scholarly journals Fabrication of Core-Shell Magnetic Molecularly Imprinted Nanospheres towards Hypericin via Click Polymerization

Polymers ◽  
2019 ◽  
Vol 11 (2) ◽  
pp. 313 ◽  
Author(s):  
Xinxin Wang ◽  
Yuxin Pei ◽  
Yong Hou ◽  
Zhichao Pei
Keyword(s):  
Click Reaction ◽  
Average Pore Size ◽  
Core Shell ◽  
Average Pore ◽  
Molecularly Imprinted ◽  
Transfer Rates ◽  
Click Polymerization ◽  
Magnetic Nanospheres ◽  
Transmission Electron ◽  
Bet Method

The core-shell structure molecularly imprinted magnetic nanospheres towards hypericin (Fe3O4@MIPs) were prepared by mercapto-alkyne click polymerization. The shape and size of nanospheres were characterized by dynamic light scattering (DLS) and transmission electron microscope (TEM). The nanospheres were analyzed by FTIR spectroscopy to verify the thiol-yne click reaction in the presence or absence of hypericin. The Brunauer–Emmet–Teller (BET) method was used for measuring the average pore size, pore volume and surface area. The Fe3O4@MIPs synthesized displayed a good adsorption capacity (Q = 6.80 µmol·g−1). In addition, so-prepared Fe3O4@MIPs showed fast mass transfer rates and good reusability. The method established for fabrication of Fe3O4@MIPs showed excellent reproducibility and has broad potential for the fabrication of other core-shell molecularly imprinted polymers (MIPs).

The Effect of the Freeze-Thaw Cycles in Nanometer Pores on the Cement Structure

2014 ◽  
Vol 488-489 ◽  
pp. 620-624
Author(s):  
Long Zhou ◽  
Xu Liang Hou ◽  
Zhong Ping Wang
Keyword(s):  
Pore Structure ◽  
Pore Size ◽  
Average Pore Size ◽  
Pore Wall ◽  
Average Pore ◽  
Freeze Thaw ◽  
Changing Trends ◽  
Bet Method ◽  
Resistance Durability ◽  
20 Nm

The pore structure of cement-based materials is closely related to the freeze-thaw resistance durability. And this paper focused on nanometer pores to verify the connection of freeze-thaw cycles in the nanometer pores with the structure deterioration and to explore the stress in the pore wall during the freeze-thaw process. And BET method was adopted to analyze the pore structure of the cement and results indicated the changing trends of parameters such as the pore volume, average pore size and surface area of specimens. Moreover, pore size distribution presented prominent fluctuations of pore sizes in the range of 0 ~ 20 nm, while the changes on the scale of 20 ~ 100 nm were limited.

scholarly journals Photocatalytic Degradation of 2,4-Dichlorophenol by TiO2 Intercalated Talc Nanocomposite

2019 ◽  
Vol 2019 ◽  
pp. 1-11 ◽  
Author(s):  
Manqing Ai ◽  
Wenli Qin ◽  
Tian Xia ◽  
Ying Ye ◽  
Xuegang Chen ◽  
...  
Keyword(s):  
Energy Dispersive Spectrometer ◽  
Photon Absorption ◽  
Order Kinetic ◽  
X Ray Diffraction ◽  
Average Pore ◽  
Thermogravimetric Analyzer ◽  
Surface Areas ◽  
Transmission Electron ◽  
Strong Adsorption ◽  
Bet Method

Novel nanocomposites have been prepared by intercalating TiO2 nanoparticles into talc. The nanocomposites have been verified by X-ray diffraction (XRD) from the appearance of a characteristic diffraction peak of TiO2. Thermal behavior of the prepared samples is examined by thermogravimetric analyzer (TGA), scanning electron microscope (SEM), and energy dispersive spectrometer (EDS), which have shown no TiO2 particles on the surface of the talc. The TiO2 particles are found in the layers of talc by transmission electron microscopy (TEM) and the Brunauer-Emmett-Teller (BET) method, which have shown the increase of specific surface areas and total pore volumes and the decline of average pore diameters. As the strong adsorption ability of talc can intensify the power of photon absorption and capture-recombination carriers, more than 99.5% of 2,4-dichlorophenol can be degraded in 1 h by the nanocomposite under an ultraviolet lamp in neutral solution and room temperature after reaching adsorption equilibrium, and the result of adsorbance is in accord with the first-order kinetic. The degradation rate was maintained at about 99% after 20 times. Therefore, the prepared talc/TiO2 nanocomposite is an efficient, stable, and recyclable material for wastewater treatment.

Synthesis of Anatase/Brookite Mixtured TiO2 Nanoparticles by a Chimie Douce Technique

2013 ◽  
Vol 734-737 ◽  
pp. 2528-2531
Author(s):  
Yu Mei Gong ◽  
Qing Liang ◽  
Jing Guo ◽  
Hong Zhang ◽  
Fu Cheng Guan
Keyword(s):  
Electron Microscope ◽  
Anatase Phase ◽  
Spherical Shape ◽  
Nitrogen Adsorption ◽  
X Ray Diffraction ◽  
Average Pore ◽  
Specific Pore Volume ◽  
Transmission Electron ◽  
Bet Method ◽  
Ft Ir

Anatase/brookite mixtured TiO2nanoparticles have been synthesized by using a two-step process through a chimie douce technique. The as-prepared powders were characterized by Fourier transform infrared (FT-IR) spectra, X-ray diffraction (XRD), transmission electron microscope (TEM), scanning electron microscope (SEM), and a nitrogen adsorption apparatus in multipoint Brunauer-Emmett-Teller (BET) method. The results indicated that the TiO2nanoparticles were composed of biphasial anatase/brookite mixtures, 38% anatase phase formed in quasi-spherical shape and 62% brookite phase formed in nanorod shape. The specific surface area, the average pore diameter, and the specific pore volume were 100.06 m2/g, 14.0 nm, and 0.561 cm3/g, respectively.

scholarly journals Preparation and characterization of polyaniline-silica composite material

2012 ◽  
Vol 47 (3) ◽  
pp. 249-256 ◽  
Author(s):  
US Akhter ◽  
MS Miran ◽  
MABH Susan ◽  
MYA Mollah ◽  
MM Rahman
Keyword(s):  
Composite Material ◽  
Average Pore Size ◽  
Chemical Properties ◽  
Bet Surface Area ◽  
Average Pore ◽  
Enthalpy Of Adsorption ◽  
Silica Composite ◽  
Transmission Electron ◽  
The Individual ◽  
Individual Hydrocarbons

Polyaniline-silica (PAni-silica) composite material with 40% silica was prepared by polymerization of aniline in a medium consisting of colloidal silica, freshly prepared by hydrolysis of sodium silicate at room temperature at pH 6.5. The physico-chemical properties of both PAni and the composite material, PAni-silica were studied by FT-IR and transmission electron microscopy and measurements of Brunauer- Emmett-Teller (BET) isotherms. PAni-silica composites showed inhomogeneous pore distribution, although PAni has no significant pores. Average pore size of PAni-silica was 280 and 175 Å during adsorption and desorption of nitrogen, respectively. The interactions of PAnisilica composite and PAni with saturated hydrocarbons were investigated by inverse gas chromatography. The composite material was found to be efficient for separation of a mixture of hydrocarbons, in the range of C5-C9, owing to large BET surface area. Enthalpy of adsorption of the individual hydrocarbons was evaluated from an analysis of the retention time and the flow rate of the carrier gas. For PAni, the enthalpy of adsorption was very low; however, the value for the composite material was found to be comparable to the enthalpy of evaporation of the individual hydrocarbons. DOI: http://dx.doi.org/10.3329/bjsir.v47i3.13055 Bangladesh J. Sci. Ind. Res. 47(3), 249-256, 2012

Preparation and Structural Characterization of SiO2-ZrO2 Aerogels

2007 ◽  
Vol 336-338 ◽  
pp. 2282-2285
Author(s):  
Xiao Dong He ◽  
He Xin Zhang ◽  
Yao Li ◽  
Chang Qing Hong ◽  
Jiu Peng Zhao
Keyword(s):  
Average Pore Size ◽  
Supercritical Drying ◽  
X Ray Diffraction ◽  
Average Pore ◽  
Surface Areas ◽  
Fourier Transformed Infrared Spectroscopy ◽  
Transmission Electron ◽  
Ft Ir ◽  
Chemical Conditions

Low density SiO2-xZrO2 aerogels with x=35wt%, 65wt%, 75wt%, 90wt%, 95wt% were prepared by CO2 supercritical drying technique with tetraethylorthosilicate (TEOS) and zirconyl nitrate dihydrate (ZrO(NO3)2 .2H2O) by hydrolytic polycondensation under different chemical conditions. The prepared aerogels are performed by X-ray Diffraction (XRD), Transmission electron microscopy (TEM), Fourier transformed infrared spectroscopy (FT-IR) and BET surface areas to characterize and analyze the morphology and pore structure of SiO2-ZrO2 aerogels. The results showed that the SiO2-ZrO2 areogels are the typical of nano mesopores and the average pore size is about 50 nm. The specific surface areas varied from 345.5 to 615.5 m2/g with (SBET)MAX = 615.5 m2/g with 20wt% Zirconia; Moreover a mass of Si-O-Zr bands formed in the aerogels and the formation mechanism of Si-O-Zr bands are also discussed.

Synthesis and Characterization of Bridged Amine-Functionalized Mesoporous Organosilica Materials

2013 ◽  
Vol 652-654 ◽  
pp. 799-814
Author(s):  
Qing He Zhang ◽  
Dong Lian ◽  
Xiu Qing Li ◽  
Hong Tao
Keyword(s):  
Average Pore Size ◽  
Mas Nmr ◽  
X Ray Diffraction ◽  
Average Pore ◽  
Amine Functionalized ◽  
Mesoporous Organosilica ◽  
Transmission Electron ◽  
Analytical Potential ◽  
Ordered Mesoporous ◽  
Organosilica Materials

The periodic bridged amine-functionalized mesoporous organosilica (BAFMOs) was synthesized by condensation of bridged silicon precursor 1,2-Bis(triethoxysilyl)-ethane (BTESE) and Bis(3-(methylamino)propyl)-trimethoxysilane (BTMSPMA) under acidic conditions with the aid of NaCl and ethanol. A triblock copolymer P123 was used as template. X-ray diffraction and transmission electron microscopy revealed that the resultant BAFMOs materials possess ordered mesoporous. N2sorption showed that the specific surface area gradual decreased, from 970m2/g to 795m2/g, whereas the average pore size increased, from 3.7 nm to 5.4 nm as the amount of BTMSPMA increased.13C CP MAS NMR and29Si MAS NMR confirmed the retaining of the Si-C as well as the existing of the amino in the silica skeleton. The analytical potential of the materials is demonstrated with separation of isomeric molecules in reverse phase chromatography mode compared with commercial C18 column.

Preferential catalytic ozonation of p-nitrophenol by molecularly imprinted Fe3O4/SiO2 core-shell magnetic composites

2013 ◽  
Vol 69 (1) ◽  
pp. 170-176 ◽  
Author(s):  
Jiannan Yang ◽  
Shuzhen Li ◽  
Yibin Gong ◽  
Chun He ◽  
Qiong Zhang ◽  
...  
Keyword(s):  
Catalytic Ozonation ◽  
Core Shell ◽  
X Ray Diffraction ◽  
Competitive Reaction ◽  
Magnetic Composites ◽  
Molecularly Imprinted ◽  
Transmission Electron ◽  
Strong Adsorption ◽  
Recognition Ability ◽  
Shell Particles

Molecularly imprinted Fe3O4/SiO2 core-shell magnetic composites (Fe3O4/SiO2-MIP) were successfully prepared via anchoring p-nitrophenol (p-NP) imprinted functional polymers on the surface of amino-modified Fe3O4/SiO2 core-shell particles. Synthesized magnetic Fe3O4/SiO2-MIP composites were characterized by X-ray diffraction, scanning electronic microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, and magnetic property measurement. The preferential catalytic ozonation of p-nitrophenol was evaluated in comparison with the competitive reaction in the presence of coexistent phenol. The results showed that the prepared Fe3O4/SiO2-MIP composites exhibit strong adsorption ability due to the strong bonding between p-NP and the molecularly imprinted layer. The Fe3O4/SiO2-MIP demonstrated a preferential catalytic ozonation of p-NP by the recognition ability of the molecularly imprinted layer to the target p-NP. The enhanced catalytic activity using Fe3O4/SiO2-MIP composites could be attributed to the excellent recognition absorption of the MIP layer on the surface of Fe3O4/SiO2-MIP to p-NP.

scholarly journals A modest method of synthesis Cu- based metal-organic frameworks using benzene dicarbocxylate as a ligan for promising candidate of flue gas CO2 adsorption

2021 ◽  
Vol 21 (3) ◽  
pp. 128-134
Author(s):  
MUTTAQIN MUTTAQIN ◽  
FARID IMAM HIDAYAT
Keyword(s):  
Metal Organic Framework ◽  
Average Pore Size ◽  
Metal Organic Frameworks ◽  
Font Size ◽  
Average Pore ◽  
Good Thermal Stability ◽  
Surface Areas ◽  
Small Pore ◽  
Bet Method ◽  
Metal Organic

Metal organic framework (MOF) is one of extraordinary materials in many technical field applications. One of them is as CO2 gas adsorbent. We studied, synthesized, and characterized Copper-based material, known as Metal organic frameworks (MOFs), using a solvothermal-based modification method. Copper salt (Cu (NO3)2. 3H2O) and benzene dicarboxylic acid (H2BDC) were mixed and then heated in an oven at 120°C, to produce low impurities, small pore and uniform particle size of materials called CuBDC. Infrared spectroscopy and XRD data confirmed the formation of CuBDC. Furthermore, the result showed that CuBDC frameworks have good thermal stability up to 330°C.  Thereafter SEM picture showed random, layered, and asymmetrical corners structure which is typical of triclinic crystal system. Lastly, specific surface areas and the porosity were analyzed using The Brunauer-Emmett-Teller (BET) method. It recorded 485 m2.g-1 of surface area while average pore volume and average pore size are 0.16 cm3.g-1 and 5.9 Å respectively.   @font-face {font-family:"Cambria Math"; panose-1:2 4 5 3 5 4 6 3 2 4; mso-font-charset:0; mso-generic-font-family:roman; mso-font-pitch:variable; mso-font-signature:-536869121 1107305727 33554432 0 415 0;}p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-unhide:no; mso-style-qformat:yes; mso-style-parent:""; margin:0cm; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman",serif; mso-fareast-font-family:"Times New Roman"; mso-ansi-language:EN-US;}.MsoChpDefault {mso-style-type:export-only; mso-default-props:yes; font-size:10.0pt; mso-ansi-font-size:10.0pt; mso-bidi-font-size:10.0pt; mso-ansi-language:IN; mso-fareast-language:IN;}div.WordSection1 {page:WordSection1;}

scholarly journals Development of hollow δ-FeOOH structures for mercury removal from water

2021 ◽  
Author(s):  
Luiz F. O. Maia ◽  
Guilherme Lages ◽  
Patricia C. C. Ladeira ◽  
Bruno Lemos Batista ◽  
Márcia C. S. Faria ◽  
...  
Keyword(s):  
Average Pore Size ◽  
Active Surface ◽  
Metal Species ◽  
Point Of Zero Charge ◽  
Average Pore ◽  
Oh Groups ◽  
Transmission Electron ◽  
Naoh Solution ◽  
Active Surface Sites ◽  
20 Nm

Abstract δ-FeOOH, a magnetic iron oxyhydroxide, has a significant number of -OH groups on its surface. These provide an attractive platform for heavy metal species in contaminated water, giving it potential as an adsorbent. Its performance can be improved by increasing the number of active surface sites. δ-FeOOH hollow structures were synthesized on a mesoporous silica surface then treated with NaOH solution. X-ray diffraction (XRD) and transmission electron microscopy (TEM) confirmed that structure synthesis was successful. δ-FeOOH, 5,27 nm, hollow crystals were produced with 63 m2 g−1 surface area and 20 nm average pore size. The point of zero charge was 4.72, which is beneficial for Hg(II) adsorption near neutral pH. The maximum Hg(II) adsorption capacity at pH 7 was determined as 89.1 mg g−1. The kinetics data were best fitted by a pseudo-second-order model with k2 equal 0,1151 g mg−1min−1. Finally, a nanomaterial filter was developed and used to remove mercury in water samples from a Brazilian river.

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