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[Display omitted] • Magnetic field assisted laser-induced plasma micromachining (MLIPMM) was proposed. • MLIPMM induced graphene with longitudinal growth on micro-nano structures. • The MLIPMM exhibited a high contact angle (163.1°) and a low roll-off angle (1.5°). • It has potential applications in lunar for self-cleaning and temperature resistance. High temperature resistant and self-cleaning superhydrophobic flexible film has potential application value in lunar exploration. In this paper, a novel method of magnetic field-assisted ultrafast laser induced plasma was proposed to fabricate strongly superhydrophobic graphene on polyimide film with multi-level micro-nano structure. The longitudinal magnetic field contributed to constrain the induced plasma in the lateral direction so as to form a plasma plume with high temperature and high energy density. The multi-level micro-nano graphene structures with better ordering and superhydrophobicity were fabricated, which had a contact angle of 163.1° and a roll-off angle of 1.5°, as well as hydrophobic C C bond content of 72.82 %. The droplets can achieve obvious bouncing at different heights of 1 cm and 5 cm on surfaces at different angles of 0°, 5° and 10°. The contact angle was still greater than 160° after 25 days of aging treatment and heating at 300 °C for 40 min. The water droplets before and after the heating of the sample can push the dust off the surface, showing excellent high temperature resistance and self-cleaning performance. [ABSTRACT FROM AUTHOR]

Hydrazide-substituted phthalonitrile resin (1e) has been synthesized via nucleophilic substitution reaction of hydrazide-substituted bisphenol (1d) with 4-nitrophthalonitrile to introduce a flexible linking group between rings for low-melting material. The resin was molecularly designed with two flexible hinges of hydrazide functionality with an arm and a low melting point resin system. The resin monomer in Differential scanning calorimetry (DSC) analysis, instead of showing a low melting point, showed a relatively high melting peak (Tm) at 266 °C, due to the formation of a more stable enol form on account of an extended conjugation, which was confirmed by Nuclear Magnetic Resonance (NMR), Fourier Transform Infrared (FTIR), and Ultraviolet (UV) spectra. The monomer was assessed for its thermal, rheological, and curing characteristics. The DSC analysis of uncured 1e showed the onset of curing (Tons) at 269 °C along with curing window of 69 °C. The processing window was found to be ~40 °C by rheological tests. The enthalpy of curing for 1e was found to be 151.5 Jg−1. Thermogravimetric analysis (TGA) of the fully cured polymer (1f) revealed the onset of thermal degradation (Tdo) of 450 °C along with a char yield of 66 wt.% at 800 °C in N2 atmosphere. In air atmosphere multistep degradation was obtained and nil ash yield was found at 600 °C. The limiting oxygen index (LOI) value of the cured polymer (1f) was found to be ̴ 43.9 (estimated by Krevelen's equation). [ABSTRACT FROM AUTHOR]

Copyright of Oilfield Chemistry is the property of Sichuan University, Oilfield Chemistry Editorial Office 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 high-temperature resistance of magnesium phosphate cement (MPC) as an inorganic adhesive for strengthening and repairing building structures has attracted significant attention. In this paper, a pyrophyllite compound magnesium phosphate cement (P-MPC) was prepared. The high-temperature resistance of this material was analyzed through mechanical properties, mass loss rate, microscopic observation, and phase analysis. Results indicate that with increasing pyrophyllite content, the compressive strength retention rate of MPC gradually in creased at elevated temperatures. At 800 °C, the strength retention rate of MPC with 12% pyrophyllite content was 20%, exceeding 6% of the blank control group. Phase composition analysis revealed that the decomposition of hydration product struvite was a key factor leading to the decrease in compressive strength of MPC. Thermogravimetric analysis indicated that the mass loss rate of MPC decreased gradually with increasing pyrophyllite content. Backscattered electron spectrometer (BES) analysis of the microstructure and elemental composition of the blank control group and the experimental group with 12% pyrophyllite content at 200 °C and 800 °C showed that the pyrophyllite maintained good integrity with MPC at high temperatures, indicating that this silicate material can effectively combine with MPCthereby improv its high-temperature resistance. [ABSTRACT FROM AUTHOR]

The reverse water‐gas shift (RWGS) reaction offers an effective method for mitigating CO2 emissions. Due to its affordability and physicochemical stability, iron has garnered significant attention as a potential catalyst for RWGS. The incorporation of nickel and copper promoters can enhance CO2 conversion and CO selectivity in Fe‐based catalysts. This study focuses on modifying the strength of the Strong Metal‐Support Interaction (SMSI) through particle size optimization. Doping Cu into NiFe‐based catalysts restricts particle size, which influences the curvature of the Ni0@FeOx interface. This curvature enhances the electron coupling between Ni0 and FeOx, promoting the formation of a denser and thicker Ni0 and FeOx layer. This results in a nearly 90% increase in the CO2 reaction rate during the sintering resistance test by anchoring Ni0 and facilitating electron transfer to active sites. Such morphological evolution improves high‐temperature resistance to sintering during RWGS. © 2024 Society of Chemical Industry and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract [Objective] The desert plant Karelinia caspica has strong heat tolerance. The aim is to clone and study the heat-tolerant genes of K . caspica, and apply them to economic crops such as cotton to enhance heat resistance. This provides a theoretical basis and genetic resources for molecular breeding of heat-tolerant crops. [Methods] KcPIF4 gene was cloned and bioinformatics analysis was performed. Subcellular localization of the protein was analyzed through transient expression in tobacco. qRT-PCR was used to analyze the expression of KcPIF4 in roots, stems, and leaves of K . caspica seedlings at different time under 45 ℃ treatment. Changes in phenotype of Arabidopsis overexpressing KcPIF4 at 45 ℃ were observed, and relevant physiological and biochemical indicators were measured. [Results] The full length CDS of KcPIF4 is 1 593 bp, encoding 530 amino acids and containing a bHLH conserved domain. The motifs showed differences compared to homologous proteins from various plants. The protein was localized at the membrane of the guard cell of stomata. qRT-PCR showed that the expression of KcPIF4 in K . caspica leaves was first increased and then decreased, and increased again with prolonged treatment time, reaching its peak at 240 min, 4.4 times higher than the control. Overexpression of KcPIF4 in Arabidopsis produced less chlorosis and wilting in the leaves compared to the wild type at 45 ℃, with higher level of CAT, SOD, POD, chlorophyll a, chlorophyll b, and carotenoids, as well as lower level of MDA content and relative conductivity compared to the wild type. [Conclusion] KcPIF4 functions in tolerance-responseadaptation to high temperature stress, enhancing Arabidopsis tolerance to high temperature. This result suggests that the protein has high temperature resistance.

ITO thin films exhibit superior optical characteristics. However, their electrical properties are somewhat less optimal, and they demonstrate limited tolerance under high-temperature conditions. These limitations significantly constrain their potential applications in the domain of optical and electronic devices. In this study, ITO thin films with a thickness of 20 nm were prepared on a flexible Mica substrate. The film has an atomic-level flat surface, high optical transparency (around 85 %), and low resistivity. The stability of the film's surface chemical structure in high-temperature applications was confirmed through XPS characterization. Furthermore, the ITO/Mica flexible thin film demonstrates exceptional durability and recyclability, retaining its optical and electronic properties under a high bending radius of 5 mm and 1000 bending cycles. It is particularly noteworthy that the film's maintenance of good structural and electrical stability (sheet resistance stabilized at 35∼37.5 Ω/sq) under bending cycles at high-temperature (up to 800 °C) conditions, which is crucial for high-temperature resistance in commercial and industrial applications. This study will provide an important experimental basis for the further development and application of ITO thin films in flexible transparent electronic devices with high temperatures and low energy consumption. [ABSTRACT FROM AUTHOR]

In this work, a new type of high-entropy ceramic powder (La 0.2 Ce 0.2 Gd 0.2 Er 0.2 Sm 0.2) 2 Zr 2 O 7 was synthesized by sol-gel method and high-temperature sintering (1000 °C) method. Combing (La 0.2 Ce 0.2 Gd 0.2 Er 0.2 Sm 0.2) 2 Zr 2 O 7 and glass powder to prepare high-entropy ceramic-glass composite coating. The composite coating exhibits excellent seawater corrosion resistance and high-temperature resistance performance. The impedance values of composite coating are 2.36 × 106 Ω cm2 in 3.5 % NaCl solution for 24 h. The high-entropy ceramic-glass composite coating could withstand the high temperature of 600 °C for 30 days and remains tight and intact with stainless steel without falling out. This work shows that the (La 0.2 Ce 0.2 Gd 0.2 Er 0.2 Sm 0.2) 2 Zr 2 O 7 -glass composite coating can provide long-term high-temperature and seawater corrosion protection for stainless steel and has good application prospects in the field of marine corrosion protection. [ABSTRACT FROM AUTHOR]

More and more deep, low permeability and high temperature oil and gas reservoirs have been discovered by exploration, however, there are fewer types of fracturing fluids that can be used for production enhancement and modification of such reservoirs. Due to their high viscoelasticity, water-soluble hydrophobic polymers have been widely used as thickeners of working fluids for drilling and oil repulsion, and have also been applied in fracturing, but their weak temperature resistance limits their applicability to reservoirs, and their high initial viscosity makes them difficult to be formulated in the field. To address the above problems, this paper successfully prepared a high temperature resistant thickener PAAQ based on free radical polymerization method, which is used for fracturing and production enhancement in deep low permeability and high temperature oil and gas reservoirs. The experimental results show that PAAQ has good thickening, temperature resistance, shear resistance, viscoelasticity and other properties, and is suitable for fracture acidizing in carbonate formations.The thickening mechanism of PAAQ is the formation of a three-dimensional network structure by polymer molecular aggregation and chelation of the betaine side chains with calcium ions.The storage modulus G' of PAAQ solution is always higher than that of energy dissipation modulus G"; k<1.0·10-3 m/min1/2 , R <1.5·104 m/min, V0 <5.·10 m-23/m2; the settling rate of the ceramic particles was lower than 0.48 cm/min; when the NaBO3 dosage was 0.1%, the viscosity of the fracturing fluid was reduced to 30 mPa∙s at 110 min, which indicated that the fracturing fluid system had good sand-carrying performance, filtration-loss control ability and gel-breaking performance. This paper provides a theoretical basis for the synthesis and application of high-temperature resistant polymer fracturing fluids. [ABSTRACT FROM AUTHOR]

To address the challenge of inadequate structural strength in the spatial framework of oil-based drilling and completion fluids under ultra-high temperatures and extended durations, which leads to poor solid phase carrying and suspension capabilities, two key materials were developed: an amphiphilic multiblock polymer viscosifier (HT-TQ) and an oil-soluble small molecule gelling agent (HT-CB). HT-TQ effectively enhances the yield point and low shear rate viscosity of the base emulsion, while HT-CB significantly improves the static yield point. Sepiolite fibers were selected as suspension enhancers, which, in synergy with HT-TQ and HT-CB, further improve the rheological properties of the emulsion after ultra-high temperature rolling and strengthen the spatial framework structure. Using these three suspension stabilizing materials as the core, optimal additives were selected to construct a highly stable oil-based drilling fluid system suitable for ultra-high temperatures. This system withstands temperatures up to 240℃, maintains a viscosity retention rate greater than 78% after five days of continuous ultra-high temperature rolling, with a yield point greater than 5 Pa and LSYP greater than 3 Pa, and exhibits excellent rheological properties under high temperature and high pressure. Additionally, by using compounded barite as a weighting material, a stable oil-based completion fluid system was developed, which withstands temperatures up to 240 ℃ and remains homogeneous without hard settling after ten days of static exposure to ultra-high temperatures, with a settlement degree less than 1.2 N. These research findings provide technical support for efficient drilling and completion fluids in deep and ultra-deep oil and gas reservoirs. [ABSTRACT FROM AUTHOR]

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Copyright of Journal of Railway Science & Engineering is the property of Journal of Railway Science & Engineering Editorial Office 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.)

Compared to Pyropia haitanensis, a species of seaweed cultured in southern China, Pyropia suborbiculata exhibits stronger high-temperature resistance but its round shape is unsuitable for commercial culture. To address this, researchers have isolated several long-type mutants and strains from wild-type strain of P. suborbiculata using artificial mutagenesis. However, their growth rates are still relatively slow. In this study, the blades of a long-type strain (PS-5) were irradiated with 60Co-γ rays to determine the optimal mutagenic dose of 1200 Gy. Subsequently, a new strain with fast growth, PS-M4, was selected from its progeny based on growth rate. After 60 days of culture at 23 ℃, the average length and wet weight of PS-M4 blades were 76.3 cm and 1.3 g, respectively, which were 58.2% and 38.9% higher than those of PS-5. Both PS-M4 and PS-5 maintained normal cellular morphology without any dead cells after being cultured for 30 days at 23 ℃ followed by 30 days at 30 ℃, while the traditional cultivated strain (Ph-WT10) of P. haitanensis showed more cell pigment dispersion and death. After 14 days of culture at 30 ℃, the survival rates of conchospore germlings of PS-M4 and PS-5 were 70.6% and 66.5%, respectively, with no significant difference between them, but 133.8% and 120.2% higher than that of Ph-WT10. At this time, over 80% of the conchospore germlings of both PS-M4 and PS-5 contained more than 9 cells, while all the conchospore germlings of Ph-WT10 had only 1-4 cells. After 45 days of culture at 23 ℃, the contents of chlorophyll a and total phycobiliprotein of PS-M4 blades were 6.6 and 61.7 mg g-1, respectively, which were 12.3% and 14.9% higher than those of PS-5. The average thickness of PS-M4 was 30.5 μm, which was 16.6% thinner than that of PS-5. In terms of total released conchospores over 10 consecutive days, PS-M4 reached up to 293.6×104 per shell, which was 3.3 times that of PS-5. In summary, the new strain PS-M4 of P. suborbiculata has shown significant improvements in blades growth, quality, and released conchospores, while its conchospore germlings and blades exhibited superior high-temperature resistance compared to traditional cultivated strain of P. haitanensis, making it a promising candidate for commercial cultivation. [ABSTRACT FROM AUTHOR]

Copyright of Oilfield Chemistry is the property of Sichuan University, Oilfield Chemistry Editorial Office 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.)

Polymer-derived ceramic aerogels are promising materials for thermal insulation and microwave absorption in harsh environments because their microstructures can be controlled at the molecular level. Silicon oxycarbide (SiOC) aerogels are considered as potential high-temperature electromagnetic wave (EMW) absorbers, but their application range is limited by complex preparation process and unsatisfactory microwave-absorption performance. This paper reports a new SiC nanowire/SiOC composite aerogel (SCA) synthesized through the sol–gel process, environmental pressure drying, and high-temperature treatment. The SCA performance is adjusted by controlling the ratio of SiC nanowires, obtaining low thermal conductivities (0.04–0.042 W m−1 K−1) and excellent mechanical properties (4.37–5.45 MPa). Increasing the SiC nanowire content gradually increases the EMW absorption capacity of SCA. The optimal reflection loss is −53.64 dB and the effective absorption bandwidth is 3.88 GHz, substantially higher than that of SiOC aerogels. This high performance is mainly attributable to the appropriate impedance matching characteristics and strong polarization loss ability. Moreover, the performance of the composite aerogels was retained after long-term treatment in an air environment at 800 °C. SCA also exhibits excellent high-temperature insulation and flame retardancy. Owing to its light weight, strong microwave-absorption ability, good thermal insulation performance, and oxidation resistance, SCA is a highly promising alternative material for use in extreme environments. [ABSTRACT FROM AUTHOR]

During the drilling process, high-temperature environments can cause the performance of traditional drilling fluids to decline, affecting drilling efficiency and environmental protection. To address this issue, this study added polymetallic hydroxide to anti-temperature and environmentally protective drilling fluid treatment agents, verifying its performance through linear expansion experiments, anti-expansion experiments, mud ball experiments, and thermogravimetric analysis.The experimental results indicate that at 20 minutes, the expansion rate of bentonite is 44.2% in water and 22.3% in KCl, and at 120 minutes, the expansion rate is 70.4% in water and 50.4% in KCl. When mixing different polymetallic hydroxides with bentonite clay, M1-Fe exhibited the lowest swelling among Fe-doped polymetallic hydroxide samples, with rates of 13.3% at 20 minutes and 22.7% at 120 minutes. Among Cu-doped samples, M2-Cu showed the lowest expansion, at 15.9% at 20 minutes and 25.3% at 120 minutes. For Zn-doped samples, M3-Zn had the lowest expansion rates, at 16.5% at 20 minutes and 27.3% at 120 minutes.The results demonstrate that Fe-doped polymetallic hydroxide samples exhibit excellent swelling inhibition and thermal stability at high temperatures. These samples significantly improve the high-temperature stability and environmental performance of drilling fluids, showing great potential for widespread use in high-temperature drilling. [ABSTRACT FROM AUTHOR]

High temperature resistant copol)-mrr thickcncr(l/f) was prepared by free radical pol)-mrrization using monomers such as N・nnylformamide(NVE), divinylbrnzcnc(DVB), an

Copyright of Modern Food Science & Technology is the property of Editorial Office of Modern Food Science & 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.)

AbstractWith 2-acrylamido-2-methylpropanesulfonic acid (AMPS), YX-1 (a monomer containing an amide group) as the main chain, DX-2 (a monomer containing a hydrophobic group), N-vinylpyrrolidone (NVP) as the side chain, the high temperature resistant suspension stabilizer for spacer was prepared by free radical aqueous solution polymerization and characterized. The structure was characterized by fourier transform infrared (FTIR) spectroscopy and thermogravimetry-differential thermal analysis (TG-DTA), which proved that the synthesized product was the target product. The performance of the copolymer was evaluated. The experimental results showed that it could be used in the spacer fluid at 30 ∼ 210 °C, and its sedimentation performance could also meet the requirements in the spacer fluid system containing saturated brine. In order to explore the mechanism of the polymer, the polymer solution was tested by six-speed rotational viscometer, pyrene fluorescence probe test, environmental scanning electron microscopy (ESEM) test, and the isolation solution containing the copolymer was tested by Zeta potential test and X-ray diffraction (XRD). Based on the above test results, it is shown that the suspension stabilizer synthesized in this paper has the characteristics of thickening, physical plugging, chemical and physical adsorption, which can effectively ensure that the spacer fluid has excellent suspension performance at high temperature. [ABSTRACT FROM AUTHOR]

As drilling wells continue to move into deep ultra-deep layers, the requirements for temperature resistance of drilling fluid treatments are getting higher and higher. Among them, blocking agent, as one of the key treatment agents, has also become a hot spot of research. In this study, a high temperature resistant strong adsorption rigid blocking agent (QW-1) was prepared using KH570 modified silica, acrylamide (AM) and allyltrimethylammonium chloride (TMAAC). QW-1 has good thermal stability, average particle size of 1.46 mm, water contact angle of 10.5°, has a strong hydrophilicity, can be well dispersed in water. The experimental results showed that when 2 wt% QW-1 was added to recipe A (4 wt % bentonite slurryþ0.5 wt% DSP-1 (filtration loss depressant)), the API filtration loss decreased from 7.8 to 6.4 mL. After aging at 240 °C, the API loss of filtration was reduced from 21 to 14 mL, which has certain performance of high temperature loss of filtration. At the same time, it is effective in sealing 80-100 mesh and 100-120 mesh sand beds as well as 3 and 5 mm ceramic sand discs. Under the same conditions, the blocking performance was superior to silica (5 mm) and calcium carbonate (2.6 mm). In addition, the mechanism of action of QW-1 was further investigated. The results show that QW-1 with amide and quaternary ammonium groups on the molecular chain can be adsorbed onto the surface of clay particles through hydrogen bonding and electrostatic interaction to form a dense blocking layer, thus preventing further intrusion of drilling fluid into the formation [ABSTRACT FROM AUTHOR]

A novel fluorinated diamine monomer (FPMDA ) was synthesized from p-fluorobenzaldehyde and 2, 6-dimethylaniline, and then reacted with pyromellitic anhydride to obtain a fluorinated polyimide (FPI). The structures of the synthesized FPMDA diamine monomer and polyimide were characterized by FTIR, nuclear magnetic hydrogen spectroscopy, and mass spectrometry (MS) ;the thermal properties of the polyimide film were characterized using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The results showed that FPI has excellent solubility in solvents such as DMF, NMP, and THF. FPI also shows good thermal stability, under nitrogen environment, with thermal decomposition temperature Td5% of 550 °C, Td10% of 580 °C, and char yield of 58.7% at 1 000 °C, its glass transition temperature is greater than 400 °C . [ABSTRACT FROM AUTHOR]

To achieve prolonged reaction and deep penetration in high-temperature and deep wells in carbonate reservoirs, this study innovatively applies the titanium ion slow-release principle. A crosslinking agent, OAC-1, which can crosslink organic acids under high-temperature and high-concentration hydrochloric acid conditions. This has resulted in a high-temperature, deep-penetrating organic delayed crosslinking acid composite system, and evaluated its temperature resistance, shear resistance, gel breaking, filter loss reduction, and sand-carrying capacity. The results showed that the crosslinking could be delayed for 198 s, and the viscosity remained above 55 mPa ⋅ s for 100 min at 150 °C and 170 s-1 shear rate, it has good delayed crosslinking and heat resistance and shear resistance. [ABSTRACT FROM AUTHOR]

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This work aims to investigate the high-temperature resistance and the thermal insulation of alumina aerogels at high temperatures. Alumina aerogels were prepared by the sol-gel method plus supercritical drying using aluminum isopropoxide as the precursor,ethanol as the solvent,and glacial acetic acid as the catalyst. The obtained alumina aerogels were then heat-treated at different temperatures (25,150,250, 300,500,600,850,1 000 and 1 200 °C) for 6 h. The effects of the heat treatment temperature on the phase composition,microstructure, pore structure and specific surface area of the alumina aerogels were studied by FT-IR, XRD, TGA, DSC, SEM, TEM and BET. The results show that: (1) with the increasing heat treatment temperature, the prepared alumina aerogels undergo phase transition; when the temperature is 600 °C,the sample mass hardly changes; (2)when the temperature is 850 °C,the prepared alumina aerogel stiil maintains a three-dimensional porous network skeleton structure,the average pore size is stiil less than 69 nm (the free path of air molecules),and there is no obvious macropore;(3)the specific surface area of the prepared alumina aerogel is 458 m² • g-1 at room temperature,321 m² • g-1 after heat treatment at 850 °C, and 102 m² • g-1 after heat treatment at 1 000 °C. [ABSTRACT FROM AUTHOR]

Copyright of Oilfield Chemistry is the property of Sichuan University, Oilfield Chemistry Editorial Office 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 Oilfield Chemistry is the property of Sichuan University, Oilfield Chemistry Editorial Office 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.)

In the development of ultra-deep wells, extremely high temperatures can lead to inefficiency of additives in drilling fluids. Hence, there is a need to prepare additives with a simple preparation process and good effects at ultra-high temperatures to ensure stable drilling fluid performance. In this study, a high temperature resistant filtration loss polymer (LY-2) was prepared using γ-methacryloyloxypropyltrimethoxysilane (KH570), N,N-dimethylallyl ammonium chloride (DMDAAC), sodium p-styrenesulfonate (SSS), and β-cyclodextrin (β-CD). The impact of the different monomer ratios on particle size, rheology, and filtration performance was systematically investigated. Infrared spectroscopy afforded the structural features. Thermogravimetric Analysis detected the temperature stability, and scanning electron microscopy characterized the polymer micromorphology. LY-2 was completely decomposed at a temperature above 600 °C. Experiments showed FLAPI of the drilling fluid containing 3% LY-2 aged at 260 °C/16 h was only 5.1 mL, which is 85.4% lower compared to the base fluid. This is attributed to the synergistic effect of the polymer adsorption through chemical action at high temperatures and the blocking effect of carbon nanoparticles on the filter cake released by cyclodextrin carbonization at high temperatures. Comparing LY-2 with commercial filter loss reducers shows that LY-2 has excellent temperature resistance, which exhibited five times higher filtration performance and relatively low cost, making it possible to be applied to ultra-high temperature drilling operations in an industrial scale-up. [ABSTRACT FROM AUTHOR]

This paper investigates the high temperature resistance performance and mechanism of potassium-activated blended precursor geopolymer with silica fume. The failure morphology, volume, and mass loss, compressive strength deterioration, hydration production, and pore structure are measured and analyzed. The results show that introducing slag into fly ash-based geopolymer could greatly improve the 28 d compressive strength but reduce the thermal stability. In contrast, the partial substitution of fly ash by metakaolin contributes to excellent high temperature resistance with slightly enhanced 28 d compressive strength. After being exposed at 800 °C, the residual compressive strength of F7M3 remains at 37 MPa, almost 114% of the initial ambient-temperature strength. An appropriately enlarged silica fume content in geopolymer results in increased compressive strength and enhanced thermal stability. However, an excessive silica fume content is detrimental to the generation of alkali-aluminosilicate gels and ceramic-like phases and thus exacerbates the high temperature damage. [ABSTRACT FROM AUTHOR]

Gel plugging agents have become one of the preferred methods for plugging in complex and severe loss conditions during drilling due to their good adaptability to loss channels. To address the common issue of poor temperature resistance in gel-based plugging agents, high-temperature-resistant gel plugging materials were synthesized through the molecular design of polymers, modifying existing agents. Based on the temperature and salt resistance of the aqueous solution of an acrylamide (AM)/N-vinylpyrrolidone (NVP) binary copolymer, temperature-resistant monomer sodium styrene sulfonate (SSS) was introduced and reacted in a polyvinyl alcohol (PVA) aqueous solution. Using ammonium persulfate (APS) as an initiator and crosslinking with N,N-methylenebisacrylamide (MBA), a gel plugging material resistant to 140 °C was synthesized. The structure, thermal stability, water absorption and expansion, and plugging performance of the gel were studied through hot rolling aging, thermogravimetric analysis, infrared spectroscopy, electron microscopy scanning, sand bed experiments, and drag reduction experiments. The results show that the gel material has good thermal stability and water absorption and expansion at 140 °C, and its temperature-resistant plugging performance is excellent, significantly slowing down the loss rate of drilling fluid. This provides a basis for the further development of gel materials. [ABSTRACT FROM AUTHOR]

Anticorrosion and friction-reducing of thermal pipelines are of great significance in the field of heating. A new type of friction-reducing, wear-resistant and heavy-duty anticorrosive coating for thermal pipeline was prepared by using modified epoxy resin, fluoropolymer, anticorrosive pigment and filler, amine curing agent and so on. The performance of the coating was analyzed by differential scanning calorimeter, salt spray test, high temperature boiling, electrochemical impedance analysis, surface contact angle analysis, surface roughness analysis and the friction reduction performance of the coating was evaluated through actual engineering projects. The prepared friction-reducing and wear- resistant coating has good anticorrosive performance, mechanical strength, smooth coating surface, low surface energy and excellent hydrophobicity. It can significantly reduce the friction resistance between water and pipeline during transportation, improve the heating and heat transfer efficiency (more than 30 % in average) and show significant economic benefits. [ABSTRACT FROM AUTHOR]

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Light-weight composite materials with multifunction are widely used on aircrafts, antennas and wind turbines. Its anti-icing/de-icing is still a great challenge due to its poor heat transmission and low heat resistance. To address these issues, a novel electrothermal sandwich composite (NESC) was prepared by hot pressing an electrothermal film into load-bearing composite materials. By optimizing the ingredient of boron nitride nanoparticle, the heat diffusion rate was improved by 86 %, saving ∼14 % of energy consumption for complete anti-icing in dynamic icing conditions compared to samples without thermal conductivity enhancement. Furthermore, high electromagnetic transmittance up to 80 % of NESC was ensured through electromagnetic design. Besides the high-efficient and electromagnetic compatible anti-icing performance, NESC also performs high resistance to acid/alkali, abrasion and impact, good heating uniformity, stable photothermal effect, and potential of large-area manufacture. This paper presents a promising solution for durable, multi-functional, compatible, and energy-saving composites for anti-icing and de-icing.

This is an article in the field of ceramics and composites.To explore the feasibility of using coal waste to replace cement for concrete preparation, the activated coal slag powder and coal gangue powder were used to replace cement at a ratio of 0%, 10%, 20%, 30%, and 40% to prepare concrete samples and prepare concrete samples. The slump, compressive strength, flexural strength and high-temperature performance were tested, and the results show that: as the substitution ratio increases, the slump, compressive strength and flexural strength all increase first and then decrease; The optimal substitution ratio is 20%～30%. The early strength growth rate of the activated coal slag powder sample is large; while the long-term strength growth rate of the activated coal gangue powder sample is large. When the water-cement ratio=0.45, the compressive strength of the sample increases first and then decreases with the increase of temperature, and reaches the maximum at 100 ℃; when the water-cement ratio=0.5, the compressive strength of the concrete sample increases with the temperature; the hydration cement structure in the interface area of the activated coal slag powder sample is the most, followed by the control group, and the activated coal gangue powder sample is the least. With the increase in temperature, the pores and cracks on the surface of the sample increased significantly and the degree of fracture of the damaged surface gradually increased.

In light of escalating global climate change concerns and the pressing need to address industries with high carbon emissions and pollution, enhancing the preparation of phenol-formaldehyde epoxy resins has emerged as a critical research focus. This study seeks to fabricate waterborne phenolformaldehyde epoxy resins with superior performance by investigating pivotal factors influencing their properties and refining preparation methods. Utilizing tetrabutylammonium bromide as a phase transfer catalyst, the phenolformaldehyde epoxy resins are synthesized via a two-step alkalization process. Subsequent etherification reactions involve modifying the phenolformaldehyde epoxy resins using cationic modifier diethanolamine (DEA) and anionic modifier sodium p-amino benzenesulfonate, resulting in waterborne phenol-formaldehyde epoxy resins. Subsequently, in situ synthesis is employed to produce nanoscale silica (SiO2) modified waterborne phenol-formaldehyde epoxy resins. The findings reveal that when the ratio of n1 to n2 falls within the range of 1/3.25 to 1/3, the emulsion displays a moderate particle size and maintains stable storage. Furthermore, an increase in DEA dosage leads to a particle size of less than 324 nm when the ratio of n1 to n2 exceeds 1/3, indicating stability. Moreover, optimal stability and prolonged storage lifespan are achieved when the nano SiO2 content is approximately 1.5%. This study contributes by synthesizing high-quality waterborne phenol-formaldehyde epoxy resin emulsions through optimized methods. The research findings offer a theoretical foundation for this domain and support the practical application of low-carbon and environmentally friendly concepts in the coatings industry. [ABSTRACT FROM AUTHOR]