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One of the agricultural commodities in Indonesia which is quite large is onion. Shallots are agricultural commodities that are easily damaged, such as softening, wrinkles, porous, rotting, sprouting, and fungal growth. Damage to shallots causes a decrease in quality and selling value. Therefore, proper post-harvest handling is needed. One of them is in the drying process before storage, marketing, and processing. The use of an automatic drying machine using an Arduino Uno-based tray dryer system is one solution for the onion drying process. This drying machine is equipped with a temperature sensor that will send a signal to the microcontroller and proceed to the solenoid. At a certain temperature, the stove will turn off and on automatically. The machine is also equipped with a timer system so that the production process will get the same results. The most suitable temperature for the shallot drying process is 45ᵒ-75ᵒ C. Drying with a temperature below 45℃ will cause damage to the shallots because the fungi and microbes are still alive so that it can reduce the quality. Drying at temperatures above 75℃ can cause poor physical and chemical structure due to high heat transfer. [ABSTRACT FROM AUTHOR]

In petroleum refinery plant, the stabilizer column is a crucial part in supporting the production process. In the present study, we found that the stabilizer column was not in optimal condition, hence, the internal structure is necessary to be investigated. Gamma scanning is one of the most effective and efficient techniques for investigating and observationof the column's quality in petroleum refinery plants. This study aimed to investigate the use of the gamma scanning method to analyze the presence and condition of the tray inside the stabilizer column. The column (20,600 mm in height) has 25 trays inside, consisting of 11 single passes in the upper (ID: 1,100 mm) and 14 double passes in the lower (ID: 2,100 mm)segment. Scanning was carried out by placing the radiation source (Co-60, with the current activity of 1.77 GBq) and the detector (NaI(TI)) outside the column on opposite sides, then scanned from the bottom to top with 50 mm intervals at each data point and 2 s scanning time using gamma counter module (Ludlum). Scanning was carried out with 2 orientations and 1 orientation at the lower and the upper segment, respectively. Results showed that trays #1-#25 were in their positions, however, trays #12, #15, #19, and #25 were suspected of slight foaming, and tray #5 was suspected of slight weeping. There was an indication of liquid entrainment on trays #1 and #8. The presence and condition of the trays inside of the stabilizer column have been investigated using the gamma scanning technique without disturbing the production process. The results of the present study can be used as a reference or recommendation in preparing the turnaround maintenance (TAM) efficiently. [ABSTRACT FROM AUTHOR]

Drying aims to maintain durability by reducing the water content in the product. Ripe plantains have high water and sugar content, so they require special handling. This study dried ripe plantain chips using three rack-type dryers with different characteristics and heating sources. Two dryers used in this study were an electric tray dryer (P2) and a gas-burner type tray dryer (P3) developed by Research Center for Appropriate Technology, and the rest was a commercial electric tray dryer (P1). This experimental study used a factorial randomized design method with two factors: the dryer and the tray's position in the drying rack. The purpose of this study was to evaluate the performance of a pilot plant-scale rack-type dryer with different characteristics and heating sources for drying ripe plantain chips. The research found that the three dryers reduced the moisture content of fresh plantain from 57.9–62.9% to 4.61%–10.34% after becoming dry chips. Analysis of temperature stability and uniformity in the drying chamber during the drying process showed that the gas-burner type tray dryer (P3) was more stable and had a uniform drying temperature compared to the commercial electric tray dryer (P1) and the electric tray dryer (P2). Meanwhile, based on the drying results, the moisture content of the banana chips from the commercial electric dryer (P1) was the highest and significantly different from the other two dryers. The results indicate that all evaluated dryers can dry ripe banana chips with good results. [ABSTRACT FROM AUTHOR]

Ehis article deals with the problem of choosing a function to approximate creep curves in order to predict the deformation of the structure of a drainage trays made of composite materials. We come to the conclusion about the most accurate function and the minimum required time for testing for creep the drainage trays made of composite materials. [ABSTRACT FROM AUTHOR]

Iron (Fe) in the drinking water is an essential ion needed by the body. However, if the iron ion levels in the body exceed, it will cause health problems such as damage to the intestinal wall. This study aims to analyze the tray aerators in reducing iron in drinking water. This research is experimental design with the various height of the tray aerator (1 m, 1.5 m, and 2 m) and sedimentation time (1 h, two h and three h) by a continuous system. Statistical analysis using the two-way ANOVA test to determine the mean difference between treatments group with an error rate (α) of 5%. The lowest iron level in drinking water was 0.218 mg/l for a tray aerator of 2 m in height. Furthermore, the lowest iron level was 0.205 mg/ l for a sedimentation time of 3 h. There was a significantly different mean level of iron between the groups based on the tray aerator's height and sedimentation time (p < 0.05). Tray aerator with a height of 2 m and sedimentation time of 3 hours reduce the iron level in drinking water to meet the drinking water standards. [ABSTRACT FROM AUTHOR]

Flexible plastic films from food packaging trays make up one of the largest fractions of the plastic waste stream and recycling is one of the most important actions to deal with this fraction, reducing the impact of these plastics on the environment. However, the recyclability of multi-layered films is not straightforward and in most of the cases these fractions are landfilled or incinerated. Recycling of discarded mixed polymers without previous separation often results in low mechanical properties which have lead researchers to investigate novel solutions for recycling. In this research, the concept of microfibrillar composites (MFCs) was investigated aiming to upcycle mixed polymer waste streams. A blend based on polypropylene (PP) and poly(ethylene terephthalate) (PET) at a weight ratio of 80/20 PP/PET was studied. The final step of the MFC processing was conducted using a conical twin screw extrusion. The morphological results confirmed the presence of PET microfibrils in the composites, leading to an improvement in mechanical properties such as in the tensile yield strength and strain at break. Subsequently, the MFC samples were successfully moulded into trays via thermoforming. [ABSTRACT FROM AUTHOR]

Plastics that are renewable and biodegradable have become increasingly popular in the quest for greener and more sustainable food packages. These so-called bioplastics are designed to replace traditional petrochemical polymers with renewable natural resources. To be a viable alternative to these oil-based resources the material must be successfully integrated into existing mass-manufacturing processes that transform material sheets into three-dimensional products. The purpose of this study was to examine the effect of process parameters, particularly moulding temperatures, on the 3D-formability of bioplastics during thermoforming. A numerical/visual comparison was conducted between thermoformed tray packages and reference packages made of petrochemical polymers focusing primarily on product geometry and stiffness. Three bioplastic materials were selected based on their availability and suitability for the process: Polylactic Acid (PLA) and Cellulose Acetate Propionate (CAP). The sample materials were formed to specimen trays using a custom-designed sheet-forming chamber on a commercial Form-Fill-Seal (FFS) thermoforming line. Material changes necessitated separate optimizations of the process parameters for each material. It was found that the material properties of bioplastics set certain limits to the formed geometric shapes, but these limits can be addressed during the packaging design phase, making bioplastics a viable material for environmentally friendly yet economically feasible packages. [ABSTRACT FROM AUTHOR]

Noise also known as a sound, especially one that is loud or unpleasant or that causes disruption. The level of noise can be reduced by using sound absorption panel. Currently, the market produces sound absorption panel, which use synthetic fibers that can cause harmful effects to the health of consumers. An awareness of using natural fibers from natural materials gets attention of some parties to use it as a sound absorbing material. Therefore, this study was conducted to investigate the potential of sound absorption panel using egg trays and kapok fibers. The test involved in this study was impedance tube test which aims to get sound absorption coefficient (SAC). The results showed that there was good sound absorption at low frequency from 0 Hz up to 900 Hz where the maximum absorption coefficient was 0.950 while the maximum absorption at high frequencies was 0.799. Through the noise reduction coefficient (NRC), the material produced NRC of 0.57 indicates that the materials are very absorbing. In addition, the reverberation room test was carried out to get the value of reverberation time (RT) in unit seconds. Overall this panel showed good results at low frequencies between 0 Hz up to 1500 Hz. In that range of frequency, the maximum reverberation time for the panel was 3.784 seconds compared to the maximum reverberation time for an empty room was 5.798 seconds. This study indicated that kapok fiber and egg tray as the material of absorption panel has a potential as environmental and cheap products in absorbing sound at low frequency. [ABSTRACT FROM AUTHOR]