INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2023
·
IF 4.2
Daoyin Liu,Jinnan Guo,Jiliang Ma,Cai Liang,Xiaoping Chen
Fluidized bed coating is an efficient technology for creating outer shell layers of particles, where the formation of the shells is affected by various factors, such as raw material properties, process parameters, and equipment geometry. In this study, the effects of seed particle properties, including particle sizes, the mass of bed material, and particle density, on the properties of the coating shells are investigated. First, agglomeration tests are screened to determine the appropriate range of coating conditions within which a layer growth mode is established. Then, the coating tests are carried out, showing that, given the same fluidization number, by increasing the seed particle size or density or increasing the mass of bed material, the drying conditions are improved, resulting in a smaller porosity and denser structure of the coating shells. The coating uniformity is influenced by particle circulation. If the mass of the bed material is too small or the seed particle size or density is too large, the circulation uniformity of the seed particles is affected, which has a negative effect on the coating uniformity. Finally, the influencing mechanisms on shell porosity and particle uniformity are summarized, which can be helpful to the modeling of spray coatings in future studies.
研究领域:
化学工程
·
制药技术
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2024
·
IF 5.8
Guo-Juan Wang,Qiang-Qiang Zhu,Gan-Yu Cai,Yue Zhai,Shuang-Qiang Fang,Juan Kang,Le Wang
The realization of high-quality laser-driven white light remains challenging due to the limited heat dispersion and inconsistent light uniformity of color converters. In this study, ZnO particles with high thermal conductivity and a high index of refraction were induced into phosphor-in-glass (PiG) films to form a Y 3 Al 5 O 12 (YAG):Ce 3+ -ZnO composite structure. The influences of ZnO particles on the luminescence, optical properties, thermal dissipation performance, and light uniformity of PiG films were studied in detail. Benefiting from the improved thermal dissipation, the luminescence saturation threshold of the YAG:Ce 3+ PiG film was improved from 10.97 to 12.96 W/mm 2 , and the luminous flux was improved from 1271 to 1468 lm. The increased light scattering attributed to ZnO particles also effectively dispersed both laser and emitted light. This significantly enhanced the angular consistency of the color rendering index (Ra) and correlated color temperature (CCT). It indicates that the YAG:Ce 3+ -ZnO composite PiG film would be an interesting color converter for producing high-quality laser-driven white light.
研究领域:
材料科学
·
光学工程
·
发光材料
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2024
·
IF 3.8
Ke Xiang,Hui-Hui Ping,Zhen-Liang Xu,Liwei Zhuang,Yong-Jian Tang
Heat curing is an essential step for industrial-scale fabrication of polyamide nanofiltration membranes, which can improve the membrane stability and promote the membrane element encapsulation feasibility, but thermal stresses cannot be avoided during this process. In this study, oven and microwave were used to cure nanofiltration membranes, and the results showed that compared with oven heat curing, the flux dispersion of nanofiltration membranes cured using microwave heat curing was reduced from 0.318 to 0.093, and its Na2SO4 rejection dispersion was reduced from 0.063 to 0.005, providing a tremendous improvement in the uniformity of nanofiltration membranes. The effect of the thermal stress distribution on the uniformity of nanofiltration membranes during heat curing was elucidated by numerical simulations. The fast microwave heating speed and uniform temperature distribution reduced the defects of the PA layer due to uneven thermal stress distribution. In conclusion, this study demonstrated the effect of thermal stress on membrane uniformity in different thermal curing modes, which provides good prospects for the application of microwaves in the field of nanofiltration membranes.
研究领域:
材料科学
·
环境工程
✓ 已验证
产品关联
DOI
高影响因子
Materials Research Express
·
2019
·Vol. 6
·期 11
·115554
·
IF 1.449
Tao Wang,Xiaoou Sun,Duanting Yan,Guodong Zhang,Dejun Wang,Jing Leng,Runru Liu
In this work, the effect of grain size and uniformity of the precursor powder on the electrical property of ceria based electrolytes was investigated. Gadolinia-doped ceria (GDC) samples were treated under different calcination temperatures (600 °C and 1300 °C), where their grain size and uniformity were adjusted by varying the ratio of 1300 °C powder in precursors. The phase composition, morphology and conductivities of mixed GDC samples were characterized by x-ray diffraction (XRD), scanning electron spectroscopy (SEM) and AC impedance, respectively. XRD results revealed that all GDC samples are single cubic fluorite-type structures. As the content of 1300 °C powder increased, the grain boundary conductivity first dropped markedly to the minimum at the ratio x = 5% and then basically unchanged, whereas no significant change was observed in bulk conductivity. Our study demonstrated that the ratio of the higher calcination temperature powder in the mixed precursor powder gave rise to the variation of grain size uniformity and the electrical properties of GDC samples.
研究领域:
材料科学
·
固态离子学
✓ 已验证
DOI
高影响因子
JOURNAL OF THE CERAMIC SOCIETY OF JAPAN
·
2021
·Vol. 129
·期 3
·159-167
·
IF 1.224
Yonghuan HAN,Liwen YAN,Shichen XIE,Tao XU,Wei JING,Feng HOU
Nd3xY3−3xAl5O12 (Nd:YAG) powders with high uniformity were synthesized by reverse-titration co-precipitation method. The precipitation formation process and dispersion mechanism of Nd:YAG precursor in co-precipitation process were analyzed, and the influence of the preparation technology on the dispersion of powders was explored by adjusting the concentration of precipitator, alcohol-water solvent and ratio of composite dispersant. In addition, through the analysis of the precursor calcination process, combined with SEM and particle size analysis, it is shown that, under optimum processing conditions, the powders have excellent particle uniformity, narrow particle size distribution and appropriate crystal size when calcined at 1150 °C for 2 h.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2021
·
IF 7.312
Weilin Zhang,Jianqiang Wang,Xiaolan Geng,Li Liu,Fu Liu
Interfacial polymerized polyamide composite nanofiltration membrane has been widely used in wastewater treatment. Despite its high selectivity towards water and solutes, differentiation of solutes with similar size is still a great challenge. Herein, we propose that polyamide nanofiltration membrane with uniform and tunable pores and sub-nm precision selectivity can be achieved through electrospraying strategy via controlling relative humidity (ratio of practical vapor pressure P 1 and its saturated vapor pressure P s ). The enhanced relative humidity facilitated the dispersion of piperazine (PIP) monomers on substrate and the reaction with trimesoyl chloride (TMC). The membrane (M78) fabricated at high humidity (70%-80%) exhibited more uniform pore size and narrower size region (0.26 nm-0.49 nm) at a designed rejection difference (e.g., 50%) compared with the membrane (0.26 nm-1.0 nm) obtained at low humidity (30%-40%). Membrane selectivity (e.g., Na 2 SO 4 and NaCl) was an order of magnitude high when humidity increased from 30%-40% to 70%-80%. The current study offered a facile and effective strategy for fabricating polyamide nanofiltration membrane with uniform pores and sub-nm selectivity.
研究领域:
材料科学
·
环境工程
·
分离技术
✓ 已验证
产品关联
DOI
高影响因子
Laser & Photonics Reviews
·
2022
·Vol. 16
·期 8
·2100699
·
IF 10.947
Shuchen Shi,Wenhao Bai,Cunjian Lin,Tongtong Xuan,Guoyan Dong,Fan Huang,Rong-Jun Xie
Quantum dot color conversion films (QD-CCFs) are proposed for use in full-color micron-sized light-emitting diode (micro-LED) displays, but quickly and precisely evaluating their optical quality and identifying the bad pixels among them remain challenging. In this work, microscale fluorescence spectroscopy (MFS) is demonstrated to investigate the photoluminescence uniformity and stability of red-emitting CdSe/CdS/ZnS QD-CCF pixels prepared by high-resolution inkjet printing. The photoluminescence (PL) intensity imaging, together with the PL spectrum, lifetime imaging, and time-dependent PL intensity curve, enables accurate analysis of the luminescence uniformity and thermal and light stability of QD-CCFs. The coffee rings in QD-CCF pixels can be clearly identified by MFS, which are missed by a conventional fluorescence microscope. It thus provides feedback for tailoring the composition and properties of ink to eliminate coffee rings or other defects. The combination of MFS with machine learning will likely realize the “massive detection” of QD-CCFs for micro-LEDs.
研究领域:
材料科学
·
光学工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2021
·Vol. 9
·期 28
·15714-15723
·
IF 12.732
Chenhui Li,Sunkai Xu,Ming Jin,Decheng Wan
Ultrasmall and uniform gold nanoclusters (AuNCs), either freestanding or supported, are usually indirectly available unless mediated with abundant strong ligands, but strong ligands usually suppress the catalytic activity towards certain chemical reactions. The dilemma is that a weaker ligand/mediator allows better catalytic activity but tends to mediate larger gold nanoparticles (AuNPs) and vice versa. Here we show a strategy to overcome this issue in the case of supported AuNCs. When trace amounts of moderately strong ligands of thioethers are introduced into sphere-like polyamines patched on a support, uniform and highly catalytically active AuNCs are directly available. Experimentally, in the presence of a porogen, suspension polymerization of 4-vinylbenzyl chloride with divinylbenzene affords mesoporous beads. The exposed benzyl chloride groups on the beads are replaced by a-few-thioether-modified branched polyethylenimine (PEI) molecules. The modified PEI molecules appear as patches (diameter of 1.86 nm) on the support. Uniform AuNCs (e.g. 1.6 ± 0.1 nm) are obtained from the cooperation of several factors: PEI sequesters and in situ reduces the chloroauric acid species; the trace thioethers enhance nucleation of Au atoms; the patch shapes the AuNCs. At an optimal thioether level of 1 mol% (based on amino units), AuNCs show the best catalytic performance, with a turnover frequency (TOF) as high as 354 h−1 available. Analysis suggests that only 1.1% of the dosed thioether groups have a chance to come into contact with the AuNCs. As a result, an ultralow dosage level of 0.12 ppm for AuNCs in a reaction system conducts 98% reductive conversion of 4-nitrophenol within 17 min, and the catalyst is facilely recyclable.
研究领域:
材料科学
·
催化化学
✓ 已验证
DOI
高影响因子
MATERIALS CHARACTERIZATION
·
2024
·
IF 4.8
Yijian Liang,Haohui Ou,Benxuan Li,Wenjing Zhang
Bilayer (BL) two-dimensional transition metal dichalcogenides (TMDs) exhibit excellent properties in carrier mobility , state density, and room temperature stability, which attract considerable attention. However, previous efforts on synthesis BL TMDs have lacked homogeneity and control over the number of layers. Here, we demonstrate an effective and controllable approach to synthesize highly uniform 3R phase BL MoS 2 on a c-plane sapphire substrate . The number of MoS 2 layer can be controlled by adjusting the confinement distance, sapphire step height (annealing temperature), and growth temperature. These influencing factors have been thoroughly investigated. Raman and PL analyses demonstrate bilayer properties and remarkable uniformity. SHG and HAADF-STEM measurements reveal 3R stacking structure of BL MoS 2 . Furthermore, field-effect-transistor (FET) devices fabricated using BL MoS 2 domains exhibit high carrier mobility and on/off ratio. This work provides an efficient method for layer-controlled MoS 2 growth and offers new insights into the growth mechanism of BL MoS 2 .
研究领域:
材料科学
·
物理化学
✓ 已验证
DOI
高影响因子
REVIEWS ON ADVANCED MATERIALS SCIENCE
·
2024
·Vol. 63
·期 1
·
IF 3.6
Lulu Zhang,Jing Wang,Qingyi Wang
Size uniformity is a key challenge in the preparation of hydrothermal carbon spheres and a prerequisite for size effect research and many applications of carbon spheres. To solve the scientific problem of low uniformity due to the slow carbonization in traditional preparation of glucose carbon spheres, we propose to add acid/base catalysts to accelerate nucleation, shorten the nucleation time, and improve the size uniformity of carbon spheres. The carbon spheres prepared under base conditions versus acid conditions have higher uniformity and smaller particle size (particle size = 503 nm). This result is due to the faster accumulation of aromatic clusters, shorter nucleation time, and larger number of carbon spheres in alkaline systems. The NaOH-HCSs-based solid acid catalyst as-prepared exhibits excellent catalytic activity, and the esterification rates of levulinic acid and n -butanol maximize to 96.36%.
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
INORGANIC CHEMISTRY COMMUNICATIONS
·
2024
·
IF 4.4
Kewei Wang,Yuhao Bai,Jie Tao,Weijie Hu,Long-Sheng Wang,Meng Zhang,Li-Ming Wu
The crystal size and uniformity of zeolites are crucial for their excellent performance in various industrial applications. Here, by utilizing commercial micrometer-sized zeolites as seeds and adjusting the weight percentage of seeds from 0 % to 5 %, the crystal sizes of silicoaluminophosphate SAPO-34 samples first decrease from 12.47 μm (S0) to 3.04 μm (S4), then increase to 5.34 μm (S5). Correspondingly, their relative crystal size deviations first decrease from 183.32 % to 60.53 %, then increase to 115.17 %, and the crystal size uniformity factors first increase from 0.33 to 1, then decrease to 0.53. The crystal size uniformity factor of sample S4 equals 1, indicating that it exhibits the best crystal size uniformity. This method is also applicable to aluminosilicate zeolites. By adjusting the weight percentage of seeds from 0 % to 3 %, the crystal sizes of ZSM-5 samples first decrease from 13.61 μm (Z0) to 2.49 μm (Z2), then increase to 4.46 μm (Z3); correspondingly, their crystal size uniformity factors first increase from 0.42 to 1, then decrease to 0.71. In addition, this route significantly enhances the yields and relative crystallinities of both SAPO-34 and ZSM-5 zeolites. Specifically, the yield and relative crystallinity of SAPO-34 zeolite increase by 40.71 % and 8.45 % respectively, while the yield and relative crystallinity of ZSM-5 zeolite improve by 24.05 % and 12.55 % individually. Notably, in the methanol to olefins (MTO) reaction, the propylene selectivity to butene selectivity ratio is inversely related to the crystal size; this suggests that crystal size may play a primary role in the formation of propylene and butene, with smaller crystal sizes being more favorable for the formation of propylene compared to butene. Furthermore, sample S4, which has a crystal size uniformity factor of 1 and a crystal size of 3.04 μm, exhibits excellent MTO performance; its catalytic lifetime increases by 69 %, and selectivity for ethylene plus propylene increases by 6.3 % in comparison to conventional sample S0.
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
OPTICS EXPRESS
·
2024
·Vol. 32
·期 17
·29817-29829
·
IF 3.2
Zongtao Li,Zongtao Li,Jiayong Qiu,Xiujuan Liu,Jiasheng Li
To address challenges in enhancing color uniformity and ambient contrast ratio (ACR) in RGB light-emitting diodes (LEDs) without losing efficiency, we developed a scattering-enhanced magnetic manipulation (SEMM) bilayer structure. The effect of the TiO2 scattering layer on improving the LED’s angular intensity non-uniformity (AIN) was studied by ray-tracing simulations and optimized by varying the particle concentration. The magnetic manipulation technique formed the microcolumns and magnetic chains of the Fe3O4 anti-reflective layer, which was optimized by adjusting Fe3O4 particle size, magnetic field strength, and Fe3O4 concentration. The resulting bilayered device significantly increased the ACR by 11.38 times and reduced AIN by 63% compared to conventional graphite-based LEDs, while maintaining high brightness and consistent color quality across angles. This marks a pioneering application of magnetic manipulation in enhancing LED display quality.
研究领域:
光学工程
·
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）