CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Zhao Li,Xingyun Jin,Chunfeng Hu,Bo Dai,Yong Ren,Fang Xu,Yong Zhao,Xingwu Yuan
In this work, conventional sintering, hot-pressing sintering, and spark plasma sintering techniques were utilized to simulate the thermal field, thermal-stress field, and thermal-stress-electric field, respectively. The effects of these fields on the microstructure and cation distribution of the (Mg 0.1 Mn 0.1 Co 0.1 Ni 0.2 Ti 0.1 Cu 0.1 Zn 0.2 )Fe 2.1 O 4 ferrite (HEF) material were comprehensively analyzed. The results indicate that in the temperature range of 1000–1100 °C, the thermal field provides the driving force for sintering, promotes grain growth (average particle size: 2→7 μm), and increases crystallinity degree. The stress field brings the particles into close contact with each other, facilitates diffusion, and delays grain growth (0.5→5 μm). The electric field reduces grain boundary energy, causes mass transfer, and makes the grains finer (0.5→0.7 μm) and more uniform. Mathematical model analysis reveals that the thermal field is beneficial to the random distribution of cations, which yields an inversion degree (γ) of about 2/3 and increases the configuration entropy of HEF. The stress field leads to lattice distortion, permits ions with larger radius to occupy tetrahedral positions, and changes the cell parameters and oxygen position parameter of HEF. Finally, the interaction between electric field and crystal charges increases the electrostatic field energy, which promotes the formation of positive spinel structure and maximizes the crystal field stability energy. X-ray photoelectron spectra, Raman spectra, and change in lattice constant confirm the rationality of the mathematical model, and can be used to establish the model of the crystal structure under field effects.
研究领域:
材料科学
·
物理学
✓ 已验证
产品关联
DOI
高影响因子
Nanomaterials
·
2021
·Vol. 11
·期 10
·2694
·
IF 5.076
Kai Li,Dazhi Wang,Fangyuan Zhang,Xiaoying Wang,Hairong Chen,Aibing Yu,Yuguo Cui,Chuanhe Dong
A novel method called tip-viscid electrohydrodynamic jet printing (TVEJ), which produces a viscous needle tip jet, was presented to fabricate a 3D composite osteochondral scaffold with controllability of fiber size and space to promote cartilage regeneration. The tip-viscid process, by harnessing the combined effects of thermal, flow, and electric fields, was first systematically investigated by simulation analysis. The influences of process parameters on printing modes and resolutions were investigated to quantitatively guide the fabrication of various structures. 3D architectures with high aspect ratio and good interlaminar bonding were printed, thanks to the stable fine jet and its predictable viscosity. 3D composite osteochondral scaffolds with controllability of architectural features were fabricated, facilitating ingrowth of cells, and eventually inducing homogeneous cell proliferation. The scaffold’s properties, which included chemical composition, wettability, and durability, were also investigated. Feasibility of the 3D scaffold for cartilage tissue regeneration was also proven by in vitro cellular activities.Keywords:3D printing;electrohydrodynamic jet;thermal field;fluid viscosity;osteochondral scaffold
研究领域:
生物医学工程
·
组织工程
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2025
·
IF 9
Bingxue Huang,Jie Liu,Jia Xie,Rui Tang,Hongyi Zhu,Biyou Peng,Wei Zhang
Photothermal 3D hydrogels have shown great potential for solar-driven desalination. In this study, an integrated 3D photothermal hydrogel evaporator was developed to enhance evaporation performance by leveraging a solar-induced environmental heat field and a concave evaporation surface. The photothermal hydrogel matrix was fabricated by incorporating sodium humate-based photothermal particles (synthesized through the chelation of sodium humate and Cu 2+ ) into a sodium alginate/polyacrylamide hydrogel network. The resulting 3D hydrogel evaporator, featuring a tree-ring structure, achieved a stable evaporation rate of 2.23 kg m −2 h −1 in deionized water for 3 h under one-sun irradiation and demonstrated robust performance in various water bodies, including strong brine and sewage. To further enhance energy input, a commercial photothermal enclosure was integrated to create a surrounding heat field under sunlight. By combining energy from the photothermal particles and the solar-induced heat field, the evaporator with a concave evaporation surface achieved an exceptional evaporation rate of 3.69 kg m −2 h −1 under one-sun irradiation, corresponding to a theoretical solar energy utilization efficiency of 193 %, representing a 65 % improvement compared to pre-integration levels. This work presents a novel strategy for designing high-efficiency solar evaporators, offering significant advancements in sustainable desalination technologies.
研究领域:
材料科学
·
环境科学
·
能源工程
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS CHARACTERIZATION
·
2024
·
IF 4.8
Yunwei Shi,Yichao Ren,Qianglong He,Jinghan Wang,Aiyang Wang,Hao Wang,Weimin Wang,Zhengyi Fu
Functionally graded materials (FGMs) have attracted more and more attention due to their graded changes on composition or microstructure to satisfy some conflicting properties in one component. However, the interfacial stress induced by the composition difference across an interface would degrade the reliability of components and hinder its advancement. Herein, a general process to fabricate continuously and symmetrically graded Si 3 N 4 -based ceramics is designed to address the problem above. By the combination of gaseous gradient diffusion and in-situ gas reaction, the graded ceramics with hard surface and tough core are first prepared under uniformly thermal field. The edge area of graded ceramics exhibits fine microstructure, high hardness (19.82GPa), and low fracture toughness (4.73 MPa·m 1/2 ), while the interior exhibits a distinct difference with coarse grains, low hardness (18.31GPa) and high fracture toughness (6.12 MPa·m 1/2 ). The thickness of continuously graded microstructure is effectively controlled and regulated by optimizing sintering regimes.
研究领域:
材料科学
·
陶瓷工程
·
制造工艺
✓ 已验证
产品关联
DOI
高影响因子
ANALYTICA CHIMICA ACTA
·
2023
·
IF 6.2
Kailiang Zhang,Wei Xiang,Jiuqing Liu,Zhijie Xie
Flexible droplet transportation and coalescence are significant for lots of applications such as material synthesis and analytical detection. Herein, we present an effective method for controllable droplet transportation and coalescence via thermal fields. The device used for droplet manipulation is composed of a glass substrate with indium tin oxide-made microheaers and a microchannel with two transport branches and a central chamber, and it's manipulated by sequentially powering the microheaters located at the bottom of microchannel. The fluid will be unevenly heated when the microheater is actuated, leading to the formation of thermal buoyancy convection and the decrease of interfacial tension of fluids. Subsequently, the microdroplets can be transported from the inlets of microchannel to the target position by the buoyancy flow-induced Stokes drag. And the droplet migration velocity can be flexibly adjusted by changing the voltage applied on the microheater. After being transported to the center of central chamber, the coalescence behaviors of microdroplets can be triggered if the microheater located at the bottom of central chamber is continuously actuated. The droplet coalescence is the combined effect of decreased fluid interfacial tension, the shortened droplet distance by buoyancy flow and the increased instability of droplet under the elevated temperature. The droplet coalescence efficiency is also related to the voltage of microheater, by increasing the voltage from 3.5 V to 7 V, the needed time for droplet coalescence dramatically decrease from 220s to 1.4 s. Finally, by the droplet coalescence-triggered calcium hydroxide precipitation reaction, we demonstrate the applicability of the droplet manipulation method on specific sample detection. Therefore, this approach used for droplet transportation and coalescence can be attractive for many droplet-based applications such as analytical detection.
研究领域:
微流控技术
·
分析化学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Silicon
·
2023
·Vol. 15
·期 10
·4325-4334
·
IF 3.4
Shi Xu,Xu Weibing,Zhou Zhengfa,Ma Haihong,Ren Fengmei
In order to improve the smoke suppression of silicone oil, relatively high nitrogen content silicone oil was synthesized by the reaction of dicyandiamide (DCD) and epoxy-terminated silicone oil (ETSO) and named DCDSO. The molecular structure of DCDSO was characterized by Fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance spectroscopy (NMR). The flame ignition and cone calorimetry test (CCT) were used to investigate the smoke suppression effect of DCDSO. The results showed that the introduction of DCD significantly improved the smoke suppression performance of DCDSO. When the molar ratio of the epoxy group in ETSO and the primary amino group in DCD was 1:1.3, the flame height and the total smoke production were significantly reduced. Thermogravimetric analysis (TGA), thermogravimetric infrared analysis (TG-IR) and thermal field emission scanning electron microscopy (SEM) were used to explore the mechanism of smoke suppression. The mechanism of smoke suppression is that the introduction of DCD reduces the rearrangement decomposition, promotes the free radical oxidation decomposition and the formation of condensed phase, and thus reduces the generation and release of smoke.
研究领域:
材料科学
·
化学工程
·
消防安全
✓ 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）