Effect Of Squeeze Research Articles

Effect of squeeze, homogenization, and freezing treatments on particle diameter and rheological properties of palygorskite

The natural palygorskite exist as aggregates or bundles via weak electrostatic and van der Waals interactions. A new method for effective disaggregation of bundles was developed via freezing combined with squeeze and homogenization processes. In this work, the effects of squeeze, homogenization, and freezing treatments on particle size and rheological properties of palygorskite were investigated systematically by particle diameter distribution, steady shear, and linear oscillatory measurements. The influences of squeezing times, homogenization pressure, and freezing time on shear stress and shear modulus were studied in detail. The association capacity of rods in the obtained suspensions was discussed according to a power law of the form Y=kyCn. The correlation among the dispersion of palygorskite, the aspect ratio of the rods, and the rheological properties was discussed. The diameter distribution changed from 4.3 to 3.0μm of natural palygorskite to 1.8μm of sample squeezed for two times, frozen at −18°C for 4h, and homogenized at 10MPa. The suspension with higher shear stress and shear modulus was obtained after squeezed for three times and homogenized at 30MPa.

Effect of T6 Heat Treatment in the Microstructure and Mechanical Properties of A356 Reinforced with Nano Al2O3 Particles by Combination Effect of Stir and Squeeze Casting

Hypoeutectic aluminum silicon alloys as (A356) exhibit several specific and interesting properties that qualify them to be used in many automotive and aeronautical applications, aluminum matrix composites have good physical and mechanical properties, when reinforced with nano sized Al2O3 particle, they have high tensile, compressive and fatigue strengths along with superior wear resistance and thermal stability. In this work, the number of cast samples of A356 alloy was prepared by combination effect of stir and squeeze casting, specially designed and built furnace unit allowing for the addition of Al2O3 nano- particles (30nm). The percentage inclusions were varied from 0.5 to 1.5wt% into the molten Al-Si alloy in the liquid state with stirring at 400rpm and squeeze casting at 750̊C and pressure of 600MPa. The microstructural features and the mechanical properties of the as cast and T6 heat treated samples were investigated. The results obtained in the work showed enhance in the mechanical properties of the Al2O3 nano-dispersed alloys. Optical microscopic examination revealed uniform distribution of nano particles. Measurements of hardness, compressive strength and double shear strength showed an increase with increase in percentage addition of these nano particles.

Transvaginal three‐dimensional ultrasound: a method of studying anal anatomy and function

To explore the possibility of using transvaginal 3D ultrasound as a method of assessing the compartments of the anal canal during rest, to determine the effect of squeeze, and to compare these findings with those obtained using the endoanal technique in the same women. Transvaginal 3D ultrasound was used in a cross-sectional study measuring the anal mucosa and sphincters during rest and squeeze in 20 nulligravida women, comparing the results with those of endoanal measurements. Measurements were also performed of the anal mucosa, anorectal curvature (ARC), and anovaginal angle (AVA) and distance (AVD). Volume measurements of the anal mucosa were only possible using transvaginal ultrasound. The mean volume of the anal canal using the transvaginal technique was 7.93 (SD 2.26) and 7.34 (1.54) cm(3) during rest and squeeze, respectively (P = 0.082). The ARC became more acute (3.46 vs. 4.12°/mm, P = 0.031) during squeeze and AVA increased (31.7° vs. 35.8°, P = 0.010). The volume of the anal mucosa (3.12 cm(3)) did not change (P = 0.193), but was distorted during squeeze at the level of the puborectalis sling (P < 0.001 for upper cross-section and diameter). The anal canal was 1 cm longer (P < 0.001), the IAS volume larger (2.97 and 2.08 cm(3), P = 0.003), and the EAS volume smaller (1.85 and 3.96 cm(3), P < 0.001) using the 3D transvaginal technique compared with the endoanal measurements at rest, with similar differences observed on squeeze. In contrast to the endoanal method, transvaginal 3D ultrasound provides a complete assessment of the anal canal, including the mucosa. This method seems suitable for functional studies such as in the present one, which shows that voluntary squeeze increases the angulation of the anal canal and distorts the bowel cross-section at the level of the puborectal muscle.

An MLS-based cartoon deformation

We present an image deformation method driven by skeleton; it is based on MLS deformation algorithm (Schaefer et al. in SIGGRAPH, vol. 25, pp. 533–540, 2006). We improve the MLS deformation by defining a new weight function based on skeleton. Being different from the weight function based on control points, our weight function has benefited from the shape information of undeformed object and keeps deformation local, therefore our method can achieve a realistic effect. In cartoon video, we propose a new method to track the skeleton in the video, to build new origin skeleton and new target skeleton on each frame, and to apply our image deformation method to each frame and maintain spatiotemporal consistency. Results demonstrate that our method is able to decrease the effect of squeeze and use less control points.

OC30.02: Changes in the female anal channel during voluntary squeeze assessed by vaginal ultrasound

Objective: Several mechanisms are believed to be in play maintaining anal continence, one of them being voluntary squeezing using the pelvic muscles. Here we study the effect of squeeze on the anal channel position and dimensions. Method: 20 healthy 0-gravida and 24 women with anal incontinence were recruited after written consent for 3D vaginal ultrasound measurements of angles and diameters during rest and squeeze. The anovaginal angle was defined as the angle between the posterior vaginal wall and the anterior wall of the channel assessed in a sagittal section. The anorectal angle was defined as the angle between the posterior wall of the anal channel and that of the rectal wall above the level of the puborectal muscle. Diameter and area of the mucosa were measured in the middle of the anal channel (lower level) and at the level of the puborectal muscle (upper level). Results: The 0-gravida had a mean age of 26 years with an incontinence score 0 on a scale 0–24. The incontinent women had a mean age of 59 years and their score was mean 11 (range 3–22). The ultrasound measurement results are presented in the table. Conclusion: Voluntary squeeze augments the bend of the anal and rectal tube at the level of the puborectal muscle and compresses the mucosal cuff at this level in young 0-gravida women. In incontinent women of a higher age, the anal tube is straighter, the mucosal cuff in the lower anal channel is smaller, and the effect of squeeze is less prominent or lacking.

OC30.03: The impact of first delivery on the levator hiatus and the urogenital hiatuxs

Objective: Several mechanisms are believed to be in play maintaining anal continence, one of them being voluntary squeezing using the pelvic muscles. Here we study the effect of squeeze on the anal channel position and dimensions. Method: 20 healthy 0-gravida and 24 women with anal incontinence were recruited after written consent for 3D vaginal ultrasound measurements of angles and diameters during rest and squeeze. The anovaginal angle was defined as the angle between the posterior vaginal wall and the anterior wall of the channel assessed in a sagittal section. The anorectal angle was defined as the angle between the posterior wall of the anal channel and that of the rectal wall above the level of the puborectal muscle. Diameter and area of the mucosa were measured in the middle of the anal channel (lower level) and at the level of the puborectal muscle (upper level). Results: The 0-gravida had a mean age of 26 years with an incontinence score 0 on a scale 0–24. The incontinent women had a mean age of 59 years and their score was mean 11 (range 3–22). The ultrasound measurement results are presented in the table. Conclusion: Voluntary squeeze augments the bend of the anal and rectal tube at the level of the puborectal muscle and compresses the mucosal cuff at this level in young 0-gravida women. In incontinent women of a higher age, the anal tube is straighter, the mucosal cuff in the lower anal channel is smaller, and the effect of squeeze is less prominent or lacking.

Reflective practice in practice

Reflective practice in practice

Accelerator mass spectrometry (AMS) of the inhibitory effect of six dietary constituents on nicotine-hemoglobin adduction in mice

Accelerator mass spectrometry (AMS) is an ultra-sensitive method to monitor and trace the environmental exposure levels of 14C-labeled molecules in vivo. Nicotine [3-(1-methyl-2-pyrrolidinyl)-pyridine], a major alkaloid in tobacco products, has proven to be a potential genotoxic compound. Using 14C-labeled nicotine and AMS, we have investigated the inhibitory effect of curcumin, garlic squeeze, grapeseed extract, tea polyphenols, vitamin C and vitamin E, respectively, on nicotine-hemoglobin (Hb) adduction in vivo. The results demonstrated that these dietary constituents induced remarkable decrease of nicotine-Hb adducts. The inhibitory fact may afford an important clue of the chemoprevention of the potential nicotine-induced carcinogenesis.

Compression of a Single Transverse Ridge in a Circular Elastohydrodynamic Contact

A detailed experimental study has been made of the behavior of a 100 nm high transversely oriented ridge in an elastohydrodynamic (EHD) contact. Ultra-thin film interferometry has been used to measure film profiles accurately over a very wide range of lubricant film thicknesses, from a few nanometers up to nearly one micron. This enables the recovery of the amplitude of the inlet perturbation geometry with increasing EHD film thickness to be quantified and compared with numerical predictions. In pure rolling under very thin film conditions, corresponding to a smooth surface EHD film thickness of 10 nm, the surfaces near the ridge were squashed down, leading to a constriction in the film of only about 9 percent of the height of the un-deformed ridge. As the EHD film thickness increased, this deformation recovered until the ridge constriction regained about 90 percent of its original height at film thicknesses of about 1 μm. However this relatively rapid recovery only occurred in pure rolling and is attributed to the local perturbation of film convergence which the ridge generates while in the inlet region. This propagates through the contact at the mean speed of the surfaces and—in pure rolling—acts to diminish the effect of local squeeze. When sliding was present, the ridge remained almost fully deformed even when the mean film thickness was as much as twice the height of the original ridge. In this case, the ridge travels through the contact at a different speed from the mean of the two surfaces. The consequent decoupling of the ridge and the convergence perturbation results in a large local pressure due to squeeze which acts to inhibit recovery of the ridge. The general trend of the behavior of the lubricated ridge is shown to be in good agreement with earlier theoretical results.

Bank-Specific Characteristics and Monetary Policy Transmission: The Case of Italy

This paper tests cross-sectional differences in the effectiveness of the bank lending channel of monetary policy in Italy from 1986 to 1998 using a panel approach. After a monetary tightening the decrease in deposits subject to reserve requirements is sharper for those banks that have less incentive to shield the effect of a monetary squeeze: small banks characterized by a higher ratio of deposits to loans and well-capitalized banks that have a greater capacity to raise other forms of external funds. As to lending, size does not affect the banks' reaction to a monetary policy impulse. This can be explained by a closer customer relationship, which provides an incentive for small banks, which are more liquid on average, to smooth the effects of a tightening on credit supplied. Banks' liquidity is the most significant factor enabling them to attenuate the effect of a decrease in deposits on lending.

Suppression of bladder instability by penile squeeze.

The effect of penile squeeze upon bladder instability was examined in 20 males and the results compared with those of anal dilatation. An uninhibited contraction of the bladder was successfully suppressed by squeezing the glans penis in 17 out of 20 patients and by dilating the anal sphincter in 20. It is concluded that this mechanical stimulus, when given to the glans penis of a normal man suffering from bladder instability, suppresses the detrusor contraction during the contracting phase but does not affect bladder tonus during the noncontracting phase.

Consequences of Eyelid Squeezing on Intraocular Pressure

We investigated the effect of a forcible eyelid squeeze (two-second squeeze and two-second rest) over one minute, on intraocular pressure in volunteer groups of normal volunteers, ocular hypertensive and glaucoma patients, and those with a family history of glaucoma. The normal volunteers fell into two groups: responders and nonresonders, with the responders showing about a 2-mm Hg decrease and the nonresponders a small increase in intraocular pressure. It was possible to arrange the groups into an order dependent upon the change in intraocular pressure induced by eyelid squeezing; normal responders (-1.98 mm Hg), family history of glaucoma (-0.48 mm Hg), ocular hypertensive patients (-0.07 mm Hg), normal nonresponders (+ 0.04 mm Hg) and glaucoma patients (taking medication) (+ 0.25 mm Hg). Correlation of disease entity with other ocular factors such as intraocular pressure and total outflow facility was poor.

Determination of rock squeeze potential for underground power projects : Lee, C F; Klym, T W Engng Geol, V12, N2, July 1978, P181–192

Abstract Post-construction movements of the surrounding rock mass into underground openings often result in a gradual (and in some cases excessive) build-up of load on liners and other supporting structures. It is suggested that the time rate of “swell” measured on fresh cores be used as an index in assessing the liability of underground structures to this adverse effect of rock squeeze. The experimental aspects of determining such an index are discussed in this paper, along with their application to the design of underground structures in “squeezing” rock.

Determination of rock squeeze potential for underground power projects

Post-construction movements of the surrounding rock mass into underground openings often result in a gradual (and in some cases excessive) build-up of load on liners and other supporting structures. It is suggested that the time rate of “swell” measured on fresh cores be used as an index in assessing the liability of underground structures to this adverse effect of rock squeeze. The experimental aspects of determining such an index are discussed in this paper, along with their application to the design of underground structures in “squeezing” rock.

A Study of the Lubrication and Dynamics of Geometrically Perfect, Lightly Loaded, Cylindrical Roller Bearings with Particular Reference to Shaft Loci

The principal objective of this paper is to ascertain and quantify the cyclic movement of the centre of a shaft in a geometrically perfect, lubricated, cylindrical roller bearing exhibiting initial clearance and subjected to a light and steady load. The movement may be important in relation to the accuracy of location of shafts in roller bearings, and it is shown that a detailed consideration of the rolling element assembly predicts some interesting effects. The study also covers more conventional features of bearing performance such as lubricant film thickness and coefficient of friction, and shows the effect of squeeze to be negligible under steady bearing loads.