scholarly journals Abrasive resistance of polyetherurethane ureas

2021 ◽  
Vol 2094 (4) ◽  
pp. 042077
Author(s):  
V Yu Senichev ◽  
E V Pogorel’tsev
Keyword(s):  
Experimental Data ◽  
Abrasion Resistance ◽  
Polymer Chains ◽  
Volumetric Wear ◽  
Segmented Polyurethane ◽  
Abrasive Resistance ◽  
Hard Segments ◽  
The Relationship

Abstract The relationship between the structure of the polymer chains and the abrasion resistance of segmented polyurethane ureas based on polyoxytetramethylene oligoether was studied. Experimental data were obtained for systems with the hard segments content above 39%. It was found that the function of the volumetric wear of polyurethane-urea samples on the content of hard segments had an extremum; at high contents of these segments (more than 35%), a further increase in this content lead to a deterioration in the abrasion resistance. The reasons for this effect can be associated with a sharp deterioration in the strength and strain properties of the studied elastomers when additional amounts of diisocyanate are introduced into the system, which can lead to the formation of excessive interchain bonds.

Identifying Physico-Chemical Laws from the Robotically Collected Data

2019 ◽  
Author(s):  
Liwei Cao ◽  
Danilo Russo ◽  
Vassilios S. Vassiliadis ◽  
Alexei Lapkin
Keyword(s):  
Experimental Data ◽  
Numerical Models ◽  
Predictor Variable ◽  
Physical Models ◽  
Training Data ◽  
Mixed Integer ◽  
Physico Chemical ◽  
Data Points ◽  
Future Work ◽  
The Relationship

<p>A mixed-integer nonlinear programming (MINLP) formulation for symbolic regression was proposed to identify physical models from noisy experimental data. The formulation was tested using numerical models and was found to be more efficient than the previous literature example with respect to the number of predictor variables and training data points. The globally optimal search was extended to identify physical models and to cope with noise in the experimental data predictor variable. The methodology was coupled with the collection of experimental data in an automated fashion, and was proven to be successful in identifying the correct physical models describing the relationship between the shear stress and shear rate for both Newtonian and non-Newtonian fluids, and simple kinetic laws of reactions. Future work will focus on addressing the limitations of the formulation presented in this work, by extending it to be able to address larger complex physical models.</p><p><br></p>

Simulation on Extrusion Comminution Model of Roller Press

2010 ◽  
Vol 156-157 ◽  
pp. 1702-1707
Author(s):  
Xiang Wen Cheng ◽  
Jinchao Liu ◽  
Qi Zhi Ding ◽  
Li Ming Song ◽  
Zhan Lin Wang
Keyword(s):  
Experimental Data ◽  
Particle Size ◽  
Field Experiments ◽  
Size Ratio ◽  
Optimum Operating ◽  
Extrusion Force ◽  
Particle Size Ratio ◽  
Small Constant ◽  
Working Parameters ◽  
The Relationship

How to predict the relationship among particle size and among product size, to establish the relationship between the granularity and working parameters in the process of grinding and to determine the optimum operating parameters. With proposing BS squeeze crush model by L. Bass and the idea of roll surface division as the material uneven extrusion force are adopted. Based on field experiments the experimental data is analyzed, the select function and the breakage functions are fitted with MATLAB software, and obtaining their model. The comminution model is determined by the roller division. We obtain the model parameter through the experimental data. Through model analysis shows: the relationship between particle breakage and energy absorption, namely the smaller size of the same power, the lower broken; the breakage diminishes with the decrease of particle size ratio and it will be tending to a small constant when the smaller particle size ratio. The breakage functions rapidly decrease within ratio of between 0.2-0.7. This shows: the energy consumption will rapidly increase when the particle size of less than 0.2 in broken; the selection diminish with the decrease of particle size. Pressure (8-9MPa) should be the most appropriate value.

The Tensile Property of the SPF/Cotton Blended Yarn

2011 ◽  
Vol 321 ◽  
pp. 192-195
Author(s):  
Qing Bin Yang ◽  
Xiao Yang
Keyword(s):  
Experimental Data ◽  
Simple Model ◽  
Tensile Property ◽  
Cotton Fibers ◽  
Blended Yarn ◽  
The Difference ◽  
The Relationship

In order to analysis the relationship between the strength and elongation and the blended ratio of SPF/Cotton blended yarn, the strength and elongation of SPF /cotton blended yarn with different blended ratio were measured and compared with the simple model. The results indicated that For the SPF/cotton blended yarn, the difference between the experimental data and the model value is remarkable because of the high cohesion of the cotton fibers.

scholarly journals Anisotropic Diffusion and the Townsend?Huxley Experiment

1973 ◽  
Vol 26 (4) ◽  
pp. 469 ◽  
Author(s):  
JJ Lowke
Keyword(s):  
Experimental Data ◽  
Electric Field ◽  
Electron Mobility ◽  
Diffusion Coefficients ◽  
Applied Electric Field ◽  
Anisotropic Diffusion ◽  
Diffusion Tubes ◽  
New Formula ◽  
The Relationship ◽  
Diffusion Tube

The relationship between current ratios and electron diffusion coefficients for the Townsend-Huxley experiment is reanalysed with the assumption that diffusion can be represented by two coefficients DT and DL for diffusion transverse and parallel respectively to the applied electric field. When the new formula is used to interpret previous experimental data obtained with a diffusion tube of length 2 cm, the derived values of DT/fl become independent of pressure (fl being the electron mobility). For longer diffusion tubes (~ 6 cm), current ratios are insensitive to DL and the results differ insignificantly from those obtained using the formula previously derived on the assumption that diffusion is isotropic.

Research on Diamond Polishing Process Based on Rough Set

2011 ◽  
Vol 295-297 ◽  
pp. 1856-1859 ◽  
Author(s):  
Yong Tao Ma ◽  
Ye Ma
Keyword(s):  
Experimental Data ◽  
Rough Set ◽  
Engineering Application ◽  
Load Factor ◽  
Hot Metal ◽  
Polishing Process ◽  
Iron Metal ◽  
Diamond Polishing ◽  
The Relationship

Polishing diamond with hot metal method was hard to get experimental data, which was very important to the process of polishing. The relationship between polishing parameters and polishing quantity cannot be easily deduced with the limited experimental data. This paper uses Rough Set method to process the data and some useful conclusions have been drawn. The load factor in polishing process can be ignored in the polishing process. In the case of engineering application, the load merely ensures the contact between diamond and hot iron metal. Other parameters, such as temperature, polishing speed and time, are important factors to the polishing quality.

scholarly journals Restructuring polymers via nanoconfinement and subsequent release

2012 ◽  
Vol 8 ◽  
pp. 1318-1332 ◽  
Author(s):  
Alan E Tonelli
Keyword(s):  
Small Molecule ◽  
Polymer Chains ◽  
Crystalline Lattice ◽  
Host Molecule ◽  
Nanostructured Polymers ◽  
Narrow Channels ◽  
The Past ◽  
The Relationship ◽  
Melting And Crystallization Temperatures ◽  
Melting And Crystallization

During the past several years my students and I have been utilizing certain small-molecule hosts to create nanostructured polymers. This is accomplished by first forming noncovalently bonded inclusion complexes (ICs) between these small-molecule hosts and guest polymers, followed by the careful removal of the host crystalline lattice to obtain a coalesced bulk polymer. We have repeatedly observed that such coalesced polymer samples behave distinctly from those produced from their solutions or melts. Coalesced amorphous homopolymers exhibit higher glass-transition temperatures, while crystallizable homopolymers coalesced from their ICs display higher melting and crystallization temperatures, and sometimes different crystalline polymorphs. When ICs are formed with block copolymers or with two or more different homopolymers, the resulting coalesced samples can exhibit intimate mixing between the copolymer blocks, or between entire homopolymer chains. Each of the distinct behaviors observed for polymers coalesced from their ICs is a consequence of the structural organization of the polymer–host-ICs. Polymer chains in host-IC crystals are confined to occupy narrow channels (diameter ~0.5–1.0 nm) formed by the small-molecule hosts around the included guest polymers during IC crystallization. This results in the separation and high extension of the included guest polymer chains, which leads, following the careful removal of the host molecule lattice, to unique behaviors for the bulk coalesced polymer samples. Apparently, substantial degrees of the extended and unentangled natures of the IC-included chains are retained upon coalescence. In this review we summarize the behaviors and uses of coalesced polymers, and attempt to draw conclusions on the relationship between their behavior and the organization/structures/conformations of the constituent polymer chains achieved upon coalescence from their ICs.

Calculus of the Relationship of the Cutting Moment at Drilling of the Stainless Steel X15CrNiSi20-12

2015 ◽  
Vol 760 ◽  
pp. 469-474 ◽  
Author(s):  
Aurelian Vlase ◽  
Ovidiu Blăjină ◽  
Marius Iacob
Keyword(s):  
Experimental Data ◽  
Stainless Steel ◽  
Mathematical Software ◽  
Technical Literature ◽  
Technical Research ◽  
Analytic Relationship ◽  
Subsequent Processing ◽  
Manufacturing Activity ◽  
Relationship Of ◽  
The Relationship

This paper studies the cutting moment at drilling of the stainless steel X15CrNiSi20-12. The structure of the cutting moment relation was modified with respect to the relation available in the technical literature for common steels. The tool speed was included in the calculus relation. The experimental data and their subsequent processing represent the original contributions of the authors to the estimation of polytropic exponents and to the assessment in terms of structure of the calculus relation of the cutting moment. The paper also contains graphs for the variation of the cutting moment with parameters of the cutting technology. The graphs are drawn based on the analytic relationship of the cutting moment, obtained in the paper, using the mathematical softwareMaple. The results presented in this study can be taken into consideration in the educational studies and in the theoretical technical research. Also, they can be readily implemented in the manufacturing activity. Our further studies aim these problems for another steels classes.

Enhancing Polynuclear Aromatic Uptake into Bulk Solution with Amphiphilic Colloidal Aggregates

1992 ◽  
Vol 26 (9-11) ◽  
pp. 2341-2344 ◽  
Author(s):  
D. A. Edwards ◽  
Z. Liu ◽  
R. G. Luthy
Keyword(s):  
Experimental Data ◽  
Partition Coefficients ◽  
Solution Concentration ◽  
Aqueous System ◽  
Bulk Solution ◽  
Similar System ◽  
Colloidal Aggregates ◽  
Total Fraction ◽  
The Relationship ◽  
Amphiphilic Aggregates

Aggregated amphiphiles in an aqueous or solid/aqueous system can substantially enhance the uptake of polynuclear aromatic (PNA)compound into a bulk solution. The extent of PNA compound incorporated in an amphiphilic aggregate solution in the absence of solids is linearly dependent on the bulk solution concentration of the aggregated form of the amphiphile. In a system in which solids are in contact with a solution, however, the relationship is nonlinear as a result of the adherence of both amphiphile and PNA compound to the solids. The formation of amphiphile aggregates in the bulk solution of a system containing solids occurs only after a much greater amount of amphiphile has been added to the system than would be required for a similar system containing only solution. The partitioning of PNA compound between the solid, the colloidal amphiphilic aggregates in bulk solution, and the rest of the bulk solution can be characterized with two different partition coefficients and a number of other parameters, all of which are obtainable from independent experiments. The total fraction of PNA compound incorporated into bulk solution can be estimated with a mathematical model. Model results for the uptake of pyrene into a C8PE9.5 aggregate solution are shown plotted with experimental data. The effect of amphiphile aggregates on PNA compound transport in porous media may in some cases be substantial.

scholarly journals Consistency and overfitting of multi-omics methods on experimental data

2019 ◽  
Vol 21 (4) ◽  
pp. 1277-1284 ◽  
Author(s):  
Sean D McCabe ◽  
Dan-Yu Lin ◽  
Michael I Love
Keyword(s):  
Experimental Data ◽  
Factor Analysis ◽  
Canonical Correlation ◽  
Cross Validation ◽  
Small Sample Size ◽  
R Package ◽  
Small Sample ◽  
Ready Availability ◽  
Variation Explained ◽  
The Relationship

Abstract Knowledge on the relationship between different biological modalities (RNA, chromatin, etc.) can help further our understanding of the processes through which biological components interact. The ready availability of multi-omics datasets has led to the development of numerous methods for identifying sources of common variation across biological modalities. However, evaluation of the performance of these methods, in terms of consistency, has been difficult because most methods are unsupervised. We present a comparison of sparse multiple canonical correlation analysis (Sparse mCCA), angle-based joint and individual variation explained (AJIVE) and multi-omics factor analysis (MOFA) using a cross-validation approach to assess overfitting and consistency. Both large and small-sample datasets were used to evaluate performance, and a permuted null dataset was used to identify overfitting through the application of our framework and approach. In the large-sample setting, we found that all methods demonstrated consistency and lack of overfitting; however, in the small-sample size setting, AJIVE provided the most stable results. We provide an R package so that our framework and approach can be applied to evaluate other methods and datasets.

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