for permanent removal of condensate banking using thermochemical fluids. Chemicals are injected to react downhole and generate in-situ pressure and heat. High pressure will raise the gas pressure above the dew point, and the generated heat will change the phase of liquid condensate to gas. The effectiveness of thermochemical treatment in mitigating the condensate damage in different types of sandstone rocks is presented. The effect of mineralogical composition on the condensate removal was investigated. Also, the impact of clay content on the efficiency of thermochemical treatment was investigated. Results showed that thermochemical treatment is an effective method for removing the condensate damage from different types of sandstone formations. Condensate removal of more than 60% was achieved using Huff and Puff injection mode. Good correlation between the rock permeability and the condensate removal efficiency was observed. Higher condensate removal was obtained for the rock samples of high permeability values. Moreover, the presence of sensititve clay minerals in the treated rock showed miner correlation on the effectiveness of condensate removal, which indicates that the injected chemicals are able to stabilize the clay minerals and avoid clay damage. No clay swelling or particle migration was induced during the thermochemical treatment, since no permeability reduction was observed for all samples. Instead, the treated samples showed higher permeability values after the injection of thermochemical fluids. In addition, the profiles of condensate removal indicate that three cycles of thermochemical injection are sufficient for mitigating the condensate banking, and small condensate removal can be achieved during the late cycles of Huff and Puff operation. This paper shows that thermo-chemical treatment can remove more than 60% of the condensate damage for different types of tight sandstones. Huff and Puff treatment was found to be very practical to remediate the condensate banking from different sandstone rocks. Also, this work confirms that thermo-chemical treatment can be applied in the formation with sensitive clays for removing the condensate banking without affecting the clay stability or inducing clay damage.
- Published
- 2020
- Full Text
- View/download PDF
24. Integrated long-term multifunctional pediatric mechanical circulatory assist device
- Author
-
Joseph W. Rossano, Harutyun Sarkisyan, Randy Stevens, Amy L. Throckmorton, and Vakhtang Tchantchaleishvili
- Subjects
Iterative design ,Computer science ,medicine.medical_treatment ,0206 medical engineering ,Biomedical Engineering ,Medicine (miscellaneous) ,Bioengineering ,02 engineering and technology ,030204 cardiovascular system & hematology ,Prosthesis Design ,Article ,Biomaterials ,03 medical and health sciences ,Impeller ,0302 clinical medicine ,medicine ,Humans ,Child ,Simulation ,Heart Failure ,Scalar (physics) ,Experimental data ,General Medicine ,020601 biomedical engineering ,Blood pump ,Ventricular assist device ,Blood damage ,Computer-Aided Design ,Heart-Assist Devices ,Pressure generation - Abstract
There continues to be limited, viable ventricular assist device technology options to support the dysfunctional states of pediatric heart failure. To address this need, we are developing a magnetically suspended, versatile pumping technology that uniquely integrates two blood pumps in a series configuration within a single device housing. This device enables operational switching from the usage of one pump to another as needed for clinical management or to support growth and development of the pediatric patient. Here, we present the initial design where we conducted a virtual fit study, the Taguchi Design Optimization Method, iterative design to develop pump geometries. Computational tools were used to estimate the pressure generation, capacity delivery, hydraulic efficiency, fluid stress levels, exposure time to stresses, blood damage index, and fluid forces on the impellers. Prototypes of the pumps were tested in a flow loop using a water-glycerin solution. Both designs demonstrated the capability to generate target pressures and flows. Blood damage estimations were below threshold levels and achieved design requirements; however, maximum scalar stress levels were above the target limit. Radial and axial forces were less than 1 N and 10 N, respectively. The performance data trends for physical prototypes correlated with theoretical expectations. The centrifugal prototype was able to generate slightly higher pressure rises than numerical predictions. In contrast, the axial prototype outperformed the computational studies. Experimental data were both repeatable and reproducible. The findings from this research are promising, and development will continue.
- Published
- 2020
25. Measurement of Simulated Debris Removal Rates in an Artificial Root Canal to Optimize Laser-Activated Irrigation Parameters
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Matija Jezeršek, Nejc Lukač, and Matjaž Lukač
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Materials science ,Root canal ,Dermatology ,Lasers, Solid-State ,01 natural sciences ,law.invention ,010309 optics ,030207 dermatology & venereal diseases ,03 medical and health sciences ,0302 clinical medicine ,Optics ,Basic Science ,law ,0103 physical sciences ,medicine ,Therapeutic Irrigation ,laser‐activated irrigation ,root canal irrigation ,Root Canal Irrigants ,Pulse (signal processing) ,business.industry ,Laser ,Debris ,Root Canal Therapy ,medicine.anatomical_structure ,Flushing ,Laser activated irrigation ,Surgery ,medicine.symptom ,Dental Pulp Cavity ,business ,Er:YAG laser ,Pressure generation ,Root Canal Preparation - Abstract
Background and objectives To compare temporal rates of debris removal from an artificial root canal for three laser-assisted irrigation modalities single-pulse super short pulse (SSP), and two dual-pulse X-SWEEPS and AutoSWEEPS, and for two fiber-tip (FT) geometries flat and radial, and to evaluate the dependence of the debris flushing rate on the delay between the SWEEPS laser pulse pair. Study design/materials and methods Laser-assisted irrigation was performed with a pulsed Er:YAG laser operating in single-pulse SSP and dual-pulse SWEEPS laser modalities. The laser energy was delivered to the water-filled model access cavity through a FT with either a flat or radial ending. The X-SWEEPS modality delivered pairs of laser pulses separated by a fixed adjustable delay, while with the AutoSWEEPS modality the delay was automatically and repeatedly swept between 200 and 600 microseconds. The debris removal rate was determined with the use of a digital camera by measuring the rate at which a simulated debris was being flushed out of the artificial root canal. Results The simulated debris removal rate of the AutoSWEEPS modality is almost three times higher compared with that of the SSP modality. Further, the flat FT outperforms the radial FT by a factor of more than five in the case of SSP, and by more than 10 with AutoSWEEPS. The X-SWEEPS flushing rate exhibits strong dependence on the delay between the SWEEPS pulse pair, with the highest removal rate measured to be more than seven times higher in comparison with SSP. Conclusion Dual-pulse laser irrigation modalities (AutoSWEEPS and X-SWEEPS) exhibit significantly higher simulated debris removal rates in comparison with the standard single-pulse SSP laser-assisted irrigation. As opposed to the previously reported dependence of pressure generation on FT geometry, the flat FT's simulated debris removal rate significantly outperforms the radial FT. © 2020 The Authors. Lasers in Surgery and Medicine published by Wiley Periodicals LLC.
- Published
- 2020
26. Developments of nano-polycrystalline diamond anvil cells for neutron diffraction experiments
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Keishiro Yamashita, Shinichi Machida, Takanori Hattori, Tetsuo Irifune, Asami Sano-Furukawa, Satoshi Nakano, Kazuki Komatsu, Stefan Klotz, The University of Tokyo, Institut de minéralogie, de physique des matériaux et de cosmochimie (IMPMC), Muséum national d'Histoire naturelle (MNHN)-Institut de recherche pour le développement [IRD] : UR206-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), National Institute for Materials Science (NIMS), Comprehensive Research Organization for Science and Society (CROSS), Japan Atom Energy Agcy, J PARC Ctr, 2-4 Shirakata, Tokai, Ibaraki 3191195, Japan, Japan Atomic Energy Agency, Japanese National Observatory, Ehime University [Matsuyama], The University of Tokyo (UTokyo), and Ehime University [Matsuyama, Japon]
- Subjects
[PHYS]Physics [physics] ,Materials science ,business.industry ,Neutron diffraction ,technology, industry, and agriculture ,nano-polycrystalline diamond ,High pressure cell ,Cell design ,010502 geochemistry & geophysics ,Condensed Matter Physics ,01 natural sciences ,Polycrystalline diamond ,high pressure ,neutron diffraction ,High pressure ,biological sciences ,0103 physical sciences ,Nano ,Optoelectronics ,010306 general physics ,business ,Pressure generation ,0105 earth and related environmental sciences - Abstract
International audience; Developments of nano-polycrystalline diamond anvil cells for neutron diffraction experiments A new high-pressure cell for neutron diffraction experiments using nano-polycrystalline anvils is presented. The cell design, off-line pressure generation tests and a gas-loading procedure for this cell are described. The performance is illustrated by powder neutron diffraction patterns of ice VII to ~82 GPa. We also demonstrate the feasibility of single crystal neutron diffraction experiments of Fe3O4 at ambient conditions using this cell and discuss the current limitation and future developments.
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- 2020
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27. The mechanics of urethral closure, incontinence and midurethral sling repair. Part 2 further experimental validation (1993‐2003)
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Peter Petros and Burghard Abendstein
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Stress incontinence ,Sling (implant) ,Urethral closure ,Urinary Incontinence, Stress ,Urology ,030232 urology & nephrology ,03 medical and health sciences ,0302 clinical medicine ,Urethra ,medicine ,Humans ,Suburethral Slings ,Ligaments ,030219 obstetrics & reproductive medicine ,business.industry ,Experimental validation ,Anatomy ,Insertion point ,medicine.disease ,medicine.anatomical_structure ,Urologic Surgical Procedures ,Female ,Pubovesical ligament ,Rhabdosphincter ,Neurology (clinical) ,business ,Pressure generation - Abstract
IN: Part 1, The original 1990 science behind the MUS, the hypothesized closure mechanisms, and the prototype MUS itself were presented. The next phase of MUS development began in 1990 in collaboration with the late Ulf Ulmsten. It had two arms Further development of the prototype MUS. Further anatomical, imaging, urodynamic studies to validate the role of PUL in the closure mechanisms. A second series of prototype MUS operations performed under LA/sedation resulted in a permanently implanted polypropylene sling and the MUS as is known today. The tape was elevated until no urine leaked on coughing. This demonstrated that the artificial PUL neoligament needed to be at a specific length to work. Anatomical, EMG and video ultrasound, and X-ray studies confirmed three directional muscles contracted pubourethral (PUL) and uterosacral (USL) ligaments. The contribution of the horseshoe shaped rhabdosphincter (RS) to continence was directly tested with pressure measurements under live surgery conditions. It was concluded that the RS was responsible for pressure generation but not continence. Continence was a consequence of intraurethral resistance to flow created by the distal and proximal urethral closure mechanisms, both governed ultimately by the Law of Poiseuille. CONCLUSIONS: The key element in curing USI is creation of a competent PUL using the collagenous neoligament surgical principle described in Part 1. This creates a firm insertion point for the three directional muscle forces, restoring their contractile strength and closure.
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- 2018
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28. A modified, hydrophobic soundless cracking demolition agent for non-explosive demolition and fracturing applications
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Bisheng Wu, Tharaka Dilanka Rathnaweera, V.R.S. De Silva, Mandadige Samintha Anne Perera, and Pathegama Gamage Ranjith
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Environmental Engineering ,Materials science ,Explosive material ,General Chemical Engineering ,0211 other engineering and technologies ,Delayed onset ,02 engineering and technology ,Welan gum ,021001 nanoscience & nanotechnology ,Cracking ,chemistry.chemical_compound ,Compressive strength ,chemistry ,021105 building & construction ,Demolition ,Environmental Chemistry ,Composite material ,0210 nano-technology ,Safety, Risk, Reliability and Quality ,Expansive ,Pressure generation - Abstract
Soundless Cracking Demolition Agents (SCDAs) are an alternative to the current practices of environmentally detrimental conventional demolition and rock fragmentation methods Although having the potential to produce a dense network of fractures when injected into a borehole, the applicability of SCDA is limited by its susceptibility to dilution in water-saturated conditions and delayed onset of expansive pressure. Such limitations can be eliminated by introducing a Viscousity Enhancing Agent (VEA) to modify the SCDA system. Even though adding a VEA enhances the wash out resistance in the SCDA system, the associated delay in the onset of expansive pressure limits the application of this new technology in the industry. Therefore, this study aims to recover the delayed onset of expansive pressure in modified SCDA by utilising a chemical accelerator (CaCl2) through a comprehensive experimental study. The developed new material was fully characterised by performing mechanical tests (uniaxial compressive strength tests, flowability tests, washout resistance tests), microstructural analysis (scanning electron microscopy) and mineralogical analysis (X-ray diffraction). According to the results, simply increasing the dose of CaCl2 in unmodified SCDA was found to be ineffective to attain an increased rate of expansive pressure generation and the peak expansive pressure development. The increased dose of CaCl2 resulted in an accelerated expansive pressure generation, but also a lower peak expansive pressure. The approach of combining the accelerator and VEA was found to be an effective means to increase the washout resistance and the rate of expansive pressure development of modified SCDA while retaining a reasonable flowability of SCDA. Finally, the study proposes an optimum combination of VEA (welan gum, 0.1%) and the accelerator (CaCl2, 2%) by weight of SCDA to produce an SCDA with enhanced expansive pressure generation in submerged conditions, which can be effectively and safely applied for demolition and rock fragmentation.
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- 2018
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29. The Influence of Admixtures on the Hydration Process of Soundless Cracking Demolition Agents (SCDA) for Fragmentation of Saturated Deep Geological Reservoir Rock Formations
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Pathegama Gamage Ranjith, V.R.S. De Silva, Tharaka Dilanka Rathnaweera, Mandadige Samintha Anne Perera, and Bisheng Wu
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Cement ,Petroleum engineering ,0211 other engineering and technologies ,Geology ,02 engineering and technology ,Welan gum ,010502 geochemistry & geophysics ,Geotechnical Engineering and Engineering Geology ,01 natural sciences ,Petroleum reservoir ,chemistry.chemical_compound ,Cracking ,chemistry ,Demolition ,Expansive ,Pressure generation ,021101 geological & geomatics engineering ,0105 earth and related environmental sciences ,Civil and Structural Engineering - Abstract
Alternative fragmentation technologies such as soundless cracking demolition agents (SCDAs) can minimize adverse environmental impacts associated with conventional rock fracturing methods used in mining and energy industries. However, application of SCDA in deep underground environments is limited due to (1) inability of SCDA to react in saturated rock masses as a result of dilution and mass washout effects, and (2) slow expansive pressure generation in SCDA, which delays post-fracturing operations. This study addresses the first issue by modifying a generic SCDA using a viscosity-enhancing admixture (VEA), namely welan gum, to produce a hydrophobic SCDA for direct application in submerged conditions. The effect of the VEA, on the mechanical, microstructural and mineralogical morphology of hydrating SCDA was also investigated. According to the findings, adding just 0.1% of VEA by weight to the SCDA in combination with a water-reducing admixture significantly improves the washout resistance without compromising the fluidity of SCDA, however, at the expense of rapid expansive pressure generation rates. The reduction in expansive pressure, which is unfavourable for mining and energy engineering applications is caused by the interaction of VEA with the hydrating SCDA. This is evident in the SEM and XRD results observed. This urges the consideration of both positive and negative effects of welan gum in SCDA: enhancement of washout resistance and reduction of expansive pressure development prior to any field application.
- Published
- 2018
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30. An experimental evaluation of helical piles as a liquefaction-induced building settlement mitigation measure
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Ramin Motamed, Milad Jahed Orang, Ahmed Elgamal, Athul Prabhakaran, and Reza Boushehri
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Test series ,Settlement (structural) ,Foundation (engineering) ,Soil Science ,Liquefaction ,Earthquake shaking table ,Geotechnical engineering ,Geotechnical Engineering and Engineering Geology ,Pile ,Geology ,Pressure generation ,Civil and Structural Engineering - Abstract
This study evaluates the application of helical piles to reduce liquefaction-induced foundation settlement and investigates their seismic performance in liquefiable grounds. Two large-scale shake table test series, one without mitigation and one using helical piles, were conducted using the shake table facility at the University of California, San Diego. Each model was extensively instrumented and subjected to two consistently applied shaking sequences. The experimental results indicated reduced excess pore-water pressure generation around the helical pile group, attributed mainly to the densification around the piles during installation. The foundation supported on helical piles underwent almost no foundation differential settlement and tilt. The post-shaking liquefaction-induced settlement mechanisms did not affect the helical pile foundation settlement. Although this study introduced helical piles as a reliable and highly efficient measure to mitigate liquefaction-induced foundation tilt and settlement, the proper design and application of helical piles still need thorough investigation due to possible amplified superstructure response.
- Published
- 2021
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31. A new multi-anvil press employing six independently acting 8 MN hydraulic rams.
- Author
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Manthilake, M.A.G.M., Walte, N., and Frost, D.J.
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- *
DIAMOND anvil cell , *HYDRAULIC rams , *HIGH pressure (Technology) , *TUNGSTEN carbide , *TEMPERATURE measurements , *PHYSICS experiments , *DEFORMATIONS (Mechanics) - Abstract
A new large volume multi-anvil system which employs six independently acting hydraulic rams with independent oil pressurization systems has been developed for high pressure and temperature experiments. The six 8 MN hydraulic rams approach at right angles inside a composite steel plate frame and can each advance a square faceted anvil of either hardened steel or tungsten carbide. The position of each anvil can be measured relative to the frame of the press to a precision of 0.1 μ m. The press is designed to perform both deformation experiments using cubic ceramic pressure media and experiments employing eight inner cubic anvils to compress an octahedral pressure medium. During compression, the position of each anvil relative to the press frame can be precisely measured and controlled independently, thus ensuring a high level of symmetry in the compressive stress environment. The highly cubic compressive regime provides an optimal environment for the use of inner sintered diamond cubic anvils, which can potentially obtain pressures above 50 GPa. The large loading capacity (24 MN) allows larger cubic pressure media to be used at higher pressures than conventional systems. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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32. Recent advances of high-pressure generation in a multianvil apparatus using sintered diamond anvils.
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Zhai, Shuangmeng and Ito, Eiji
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EARTH sciences ,TEMPERATURE measurements ,HIGH pressure (Science) ,MATERIALS at high pressures ,SYNCHROTRON radiation ,EQUIPMENT & supplies - Abstract
Abstract: The tried and tested multianvil apparatus has been widely used for high-pressure and high-temperature experimental studies in Earth science. As a result, many important results have been obtained for a better understanding of the components, structure and evolution of the Earth. Due to the strength limitation of materials, the attainable multianvil pressure is generally limited to about 30 GPa (corresponding to about 900 km of the depth in the Earth) when tungsten carbide cubes are adopted as second-stage anvils. Compared with tungsten carbide, the sintered diamond is a much harder material. The sintered diamond cubes were introduced as second-stage anvils in a 6–8 type multianvil apparatus in the 1980s, which largely enhanced the capacity of pressure generation in a large volume press. With the development of material synthesis and processing techniques, a large sintered diamond cube (14 mm) is now available. Recently, maximum attainable pressures reaching higher than 90 GPa (corresponding to about 2700 km of the depth in the Earth) have been generated at room temperature by adopting 14-mm sintered diamond anvils. Using this technique, a few researches have been carried out by the quenched method or combined with synchrotron radiation in situ observation. In this paper we review the properties of sintered diamond and the evolution of pressure generation using sintered diamond anvils. As-yet unsolved problems and perspectives for uses in Earth Science are also discussed. [ABSTRACT FROM AUTHOR]
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- 2011
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33. Narrow-Flow-Channel-Driven EHD Gas Pump for an Advanced Thermal Management of Microelectronics.
- Author
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Jen-Shih Chang, Tsubone, Hiroaki, Harvel, Glenn D., and Urashima, Kuniko
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- *
GASOLINE pumps , *MICROELECTRONICS , *ELECTRIC discharges , *CORONA discharge , *ELECTROSTATICS , *ELECTROHYDRODYNAMICS , *ELECTRODYNAMICS , *PUMPING machinery - Abstract
In order to study the feasibility of applying electrohydrodynamic (EHD) gas pumps for advanced thermal management of microelectronics, an experimental investigation was conducted to drive gas flow through a narrow flow channel by an EHD gas pump. The net gas flow induced by corona discharge was generated by a push-fan (PF)-type EHD gas pump with and without a partially covered corona wire and nonparallel ground plate electrodes to transfer gas through millimeter-order circular channels. Therefore, it is important to know the effect of a narrow channel on the characteristics of the EHD gas pump with the corona wire electrode covered. The results show that the effects of narrow circular flow channels significantly influence the flow characteristics of the PF-type EHD gas pump and that the use of an insulator on the corona wire electrode can significantly enhance the current flux density and the pump performance under dc positive applied voltage. [ABSTRACT FROM AUTHOR]
- Published
- 2010
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34. Shaking-Induced Sublayer Vertical Strains of Saturated Sands Estimated from Partially Drained Dynamic Centrifuge Tests
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Joon Han Kim and Scott M. Olson
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Centrifuge ,Settlement (structural) ,Effective stress ,Soil water ,Compressibility ,Earthquake shaking table ,Magnitude (mathematics) ,Geotechnical engineering ,Geotechnical Engineering and Engineering Geology ,Geology ,Pressure generation - Abstract
Earthquake-induced free-field settlement of coarse-grained soils has historically been assessed using laboratory element tests under drained or undrained conditions. However, in saturated sands, dynamic centrifuge and 1g shaking table tests illustrate that excess porewater pressure generation/dissipation and settlement occur simultaneously during shaking under partially drained conditions. The average vertical strains computed from measured surface settlements in these tests neglect (1) the impact of effective stress on compressibility and (2) settlements that occur in denser and potentially nonliquefiable sands present in the centrifuge models. Here, the authors employ a simple procedure that uses measured porewater pressure and surface settlement time histories from partially drained centrifuge and 1g shaking table tests to properly distribute vertical strain throughout the coarse-grained soil profiles, thereby incorporating variations of effective stress and relative density on vertical strain. The vertical strains are resolved into a shaking-induced component and a post-shaking reconsolidation component, and the procedure yields computed surface settlement time histories that reasonably match the rate and magnitude of measured settlements both during and after shaking. Using this procedure, we interpreted 151 individual (sublayer) estimates of vertical strain from 34 shaking events applied in dynamic centrifuge and 1g shaking table tests. Combined with the sublayer shaking intensities, the 151 vertical strain values constitute a new database that can be used to develop shaking-induced settlement correlations for realistic partially drained conditions.
- Published
- 2021
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35. A new 6-axis apparatus to squeeze the Kawai-cell of sintered diamond cubes
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Ito, Eiji, Katsura, Tomoo, Yamazaki, Daisuke, Yoneda, Akira, Tado, Masashi, Ochi, Takahiro, Nishibara, Eiichi, and Nakamura, Akihiro
- Subjects
- *
CELLULAR mechanics , *DIAMONDS , *SINTERING , *X-rays , *PRESSURE , *IRON oxides - Abstract
Abstract: In order to overcome disadvantages of the DIA type press in squeezing the Kawai-cell, such as uneven compression between the upper and lower anvils and the four surrounding anvils and frictional loss of applied load in the guide block, we have developed a new 6-axis apparatus in which the movements of the six anvils are controlled by a servo mechanism. It is possible to keep the Kawai-cell cubic within an accuracy of ±2μm during compression and decompression. Pressure generation using sintered diamond cubic anvils with edge length of 14.0mm and a truncation of 1.5mm has been carried out up to ca. 60GPa by measuring electrical resistance of GaP, Zr, and Fe2O3. The results are compared with our previous calibration, carried out using an almost the same sample setup for identical anvils at SPring-8, by means of in situ X-ray observation. It is demonstrated that a significant amount of the applied load is lost by friction when the Kawai-cell is squeezed in the DIA type press. The load loss increases with increasing load, or pressure, and amounts to 45% at ca. 60GPa. Therefore the 6-axis apparatus is very advantageous to generate higher pressures in the Kawai-cell. However, individual control of the anvils sometimes induces a runaway advancement of the anvils which brings about an abrupt increase of pressure. [Copyright &y& Elsevier]
- Published
- 2009
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36. Effects of pre-heated pyrophyllite gaskets on high-pressure generation in the Kawai-type multi-anvil experiments.
- Author
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Zhai, Shuangmeng, Ito, Eiji, and Yoneda, Akira
- Subjects
- *
PYROPHYLLITE , *HIGH pressure (Science) , *X-ray diffraction , *RAMAN spectroscopy , *TEMPERATURE - Abstract
Pyrophyllite gaskets heated up to 900 °C for 1 h and raw gaskets (without heating treatment) were characterized by X-ray diffraction and Raman spectroscopy. These gaskets were used in multi-anvil high-pressure experiments to investigate the effect of pre-heating on pressure generation in Kawai-type apparatus. The results show that the gaskets heated at low temperatures (200-500 °C) have no change in structure and those heated at higher temperatures (600-900 °C) dehydroxylate gradually. No structural OH is observed in 900 °C pre-heated gasket from Raman spectroscopy indicating a complete dehydroxylation. The low temperature (200-500 °C) pre-heated gasket causes a limited effect on pressure generation, and the high-temperature (600-900 °C) pre-heated gasket has a relatively large negative effect on pressure generation. [ABSTRACT FROM AUTHOR]
- Published
- 2008
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37. Flow characteristics of dc wire-non-parallel plate electrohydrodynamic gas pumps
- Author
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Tsubone, H., Ueno, J., Komeili, B., Minami, S., Harvel, G.D., Urashima, K., Ching, C.Y., and Chang, J.S.
- Subjects
- *
ATMOSPHERIC pressure , *FLUID dynamics , *LAMINAR flow , *PRESSURE - Abstract
Abstract: An experimental investigation has been conducted to study the effect of grounded electrode location and polarity on time averaged discharge current, velocity profile, volumetric flow rate and pressure generation for a wire-non-parallel plate type EHD gas pump. The experiments were conducted with two different electrode configurations for the negative and positive applied voltages from 0 to 14kV at atmospheric pressure and room temperature, where air was used as the working fluid. The experimental results showed that: (1) a maximum gas velocity of 1.9m/s corresponding to a volumetric flow rate of 44l/min was observed; (2) the volumetric flow rate, gas velocity and pressure generation increased with increasing applied dc voltage or EHD number; (3) a non-linear relationship between the pressure generation and the gas velocity was observed and the flow generated was always turbulent or limited re-circulating laminar flow. The mechanism of unidirectional EHD generation will be discussed in detail. [Copyright &y& Elsevier]
- Published
- 2008
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38. The Nature of Feeding in Infants With Unrepaired Cleft Lip and/or Palate Compared With Healthy Noncleft Infants.
- Author
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Masarei, A. G., Sell, D., Habel, A., Mars, Michael, Sommerlad, B. C., and Wade, A.
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INFANT nutrition ,CLEFT palate children ,CLEFT lip ,INFANT care ,LIP abnormalities - Abstract
Objective: Feeding difficulties are reported widely in infants with cleft lip and! or palate. There is, however, a paucity of objective information about the feeding patterns of these infants. This study compared patterns of feeding in infants with unrepaired cleft lip and palate with healthy noncleft infants of a similar age. Setting: North Thames Regional Cleft Centre. The noncleft cohort was recruited from West Middlesex University Hospital, a general hospital with similar demographics. Participants: Fifty newborn infants with nonsyndromic complete unilateral cleft lip and palate or a cleft of the soft and at least two thirds of the hard palate who were referred to the North Thames Regional Cleft Centre participated. Parents of 20 randomly selected, noncleft infants agreed to participate. Main Outcome Measures: Feeding patterns were rated using the Neonatal Oral Motor Assessment Scale. Additional objective information was collected using the Great Ormond Street Measurement of Infant Feeding (Masarei et al., 2001; Masarei, 2003). Results: Infants with nonsyndromic complete unilateral cleft lip and palate or a cleft of the soft and at least two thirds of the hard palate had less efficient sucking patterns than their noncleft peers had. They used shorter sucks (mean difference, 0.30 second; p < .0005), a faster rate of sucking (mean difference, 34.20 sucks/second; p < .0005), higher suck-swallow ratios (mean difference, 1.87 sucks/swallow; p < .0005), and a greater proportion of intraoral positive pressure generation (mean difference, 45.97% positive pressure; p < .0005). Conclusions: This study demonstrated that the sucking patterns of infants with nonsyndromic complete unilateral cleft lip and palate or a cleft of the soft and at least two thirds of the hard palate differ from those of their noncleft peers. [ABSTRACT FROM AUTHOR]
- Published
- 2007
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39. A model of transport of fuel gases in a charring solid and its application to opposed-flow flame spread.
- Author
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Baum, Howard R. and Atreya, Arvind
- Subjects
THERMAL properties of gases ,FIRE testing ,FLAMMABILITY ,THERMOCHEMISTRY - Abstract
Abstract: This paper outlines the development of a mathematical model for the transport of gases through the char matrix of a burning solid. Two basic assumptions are made. First, the gases evolved by the degradation of the virgin material are transported by pressure differences through a network of narrow passageways created in the char by the conversion of material from the solid to the gas phase. This process is treated as flow through a porous medium, with the mass flux related to the pressure gradient by Darcy’s law. Second, the gas temperature is the same as the local char temperature. This model is first used to study the time-dependent thermal degradation of a semi-infinite charring solid heated above the charring temperature. Then, the opposed flow flame spread treated by Atreya and Baum [Atreya, A., Baum, H.R., Proc. Combust. Inst., 29 (2002) 227–236] is revisited. It was found that the solution to the condensed phase flame spread problem is identical to the initial transient problem. Weak dependence of the solution on the accumulation parameter ‘β’ validates the assumption made in [Atreya, A., Baum, H.R., Proc. Combust. Inst., 29 (2002) 227–236] and completes the flame spread solution. Fuel mass flux follows the heat flux lines and is normal to the isobars. Calculations using representative values for wood show that the pressure generation at the char–virgin material interface is considerable and equal to 13.27kPa. Finally, in view of the fact that the nonlinear pressure equation poses considerable numerical difficulties, this analytical solution may help in determining the stability and accuracy of the numerical scheme used for more complicated problems. [Copyright &y& Elsevier]
- Published
- 2007
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40. Tongue Pressure Production and Submental Surface Electromyogram Activities During Tongue-Hold Swallow with Different Holding Positions and Tongue Length
- Author
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Masako Fujiu-Kurachi, Shigehiro Fujiwara, Kazuhiro Hori, Takahiro Ono, and Yoshinobu Maeda
- Subjects
Adult ,Male ,Electromyography ,Tongue pressure ,Young Adult ,030507 speech-language pathology & audiology ,03 medical and health sciences ,Speech and Hearing ,0302 clinical medicine ,Tongue ,Pressure ,medicine ,Humans ,Muscle activity ,Orthodontics ,medicine.diagnostic_test ,business.industry ,Gastroenterology ,030206 dentistry ,Deglutition ,medicine.anatomical_structure ,Otorhinolaryngology ,Female ,Tongue protrusion ,Deglutition Disorders ,0305 other medical science ,business ,Pressure generation - Abstract
Our previous study regarding the tongue-hold swallow (THS) demonstrated that the tongue-to-palate contact during THS could be influenced by the maximum tongue protrusion length (MTPL) of individual subjects, resulting in two different patterns of pressure generation. The present study further analyzed the influence of MTPL on the tongue pressure production along with submental surface electromyography (sEMG) during THS, in order to establish an index to better control THS effects. Tongue pressure using a sensor sheet system and concurrent submental sEMG activities were measured during swallowing tasks in 18 healthy young adults. Task conditions comprised THS at two different degrees of tongue protrusion and dry swallow. Tongue pressures and sEMG activities were compared among three task conditions, and correlations of MTPL with tongue pressure were also investigated. Additionally, a ROC curve was used to find a cut-off value for MTPL to predict changes (increases and decreases) in tongue pressure during THS. The duration and the amount of submental muscle activity increased concurrently during THS. Two trends were shown on the change in tongue pressure at the posterior-circumferential part of the hard palate during THS compared to dry swallow; the maximal magnitude and the integrated value of tongue pressure increased in some subjects, while these values decreased in others. Thirty-two millimeters was found to be the cut-off value of MTPL, which distinguishes increase/decrease pattern of tongue pressure with sensitivities of 60.0-85.7%. The present finding suggests that more reliable THS effects should be attainable using MTPL to set the tongue-hold position.
- Published
- 2017
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41. Pressure generation to 65 GPa in a Kawai-type multi-anvil apparatus with tungsten carbide anvils
- Author
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Daisuke Yamazaki, Yoshinori Tange, Takafumi Yamamoto, Dmitry Druzhbin, Zhaodong Liu, Takayuki Ishii, Tomoo Katsura, Yuji Higo, Fang Xu, Noriyoshi Tsujino, Takaaki Kawazoe, Takashi Yoshino, and Lin Wang
- Subjects
Diffraction ,Materials science ,010504 meteorology & atmospheric sciences ,Modulus ,Diamond ,Mineralogy ,engineering.material ,010502 geochemistry & geophysics ,Condensed Matter Physics ,01 natural sciences ,Synchrotron ,Diamond anvil cell ,law.invention ,chemistry.chemical_compound ,chemistry ,law ,Tungsten carbide ,engineering ,Composite material ,Pressure generation ,0105 earth and related environmental sciences - Abstract
We have expanded the pressure ranges at room and high temperatures generated in a Kawai-type multi-anvil apparatus (KMA) using tungsten carbide (WC) anvils with a high hardness of Hv = 2700 and a Young’s modulus of 660 GPa. At room temperature, a pressure of 64 GPa, which is the highest pressure generated with KMA using WC anvils in the world, was achieved using 1°-tapered anvils with a 1.5-mm truncation. Pressures of 48–50 GPa were generated at high temperatures of 1600–2000 K, which are also higher than previously achieved. Tapered anvils make wide anvil gaps enabling efficient X-ray diffraction. The present pressure generation technique can be used for studying the upper part of the Earth’s lower mantle down to 1200 km depth without sintered diamond anvils.
- Published
- 2017
- Full Text
- View/download PDF
42. Load-carrying capacity generation in squeeze film action
- Author
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Stolarski, T.A. and Chai, Wei
- Subjects
- *
NUMERICAL analysis , *SQUEEZED light , *QUANTUM optics , *QUANTUM theory - Abstract
Abstract: The mechanism of squeeze action is explored using results of numerical analyses and physical explanations. The relationship between the mean film force and the load the squeeze film could support is established. It is concluded that the high viscous resistance around the contact boundary is the source of squeeze air film build-up. Repeated compression and expansion of air contribute to the formation of unsymmetric pressure field and load-carrying capacity. [Copyright &y& Elsevier]
- Published
- 2006
- Full Text
- View/download PDF
43. Analysis of flow and mixing in screw elements of corotating twin‐screw extruders via SPH
- Author
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Johannes Khinast, Josip Matić, and Andreas Eitzlmayr
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Environmental Engineering ,Materials science ,General Chemical Engineering ,Flow (psychology) ,Time evolution ,02 engineering and technology ,Mechanics ,021001 nanoscience & nanotechnology ,Power (physics) ,Exponential function ,Smoothed-particle hydrodynamics ,020401 chemical engineering ,0204 chemical engineering ,0210 nano-technology ,Pressure generation ,Intensity (heat transfer) ,Mixing (physics) ,Biotechnology - Abstract
Due to its meshless nature, the smoothed particle hydrodynamics method (SPH) provides high potential for the simulation of free-surface flows and mixing in complex geometries. We used SPH to analyze the flow inside five typical screw elements of corotating twin-screw extruders, two conveying elements, two kneading elements and a mixing element. Our results show conveying capabilities, pressure generation and power input for various operation states, completely and partially filled. We conducted a detailed mixing analysis based on tracer particles, which yielded the time evolution of the intensity of segregation for different tracers. From that, we determined exponential mixing rates, which describe the relative decrease of the intensity of segregation per screw revolution and characterize the mixing performance in different operation states. This provides valuable input information for simplified models of extruders, which are relevant to industrial applications and can significantly contribute to the efficient design, optimization and scale-up of extruders. © 2017 American Institute of Chemical Engineers AIChE J, 63: 2451–2463, 2017
- Published
- 2017
- Full Text
- View/download PDF
44. Theoretical investigation of boundary slip on the hydrodynamic lubrication performance in pocketed bearings including cavitation
- Author
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Jamari Jamari, Ariawan Wahyu Pratomo, Mohammad Tauviqirrahman, Dirk J. Schipper, and Muchammad Muchammad
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Cavitation ,Materials science ,business.industry ,Mechanical Engineering ,Boundary slip ,Fluid bearing ,02 engineering and technology ,Structural engineering ,Slip (materials science) ,Mechanics ,Surfaces and Interfaces ,021001 nanoscience & nanotechnology ,n/a OA procedure ,Surfaces, Coatings and Films ,020303 mechanical engineering & transports ,0203 mechanical engineering ,Shear stress ,0210 nano-technology ,business ,Pocketed bearing ,Pressure generation ,NLA ,Hydrodynamic performance - Abstract
Boundary slip in bearings is becoming more and more popular to improve the hydrodynamic performance (pressure and shear stress). However, most of previously published works regarding textured bearings neglected the cavitation effect and make their results questionable. The main aim of this paper is to investigate the hydrodynamic performance of slip pocketed bearings considering cavitation by a theoretical approach. Cavitation was of particular interest with respect to pressure generation and shear stress. One main result presented here was that slip over the whole surface could retard the presence of cavitation and therefore the generated pressure and shear stress could be optimal. The work presented here leads to a design reference guideline that could be used by the designer/engineer to design slip pocketed bearings for improving the hydrodynamic performance.
- Published
- 2017
45. Expiratory Pressure Generation In Adult Survivors Of Preterm Birth
- Author
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Joseph W. Duke, Denise A. Ocampo, and Elizabeth A. Gideon
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medicine.medical_specialty ,business.industry ,Internal medicine ,Cardiology ,medicine ,Physical Therapy, Sports Therapy and Rehabilitation ,Orthopedics and Sports Medicine ,business ,Pressure generation - Published
- 2020
- Full Text
- View/download PDF
46. Numerical Study on Pressure Generation Mechanism of Oil Film under Oil Control Ring
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Wataru Kobayashi, Akemi Ito, Susumu Degawa, Koji Kikuhara, and Koichi Nishibe
- Subjects
Mechanism (engineering) ,Materials science ,Chemical engineering ,Oil film ,Ring (chemistry) ,Pressure generation - Published
- 2019
- Full Text
- View/download PDF
47. Experimental evaluation and analytical model of the pressure generated by elastic compression garments on a deformable human limb analogue
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Geoffrey M. Spinks, Christopher J. Richards, and Julie R. Steele
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Elastic compression ,Computer science ,Biomedical Engineering ,Biophysics ,Mechanical engineering ,Extremities ,Equipment Design ,Models, Theoretical ,Compression (physics) ,Clothing ,Compressibility ,Pressure ,Humans ,Material properties ,Pressure generation - Abstract
Compression garments are extensively used for various therapeutic treatments and are expected to deliver accurate and reproducible compression pressures. This study focuses on developing an analytical model to predict the pressure generation by compression garments on human limb analogues. The analogues consisted of non-compressible and compressible cylinders that were chosen as the first step towards evaluating pressure generation on real human limbs. An experimental platform was developed to quantify the relationship between material properties, initial garment extension and pressure. A mathematical model was presented that provided greater accuracy in predicting the pressure generated by compression garments than the existing Young-Laplace equation for compressible limb analogues.
- Published
- 2019
48. Complete Restoration of Respiratory Muscle Function in Subjects With Spinal Cord Injury: Interventional Clinical Trial
- Author
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Robert T. Geertman, Krzysztof E. Kowalski, Anthony F. DiMarco, and Kutaiba Tabbaa
- Subjects
030506 rehabilitation ,medicine.medical_treatment ,Physical Therapy, Sports Therapy and Rehabilitation ,03 medical and health sciences ,0302 clinical medicine ,Respiration ,medicine ,Respiratory muscle ,Humans ,Spinal cord injury ,Spinal Cord Injuries ,Mechanical ventilation ,business.industry ,Rehabilitation ,respiratory system ,medicine.disease ,Respiratory Muscles ,respiratory tract diseases ,Clinical trial ,Diaphragm pacing ,Anesthesia ,0305 other medical science ,Airway ,business ,030217 neurology & neurosurgery ,Pressure generation - Abstract
OBJECTIVES The aim of this study was to assess the safety and efficacy of complete restoration of respiratory muscle function in subjects with spinal cord injury. METHODS This was an interventional study investigating three subjects maintained on a diaphragm pacing system who were implanted with the spinal cord stimulation system to restore cough. Peak expiratory airflow and airway pressure generation were the primary physiologic outcome measures; an assessment of the degree of difficulty in raising secretions was the primary clinical outcome measure. RESULTS Mean peak expiratory airflow and airway pressure generation during spontaneous efforts were 1.7 ± 0.2 L/s and 31 ± 7 cmH2O, respectively. When spinal cord stimulation was applied after pacing volume associated with the subject's maximum inspiratory effort and synchronized with the subject's maximum expiratory effort, peak expiratory airflow and airway pressure generation were 9.0 ± 1.9 L/s and 90 ± 6 cmH2O, respectively (P < 0.05). Moreover, each subject experienced much greater ease in raising secretions and marked improvement in the ease in raising secretions compared with other methods. CONCLUSIONS Complete restoration of respiratory muscle function can be safely and effectively achieved in the same individuals with spinal cord injury. Spinal cord stimulation results in peak expiratory airflow and airway pressure generation characteristic of a normal cough, whereas diaphragm pacing was successful in maintaining patients off mechanical ventilation.
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- 2019
49. The effect of briquette composition on coking pressure generation
- Author
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E. Díaz-Faes, L. Florentino-Madiedo, Carmen Barriocanal, Research Fund for Coal and Steel, Barriocanal Rueda, Carmen, and Barriocanal Rueda, Carmen [0000-0001-5156-0970]
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Briquette ,Materials science ,020209 energy ,General Chemical Engineering ,Energy Engineering and Power Technology ,Biomass ,02 engineering and technology ,Coking pressure ,complex mixtures ,020401 chemical engineering ,Briquettes ,0202 electrical engineering, electronic engineering, information engineering ,medicine ,Coal ,0204 chemical engineering ,Coal tar ,business.industry ,Organic Chemistry ,Metallurgy ,technology, industry, and agriculture ,Coke ,Coke quality ,Bulk density ,respiratory tract diseases ,Fuel Technology ,Composition (visual arts) ,business ,Pressure generation ,medicine.drug - Abstract
A coal normally used in coking blends was employed to study the effect of briquettes on coking pressure. The study is focused primarily on two parameters i) bulk density which increases with the use of briquettes and ii) the composition of the briquettes containing materials which have contrary effects on coking pressure. Four briquettes with different compositions were prepared, two of them containing biomass. A non-coking coal and coal tar as binder were included in the composition of all four briquettes. The permeability of the plastic phase to gas flow was studied for blends of coking coal with individual briquette components and for blends of coking coal with 15 wt% of the four briquettes. The coking pressure was measured in a movable wall oven and the mechanical strength, coke reactivity and post-reaction strength of the cokes were assessed by means of standard tests, JIS, CRI/CSR. It was found that all four briquettes produced lower coking pressure than that generated by the coking coal regardless of the increase in bulk density while the cokes retained their quality up to 15 wt% briquette addition., The research leading to these results has received funding from the European Union's Research Fund for Coal and Steel (RFCS) research program under grant agreements No. [RFCR-CT-2014-00006] and No [RFCS-CT-2010-00006].
- Published
- 2019
50. A novel mouse tail lymphedema model for observing lymphatic pump failure during lymphedema development
- Author
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J. Brandon Dixon, Matthew T. Cribb, M. Weiler, Zhanna Nepiyushchikh, and Tyler S. Nelson
- Subjects
0301 basic medicine ,Male ,Pathology ,medicine.medical_specialty ,Future studies ,Secondary lymphedema ,lcsh:Medicine ,Article ,03 medical and health sciences ,Mice ,0302 clinical medicine ,medicine ,Animals ,Lymphedema ,Obesity ,lcsh:Science ,Lymphatic Vessels ,Multidisciplinary ,Lymphatic pump ,business.industry ,Disease progression ,lcsh:R ,Endothelial Cells ,medicine.disease ,Mice, Inbred C57BL ,Circulation ,Disease Models, Animal ,030104 developmental biology ,Lymphatic system ,Cardiovascular diseases ,Disease Progression ,lcsh:Q ,medicine.symptom ,Lymphatic function ,business ,Biomedical engineering ,030217 neurology & neurosurgery ,Pressure generation - Abstract
It has been suggested that many forms of secondary lymphedema in humans are driven by a progressive loss of lymphatic pump function after an initial risk-inducing event. However, the link between pump failure and disease progression has remained elusive due to experimental challenges in the clinical setting and a lack of adequate animal models. Using a novel surgical model of lymphatic injury, we track the adaptation and functional decline of the lymphatic network in response to surgery. This model mimics the histological hallmarks of the typical mouse tail lymphedema model while leaving an intact collecting vessel for analysis of functional changes during disease progression. Lymphatic function in the intact collecting vessel negatively correlated with swelling, while a loss of pumping pressure generation remained even after resolution of swelling. By using this model to study the role of obesity in lymphedema development, we show that obesity exacerbates acquired lymphatic pump failure following lymphatic injury, suggesting one mechanism through which obesity may worsen lymphedema. This lymphatic injury model will allow for future studies investigating the molecular mechanisms leading to lymphedema development.
- Published
- 2019
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