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Microbial-based cleaning products (MBCPs) have been introduced, on the market, as an alternative to traditional chemical cleaning. In addition to traditional detergents, MBCPs can perform their cleaning function, digesting the smallest particles of dirt and mitigating odours generated by environmental bacterium metabolic processes. Nevertheless, several aspects remain to be clarified and assessed, requiring further studies and new regulations to ensure safety. The particular composition of MBCPs makes it difficult to include these products in a specific class, making the European legal context incomplete and unclear. Moreover, MBCPs effects on human health are poorly documented. Exposure risks can be obtained indirectly by studies conducted in both microorganisms exposure and their metabolic products, such as enzymes, especially in workers. A further limiting factor for the accurate human health risk assessment due to MBCPs use is an incomplete indication about the MBCPs compositions. Moreover, additional factors such as host microorganisms, frequency and space of use, subject health condition, and age can determine different illness scenarios. The findings from the broad range of studies we have reviewed in this paper confirm the necessity of integrative investigation and regulation to address the use of MBCPs.

This study aimed to identify the recommendations of orthodontists practicing in Turkey to their patients regarding the cleaning of removable orthodontic appliances (ROAs) and to analyse whether their advice was promoted by the coronavirus disease of 2019 (COVID-19) pandemic. A questionnaire link was sent via an e-mail to 1018 members of the Turkish Orthodontic Society,including an informative letter about the study. A total of 133 orthodontists answered the questionnaire acceptably. Almost all participants of this study recommended their patients to brush ROAs (94.7%). A majority of orthodontists advised to use a cleaning agent besides brushing. Patients were advised to brush generally two or three times a day and use the cleaning agent less often. A total of 77.4% of the participants stated that the COVID-19 pandemic did not change their recommendations regarding the cleaning of ROAs. A prevalent cleaning method advised by respondents was brushing. Taking into consideration the COVID-19 pandemic, orthodontists in Turkey had better increase prescription of a chemical cleaning agent for ROAs.Please click here for the supplementary survey.

Oil-based drilling fluids are widely used in oil and gas exploration and development. Large amounts of oily drilling cuttings are produced in the drilling process, and improper treatment can cause serious secondary pollution. Chemical cleaning is commonly used to treat oily drilling cuttings. However, most degreasing agents are not environmentally friendly and can cause secondary pollution. Thus, the processing requirements of oily cuttings are difficult to meet. In this study, an environmentally friendly degreasing agent CYJ-1 that is biodegradable and can efficiently treat oily drilling cuttings was designed and prepared using optimized treatment agents and conditions, achieving an oil removal rate of 93.02%. In addition, a harmless degreasing formula utilizing this environmentally friendly degreasing agent was developed and had a remarkable oil removal effect on oily drilling cuttings. Transition state theory was applied to explain the degreasing effect of oily drilling cuttings for the first time, and the mechanism of action of the degreasing agent was analyzed in conjunction with the interfacial tension and potential energy. The formula was applied at two wells in the Xinjiang oilfield in China. It could achieve a high oil removal rate, which efficiently solved the pollution and resource recovery problems associated with oily drilling cuttings.

The scaling of the water injection pipeline seriously affects the water injection efficiency. Current research is generally limited to the selection of suitable cleaning technology, and there are too few studies on the cleaning effect. In this paper, after analyzing the scaling mechanism and scaling evaluation model of the water injection pipeline, a simulation system is designed based on the GUI interface of the MATLAB platform to simulate the cleaning effect. The original data of the oilfield water injection pipeline can be imported into the simulation system, the cleaning technology can be selected and its cleaning effect can be simulated, and the evaluation method of the cleaning effect is given in the paper. The cleaning result can be obtained by comparing the data before and after cleaning. Based on the original data of an oil field, this paper carried out a simulation of the cleaning effect of chemical cleaning, and reached a conclusion that the cleaning effect was obvious. Application examples show that the water injection trunk lines that need to be cleaned in the two water injection stations have been obviously improved after cleaning, but the cleaning effect of different water injection stations is different, so the cleaning technology can be adjusted in time according to the simulation, which is more conducive to the choice of pipeline cleaning technology, thereby improving water injection efficiency.

Hospital-acquired infections (HAIs) pose a serious threat to patients, and hospitals spend billions of dollars each year to reduce and treat these infections. Many HAIs are due to contamination from workers’ hands and contact with high-touch surfaces. Therefore, we set out to test the efficacy of a new preventative technology, AIONX® Antimicrobial Technologies, Inc’s cleanSURFACES®, which is designed to complement daily chemical cleaning events by continuously preventing re-colonization of surfaces. To that end, we swabbed surfaces before (Baseline) and after (Post) application of the cleanSURFACES® at various time points (Day 1, Day 7, Day 14, and Day 28). To circumvent limitations associated with culture-based and 16S rRNA gene amplicon sequencing methodologies, these surface swabs were processed using metatranscriptomic (RNA) analysis to allow for comprehensive taxonomic resolution and the detection of active microorganisms. Overall, there was a significant (P < 0.05) global reduction of microbial diversity in Post-intervention samples. Additionally, Post sample microbial communities clustered together much more closely than Baseline samples based on pairwise distances calculated with the weighted Jaccard distance metric, suggesting a defined shift after product application. This shift was characterized by a general depletion of several microbes among Post samples, with multiple phyla also being reduced over the duration of the study. Notably, specific clinically relevant microbes, including Staphylococcus aureus, Clostridioides difficile and Streptococcus spp., were depleted Post-intervention. Taken together, these findings suggest that chemical cleaning events used jointly with cleanSURFACES® have the potential to reduce colonization of surfaces by a wide variety of microbes, including many clinically relevant pathogens.

IntroductionRoot canal treatment, including pulp removal, mechanical and chemical cleaning, and canal filling is an important part of a dentist's job. This study aimed to evaluate the quality and success rate of root canal therapy performed by dentistry students in the Department of Endodontics, School of Dentistry, Birjand University of Medical Sciences, Birjand, Iran.MethodsThis retrospective study was conducted from 2014 to 2017. In total, 62 students were randomly divided into two equal groups of males and females. For each tooth, four radiographs, including the periapical images of the initial radiograph, master apical file, master cone, and final obturation radiographs, were reviewed under the supervision of an endodontist. The investigated technical errors included transport, ledge, perforation, underfilling, overfilling, and presence of void and broken instrument. Data were analyzed in SPSS software (Version 22). A P-value less than 0.05 was considered statistically significant.ResultsAccording to the results, only 79.3% of the students committed at least one type of root healing error, and there was no significant difference between males and females regarding the overall prevalence of error (P=0.12). However, errors, such as underfill, broken instrument, and transport were more common among males; moreover, void and perforation errors were slightly more prevalent among females. It should be noted that this difference was not statistically significant.ConclusionsThe results of the present study can help identify the weaknesses of treatment in order to improve the quality of root canal treatment, especially regarding student gender in the School of Dentistry affiliated to Birjand University of Medical Sciences, Birjand, Iran.

Introduction Successful endodontic treatment vastly depends to a high degree on an accurate knowledge of root canal system morphology. It is a prerequisite to be aware of all possible reservoirs where bacteria and/or toxins can persist, compromising the surrounding tissues; such knowledge results in endodontic success. Methods The presence of interradicular canals and diverticula between the pulp chamber floor and the bifurcation area surface of 117 mandibular first molars was investigated. Access cavities were prepared, the teeth were embedded in plastic, and the pulp chambers were flooded with methylene blue and then centrifuged. An average of 4.2 (0.145 ± 0.03 mm thickness) slices per tooth were obtained by means of a diamond band saw. The presence of interradicular canals and diverticula was investigated using a light microscope (125×). Results Interradicular canals were observed in 9 teeth. Seven teeth had 1 interradicular canal, and 2 teeth had 2 interradicular canals. Diverticula (blind interradicular canals) were observed in 11 teeth originating either on the pulp chamber floor or the bifurcation side. The number of diverticula per tooth varied between 1 and 5 and originated in 3 teeth in the pulp chamber floor and 8 teeth in the bifurcation area. Two teeth had both 1 interradicular canal and 3 diverticula. Of the 117 mandibular molars investigated, 18 had either 1 or 2 interradicular canals, 1 to 5 diverticula, or an interradicular canal and 3 diverticula. Conclusions Based on the results obtained with this ex vivo study and because of the difficulties involved in the clinical performance of mechanical cleaning of possibly existing interradicular canals, it is highly recommended to perform thorough chemical cleaning and disinfection of the pulp chamber floor area in order to enhance the sealing possibility of such structures and minimize treatment failure.

Reliable operation of steam boilers is maintained by periodic in-service cleanings of the internal surfaces of the steam-water path. Such cleanings can be made with traditional and new acid cleaning agents. The nec-essary condition for developing an effective chemical cleaning program is predicting its required duration taking into account the properties of the detergent used and the contamination of the metal surface. Insufficient duration of this operation leads to increased residual contamination, while excessive duration – to metal dissolution. Traditionally, the required time for chemical cleaning is evaluated according to the results of laboratory experiments. The aim of this study is to obtain analytical dependencies and characteristics describing the kinetics of the acid stage of steam boiler chemical cleaning. The laboratory studies of the acid stage of chemical cleaning of samples of high-pressure steam boiler generating tubes were performed by the chemical etching method. The rates and completeness of the removal of lumpy and uniform deposits by acid reagents were also determined. The method of mathematical modeling was used to obtain the kinetic equation. The conditional purification rate constants for this equation were found by the methods of statistical processing of laboratory results. A description of the scale removal rate from the inner surface of the steam generating tubes is proposed as a first-order kinetic equation depending on their specific contamination and reagent washing solution acidity. The equation allows calculating the required duration of chemical cleaning for providing a given value of specific residual contamination of the metal surface. According to the results of the laboratory studies, the conditional rate constants of purification were determined using proven detergent reagents and types of scale. The adequacy of the obtained results is ensured by their consistency with real-life data. The results of the study can be used to select the technology of acid stages of chemical cleaning of lumpy and uniform deposits and justify their duration for providing standard values of specific residual contamination of the surface of steam generating tubes of drum boilers.

Many industrial applications require careful regular or periodic cleaning of inner regions of metallic elements such as citerns, tanks or tubes [1] . Techniques like sandblasting or chemical cleaning are often unsuitable as they cannot allow proper control of the progress of the cleaning process and because they cannot apply for hardly accessible regions. For addressing both issues, we report in this communication an endoscopic cleaning system based on the use of short energetic light pulses directed towards the area to be scoured by means of an endoscopic optical fiber, and completed by a remote real time Laser Induced Breakdown Spectroscopy (LIBS) analysis system.

INTRODUCTION: Effective irrigant delivery and agitation protocols with recent advances in magnification, endodontic instruments, and obturation systems can lead to more conservative access opening designs. OBJECTIVES: The purpose of this in vitro study was to compare the cleaning of the root canal system with 2 different designs of access opening, traditional versus conservative. METHADOLOGY: 100 extracted upper premolars were divided into four groups according to the access opening performed: Gp I and Gp III Conservative endodontic access, GpII, and IV traditional access opening. Then all teeth were autoclaved, inoculated with Enterococcus faecalis, and incubated for 30 days. Gp I and Gp II were then prepared with Wave One Gold and irrigated with Passive ultrasonic irrigation while Gp III and Gp IV were not instrumented and served as negative control. Finally, all samples were decalcified and submitted to staining by Brown and Brenn stain. RESULTS: The traditional access opening design showed better cleaning than conservative access. The obtained results showed statistical significance between the two access opening designs regarding the chemical cleaning. CONCLUSIONS: Conservative and conventional access cavities exhibited different cleaning outcomes. Endodontic microscope assisted conservative access could not be done as a valuable alternative for conventional access without hindering cleaning.

Surface cleaning has always been an important procedure to improve quality and performance of final components in modern industrial manufacturing. Among various surface cleanings, laser cleaning has been identified as the most promising green cleaning technology to replace conventional mechanical and chemical cleaning. Laser cleaning is a green cleaning technology that will not result in environmental pollution. And, laser cleaning is a versatile, precise, and controllable technology. A set of laser cleaning system that consists of line structured light and industrial manipulator, was designed in this paper. The line structured light, combined with camera, was used to scan workpiece surface and reconstruct the 3D model of workpiece surface. The industrial manipulator was utilized to perform scanning and cleaning movements. This new system is called Laser Cleaning Robot (LCR). To improve automation level and cleaning efficiency of the LCR, a path generation method based on line structured light and industrial manipulator was proposed in this paper. Experimental results demonstrate the performance of the proposed method in terms of cleaning efficiency for large-scale workpiece.

Organic fouling in the forward osmosis process is complex and influenced by different parameters in the forward osmosis such as type of feed and draw solution, operating conditions, and type of membrane. In this article, we reviewed organic fouling in the forward osmosis by focusing on wastewater treatment applications. Model organic foulants used in the forward osmosis literature were highlighted, which were followed by the characteristics of organic foulants when real wastewater was used as feed solution. The various physical and chemical cleaning protocols for the organic fouled membrane are also discussed. The study also highlighted the effective pre-treatment strategies that are effective in reducing the impact of organic fouling on the forward osmosis (FO) membrane. The efficiency of cleaning methods for the removal of organic fouling in the FO process was investigated, including recommendations on future cleaning technologies such as Ultraviolet and Ultrasound. Generally, a combination of physical and chemical cleaning is the best for restoring the water flux in the FO process.

The global wastewater treatment capacity of MBR has been constantly growing due to the strong needs in water reuse/cycle and restrictive availability of land. Recent research revealed generation of a variety of halogenated organics during online chemical cleaning of MBR with sodium hypochlorite (NaClO) which has been commonly practiced for fouling control and permeability recovery of MBR. These exogenous halogenated organics may likely migrate into natural water bodies and soils through the discharge of MBR permeate, while they tend to bioaccumulate in aquatic food chains (e.g. aquatic animals and plants), leading to a dangerous concentration level for human health. It should be realized that the potent environmental and public health risks associated with produced halogenated organics in MBR permeate have not yet been aware and assessed in consideration of the entire water life cycles. Therefore, this article attempts to express serious concern on, while raising scientific and public awareness on this emerging issue.

Historical textiles exposed in museum to processes of deterioration factors. Therefore, adhesives and polymers used to fix and strengthen weak textiles. These adhesives are prone to stiffness, weakness, and color change and rigid after long term and other damage. Therefore, this research attempts to use nanotechnologies to improve the properties of polymers used in historical textiles conservation. Results of the physical, chemical and optical properties of the Beva 371 and Nano-Vinyl acetate derivatives and apply it to fix and strengthen the historical textiles was present. The dyed wool fabrics by natural dyes treated with Beva 371 and Nano Vinyl acetate derivatives adhesive. Accelerated thermal ageing done of treated wool fabrics. A close examination and test were done by using SEM-EDX, FTIR, Tensile strength , Elongation, the colors change (CIE L*a*b*) coordinates. The final step is applied the Nano-Vinyl acetate derivatives on Historical Coptic Textiles. Scientific examinations, the stability of dyes and fibers, mechanical and chemical cleaning processes, Fixing and strengthening of historical textiles on new support by using Nano- Vinyl acetate derivatives done. The article presents, for the first time, interesting and important results of Beva 371 and Nano- Vinyl acetate derivatives and its application on the historical textile.

The procedures used for cleaning metallic wind instruments are: mechanical, chemical and with ultrasound. Mechanical cleaning is mostly used for current maintenance. Chemical cleaning is used for tarnish removal. Ultrasonic cleaning was developed for cleaning small delicate metallic mechanism. The spectacular development of this technique has its origin in the industrial development of generators and transducers using high power ultrasonic energy. The efficiency of ultrasonic cleaning procedure depends on the cavitation process induced by ultrasonic vibrations. One of the most efficient processes is the sterilization of wind musical instruments using ethylene oxide as a gas sterilizing agent, acting by diffusion. This process seems to be most appropriate for woodwind instruments. The main advantage of the sterilization procedure of wind instruments is substantially diminishing or completely reducing the probability of players’ infections with microbes, bacteria and viruses normally residing in such instruments.

Surface treatment is necessary in a host of industries to attain a defect-free surface. In medical and semiconductor fields, for example, clean surfaces are essential to provide good adhesion across multiple interfaces. Conventional treatment methods such as wet chemical cleaning or solvent degreasing can effectively increase the wettability of surfaces and thereby the adhesion, or decrease the contact resistivity. However, a massive disadvantage of these techniques is that they leave the treated surface contaminated with traces of process chemicals and generate residues that are difficult to dispose of and are harmful to the environment. Due to the health concerns of these techniques, dry cleaning techniques such as plasma cleaning are currently being explored by researchers around the globe. In this chapter, a comprehensive review of the current and past work on plasma cleaning applications along with the fundamentals and advantages of plasma cleaning will be discussed.

On a daily basis, individuals are exposed to potential poisoning by different sources such as medicines, food, alcohol, pesticides, and chemical cleaning materials. In these circumstances, individuals often need to undergo medical emergency interventions to manage the serious consequences that can appear simultaneously with the poisoning or in the long term. Indeed, the nature and circumstances of daily poisoning cases vary among socio-demographic backgrounds. This fact requires the development of a medical emergency system that integrates emergency toxicity treatments. This perspective further suggests the development of appropriate prevention and treatment programs according to the geographical distribution of the recorded daily poisoning incidences. A database was built in regards to the many acute poisoning cases recorded in a number of emergency facilities based on four geographical zones in Syria. The data included the source of the poisoning and the individual’s identity demographics, like age, gender, profession, the area of residence, and employment. The statistical analysis proved that there is an evident relationship between the types of daily poisonings and the demographics of the individuals poisoned including the geographical location. Thus, this study showed the importance of developing a probabilistic mapping on a national scale of the possible daily poisoning incidents based on the individuals’ demographics. Furthermore, this approach allows local and national authorities to develop anti-poisoning centers and provide the equipment and most appropriate medical materials according to the needs of each region.

This article describes the types of dirt that may appear on the surface. Inner surfaces may be embedded by one of the insertion mechanisms or a combination of these mechanisms. The article also deals with methods of internal surface cleaning and experimentation. A suitable choice of detergent on the basis of the analysis and its subsequent application have confirmed the appropriate choice and finding the optimal technological parameters to restore the original working parameters of the cleaned equipment.

Ultrafiltration as a pretreatment for RO feedwater with enhanced UF backwash, which combines continuous with pulse backwash, was investigated in a novel UF-RO process integration. Direct supply of RO concentrate to the UF module served for UF backwash which was further enhanced with pulse backwash generated using bladder-type hydraulic accumulators. Model analysis of the hydraulic accumulator operation, which was validated via a series of field experiments, demonstrated a capability for accumulator charging directly from the RO concentrate stream within a period of 30–40 s. Moreover, pulse backwash over a short period (~5 s) which was added to the continuous UF backwash (directly from the RO brine stream), enabled peak UF backwash flux up to a factor of 4.2–4.6 higher than the normal filtration flux. The above mode of UF operation with multiple consecutive backwash pulses was more effective than with a single pulse, while inline coagulation further increased the UF performance. Relatively long-term field operation (over eight days where) of the UF-RO system with self-adaptive triggering of UF backwash, whereby the number of consecutive pulses increased when a higher membrane fouling resistance was encountered, was highly effective in enabling stable UF operation over a wider range of water quality conditions and without the need for chemical cleaning. These encouraging results suggest that direct UF-RO integration with enhanced pulse UF backwash is an effective approach for dead-end UF filtration without sacrificing water productivity.

Features of the choice of solvents for the physical and chemical cleaning of power optical elements in accordance with the parametric solubility theory were investigated. When cleaning the surface from the model contaminant with halogenated hydrocarbons, visually observed white film of alkali and alkaline earth metal salts that are not soluble by this class of solvents and iridescent bands from the interaction of hydrocarbons with the metal remain on the surface. All this greatly impairs the optical properties of the surface. It was shown that, when using solvents, it is necessary to inhibit the interaction of halogenated hydrocarbons with mirrors by stabilizing solvents or by selecting the regimes for carrying out the physicochemical purification process, or by thereof combination.

The purpose of a wafer-cleaning step is to remove surface particles as well as organic and inorganic contaminants, and to prepare a "clean" surface prior to specific process steps. To evaluate a wafer-cleaning technique, one must realize that a wafer-cleaning process is actually a chemical process designed to achieve a desired electrical result. The RCA cleaning process is based on oxidation and dissolution of residual organic and certain metallic impurities. In the RCA cleaning process, there is clearly a tradeoff between metallic removal rates and particle deposition rates. Recent developments have been reported on the use of dry wafer-cleaning processes as a replacement for wet chemical cleaning processes. Dry cleaning processes can be of much higher purity than wet processes, in part because of the higher degree to which a gas can be purified and filtered.

This chapter reviews monitoring of wet chemical cleaning, etching, and surface conditioning processes. The online monitoring techniques that are presented are near-infrared spectroscopy, conductivity, and resistivity. Real-time chemical analysis is reviewed. The principles of spectroscopy are discussed, as well as suitable instrumentation, calibration methods, and typical applications. An example is discussed in detail. In addition, the use of conductivity in both online concentration monitoring and deionized water purity monitoring is discussed.

New methods are presented for coloring aramid-fiber-based materials at chemical plants, textile finishing plants, chemical cleaning plants, and industrial laundries. The article describes ways of using mathematical modeling to optimize finishing operations with allowance for specific features of the functional properties of individual batches of fibrous materials.

[EN] Fouling accumulated on reverse osmosis (RO) membranes during operation is one of the main problems affecting seawater desalination processes. This phenomenon causes a deterioration of the permselective properties of the membranes, which turns into a loss of performance of the process and costs increase. Conventionally, recovery of the process performance in desalination plants is carried out periodically by means of physical and chemical cleaning stages. However, conventional cleaning does not manage to recover completely the membrane properties and eventually can damage the membrane materials. New membrane cleaning techniques have been developed in order to improve this recovery. Ultrasound (US) radiation, which has shown to be an interesting technique during filtration since it avoids fouling deposition and allows to lengthen the period between cleaning stages, is proposed as an alternative technique to remove membrane fouling. This work investigates the effect of the combination of chemical cleaning methods and US application to clean a RO membrane from a desalination plant. The experiments performed were able to determine the best operating conditions to carry out the US cleaning protocol. Sodium hydroxide 2% w/v and sodium dodecyl sulphate 4% w/v solutions at 25 degrees C were used, as they showed the highest recovery of the membrane properties in the chemical cleaning tests. Results showed that cleaning by US had a positive effect on the membrane selectivity (increase by 15.2%), and a low significant effect on its permeability. The utilization of the chemical cleaning combined with US improved the permeate flux considerably, without modifying salt rejection index in a significant way. Among the two cleaning solutions tested, the best results in terms of permeability and selectivity of the cleaned membrane, were those obtained by the US procedure using NaOH 2% w/v cleaning solution at 25 degrees C., The authors wish to thank Abengoa Water, S.L. for the financial support given to this research, through the project "Cleaning and re-use of reverse osmosis membranes in desalination plants", which belongs to the CENIT-Tecoagua research project, funded as well by the Spanish Ministry of Science and Innovation.

In order to increase the resource of power metal optics, the features of the choice of solvents for its physical and chemical cleaning are investigated. During cleaning, on the contaminated surface there remain visually observed white film of alkali and alkaline earth metal salts, insoluble by this class of solvents, and iridescent bands from the interaction of hydrocarbons with metal, and this degrades optical properties and reduces the life of mirrors. It is demonstrated that, with the use of solvents, it is necessary to inhibit the interaction of hydrocarbons with mirrors by the stabilization of solvents or by selection of cleaning regimes.

Generally, installed piping should be cleaned in place after hydrostatic testing has been completed. The systems should also be checked for leaks, prior to cleaning by chemicals. This chapter covers the minimum requirements for Internal Chemical Cleaning of Piping Systems on the upstream side of process machineries and lube oil/seal oil systems for which removal of rust, mill scale, grease, and foreign matter is essential.

The use of lubricating oil free from detrimental contaminants enhances reliable operation of prime-movers. Flushing oil may be of the same grade as the normal lube oil. Temporary fine mesh screens are installed to ensure successful oil flushing. Flushing oil flow must be turbulent. Circulation of flushing oil is continuous with stopping from time to time for inspection and cleaning of temporary strainers. Oil lines are pounded during oil flushing to initiate vibration and thermal shock, facilitating dislodge of debris, rust, weld beads, and other loose materials inside piping. Duration of oil flushing may range from 12 h to as much as several days to reach the desired level of cleanliness. Clean oil conforms to the NAS Class 8 (ISO 4406 19/17/14) specification with moisture content of 100 mg kg − 1 .

This paper reviews current knowledge and recent advances in methods of graffiti removal. Three approaches were considered: chemical, physical (including laser) and biological. Findings concerning the efficiency and effectiveness of the methods, including any damage to the substrate or other side effects, are described. Emphasis is placed on the limitations of the reported methods. Finally, current trends and improvements in graffiti removal methods towards the use of more efficient and less damaging treatments are addressed.

To coat with much of lubricating grease is an effective approach to slow down the wearing and rusting trend of each mechanism, the lubricating grease must be removed before grease-change maintenance and overhauling of the artillery. At present, the grease removing methods mainly include physical heating, mechanical removal, chemical cleaning, etc. Comparing the advantages and disadvantages of various methods, this paper proposes to use the technology of a high-pressure water jet cleaning. This method overcomes the problems in the process of grease removal.

Membrane fouling is one of the most important considerations in the design and operation of membrane systems as it affects pretreatment needs, cleaning requirements, operating conditions, cost and performance. Given that membrane fouling represents the main limitation to membrane process operation, it is unsurprising that the majority of membrane material and process research and development conducted is dedicated to its characterization and amelioration. This work presents the fundamentals of fouling issues in membrane separations, with specific regard to membrane fouling in Membrane Bioreactors (MBRs) and the most frequently applied preventive-control strategies. Feed pretreatment, physical and chemical cleaning protocols, optimal operation of MBR process and membrane surface modification are presented and discussed in detail. Membrane fouling is the major obstacle to the widespread application of the MBR technology and, therefore, fouling preventive-control strategies is a hot issue that strongly concerns not only the scientific community, but industry as well.

Research in cleaning procedures of reverse osmosis membranes used in seawater desalination to minimize costs and achieve high efficiency is necessary. Multi-step cleaning can represent a useful tool, since the cleaning efficiency can be improved by means of utilization of different chemicals with complementary cleaning mechanisms. The objective of this work was the optimization of a two-step cleaning procedure to recover the membrane properties and reduce power costs. Spent Hydranautics SWC3 membranes (USA) were supplied by a desalination plant. Cleaning tests were performed in three stages: one-step static cleaning, two-step static cleaning and characterization of the membrane surface after the cleaning process. Four cleaning agents at two different concentrations were used. All possible combinations of them were considered, including sequence effect. After the cleaning process, membrane surface was characterized by field emission scanning electron microscopy coupled with energy dispersive X-ray spectroscopy and atomic force microscopy. One-step static cleaning test indicated that sodium dodecyl sulphate 1% w/v was the most efficient cleaning solution, followed by NaOH 2% w/v. Two-step cleaning tests showed that the procedure that maximized permeate flux recovery was surfactant-alkaline cleaning, whereas the one that maximized the recovery of the salt rejection index was alkaline-acid sequence. Characterization of the membrane surface after the cleaning steps confirmed that fouling deposits were significantly removed., The authors wish to thank Abengoa Water, S.L. for the financial support given to this research through the project "Cleaning and re-use of reverse osmosis membranes in desalination plants", which belongs to the CENIT-Tecoagua research project, funded by the Spanish Ministry of Science and Innovation. The authors would like to gratefully acknowledge Vicente Fornes and Rosa Torrero from the CSIC-I.T.Q research centre from the Universitat Politecnica de Valencia for their support given in the ATR-FTIR analysis.

The method of residential waste and food waste collecting is changed into automatic waste collection(AWC) system from direct collection by human resource. To solve the problem caused by odour from AWC facilities, the structure of input facilities, conveying pipes and collecting facilities have been changed into closed and sealed construction to enclosed the facilities and collect odour efficiently. Based on cases and experiences, to treat variable odour matters which are caused by food waste, chemical cleaning method is preferable method to cope with odour caused by food waste.

Lateral canals establish connection between the main root canal and periodontal ligament. The necrotic tissues and bacteria residing in the lateral canals are difficult to remove by mechanical and chemical cleaning and this influences filling the root canal efficiently and the outcome of the root canal therapy. The aim of this study was to evaluate the filling of artificially prepared lateral canals using six different gutta-percha obturation techniques. For this study, sixty extracted human single rooted teeth were used. Root canals were cleaned and shaped by step back technique. Six lateral canals were prepared in the coronal, middle and apical thirds in each root using #15 engine driven reamer. The teeth were randomly divided into six groups of 10 and obturated by lateral condensation, Microseal (Tycom,USA), JS Quick-Fill (JS Dental Mfg. Inc., USA), Softcore (CMS-Dental Aps., Denmark), System B (SybronEndo, USA) with Obtura II (Obtura Corp.,USA), and Thermafil (Tulsa Dental, USA) techniques using Kerr Pulp Canal sealer (Kerr Manufacturing Co, USA). Radiographs of the obturated canals were taken mesiodistally and scored according to the extension of filling of lateral canals. Roots in Thermafil group showed the greater number of filled lateral canals followed by System B/Obtura, lateral condensation, Microseal, Quick-Fill, Softcore techniques. The groups obturated with Thermafil and System B/Obtura were able to fill larger number of lateral canals than the groups obturated using the other techniques statistically (p 0.05). The number of filled lateral canals located in the middle thirds of the roots were significantly higher than the filled canals in the apical and coronal third of the canals. Thermafil and System B/Obtura techniques found to be superior to other techniques in filling lateral canals.

In this study a total of 12 coal sample was collected. 7 of these samples are local coal samples and 5 of them is exported coals. These coals samples were fractionated into two size groups, i.e. -10+3.15, -3.15+05. Float and sink analysis was performed on this two size groups of samples with Ca(NO3)2 medium at the density of 1.50 g/cm3. Latter within the scope of this study, chemical cleaning was employed on this samples. Chemical cleaning on coal samples was carried out with acids (HF and HNO3) at specific conditions. Samples have different calorific values after physical and chemical cleaning. Although some impurities have been removed with both cleaning methods, physical cleaning resulted in higher ash content coals at the end while with chemical cleaning almost no ash content coals were obtained. However, it was observed the fact that chemical cleaning resulted lower calorific values of samples. This might be because of chemical cleaning results in the decomposition of the coal matrix structure.

The possibility of application of a semipermeable polymer membrane in total with the method of rectification purification for the repeated use of freon-114 B 2 and detergent compositions based on it for cleaning metal optics in a closed technological cycle while ensuring the environmental cleanliness of the process and saving solvents has been identified and justified. The investigated adsorption method is effective for cleaning freon-114 B 2 from rosin resins contaminats: among adsorbents (activated carbon, silica gel, anion exchange resin IA-I, silica gel S-80). Silica gel S-80 has the highest adsorption capacity (up to 50 mg / l). It has been shown that regeneration of freon-114 B 2 with the help of a polymer semipermeable membrane after its use for cleaning metal optics allows to reduce the amount of impurities present in it by at least 2 orders of magnitude. Moreover, organic molecules, that have long surfactant chains, oils, fats of organic and mineral origin are almost completely separated from the regenerated solvent.

Membrane cleaning is crucial to maintain the permeability and selectivity of membranes. Physical cleaning can mitigate membrane fouling, lower the frequency of chemical cleaning, thus prolong membrane lifetime, and reduce operational costs. Backpulsing is a promising physical cleaning method, which can effectively mitigate external and non-adhesive fouling and has been used in many industrial fields. However, a comprehensive understanding of backpulsing and the optimization of this technology is still lacking. This paper critically reviews the development of backpulsing technique in microfiltration (MF) and ultrafiltration (UF) processes. Firstly, the fundamentals of backpulsing are addressed. Secondly, applications of backpulsing are summarized according to the applied fields. Results of pilot- and commercial-scale operations are presented. Moreover, factors influencing backpulsing efficiency are illustrated, including feed properties, membrane properties and operating parameters. Furthermore, mathematical models of backpulsing are overviewed. The models not only predict membrane productivity, but also provide a perspective to evaluate the performance of backpulsing in fouling mitigation. Finally, the existing challenges and future outlook are discussed.

Ceramic membrane technique was a new and efficient technology for wastewater treatment and used more and more widely in recent years. Controlling membrane fouling was the key method to ensure the efficient and stable operation of ceramic membrane. In this paper, the causes, influencing factors and control methods of ceramic membrane fouling were summarized. As one of the most effective means to control membrane fouling, several common membrane cleaning methods, such as physical cleaning, chemical cleaning, ultrasonic cleaning and combined cleaning, were introduced. And the application of ceramic membrane cleaning was presented too. Then the future directions for ceramic membrane techniquresearching was prospected.

Remanufacturing Cleaning is an important process during the remanufacturing engineering, which is unique and significantly different from the manufacturing process and has an important effect on ensuring the quality of remanufactured product. The cleanliness it achieved is an important quality index of remanufactured products, which directly affects the surface analysis, surface inspection, remanufacturing processing and assembly process and further affects the quality and cost of remanufactured products. First of all, this paper gives a systematic induction and summary on the cleaning techniques and methods of remanufacturing processes such as high-pressure water jet cleaning, ultrasonic cleaning and chemical cleaning. At the same time, the paper carries out a comparative analysis on merits and demerits of each cleaning technology. Secondly taking the remanufacturing cleaning of concrete pump truck for an example, this thesis emphasizes on introducing the cleaning techniques of pump truck vehicle cleaning and parts cleaning after dismantling, and then analysis the deficiencies of concrete pump truck cleaning from the perspective of resource and environment attribute. Finally, the paper gives development trend and prospect for the remanufacturing cleaning technology of concrete pump truck.

OPR-1000 CE Steam Generator, of which tube material is composed of Alloy-600 HTMA in nuclear power plant, secondary side is generated ODSCC(Outside Diameter Stress Corrosion Cracking) due to the accumulated sludge. ODSCC is centered around the tube sheet and is being affected depending on the height of the sludge. Chemical cleaning was carried out for a top-of-the-tube sheet(TTS) of Steam Generator in order to decrease corrosive condition of the secondary side of Steam Generator tubes and suppress the occurrence of stress corrosion cracking. The amount of sludge removal was 259.2kg. The height of the accumulated sludge was reduced from 0.71 to 0.34 inches. Corrosion rate as the maximum 2.34 mils was satisfied to within EPRI (Electric Power Research Institute) recommendation(10 mils).

Saline Water Conversion Corporation is the pioneer in developing applications and operation of nanofiltration (NF) pretreatment for seawater desalination which was developed by its research arm, namely, the Saline Water Desalination Research Institute. Initial work on a pilot plant scale, resulted in its application in one of the commercial seawater reverse osmosis (SWRO) plants at Ummlujj currently in operation since September 2000. During this long term of operation of NF–SWRO system, a number of improvements were made on the system operation based on operational experiences as well as research, which ultimately resulted in smooth operation of the same. This long-term operation revealed that it is possible to operate NF at 65% recovery at pH = 6 utilizing only low feed pressure of

The main objective of successful endodontic therapy is thorough mechanical shaping and chemical cleaning of the entire root canal system followed by three-dimensional obturation. Variation of the root canal morphology especially in multirooted teeth is a constant challenge for diagnosis and successful endodontic therapy. Mandibular molars can have an additional root located lingually (the radix entomolaris) or buccally (the radix paramolaris). An awareness and understanding of presence of additional root and unusual root canal morphology is essential as it determines the successful outcome of endodontic treatment. The present article focuses on the identification, access cavity modification and contemporary management of the distolingual root of mandibular 1st molars. How to cite this article Pawar AM, Kokate SR, Hegde VR. Contemporary Approach in Successful Endodontic Intervention in ‘Radix Entomolaris’. World J Dent 2013;4(3):208-213.

The aim of this paper is to describe cleaning processes of rotating machines in detail and to analyze the effect of chemical cleaning detergents on condition of the insulation system of the electrical rotating machines. The study emphasizes the importance of cleaning procedure as a part of the maintenance of electrical rotating machines. Three chemical solutions which contain different types of isoalkanes and acetone cleaner were investigated. The real stator windings were used for this investigation. The changes of surface resistivity were measured in initial conditions and also after long-term exposure of chemical solutions at predetermined intervals. A nonlinear regression model was defined in order to describe changes of surface resistivity during this investigation.