Some Observations on Accelerator Practice and Modern Compounding

1934 ◽  
Vol 7 (4) ◽  
pp. 641-647 ◽  
Author(s):  
R. C. Davies
Keyword(s):  
Organic Compounds ◽  
Careful Selection ◽  
Wise Use ◽  
Delayed Action ◽  
The Moment ◽  
Complex Organic ◽  
Selection Of

Abstract In the last twenty-five years a number of complex organic compounds have been developed and patented for the purpose of accelerating the vulcanization of rubber. Really serious bulk usage throughout the trade, however, did not commence until after the war. Research in this field raced ahead of manufacturing progress and brought out accelerators which were so active that they were almost unusable. There are now accelerators which are more than sufficient for the needs of the moment. They cover all ranges of conditions, such as slow, medium slow, semi-fast, semi-ultra, ultra, and super-ultra accelerators. In addition there are modifications for delayed action, quick start, flat peak, high tensile, and superflexing; also accelerators which will cure without heat and others which will cure without added sulfur. In view of the publicity indulged in by the vendors, one might almost feel compelled to change one's accelerators every week. Rationalization is as necessary in the use of accelerators as in the use of fillers. In the wise use of accelerators it is necessary to make a careful selection of only a few which function best in the temperature and process range of any particular manufactures.

Management Development Knowledge Base in the Gulf, Transferability, and Adaptability

2015 ◽  
Vol 4 (1) ◽  
pp. 1-11
Author(s):  
Suhaila E. Alhashemi
Keyword(s):  
Knowledge Base ◽  
National Culture ◽  
Management Development ◽  
Development Programs ◽  
Careful Selection ◽  
Gulf Region ◽  
Fully Integrated ◽  
Know How ◽  
The Moment ◽  
Selection Of

Management development programmes and management in transition is taking its shape in the Gulf Region. The purpose of this paper is to address the key assumptions and knowledge base on which Gulf management development programs were built with special reference to images of managerial professionalism and its major issues bearing on the transferability of managerial know-how. Interviews conducted with managers in Bahrain and Oman revealed using some Western Theories may prove not to be successful when fully integrated with the national culture, and therefore there is a need to adapt. Change and transformation is taking place within the GCC, this necessitates careful selection of strategies and ways to implement management development and transferability. Some organizations have been successful in adaptability and transferability of knowledge, others are undergoing the process at the moment and it will be some time when the effect takes place.

Geometric Education’s Problems Displaying in the “Geometry and Graphics” Journal

2020 ◽  
Vol 8 (3) ◽  
pp. 87-119
Author(s):  
N. Sal'kov
Keyword(s):  
The State ◽  
Pedagogical Issues ◽  
Careful Selection ◽  
The Third ◽  
State Commission ◽  
Set Up ◽  
The Moment ◽  
Second Period ◽  
Selection Of ◽  
Academic Degrees

The “Geometry and Graphics” journal is celebrating its eight-year birthday in 2020. It was set up in 2012. From the moment of its set up until 2016, it was the first period of the journal's life, when pedagogical papers were published three times more than the geometrical ones. In 2016 the journal was put in the list of the State Commission for Academic Degrees and Titles in specialties 05.01.01 and 13.08.00. It was the second period in the journal's life. The number of scientific and pedagogical papers have become approximately equal, which indicates a more careful selection of papers for publication in the journal, as well as introduction the apparatus for independent peer review sorting out papers not falling outside the level of the State Commission for Academic Degrees and Titles’ journal. In 2018 the specialty 13.08.00 was removed, only Engineering Geometry and Computer Graphics remained – the third period in the journal's life began, which was characterized by a sharp fall in the number of pedagogical papers, and little wonder. This trend has been demonstrated in the present paper. As a result, if in the first period pedagogical papers in the journal were equal to 3/4 of papers’ total number, in the third period pedagogical papers number had become only 1/4, that is, had decreased by 3 times. From 2019 (No. 4) Pedagogy has returned to the journal – the fourth period has started. Now in the journal there were two specialties again. When the pedagogical direction was again included in the list, the situation related to publication of pedagogical papers in the journal improved, and on the example of three recently published journal numbers, we can say that they began to publish in the journal technical and pedagogical papers in equal measure. This paper aims to show to the reader the scope of pedagogical issues in papers published in the journal and related to geometric education.

scholarly journals Influence of organic compound functionality on aerosol hygroscopicity: dicarboxylic acids, alkyl-substituents, sugars and amino acids

2017 ◽  
Vol 17 (9) ◽  
pp. 5583-5599 ◽  
Author(s):  
Aleksandra Marsh ◽  
Rachael E. H. Miles ◽  
Grazia Rovelli ◽  
Alexander G. Cowling ◽  
Lucy Nandy ◽  
...  
Keyword(s):  
Molecular Structure ◽  
Amino Acids ◽  
Organic Compounds ◽  
Accurate Determination ◽  
Dicarboxylic Acids ◽  
Original Data ◽  
Set Up ◽  
Complex Organic ◽  
Selection Of

Abstract. Hygroscopicity data for 36 organic compounds, including amino acids, organic acids, alcohols and sugars, are determined using a comparative kinetics electrodynamic balance (CK-EDB). The CK-EDB applies an electric field to trap-charged aqueous droplets in a chamber with controlled temperature and relative humidity (RH). The dual micro dispenser set-up allows for sequential trapping of probe and sample droplets for accurate determination of droplet water activities from 0.45 to > 0.99. Here, we validate and benchmark the CK-EDB for the homologous series of straight-chain dicarboxylic acids (oxalic–pimelic) with measurements in better agreement with Universal Quasichemical Functional Group Activity Coefficients (UNIFAC) predictions than the original data used to parametrise UNIFAC. Furthermore, a series of increasingly complex organic compounds, with subtle changes to molecular structure and branching, are used to rigorously assess the accuracy of predictions by UNIFAC, which does not explicitly account for molecular structure. We show that the changes in hygroscopicity that result from increased branching and chain length are poorly represented by UNIFAC, with UNIFAC under-predicting hygroscopicity. Similarly, amino acid hygroscopicity is under-predicted by UNIFAC predictions, a consequence of the original data used in the parametrisation of the molecular subgroups. New hygroscopicity data are also reported for a selection of alcohols and sugars and they show variable levels of agreement with predictions.

scholarly journals Influence of Organic Compound Functionality on Aerosol Hygroscopicity: Dicarboxylic Acids, Alkyl-Substituents, Sugars and Amino Acids

2016 ◽  
Author(s):  
Aleksandra Marsh ◽  
Rachael E. H. Miles ◽  
Grazia Rovelli ◽  
Alexander G. Cowling ◽  
Lucy Nandy ◽  
...  
Keyword(s):  
Molecular Structure ◽  
Amino Acids ◽  
Organic Compounds ◽  
Accurate Determination ◽  
Dicarboxylic Acids ◽  
Original Data ◽  
Set Up ◽  
Complex Organic ◽  
Selection Of

Abstract. Hygroscopic data for 36 organic compounds including amino acids, organic acids, alcohols and sugars is determined using a Comparative Kinetics Electrodynamic Balance (CK-EDB). The CK-EDB employs an electric field to trap charged aqueous droplets in a temperature and relative humidity (RH) controlled chamber. The dual micro dispenser set up allows for sequential trapping of probe and sample droplets for accurate determination of droplet water activities from 0.45 to > 0.99. Here, we validate and benchmark the CK-EDB for the homologous series of straight chain dicarboxylic acids (oxalic – pimelic) with measurements in better agreement with UNIversal quasichemical Functional group Activity Coefficients (UNIFAC) predictions than the original data used to parametrise UNIFAC. Further, a series of increasingly complex organic compounds, with subtle changes to molecular structure and branching, are used to rigorously assess the accuracy of predictions by UNIFAC, which does not explicitly account for molecular structure. We show that the changes in hygroscopicity that result from increased branching and chain length are poorly represented by UNIFAC, with UNIFAC under-predicting hygroscopicity. Similarly, amino acid hygroscopicity is under-predicted by UNIFAC predictions, a consequence of the original data used in the parametrisation of the molecular subgroups. New hygroscopicity data are also reported for a selection of alcohols and sugars.

Wastewater treatment and nutrient removal in the combined reactor

1998 ◽  
Vol 38 (1) ◽  
pp. 87-95 ◽  
Author(s):  
M. Roš ◽  
J. Vrtovšek
Keyword(s):  
Organic Compounds ◽  
Industrial Wastewater ◽  
Design Procedure ◽  
Order Reaction ◽  
Treated Wastewater ◽  
Nitrification Rate ◽  
Zero Order Reaction ◽  
Aerobic Reactor ◽  
Complex Organic

A combined anaerobic anoxic aerobic reactor for the treatment of the industrial wastewater that contains nitrogen and complex organic compounds as well as its design procedure is presented. The purpose of our experiments was to find a simple methodology that would provide combined reactor design. The reactor is based on the combination of anaerobic, anoxic and aerobic process in one unit only. It was found that the HRT even under 1 hour in the anaerobic zone is long enough for the efficient transformation of complex organic compounds into readily biodegradable COD which is then used in dentrification process. In the N-NO3 concentration range 1.5-50 mg/l the denitrification rate could be expressed as half-order reaction when the CODrb was in excess. N-NO3 removal efficiency is controlled by the recycle flow from the aerobic to the anoxic zone. Nitrification rate can be expressed as first, half or zero-order reaction with respect to effluent N-NH4 concentration. Nitrification rate depends on the dissolved oxygen concentration and hydrodynamic conditions in the reactor. Case study for design of a pilot plant of the combined reactor for treatment of pre-treated pharmaceutical wastewater is shown. Characteristics of pre-treated wastewater were: COD=200 mg/l, BOD5=20 mg/l, N-Kjeldahl=80 mg/l, N-NH4=70 mg/l, N-NOx<1 mg/l, P-PO4=5 mg/l. Legal requirements for treated wastewater were: COD=<100 mg/l, BOD5<5 mg/l, N-NH4=<1 mg/l, N-NOx=<10 mg/l.

Afterword

2020 ◽  
pp. 680-683
Author(s):  
Janice L. Waldron ◽  
Stephanie Horsley ◽  
Kari K. Veblen
Keyword(s):  
Social Media ◽  
Media Use ◽  
Careful Selection ◽  
Social Media Use ◽  
Pedagogical Tools ◽  
The Future ◽  
User Data ◽  
Selection Of ◽  
Data Surface

We all feel the implications of the force of social media—for good and for ill—in our lives and in our professional world. At the time of this writing, Facebook continues with its struggle to “clean up its act” as more revelations surrounding breaches of trust and hacked user data surface in the news and various countries attempt to hold Facebook to account. Despite this, social media use continues to grow exponentially, and the potential for responsible, ethical, and transparent social media to transform the ways in which we interact with and learn from each other increase with it. As we wait to see what the future holds for social media in society, we are reminded once again that it is the careful selection of pedagogical tools such as social media, as well the guided awareness of the challenges and benefits of those tools, that remains constant, even as tools may change, disappear, or fall out of fashion.

Catacomb culture wagons of the Eurasian steppes

Antiquity ◽  
2014 ◽  
Vol 88 (340) ◽  
pp. 378-394 ◽  
Author(s):  
N.I. Shishlina ◽  
D.S. Kovalev ◽  
E.R. Ibragimova
Keyword(s):  
Stable Isotope ◽  
Isotope Analysis ◽  
Burial Mound ◽  
Careful Selection ◽  
Southern Russia ◽  
The Subject ◽  
The Individual ◽  
Wheeled Vehicles ◽  
Selection Of ◽  
Catacomb Culture

The origin and development of wheeled vehicles continues to fascinate today no less than when Stuart Piggott (1974) first wrote about the subject inAntiquity40 years ago. A growing number of examples from the steppes of southern Russia and Ukraine are providing new insights into the design and construction of these complex artefacts. A recent example from the Ulan IV burial mound illustrates the techniques employed and the mastery of materials, with careful selection of the kinds of wood used for the wheels, axles and other elements. Stable isotope analysis of the individual interred in this grave showed that he had travelled widely, emphasising the mobility of steppe populations.

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