Gadjah Mada University

About: Gadjah Mada University is a education organization based out in Yogyakarta, Indonesia. It is known for research contribution in the topics: Population & Adsorption. The organization has 17307 authors who have published 21389 publications receiving 116561 citations. The organization is also known as: University of Gajah Mada & Universitas Gadjah Mada.

Methyl violet dye removal using coal fly ash (CFA) as a dual sites adsorbent

Abstract: It has become a trend to use cheap adsorbents like coal fly ash (CFA) for removal of dyes. CFA is a solid waste produced from coal-based power plant. CFA is mainly composed of minerals containing some oxides such as Al2O3 and SiO2 having active sites and mesoporous unburned carbon. The existence of active sites in the CFA's minerals and carbon pores was considered to have roles in the adsorption process with different adsorption mechanisms, namely chemisorption for the minerals and physisorption for the unburned carbon. This allows the CFA to become a dual sites adsorbent. As the result, isothermal models such as Langmuir and Freundlich may not be appropriate. The objectives of this study are to develop appropriate dual sites isotherm models for methyl violet dye adsorption onto the CFA, and to compare the models with single site models including Langmuir and Freundlich. The CFAs having [Si + Al]/C ratio of 0.5, 2.0 and 90, namely CFA-1, CFA-2, and CFA-3, respectively were used in this study. X-Ray Fluorescence (XRF) analysis results showed that the major components of the original CFA are SiO2 (36.47%) and Al2O3 (19.27%), while the unburned carbon content is 19.11%. Additionally, the adsorption test results showed that CFA with high unburned carbon contents (i.e. CFA-1 and CFA-2) were well fitted with the dual sites isotherm model, i.e. Freundlich–Langmuir isotherm model. Whereas, CFA with low unburned carbon contents (i.e. CFA-3) was well fitted with the single site isotherm model, i.e. Langmuir isotherm model.

Topical Timolol Maleate 0.5% for Infantile Hemangioma: Its Effectiveness Compared to Ultrapotent Topical Corticosteroids - A Single-Center Experience of 278 Cases

Abstract: Background: Infantile hemangioma (IH) may have implications on parental distress and cosmetic disfigurement. To date, ultrapotent corticosteroids are used as a tr

Active and intelligent packaging, safety, and quality controls

Abstract: Active and intelligent packaging in food can be classified as smart packaging that not only improves food protection and shelf-life, but also provides information regarding food safety and quality. Active packaging performs some active functions that could improve food quality and safety. These active functions, such as active scavengers and emitters, include absorption of oxygen, CO2, and ethylene. The gas emitters are like CO2 and SO2. Control of relative humidity, antioxidants release, absorbtion of undesirable odors, and antimicrobial function have also gained attention recently. Intelligent packaging provides information on the quality and environmental changes inside the packaging. The information on food quality is related to time and temperature, such as sensors or indicators for freshness, time-temperature, integrity, etc. The food quality is detected directly on pH or volatile compounds related to food degradation or microbial growth. While indirect detection is monitored by TTIs (time-temperature indicators) or RFID (radio frequency identification). This smart packaging is mainly used to minimize food losses, as it provides information on the quality and safety of the food throughout distribution till to display, including helping in distribution control, and the stock rotation system. This chapter reviews the current trends in active and intelligent packaging, including their applications for fresh-cut fruits and vegetables at the commercial level.