COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING
·
2018
·
IF 4.514
Yuxin He,Qiuyu Chen,Song Yang,Chang Lu,Mengting Feng,Yuanli Jiang,Guoxi Cao,Jianping Zhang,Chuntai Liu
The epoxy nanocomposites with Fe 3 O 4 modified graphene oxide (Fe 3 O 4 /GO) were used to influence the micro-cracks resistance of carbon fiber reinforced epoxy (CF/EP) laminate at 77 K. Fe 3 O 4 /GO with good paramagnetic properties were prepared by co-precipitation method and used to modify epoxy for cryogenic applications. Fe 3 O 4 /GO modified CF/EP laminates were also prepared through vacuum-assisted resin transfer molding (VARTM). The results show that the Fe 3 O 4 /GO can effectively improve the mechanical properties of epoxy (EP) matrix at 77 K and reduce the coefficient of thermal expansion (CTE) of EP matrix. It also can obviously improve the micro-cracks resistance of CF/EP composites at 77 K. Compared to neat EP, the CTE of Fe 3 O 4 /GO modified EP composite is decreased 51.6%. Compared to CF/EP composite, the micro-cracks density of Fe 3 O 4 /GO modified CF/EP composite at 77 K is decreased 60.0%.
研究领域:
材料科学
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高分子复合材料
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低温工程
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纳米复合材料
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力学性能
✓ 已验证
DOI
高影响因子
PROPELLANTS EXPLOSIVES PYROTECHNICS
·
2024
·Vol. 50
·期 3
·e202400232
·
IF 1.7
Bo Hao,Caixian Xu,Geng Chen,Yuangen Lu,Li Zhang
In response to issues such as poor accuracy and unstable delay times encountered in the practical use of tungsten-based delay compositions, an analysis of the combustion performance of tungsten-based delay compositions with the addition of copper oxide was conducted. This study selected five tungsten-based composite delay compositions prepared by blending tungsten-based delay compositions with copper oxide at different content, aiming to investigate the influence of varying copper oxide proportions on the combustion characteristics of tungsten-based delay compositions. Microscopic morphologies and thermal decomposition behaviors of the tungsten/copper oxide delay compositions were analyzed using scanning electron microscopy (SEM) and differential scanning calorimetry (DSC), while combustion products were examined by X-ray diffraction (XRD). The results indicate that copper oxide exerts a strong catalytic decomposition effect on tungsten-based delay compositions. Specifically, a low concentration of copper oxide enhances the combustion rate of tungsten-based delay compositions, while an increase in copper oxide content subsequently slows down the combustion rate. Notably, tungsten-based delay compositions with 9% copper oxide content demonstrate high precision, good stability, and a relatively slow combustion rate, offering a wider range of adjustability for controlling the combustion speed of delay compositions and providing a feasible method for managing the delay time range in practical applications.
研究领域:
材料科学
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火工品技术
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燃烧学
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无机化学
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功能材料
✓ 已验证
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2024
·
IF 4.9
Zhenghua Sun,Yahui Ji,Haicheng Wang,Jingyi Zhang,Cheng Yuan,Mingjie Kang,Yujun Feng,Hongyao Yin
The incorporation of hydroxy groups into long-chain quaternary ammonium surfactants can enhance their solubility and confer other desirable properties; however, the systematic investigation on the solution properties and the influence of molecular structures was less documented. In this work, two saturated C 18 -tailed quaternary ammonium surfactants with dual hydroxyethyl moieties, namely N , N -bis(2-hydroxyethyl)- N -methyloctadecan-1-aminium iodide (HEOAI) and N , N -bis(2-hydroxypropyl)- N -methyloctadecan-1-aminium iodide (HPOAI), were designed and synthesized. We investigated and compared their Krafft temperature ( T k ), surface activities, self-assembly behaviors, and rheological properties. Our findings demonstrate that the introduction of hydroxyethyl groups dramatically improves the solubility and surface activities. The T k of HEOAI and HPOAI is approximately 50 °C lower than that of the corresponding surfactant octadecyl trimethylammonium iodide. Both surfactants exhibit lower critical micelle concentration and equilibrium surface tension compared to those of corresponding conventional quaternary ammonium surfactant. This should be ascribed to the formation of hydrogen bonds between hydroxyl groups and water molecules. Moreover, HPOAI shows even better solubility and surface activities than HEOAI does. Additionally, the presence of two more methyl groups for HPOAI enhances its ability to form worm-like micelles in pure water. However, HEOAI shows better salt and temperature resistance for maintaining stability of worm-like micelles. A solution containing 50 mM HEOAI with 10 % NaCl exhibits temperature tolerance up to around 80 °C, indicating potential application as fracturing fluid for shallow and medium oil/gas reservoirs. These findings contribute to designing surfactants with improved solubility and diverse properties.
研究领域:
物理化学
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胶体与界面科学
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材料化学
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石油工程
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表面活性剂化学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING RESEARCH & DESIGN
·
2024
·
IF 3.7
Xiaofei Xu,Xiaolong Li,Zhi Li,Da Zhang
An experimental study of single carbon dioxide (CO 2 ) bubbles ascending in aqueous solutions of carboxymethyl cellulose (CMC) is performed as a means to obtain further understanding of the rising behavior and mass transfer of soluble bubbles in shear-thinning non-Newtonian fluids. High-speed photography and digital image processing technique are employed to quantify the characteristic parameters of the bubble rising process. The rising behavior of single CO 2 bubbles in a Newtonian fluid (tap water) is measured as a reference. It has been found that the rheology of the liquid phase significantly influenced the rising behavior of the bubbles. In CMC aqueous solutions, CO 2 bubbles mostly followed a straight rising path characterized by increasing aspect ratio and decreasing vertical velocity. Increase in initial bubble size led to bubble deformation in less concentrated CMC aqueous solutions which resulted in an irregular rising path. The evolution of bubble equivalent diameter can be mainly divided into two stages: a fast reduction stage followed by a slow one. Meanwhile, the variation of liquid-side mass transfer coefficient k L of CO 2 bubbles in tap water and CMC aqueous solution with different weight percentages is discussed. The mobility of gas-liquid interface is considered to have significant impact on gas-liquid mass transfer. A dimensionless correlation considering the rheology of the liquid phase is proposed to describe the evolution of the motion and deformation of single soluble CO 2 bubbles in infinite stagnant shear-thinning non-Newtonian liquids.
研究领域:
流体力学
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化学工程
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多相流
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传质过程
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非牛顿流体动力学
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气泡动力学
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环境工程
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF PHARMACEUTICS
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2013
·
IF 3.458
Ziwei Zhang,Xiaole Qi,Xiangbo Li,Jiayu Xing,Xuehua Zhu,Zhenghong Wu
Multilayer-coating technology is the traditional method to achieve pulsatile drug release with the drawbacks of time consuming, more materials demanding and lack of efficiency. The purpose of this study was to design a novel pulsatile drug delivery system based on the physiochemical interaction between acrylic copolymer and organic acid with relatively simpler formulation and manufacturing process. The Enalapril Maleate (EM) pulsatile release pellets were prepared using extruding granulation, spheronization and fluid-bed coating technology. The ion-exchange experiment, hydration study and determination of glass transition temperature were conducted to explore the related drug release mechanism. Bioavailability experiment was carried out by administering the pulsatile release pellets to rats compared with marketed rapid release tablets Yisu ® . An obvious 4 h lag time period and rapid drug release was observed from in vitro dissolution profiles. The release mechanism was a combination of both disassociated and undisassociated forms of succinic acid physiochemically interacting with Eudragit ® RS. The AUC0-τ of the EM pulsatile pellets and the market tablets was 702.384 ± 96.891 h ng/mL and 810.817 ± 67.712 h ng/mL, while the relative bioavailability was 86.62%. These studies demonstrate this novel pulsatile release concept may be a promising strategy for oral pulsatile delivery system.
研究领域:
药剂学
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药物递送
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生物药剂学
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药物代谢
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制剂工程
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药动学
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2017
·
IF 3.387
Yan Zhao,Yang Gao
The microstructure of plasma-sprayed nanostructured yttria-stabilized zirconia (YSZ) coatings may change during high-temperature exposure, which would influence the coating performance and service lifetime. In this study, the phase structure and the microstructural evolution of 3YSZ (zirconia-3 mol% yttria) and 5YSZ (zirconia-5 mol% yttria) nanostructured coatings were investigated by means of sintering at 1400 °C for 50–100 h. The microhardness, elastic moduli, and thermal shock cycles of the 3YSZ and 5YSZ nanostructured coatings were also investigated. The results showed that the redistribution of yttrium ions at 1400 °C caused the continuous increase of monoclinic-phase zirconia, but no obvious inter-splat cracking formed at the cross-sections, even after 100 h. Large voids appeared around the nanoporous zone because of the sintering of nanoscale granules upon high-temperature exposure. The microhardness and elastic moduli of the nanostructured coatings first increased and then decreased with increasing sintering times. The growth rate of the nanograins in the 3YSZ coating was lower than that in 5YSZ, which slowed the changes in 3YSZ coating porosity during sintering. Although the 3YSZ coating was prone to monoclinic phase transition, the experimental results showed that the thermal shock resistance of the 3YSZ coating was better than that of the 5YSZ coating.
研究领域:
材料科学
·
表面工程
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陶瓷涂层
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热障涂层
·
高温材料
✓ 已验证
DOI
高影响因子
Advanced Energy Materials
·
2016
·Vol. 7
·期 8
·1602149
·
IF 15.23
Shanshan Yao,Jiang Cui,Ziheng Lu,Zheng-Long Xu,Lei Qin,Jiaqiang Huang,Zoya Sadighi,Francesco Ciucci,Jang-Kyo Kim
Carbon-coated van der Waals stacked Sb 2 S 3 nanorods (SSNR/C) are synthesized by facile hydrothermal growth as anodes for sodium ion batteries (SIBs). The sodiation kinetics and phase evolution behavior of the SSNR/C anode during the first and subsequent cycles are unraveled by coupling in situ transmission electron microscopy analysis with first-principles calculations. During the first sodiation process, Na + ions intercalate into the Sb 2 S 3 crystals with an ultrafast speed of 146 nm s −1 . The resulting amorphous Na x Sb 2 S 3 intermediate phases undergo sequential conversion and alloying reactions to form crystalline Na 2 S, Na 3 Sb, and minor metallic Sb. Upon desodiation, Na + ions extract from the nanocrystalline phases to leave behind the fully desodiated Sb 2 S 3 in an amorphous state. Such unique phase evolution behavior gives rise to superb electrochemical performance and leads to an unexpectedly small volume expansion of ≈54%. The first-principles calculations reveal distinctive phase evolution arising from the synergy between the extremely low Na + ion diffusion barrier of 190 meV and the sharply increased electronic conductivity upon the formation of amorphous Na x Sb 2 S 3 intermediate phases. These findings highlight an anomalous Na + ion storage mechanism and shed new light on the development of high performance SIB anodes based on van der Waals crystals.
研究领域:
材料科学
·
电化学
·
纳米科技
·
能源存储
·
固态物理
·
计算材料学
✓ 已验证
DOI
高影响因子
Acta Biomaterialia
·
2021
·
IF 8.947
Xian Tong,Wenhao Cai,Jixing Lin,Kun Wang,Lufan Jin,Zimu Shi,Dechuang Zhang,Jianguo Lin,Yuncang Li,Matthew Dargusch,Cuie Wen
Zinc (Zn)-based alloys have been considered potential biodegradable materials for medical applications due to their good biodegradability and biocompatibility. However, the insufficient mechanical properties of pure Zn do not meet the requirements of biodegradable implants. In this study, we have developed a biodegradable Zn−3Mg−0.7Mg 2 Si composite fabricated by high-pressure solidification. Microstructural characterization revealed that the high-pressure solidified (HPS) composite exhibited uniformly distributed fine MgZn 2 granules in an α-Zn matrix. Comprehensive tests indicated that the HPS composite exhibited exceptionally high compression properties including a compressive yield strength of 406.2 MPa, an ultimate compressive strength of 1181.2 MPa, and plastic deformation up to 60% strain without cracking or fracturing. Potentiodynamic polarization tests revealed that the HPS composite showed a corrosion potential of −0.930 V, a corrosion current density of 3.5 μA/cm 2 , and a corrosion rate of 46.2 μm/y. Immersion tests revealed that the degradation rate of the HPS composite after immersion in Hanks’ solution for 1 month and 3 months was 42.8 μm/y and 37.8 μm/y, respectively. Furthermore, an extract of the HPS composite exhibited good cytocompatibility compared with as-cast (AC) pure Zn and an AC composite at a concentration of ≤25%. These results suggest that the HPS Zn−3Mg−0.7Mg 2 Si composite can be anticipated as a promising biodegradable material for orthopedic applications .
研究领域:
生物医学工程
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材料科学
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生物材料
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骨科
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可降解金属
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组织工程
·
腐蚀科学
✓ 已验证
DOI
高影响因子
JOURNAL OF ENZYME INHIBITION AND MEDICINAL CHEMISTRY
·
2019
·
IF 4.027
Yu-Heng Hu,Jie Yang,Yun Zhang,Ke-Chun Liu,Teng Liu,Jie Sun,Xiao-Jing Wang
The work is focused on the design of drugs that prevent and treat Alzheimer’s disease (AD) and its complications. A series of 3–(4-aminophenyl)-coumarin derivatives designed, synthesised, fully characterised and evaluated in vitro/vivo. The biological assay experiments showed that some compounds displayed a clearly selective inhibition for acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). Among all compounds, compound 4m exhibited the highest AChE inhibition with an IC50 value of 0.091 ± 0.011 µM and compound 4k exhibited the highest BuChE inhibition with an IC50 value of 0.559 ± 0.017 µM. A zebrafish behaviour analyser (Zebrobox) was used to determine the behavioural effects of the active compound on the movement distance of the aluminium chloride-induced zebrafish. Compound 4m offered a potential drug design concept for the development of therapeutic or preventive agents for AD and its complications.
研究领域:
药理学
·
神经科学
·
药物设计
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF CLUSTER SCIENCE
·
2017
·Vol. 28
·期 6
·3059-3066
·
IF 1.471
Liang Hua,Yang Zhen-Yuan,Yan Min-Hao,Xie Su-Yuan
The fullerenes that violate isolated pentagon rule (IPR) have unusual electronic properties resulting from their fused-pentagon structures. Numerous non-IPR fullerenes have now been captured by chlorination, affording opportunity to go insight into the properties involved in non-IPR fullerenes in the forms of chlorofullerenes (CFs). Here cyclic voltammetry (CV) is employed to probe the electrochemical properties of non-IPR #1809 C 60 Cl 8 in comparison with those of #271 C 50 Cl 10 . Differing from IPR-satisfying CFs such as C 60 Cl 8 and C 60 Cl 10 (referring to I
h -symmetric C 60 ), the two non-IPR CFs exhibit divergent electroactive polymerization characters. In addition, the electrocatalytic effect of ferrocene that is otherwise employed as internal reference has been shown in the CV process of CFs.
研究领域:
材料化学
·
物理化学
·
纳米材料
·
电化学
·
富勒烯化学
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2018
·
IF 5.091
Siyuan Dong,Yingqi Jia,Xiaozhi Xu,Jianeng Luo,Jingbin Han,Xiaoli Sun
Poly(ethylene terephthalate) (PET) generally suffers from low crystallization rate and long molding duration, which as a result limit its application as engineering plastics. To overcome these drawbacks, series of PET/layered double hydroxide (LDH) nanocomposites were prepared by a solution blending process. The effect of metal composition (MgAl and CaAl) and organo-modification (stearic acid intercalated) for LDH fillers on the crystallization behavior of the nanocomposites was investigated. It was revealed that, compared with PET/CaAl-LDH, the PET/MgAl-LDH nanocomposite exhibits a higher crystallization temperature and faster crystallization rate, which is associated with the superior nucleation ability of MgAl-LDH. The nucleation mechanism of PET induced by LDHs was explored by means of Avrami equation and theory of Hoffman-Lauritzen, pointing out that the incorporation of LDHs reduce the free energy of nucleation and the fold surface free energy of PET. In order to improve the compatibility between LDH and PET, stearic acid (SA) intercalated MgAl-LDH was prepared and filled into PET matrix. The resultant PET/MgAl-LDH-SA shows a further enhanced crystallization temperature and accelerated crystallization rate, in comparison with PET/MgAl-LDH nanocomposites. In addition, the thermal stability, gas barrier and mechanical properties of PET/LDH composites were improved upon incorporation of LDH fillers.
研究领域:
高分子科学
·
材料化学
·
纳米复合材料
·
结晶动力学
·
聚合物物理
·
功能材料
·
工程塑料
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）