Sebelas Maret University

About: Sebelas Maret University is a education organization based out in Surakarta, Indonesia. It is known for research contribution in the topics: Population & Public health. The organization has 10901 authors who have published 10832 publications receiving 33057 citations. The organization is also known as: Universitas Negeri Surakarta & Universitas Sebelas Maret.

Enhancement of Particle Alignment Using Silicone Oil Plasticizer and Its Effects on the Field-Dependent Properties of Magnetorheological Elastomers

Abstract: The existing mold concept of fabricating magnetorheological elastomer (MRE) tends to encounter several flux issues due to magnetic flux losses inside the chamber. Therefore, this paper presents a new approach for enhancing particle alignment through MRE fabrication as a means to provide better rheological properties. A closed-loop mold, which is essentially a fully guided magnetic field inside the chamber, was designed in order to strengthen the magnetic flux during the curing process with the help of silicone oil (SO) plasticizers. The oil serves the purpose of softening the matrix. Scanning electron microscopy (SEM) was used to observe the surface morphology of the fabricated MRE samples. The field-dependent dynamic properties of the MREs were measured several ways using a rheometer, namely, strain sweep, frequency sweep, and magnetic field sweep. The analysis implied that the effectiveness of the MRE was associated with the use of the SO, and the closed-loop mold helped enhance the absolute modulus up to 0.8 MPa. The relative magnetorheological (MR) effects exhibited high values up to 646%. The high modulus properties offered by the MRE with SO are believed to be potentially useful in industry applications, particularly as vibration absorbers, which require a high range of stiffness.

Pendidikan Kewirausahaan di Perguruan Tinggi: Pentingkah untuk Semua Profesi?

Abstract: Abstrak: Pendidikan Kewirausahaan di Perguruan Tinggi: Pentingkah untuk Semua Profesi? Pendidikan kewirausahaan sudah dikembangkan hampir di semua perguruan tinggi di Indonesia dengan proses yang sangat bervariasi yang bertujuan untuk menciptakan wirausaha. Wirausaha adalah seseorang yang dengan kreativitasnya menciptakan sesuatu yang memiliki values, baik dalam bentuk tangible maupun intangible. Proses tersebut dapat dilakukan di dalam perusahaan yang diciptakan sendiri maupun di dalam organisasi di mana seseorang bekerja. Tujuan artikel ini adalah mengembangkan pemahaman tentang pentingnya pendidikan kewirausahaan bagi semua profesi yang dihasilkan oleh perguruan tinggi. Artikel ini ditulis berdasarkan pada hasil-hasil penelitian tentang pendidikan kewirausahaan di perguruan tinggi dan kajian literatur yang relevan. Artikel ini menyimpulkan bahwa pendidikan kewirausahaan di perguruan tinggi diperlukan dalam bidang apapun tanpa memperhatikan bidang yang ditekuni atau profesi seseorang. Kata kunci: wirausaha, kreativitas, values. Abstract: Entrepreneurship Education in Higher Education: Is that Important for All Profession? Entrepreneurship education has been developed in almost all universities in Indonesia. An entrepreneur is someone who exploits his/her creativity to create something valuable either in the form of tangible or intangible. That process can be carried out in his/her own company or in the organization where someone attached. The purpose of this article is to develop an understanding of the importance of entrepreneurship education for all professions. This study found that that entrepreneurship education in higher education is required in any field of study. Keywords: entrepreneurship, creativity, values

Hydrothermal treatment of empty fruit bunch and its pyrolysis characteristics

Abstract: Empty fruit bunch (EFB) is abundantly available for renewable energy resource, especially in Southeast Asian countries. However, EFB has inherent problems such as high moisture content, low heating value, and high alkali metal content. In order to improve the quality of feedstock as a fuel, in this research, the effects of hydrothermal treatment (HT) on the hydrothermally treated EFB (HT-EFB) characteristics were investigated. Also, the pyrolysis characteristics of EFB and HT-EFB were examined. The experiments of hydrothermal treatment were carried out in a 500-mL hydrothermal reactor at the temperature range of 120 to 220 °C with 60 to 120 min holding time. Afterward, the pyrolysis experiments of EFB and hydrothermally treated EFB (HT-EFB) were conducted in a lab-scale isothermal tube furnace at 400 °C for 1 h. The gas product was periodically collected to create gas evolution profiles. The result showed that hydrothermal treatment improved the properties of EFB, such as higher fixed carbon, lower ash content, and higher energy density. Hydrothermal treatment caused an increase in the heating value of HT-EFB to 19.47 MJ/kg, while the ratio of volatile matter/(volatile matter + fixed carbon) decreased from 0.82 to 0.68. Employing hydrothermal treatment in EFB did not only reduce the ash content of the biomass but also reduced the contents of potassium and sodium. In addition, the gas product from HT-EFB pyrolysis resulted in higher content of CO, CH4, and H2. The identified liquid product of pyrolysis consisted of alkane groups, phenolic groups, aromatic groups, ketones, acids, alcohols, and ester, which may be used as liquid fuel or for chemical production after further treatment. The observation indicated that hydrothermal treatment is an appropriate method to improve the fuel characteristic of EFB.