Cleaning Technique Research Articles

Spatiotemporal Utilization of Latent Heat in Erythritol‐based Phase Change Materials as Solar Thermal Fuels

AbstractSolar thermal fuels (STFs) have been particularly concerned as sustainable future energy due to their impressive ability to store solar energy in chemical bonds and controllably release thermal energy. However, currently studied STFs mainly focus on molecule‐based materials with high photochemical activity, toxicity, and compromised features, which greatly restricts their applications in practical scenarios of solar energy utilization. Herein, we present a novel erythritol‐based composite phase change material (PCM) as a new type of STFs with an outstanding capability to store solar energy as latent heat in its stable supercooling state and release thermal energy as needed. This composite PCM with stored thermal energy can be maintained stably at room temperature and subsequently release latent heat as high as 224.9 J/g during the crystallization process triggered by thermal stimuli. Remarkably, solar energy can be converted into latent heat stored in the composite PCM over months. Through mechanical stimulations, the released latent heat can increase the temperature of the composite up to 91 °C. This work presents a new concept of using spatiotemporal storage and release of latent heat in PCMs for solar energy utilization, making it a potential candidate as STFs for developing future clean energy techniques.

Spatiotemporal Utilization of Latent Heat in Erythritol-based Phase Change Materials as Solar Thermal Fuels.

Solar thermal fuels (STFs) have been particularly concerned as sustainable future energy due to their impressive ability to store solar energy in chemical bonds and controllably release thermal energy. However, currently studied STFs mainly focus on molecule-based materials with high photochemical activity, toxicity, and compromised features, which greatly restricts their applications in practical scenarios of solar energy utilization. Herein, we present a novel erythritol-based composite phase change material (PCM) as a new type of STFs with an outstanding capability to store solar energy as latent heat in its stable supercooling state and release thermal energy as needed. This composite PCM with stored thermal energy can be maintained stably at room temperature and subsequently release latent heat as high as 224.9 J/g during the crystallization process triggered by thermal stimuli. Remarkably, solar energy can be converted into latent heat stored in the composite PCM over months. Through mechanical stimulations, the released latent heat can increase the temperature of the composite up to 91 °C. This work presents a new concept of using spatiotemporal storage and release of latent heat in PCMs for solar energy utilization, making it a potential candidate as STFs for developing future clean energy techniques.

Applicability of the Barcelona scale to assess the quality of cleanliness of mucosa at esophagogastroduodenoscopy

Background and objectivesThere are few scales with prospective validation for the assessment of the upper gastrointestinal mucosal cleanliness during an esophagogastroduodenoscopy (EGD). The aim of this study was to develop a valid and reproducible cleanliness scale for use during an EGD. MethodsWe developed a cleanliness scale (Barcelona scale) with a score (0–2 points) of five segments of the upper gastrointestinal tract with thorough cleaning techniques (esophagus, fundus, body, antrum, and duodenum). First, 125 photos (25 of each area) were assessed, and a score was assigned to each image by consensus among 7 experts endoscopists. Subsequently, 100 of the 125 images were selected and the inter- and intra-observer variability of 15 previously trained endoscopists was evaluated using the same images at two different times. ResultsIn total, 1500 assessments were performed. In 1336/1500 observations (89%) there was agreement with the consensus score, with a mean kappa value of 0.83 (0.45–0.96). In the second evaluation, in 1330/1500 observations (89%) there was agreement with the consensus score, with a mean kappa value of 0.82 (0.45–0.93). The intra-observer variability was 0.89 (0.76–0.99). ConclusionsThe Barcelona cleanliness scale is a valid measure and reproducible with minimal training. Its application in clinical practice is a significant step to standardize the quality of the EGD.

Reviewing the potential of anaerobic membrane bioreactors in wastewater treatment

Anaerobic membrane bioreactors (AnMBRs) represent an innovative approach to wastewater treatment, combining anaerobic digestion with membrane filtration to achieve efficient organic pollutant removal and resource recovery. This review critically examines the potential of AnMBRs in wastewater treatment, highlighting their principles, advantages, challenges, recent advancements, and future prospects. AnMBRs offer several advantages over traditional aerobic treatment methods, including higher organic loading rates, reduced energy requirements, and biogas production through methane generation. However, challenges such as membrane fouling, reactor complexity, and operational costs have limited their widespread adoption. Recent advancements in membrane materials, fouling mitigation strategies, and process optimization have improved AnMBR performance and feasibility. Novel membrane materials with enhanced fouling resistance and durability have been developed, while innovative cleaning techniques and operational protocols have been implemented to mitigate membrane fouling and prolong membrane lifespan. Process optimization strategies, including reactor design modifications and operational parameter adjustments, have enhanced treatment efficiency and reduced energy consumption in AnMBRs. Future research directions in AnMBR technology focus on optimizing reactor configurations, exploring novel membrane materials and fouling control strategies, and conducting comprehensive techno-economic assessments to evaluate the environmental and economic sustainability of AnMBRs. Integration of AnMBRs with emerging technologies such as membrane distillation, forward osmosis, and bioelectrochemical systems holds promise for further enhancing treatment performance and resource recovery capabilities. Additionally, addressing knowledge gaps in membrane fouling mechanisms, microbial community dynamics, and long-term system stability is crucial for advancing AnMBR technology and facilitating its widespread implementation in wastewater treatment. Overall, AnMBRs offer significant potential for sustainable wastewater treatment, providing opportunities for organic pollutant removal, energy recovery, and resource reuse. By addressing technical challenges, optimizing process parameters, and conducting interdisciplinary research, AnMBRs can contribute to the development of efficient, cost-effective, and environmentally friendly wastewater treatment solutions, ultimately supporting the goal of achieving cleaner water resources and a more sustainable future.

Biofloc supplementation improves growth performances, nutrient utilization, and histological status of Nile tilapia (Oreochromis niloticus) while enhancing zooplankton diversity, community, and abundance

The present work investigates the effect of biofloc supplementation, as an environmentally clean aqua-feed technique, on water quality, growth performance, feed utilization, and histological status of Nile tilapia (Oreochromis niloticus). Moreover, indicators of zooplankton diversity, community structure, abundance, similarities, and cluster analysis were studied during the experiment. A 60-day growth experiment based on biofloc supplementation was performed to evaluate, in addition to the control group (BF0), the effects of five groups of biofloc supplementation (BF1 = 14.20, BF2 = 28.40, BF3 = 42.60, BF4 = 56.80, and BF5 = 71.0 g L−1, respectively) on Nile tilapia juveniles (initial body weight: 13.30 ± 0.01 g fish−1). During the 15 days of acclimation, the juveniles in all groups were fed twice daily on the same control diet (a commercial diet containing 28% protein). Then, the juveniles were randomly distributed to 18 tanks (each 0.5 m3 with a stocking of 40 fish/tank). The feed rate was 3% of the total fish biomass, adjusted weekly. The water quality indicators were in the ideal range recommended for Nile tilapia culture. The results found that the highest weight gain, specific growth rate and survival rate, and the lowest feed conversion ratio of fish were reported in the BF5 group. Moreover, this group achieved the highest zooplankton abundance (20,706 Ind. L−1) compared to the control group (457 Ind. L−1). The results showed that sections of the muscles in the control group (BF0) revealed fibers arranged into bundles. Comparisons between the muscles in the control group (BF0) and the bioflocs groups (BF1–BF5) showed unclear differences. However, sections of the muscle group BF1 showed increased splitting of muscle fibers and the separation of individual muscle fibers into smaller units. The liver showed multiple pathological lesions in all experimental groups (BF0–BF5). Zooplankton diversity indicators and cluster analysis data also reported a significant difference between the control group (BF0) and the biofloc groups, especially the BF5 group. The present study concluded that the addition of biofloc (71 g L−1) to culture ponds significantly improves the growth, feed utilization, and survival rates of Nile tilapia while enhancing zooplankton diversity, community, and abundance.

Development of an effective cleaning technique and ancillary analytical method for estimation of residues of selected kinase inhibitors from stainless steel and glass surfaces by swab sampling

Importance of cleaning validation in the pharmaceutical industry cannot be overstated. It is essential for preventing cross-contamination, ensuring product quality & safety, and upholding regulatory standards. The present study involved development of an effective cleaning method for five selected kinase inhibitors binimetinib (BMT), selumetinib (SMT), brigatinib (BGT), capmatinib (CPT), and baricitinib (BRT). For checking the effectiveness of the developed cleaning technique, a sensitive and specific RP-HPLC based analytical method employing a diode array detector has been established to quantitate drug residue on glass and stainless steel surfaces. A reproducible swab sampling protocol utilizing TX714A Alpha swabs wetted with an extracting solvent has been developed to collect representative samples from both surfaces. Chromatographic separation of selected kinase inhibitors was achieved in gradient mode using an Agilent Zorbax eclipsed C18 column with acetonitrile and 10 mM ammonium formate as the mobile phase. The analytes were chromatographically separated in a 12 min run time. The mean swab recovery for each drug from glass and stainless steel surfaces exceeded 90%. Cleaning with IPA (70%) and acetone (70%) effectively removed residues for all five drugs. A solution comprising 10 mM SDS with 20% IPA demonstrated good efficacy in cleaning residues of BGT, BRT, and CPT, but exhibited lower efficacy for SMT and BMT.

Cross-linked polymer film on copper stubs as a reusable substrate enabling imaging and quantitative analyses of aluminosilicate particles

Access issues to potable waters around the planet is the motivation for research in desalination technologies. One class of materials that is a research focus for desalination membranes are zeolites that are comprised of silicon (Si), aluminum (Al), and oxygen, and have structures that include regular pores of varying sizes dependent on the type of zeolite. A motivation for this study was to enable characterization of non-conductive materials containing Si or Al (e.g., zeolites) using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) techniques. To avoid significant background signals directly overlapping with these samples, common sample supports and preparation protocols involving Al or Si were precluded. Cross-linked polymer coatings applied via spin coating onto polished copper (Cu) stubs are shown to be durable for reuse even with the use of aggressive cleaning techniques between samples. SEM and EDS analyses of Cu stubs were performed before and after applying the polymer coating, after drop-cast application of zeolite particles and after their subsequent removal by sonication-based techniques. The data from those trials confirmed there was no background signal from Si or Al and no cross-contamination between samples during these analyses, enabling quantitation of Al and Si in the samples.

Effects of laser cleaning on the condition of different silk model samples using varying wavelengths and pulse durations

The cleaning of aged silk fibers poses a common challenge in the conservation of textiles, since traditional cleaning techniques often yield unsatisfactory results or even harm objects. In this regard, cleaning objects with laser radiation is a promising addition to the range of available methods. Due to it being contactless, even brittle and touch-sensitive objects with disfiguring or harmful soiling could potentially be cleaned and therefore made accessible for research and presentation. Examples of treatment have sometimes shown spectacular results. Still there is some skepticism concerning the safety of this treatment for textile materials, which has been strengthened through previous 532 nm wavelength nanosecond laser cleaning studies on silk fibers. Taking these published results into account, the range of examined laser parameters has been extended in this study, from 532 nm nanosecond laser to 1064 nm nanosecond and even 800 nm femtosecond laser, reevaluating the effect of this treatment on the fibers. The physicochemical processes taking place on the silk fibers when cleaning with lasers are complex and still not fully understood. The aim of this project was therefore to bring more clarification about potential effects of those processes on the condition of silk samples treated with a set of different parameters for wavelength, pulse duration, energy density and number of pulses per spot. It also looks at the influence of the presence of soiling on the results. The analysis of potential effects was then carried out using statistical methods and advanced analytics. Scanning electron microscopy, Fourier-transform infrared spectroscopy and colorimetry technology provided the required insights to better assess the effects. Results show that laser cleaning of silk fibers, like most other conventional cleaning techniques, is not completely without risk, but knowing what the possible effects are helps making decisions on whether the benefits of the technique used justify these risks.

Case Study Protocol to Evaluate the Impact of Training Intervention on Cleaners' Knowledge Level, Perceptions and Practices regarding Correct Cleaning Techniques at Selected Care Facilities in Limpopo Province, South Africa.

Despite being preventable, healthcare-associated infections are known primary causes of patient mortality and morbidity, threatening global public health. Though it is believed that one competent and dedicated cleaning staff member given the right tools and enough time can prevent more health-care-associated infectious diseases than a room full of doctors and nurses can cure, it was discovered in Letaba Hospital of the Limpopo Province, South Africa, that knowledge and practices of infection control among cleaning staff were not optimal. The proposed study aims to evaluate the impact of training interventions on cleaners' knowledge levels and practices. In Phase 1, cleaners' pre-training knowledge level, practices, and perceptions regarding correct cleaning techniques will be assessed through qualitative, individual, in-depth interviews. The initial question will read, "Describe the steps you follow when cleaning at this health facility and why?" In Phase 2a, a cleaning training program will be developed based on the South African Qualification Authority ID 118730 Healthcare Cleaner: Occupational Certificate Curriculum and the Center for Diseases Control and ICAN's Best Practices for Environmental Cleaning in Healthcare Facilities in Resource-Limited Settings. In Phase 2b, a cleaning training intervention will be implemented. In Phase 3, cleaners' post-training knowledge level, practices, and perceptions will be reassessed and compared to pre-training findings. The Standard Protocol Items: Recommendations for an Interventional Trial, commonly known as SPIRIT, guided the development of this protocol. This protocol received ethical clearance number FHS/22/PH/04/3005 in August 2023 from the University of Venda Human and Clinical Trials Research Ethics Committee. The protocol approval was granted by the Limpopo Provincial Department of Health (LP_2022-05-028) in October 2023. This protocol is registered with the South African National Clinical Trial Registry. The findings of this study may provide baseline data upon which healthcare facilities' cleaner training qualification curriculum may be developed. In addition, this protocol contributes to the application of qualitative methodology in an intervention trial.

Influence of the inner diameter of the bottom plate on the cleaning performance of double-layer filter cartridges

Dust collectors are used in various industries to separate pollutants from the air. Filter cartridge dust collectors are favored for their stability and small footprint. However, conventional cleaning techniques make it difficult to solve the problem of incomplete cleaning of filter cartridges, which require frequent replacement. Inner cone double-layer filter cartridges are utilized to improve the incomplete cleaning of filter cartridges. The size of the inner diameter (ID) of the bottom plate is one of the main factors affecting the cleaning performance of the double-layer filter cartridge. Double-layer filter cartridges' inside flow field is investigated by numerical simulation in this work. Selection of evaluation indexes such as peak static pressure and comprehensive pressure to assess cleaning performance and analyze the effect of ID on cleaning performance. It was shown that increasing ID could optimize the upper section of the filter cartridges' static pressure distribution. Both larger (ID = 160 mm) and smaller (ID = 40 mm) filter cartridges ID possessed better bottom static pressure accumulation capacity. As the inner diameter of the bottom plate decreases, the cleaning performance increases and then decreases, and the best results were obtained at an ID of 140 mm, with a PC of 1175 Pa. Notably, IDs exceeding 160 mm have a significant negative impact on the cleaning performance of the filter cartridges.

Comparative Evaluation of Supplementary Cleaning Techniques for Removal of Bio-C Sealer and AH-Plus from Oval Root Canals: A Micro-CT Analysis.

This study aimed to compare the effectiveness of two endodontic cleaning techniques, passive ultrasonic irrigation (PUI) and the XP-endo Finisher R (XPR) system, in removing residual filling material during endodontic retreatment procedures. Forty mandibular premolars with oval canals were divided into four groups based on the sealer used (AH-Plus or Bio-C Sealer) and the cleaning technique employed (PUI or XPR). To ensure uniformity of canal volume among groups, initial micro-CT scans were conducted. The canals were instrumented, filled, and then re-instrumented before undergoing either PUI or XPR cleaning techniques. Residual filling material volumes were assessed through micro-CT scans, and statistical analysis was performed using the Kruskal-Wallis and Mann-Whitney U tests. Following instrumentation, there was no significant difference in residual filling material volumes between AH-Plus and Bio-C Sealer groups (1.35 mm3and 1.02 mm3, respectively; P>0.05). However, after supplementary cleaning techniques, XPR-cleaned specimens exhibited significantly less residual material compared to PUI-cleaned specimens (0.01 mm3 and 0.29 mm3 for Bio-C Sealer, and 0.07 mm3 and. 0.30 mm3for AH-Plus, P<0.05). The XPR system was found to be more effective than PUI in removing residual filling material from Bio-C Sealer-filled root canals. This highlights its potential as a useful supplementary cleaning technique in endodontic retreatment procedures.

GLO GERM AND COVID-19: ILLUMINATING HYGIENE AND PROMOTING TRANSMISSION AWARENESS.

Maintaining effective surface hygiene and preventing contamination is of paramount importance. Our study introduces Glo Germ, a versatile product available in various forms, which possesses the unique ability to reveal hidden truths under ultraviolet light, enhance understanding of hygiene, and spread awareness of COVID-19 transmission and preventive measures. A comprehensive study was conducted to assess different surface cleaning techniques' effectiveness. Glo Germ, containing a fluorescent dye activated by ultraviolet light, was used to visualize germ spread and compare disinfectant cleaners' efficacy. The study encompassed diverse surfaces and materials, aiming to identify optimal cleaning techniques for each context. Furthermore, a small illustrative study was conducted during a COVID-19 awareness presentation involving students. Glo Germ was applied to hands, revealing its subsequent spread to faces and surfaces. This visual experiment effectively emphasized hand hygiene and mask-wearing importance. Results indicated that while water alone achieved satisfactory cleaning results, using detergent and the appropriate cleaning tools further improved efficacy. Notably, adhering to consistent patterns and applying pressure during cleaning proved essential. The student demonstration showed how contaminants spread quickly, highlighting hand hygiene's significance and the potential extent of contamination through sneezing. Glo Germ inclusion in these experiments highlights its potential in educating about surface cleaning and microbial transmission, offering an interactive and engaging approach to promoting personal hygiene and fostering illness prevention awareness.

Use of hyperspectral imaging to monitor the effectiveness of plasma-generated atomic oxygen for non-contact cleaning of indigo dyed silk

This study explores the use of hyperspectral imaging (HSI) to monitor the effectiveness of plasma-generated atomic oxygen (AO) treatment for non-invasive cleaning of cultural heritage object. Silk samples dyed with indigo blue, including those soiled with soot to mimic historical artifacts, were treated with plasma-generated atomic oxygen for varying durations. Using HSI with a TWINS [1,2] birefringent interferometer, diffuse reflectance and light-induced fluorescence are observed. That allowed a precise evaluation of sample degradation avoiding any invasive sample extraction. This research not only contributes to the field of cultural heritage conservation but also enhances understanding of indigo colour degradation processes and the evaluation of non-invasive cleaning techniques on sensitive materials.

Electrochemical measurement of ruthenium oxide quantum dots synthesized at room temperature

Electrochemical energy storage has evolved into one of the most significant areas of current research to meet the escalating energy demands of contemporary society. Apart from the depletion of conventional sources of energy, the emission of hazardous chemicals is dangerous to the environment and human health as well. Among various electrochemical energy storage systems, the supercapacitor is emerging rapidly because of its elevated lifetime, flexibility, and light weight in various industrial areas. Ruthenium oxide (RuO2) is one of the most promising nanomaterials, with several applications in catalysts, sensors, microelectronics and other fields. Among numerous applications, ruthenium oxide is considered a promising candidate for electrode material for supercapacitors owing to its fast redox kinetics, low resistivity and high thermal and mechanical stabilities. Nowadays, researchers are increasingly turning to the biosynthesis of nanoparticles in order to establish clean, economical, and efficient synthesis techniques. In the present report, we have mycologically synthesised RuO2 quantum dots (RuO2 QDs), and different characterization techniques have been employed for the conformational nature of the quantum dots. Further, electrochemical studies have investigated the electrochemical potential of the mycologically synthesised RuO2 QDs utilising cyclic voltammetric measurements. The specific capacitance of RuO2 QDs coated on carbon cloth electrodes was 230 Fg−1 at a scan rate of 5.0 Ag−1 and the capacitance retention was found to be 95.8 % at the end of the 1000th charge-discharge cycle. The working electrodes derived from RuO2 QDs has rendered corrosion resistance in H2SO4 up to 0.16 M. A working model is also put to the test to find out the feasibility of QDs in practical application.

Phase Transition Engineering of Vanadium Dioxide Induced by Oxygen Vacancies

A reconfigurable optical functional system is a pioneering and comprehensive approach for portable future flexible electronics, irrespective of traditional silicon-based technology. VO2 shows tremendous temperature-dependent structural and electrical phase transitions as a complex correlated metal oxide, presenting it as a potential candidate for bolometers, thermal camouflage, and optoelectronics applications. However, the structural stability and high transition temperature restrict room-temperature applications. The present study reports the oxygen vacancies-assisted phase transition engineering in the VO2/muscovite heterostructure. The ion bombardment alters the oxygen stoichiometry of VO2/muscovite thin film at room temperature. A significant decrease in lattice constant has been observed during the transition of the insulating M1 (monoclinic) phase into the metallic R (tetragonal) phase, which was confirmed through high-resolution XRD. The change in oxygen vacancy concentration determined using X-ray photoelectron spectroscopy (XPS) actively suppressed and stabilized the epitaxial thin film of VO2 near room temperature. We investigated whether applying increasing power-mediated ion bombardment for a few minutes affects the oxygen vacancy formation on the VO2/muscovite film’s surface. Consequently, a change in KPFM and 4 orders of magnitude change in resistance of VO2 thin film have been observed. This report reveals the fundamental understanding of controlling the MIT in epitaxial VO2 thin film via facile and clean phase transition engineering techniques for advanced flexible electronic devices.

Assessment of Energy-Efficient Spouted Bed Aerobic Composting Performance for Municipal Solid Waste: Experimental Study

Municipal solid waste contains a high percentage of organic waste, and when it is not disposed of, it becomes a threat to the environment by contaminating the air, water, and soil. Composting is one of the recovery techniques in which the end product of waste eventually contributes to the agriculture industry, reducing the harmful effects on the environment. Composting municipal solid waste is a clean and effective technique for waste disposal. The mechanized composting process is carried out by several methods, like the windrow method or the rotary drum method. However, large-scale composting processes involve energy consumption and labor costs for waste preparation and handling. This increases the market cost of compost. Hence, an energy-efficient composting technique with minimum environmental impact is needed. This research work aims to analyze the performance of an energy-efficient spouted bed technique for aerobic composting of municipal solid waste for the first time using spouted bed technology with sand as the bed material. Spouted bed composting handles the waste using a pneumatic method with minimum power consumption in comparison to conventional mechanical methods with windrow processes or rotary composting machines. The experimental procedure involves a test run of waste along with bed material and the collection of temperature variations, pH variations, moisture variations, and volatile matter content during the progression of the composting process. The results of this experimental study on a single batch of waste are then used to analyze the quality of the compost generated and compare it with existing results. Specific energy consumption for the process was less than 800 kJ/ton of raw waste input, which is much less than the energy used for conventional composting techniques. pH, volatile content, moisture, and temperature measurements indicated agreement with the established parameters of the composting process.

Enhanced stability and electrochemical investigations of Ni/ZSM-5 catalyst layer on nickel-based anodes for ammonia-fed solid oxide fuel cells

Ammonia-fed solid oxide fuel cell (SOFC) is a promising clean energy technique with distinctive advantages of zero-carbon emission, easy storage, and high efficiency. However, the typical nickel anode for SOFC is susceptible to structural change and performance degradation under an ammonia environment, particularly at reduced operating temperatures. In addition, obtaining a deep understanding of the individual electrode processes is demanded for the rational design and optimization of NH3–SOFCs. This work enhances the cell performance and durability of ammonia-fed SOFCs by utilizing a cost-effective ammonia decomposition catalyst (Ni/Na-ZSM). The electrode processes are investigated quantitively using distributed relaxation time (DRT) and equivalent circuit model (ECM) analysis. Accelerated degradation tests are conducted for the NH3-based SOFC cells by thermal cycling at operational temperatures of 700 °C-650 °C. Compared to the conventional cell, the cell with the Ni/Na-ZSM catalyst exhibits improved cell performance and five times less decay. In situ measurements and impedance analysis combined with microstructural characterization reveal that the durability enhancement is probably ascribed to protecting the structure of the three-phase boundaries (TPBs), which maintains a stable resistance of the TPB charge transfer processes during the temperature cycling.

A Review on Solar Panel Cleaning Systems and Techniques

This paper provides an overview of the cleaning aspects of solar panels through a literature review. We first discuss the drawbacks of unwanted deposits on solar panels in terms of energy production and efficiency. Existing cleaning practices and technologies are then presented with an emphasis on factors such as the size of the facility, location, cost, and available resources. Finally, a comparative cost–benefit analysis is carried out using decision support tools and taking into account different relevant criteria to support users choose the right cleaning maintenance for their specific solar installation.

Aerovalved Pulse Combustor for Enhancing Efficiency and Sustainability of Fossil Energy Conversion

Abstract The paper actualizes earlier research in developing a pulse combustion technique for enhancing the efficacy of utility and industrial boilers and furnaces. Some unpublished results of the experimental investigation of self-sustained pulsating combustion of a gas fuel in an aerovalved pulse combustor (PC) are presented. Relationships have been established between all important design and operating parameters and the combustion characteristics. It was demonstrated that a well-designed pulse combustor can operate efficiently in a stable self-pumping regime in a wide range of operating conditions with the loading from 20% to 100% of the maximum power. While a PC can operate autonomously as a gas burner, the present focus is on their use for mitigating slug and ash deposits on heating surfaces of coal- or biomass fired power and industrial boilers, thus providing an alternative to the proven detonation pulse (DPC) or other techniques for on-line cleaning of heating surfaces during the operation of power and industrial boilers.

Android Malware Classification Based on Fuzzy Hashing Visualization

The proliferation of Android-based devices has brought about an unprecedented surge in mobile application usage, making the Android ecosystem a prime target for cybercriminals. In this paper, a new method for Android malware classification is proposed. The method implements a convolutional neural network for malware classification using images. The research presents a novel approach to transforming the Android Application Package (APK) into a grayscale image. The image creation utilizes natural language processing techniques for text cleaning, extraction, and fuzzy hashing to represent the decompiled code from the APK in a set of hashes after preprocessing, where the image is composed of n fuzzy hashes that represent an APK. The method was tested on an Android malware dataset with 15,493 samples of five malware types. The proposed method showed an increase in accuracy compared to others in the literature, achieving up to 98.24% in the classification task.