Authentication email has already been sent, please check your email box: and activate it as soon as possible.
You can login to My Profile and manage your email alerts.
If you haven’t received the email, please:
|
|
There are 14 papers published in subject: > since this site started. |
Select Subject |
Select/Unselect all | For Selected Papers |
Saved Papers
Please enter a name for this paper to be shown in your personalized Saved Papers list
|
1. Analytical expressions for interaction between two palnar and sperical surface for 2-1type asymmetric electrolytes at positive surface potential | |||
LIU Guozhi | |||
Chemistry 15 March 2016 | |||
Show/Hide Abstract | Cite this paper︱Full-text: PDF (0 B) | |||
Abstract:In this paper, we suggest an analytical solution to Poisson-Boltzmann equation for the calculation of potential distributions between two identical plate colloidal particles immersed in a 2:1 type electrolyte solution with constant high or medium surface potential. Our expression fits well to the exact values of the potential between two parallel plates. Numerical results indicate that this analytical solution provides accurate description for the dimensionless distance ≤ 3. The suggested solution can be successfully applied in calculating the potential for identical plates with high or medium surface potentials. A simple analysis expression for the energy of interactions between two identical plates with constantly high or medium surface potential is given. The solutions in analytical and numerical forms become indistinguishable when , and , respectively. When , , the approximate solution is in close agreement with the numerical solution. By use of accurate analytical expression for the corresponding interaction energy between two parallel similar plates obtained presently, a simple analysis expression is given for calculating the energy of interactions between two identical spherical colloidal particles in a 2:1 type electrolyte solution with the help of Derjaguin's approximation. | |||
TO cite this article:LIU Guozhi. Analytical expressions for interaction between two palnar and sperical surface for 2-1type asymmetric electrolytes at positive surface potential[OL].[15 March 2016] http://en.paper.edu.cn/en_releasepaper/content/4680941 |
2. Confined Space Synthesis of Mesoporous Silica Nanoparticles with a Three Dimensionally Ordered Close-packing Structure | |||
WANG Jing,CHEN Huiyong | |||
Chemistry 25 December 2015 | |||
Show/Hide Abstract | Cite this paper︱Full-text: PDF (0 B) | |||
Abstract:Mesoporous silica nanoparticles with a three dimensionally ordered close-packing structure (3DOc-p MSNs) were confined synthesis through steam-assisted crystallization treatment. With perfect replication from the three dimensionally ordered mesoporous carbon template, the obtained 3DOc-p MSNs presented a unique assembly structure of colloidal crystal composed of uniform mesoporous silica spherical particles with a controllable particle size ranged from 10 to 160 nm and various mesopore morphologies of hollow, multicellar, disordered wormlike, and ordered structure with the increasing of the confined space. Moreover, sonication induced fragmentation of 10, 20, and 40 nm 3DOc-p MSNs resulted in a clear suspension of highly monodispersed mesoporous silica nanoparticles with the corresponding particle size and mesopore structure. | |||
TO cite this article:WANG Jing,CHEN Huiyong. Confined Space Synthesis of Mesoporous Silica Nanoparticles with a Three Dimensionally Ordered Close-packing Structure[J]. |
3. Influence of Hydrophobicity of Substrates on the Adsorption of Nonionic Block Copolymers | |||
SONG Junlong | |||
Chemistry 19 December 2013 | |||
Show/Hide Abstract | Cite this paper︱Full-text: PDF (0 B) | |||
Abstract:In this investigation the adsorption of nonionic polymers on model surfaces (cellulose, polypropylene, nylon and polyester) were studied using Quartz Crystal Microbalance (QCM) technique. The underlying driving force for the adsorption of nonionic lubricants onto these surfaces was discussed and our experimental observations also confirmed expected behaviors: A greater affinity of the more hydrophobic polymer species with the hydrophobic surfaces and vice versa. Hydrophobic interactions are concluded as being a predominant factor in adsorption of nonionic polymer [polyalkylene glycols (PAGs) and co-polymer of ethylene oxide and propylene oxide (Pluronic)] on textile-relevant surfaces. | |||
TO cite this article:SONG Junlong. Influence of Hydrophobicity of Substrates on the Adsorption of Nonionic Block Copolymers[OL].[19 December 2013] http://en.paper.edu.cn/en_releasepaper/content/4575038 |
4. Preparation and Characterization of Bipolar Membranes Modified by Photocatalyst Nano-ZnO and Nano-CeO2 | |||
Ting-jin Zhou,Ri-yao Chen | |||
Chemistry 06 March 2012 | |||
Show/Hide Abstract | Cite this paper︱Full-text: PDF (0 B) | |||
Abstract:Nano-ZnO-CeO2 coupled semiconductor was added into the chitosan(CS) anion exchange membrane layer to prepare the PVA-CMC/nano-ZnO-CeO2-CS (here, PVA: polyvinyl alcohol; CMC: carboxymethyl cellulose) bipolar membrane(BPM), and the prepared BPM was characterized by SEM, J-V characteristics, electronic universal testing machine, contact angle measurement and so on. Experimental results showed that nano-ZnO-CeO2 exhibited better photocatalytic property for water splitting at the interlayer of BPM than nano-ZnO or nano-CeO2, which could greatly reduce the membrane impedance of the BPM. Under the irradiation of high-pressure mercury lamps, the cell voltage of PVA-CMC/ nano-ZnO-CeO2-CS BPM decreased by 0.7V at the current density of 60mA/cm2, and the cell voltages of PVA-CMC/ nano-ZnO-CS BPM and PVA-CMC/ nano-CeO2-CS BPM were only reduced by 0.3V and 0.5V, respectively. Furthermore, the hydrophilicity, and mechanical properties of the modified BPM were increased.) | |||
TO cite this article:Ting-jin Zhou,Ri-yao Chen. Preparation and Characterization of Bipolar Membranes Modified by Photocatalyst Nano-ZnO and Nano-CeO2[J]. |
5. Preparation of Silymarin Nanosuspension by Microemulsion Dilution | |||
Zeng Hui ,Huihua Li | |||
Chemistry 14 September 2011 | |||
Show/Hide Abstract | Cite this paper︱Full-text: PDF (0 B) | |||
Abstract:Nanosuspensions of silymarin with size distribution 31-326nm were prepared though microemulsion dilution. Dynamic light scattering showed that the size of nanoparticles of silymarin changed by increasing the volume of diluted water. Transmission electron microscopy confirmed that these colloidal nanoparticles have irregular shape. This research shows that silymarin nanoparticles can be formed from microemulsion with suitable oil and surfactant. | |||
TO cite this article:Zeng Hui ,Huihua Li. Preparation of Silymarin Nanosuspension by Microemulsion Dilution[OL].[14 September 2011] http://en.paper.edu.cn/en_releasepaper/content/4442628 |
6. Interaction of BSA and long-chain imidazolium ionic liquid measured by fluorescence spectra and surface tension | |||
Fei Geng,Liqiang Zheng,Li Yu,Ganzuo Li,Chenho Tung | |||
Chemistry 23 July 2009 | |||
Show/Hide Abstract | Cite this paper︱Full-text: PDF (0 B) | |||
Abstract:The binding of long-chain imidazolium ionic liquid (IL), 1-tetradecyl-3-methylimidazolium bromide (C14mimBr) to bovine serum albumin (BSA) were investigated by fluorescence spectra and surface tension. Fluorescence spectra show that tryptophan (Trp) residues, one of the intrinsic fluorophores in BSA, are buried to a hydrophobic microenvironment with the addition of C14mimBr. The addition of C14mimBr induces denaturation of BSA. Moreover, the fluorescence quenching mechanism was determined to be static quenching. The equilibrium constant (K) and the number of binding sites (n) were calculated based on the results of fluorescence measurement. According to the surface tension plots, the critical aggregation concentration (CAC) and critical micelle concentration (CMC) under different BSA concentrations at various temperatures were investigated. The surface tension indicates that C14mimBr binds to BSA through electrostatic attraction at low concentration of C14mimBr (below CMC) and through hydrophobic interaction at high concentration of C14mimBr (above CMC). Additionally, thermodynamic parameters of micelle formation were determined. This study provides an understanding of the binding of C14mimBr to BSA. | |||
TO cite this article:Fei Geng,Liqiang Zheng,Li Yu, et al. Interaction of BSA and long-chain imidazolium ionic liquid measured by fluorescence spectra and surface tension[OL].[23 July 2009] http://en.paper.edu.cn/en_releasepaper/content/34047 |
7. Interactions between a surface active imidazolium ionic liquid and BSA | |||
Fei Geng,Liqiang Zheng,Li Yu,Jie Liu,Zhen Li | |||
Chemistry 19 February 2009 | |||
Show/Hide Abstract | Cite this paper︱Full-text: PDF (0 B) | |||
Abstract:The interactions between a surface active imidazolium ionic liquid (IL), 1-tetradecyl-3-methylimidazolium bromide (C14mimBr) and bovine serum albumin (BSA) were investigated by surface tension, isothermal titration microcalorimetry, far-UV circular dichroism (CD) and fluorescence spectra. The surface tension measurement shows the formation of C14mimBr/BSA complex and the effect of the complex on surface tension. The enthalpy change in the whole interaction process between C14mimBr and BSA was obtained by isothermal titration microcalorimetry, and the results show alteration of the BSA structure. The contents of α-helix and random coil were obtained by far-UV CD. Changes of these contents reveal that the secondary structure of BSA changes with addition of C14mimBr. Fluorescence spectra show that tryptophan (Trp) residues, one of the intrinsic fluorophores in BSA, are exposed to a hydrophobic microenvironment with the addition of C14mimBr. | |||
TO cite this article:Fei Geng,Liqiang Zheng,Li Yu, et al. Interactions between a surface active imidazolium ionic liquid and BSA[OL].[19 February 2009] http://en.paper.edu.cn/en_releasepaper/content/29320 |
8. Micelle formation of long-chain imidazolium ionic liquids in aqueous solution measured by isothermal titration microcalorimetry | |||
Fei Geng,Jie Liu,Liqiang Zheng,Li Yu,Zhen Li,Ganzuo Li,Chenho Tung | |||
Chemistry 19 February 2009 | |||
Show/Hide Abstract | Cite this paper︱Full-text: PDF (0 B) | |||
Abstract:Self-association of three long-chain imidazolium ionic liquids (ILs), C12mimBr, C14mimBr and C16mimBr in aqueous solution was studied by surface tension measurements at different temperatures. Effects of temperature and hydrocarbon chain length of the three long-chain ILs on the critical micelle concentration (CMC) were examined. Thermodynamic parameters, Gibbs free energy, enthalpy and entropy of micellization were determined by applying a mass-action model equation. Isothermal titration microcalorimetry was used to obtain the enthalpy change upon micellization of the three long-chain ILs at 25℃. Moreover, the CMCs and the thermodynamic parameters were determined based on the isothermal titration microcalorimetry results. | |||
TO cite this article:Fei Geng,Jie Liu,Liqiang Zheng, et al. Micelle formation of long-chain imidazolium ionic liquids in aqueous solution measured by isothermal titration microcalorimetry[OL].[19 February 2009] http://en.paper.edu.cn/en_releasepaper/content/29278 |
9. Stable Smectic A Liquid Crystalline Phases Formed by Zwitterionic Heterogemini Amphiphiles | |||
Tianhua Zhou,Jianxi Zhao | |||
Chemistry 04 January 2009 | |||
Show/Hide Abstract | Cite this paper︱Full-text: PDF (0 B) | |||
Abstract:A series of novel zwitterionic gemini amphiphiles with two oppositely charged ionic headgroups and two different alkyl chains within the molecule, alkylammonium-N-3-[(alkyloxy)-2-sulfate-propyl] - N, N-dimethyl (abbreviated as CmEOSACn with m, n = 8, 16; 14, 10; 10, 14 and 12, 12), has been synthesized. The thermotropic mesomorphic properties of CmEOSACn were investigated by polarizing optical microscopy, differential scanning calorimetry, and X-ray diffraction. All compounds were enantiotropic thermotropic liquid crystals and exhibited smectic A phases over a wide temperature range. The high stability of the liquid crystal phase could be attributed to the special molecular structure of the zwitterionic heterogemini amphiphiles. | |||
TO cite this article:Tianhua Zhou,Jianxi Zhao. Stable Smectic A Liquid Crystalline Phases Formed by Zwitterionic Heterogemini Amphiphiles[OL].[ 4 January 2009] http://en.paper.edu.cn/en_releasepaper/content/27275 |
10. Synthesis and Thermotropic Liquid Crystalline Properties of Heterogemini Surfactants Containing a Quaternary Ammonium and a Hydroxyl Group | |||
Tianhua Zhou,Jianxi Zhao | |||
Chemistry 04 January 2009 | |||
Show/Hide Abstract | Cite this paper︱Full-text: PDF (0 B) | |||
Abstract:A homologous series of novel heterogemini surfactants, (N, N-Dimethyl-N-[3-(alkyloxy)-2-hydroxypropyl]-alkylammonium bromide (referred to as CmOhpNCn; m, n = 10, 8; 12, 8; 14, 8; 16, 8; 14, 10; 12, 12 and 10, 14) has been synthesized. Their thermotropic phase behavior has been investigated by differential scanning calorimetry (DSC), polarizing optical microscopy (POM), infrared spectroscopy (IR) and X-ray diffraction (XRD). All the compounds showed high thermal stability and formed enantiotropic thermotropic smectic A liquid crystals. The mesophase region was sensitive to the overall length (m + n) of the two hydrophobic tails and was widened with increasing (m + n). When fixing the overall length of the two hydrophobic tails (m + n =24), the liquid crystal region was affected little by the dissymmetry of the two hydrophobic chains. The combination of IR and XRD results suggested the cis configuration of the alkyl chain and the alkoxy chain with respect to the extended N溏CH2溏CH(OH) skeleton in both crystal lattice and liquid crystal mesophase. The folding of the alkoxy chain at the carbon atom connecting the hydroxyl group led to the hydrogen bonding between the hydroxyl and the Br溏 counterion, which is beneficial to stabilizing the liquid crystal phase. | |||
TO cite this article:Tianhua Zhou,Jianxi Zhao. Synthesis and Thermotropic Liquid Crystalline Properties of Heterogemini Surfactants Containing a Quaternary Ammonium and a Hydroxyl Group[OL].[ 4 January 2009] http://en.paper.edu.cn/en_releasepaper/content/27261 |
Select/Unselect all | For Selected Papers |
Saved Papers
Please enter a name for this paper to be shown in your personalized Saved Papers list
|
About Sciencepaper Online | Privacy Policy | Terms & Conditions | Contact Us
© 2003-2012 Sciencepaper Online. unless otherwise stated