Clean Surface Research Articles

Elaboration of an Economic and Efficient Pulp Conditioning Method for a Low-Quality Coarse Coal Slime

ABSTRACT The high energy consumption of high-intensity conditioning (HIC) limits the popularization of this technology although it has been validated as an effective way to improve flotation. In this study, an economic and efficient pulp conditioning method for a low-quality coarse coal slime was innovatively proposed by comparing four different conditioning-flotation processes. It is found that the energy consumption per unit combustible recovery of conditioning using emulsified diesel was reduced by 8.3% compared with that of the conventional conditioning. This is attributed to the energy reduction of the optimum conditioning speed decreased from 2100 rpm to 1300 rpm, and a negligible energy consumed in the preparation of emulsified diesel. Results showed that when using an emulsified diesel, flotation performance was further improved and less affected by conditioning speed but more by conditioning time. Moreover, flotation is no longer affected by the degree of surface cleaning. It was indicated that the dispersion of collector is crucial for HIC. This study provides a technical reference for the development of economic and efficient conditioning equipment.

Small multimodal thermometry with detonation-created multi-color centers in detonation nanodiamond

Detonation nanodiamond (DND) is the smallest class of diamond nanocrystal capable of hosting various color centers with a size akin to molecular pores. Their negatively charged nitrogen-vacancy center (NV−) is a versatile tool for sensing a wide range of physical and even chemical parameters at the nanoscale. The NV− is, therefore, attracting interest as the smallest quantum sensor in biological research. Nonetheless, recent NV− enhancement in DND has yet to yield sufficient fluorescence per particle, leading to efforts to incorporate other group-IV color centers into DND. An example is adding a silicon dopant to the explosive mixture to create negatively charged silicon-vacancy centers (SiV−). In this paper, we report on efficient observation (∼50% of randomly selected spots) of the characteristic optically detected magnetic resonance (ODMR) NV− signal in silicon-doped DND (Si-DND) subjected to boiling acid surface cleaning. The NV− concentration is estimated by continuous-wave electron spin resonance spectroscopy to be 0.35 ppm without the NV− enrichment process. A temperature sensitivity of 0.36K/Hz in an NV− ensemble inside an aggregate of Si-DND is achieved via the ODMR-based technique. Transmission electron microscopy survey reveals that the Si-DNDs core sizes are ∼11.2 nm, the smallest among the nanodiamond’s temperature sensitivity studies. Furthermore, temperature sensing using both SiV− (all-optical technique) and NV− (ODMR-based technique) in the same confocal volume is demonstrated, showing Si-DND’s multimodal temperature sensing capability. The results of the study thereby pave a path for multi-color and multimodal biosensors and for decoupling the detected electrical field and temperature effects on the NV− center.

The capability of diffuse coplanar surface barrier plasma to effectively remove contaminants from surfaces of various materials

AbstractUsing the fluorescence method, the study quantifies the cleaning efficiency of flat surfaces of selected materials (steel, polymethyl methacrylate, glass) compared to the usual cleaning methods: cleaning using ultrasound and cleaning using solutions (ethanol/isopropyl alcohol – isopropanol). Cleaning using ethanol/isopropanol solutions was carried out in such a way as to simulate common procedures: rubbing, rinsing and a combination of application of the solution and ultrasound. Based on the prepared and evaluated (following the average at several places on the surface) values of fluorescence maps of material surfaces, the resulting values of fluorescence before/after cleaning or at the selected moment of degreasing/cleaning of surfaces (applies to steel) were determined. The application of diffuse coplanar surface barrier discharge plasma discharge to the surfaces of flat materials can provide: a reduction in the environmental burden (no chemicals are needed to clean the surfaces) and an improvement in the efficiency of surface cleaning in industrial/manufacturing conditions (plasma cleaning usually takes a few seconds). diffuse coplanar surface barrier discharge plasma can clean and simultaneously activate the surfaces of flat materials.

Multi‐Parametric Decision System for Analytical Performance Assessment of Electrochemical (Bio)Sensors

AbstractMiniaturized three‐electrode electrochemical sensors (MES) are widely used in the advancement of innovative technologies for remote sensing applications. MESs consist of conductive electrodes that are applied onto an inert solid substrate using various techniques, such as photolithography, electroplating, and screen printing. Typical MES systems comprise working (WE) and counter (CE) electrodes based on gold (Au), paired with a reference electrode (RE) based on silver (Ag). This configuration is commonly selected due to Au's high conductivity, low resistance, and compatibility with robust organothiol chemistries, especially for the WE. Moreover, Ag is often preferred for REs owing to its low toxicity, stability, and high conductivity. Nevertheless, in uncontrolled environments outside of cleanrooms, both Au and Ag surfaces are prone to atmospheric contamination, resulting in significant sensor variability and compromised analytical performance. Therefore, it is crucial to integrate a pre‐processing stage into the sensor manufacturing process to guarantee the quality and cleanliness of MES electrode surfaces for sensor functionalization and precise electrochemical measurements. Considering the potential negative effects of methods tailored for a specific electrode material on another material, this study extensively investigates 18 different treatment methods for MESs incorporating Au CEs and WEs, along with Ag REs. Employing a multi‐parametric analysis, this study aims to identify the most effective treatment for a variety of electrode materials, thereby improving analytical accuracy and reproducibility for subsequent MES (bio)sensor applications.

Ecological impact of mechanical cleaning method to curb black stain alterations on Paleolithic cave walls

Anthropization of Paleolithic karstic caves can cause an imbalance of cave microbiota and may trigger formation of wall alterations including black stains. In Lascaux Cave, a previous attempt to mechanically remove black stains was followed by reformation of the stain in months, suggesting that microbial recolonization had taken place. On this basis, we hypothesized that mechanical cleaning (a routine cleaning method for conservation of heritage sites) leaves a residual microbial community that can also serve as pioneer community, i.e. a community of early microbial residents that triggers subsequent microbial successions involved in the reformation of black stains. We monitored post-cleaning microbial recolonization over 19 months in the Apse of Lascaux Cave (France), after using two methods of mechanical cleaning (scalpel alone, or scalpel + sponge). Illumina MiSeq metabarcoding evidenced various taxa i.e. the bacteria Pseudomonas, Pedomicrobium and black-melanized fungi Ochroconis (=Scolecobasidium) during early recolonization of cleaned surfaces, and at later stages the establishment of several other taxa including the bacteria Luteimonas, Chitinophaga and the black fungus Exophiala. Surfaces at 19 months after cleaning were visually and microbiologically different from stained surfaces immediately after cleaned and from unstained surfaces, but also from non-cleaned stained surfaces, probably because of a particular microbial succession, distinct from the original succession during stain formation. Variations in relative abundance of Bacteroidota and Eurotiomycetes classes and Exophiala genus were higher when the sponge was used in addition to the scalpel. The bacteria Filomicrobium and the fungi Isaria and Cephalotrichum were identified on sponge-cleaned surfaces and on the sponge itself, pointing to a contaminant status due to the cleaning method. Overall, it suggests that post-cleaning pioneer communities may play an important role in orienting stain reformation in caves. Sponges routinely used by restorers to curb microbial stains may bring microbial contaminants, which questions current cleaning practices in show caves.

Potential enhancements in the photocatalytic activity of the anatase 001 surface by adding cerium impurity

AbstractThis research investigates the structural and electronic properties of titanium dioxide ($$ TiO_2 $$ T i O 2 ) surfaces with the addition of cerium (Ce) impurities using first principles calculations within the framework of density functional theory, employing the pseudopotential method and the computational package Quantum ESPRESSO. Density of states (DOS) calculations reveal that the clean surface exhibits semiconductor behavior. In contrast, the titanium dioxide surface with Ce impurities on the fifth layer generates intermediate states within the energy band gap, resulting in a reduction in the band, with an intraband energy gap of 0.7882 eV induced. Moreover, the inclusion of a Ce atom on the fourth layer of the surface results it is observed that the surface an important characteristic is the appearance of intermediate states in the band gap, which are close to the valence band with a magnetic moment of 0.91 $$ \mu \beta /cell $$ μ β / c e l l . The ntraband gap can enhance the utilization of the visible spectrum. Additionally, the Ce impurity on the $$ TiO_2 $$ T i O 2 surface could promote greater photocatalytic activity in pollutant degradation and increase the oxidative capacity of titanium dioxide.

Generalized Synthesis of Highly-Dispersed, Ultrafine Transition Metal Nanoparticles on Silica Spheres for Enhanced Optical Absorption.

Robust synthesis of ultrafine metal nanoparticles (ufMNPs) below 5nm with clean surfaces and strong optical absorption in the visible spectral range is challenging due to their instability originating from large surface-to-volume ratios. This work reports a general strategy involving two sequential steps: i) loading metal precursor ions onto the surface of silica nanospheres (SiOx NSs) by forming a uniform coating of metal oxyhydroxide [MOy(OH)z] through preferred surface acid-base reactions and ii) thermally reducing MOy(OH)z in forming gas at elevated temperatures to form ufMNPs evenly dispersed on the surface of SiOx NSs. The capability of this synthesis strategy is verified by loading ufMNPs of various transition metals and bimetallic combinations onto the SiOx NSs. The ufMNPs exhibit strong optical absorption enhanced by the optical scattering resonances in the SiOx NSs, which generate intense electric fields near the surface of the SiOx NSs. The SiOx NSs also support stabilizing the ufMNPs, which do not need additional organic capping reagents. The successful synthesis of SiOx-NS-supported ufMNPs with clean surfaces and enhanced optical absorption is promising for exploring the photocatalytic properties of ufMNPs.

Fabrication of stable monolayer liquid marbles with reduced particle coverage and locomotion on hydrophilic surface

Liquid marbles are non-wetting, particle-covered microdroplets with a core-shell structure that are used in sample transport, material synthesis, and real-time sensing. Optimizing the distribution of shell particles remains a challenge, due to a tendency for aggregation via spontaneous assembly, which often leads to multilayered structures. Here, we outline a simple method for fabricating water-filled, monolayer liquid marbles with adjustable particle coverage rates, greatly reducing particle consumption. The soft liquid marbles are enclosed by a small quantity of modified polystyrene microspheres and display good atmospheric stability. The rolling behavior of flexible liquid marbles with wide coverage rates is then characterized. Contrary to common perception, the marbles with transparent openings exhibit high maneuverability on hydrophilic surfaces, and also excel in fusion, reaction and surface cleaning, with an elongated operational duration and a wide visualization range. The study provides new insights into the implementation of liquid marble-based miniaturized platforms.

Eco-Friendly Sanitization of Indoor Environments: Effectiveness of Thyme Essential Oil in Controlling Bioaerosol Levels and Disinfecting Surfaces.

Bioaerosols and pathogens in indoor workplaces and residential environments are the primary culprits of several infections. Techniques for sanitizing air and surfaces typically involve the use of UV rays or chemical sanitizers, which may release chemical residues harmful to human health. Essential oils, natural substances derived from plants, which exhibit broad antimicrobial properties, could be a viable alternative for air and surface sanitation. The objective of this study has been to investigate the efficacy of thyme essential oil (TEO) in environmental sanitation processes. In Vitro assays through agar well diffusion, disk volatilization and tube dilution methods revealed significant antimicrobial activity of TEO 100% against foodborne and environmental isolates, with both bacteriostatic/fungistatic and bactericidal/fungicidal effects. Therefore, aqueous solutions of TEO 2.5% and 5% were formulated for air sanitation through nebulization and surface disinfection via direct contact. Bioaerosol samples and surface swabs were analyzed before and after sanitation, demonstrating the efficacy of aqueous solutions of TEO in reducing mesophilic and psychrophilic bacteria and environmental fungi levels in both air and on surfaces. The obtained results prove the antimicrobial potential of aqueous solutions of TEO in improving indoor air quality and surface cleanliness, suggesting thyme essential oil as an effective and safe natural sanitizer with minimal environmental impact compared to dangerous chemical disinfectants.

Walnut shells as a promising sorbent for treatment of urban surface wastewater

Food industry is one of the most stable sectors of the global market demonstrating the annual growth of the production output, including in the walnut kernel production, with subsequent generation of waste as a result of its processing. The use of walnut shells as a material for production of sorbents is a promising method of waste disposal. The goal of this research is to evaluate the sorption capacity of walnut shells to clean surface wastewater from urban territories. The object of research was the surface wastewater from urban territories. OPTIMA 2100DV spectrometer (Perkin Elmer), pH-150MI microprocessor pH meter, and JEOL JSM-6460 LV scanning electron microscope were used during the research. The obtained experiment data have shown that walnut shells are a promising material for production of sorbents.

A dual-crosslinking strategy for waterborne polyurethane coatings to achieve outstanding anti-smudge and anti-corrosion properties

The inferior anti-smudge properties and compromised anti-corrosion performance of waterborne polyurethanes (WPUs) stem from the presence of abundant hydrophilic groups in their polymer networks. Despite various hydrophobic segments have been introduced in WPU skeleton to lower the impacts of hydrophilic groups, the limited migration capability of hydrophobic segments in waterborne matrix often result in unsatisfactory performance. Herein, we fabricate a multifunctional PDMS-modulated WPU coating employing sorbitan monooleate (SP), a renewable bio-derived polyol, as an internal crosslink agent, and hexamethoxymethylmelamine (HMMM) as a post-crosslink agent to fully eliminate the polar hydrophilic groups in the molecular linkages and further enhance the crosslink density of the coating. It is found that the coating exhibits exceptional anti-graffiti and self-cleaning effects when subjected to tests involving oil-based and water-based pens and inks, as well as common household liquids like milk, coffee, cooking oil, ethanol, n-hexadecane, etc. Such anti-smudge coating could readily remove carbon powder-like dust with water, ensuring a clean surface, and also possess a certain level of resistance to fingerprint smudges. Apart from excellent mechanical robustness and impressed durability after 500 cycles of writing erase tests, the coating also remains intact and has anti-smudge properties when folded or bent. For chemical resistance, the coating can resist at least 18 h of acid, alkali, and salt intrusion without being damaged. Moreover, the sufficient crosslink density imparts the coating with good thermal stability and outstanding anti-corrosion performance in extremely corrosive environments. This research presents a facile and effective approach for developing stain and corrosion-resistant PDMS-modulated waterborne polyurethane materials with high protective reliability and long lifespan through the dual-crosslinking strategy.

Risk perception and food safety practices among Slovenian pet owners: does raw meat feeding of pets make a difference?

Commercially produced and home-made raw meat-based pet diets are becoming increasingly popular and have been recognised as an emerging public health risk by the European Food Safety Authority. The aim of this study was to investigate risk perceptions and self-reported pet food preparation practices in the home setting among pet owners who feed raw meat-based diet to pets. An online questionnaire was distributed to pet owners through social media groups. Ultimately, 750 respondents were included in the detailed analysis, divided into two subgroups, a “raw group” consisted of pet owners who provided raw meat-based diets for pets (n = 382), while the “conventional group” consisted of pet owners who did not (n = 368). There was no significant difference between the two groups in overall risk perception. Only one third of respondents in both groups were aware of the potentially fatal consequences of food poisoning. Self-reported frequency of hand washing, and surface cleaning, were significantly higher (p = 0.000) in the raw group than the conventional group. Food safety malpractices were noted in the raw feeding group, with 47% reporting to rinsing raw peat meat before preparing it, and 42% thawing frozen raw peat meat at room temperature on the kitchen counter. The results provide information on the prevalence of feeding raw meat to pets among Slovenian pet owners and provides the basis for developing tailored food safety education campaigns to improve risk awareness and provide food safety recommendations for pet owners providing raw meat-based diets for pets in Slovenia.

Effects of Spectrum Loading and break in period using molybdenum disulphide (MoS2) and zinc dialkyl dithiophosphate (ZDDP) as EP additives in lithium based grease

PurposeThe purpose of variable loading conditions (392 N-785N-392N-785N) with break-in period were used to study interactions between zinc dialkyl dithiophosphate (ZDDP) 0.1 P% (phosphorus) and fine-grade molybdenum disulfide (MoS2) 3%, in different mixtures of NLGI 2 lithium stearate grease. Four-ball wear tests were used to evaluate the tribological properties of different grease mixtures such as coefficient of friction and wear. ASTM 2266 as reported by earlier studies is useful, but it is not representative of real-life applications where variable loads and speeds and different break-in periods play a role and could change the results and the nature of tribofilms.Design/methodology/approachIn this study, chemical and mechanical properties of tribofilms were examined. Moreover, design of experiment was used to examine the data and shorten experimentation time. Research described here is investigating variable loading conditions for real-life applications by using a break-in period of 2 min at the start to minimize asperities and establish a clean surface. Design expert (DOE) analyzes responses to reveal those variables that are single factor and those that are multifactor whether synergistically or antagonistically.FindingsThe results indicated that spectrum loading with break-in period showed reduction in wear when tested in greases with ZDDP/MoS2 combinations. Ramping up or down the load every 7.5 min for a rotational speed of 1,200 rpm and a total of 36,000 revolutions or 30-min time slowed the wear properties of lithium-based grease under different MoS2 and ZDDP concentrations. Experiments indicated that wear was largely dependent on the loading condition and ZDDP additives during specific break-in period at 1,200 rotational speed. It is believed that MoS2 greases perform better under spectrum loading and under constant loading when mixed with ZDDP phosphorus.Originality/valueThis research indicates that there is a synergistic interaction between ZDDP, MoS2 and variable loading especially when a break-in period is applied. The results indicated that wear was largely dependent on the specific speed used with spectrum loading as presented in the energy dispersive spectroscopy and the Auger electron spectroscopy analysis, and thus a 3% MoS2 grease with ZDDP (phosphorus: 0.1 Wt.%) are needed to improve the wear resistance and improve the friction characteristics.Peer reviewThe peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-01-2024-0016/

Insect attachment on waxy plant surfaces: the effect of pad contamination by different waxes.

This study focuses on experimental testing of the contamination hypothesis and examines how the contamination of insect adhesive pads with three-dimensional epicuticular waxes of different plant species contributes to the reduction of insect attachment. We measured traction forces of tethered Chrysolina fastuosa male beetles having hairy adhesive pads on nine wax-bearing plant surfaces differing in both shape and dimensions of the wax structures and examined insect adhesive organs after they have contacted waxy substrates. For comparison, we performed the experiments with the same beetle individuals on a clean glass sample just before (gl1) and immediately after (gl2) the test on a plant surface. The tested insects showed a strong reduction of the maximum traction force on all waxy plant surfaces compared to the reference experiment on glass (gl1). After beetles have walked on waxy plant substrates, their adhesive pads were contaminated with wax material, however, to different extents depending on the plant species. The insects demonstrated significantly lower values of both the maximum traction force and the first peak of the traction force and needed significantly longer time to reach the maximum force value in the gl2 test than in the gl1 test. These effects were especially pronounced in cases of the plant surfaces covered with wax projections having higher aspect ratios. The data obtained clearly indicated the impact of waxy plant surfaces on the insect ability to subsequently attach to the clean smooth surface. This effect is caused by the contamination of adhesive pads and experimentally supports the contamination hypothesis.

Tracing the entry process of submicrometre plastics in soybean sprouts by leaf-derived fluorescent carbon dots

As a global emerging contaminant, microplastics (MPs) in water or soil can accumulate in vegetables, making them easily ingested through the diet. With excellent and tunable optical properties, carbon dots (CDs) are highly advantageous for tracing the entry process of MPs. Originally, long-wavelength CDs were synthesized from leaf-derived extracts, and fluorescent submicrometer plastics (CDs-MPs) with clean surfaces and concentrated particle sizes were obtained by soap-free microemulsion polymerization. The concentration of CDs-MPs exhibits a significant linear relationship with long-wavelength fluorescence intensity (λEx/λEm: 415/676 nm). Soybean sprouts (SBS), as an important type of food, are susceptible to contamination of MPs due to their soft epidermis and rapidly growing biomass. The results showed that CDs-MPs could be embedded into the cortex of SBS and enter the plant with cell division and elongation, leading to an increase in pore size on the cell wall surface. After entering the root system, CDs-MPs will pass through the Casparian strip and migrate in the vessels. Then, CDs-MPs enter the leaves through vascular bundles, and the distribution and size of epicuticular wax on leaves have changed. Furthermore, SBS showed resistant growth and increased levels of oxidative response when exposed to MPs/CDs-MPs. It is the first study to demonstrate the application of leaf-derived CDs in the prevention of MPs pollution by revealing the migration behavior of submicrometre plastics in SBS.

Influence of Cylindrical Cells Surface Cleaning by Means of Laser Ablation on Wedge Wire Bonding Process

Wire bonding is a method of connecting two or more surfaces by the means of a thin wire which is ultrasonically bonded to those surfaces and provides an electrical connection. While this method is well established in the microelectronics industry its popularity is rising in the area of cylindrical lithium-ion battery pack manufacturing. Previous studies have shown that even in experimental conditions this process might be unstable which was indicated by the high standard deviation of the bonds shear test results. This might have been related to contamination of the interface area between the joined materials. The aim of this study was to determine the impact of surface laser cleaning on the properties of the wire-bonded joint. The results have shown that laser cleaning with 40% power of the 30 W ATMS4060 laser marker helps to reduce the standard deviation of the shear test results from 16.1% for the uncleaned sample down to 2.6% and greatly reduces the number of oxides within the interface area of the bond cross section. Cleaning with 80% of the laser power did not have a further impact on shear test results and almost completely eliminated oxides from the bonded materials interface.

Mechanisms and economics of a self-powered, automated, scalable solar PV surface cleaning system

PV module exposure to ambient environmental factors, such as dust deposits, have negative effects on the module's peak power (Pmax) and overall power conversion efficiency (η). In this study the ideal counter-acting force needed to remove adhered dust particles on PV modules is investigated. An automated self-cleaning system that uses fluid velocities to suspend adhered dust particles on the PV module surface at a reduced induced static charge induction is designed. The automated system produces lift and drag forces of 3.973 N and 4.563 N per square metre, respectively, which are strong enough to loosen stuck-on dust particles on solar PV surfaces. The model's net present value (NPV) of $ 2383.71 with a dynamic payback period of 1.95 years and profitability index of 1.78 indicate that the investment in the self-cleaning model is financially feasible even for small-scale installations.

Evaluation of Cleaning Soiled Deposits and Crusts from Archaeological Glass Using Laser Treatment with Ag/Au Nanoparticles

The study aims to evaluate the effect of silver and gold nanoparticles during the laser cleaning process of glass artifacts. It is the first time that nanoparticles have been used to clean antique glass, as far as the authors are aware. In the context of this study, work was done on glass samples extracted from excavations that suffer from dense layers of corrosion products, soil deposits, brittle, easy to break, and cannot bear pressure. To characterize the investigated glass shards and assess the cleaning procedure, a variety of analytical techniques, including the transmission electron microscope (TEM), digital microscope, stereomicroscope, scanning electron microscope (SEM-EDX), X-ray diffraction (XRD), and color change measurement, have been used. The XRD analysis revealed different minerals such as ferrosilite, hillebrandite, and jacobsite, in the black corrosion layer, and calcite, syngenite, and arcanite in the white crust layer. The results of the microscopic examination employed in the evaluation procedure demonstrated that using Ag NPs with laser perfectly removed the tough crust layers without scratching the surface. The cleaned surface became smooth, homogenous and more transparent. The elemental analysis results by (SEM-EDX) revealed a significant reduction in the proportion elements of the (Al, Fe, p, and Mg) in the corrosion layer and their loss in the cleaned areas. Measurement of color change indicated that laser-treated glass samples with the addition of Ag NPs gave higher (ΔE*), confirming the influential role of this method in cleaning archaeological glass. It was also observed that the effect of Ag NPs with Laser assistance decreases the required time for the cleaning process. Thus the heat generated by the laser-treated was reduced, so the laser-treated with Ag NPs is recommended for use in the archaeological glass cleaning process.

Large‐Scale Ultrastable 2D Inorganic Molecular Crystal BiBr3 and Heterostructures with Superior Photoluminescence Enhancement

AbstractIn contrast to conventional atomic crystals, two‐dimensional inorganic molecular crystals (2DIMCs) possess a unique crystal structure composed of small molecules held together by van der Waals force. Such distinctive structure grants them specific chemical and physical properties highly suitable for electronic and optoelectronic applications. However, the synthesis of 2DIMCs has posed significant challenges due to the inherent issues such as uncontrollable growth orientation stemming from their natural crystalline isotropy and poor stability resulting from the weak intermolecular connections. Addressing these obstacles, the preparation of large‐scale and highly‐stable 2DIMC BiBr3, and its heterostructure are reported here by developing crystallization orientation engineering strategies. This approach has successfully yielded centimeter‐scale 2DIMC BiBr3 with a clean and dense surface, showcasing exceptional long‐term air‐stability exceeding 80 days. Furthermore, the universal growth of large‐scale 2DIMC BiBr3 is demonstrated on diverse substrates, including SiO2, Al2O3, and MoS2 monolayers. Notably, the resultant 2D BiBr3/MoS2 heterostructure exhibits remarkable photoluminescence enhancement. This contribution paves a universal avenue for the mature synthesis of large‐scale 2DIMCs with superior stability, holding great promise for prompting their integration in practical electronic and optoelectronic devices.

Assessing the impact of a cleaning programme on environmental hygiene in labour and neonatal wards: an exploratory study in The Gambia.

Effective surface cleaning in hospitals is crucial to prevent the transmission of pathogens. However, hospitals in low- and middle-income countries face cleaning challenges due to limited resources and inadequate training. We assessed the effectiveness of a modified TEACH CLEAN programme for trainers in reducing surface microbiological contamination in the newborn unit of a tertiary referral hospital in The Gambia. We utilised a quasi-experimental design and compared data against those from the labour ward. Direct observations of cleaning practices and key informant interviews were also conducted to clarify the programme's impact. Between July and September 2021 (pre-intervention) and October and December 2021 (post-intervention), weekly surface sampling was performed in the newborn unit and labour ward. The training package was delivered in October 2021, after which their surface microbiological contamination deteriorated in both clinical settings. While some cleaning standards improved, critical aspects such as using fresh cleaning cloths and the one-swipe method did not. Interviews with senior departmental and hospital management staff revealed ongoing challenges in the health system that hindered the ability to improve cleaning practices, including COVID-19, understaffing, disruptions to water supply and shortages of cleaning materials. Keeping a hospital clean is fundamental to good care, but training hospital cleaning staff in this low-income country neonatal unit failed to reduce surface contamination levels. Further qualitative investigation revealed multiple external factors that challenged any possible impact of the cleaning programme. Further work is needed to address barriers to hospital cleaning in low-income hospitals.