High Thermal-oxidative Stability Research Articles

Development of poly(butylene adipate‐co‐terephthalate) composites with high thermal oxidation stability using Chrysanthemum morifolium extract as a natural additive

AbstractPoly(butylene adipate‐co‐terephthalate) (PBAT) is one of the solutions to the energy crisis and white pollution. However, the poor thermo‐oxidative stability limits its wide applications. In this work, Chrysanthemum morifolium extract (CME) as a natural additive was used to modify the PBAT. The oxidation onset temperature (OOT) results showed that the CME could provide PBAT with high thermal oxidation stability. By the presence of 2.5 wt% CME, the OOT value of PBAT‐CME2.5 increased by 52°C compared with the neat PBAT. The outstanding antioxidant capacity is attributed to the excellent free radical quenching capacity of CME, whose main components consist of six kinds of phenolic compounds. Moreover, the PBAT‐CME1.5 composite could achieve the balance between the mechanical property and thermo‐oxidative stability, the OOT result of PBAT‐CME1.5 increased by 42°C, the tensile strength reached 103.1%, and the elongation at break could retain 91.4% of that of neat PBAT. Besides, the processing property, degradation performance, and surface hydrophobic nature of modified PBAT samples were all improved. This work proposes a facile method to obtain completely natural biodegradable composites to expand the practical applications of PBAT.Highlights The main components in CME are phenolic compounds. CME showed high free radical scavenging efficiency. CME improved the thermal oxidation stability of the PBAT matrix. The addition of CME could still maintain good mechanical properties of PBAT. The introduction of CME promoted the degradation of PBAT films.

Controlling the reactivity of hydrophilic bark extractives as biopolyols in urethane-formation reactions using various catalysts

The composition, functionality, and reactivity of black alder (Alnus glutinosa) bark extractives as a biopolyol with polymeric diphenyl methane diisocyanate (PMDI) have been studied using a variety of methods, including HPLC, GPC, GC, wet chemistry, and isothermal calorimetry. The Black alder (BA) bark extractives were identified as a prospective polyol consisting mainly of the oregonin-xyloside form of diarylheptanoid, which contains OH groups that are almost equally represented by phenolic and aliphatic origins. To identify catalysts that effectively increase the reactivity of low-active phenolic OH groups in urethane formation reactions, the kinetics of extractives and model compounds' interaction with PMDI catalyzed with tin organic, dibutyl tin dilaurate (DBTDL) and tertiary amine, 1,4-diazabicyclo[2.2.2]octane (DABCO) catalyst in dimethylsulfoxide (DMSO) solution were studied. The results showed that DABCO resulted in a fourfold higher reactivity of phenolic groups with PMDI compared to DBTDL catalyzed reactions. Furthermore, the reactivity of phenolic groups with PMDI catalyzed by DABCO was almost twofold greater than that of aliphatic OH catalyzed by DBTDL. The second-order constants of 31.9 × 10−4 mol·L−1·s−1 and 53.7 × 10−4 mol·L−1·s−1 were determined for the interaction of extractives with PMDI in the presence of DBTDL and DABCO, respectively. The disappearance of the radical scavenging effect of phenolic compounds in extractives derived PU elastomers obtained with DABCO catalyst indicates complete reactions of phenolic groups with isocyanate, while these groups remain partly free in the case of DBTDL catalysis. It is assumed that a combination of DBTDL and DABCO catalysts will be necessary to achieve high crosslinking while leaving a small portion of free phenolic groups in the bio-based PU network, thus obtaining material with high mechanical properties and thermal oxidative stability.

Acid-catalyzed rearrangement of biomass polycyclic sesquiterpene derivatives to high-performance alkyl-adamantanes

Biomass-based aviation fuel is attractive for sustainable development. Herein, we report a facile route to synthesize alkyl-adamantanes (AAMs) via acid-catalyzed rearrangement of biomass polycyclic sesquiterpene derivatives (bio-PCS derivatives). The reaction conditions including catalysts, solvents, reaction temperature and reaction time were optimized. Notably, a total AAMs yield of 65.1% was achieved under the optimal conditions. The kinetics of rearrangement reaction was investigated, and the reaction rate constant (k) and apparent activation energy (Ea) were calculated based on the experimental kinetic data. The rearrangement products possess high density of 0.90 g/cm3, high net heat of combustion of 42.6 MJ/kg, low viscosity (22.5 mm2/s at −20℃) and high thermal oxidative stability. The blending of rearrangement products with JP-10 can significantly shorten the ignition delay time (IDT) of JP-10. This work provides a method to synthesize high-performance biomass-based AAMs.

Fabrication of Nanoparticle‐Doped Polyvinyl Alcohol‐Cellulose Acetate Membrane and Characterization of the Surface Enhancement

AbstractIn the present study, nanocomposite polymeric membranes are fabricated using polyvinyl alcohol (PVA), cellulose acetate (CA) as polymers, and dimethyl sulfoxide (DMSO) as the solvent. To enhance the performance of the membrane, nanoparticles like TiO2, CaO, CdO, and ZrO are added to the polymeric solution and the doped polymeric solution is cast on a glass plate. Nine combinations of membranes are fabricated with two different concentrations (0.1% and 0.2%) of nanoparticles. The basic properties of the membranes such as density, porosity, viscosity, permeability, pure water flux, and water content are studied for the samples. Membrane pore structure and surface properties are identified and it is found that doping nanoparticles on the surface of membranes improve mechanical strength, stability, pore size, etc., allowing the membranes to perform better in extreme industrial‐level effluent treatment applications. High‐resolution scanning electron microscopy (SEM) shows the homogeneous dispersion of ZrO, TiO2, CaO, and CdO nanoparticles on the surface of the PVA‐CA membrane. The doping of nanoparticles on the PVA‐CA membrane results in improved mechanical strength and good chemical oxidation stability. In comparison, the PCD‐TiO2 sample shows high thermal stability and oxidation stability at high temperatures until 200°C, which has a high potential for treating industrial effluents.

Novel Method for Deposition of Gas-Tight SiC Coatings

A new high-temperature method for the deposition of gas-tight silicon carbide protective coatings with low gas permeability has been developed. The free carbon atoms form during the high-temperature pyrolysis of hydrocarbon molecules. In turn, carbon reacts with molten silicon contained in the subsurface substrate layers and/or with silicon vapor. The source of silicon vapor serves the molten silicon in the heated zone of a reactor furnace. Such coatings effectively protect SiC-C-Si and SiC-C-MoSi2 ceramics, carbon–carbon composite materials, structural graphite, and refractory metals and alloys from oxidation. The conducted tests show the high thermal oxidation and thermal shock stability of deposited protective coatings, as well as their good adhesion to the substrates.

A new-generation poly (ether imide sulfone) based solvent resistant ultrafiltration membrane for a sustainable production of silica nanopowder

The work presented here demonstrated the feasibility of using a membrane to improve the sustainability of silica nanopowder production. Due to superior chemical resistance, high thermal-oxidative stability, and good processability, poly (ether imide sulfone) has been used for membrane production and modified with amine-functionalized TiO2 nanoparticles. The membrane demonstrated good long-term leaching stability in 40% ethanol and silica synthesis solution and maintained its permeability and rejection characteristics under static and dynamic conditions. Additionally, the high antifouling property of the membrane allowed recovering 99.5% of the nanoparticles. Backwashing with water resulted in a high flux recovery ratio (>93%), and gravity-settling without energy can easily separate silica nanoparticles and water in the backwashing solution. Compared to classical freeze-drying and oven-drying methods, integrating membrane into silica nanopowder production can reduce energy consumption by a factor of 81 and 53. At the same time, the utility cost can be saved by 80% and 69%. Additionally, the solvent and catalyst recovered in the permeate stream can be reused in the synthesis, reducing disposal and purchasing costs. In conclusion, membrane-assisted nanopowder production can minimize the adverse effects caused by commonly used conventional drying methods and make the process more sustainable and environmentally friendly.

The dynamics and mechanism of JP-10 thermal oxidative deposition

High-energy–density (HED) fuels (like JP-10) have drawn more and more attention for volume-limited aerospace vehicles to extend the flight range and/or increase the payload. However, their thermal oxidation and deposition performance are still ambiguous. In this work, the dynamics and mechanism of JP-10 thermal oxidative deposition were investigated by the jet fuel thermal oxidation stability tester (JFTOT), ellipsometric tube rater (ETR) and comprehensive two-dimensional gas chromatography coupled with mass spectrometry and flame ionization detector (GC × GC–MS/FID). The results reveal that both the peak deposit thickness and total deposits volume of JP-10 increase with increasing temperature with the apparent deposition activation energy of approximately 71.2 kJ/mol. The deposits on the tube surface have globular structure, and they undergo particle formation, growth, adherence, agglomeration and size reduction during thermal stress. The fine characterizations of liquid products after JFTOT test confirm that the thermal oxidative deposition of JP-10 occurs via a series of radical reactions, such as oxidative decomposition and radical addition, which will be significantly accelerated at higher temperature. Importantly, the stability of alkoxy radical seems to be a significant factor affecting the thermal oxidation stability of HED fuels. This work may shed light on the possible deposition mechanism of HED fuels and will guide the rational design of HED fuels with high thermal oxidation stability.

Synthetic oils based on pentaerythritol esters. Vapor pressure and enthalpy of vaporization

Pentaerythritol esters (2,2-bis(hydroxymethyl)propane-1,3-diol) esters and other esters are widely used as components of machine oils, motor oils, hydraulic fluids and plasticizers. The advantages of such esters are high thermal oxidative and hydrolytic stability, and good tribological properties. In this work, the equilibrium vapor pressures and enthalpies of vaporization (298.15 K) of nine esters of pentaerythritol combined with C2–C7 acids of various structures were determined by the vapor transpiration method in the temperature range of 358–433 K. The vaporization enthalpies of the pentaerythritol esters with homologous acids are found to correlate with their retention indicies and the number of carbon atoms in the linear acid residue. Enthalpies of vaporization of the compounds studied have also been calculated by the QSPR-method. These results have been verified by experimental values.

Study of Causes of Plastic Pipe Failures

It has been observed that critical failures and loss of function occur in a shorter period than specified service life during operation of polypropylene pipes in hot water systems. The paper analyzes the failure causes of polypropylene pipes in closed loop hot water systems, and provides recommendations for increasing their service life. It has been established that the primary factors responsible for ageing and failure of polypropylene pipes during operation are medium temperature, stress due to internal pressure, water composition. It has been observed that a combined influence of the above mentioned factors provides a synergistic effect. We developed the recommendations for increasing a pipe service life, including close monitoring and recording of energy carrier temperature and pressure; changes in specifications for propylene pipes, including the recommendation for using random propylene pipe grades with high thermal oxidation stability in hot water systems.

Ultralow-density carbon foam composites with bean-like Co-embedded carbon nanotube whiskers towards high-performance microwave absorption

We describe the design and fabrication of an ultralight carbon foam composite with special bean-like Co-embedded carbon nanotube whiskers used for high-performance microwave absorption materials. A facile approach was developed to create this carbon foam with the self-growth of carbon nanotubes on low-cost cobalt-decorated commercial melamine sponges (MF) via a simple thermal annealing process. It was found that a large number of bean-like carbon nanotubes whiskers (1D) embedded with Co nanoparticles (0D) grew on the surface of carbon skeleton (3D) under the action of surface autocatalysis. This unique hierarchical micro/nanostructure not only reduced the density of the materials but also effectively improved their thermal oxidation stability and microwave absorption ability. The resultant foam showed an excellent microwave absorption performance with the combined advantages of ultralow density (9.4 mg/cm3), strong absorption (minimum reflection loss value of −46.2 dB), wide absorption width (4.8 GHz), and high thermal oxidation stability (>350 °C). The RL values of the foam could be all below −10 dB at the frequency from 4 to 18 GHz covering 87% of the whole test frequency range. These remarkable results also provide a potentially scalable, simple, and cost-effective strategy for designing metal-embedded carbon composite nanostructures for catalysis, electrochemistry, and other applications.

Green preparation of branched biolubricant by chemically modifying waste cooking oil with lipase and ionic liquid

To reduce the environment pollution from biolubricant synthesis, in this study, we developed a green and efficient strategy for the preparation of octylated branched biolubricant from waste cooking oil (WCO): (1) WCO was first hydrolyzed by a lipase (Candida sp. 99–125) to produce unsaturated fatty acids (UFAs), the latter was subsequently concentrated by urea complexation; (2) Next, we synthesized new esters using the UFAs as substrate via esterification with 2-ethylhexanol employing lipase (Novozym 435) and the new esters products were further epoxidated; (3) After that, the epoxy group was attacked by a low-cost nucleophilic reagent, octanoic acid, to prepare octylated branched biolubricant using an recyclable ionic liquid, [HMIm][PF6], as catalyst. After three recycling times, [HMIm][PF6] remained catalytic activity with a conversion yield of 81.22% and selectivity of 82.10%. The obtained product showed excellent lubricant properties, such as low pour point of −61 °C, high viscosity index of 149 and high thermal-oxidation stability (onset temperature of 326.35 °C and oxidative onset temperature of 312.06 °C). The high frequency reciprocating rig (HFRR) measurement demonstrated that lubrication performance (friction coefficient of 0.09 and wear spot diameter of 203 μm) was much better than that of mineral based lubricant with the same viscosity grade. Therefore, this study provided a critical synthetic strategy for preparing high-performance biolubricants from WCO.

Design of S-Substituted Fluorinated Aryl Sulfonamide-Tagged (S-FAST) Anions To Enable New Solvate Ionic Liquids for Battery Applications

Electrolytes with improved thermal and oxidative stability must be developed to achieve greater power and energy densities without compromising safety in modern energy storage devices. Because of their much-reduced solvent vapor pressure and expanded electrochemical windows, solvate ionic liquids (SILs) of lithium salts have recently attracted significant attention in this regard. The current palette of SILs is, however, limited to only a few suitable anions with limited chemical functionality. Guided by fundamental physical organic chemistry principles, we designed a new family of S-substituted fluorinated aryl sulfonamide-tagged anions that feature variable numbers of electronically neutral or withdrawing sulfide, sulfoxide, and sulfone substituents. Several salts of these electron deficient anions display very high electrochemical oxidative stability, good solubility, and a weakly coordinating nature that enables the synthesis of Li-based SILs with high thermal and electrochemical oxidative stability. This new family of functional, noncoordinating anions will potentially expand the scope of applications of SILs as safe electrolytes in battery devices.

X-ray diffraction, vibrational and thermal study of dibenzazepinodione, a pharmacopeial impurity of oxcarbazepine

The antiepileptic drug oxcarbazepine (OXC) was crystallized from various organic solvents, and mixtures of OXC crystals and red-orange particles were obtained. In view of the pharmaceutical relevance of OXC, this study focuses on the isolation and characterization of these red-orange crystals by structural [single crystal (SCXRD), powder X-ray diffraction (PXRD) and Hirshfeld surface analysis], vibrational [Fourier transform infrared (FT-IR), Fourier transform Raman (FT-Raman) and Density functional theory (DFT) calculations], and thermal methods of analysis [simultaneous thermogravimetry-differential thermal analysis (TG-DTA) and hot stage microscopy (HSM)]. According to SCXRD, the red-orange crystals corresponded to a recently codified impurity of OXC, referred as dibenzazepinodione (DBZ) or impurity D in the United States and European Pharmacopoeias respectively, which crystallized in the orthorhombic Pccn space group with a half-molecule in the asymmetric unit. Hirshfeld surface analysis revealed that weak intermolecular contacts played an important role in the stabilization of DBZ packing. DBZ was also characterized through its mid-infrared and Raman spectra and its vibrational bands were assigned based on DFT calculations with the hybrid B3LYP functional, coupled with the 6-311++g (d,p) basis set. The TG-DTA and HSM results shed light on the behaviour upon heating of DBZ, revealing that this impurity is an unsolvated solid with high thermal-oxidative stability, which sublimed, melted locally and decomposed above 320 °C. The obtained results demonstrated that slow crystallization of OXC from solvents such as ethanol and dimethylsulfoxide, at 20-25 °C, in the presence or absence of ambient light afforded DBZ. The X-ray pattern based on the SCXRD data for DBZ is presented as reliable reference for its identification.

Oxidation stability of yeast biodiesel using Rancimat analysis: validation using infrared spectroscopy and gas chromatography-mass spectrometry.

Biodiesel and single cell oils obtained from oleaginous yeasts grown in industrial waste are attractive alternatives to the conventional fuels. However, there are only few articles dealing with the stability of the microbial biofuels. Hence, this study aimed at characterizing the storage time of biodiesels using Rancimat methods. The microbial oil and the biodiesel obtained from microbial oil have been characterized with storage stability due to various oxidizing and thermal damage. Here, the microbial fuels were subject to Rancimat analysis and found to have high thermal-oxidative stability of 18 and 8.78h for biodiesel and oil, respectively. The storage stability resulting from storage conditions was extrapolated for biodiesel and oil and has been found to be 1.62 and 0.54years, respectively. The infrared spectroscopic analysis reveals the degree of oxidation found after the induction time was reached and shows the characteristic peaks for degradation products. Gas chromatography revealed the compounds that were responsible for the stability as well as the amount of degradation products left.

Polyethylene containing antioxidant moieties exhibiting high thermal-oxidative stability for high temperature applications

A new class of polyethylene-bonded antioxidants (PE-HP), containing several hindered phenol (HP) groups located along the polymer chain, has been prepared and investigated in this paper. The homogeneously distributed HP groups not only provide polymer stability but also form a completely polymer network under elevated temperatures. In a TGA comparative test, the PE-HP copolymer with 1.1 mol% HP concentration demonstrates no weight loss after heating at 190 °C in air for 1000 min, while the commercial HDPE exhibits weight loss within 100 min. A standard ASTM oxygen induction time (OIT) test also shows heat flow to commercial HDPE after 15 min at 190 °C in air, while the PE-HP copolymer with 1.1 mol% HP groups shows a complete flat OIT line up to 230 min, without any detectable onset heat flow into the sample. This new PE-HP copolymer shall expand HDPE application to high temperatures (>150 °C).

Pistachio (Pistachia vera) wastes valorization: Enhancement of biodiesel oxidation stability using hull extracts of different varieties

Abstract Biodiesel degradation through autoxidation radical chain reactions adversely affects long-term storage stability, high thermal oxidation stability, and consequently biodiesel consumers’ acceptance. Propyl gallate, the most promising synthetic antioxidant, is widely used to address this challenge. However, the application of this synthetic antioxidant is associated with health concerns such as risk of brain tumors as proposed by the National Toxicology Program (U.S. Department of Health and Human Services). Herein, the application of a naturally-originated alternative to propyl gallate, i.e., pistachio hull extract in canola biodiesel was investigated from technical and environmental viewpoints. According to the results achieved, a concentration of 2500 ppm of the bio-antioxidant and 250 ppm of the synthetic antioxidant was needed to improve the induction period of the investigated biodiesel from 1.53 h to above 3 h as required by ASTM D6751-12 specification for biodiesel oxidation stability. In spite of the fact that the higher concentration of the bio-antioxidant was required, its application would be justified by the probable health hazards of its synthetic counterparts. On the other hand, 23% of the global biodiesel production takes place in top pistachio producing countries where a huge amount of pistachio fresh hulls are generated. Therefore, valorization of this considerable agro-waste stream into a natural antioxidant, i.e., pistachio hull extract, seems to be a promising strategy to enhance the favorable environmental and health aspects of biodiesel. In addition, life cycle assessment revealed that the production and application of the bio-antioxidant were favorable from the climate change and human health perspectives compared with propyl gallate.

INVESTIGATION OF INFLUENCE OF ESTER STRUCTURE ON THERMAL-OXIDATIVE OILS STABILITY

This work aims are analysis the influence of the structure of esters on their thermo-oxidative stability. Then we select the composition of additives to improve the oxidation properties of aviation turbine engines. As the main method we used the following study: Standard Test Method for Corrosiveness and Oxidation and Stability of hydraulic oils, aircraft turbine engine lubricants and other highly refined oils ASTM 4636-99. It has been found that the esters of dicarboxylic acids and aliphatic alcohols have a low thermal oxidative stability, which may result in frequent change in the oil lubrication system and washing with gasoline or jet fuel. Thus, compositions based on esters of dibasic acids and aliphatic alcohol are good plasticizers having abrasion resistance and frost resistance. Thought they have low pour points and high viscosity index. As a basis for aviation oil hindered esters are recommended, which have high thermal oxidative stability. In the industry esters obtained by etherification of the mixture of acids and a polyhydric alcohol are used. Esters are optimal on its viscosity-temperature properties which were obtained in the reaction of etherification of pentaerythrit and trimetilolpran alcohols, and mixtures of hexane, heptane, nonanoic, octanoic acids. Physico-chemical parameters of esters are improved with increasing in number of functional groups in the molecule. The reason for this is that the esters were obtained by the reaction of etherification of n-C9 acids with pentaerythritol alcohols which forms a sterically hindered ester. This structure has no hydrogen atom in the molecule in β-position, which prevents the formation of cyclic hydrocarbons. However, to get oils with high performance require it is necessary to add additives. Therefore, domestic and foreign literatures and requirements for oxidation stability were analyzed. Based on these data the main requirements were formulated for oil composition of aircraft gas turbine engines. As the results of the oxidative stability testing it were found that to obtain oil which satisfies to all modern requirements for thermal oxidative stability, it requires the use of complex of antioxidants of phenolic and amine types. Forcitation:Tonkonogov B.P., Bagdasarov L.N., Popova K.A., Agabekov S.S. Investigation of influence of ester structure on thermal-oxidative oils stability. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2018. V. 61. N 2. P. 73-79

Structural analysis of a-C:H and a-C:H:Si films under high-pressure and high-temperature by synchrotron X-ray diffraction

Amorphous carbon films have several outstanding tribology characteristics, including high hardness, surface smoothness, and low friction. Under tribological conditions, their surface is generally exposed to high-temperature and pressure. Although the structure of amorphous carbon films is likely changed by high temperature and pressure, there have been no reports on such structural changes of the films. To obtain information about their structural changes, synchrotron X-ray diffraction was used to analyze two kinds of amorphous carbon films, a-C:H and a-C:H:Si, under high-temperature and high-hydrostatic pressure conditions. Synchrotron X-ray diffraction was applied to films pressurized by a multi-anvil press installed in the PF-AR NE5C beamline at KEK at room temperature and at a high-temperature around 200°C. The pair distribution functions derived by Fourier transformation of the obtained scattering intensity profiles showed that the sp2/sp3 ratios for both films decreased as the pressure increased and that the sp2/sp3 ratio for the a-C:H film increased as the temperature increased. This indicates that high-pressure creates sp3 stabilization in a-C:H and a-C:H:Si films while high-temperature creates sp2 transition in a-C:H film. The sp2/sp3 ratio for the a-C:H:Si film did not change much even at high-temperature due to the high thermal-oxidative stability of a-C:H:Si.

Effect of Modified Silica Particles with Phenyltriethoxysilane on Mechanical and Thermal Properties of Natural Rubber Composites

SummaryThe modification of silica surface by phenyltriethoxysilane (PhTES) as a modifying agent was carried out by sol‐gel reaction of tetraethoxysilane (TEOS) as a precursor of silica. The condition to modify silica particles was the use of the mole ratio of TEOS to PhTES of 1:0.4 and ammonia as a catalyst at ambient temperature for 24 h. The characterization of modified silica surface was investigated by a fourier transform infrared spectroscopy and contact angle measurement. The modified silica particles were in a spherical shape, which was confirmed by a scanning electron microscopy. The mechanical properties and thermal stability of modified silica particles filled NR vulcanizates were greatly improved compared to those of unfilled NR vulcanizates due to the reinforcing effect and the high thermal oxidative stability of modified silica particles, respectively.

Study on Preparation and Property of High Thermal Oxidation Stability PPS/SiO<sub>2</sub> Fiber

PPS/SiO2 composite was studied to enhance the thermal oxidation stability of PPS. In order to improve the dispersity of SiO2 in PPS matrix, the SiO2 was modified by silane coupling agent, KH-570. The fractured surface morphologies, thermal properties and rheological property of PPS/SiO2 composite were researched. The high thermal oxidation stability PPS/SiO2 fibers were prepared by melt spinning. The thermal ageing treatment was carried out, and the strength and retention strength, before and after ageing treatment, of two kinds of fibers (PPS fibers and PPS/SiO2 fibers) were compared. The results of SEM showed the good dispersity of the modified SiO2 in PPS matrix. After adding modified SiO2, the initial decomposition temperature increased. At the same time, the fiber strength and retention strength were improved, which can be found by comparing. Compared with pure PPS, after adding 1.0 wt%, which was proved to be the optimum dosage by the research, modified SiO2 into PPS, the initial decomposition temperature was increased by 15.3°C, the retention strength was increased from 60.3% to 85.1% after ageing treat.