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This study explores the impact of butadiene rubber (BR) crystallization on the low-temperature properties of butadiene/silicone (VMQ) rubber blends (BR/VMQ) designed for Martian applications. Two types of BR, semi-crystalline high-cis Buna CB24 and amorphous Buna CB550, were blended with VMQ, and their mechanical and thermal properties were evaluated. Kinetics of vulcanization, static mechanical properties, dynamical mechanical analysis, thermal shrinkage, and differential scanning calorimetry were utilized. The research demonstrates that the semi-crystalline BR improves mechanical properties but induces greater shrinkage at low temperatures. Conversely, using amorphous BR provided more consistent mechanical properties across the Martian temperature range and reduced material shrink by 6.71% for samples with carbon black, by 8.36% for samples with silica, and by 11.63% for unfilled samples. Future research will be required to evaluate the impact of volume change on the sealing properties of the BR/VMQ blends. [ABSTRACT FROM AUTHOR]

The use of depressant additives is the most effective and cost-effective way to improve the low-temperature properties of diesel fuels, like the cloud point, cold filter plugging point and pour point. However, the effectiveness of depressant additives depends on the composition of the diesel fuel and the content of certain groups of hydrocarbons in it. In this work, the effect of adding individual hydrocarbons of various groups and structures on the effectiveness of depressant additives is studied. This study is carried out on model aromatic (toluene, tetralin) and n-paraffin hydrocarbons (cetane, heptadecane, heneicosane, docosane) in various concentrations. It is shown that the most negative effect on the depressant additives' effectiveness is due to the content of the most polar aromatic hydrocarbons and light n-paraffins in the composition of diesel fuel, and the most positive effect is exerted by the content of heavy n-paraffins in small quantities. It is proposed to involve small concentrations (1–3% vol.) of heavy n-paraffin hydrocarbons (heneicosane, docosane) to increase the effectiveness of the depressant additive. It has been established that for the more effective action of the depressant, it is necessary to take into account the content and structure of individual hydrocarbons in the diesel fuel's composition. [ABSTRACT FROM AUTHOR]

Biomass heavy oil, a renewable green energy source, has been extensively explored for its preparation process and material properties. This study examined the applicability of biomass heavy oil integrated into matrix asphalt. Bio-asphalt samples were prepared using polymer-modified asphalt I-C as the matrix asphalt, blended with straw liquid oil, straw solid oil, and castor liquid oil. The low-temperature performances of these samples were assessed. First, the effects of bio-oil on the fundamental performance of asphalt were analyzed through three-component tests, encompassing a short-term aging test and a temperature scanning test based on dynamic shear rheometry. Subsequently, the effects of the chemical composition of bio-asphalt on its fundamental performance were examined through four-component tests, including SARA, gel-permeation chromatography (GPC), and gray entropy correlation. The glass transition temperature (Tg) was considered a parameter for evaluating the low-temperature properties of the bio-asphalt binders. The bending-beam rheometry (BBR) low-temperature creep test and the binder fracture energy (BFE) full-section fracture energy test revealed that adding bio-oil reduces Tg of the matrix asphalt. The integrated creep flexural parameter Jc and the BFE fracture energy density values indicated that the low-temperature fracture-resistant properties of bio-asphalt surpass those of the matrix asphalt. Furthermore, the low-temperature cracking resistance of the bio-asphalt samples was determined through the BFE test. Gray entropy correlation analysis of the low-temperature performance indicators of bio-asphalt revealed that the BBR test is suitable for evaluating low-temperature performance only up to − 12 °C. In summary, the bio-asphalt mixtures demonstrate exceptional fatigue resistance under low-temperature service conditions. Therefore, bio-oil emerges as an effective candidate for enhancing the low-temperature performance characteristics of matrix asphalt.

This study explores the impact of butadiene rubber (BR) crystallization on the low-temperature properties of butadiene/silicone (VMQ) rubber blends (BR/VMQ) designed for Martian applications. Two types of BR, semi-crystalline high-cis Buna CB24 and amorphous Buna CB550, were blended with VMQ, and their mechanical and thermal properties were evaluated. Kinetics of vulcanization, static mechanical properties, dynamical mechanical analysis, thermal shrinkage, and differential scanning calorimetry were utilized. The research demonstrates that the semi-crystalline BR improves mechanical properties but induces greater shrinkage at low temperatures. Conversely, using amorphous BR provided more consistent mechanical properties across the Martian temperature range and reduced material shrink by 6.71% for samples with carbon black, by 8.36% for samples with silica, and by 11.63% for unfilled samples. Future research will be required to evaluate the impact of volume change on the sealing properties of the BR/VMQ blends.

Poultry waste poses serious environmental and health problems because it emanates offensive odor and promotes fly and rodent breeding. Appropriate utilization of such waste and its by-products can simultaneously prevent side effects and provide an economic advantage. In this study, poultry waste oil and its methyl ester derivatives were converted to biolubricants in a two-step sequential chemical modification process: epoxidation using in situ formed peroxyformic acid and epoxide ring-opening with isoamyl alcohol in the presence of p-toluenesulfonic acid. The biolubricants obtained from the epoxidized chicken waste oil and epoxidized methyl esters by the ring-opening reaction were characterized. The viscosity index and pour point of the biolubricant synthesized from epoxidized chicken waste oil were 111.32 and − 2 °C respectively. It was observed that the pour point of the biolubricant produced for chicken oil is lower compared to the pour point of the biolubricant produced from FAME. However, the lubricants derived from epoxidized methyl esters exhibited slightly higher oxidative stability (18 h). Our results suggest that lubricant synthesized from poultry waste oil can be considered feasible alternative to petroleum-based lubricants as it matches the kinematic viscosity and low-temperature properties of the commercial lubricant ISO VG 32 grade oil. [ABSTRACT FROM AUTHOR]

The use of depressant additives is the most common method for producing diesel fuels with improved low-temperature properties. However, the depressants effectiveness largely depends on the composition of the diesel fuel, in particular on the content of n-paraffinic hydrocarbons, which to the greatest extent determine the low-temperature properties of the fuel. The work revealed the regularities of the n-paraffins addition influence on the depressant additives effectiveness. It was found that the addition of n-paraffins to blends of diesel fuels with depressants in low concentrations (0.05–0.50% wt.) enhances the depressants effectiveness in relation to the cold filter plugging point: maximum at 6–16 °C depending on the diesel fuel sample. It is shown that the effect is observed for DF of various compositions, various depressants, and also n-paraffins of various compositions. It was established that the positive effect of adding n-paraffins increases with the heavier added n-paraffins. Recommendations have been developed for obtaining diesel fuels with improved low-temperature properties and enhancing the depressant additives effectiveness: for a sample of straight-run diesel fuel F1, it is recommended to use a blend of fuel, depressant A1 and 0.50% wt. n-paraffins, separated from heavy gasoil; for a sample of straight-run diesel fuel F2, it is recommended to use a blend of fuel, depressant A2 and 0.50% wt. n-paraffins, separated from heavy gasoil or a blend of fuel, depressant A1 and 0.05% wt. n-paraffins, separated from highly paraffinic oil fraction. The revealed patterns and the developed recommendations will allow increasing the production of low-freezing DF brands, and also offer a resource-efficient option for using heavy gas oil fractions. The results obtained in the work contribute to expanding the understanding of the mechanism of interaction between diesel fuel hydrocarbons and the active ingredients of depressant additives. [ABSTRACT FROM AUTHOR]

The pavement recycling method is one of the practical ways to integrate sustainable development into transportation infrastructure, and it has been adopted worldwide. The use of reclaimed asphalt pavement (RAP) in new asphalt highways is limited due to the ageing effects caused by UV damage and weathering on the asphalt binder. To address this issue, waste vegetable oil (WVO) and waste engine oil (WEO) have been proposed as potential rejuvenating agents to enhance the recyclability of pavements containing RAP. This study evaluated the effectiveness of WEO and WVO as chemical rejuvenating agents through various tests on both aged and virgin asphalt binders. The tests included measurements of ductility, fire, and flash points, softening points, and penetration. The results indicate that the addition of WEO and WVO can improve the low-temperature properties of asphalt binders when mixed with RAP, resulting in reduced stiffness. The mixture containing WEO and WVO exhibited improved stability compared to the control, suggesting enhanced flow with increasing waste oil content in comparison to aged binder, albeit with slightly reduced flow compared to the virgin binder. This study demonstrates the potential of WEO and WVO as recycling agents to enhance the performance of bituminous mixes incorporating RAP. [ABSTRACT FROM AUTHOR]

This paper describes the synthesis of methacrylate-based terpolymer additives for diesel and biodiesel fuel that improve its properties at low temperatures. The synthesized additives contained different amounts of short-chain (methyl and benzyl) and long-chain (dodecyl and octadecyl) methacrylate comonomers. The crystallization behaviour of the additives and the formulations with diesel and biodiesel was observed by differential scanning calorimetry (DSC) and optical microscopy with polarization. DSC showed that the additives had a different effect on the crystallization temperature of the formulations. Microscopic images showed that the presence of additives influenced the size and number of wax crystals at low temperatures. Standard ASTM D5950 tests for pour point (PP) showed a large improvement in formulations with additives. In formulations with diesel, the addition of additives improved the PP value of diesel from − 18 °C to − 45 °C and in B10 diesel/biodiesel formulations from − 18 °C to − 54 °C. [ABSTRACT FROM AUTHOR]

The use of depressant additives is the most effective and cost-effective way to improve the low-temperature properties of diesel fuels, like the cloud point, cold filter plugging point and pour point. However, the effectiveness of depressant additives depends on the composition of the diesel fuel and the content of certain groups of hydrocarbons in it. In this work, the effect of adding individual hydrocarbons of various groups and structures on the effectiveness of depressant additives is studied. This study is carried out on model aromatic (toluene, tetralin) and n-paraffin hydrocarbons (cetane, heptadecane, heneicosane, docosane) in various concentrations. It is shown that the most negative effect on the depressant additives’ effectiveness is due to the content of the most polar aromatic hydrocarbons and light n-paraffins in the composition of diesel fuel, and the most positive effect is exerted by the content of heavy n-paraffins in small quantities. It is proposed to involve small concentrations (1–3% vol.) of heavy n-paraffin hydrocarbons (heneicosane, docosane) to increase the effectiveness of the depressant additive. It has been established that for the more effective action of the depressant, it is necessary to take into account the content and structure of individual hydrocarbons in the diesel fuel’s composition.

Depressor additives based on stearyl methacrylate homopolymer and its copolymers with various monomers (butyl methacrylate, methacrylic acid esters of С10–С14 fraction, maleic anhydride) were synthesized in the presence of reversible addition–fragmentation chain-transfer agents allowing control of the molecular-weight characteristics of the polymers. The low-temperature properties of the diesel fuel containing additives based on the above polymers were evaluated. The copolymers exhibit the better depressor effect compared to the stearyl methacrylate homopolymer. Modification of the stearyl methacrylate–maleic anhydride copolymer with 1-octanol was performed. The modified additive well competes in performance with the modern commercial depressor-dispersing additives and can decrease the congealing point of hydrotreated diesel fuels by 20°С. [ABSTRACT FROM AUTHOR]

Modern capabilities of additive technologies make it possible to maximize the metal utilization rate, reduce the carbon footprint, and ensure fast and high-quality manufacture of products of the required shapes and sizes with minimal deviations from the required geometric dimensions from metals, alloys, and polymeric materials. However, the almost complete absence of domestic producers of initial powders, as well as the lack of information about the features of structure formation in products made by 3D printing, especially taking into account operation in a wide temperature range, hinder the development of this industry. The article presents the results of investigating powders obtained from the atomized powder of steel 12Cr18Ni12Ti, and samples made by direct laser melting, across the temperature range from +600 to –196°C. [ABSTRACT FROM AUTHOR]

The addition of styrene butadiene styrene (SBS) to asphalt binders has led to enhanced performance in pavements across the entire range of working temperatures. SBS-modified binders have also proven to be more difficult to characterize in terms of their rheological properties. Low-temperature properties of asphalt binders are typically evaluated using the bending beam rheometer (BBR), which was developed to measure creep stiffness. Recent refinements to the BBR analysis have led to the development of ΔTc which is meant to provide more insight into the relaxation properties of the binder. The Asphalt Binder Cracking Device (ABCD) was developed to improve on this characterization by also taking into consideration the failure strength and coefficient of thermal contraction. Previous research has shown that the ABCD provides more valuable insight into the effect of SBS on the low-temperature properties of asphalt binders. This paper will evaluate the ability of these two low-temperature tests to characterize the performance of five different asphalt binders with increasing concentrations of SBS. It was found that the evaluation of the materials using ΔTc was inconsistent with binder type and generally indicated that SBS reduced cracking resistance, while the ABCD critical temperature and the proposed ΔTf parameter generally showed an improved correlation with SBS concentration. [ABSTRACT FROM AUTHOR]

As high brittleness limits the application of all epoxy resins (EP), here, it can be modified by high-performance thermoplastic poly(ether nitrile ketone) containing phthalazinone structures (PPENK). Therefore, the influence of different PPENK contents on the mechanical, thermal, and low-temperature properties of EP was comprehensively investigated in this paper. The binary blend of PPENK/EP exhibited excellent properties due to homogeneous mixing and good interaction. The presence of PPENK significantly improved the mechanical properties of EP, showing 131.0%, 14.2%, and 10.0% increases in impact, tensile, and flexural strength, respectively. Morphological studies revealed that the crack deflection and bridging in PPENK were the main toughening mechanism in the blend systems. In addition, the PPENK/EP blends showed excellent thermal and low-temperature properties (−183 °C). The glass transition temperatures of the PPENK/EP blends were enhanced by approximately 50 °C. The 15 phr of the PPENK/EP blends had a low-temperature flexural strength of up to 230 MPa, which was 46.5% higher than EP. Furthermore, all blends exhibited better thermal stability. [ABSTRACT FROM AUTHOR]

The use of depressant additives is the most common method for producing diesel fuels with improved low-temperature properties. However, the depressants effectiveness largely depends on the composition of the diesel fuel, in particular on the content of n-paraffinic hydrocarbons, which to the greatest extent determine the low-temperature properties of the fuel. The work revealed the regularities of the n-paraffins addition influence on the depressant additives effectiveness. It was found that the addition of n-paraffins to blends of diesel fuels with depressants in low concentrations (0.05–0.50% wt.) enhances the depressants effectiveness in relation to the cold filter plugging point: maximum at 6–16 °C depending on the diesel fuel sample. It is shown that the effect is observed for DF of various compositions, various depressants, and also n-paraffins of various compositions. It was established that the positive effect of adding n-paraffins increases with the heavier added n-paraffins. Recommendations have been developed for obtaining diesel fuels with improved low-temperature properties and enhancing the depressant additives effectiveness: for a sample of straight-run diesel fuel F1, it is recommended to use a blend of fuel, depressant A1 and 0.50% wt. n-paraffins, separated from heavy gasoil; for a sample of straight-run diesel fuel F2, it is recommended to use a blend of fuel, depressant A2 and 0.50% wt. n-paraffins, separated from heavy gasoil or a blend of fuel, depressant A1 and 0.05% wt. n-paraffins, separated from highly paraffinic oil fraction. The revealed patterns and the developed recommendations will allow increasing the production of low-freezing DF brands, and also offer a resource-efficient option for using heavy gas oil fractions. The results obtained in the work contribute to expanding the understanding of the mechanism of interaction between diesel fuel hydrocarbons and the active ingredients of depressant additives.

The process of hydrogen-free upgrading of diesel fraction on ZSM-5 type zeolite catalyst was implemented at the laboratory catalytic unit under the conditions of varying the process temperature. The composition and characteristics of the feedstock diesel fraction and the obtained upgrading products were investigated. The obtained diesel fraction upgrading products were tested for compliance with the standards. The directions of hydrocarbon transformations in the process of upgrading on a zeolite catalyst were considered. The influence of the upgrading process temperature on the composition and characteristics of the obtained products was estimated. For the first time, the optimal technological parameters for the implementation of the upgrading process on a zeolite catalyst from the perspective of the production of arctic diesel fuel were determined.

Characteristics of Russian and foreign wire rope lubricants with synthetic thickeners used by Russian steel rope manufacturers are presented. Comparative wear resistance testing results are given for steel ropes lubricated with rope lubricants. The testing have been carried out in accordance with GOST (State Standard) 2387–80 under the simulation of operating conditions by exposure to corrosive environments and temperatures. It has been shown that in the case of a correctly chosen lubricant, the service life of the steel rope can exhibit a multifold increase, whereas in the case an incorrectly chosen lubricant, the durability of the steel rope can decrease to a sufficient extent even with respect to a steel rope operated with no lubricant. [ABSTRACT FROM AUTHOR]

The European Union requirements related to the quality parameters for fatty acid methyl esters (FAMEs) are gathered in the standard EN 14214:2012 + A2:2019 that also includes reference to low-temperature properties. This paper presents studies on the obtaining of modified FAMEs, featuring improved low-temperature properties. Investigated fatty acid methyl esters (FAMEs) were subjected to a solvent dewaxing process with a methyl ethyl ketone and the mixture of methyl ethyl ketone—Toluene. It was found that the application of a process carried out under conditions similar to solvent dewaxing, used as a standard procedure for oils dewaxing and slack waxes of petroleum origin deoiling usually used in refinery industrial installations, allows us to achieve the intended goal. The modification of three different types of FAME by the dewaxing process with MEK-TOL and MEK solvents allows for the improvement of low-temperature properties of the obtained modified FAME, consistent in obtaining reduced cloud points, flow points and CFPP. The tests of fatty acid profiles show a clear increase in the content of glycerides of saturated acids in the separated sludge, as compared to the charges from the dewaxing process, which confirms that the selectivity of the dewaxing process is maintained for the atypical raw material, which are fatty acid methyl esters. [ABSTRACT FROM AUTHOR]

The effect of polymeric modification with the use of butadiene—styrene thermoplastic elastomer (BSTPE) on the low-temperature properties of BND 90/130 bitumen has been studied on a Fraas instrument and a dynamic shear rheometer. The efficiency of BSTPE modification with respect to the dynamic rheological properties of polymer-modified bitumen (PMB) at negative temperatures has been demonstrated. It has been noted that the complex shear modulus and phase angle of PMB samples are lower than for the bitumen samples and there are no signs of dynamic vitrification. [ABSTRACT FROM AUTHOR]

A procedure is described for compounding petroleum diesel fuel and the 180-240°C fraction obtained from a liquid bioproduct from the pyrolysis of plant materials. The physicochemical properties and group chemical composition of the plant matter were studied. We present the physicochemical properties of the diesel fuel mixtures obtained. The permissible concentrations of the biocomponent in the preparation of these mixed biodiesel fuels were established. [ABSTRACT FROM AUTHOR]

As high brittleness limits the application of all epoxy resins (EP), here, it can be modified by high-performance thermoplastic poly(ether nitrile ketone) containing phthalazinone structures (PPENK). Therefore, the influence of different PPENK contents on the mechanical, thermal, and low-temperature properties of EP was comprehensively investigated in this paper. The binary blend of PPENK/EP exhibited excellent properties due to homogeneous mixing and good interaction. The presence of PPENK significantly improved the mechanical properties of EP, showing 131.0%, 14.2%, and 10.0% increases in impact, tensile, and flexural strength, respectively. Morphological studies revealed that the crack deflection and bridging in PPENK were the main toughening mechanism in the blend systems. In addition, the PPENK/EP blends showed excellent thermal and low-temperature properties (−183 °C). The glass transition temperatures of the PPENK/EP blends were enhanced by approximately 50 °C. The 15 phr of the PPENK/EP blends had a low-temperature flexural strength of up to 230 MPa, which was 46.5% higher than EP. Furthermore, all blends exhibited better thermal stability.

Through the long-term aging state of 9()二 matrix asphalt, SBS modified asphalt, extreme cold asphalt, rubber asphalt, low temperature bending beam flow under different low temperature (-12, -18-24 and --30 °C) conditions (BBR) test-analyzes the creep stiffness modulus and creep rate of 4 kinds of asphalts at 6() s with temperature; based on the fractional differential theory, it proves the fractional calculus of viscoelastic behavior of viscoelastic materials, and the fractional derivative viscoelastic model is used to fit the asphalt BBR creep stiffness curve, and the relevant model parameters and physical meaning are determined. At the same time-a physical equation between the 1 ow-temperature creep stiffness modulus S and creep ratemof the asphalt is constructed based on the fractional derivative viscoelastic model. The results show that the BBR tests the relationship between the creep stiffness modulus S and the creep rate m of the four asphalts at 6() s. As the asphalt undergoes glass transition, when the temperature is lower than 一1 8 °C, the four asphalts the creep stiffness modulus S and creep rate m often change abruptly and do not show a significant linear change;the fractional derivative viscoelastic model can more accurately describe the low-temperature performance of asphalt in BBR tests. Model parameters A and a fractional derivative order has physical meaning. A is the low-temperature deformation factor of asphalt. The larger the parameter A, the better the low-temperature crack resistance of the four asphalts. The larger the value of the parameter fractional derivative ord era, the stronger the low-temperature relaxation ability of the 4 types of asphalt, the fractional derivative ord er. The second a is the low-temperature relaxation factor of the asphalt, and the fractional derivative order can well estimate the low-temperature creep rate of the asphalt; based on the fractional derivative viscoelastic model, the asphalt low-temperature creep stiffness modulus S and creep rate m the physical equations between them can be characterized by creep compliance rate J7(t), and by increasing the fractional derivative order a of the model parameter, a larger creep compliance rate 丿'(方)can be obtained to improve the low temperature crack resistance of the asphalt. The variable compliance rate 厂(方)is a good indicator of the low-temperature performance of asphalt. [ABSTRACT FROM AUTHOR]

The Ministry of Defense of the Russian Federation have developed a unique standard for Arctic diesel fuel, which implies attainment of low-temperature indices of diesel fuel below -65°C without additives. Because of its high commercial production, over the time from 2017 through 2020 PAO Slavneft-YaNOS (Slavneft-YaNOS PJSC) prepared experimental and semi-industrial batches of Arctic diesel fuel during several pilot-scale runs for the Ministry of Defense of the Russian Federation. This fuel has now been put into production. [ABSTRACT FROM AUTHOR]

The orientation of Nematic liquid crystal (NLC) and order degree of LC molecules are easily affected by ambient temperature, so it is of great significance to explore the low-temperature properties of NLC materials to improve the low-temperature performance of LC devices. The dielectric and elastic constant of the NLC material 1M10500-000 under the high and low-temperature conditions were obtained by the dual-cell capacitance method, linear fitting method and numerical fitting, and were compared. The dynamic response of the NLC at different temperatures was tested, and the rotational viscosity was calculated. The experimental results show that the dielectric constant is still proportional to the order parameter at low temperature. The elastic constants k11 and k33 and the square of order parameter no longer conform to the proportional relationship at low temperature, and the lower the temperature, the greater the deviation of elastic constants from the proportional relationship. As the temperature decreases, the ratio of k33/k11 changes from 2.62 to 2.71, and the rotational viscosity coefficient changes from 5.66 mPa.s to 177.64 mPa.s. Finally, the transient hysteresis phenomenon at low temperature was proposed and explained by the residual direct current voltage. [ABSTRACT FROM AUTHOR]

The European Union requirements related to the quality parameters for fatty acid methyl esters (FAMEs) are gathered in the standard EN 14214:2012 + A2:2019 that also includes reference to low-temperature properties. This paper presents studies on the obtaining of modified FAMEs, featuring improved low-temperature properties. Investigated fatty acid methyl esters (FAMEs) were subjected to a solvent dewaxing process with a methyl ethyl ketone and the mixture of methyl ethyl ketone—Toluene. It was found that the application of a process carried out under conditions similar to solvent dewaxing, used as a standard procedure for oils dewaxing and slack waxes of petroleum origin deoiling usually used in refinery industrial installations, allows us to achieve the intended goal. The modification of three different types of FAME by the dewaxing process with MEK-TOL and MEK solvents allows for the improvement of low-temperature properties of the obtained modified FAME, consistent in obtaining reduced cloud points, flow points and CFPP. The tests of fatty acid profiles show a clear increase in the content of glycerides of saturated acids in the separated sludge, as compared to the charges from the dewaxing process, which confirms that the selectivity of the dewaxing process is maintained for the atypical raw material, which are fatty acid methyl esters.

Copyright of Roads & Bridges / Drogi i Mosty is the property of Road & Bridge Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The paper presents the results of determining the characteristics and composition of straight-run diesel fuels. In addition, low-temperature properties (cloud point, cold filter plugging point, pour point) the diesel fuels and low-temperature additives blends are studied. The regularities of influence the nparaffins and aromatic hydrocarbons content in the diesel fuel composition on the effectiveness of the low-temperature additive is identified. [ABSTRACT FROM AUTHOR]

In this paper, the possibility of using different amounts of re-recycled (repeated recycled) Reclaimed Asphalt Pavement (RAP) in the asphalt mixture was experimentally investigated. First, a single virgin mixture was prepared and artificially aged to simulate the first generation of RAP to be used for designing the first generation of recycled mixtures. Next, the recycled mixtures were further aged to obtain a second generation of RAP to be mixed for preparing the second generation of recycled mixtures with and without the contribution of a rejuvenator. The fatigue behavior and low-temperature properties of all asphalt mixtures were experimentally investigated based on the cylindrical indirect tensile test (CIDT), Bending Beam Rheometer (BBR) mixture creep stiffness tests, and Semi-Circular Bending (SCB) fracture tests, respectively. Results indicate that re-recycled materials designed with and without rejuvenator show inferior fatigue behavior with respect to the first generation of recycled mixtures while exhibiting better performance than the virgin material. Meanwhile, poorer low-temperature creep properties were observed for the mixture prepared with recycled and re-recycled RAP. Fracture properties comparable with those of the virgin material were obtained only for re-recycled mixtures designed with rejuvenator. The present experimental work provides evidence on the possibility of using re-recycled RAP up to 40% when rejuvenators are included in the mix design. [ABSTRACT FROM AUTHOR]

Supported CoMoS and NiWS catalysts were synthesized on the basis of an Al2O3—SAPO-11 composite support. The acid and texture characteristics of the thus synthesized materials were examined. The morphologies of the active sulfide phase of the catalysts were compared. The kinetic properties of the supported sulfide catalysts in the reaction of hydroisomerization of n-hexadecane and in the hydroprocessing of the diesel fraction were examined. It was shown that it is possible to obtain hydrogenates with improved low-temperature properties in the presence of supported sulfide catalysts containing no noble metals. [ABSTRACT FROM AUTHOR]

The proposed bio-modified rubberized asphalt (BMRA) technology integrates bio-oil and crumb rubber modifications, offering cost savings, waste reuse, improved asphalt performance, and reduced asphalt consumption. Like traditional asphalt, BMRA ages over time due to external environmental factors, impacting its pavement performance. This study examines the alterations in rheological and low-temperature characteristics of BMRA during thermal-oxidative aging. Results indicate that incorporating bio-oil minimizes alterations to the complex modulus and phase angle in aged asphalt. BMRA's crossover modulus significantly surpasses that of unaged rubberized asphalt (RA), showcasing the mitigating effect of bio-oil and crumb rubber on asphalt's rheological properties during aging. BMRA demonstrates comparable or enhanced peak load, fracture displacement, fracture toughness, and fracture energy relative to RA. BMRA's glass transition temperature remains lower than that of other unaged asphalts, signifying enhanced resistance to low-temperature cracking even after aging. Bio-oil, characterized by low molecular weight and abundant light components, counteracts performance deterioration attributed to volatile constituents and destabilization of asphalt's colloid structure during aging. Crumb rubber facilitates the absorption and subsequent release of specific light components, augmenting BMRA's resistance to aging. These findings enhance our understanding of the mechanisms governing the aging resistance and performance of bio-modified rubberized asphalt, thereby supporting the development of sustainable and durable asphalt materials. [Display omitted] • Bio-oil and CR mitigate asphalt deterioration during thermal-oxidative aging. • Bio-oil offsets light components volatility and stabilizes asphalt colloid structure during aging. • Absorption and release of light components by CR enhance asphalt aging resistance. [ABSTRACT FROM AUTHOR]

The process of water-based foaming of bitumen produces binders that can be incorporated in cold recycled asphalt mixes and pavement upper structural layers made of half-warm mix asphalt prepared at 100–130 °C. During the foaming process, cold water and air act on hot bitumen (160–170 °C), which results in the explosive vaporization of water leading to changes in the binder structure. The impact of foaming on the properties of bitumen 70/100 was evaluated by investigating the binder characteristics before and after foaming. Determination of two foaming parameters, maximum expansion and half-life, was followed by measurements of penetration at 25 °C, softening point, Fraass breaking point, and dynamic viscosity at 60, 90, and 135 °C. Rheological and low-temperature tests were also performed before and after foaming bitumen 70/100. The Bending Beam Rheometer method was applied to determine the low temperature stiffness modulus. A DHR-2 rheometer was used to determine the dynamic modulus and phase angle of the tested binder. The Black and master curves before and after foaming were plotted in the 2S2P1D model and the model parameters were analysed. Analysis of the test results confirmed the effects of the foaming process on the basic, low-temperature, and rheological characteristics of the bitumen.

TiNb 2 O 7 , as a promising alternative of Li 4 Ti 5 O 12 , exhibits giant potential as low-temperature anode due to its higher theoretical capacity and comparable structural stability. However, the sluggish electronic conductivity still remains a challenge. Herein, bulk modification of Cu + doping in porous TiNb 2 O 7 microsphere is proposed via a simple one-step solvothermal method with subsequent calcination treatment. The results show that the electronic conductivity is improved effectively due to the reduced band gap after doping, while enhanced lithium-ion diffusion is achieved benefiting from the increased interplanar spacing. Therefore, the optimal sample of Cu 0.06 Ti 0.94 Nb 2 O 7 exhibits a high reversible capacity of 244.4 mA h g -1 at 100 mA g -1 after 100 cycles, superior rate capability, and long-term cycling stability at 1000 mA g -1 at room temperature. Particularly, it can also display good performance in a wide temperature range from 25 to -30 °C, including a reversible capacity of 76.6 mA h g -1 at -20 °C after 200 cycles at 200 mA g -1 . Moreover, Cu 0.06 Ti 0.94 Nb 2 O 7 //LiFePO 4 full cell can deliver a high reversible capacity of 177.5 mA h g -1 at 100 mA g -1 . The excellent electrochemical properties at both ambient and low-temperatures demonstrate the great potential of Cu + -doped TiNb 2 O 7 in energy-storage applications., (© 2023 Wiley-VCH GmbH.)

Copyright of Roads & Bridges / Drogi i Mosty is the property of Road & Bridge Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of China University of Petroleum is the property of China University of Petroleum and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Highlights • Deviations from time-temperature superposition principle were observed. • Specimen were tested in temperatures of 0, −10 and −20 °C for 2400 s. • Deviations appeared usually after around 500 s in temperature of −10 °C. • Appearance of deviations depended on type and grade of bitumen. • "Branching" model is required for better description of creep in low temperatures. Abstract The article presents the observed deviations from the time-temperature superposition principle of asphalt concretes, tested in the bending beam creep test at low temperatures for a long time of loading. In almost all tested asphalt concretes, deviations appeared after 500 s of loading at the temperature of −10 °C. Some types of bitumen presented deviations at other temperatures – usually the harder the grade of the bitumen, the higher was the temperature of appearance of deviation. The article investigates also the impact of the following factors on the described deviations: type of bitumen, assumed time of loading and level of loading. [ABSTRACT FROM AUTHOR]

Abstracts High crystalline Na 2 Ni[Fe(CN) 6 ] particles are synthesized by a new electrostatic spray assisted coprecipitation method. Their structures and electrochemical properties are analyzed by X-ray powder diffraction, scanning electron microscopy and galvanostatic cell cycling and so on. Given its highly stable structure, the optimized Na 2 Ni[Fe(CN) 6 ] cathode shows impressive cycling performance with high retention capacity of 89% after 440 cycles at 1 C and excellent rate capability of 56 mAh g−1 at 25 C. In addition, the optimized Na 2 Ni[Fe(CN) 6 ] cathode achieves superior low temperature performances with retains 87% capacity after 440 cycles at 0 °C and a stable capacity of 54 mAh g−1 can be delivered even at −25 °C after 440 cycles. Such a Na 2 Ni[Fe(CN) 6 ] sample provides a promising cathode for sodium-ion batteries in large-scale storage systems. Highlights • Highly crystalline Na 2 Ni[Fe(CN) 6 ] are prepared by a new ESAC method. • Na 2 Ni[Fe(CN) 6 ] shows superior electrochemical properties at different temperatures. • Na 2 Ni[Fe(CN) 6 ] will be a promising cathode for sodium-ion batteries. [ABSTRACT FROM AUTHOR]

The article considers the feasibility of using jet fuel as a low-temperature additive for diesel fuels. The main physicochemical properties and operational characteristics of straight-run diesel fuel sample, jet fuel sample, and their blends have been experimentally determined. It has been established that the use of jet fuel as a low-temperature additive allows producing summer diesel fuel brands. Moreover, it has been established that the use of jet fuel in combination with a depressant- dispersant additive allows producing interseasonal diesel fuel. [ABSTRACT FROM AUTHOR]

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The tests and analyses presented in the paper are related to the 20/30, 35/50 and 50/70 penetration grade road bitumens as well as the asphalt binders obtained through modification of the 35/50 and 50/70 bitumens. The latter were modified by adding to it 3%, 5% and 7% of the Gilsonite natural asphalt and 15%, 25% and 35% of the Trinidad Epuré Z 0/8 natural asphalt. The aim of the study was to assess the changes in the functional and rheological properties of the road bitumens that were modified by adding to them the Gilsonite and Trinidad Epuré natural asphalts. The modified asphalt binders were subjected to the laboratory simulated short-term and long-term aging, where two methods, designed as part of the Strategic Highway Research Program, were used, i.e. the Rolling Thin Film Oven Test and the Pressure Aging Vessel, respectively. The study of the asphalt binders both those that were subjected to aging and those unaged includes thermal susceptibility (the Penetration Index) and resistance to cracking at low temperatures by tests carried out using the Bending Beam Rheometer. The analysis of the results revealed that the unfavourable impact of the aging process on the asphalt binder properties is limited if a suitable amount of the natural asphalt is used as a modifier.

A major global effort is currently underway to reduce dependence on petroleum products and minimize the impact of their derivatives on the environment. Plant oils are being investigated as a potential source of environmentally favorable lubricants given their combination of biodegradability, renewability and excellent lubrication performance. Low oxidation and thermal stability, poor low-temperature properties and a narrow range of available viscosities, however, limit their potential application as industrial biolubricants. The chemical modification of plant fatty acid structures has great potential for improving the physicochemical and friction-reducing properties of these compounds. This paper presents the thermo-oxidation, friction-reducing and physicochemical properties of a series of diester compounds derived from ricinoleic acid as biolubricant basestocks. The results indicated that among the synthesized ricinoleic acid-based diester compounds, octyl 10,12-dihydroxy-9-behenoxystearate 16 has the lowest pour point (−53.26 °C), while octyl 10,12-dihydroxy-9-octyloxystearate 10 has the highest onset temperature (128.98 °C) and the lowest volatile loss and quantity of insoluble deposits (68.78% and 77.25%, respectively). The friction-reducing results indicate an improvement occurred in the presence of longer mid-chain esters and an increased polarity in the ester functional group. The data indicate that some synthesized derivatives have significant potential as environmentally friendly biolubricant basestocks.

The problems of utilizing diesel fuel produced from oil from Talakan oil field (Sakha Republic, Yakutia) have been considered. The analysis of applying depressor additives has been conducted with the objective of improving low-temperature properties of the produced fuel. [ABSTRACT FROM AUTHOR]

Dewaxing of a diesel fuel (DF) of heavy fractional composition (HFC) in an electric field using Dodiflow-4971 depressants and higher fatty alcohols (HFAs) as process activators is studied. It is shown that dewaxing of DF of HFC allows production of DF with improved low-temperature properties. The yield of dewaxed diesel fuel (DDF) at -15°C reaches 75.8 wt% with cloud-point depression of 17°C; at -5°C, the DDF is 77.8 wt% with 11°C depression. The electric charge of alcohols generated during crystallization and the temperature range of thermoelectric effects where the charge persists have a combined effect on the DF dewaxing indices. The dewaxing and quality indices of the DDF are greater for higher values of these characteristics. It is shown that the effectiveness of HFAs as dewaxing activators increases in the order tetradecanol < hexadecanol < octadecanol < C HFA fraction < C HFA fraction. [ABSTRACT FROM AUTHOR]

Copyright of Baltic Journal of Road & Bridge Engineering (Baltic Journal of Road & Bridge Engineering) is the property of Baltic Journal of Road & Bridge Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Low‐temperature magnetization of hematite within the basal plane has been studied in a collection of natural crystals by means of torque magnetometry. Comparison between the torque curves at room temperature and at 77 K allows identification of a weak ferromagnetic moment constrained within the basal plane at temperatures well below the Morin transition. Annealing the samples produces the expected reduction of the weak ferromagnetic moment, but there is also a relationship between the ferromagnetic moment before and after annealing. Low‐temperature measurements after the annealing experiment reveal the presence of a weak ferromagnetic moment that survives the annealing. This observation suggests the magnetic structure of natural hematite crystals below the Morin transition can still be a carrier of magnetization.

Low-temperature cracking is one of main distresses in asphalt pavements and found to usually occur within fine aggregate matrix (FAM) from the perspective of meso-scale. In this study, the Bending Beam Rheometer was utilized to investigate the low-temperature properties of FAM. Temperature, gradation, asphalt content, and gyration level were designed to be variables included in the BBR test for FAM beams. Absorption, stiffness, and m -value were selected to be evaluation indexes to explore the effect of freeze–thaw cycle. Results show that the virgin beams in FAM I-2 are less likely to crack due to the smallest thermal stress and the largest relaxation rate. Poor and rich asphalt content as well as low- and over-compaction are demonstrated to degrade the freeze–thaw resistance of FAM. The absorption indicates that more air voids in FAM result in more moisture damage, and this trend becomes more significant as the bath temperature goes up. It could be concluded that the BBR is an effective tool to predict and control the cracking possibility of FAM. The tiny air voids lead to greater heaving pressure in FAM, which is remarked as the damage mechanism behind the freeze–thaw action. Warm climate and long-lasting heavy traffic are found to be adverse factors deteriorating the resistance of FAM in seasonally frozen regions. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Harbin Institute of Technology. Social Sciences Edition / Haerbin Gongye Daxue Xuebao. Shehui Kexue Ban is the property of Harbin Institute of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)