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Dynamic kinetic data collected over commercial V2O5-WO3/TiO2 and Fe-zeolite catalysts analyzing the standard NH3-SCR of NO for the abatement of NOx from vehicle exhausts showed transient effects at low temperatures related to the inhibiting action of excess ammonia. In order to describe such transient effects, a specific rate expression accounting for NH3 inhibition of the standard SCR reaction is needed in mathematical models of real SCR converters. We present herein a dual-site Mars-Ven Krevelen-type rate equation suitable to describe dynamic features associated with ammonia injection and shut-off over both V-based and Fe-zeolite catalysts. Les données cinétiques dynamiques recueillies sur des catalyseurs V2O5-WO3/TiO2 et Fe-zéolite commerciaux en analysant le RCS-NH3 standard du NO pour la réduction des NOx des gaz d’échappement de véhicules ont montré des effets transitoires à basse température, liés à l’action inhibitrice d’ammoniac en excès. Afin de décrire de tels effets transitoires, une expression de la vitesse spécifique prenant en compte l’inhibition par NH3 de la réaction de RCS standard est nécessaire pour des modèles mathématiques de convertisseurs par RCS réels. Nous présentons ici une équation de vitesse de type Mars-Van Krevelen à double site pour décrire les caractéristiques dynamiques associées à l’injection et à l’arrêt de l’ammoniac sur des catalyseurs à la fois à base de V et Fe-zéolite.

The agricultural industry is critical in supplying food and fiber demands, but there is a demand-supply imbalance due to decreased land availability. Hydroponic techniques can be utilized to alleviate agricultural land loss by using water as a growing medium. Farmers must constantly examine plant condition and harvesting schedules. The pH of the water and nutrients are important indications for hydroponic farmers to monitor. Therefore, the implementation of the Internet of Things (IoT) allows farmers to conduct real-time monitoring more easily and regularly. IoT is defined as a system that allows integrated hardware to communicate with the internet network. The IoT device is built by attaching a NodeMCU 8266 microcontroller to an adapter, which provides electrical voltage while also regulating a water pump that delivers nutrients and water to plants. The acquired data is then transmitted to the blynk program, allowing real-time monitoring of the results via a smartphone. The present research system's usefulness and performance are improved by including pH and TDS sensors. The average accuracy of pH monitoring utilizing a pH sensor and a manual pH meter was 92.09%. Meanwhile, the average accuracy of nutrient monitoring utilizing TDS sensors and a TDS meter was 73.19%.

The COVID-19 pandemic that is currently happening in Indonesia has had a major impact in all fields, one of which is education. In this pandemic period, education in Indonesia must be carried out online, which results in the inhibition of direct interaction between teachers and students. Therefore, the Ministry of Education and Culture organizes a Teaching Campus program, which is part of the Independent Learning Campus (MBKM) policy. This Teaching Campus Program aims to provide solutions for elementary schools affected by the pandemic by empowering students who live around the school area to assist teachers in carrying out learning activities in the midst of the COVID-19 pandemic. The results of the study show that the implementation of the Class 2 Teaching Campus at Public Elementatry School 04 of Purwosari includes the following: First, teaching is carried out by home visits, through online media, and face-to-face (after limited PTM verification). Second, technology adaptation by helping teachers prepare materials sent via WhatsApp media, and third, assisting administration in the form of allocating textbooks in libraries and collecting student data.

Reduction of NO by NH3 over metal-promoted zeolites represents the principal reaction in the selective catalytic reduction (SCR) technology for NOx removal from Diesel engine exhausts. It has been established that addition of ammonium nitrate (AN) to the reaction mixture substantially enhances the rate of this reaction, decreasing the temperature necessary for an efficient deNOx process. Nevertheless, the nature of this effect has not been completely elucidated. To investigate the NO + AN reaction mechanism, we have used individual reactants labeled with either 15N or 18O (or both isotopes), thus obtaining an experimental background for proposing the route of the SCR accelerated by AN addition. For this study, we have used as the catalysts H-BEA and Fe/H-BEA zeolites with various Si/Al ratios and various amounts and states of the iron species. [ABSTRACT FROM AUTHOR]

This paper discusses trends, challenges, and perspectives in logistics system of Indonesia during and post (new normal) of Covid-19 pandemic. PSBB (Large-Scale Social Restriction) caused a number of supply chains to be cut and made railroad transportation activities decreased. On the other hand, WFH (Work From Home) caused sector of e-Commerce to grow during the pandemic. Challenges in logistics system of Indonesia during the pandemic are changes in distribution patterns, changes in handling processes, changes in facilities and equipment, changes in business processes, and changes in networks. Adaptations in logistics system during the pandemic are using ICT (information and communication technology) such as TMS (Transportation Management System) and EDI (Electronic Data Interchange) and considering health. WMS (Warehouse Management System) still has a great opportunity to be utilized. The adaptations raise a new discipline in Industrial Engineering, namely logistics hygienic. The use of various ICTs in logistics system together with implementation of health protocols are expected to be a solution for logistics system in Indonesia, especially for the new normal of Covid-19 pandemic.