JOURNAL OF MOLECULAR LIQUIDS
·
2019
·
IF 4.561
Pan Zhang,Lemeng Wang,Chunjie Lu,Mengying Li,Shujun Yu,Dong Fu
The surface tensions of 2‑diethylaminoethanol (DEAE)‑ N ‑(2‑aminoethyl)ethanolamine (AEEA), DEAE‑ N ‑methyl‑1,3‑propane‑diamine (MAPA) and DEAE‑1,4‑butanediamine (BDA) aqueous solutions have been measured by using the BZY-1 surface tension meter. The mass fractions of DEAE and AEEA/MAPA/BDA respectively ranged from 0.300 to 0.500 and 0.050 to 0.150. The temperature ranged from 303.2 K to 323.2 K. A thermodynamic equation was proposed to model the surface tension and the calculated results agreed well with the experiments. The effects of temperature and mass fraction of amines on the surface tension were demonstrated on the basis of experiments and calculations. The surface thermodynamics including surface enthalpy and surface entropy of blended amine aqueous solutions were also determined, and their temperature and mass fraction dependences were analyzed.
研究领域:
物理化学
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溶液化学
·
热力学
·
表面科学
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化工材料
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DOI
高影响因子
Advanced Materials Technologies
·
2019
·Vol. 4
·期 9
·1900414
·
IF 5.395
Shuai Zhao,Rong Zhu
Flexible pressure sensors attract wide attentions in recent years for their significant applications in wearable electronics and health monitoring. It is strongly desired that a pressure sensor possesses both low detection limit and wide measuring capability, covering a broad pressure range from Pa to hundred kPa, to meet diverse demands in different applications. This paper proposes a novel flexible pressure sensor based on thermosensation, using a multilayered and graded-porosity polydimethylsiloxane/silver nanoparticle sponge as piezo-thermic transduction. The sensor exhibits a high sensitivity, a low detection limit of 4.1 Pa, and a wide measuring range up to 200 kPa, which leads to a high range-to-limit ratio of about 50 000. The pressure sensor is monolithically integrated with a temperature sensor and dissolves temperature-compensation. The unique combination of properties makes it feasible to monitor various human signals from subtle wrist pulse to finger tapping pressure and foot stepping pressure by a single device, which shows competent capabilities for multifarious applications in wearable electronics and health monitoring.
研究领域:
生物医学工程
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传感器技术
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可穿戴设备
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健康监测
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柔性电子
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转化医学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2022
·Vol. 49
·期 5
·7913-7919
·
IF 5.532
Rui Li,Panlai Li,Guohui Wei,Jiehong Li,Yawei Shi,Ye Wang,Shaoxuan He,Yuanbo Yang,Wenge Ding,Zhijun Wang
Developing novel optical thermometry with ultrahigh relative sensitivity and temperature resolution has become a cutting-edge topic. For this purpose, under obeying Boltzmann distribution , a series of Li 2 Zn 0.9992-x A x Ge 3-y B y O 8 :0.08% Cr 3+ (B= Sc 3+ , In 3+ , A = Si 4+ ) phosphors were studied, which the luminescence intensity ratio between the transition of 4 T 2g → 4 A 2g emission and the R line based on thermally coupled energy levels constitutes a temperature sensing work with a relative sensitivity of 9.46% K −1 , 9.73% K −1 , and 10.38% K −1 , respectively. It is worth mentioning that the luminescence intensity of the R line (peak 1) increases significantly with the increase of temperature, while the transition of 4 T 2g → 4 A 2g (peak 2) with high intensity at low temperature gradually quenching, and this opposite trend is an important advantage for the design of excellent thermometers. Compared the best relative sensitivity of Li 2 Zn 0.9992-x A x Ge 3-y B y O 8 :0.08%Cr 3+ (B= Sc 3+ , In 3+ , A = Si 4+ ) with the crystal field Dq /B, it can be concluded that relative sensitivity increasing gradually with decreasing the intensity of crystal field. Finally, by testing the stability of the sample at 50 K, a thermal resolution of 0.082 K, 0.080 K and 0.077 K was obtained, respectively, which is one of the best thermal resolutions so far, while the repeatability of the sample stability at 50 K and 300 K cycles was higher than 99%. Our work is expected to provide guiding insights for optimizing the sensitivity of Cr 3+ -based luminescence intensity ratio thermometers.
研究领域:
材料科学
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光学传感
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固体物理
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低温物理学
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功能材料
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发光材料
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DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2015
·Vol. 132
·期 18
·
IF 1.768
Hongchuan Wu,Zhiguo Li,Libin Zhu,Jiyou Gu
Aqueous polyurethane micelles from 2,4,6-trichlorphenol blocking terminal-isocynate pre-polymer were prepared which could be de-blocked at low temperature. The prepared aqueous blocked polyurethane micelles (BPUMs) were uniform and spherical micro-particles. The particle size was decreased with increase of the DMPA content, while it was enlarged at first and then gradually decreased by increasing R -value. The stability of the micelles was affected by the R value, blocked efficiency and DMPA content. HDI-BPUMs were more stable than HDI-BPUMs at the same condition. The stability was further researched by the zeta potential combining with technique and viscosity tracking method, and the initial zeta potential be used as the stability criterion. In addition, a stabilization mechanism of the micelles was proposed. TCP-blocked TDI-BPUMs could be initially de-blocked at about 75°C and TCP-blocked HDI-BPUMs was de-blocked at about 80°C. The de-blocking temperature could be further reduced in the presence of catalyst, but it was scarcely affected by the change of R -value and DMPA content. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132 , 41908
研究领域:
高分子化学
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胶体与界面科学
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材料化学
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功能材料
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纳米材料
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DOI
高影响因子
Advanced Materials Technologies
·
2019
·Vol. 4
·期 10
·1900426
·
IF 5.395
Peng Bi,Xiaowei Liu,Yang Yang,Ziyu Wang,Jing Shi,Gaomin Liu,Fangfang Kong,Benpeng Zhu,Rui Xiong
Wearable devices have become very important for collecting health information and monitoring the condition of seriously ill patients. However, most recently developed wearable devices can only monitor limited signals within a very small range of values. A novel sensor is fabricated by modifying the surface of polyimide nanowires with silver nanoparticles. These nanowire sensors can sense both pressure and temperature changes and have antimicrobial properties. The fabricated sensor can detect a wide range of pressure variation from 5 KPa to 100 KPa. A theoretical model is developed to explain the sensing mechanism of the silver-nanoparticle-modified polyimide nanowires. The experimental and theoretical results for the nanowires are in good agreement. By attaching these sensors to human joints and fingers, real-time information can be detected for human motion, such as walking or holding a hot cup of water. The excellent performance of this device shows that it has great potential for use in artificial skins for detecting temperature and human motion.
研究领域:
生物医学工程
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纳米医学
·
柔性电子
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智能材料
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转化医学
·
可穿戴传感器
✓ 已验证
DOI
高影响因子
MATERIALS RESEARCH BULLETIN
·
2019
·
IF 3.355
Yanqiu Zhang,Sai Xu,Xiangping Li,Jinsu Zhang,Jiashi Sun,Haiping Xia,Ruinian Hua,Baojiu Chen
Novel nanoplatform with excellent photothermal conversion and temperature feedback are preferable in clinical photothermal therapy (PTT). In this work, a hybrid of NaYF 4 :Er 3+ ,Yb 3+ @NaYF 4 upconversion nanoparticles (UCNPs) conjugated with gold nanorods (GNRs) was fabricated in order to achieve effective photothermal conversion and excellent temperature detection. In this nanoplatform, the GNRs as photo-activated nano-heaters could effectively convert the 808 nm photoenergy into heat, meanwhile UCNPs as 980 nm triggered temperature probe could read the temperature in an exact microdomain where the nanocomposite was located at. The effects of excitation source, GNRs concentration and power density on photothermal conversion were investigated. In addition, the difference between eigen temperature of nanoparticles and solution temperature, and the potential for temperature feedback were analyzed under double lasers excitation. Moreover, the photothermal conversion efficiency was experimentally confirmed from thermodynamic analysis. It was found that the nanocomposite can be an excellent nanoplatform for potential application in advanced PTT.
研究领域:
生物医学工程
·
纳米医学
·
肿瘤治疗
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光热疗法
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分子影像
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热疗监测
·
转化医学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·Vol. 50
·期 9
·15202-15208
·
IF 5.1
Xiong Huang,Pengfei Wang,Jianwei Zhao,Jun Yang,Zhenxiao Fu,Xiuhua Cao,Lei Zhang,Shuhui Yu,Rong Sun
As a dielectric material , BaTiO 3 -based ceramics are desirable for high performance ultra-thin multilayer ceramic capacitors (MLCCs) application. In this work, BaTiO 3 -based dielectric ceramics with superior dielectric properties were synthesized using a reducing atmosphere sintering process . It is found that the contribution of “wet" grain-boundary diffusion become significant as the oxygen partial pressure increases, resulting to a larger grain size and higher permittivity. Especially, for the specimen sintered in higher oxygen partial pressure , the stable temperature coefficient of capacitance (TCC) is dominated by irreversal domain due to the increase of super-lattice phase. Samples with higher oxygen partial pressure exhibit a higher permittivity of 2700 and better permittivity-temperature stability. Furthermore, ultra-thin MLCCs with thickness of 1 μm and capacitance of 10 μF and the TCC of X7R were successfully fabricated. This work provides a comprehensive explanation demonstrating upon the significant roles of grain size and defect engineering in the dielectric performance in BaTiO 3 -based ceramics, and points out an avenue to obtain excellent permittivity-temperature stability in ultra-thin MLCCs.
研究领域:
材料科学
·
电子陶瓷
·
介电材料
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固态物理
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功能陶瓷
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电容器技术
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DOI
高影响因子
MATERIALS RESEARCH BULLETIN
·
2022
·
IF 5.6
Min Yang,Yujia Yan,Enzhou Liu,Qian Sun,Jun Fan
In recent years, all-inorganic perovskite has been extensively studied due to its excellent photoelectric properties, but the application of Cs n PbBr 2+ n perovskite with excellent stability in the field of chemical sensing has yet to be developed. Herein, Cs 4 PbBr 6 /CsPbBr 3 with good stability was successfully prepared by controlling the synthesis temperature to 100 ° C. The fluorescence intensity of Cs 4 PbBr 6 /CsPbBr 3 exhibited 2,4-dinitriphenylhydrazine (DNPH) concentration-dependent characteristics and could be used for sensing DNPH based on the dynamic quenching process triggered by the collision between Cs 4 PbBr 6 /CsPbBr 3 and DNPH. A good linear model was established based on the detection signal and DNPH concentration in the range of 0.05∼30 mg/L and the detection limit was 0.033 mg/L. This method was applied to detect DNPH in soil and tap water samples with satisfactory results obtained. Therefore, this research broadens the application of Cs n PbBr 2+ n in the field of quantitative detection and is expected to be developed into a fluorescent sensor for the detection of hydrazine substances.
研究领域:
分析化学
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材料科学
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环境监测
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传感器技术
·
光电子学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Haisheng Chen,Wenwen Chen,Jiaying Shen,Xiaona Du,Tianhong Zhou,Zhengang Dong,Taiyu Bian,Jiaxing Guo,Yiyang Wen,Yuanlin Liang,Zhenping Wu,Yang Zhang
Developing smart luminescent materials with desirable and tunable characteristics has always been an overriding priority of fluorescence technology. However, huge challenges encompass the single functionality of the luminescent materials and the traditional chemical synthetic techniques with rigorously controlling over the miscellaneous experimental conditions and variables. Herein, the lanthanide-doped bismuth-layered ferroelectric (Na 0.5 Bi 0.5 ) 0.96 Er 0.04 Bi 2 Nb 2 O 9.02 has been prepared to be utilized as a platform that not only serves the in-situ and reversible tailoring of the upconverted emission via physical methods, but also enable the versatile functionalities such as photomemory and multi-modal temperature sensing. High luminescent contrast that can reach up to 83.7 % before and after the 405 nm irradiation has been realized on the basis of the photochromic phenomenon of the as-prepared (Na 0.5 Bi 0.5 ) 0.96 Er 0.04 Bi 2 Nb 2 O 9.02 sample, and the fundamental application in the photomemory has been exhibited. Moreover, the performances of triple-mode thermometry built on the fluorescent intensity ratio techniques ( 2 H 11/2 / 4 S 3/2 and 4 S 3/2 / 4 F 9/2 ) as well as the lifetime of the 4 S 3/2 excited state of the Er 3+ ion have been investigated in carefulness, with the maximal relative sensitivities of 1.22 % K −1 at 300 K, 0.92 % K −1 at 510 K, and 0.18 % K −1 at 450 K, respectively. Our results provide significant insights into the methodology of physically modulating the upconversion luminescence, and offer a glamorous pathway for multifunctional high-end applications.
研究领域:
材料科学
·
光学工程
·
功能材料
·
纳米光子学
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传感技术
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固态物理
·
智能材料
✓ 已验证
DOI
高影响因子
Nanoscale
·
2019
·Vol. 11
·期 36
·16907-16918
·
IF 6.97
Hong Lin,Jian Mao,Minchao Qin,Zhilong Song,Wanjian Yin,Xinhui Lu,Wallace C. H. Choy
While red is one of the primary colors for display applications, the investigation of visible red emitting perovskites, particularly 2D perovskites, is relatively limited. In this work, we demonstrate a single-phase Ruddlesden–Popper quasi-2D (C3H7NH3)2CsPb2I7 perovskite for red color LEDs. Through increasing the annealing temperature of (C3H7NH3)2CsPb2I7 perovskite thin films, we have successfully achieved tunable emission wavelengths from 654 to 691 nm. Equally important, for all the quasi-2D perovskite LEDs, once the annealing temperature is fixed, the emission spectrum is independent of bias voltages, which is very important for their use in lighting and displays. With the analysis of the crystallinity, morphology, and thermodynamic stability of the quasi-2D perovskite, we find that the obtained (C3H7NH3)2CsPb2I7 perovskite is a single-phase quasi-2D perovskite with only n = 2 phase. Besides, we found that the red shifting of emission wavelength is caused by the increase of perovskite crystal size while increasing the annealing temperature. Our results also show that the temperature-induced color tunability can be applied to a series of quasi-2D perovskites with different alkylammonium cations. Importantly, we find that short alkylammonium spacers offer better electrical properties for efficient current transport and high performance in LED applications. This work contributes to controlling the optoelectronic properties of quasi-2D perovskites via controlling their crystal growth as well as paves the way to realize practical lighting and display applications of perovskite LEDs.
研究领域:
材料科学
·
光电功能材料
·
半导体器件
·
纳米结构材料
·
固态照明
✓ 已验证
DOI
高影响因子
POLYMER
·
2021
·
IF 4.43
Lu Shi,Wei Liu,Yanhu Xue,Mei Hong,Xiangling Ji
Temperature Rising Elution Fractionation (TREF) is effective for separating polyolefin resins according to crystallizability. A relatively low isothermal crystallization temperature is necessary to fractionate poly(1-butene) (PB-1) resin because of its slow crystallization kinetics . This study aims to investigate the influence of isothermal crystallization temperature of TREF on the fractionation and chain microstructure of eluted fractions for one poly(1-butene-co-ethylene) with 5.8 mol% ethylene. The resin is fractionated using P-TREF under four different isothermal crystallization temperatures, i.e. 0 °C, −5 °C, −10 °C, and −30 °C, and then the fractions are characterized by high-temperature gel permeation chromatography (HT-GPC), 13 C nuclear magnetic resonance spectroscopy ( 13 C NMR), and differential scanning calorimetry (DSC) to acquire their chain microstructure information. The isothermal crystallization temperature significantly affects the nucleation and growth of the crystals, which consequently results in differences in the relative content of eluted fractions. With the decrease of isothermal crystallization temperature from 0 °C to −30 °C, the copolymer is fractionated more effectively since fractions are more evenly distributed among elution temperatures rather than concentrated at lower elution temperatures. Furthermore, the isothermal crystallization temperature influences the chain microstructure of fractions obtained at the same elution temperature, which are different in ethylene content, isotacticity, and average sequence length. The distribution of ethylene content and isotacticity becomes broader with the decrease in isothermal crystallization temperature. Lower isothermal crystallization temperature is conducive to effective separation of the fractions with weak crystallizability. These results are of great significance for the selection of fractionation conditions and chain microstructure analysis of poly(1-butene-co-ethylene) resins.
研究领域:
高分子化学
·
材料科学
·
聚合物表征
·
热分析
·
核磁共振波谱学
✓ 已验证
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
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
·
胶体与界面科学
·
材料化学
·
石油工程
·
表面活性剂化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）