The Action ox Benzoyl Peroxide on Natural Rubber in Solution

1948 ◽  
Vol 21 (1) ◽  
pp. 60-65 ◽  
Author(s):  
Patrice Compagnon ◽  
André Delalande
Keyword(s):  
Maleic Anhydride ◽  
Natural Rubber ◽  
Benzoyl Peroxide ◽  
Systematic Study ◽  
Experimental Results ◽  
Secondary Importance ◽  
The Past ◽  
Unsaturated Compounds ◽  
To Come

Abstract An earlier publication described experiments on the combination of active ethylene compounds, such as maleic anhydride and acrylonitrile, with rubber in solution under the influence of benzoyl peroxide. Control experiments on the action of benzoyl peroxide alone under the same conditions were carried out also, and from the results it was possible to come to certain conclusions. Since then, the reactions of unsaturated compounds with rubber have been investigated more extensively, and further experiments have been carried out on the action of benzoyl peroxide alone. The authors believe that it is of interest to discuss these observations at the present time, for it is not intended to continue with any systematic study of this problem, which actually is only of secondary importance as far as the main purpose of the investigation under way is concerned. Furthermore, it is felt that some of the experimental results may be of importance to other investigators who have studied, in the past few years, the photogelation and oxidation of rubber from the theoretical viewpoint. Finally, in the work already cited, no mention was made of the important part played by oxygen, even when in very low percentages, and this led to an incorrect interpretation of the phenomena, for which it is well to make amends at this time.

The Combined Action of Maleic N-Methylimide and p-Bromobenzoyl Peroxide on Natural Rubber

1948 ◽  
Vol 21 (2) ◽  
pp. 344-346
Author(s):  
André Delalande
Keyword(s):  
Maleic Anhydride ◽  
Acrylic Acid ◽  
Natural Rubber ◽  
Benzoyl Peroxide ◽  
Present Author ◽  
Atmospheric Oxygen ◽  
Bromine Atom ◽  
Unsaturated Compounds ◽  
Combined Action ◽  
In Virtue Of

Abstract It is already known that natural rubber is capable of combining, under certain conditions, with various unsaturated compounds. Bacon and Farmer, for example, have fixed maleic anhydride on rubber in solution in the presence of benzoyl peroxide. This reaction has been applied likewise to acrylic acid, to acrylonitrile and to methacrylonitrile. Bacon and Farmer carried out the reaction with solutions of rubber which were refluxed for 18 hours, without, however, attempting to avoid the extraneous effect of atmospheric oxygen. The present author was, therefore, prompted to carry out the reaction protected from air in sealed tubes into which the solvent was introduced by distillation in a vacuum according to a technique based on that employed by Moureu and Dufraisse in their studies of autoxidation. In an effort to explain the mechanism of the reactions, maleic N-methylimide was chosen as the unsaturated reagent in the reaction and p-bromobenzoyl peroxide as the catalyst. These two compounds, in virtue of the nitrogen atoms and bromine atom in their respective molecules, made it possible to determine by analysis what became of them as a result of the reaction.

Improving Mechanical Properties of Poly-β-Hydroxybutyrate-co-β-Hydroxyvalerate by Blending with Natural Rubber and Epoxidized Natural Rubber

2014 ◽  
Vol 983 ◽  
pp. 179-182 ◽  
Author(s):  
Maneewong Chutamas ◽  
Sunthornvarabhas Jackapon ◽  
Joong Kim Hyun ◽  
Sriroth Klanarong
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Maleic Anhydride ◽  
Impact Strength ◽  
Natural Rubber ◽  
Benzoyl Peroxide ◽  
Storage Modulus ◽  
Epoxidized Natural Rubber ◽  
Mixed Coding ◽  
Elastic Polymer

Poly-β-hydroxybutyrate-co-β-hydroxyvalerate (PHBV) is a bacterial-synthesized biopolymer. Moreover, PHBV is a biodegradable, it is an interesting biopolymer for disposable products. PHBV is difficult to process due to its low toughness, an elastic polymer such as natural rubber is introduced to develop toughness. In this experiment, PHBV mechanical properties were improved by blending with natural rubber (NR) and epoxidized natural rubber (ENR). The NR/PHBV and ENR/PHBV blends with the same ratio of 10/90 (wt/wt) could be extruded, whereas other conditions could not. This ratio was then used throughout this study to examine effect of maleic anhydride (MA) and benzoyl peroxide (BPO) to improve toughness of the blends. Result showed at composition where 1.0 % (wt/wt) MA and 0.05 % (wt/wt) BPO was mixed (coding EPMB2), several aspects of mechanical properties were improved. The blend, EPMB2 revealed the highest impact strength, significantly improved of elongation but drastically decreased of tensile strength. Storage modulus slightly decreased, tangent delta significantly increased when compared with neat PHBV.

Suicidal Behavior in Black South Africans

Crisis ◽  
2003 ◽  
Vol 24 (1) ◽  
pp. 24-28 ◽  
Author(s):  
Lourens Schlebusch ◽  
Naseema B.M. Vawda ◽  
Brenda A. Bosch
Keyword(s):  
South African ◽  
Suicidal Behavior ◽  
Health Care Facilities ◽  
South African Society ◽  
South Africans ◽  
The Past ◽  
The People ◽  
Care Facilities ◽  
Black South Africans ◽  
To Come

Summary: In the past suicidal behavior among Black South Africans has been largely underresearched. Earlier studies among the other main ethnic groups in the country showed suicidal behavior in those groups to be a serious problem. This article briefly reviews some of the more recent research on suicidal behavior in Black South Africans. The results indicate an apparent increase in suicidal behavior in this group. Several explanations are offered for the change in suicidal behavior in the reported clinical populations. This includes past difficulties for all South Africans to access health care facilities in the Apartheid (legal racial separation) era, and present difficulties of post-Apartheid transformation the South African society is undergoing, as the people struggle to come to terms with the deleterious effects of the former South African racial policies, related socio-cultural, socio-economic, and other pressures.

Screen Wonders of the Past: And to Come?

1957 ◽  
Vol 11 (4) ◽  
pp. 381-393
Author(s):  
Kenneth MacGowan
Keyword(s):  
The Past ◽  
To Come

Music and Memory: The Tlatelolco Refrain

2015 ◽  
Vol 2 (1) ◽  
Author(s):  
Josh Kun
Keyword(s):  
State Violence ◽  
First Century ◽  
Student Movements ◽  
Octavio Paz ◽  
Mexican History ◽  
The Past ◽  
Rock Bands ◽  
To Come ◽  
Musical Memory ◽  
A Current

Ever since the 1968 student movements and the events surrounding the Tlatelolco massacre, Mexico City rock bands have openly engaged with the intersection of music and memory. Their songs offer audiences a medium through which to come to terms with the events of the past as a means of praising a broken world, to borrow the poet Adam Zagajewski’s phrase. Contemporary songs such as Saúl Hernández’s “Fuerte” are a twenty-first-century voicing of the ceaseless revolutionary spirit that John Gibler has called “Mexico unconquered,” a current of rebellion and social hunger for justice that runs in the veins of Mexican history. They are the latest additions to what we might think about as “the Mexico unconquered songbook”: musical critiques of impunity and state violence that are rooted in the weaponry of memory, refusing to focus solely on the present and instead making connections with the political past. What Octavio Paz described as a “swash of blood” that swept across “the international subculture of the young” during the events in Tlatelolco Plaza on October 2, 1968, now becomes a refrain of musical memory and political consciousness that extends across eras and generations. That famous phrase of Paz’s is a reminder that these most recent Mexican musical interventions, these most recent formations of a Mexican subculture of the young, maintain a historically tested relationship to blood, death, loss, and violence.

Russian and Soviet historiography of the life and work of Anatoly Fedorovich Koni in the 20th century

2020 ◽  
Vol 2020 (11-1) ◽  
pp. 263-279
Author(s):  
Alexander Kodintsev ◽  
Danil Rybin
Keyword(s):  
20Th Century ◽  
Systematic Study ◽  
The Real ◽  
The Past ◽  
Soviet Historiography

The study analyzes historical researches on the life and work of the outstanding Russian lawyer A. F. Koni. It is noted that several directions in the study of the personality of this figure can be distinguished. It is concluded that systematic study of the legacy of Koni in the context of the era, taking into account the accumulated knowledge, coupled with archival materials will recreate the real face of the remarkable humanist figure of Russia in the past era.

Corporate Reorganization Law and Forces of Change

2020 ◽  
Author(s):  
Sarah Paterson
Keyword(s):  
Financial Crisis ◽  
Conceptual Framework ◽  
Conceptual Frameworks ◽  
Corporate Reorganization ◽  
Process Of Change ◽  
The Past ◽  
To Come ◽  
The Way

This book is concerned with the way in which forces of change, from the fields of finance and non-financial corporates, cause participants in the corporate reorganization process to adapt the ways in which they mobilize corporate reorganization law. It argues that scholars, practitioners, judges, and the legislature must all take care to connect their conceptual frameworks to the specific adaptations which emerge from this process of change. It further argues that this need to connect theoretical and policy concepts with practical adaptations has posed particular challenges when US corporate reorganization law has been under examination in the decade since the financial crisis. At the same time, the book suggests that English scholars, practitioners, judges, and the legislature have been more successful, over the course of the past ten years, in choosing concepts to frame their analysis which are sensitive to the ways in which corporate reorganization law is currently used. Nonetheless, it suggests that new problems may be on the horizon for English corporate reorganization lawyers in adapting their conceptual framework in the decades to come.

scholarly journals A Sense of Presence: Mediating an American Apocalypse

Religions ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 59
Author(s):  
Rachel Wagner
Keyword(s):  
Religious Practice ◽  
Religious Institutions ◽  
The Past ◽  
Sense Of Presence ◽  
The World ◽  
The Future ◽  
To Come

Here I build upon Robert Orsi’s work by arguing that we can see presence—and the longing for it—at work beyond the obvious spaces of religious practice. Presence, I propose, is alive and well in mediated apocalypticism, in the intense imagination of the future that preoccupies those who consume its narratives in film, games, and role plays. Presence is a way of bringing worlds beyond into tangible form, of touching them and letting them touch you. It is, in this sense, that Michael Hoelzl and Graham Ward observe the “re-emergence” of religion with a “new visibility” that is much more than “simple re-emergence of something that has been in decline in the past but is now manifesting itself once more.” I propose that the “new awareness of religion” they posit includes the mediated worlds that enchant and empower us via deeply immersive fandoms. Whereas religious institutions today may be suspicious of presence, it lives on in the thick of media fandoms and their material manifestations, especially those forms that make ultimate promises about the world to come.

3D RECONSTRUCTION OF BREAST CANCER FROM MAMMOGRAMS USING VOLUME RENDERING TECHNIQUES

2015 ◽  
Vol 75 (2) ◽  
Author(s):  
Ho Wei Yong ◽  
Abdullah Bade ◽  
Rajesh Kumar Muniandy
Keyword(s):  
Breast Cancer ◽  
3D Reconstruction ◽  
Computational Cost ◽  
Reconstruction Method ◽  
Cancer Model ◽  
Volume Reconstruction ◽  
The Past ◽  
Breast Cancer Model ◽  
Reconstruction Software ◽  
To Come

Over the past thirty years, a number of researchers have investigated on 3D organ reconstruction from medical images and there are a few 3D reconstruction software available on the market. However, not many researcheshave focused on3D reconstruction of breast cancer’s tumours. Due to the method complexity, most 3D breast cancer’s tumours reconstruction were done based on MRI slices dataeven though mammogram is the current clinical practice for breast cancer screening. Therefore, this research will investigate the process of creating a method that will be able to reconstruct 3D breast cancer’s tumours from mammograms effectively.  Several steps were proposed for this research which includes data acquisition, volume reconstruction, andvolume rendering. The expected output from this research is the 3D breast cancer’s tumours model that is generated from correctly registered mammograms. The main purpose of this research is to come up with a 3D reconstruction method that can produce good breast cancer model from mammograms while using minimal computational cost.

Church Time and Astrological Time in the Waning Middle Ages

2002 ◽  
Vol 37 ◽  
pp. 117-132
Author(s):  
Hilary M. Carey
Keyword(s):  
Middle Ages ◽  
Missed Opportunities ◽  
The Past ◽  
Adam And Eve ◽  
Primary Qualities ◽  
The Future ◽  
Future Events ◽  
Scientific Claims ◽  
To Come

Time, according to medieval theologians and philosophers, was experienced in radically different ways by God and by his creation. Indeed, the obligation to dwell in time, and therefore to have no sure knowledge of what was to come, was seen as one of the primary qualities which marked the post-lapsarian state. When Adam and Eve were cast out of the garden of delights, they entered a world afflicted with the changing of the seasons, in which they were obliged to work and consume themselves with the needs of the present day and the still unknown dangers of the next. Medieval concerns about the use and abuse of time were not merely confined to anxiety about the present, or awareness of seized or missed opportunities in the past. The future was equally worrying, in particular the extent to which this part of time was set aside for God alone, or whether it was permissible to seek to know the future, either through revelation and prophecy, or through science. In the fourteenth and fifteenth centuries, the scientific claims of astrology to provide a means to explain the outcome of past and future events, circumventing God’s distant authority, became more and more insistent. This paper begins by examining one skirmish in this larger battle over the control of the future.

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