Authors:Khaoula Diass; Imane Oualdi, Mohammed Dalli, Salah-eddine Azizi, Mounir Mohamed, Nadia Gseyra, Rachid Touzani, Belkheir Hammouti Abstract: This study was conceived to work on Artemisia herba alba essential oils (EOs) originating from Eastern Morocco. We investigated the chemical properties and determined the antiradical scavenging activity. The GC-MS technique was used to elucidate the chemical composition of the two studied regions. Jerada Eo was distinguished by the existence of 1,6-Dimethylhepta-1,3,5-triene (36.44%), Camphor (22.50%), and Thujone (7.21%). While, Taourirt EO was found to be rich in Camphor (55.31%), Eucalyptol (14.64%), and Camphene (9.95%). Moreover, the free radical scavenging ability (DPPH•), and ferric reducing power assay (FRAP) were conducted. The EOs tested are found to be weakly active and to have important antioxidant potential. The docking study was also carried out by theoretical investigation with molecular docking of four active predominating components (1,6-dimethylhepta-1,3,5-triene; Chrysanthone; Eucalyptol; Alpha-pinene) against S protein of SARS-CoV‑2, and all the four ligands were found to bind to the S protein 6CS2 of SARS-CoV-2 differently and that the stable complex formed as a result of these interactions may prevent the binding of ACE2 with the spike S protein of SARS-CoV-2. PubDate: Tue, 20 Sep 2022 16:41:20 +070
Authors:Eka Sari; Andhika Puspito Nugroho, Endah Retnaningrum, Irfan Dwidya Prijambada Abstract: The objective of this study was to investigate the diversity of bacteria in the rhizosphere of Acacia grow in the forest and different ages of revegetated land and non-rhizospheric bacteria from active tin mining soil on Bangka Island with a metagenomic approach and to investigate its relationship with physicochemical properties of the soil and its metal content. 17 species/genera were found in the four fields, and Bradyrhizobium is the dominant genus. Bacterial communities of the forest (more than 5 years in revegetated post-tin mining land containing C, N, P, and Fe) are Paraburkholderia sp., Bacillus sp., Candidatus-Xiphinematobacter, and Bacterium enrichment. The physicochemical properties of soil from less than 5 years of revegetated contain Cu, Cr, and Mo, and the dominant species in this soil were Bulkhorderia sp., Bacillus lehensis, B. fordii, B. thermolactis, Chloroflexi bacterium, and Thermonosporaceae bacterium. The physicochemical properties of soil from the mining were dominated by Cd and Ni, and the dominant species in this soil were Sinomonas atrocyanea.
Authors:Yana A. Svakhina; Marina E. Titova, Igor N. Pyagay Abstract: The article presented the results of studies on the production of low-modulus zeolites from two types of technogenic resources containing a sufficient amount of silicon in their composition. The raw materials were nepheline concentrate and silica gel, which are products of the processing of apatite-nepheline ore. Directly before the synthesis of low-modulus zeolites, the morphology, chemical composition, and particle size of the starting materials were analyzed. The optimal parameters for sample preparation and purification of the raw materials used were also selected. The influence of the ratio of components in the reaction mixture on the type of synthesized zeolite and its characteristics were studied. The properties of synthesized zeolites from the proposed type of raw material were compared with the properties of zeolites synthesized today using the popular technology from kaolin clay, which is currently offered as an inexpensive natural raw material.
Authors:Yu. L. Zhukovskiy; B. Y. Vasilev, N. A. Korolev, Y. M. Malkova Abstract: The article was devoted to the study of an automated electric drive with a scalar closed-loop speed control system. Severe duty and operating modes of electric drive determine the actual service life. Wear of the induction motor, as a key link of the electric drive, was associated with deviation from nominal parameters. The deviation of parameters of the induction motor equivalent circuit determined the resultant change of characteristics. The parameters of the equivalent circuit determined the accuracy of the adjustment of regulators and optimal algorithms in the control system of the electric drive. In continuous operation modes the possibility of auto-tuning regulators, which requires stopping or no-load mode, was excluded. The paper considered the influence of the magnetization circuit mutual inductance value of the induction motor on the behavior of the electric drive control system. Evaluation of the behavior of the scalar closed-loop speed control system was performed on the basic energy (power factor, efficiency factor) and mechanical (speed, electromagnetic torque) characteristics of the electric drive.
Authors:Yazan Alaya Al-Khassawneh Abstract: Artificial intelligence has the potential to address many societal, economic, and environmental challenges, but only if AI-enabled gadgets are kept secure. Many artificial intelligence (AI) models produced in recent years can be hacked by utilizing cutting-edge techniques. This issue has sparked intense research into adversarial AI to develop machine and deep learning models that can withstand various types of attacks. We provide a detailed summary of artificial intelligence in this paper to prove how adversarial attacks against AI applications can be mounted, covering topics such as confrontational knowledge and capabilities, existing methods for actually producing adversarial examples, and existing cyber defense models. In addition, we investigated numerous cyber countermeasures that could defend AI applications against these attacks and offered a systematic approach for demonstrating war strategies against machine learning and artificial intelligence. To safeguard AI applications, we emphasize the importance of understanding the intentions and methods of possible attackers. In the end, we list the biggest problems and most interesting research areas in the field of AI privacy and security.
Authors:Rinny Jelita; Iryanti Fatyasari Nata, Chairul Irawan, J. Jefriadi, Meda Nur Anisa, Muhammad Jauhar Mahdi, Meilana Dharma Putra Abstract: Lignite is classified as a low-rank coal due to its low content of calories. Co-pyrolysis with biomass waste such as palm empty fruit bunches (EFB) here can be used to increase lignite’s economic value. The mixture of these two materials can produce an alternative energy source called hybrid coal (HC). This study aims to determine the optimum temperature for co-pyrolysis of lignite and EFB as well as characterize liquid (tar) and solid product (HC). Its kinetic study was evaluated as well. A raw material of 200 grams with a composition of 22.5% (w/w) EFB to lignite was put into a reactor to react at a temperature range of 300-450oC for 1 hour. To form hybrid coal briquettes (HCB),tapioca adhesive with a concentration of 6% (w/w) was added to the solid product (HC). The results showed that the tar yield increased with increasing temperature from 300 to 450oC. Similarly, the calorific value of HC increased by 14.50% as also occurred in other physical properties of HC. Meanwhile, the kinetic study revealed that the model was well-fitted to the data, and confirmed the obtained results. Thus, this research can support the development of affordable alternative energy to be implemented in large-scale production.
Authors:Asep Bayu Dani Nandiyanto; Risti Ragadhita, Meli Fiandini Abstract: Fourier transform infrared (FTIR) is one of the tools to represent molecular structure based on atomic vibration. It can denote a specific property of the chemical bond and molecular structure in the material, especially when analyzing specimens relating to plastics, polymers, and organic components. The FTIR peaks and spectrum act as a fingerprint of a specific molecular structure and chemical bonding, which need a sufficient reference database to distinguish them. This paper is to address issues of the need for a reference database of FTIR. This paper exhibits step-by-step information on how to read and interpret the FTIR spectra and identify a molecule's backbone with its functional groups. Practical examples from the analysis of several plastics/polymers and the thermally decomposing plastics/polymers were included to help and guide the reader to comprehend the basic concept of FTIR spectra.
Authors:W. Wagiran; M. Mujiyono, Bayu Rahmat Setiadi, Yulianto Eko Wibowo, Fredy Surahmanto, Dendy Aqila Agata, Chinnathan Areeprasert Abstract: This paper aims at developing the potential of cellulose-based energy generation using pyrolysis, gasification, and combustion methods with biodegradable waste media. The cellulose-based material used in this study was sawdust. The sawdust was heated using a biomass stove, which was then analyzed in terms of heat conduction and propagation as well as temperature distribution. To ensure the effectiveness of sawdust as the main material in the biomass stove, sawdust particles were pressed and compacted under various pressure conditions. This experiment was integrated with the Project-Based Learning method through the following steps: (1) determination of projects testing, (2) project design, (3) project implementation schedules, (4) project completion and progress monitoring, (5) reports and presentations of project results, and (6) project evaluation. The results provide new findings that the denser sawdust particles correlate with the greater temperature and propagation rate. This can be obtained from the measured temperature distribution. Areas close to the heat source tend to have the same heat propagation. The density of the sawdust particle is the main key point for producing better pyrolysis and gasification process, in which it correlates with long combustion energy. Integrasi This finding opens a new concept and can be used as a reference for other researchers who develop research related to renewable energy from waste, especially when using a biomass stove. This study also gives ideas for the need for developing project-based learning using the burning of sawdust using biomass stove as a tool for the teaching and learning process.
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