Ultrasonic Devulcanization Reactors for Recycling of GRT: Comparative Study

2001 ◽  
Vol 74 (2) ◽  
pp. 317-330 ◽  
Author(s):  
Jushik Yun ◽  
Jeonq Seok Oh ◽  
A. I. Isayev
Keyword(s):  
Power Consumption ◽  
Comparative Study ◽  
Physical Properties ◽  
Crosslink Density ◽  
Positive Influence ◽  
Reactor Power ◽  
Ground Tire Rubber ◽  
Gel Fraction ◽  
The Comparative Study ◽  
Barrel Reactor

Abstract The present paper describes the comparative study of a continuous ultrasonic devulcanization of ground tire rubber (GRT) using two reactors. The devulcanization zone in the first reactor (coaxial reactor) is located at the exit from an extruder without imposition of additional shearing. In the second reactor (barrel reactor), the devulcanization zone is located in barrel where additional shearing takes place due to screw rotation. Gel fraction, crosslink density, cure behavior and physical properties of GRT obtained in these two reactors were measured. Also, the distribution of gel fraction and crosslink density at various locations in the devulcanization zone of the barrel reactor were determined. Gel fraction and crosslink density show that GRT in both reactors is partially devulcanized. A unique correlation between gel fraction and crosslink density obtained in both reactors indicated that additional shearing had a positive influence on improving the efficiency of devulcanization. Under the optimal devulcanization condition, the physical properties of revulcanized GRT and the output are higher in the barrel reactor. Power consumption density in the barrel reactor is found to be significantly higher.

Continuous Ultrasonic Devulcanization: Comparison of Carbon Black Filled Synthetic Isoprene and Natural Rubbers

2008 ◽  
Vol 81 (1) ◽  
pp. 19-46 ◽  
Author(s):  
Ximei Sun ◽  
A. I. Isayev
Keyword(s):  
Carbon Black ◽  
Power Consumption ◽  
Crosslink Density ◽  
Chain Structure ◽  
Ultrasonic Power ◽  
Gel Fraction ◽  
Fraction Versus ◽  
The Difference ◽  
Lower Torque ◽  
Kinetics Of

Abstract Continuous ultrasonic devulcanization of carbon black (CB) filled isoprene rubber (IR) was carried out. Similar to unfilled IR, power consumption during the devulcanization of the filled IR increased with the increase of ultrasonic amplitude indicating a greater extent of devulcanization. This was in contrast with the devulcanization of CB filled natural rubber (NR) where power consumption showed a maximum at an intermediate amplitude suggesting a lesser extent of devulcanization at higher amplitude. Such a behavior evidently resulted from the difference in the amount of stereoregular structures in the IR and NR rubbers. Gel fraction and crosslink density of the virgin vulcanizates, devulcanizates and revulcanizates were characterized. Kinetics of revulcanization, rheological properties of the devulcanizates and mechanical properties of revulcanizates were compared with those of virgin uncured IR and their vulcanizates. The effect of processing oil on the IR vulcanization, devulcanization and revulcanization was examined indicating a slight delay of the vulcanization and lower torque without affecting the degree of reversion. The addition of oil caused more devulcanization as indicated by an increase in the ultrasonic power consumption and a reduction of the gel fraction and crosslink density of devulcanized rubbers. The revulcanization of the IR occurred without the induction period, regardless of the presence of CB and processing oil. The retarder introduced in the recipe was effective in improving the scorch safety and minimizing the reversion in revulcanization. The experimental data on normalized gel fraction versus crosslink density of filled IR and NR at low CB loadings was found to fall into the master curve, which is probably determined by the main chain structure of both rubbers consisting of cis-1,4 isoprene. At high CB loadings, some differences were observed. The simulation results predicted such a behavior.

The Comparative Study of Y123 and Y13-20-33 Superconductors Synthesized by Melt Process

2016 ◽  
Vol 675-676 ◽  
pp. 303-306
Author(s):  
Sutee Chantrapakajee ◽  
Piyamas Chainok ◽  
Supphadate Sujinnapram ◽  
Thanarat Khuntak ◽  
Tunyanop Nilkamjon ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Heat Treatment ◽  
Critical Temperature ◽  
Grain Boundary ◽  
Comparative Study ◽  
Physical Properties ◽  
Flat Surface ◽  
Orthorhombic Crystal ◽  
Orthorhombic Crystal Structure ◽  
The Comparative Study

Abstract. In this research, we synthesized and investigate the physical properties of YBaCuO superconductor; Y123 and Y13-20-30. The melt process was used for heat treatment of our samples. We found that the critical temperature onset of Y13-20-33 and Y123 were at 90 K and 94 K, respectively. The morphology of Y123 superconductor has flat surface and more clear grain boundary than Y13-20-33 superconductor. However, more melted of grain boundary were found on Y13-20-33. Both samples were the orthorhombic crystal structure that c/a ratio of Y13-20-33 was higher than of Y123 superconductor.

Pandhawa Gubah sebagai Representasi Interaksi Metafisik Manusia Jawa dan Perbandingannya dengan Cheritera Pandawa Lima

Manuskripta ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 67
Author(s):  
Novarina Novarina
Keyword(s):  
Comparative Study ◽  
Literary Theory ◽  
Research Method ◽  
Descriptive Analysis ◽  
Literary Study ◽  
Analysis Method ◽  
Research Objects ◽  
Similarities And Differences ◽  
The Difference ◽  
The Comparative Study

Abstract: This research is a comparative literary study that uses Malay and Javanese versions of Mahabarata text sources. The research objects used were the text edition of Pandhawa Gubah (PG) by Sudibjo Z. Hadisutjipto and the text of Cheritera Pandawa Lima (CPL) by Khalid Hussain. The research method used is descriptive-analysis method. In the comparative study used a comparative literary theory proposed by Endraswara (2011). The results of the text comparison reveal the similarities and differences in the image of Bima figures in the Javanese and Malay versions. The equation as a whole is that both texts contain the same heroic storyline and heroic character, Bima. In addition, Indian influence is still evident in the two texts seen from the nuances of Hinduism that exist in both texts. While the difference is seen in the events that accompany Bima's struggle in achieving his victory. Based on these similarities and differences, it can be seen that the authors attempt to represent the concept of metaphysical interactions vertically and horizontally expressed through PG text. --- Abstrak: Penelitian ini adalah satu kajian sastra bandingan yang menggunakan sumber teks Mahabarata versi Melayu dan Jawa. Objek penelitian yang digunakan adalah edisi teks Pandhawa Gubah (PG) karya Sudibjo Z. Hadisutjipto dan teks Cheritera Pandawa Lima (CPL) karya Khalid Hussain. Metode penelitian yang digunakan adalah metode deskriptif-analisis. Dalam telaah perbandingan digunakan teori sastra bandingan yang dikemukakan Endraswara (2011). Hasil perbandingan teks mengungkapkan adanya persamaan dan perbedaan citra tokoh Bima dalam versi Jawa maupun versi Melayu. Persamaan secara keseluruhan adalah kedua teks tersebut mengandung alur cerita kepahlawanan dan tokoh pahlawan yang sama yaitu Bima. Selain itu, pengaruh India masih tampak dalam kedua teks tersebut dilihat dari nuansa Hinduisme yang ada dalam kedua teks. Sementara perbedaannya tampak pada peristiwa-peristiwa yang menyertai perjuangan Bima dalam mencapai kemenangannya. Berdasarkan persamaan dan perbedaan tersebut tampak adanya upaya penulis untuk merepresentasikan konsep interaksi metafisik secara vertikal dan horizontal yang diungkapkan melalui teks PG.

Auslandswissenschaft und kontrastive Kulturkomparatistik

2008 ◽  
Vol 2008 (1) ◽  
pp. 37-44
Author(s):  
Teruaki Takahashi
Keyword(s):  
Comparative Study ◽  
Intercultural Communication ◽  
Cultural Comparison ◽  
Intercultural Understanding ◽  
The Comparative Study

In the context of the controversies surrounding »globalisation« and In the context of the controversies surrounding »globalisation« and »multiculturality« the comparative study of cultures has the task of aiding intercultural communication and of contributing to the success of intercultural understanding. The model of contrastive cultural comparison discussed here is claimed to have applacibility to every possible study of other countries (»Auslandswissenschaft«) and to be able to provide the Geisteswissenschaften with an intercultural orientation.

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