CERAMICS INTERNATIONAL
·
2017
·Vol. 43
·期 16
·14176-14182
·
IF 2.986
Lin Wang,Benxue Liu,Luyi Zhu,Yongshuai Xie,Yadong Lv,Chonghe Xu,Xiaotong Jin,Xinqiang Wang,Guanghui Zhang,Dong Xu
Polyaceticzirconium (PEZ) sol, which is the precursor of zirconia (ZrO 2 ) continuous fibers, has been synthesized by means of the reaction between zirconium oxychloride octahydrate (ZrOCl 2 ·8H 2 O) and potassium acetate (CH 3 COOK) in methanol. The polymeric structures and the rheological behaviors of the sols with different molar ratios of ZrOCl 2 ·8H 2 O/CH 3 COOK are different and would affect the spinnability and stability significantly. Herein, the polymeric structures and rheological behaviors of the PEZ sols with the molar ratios of 1:1, 1:1.5, 1:1.8 and 1:2 were investigated by Fourier transform infrared (FT-IR), 1 H nuclear magnetic resonance spectrum ( 1 H-NMR), thermogravimetry and differential thermal analysis (TG/DTA) and rheological measurements. The results showed the carboxyl group acted as a chelating ligand instead of bidentate ligand, and the water molecule coordinated to Zr 4+ was deprotoned gradually with the decrease of the molecular ratios. The different polymeric structures lead to a different rheological behaviors of the sols. It is divided into three types, the Newton fluid with a low viscosity produced by the charged linear polymeric structures, the shear thinning fluid with a high viscosity produced by the three-dimensional polymeric structures and the shear thinning fluids with a proper viscosity produced by the linear twining polymeric structures. Through the experimental guidance, we successfully synthesized a sol with suitable viscosity and stability, and used it to fabricate high quality ZrO 2 fibers.
研究领域:
材料科学
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无机化学
·
高分子化学
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纤维工程
·
溶胶-凝胶技术
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DOI
高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
·
2019
·Vol. 27
·期 12
·3053-3059
·
IF 1.911
Nianjun Kang,Dongbo Xu,Weidong Shi
In recent years, the excessive use of antibiotics has become a serious problem for human health. BiVO 4 regarded as one of the most promising visible-light-driven photocatalysts was used to degrade the antibiotics. In this paper, we fabricated Bi/BiVO 4 plasmonic photocatalysts which enhanced the photocatalytic activity of BiVO 4 for degradation of tetracycline (TC) antibiotic. The Bi/BiVO 4 photocatalysts were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy and high-resolution transmission electron microscopy . In addition, the photocatalytic experiment results show that the 0.04-Bi/BiVO 4 sample has the best photocatalytic activity for 2 times than the pure BiVO 4 photocatalyst. The cycle experiments, after four repetitions of the experiments, showed the sample still maintained a high photocatalytic activity. Finally, the photocatalytic reaction mechanism was also studied by free radical capture experiments and electron paramagnetic resonance spectroscopy .
研究领域:
环境化学
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材料科学
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光催化
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纳米材料
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环境污染治理
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药物降解
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DOI
高影响因子
Small
·
2023
·Vol. 20
·期 3
·2306251
·
IF 13.3
Muchun Guo,Ming Liu,Jianbo Zhu,Yuke Zhu,Fengkai Guo,Wei Cai,Yongsheng Zhang,QinYong Zhang,Jiehe Sui
Chemical bonds determine electron and phonon transport in solids. Tailoring chemical bonding in thermoelectric materials causes desirable or compromise thermoelectric transport properties. In this work, taking an example of CaMg 2 Bi 2 with covalent and ionic bonds, density functional theory calculations uncover that element Zn, respectively, replacing Ca and Mg sites cause the weakness of ionic and covalent bonding. Electrically, Zn doping at both Ca and Mg sites increases carrier concentration, while the former leads to higher carrier concentration than that of the latter because of its lower vacancy formation energy. Both doping types increase density-of-state effective mass but their mechanisms are different. The Zn doping Ca site induces resonance level in valence band and Zn doping Mg site promotes orbital alignment. Thermally, point defect and the change of phonon dispersion introduced by doping result in pronounced reduction of lattice thermal conductivity. Finally, combining with the further increase of carrier concentration caused by Na doping and the modulation of band structure and the decrease of lattice thermal conductivity caused by Ba doping, a high figure-of-merit ZT of 1.1 at 823 K in Zn doping Ca sample is realized, which is competitive in 1–2–2 Zintl phase thermoelectric systems.
研究领域:
材料科学
·
凝聚态物理
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无机化学
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能源材料
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热电转换
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DOI
高影响因子
PARTICLE & PARTICLE SYSTEMS CHARACTERIZATION
·
2018
·Vol. 36
·期 1
·1800077
·
IF 4.384
Yiqi Zhuang,Linlin Liu,Xiaoyan Wu,Yu Tian,Xuehong Zhou,Shuping Xu,Zengqi Xie,Yuguang Ma
The “far-field” surface plasmon resonance (FSPR) of metal nanoparticles, which have built a facile way to emission enhancement of red, green, blue, and white with nice reproducibility, has big potential application in solution-processed organic light-emitting diodes (OLEDs). According to the theory of the “far-field” effect, the reflectivity of the metal surface and the phase shift at the reflection play an important role in enhancing ratio, which strongly relate to the size and shape of nanoparticles. In this work, gold nanospheres with different sizes and nanorods are synthesized in order to determine the size and shape effect of FSPR. The results demonstrate that the one with higher reflectivity in a certain range induces a better emission enhancement in the luminous efficiency and the maximum brightness. The nanoparticles with bigger sizes and shape of rods have higher reflectivity, which is consistent with the simulation based on FSPR effect. The phase shifts of different nanoparticles are optimized by the distance between gold nanoparticles and emitters. The metal NPs with a high reflectivity and the applicable phase shift will have big potential for the emission enhancement in OLEDs.
研究领域:
纳米光学
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材料科学
·
光电子学
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表面等离子体学
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有机光电子器件
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DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2013
·
IF 2.144
XiaoDan Zeng,Lin Zhu,FuSheng Zhang,LiYun Feng
The interaction of bovine serum with leucomalachite green (LMG) was investigated by spectroscopic methods . LMG was found to quench the intrinsic fluorescence of BSA by dynamic quenching. High quenching constant suggested that LMG can form a complex with BSA. Binding constant and number of binding site were determined. The thermodynamic parameters suggested the main interacting force is hydrophobic forces . The effect of LMG on the conformation of BSA was analyzed by synchronous fluorescence spectroscopy . RLS spectra were also used to reconfirm the formation of complex between BSA and LMG.
研究领域:
生物化学
·
分子生物学
·
光谱学
·
药物代谢
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蛋白质-配体相互作用
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DOI
高影响因子
FOOD CHEMISTRY
·
2017
·
IF 4.529
Ting Shi,MengTing Zhu,Yi Chen,XiaoLi Yan,Qian Chen,XiaoLin Wu,Jiangnan Lin,Mingyong Xie
Proton nuclear magnetic resonance ( 1 H NMR) and chemometrics were employed to detect the adulteration of camellia oil (CAO) with 3 different cheap vegetable oils. With the intensity of 15 selected 1 H NMR signals as input variables, principal component analysis (PCA) showed good group clustering results for pure and nonpure CAO, but unsatisfied identification accuracy for the adulterated oil types, indicating relatively small difference among those oils. Whereas these difference could be revealed by orthogonal projection to latent structures discriminant analysis (OPLS-DA), with identification accuracy higher than 90%. Partial least squares (PLS) was further applied for the prediction of adulteration level in CAO. With less than 6 variables screened out by variable importance in the projection (VIP) scores as potential key markers, the developed PLS models showed better accuracy. The prediction results for 10 hold-out samples also confirmed that this method was accurate and fast for the detection of CAO adulteration.
研究领域:
食品科学
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分析化学
·
食品安全
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代谢组学
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油脂化学
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DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2014
·
IF 6.007
Xu Yan,Xiyou Wang,Wei Gu,MiaoMiao Wu,Yan Yan,Bo Hu,Guangbo Che,Donglai Han,Jinghai Yang,Weiqiang Fan,Weidong Shi
Single-crystalline AgIn(MoO 4 ) 2 nanosheets have been successfully fabricated by facile hydrothermal method without any surfactants. Subsequently, Ag/AgBr-grafted AgIn(MoO 4 ) 2 nanosheets were synthesized by the in situ photoreduction of AgBr/AgIn(MoO 4 ) 2 composites prepared by a deposition–precipitation method. Under visible light irradiation. The Ag/AgBr/AgIn(MoO 4 ) 2 composites exhibit a strong absorbance in the visible region because of the surface plasmon resonance absorption of Ag nanocrystals. Compared with bare AgIn(MoO 4 ) 2 nanosheets, Ag/AgBr nanoparticles and Ag/AgIn(MoO 4 ) 2 composites, a dramatic enhancement in the degradation rate of tetracycline (TC) is observed over the Ag/AgBr/AgIn(MoO 4 ) 2 composites. The immense enhancement of the photocatalytic activity is attributed to the extended absorption in the visible-light region, effective charge separation, and synergistic enhancement induced by surface plasmon resonance (SPR) in the heterostructured Ag/AgBr/AgIn(MoO 4 ) 2 . This study provides new insight into the fabrication of highly efficient and stable ternary metal molybdate based plasmonic photocatalysts and facilitates their practical application to solve environmental issues. The mechanism for the photodegradation of TC over Ag/AgBr/AgIn(MoO 4 ) 2 is discussed in detail.
研究领域:
材料科学
·
环境化学
·
光催化
·
纳米材料
·
无机化学
·
物理化学
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DOI
高影响因子
JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY
·
2013
·Vol. 51
·期 9
·2016-2023
·
IF 3.543
CaiFei Wang,ChunHua Zhao,JiaQin Sun,SanQing Huang,XiangDong Liu,Takeshi Endo
A fully bio-based benzoxazine, 3-furfuryl-8-methoxy-3,4-dihydro-2H-1,3-benzoxazine (Bzf), has been prepared using guaiacol, furfurylamine, and paraformaldehyde as raw materials. Its chemical structure has been characterized by 1H and 13C NMR, FTIR, and elemental analysis. The polymerization behavior of Bzf in the presence of methyl p-toluenesulfonate (PTSM) has been studied by FTIR and DSC, and the thermal stability of the cured resin has been evaluated by thermogravimetric analysis. It was found that PTSM is a good promoter that serves to avoid thermal decomposition of the bio-based monomer during the curing process at high temperature. In contrast to the situation with neat Bzf, the presence of PTSM (5 mol % for Bzf) significantly improves the polymerization behaviors, including a decrease in the polymerization temperature from 240 to 174 °C, a shortening of the time required to reach the gel point on heating at 200 °C from 47 to 20 min, and an increase in the char yield of the cured resin from 53 to 62%. Moreover, these observed experimental results on the promoting effect of PTSM are interpreted in terms of several possible mechanistic schemes, which involve a catalytic effect on the dissociation of C O bonds in both the coordination ring-opening reaction and the rearrangement from a phenoxy structure to a phenolic structure. © 2013 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013
研究领域:
高分子化学
·
材料科学
·
热分析
·
绿色化学
·
功能高分子
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DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2014
·Vol. 132
·期 8
·
IF 1.64
Jian Chen,Fuhua Huang,Hong Wang,Ya Li,Shengli Liu,Pinggui Yi
Fluorescent nanoparticles with multiplex distinct emission signatures and high brightness by a single wavelength excitation are substantially needed in multiplex bioassays and imaging. In this study, we synthesized fluorescent polymeric nanoparticles incorporated with three polymerizable organic dyes via a one-pot miniemulsion. By altering the doping ratio of three tandem dyes, the nanoparticles display abundant multiple fluorescence such as blue, cyan, green, orange, pink, red etc., together with distinguishable emission signatures under a single wavelength excitation, which were arising from the effective fluorescence resonance energy transfer (FRET) between the three energy-matched dyes. Meanwhile, a large Stokes shift (up to 250 nm) can be generated by taking place multiple FRET cascade mechanism between donor and acceptor fluorophores in nanoparticles, which also suggests broad applications in biological labeling and imaging. Moreover, these nanoparticles are uniform in size, highly bright, excellently photostable, and shown prominent longterm stability. Overall, the novel multicolor fluorescent polymeric nanoparticles augur well for their potential applications in multiplexed bioanalysis and emitting displays. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132 , 41492.
研究领域:
生物医学工程
·
纳米医学
·
分子影像学
·
生物分析化学
·
材料科学
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DOI
高影响因子
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2016
·Vol. 18
·期 29
·19731-19737
·
IF 4.449
Yingna Cui,Jingmei Yin,Changping Li,Shenmin Li,Ailing Wang,Guang Yang,Yingping Jia
The compositions and structures of amine-based functionalized protic ionic liquids (PILs), namely N,N-dimethyl(cyanoethyl)ammonium propionate (DMCEAP) and N,N-dimethyl(hydroxyethyl)ammonium propionate (DMEOAP) have been investigated systematically by IR and 1H NMR spectroscopy and density functional theory (DFT) calculations. Analysis of the IR spectra suggests that both DMCEAP and DMEOAP are composed of neutral and ionized species in the liquid phase, the former one mainly existing in the state of precursor molecules, and the latter mainly as ion-pairs. The ratio of precursor molecules to ion-pairs in the liquid phase depends on the types of precursors, especially the functional groups of cations. 1H NMR spectra indicate that there is a dynamic equilibrium between the neutral and ionized species, probably due to the formation of some intermediates in the PILs. The DFT calculations have been carried out to reveal the conformation, and obtain the corresponding IR and 1H NMR spectra of the neutral and ionized species, so that the theoretical support to the experimental results can be provided. The present study will help understand the properties of PILs and provide guidance for further applications of PILs.
研究领域:
物理化学
·
离子液体化学
·
光谱学
·
理论化学
·
分析化学
·
材料化学
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DOI
高影响因子
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2014
·Vol. 16
·期 23
·11584-11589
·
IF 4.198
Yunyun Huang,Wensheng Lin,Kan Chen,Wenkai Zhang,Xudong Chen,Ming Qiu Zhang
A water-processable blue fluorescent silver nanoparticle@graphene–polymer composite (Ag@G–pNIPAM) consisting of graphene coated with a thermally responsive poly-(N-isopropylacrylamide) (pNIPAM) shell is prepared. The pNIPAM shell swells or collapses as a function of temperature, serving as a means to trap silver nanoparticles in solution and get them sufficiently close to the graphene core to provide fluorescence enhancement based on the local surface plasmon resonance (LSPR) effect. The unique thermoresponsive properties and high enhancement ratio of the material should find application in solution fluorescence enhancers and a variety of biomedical applications, such as cellular uptake, sensing and imaging.
研究领域:
纳米医学
·
生物材料
·
分子影像学
·
生物传感
·
药物递送系统
✓ 已验证
DOI
高影响因子