COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2024
·
IF 4.9
Peng Bao,Su Jiang,Yang Chen,Yuanlin Fan,Yaning Li,Boliang Wang
Despite the extensive researches on CL-20 crystals, the mechanical safety issues and process problems of CL-20 applications have not been studied in-depth. Herein, the cellulose nanocrystals (CNC) was doped in microcrystalline wax (MW), oxidized microcrystalline wax (OMW) and hydrogel (PPC) to design and fabricate the cross-linked CL-20 composites by simple water-suspension melting and freeze-drying methods. The composites were characterized by SEM, XPS, TG-DSC, XRD, mechanical sensitivity device and inclined chute tester. It is found that the CNC@OMW composite film exhibits excellent coating effect (99.96%) on CL-20 due to the cross-linking results. The E a of CL-20 is increased from 190.92 to 388.71 kJ/mol under the synergistic effect of the excellent compatibility between components and the compact coating structure of CNC@OMW. Additionally, the film enhances the T p0 of CL-20 from 218.15 to 222.66 ℃ and T b from 220.27 to 223.73 ℃, respectively. While, the PPC@CNC only promoted E a , T p0 and T b of CL-20–292.89.71 kJ/mol, 224.22 ℃ and 225.66 ℃, respectively. Besides, the XRD results confirms that three composite films dose not cause a transformation of the ε- CL-20 crystal phase. Most importantly, the cross-linked film brings mechanical sensitivity of CL-20 from 60 N and 3.5 J to a level of over 360 N and 10.4 J, comparable to WO 3 /Al nanothermite with 5 wt% polyaniline (360 N) and composite with 95 wt% LLM-105 and 5 wt% ternary (11–12 J). This improvement enables the composite explosives to be handled using standard procedures. Furthermore, the ability of the particles to accumulate electrostatic charge after cross-linking coating is significantly reduced, and PVC is more suitable as the contact material of CL-20 and composite particles than copper for use in the transportation and packaging. These findings can serve as a reference for wide application of CL-20.
研究领域:
材料科学
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炸药工程
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ELECTRONIC MATERIALS
·
2025
·
IF 2.5
Wang Fangyu,Wen Yijie,Guo Xin,Zhang Xuanhao,Hu Shuai,Yuan Maohui,Han Kai
Upconversion nanomaterials have been extensively applied in many fields owing to their unique optical and electronic properties. In this work, β-NaYF 4 :Yb 3+ /Ho 3+ microcrystals were synthesized by an improved hydrothermal method. The morphology and the composition of the prepared microcrystals were experimentally investigated in detail by scanning electron microscopy (SEM) and X-ray diffraction (XRD). Under the excitation of a 980 nm continuous-wave (CW) laser, the green (541 nm) and red (644 nm) upconversion luminescence (UCL) of Ho 3+ through the energy transfer upconversion processes assisted by the Yb 3+ ions were experimentally studied at the single-particle level. With the gradual increase of excitation intensity in the highly doped Yb 3+ microcrystals, the red UCL was enhanced significantly more than the green UCL and was dominant, resulting in the UCL color finally tuning to pure red. Comparatively, for the lightly doped Yb 3+ microcrystals, the green UCL exhibited a relatively similar increase to the red UCL. The populations of the Yb 3+ and Ho 3+ ions and transitions of the UCL were systematically demonstrated through calculation of the energy levels. Notably, a new UCL at 580 nm was observed, which was ascribed to the transition of 5 F 1 , 5 G 6 → 5 I 7 .
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
Minerals
·
2019
·Vol. 10
·期 1
·24
·
IF 2.25
Pengfei Hu,Long Liang,Yaoli Peng,Hesheng Yu,Guangyuan Xie
Efficient beneficiation of microcrystalline graphite remains a challenge. Selective recovery of microcrystalline graphite from quartz using hydrophobized magnetite as magnetic seed is studied in this work. Magnetite was hydrophobized by the surface coating of sodium oleate. The hydrophobic agglomerates were then separated by magnetic separation. Sedimentation experiments were performed to study the adhesion of microcrystalline graphite and quartz to magnetite particles. The results showed that hydrophobized magnetite led to a higher microcrystalline graphite recovery than that of the original magnetite, due to the higher probability to bond with microcrystalline graphite. However, the hydrophobization of the magnetite surface had an insignificant effect on its interaction with quartz. The force analysis based on the extended Derjaguin-Landau-Verwey-Overbeek (EDLVO) theory indicated that the total attractive interaction between hydrophobized magnetite and microcrystalline graphite were obviously stronger than that between hydrophobized magnetite and quartz, resulting in the selective aggregation between hydrophobized magnetite and microcrystalline graphite.Keywords:microcrystalline graphite;hydrophobized magnetite;magnetic seeding;aggregation
研究领域:
矿物加工工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Polymers
·
2022
·Vol. 14
·期 9
·1786
·
IF 4.967
Dongyang Liu,Yuqing Duan,Shumei Wang,Murong Gong,Hongqi Dai
Studies have shown that fluorinated oil repellents are potentially harmful to humans and the environment, and therefore, the development of non-toxic, green, and environmentally friendly oil repellents has become inevitable. Microcrystalline wax is a branched saturated alkane with a molecular weight of 580–700 Da, which has a lower surface tension than edible oil. Herein, microcrystalline wax emulsion (fluorine-free oil repellent) was prepared by mechanical stirring–homogenization, the effects of emulsifier ratio and dosage on the emulsion performance were systematically investigated, and the resultant stable microcrystalline wax emulsions were applied to the paper surface to explore the oil and water resistance and water vapor barrier performance. The results showed that stabilized microcrystalline wax emulsion was obtained at the emulsifier Span-80/Tween-80 ratio of 5:5, and the emulsifier dosage was 20% (relative to the microcrystalline wax). When 6 g/m2of microcrystalline wax was applied to the surface of starch pretreated paper, the kit rating value of the paper was high, at up to 10/12, the Cobb60value decreased to 12.5 g/m2, the overall migration of paper was less than 10 mg/dm2, and the water vapor permeability was reduced by 81.9%, which met the requirements of oil and water resistance performance of food packaging paper.Keywords:microcrystalline wax emulsion;oil and water resistance;fluorine-free oil repellent
研究领域:
食品科学
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材料科学
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环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Soft Matter
·
2017
·Vol. 13
·期 45
·8636-8643
·
IF 3.889
Ce Wang,Xulong Cao,Yangwen Zhu,Zhicheng Xu,Qingtao Gong,Lei Zhang,Lu Zhang,Sui Zhao
The transformation of cyclodextrins (CDs) and alkanes from separated monomers to inclusion complexes at the interface is illustrated by analyzing the evolution of interfacial tension along with the variation of interfacial area for an oscillating drop. Amphiphilic intermediates are formed by threading one CD molecule on one alkane molecule at the oil/aqueous interface. After that, the amphiphilic intermediates transform into non-amphiphilic supramolecules which further assemble through hydrogen bonding at the oil/aqueous interface to generate a rigid network. With the accumulation of supramolecules at the interface, microcrystals are formed at the interface. The supramolecules of dodecane@2α-CD grow into microrods which form an unconsolidated shell and gradually cover the drop. However, the microcrystals of dodecane@2β-CD are significantly smaller which fabricate into skin-like films at the interface. The amphiphilic intermediates during the transformation increase the feasibility of self-emulsification and the skin-like films enhance the stability of the emulsion. With these unique properties, CDs can be promising for application in hydrophobic drug delivery, food industry and enhanced oil recovery.
研究领域:
材料科学
·
药物传递系统
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食品科学
·
石油工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2023
·Vol. 34
·期 36
·1-12
·
IF 2.8
Yang Huiyuan,Guo Rongshuo,Jin Linghua,Zhang Ye,Wang Weike
The design and fabrication of transition metal sulfides for supercapacitors have attracted considerable attention in recent years because of their potential for energy storage applications. Conventionally, the synthesis process involved subjecting them to high temperatures and pressures, which can be energy-intensive and environmentally unfriendly. Herein, microcrystalline NiCo 2 S 4 nanorods were prepared under ambient temperature and pressure using a two-step method. The Ni 1/3 Co 2/3 C 2 O 4 nanorods were initially synthesized using the coprecipitation technique, and then the NiCo 2 S 4 nanorods were obtained by sulfurating Ni 1/3 Co 2/3 C 2 O 4 with Na 2 S·9H 2 O under ambient conditions. The NiCo 2 S 4 as a high-performance supercapacitor electrode has been demonstrated. The results exhibited that the prepared NiCo 2 S 4 electrodes have low charge transfer resistance, and a high specific capacitance of 1330.0 F g −1 at a current density of 1.0 A g −1 . Furthermore, a hybrid supercapacitor was assembled using activated carbon (AC) as the anode material and NiCo 2 S 4 nanorods as the cathode material, and the resulting NiCo 2 S 4 //AC device exhibits an impressive energy density of 27.1 Wh kg −1 at a power density of 1.6 kW kg −1 . This work demonstrates a vision for fabricating a microcrystalline NiCo 2 S 4 cathode under ambient temperature and pressure for hybrid supercapacitors.
研究领域:
材料科学
·
能源存储与转换
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF SOLID STATE CHEMISTRY
·
2020
·
IF 2.726
Hao Tang,Ying Xu,Xianhua Cheng
In this study, Cr 3+ and Mg 2+ co-doped β-NaYF 4 :Yb 3+ /Er 3+ (NYFYE) microcrystals were synthesized for the first time by the facile hydrothermal method . Cr 3+ and Mg 2+ co-doping was confirmed to influence the structure, morphology and UCL property of NYFYE microcrystals. The growth mechanism of NYFYE microcrystals doped with different Cr 3+ and Mg 2+ was discussed in detail. With 16 mol% Cr 3+ and 4 mol% Mg 2+ co-doping into NYFYE, the UC emissions were enhanced to 7 times (green) and 4 times (red) higher than those of the undoped counterpart, and the mechanism was explored by considering the different roles of Cr 3+ and Mg 2+ , the surface quenching and concentration quenching effects. This finding suggests the co-doping of two different impurity ions may be a better approach than corresponding single impurity ion doping for morphology control and UCL intensity enhancement, which is instructive for high performance UC crystals design.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
Sugar Tech
·
2020
·Vol. 22
·期 6
·1138-1147
·
IF 1.198
Li Xin,Deng Ligao,Li Yi,Li Kai
Polylactic acid (PLA) is biodegradable and biocompatible, but some of its functional properties limit its commercial application. To improve the properties of PLA without destroying other useful characteristics, a composite film consisting of microcrystalline cellulose (MCC) and PLA was prepared. In this research, MCC was obtained from bagasse bleached pulp by hydrochloric acid hydrolysis. After being modified by a silane coupling agent (KH550), the MCC was used as reinforcement in the PLA matrix. The degradation performance of the composite film was explored using degradation experiments in which the film was buried in soil. According to the single-factor experiments, the best composite formulation was 3% KH550, 20% KH550-MCC and 15% acetyl tributyl citrate. The results showed that the interfacial compatibility of the MCC/PLA composite films was improved after MCC was modified with KH550. This research showed that the addition of MCC can enhance the degradation rate of MCC/PLA composite films.
研究领域:
材料科学
·
生物工程
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2018
·
IF 3.779
Aihua Zhou,Feng Song,Weijing Yao,Yingdong Han,Feifei Song,Wei Wu,Chengguo Ming,Dandan Ju,Adnan Khan
The carbon-dots/NaLuF 4 microcrystals have been synthesized by the hydrothermal method and bright blue emission from carbon dots is observed in aqueous and solid state under 365 nm excitation. Self-quenching property of the carbon-dots/NaLuF 4 microcrystals under solid state was deeply investigated, by changing the ratio of citric acid (CA) and ethylenediamine (DHE). The results indicate that the carbon dots can be effectively adsorbed and dispersed on the surface of NaLuF 4 microcrystals, suppressing the aggregation of carbon dots. Furthermore, the upconversion luminescence can also be realized under 980 nm laser excitation. From the above observations, the carbon-dots/NaLuF 4 microcrystals not only reveal emission property of carbon dots and NaLuF 4 , respectively, but also optimize the property of carbon dots. It provides a promising new strategy to prevent the carbon dots quenching in solid state and the carbon-dots/NaLuF 4 microcrystals may have potential multi-applications in different fields including temperature sensing, solid-state display lighting as well as security inks.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
Crystals
·
2025
·Vol. 15
·期 5
·451
·
IF 2.4
Chunli Cai,Qian Wang,Changsheng Yin,Xuhuan Li,Rong Yang,Xiaodong Shen,Wenbo Xin
AgCl microcrystals are used in visible light photocatalysis. However, their properties depend strongly on the morphology of the crystals and the degree of exposure of the crystal planes. Despite extensive research conducted on the synthesis of AgCl microcrystals, the majority of existing studies have focused on the stable growth of crystals. The role of Cl−ions concentration as a key factor controlling the microcrystals morphology has not been fully explored, which limits the precise tuning of the morphology of AgCl microcrystals. In this study, AgCl microcrystals with controllable morphology are successfully synthesized by a facile solvothermal method. During the preparation process, ethylene glycol (EG) is utilized as a solvent, while polyvinylpyrrolidone (PVP) is employed as a surfactant. We systematically investigate the etching mechanism of AgCl microcrystals by analyzing the effect of sodium chloride (NaCl) concentration on their morphology. This investigation involves the integration of diverse characterization methods, including scanning electron microscopy (SEM), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS), and geometrical struc-ture analysis. The results demonstrate that Cl−functions as both a surfactant, thereby promoting the nucleation of cubic microcrystals, and as an etchant, selectively etching the crystal surface. The order of selective etching on the crystal surface follows (100) planes > (110) planes > (111) planes. Based on this new mechanism, AgCl microcrystals with various morphologies, such as cube, octopod and dendrite, are successfully prepared, which provides a new idea for the precise design of noble metal halide microcrystals.
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
Inorganics
·
2024
·Vol. 12
·期 12
·327
·
IF 3.1
Ronghua Jian,Tao Pang
This work reports the light-to-heat conversion (LHC) behavior of NaNdF4doped with Sm3+. Due to the cross-relaxation between Nd3+and Sm3+, the improved LHC is obtainable by introducing 5% Sm3+. When the laser power density is only 1.72 W/cm2, the spot temperature of NaNdF4:5%Sm3+powder reaches as high as 138.7 ± 4.04 °C. More importantly, the photoheating response to the pump laser has favorable linear characteristics within a specific power range. A simple physical model is applied to analyze the relationship between photothermal heating and pump power. Finally, the temperature-responsive luminescence anti-counterfeiting is designed by combining the LHC material with the NaYF4:Yb3+/Ho3+/Ce3+microcrystals. This novel strategy only requires two laser beams, and thus is more convenient to apply.
研究领域:
材料科学
·
光学
·
物理化学
✓ 已验证
DOI
高影响因子
Polymers
·
2021
·Vol. 13
·期 22
·3890
·
IF 4.329
Chenlu Jiao,Die Liu,Nana Wei,Jiannan Gao,Fan Fu,Tao Liu,Jian Wang
Porous sustainable cellulose/gelatin/sepiolite gel beads were fabricated via an efficient ‘hydrophilic assembly–floating droplet’ two-step method to remove Congo red (CR) from wastewater. The beads comprised microcrystalline cellulose and gelatin, forming a dual network framework, and sepiolite, which acted as a functional component to reinforce the network. The as-prepared gel beads were characterized using FTIR, SEM, XRD, and TGA, with the results indicating a highly porous structure that was also thermally stable. A batch adsorption experiment for CR was performed and evaluated as a function of pH, sepiolite addition, contact time, temperature, and initial concentration. The kinetics and isotherm data obtained were in agreement with the pseudo-second-order kinetic model and the Langmuir isotherm, with a maximum monolayer capacity of 279.3 mg·g−1for CR at 303 K. Moreover, thermodynamic analysis demonstrated the spontaneous and endothermic nature of the dye uptake. Importantly, even when subjected to five regeneration cycles, the gel beads retained 87% of their original adsorption value, suggesting their suitability as an efficient and reusable material for dye wastewater treatments.Keywords:microcrystalline cellulose;gelatin;sepiolite;beads;dye;adsorption
研究领域:
环境科学
·
材料科学
✓ 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）