Chinese Physics B
·
2025
·
IF 1.5
Wenxia Zhang,Weixia Shen,Chao Fang,Ye Wang,Yuewen Zhang,Liangchao Chen,Qianqian Wang,Kenan Li,Biao Wan,Zhuangfei Zhang
Improving the thermal conductivity of diamond-metal composites has always been a significant challenge in the field of thermal management. In this paper, diamond/Al composites were systematically studied, and the influence of holding time (10-120 min) on interface structure and thermal conductivity was discussed. The research results shows that the long-term thermal diffusion sintering can effectively the dense interfacial bonding of diamond/Al composites and enhance the thermal conductivity. The diamond/Al composites with 50 vol% 900 μm diamond attained the highest value of 888.73 W/mK under the sintering conditions of 650 ℃, 50 MPa, and 120 min, nearly 92% of the theoretical value predicted by the Maxwell model. This study establishes that high thermal conductivity can be achieved through long-term thermal diffusion alone, without the complex diamond surface coating and substrate alloying.
研究领域:
材料科学
·
热管理技术
✓ 已验证
产品关联
DOI
高影响因子
Smart Materials and Structures
·
2021
·Vol. 30
·期 11
·115003
·
IF 3.585
Xiaosong Li,Xinxin Li,Lvzhou Li,Tianhui Sun,Yonggang Meng,Yu Tian
Reversible adhesion has great potential in a broad range of applications such as robotic grasping, transfer printing, and precision assembling. Herein, we show a trumpet-shaped controllable adhesive structure capable of grasping and releasing millimeter-sized three-dimensional objects with an instability modulation strategy. Experimental results revealed that the strong grasping capacity via compressing derives from the dual contribution of vacuum pressure and van der Waals interactions at the contact interface, whereas the easy releasing performance via shearing/twisting is facilitated by local unsymmetric cracking and subsequent peeling at the adhesive interface. Finite element analysis validated that external load such as shearing and twisting can dynamically modulate the interfacial stress from a relatively uniform distribution to a severely uneven state through buckling, which changes the crack path and thereby destructs the adhesive interface. Furthermore, the controllable adhesive structure was successfully demonstrated to transfer various three-dimensional objects with durable performances in both air and underwater environments. This work presents a generally applicable and dexterous modulation strategy to achieve tunable adhesion for millimeter-scale and even smaller objects, which promotes the understanding and application of controllable adhesion.
研究领域:
机器人技术
·
材料科学
·
表面工程
✓ 已验证
产品关联
DOI
高影响因子
ANALYTICAL LETTERS
·
2024
·
IF 1.6
Zhixiang Huang,La Chen,Gangqiang Li,Huanhuan Hong,Lvying Kuang,Luhong Wen
The capillary is a widely used atmospheric pressure interface in mass spectrometers that may be heated to enhance the desolvation of ions. In this study, the ion transmission efficiency of a portable ion trap mass spectrometer was investigated using capillaries with different inner diameters and temperatures, different vacuum pressures, and different ion optics designs. Due to the incomplete desolvation and the space charge effect inside the miniature ion funnel, the increase of ion intensities with the inner diameter of the capillary leveled off when the inner diameter of the capillary was larger than 0.37 mm. With the increase of capillary temperature, the ion intensities first increase due to better desolvation and then decrease due to greater diffusion loss. The optimal temperature of the capillary increases with the inner diameter of the capillary and the mass-to-charge ratio of ion. In addition, the pressures of different vacuum stages also exerted remarkable effects on the sensitivity of the portable mass spectrometer. From the perspective of instrument miniaturization, optimal transmission efficiency can be obtained when the first-stage vacuum pressure is maintained from 4 to 6 mbar. For a capillary with an inner diameter of 0.37 mm, the background of mass spectrum can be significantly reduced by replacing the pinhole behind the ion funnel with an off-axis skimmer.
研究领域:
分析化学
·
质谱分析
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2021
·Vol. 11
·期 33
·20081-20088
·
IF 3.361
Lechen Yang,Yan Wu,Feng Yang,Wenhao Wang
As a natural biological material, wood has renewability, biocompatibility, biodegradability and excellent mechanical properties. This research shows a conductive polymer composed of a cellulose-based flexible film constructed from natural wood and carbon nanotubes. Part of the lignin/hemicellulose of the natural wood was removed by the deep eutectic solvent to obtain a cellulose-based flexible film with a porous structure, and then the carbon nanotubes were infiltrated into the cellulose-based flexible film by vacuum pressure impregnation treatment to obtain the final conductive polymer. This conductive polymer has high conductivity and good toughness, and shows good perception ability under a certain range of strain/stress or human activity conditions. In addition, conductive fibers can be prepared by cutting and twisting the oriented cellulose nanofibers of this conductive polymer. The above-mentioned properties of this conductive polymer provide great potential for its development in electrical-related fields.
研究领域:
材料科学
·
纳米技术
·
电气工程
·
生物材料
·
可持续材料
✓ 已验证
DOI
高影响因子
EUROPEAN POLYMER JOURNAL
·
2023
·
IF 6
Xuanye Wang,Lei Yu,Zhengqiang Fan,Guochao Yang,Hongwu Guo
Utilizing bio-based flame retardants like chitosan (CS) and tannic acid (TA) is an effective way to enhance the flame retardancy of wooden products. In this work, the poplar wood was impregnated with composite flame retardants containing CS, TA, Cu (CH 3 COO) 2 ·H 2 O and silane coupling agent (KH550). When KH550 bound these substances together to form a stable compound, a highly efficient flame-retardant wood (wood/CTA-Cu-Si) was prepared under vacuum pressure impregnation. The results of the functional group test show that bio-based flame retardants have been successfully synthesized. The limiting oxygen index (LOI) of the treated sample was reached 31.5%, the sample also passed the V-0 grade in the UL-94 vertical burning test, and in the Cone colorimeter test, the total smoke release was reduced by 50.2% compared to that of the Control. The energy dispersive spectroscopy proved that Cu and Si elements were evenly distributed in the wood before and after combustion. Raman spectra of the residues after the burning of treated wood were compared and it was found that the degree of graphitization of wood/CTA-Cu-Si was significantly increased, which I D / I G reached 1.85. After impregnation, the flame-retardant treated wood sample exhibited no negative effect on mechanical properties. The flame-retardant mechanism was probed and summarized as the Cu and Si synergistic promotion on charring and suppression on heat and smoke release. Simultaneously, the existences of Si-C, Si-O and Si-N strengthened the char layer and enhanced flame retardancy of poplar wood. Such resulted poplar wood with flame retardancy will be an excellent application prospect as engineering biomaterial.
研究领域:
材料科学
·
化学
·
木材科学与技术
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）