People Make the Difference

1990 ◽  
Vol 63 (5) ◽  
pp. 81-95
Author(s):  
Benjamin Kastein
Keyword(s):  
Technical Information ◽  
American Chemical Society ◽  
Chemical Society ◽  
Early Years ◽  
Neutral Position ◽  
National Bureau ◽  
Chief Chemist ◽  
The Subject ◽  
The Difference

Abstract The Las Vegas meeting of the Rubber Division, ACS, provided attendees the opportunity to hear the interview of Mr. Arnold H. Smith, by Mr. Herbert A. Endres, recorded April 7, 1966. Mr. Smith, as Secretary-Treasurer of the Division from 1919 to 1928, and as Chairman in 1929, was the person most responsible for laying the foundation which supported the growth of the Division to its present status. The India Rubber Section was sanctioned by the American Chemical Society on December 30, 1909. The 28 chemists from the rubber industry who were the organizing members, had the objective of meeting together to solve mutual problems. The major problem for everyone in 1909 was the variable quality of the 36 varieties of wild rubber from the jungles of Central and South America and Africa. Para rubber from the Hevea Brasiliensis tree was considered to be the best type available, but there were at least 13 variations, identified by source of the Para rubber. Charles C. Goodrich, as first chairman of the India Rubber Section, moved immediately to resolve the problem and appointed a committee, chaired by Dr. Charles Knight of Buchtel College, to develop standard methods of testing and evaluation. The committee diligently addressed the subject and reported to the Section at each meeting for 10 years, but progress was slow. Members attending had been instructed by their superiors, “Listen—but don't talk!” Not a very satisfactory format for conducting a meeting. Several key individuals helping to organize the India Rubber Section were W. C. Geer, Chief Chemist at the B. F. Goodrich Co. and George Oenslager, of the Diamond Rubber Co. Geer invented the air oven used to accelerate heat aging of rubber samples, and Oenslager is famous for discovering the effect on vulcanization of organic accelerators in 1906 and for the use of carbon blacks in treads in 1911. Although the sharing of technical information was tantalizing slow during the early years, the American Chemical Society, at their meeting in Buffalo, April 7, 1919, approved the formation of the Division of Rubber Chemistry. John B. Tuttle, first chairman of the Division in 1919, with Arnold H. Smith as secretary-treasurer, determined to bring to the members technical information less restricted in content, and from their neutral position of employment at the National Bureau of Standards, thought results could be obtained.

Some Problems Involved in the Grading and Testing of Natural Rubber. A Progress Report

1950 ◽  
Vol 23 (1) ◽  
pp. 107-116 ◽  
Author(s):  
W. P. Fletcher
Keyword(s):  
Natural Rubber ◽  
Maximum Modulus ◽  
American Chemical Society ◽  
Chemical Society ◽  
Standard Test ◽  
Great Sensitivity ◽  
National Bureau ◽  
Testing Procedures ◽  
Cure Time

Abstract In the establishment of grading and testing procedures for natural rubber based on the properties of vulcanizates, four main questions arise. First it is necessary to decide on the property to be measured, and reasons are given for the choice of elongation at a fixed load for the purpose, elongations being below 250 per cent. Secondly the method of test had to be decided, and a simple version of the National Bureau of Standards' strain tester has been developed and is in use. Thirdly a standard test mix, into which the raw rubber samples are compounded, must be selected; the well known No. 1 compound of the Crude Rubber Committee of the American Chemical Society has been found to be defective because of its great sensitivity to moisture, whereas a mixed mercaptobenzothiazole-diphenylguanidine stock and a stock accelerated with N-cyclohexyl-2-benzothiazole sulfenamide appear suitable. Finally the interpretation of results is discussed. The use of a single cure for classification of rubbers is felt to be inadequate, and to determine both the maximum modulus of which the rubber is capable in the compound and also the cure time to obtain this condition, it is proposed to define the property with tolerance limits at three cures. Incidental problems arising include mixing error, and some investigation of this is described.

Differences of Pareto principle performance in e-resource download distribution

2016 ◽  
Vol 34 (5) ◽  
pp. 846-855 ◽  
Author(s):  
Qiandong Zhu ◽  
Huimin Xiang
Keyword(s):  
American Chemical Society ◽  
Chemical Society ◽  
Time Change ◽  
Pareto Principle ◽  
American Institute ◽  
Digital Resources ◽  
Content Type ◽  
Business Source Premier ◽  
Single Discipline ◽  
The Difference

Purpose The purpose of this paper is to explore whether the databases from a certain library are Pareto-compliant or not? If so, to what extent is the Pareto principle performance evident among these databases? The other purpose is to determine the differences in Pareto principle performance according to time change and database type. Design/methodology/approach Data on full-text downloads from six e-resources – Elsevier ScienceDirect (SD), Wiley Blackwell, Springer Journal, EBSCO Business Source Premier (BSP), American Chemical Society and American Institute of Physics (AIP) – for the period 2007-2013 were analysed; 42 samples were collected from these databases. The proportion of frequently downloaded journals from databases was selected as an indicator to determine differences in Pareto principle performance according to time change. The difference between the proportion of frequently downloaded journals and the classic proportion of 20 per cent was used as indicator to determine difference in Pareto principle performance related to database type. Findings There are 33 samples (78.57 per cent) which exhibited the Pareto principle. Four databases – Elsevier SD, Wiley Blackwell, EBSCO BSP and AIP – constantly exhibited the Pareto principle. The differences were not significant according to time change. The two multi-discipline databases – Elsevier SD and Wiley Blackwell – fluctuated more moderately than the two single-discipline databases – EBSCO BSP and AIP. Multi-discipline and single-discipline databases showed some differences in Pareto principle performance; however, these differences were not remarkable. Originality/value The Pareto principle confirmed that there were frequent and infrequent downloads of e-journals from e-journal databases. It was of great importance to analyse these to improve digital resources acquisition and user service.

Boundary Conditions

2018 ◽  
Author(s):  
Sauro Succi
Keyword(s):  
Boundary Conditions ◽  
Crucial Role ◽  
Fluid Dynamic ◽  
Fluid Flows ◽  
Dynamic Simulations ◽  
The Past ◽  
Surrounding Environment ◽  
The Subject ◽  
The Difference

The actual dynamics of fluid flows is highly dependent on the surrounding environment, whose influence is mathematically described through the prescription of suitable boundary conditions. Boundary conditions play a crucial role, as they select solutions which are compatible with external constraints. Accounting for these constraints may be comparatively simple for idealized geometries but for general ones it represents a delicate (and sometimes nerve-probing!) task. In fact, the treatment of the boundary conditions often makes the difference in the quality of fluid dynamic simulations. This chapter illustrates the most common ways to impose boundary conditions to LB flows. The subject is very technical and has grown considerably for the past decade, which means that this chapter can only serve as a guiding introduction to the vast and still growing original literature.

Practical Method for Obtaining Dry Air for Humidity Control in a Rubber Laboratory

1929 ◽  
Vol 2 (2) ◽  
pp. 318-322
Author(s):  
F. S. Conover
Keyword(s):  
Relative Humidity ◽  
Laboratory Testing ◽  
American Chemical Society ◽  
Practical Method ◽  
Chemical Society ◽  
Testing Laboratories ◽  
Physical Testing ◽  
Cent Relative Humidity ◽  
The Subject ◽  
Short Time

Abstract THE effect of relative humidity on rubber-testing has been the subject of much recent investigation. String-field and Conover and Depew have published papers on this subject. The last-named authors recommended that the rubber be stored in dry cabinets before milling, between milling and vulcanization, and between vulcanization and testing, at a temperature of 75° ±5° F. A short time later the Physical Testing Committee of the Rubber Division of the American Chemical Society recommended that all laboratory testing be carried out at 45 per cent relative humidity and 82° ±5°F. While both methods have undoubted merit, it was believed that for physical testing laboratories, particularly such as this one, zero humidity was both more conducive to reliable results and easier to maintain. Accordingly, equipment was installed for maintaining zero humidity and its performance has been consistently good. Since several of the larger rubber laboratories have shown interest in the equipment, it has been decided to present this description of the installation and its operation.

scholarly journals Polydimethylsiloxane mechanical properties: A systematic review

2021 ◽  
Vol 8 (6) ◽  
pp. 952-973
Author(s):  
Inês Teixeira ◽  
◽  
Inês Castro ◽  
Violeta Carvalho ◽  
Cristina Rodrigues ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Chemical Properties ◽  
American Chemical Society ◽  
Relevant Information ◽  
Chemical Society ◽  
Thermal Coefficient ◽  
Lab On Chip ◽  
Advantages And Disadvantages ◽  
On Chip

<abstract> <p>Polydimethylsiloxane (PDMS) has been a promising material for microfluidic, particularly in lab-on-chip. Due to the panoply of good physical, mechanical and chemical properties, namely, viscosity, modulus of elasticity, colour, thermal conductivity, thermal coefficient of expansion, its application has been increasingly requested in quite different areas. Despite such characteristics, there are also some drawbacks associated, and to overcome them, several strategies have been developed to modify PDMS. Given the great variety of relevant conducted research in this field, the present work aims to gather the most relevant information, the advantages and disadvantages of some of the techniques used, and also identify potential gaps and challenges in it. To this end, a systematic literature review was conducted by collecting data from four different databases, Science Direct, American Chemical Society, Scopus, and Springer. Two authors independently screened the references, extracted the key information, and assessed the quality of the included studies. After the analysis of the collected data, 25 studies were selected that addressed the various mechanical properties of PDMS and how to modify them in order to suit a particular application.</p> </abstract>

scholarly journals METHODS OF FORMING MOTIVATION OF YOUNGER SCHOOLCHILDREN IN THE COURSE OF EDUCATION

2020 ◽  
Vol 65 (1) ◽  
pp. 394-400
Author(s):  
G.B. Rakisheva ◽  
◽  
M. Maty ◽  
M.A. Kenenbaeva ◽  
◽  
...  
Keyword(s):  
Elementary School Students ◽  
Learning Process ◽  
Teaching Experience ◽  
Quality Of Education ◽  
School Students ◽  
Research Problems ◽  
The Subject ◽  
The Difference ◽  
Class Teacher

The article describes how the motivation of elementary school students went through teaching experience and demonstrated good results. The difference between an external motive and an internal motive is described. In the process of motivation, types of rewards and requirements for pedagogical incentives are summarized. Using these approaches, the student’s influence and change is recorded. The goals, new approaches and the results of the first days of research and post-research problems of motivation in the learning process are shown. Thanks to this study, using the motivation of each student, one of the ways in which the student mastered the subject and determined the way to achieve the goal of the lesson was investigated. In improving the quality of education for a class teacher, it also played a role for the subject teacher.Defined orientation on students. It was shown that students participated in competitions in the direction and won prizes. Positive changes were observed after the motivation had been formed for both the teacher and the student.

scholarly journals ACS Publications — Ensuring XML Quality

2012 ◽  
Author(s):  
Tamara Stoker ◽  
Keith Rose
Keyword(s):  
American Chemical Society ◽  
Chemical Society ◽  
Publication Time ◽  
High Level ◽  
Publication Workflow ◽  
Very High

The benefits of using XML in publishing are widely known but those benefits are more difficult to attain if the quality of the XML produced by the process is not consistently at a very high level. This case study outlines the steps that the American Chemical Society (“ACS”) has taken both in-house and in collaboration with the vendor to which we have outsourced portions of our publication workflow. In addition to producing predictable XML, these efforts have also improved our publication time.

Secondary School Students’ Opinions on the Selected Problems at PE Lessons

2014 ◽  
Vol 23 (1-2) ◽  
pp. 39-58
Author(s):  
Branislav Antala ◽  
Jaromír Šimonek ◽  
Natália Czaková
Keyword(s):  
Physical Education ◽  
Young People ◽  
Secondary School ◽  
Secondary Schools ◽  
Secondary School Students ◽  
Research Paper ◽  
School Students ◽  
The Subject ◽  
The Difference

Abstract Research paper deals with the opinions of students of secondary schools on physical education lessons at school. The aim was to find out various aspects of education such as popularity, demandingness, importance of the subject, feelings and emotions during PE lessons, and sport preferences of young people. The results have shown that the opinions of students on popularity, significance, talent, motivation and effort exerted during PE lessons were more positive than negative. Boys stated that they consider the subject not difficult, popular, and they show effort at lessons. Girls stated that the subject is not demanding, popular, but in a smaller degree than boys. Girls marked the subject as less importantn they show less talent for it and are less motivated for it than boys. As to boys, PE & Sport lessons evoke always or mostly emotions, while the answers of girls oscillated between mostly emotional, sometimes emotional or sometimes unemotional. Difference between the answers of boys and girls was statistically significant on the level of p<0,05. The answers of boys and girls to the question concerning cancellation of a PE lesson were oscillating between the values 2 and 3 (I am often happy; my opinion is indifferent), despite the fact that they stated in the questionnaire that they mostly feel well at PE lessons. The difference between both genders is statistically significant on the level of p<0,05. The answers of boys and girls to the question concerning satisfaction with the content of PE lessons oscillated between the values 2 and 3 (satisfied; partially satisfied, partially not satisfied). Generally we can state that the answers of students were more positive than negative. The difference between the answers of both genders is not statistically significant on the level of 0,05 (p=0,07). The answers to the question concerning the quality of PE lessons oscillated between the values 2-3 (mostly of good quality, changing quality). Boys presented a little more positive answers than girls, however, the difference between both genders is not statistically significant on the level of 0,05 (p=0,411).

Some Neglected Problems in the Rheology of High Polymers

1962 ◽  
Vol 35 (5) ◽  
pp. 27-40 ◽  
Author(s):  
Melvin Mooney
Keyword(s):  
Flow Behavior ◽  
American Chemical Society ◽  
Chemical Society ◽  
The United States ◽  
Theoretical Argument ◽  
Full Time ◽  
Flow Properties ◽  
The Past ◽  
Third Person ◽  
The Subject

Abstract In accordance with custom, I have been asked, as a Goodyear Medalist, to address the Division of Rubber Chemistry of the American Chemical Society on the subject of my past work in the science and technology of elastomers. Hoping that I have correctly understood your desires, I shall now give you an informal, anecdotal story of some of this work. Going beyond this story of the past I shall also sketch, as I now see them, certain related unsolved problems, some of which have been rather neglected. While keeping in mind that detailed mathematics and theoretical argument would be inappropriate and even unwelcome on this occasion, I shall endeavor, with very little mathematics, to stimulate some of you to initiate programs of research on some of these problems, if you have not already done so. First let me tell you how, without realizing it, I became a rheologist. When I was employed by the United States Rubber Company in the fall of 1928, my first assignment was to study rubber plasticity, or the flow properties of crude rubbers and raw compounded stocks. When I was told of this problem in a conference with my group leader, Dr. Roscoe H. Gerke, there was a third person present, Dr. Ernest J. Joss, a physical chemist. Dr. Joss had only shortly before been given the same assignment; but with my appearance in the group, he was permitted to drop this work and give his full time to more congenial tasks. At the conference he turned over to me some talced strips of pale crepe which had been cut from a batch on a laboratory mill after various milling times. I knew nothing about rubber at that time; and if I had been asked to guess what these samples were, I could only have replied that they looked like fillets of sole sprinkled with flour and ready for the frying pan. The rheologieal testing devices for raw rubber that were available at that time were of two forms, the compression plastometer and the extrusion plastometer. I quickly decided that neither of these was suitable for the purpose, which, as I conceived it, was to measure the flow behavior of raw rubbers or stocks in their working condition as exhibited on a mill or calender or in a tuber.

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