Chirped Probe Pulse Femtosecond Cars H2Measurements At Elevated Pressure And Temperature

Reliable measurement of the CO 2 diffusion coefficient in consolidated oil-saturated porous media is critical for the design and performance of CO 2 -enhanced oil recovery (EOR) and carbon capture and storage (CCS) projects. A thorough experimental investigation of the supercritical CO 2 diffusion in n -decane-saturated Berea cores with permeabilities of 50 and 100 mD was conducted in this study at elevated pressure (10–25 MPa) and temperature (333.15–373.15 K), which simulated actual reservoir conditions. The supercritical CO 2 diffusion coefficients in the Berea cores were calculated by a model appropriate for diffusion in porous media based on Fick's Law. The results show that the supercritical CO 2 diffusion coefficient increases as the pressure, temperature and permeability increase. The supercritical CO 2 diffusion coefficient first increases slowly at 10 MPa and then grows significantly with increasing pressure. The impact of the pressure decreases at elevated temperature. The effect of permeability remains steady despite the temperature change during the experiments. The effect of gas state and porous media on the supercritical CO 2 diffusion coefficient was further discussed by comparing the results of this study with previous study. Based on the experimental results, an empirical correlation for supercritical CO 2 diffusion coefficient in n -decane-saturated porous media was developed. The experimental results contribute to the study of supercritical CO 2 diffusion in compact porous media.

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Investigation of mixing processes of effusion cooling air and main flow in a single sector model gas turbine combustor at elevated pressure

International Journal of Heat and Fluid Flow ◽

10.1016/j.ijheatfluidflow.2020.108768 ◽

2021 ◽

Vol 88 ◽

pp. 108768

Author(s):

Max Greifenstein ◽

Andreas Dreizler

Keyword(s):

Gas Turbine ◽

Elevated Pressure ◽

Main Flow ◽

Gas Turbine Combustor ◽

Mixing Processes ◽

Sector Model ◽

Model Gas Turbine Combustor ◽

Cooling Air

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Rectal–vaginal pressure gradient in patients with pelvic organ prolapse and symptomatic rectocele

BMC Women s Health ◽

10.1186/s12905-021-01304-6 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Cheng Tan ◽

Man Tan ◽

Jing Geng ◽

Jun Tang ◽

Xin Yang

Keyword(s):

Pelvic Organ Prolapse ◽

Pressure Gradient ◽

Obstructed Defecation ◽

Elevated Pressure ◽

Pelvic Organ ◽

Lower Grade ◽

Translabial Ultrasound ◽

Rectal Ampulla ◽

The Relationship ◽

Posterior Vaginal Prolapse

Abstract Objective The aim of this study is to examine the relationship between rectal–vaginal pressure and symptomatic rectocele in patients with pelvic organ prolapse (POP). Method Patients with posterior vaginal prolapse staged III or IV in accordance with the POP Quantitation classification method who were scheduled for pelvic floor reconstructive surgery in the years 2016–2019 were included in the study. Rectocele was diagnosed using translabial ultrasound, and obstructed defecation (OD) was diagnosed in accordance with the Roma IV diagnostic criteria. Both rectal and vaginal pressure were measured using peritron manometers at maximum Vasalva. To ensure stability, the test was performed three times with each patient. Results A total of 217 patients were enrolled in this study. True rectocele was diagnosed in 68 patients at a main rectal ampulla depth of 19 mm. Furthermore, 36 patients were diagnosed with OD. Symptomatic rectocele was significantly associated with older age (p < 0.01), a higher OD symptom score (p < 0.001), and a lower grade of apical prolapse (p < 0.001). The rectal–vaginal pressure gradient was higher in patients with symptomatic rectocele (37.4 ± 11.7 cm H2O) compared with patients with asymptomatic rectocele (16.9 ± 8.4 cm H2O, p < 0.001), and patients without rectocele (17.1 ± 9.2 cm H2O, p < 0.001). Conclusion The rectal–vaginal pressure gradient was found to be a risk factor for symptomatic rectocele in patients with POP. A rectal–vaginal pressure gradient of > 27.5 cm H2O was suggested as the cut-off point of the elevated pressure gradient.

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The Impact of Pressure and Hydrocarbons on NOx Abatement over Cu- and Fe-Zeolites at Pre-Turbocharger Position

Catalysts ◽

10.3390/catal11030336 ◽

2021 ◽

Vol 11 (3) ◽

pp. 336

Author(s):

Deniz Zengel ◽

Simon Barth ◽

Maria Casapu ◽

Jan-Dierk Grunwaldt

Keyword(s):

Catalytic Reduction ◽

Elevated Pressure ◽

Systematic Investigation ◽

Diesel Oxidation Catalyst ◽

Zeolite Catalysts ◽

Oxidation Catalyst ◽

Pollutant Concentrations ◽

Oxidation Of Hydrocarbons ◽

Negative Effect ◽

The Impact

Positioning the catalysts in front of the turbocharger has gained interest over recent years due to the earlier onset temperature and positive effect of elevated pressure. However, several challenges must be overcome, like presence of higher pollutant concentrations due to the absence or insufficient diesel oxidation catalyst volume at this location. In this context, our study reports a systematic investigation on the effect of pressure and various hydrocarbons during selective catalytic reduction (SCR) of NOx with NH3 over the zeolite-based catalysts Fe-ZSM-5 and Cu-SSZ-13. Using a high-pressure catalyst test bench, the catalytic activity of both zeolite catalysts was measured in the presence and absence of a variety of hydrocarbons under pressures and temperatures resembling the conditions upstream of the turbocharger. The results obtained showed that the hydrocarbons are incompletely converted over both catalysts, resulting in numerous byproducts. The emission of hydrogen cyanide seems to be particularly problematic. Although the increase in pressure was able to improve the oxidation of hydrocarbons and significantly reduce the formation of HCN, sufficiently low emissions could only be achieved at high temperatures. Regarding the NOx conversion, a boost in activity was obtained by increasing the pressure compared to atmospheric reaction conditions, which compensated the negative effect of hydrocarbons on the SCR activity.

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The effect of high pressure treatment on the quality of chicken breast meat

Hrvatski časopis za prehrambenu tehnologiju biotehnologiju i nutricionizam ◽

10.31895/hcptbn.14.3-4.6 ◽

2020 ◽

Vol 14 (3-4) ◽

pp. 76-81

Author(s):

Nives Marušić Radovčić ◽

Damir Ježek ◽

Ksenija Markov ◽

Jadranka Frece ◽

Duška Ćurić ◽

...

Keyword(s):

High Pressure ◽

Treatment Time ◽

Elevated Pressure ◽

Quality Parameters ◽

High Pressure Processing ◽

Chicken Breast ◽

Moisture Uptake ◽

Breast Meat ◽

Chicken Breast Meat ◽

Cooking Yield

In the present work, the effect of high pressure processing (HPP) (0, 100, 200 and 300 MPa) and different treatment time (5 and 10 minutes) on the moisture uptake, cooking yield, colour and texture, as well as microbial population of chicken breast fillets was investigated. The application of high hydrostatic pressure resulted in a modification of quality parameters of chicken breast meat. By increasing pressure and time of the treatment the moisture uptake was reduced: samples treated with 300 MPa for 10 min had the lowest moisture uptake values. Cooking yield was not affected by HPP treatments. Increased pressure affected the colour by increasing L*, a* and b* values (only HPP treatment of 100 MPa in duration of 5 and 10 minutes did not affect colour of chicken breast meat). Lower pressures (100 and 200 MPa) tenderized, whereas elevated pressure (300 MPa) increased hardness in chicken breast fillets. Higher level of pressure (300 MPa) reduced bacteria count by about 3.0 – 5.3 log (CFU/g), depending on the microorganism and duration of the process.

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Factors Contributing to Increased Blast Overpressure Inside Modern Ballistic Helmets

Applied Sciences ◽

10.3390/app10207193 ◽

2020 ◽

Vol 10 (20) ◽

pp. 7193

Author(s):

Maciej Skotak ◽

Jonathan Salib ◽

Anthony Misistia ◽

Arturo Cardenas ◽

Eren Alay ◽

...

Keyword(s):

Experimental Study ◽

Shock Tube ◽

Principle Component Analysis ◽

Hot Spots ◽

Shape Factor ◽

Elevated Pressure ◽

Focal Points ◽

Parietal Region ◽

Blast Overpressure ◽

Pressure Fields

This study demonstrates the orientation and the "shape factor" have pronounced effects on the development of the localized pressure fields inside of the helmet. We used anatomically accurate headform to evaluate four modern combat helmets under blast loading conditions in the shock tube. The Advanced Combat Helmet (ACH) is used to capture the effect of the orientation on pressure under the helmet. The three modern combat helmets: Enhanced Combat Helmet (ECH), Ops-Core, and Airframe, were tested in frontal orientation to determine the effect of helmet geometry. Using the unhelmeted headform data as a reference, we characterized pressure distribution inside each helmet and identified pressure focal points. The nature of these localized “hot spots” is different than the elevated pressure in the parietal region of the headform under the helmet widely recognized as the under-wash effect also observed in our tests. It is the first experimental study which indicates that the helmet presence increased the pressure experienced by the eyes and the forehead (glabella). Pressure fingerprinting using an array of sensors combined with the application of principle component analysis (PCA) helped elucidate the subtle differences between helmets.

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