Two Stages in the Process of Network Formation in Polymers

1958 ◽  
Vol 31 (3) ◽  
pp. 592-598
Author(s):  
G. M. Bartenev
Keyword(s):  
Molecular Weight ◽  
Network Formation ◽  
Practical Importance ◽  
Critical Number ◽  
Two Stage ◽  
Initial Stage ◽  
Critical Molecular Weight ◽  
Two Stages

Abstract 1. The two-stage nature of network formation in polymers is discussed, and a formula is derived connecting the number of chains in the network with the initial molecular weight of the polymer and the number of crosslinks. It is shown that below a certain critical number of crosslinks a network is not formed. 2. The application of the derived relationships in determination of the number of sulfur atoms in the crosslinks, the critical molecular weight, and the degree of globulization of the rubber, has been studied in the case of rubber vulcanization. 3. The first vulcanization stage is shown to be of considerable practical importance, as it determines the correct technological conditions for the vulcanization of rubber in molding presses, multilayer articles, etc. For this reason, determinations of the vulcanization optimum in rubber technology must be augmented by studies of the initial stage of the process. A method for determining the duration of the first stage of vulcanization is described.

scholarly journals How contractual terms determine fiduciary duties: a two-stage process

2019 ◽  
Vol 70 (2) ◽  
pp. 242-262
Author(s):  
David Gibbs-Kneller ◽  
Derek Whayman
Keyword(s):  
Fiduciary Duty ◽  
Single Factor ◽  
Two Stage ◽  
Fiduciary Duties ◽  
Second Stage ◽  
Stage Process ◽  
Duty Of Loyalty ◽  
Two Stages

The determination of the scope of the fiduciary duty of loyalty, when created by contract, is not a unitary process. It is raised following a multi-factorial enquiry, which considers the nature of the engagement, in a first stage. Here, no single factor is conclusive. It is then, in a separate, second stage, reduced by qualifying contractual terms, which are applied almost strictly logically. This second stage uses the contractual doctrines of interpretation and implication. However, since it is a form of the fiduciary doctrine of authorisation, those contractual doctrines are modified according to fiduciary principles. We argue this follows from the underlying nature of the fiduciary obligation as a way of resolving its internal tensions. While this division has not yet been fully recognised in the cases, the courts have been inching towards it. However, not fully recognising this inevitable division and eliding the two stages has led to defective reasoning and outcomes.

scholarly journals Competence of the cartographic literacy of schoolchildren: essence and methodological foundations of the formation

2019 ◽  
Keyword(s):  
Extracurricular Activities ◽  
Practical Importance ◽  
Educational Process ◽  
Mathematical Basis ◽  
Geographical Education ◽  
Initial Stage ◽  
Theoretical Foundations ◽  
Analysis Of Teaching ◽  
Main Material

The purpose of this article is to characterize the theoretical foundations of the cartographic method in school geography and to highlight the competencies of schoolchildren’s cartographic literacy, the analysis of teaching methods for the formation and development of cartographic literacy of schoolchildren in the process of studying geography. The main material. The main attention is paid to the analysis of the elements of cartographic literacy of pupils, which is formed when studying geography at school. As such elements, not only theoretical knowledge of schoolchildren about the map, but also practical skills to work with the mathematical basis of the map, cartographic image, conventional signs, carry out measurements on the map, and find geographical coordinates are highlighted. Cartographic competencies higher level of pupils are the ability to analyze geographic objects using maps, determine their dynamics, make geographic forecasts, models, apply a map when conducting geographic expertise and design. At the same time, attention is focused on the fact that the competences of cartographic literacy of schoolchildren are initially formed at the initial stage of studying geography at school, and will be claimed and developed throughout the entire geographical education. Cartographic literacy of schoolchildren is based on the use of maps for studying objects and phenomena displayed on them. Its elements are consistently and systematically formed and developed in geography lessons and are of practical importance both in the educational process and in everyday life. Traditionally, in the process of teaching geography, tasks associated with determining the geographical coordinates of objects, measuring distances and orientation on the map are used. In order to increase the creative focus in the study of geography, you can use design tasks based on the use of maps, methods of cartometry and morphometry, modeling of geographical objects, solving tasks of a problem character. Conclusions and further research. These tasks of cartographic subjects significantly expand the competencies of schoolchildren and their horizons, increase the interest in the academic subject and introduce the creative component into the educational process. Further research may be related to the determination of the most effective methodologies for the development and expansion of the cartographic competencies of schoolchildren both in geography and extracurricular activities.

Kant’s Two-Stage Model of Moral Reform

2018 ◽  
Author(s):  
Laura Papish
Keyword(s):  
Final Section ◽  
Moral Progress ◽  
Moral Reform ◽  
Stage Model ◽  
Two Stage ◽  
Second Stage ◽  
Initial Stage ◽  
Metaphysics Of Morals ◽  
Moral Conversion ◽  
Two Stages

This chapter offers an interpretive proposal for Kant’s two-stage model of moral reform in the Religion. Kant explicitly argues that an initial stage of moral conversion must be followed by continual moral progress in the empirical realm, but it is unclear why two stages are needed or how, exactly, they differ from one another. In this chapter, it is argued that one can best understand the first stage if conversion is framed as a kind of commitment, and that one can best understand the second stage if moral progress is conceived more as a cognitive, as opposed to volitional, type of effort. In the final section of this chapter, it is determined that the Metaphysics of Morals presents a compatible account of moral reform. Novel accounts of how to conceptualize moral strength and weakness, and Kant’s emphasis on the importance of empirical conduct, are also offered.

Quantitative Determination of Plasminogen

1970 ◽  
Vol 23 (02) ◽  
pp. 191-201 ◽  
Author(s):  
H. D Bruhn ◽  
L Müller ◽  
F Duckert
Keyword(s):  
Quantitative Determination ◽  
Plasminogen Activator ◽  
Assay System ◽  
Two Stage ◽  
System Activation ◽  
Frozen Plasma

SummaryA modification of the caseinolytic assay for plasminogen is described. This assay system is characterized by the following features :1. Urokinase is used as activator achieving a complete activation of the plasminogen whereas with streptokinase caseinolytically inactive plasminogen-activator complexes are formed.2. All incubation times are reduced to the minimum which is still compatible with accuracy.3. Results are expressed in percent of a standard of ten normal plasmas.4. In this two-stage assay-system (activation of plasminogen to plasmin, digestion of casein by plasmin) both stages proceed simultaneously in the same system, thus the plasmin formed is stabilized “in statu nascendi” by the casein.5. Several conditions (stability of plasminogen in frozen plasma, use of anticoagulants, reproducibility) are defined.

Two-Stage Procedure for the Quantitative Determination of Autoprothrombin III Concentration and Some Applications

1967 ◽  
Vol 18 (01/02) ◽  
pp. 198-210 ◽  
Author(s):  
Ronald S Reno ◽  
Walter H Seegers
Keyword(s):  
Prothrombin Time ◽  
Factor Vii ◽  
Two Stage ◽  
Pronounced Increase ◽  
One Stage ◽  
Assay Procedure ◽  
Bovine Plasma ◽  
The One ◽  
Autoprothrombin C

SummaryA two-stage assay procedure was developed for the determination of the autoprothrombin C titre which can be developed from prothrombin or autoprothrombin III containing solutions. The proenzyme is activated by Russell’s viper venom and the autoprothrombin C activity that appears is measured by its ability to shorten the partial thromboplastin time of bovine plasma.Using the assay, the autoprothrombin C titre was determined in the plasma of several species, as well as the percentage of it remaining in the serum from blood clotted in glass test tubes. Much autoprothrombin III remains in human serum. With sufficient thromboplastin it was completely utilized. Plasma from selected patients with coagulation disorders was assayed and only Stuart plasma was abnormal. In so-called factor VII, IX, and P.T.A. deficiency the autoprothrombin C titre and thrombin titre that could be developed was normal. In one case (prethrombin irregularity) practically no thrombin titre developed but the amount of autoprothrombin C which generated was in the normal range.Dogs were treated with Dicumarol and the autoprothrombin C titre that could be developed from their plasmas decreased until only traces could be detected. This coincided with a lowering of the thrombin titre that could be developed and a prolongation of the one-stage prothrombin time. While the Dicumarol was acting, the dogs were given an infusion of purified bovine prothrombin and the levels of autoprothrombin C, thrombin and one-stage prothrombin time were followed for several hours. The tests became normal immediately after the infusion and then went back to preinfusion levels over a period of 24 hrs.In other dogs the effect of Dicumarol was reversed by giving vitamin K1 intravenously. The effect of the vitamin was noticed as early as 20 min after administration.In response to vitamin K the most pronounced increase was with that portion of the prothrombin molecule which yields thrombin. The proportion of that protein with respect to the precursor of autoprothrombin C increased during the first hour and then started to go down and after 3 hrs was equal to the proportion normally found in plasma.

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