Effective Cleaning Research Articles

Is differential cleaning needed for SARS-CoV-2 beyond standard procedures? A systematic review

Background: There is a substantial risk of indirect transmission of SARS-CoV-2 from contaminated surfaces and objects in healthcare settings.Aim: To evaluate the effectiveness of enhanced cleaning protocols for high-touch surfaces during COVID-19, focusing on cleaning products, concentrations, contact time, and recommended frequency.Setting: We focused on research conducted in healthcare settings or where samples were obtained from healthcare environments.Method: We assessed studies that compared different cleaning, disinfection, sterilisation, or decontamination procedures and cleaning frequency with standard or routine procedures. We prioritised randomised trials, non-randomised controlled trials, controlled before-and-after studies, and interrupted time series analyses carried out between 01 January 2020 and 31 August 2022.Results: Three studies met our criteria from 2139 references searched. These studies, which took place in Iran, China and the United States, found that routine terminal cleaning and enhanced terminal cleaning with different cleaning enhancements significantly reduced SARS-CoV-2 surface contamination. One of the studies tested residual SARS-CoV-2 levels after routine and terminal cleaning with varying strengths of disinfectant and evaluated the efficacy of two common types of disinfectants in inactivating SARS-CoV-2 on inanimate surfaces in different hospital wards.Conclusion: Limited evidence supports cleaning strategies that can reduce the transmission of SARS-CoV-2 from surfaces in healthcare settings. Combining various cleaning methods and using multiple disinfectants can effectively reduce surface contamination.Contribution: Randomised controlled trials are crucial for evaluating cleaning effectiveness. They must outline cleaning protocols, detailing frequency, product concentration and volume, application methods, soil and surface types, and environmental conditions, to provide strong evidence.

Influence of Different Spot Pattern Lasers on Cleaning Effect of TC4 Titanium Alloy.

This study employed different spot pattern lasers to clean the oxide film on the surface of a TC4 titanium alloy. The variation in temperature field and ablation depth during the laser cleaning process was simulated by establishing a finite element model. The effects of various laser processing parameters on the micromorphology, elemental composition, and surface roughness of the TC4 titanium alloy were analyzed. The results show that as the laser energy density increases, both the temperature field and ablation depth increase as well. Under optimal laser processing parameters, the laser energy density is 5.27 J/cm2, with a repetition frequency of 300 kHz and a scanning speed of 6000 mm/s. A comparison of the cleaning effects of Gaussian pulse lasers and Flat-top pulse lasers reveals that the Gaussian pulse laser causes less damage to the TC4 titanium alloy, resulting in lower oxygen content and roughness values after cleaning compared to Flat-top pulse laser cleaning.

Impact of Water Purity and Oxygen Content in Gas Phase on Effectiveness of Surface Cleaning with Microbubbles

Cleaning of surfaces without complex cleaning agents is an important subject, especially in food, pharmaceutical, and biomedical applications. The subject of microbubble and nanobubble cleaning is considered one of the most promising ways to intensify this process. In this work, we check whether and how the purity of water used for microbubble generation, as well as the gas used, affects the effectiveness of cleaning stainless-steel surfaces. Surfaces contaminated with Pluronic L-121 solution were cleaned by water of three purities: ultrapure water (<0.05 μS/cm), water after reversed osmosis (~6.0 μS/cm), and tap water (~0.8 mS/cm). Similarly, three different gases were supplied to the generation setup for microbubble generation: air, oxygen, and nitrogen. Stainless steel plates were immersed in water during microbubble generation and cleaned for a given time. FTIR (Fourier Transform Infrared Spectroscopy) and contact angle analysis were employed for the analysis of surfaces. The results of cleaning were repeatable between plates and showed different cleaning effects depending on both the purity of water (concentration of ions) and gas composition. We have proposed different mechanisms that are dominant with respect to specific combinations of ion concentration and oxygen content in gas, which are directly connected to the microbubble stability and reactivity of gas.

Study of Method of Evaluating Surface's Pollution Level & Cleaning Efficiency on Decoration Building Materials

In the paper, we analyzed synthetically the research results on methods of testing the cleaning effect on DBM(Decoration Building Materials) and suggested a new Pollution Level & Cleaning Effect Evaluation System(PCEES) on the DBM's surface which is based on image information processing by use of color quantization method and color feature extraction method with HSI (Hue Saturation Intensity) model. By applying the PCEES to many building objects, we could select the effective composition of cleaning agent and cleaning method and calculate the agent's consumption amount necessary for the building work. And we suggested the degree of cleaning effect according to the quantitative result values of evaluation on pollution level & cleaning effect to correspond with the empirical judgment of a man.

Approach for decontaminating large rooms by dry fogging

Abstract Many factors can negatively affect the effectiveness of cleaning and disinfection measures. Due to this situation, the Technical University of Amberg-Weiden in cooperation with aquagroup AG investigated a dry fogging technology as an automated system for decontamination of limited volumes. Preliminary tests in smaller rooms had already shown positive results in this context. An upscaling of the method would therefore be of interest, as it could be used to decontaminate rooms that are difficult or very costly to reprocess due to their size or layout. In order to evaluate the use of this system in operating theaters or larger rooms, a test setup was established in an aquagroup AG painting hall. In addition, thereby the effectiveness of the method can be evaluated in unprepared and unsealed rooms with high ventilation. Our results show a maximum germ reduction of over 5.7 log levels on tiles and 5.2 log levels on plastic. If further studies confirm these initial positive results, the dry fogging we are investigating could be another option for cleaning or disinfecting large areas quickly and effectively.

OPTIMIZATION OF HYDRODYNAMIC PARAMETERS OF DRILLING FLUIDS FOR IMPROVED CUTTINGS TRANSPORT IN HORIZONTAL WELLS

In horizontal portions of small-bore well holes, improper cuttings transportation results in high torque and raises the possibility of the drill being stuck, shortening its service life and endangering safe operation. A transport approach utilizing pulsed drilling fluid based on a shunt relay mechanism is suggested since the traditional cuttings transport method is ineffective at removing the cuttings bed. The transport of cuttings in horizontal small-bore wells is modeled numerically using three layers. The cuttings transport is examined in terms of the cuttings concentration, cuttings velocity, and cuttings bed movement distance using both numerical models and tests. The best pulse parameters are identified by adjusting the pulsed drilling fluid velocity cycle, amplitude, and duty cycle at the annulus inlet and assessing the impact on cuttings transport. The findings demonstrate that pulsed drilling fluid can be used to improve wellbore cleaning, lower cuttings concentration, and increase the cuttings bed's transport distance and moving cutting velocity. A steady flow rate of drilling fluid is used in the traditional cuttings transportation method. Simulations using the three-layer numerical model show that the cuttings bed's movement distance is decreased to the point where the wellbore's cleaning effect falls short of its intended level when the cuttings bed's height in the annulus surpasses a critical value. A technique using pulsed drilling fluid has been suggested to enhance transportation. By altering the drilling fluid's flow rate, this continuously affects the cuttings. Because pulsed jet drilling technology can effectively boost drilling speed, downhole drilling instruments that use pulsed jets are outfitted with spiral pressure intensifiers and variable-frequency pulse jet generators. According to field tests, using pulsed drilling fluid improves cuttings transport efficiency and lessens the impact of chipping. The majority of cuttings transport research to date has been on how cuttings behave under typical drilling fluid flow conditions. Relatively few studies exist about the destruction of the cuttings bed or the transportation of cuttings under conditions of pulsed drilling fluid. This research establishes a three-layer numerical model under pulsed fluid circumstances based on a shunt relay mechanism. This research describes the transport of cuttings in horizontal well sections under pulsed drilling fluid circumstances in terms of factors, such as the cuttings concentration, the cuttings bed's distance traveled, and the moving cuttings velocity, using both numerical models and tests. Furthermore, the ideal pulse parameters are found, which serves as a crucial guide for designing cuttings transport using pulsed drilling fluid tools. A three-layer numerical simulation model of cuttings transport utilizing a pulsed drilling fluid in the horizontal section of a narrow-bore hole is constructed in the second section of the article, which is based on actual onsite working conditions. The experimental apparatus and procedures are presented in the third section, and the experimental data are used to study the behavior of cuttings transport by the pulse drilling fluid. The cuttings transport behavior for various values of th is examined in the fourth section using finite element software. Keywords: CFD model, cuttings bed, pulsed drilling fluid, and horizontal well drilling

The effect of laser cleaning on metallurgical properties and intergranular corrosion behavior of 304 stainless steel

One of the strong possibilities of 304 stainless steel used in the industry is susceptibility to intergranular corrosion. The main purpose of this study is to investigate the effect of the laser cleaning process on the intergranular corrosion of this material. In this paper, 304 stainless steel plates were subjected to laser scanning under four power densities of 3.18×106, 4.77×106, 6.36×106, and 7.96×106 W/cm2, and then sensitized for 4 h at a temperature of 750 ºC. According to practice A in ASTM A262 standard, ditch marks around the grain boundaries were observed in all lasered samples. As a result of bending samples at an angle of 180º according to practice E in ASTM A262 standard, no cracks were observed in the bending area. By performing the ISO 12732 standard, it was found that the ratio of Ir/Ia in all lasered samples was higher than 0.05 and the samples were sensitive to intergranular corrosion, quantitively. A smaller dimension of average grain size was created in the sample lasered at a power density of 4.77×106 W/cm2. In addition, in this sample, the preferred texture of the (220) plane as a non-compressed (220) plane was also observed. Among the lasered samples, this sample had a higher uniform corrosion resistance and achieved a resistance of Rox=78.3 kΩ.cm2. Despite the qualitative approval of the samples (according to ASTM A262, practice E) and their quantitative rejection (according to ISO 12732) regarding the intergranular corrosion, it was suggested to use a power density of 4.77×106 W/cm2 in the case of laser cleaning operations in areas where the laser beam may hit the 304 stainless steel substrates.

Cleaning of Photovoltaic Modules through Rain: Experimental Study and Modeling Approaches

Predicting the amount of soiling accumulated on the collectors is a key factor when optimizing the trade‐off between reducing soiling losses and cleaning costs. An important influence on soiling losses is natural cleaning through rain. Several soiling models assume complete cleaning through rain for daily rain sums above a model specific threshold and no cleaning otherwise. However, various studies show that cleaning is often incomplete. This study employs two statistical learning methods to model the cleaning effect of rain, aiming to achieve more accurate results than a simple totally cleaned/no cleaning answer while also considering other parameters besides the rain sum. The models are tested using meteorological and soiling data from 33 measurement stations in West Africa. Linear regression seems to be a good alternative for predicting the reduction in soiling levels after a rainfall.

Cleaning of Abnormal Wind Speed Power Data Based on Quartile RANSAC Regression

The combined complexity of wind turbine systems and harsh operating conditions pose significant challenges to the accuracy of operational data in Supervisory Control and Data Acquisition (SCADA) systems. Improving the precision of data cleaning for high proportions of stacked abnormalities remains an urgent problem. This paper deeply analyzes the distribution characteristics of abnormal data and proposes a novel method for abnormal data cleaning based on a classification processing framework. Firstly, the first type of abnormal data is cleaned based on operational criteria; secondly, the quartile method is used to eliminate sparse abnormal data to obtain a clearer boundary line; on this basis, the Random Sample Consensus (RANSAC) algorithm is employed to eliminate stacked abnormal data; finally, the effectiveness of the proposed algorithm in cleaning abnormal data with a high proportion of stacked abnormalities is verified through case studies, and evaluation indicators are introduced through comparative experiments to quantitatively assess the cleaning effect. The research results indicate that the algorithm excels in cleaning effectiveness, efficiency, accuracy, and rationality of data deletion. The cleaning accuracy improvement is particularly significant when dealing with a high proportion of stacked anomaly data, thereby bringing significant value to wind power applications such as wind power prediction, condition assessment, and fault detection.

Selective flotation separation of molybdenite from chalcopyrite by ozone nanobubbles preconditioning

To get rid of the conventional toxic depressants, such as NaHS and Na2S, that are currently widely used in Cu-Mo flotation separation practice, a novel ozone nanobubbles preconditioning (ONP) strategy was introduced in this study. Single minerals flotation showed that copper flotation was depressed after ONP, whereas the likewise treated molybdenite maintained its good floatability with the aid of kerosene. Mixed minerals flotation showed that a concentrate containing 53.4 % Mo with 88 % recovery and a separation window of 78 % were obtained after 10 min ONP of bulk Cu-Mo concentrates. X-ray photoelectron spectroscopy (XPS) together with surface xanthate amount determination, infrared spectroscopy and surface wettability characterization were employed to understand the underpinning mechanism. It appears that in addition to the formation of hydrophilic oxidation products as well as the removal and destroy of xanthate on chalcopyrite surface, the rapid and complete decomposition of xanthates in flotation pulp solutions by ONP may also contribute to the depressed copper flotation after ONP. It is interesting that the unfavorable cleaning effect of ONP on the floatability of molybdenite was compensated by a further addition of kerosene.

Superhydrophilic and porous carbon nanofiber membrane for high performance solar-driven interfacial evaporator

In light of the mounting global water crisis, solar interfacial evaporation has emerged as a pivotal technology for the advancement of water resource management. One of the most effective methods for enhancing the evaporation rate of solar evaporators is to optimize their utilization of light. In this study, a superhydrophilic Cu/C porous fiber evaporator was prepared using a multi-fluid electrospinning technology and a thermal treatment method. This evaporator exhibits excellent evaporation performance under the effect of Cu NPs, carbon fiber and a porous structure. The results demonstrated that the evaporation rate of the evaporator could reach 1.41 kg m−2 h−1 under one sunlight irradiation (Evaporation efficiency of 94.6 %). In addition, for wastewater containing organic dyes, acidic and alkaline, the evaporator has a significant cleaning effect. This high photothermal conversion efficiency suggests a promising avenue for the utilization of solar energy in water purification.

Gel Cleaning in Heritage: Comparison of the Water Release among Gels and Traditional Pads.

Water release is a crucial aspect when considering cleaning effects on water-sensitive materials. In conservation practice, a water-based cleaning method which limits water release is very often needed. Unfortunately, this is not accompanied by an appropriate measure of the effectively released water. In this paper, water release has been measured by comparing traditional cleaning formulations, such as paper pulp and sepiolite, with several gar gel formulations, used by both Italian and European conservators. The assessment has been carried out by the gravimetric method, using three different stone material specimens as reference: Noto calcarenite, Manciano sandstone and Black Bergamo limestone, whose porosity values and distributions are known. Moreover, water distribution has been evaluated by portable NMR tests. Different commercial agar gel products (Bresciani, CTS, Sigma), having different concentrations (3, 4, and 5%), application modes (rigid at room T or fluid warm gels, with and without inserting Japanese tissue paper), and geometry (horizontal in gravity force direction or vertical), have been compared to obtain a full scenario among different water release mechanisms present in real conservation works. The paper faces the important issue of preparing reproducible chemical or water pads as well, useful for further research aimed at comparing cleaning effects in heritage conservation. The most interesting quantitative results can be summarized as follows. The water release measured from paper pulp and sepiolite was found to be 2 to 4 times higher than from any tested agar gel. Water release decreases by increasing agar concentration; an increase in the agar concentration by 1% induces a decrease in water release in the range 16.98-66.88 g depending on the stone; the increase from 4% to 5% is more obvious with respect to that from 3% to 4%. It is possible to assess the effect of the presence of Japanese paper, which is able to reduce the water release from 18 to 76%, depending on the stone and on the agar used. The gravimetric results were also used in the preliminary calibration tests of a contact probe named System Unit Salinity Index (SUSI), recently patented and useful in providing humidity and salinity indexes in a given porous material.

Effect of rare earth Ce treatment on the microstructure and properties of 430 ferritic stainless steel bearing Sn and Cu

The effects of rare earth Ce on purifying molten steel, modifying inclusions and micro-alloying in 430 ferritic stainless-steel bearings with Sn and Cu has been studied in this paper. The results demonstrate that Ce can purify molten steel, modify inclusions, enhance the mechanical properties and improve the pitting and corrosion resistance of the experimental steel. Ce effectively purifies the molten steel, reducing the total oxygen (T. O) content to as low as 0.00086 wt.% and sulphur (S) content to 0.0020 wt.%. The transformation of inclusions in the steel follows the sequence of MnS·Al2O3 → CeAlO3 → Ce2O2S → Ce2O3 with increasing Ce content. The number of inclusions initially decreases and then increases, with the experimental steel containing 0.012 wt.% Ce showing the best cleaning effect. Additionally, Ce treatment only slightly improves the mechanical properties of the experimental steel, but significantly enhances its pitting corrosion resistance and intergranular corrosion resistance by changing the enrichment state of carbides and impurity elements at the grain boundaries. In detail, Ce can partially inhibit the precipitation of M23C6 type carbides at grain boundaries, thereby improving the intergranular corrosion resistance of the experimental steel.

Assessing effectiveness of cleaning and disinfection of equipment and environmental surfaces in cystic fibrosis clinics using an ATP assay.

Infection control guidelines for cystic fibrosis (CF) stress cleaning of environmental surfaces and patientcare equipment in CF clinics. This multicenter study measured cleanliness of frequently touched surfaces in CF clinics using an ATP bioluminescence assay to assess the effectiveness of cleaning/disinfection and the impact of feedback. Eight surfaces were tested across 19 clinics (10 pediatric, 9 adult) over 5 rounds of testing. Rounds 1 and 2 served as uncleaned baseline, and Round 3 occurring after routine cleaning. Rounds 4 and 5 were performed after feedback provided to staff and measured after cleaning. Pass rates defined as <250 relative light units were the primary outcome. Of the 750 tests performed, 72% of surfaces passed at baseline, and 79%, 83%, and 85% of surfaces passed in Rounds 3, 4, and 5, respectively. The overall pass-rate was significantly higher in adult compared to pediatric clinics (86% vs 71%; P < 0.001). In pediatric clinics, blood pressure equipment and computer keyboards in the pulmonary function lab consistently passed, but the exam room patient/visitor chairs consistently failed in all rounds. In adult clinics blood pressure equipment, keyboards in exam rooms and exam tables passed in all rounds and no surface consistently failed. We demonstrate the feasibility of an ATP bioluminescence assay to measure cleanliness of patient care equipment and surfaces in CF clinics. Pass rates improved after cleaning and feedback for certain surfaces. We found that surfaces are more challenging to keep clean in clinics taking care of younger patients.

Analysis of the influence of changing the diameter of peg drums on the effectiveness of cleaning of raw cotton from small impurities

Analysis of the influence of changing the diameter of peg drums on the effectiveness of cleaning of raw cotton from small impurities

Application of Low-Temperature Air Plasma for the Enhancement of Defense Fabric's Self-Cleaning Property.

Self-cleaning textiles have the potential to revolutionize the lives of people like military personnel and hikers who spend extended periods of time in the sun and have restricted access to washing facilities. This research aims to develop the self-cleaning capability of defense uniforms by utilizing air plasma treatment and applying TiO2 nanocoating. Following plasma treatment of differing durations (2, 4, 6, 8, and 10 min, respectively), a pad-dry cure method was employed to apply a TiO2 coating to each sample, while keeping other processing parameters constant. SEM, Fourier transform infrared spectroscopy, ultraviolet protection factor (UVPF), energy-dispersive X-rays, and a water contact angle test were performed in order to validate the air plasma-induced surface modification. There was a gradual escalation in the rate of TiO2 absorption with an extension of the plasma treatment duration. Afterward, the samples were stained with various organic and inorganic compounds, including oil, ink, soil, and coffee, and subsequently exposed to sunlight for a period of 6 h. The samples demonstrated an enhanced cleaning effectiveness with increasing quantities of TiO2. The reflectance value and visual assessment of washed sample showed a reduced yet still present self-cleaning characteristic. The UVPF of the samples increased gradually as the duration of plasma treatment increased due to the UV absorption properties of TiO2, as validated by measuring the band gap energy.

Optimizing Magnetic Separation and Cleaning Module in Fully Automated Chemiluminescence Immunoassay Analyzer Using a Special Arrangement of Spliced Magnets and a Three-Stage Magnetic Bead Collection Method

The magnetic separation and cleaning module, as a core component of the fully automated chemiluminescence immunoassay (CLIA) analyzer, encounters issues including high magnetic bead loss rate, long cleaning time, and poor cleaning effect. Based on a simulation analysis using COMSOL, we proposed a novel magnetic separation and cleaning module applied to a fully automated CLIA analyzer. The module adopted a method of arranging spliced rectangular magnets on opposite sides, where the same polarity faced each other, as well as a three-stage magnetic bead collection method. With the proposed method, the total cleaning process can be accomplished within 225 s; the total magnetic bead loss rate over three rounds of cleaning is 6.03%, whereas that of traditional instruments is 25.85%; the coefficient of variation (CV) of the magnetic bead loss rate is less than 0.5%; effective cleaning of free markers is achieved under various sample conditions. Compared with traditional CLIA instruments, this method comprehensively improves key performance indicators of the magnetic separation and cleaning module, providing a reference for similar modules in fully automated CLIA analyzers and positively impacting the accuracy of CLIA for the detection of disease biomarkers.

Contamination patterns of the neonatal equipment, major microorganisms, and effectiveness of disinfection procedures including refurbished UV C lights at the University Teaching Hospital of Butare (CHUB)

A contaminated environment plays a significant role in transmitting hospital-acquired infections (HAIs) but regular chemical disinfection is the backbone for tackling this chain of transmission and the combination of both UV lights may increase the effectiveness of cleaning. This study assessed the effectiveness of chemical disinfection, with and without additional UV light exposure, in reducing bacterial contamination in a Neonatal unit. Therefore, interventions consisted of usual chemical disinfection with and without a 2-hour exposure to Ultraviolet light from refurbished UV lamps. Researchers swabbed high-touch surfaces and equipment before and after disinfection to identify bacterial presence. They found that 36.4% of the sampled sites showed bacterial growth, with the nursing trolley being the most contaminated. The most common bacteria isolated was Klebsiella pneumoniae (50%), which, along with other bacteria, displayed high resistance to commonly used antibiotics like Amoxicillin + Clavulanic acid and Cefuroxime. Only Meropenem and Amikacin remained effective. The study concludes that despite chemical disinfection, bacterial contamination remains significant, and conventional UV light alone did not completely eradicate bacteria, highlighting the need for more effective disinfection strategies. Keywords: Neonatology Service, University Teaching Hospital of Butare (CHUB), hospital-acquired infections (HAIs), disinfection

Implementasi K-Nearest Neighbor Pada Klasifikasi Prospek Waralaba

Franchising is currently a promising business process where many types of franchises are currently mushrooming and growing rapidly. An algorithm is needed that can classify the type of franchise according to existing attributes. The K-Nearest Neighbor algorithm can produce robust or clean data and effects even for large data sets. The K-Nearest Neighbor algorithm is an algorithm that is able to classify franchise types with an accuracy value of 92.23%. With this high accuracy, it can be ensured that the classification can be clearly seen, where according to the research it was found that the very prospective and prospective classes are in Bakmi Gila and Alfamart. That way, you will get maximum profits by choosing the right franchise

Cleaning of laser-induced periodic surface structures on copper by gentle wet chemical processing

Laser-induced periodic surface structures (LIPSS) attract considerable attention due to the manifold applications enabled by these self-organised structures ranging from optical colouring to bio-mimicking or wetting effects. The mechanism of LIPSS-formation at metal surfaces includes laser-ablation processes that results in phase transitions, explosive material removal and partial redeposition of the ablation products in the form of nanoscopic debris or even sub-micrometre-sized spherical particles in case of melt ejection. For some applications, these particulates, debris, and microscopic features on top of the periodic surface structures are disadvantageous. We studied wet-chemical cleaning approaches to remove redeposited material from LIPSS to enhance their applicability. LIPSS on copper with a lateral periodicity of ∼ 365 nm, that were fabricated by ultrashort pulse laser exposure(λ: 515 nm, tp: 260 fs), were cleaned with different liquids ranging from solvents to microemulsions. The surface morphologies were characterised by scanning electron microscopy (SEM), atomic force microscopy (AFM) and transmission electron microscopy(TEM) to study the surface topography, the size and density of surface particulates as well as other surface contaminations before and after wet cleaning. The LIPSS surface composition was analysed by X-ray photoelectron spectroscopy (XPS), Raman spectroscopy and Energy-dispersive x-ray spectroscopy (EDX) at the FIB-cross sections. The different cleaning approaches are classified with respect to their capability to remove particles and contaminations as well as to their influence on the morphology and shape of LIPSS pattern, whereby substantial differences are found. At least two wet-chemical solutions enable the removal of nanoparticles with only minor modification of the LIPSS topography. The main effect of wet cleaning is the detachment of particulates including sub-micrometre-sized spheres due to a gentle and selective etching of the interface region between the LIPSS and the redeposited material that comprise of modified copper and copper oxides.