Acoustic Cavitation Behavior in Isopropyl Alcohol Added Cleaning Solution

2012 ◽  
Vol 195 ◽  
pp. 169-172
Author(s):  
Bong Kyun Kang ◽  
Ji Hyun Jeong ◽  
Min Su Kim ◽  
Hong Seong Sohn ◽  
Ahmed A. Busnaina ◽  
...  
Keyword(s):  
Growth Rate ◽  
Physical Properties ◽  
Bubble Growth ◽  
Bubble Collapse ◽  
Particle Removal ◽  
Factors Affecting ◽  
Ultrasound Field ◽  
Cavitation Threshold ◽  
The Difference ◽  
Cavitation Behavior

As the semiconductor manufacturing technology for ultra-high integration devices continue to shrink beyond 32 nm, stringent measures have to be taken to get damage free patterns during the cleaning process. The patterns are no longer cleaned with the megasonic (MS) irradiation in the advanced device node because of severe pattern damages caused by cleaning. Recently, several investigations are carried out to control the cavitation effects of megasonic to reduce the pattern damages. The mechanism of damage caused by an unstable acoustic bubble motion was mainly attributed to the high sound pressure associated with violent bubble collapse [1]. In order to characterize the dominant factors affecting the cavitation, MS cleaning was conducted with various dissolved gas concentrations in water. It was reported that the cavitation phenomena relating to particle removal efficiency (PRE) and pattern damage were considerably changed with the addition of a specific gas [2]. This changing behavior may be due to the difference in the physical properties of dissolved gases associated with acoustic bubble growth rate as a function of their concentration. In particular, cavitation effects induced during MS cleaning was controlled by adjusting the acoustic bubble growth rate. Also the change of bubble growth rate is well explained by both rectified diffusion for single bubble and bubble coalescence for multi-bubble, respectively. Similarly, it is well-known that surface active solute (SAS) in the ultrasound field plays an important role in controlling the cavitation effects. A detailed explanation of the acoustic bubble growth rate, cavitation threshold and their relationship with various types of SAS and concentration of biomedical and chemical reactions perspective have been reported elsewhere [3,4]. Their studies demonstrated that the change of cavitation effects depends not only on the chain length of alcohol in the solution but also on the physical properties such as surface tension and viscosity of SAS solutions.

Effects of Bubble Growth and Solidification Rate on Pore Formation in Solid

2012 ◽  
Author(s):  
P. S. Wei ◽  
S. Y. Hsiao
Keyword(s):  
Growth Rate ◽  
Contact Angle ◽  
Solidification Front ◽  
Bubble Growth ◽  
Pore Formation ◽  
Solidification Rate ◽  
Bubble Radius ◽  
Abel Equation ◽  
Spherical Cap ◽  
Factors Affecting

The shapes of a pore in solid resulted from entrapment of a tiny bubble by a solidification front are predicted in this work. Pore formation and its shape in solid are one of the most critical factors affecting properties and microstructure, in materials. For simplicity without loss of generality, the tiny bubble is considered to have a spherical cap. From a geometrical analysis, the contact angle of the bubble cap on the solidification front or the pore shape in solid is found to be governed by the Abel equation of the first kind. The pore becomes closed by imposing a finite bubble growth rate-to-solidification rate ratio which can produce a minimal bubble radius at the contact angle of 90 degrees. Closure of a pore resulted from a greater solidification rate than bubble growth rate, as accepted in the literature, is incorrect.

scholarly journals The effects of “Fangcang, Huoshenshan, and Leishenshan” hospitals and environmental factors on the mortality of COVID-19

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e9578
Author(s):  
Yuwen Cai ◽  
Tianlun Huang ◽  
Xin Liu ◽  
Gaosi Xu
Keyword(s):  
Growth Rate ◽  
Air Quality ◽  
Quality Index ◽  
Test Statistic ◽  
Factors Affecting ◽  
Before And After ◽  
The Difference ◽  
Student’S T ◽  
Novel Coronavirus ◽  
Student’S T Test

Background In December 2019, a novel coronavirus disease (COVID-19) broke out in Wuhan, China; however, the factors affecting the mortality of COVID-19 remain unclear. Methods Thirty-two days of data (the growth rate/mortality of COVID-19 cases) that were shared by Chinese National Health Commission and Chinese Weather Net were collected by two authors independently. Student’s t-test or Mann-Whitney U test was used to test the difference in the mortality of confirmed/severe cases before and after the use of “Fangcang, Huoshenshan, and Leishenshan” makeshift hospitals (MSHs). We also studied whether the above outcomes of COVID-19 cases were related to air temperature (AT), relative humidity (RH), or air quality index (AQI) by performing Pearson’s analysis or Spearman’s analysis. Results Eight days after the use of MSHs, the mortality of confirmed cases was significantly decreased both in Wuhan (t = 4.5, P < 0.001) and Hubei (U = 0, P < 0.001), (t and U are the test statistic used to test the significance of the difference). In contrast, the mortality of confirmed cases remained unchanged in non-Hubei regions (U = 76, P = 0.106). While on day 12 and day 16 after the use of MSHs, the reduce in mortality was still significant both in Wuhan and Hubei; but in non-Hubei regions, the reduce also became significant this time (U = 123, P = 0.036; U = 171, P = 0.015, respectively). Mortality of confirmed cases was found to be negatively correlated with AT both in Wuhan (r =  − 0.441, P = 0.012) and Hubei (r =  − 0.440, P = 0.012). Also, both the growth rate and the mortality of COVID-19 cases were found to be significantly correlated with AQI in Wuhan and Hubei. However, no significant correlation between RH and the growth rate/mortality of COVID-19 cases was found in our study. Conclusions Our findings indicated that both the use of MSHs, the rise of AT, and the improvement of air quality were beneficial to the survival of COVID-19 patients.

scholarly journals Physical Properties of Modern Reciprocal Endodontic Systems and Fatigue Failure Testing in Simulated Clinical Conditions

2021 ◽  
Vol 11 (23) ◽  
pp. 11160
Author(s):  
Alexandr Jusku ◽  
Jan Tomáštík ◽  
Lukáš Václavek ◽  
Petr Jirásek ◽  
Ľuboš Harvan ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Physical Properties ◽  
Cross Section ◽  
Thermal Processing ◽  
Fatigue Testing ◽  
Cyclic Fatigue ◽  
Factors Affecting ◽  
3D Microscopy ◽  
The Difference ◽  
Clinical Conditions

Instrument fracture ranks among the most crucial complications during the endodontic treatment of a tooth. In order to better understand the practical limits of the instrument, the relation between the cyclic fatigue resistance and physical properties such as hardness, modulus of elasticity, creep and surface roughness were explored. Cyclic fatigue testing in an artificial root canal at intracanal temperature, nanoindentation and 3D microscopy were used for evaluation of four commonly used thermomechanically treated NiTi endodontic instruments (Unicone Plus 6/025, Unicone 6/025, Reciproc Blue R25 and WaveOne Gold Primary). Cyclic fatigue results were analyzed using the Kruskal–Wallis, Mann–Whitney and Bonferroni corrections. The wear resistance of Unicone 6/025 instruments was significantly lower compared to all other instruments (p < 0.05). WaveOne Gold Primary was significantly less resistant than Unicone Plus 6/025 and Reciproc Blue R25, while the difference between Reciproc Blue R25 and Unicone Plus 6/025 was insignificant (p > 0.05). These results are in correlation with measurements of local mechanical properties (hardness, elastic modulus and their ratios H/E and H3/E2). Even though surface roughness, area of cross-section and shape of instruments are important factors affecting instruments behavior, thermal processing appears to be the most important.

A quantitative evaluation of some factors affecting the non-fatty solids of cow's milk

1960 ◽  
Vol 27 (1) ◽  
pp. 19-32 ◽  
Author(s):  
W. H. Alexander ◽  
F. B. Leech
Keyword(s):  
Cell Count ◽  
Residual Effect ◽  
Clinical Mastitis ◽  
High Cell ◽  
Factors Affecting ◽  
Stage Of Lactation ◽  
Cell Counts ◽  
Satisfactory Analysis ◽  
The Difference ◽  
Image Position

SummaryTen farms in the county of Durham took part in a field study of the effects of feeding and of udder disease on the level of non-fatty solids (s.n.f.) in milk. Statistical analysis of the resulting data showed that age, pregnancy, season of the year, and total cell count affected the percentage of s.n.f. and that these effects were additive and independent of each other. No effect associated with nutritional changes could be demonstrated.The principal effects of the factors, each one freed from effects of other factors, were as follows:Herds in which s.n.f. had been consistently low over a period of years were compared with herds in which s.n.f. had been satisfactory. Analysis of the data showed that about 70% of the difference in s.n.f. between these groups could be accounted for by differences in age of cow, stage of lactation, cell count and breed.There was some evidence of a residual effect following clinical mastitis that could not be accounted for by residual high cell counts.The within-cow regression of s.n.f. on log cell count calculated from the Durham data and from van Rensburg's data was on both occasions negative.The implications of these findings are discussed, particularly in relation to advisory work.

A Model of Wheat Grain Growth and Its Applications to Different Temperature and Carbon Dioxide Levels

1995 ◽  
Vol 22 (5) ◽  
pp. 843 ◽  
Author(s):  
YP Wang ◽  
RM Gifford
Keyword(s):  
Growth Rate ◽  
Grain Growth ◽  
Temperature Response ◽  
Rate Sensitivity ◽  
Temperature Sensitive ◽  
Potential Growth ◽  
Carbon Supply ◽  
The Difference ◽  
Carbon Dioxide Levels ◽  
Kernel Growth

Kernel growth after anthesis is simulated as a function of the potential kernel growth rate, current photosynthate production and mobilisation of stored reserves. The potential growth rate of the kernel is simulated as two temperature-sensitive processes, cell production and cell growth. The difference between the potential and actual growth rates of the kernel depends on the carbon supply to the free space of the kernel endosperm, while the carbon supply is itself affected by the actual kernel growth rate. Sensitivity analysis showed that the growth rate of the grain per plant is most sensitive to the potential growth rate of the kernel and number of kernels per plant. This model is able to simulate the observed rates of grain growth and leaf senescence from anthesis to physiological maturity for wheat plants grown in two CO2 concentrations. The simulated temperature response of grain growth agrees well with the experimenal observations.

Effect of growth rate on the structure and physical properties of Mo doped ZnO films

2016 ◽  
Vol 99 ◽  
pp. 175-181 ◽  
Author(s):  
Guifeng Chen ◽  
Xiaoli Zhao ◽  
Hui Zhang ◽  
Feifei Liu ◽  
Yong Wang ◽  
...  
Keyword(s):  
Growth Rate ◽  
Physical Properties ◽  
Zno Films ◽  
Doped Zno

Determination Of Factors Affecting Father-Baby Attachment

2021 ◽  
Vol 6 (14) ◽  
pp. 1-7
Author(s):  
Emine Serap ÇAĞAN ◽  
Birsen KARACA SAYDAM ◽  
Sinem GÜLÜMSER ATEŞ ◽  
Rabia EKTİ GENÇ ◽  
Esin ÇEBER TURFAN
Keyword(s):  
Cross Sectional Study ◽  
Study Data ◽  
Cross Sectional ◽  
Infant Attachment ◽  
Factors Affecting ◽  
Attachment Figure ◽  
Gynecology And Obstetrics ◽  
Significant Difference ◽  
Package Program ◽  
The Difference

Introduction: The primary attachment figure is mostly defined as the mother, and studies focus on the mother. However, in many babies, basic attachment is just as good with the father as with the mother. It is seen that there are very few studies in the literature investigating the correlations of father-infant attachment relationships.. The aim of this study is to determine the father-infant attachment status and to determine the factors affecting attachment. Method: The population of the cross-sectional study consisted of the spouses of all puerperant women hospitalized in the Gynecology and Obstetrics Clinic between September 1, 2018 and October 1, 2018. The sample size consisted of 156 fathers who agreed to participate in the study. Father identification form and father-infant attachment scale were used to collect the study data. The analysis of the data obtained from the research was carried out on the computer using the SPSS 16.0 package program. Results: 156 fathers participated in the study. The mean age of the fathers is 33.64±6.49, and 38.5% of them have a bachelor's degree. 91.0% of fathers stated that they felt ready for fatherhood. The fathers' Father-Infant Attachment Scale mean score was 82.60±7.72 In the analysis, the difference between the variables and the total score of the scale was found to be statistically insignificant (p>0.05). Discussion and Conclusion: At the end of the study, the bonding process of fathers participating in the study with their babies and the factors affecting this process were evaluated and it was seen that the father-infant attachment scale mean scores of the fathers participating in the study were high and were similar to other studies. In addition, when the basic factors affecting father-infant attachment were compared with the attachment scale mean score, it was found that there was no statistically significant difference.

Occurrence and die-off of indicator organisms in the sediment in two constructed wetlands

2001 ◽  
Vol 44 (11-12) ◽  
pp. 223-230 ◽  
Author(s):  
T.A. Stentström ◽  
A. Carlander
Keyword(s):  
Constructed Wetlands ◽  
Municipal Wastewater ◽  
Full Scale ◽  
Water Phase ◽  
Fecal Coliforms ◽  
Main Concern ◽  
Particle Removal ◽  
Stormwater Treatment ◽  
Indicator Organisms ◽  
Factors Affecting

The interest in constructed wetlands for municipal wastewater and stormwater treatment has recently increased but data for the reduction efficiency of indicator organisms are often restricted to the water phase. In a full-scale wastewater wetland in Sweden fecal coliforms and enterococci were reduced by 97-99.9% and coliphages by approximately 70%. The factors affecting the reduction are however less well understood. In two full-scale wetlands, for stormwater and wastewater treatment, an assessment has been done of the particle associated fraction of indicator organisms. No significant differences in the particle-associated numbers were seen between the inlet and the outlet of the wetlands, but the amounts of sedimenting particles varied between the two sites. In the stormwater wetland the amount of sedimenting particles at the outlet was 3% of the amount at the inlet, while the wastewater wetland had much lower particle removal efficiency. The reduction of suspended particles seems to be the main factor for bacterial elimination from the water phase, governed by vegetation and design. In the sediment, survival of presumptive E.coli, fecal enterococci, Clostridium and coliphages were long with T90-values of 27, 27, 252 and 370 days, respectively. The organisms can however be reintroduced by resuspension. Viruses in the water phase may be of main concern for a risk assessment of receiving waters.

scholarly journals On the statics and dynamics of fully confined bubbles

2017 ◽  
Vol 827 ◽  
pp. 194-224 ◽  
Author(s):  
Olivier Vincent ◽  
Philippe Marmottant
Keyword(s):  
Bubble Growth ◽  
Liquid Velocity ◽  
Plant Cells ◽  
Natural Oscillation ◽  
Bubble Collapse ◽  
Statics And Dynamics ◽  
Stability Phase Diagram ◽  
Oscillation Dynamics ◽  
Solid Walls ◽  
Gas Compressibility

We investigate theoretically the statics and dynamics of bubbles in fully confined liquids, i.e. in liquids surrounded by solid walls in all directions of space. This situation is found in various natural and technological contexts (geological fluid inclusions, plant cells and vessels, soil tensiometers, etc.), where such bubbles can pre-exist in the trapped liquid or appear by nucleation (cavitation). We focus on volumetric deformations and first establish the potential energy of fully confined bubbles as a function of their radius, including contributions from gas compressibility, surface tension, liquid compressibility and elastic deformation of the surrounding solid. We evaluate how the Blake threshold of unstable bubble growth is modified by confinement and we also obtain an original bubble stability phase diagram with a regime of liquid superstability (spontaneous bubble collapse) for strong confinements. We then calculate the liquid velocity field associated with radial deformations of the bubble and strain in the solid, and we predict large deviations in the kinematics compared to bubbles in extended liquids. Finally, we derive the equations governing the natural oscillation dynamics of fully confined bubbles, extending Minnaert’s formula and the Rayleigh–Plesset equation, and we show that the compressibility of the liquid as well as the elasticity of the walls can result in ultra-fast bubble radial oscillations and unusually quick damping. We find excellent agreement between the predictions of our model and recent experimental results.

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