JOURNAL OF PHARMACEUTICAL AND BIOMEDICAL ANALYSIS
·
2010
·Vol. 52
·期 4
·615-619
·
IF 2.453
Shenguang Ge,Mei Yan,Xiaoliang Cheng,Congcong Zhang,Jinghua Yu,Peini Zhao,Weiqiang Gao
A simple and convenient on-line molecular imprinted solid-phase extraction flow-injection fluorescence sensor was developed in this study. Florfenicol (FF)-imprinted polymer was prepared by self-assembly with acrylamide (AM) as functional monomer and ethylene glycol dimethacrylate (EGDMA) as cross-linker. The binding characteristics of the imprinted polymer to florfenicol were evaluated by equilibrium binding experiments, and the morphology of the imprinted polymer was studied by scanning electron microscope (SEM). Fluorescence intensity of 3-p-nitrylphenyl-5-(2′-sulfonophenylazo) rhodanine (4NRASP) and bovine serum albumin (BSA) was inhibited by FF. Under optimum conditions the intensity of fluorescence shows a linear relationship with the concentration of FF over the range of 1.2 × 10 −6 to 2.6 × 10 −5 g mL −1 with a regression equation of Δ I = 23.54 + 17.86 c ( c 10 −6 g mL −1 ) ( r = 0.9965, n = 6). The low detection limit of FF was found to be 3.4 × 10 −7 g mL −1 according to 11 parallel determinations for the blank solution. The relative standard deviation for the determination of 2.0 × 10 −6 g mL −1 FF solution was 3.5% ( n = 11). This proposed sensor could be satisfactorily applied to the determination of FF in liver and meat samples.
研究领域:
分析化学
·
药物残留检测
·
食品安全
·
分子识别
·
环境监测
·
兽药代谢
✓ 已验证
DOI
高影响因子
CARBOHYDRATE POLYMERS
·
2018
·
IF 5.158
Xin Zheng,Fang Huang,Lihui Chen,Liulian Huang,Shilin Cao,Xiaojuan Ma
Three ionic liquids (ILs) with increasing dissolution power, 1-butyl-3-methylimidazolium chloride ([Bmim][Cl]), 1-allyl-3-methylimidazolium chloride ([Amim][Cl]), and 1-ethyl-3-methylimidazolium acetate ([Emim][Ac]), were selected for cellulose dissolution and film preparation through regeneration. The physical properties of the films were investigated, and the correlation between the IL used and the film properties was evaluated. The results indicated that the superior cellulose dissolution system, [Emim][Ac], had the most difficult regeneration process (i.e., more time was required for gel formation), followed by [Amim][Cl], and [Bmim][Cl]. On the other hand, the film produced from [Amim][Cl] had the highest crystallinity, transparency, and tensile strength, followed by the films produced from [Bmim][Cl] and [Emim][Ac]. It was inferred that stronger and more ordered molecular arrangements and inter-molecular interactions preferentially occurred during cellulose regeneration from [Amim][Cl] than during cellulose regeneration from [Bmim][Cl] and [Emim][Ac].
研究领域:
高分子科学
·
材料化学
·
纤维素化学
·
绿色溶剂
·
薄膜材料
✓ 已验证
DOI
高影响因子
APPLIED THERMAL ENGINEERING
·
2016
·
IF 3.043
Min-Jie Liu,Li-Wu Fan,Zi-Qin Zhu,Biao Feng,Han-Cong Zhang,Yi Zeng
In order to study quantitatively the inward solidification heat transfer of a phase change material (PCM) enclosed in spherical capsules, an experimental method was proposed in this Technical Note, which is based upon measurement on the instantaneous volume shrinkage of the PCM during solidification. The shrunk volume was compensated continuously by an extra amount of liquid PCM preserved in a tube, and the descending height in the tube was recorded to calculate the volume shrinkage. Other quantities of interest, solidification fraction and surface-averaged heat flux for example, were readily reduced as single-valued functions of the volume shrinkage. Using 1-tetradecanol as the PCM, the proposed method was realized in laboratory with a stainless steel spherical capsule having an inner diameter of approximately 60 mm. Parallel tests were carried out for a set of three boundary cooling temperatures. It was shown that the measured descending heights are reproducible and are in agreement with the theoretical maximum values approaching the end of solidification. The experimental results were then discussed with an emphasis on the transient variations of solidification and heat transfer. Correlations were obtained for both solidification fraction and surface-averaged Nusselt number with respect to the product of Fourier and Stefan numbers.
研究领域:
热科学与工程
·
储能技术
·
传热传质学
·
材料科学
·
能源工程
✓ 已验证
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2021
·
IF 9.127
Rui Xuan,Jinhui Li,Dongxu Huang,Tao Wang,Bo Zhang,Fangfang Niu,Guoping Zhang,Rong Sun,Ching-Ping Wong
With the continuous development of flexible electronic devices, the corresponding demands for electrochemical storage devices with flexibility and self-healing properties have been raised. However, the current supercapacitors still have great limitations in mechanical and self-healing performance. Herein, flexible and self-healing poly (2-acrylamido-2-methyl-1-propanesulfonic acid) (PAMPSA)/polyvinylimidazole (PVI)/LiCl polyelectrolyte is easily fabricated by a one-step copolymerization . The combined effect of electrostatic interaction and hydrogen bonding significantly enhances the mechanical and self-repairing ability of polyelectrolytes, showing excellent stretchability of 1137%, fracture stress of 154.57 kPa, and high healing efficiency of 91% at room temperature for 24 h. Besides, flexible electrode is prepared by adsorbing poly 3,4-ethylenedioxythiophene/polystyrene sulfonate on a polyurethane sponge. After assembly with a polyelectrolyte, the as-prepared supercapacitor proves excellent electrochemical performance. The area capacitance is 106 mF cm −2 at 50 mV s −1 and excellent cycle stability (97% capacity retention rate after 2000 cycles). In addition, the completely cut off supercapacitor can be successfully restored to 90% of the original capacitance, and still maintain a capacitance retention rate of up to 98% after 1000 cycles. This work provides a possible solution for designing low-cost intelligent and durable electrochemical storage device for smart clothing or electronic skin.
研究领域:
材料科学
·
高分子化学
·
电化学
·
柔性电子学
·
能源存储
✓ 已验证
DOI
高影响因子
Advanced Electronic Materials
·
2021
·Vol. 7
·期 11
·2100548
·
IF 7.295
Yuying Yang,Alei Li,Mengmeng Wei,Youpin Gong,Wei Qin
The understanding of interlayer couplings should be paid much more attention owing to their importance in 2D materials with different layers. Here, through changing the number of layers, the tunability of interlayer coupling by external magnetic field in 2D material based field effect transistors is studied. External magnetic field can increase triplet electron-hole (e-h) pairs to promote interlayer coupling, where larger source-drain current is induced. Moreover, increasing the gate voltage or source-drain voltage, dipole–dipole interaction among the layers will be enhanced to weaken the tunability of source-drain current by magnetic field. This result reveals the magnetic field dependence of interlayer couplings in 2D materials and provides a guidance to develop new functional 2D material devices.
研究领域:
凝聚态物理
·
二维材料科学
·
纳米电子学
·
半导体器件物理
✓ 已验证
DOI
高影响因子
FOOD CHEMISTRY
·
2019
·
IF 5.399
Hui Shen,Mouming Zhao,Weizheng Sun
The influence of pH-induced structural modifications of myofibrillar proteins (MPs) on their interaction mechanisms with pyrazine compounds was investigated. At a lower pH (4.9, 5.5), MPs aggregated to larger particle sizes due to enhanced the protein–protein interactions. The binding with pyrazine compounds was strongly affected by pH and the nature of flavor compounds. MPs exhibited flavor releasing behavior, probably due to protein–protein interactions and surface tension. Fluorescence analysis revealed that the interaction of pyrazine compounds with MPs followed a combination of static and dynamic quenching. The changes in quenching constant ( K sv ) might be attributed to a dynamic quenching, probably due to protein aggregation. The percentages of free 2,5-Dimethylpyrazine (2,5-DMP) were similar to K sv . Thermodynamic parameters indicated that electrostatic interactions and hydrophobic interactions were the major acting forces in the binding of MPs to 2,5-DMP. The binding of 2,5-DMP increased the α-helix content of MPs.
研究领域:
食品科学
·
蛋白质化学
·
风味化学
·
分子互作
·
生物物理化学
✓ 已验证
DOI
高影响因子
ZEITSCHRIFT FUR ANORGANISCHE UND ALLGEMEINE CHEMIE
·
2021
·Vol. 647
·期 6
·681-685
·
IF 1.492
Xieyang Wang,Zhen Dong,Rui Yang,Shengren Zhou,Zhiwen Ye
Two energetic salts of cyclo-N 5 − , O-methylisoure pentazolate ( 1 ) and guanidinoacetic acid pentazolate ( 2 ), were synthesized by metathesis reaction. All the energetic cyclo-N 5 − salts were characterized by single-crystal XRD, IR spectroscopy, 1 H and 13 C multinuclear NMR spectroscopy, thermal analysis (DSC) and elemental analysis. They exhibit good thermal stability with decomposition temperatures of more than 100 °C and they are in excellent agreement with those reported non-metallic salts. Salt 1 also exhibits strong π-π interactions. The standard enthalpies of formation and detonation performances of these salts were calculated using Gaussian 09 and EXPLO5 v6.01 programs. The detonation velocities of compound 1 and 2 are both about 7400 m s −1 and these two salts exhibit low mechanical sensitivity (IS>23 J, FS>220 N). Therefore, in this work, the synthesis of the new pentazolate salts enriches the cyclo-pentazolate salts system, which is conducive to the exploration of more heat-resistant and higher detonation velocities pentazolate salts.
研究领域:
无机化学
·
含能材料
·
热分析
·
结构化学
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2019
·
IF 5.155
Yao Zhu,Huan Yi,Qiaoyan Hao,Jidong Liu,Yuxuan Ke,Zhuo Wang,Dianyuan Fan,Wen jing Zhang
Monolayer WS 2 (1L-WS 2 ) possesses direct band gap, which is beneficial for light emitting applications. However, high quality sample obtained via mechanical exfoliation suffers from ultralow yield of large flakes while large 2D material monolayers synthesized by chemical vapour deposition (CVD) unintentionally induce many defects, resulting in low photoluminescence (PL) intensity. Herein, we firstly control the 1L-WS 2 scalable growth through H 2 introduction at the beginning of the CVD synthesis. Its domain size can be increased from 1 μm up to 20 μm with higher coverage, compared to that synthesized without H 2 introduction. Then, we propose scalable ways to anneal the obtained large 1L-WS 2 in Ar diluted hydrogen sulfide (H 2 S) atmosphere at 750 °C or to treat it with (3-mercaptopropyl) trimethoxysilane (MPS). Its PL intensity can be increased to 12 times by H 2 S or more interestingly to 30 times by MPS, respectively. Our systematic analyses show that the drastic PL improvements are mainly attributed to the reduction of structural defects by H 2 S and MPS, which is facilitated via the H– bond in them. The results help to explore routes to obtaining large-size single crystalline transition metal dichalcogenides monolayer (1L-TMDCs) and intense PL emission.
研究领域:
材料科学
·
纳米科技
·
凝聚态物理
·
表面科学
·
半导体材料
✓ 已验证
DOI
高影响因子
Small
·
2023
·Vol. 19
·期 41
·2302685
·
IF 13.3
Hancheng Ma,Xiang Huang,Luyu Li,Wei Peng,Sheng Lin,Yao Ding,Liqiang Mai
PtTe 2 , a member of the noble metal dichalcogenides (NMDs), has aroused great interest in exploring its behavior in the hydrogen evolution reaction (HER) due to the unique type-II topological semimetallic nature. In this work, a simple template-free hydrothermal method to obtain the phosphorus-doped (P-doped) PtTe 2 nanocages with abundant amorphous and crystalline interface (A/C-P-PtTe 2 ) is developed. Revealed by density functional theory calculations, the atomic Te vacancies can spontaneously form on the basal planes of PtTe 2 by the P doping, which results in the unsaturated Pt atoms exposed as the active sites in the amorphous layer for HER. Owing to the defective structure, the A/C-P-PtTe 2 catalysts have the fast Tafel step determined kinetics in HER, which contributes to an ultralow overpotential ( η = 28 mV at 10 mA cm −2 ) and a small Tafel slope of 37 mV dec −1 . More importantly, benefiting from the inner stable crystalline P-PtTe 2 nanosheets, limited decay of the performance is observed after chronopotentiometry test. This work reveals the important role of the inherent relationship between structure and activity in PtTe 2 for HER, which may bring another enlightenment for the design of efficient catalysts based on NMDs in the near future.
研究领域:
材料科学
·
电化学
·
纳米催化
·
能源材料
·
计算材料学
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2020
·Vol. 9
·期 7
·3985-3994
·
IF 11.301
Ruidi Wang,Bei-Bei Xu,Jiachen Wang,Xue Lu Wang,Ye-Feng Yao
The relationship between the structural characteristics and photocatalytic reaction mechanisms of graphitic carbon nitride (g-C3N4) still remains unclarified at the molecular level, which severely hinders the further development of this field. The present study addresses this issue by employing an innovative strategy to investigate the relationship between the H-containing structures of g-C3N4 and its water splitting properties. The exchangeable and unexchangeable protons of the H-containing groups of g-C3N4 were differentiated by selective deuteration, providing a way to distinguish the hydrophilic and relatively non-hydrophilic H-containing groups of g-C3N4. A combination of advanced solid-state NMR approaches reveals that amino group defects (CN2(NHx)) on the C–N skeleton of the photocatalyst likely serve as hydrophilic active sites for facilitating the photocatalytic hydrogen evolution reaction. Accordingly, the newly synthesized g-C3N4 sample having a high concentration of CN2(NHx) by design demonstrates an enhanced H2 yield by a factor of 17 compared to that of pure g-C3N4.
研究领域:
材料化学
·
光催化
·
固体核磁共振
·
表面科学
·
能源材料
✓ 已验证
DOI
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 53
·42698-42704
·
IF 3.84
Xiaomin Fu,Jiahui Feng,Xingrong Tan,Qiyi Lu,Ruo Yuan,Shihong Chen
Graphite-like carbon nitride nanosheets/3,4,9,10-perylenetetracarboxylic acid hybrids (g-C3N4 NSs–PTCA) were synthesized via π–π conjugate action. Based on novel dual molecular specific recognition of oxyethyl groups to diol and carboxyl to amine groups, a signal-on electrochemiluminescence (ECL) sensor for dopamine (DA) was constructed utilizing g-C3N4 NSs–PTCA as asignal probe and K2S2O8 as a coreactant. Under the optimal conditions, the prepared ECL sensor presented a response to DA with a linear range from 6.0 pM to 30.0 nM. The detection limit (LOD) and limit of quantification (LOQ) of the sensor were 2.4 pM and 7.9 pM, respectively. The g-C3N4 NSs–PTCA signal probe coupling with a novel dual molecular recognition strategy would provide a promising ECL sensing platform for detecting DA sensitively and selectively.
研究领域:
分析化学
·
生物传感
·
分子识别
·
电化学
·
神经递质检测
✓ 已验证
DOI
高影响因子
CATALYSIS TODAY
·
2018
·
IF 4.667
Xiaoyan Liu,Guojun Lan,Panpan Su,Lihua Qian,Tomas Ramirez Reina,Liang Wang,Ying Li,Jian Liu
The hydrogenation of levulinic acid to γ-valerolactone with water as solvent is a crucial reaction for producing fine chemicals. However, the development of highly stable catalysts is still a major challenge. Here, we prepared a Ru nanoparticles incorporated in mesoporous-carbon (Ru-MC) catalyst to achieve high stability in acidic aqueous medium. The Ru-MC showed excellent catalytic performance (12024 h −1 turnover frequency) in the hydrogenation of LA-to-GVL. Compared with Ru supported on mesoporous carbon catalyst (Ru/MC) prepared by conventional wet impregnation method, the Ru-MC showed excellent reusability (more than 6 times) and thermal stability (up to 600 °C). Based on H 2 -TPR-MS characterization, it was proposed that the incorporated structure significantly increased the interaction between Ru nanoparticles and carbon support, which effectively prevent the leaching and sintering of Ru nanoparticles and contributed to increased high reusability and thermal stability of the Ru-MC.
研究领域:
催化化学
·
绿色化学
·
生物质转化
·
纳米材料
·
能源化学
·
有机合成
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）