Low-Mass Liquid Crystalline Materials Blended in Recycled Thermoplastic Polyester Elastomer for Corrosion Inhibitor Application

In this work, the development and application of multicomponents obtained from recycled polyethylene terephthalate (r-PET) waste and monotropic liquid crystals as anticorrosion coatings are reported. The r-PET raw material was alcoholyzed and reproduced as a thermoplastic polyester elastomer (TPEE) with different amounts (n%, n = 0, 1, 3, and 5) of 1,6-hexanediamine (HDA). Then, a fluorine-containing liquid crystal (4-cyano-3-fluorophenyl 4-ethylbenzoate (4CFE)) was incorporated into the TPEE mixture via solvent blending to modify and enhance the water resistance. The adhesion behavior of the coating on glass and iron substrates was evaluated by cross-cut tests and immersion tests in aqueous NaCl. In the corrosion resistance measurements, all of the coating samples fabricated with 10 ± 1 mm thickness were less active toward electrochemical corrosion (PEF% > 99%) than the bare iron plate, indicating that our work provided better protection against corrosion of the iron plate.

Turkestan Cockroaches Avoid Entering a Static Electric Field upon Perceiving an Attractive Force Applied to Antennae Inserted into the Field

This study analysed the mechanism of avoidance behaviour by adult Turkestan cockroaches (Shelfordella lateralis Walker) in response to a static electric field (S-EF) formed in the space between a negatively charged polyvinyl chloride-insulated iron plate (N-PIP) and a grounded metal net (G-MN). The negative surface charge supplied to the iron plate by a voltage generator caused the G-MN to polarise positively via electrostatic induction. In the S-EF, the negative charge of the N-PIP created a repulsive force that pushed free electrons in the field toward the ground via the G-MN. When insects released in the space surrounded by the S-EF inserted their antennae into the S-EF, they pulled them back reflexively and moved backward. The analysis indicated that an electric current flowed transiently toward the ground when an insect inserted its antennae into the S-EF. The insect became positively charged via this discharge and was attracted to the opposite pole (N-PIP). In response to this attractive force, the insect pulled its antennae back quickly. The positive electrification caused by the removal of free electrons from the antenna tip triggered the avoidance behaviour.

GAMELAN SELONDING CHRICAL FUNCTIONS IN TENGANAN PEGRINGSINGAN VILLAGE

This paper aims to study and understand the sacredness of the Salonding gamelan in Tenganan Village in its context with religious rituals and the people of Tenganan Village as protection. Gamelan Selonding in Tenganan Village has its own history, its existence is associated with stories or myths that have been passed down from generation to generation. The approach used is semiotic through interpretive analysis of texts and contexts that support the culture concerned. The research found that, starting with the discovery of three iron plate blades which were declared as Selonding gamelan blades. Believed to be a descent that is not made by ordinary humans, but because of the gift of nature, the people of Tenganan Village are called 'Bhatara Bagus Selonding'. Gamelan Selonding for the people of Tenganan Village is very sacred. In maintaining its sacredness it is adjusted to the concept of the village, kala, and patra, not to be touched by other people, except by members of the selected art group (Gambe) with seven members. Gambel juru has the responsibility to maintain the sanctity of the Selonding gamelan. For the people of Tenganan Village, the sacredness of the Selonding gamelan is not just an outward statement, but a totality that represents the integration of people's thoughts, feelings, speech and attitudes, so that the treatment of Selonding is prostration. So, Selonding for the people of Tenganan village, is not just a medium of artistic expression but a representation of religiosity so that selonding is sacred and sanctified. Keywords: Gamelan Selonding, representation, art, religiosity

Theoretical investigations on the linear and nonlinear damping force for an eddy current damper combining with rack and gear

To study the damping characteristics of a new type of eddy current damper with rack and gear recently proposed by the authors, the damping torque for the eddy current damper with rack and gear was theoretically investigated based on some fundamental assumptions, including evenly distributed magnetic field on a conductor plate and no magnetic leakage. A linear relationship between damping torque and velocity was obtained. Numerical simulations by using COMSOL Multiphysics were conducted to evaluate the accuracy of the linear theoretical formula. When angular velocity is less than 30 rad/s, it seems that the linear theoretical results agree well with the numerical results, and maximum relative error between them is about 6.58%. Then, by using COMSOL Multiphysics, a series of parametric studies on damping torque, including the effects of the air gap, the thickness of a back iron plate, the location and number of permanent magnets, and the thickness of a conductor plate, were carried out to further examine the linear theoretical formula. The results show the effects of the air gap and back iron plate on the relative error between linear theoretical and numerical results can be ignored, whereas the location and number of permanent magnets and the thickness of the conductor plate have significant influences on the relative error. Finally, a nonlinear theoretical formula was obtained by introducing three modified coefficients into the linear theoretical formula, and its accuracy was verified in some typical cases. It is proved that there is sufficient accuracy to adopt the nonlinear theoretical formula in preliminary design of the eddy current damper with rack and gear to determine the main structural parameters.

Use of Electric Discharge for Simultaneous Control of Weeds and Houseflies Emerging from Soil

An electrostatic apparatus was developed to control weeds and houseflies emerging from ground soil in a greenhouse simultaneously. Identical iron plates were placed in parallel at a defined interval and fixed in an iron frame. Two sets of fixed iron plates were used, one for weed control and one for fly control. For weed control, all of the iron plates were negatively charged, and negative charges accumulated on the plates were released to weed shoots through arc discharge. Houseflies were introduced into the space between the negatively charged and grounded plates, then subjected to arc discharge from the charged plates. Both plant shoots and adult houseflies are electrically conductive; thus, they were killed by discharge-exposure in the electric field between the charged iron plate and the ground soil, and between the charged and grounded plates, respectively. In practical use, these two devices were assembled as a two-level apparatus for simultaneous control of both targets. Several apparatuses were linked together, which increased the total electricity charge on the plates and produced a stronger discharge force sufficient to kill all targets. Thus, this study provides an electrostatics-based pest-control method for pesticide-independent greenhouse farming.

UJI EFEKTIVITAS GEL KOMBINASI EKSTRAK ETANOL DAUN BANGUN-BANGUN (Coleus amboinicus L.) DAN DAUN KELAPA SAWIT (Elaeis guieensis Jacq) SEBAGAI OBAT LUKA BAKAR TAHUN 2020

Coleus amboinicus L leaves and Elaeis guieensis Jacq leaves contain various secondary metabolites such as saponins, tannins, alkaloids and flavonoids that function in wound healing. The purpose of this study was to determine the healing effect of burns using a gel preparation combination of ethanolic extract of Coleus amboinicus L. (EECAL) And ethanolic extract of Elaeis guineensis Jacq. (EEEGJ) In healing burns. Coleus amboinicus L leaves and Elaeis guieensis Jacq leaves contain are separated from the petiole and then dried in a drying cupboard so that it becomes a simplicia. Simplisia is extracted by maceration method then evaporated with a rotary evaporator and evaporated again on a water bath to produce a thick extract. EECAL and EEEGJ are then formulated into gel preparations with varying concentrations. Each rabbit was shaved on its back then cleaned with 70% alcohol. Furthermore, rabbits were anesthetized using 0.5 ml Lidocain HCL as much as 0.5 ml subcutaneously. Then mark the part that will be injured with a diameter of 2 cm, by lifting the rabbit skin using tweezers and then made a wound using a hot iron plate that has been sterilized beforehand with 70% alcohol. Wound diameter measurements showed that all treatment groups from day 1 to day 20 experienced changes in wound diameter. EECAL 15% and EEEGJ 10% have a more effective effect in healing of burn than in their single form.