ON THE ISSUE OF DETERMINING THE QUALITY OF FOAMING AGENTS DURING THEIR STORAGE AT FACILITIES

В статье представлены результаты анализа экспертных заключений по отчетным материалам, выполненным испытательными пожарными лабораториями ФГБУ ФПС в 2021 году по контролю качества пенообразователей и смачивателей, хранящихся в пожарных частях, на объектах, а также в установках пожаротушения. There are presented the results of analysis of expert reports on the reporting materials carried out by fire testing laboratories of FGBU FPS in 2021 concerning quality control of foaming agents and wetting agents stored in fire departments, at facilities, as well as in fire extinguishing installations.

Innovative Surfactant Chemistry Offers the Performance Advantages to Invert Emulsion Drilling Fluids While Drilling Under Challenging Environments

Stable invert emulsion with oil wet solids is achieved using invert emulsifiers and wetting agents. This paper reviews the chemistry and performance criteria of traditional invert emulsifiers and wetting agents utilized in formulating stable invert emulsion drilling fluids. However, occasionally such stable invert emulsion drilling fluids can be destabilized due to various hostile conditions encountered during drilling operation, and can adversely impact the drilling cost. Extreme preventive measures cannot avoid such hostile conditions such as sudden water influx, excessive solids and salt contaminations during drilling. Upon solids becoming extremely water wet with "flipped emulsion", it becomes impossible to fix the drilling fluid, resulting in expensive maneuver. Often situation cannot be corrected with traditional wetting agents and emulsifiers even at high level of treatments. New innovative chemistry addresses the severe water-wetting and emulsion instability of invert emulsion under extreme challenging and hostile situations. The unique water soluble oil mud conditioner (OMC) synergistically enhances the performances of traditional oil-wetting agents and emulsifiers at very low, as little as 0.5 ppb levels of treatment. This OMC improves and extends the efficacy of the traditional invert emulsifiers and oil wetting agents resulting in reduced usage of these additives with excellent economic advantages. The 15.0 ppg, invert emulsion drilling fluids were prepared using 2-3 ppb of primary and secondary emulsifiers, and these fluids were destabilized using high shear mixer for 7-8 hours. The destabilized fluids had severe water wet solids and ES value of less than 5. These destabilized fluids, upon treating with 0.5 ppb of newly developed OMC instantly became oil-wet and shiny and ES was increased to greater than 500. To demonstrate the effectiveness of OMC in pre-treatment situation, the base fluids treated with 0.5 −1.0 ppb of OMC showed superior mud stability compared to base fluid when contaminated with sea water, fine solids, barite and high salt contaminations. The OMC is flexible in its application and can be used as pre-treatment to improve the overall performance of drilling fluids and can also be used for post-treatment to recover the drilling fluids, which have been rendered unusable.

Use of Alternative Gelling Agents Reveals the Role of Rhamnolipids in Pseudomonas aeruginosa Surface Motility

Pseudomonas aeruginosa is a motile bacterium able to exhibit a social surface behaviour known as swarming motility. Swarming requires the polar flagellum of P. aeruginosa as well as the secretion of wetting agents to ease the spread across the surface. However, our knowledge on swarming is limited to observed phenotypes on agar-solidified media. To study the surface behaviour and the impact of wetting agents of P. aeruginosa on other surfaces, we assessed surface motility capabilities of the prototypical strain PA14 on semi-solid media solidified with alternative gelling agents, gellan gum and carrageenan. We found that, on these alternative surfaces, the characteristic dendritic spreading pattern of P. aeruginosa is drastically altered. One striking feature is the loss of dependence on rhamnolipids to spread effectively on plates solidified with these alternative gelling agents. Indeed, a rhlA-null mutant unable to produce its wetting agents still spreads effectively, albeit in a circular shape on both the gellan gum- and carrageenan-based media. Our data indicate that rhamnolipids do not have such a crucial role in achieving surface colonization of non-agar plates, suggesting a strong dependence on the physical properties of the tested surface. The use of alternative gelling agent provides new means to reveal unknown features of bacterial surface behaviour.

Certain Soil Surfactants Could Become a Source of Soil Water Repellency after Repeated Application

Repeated application of soil surfactants, or wetting agents, is a common practice for alleviating soil water repellency associated with soil organic coatings. However, wetting agents are organic compounds that may also coat soil particle surfaces and reduce wettability. For this experiment, hydrophobic sands from the field and fresh, wettable sands were collected and treated with either a polyoxyalkylene polymer (PoAP) or alkyl block polymer (ABP) wetting agent, or water only treatments served as a control. Following repeated treatment application and sequential washings, dissolved and particulate organic carbon (OC) were detected in the leachates of both sand systems. The total amount of OC recovered in leachates was 88% or less than the OC introduced by the wetting agents, indicating sorption of wetting agent monomers to soil particle surfaces regardless of soil hydrophobicity status. While ABP treatment did not alter solid phase organic carbon (SOC) in the sands studied, PoAP application increased SOC by 16% and 45% which was visible in scanning electronic microscopy images, for hydrophobic and wettable sands, respectively. PoAP application also increased the hydrophobicity of both sands that were studied. In contrast, ABP treatment increased the wettability of hydrophobic sand. Our results provide strong evidence that certain wetting agents may increase soil hydrophobicity and exacerbate wettability challenges if used repeatedly over time.

Study, Nonylphenol Analysis of Textile Liquid Discharges of the City of Marrakech

Nonyphenols, especially the ethoxylated derivatives of nonylphenol (NPE) known as ethoxylated alkylphenols (APEs), are synthesized for their surfactant properties, which allow a better dispersion of liquids and the miscibility of certain substances such as oil and water. More than 40 years have been used as detergents, emulsifiers, wetting agents and dispersing agents and even cosmetic products such as shampoos. These organic molecules are very persistent and well known by their predatory toxicities on the skin, the eye, the respiratory tract, the kidneys and the liver, they are endocrine disruptors. The textile industry via some ennobling chemicals, tissue contamination and liquid discharges by these molecules remains a concern for the industry and the quality of these discharges. Our goal is to verify the contamination of liquid discharges from a textile industry using certain chemicals in the dyeing process.

Potential effect of wetting agents added to agricultural sprays on the stability of soil aggregates

The presented research deals with the issue of the potential effect of adjuvants/wetting agents (WA) added to the spray mixture for stability of soil aggregates (SAS) in agricultural soil. Nine localities were chosen in the Czech Republic. Each locality was mapped using soil pits (depth min. 1.4 m). A total of 54 mixed samples were collected from the topsoil horizon in the selected localities. The samples were exposed to the action of four different types of wetting agents (organosilicone wetting agent; methyl ester of rapeseed oil; mixture of methyl ester palmitic and oleic acids; Isodecyl alcohol ethoxylate). SAS was determined before and after the addition of WA. Average values of SAS across the sampling point exhibited a demonstrable trend: the SAS value of control sample (without WA application) was at all times higher than in samples with the addition of WA (organosilicone wetting agent; mixture of methyl ester palmitic and oleic acids; Isodecyl alcohol ethoxylate), on average by more than 15 %. If the measured SAS values are compared in terms of overall means, it is obvious that the control variant always exhibited the highest SAS value (44.04 %) and the variants with the application of WA showed always SAS values lower by min. 16 %. All soil samples were also analysed for basic soil parameters (glomalin, Cox, pH, Na, P, Ca, K, Mg) in order to determine their potential influence on SAS and a possible elimination of the negative impact of WA. In this respect, only a significant influence of Cox content on SAS was recorded, which positively correlated with SAS.

Copolymerization of Acrylic Monomers and Silane Group Containing Titanium Carbide Nanoparticles for Application to Ophthalmic Lens Materials

This research was conducted to synthesis and application for high oxygen permeable ophthalmic lens materials. 2-(Trimethylsiloxy)ethyl methacrylate (2T), 3-[Tris(trimethylsiloxy)silyl]propyl methacrylate (3T), [(1,1-Dimethyl-2-propynyl)oxy]trimethylsilane (TMS), Poly(ethylene glycol) methyl ether methacrylate (PEGMA), N-vinyl-2-pyrrolidone (NVP) and titanium carbide nanoparticles were used as additives for the basic combination of synthesized silicone monomer (SiD) and N,N-Dimethylacetamide (DMA). And also, the materials were copolymerized with ethylene glycol dimethacrylate (EGDMA) as the cross-linking agent, azobisisobutyronitrile (AIBN) as the initiator. The copolymerization with a small amount of silane of about 1% increased the oxygen permeability to 30.3˜33.52(cm2/sec)·(mlO2/ml·mm Hg)·10−11, and in particular, the addition of titanium carbide nanoparticles was found to increase to 46.38 (cm2/sec)·(ml O2/ml·mm Hg)·10−11. Surface modification was possible with various wetting agents. Especially, simultaneous use with titanium carbide nanoparticles increased the wettability while maintaining water content. These materials are considered to make synergy effect each other, so it can be used in functional hydrogel ophthalmic lenses.

Effect of Modeling Resins on Microhardness of Resin Composites

Objectives This study was aimed to determine the effects of modeling resins on the surface microhardness of composites. Materials and Methods Six resin-based composites (Charisma Smart, Estellite Asteria, CeramX-One SphereTEC, Admira Fusion, Filtek Ultimate, and Clearfil Majesty Es-2) and three wetting agents (Modeling Liquid, Composite Primer, and Modeling Resin) were investigated. In all, 240 specimens were prepared, and wetting agents were applied prior to light curing in the experimental groups. After 24 hours, specimens were polished and Vickers microhardness (VHN) values were measured. Statistical Analysis Shapiro–Wilk and two-way analysis of variance (ANOVA) were used for analyses (p < 0.05). Results Both modeling resin and composites were determined to be effective factors (p < 0.001). The control group showed the highest VHN (70.37 ± 7.94), followed by Modeling Liquid (64.68 ± 12.07), Composite Primer (59.84 ± 6.33), and Modeling Resin (58 ± 3.52b; p < 0.001). Filtek Ultimate showed the highest VHN (76.62 ± 9.78c), whereas Charisma Smart (58.87 ± 7.95), and Clearfil Majesty (67.27 ± 2.58) showed the lowest (p < 0.001). Clearfil Majesty–Modeling Liquid (46.62 ± 5.33) and Charisma Smart–Composite Primer (50.81 ± 0.39) combinations showed the lowest VHN, whereas Filtek Ultimate–control (87.15 ± 2.12) and Filtek Ultimate–Modeling Liquid (84.24 ± 3.11) showed the highest (p < 0.001). Conclusion All tested modeling resins decreased VHN value, and the amount of reduction varied among composites and wetting agents. It might be safer not to use wetting agents unless they are necessary.