FUEL
·
2022
·
IF 8.035
Songpeng Cheng,Liangcheng An,Zhenling Li,Suli Liu,Junmin Lv,Subing Fan,Tiansheng Zhao
The products with higher carbon numbers from Fischer-Tropsch (F-T) synthesis are very complex and hard to directly be analyzed on GC due to their very high boiling point. In this work, the qualitative and quantitative analytical method for refined F-T wax samples with C 7 to C 38 was established on GC–MS. All components were well separated, qualified and quantified. The analytical errors were less than ±2 % and the errors of recovery experiments were less than ±5 %. Thereafter, this method was successfully applied in GC analysis with errors less than ±0.75 % and the analytical method on GC was also built, which will provide a more convenience way in analysis of refined F-T wax samples. Based on the obtained analytical conditions and the relative calibration factors of paraffins, the qualitative and quantitative method for the cracking products from refined F-T wax was further built according to a similar method by using simulated samples with the conversion from 5 % to 80 %. The thermal cracking of F-T wax 5# was performed and the content of LAOs in liquid mixtures reached over 50 % at 650 °C. This study simplifies the previous analysis methods which can only be completed by using a variety of standard methods and provide convenience for analysis of refined F-T wax from coal-to-liquid plant.
研究领域:
化学工程
·
分析化学
·
石油化学
✓ 已验证
产品关联
DOI
高影响因子
PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY
·
2023
·
IF 4.7
Jia Lin,Guoqing Yue,Kang Xiao,Deqing Yang,Xuxing Hao,Minlin Zheng,Pumo Cai,Qing'e Ji
Spinetoram wax-based bait station (SWBB) is a maintenance-free, long-lasting, and eco-friendly management measure for Bactrocera dorsalis . However, the impacts of low-concentration spinetoram on B. dorsalis have not yet been determined. Therefore, our study aimed to determine the impacts of low-concentration SWBBs on the biology, demographics, detoxifying enzymes , and gut microorganisms of B. dorsalis . Our results showed that low-concentration SWBBs posed dose-dependent effects on the lifespan and fecundity of B. dorsalis adults. Both the LC 10 and LC 30 treatments significantly reduced the fecundity, while only the latter led to significant deleterious effects on the longevity of adults. Transgenerational bioassays revealed that exposure to LC 30 significantly affected the development period of larvae and pupae as well as the livability of pre-adult stage of the progeny. However, except for the ovipositional period, no significant effects on the biological traits of F 1 adults were observed. In terms of the F 1 demographic parameters, dose-dependent effects were observed. Moreover, both the LC 10 and LC 30 treatments significantly extended the mean generation time, while the latter remarkably decreased the finite and intrinsic rates. Additionally, the significant induction of CarE activity by the LC 10 and LC 30 treatment was maintained until 24 and 48 h respectively. The CYP450 O -deethylation activity in the LC 30 treatment was significantly enhanced at 24 and 48 h intervals when compared to the control. Regarding the intestinal bacterial community , after B. dorsalis adults were exposed to low-concentration SWBBs, the relative abundances of Providencia and Vagococcus were significantly increased, whereas those of Lactococcus and Brachyspira experienced a significant decrease. The obtained results are expected to serve as a foundation for the application of spinetoram in “lure-and-kill” strategies against B. dorsalis.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENERGY & FUELS
·
2019
·
IF 3.021
Huiyong Xue,Jinjun Zhang,Shanpeng Han,Mengran Sun,Xiaohan Yan,Hongying Li
Asphaltenes, as the most polar component of crude oils, may interact with wax molecules during the wax crystallization, thus changing wax precipitation characteristics and wax crystal structure and affecting the gelation behavior of crude oils. In the present work, waxy model oils of variable asphaltene contents (0–0.20 wt %) were prepared in order to systematically examine the effect of asphaltenes on the wax precipitation characteristics and the gelation behavior of waxy oils and to look into the structure and the surface electrical properties of wax crystals formed in oils of different asphaltene contents. By means of differential scanning calorimetry and multiple rheometries, it was found that asphaltenes play a significant role in inhibiting the precipitation of wax crystals and delaying the gelation, as well as in weakening the strength of the gel structure. It was observed by polarized optical microscopy that as the asphaltene content increases, the size of wax crystals gradually decreases, and the shape of wax crystals transforms from rodlike into elliptical. Furthermore, both the average aspect ratio and the average perimeter of wax crystals decrease, while the boundary box fractal dimension increases, demonstrating that the morphology of wax crystals becomes more complex. Based on the X-ray diffraction (XRD) pattern, the grain size obtained with the Scherrer equation presents a descending trend with the increase of asphaltenes. It could be inferred that the reduction of grain size is one of the reasons leading to the smaller sizes of wax crystals. The XRD result also showed that with higher asphaltene content, the lattice parameter c of wax crystals obviously increases, indicating that the conformation of wax crystals gets more disordered, which results in the weakening of gel strength, corresponding to the decline of the measured yield stress of the waxy oil gel. With higher asphaltene content, the zeta potential of wax crystals goes up, which indicates that with more negative charges adsorbed on the wax crystal surfaces, stronger electrostatic double layers have formed. The greater electrostatic repulsion among wax crystals would interfere with the growth and aggregation of wax crystals, thus holding up the gelation of waxy oils.
研究领域:
石油工程
·
材料科学
✓ 已验证
DOI
高影响因子
Petroleum Science
·
2024
·
IF 6
Xin-Yuan Li,Xu-Biao Zhang,Si-Bei Li,Li-Wei Hui,Xin-Jie Sun,Jun Xu
The gelation of crude oil with high wax and asphaltene content at low temperatures often results in the block of transportation pipeline in Africa. In recent years, it was reported that surface hydrophobic-modified nanoparticles have important applications in crude oil flow modification. In this work, four kinds of core-shell hybride nanoparticles by grafting poly (octadecyl, docosyl acrylate) and poly (acrylate-α-olefin) onto the surface of nano-sized SiO 2 were synthesized by grafting polymerization method. The chemical structure of nanoparticles was analyzed by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). The rheological behaviors of crude oil and precipitation of asphaltenes in the presence of nanoparticles were studied by measuring the viscose-temperature relationship curve, the cumulative wax precipitation amount, and morphology of waxes and asphaltenes. The results indicate that the docosyl polyacrylate@SiO 2 nanoparticle (PDA@SiO 2 ) can reduce the cumulative wax precipitation amount of crude oil by 72.8%, decline the viscosity of crude oil by 85.6% at 20 °C, reduce the average size of wax crystals by 89.7%, and inhibit the agglomeration of asphaltene by 74.8%. Therefore, the nanoparticles not only adjust the crystalline behaviors of waxes, but also inhibit the agglomeration of asphaltenes. Apparently, core-shell hybride nanoparticles provides more heterogeneous nucleation sites for the crystallization of wax molecules, thus inhibiting the formation of three-dimensional network structure. The core-shell polymer@SiO 2 hybride nanoparticles are one of promising additives for inhibiting crystallization of waxes and agglomeration of asphaltenes in crude oil.
研究领域:
材料科学
·
石油工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Energy Storage
·
2024
·
IF 8.9
Yi Wang,Xiaofeng Yuan,Jianjun Wang,Jianrong Wang,Ting Zhang,Yi Zheng,Yangtao Xu
The introduction of porous matrix in shape stable phase change materials (PCMs) alters the phase transition behavior of confined molecules. The mechanism by which the matrix affects the thermophysical properties of composite PCMs is still unclear, even there are conflicting understandings of the same phenomenon. According to this, paraffin/Kevlar nanofibrous films (PF/KNF) with different PF contents were fabricated by one step self-assembly method to comprehensively evaluate the regulation of confinement effects on the thermophysical properties and crystallization kinetics of confined PCMs. Due to the strong self-assembly tendency of Kevlar nanofibers in proton environment, paraffin passively wrapped in the network of matrix, forming a sandwich layered structure. The confinement of matrix altered the crystal structure of paraffin, even leading to the amorphous states in films with lower paraffin content. It also leaded to the formation of a non-melting layer at host-guest interface, thereby reducing the latent heat of composite PCMs. The latent heat of PF/KNF-70, the film with the highest paraffin content without leakage, decreased by about 32.7 % compared to the theoretical enthalpy calculated based on the mass percentage of paraffin in composite. In addition, the percentage of non-phase transition layer decreased linearly with the increase of PF content. The results of crystalline dynamics indicate that the matrix plays a dual role in providing nucleation sites and inhibiting molecular motion. When crystallization occurs at higher temperature (48.8 °C in this study), providing nucleation sites and promoting crystallization dominated the process, while inhibiting molecular motion and reducing crystallization rate become more prominent when crystallization temperature decreases.
研究领域:
材料科学
·
热能工程
✓ 已验证
产品关联
DOI
高影响因子
ENERGY & FUELS
·
2024
·
IF 5.2
Shi-dong Zhou,Zhen-hao Ren,Yi-song Yu,Yang Liu,Xiao-fang Lv,Hui Du
During the operation of deep-sea pipelines, the accumulation and deposition of hydrates are important reasons for pipeline blockage. The current main measure to solve the hydrate plugging problem is the addition of low-dose inhibitors (LDHIs), but it is not yet known whether the precipitation of wax crystals will affect their effectiveness. Therefore, in this study, the hydrate cohesive force within the wax-free/wax-containing system was directly measured by using a micromechanical force device (MMF) and the reasons for the change in cohesive force were analyzed from a morphological point of view. The results showed that glycine was effective in reducing the cohesion between hydrate particles in both wax-free/wax-containing systems and still exerted the effect of antiagglomeration agent (AA) at very low concentrations (as low as 0.10 wt %). Moreover, the optimum concentration of glycine was 0.50 wt %. At this concentration, the cohesive force decreased from 8.54 to 7.07 mN/m in the wax-free system, a decrease of about 17.2%, while the cohesive force decreased from 5.94 to 2.15 mN/m in the wax-containing system, a decrease of about 63.8%. By observation of the morphology of the hydrate particles, the presence of glycine was found to reduce the volume of the liquid bridge by changing the surface roughness and wettability of the particles, thereby reducing the cohesive force. And when wax was contained in the system, the wax further reduced the wettability by adsorbing on the surface of the hydrate particles. However, under certain AA conditions, the increase in wax concentration (from 0.1 to 0.3 wt %) resulted in the free water inside the hydrate being more likely to form liquid bridges with the surrounding particles, thus weakening the effect of AA. This work analyzes the effect on cohesive force in the simultaneous presence of LDHIs and wax from a morphological point of view, which is beneficial in providing more insights into securing safe hydrate flow management.
研究领域:
石油工程
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
POLYMER COMPOSITES
·
2026
·
IF 4.9
Menghan Li,Xiong Ma,Ting Wang,Jiaxin Tang,Haixin Bi,Tianhao Zhang,Yuexin Hu,Miao Xie,Shanshan Zhao
Carbon fiber reinforced polyethylene (CF/PE) composites are widely used in aerospace, automotive, and sports equipment applications. The interphase acts as the critical bridge for stress transfer. However, the carbon fiber surface is nonpolar and smooth and lacks reactive functional groups, while the polyethylene molecular chains also contain no reactive groups. This leads to weak interfacial bonding between the fibers and the matrix. A weak interface easily undergoes debonding, leading to internal crack formation and severely limiting the overall mechanical performance of the composites. Herein, a polyethylene wax (PEW)-derived sizing agent functionalized with maleic anhydride (MAH) was applied onto carbon fiber surfaces via aqueous coating to construct an interfacial transition layer, thereby enhancing the interfacial adhesion in CF/PE composites. Successful sizing was verified by x-ray photoelectron spectroscopy (XPS). The tensile and impact strengths of the modified CF/PE composites were enhanced by 73.2% and 20.0%, respectively; the interfacial shear strength (IFSS) improved from 5.43 to 18.45 MPa; and the interlaminar shear strength (ILSS) increased from 53.47 MPa for untreated CF/PE composites to 63.27 MPa. The results indicate that the compatibilizer, based on similar compatibility and esterification effects, improved the interfacial adhesion of the composites. Highlights Reactive PE wax sizing agent with maleic anhydride groups was prepared. Robust interfacial adhesion between CF and PE via chemical surface modification. Poor compatibility between conventional epoxy sizes and polyolefins was overcome.
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2025
·
IF 6.9
Xuanyan Liu,Shuo Wang,Jiaxing Wang,Hongdi Fu,Kangcheng Xu,Xiaodong Li,Tinglu Song,Meishuai Zou
Aluminum-lithium alloys (Al-Li alloys) have gained prominence in recent years as promising alternatives to aluminum powders, attributed to their superior thermal and combustion characteristics. However, the high reactivity of Al-Li alloys poses significant challenges to their stability and compatibility with other materials. This study utilized high-energy ball milling to modify Al-Li alloys by incorporating polytetrafluoroethylene (PTFE) and paraffin wax (WAX) as functional coatings. Thermal analysis of Al-Li/PTFE composites revealed a marked reduction in the thermal oxidative exothermic peak temperature with the addition of 10 % and 15 % PTFE, accompanied by enthalpy increases of 1.49 and 2.1 times, respectively. Combustion processes captured using a high-speed camera demonstrated that increasing the PTFE content from 10 % to 30 % intensified the combustion and reduced combustion duration by 50 %. The agglomeration of combustion residues also decreased. Furthermore, incorporating WAX through ball milling facilitated high-temperature phase transformations, producing Al-Li/10PTFE/2WAX composite powders with enhanced antioxidant properties, as evidenced by a contact angle of 131.15°, and improved compatibility. The findings offer a pathway for achieving tunable combustion performance in Al-Li alloys while addressing critical issues related to the storage and processing of these powders for practical applications.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2025
·
IF 2.8
Hao Zhang,Shengtai Zhou,Liwei Yan,Mei Liang,Huawei Zou
This study relies on the high ablation resistance strategy of char layer expansion ceramization to strengthen the char layer and improve ablation performance. The use of phase change material, that is, paraffin wax, was effective in simultaneously improving the ablation resistance and thermal insulation performance of liquid methyl vinyl silicone rubber (LMVSR) composites, which was attributed to the low density, enhanced char layer, and improved heat-absorption capacity. The introduction of paraffin wax lowered the ablation temperature and increased the specific heat capacity of LVMSR-based composites, thereby enhancing heat dissipation and reducing thermal erosion. In addition, paraffin wax was able to promote the ceramization reaction. The mass erosion rate, pyrolysis rate, and graphitization degree of the char layer were significantly improved when the content of paraffin wax was increased from 5 to 15 phr. The composites with 15 phr paraffin wax demonstrated the best performance and the highest modification effect. The paraffin modification was effective in reducing the mass ablation rate, especially at 10 phr, which showed a decrease of 34.43% when compared with that of the L-P0 counterpart. The maximum back-face temperature was reduced by 29.63% upon adding 15 phr paraffin wax when compared with L-P0, exhibiting excellent thermal insulation performance. The above results showed that the ablative resistance, internal erosion resistance, and thermal insulation properties of silicone rubber-based composites were significantly improved by using the strategy of expansion ceramization and enhanced heat absorption/dissipation by adding phase change materials, which shows potential application in preparing flexible thermal ablative material for thermal protection purposes.
研究领域:
材料科学
·
聚合物复合材料
·
热防护系统
·
烧蚀材料
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS CHEMISTRY AND PHYSICS
·
2026
·
IF 4.7
Zhiwei Liu,Hang Qin,Jiawei Xie,Wenming Guo,Pengzhao Gao,Hanning Xiao,Jingxiong Liu,Yang Li,Weiqun Zhang,Mouyun Yuan
This study presents a malic-acid-mediated chelation strategy for preparing high-solid-content, aggregation-resistant yttrium sols tailored for titanium–aluminide investment casting. By systematically tuning the molar ratios of YCl 3 , Y(OH) 3 , and malic acid, the coordination structure and colloidal stability were clarified. Under optimal conditions (YCl 3 :Y(OH) 3 = 10:2; Y(OH) 3 :malic acid = 1:2), malic acid coordinated with yttrium through combined monodentate and bidentate modes, forming stable five- and six-membered chelate rings that effectively suppressed hydrolysis. The optimized sol achieved a solid content of 26.70 % with a zeta potential of 27 mV. In contrast, acetic, oxalic, and acrylic acids predominantly formed monodentate complexes, resulting in inferior stability. A critical solid-content threshold was identified, beyond which rapid gelation occurred. To enhance sol uniformity and mitigate the adverse effects of residual chloride ions during shell fabrication, the sol was dialyzed for 30 min in a pH 3.5 malic acid solution. After dialysis, the sol retained a solid content above 24 %, exhibited a zeta potential of 27.3 mV, and showed uniformly distributed spherical particles with an average size of 75 nm, confirming excellent stability and suitability for investment casting applications.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2016
·Vol. 51
·期 18
·8550-8561
·
IF 2.302
Sun Na,Xiao Zhenggang
Solid paraffin was encapsulated by water-dispersible Si 3 N 4 nanoparticles (nano-Si 3 N 4 ) functionalized with amphiphilic polymer chains using an eco-friendly Pickering emulsion route to prepare a sort of composite phase change materials (PCMs) for thermal energy storage. In this method, the oil phase of melted paraffin and monomers could be easily encapsulated and stabilized by the nano-Si 3 N 4 Pickering stabilizer in an aqueous medium. The subsequent polymerization reaction and polymer-induced phase separation of the oil cores allowed for the formation of the phase change composite microcapsules embedded with nano-Si 3 N 4 in the polymer shell. The chemical structure and morphology of the composite PCMs were characterized by Fourier transform infrared spectroscopy and scanning electron microscope, respectively. Results showed that the composite PCMs with a well-defined spherical structure are prepared successfully. In addition, differential scanning calorimeter, thermogravimetric analysis, and thermal conductivity measurement were applied to measure the thermal storage capacity and thermal properties of these microcapsules. These results showed that the microcapsule can achieve the best performances, including high encapsulation efficiency and desirable morphology, with the nano-Si 3 N 4 percentage up to 10 wt% (paraffin mass). Moreover, the thermal conductivity of the prepared PCM microcapsules was significantly enhanced owing to the presence of the nano-Si 3 N 4 . The prepared PCM microcapsules are expected to apply in energy storage field.
研究领域:
材料科学
·
热能存储
·
纳米复合材料
·
聚合物化学
✓ 已验证
DOI
高影响因子
Cell Reports
·
2026
·Vol. 45
·期 3
·
IF 7.7
Haipo Yang,Lin Meng,Yue La,Xuanhao Zhang,Tiancan He,Xinyi Huo,Hui Song,Minghui Tan,Simin Wu,Lin Xiang,Shiyou Lü,Zhulong Chan,Yanping Wang
Flower aging, or senescence, is generally accompanied by petal dehydration/wilting. The cuticle functions as a barrier to withhold water for plant organs. However, little is known about how the cuticle modifies the process of petal development. Here, we report that cuticular wax is dynamically changed during petal senescence and wax coverage on petals is coordinated with the expression of TgWIN1 . Functional identification indicates that TgWIN1 positively regulates wax accumulation and delays petal senescence. TgNAC2 promotes petal senescence by inhibiting TgWIN1 expression in senescent petals, while TgFbox1 degrades TgNAC2 protein accumulation via ubiquitination. Additionally, both abscisic acid (ABA) and ethylene contribute to petal senescence by promoting TgNAC2 expression but inhibiting TgFbox1 expression, respectively. Thus, we propose an ABA/ethylene-mediated TgFbox1-TgNAC2-TgWIN1 module that precisely regulates the cuticular wax biosynthesis and petal senescence, offering potential targets for optimizing flower longevity and wax biosynthesis in plants.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）