Conventional Cleaning Methods Research Articles

Unlocking the potential of lactic acid bacteria mature biofilm extracts as antibiofilm agents

The continuous growth of biofilm infections and their resilience to conventional cleaning methods and antimicrobial agents pose a worldwide challenge across diverse sectors. This persistent medical, industrial, and environmental issue contributes to treatment challenges and chronic diseases. Lactic acid bacteria have garnered global attention for their substantial antimicrobial effects against pathogens and established beneficial roles. Notably, their biofilms are also predicted to show a promising control strategy against pathogenic biofilm formation. The prevalence of biofilm-related problems underscores the need for extensive research and innovative solutions to tackle this global challenge. This novel study investigates the effect of different extracts (external, internal, and mixed extracts) obtained from Lactobacillus rhamnosus GG biofilm on pathogenic-formed biofilms. Subsequently, external extracts presented an important eradication effectiveness. Furthermore, a 6-fold concentration of these extracts led to eradication percentages of 57%, 67%, and 76% for Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa biofilms, respectively, and around 99.9% bactericidal effect of biofilm cells was observed for the three strains. The results of this research could mark a significant breakthrough in the field of anti-biofilm and antimicrobial strategies. Further studies and molecular research will be necessary to detect the molecules secreted by the biofilm, and their mechanisms of action engaged in new anti-biofilm strategies.

Ultraclean Suspended Graphene by Radiolysis of Adsorbed Water.

Access to intrinsic properties of a 2D material is challenging due to the absence of a bulk that would dominate over surface contamination, and this lack of bulk also precludes effective conventional cleaning methods that are almost always sacrificial. Suspended graphene and carbon contaminants represent the most salient challenge. This work has achieved ultraclean graphene, attested by electron energy loss (EEL) spectra unprecedentedly exhibiting fine-structure features expected from bonding and band structure. In the cleaning process in a transmission electron microscope, radicals generated by radiolysis of intentionally adsorbed water remove organic contaminants, which would otherwise be feedstock of the notorious electron irradiation induced carbon deposition. This method can be readily adapted to other experimental settings and other materials to enable previously inhibited undertakings that rely on the intrinsic properties or ultimate thinness of 2D materials. Importantly, the method is surprisingly simple and robust, easily implementable with common lab equipment.

Solar Based Floor Cleaning Robot Using IOT

This project introduces a new type of robot, Solar-Powered Autonomous Floor Cleaning Robot in response to the increasing demand of sustainable and energy-efficient solutions in robotics. The robot is designed to move on its own indoors, outdoors and clean different types of floors while getting power from solar panels that are integrated into its body. By using this method, it tries to reduce the impact on the environment that comes with conventional cleaning methods as well as increase the efficiency of floor maintenance generally.The primary objective of the proposed robot is to address the challenge of maintaining optimal efficiency in solar energy harvesting by ensuring the cleanliness of solar panels in industrial environments. The robot incorporates autonomous navigation and cleaning capabilities, employing advanced sensors and artificial intelligence algorithms to detect and navigate around obstacles while efficiently cleaning the solar panel surfaces.The robot's design emphasizes modularity and scalability, allowing it to adapt to diverse industrial environments and solar panel configurations. Equipped with cleaning brushes and a water-efficient system, the robot ensures thorough cleaning without causing damage to the solar panels. Additionally, the integration of real-time monitoring capabilities enables remote tracking of cleaning operations and assessment of overall system performance.

Photothermal Assisted Interfacial Cleaning with Semiconductor‐Based Sorbents: Recent Advances and Future Outlook for Effective Oil Spill Remediation

AbstractOceanic oil spills exert enduring adverse effects on marine ecosystems and human health. In contrast to conventional cleaning methods, advanced oil sorbents present a promising technology characterized by low cost, reduced environmental impact, and exceptional hydrophobicity and oleophilic properties for efficient oil removal from seawater. Despite these advantages, the efficacy of sorbents is hindered by highly viscous oil, impeding the oil/water separation process. To overcome this limitation, solar‐driven sorbents incorporating semiconductor materials are innovatively developed, leveraging increased temperatures to enhance crude oil absorption by reducing viscosity. Herein, a comprehensive review specifically focuses on various semiconductor‐functionalized sorbents for oil spill remediation, elucidating oil weathering and traditional cleaning methods to underscore the complexities and challenges in oil cleaning processes. An in‐depth discussion about the cleaning mechanisms of sorbents and the photothermal conversion processes facilitated by semiconductors is also provided. Additionally, it explores three coupling strategies—Joule heating and solar heating, photothermal effect, and magnetic effect, as well as photothermal and photocatalysis—that offer significant advancements in oil cleanup efficiency. Concluding with forward‐looking insights, the challenges and perspectives for the next generation of ocean oil spill removal technologies are proposed at the end.

Design and Development of a Solar-Powered Vacuum and Wet Cleaning Robot using Arduino UNO

n today’s day and time, it is difficult to find the time to clean our homes by ourselves. It is even more difficult to do so with conventional cleaning methods. This is where vacuum cleaners come to our aid to provide an efficient way to keep our surroundings clean, with the help of motors and filters that can pull up any kind of dirt and dust. In this paper, we present the design and implementation of a dual-function cleaning robot, which functions both as a vacuum cleaner and a wet floor cleaner. The robot is powered by a solar panel and is equipped with an Arduino UNO, a motor driver shield, and DC motors. An ultrasonic sensor was also integrated for obstacle detection. The vacuum function employs suction to remove dust and debris from floors, while the wet floor cleaning function uses wipers and a small pump to dispense water and clean the surface. This paper outlines the components, design considerations, and testing results for this innovative and eco-friendly cleaning solution.

Electrostatic cleaning effect on the performance of PV modules in Jordan

This study investigates the effect of dust accumulation on photovoltaic modules performance and proposes a new photovoltaic cleaning method based on static electricity concepts. The results of the proposed cleaning method were compared with the results of three different conventional photovoltaic cleaning methods: manually -the reference-, naturally, and nano-coating. The economic feasibility of the proposed cleaning method was compared with the nan-coating cleaning method. For the mentioned purpose, a system of four photovoltaic modules was installed in Amman, the system was exposed to natural dust. Energy loss due to dust accumulation after two weeks of exposure to natural dust without cleaning or rain was found to be 5.93% for the naturally cleaned module. Electrostatic neutralization cleaning reduced energy loss to 4.56%. Nano-coating reduced energy loss to 2.33%. According to the literature on cleaning of PV modules, the average power loss of photovoltaic modules due to dust accumulation is extreme which could reach 1% per day. 1.37% enhancement in energy saving utilizing electrostatic neutralization cleaning is a highly appreciated improvement in the photovoltaic module's efficiency. From an economic perspective, nano-coating was about 3.8 times cheaper compared with electrostatic neutralization under the stated conditions in this study. Electrostatic neutralization has a promising techno-economic future for mega solar power plants in arid regions compared with nano-coating by developing a robust practical mechanism with less capital and running costs owing to nano-recoating barriers.

CaO2-based tablet for effective and green membrane cleaning without additional catalysts

Natural organic matter humic acid (HA) coupled with the inorganic metal oxides FeOx + MnOx will cause severe irreversible membrane fouling. Chemical cleaning is indispensable for the removal of irreversible membrane foulants and sustainable membrane filtration, while conventional cleaning methods have limitations with low cleaning efficiency, high reagents consumption and potential membrane damage. For the first time, calcium peroxide (CaO2), a solid alternative for liquid hydrogen peroxide (H2O2), is proposed for the membrane cleaning. For membranes fouled by HA, it is noteworthy that 40 mg/32.15 cm2 CaO2 tablet without any other catalyst can restore the terminal membrane flux dramatically from 51% to 82% in only 5 min, which is far more than 3 wt% H2O2 alone (only from 51% to 59%). Moreover, Fenton-like reaction induced by in-situ membrane foulants FeOx + MnOx further enhances the membrane flux from 53% to 97%. Based on HA oxidation tests and reactive species identification in CaO2 tablets cleaning process for the case of HA-fouled membranes and HA + FeOx + MnOx-fouled membranes, singlet oxygen (O21) in CaO2 system dominated the strong oxidation of electron-rich compounds HA, which plays a key role in membrane flux recovery. With involvement of FeOx + MnOx, signal intensities of free radicals such as hydroxyl radicals (OH•) are enhanced greatly, which further achieves more outstanding membrane cleaning performance. These results underline that the novel CaO2 system provides a promising candidate for more portable and cost-effective membrane cleaning method in a nonradical pathway.

Effect of ultrasound assisted cleaning on pesticide removal and quality characteristics of Vitis vinifera leaves.

In this study, the pesticide (acetamiprid, deltamethrin, and pyridaben) removal and physicochemical quality improvement of vine (Vitis vinifera) leaf were examined using ultrasonic and traditional cleaning for 5, 10, and 15min. After an ultrasonic cleaning procedure at 37kHz for 10min, acetamiprid, deltamethrin, and pyridaben in vine leaf were reduced by 54.76, 58.22, and 54.55%, respectively. Furthermore, the total phenolic content (TPC) in vine leaf increased to 13.45mg GAE/g DW compared to that in control samples using traditional cleaning (10.37mg GAE/g DW), but there were no significant differences in DPPH radical scavenging activity. After 15min of conventional cleaning, the total chlorophyll and total carotenoid content of leaves were found to be lowest among all samples, at 6.52mg/kg and 0.48mg/kg, respectively. In conclusion, when compared to conventional cleaning methods, ultrasonic cleaning with no chemicals or heat treatment has proven to be a successful and environmentally friendly application in reducing commonly used pesticides and improving the physicochemical qualities of leaves.

Novel sodium percarbonate-MnO2 effervescent tablets for efficient and moderate membrane cleaning

Membrane flux recovery efficiency and durability are two key factors closely associated with the practical application for membrane cleaning process. However, conventional chemical membrane cleaning method by soaking the whole membrane module in highly concentrated chemical reagents has prominent drawbacks including the low mass transfer efficiency of reagents, long period of washing time, and the potential threat to membrane structure. Herein, for the first time, we report a facile approach to fabricate the sodium percarbonate-MnO2 effervescent tablets which show bubbling reaction to release oxygen and free radicals when being dispersed in water for membrane cleaning. Due to the synergistic effect of MnO2 and sodium percarbonate, the tablets are highly effective to clean the membrane fouled by humic acid within 5 min, with the terminal membrane flux being recovered from 0.50 to 0.95, and the irreversible fouling resistance being reduced by more than 90%, which is prominently more efficient than the conventional chemical cleaning methods. Moreover, even by consecutive membrane fouling and cleaning for 6 times, the membrane flux and filtration efficiency of the membrane could still be kept almost constant, and the moderateness of this membrane cleaning method was also verified by the systematic microscopic analysis. For mechanism study, results of Electron Spin Resonance (ESR) and quenching experiments indicated that the high-efficiency and robust durability of sodium percarbonate-MnO2 (SPC-MnO2) system for membrane cleaning was mainly attributed to the abundantly generated hydroxyl radicals and secondary free radicals (i.e. carbonate radicals). Conclusively, compared with the conventional membrane cleaning method with liquid cleaning reagents, the novel SPC-MnO2 system with remarkable advantages in terms of convenience and membrane cleaning performance demonstrated high potential for the wide application in practice.

Laser-assisted removal of weld heat tints from stainless steel surface

The heat generated during the welding of stainless steel results in the oxidation of the surface that, apart from aesthetics, adversely affects its corrosion property too. This communication reports the successful removal of heat tint generated by the gas tungsten arc welding process off a stainless steel surface in addition to an improvement in its pitting corrosion resistance by exposure to the emission of a nanosecond pulsed fiber laser. The laser cleaning experiments, conducted with six different laser pulses having different temporal shapes and duration that varied from 20 to 1020 ns, revealed that removal of the weld heat tint was possible in all conditions provided the effective laser fluence exceeded a definite threshold value. This threshold value, in turn, was found to increase with an increase in pulse duration. The laser cleaned specimens were subsequently analyzed for surface morphology, roughness, and pitting corrosion resistance. The pitting corrosion resistance of the laser-treated specimens was compared with the as-welded specimens and welded specimens with heat tint removed using conventional methods like wire brush cleaning and chemical pickling. The superior quality of tint removal, improved pitting corrosion resistance, and the ease of noncontact operation indicates the significant potential of the fiber laser-based weld tint removal method to substitute the conventional mechanical or chemical cleaning methods currently in use in the manufacturing industry.

Glass Substrate Dust Removal Using 233 fs Laser-Generated Shockwave.

Eliminating dust is gaining importance as a critical requirement in the display panel manufacturing process. The pixel resolution of display panels is increasing rapidly, which means that even small dust particles on the order of a few micrometers can affect them. Conventional surface cleaning methods such as ultrasonic cleaning (USC), CO2 cleaning, and wet cleaning may not be sufficiently efficient, economical, or environment friendly. In this study, a laser shockwave cleaning (LSC) method with a 233 fs pulsed laser was developed, which is different from the laser ablation cleaning method. To minimize thermal damage to the glass substrate, the effect of the number of pulses and the gap distance between the focused laser beam and the glass substrate were studied. The optimum number of pulses and gap distance to prevent damage to the glass substrate was inferred as 500 and 20 μm, respectively. With the optimal pulse number and gap distance, cleaning efficiency was tested at a 95% removal ratio regardless of the density of the particles. The effective cleaning area was measured using the removal ratio map and compared with the theoretical value.

Adaptive Floor Cleaning Strategy by Human Density Surveillance Mapping with a Reconfigurable Multi-Purpose Service Robot.

Professional cleaning and safe social distance monitoring are often considered as demanding, time-consuming, repetitive, and labor-intensive tasks with the risk of getting exposed to the virus. Safe social distance monitoring and cleaning are emerging problems solved through robotics solutions. This research aims to develop a safe social distance surveillance system on an intra-reconfigurable robot with a multi-robot cleaning system for large population environments, like office buildings, hospitals, or shopping malls. We propose an adaptive multi-robot cleaning strategy based on zig-zag-based coverage path planning that works in synergy with the human interaction heat map generated by safe social distance monitoring systems. We further validate the proposed adaptive velocity model’s efficiency for the multi-robot cleaning systems regarding time consumption and energy saved. The proposed method using sigmoid-based non-linear function has shown superior performance with 14.1 percent faster and energy consumption of 11.8 percent less than conventional cleaning methods.

Scalable Particle Removal for sub-5 nm Nodes

Wet cleaning has become challenging as the feature size of semiconductor devices decreased to sub-5 nm nodes. One of the key challenges is removing various types and sizes of particles and contamination from complex and fragile 3D structures without pattern damage and film loss. Conventional physical cleaning methods, such as dual-fluid spray or megasonic cleaning, are being used for the particle removal process. However, in advanced device nodes, these methods induce pattern damage and film loss. In this paper, we describe a novel particle removal technology called Nanolift which uses a polymer film consisting of two organic resins with different functions and achieved high particle removal efficiency on various types and sizes of particles with no pattern damage and minimum film loss.

Lubricant-infused directly engraved nano-microstructures for mechanically durable endoscope lens with anti-biofouling and anti-fogging properties

While a clear operating field during endoscopy is essential for accurate diagnosis and effective surgery, fogging or biofouling of the lens can cause loss of visibility during these procedures. Conventional cleaning methods such as the use of an irrigation unit, anti-fogging surfactant, or particle-based porous coatings infused with lubricants have been used but proven insufficient to prevent loss of visibility. Herein, a mechanically robust anti-fogging and anti-biofouling endoscope lens was developed by forming a lubricant-infused directly engraved nano-/micro-structured surface (LIDENS) on the lens. This structure was directly engraved onto the lens via line-by-line ablation with a femtosecond laser. This directly engraved nano/microstructure provides LIDENS lenses with superior mechanical robustness compared to lenses with conventional particle-based coatings, enabling the maintenance of clear visibility throughout typical procedures. The LIDENS lens was chemically modified with a fluorinated self-assembled monolayer (F-SAM) followed by infusion of medical-grade perfluorocarbon lubricants. This provides the lens with high transparency (> 70%) along with superior and long-lasting repellency towards various liquids. This excellent liquid repellency was also shown to be maintained during blood dipping, spraying, and droplet condensation experiments. We believe that endoscopic lenses with the LIDENS offer excellent benefits to endoscopic surgery by securing clear visibility for stable operation.

Effect of different laser energy densities on the corrosion resistance of aluminum alloys

Purpose Laser cleaning, as a new type of cleaning technology, has the advantages of environment-friendliness, better selectivity, better controllability and higher efficiency compared to traditional chemical cleaning or grinding. This paper aims to use ultra-fast surface laser cleaning equipment built in laboratory to study the influence of different energy density (7.6, 11.5 and 15.3 J/cm2) on corrosion resistance of the aluminum alloy A7N01P-T4, a high-speed train body material. Design/methodology/approach SEM, white light interferometer, EDS and XPS were used to analyze the surface morphology, roughness, element content and oxide layer composition of aluminum alloy before and after cleaning. The corrosion resistance was studied by electrochemical experiments and exfoliation corrosion experiments. Findings The results showed that new oxide scale was formed on the surface after laser cleaning. The changes of surface roughness and chemical composition of oxide scale made a significant influence on corrosion behaviors. Better corrosion resistance was obtained with the energy density increased, and at the energy density of 11.5 J/cm2, aluminum alloy exhibited the best corrosion resistance. Research limitations/implications The paper only studies specific aluminum alloys and is not universal. Laser cleaning equipment is set up for the laboratory and has not yet been put into industrial production. Practical implications This paper indicated that ultra-fast laser processing was a new direction for the development of industrial equipment surface cleaning and carried out ultra-fast laser of aluminum alloy surface cleaning had certain research significance for its corrosion resistance. Social implications Compared with the conventional cleaning methods such as air abrasives grinding or chemical cleaning, laser cleaning has advantages of environment-friendliness, better selectivity, better controllability and higher efficiency. Laser cleaning can not only protect the environment, but also improve cleaning efficiency. Originality/value Changes in the surface of aluminum alloys after ultra-fast surface laser treatment were found, and the mechanism of changes in aluminum alloy corrosion properties was clarified.

Smart Street Litter Detection and Classification Based on Faster R-CNN and Edge Computing

Cleanliness of city streets has an important impact on city environment and public health. Conventional street cleaning methods involve street sweepers going to many spots and manually confirming if the street needs to be clean. However, this method takes a substantial amount of manual operations for detection and assessment of street’s cleanliness which leads to a high cost for cities. Using pervasive mobile devices and AI technology, it is now possible to develop smart edge-based service system for monitoring and detecting the cleanliness of streets at scale. This paper explores an important aspect of cities — how to automatically analyze street imagery to understand the level of street litter. A vehicle (i.e. trash truck) equipped with smart edge station and cameras is used to collect and process street images in real time. A deep learning model is developed to detect, classify and analyze the diverse types of street litters such as tree branches, leaves, bottles and so on. In addition, two case studies are reported to show its strong potential and effectiveness in smart city systems.

Tradeoff Between Area Coverage and Energy Usage of a Self-Reconfigurable Floor Cleaning Robot Based on User Preference

Floor cleaning robots have been developed to cope with the issues arisen with conventional cleaning methods that involve extensive human labor. hTetro is a self-reconfigurable floor cleaning robot that has been introduced to improve area coverage. Polyomino tiling theory is utilized by hTetro to plan area coverage. Energy usage and area coverage are distinct for different tiling arrangements, and they are often conflicting entities. Therefore, hTetro needs to maintain the tradeoff between area coverage and energy usage to improve its performance. This paper proposes a novel method to determine the tradeoff between area coverage and energy usage of a tiling theory-based self-reconfigurable floor cleaning robot per user preference. A linguistic option such as “High coverage” that represents user preference has uncertainty since fuzzy linguistic terms do not possess definitive meaning. Moreover, the meaning of such user preference depends on the present status of the robot. Thereby, a novel fuzzy inference system is proposed to determine the tradeoff between area coverage and energy usage by interpreting the meaning of user preference while accounting for the present status of the robot. A Weighted Sum Model (WSM) based Multiple-criteria decision-making (MCDM) method is adapted per user preference interpreted by the fuzzy inference system. The behavior of the proposed system has been evaluated considering heterogeneous test cases. The behavior of the test cases confirms the applicability of the proposed concept for adapting the tradeoff between area coverage and energy usage of a self-reconfigurable floor cleaning robot based on user preference.

Removal of Contaminant Nanoparticles with $$\hbox {CO}_2$$ Nanobullets at Atmospheric Conditions

As the feature size of semiconductor chips is decreasing down to nanometric scales, cleaning of nanoscale contaminant particles without damaging the fine features puts forth severe technological challenges. Here we introduce a design methodology of a nozzle to generate a beam of supersonic $$\hbox {CO}_2$$ solid nanobullets into the air at atmospheric pressure, which dislodge the contaminant particles by colliding with them. The dry cleaning scheme proposed here does not resort to the chillers, vacuum chamber, and carrier-gas handling system, which conventional dry cleaning systems often required and thus hampered their practical applications. We provide a theoretical framework to select key design parameters, such as the area ratio of the nozzle throat and exit and the supply gas pressure. We experimentally verify the superior capability of our nozzle in generating a $$\hbox {CO}_2$$ aerosol beam under the atmospheric back pressure condition. Additional process parameters including the stand-off distance and the incident angle of the $$\hbox {CO}_2$$ beam are optimized to maximize the cleaning efficiency and minimize the pattern damages. Our work suggests a practical nanoparticle cleaning scheme that is faster and simpler than the conventional dry cleaning methods.

Membrane backwash cleaning using CO2 nucleation

Low pressure membranes, such as ultrafiltration (UF), are widely used in water treatment applications, including the pretreatment of reverse osmosis desalination. UF membranes produce a water of superior quality, in addition to reducing the footprint and the use of chemicals, compared to conventional methods. However, membrane fouling remains a major drawback, and frequent membrane cleanings are required to maintain the flux of water and its quality. Typically, after a series of backwashes using an UF permeate, a chemical cleaning process is applied to fully recover the membrane's permeability. However, frequent chemical cleanings negatively affect the lifetime of the membrane, the environment, and increase operational costs. Here, we introduce a novel cleaning method that uses a solution saturated with CO2 to clean the membranes through the backwash step. As the pressure drops, the CO2 solution becomes supersaturated, and bubbles start to nucleate within the membrane pores and on its surface, resulting in the effective removal of the deposited fouling material. These foulants are further helping the nucleation process as they are considered as imperfection sites with high creation and growth of bubbles. Investigations performed for different synthetic feed solutions of organic compounds (sodium alginate), colloidal matter (silica) and sea salts, at different concentrations, show that our new physical cleaning process using CO2 is more performant than the regular backwash using Milli-Q water. We obtain a 100% flux recovery, in a short time, even under severe irreversible fouling conditions. Based on these results, we conclude that replacing water by a solution saturated with CO2 for the backwash cleaning of filtration membranes provides significant benefits to existing cleaning processes, and represent a promising alternative for improving and lowering the frequency of conventional chemical cleaning methods.

Termografija u kontroli efikasnosti i bezbednosti laserskog čišćenja

Innovative laser cleaning technology for various surfaces in the industry, includes an integrated approach to controlling the process of laser-material interaction and testing laser treatment results. Laser cleaning has significant advantages over conventional cleaning methods: it has high selectivity, precision, efficiency and reliability in an application for different types of materials. The thermal nature of the laser cleaning process brings a certain risk for cleaning objects, and the process optimization research is in the focus of interest of a large number of scientists. This paper presents the results of laser paint, on the copper surface, and the protective layer, on the printed circuit board, cleaning. The control of the real-time laser cleaning process was carried out using an infrared camera. The micromorphological characteristics of the cleaned surface were examined by optical microscopy.