JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
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2018
·Vol. 30
·期 1
·647-657
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IF 2.324
Xiao Tai,Huang Zu-Sheng,Wang Lingyun,Cao Derong
Three novel dithieno[3,2- f :2′,3′- h ]quinoxaline-based organic dyes ( IQ-C, IQ-D and IQ-F ) with three π-spacers were synthesized and developed for dye sensitized solar cells, where dithieno[3,2- f :2′,3′- h ]quinoxaline was used as electron-withdrawing π-spacers, and 2,3-diphenylquinoxaline or dibenzo[ a,c ]phenazine as auxiliary electron-withdrawing π-spacers. The dye IQ-D with 2,3-diphenylquinoxaline as auxiliary electron-withdrawing π-spacer exhibited higher photocurrent ( J sc ) and photovoltage ( V oc ) than that of the dye IQ-C with 2,3-bis(4-(octyloxy)phenyl)quinoxaline as the additional electron-withdrawing π-spacer, due to the larger adsorption amount of IQ-D . The dye IQ-F with a rigid conjugated dibenzo[ a,c ]phenazine as additional electron-withdrawing π-spacer showed the highest efficiency of 6.54% under AM 1.5 G irradiation. It was demonstrated that the π-spacers influence the photovoltaic performance of the dithieno[3,2- f :2′,3′- h ]quinoxaline-based organic dyes significantly. The results indicated that the dyes with three π-spacers are promising candidates for efficient dye-sensitized solar cells.
研究领域:
材料科学
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能源科学
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DOI
高影响因子
ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING
·
2018
·Vol. 44
·期 1
·259-267
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IF 1.092
Yahui Zheng,Shanfa Tang,Jiaxin Wang,Mpelwa Musa,Mingzheng Pu,Tianyuan Zhou
In order to optimize the thickening performance of clean fracturing fluid, a series of sulfonate Gemini surfactants (DS m - s - m ) were synthesized and identified by FTIR, \(^{1}\hbox {HNMR}\) , and \(^{13}\hbox {CNMR}\) . The surface tension curve was obtained by testing the surface tension of the surfactant at different concentrations, and the viscosity of sulfonate Gemini surfactant solution was measured by rheometer and investigated through changing the molecular structure. The microstructures of the solution were studied by SEM. The experimental results indicated that the CMC of the surfactant decreased with increasing the length of the hydrophobic chain. Moreover, the viscosity of sulfonate Gemini surfactant changed with the carbon number (s or m) of spacer group and hydrophobic chain, and the DS18-3-18 had superior viscosity behavior. The viscosity of the DS18-3-18 solution decreased with the temperature increase but was still \(13.25 \hbox { mPa}\cdot \hbox {s}\) at \(90\,{^{\circ }}\hbox {C}\) . The microstructures of DS18- s -18 solution demonstrated that the micelles of the DS18- s -18 solution changed from spherical to layer like and finally to commixture of spherical/layer like with increasing the carbon number of spacer group ( \(s=2,3,4\) ), and the viscosity of the solution increased firstly and then decreased correspondingly. The number of sheet micelles and bulk density in DS18-3-18 solution decreased with the increase of temperature, causing the decrease of the viscosity in solution. However, the intact sheet micelles still existing in solution at \(90\,{^{\circ }}\hbox {C}\) meant that the DS18-3-18 had prominent temperature-resistant viscosity behavior. These phenomena illustrated that changing the molecular structure of surfactants could cause changes in their microstructure and finally lead to a change in the viscosity of the solution.
研究领域:
化学工程
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材料科学
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DOI
高影响因子
MOLECULES
·
2023
·Vol. 28
·期 14
·5469
·
IF 4.6
Yaqin Liang,Hui Li,Jiahui Ji,Jiayu Wang,Yujie Ji
Five ester-bonded gemini quaternary ammonium surfactants C12-En-C12(n = 2, 4, 6), with a flexible spacer group, and C12-Bm-C12(m = 1, 2), with rigid benzene spacers, were synthesized via a two-step reaction and analyzed. Furthermore, the effects of the spacer structure, spacer length and polymerization degree on the self-aggregation, antimicrobial activity and cytotoxicity of C12-En-C12and C12-Bm-C12and their corresponding monomerN-dodecyl-N,N,N-trimethyl ammonium chloride DTAC were investigated. The results showed that C12-En-C12and C12-Bm-C12had markedly lower critical micellar concentration (CMC) values and lower surface tension than DTAC. Moreover, the CMC values of C12-En-C12and C12-Bm-C12decreased with increasing spacer length. In the case of equivalent chain length, the rigidity and steric hindrance of phenylene and 1,4-benzenediyl resulted in larger CMC values for C12-Bm-C12than for C12-En-C12. The antibacterial ability of C12-En-C12and C12-Bm-C12was assessed usingEscherichia coli(E. coli) andStaphylococcus albus(S. aureus) based on minimum inhibitory concentrations (MICs). Furthermore, C12-En-C12and C12-Bm-C12exhibited higher antimicrobial activity than DTAC and had stronger function towardS. aureusthanE. coli. The antimicrobial activity was enhanced by increasing the spacer chain length and decreased with the increased rigidity of the spacers. The cytotoxic effects of C12-En-C12and C12-Bm-C12in cultured Hela cells were evaluated by the standard CCK8 method based on half-maximal inhibitory concentration (IC50). The cytotoxicity of C12-En-C12and C12-Bm-C12was significantly lower than alkanediyl-α,ω-bis(dimethyldodecylammonium) bromide surfactants and DTAC. The spacer structure and the spacer length could induce significant cytotoxic effects on Hela cells. These findings indicate that the five ester-bonded GQASs have stronger antibacterial activity and lower toxicity profile, and thus can be used in the pharmaceutical industry.Keywords:gemini surfactant;ester;antimicrobial activity;spacer;cytotoxicity
研究领域:
生物化学
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药理学
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微生物学
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DOI
PubMed
高影响因子
ADVANCED MATERIALS
·
2023
·Vol. 35
·期 16
·2211004
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IF 29.4
Benbing Shi,Xiao Pang,Bohui Lyu,Hong Wu,Jianliang Shen,Jingyuan Guan,Xiaoyao Wang,Chunyang Fan,Li Cao,Tianhao Zhu,Yan Kong,Yawei Liu,Zhongyi Jiang
Side-chain engineering of covalent organic frameworks as advanced ion conductors is a critical issue to be explored. Herein, ionic covalent organic framework membranes (iCOFMs) with spacer-engineered ionic channel are de novo designed and prepared. The ionic channels are decorated with side chains comprising spacers having different carbon chain lengths and the –SO 3 H groups at the end. Attributed to the synergistic contribution from the spacers and the –SO 3 H groups, the iCOFM with moderate-length spacer exhibit the highest through-plane proton conductivity of 889 mS cm -1 at 90 °C.
研究领域:
材料科学
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化学工程
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DOI
PubMed
高影响因子
ChemElectroChem
·
2020
·Vol. 7
·期 15
·3353-3360
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IF 4.154
Ran Zhang,Zhaoyang Wei,Weiwei Lei,Tao Jiang,Qunchao Zhang,Dean Shi
Graphical Take cover : The shielding effects of ether oxygen atoms in Poly(ethylene glycol) (PEG) molecular chains on the B atoms can be alleviated by introducing siloxane oxygens in between them (B-Si x -PEGs). The deshielding effects of siloxane spacing groups on B atoms increase along with the increase of x in the B-Si x -PEGs polymer electrolytes. Doping boron (B) atoms into poly(ethylene glycol) (PEG)-based solid polymer electrolytes (B-PEG) is believed to be an attractive method to increase the lithium-ion transference number ( ) because of the interaction between the electropositive B atoms and the anions of lithium salts. However, this effect can be largely impeded by the interaction between B and the electronegative ether oxygen atoms in the attached PEG molecular chains, which is referred to as a shielding effect. Enlarging the distance between the center B atoms and the electronegative ether oxygens is believed to be an effective way to reduce such shielding effect. In this work, different number of siloxane spacing groups (Si x ) are introduced in between the B atom and ether oxygen in the B-PEG macromolecules (B-Si x -PEGs x =0,1,3,5). As the siloxane oxygen has less electronegativity to ether oxygen, the shielding effects should be weakened and the ability of B atoms to trap the anions of lithium salt will increase. As the introduction of siloxane groups into the B-Si x -PEGs polymer electrolytes will also reduce the neat contents of both B and PEG, which has the opposite effect on the whole ionic conductivities and values, both the ionic conductivities and values of B-Si x -PEGs electrolytes first increase then decrease along with x increases from 0 to 5 when the [Li + ]:[EO] mole ratio is fixed at 1 : 10. The peak value exists at x =1. Meanwhile, both the mobilities of Li + ions (confirmed via 7 Li nuclear magnetic resonance (NMR) results) and bis(trifluoromethane) sulfonimide (TFSI − ) anions (confirmed from Raman spectra analysis) get their maximum values when x =1. However, if both the concentrations of TFSI − and B atoms in B-Si x -PEGs electrolytes are taken into consideration, the normalized diffusion coefficient of TFSI − anions obtained by molecular dynamic (MD) simulation decrease monotonically when x increases from 0 to 5. As the diffusion coefficient of TFSI − anions is determined by the interaction probability and strength of TFSI − and B atoms; these results confirm that the interaction between the B atoms and TFSI − anions increase with x . Namely, the deshielding effects of siloxane spacing groups on B atoms increase along with the increase of x in the B-Si x -PEGs polymer electrolytes, while it levels off when x exceeds 3.
研究领域:
材料科学
·
电化学
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产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2012
·Vol. 128
·期 6
·3540-3547
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IF 1.289
Hongli Yao,Xiaohui He,Lu Chen,Yiwang Chen,Defu Chen
Novel sulfonated poly(2-butoxymethylenenorbornene-co-2-(6-phenoxy-hexyloxymethylene)-5-norbornene [sP(BN/PhHN)] were prepared successfully through vinyl-addition type polymerization and then sulfonated with concentrated sulfuric acid (98%) as sulfonating agent in a component solvent. The sP(BN/PhHN)-40 with the maximal degree of sulfonation of 40% can be obtained by controlling the sulfonating reaction time from 8 to 20 h, and a proton conductivity of 3.35 × 10 −3 S/cm was achieved at 70°C. The methanol permeabilities of these membranes were in the range from 0.26 to 6.58 × 10 −7 cm 2 /s, which were remarkably lower than Nafion (2.36 × 10 −6 cm 2 /s). TEM analysis revealed that these side-chain type membranes have a microphase separated structure composed of hydrophilic side-chain domains and hydrophobic polynorbornene main chain domains. Sulfonated polynorbornene containing soft spacers displayed better properties, such as lower water uptake, high thermal properties, mechanical properties, and low methanol permeability. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
研究领域:
材料科学
·
化学工程
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DOI
高影响因子
TENSIDE SURFACTANTS DETERGENTS
·
2020
·Vol. 57
·期 1
·82-89
·
IF 1.089
Zhifei Wang,Yunling Li,Yongbo Song,Jun Li,Qinghong Zhang
A quaternary ammonium salt gemini surfactant (C 12 N) 2 O with diethyl ether as the spacer group was synthesized by dodecyl dimethyl amine and 2-chloroethyl ether. The structure of the product was confirmed by Fourier transform infrared spectra (FT-IR) and proton nuclear magnetic resonance spectra ( 1 H NMR), which showed that the structure of the synthesized product was consistent with the theoretical structure. We tested the surface tension of (C 12 N) 2 O at 25°C and found the critical micelle concentration (CMC) was roughly 2 orders of magnitude lower than that of dodecyl trimethylamine chloride (DTAC). Gemini structure and the unique diethyl ether spacer group endowed the novel amphiphile excellent properties including low contact angle and high antistatic property. (C 1 2 N) 2 O showed good compatibility with alcohol ether sulfate (AES) and dodecylbenzene sulfonate (LAS) in surfactant mixed systems. When the ratio of (C 12 N) 2 O:AES was 1:4 and (C 12 N) 2 O:LAS 1:9, the emulsifying properties were preferable to single surfactant.
研究领域:
化学
·
材料科学
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DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
·
IF 7.7
Lin Wang,Yu Pang,Meihua Xin,Mingchun Li,Lulu Shi,Yangfan Mao
In this study, three types of dodecyl chitosan quaternary ammonium salts, each with different spacer groups were synthesized. These chitosan derivatives are N′ , N′ -dimethyl- N′- dodecyl-ammonium chloride- N -amino-acetyl chitosan (DMDAC), N′- dodecyl- N -isonicotinyl chitosan chloride (DINCC) and N′ , N′ -dimethyl- N′- dodecyl-ammonium chloride- N -benzoyl chitosan (DMDBC). The synthesized products were characterized using Fourier transform infrared spectrometers, nuclear magnetic resonance, thermogravimetric analysis, and elemental analysis. The antibacterial and antibiofilm activities against Escherichia coli ( E. coli ) and Staphylococcus aureus ( S. aureus ) were investigated. The experimental results indicated that the introduction of hydrophobic groups of spacer groups could enhance the antibacterial and antibiofilm activities of the chitosan derivatives. The antibacterial rates of the chitosan derivatives were over 90 % for both E. coli and S. aureus at a concentration of 0.5 mg/mL. The chitosan derivatives removed >50 % of the mature biofilm of E. coli and over 90 % of the mature biofilm of S. aureus at a concentration of 2.5 mg/mL. Further, the synthesized chitosan derivatives were determined to be non-toxic to L929 cells. Among them, DMDBC exhibited the most promising overall performance and show potential for wide-ranging applications in food preservation, disinfectants, medical, and other fields.
研究领域:
材料科学
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生物技术
·
微生物学
·
药学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2022
·Vol. 139
·期 28
·e52614
·
IF 3.057
Quan Long,Xia Li,Yawen Huang,Qiuxia Peng,Xian Li,Liangbo Zhu,Jiajun Ma,Xu Ye,Junxiao Yang
The route via the cross-linking of hyperbranched prepolymers has potential advantage to construct low dielectric constant (low- k ) resins owing to the enhanced molecular free volume in hyperbranched structure. However, it is still a challenge to prepare hyperbranched resins with good film-forming property and low- k . In this paper, two hyperbranched polycarbosilanes with reactive benzocyclobutene groups were synthesized via hydrosilylation reaction to avoid the generation of Si O bonds for enabling the low polarity of chemical bonds. The spacing groups including phenyl or ethylene were incorporated into the hyperbranched structures, and the effect of the spacing groups on the physicochemical properties of hyperbranched polycarbosilane derived resins were investigated. The phenyl groups were found to effectively decrease the dielectric constant ( k ), while endowing the resins with good film forming ability and thermostability. The UV/thermally cured phenyl group resin owing to dual crosslinked structure, the patterns would not be deformed significantly during thermally cured process. Both hyperbranched polycarbosilane derived resins could be potential photoresists.
研究领域:
材料科学
·
高分子化学
·
电气工程
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）