Relationship of Particle Content and Size of Spherical Silica with the Flowability of Epoxy Molding Compounds for Large-Scale Integrated Circuits Packaging

The melting viscosities of different kinds of epoxy resins have been investigated in this paper. The results showed that tetramethyl biphenyl epoxy resin(TMBP) has very low melting viscosity(0.02Pa•s at 150°C) and can be blended with ortho-cresol novolac epoxy resin(ECN) in order to decrease the melting viscosity of epoxy molding compound(EMC). When the content of TMBP in the blend of ECN/TMBP was up to 40wt%, the viscosity of the blend decreased to 0.15 Pa•s from 0.8 Pa•s of ECN. In addition, the effects of the content, particle size of silica on the flowability of EMC have been researched systematically in the paper. The results showed that the melting viscosity of EMC increased greatly with the filling increasing of silica, and the particle size and the match of silica with different particle diameter had markedly influenced on the flowability of EMC. The melting viscosity of system with higher filling content of silica changed complicatedly with the increasing of shear rate, i.e., the viscosity of the system decreased with the increasing of shear rate in the range of low shear rate, then increased with the increasing of shear rate in the range of high shear rate, but decreased again with the increasing of shear rate in the range of higher shear rate. The system filled by silica with small particle diameter had low melting viscosity at low shear rate and high melting viscosity at high shear rate, but the melting viscosity of the system filled by silica with large particle diameter changed by contraries.

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Whole blood viscosity in the evaluation of thrombogenic milieu in mitral stenosis

Biomarkers in Medicine ◽

10.2217/bmm-2020-0329 ◽

2021 ◽

Vol 15 (3) ◽

pp. 181-190

Author(s):

Elif H Ozcan Cetin ◽

Mehmet S Cetin ◽

Mustafa B Ozbay ◽

Hasan C Könte ◽

Nezaket M Yaman ◽

...

Keyword(s):

Shear Rate ◽

Blood Viscosity ◽

Whole Blood ◽

Mitral Stenosis ◽

High Shear Rate ◽

High Shear ◽

Whole Blood Viscosity ◽

Spontaneous Echo Contrast ◽

Shear Rates ◽

Low Shear

Aim: We aimed to assess the association of whole blood with thromboembolic milieu in significant mitral stenosis patients. Methodology & results: We included 122 patients and classified patients into two groups as having thrombogenic milieu, thrombogenic milieu (+), otherwise patients without thrombogenic milieu, thrombogenic milieu (-). Whole blood viscosity (WBV) in both shear rates were higher in thrombogenic milieu (+) group comparing with thrombogenic milieu (-). WBV at high shear rate and WBV at low shear rate parameters were moderately correlated with grade of spontaneous echo contrast. Adjusted with other parameters, WBV parameters at both shear rates were associated with presence of thrombogenic milieu. Discussion & conclusion: We found that extrapolated WBV at both shear rates was significantly associated with the thrombogenic milieu in mitral stenosis. This easily available parameter may provide additional perspective about thrombogenic diathesis.

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The Simulation of Aggregated Colloids Under Flow

MRS Proceedings ◽

10.1557/proc-289-33 ◽

1992 ◽

Vol 289 ◽

Author(s):

John R. Melrose

Keyword(s):

Shear Rate ◽

Large Scale ◽

Shear Thinning ◽

High Shear ◽

Shear Rates ◽

Rouse Model ◽

High Shear Rates ◽

Structural Breakdown ◽

Large Scale Simulations ◽

Low Shear

AbstractAn overview is given of theories of aggregates under flow. These generally assume some sort of structural breakdown as the shear rate is increased. Models vary with both the rigidity of the bonding and the level of treatment of hydrodynamics. Results are presented for simulations of a Rouse model of non-rigid, (i.e. central force) weakly bonded aggregates. In large scale simulations different structures are observed at low and high shear rates. The change from one structure to another is associated with a change in the rate of shear thinning. The model captures low shear rate features of real systems absent in previous models: this feature is ascribed to agglomerate deformations. Quantitatively, the model is two orders of magnitude out from experiment but some scaling is possible.

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News from the M in CMP - Viscosity of CMP Slurries, a Constant?

MRS Proceedings ◽

10.1557/proc-767-f1.7 ◽

2003 ◽

Vol 767 ◽

Cited By ~ 4

Author(s):

W. Lortz ◽

F. Menzel ◽

R. Brandes ◽

F. Klaessig ◽

T. Knothe ◽

...

Keyword(s):

Particle Size ◽

Shear Rate ◽

Particle Size Distribution ◽

Size Distribution ◽

High Shear Rate ◽

Bet Surface Area ◽

Energy Concentration ◽

High Shear ◽

Polishing Pad ◽

Distribution Shape

AbstractIt is well known and accepted that the viscosity of CMP-slurries has an effect on polishing results. Even though the literature on rheology recognizes that viscosity is not always constant and the slurry can show non-Newtonian behavior or even dilatant effects, all calculations have been performed with constant viscosity.However, the “real” viscosity of a CMP-slurry during polishing can change significantly with shear rate.The typical equipment for viscosity measurement is based on a rotating cylinder or a plate. But even with a plate system it is only possible to reach a shear rate range up to 50,000 1/sec. A calculation of the shear rate between the wafer and the polishing pad is based on a relative velocity of 1 m/sec and a distance between the wafer and the pad of 20 μm; this correlates to a shear rate of 50,000 1/sec. If parts of the polishing pad come closer to the wafer or especially closer to the edge of structures on the wafer (for example 1 μm), the shear rate will increase locally to 1,000,000 1/sec.When the shear rate is high enough, viscosity depends mostly on hydrodynamic factors like viscosity of continuos phase, solids content, particle size, particle size distribution and shape of the particles.The shape of fumed metal oxides is controlled during the synthesis in the flame process. But the slurry-making process is also responsible for particle size distribution, shape of the particle and the high shear rate viscosity of the CMP-slurry.The high shear rate viscosity of different silica slurries in dependence from BET-surface area, used milling energy, concentration and preparation direction was measured in this investigation.

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A semi-infinite hydraulic fracture driven by a shear-thinning fluid

Journal of Fluid Mechanics ◽

10.1017/jfm.2017.900 ◽

2018 ◽

Vol 838 ◽

pp. 573-605 ◽

Cited By ~ 14

Author(s):

Fatima-Ezzahra Moukhtari ◽

Brice Lecampion

Keyword(s):

Shear Rate ◽

Power Law ◽

Hydraulic Fracture ◽

Complex Structure ◽

Shear Thinning ◽

High Shear Rate ◽

Asymptotic Region ◽

High Shear ◽

Confining Stress ◽

Low Shear

We use the Carreau rheological model which properly accounts for the shear-thinning behaviour between the low and high shear rate Newtonian limits to investigate the problem of a semi-infinite hydraulic fracture propagating at a constant velocity in an impermeable linearly elastic material. We show that the solution depends on four dimensionless parameters: a dimensionless toughness (function of the fracture velocity, confining stress, material and fluid parameters), a dimensionless transition shear stress (related to both fluid and material behaviour), the fluid shear-thinning index and the ratio between the high and low shear rate viscosities. We solve the complete problem numerically combining a Gauss–Chebyshev method for the discretization of the elasticity equation, the quasi-static fracture propagation condition and a finite difference scheme for the width-averaged lubrication flow. The solution exhibits a complex structure with up to four distinct asymptotic regions as one moves away from the fracture tip: a region governed by the classical linear elastic fracture mechanics behaviour near the tip, a high shear rate viscosity asymptotic and power-law asymptotic region in the intermediate field and a low shear rate viscosity asymptotic far away from the fracture tip. The occurrence and order of magnitude of the extent of these different viscous asymptotic regions are estimated analytically. Our results also quantify how shear thinning drastically reduces the size of the fluid lag compared to a Newtonian fluid. We also investigate simpler rheological models (power law, Ellis) and establish the small domain where they can properly reproduce the response obtained with the complete rheology.

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Characterizing the Rheology of Methane Hydrate Slurry in a Horizontal Water-Continuous System

SPE Journal ◽

10.2118/195586-pa ◽

2019 ◽

Vol 25 (03) ◽

pp. 1026-1041 ◽

Cited By ~ 17

Author(s):

Baojiang Sun ◽

Weiqi Fu ◽

Zhiyuan Wang ◽

Jianchun Xu ◽

Litao Chen ◽

...

Keyword(s):

Shear Rate ◽

Natural Gas ◽

Methane Hydrate ◽

Shear Thickening ◽

Continuous System ◽

Shear Thinning ◽

High Shear Rate ◽

High Shear ◽

Thickening Behavior ◽

Low Shear

Summary Methane hydrate slurry in a water-continuous system is a significant production issue during pilot explorations for natural gas and natural gas hydrates in a deepwater environment. This work investigated the morphology and rheology of hydrate slurry with hydrate concentrations from 6 to 11% and shear rates from 20 to 700 s−1. Although hydrate slurry is widely considered a pseudoplastic fluid, in our experiment, hydrate slurry exhibited shear-thinning behavior in low-shear-rate conditions and shear-thickening behavior in high-shear-rate conditions. The breakup of agglomerates built up between hydrate particles by shear force induced shear-thinning behavior in low-shear-rate conditions. The collision between monodispersed hydrate particles resulted in shear-thickening behavior in high-shear-rate conditions. The critical shear rate was proposed to describe the transition between the shear-thinning and shear-thickening behaviors of the hydrate slurry, which was a function of the hydrate concentration. Empirical Herschel-Bulkley-type equations were developed to describe the rheology of the hydrate slurry for both conditions.

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Safety of Five Tuina Manipulations in Rats with Deep Vein Thrombosis

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2021/6897124 ◽

2021 ◽

Vol 2021 ◽

pp. 1-10

Author(s):

Ying Zhou ◽

Yumo Zhang ◽

Xiaoyan Zhang ◽

Zhuo Chen ◽

Jian Dong ◽

...

Keyword(s):

Deep Vein Thrombosis ◽

Shear Rate ◽

Strain Rate ◽

Rate Ratio ◽

Plasma Viscosity ◽

High Shear Rate ◽

High Shear ◽

Vein Thrombosis ◽

Deep Vein ◽

Low Shear

Objective. To study the effects of five tuina manipulations in rats with deep vein thrombosis (DVT) and to explore how to safely perform tuina in the treatment of thrombotic diseases. Methods. Seventy-two male Sprague-Dawley (SD) rats were randomly divided into the model, pointing manipulation, plucking manipulation, kneading manipulation, pushing manipulation, and pulling manipulation groups (n = 12). DVT model was established by incomplete ligation. The tuina intervention was started on the next day after modeling and applied once a day 10 times by the manipulation simulators. On the 3rd and 10th days after intervention, respectively, the effects of tuina on thrombosis were evaluated based on thrombus elasticity, blood coagulation, fibrinolytic function and blood rheology with the ultrasound elastography, four coagulation tests, enzyme linked immunosorbent assay (ELISA), and hemorheology tests. Results. In the pointing manipulation group, the strain rate ratio, 6-ketoprostaglandin F1α (6-Keto-PGF1α), and high shear rate were decreased, and the thromboxane B2 (TXB2) content was increased ( P < 0.05 ). In the plucking manipulation group, the D-dimer and 6-Keto-PGF1α contents were increased, prothrombin time (PT) was shortened, and activated partial thromboplastin time (APTT) was activated, and the high shear rate and plasma viscosity were decreased ( P < 0.05 ). In the kneading manipulation group, APTT was shortened, and 6-Keto-PGF1α, high shear rate, and plasma viscosity were decreased ( P < 0.05 ). In the pushing manipulation group, the strain rate ratio, low shear rate, and high shear rate were all decreased ( P < 0.05 ). In the pulling manipulation group, both the strain rate ratio and the low shear rate were decreased ( P < 0.05 ). The 6-Keto-PGF1α changes on the 3rd and 10th days after intervention were opposite in the pushing manipulation group and the pulling manipulation group ( P < 0.05 ). Conclusion. The pointing, pushing, and pulling manipulations seem to be safe in the early period of thrombosis, but the risk is likely to be elevated as the treatment course of intervention increases. The plucking and kneading manipulations potentially have certain risks in the treatment of DVT in rats.

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Whole blood viscosity predicts nondipping circadian pattern in essential hypertension

Biomarkers in Medicine ◽

10.2217/bmm-2020-0249 ◽

2020 ◽

Vol 14 (14) ◽

pp. 1307-1316

Author(s):

Abdullah K Dolu ◽

Ahmet Korkmaz ◽

Harun Kundi ◽

Umit Guray

Keyword(s):

Essential Hypertension ◽

Shear Rate ◽

Blood Viscosity ◽

Whole Blood ◽

Blood Pressure Monitoring ◽

High Shear Rate ◽

High Shear ◽

Whole Blood Viscosity ◽

Protein Levels ◽

Low Shear

Aim: We aimed to investigate the association between whole blood viscosity (WBV) and nondipping pattern in patients with essential hypertension. Materials & methods: A total of consecutive 530 patients who had been evaluated by ambulatory blood pressure monitoring were included. WBV was estimated by using hematocrit and plasma total protein levels for both WBV in low shear rate (0.5 s-1) and WBV in high shear rate (208 s-1) according to the de Simone’s formula. Results: In the multivariate analysis, low shear rate and high shear rate of WBV were associated independently with nondipping pattern in patients with essential hypertension. Conclusion: As a simple, inexpensive and noninvasive tool, WBV seems to be a significant predictor of nondipping hypertension.

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