Search Results (195)

The plant cuticle is a hydrophobic layer covering the cell wall that protects cells from pathogen invasion and water loss. In this study, we analyzed the cuticles of transgenic Arabidopsis thaliana plants overexpressing the vesicular trafficking small GTPase RabA2b. The RabA2b-overexpressing plants exhibited distinctive structural and chemical modifications in their cuticles, including enhanced hair-like wax crystals and increased accumulation of phenolic compounds such as ferulic acid and coumaric acid, which contribute to cutin cross-linking and reinforcement of the cuticle matrix. These chemical and structural changes were associated with improved barrier function and increased drought resistance. Our findings suggest the involvement of RabA2b in affecting the plant cell’s exterior by altering the cuticle composition and architecture, thereby improving plant tolerance to water deficit. Full article

Phase change materials (PCMs) have emerged as an innovative solution in thermal energy storage and thermal management systems (TMS) owing to their outstanding latent heat of fusion during the phase change process. This study is especially addressed to the battery TMS based on Organic PCMs for fast charging/discharging applications of lithium-ion batteries (LIBs). These fast processes generate excessive heat during operation, degrade battery performance, decrease energy efficiency, and reduce the lifespan and safety of batteries. Organic PCMs exhibit desirable properties, including high latent heat capacity, good thermal characteristics, low cost, and ease of integration. The major challenge for the successful application of organic PCM comprises its low thermal conductivity, which impacts the heat storage and release rates. PCM-based Paraffin Wax (PW) has been designed by including expanded graphite (EG) as a high thermal conductivity additive in high latent heat of paraffin wax. Experiments focused on the effects of heating methods (microwaves/S-type EG composition and conventional electric oven/S’-type EG composition) of expandable graphite on the thermophysical properties of different PW/EG composites. The crystal and chemical structure of the study samples were analyzed by X-ray diffraction and Fourier-Transform Infrared spectroscopy. The battery module created with PW/EG composites were ample examined using charging/discharging experiments at five different C-rates. The effect of current rates on battery surface temperature is investigated in two cases: with PCM cooling and with air cooling. A 20.43% decrease in battery temperature is found at 5C rate with PCM cooling and a maximum reduction in battery charging time of 43.77%. Full article

This study investigates the effects of high-pressure compression molding on the molecular orientation and mechanical properties of biomass-derived aliphatic polyamide (PA11). Tensile fracture strength exhibited a significant increase—up to 2.4 times that of untreated samples—under conditions of 1000 kN and 140 °C. Differential Scanning Calorimetry (DSC) and Wide-Angle X-ray Scattering (WAXS) analyses revealed a temperature- and pressure-dependent shift in crystalline phases, suggesting a transition from α’ to phase. The δ’ phase, formed by high-pressure compression molding, is retained even after cooling to room temperature (i.e., Brill transition was not observed). In addition, polarized optical microscopy (POM) observations further supported the presence of changes in molecular orientation. This enhancement (under conditions of 1000 kN and 140 °C) is primarily attributed to the molecular orientation. However, it is also noteworthy that the formation of the δ’ phase is accompanied by an increase in the degree of crystallinity, and that this δ’ phase is retained even after cooling to room temperature without undergoing a Brill transition. In contrast, at 180 °C, although the degree of crystallinity increased, molecular orientation decreased, resulting in reduced tensile strength. These findings indicate that the mechanical properties of PA11 are governed by a complex interplay among phase transitions, molecular orientation, and crystallization, all of which are strongly influenced by temperature and pressure conditions. These findings demonstrate that high-pressure compression molding is an effective method for enhancing the mechanical properties of PA11 through controlled phase transition and orientation Full article

As a vital appearance quality trait of broccoli, curd-surface wax powder not only affects its commercial value but also plays a key role in plant resistance to abiotic stresses. However, its formation mechanism remains unclear. Using low-wax variety CK (‘QH18’) and high-wax variety T1 (‘QHMS4’) as materials, this study systematically elucidated the molecular mechanism of wax powder formation via physiological indexes, scanning electron microscopy (SEM), targeted metabolomics, and transcriptomics. Determination of fatty acid (FA) content in broccoli flower bud tissue showed a close association between FA content and wax deposition. SEM observation revealed that T1 had significantly denser wax crystals, mainly granular, than CK. Targeted metabolomics identified 25 fatty acids in the two varieties. And the linolenic and palmitic acids, with high content and significant differences, may be key metabolites regulating wax synthesis. Integrated transcriptomics and metabolomics indicated that BolfabG, BolLACS, BolKCS1, BolKCS2 and BolMAH1 genes are involved in wax biosynthesis. Moreover, AP2/ERF-ERF transcription factor (TF)-encoding genes (BolERF018, BolERF1F.1, BolERF1F.2 and BolERF1C) played the primary role in regulating wax biosynthesis, followed by NAC (BolNAC62.1), MYB (BolMYB44), and MADS-MIKC(BolPISTILLATA). These TFs may regulate BolfabG, BolLACS, BolKCS1, BolACOX2 and BolACAA1 to affect linolenic and palmitic acid balance, altering wax precursor synthesis and accumulation, and finally leading to differences in wax morphology and content. This study reveals a “Transcription Factors–Differentially Expressed Genes–Differentially Accumulated Metabolites–Fatty Acids” (TFs-DEGs-DAMs-FA) network, providing a basis for understanding broccoli wax formation. Full article

Glossy appearance is a critical trait that affects the appearance quality and marketability of leafy vegetables, including Chinese cabbage. The glossy trait is primarily associated with cuticular wax. Although several genes involved in cuticular wax biosynthesis have been characterized in Chinese cabbage, the regulatory relationships among them remain unclear. In this study, we identified a glossy mutant, glossy leaf4 (gl4), and cuticular wax crystals in the gl4 mutant were obviously reduced. Genetic analysis indicated that the glossy phenotype in the gl4 mutant appears to be controlled by a single recessive gene. Using a bulked segregant analysis coupled with next-generation sequencing (BSA-seq) and map-based cloning methods, the AtCER2 homologous gene BrCER2 was identified as the candidate gene. BrCER2 was expressed in various tissues, and BrCER2-GFP was localized in the endoplasmic reticulum (ER). Furthermore, BrCER2 could interact with BrKCS6 in the ER, and the expression levels of some wax biosynthesis-related genes were decreased in the gl4 mutant. Our overall results provide insights about the role of BrCER2 in wax biosynthesis through ER localization and interaction with BrKCS6 in Chinese cabbage. Full article

Cuticular wax plays an important role in the quality of kumquat (Fortunella crassifolia Swingle) fruit. In this study, the wax morphology, compositional profile of epi- and intracuticular wax, and crucial gene expression in ‘Rongan’ kumquat (RAK) and ‘Huapi’ kumquat (HPK) were analyzed during fruit development. The results showed that the surfaces of two kumquat fruits were covered with an amorphous wax layer containing a small number of platelets. Compared to RAK, HPK contained more abundant and larger wax crystals during fruit development. In two kumquat fruits, the epicuticular wax and its major compositions consistently displayed significantly higher levels than the intracuticular wax. Additionally, their main wax composition shifted from alkanes in the early developmental stages to triterpenoids at harvest in both layers, while aldehydes were specifically enriched in the epicuticular wax. During the fruit development from 90 to 180 DAF, HPK fruit exhibited significantly higher levels of epicuticular wax and its majority fractions than RAK fruit. Meanwhile, the intracuticular wax contents of HPK from 90 DAF to 150 DAF were significantly higher than those in RAK, with triterpenoids accounting for the largest proportion of this increase. qRT-PCR results indicated that the up-regulation of wax-related genes in HPK was linked to its increased epicuticular wax deposition during the development. Overall, this study provided a comprehensive overview of the morphology, composition, and biosynthesis of cuticular wax in kumquat fruit during development. Full article

The physicochemical, thermal and textural properties of oleogels formed from olive pomace oil and argan oil using carnauba (KW), candelilla (CW) and sunflower (AW) waxes and their combinations (KCW: 50% carnauba + 50% candelilla wax, KAW: 50% carnauba + 50% sunflower wax, CAW: 50% candelilla + 50% sunflower wax) were investigated. The highest mean L* value, peroxide value and time of crystallization formation were found in AW oleogelator. Argan oil + AW had the lowest mean L* value. Sunflower wax differed from the other waxes in terms of major fatty acids, and oleogels containing argan oil and olive pomace oil exhibited a different major fatty acid profile from each other; in particular, there were higher values of oleic acid content in the groups where olive pomace oil was used. It was determined that KW and the oleogels containing KW had higher melting and crystallization temperatures and enthalpy values compared to other waxes. The hardness, adhesiveness, gumminess, cohesiveness and springiness values of the oleogels were affected by the oils and waxes used. The oleogels using sunflower wax were different in terms of texture profile from oleogels formed with carnauba and candelilla waxes. Full article

As a key medium in industry, lubricating oil plays a significant role in reducing friction, cooling sealing and transmitting power, which directly affects equipment life and energy efficiency. Traditional mineral-based lubricating oils rely on non-renewable petroleum, and they have high energy consumption and poor biodegradability (<30%) during the production process. They can easily cause lasting pollution after leakage and have a high carbon footprint throughout their life cycle, making it difficult to meet the “double carbon” goal. Bio-based lubricating oil uses renewable resources such as cottonseed oil and waste grease as raw materials. This material offers three significant advantages: sustainable sourcing, environmental friendliness, and adjustable performance. Its biodegradation rate is over 80%, and it reduces carbon emissions by 50–90%. Moreover, we can control its properties through processes like hydrogenation, isomerization, and transesterification to ensure it complies with ISO 6743 and other relevant standards. However, natural oils and fats have regular molecular structure, high freezing point (usually > −10 °C), and easy precipitation of wax crystals at low temperature, which restricts their industrial application. In recent years, a series of modification studies have been carried out around “pour point depression-viscosity preservation”. Catalytic isomerization can reduce the freezing point to −42 °C while maintaining a high viscosity index. Epoxidation–ring-opening modification introduces branched chains or ether bonds, taking into account low-temperature fluidity and oxidation stability. The deep dewaxing-isomerization dewaxing process improves the base oil yield, and the freezing point drops by 30 °C. The synergistic addition of polymer pour point depressant and nanomaterials can further reduce the freezing point by 10–15 °C and improve the cryogenic pumping performance. The life cycle assessment shows that using the “zero crude oil” route of waste oil and green hydrogen, the carbon emission per ton of lubricating oil is only 0.32 t, and the cost gradually approaches the level of imported synthetic esters. In the future, with the help of biorefinery integration, enzyme catalytic modification and AI molecular design, it is expected to realize high-performance, low-cost, near-zero-carbon lubrication solutions and promote the green transformation of industry. Full article

Oil sands drilling frequently contaminates water-based xanthan gels with highly viscous asphaltenes, collapsing their three-dimensional network and causing barite sag, high fluid loss and poor cuttings transport. Nitrogen-functionalized carbon quantum dots (N-CQDs) were hydrothermally synthesised from citric acid and 1-hexadecylamine and characterised by means of FT-IR, TEM and TGA. The concentration-dependent influence of N-CQDs (0–1.2 wt%) on gel viscoelasticity, microstructure and filtration properties was evaluated through rheometry, API and fluid-loss tests. At 0.01 wt% N-CQDs, the viscosity of the adsorbed oil phase dropped by 50% and the mean droplet diameter decreased from 247.7 µm to <100 µm. Consequently, the xanthan gel exhibited a significant enhancement in its mechanical strength and fluid loss performance. Wax-crystal growth was simultaneously inhibited, lowering the pour point by 6 °C. N-CQDs act as nanospacers that disrupt π-stacking of asphaltenes and hydrogen-bond to the polymer backbone, thereby restoring gel strength and sealing capacity. The work provides a sustainable, low-toxicity route to rejuvenate gel-based drilling fluids contaminated by heavy oil and facilitates their reuse in oil sands reservoirs. Full article

Single-type viscosity reducers often fail to meet the application requirements of specific oilfields for high-viscosity heavy oils. This study focused on Henan heavy oil, systematically investigating the viscosity reduction performances of oil-soluble viscosity reducers, emulsifiers, and their composite systems. Experimental results indicated that the oil-soluble ethylene-vinyl acetate copolymer (EVA) achieved optimal efficiency at a concentration of 500 ppm, with a viscosity reduction rate of 44.2%. Among the screened emulsifiers, acrylonitrile-ethylene-styrene (AES) exhibited the highest viscosity reduction rate (99.9%), which basically complied with relevant industrial application standards. When EVA and AES were compounded, the resulting composite reducer showed a significantly higher viscosity reduction rate than single EVA, and the stability of the formed oil-in-water (O/W) emulsion was further enhanced. The synergistic mechanism was clarified as follows: EVA first disrupts the aggregation of heavy components (resins and asphaltenes) and modifies wax crystal morphology, creating a favorable microfoundation for subsequent emulsification; AES then promotes the formation of stable O/W emulsions, ultimately achieving a “1 + 1 > 2” synergistic viscosity reduction effect. Furthermore, the potential action mechanism of the EVA-AES composite system was verified using multiple characterization techniques. This study provides a valuable reference for the selection and practical application of heavy oil viscosity reducers in oilfield operations. Full article

Pepper (Capsicum frutescens L.) is a globally important vegetable crop whose fruit glossiness serves as a key quality trait influencing consumer preference and market value. This review summarizes the measurement methods, influencing factors, and molecular regulatory mechanisms of pepper fruit surface glossiness, as well as the correlation between post-harvest changes in carotenoid content and fruit surface glossiness, aiming to provide references for the molecular breeding of high-gloss pepper cultivars. Pepper fruit glossiness is primarily determined by cuticle structure and composition. The content and arrangement of cuticular crystals significantly affect the specular reflection and diffuse reflection on the fruit surface. The ordered arrangement of long-chain alkanes enhances the anisotropy of specular highlights, reduces the contrast of diffuse reflection, and forms a high-gloss surface. In contrast, the imbalance of wax components or disordered accumulation of crystals leads to increased light scattering, resulting in a matte phenotype. Furthermore, carotenoid content strongly correlates with L*, a*, and b*, critically influencing fruit color intensity and hue. Currently, there are still several issues in the research on pepper glossiness, including the lack of standardized measurement methods, unclear gene regulatory networks, and unknown pathways related to post-harvest gloss maintenance and environmental responses. In the future, we should promote the combination of multiple technologies to establish unified measurement standards; integrate multi-omics to identify key genes; develop targeted preservation technologies based on the law of fruit gloss degradation; and breed pepper cultivars with high glossiness and good storage performance. Full article

A series of PTT-b-PTMG copolyesters was synthesized via direct esterification followed by melt polycondensation using purified terephthalic acid (PTA), bio-based 1,3-propanediol (PDO), and poly(tetramethylene glycol) (PTMG) of varying molecular weights (650–3000 g/mol). The resulting materials were comprehensively characterized in terms of chemical structure, molecular weight, thermal behavior, phase morphology, crystalline architecture, and mechanical performance using a range of analytical techniques: Fourier-transform infrared spectroscopy (FTIR), ¹H-NMR, gel permeation chromatography (GPC), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), wide-angle X-ray scattering (WAXS), small-angle X-ray scattering (SAXS), dynamic mechanical thermal analysis (DMA), tensile testing, and other standard physical methods. FTIR, ¹H-NMR, and GPC data confirmed the successful incorporation of both PTT-hard and PTMG-soft segments into the copolymer backbone. As the PTMG molecular weight increased, the average sequence length of the PTT-hard segments (L_n,T) also increased, leading to higher melting (T_m) and crystallization (T_c) temperatures, albeit with a slight reduction in overall crystallinity. DMA results indicated enhanced microphase separation between hard and soft domains with increasing PTMG molecular weight. WAXS and SAXS analyses further revealed that the crystalline structure and long-range ordering were strongly dependent on the copolymer composition and block architecture. Mechanical testing showed that tensile strength at break remained relatively constant across the series, while Young’s modulus increased significantly with higher PTMG molecular weight—concurrently accompanied by a decrease in elongation at break. Furthermore, the elastic deformability and recovery behavior of PTT-b-PTMG block copolymers were evaluated through cyclic tensile testing. TGA confirmed that all copolyesters exhibited excellent thermal stability. This study demonstrates that the physical and mechanical properties of bio-based PTT-b-PTMG elastomers can be effectively tailored by adjusting the molecular weight of the PTMG-soft segment, offering valuable insights for the rational design of sustainable thermoplastic elastomers with tunable performance. Full article

Melt-spun PA6/TiO₂ fibers with TiO₂ modified by silane coupling agents KH550 and KH570 at 0, 1.6, and 4 wt% provide a practical testbed to address three fiber-centric gaps: transferable interphase quantification, interphase-resolved indications of compatibility, and a reproducible kinetics–structure–property link. This work proposes, for the first time at fiber scale, a four-phase partition into crystal (c), crystal-adjacent rigid amorphous fraction (RAF-c), interfacial rigid amorphous fraction (RAF-i), and mobile amorphous fraction (MAF), and extracts an interfacial triad consisting of the specific interfacial area (S_v), polymer-only RAF-i fraction expressed per composite volume (Γ_i), and interphase thickness (t_i) from SAXS invariants to establish a quantitative interphase-structure–property framework. A documented SAXS/DSC/WAXS workflow partitions the polymer into the above four components on a polymer-only basis. Upon filling, Γ_i increases while RAF-c decreases, leaving the total RAF approximately conserved. Under identical cooling, DSC shows the crystallization peak temperature is higher by 1.6–4.3 °C and has longer half-times, indicating enhanced heterogeneous nucleation together with growth are increasingly limited by interphase confinement. At 4 wt% loading, KH570-modified fibers versus KH550-modified fibers exhibit higher α-phase orientation (Hermans factor f(α): 0.697 vs. 0.414) but an ~89.4% lower α/γ ratio. At the macroscale, compared to pure (neat) PA6, 4 wt% KH550- and KH570-modified fibers show tenacity enhancements of ~9.5% and ~33.3%, with elongation decreased by ~31–68%. These trends reflect orientation-driven stiffening accompanied by a reduction in the mobile amorphous fraction and stronger interphase constraints on chain mobility. Knitted fabrics achieve a UV protection factor (UPF) of at least 50, whereas pure PA6 fabrics show only ~5.0, corresponding to ≥16-fold improvement. Taken together, the SAXS-derived descriptors (S_v, Γ_i, t_i) provide transferable interphase quantification and, together with WAXS and DSC, yield a reproducible link from interfacial geometry to kinetics, structure, and properties, revealing two limiting regimes—orientation-dominated and phase-fraction-dominated. Full article

Encapsulation of fish oil within oleogels can potentially prevent oxidation and enable its use in food with programmable release within the gastrointestinal tract. Here, we report on the formation of oleogels from two different fish oils—salmon oil (SO) and cod liver oil (CLO)—using different concentrations of either rice bran wax (RBW) or myristic acid (MA) as gelators. The gels were assessed with respect to their structural, thermal, viscosity, digestive, and oxidative properties. Polarized light microscopy (POM) revealed that RBW consistently produced dense, interconnected crystalline networks across both oils, while MA formed larger, spherulitic crystals that were more sensitive to the oil type. This was further supported by time-lapse imaging, showing faster crystal growth of MA in cod liver oil. Viscosity studies indicate that the molecular weight and concentration of gelator, as well as the type of fish oil (SO vs. CLO), significantly impact the shear stability of the oleogels. Thermal and viscosity analyses confirmed that RBW-based oleogels exhibited higher crystallization temperatures and stronger viscoelastic behaviour. Based on oxidative stability measurements—as measured by peroxide value (PV) analysis—encapsulation within oleogels does not lead to significant oxidation of the fish oils and also attenuates further oxidation upon storage. The fish oil oleogels were stable when exposed to either simulated gastric or intestinal fluids (SGF and SIF, respectively), but decomposed after sequential exposure first to SGF and then to SIF. These findings could broaden the range of food products which can be fortified with fish oils. Full article

Vegetable oils structured with natural wax blends have attracted increasing interest due to their tunable crystallization and gelling behavior. This study evaluated the structuring of chia oil (ChO) using low concentrations (1–5%) of a shellac wax (SW) and beeswax (BW) blend in a 1:1 ratio, focusing on physicochemical, viscoelastic, and thixotropic properties. ChO structured with 1% SW/BW formed a weak network with high oil loss, whereas concentrations of 3–5% formed denser networks, resulting in OBC values of 75.6–88.4% and firmness values of 16.9–55.1 g. Structuring with 5% SW/BW significantly reduced peroxide values (p < 0.05), indicating a reduction in oxidative deterioration after oleogelation, while concentrations of 1–3% had no significant effect (p > 0.05). Although induction periods were slightly extended in structured samples, differences across oleogelant concentrations were not statistically significant (p > 0.05). Rheological analysis revealed that 3–5% SW/BW-structured ChO exhibited semisolid gel behavior, characterized by enhanced deformation resistance and thermal stability. Thixotropic recovery tests revealed that structural recovery improved as the deformation amplitude decreased within the linear viscoelastic range, suggesting that thixotropic behavior was influenced by oleogelant concentration. These findings demonstrate the potential of SW/BW-structured ChO as fat alternatives in lipid-based foods that require mechanical resilience, structural recovery, and enhanced oxidative stability, even at low wax levels. Full article