12,188 research outputs found
Physical interpretation of the Mullins softening in a carbon-black filled SBR
No full textA 40 phr carbon-black filled styrene butadiene rubber has been submitted to several experiments in order to identify the physical damage responsible for the mechanical softening recorded upon first stretch. Damage in the rubber matrix was determined by swelling. The filler structure alteration was monitored by electrical conductivity measurements. Both damages are shown to be of minor importance compared to the substantial mechanical softening undergone by the material. Degradation at the rubber-filler interface may be recovered by exposing the material at high temperatures in vacuo. The chain mobility in such storage conditions promotes free chain adsorption at the filler surface. The existence of a layer of polymer whose movements are hindered adds to the filler reinforcement and its desorption creates Mullins softening
Charcaterization of the Mullins effect of carbon-black filled rubbers
No full textPublisher version : http://rubberchemtechnol.org/doi/abs/10.5254/1.3592294?journalCode=rcatSeveral carbon-black filled styrene-butadiene rubbers showed different sensibilities to the Mullins softening when submitted to cyclic uniaxial tension. In order to quantify this softening, a damage parameter was introduced. It is defined by using a classic damage approach and can be estimated by using either the strain amplification factor method or the tangent modulus at zero stress. The proposed parameter is used to study the effects of crosslink density and filler amount on the Mullins softening. The latter is shown to remain unaffected by a change of crosslink density and to increase with an increase of filler amount. The damage parameter exhibits mere linear dependences on the maximum Hencky strain applied and on the filler volume fraction. A simple linear expression is given finally to predict the Mullins softening of filled rubbers. The parameter also provides an objective analysis for the Mullins softening that supports comments on a better understanding of this effect.ANR MATETPRO AMUFIS
Constitutive modeling of the anisotropic behavior of Mullins softened filled rubbers
No full textOriginal constitutive modeling is proposed for filled rubber materials in order to capture the anisotropic softened behavior induced by general non-proportional pre-loading histo-ries. The hyperelastic framework is grounded on a thorough analysis of cyclic experimental data. The strain energy density is based on a directional approach. The model leans on the strain amplification factor concept applied over material directions according to the Mul-lins softening evolution. In order to provide a model versatile that applies for a wide range of materials, the proposed framework does not require to postulate the mathematical forms of the elementary directional strain energy density and of the Mullins softening evo-lution rule. A computational procedure is defined to build both functions incrementally from experimental data obtained during cyclic uniaxial tensile tests. Successful compari-sons between the model and the experiments demonstrate the model abilities. Moreover, the model is shown to accurately predict the non-proportional uniaxial stress-stretch responses for uniaxially and biaxially pre-stretched samples. Finally, the model is effi-ciently tested on several materials and proves to provide a quantitative estimate of the anisotropy induced by the Mullins softening for a wide range of filled rubbers
Ex-Slave Narrative - Hannah Mullins
No full textA transcript of an Ex-Slave Narrative interview conducted by Woody Phipps for the Works Progress Administration\u27s Federal Writers\u27 Project in the 1930s with Hannah Mullins. Mullins was born into slavery on the plantation of M. T. Johnson in Johnson City, Texas in the 1850s. In her interview, she describes the buildings at the plantation, the work performed by enslaved people, food, and child care prior to the emancipation of slaves at the end of the Civil War. After he turned five years old, she was a nurse to the Johnson children. After emancipation, she and her family stayed at the Johnson plantation and worked for wages. She describes racial violence perpetrated by the Ku Klux Klan, specifically in the towns of Bowie and Blum, Texas. She also discusses voting rights, including intimidation and tampering. After marrying William Bill Mullins, the couple moved between Arlington, Texas, Fort Worth, Texas, and the all-black community of Boley, Oklahoma.https://mavmatrix.uta.edu/specialcollections_workprojectsadministration/1090/thumbnail.jp
Oral History Interview: John Mullins
No full textThis interview is one of a series conducted concerning rural life in West Virginia. Mr. John Mullins is a native of Webster Springs, West Virginia. This interview is a discussion of his fishing and hunting experiences in Webster County since 1910.https://mds.marshall.edu/oral_history/1068/thumbnail.jp
Dynamic Compartmentalisation of Intracellular Sodium in collecting duct cells
No full textMovie S1.avi - shows localised release of sodium green from a vesicle;
Movie S2.avi - shows decrease in fluorescence of vesicle over time;
Movie S3.mp4 - shows increase in fluorescence of one vesicle with decrease in fluorescence of second vesicle over time.Movie S1.avi - shows localised release of sodium green from a vesicle;
Movie S2.avi - shows decrease in fluorescence of vesicle over time;
Movie S3.mp4 - shows increase in fluorescence of one vesicle with decrease in fluorescence of second vesicle over time
Conversation with Morgan Mullins, Part Two
No full textA conversation with Morgan Mullins, who was denied a marriage license by Rowan County Clerk Kim Davis, for the Kentucky Marriage Equality and Religious Liberty Oral History Project
Oral History Interview: Mr. and Mrs. Eli Mullins
No full textThis interview is one of a series conducted concerning West Virginia coal mining. In this interview, Mr. and Mrs. Mullins discuss briefly a variety of topics, including farming during the Great Depression, mining, the Battle of Blair Mountain, transporting coal, a payroll robbery at Warren Cliff and moonshining. Mr. Mullins also talks of his job as constable in the Huff Creek District, the gathering of ginseng, his work in a mill in Kentucky, blacks in the coal fields, and food. Mother Jones is also mentioned.https://mds.marshall.edu/oral_history/1163/thumbnail.jp
An Exploration in the Power of Community Impact in the Work of Paul Mullins
No full textVideo available at: https://media.dlib.indiana.edu/media_objects/jq086b54hVideo available at: https://youtu.be/hfB0WvKnAto?si=5P16rO12K3OLLyKAProfessor Paul Mullins is a historical archaeologist who studies the intersection of materiality and the color line, focusing on the relationship between racism, consumption, and urban displacement. Dr. Mullins’ research has focused on urban displacement in Indianapolis, examining how a century-old, predominately African-American community was displaced and is now reconstructing its history. His scholarship has included archaeological excavations, documentary research, and oral history in Ransom Place, Flanner House Homes, the present-day IUPUI campus, and postwar African-American suburbs.
During this special event, several of Dr. Mullins’ colleagues share how his work has and continues to impact their lives and academic careers. This presentation also shows how Paul Mullins’ research is an exemplary model of IUPUI faculty members translating research into practice for the betterment of their fields and communities
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