Self-cleaning Capability Research Articles

Review of hydraulic performance of open‐channel flow‐measuring flumes

The review explored various flumes used for open channel flow measurement and provided insight into operational concepts, discharge measurement, range of flow, head loss requirements, degree of accuracy and submergence, advantages, and limitations for use. The reviewed flumes included; Parshall flumes, Montana flumes, Cutthroat flumes, H-flumes, Trapezoidal flumes, Replogle-Bos-Clemmens (RBC) flumes, Palmer-Bowlus flumes and Central Baffle flumes (CBF). Based on the stage and discharge relationship, the reviewed flumes have a reasonable accuracy of ± 10 % over a wide range of flows. RBC flumes are the most accurate flumes (± 2 %). For flows that deal with a lot of sediments, most flumes have self-cleaning capability except for Palmer-Bowlus flumes and Central Baffle flumes. H-flumes have low resistance to submergence. The submergence transition for H-flumes is only 25-30 %. RBC flumes and Palmer-Bowlus flumes have the highest submergence (90 %). CBF and Palmer-Bowlus flumes need to be improved in order to have self-cleaning capability. Submerged flow corrections need to be developed and published for Palmer-Bowlus flumes and RBC flumes. The reviewed flumes effectively operate with a minimal head loss. The review has provided an insight on selection of an appropriate type of flume for flow measurement in open channels.

The Effect of Polymeric Surfactant on Adhesion and Uniformity of Ag-TiO<sub>2</sub> Coating on Air Filter with Self-Cleaning Capability

This research is a continuing study on F9-filter development via Ag-TiO2 coating to promote volatile organic compounds (VOCs) removal and antibacterial activity. Problems of poor adhesion and uniform distribution of coating material on the filter surface were observed, so the addition of a polymeric surfactant (PS), which behaves as both a binder and a surfactant, was applied in this study in order to solve such problems. Dip coated F9-filter samples with a selection of Ag-TiO2 suspension were characterized and tested. Environmental scanning electron microscope was used to characterize uniform coating distribution on an air filter. Self-cleaning test was performed in accordance with ISO 27448. The results showed that Ag-TiO2 with PS dip coating on air filters provide good adhesion and high uniformity. It is also found that self-cleaning capability of Ag-TiO2 with PS coated filter is increasing with increasing of Ag-TiO2 and PS concentrations. Within a scope of this work, only visible light can drive Ag-TiO2 to undertake photocatalytic activity. Hence, improvement of Ag-TiO2 coating on F9- filter is confirmed when PS is applied.

A UV-Reflective Organic-Inorganic Tandem Structure for Efficient and Durable Daytime Radiative Cooling in Harsh Climates.

Radiative cooling shows great promise in eco-friendly space cooling due to its zero-energy consumption. For subambient cooling in hot humid subtropical/tropical climates, achieving ultrahigh solar reflectance (≥96%), durable ultraviolet (UV) resistance, and surface superhydrophobicity simultaneously is critical, which, however, is challenging for most state-of-the-art scalable polymer-based coolers. Here an organic-inorganic tandem structure is reported to address this challenge, which comprises a bottom high-refractive-index polyethersulfone (PES) cooling layer with bimodal honeycomb pores, an alumina (Al2 O3 ) nanoparticle UV reflecting layer with superhydrophobicity, and a middle UV absorption layer of titanium dioxide (TiO2 ) nanoparticles, thus providing thorough protection from UV and self-cleaning capability together with outstanding cooling performance. The PES-TiO2 -Al2 O3 cooler demonstrates a record-high solar reflectance of over 0.97 and high mid-infrared emissivity of 0.92, which can maintain their optical properties intact even after equivalent 280-day UV exposure despite the UV-sensitivity of PES. This cooler achieves a subambient cooling temperature up to 3 °C at summer noontime and 5 °C at autumn noontime without solar shading or convection cover in a subtropical coastal city, Hong Kong. This tandem structure can be extended to other polymer-based designs, offering a UV-resist but reliable radiative cooling solution in hot humid climates.

Enhanced antimony removal within lamellar nanoconfined interspaces through a self-cleaning MXene@CNF@FeOOH water purification membrane

MXenes as two dimensional nanocarriers are promising candidate materials for advanced water purification membranes. Nevertheless, the practical applications of MXene-based membranes are hindered by their poor mechanical strength and widespread fouling issue. Herein, we report a free-standing nanocomposite membrane for the adsorptive separation of antimony (Sb) species from wastewater. Cellulose nanofibrils (CNFs) are adopted as functional scaffolds to assemble with Ti3C2Tx MXenes by forming interlocked structures that significantly promote the mechanical strength and toughness of the membrane, meanwhile, the in situ anchored β-FeOOH nanorods in the nanoconfined interspaces offer abundant active sites for enhanced pollutants removal. The as-prepared MXene@CNF@FeOOH (MCF) membranes demonstrate stable and pH-independent static removal capacities for Sb species. Also, their excellent interception performances for treating Sb containing synthetic effluents are confirmed in continuous flow-through modes, presenting a rapid wastewater purification with allowable emission standards under a high feeding flux of 102.3 L m−2h−1 bar−1. More importantly, the MCF membranes exhibit unique self-cleaning capability via photo-Fenton degradation of the adsorbed organic dye by 90% within 1 h. Molecular dynamics simulations further support their superior dynamic removal performance toward Sb species. This work sheds light on designing mechanically robust MXene-based water purification membranes with favourable self-cleaning property.

Highly Transparent and Zirconia-Enhanced Sol-Gel Hybrid Coating on Polycarbonate Substrates for Self-Cleaning Applications.

To improve the efficacy of polymer-based substrate hybrid coatings, it is essential to simultaneously optimize mechanical strength and preserve the optical properties. In this study, a mixture of zirconium oxide (ZrO2) sol and methyltriethoxysilane modified silica (SiO2) sol-gel was dip-coated onto polycarbonate (PC) substrates to form zirconia-enhanced SiO2 hybrid coatings. Additionally, a solution containing 1H, 1H, 2H, and 2H-perfluorooctyl trichlorosilane (PFTS) was employed for surface modification. The results show that the ZrO2-SiO2 hybrid coating enhanced the mechanical strength and transmittance. The average transmittance of the coated PC reached up to 93.9% (400-800 nm), while the peak transmittance reached up to 95.1% at 700 nm. SEM images and AFM morphologies demonstrate that the ZrO2 and SiO2 nanoparticles were evenly distributed, and a flat coating was observed on the PC substrate. The PFTS-modified ZrO2-SiO2 hybrid coating also exhibited good hydrophobicity (WCA, 113°). As an antireflective coating on PC, with self-cleaning capability, the proposed coating has application prospects in optical lenses and automotive windows.

Performance of a superamphiphobic self-cleaning passive subambient daytime radiative cooling coating on grain and oil storage structures

The thermal performance of a novel exterior coating material for commonly used grain and food-grain oil structures was investigated. Grain structures included a concrete squat silo and a concrete warehouse while the edible oil structure was a concrete sided tank. The exterior coating provided excellent moisture runoff and solar reflectance properties and is best described as a superamphiphobic self-cleaning passive subambient daytime radiative cooling (SSC-PSDRC) coating. The coating exhibited a remarkable subambient daytime cooling effect in various structures in different climatic regions. Compared with the roof surface temperatures of a cool white-coated concrete grain silo and a gray carbon iron-based edible oil storage tank, those of the PSDRC coated top surfaces could be reduced by 37 °C and 33 °C, respectively. The roof surface temperature of a warehouse painted with a cool-white coating—with a solar reflectance of 0.9 and an emissivity of 0.85—and that of a warehouse with the roof installed with aluminised polymer waterproof membranes were 19 °C and 18 °C higher than that of the PSDRC warehouse, respectively. Consequently, the interior temperature of the wheat pile in the PSDRC grain silo was 10 °C lower than that in the control squat silo. With the inner loop flow temperature control system operating, the interior air temperatures of the PSDRC west-facing separate space were 6 °C and 3 °C higher than those of the cool-white coated and control west-facing separate spaces, respectively. Even after the application of PSDRC coating for only a few days, the interior air temperature of the PSDRC oil storage tank was reduced by 38 °C, and the interior temperature of the oil storage tank was reduced by 4 °C. Furthermore, in practical applications, the coating showed impressive superamphiphobic self-cleaning capabilities and super aging resistance. The wide applications of the coating would have far-reaching, global implications for maintaining grain and edible oil products, particularly in the sub-tropical climates.

Durable self-cleaning superhydrophobic coatings based on 5 Mg(OH)2·MgSO4·2H2O whisker-SiO2 nanoparticles composites

Poor mechanical robustness is a major handicap to the practical application of superhydrophobic coatings. It is imperative to design an effective strategy to improve the durability of superhydrophobic coatings. In this work, we prepared a robust superhydrophobic coating using all-in one suspension that contained magnesium oxysulfate whiskers, SiO2 nanoparticles and amino drying varnish via a drop coating method. The suspension was formed through that a mixture of magnesium oxysulfate whiskers and SiO2 nanoparticles modified by tetraethylorthosilicate and octadecyltrichlorosilane was mixed into amino drying varnish diluted with thinner. The results showed that such inorganic–organic composite modification method could effectively improve the modified effect. The prepared coating displayed excellent water repellency not only on the top surface but also at any exposed internal section throughout the coating, and maintained its superior superhydrophobicity even after the top area was scraped off a layer. Notably, the coating exhibited outstanding self-cleaning capability with a contact angle of 168.81° and a very low sliding angle. Further, amino drying varnish as binders replaced by other common commercial paints could also prepare superhydrophobic coatings. This study can not only facilitate the large-scale fabrication and application of superhydrophobic coatings, but also expand the application filed of magnesium oxysulfate whiskers.

Robust UV-curable anti-smudge electrodeposition coating for self-cleaning, anti-graffiti and corrosion protection

In this study, a UV-curable anti-smudge cathodic electrophoretic coating was developed by free radical copolymerization of various acrylic monomers using heptadecafluorodecyl acrylate (FOEA) as a functional monomer to provide a low surface energy structure to the acrylate precursor. The precursor was then grafted with the synthetic double-bond terminated IPDI-HEA on the precursor, and finally dipentaerythritol penta/hexaacrylate (5-Acl) was introduced as a crosslinker for the subsequent cathodic electrophoresis and UV-curing process. The chemical structure and surface fluorine content of the fluorinated waterborne polyacrylate (FWPA) were confirmed by 1H NMR, FT-IR, and XPS, respectively. The surface morphology and roughness of the coating were assessed using SEM and AFM instruments. The contact and sliding angles of water, diiodomethane, and hexadecane were determined. The self-cleaning capability was demonstrated by measuring the oil-based and aqueous epoxy paints, as well as carbon powder sliding on the coated tinplate surface. The anti-graffiti property was also integrated with a red marker. The resistance to strong acid, salt spray, impact, friction, and bending were characterized. All these results showed remarkable self-cleaning and anti-graffiti capabilities of the as-prepared UV-curable electrophoretic coating. Meanwhile, the coating displayed exceptional robustness in resisting chemical corrosion and mechanical damage. This newly developed UV-curable anti-smudge cathodic electrophoretic coating has great application potential in various metal protection industries.

A Simple and Convenient Method for Preparing Fluorine-Free Durable Superhydrophobic Coatings Suitable for Multiple Substrates.

Superhydrophobic coatings have attracted a lot of attention due to their excellent self-cleaning and anti-fouling capabilities. However, the preparation processes for several superhydrophobic coatings are intricate and expensive, which restricts their usefulness. In this work, we present a straightforward technique for creating durable superhydrophobic coatings that can be applied to a variety of substrates. The addition of C9 petroleum resin to a styrene-butadiene-styrene (SBS) solution lengthens the SBS backbone and undergoes a cross-linking reaction to form a dense spatial cross-linked structure, improving the storage stability, viscosity, and aging resistance of the SBS. The combined solution functions as a more stable and effective adhesive. Using a two-step spraying technique, the hydrophobic silica (SiO2) nanoparticles solution was applied to the surface to create durable nano-superhydrophobic coatings. Additionally, the coatings have excellent mechanical, chemical, and self-cleaning stability. Furthermore, the coatings have wide application prospects in the fields of water-oil separation and corrosion prevention.

Robust superhydrophobic materials with outstanding durability fabricated by epoxy adhesive-assisted facile spray method

Superhydrophobic materials are promising next-generation waterproof materials due to their excellent self-cleaning, antifouling and additional capabilities. Herein, the superhydrophobic materials with excellent comprehensive performance were developed via a simple, low-cost, environmental, and scalable spray method with epoxy adhesive assistance. The epoxy adhesive enhanced the adhesion strength between spray coating and substrates significantly. Consequently, various properties of superhydrophobic coatings were improved greatly. The as-prepared superhydrophobic surfaces exhibited excellent mechanical durability. The water contact angle maintained unchanged basically and sliding angle only increased slightly even though sandpaper abrasion distance had extended to 2100 cm or tape-peeling test had reached 30 cycles. Moreover, the strong water repellence retained even after 72 h immersion in strong acid/alkali, 1 h treatment upon 280 °C, and 7 days exposure under 254 nm UV light. These indicated that the obtained superhydrophobic materials exhibited outstanding acid, alkali, high temperature, and UV light resistance and stability. Besides, the superhydrophobic materials demonstrated excellent self-cleaning and anti-icing performance. So the synthetic superhydrophobic materials were expected to have a wide range of applications in the industrial production and daily life. More importantly, they could be applied in a variety of harsh environments for long periods of time.

Self-Healing, Robust, Liquid-Repellent Coatings Exploiting the Donor-Acceptor Self-Assembly.

Liquid-repellent coatings with rapid self-healing and strong substrate adhesion have tremendous potential for industrial applications, but their formulation is challenging. We exploit synergistic chemistry between donor-acceptor self-assembly units of polyurethane and hydrophobic metal-organic framework (MOF) nanoparticles to overcome this challenge. The nanocomposite features a nanohierarchical morphology with excellent liquid repellence. Using polyurethane as a base polymer, the incorporated donor-acceptor self-assembly enables high strength, excellent self-healing property, and strong adhesion strength on multiple substrates. The interaction mechanism of donor-acceptor self-assembly was revealed via density functional theory and infrared spectroscopy. The superhydrophobicity of polyurethane was achieved by introducing alkyl-functionalized MOF nanoparticles and post-application silanization. The combination of the self-healing polymer and nanohierarchical MOF nanoparticles results in self-cleaning capability, resistance to tape peel and high-speed liquid jet impacts, recoverable liquid repellence over a self-healed notch, and low ice adhesion up to 50 icing/deicing cycles. By exploiting the porosity of MOF nanoparticles in our nanocomposites, fluorine-free, slippery liquid-infused porous surfaces with stable, low ice adhesion strengths were also achieved by infusing silicone oil into the coatings.

Au@Ag/ultrathin g-C3N4/graphene composite surface-enhanced Raman scattering film with stable, flexible and self-cleaning capability

Flexibility and self-cleaning are the main research hot-spots in the development of plasma substrates for practical applications in Surface-enhanced Raman scattering (SERS) at present. In this study, a flexible composite Au@Ag/ultrathin g-C3N4/Graphene (AUG) film based on PDMS film was reported and used as a highly sensitive SERS substrate for the detection of rhodamine 6G (R6G) molecules. The Au@Ag nanosphere array formed by self-assembly provided dense hot-spots, the ultrathin g-C3N4 enabled the composite to possess excellent photocatalytic ability, and the graphene enhanced SERS detection and photocatalytic performance while improving the stability of the composite film. The results showed that the AUG flexible composite film had a detection limit of 10−12 M for R6G molecules. After 10 photocatalytic cycles of testing, the composite film maintained 83 % of SERS activity. Benefiting from the graphene covering the surface, the composite films showed only a 5 % decrease in SERS detection performance after 30 days of storage in air. The facile fabrication process of AUG composite film enables it to be an outstanding candidate for the flexible, inexpensive, and stable wearable SERS sensing systems.

In situ transformation of hierarchical FeOOH/CuO arrays with electro-cleaning capability for oil-in-water emulsion separation and electro-fenton degradation of organic dye

With the increasing oily wastewater discharges and crude oil leakage accidents, the eco-environment and human health is seriously harmed. Membrane technology is an ideal choice for industrial oil/water separation, but the gradually structural fouling has severely hampered the long-term practical applications. Herein, membrane separation, electroflotation and electro-Fenton technologies are successfully coupled through structural design and regulation. The FeOOH nanosheet/CuO nanowire coated on copper mesh is prepared via chemical oxidation and thermal dehydration. The FeOOH nanosheets are in situ converted and tightly encapsulated on the surface of CuO nanowires, while the hierarchical nano-array structure and interconnected FeOOH coating ensure the superhydrophilic, underwater superoleophobic and electroflotation self-cleaning capabilities. Therefore, the 3*Fe/CuO-5 membrane exhibits high water flux (≥1400 L h−1 m−2), separation efficiency (≥99.2%) and excellent electroflotation self-cleaning capability (within 2 min) in oil-in-water emulsion separation. Moreover, the heterogeneous electro-Fenton system composed of 3*Fe/CuO-5 membrane exhibits good degradation efficiency of 30 mg L−1 methylene blue within 100 min. Thus, the as-prepared 3*Fe/CuO-5 membrane is promising in industrial wastewater purification due to its rapid oil separation and soluble organic purification ability.

Non-isocyanate Polyurethane Coating with High Hardness, Superior Flexibility, and Strong Substrate Adhesion.

Flexible hard coatings with strong adhesion are critical requirements for several foldable devices and marine applications; however, only a few such coatings have been reported. Herein, we report a non-isocyanate polyurethane (NIPU) coating prepared by the epoxy-oligosiloxane nanocluster-amine curing reaction and cyclic carbonate-amine polyaddition, where the former provides the coating with ceramic-like hardness and polymer-like flexibility while the latter polymerization results in NIPU with strong substrate adhesion. The coating is transparent (>92% transmittance), hard (5-7 H), and flexible (2 mm bending diameter). It has strong adhesion to various substrates including aluminum alloy, titanium, steel, glass, ceramic, epoxy, and polyethylene terephthalate (2-8 MPa), which can be attributed to the high density of polar groups in NIPU. Moreover, we can facilely endow the coating with anti-icing, self-cleaning, and anti-smudge capabilities by incorporating amine-terminated low-surface-tension polydimethylsiloxane (PDMS) to replace a part of the amine curing agent. Particularly, the mechanical properties of NIPU coatings are only slightly affected by the introduction of low-content PDMS since it intends to enrich on the surface. The novel coating has promising future for use in fields of foldable devices and marine applications.

Self-cleaning and anti-fogging hierarchical structure arrays inspired by termite wing

Wings of the Formosan subterranean termite (Coptotermes formosanus Shiraki) covered with micrometer-scale hairs and nanometer-scale wax patches, allow them to greatly reduce adhesions to water droplets of various sizes. Inspired by the anti-wetting structures, we develop a colloidal lithography-based strategy integrated with a scalable self-assembly approach to engineer hierarchical conical structure arrays. The resulting structure arrays provided a water contact angle as high as 175.3° and a low contact angle hysteresis of 2.7° after surface modification. Importantly, the resulting superhydrophobic structures even feature distinguished self-cleaning and anti-fogging capabilities. The dependence of structure configuration on the anti-wetting functionalities is also investigated in this research.

Expired yogurt-derived, three-dimensional water evaporator with sustainable self-cleaning and high mechanical properties for the desalination and purification of oil-contaminated seawater

In this study, expired yogurt-derived three-dimensional water evaporators were developed using a freeze-drying calcination technique and applied to the desalination and purification of oil-contaminated seawater. By mixing polyvinyl alcohol and a super absorbent polymer, the maximum pressure of the expired yogurt-derived water evaporator is capable of being maintained at 2.5 MPa, which is much greater than any previously reported values. Moreover, super absorbent polymer and polyvinyl alcohol can also adjust the pyrrolic nitrogen content, thereby increasing light-to-heat efficiency by reducing the evaporation enthalpy of water. The optimized water evaporator exhibited an excellent solar evaporation rate of 3.25 kg m−2 h−1 and a high light-to-heat efficiency value of 96.47 % under one-sun irradiation. After desalination, the concentrations of Na+, K+, Mg2+, and Ca2+ ions satisfied drinking water standards. The optimized water evaporator exhibited excellent salt inhibition and antibacterial properties during the water evaporation process, resulting in a sustainable self-cleaning capability. The optimized water evaporator can purify oil-contaminated seawater because of its unique wetting characteristics and microporous structure. The expired yogurt-derived, three-dimensional water evaporator developed in this study shows great potential for the purification of oil-contaminated seawater.

Vapor-based fabrication of PEDOT coating for wearable strain sensors with excellent sensitivity and self-cleaning capability

Poly(3,4-ethylenedioxythiophene) (PEDOT) coating is advantageous in constructing flexible sensors, due to its good flexibility, high conductivity, and excellent physical and chemical stability. Traditional solution-based coating methods, however, are difficult to retain the micro- and nanostructures of the substrates, thus decreasing the sensitivity of the resulted sensors. In this work, we prepared superhydrophobic (SHB) strain sensors using a piezoresistive composite made from consecutive vapor deposition of conformal polymer coatings, i.e. PEDOT and poly(perfluorodecyl acrylate-co-ethylene glycol diacrylate) on fabrics using oxidative and initiated chemical vapor deposition methods. Compared with the pristine fabric sample, the composite materials displayed significantly improved initial currents, which are attributed to more conductive paths created by PEDOT coating. The resulted strain sensor displayed great flexibility, large sensitivity, wide sensing range, and excellent reliability. Furthermore, the sensor has been successfully employed to monitor various human motions in real time. The hydrophobic outer layer endows the sensor self-cleaning and durability capacities, indicating possible applications under harsh environment.

Techniques of Bioremediation using bacteria for the treatment of polycyclic aromatic hydrocarbons: A Review

The term "hydrocarbon" is self-explanatory and refers to solely carbon and hydrogen compounds. Hydrocarbons play an important role in our everyday lives. Hydrocarbons, particularly polycyclic aromatic hydrocarbons, harm biota. The relatively fast introduction of xenobiotic compounds, as well as the enormous movement of natural materials to various environmental compartments, can often overwhelm the self-cleaning capabilities of the recipient ecosystem, resulting in pollution and accumulation of hazardous or even lethal levels. Bacteria capable of hydrocarbon degradation are frequently used in the bioremediation of fuel oil-contaminated sites. Presently, multiple sophisticated methodologies, transcriptomics, proteomics and are effectively utilized for the depiction of hydrocarbons degrading microorganisms. These expertises are highly developed, and its integration with bioinformatics tools makes it even more efficient. Though health science and biological science are the major relevant areas for molecular docking, it has been effectively used to explore the process of bio-degradation in ecological remediation in recent years. This review focuses on the sources, fate of PAHs, human exposure, various computational aspects associated with PAHs, and some approaches of synthetic biology related to pollutant degradation and PAH‑degradation by genetically engineered microorganisms.

Agroclimatic and agroecotoxicological justification of zonal chemical protection systems against harmful organisms for field crops under conditions of climate change in Ukraine

Goal. Agroclimatic and agroecotoxicological zoning of the territory of Ukraine in order to justify ecologically safe zonal systems of chemical protection against harmful organisms, their optimization and adaptation to changes in climatic conditions and phytosanitary state of agrocenoses in different soil-climatic zones of Ukraine.
 Methods. Analytical-synthetic and experimental methods were used in the research. Literary sources, reports of the Institute of Plant Protection, data on the distribution and number of pests given in the annual reviews of the Department of Phytosanitary Safety of the State Service of Ukraine on Food Safety and Consumer Protection, databases of the State Statistic Service and the Hydrometeorological Center of Ukraine, as well as the results of field experiments were analyzed. Phytosanitary and ecotoxicological monitoring was carried out according to generally accepted methods. The degree of hazard of pesticide use was assessed using an integral 7-point scale, the risk — according to the agro-ecotoxicological index (AETI).
 Results. Ecological and statistical analysis of long-term databases, dynamics of agrometeorological indicators allows us to come to the conclusion that during the last 10 years climate changes have accelerated. They manifested through the equalization of the temperature field across the country, the increase in the sum of effective temperatures, and a deterioration of heat and moisture supply. This led to a disruption in the functioning of agrocenoses, a decrease in tolerance to the pesticide load. Under conditions of extension of the specified trends, significant disruptions in the functioning of the agricultural sector should be expected, considering the speed of changes. With the help of the Arc GIS — Arc INFO software complex, the agroclimatic and agroecotoxicological zoning of the territory of Ukraine under conditions of climatic changes of 2010—2020 was carried out. A decrease in the self-cleaning ability of the territory has been established. This is especially noticeable in the Forest Steppe, where the zonal self-cleaning index decreased from 0.70—0.50 to 0.60—0.45. Maps of agro-climatic zones and regions of Ukraine with different self-cleaning capabilities have been created.
 Conclusions. Regular addition and update of agro-climatic regulatory information under conditions of climate change is used for the correct selection and placement of agricultural areas, crops, assessment of conditions for their growth and development, planning of field work periods, forecasting of crop production in a specific year. This information is necessary for improving the culture of agriculture, increasing the production of plant products along with the wide application of modern technologies of crop cultivation, in particular chemical protection against harmful organisms.

Nanofibrous Janus membrane with improved self-cleaning property for efficient oil-in-water and water-in-oil emulsions separation

Developing a membrane integrating high separation efficiency and good anti-fouling ability for both oil-in-water and water-in-oil emulsions is meaningful due to the complexity and diversity of actual oily wastewater. Herein, a facile strategy was designed to generate a nanofibrous Janus membrane to achieve multifunctional and self-cleaning properties. Hydrophilic β-FeOOH was anchored on poly(vinylidene fluoride-co-hexa-fluoropropylene) (PVDF-HEP) fibers to achieve hydrophilicity and self-cleaning performance of PVDF-HEP/β-FeOOH layer by in situ mineralization technology. The Janus membrane was then obtained by incorporating PVDF-HEP fibers layer onto the hydrophilic layer through electrospinning technology. PVDF-HEP/β-FeOOH layer owns superhydrophilicity (WCA = 0°) and underwater superoleophobicity (OCA = 159°), which can separate different surfactant-stabilized oil-in-water emulsions with separation efficiency of above 99.8 % when this layer is facing up. Conversely, the PVDF-HEP layer exhibits superhydrophobicity (WCA = 149°), which can separate different surfactant-stabilized water-in-oil emulsions with separation efficiency of above 99 % when this layer is facing up. More importantly, a satisfying water flux recovery rate of 98.2 % is acquired due to the synergistic effect between β-FeOOH photocatalysis and asymmetric wettability of the membrane, endowing the membrane with effective self-cleaning capability and satisfactory stability. This study provides a new strategy for designing multifunctional membrane toward actual complex oily wastewater treatment.