Indoor Formaldehyde Removal Techniques through Paints: Review

Due to its ability to cause illnesses and discomfort even at low concentrations, formaldehyde pollution of indoor air poses a significant risk to human health. Sources of formaldehyde in indoor environments include textiles, paints, wallpapers, glues, adhesives, varnishes, and lacquers;furniture and wooden products like particleboard, plywood, and medium-density fiberboard that contain formaldehyde-based resins;shoe products;cosmetics;electronic devices;and other consumer goods like paper products and insecticides. According to the World Health Organisation, indoor formaldehyde concentrations shouldn’t exceed 0.1 mg/m3. The methods include membrane separation, plasma, photocatalytic decomposition, physisorption, chemisorption, biological and botanical filtration, and catalytic oxidation. Materials based on metal oxides and supported noble metals work as oxidation catalysts. Consequently, a paint that passively eliminates aldehydes from buildings can be developed by adding absorbents and formaldehyde scavengers to the latex composition. It will be crucial to develop techniques for the careful detection and removal of formaldehyde in the future. Additionally, microbial decomposition is less expensive and produces fewer pollutants. The main goal of future research will be to develop a biological air quality control system that will boost the effectiveness of formaldehyde elimination. The various methods of removing formaldehyde through paints have been reviewed here, including the use of mixed metal oxides, formaldehyde-absorbing emulsions, nano titanium dioxide, catalytic oxidation, and aromatic formaldehyde abating materials that can improve indoor air quality.

Fabrication of SPES/Nano-TiO_2 Composite Ultrafiltration Membrane and Its Anti-fouling Mechanism

Membrane fouling is one of the major obstacles for reaching a high flux over a prolonged period of ultrafiltration（UF）process.In this study,a sulfonated-polyethersulfone（SPES）/nano-TiO2 composite UF membrane with good anti-fouling performance was fabricated by phase inversion and self-assembly methods.The TiO2 nanoparticle self-assembly on the SPES membrane surface was confirmed by X-ray photoelectron spectroscopy （XPS）and FT-IR spectrometer.The morphology and hydrophilicity were characterized by scanning electron microscopy（SEM）,atomic force microscopy（AFM）and contact angle goniometer,respectively.The anti-fouling mechanism of composite UF membrane was discussed through the analysis of the micro-structure and component of UF membrane surface.The results showed that the TiO2 content and the micro-structure of the composite UF membrane surface had great influence on the separation and anti-fouling performance.

Measurements of Formaldehyde and TVOC Emission from Paints and Coating Materials using Small Chamber Method for Building Composites

An optimal test method for paint is proposed; additionally, the Field and Laboratory Emission Cell （FLEC） method used in Europe is applied as a substitute for the 20 L small chamber method. The emission factors of total volatile organic compounds （TVOC） and formaldehyde from oil-based paint, emulsion paint, and water-dispersion paint with a coating weight of 300 g/m2, cured for 24/48 hours, were measured using the 20 L small chamber method. The emission rate of TVOC and formaldehyde from all paints began to stabilize after approximately 7 days after 24/48 hours of curing even though Korean standards stipulate that paint should be measured and analyzed after the third day of application. The emission factor of TVOC and formaldehyde from oil-based, emulsion, and water-dispersion paints were also measured using the FLEC method. There was good correlation between the 20 L small chamber method and the FLEC method for oil-based, emulsion, and water-dispersion paint emissions. With the FLEC method, using paints prepared under identical conditions, the emission rate was stable 24 hours after installation of samples because the air flow rate of FLEC is much higher than that of a 20 L small chamber, and the relative cell volume of FLEC is much smaller than that of a 20 L small chamber.

Fabrication of magnetically responsive anti-fouling and easy-cleaning nanofiber membrane and its application for efficient oil-water emulsion separation

The magnetically responsive anti-fouling nanofiber membrane(MRANM)was fabricated for efficient oilwater emulsion separation,which could be cleaned using oscillating magnetic field.MRANM was prepared by grafting superparamagnetic Fe_(3)O_(4) nanoparticles onto the surface of electrospun polyacrylonitrile nanofiber membrane(PANM).Compared with PANM,the water contact angle of MRANM decreased from 104°to 0°,indicating that the hydrophilicity of the membrane was significantly improved.For the emulsions of hexadecane,octane and rapeseed oil,the separation efficiency was 98.04%,96.59%and 92.67%,respectively.After the treatments in oscillating magnetic field,the separation efficiency kept above 95%after 8 times recycling,which indicated that the MRANM had good regenerability and reusability.The as-fabricated membrane with magnetic responsiveness facilitated an effective method for solving the membrane fouling problem during practical applications of separation high viscosity oil-water emulsion.

Porous polybenzimidazole membranes with positive charges enable an excellent anti-fouling ability for vanadium-methylene blue flow battery

A cost-effective, high-performance and highly stable membrane has always been in intensively needed in aqueous organic-based flow batteries. Here we present a porous polybenzimidazole(PBI) membrane with positive charges that endow the membrane with a high rejection and an excellent anti-fouling ability for target organic molecule and asymmetric structure that affords a high conductivity for vanadiummethylene blue flow battery(V-MB FB). The morphologies and thickness of separating layer in particular of the porous PBI can be well adjusted by simply altering the polymer concentration in the cast solution and further afford the membrane with a controllable property in terms of both ion selectivity and ion conductivity. As a result, a V-MB FB assembled with a porous PBI membrane delivers a coulombic efficiency(CE) of 99.45% and an energy efficiency(EE) of 86.10% at a current density of 40 mA cm^(-2), which is 12% higher than that afforded by a Nafion 212 membrane. Most importantly, the V-MB FB demonstrates a methylene blue(MB) utilization of 97.55% at a theoretical capacity of 32.16 Ah L^(-1)(based on the concentration of MB in the electrolyte) because of the high ion conductivity of the membrane, which favors reducing the cost of a battery. The results suggest that the designed porous PBI membranes exhibit a very promising prospect for methylene blue-vanadium flow battery.

Electromagnetic anti-fouling technology for prevention of scale

An electromagnetic anti-fouling technology(EAFT) was developed further. The operating principle of the EAFT was presented using fundamental physics laws. To validate the effect of EAFT and identify the mechanism, a circulating flow setup was built. A series of fouling tests were carried out with and without EAFT, measuring fouling thermal resistance as function of time, making scanning electron microscope images and analyzing the particles size distribution in solution by dynamics light scattering technology. The main results were as follows: 1) All the precipitated crystals in solution were calcite and there were little differences between with EAFT and without EAFT in the experimental range. 2) The number of precipitate nucleation in solution was small and the particle growth was slow without EAFT. In opposition to the case untreated, a rapid particle growth was observed and the number of nucleation was expected to be large, due to the fact that the EAFT effectively increases the ions and crystals collision frequency and effectiveness by utilizing the induced electric field. It is indicated that the particle growth is promoted mainly by coagulation process but not nucleation growth. 3) The EAFT could prolong the delay time of fouling greatly, and after the delay time, the thermal resistance quickly increased. Therefore, in order to mitigate scale significantly, the floccules in solution should be deposited beforehand in a low-lying area of the exchangers and let off in time.

Numerical Study on the Hydrodynamic Performance of Antifouling Paints

This study presents a simple numerical method that can be used to evaluate the hydrodynamic performances of antifouling paints.Steady Reynolds-averaged Navier-Stokes equations were solved through a finite volume technique,whereas roughness was modeled with experimentally determined roughness functions.First,the methodology was validated with previous experimental studies with a flat plate.Second,flow around the Kriso Container Ship was examined.Lastly,full-scale results were predicted using Granville’s similarity law.Results indicated that roughness has a similar effect on the viscous pressure resistance and frictional resistance around a Reynolds number of 10^7.Moreover,the increase in frictional resistance due to roughness was calculated to be approximately 3%-5%at the ship scale depending on the paint.

The Impact of Implementing the International Convention on the Control of Harmful Anti-fouling Systems in Ships （AFS Convention） on the Marine Environment

Marine fouling is the settlement and growth of a variety of marine organisms, such as bacteria, diatoms, protozoa and algae spores on structures immersed in seawater, such as ship＇s hulls, navigation buoys, and sonar equipment. Anti-fouling refers to material or systems used to prevent the accumulation of biological material on submerged surfaces. Bio-fouling results in higher fuel consumption and can also facilitate the transport of harmful NIS （Non-Indigenous Species）. Antifouling technologies incorporating biocides （e.g., Tributyltin） have been developed to prevent fouling. Their widespread use, however, raised concerns about their toxic effects on marine communities. The AFS Convention （International Convention on the Control of Harmful Anti-fouling Systems in Ships） is a 2001 IMO （International Maritime Organization） treaty, whereby states agree to ban the use of harmful anti-fouling paints and other anti-fouling systems that contain harmful substances. Particularly, the use of the organotinTributyltin is prohibited, since leaching of that chemical from the hulls of ships has been shown to cause deleterious effects on some sea creatures. Although the AFS Convention has entered into force, its full implementation has not yet been appropriately achieved. Most of the ratifying States have delegated the Classification Society to inspect their ships to ensure the implementation of the provisions of the Convention. Since painting ships takes place in dry docks, the full control falls in the hands of Classification Societies.

Performance of Local Clay-Titanium Dioxide Core-Shell Extender Pigments in Alkyd Paints

The performance of local clay-titanium dioxide core-shell extender pigments in alkyd paints has been studied. The physico-mechanical properties of the prepared alkyd paints were evaluated according to ASTM measurements. The effects of various environmental and corrosive factors on the paints were also studied. The study showed that the alkyd paint samples formulated using the core-shell pigments generally had low specific gravity (1.30 – 1.38), an indication that more of the core-shell pigments can be incorporated into the alkyd paints with considerable cost savings. The dry film thicknesses of the paint samples falls within 0.24 - 0.39 mm, suggesting that the samples will perform well as anticorrosive coatings and their adhesion properties are generally good, showing that they can withstand abrasive and corrosive agents. The core-shell extender pigments formulated paint samples were observed to exhibit the best dust-free, tack-free, and through dry times compared to TiO2 paint formulation. The formulated paint samples generally performed well on exposure to rain and sunlight as well as in distilled water, 2% Na2CO3, and 2% H2SO4 with only TiO2 paint formulation exhibiting rust. The good paint performance characteristics obtainable with the core-shell extender pigments are enough evidence to justify their utilization in the surface coatings industry. The performances of these core-shell extender pigments in alkyd paints have shown that they combine the properties of both the clays and titanium dioxide, and have the potential to overcome their disadvantages.

Comparative Toxicity of “Tin Free” Self-Polishing Copolymer Antifouling Paints and Their Inhibitory Effects on Larval Development of a Non-Target Organism

Toxic substances released as a result of leaching from painted surfaces to the aquatic environment affect both fouling organisms and “non-target” biota. Artemia fransiscana nauplii have been considered a useful test system for the examination of toxicity for antifouling paints. In this study, we examined the effect of four “tin free” self-polishing copolymer (SPC) antifouling paints on the larval development of Artemia nauplii. Based on the L(S/V)50 values the order of toxicity of the antifouling paints was: ANTI F > SHARKSKIN > OCEAN T/F > MICRON. Furthermore, the body size of Artemia nauplii was significantly affected at lethal and above lethal L(S/V)5024h values. The body size of 48 h-aged nauplii exposed for the last 24 hours to each of the four SPC antifouling paints was significantly lower than that of the 48 h-aged controls (0.88 ± 0.030 mm). In addition, the body size of 72 h-aged nauplii maintained for the last 24 hours to pure synthetic seawater after exposure for 24 hours to each of the four SPC antifouling paints was significantly lower than that of the 72 h-aged controls (0.96 ±0.027 mm). Overall, the SPCs examined here were substantially toxic to Artemia nauplii, but with different toxicities and modes of action, as a result of the synergistic action of distinct components of the antifouling paints.

Respiratory Sensitization &Sickness from Welding/Burning Isocyanate Containing Paints

The purpose of this paper is to make the environmental and occupational health community aware of a serious health risk associated with the common practice of burning industrial paint off of metal surfaces during or prior to welding. On four occasions bystanders and welder/burner personnel have experienced illness as a result of being exposed to the combustion products of isocyanate paints that were being burned off metal surfaces. In each case, the burning and the exposed people were outside in an open environment where the health risk was thought to be minimal due to the open environment with nominal wind movement through the work area. In one case, the person (a burner) developed permanent sensitization to phthalic anhydride as a result of the exposure. Phthalic anhydride was determined to be decomposition product of burned isocyanate paint. In the other three cases (which involved very short exposures), between two and six people became ill but did not develop sensitization. Their symptoms included dizziness, nausea, headache, and breathing difficulty the severity of which varied from very uncomfortable to temporarily incapacitating. This paper discusses the circumstances associated with each event, the approach used to determine that phthalic anhydride was a decomposition product, and some practical things that can be done to avoid having employees become victims of exposure.

Determination of Water Content of Water-soluble Paints by Gas Chromatography

This paper describes the determination of water content of water-soluble paints by gas chromatography. The water in paints is extracted by dimethyl formamide (DMF) as a solvent.Isopropanol is used as an internal standard. The mixture is separated by low-speed centrifugation.Then a 1-uL sample of the supernatant from the prepared solution is injected into the gas chromatograph. The water content is determined by internal standard calibration curve. The rate of recovery of added standard of this method is more than 98%. Relative mean deviation is less than 3‰.The linearity of calibration curve is good and relativity coefficient is higher than 0.998.

Enzyme-Containing Paints Inhibit the Growth of Marine Microorganisms

A new strategy to prevent the biofouling of water-submerged surfaces is presented here. In particular, the authors showthat carbonic anydrase from Methanosarcina thermophila can be entrapped into polyacrylic paints, preserving enzyme activity. In addition, the authors also show that enzyme-containing paints inhibit the growth of marine microorganims, preventing biofouling.

Hard Work Paints Bright Backdrop for a Young Life-Moments of President Xi Jinping with Young Chinese

COMPARING the realization of the national rejuvenation to a relay race, Chinese Presi-dent Xi Jinping called on China’s young generation to strive their best to help realize the Chinese Dream at a ceremony marking the centenary of the Communist Youth League of China(CYLC) in Beijing on May 10. Xi, also general secretary of the Communist Party of China (CPC) Central Committee and chairman of the Central Military Commission, remarked that a nation that places high hopes on its youth and maintains its youthful vigor can prosper.

De Novo Synthesis of Biopaint Using Transformed Bacteria: Analysis of Spectral Intensity Trends and Comparison to Commercial Paint

Background: Commercial paint pigments contain toxic heavy metals that harm humans and pollute the environment. To mitigate these harms, ecologically safe pigments are necessary. Objective: This experiment aims to create a biopaint de-novo using transformed Escherichia coli bacteria and compare it to commercial paint. Methods: Genetically engineered E. coli bacteria producing magenta pigment were grown in petri dishes. The pigment protein was extracted, filtered, and dehydrated into a crystalline powder. This was mixed with acrylic medium to make biopaint. The biopaint and commercial paint were applied on acrylic paper;red, green, blue, and total spectral intensities were measured daily under different testing conditions. Spectral intensity variability was measured and compared using the Coefficient of Variation (CV). Trends in spectral intensity were analyzed using regression analysis. Results: The differences in the CV of biopaint to commercial paint were less than 20% under all testing conditions. Spectral intensities for both biopaint and commercial paint did not show any significant change during the testing period under the conditions of room temperature, heat, and humidity. However, under the cold testing condition, biopaint showed a slight but statistically significant (p-value Conclusion: This experiment proves that E. coli-derived pigments can be used to make biopaint which has a similar durability to commercial paint as measured by the spectral intensities.

TV DirectorWho Paints Chinese History with Cameras

THE large-scale TV program, Gems of the Country, has had several airings on prime time CCTV, and has been warmly received each time, winning the unanimous praise of viewers. The program actively promotes Chinese national culture, boosting national morale, and bringing the splendid culture of China to the world.The initiator, chief planner and chief director of this program is Li Dongge, a graduate of the Xi’an University of

Investigation of the Film Formation in Dynamic Air Spray Painting

To accurately predict the film thickness distribution during dynamic spraying performed with air guns and support accordingly the development of intelligent spray painting,the spray problem was analyzed numerically.In particular,the Eulerian-Eulerian approach was employed to calculate the paint atomization and film deposition process.Different spray heights,spray angles,spray gun movement speeds,spray trajectory curvature radii,and air pressure values were considered.Numerical simulation results indicate that the angle of spray painting significantly affects the velocity of droplets near the spray surface.With an increase in the spraying angle,spraying height and spray gun movement speed,the maximum film thickness decreases to varying degrees,and the uniformity of the film thickness also continuously worsens.When the spray gun moves along an arc trajectory,at smaller arc radii,the film thickness on the inside of the arc is slightly greater than that on the outside,but the impact on the maximum film thickness is minimal.Increasing air pressure expands the coating coverage area,results in finer atomization of paint droplets,and leads to a thinner and a more uniform paint film.However,if the pressure is too high,it can cause paint splattering.Using the orthogonal experimental method,multiple sets of simulation calculations were conducted,and the combined effects of spraying height,spray angle,and spray gun movement speed on the film thickness distribution were comprehensively analyzed to determine optimal configurations.Finally,the reliability of the numerical simulations was validated through dynamic spray painting experiments.

Intergeneric chromosome-specific painting reveals differential chromosomal transmission from Tripidium arundinaceum in sugarcane progeny

Sugarcane has recently attracted increasing attention for its potential as a source of sugar and bioethanol,so increasing its yield is essential to ensure the sugar security and bioenergy production.Intergeneric hybridization is a highly efficient method to produce new genetic variants of crop plants,particularly those species with high ploidy such as sugarcane(Saccharum spp.).Tripidium arundinaceum exhibits many desirable agronomic traits,and has been widely studied to produce hybrids with improved stress tolerance and other characteristics in sugarcane breeding.However,the genetic relationship between T.arundinaceum and Saccharum species,and the individual T.arundinaceum chromosomal compositions in sugarcane hybrids are still elusive.Here we used whole-genome single-nucleotide polymorphisms(SNPs)to ascertain the phylogenetic relationships between these species and found that T.arundinaceum is more closely related to Saccharum than Sorghum,in contrast to the previous narrow genetic analyses using chloroplast DNA.Additionally,oligonucleotide(oligo)-based chromosome-specific painting derived from Saccharum officinarum was able to distinctly identify the chromosomes of T.arundinaceum.We developed the oligo-genomic in situ hybridization(GISH)system for the first time,to unveil the novel chromosome translocations and the transmission of individual T.arundinaceum chromosomes in sugarcane progeny.Notably,we discovered that the chromosomal transmission of T.arundinaceum exhibited several different inheritance modes,including n,2n,and over 2n in the BC1 progenies.Such inheritance patterns may have resulted from first division restitution(FDR)or FDR+nondisjunction of a chromosome with the sister chromatids in the second meiosis division/second division restitution(FDR+NSC/SDR)model during meiosis.These results will be of substantial benefit for the further selection of T.arundinaceum chromosomes for sugarcane genetic improvement.

Co-pyrolysis of Sewage Sludge with Paint Sludge: Kinetics and Thermodynamic Analysis via Iso-conversional Methods

This study explored the synergistic interaction of sewage sludge(SS)and automotive paint sludge(PS)during co-pyrolysis for the optimized treatment of sewage sludge in cement kiln systems,utilizing thermogravimetric analysis(TGA)and thermogravimetric-mass spectrometry(TGA-MS).The result reveals the coexisting synergistic and antagonistic effects in the co-pyrolysis of SS/PS.The synergistic effect arises from hydrogen free radicals in SS and catalytic components in PS,while the main source of the antagonistic effect is that,during the mechanical mixing process,the SS/PS is converted from the particulate form into a dough-like rubbery which contributes to the film-forming effect,hindering the volatilization of volatile components.SS/PS co-pyrolysis reduces the yielding of tar production while increasing coke and gas.This study will provide some in-depth insights into the co-pyrolysis of SS/PS,and offer theoretical support for the subsequent research on the collaborative disposal processes in cement kilns.

Improved Scatter Search Algorithm for Multi-skilled Personnel Scheduling of Ship Block Painting

This paper focuses on the optimization method for multi-skilled painting personnel scheduling.The budget working time analysis is carried out considering the influence of operating area,difficulty of spraying area,multi-skilled workers,and worker’s efficiency,then a mathematical model is established to minimize the completion time. The constraints of task priority,paint preparation,pump management,and neighbor avoidance in the ship block painting production are considered. Based on this model,an improved scatter search(ISS)algorithm is designed,and the hybrid approximate dynamic programming(ADP)algorithm is used to improve search efficiency. In addition,the two solution combination methods of path-relinking and task sequence combination are used to enhance the search breadth and depth. The numerical experimental results show that ISS has a significant advantage in solving efficiency compared with the solver in small scale instances;Compared with the scatter search algorithm and genetic algorithm,ISS can stably improve the solution quality. Verified by the production example,ISS effectively shortens the total completion time of the production,which is suitable for scheduling problems in the actual painting production of the shipyard.