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Open Access

Review

14 November 2023

Microgrids Overview and Performance Evaluation on Low-voltage Distribution Network

Besides the increase in global energy demand, access to clean energy, reduction in greenhouse gas emissions caused by conventional power generation techniques, energy security, and availability of electricity in remote villages in emerging nations are some of the factors that foster the use of renewable energy sources (RESs) in generating electricity. One of the aims of initiating microgrids (MGs) is to maximize the benefits of RES while alleviating grid-connect issues. Microgrids are interconnected RESs and electrical loads within clearly delineated electrical limits that operate as individual controllable units on the electrical network. It can operate independently and be grid-connected. The paper presents a review and performance assessment of renewable energy-based microgrids under various operating scenarios in stand-alone, grid-connected, and transitioning modes of operation. Fault occurrences, an increase in micro-source generation, a load increase, and the sudden disconnection of a micro-source are some of the simulated scenarios. Microgrid network components’ performance, such as the bidirectional DC-DC converter and energy storage system (ESS), was evaluated. The simulated microgrid architecture includes a small hydroelectric plant, wind farm, and ESS. The work provides valuable information to energy stakeholders on the performance of microgrids in low-voltage distribution networks. The microgrid is coupled to a low-voltage distribution network (0.415 kV) via a PCC. The system under investigation is modeled and simulated using MATLAB/Simulink. From the simulation analysis, the fault effect was felt on the utility and did not escalate to the microgrid side during stand-alone operation. Power quality issues, such as voltage rise, are some of the challenges identified during the transition from one mode of operation to another. However, the energy storage system responds to disturbances and maintains system stability. The originality of this paper is based on evaluating different modes of operation of microgrids and comparing system performances under various operating conditions.

Keywords: Microgrid; Small hydropower plant; Wind farm; Battery energy storage systems; Grid-connected; Stand-alone mode; Power quality 
Clean Energy Sustain.
2024,
2
(1), 10008; 
Open Access

Editorial

08 November 2023
Open Access

Review

08 November 2023

Review on Drone-Assisted Air-Quality Monitoring Systems

Drone-aided systems have gained popularity in the last few decades due to their stability in various commercial sectors and military applications. The conventional ambient air quality monitoring stations (AAQMS) are immovable and big. This drawback has been significantly overcome by drone-aided low-cost sensor (LCS) modules. As a result, much research work, media information, and technical notes have been released on drone-aided air quality and ecological monitoring and mapping applications. This work is a sincere effort to provide a comprehensive and structured review of commercial drone applications for air quality and environmental monitoring. The collected scientific and non-scientific information was divided according to the different drone models, sensor types, and payload weights. The payload component is very critical in stablility of the multirotor drones. Most study projects installed inexpensive sensors on drones according to the avilibility of the space on drone frame. After reviewing of multiple environmental applications the common payload range was 0 gm to 4000 gm. The crucial elements are addressed, including their relation to meteorological factors, air isokinetics, propeller-induced downwash, sensor mounting location, ramifications etc. As a result, technical recommendations for AQ monitoring assisted by drones are addressed in the debate part. This work will help researchers and environmentalists choose sensor-specific payloads for drones and mounting locations. Also, it enables advanced methods of monitoring parameters that help policymakers to frame advanced protocols and sensor databases for the environment and ecology.

Keywords: Drones; Air quality; Ecology and environment; Sensors
Drones Veh. Auton.
2024,
1
(1), 10005; 
Open Access

Article

07 November 2023

Use of Bibliometric Methods to Verify the Credentials of Expert Witnesses in Forensic Science and Legal Medicine and the Dilemma of Multiple-authorship

Expert testimony is an important part of criminal and civil litigation whenever scientific evidence needs to be explained and interpreted for the judge and jury. Those appearing in court as expert witnesses must possess the necessary qualifications, skill, training, and experience for the task in hand. Unlike a lay-witness, an expert witness is allowed to render an opinion based on their own specialized knowledge and research. In the adversarial system of justice, expert witnesses are hired by opposing sides in a case and this causes confusion when they disagree about the strengths and weaknesses of the scientific evidence presented. Choosing the best expert witness is often a difficult task and making a wrong decision has sometimes led to wrongful convictions and miscarriages of justice. Success in science is tightly linked to the quantity and quality of a person’s scholarly publications in academic journals in some particular area of research and scholarship. This article describes the use of a publicly available citation database to investigate the publication and citation records of British forensic practitioners with “legal and forensic medicine” (LFM) as their primary or secondary research category. How to attribute credit to individual names on multi-authored articles is a major problem in science and academia. Six different citation metrics, including authorship position on highly cited articles, were used to derive a composite citation score (c-score) for each highly cited scientist. Such bibliometric methods could prove useful in jurisprudence when reviewing the qualifications of people suggested to serve as expert witness in court cases.

Keywords: Authorship; Bibliometrics; Citation analysis; Expert evidence; Forensic science; Legal medicine; Scholarly publishing
Perspect. Legal Forensic Sc.
2024,
1
(1), 10002; 
Open Access

Review

31 October 2023

Metabolic Engineering of Microorganisms Towards the Biomanufacturing of Non-Natural C5 and C6 Chemicals

Five-carbon (C5) and six-carbon (C6) chemicals are essential components in the manufacturing of a variety of pharmaceuticals, fuels, polymers, and other materials. However, the predominant reliance on chemical synthesis methods and unsustainable feedstock sources has placed significant strain on Earth’s finite fossil resources and the environment. To address this challenge and promote sustainability, significant efforts have been undertaken to re-program microorganisms through metabolic engineering and synthetic biology approaches allowing for bio-based manufacturing of these compounds. This review provides a comprehensive overview of the advancements in microbial production of commercially significant non-natural C5 chemicals, including 1-pentanol, 1,5-pentanediol, cadaverine, δ-valerolactam, glutaric acid, glutaconic acid, and 5-hydroxyvaleric acid, as well as C6 chemicals, including cis, cis-muconic acid, adipic acid, 1,6-hexamethylenediamine, 6-aminocaproic acid, β-methyl-δ-valerolactone, 1-hexanol, ε-caprolactone, 6-hydroxyhexanoic acid, and 1,6-hexanediol.

Keywords: Metabolic engineering; Renewable feedstock; Bio-based chemicals; C5 chemicals; C6 chemicals
Synth. Biol. Eng.
2023,
1
(3), 10015; 
Open Access

Editorial

30 October 2023
Open Access

Article

17 October 2023

The Severity of Isoproterenol-Induced Myocardial Fibrosis and Related Dysfunction in Mice Is Strain-Dependent

The isoproterenol (or isoprenaline; ISO)-induced model of myocardial injury provides a non-surgical means of establishing features of dilated cardiomyopathy (DCM) in various species, including left ventricular (LV) inflammation, cardiomyocyte hypertrophy, vascular rarefaction, fibrosis and related dysfunction. However, when established in mice, the progression and severity of the LV fibrosis that manifests in this model can be affected by the exposure time and/or dosing of ISO applied, and by strain when an equivalent exposure time and dose are administered. In this study, we measured the severity of LV fibrosis by biochemical and histological means in 129sv, C57BL/6J and FVB/N mice exposed to repeated ISO (25 mg/kg for 5 days) administration at 14-days post-injury. At the time-point studied, these strains of mice underwent a ~2-fold, ~0.7-fold and ~0.3-fold increase in LV collagen concentration, respectively, compared to their saline-injected controls; whilst 129sv and C57BL/6J mice underwent a corresponding ~7-fold and ~1-fold increase in picrosirius red-stained interstitial LV collagen deposition, respectively. C57BL/6J mice subjected to higher dosing of ISO (50 or 100 mg/kg for 5 days) underwent a ~1.4–1.6-fold increase in picrosirius red-stained interstitial LV collagen deposition and some LV systolic dysfunction at day-14 post-injury, but the fibrosis in these mice was still less severe than that measured in 129sv mice given a lower dose of ISO. These findings highlight that strain-dependent differences in ISO-induced LV fibrosis severity can impact on evaluating pathological features of DCM and the therapeutic effects of anti-fibrotic drugs/strategies in this model.

Keywords: Dilated cardiomyopathy; Myocardial fibrosis; Systolic dysfunction; Isoproterenol; Mouse strain
Open Access

Review

12 October 2023

New Trends on Photoswitchable Antibiotics: From Syntheses to Applications

Antibiotics are excreted in the environment after being used to treat bacterial infections in human and animals. These residues are poorly eliminated by the actual wastewater treatment processes, affecting animal, human and environmental health. This has led to the emergence of antibiotic resistance in bacterial pathogens. To combat this problem, photopharmacology has emerged in the last decades. This approach, based on the coupling of a drug with a photochromic component, is a promising way to control antibiotic activity by light irradiation and consequently limit antibioresistance. Thus, this review summarizes the study on the effect of the irradiation light on the antimicrobial activity of coupling compounds.

Keywords: Photopharmacology; Antibacterials; Medicinal chemistry; Physicochemistry
Photocatal. Res. Potential
2024,
1
(2), 10007; 
Open Access

Article

12 October 2023

Risk Analysis of Crisis Management on the Example of Rural Areas in Poland

The aim of this article is to analyze and assess the risk of crisis hazards and to introduce possible improvements on the example of the Municipality of Branice. The types of threats and the consequences associated with their occurrence are also described. The quality management method (FMEA) was used to develop the risk assessment, as well as an indication of the risk values presented by the risk matrix made. Thanks to the research part of the study, the most probable possible risks and their consequences were detected, and improvements were proposed to prevent the occurrence of such situations in the future. The main conclusions of the study are: (1) a properly prepared crisis management plan is the most important and effective method to deal with emergencies that threaten the life and health of citizens; (2) hazards have been, are, and will continue to accompany people, so adequate preparation is needed to minimize their effects or even eliminate them altogether; (3) during the occurrence of an emergency, the sphere of logistical action is very broad and determines the methods and actions of the relevant services in order to reduce the effects of the threats that occur; (4) the conducted analysis of threats possible to occur in the area of Branice Commune indicates that the highest probability of occurrence of a threat is floods and waterlogging as well as hurricanes and strong winds; (5) the conducted FMEA analysis indicates that a very important factor preventing the creation of the threats discussed in the point above are periodical inspections and cleaning or modernization works of the given threat areas. In summary, the FMEA analysis showed that in the analysed municipality, the most serious risks were flooding and flooding, as well as hurricanes and high winds. The following remedial actions are proposed in the analysis and to improve these areas in the rural areas: water surge in the riverbed (cleaning of the riverbed; repair of dikes; securing roads and communication bridges against possible damage; securing drinking water reservoirs against pollution; securing sewage treatment plants against possible leakage of faecal matter into flood waters); obstruction of field drainage (regular mowing and cleaning of ditches; checking the patency of ditches; roofs of residential and commercial buildings and fallen trees in villages close to houses (inspections and pruning of dangerous tree branches and possible removal of trees threatening danger of falling; inspection of roof structures by building supervision) and fallen trees in riverbeds (cleaning of banks and riverbeds; inspection of tree stands near rivers). The policy implications of this study may be far-reaching, not least because it may determine rural managers to change their management and attention to and response to crisis threats that may occur in such areas. Regarding the limitations of the study, it is important to remember that it was conducted on the author’s chosen terrain. In most cases, changes in the terrain, the population or its management have a determining influence on the shaping of emergency response principles. Therefore, the study conducted should provide an overview of the research issue undertaken. In the future, it is planned to extend the study area to equal rural areas occurring in the world, and it is also planned to verify the existing hazards on the ground on a continuous basis. In addition, it is intended to extend the deeper cooperation with both the rural authorities and the rescue units in order to imply the research results in the actual territorial units.

Keywords: FMEA; Risk management; Rural areas; Crisis management; Humanitarian logistics
Rural Reg. Dev.
2023,
1
(2), 10007; 
Open Access

Article

11 October 2023

Fibrous SiC-based Mesoporous Solids for the Photocatalytic Degradation of Organic Pollutants under Artificial Light

SiC-based mesoporous solids with fibrous nanostructure were prepared by impregnation of a polycarbosilane precursor on annealed polyacrylonitrile (PAN) fibers and subsequent pyrolysis. The obtained material exhibits a mesoporous structure and has a specific surface area of ~20 m2/g. It has a semiconducting electronic character with a bandgap of 2.65 eV, i.e., in the visible range. Adsorption tests of methylene blue were performed on the material under dark conditions, which showed an adsorption amount of 78 wt%. The photocatalytic activity of the material was then evaluated for the degradation of the dye under artificial daylight irradiation over a period of 7 h. A degradation of 94 wt% was achieved. Regeneration and reuse of the material was also tested and resulted in 97 wt% degradation after reuse, indicating potential interest of the material as a contactor in environmental remediation devices.

Keywords: Silicon carbide; Preceramic polymers; Ceramics; Photocatalysis; Fibers
Photocatal. Res. Potential
2024,
1
(2), 10006; 
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