scholarly journals Effect of flow rate, duty cycle, amplitude, and treatment Time of ultrasonic regimens towardsEscherichia coliharbouring lipase

2017 ◽  
Vol 206 ◽  
pp. 012021
Author(s):  
W S A W Omar ◽  
A Z Sulaiman ◽  
A Ajit ◽  
Y Chisti ◽  
A L T Chor
Keyword(s):  
Flow Rate ◽  
Duty Cycle ◽  
Treatment Time ◽  
Cycle Amplitude

scholarly journals Heterogeneous Bonding of PMMA and Double-Sided Polished Silicon Wafers through H2O Plasma Treatment for Microfluidic Devices

Coatings ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 580
Author(s):  
Chao-Ching Chiang ◽  
Philip Nathaniel Immanuel ◽  
Yi-Hsiung Chiu ◽  
Song-Jeng Huang
Keyword(s):  
Plasma Treatment ◽  
Flow Rate ◽  
Gas Flow ◽  
Treatment Time ◽  
Optical Emission ◽  
Microfluidic Devices ◽  
Oh Radicals ◽  
Gas Flow Rate ◽  
Oh Groups ◽  
Plasma Treatment Time

In this work we report on a rapid, easy-to-operate, lossless, room temperature heterogeneous H2O plasma treatment process for the bonding of poly(methyl methacrylate) (PMMA) and double-sided polished (DSP) silicon substrates by for utilization in sandwich structured microfluidic devices. The heterogeneous bonding of the sandwich structure produced by the H2O plasma is analyzed, and the effect of heterogeneous bonding of free radicals and high charge electrons (e−) in the formed plasma which causes a passivation phenomenon during the bonding process investigated. The PMMA and silicon surface treatments were performed at a constant radio frequency (RF) power and H2O flow rate. Changing plasma treatment time and powers for both processes were investigated during the experiments. The gas flow rate was controlled to cause ionization of plasma and the dissociation of water vapor from hydrogen (H) atoms and hydroxyl (OH) bonds, as confirmed by optical emission spectroscopy (OES). The OES results show the relative intensity peaks emitted by the OH radicals, H and oxygen (O). The free energy is proportional to the plasma treatment power and gas flow rate with H bonds forming between the adsorbed H2O and OH groups. The gas density generated saturated bonds at the interface, and the discharge energy that strengthened the OH-e− bonds. This method provides an ideal heterogeneous bonding technique which can be used to manufacture new types of microfluidic devices.

Thermal plasma treatment of stormwater detention pond sludge

2008 ◽  
Vol 80 (9) ◽  
pp. 1993-2002 ◽  
Author(s):  
Jen-Shih Chang ◽  
Helena O. L. Li ◽  
Yiping Guo
Keyword(s):  
Plasma Treatment ◽  
Flow Rate ◽  
Thermal Plasma ◽  
Treatment Time ◽  
Air Flow ◽  
Sediment Quality ◽  
Air Flow Rate ◽  
Element Analysis ◽  
Weight Percentage ◽  
Detention Pond

A thermal plasma treatment experiment was conducted on stormwater detention pond sludge. The original sludge compositions were analyzed by neutron activation multi-element analysis. Thirty-two elements were detected in the sludge samples, and nine of them were below detection limit. The assessment of Zn, As, Mn, and Fe concentrations against the Ontario Ministry of Environment's Sediment Quality Guidelines indicated a marginal-to-significant pollution, and the concentration of Cr presented a gross pollution. After thermal plasma treatment, the mean weight percentage removal at 0 and 2 L/min of air flow rates was 2.78 ± 0.51 and 3.85 ± 1.35 %, respectively. The maximum weight removal of 5.87 % was achieved with 2 L/min air flow rate and 2 h of treatment time. Reduction of total organic carbon (TOC) increased with increasing treatment time and air flow rate. Eight gas compounds, CO, CO2, NO, NO2, NOx, SO2, H2S, and CxHy were measured and observed during the treatment process.

Influence of inspiratory flow rate and frequency on O2 cost of resistive breathing in humans

1988 ◽  
Vol 65 (2) ◽  
pp. 760-766 ◽  
Author(s):  
D. S. Dodd ◽  
P. W. Collett ◽  
L. A. Engel
Keyword(s):  
Flow Rate ◽  
Duty Cycle ◽  
Normal Subjects ◽  
Work Rate ◽  
Inspiratory Flow ◽  
Inspiratory Flow Rate ◽  
Contraction Frequency ◽  
Mouth Pressure ◽  
Resistive Breathing ◽  
Residual Capacity

We examined the combined effect of an increase in inspiratory flow rate and frequency on the O2 cost of inspiratory resistive breathing (VO2 resp). In each of three to six pairs of runs we measured VO2 resp in six normal subjects breathing through an inspiratory resistance with a constant tidal volume (VT). One of each pair of runs was performed at an inspiratory muscle contraction frequency of approximately 10/min and the other at approximately 30/min. Inspiratory mouth pressure was 45 +/- 2% (SE) of maximum at the lower contraction frequency and 43 +/- 2% at the higher frequency. Duty cycle (the ratio of contraction time to total cycle time) was constant at 0.51 +/- 0.01. However, during the higher frequency runs, two of every three contractions were against an occluded airway. Because VT and duty cycle were kept constant, mean inspiratory flow rate increased with frequency. Careful selection of appropriate parameters allowed the pairs of runs to be matched both for work rate and pressure-time product. The VO2 resp did not increase, despite approximately threefold increases in both inspiratory flow rate and contraction frequency. On the contrary, there was a trend toward lower values for VO2 resp during the higher frequency runs. Because these were performed at a slightly lower mean lung volume, a second study was designed to measure the VO2 resp of generating the same inspiratory pressure (45% maximum static inspiratory mouth pressure at functional residual capacity) at the same frequency but at two different lung volumes. This was achieved with a negligibly small work rate.(ABSTRACT TRUNCATED AT 250 WORDS)

Flow rate and duty cycle effects in lysis ofChlamydomonas reinhardtiiusing high-energy pulsed focused ultrasound

2014 ◽  
Vol 135 (6) ◽  
pp. 3632-3638 ◽  
Author(s):  
Grant Riesberg ◽  
Timothy A. Bigelow ◽  
Dan J. Stessman ◽  
Martin H. Spalding ◽  
Linxing Yao ◽  
...  
Keyword(s):  
Flow Rate ◽  
Duty Cycle ◽  
Focused Ultrasound ◽  
High Energy ◽  
Pulsed Focused Ultrasound

scholarly journals Removal of Zinc by Bitter Orange Peels Activated Carbon and Commercially Activated Carbon, a Comparison Study.

2017 ◽  
Vol 5 (1) ◽  
pp. 120-131
Author(s):  
Laith Hamdan Hawal
Keyword(s):  
Activated Carbon ◽  
Removal Efficiency ◽  
Flow Rate ◽  
Treatment Time ◽  
Activated Carbons ◽  
Bitter Orange ◽  
Orange Peels ◽  
Effects Of Ph ◽  
Zinc Concentrations ◽  
Adsorbent Materials

 In this study, a comparison between using activated carbon prepared from bitter orange peels (BOAC) and a common commercially activated carbon (CAC), which is brought from the market, as adsorbent materials. This study was designed to find out which of these two activated carbons is more effective in the removal of zinc from waste water. This work examines the use of bitter orange peels, which are available as waste in local markets and in household garbage as an alternative presage to prepare an activated carbon by using (H2SO4) as activating reagent. The effects of pH, initial zinc concentrations, treatment time, adsorbent media bed height and the flow rate of simulated synthetic aqueous solution (SSAS) on the removal efficiency of zinc were all studied under 24oC The results indicated that the removal efficiency of zinc increases with decreasing in pH of SSAS. When the initial concentration of zinc increases in SSAS, the removal efficiency of zinc was decreased. The study proved that the increasing of contact time leads to greater removal efficiency. When the height of adsorbent media in fixed column increases, the removal efficiency was increased. The experiments also showed that the removal efficiency of zinc from the SSAS increased, when the flow rate decreased. It could be concluded from this work that (BOAC) is better than (CAC) as an adsorbent materials in the removal of zinc; with a removal efficiency of (90%, 86%), respectively

scholarly journals BURNING MODES OF A BIPOLAR PULSED DISCHARGE IN CO2

2020 ◽  
pp. 159-164
Author(s):  
V.A. Lisovskiy ◽  
S.V. Dudin ◽  
M.M. Vusyk ◽  
V.D. Yegorenkov
Keyword(s):  
Duty Cycle ◽  
Voltage Drop ◽  
Current Mode ◽  
High Current ◽  
Pulsed Discharge ◽  
Frequency Range ◽  
High Duty Cycle ◽  
Cycle Amplitude ◽  
Self Bias ◽  
Voltage Axis

We have studied the burning modes of the bipolar pulsed discharge in CO2 within the frequency range between 20 and 300 kHz and the duty cycle of 11...97 %. The current and voltage waveforms within the pressure range between 0.1 to 1 Torr were registered. We have established that the duty cycle values may affect the axial structure of the discharge considerably causing the voltage drop redistribution across the electrodes. The bipolar pulsed discharge may burn in a high-current mode (with cathode sheaths near every electrode) as well as in a low-current one (with a low discharge current and weak glow). The transition between these modes may be observed at high duty cycle values. We have found that one may make a shift of the complete oscilloscope voltage pattern higher or lower along the voltage axis and produce a self-bias constant voltage the value and sign of which depend on the duty cycle, amplitude and frequency of the applied voltage.

scholarly journals Hemodialysis biocompatibility mathematical models to predict the inflammatory biomarkers released in dialysis patients based on hemodialysis membrane characteristics and clinical practices

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Amira Abdelrasoul ◽  
Heloisa Westphalen ◽  
Shaghayegh Saadati ◽  
Ahmed Shoker
Keyword(s):  
Molecular Docking ◽  
Clinical Data ◽  
Flow Rate ◽  
Treatment Time ◽  
Morphological Characteristics ◽  
Operating Conditions ◽  
Inflammatory Biomarkers ◽  
Membrane Properties ◽  
Clinical Practices ◽  
Membrane Materials

AbstractChronic kidney disease affects millions of people around the globe and many patients rely on hemodialysis (HD) to survive. HD is associated with undesired life-threatening side effects that are linked to membrane biocompatibility and clinical operating conditions. The present study develops a mathematical model to predict the inflammatory biomarkers released in HD patients based on membrane morphology, chemistry, and interaction affinity. Based on the morphological characteristics of two clinical-grade HD membrane modules (CTA and PAES-PVP) commonly used in Canadian hospitals, a molecular docking study, and the release of inflammatory cytokines during HD and in vitro incubation experiments, we develop five sets of equations that describe the concentration of eight biomarkers (serpin/antithrombin-III, properdin, C5a, 1L-1α, 1L-1β, C5b-9, IL6, vWF). The equations developed are functions of membrane properties (pore size, roughness, chemical composition, affinity to fibrinogen, and surface charge) and HD operating conditions (blood flow rate, Qb, and treatment time, t). We expand our model based on available clinical data and increase its range of applicability in terms of flow rate and treatment time. We also modify the original equations to expand their range of applicability in terms of membrane materials, allowing the prediction and validation of the inflammatory response of several clinical and synthesized membrane materials. Our affinity-based model solely relies on theoretical values of molecular docking, which can significantly reduce the experimental load related to the development of more biocompatible materials. Our model predictions agree with experimental clinical data and can guide the development of novel materials and support evidence-based membrane synthesis of HD membranes, reducing the need for trial-and-error approaches.

scholarly journals Plasma Degradation of Pesticides on the Surface of Corn and Evaluation of Its Quality Changes

2021 ◽  
Vol 13 (16) ◽  
pp. 8830
Author(s):  
Hongxia Liu ◽  
Dingmeng Guo ◽  
Xinxin Feng
Keyword(s):  
Plasma Treatment ◽  
Flow Rate ◽  
Treatment Time ◽  
Starch Content ◽  
Air Flow ◽  
Acid Value ◽  
Quality Changes ◽  
Air Flow Rate ◽  
Acceptable Range ◽  
Significant Difference

Plasma is a surface decontamination tool that is widely used in the food fields for pesticide degradation. In this study the effect of plasma on pesticide elimination from the surface of corn and the corn quality changes were tested as functions of power, air flow rate, treatment time, and frequency. Results indicated that plasma treatment for 60 s at 1000 mL·min−1 air flow rate, power of 20 W, and frequency of 1200 Hz, achieved the largest degradation efficiency up to 86.2% for chlorpyrifos and 66.6% for carbaryl, both of which were below the maximum residues limit of grains. Most importantly, after plasma treatment, there was a remarkable decrease (p < 0.05) in moisture content and starch content for treated corn compared with control. The acid value for treated corn showed a prominent increase (p < 0.05), but within the acceptable range of the standard. The vitamin B2 content of treated corn did not show a significant difference (p > 0.05). All results of this study demonstrated that plasma treatment is a promising technology with the ability to remove pesticide residues on corn while maintaining its quality within acceptable limits.

Water Modeling Study on Removal of Inclusions in RH Degasser

2013 ◽  
Vol 423-426 ◽  
pp. 225-229
Author(s):  
Chun Jie Yang ◽  
Fu Ping Tang ◽  
Tao He
Keyword(s):  
Flow Rate ◽  
Gas Flow ◽  
Influence Factor ◽  
Treatment Time ◽  
Similarity Theory ◽  
Removal Rate ◽  
Nacl Solution ◽  
Gas Flow Rate ◽  
Vacuum Refining ◽  
Optimal Values

A physical model was established according to the similarity theory to simulate the real 175t RH-TB vacuum refining device. Liquid steel is simulated by Nacl solution, the air is approximate argon and polypropylene simulate inclusions. The influence regularity of treatment time ,lift gas flow rate and submersion depth of snorkels on the inclusions removal rate have been discussed, the optimal values for each influence factor have been found and can be used in optimizing the refining technology.

Sign in / Sign up

Export Citation Format

Share Document