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2013 Volume 24 Issue 2
2013, 24(2): 89-92
Abstract:
This paper reviews the progress of two-dimensional mesoporous materials including their synthesis strategy, mesostructure, composition, surface property, flexibility, and potential applications. During the past two decades, research on two-dimensional mesoporous materials has experienced an evolution from fragile coatings to flexible membranes. Aiming at practical applications, it is significant to support mesoporous materials with proper matrices for example porous membranes especially flexible ones to form mesoporous composite membranes with designed pore size and chemistry.
This paper reviews the progress of two-dimensional mesoporous materials including their synthesis strategy, mesostructure, composition, surface property, flexibility, and potential applications. During the past two decades, research on two-dimensional mesoporous materials has experienced an evolution from fragile coatings to flexible membranes. Aiming at practical applications, it is significant to support mesoporous materials with proper matrices for example porous membranes especially flexible ones to form mesoporous composite membranes with designed pore size and chemistry.
2013, 24(2): 93-95
Abstract:
Optical hybrid materials based on inorganic hosts and organic sensitizer guests hold promise for a virtually unlimited number of applications. In particular, the interaction and the combination of the properties of a defined inorganic matrix and a specific sensitizer could lead to synergistic effects in luminescence enhancing and tuning. The current article focuses on the intercalation assembly of optical hybrid materials based on the layered terbium hydroxide (LTbH) hosts and organic divalent carboxylic sensitizer anion guests by a hydrothermal process. The studies on the interactions between hosts and guests indicate that the type and arrangement of organic guests in the layer spacing of the LTbH hosts can make a difference in the luminescence of the hybrid inorganic-organic materials.
Optical hybrid materials based on inorganic hosts and organic sensitizer guests hold promise for a virtually unlimited number of applications. In particular, the interaction and the combination of the properties of a defined inorganic matrix and a specific sensitizer could lead to synergistic effects in luminescence enhancing and tuning. The current article focuses on the intercalation assembly of optical hybrid materials based on the layered terbium hydroxide (LTbH) hosts and organic divalent carboxylic sensitizer anion guests by a hydrothermal process. The studies on the interactions between hosts and guests indicate that the type and arrangement of organic guests in the layer spacing of the LTbH hosts can make a difference in the luminescence of the hybrid inorganic-organic materials.
2013, 24(2): 96-98
Abstract:
A new colorimetric and fluorescent probe, 2-(2,4-dinitrostyryl)-1,3,3-trimethyl-3H-indolium iodide (DTI), for selective and sensitive detection of biological thiols is reported. In aqueous solution at physiological pH 7.4, biological thiols react with DTI via Michael addition to give the brownish red adduct concomitant with fluorescence emission decrease.
A new colorimetric and fluorescent probe, 2-(2,4-dinitrostyryl)-1,3,3-trimethyl-3H-indolium iodide (DTI), for selective and sensitive detection of biological thiols is reported. In aqueous solution at physiological pH 7.4, biological thiols react with DTI via Michael addition to give the brownish red adduct concomitant with fluorescence emission decrease.
2013, 24(2): 99-102
Abstract:
A facile method for the shape-selective synthesis of silica nanostructures using a reversemicroemulsion-mediated template (RMMT) technique is reported. In this method, positive poly-Llysine (PLL) is selected as template due to its configuration diversity. By adjusting pH and concentration, PLL demonstrates various secondary structures containing random coil, α-helix and β-sheet, which result in the formation of silica nanorods, silica nanospheres and silica nanotubes in the reversemicroemulsion system, respectively. Thus, the shape-selective synthesis of silica nanostructures might be achieved by using PLL as structural template in the reverse-microemulsion system.
A facile method for the shape-selective synthesis of silica nanostructures using a reversemicroemulsion-mediated template (RMMT) technique is reported. In this method, positive poly-Llysine (PLL) is selected as template due to its configuration diversity. By adjusting pH and concentration, PLL demonstrates various secondary structures containing random coil, α-helix and β-sheet, which result in the formation of silica nanorods, silica nanospheres and silica nanotubes in the reversemicroemulsion system, respectively. Thus, the shape-selective synthesis of silica nanostructures might be achieved by using PLL as structural template in the reverse-microemulsion system.
2013, 24(2): 103-106
Abstract:
Graphitic carbon nitride (g-C3N4) was synthesized via direct pyrolysis of melamine and its electrocatalysis toward oxygen reduction reaction was studied. The morphology and structures of the products were characterized by scanning electron microscope and X-ray powder diffractometer. It was found that higher pyrolysis temperature resulted in more perfect crystalline structure of the graphitic carbon nitride product. Electrochemical characterizations show that the g-C3N4 has electrocatalytic activity toward ORR through a two-step and two-electron process.
Graphitic carbon nitride (g-C3N4) was synthesized via direct pyrolysis of melamine and its electrocatalysis toward oxygen reduction reaction was studied. The morphology and structures of the products were characterized by scanning electron microscope and X-ray powder diffractometer. It was found that higher pyrolysis temperature resulted in more perfect crystalline structure of the graphitic carbon nitride product. Electrochemical characterizations show that the g-C3N4 has electrocatalytic activity toward ORR through a two-step and two-electron process.
2013, 24(2): 107-110
Abstract:
The interactions between small molecules and proteins constitute a critical regulatory mechanism in many fundamental biological processes. A novel biosensing strategy has been developed for sensitive and selective detection of small molecule and protein interaction on the basis of terminal protection of small molecule-linked ssDNA-SWNT nanoassembly. The developed strategy is demonstrated using folate and its binding protein folate receptor (FR) as a model case. The results reveal the developed technique displays superb resistance to non-specific binding, very low detection limit as low as subnanomolar, and a wide dynamic range from 100 pmol/L to 500 nmol/L of FR. Thus, it may offer a simple, cost-effective, highly selective and sensitive platform for homogeneous fluorescence detection of small molecule-protein interaction and related biochemical studies.
The interactions between small molecules and proteins constitute a critical regulatory mechanism in many fundamental biological processes. A novel biosensing strategy has been developed for sensitive and selective detection of small molecule and protein interaction on the basis of terminal protection of small molecule-linked ssDNA-SWNT nanoassembly. The developed strategy is demonstrated using folate and its binding protein folate receptor (FR) as a model case. The results reveal the developed technique displays superb resistance to non-specific binding, very low detection limit as low as subnanomolar, and a wide dynamic range from 100 pmol/L to 500 nmol/L of FR. Thus, it may offer a simple, cost-effective, highly selective and sensitive platform for homogeneous fluorescence detection of small molecule-protein interaction and related biochemical studies.
2013, 24(2): 111-113
Abstract:
Two new guaianolide-type sesquiterpenoids, 4β,9β-dihydroxy-1α,5α-H-guaia-6,10(14)-dien (1) and 4β,9β,10α-trihydroxy-1α,5α-H-guaia-6-en (2), along with four known sesquiterpenoids (3a, 3b, 4 and 5), were isolated from Kadsura interior. Their structures and configurations were elucidated by spectroscopicmethods including 2D-NMR and HR-MS techniques. Compounds 3a and 3b were obtained as a pair of enantiomers, and their structure and absolute configuration were established from their extensive NMR spectra and by single-crystal X-ray analysis.
Two new guaianolide-type sesquiterpenoids, 4β,9β-dihydroxy-1α,5α-H-guaia-6,10(14)-dien (1) and 4β,9β,10α-trihydroxy-1α,5α-H-guaia-6-en (2), along with four known sesquiterpenoids (3a, 3b, 4 and 5), were isolated from Kadsura interior. Their structures and configurations were elucidated by spectroscopicmethods including 2D-NMR and HR-MS techniques. Compounds 3a and 3b were obtained as a pair of enantiomers, and their structure and absolute configuration were established from their extensive NMR spectra and by single-crystal X-ray analysis.
2013, 24(2): 114-116
Abstract:
One new pyrrole alkaloid, N-(2E)-3-(3,4-dihydrophenyl)prop-N1'-(4-aminobutyl)-3-pyrrole formaldehyde (1), was isolated from the whole herbs of Selaginella moellendorfii Hieron. The structure was elucidated by spectroscopic analyses including UV, IR, 1D NMR, 2D NMR and MS methods. Additionally, compound 1 exhibited potent protective effect against the injury of human umbilical vein endothelial cell (HUVECs) induced by high concentrations of glucose in vitro.
One new pyrrole alkaloid, N-(2E)-3-(3,4-dihydrophenyl)prop-N1'-(4-aminobutyl)-3-pyrrole formaldehyde (1), was isolated from the whole herbs of Selaginella moellendorfii Hieron. The structure was elucidated by spectroscopic analyses including UV, IR, 1D NMR, 2D NMR and MS methods. Additionally, compound 1 exhibited potent protective effect against the injury of human umbilical vein endothelial cell (HUVECs) induced by high concentrations of glucose in vitro.
2013, 24(2): 117-119
Abstract:
L-Ascorbic acid (AA, vitamin C) exhibits a high concentration in the brain. The transportation of AA in brain is mainly mediated by the glucose transporter 1 (GLUT1) and the Na+-dependent vitamin C transporter SVCT2. While L-ascorbic acid C6-O conjugation has been investigated as a tool to enhance brain drug delivery, C5-O conjugation and C5-O & C6-O conjugation as brain targeting tools have not been reported. In this letter, ibuprofen was linked directly to C5-O, C6-O and C5-O & C6-O positions of Lascorbic acid with eater bonds, providing prodrug 1, 2 and 3, respectively, to improve their targeting abilities in the brain. Prodrug 1, 2 and 3 were synthesized in facile ways with good yields. And the preliminary evaluation in vivo illustrated that prodrug 2 had a better targeting ability than prodrug 1. Moreover, prodrug 3, whose C5-O & C6-O positions were both modified, had good targeting ability for brain which will provide an important evidence for our further study on C5-O-& C6-O-di-derivatives of L-ascorbic acid.
L-Ascorbic acid (AA, vitamin C) exhibits a high concentration in the brain. The transportation of AA in brain is mainly mediated by the glucose transporter 1 (GLUT1) and the Na+-dependent vitamin C transporter SVCT2. While L-ascorbic acid C6-O conjugation has been investigated as a tool to enhance brain drug delivery, C5-O conjugation and C5-O & C6-O conjugation as brain targeting tools have not been reported. In this letter, ibuprofen was linked directly to C5-O, C6-O and C5-O & C6-O positions of Lascorbic acid with eater bonds, providing prodrug 1, 2 and 3, respectively, to improve their targeting abilities in the brain. Prodrug 1, 2 and 3 were synthesized in facile ways with good yields. And the preliminary evaluation in vivo illustrated that prodrug 2 had a better targeting ability than prodrug 1. Moreover, prodrug 3, whose C5-O & C6-O positions were both modified, had good targeting ability for brain which will provide an important evidence for our further study on C5-O-& C6-O-di-derivatives of L-ascorbic acid.
2013, 24(2): 120-122
Abstract:
A group of 3-amino-2-pyrones were synthesized and their biological activities were evaluated for inhibiting cyclooxygenase (COX) activity. This study has led to the identification of COX-1-selective inhibitors. Among the tested compounds, the compound 5j exhibited the most potent COX-1 inhibitory activity (IC50 = 19.32 mg/mL) and COX-1 selectivity index (SI = 41.98).
A group of 3-amino-2-pyrones were synthesized and their biological activities were evaluated for inhibiting cyclooxygenase (COX) activity. This study has led to the identification of COX-1-selective inhibitors. Among the tested compounds, the compound 5j exhibited the most potent COX-1 inhibitory activity (IC50 = 19.32 mg/mL) and COX-1 selectivity index (SI = 41.98).
2013, 24(2): 123-126
Abstract:
A new series of pyrido[1,2-a]benzimidazole derivatives bearing the aryloxypyrazole nucleus have been synthesized by base-catalyzed cyclocondensation reaction through multi-component reaction (MCR) approach. All the synthesized compounds were investigated against a representative panel of pathogenic strains using broth microdilution minimum inhibitory concentration (MIC) method for their in vitro antimicrobial activity. Reviewing the data, majority of the compounds were found to be active against employed pathogens. SAR study explores that antimicrobial activity is strongly depends on the nature of the substituents at the ether linked aryl ring attached to the pyrazole unit, together with the substituent present on the C5 of the benzimidazole unit.
A new series of pyrido[1,2-a]benzimidazole derivatives bearing the aryloxypyrazole nucleus have been synthesized by base-catalyzed cyclocondensation reaction through multi-component reaction (MCR) approach. All the synthesized compounds were investigated against a representative panel of pathogenic strains using broth microdilution minimum inhibitory concentration (MIC) method for their in vitro antimicrobial activity. Reviewing the data, majority of the compounds were found to be active against employed pathogens. SAR study explores that antimicrobial activity is strongly depends on the nature of the substituents at the ether linked aryl ring attached to the pyrazole unit, together with the substituent present on the C5 of the benzimidazole unit.
2013, 24(2): 127-130
Abstract:
A series of novel 3-[5-(1H-indol-3-yl-methyl)-2-oxo-[1,3,4]oxadiazol-3-yl]propionitrile (5), 3-[4-amino-3-(1H-indol-3-yl-methyl)-5-oxo-4,5-dihydro-[1,2,4]triazol-1-yl]propionitrile (6), 3-[5-(1H-indol-3-yl-methyl)-2-thioxo-[1,3,4]oxadiazol-3-yl]propionitrile (7) and 3-[4-amino-3-(1H-indol-3-ylmethyl)-5-thioxo-4,5-dihydro-[1,2,4]triazol-1-yl]propionitrile (8) were synthesized in good yields from the intermediate (1H-indol-3-yl)-acetic acid N'-(2-cyanoethyl)hydrazide (4). The chemical structures of the newly synthesized compounds were elucidated by their IR, 1H NMR and MS. Further, all the compounds were screened for their antimicrobial activity against Gram-positive, Gram-negative bacteria and also tested their ability toward anti-inflammatory activity.
A series of novel 3-[5-(1H-indol-3-yl-methyl)-2-oxo-[1,3,4]oxadiazol-3-yl]propionitrile (5), 3-[4-amino-3-(1H-indol-3-yl-methyl)-5-oxo-4,5-dihydro-[1,2,4]triazol-1-yl]propionitrile (6), 3-[5-(1H-indol-3-yl-methyl)-2-thioxo-[1,3,4]oxadiazol-3-yl]propionitrile (7) and 3-[4-amino-3-(1H-indol-3-ylmethyl)-5-thioxo-4,5-dihydro-[1,2,4]triazol-1-yl]propionitrile (8) were synthesized in good yields from the intermediate (1H-indol-3-yl)-acetic acid N'-(2-cyanoethyl)hydrazide (4). The chemical structures of the newly synthesized compounds were elucidated by their IR, 1H NMR and MS. Further, all the compounds were screened for their antimicrobial activity against Gram-positive, Gram-negative bacteria and also tested their ability toward anti-inflammatory activity.
2013, 24(2): 131-133
Abstract:
A convenient approach for the preparation of (1S,3'R,4'S,5'S,6'R)-5-chloro-6-[(4-ethylphenyl)methyl]-3',4',5',6'-tetrahydro-6'-(hydroxymethyl)-spiro[isobenzofuran-1(3H), 2'-[2H]pyran]-3',4',5'-triol is developed. The targeted compound was synthesized from 2-bromo-4-methylbenzoic acid in nine steps and the isomers of undesired ortho-products were avoided during the preparation.
A convenient approach for the preparation of (1S,3'R,4'S,5'S,6'R)-5-chloro-6-[(4-ethylphenyl)methyl]-3',4',5',6'-tetrahydro-6'-(hydroxymethyl)-spiro[isobenzofuran-1(3H), 2'-[2H]pyran]-3',4',5'-triol is developed. The targeted compound was synthesized from 2-bromo-4-methylbenzoic acid in nine steps and the isomers of undesired ortho-products were avoided during the preparation.
2013, 24(2): 134-136
Abstract:
Synthesis of isoxazolyl-1H-2,3-pyrrole dicarboxylate (4) was simply achieved by one-pot three component reaction of isoxazole amine (1) with diethyl acetylenedicarboxylate (DEAD) (2), and glyoxal (3), in acetonitrile catalyzed by diazabicyclo octane (DABCO).
Synthesis of isoxazolyl-1H-2,3-pyrrole dicarboxylate (4) was simply achieved by one-pot three component reaction of isoxazole amine (1) with diethyl acetylenedicarboxylate (DEAD) (2), and glyoxal (3), in acetonitrile catalyzed by diazabicyclo octane (DABCO).
2013, 24(2): 137-139
Abstract:
A novel DABCO-catalyzed Ireland-Claisen rearrangement/Diels-Alder tandem reaction of propargylic acrylates 3 with dienophiles 4 was developed in the presence of an excess TMSCl and DBU with 1% hydroquinone as polymerization inhibitor in acetonitrile at refluxing temperature under air. This protocol gave cyclic a,b-unsaturated carboxylic acids 5 with complete regioselectivity.
A novel DABCO-catalyzed Ireland-Claisen rearrangement/Diels-Alder tandem reaction of propargylic acrylates 3 with dienophiles 4 was developed in the presence of an excess TMSCl and DBU with 1% hydroquinone as polymerization inhibitor in acetonitrile at refluxing temperature under air. This protocol gave cyclic a,b-unsaturated carboxylic acids 5 with complete regioselectivity.
2013, 24(2): 140-142
Abstract:
An efficient and convenient procedure of the synthesis of 1,1-diacetates from aromatic aldehydes and acetic anhydride under mild and solvent-free conditions at room temperature, in the presence of PEG-SO3H is reported. PEG-SO3H acts as a catalyst and can be recovered and reused eight times without apparent loss of its catalytic activity.
An efficient and convenient procedure of the synthesis of 1,1-diacetates from aromatic aldehydes and acetic anhydride under mild and solvent-free conditions at room temperature, in the presence of PEG-SO3H is reported. PEG-SO3H acts as a catalyst and can be recovered and reused eight times without apparent loss of its catalytic activity.
2013, 24(2): 143-144
Abstract:
A simple and one-pot method for the synthesis of octahydroquinazolinone is reported. Cu/SiO2 in refluxing ethanol catalyzes this three-component condensation reaction to afford the corresponding quinazolinones in good yields.
A simple and one-pot method for the synthesis of octahydroquinazolinone is reported. Cu/SiO2 in refluxing ethanol catalyzes this three-component condensation reaction to afford the corresponding quinazolinones in good yields.
2013, 24(2): 145-148
Abstract:
Based on design and synthesis of salicylideneaniline derivatives (1a-1d), we demonstrate a prototypical system to investigate the excited-state intramolecular charge transfer (ESICT) coupled excited-state intramolecular proton transfer (ESIPT) reaction via the dipolar functionality of the molecular framework. In solid and aprotic solvents 1a-1d exist mainly as E conformers that possess an intramolecular sixmembered-ring hydrogen bond. Compounds 1a-1c exhibit a unique proton-transfer tautomer emission, while compound 1d exhibits remarkable dual emission due to the different solvent-polarity environment between ESICT and ESIPT states. Time-dependent density functional theory (TDDFT) calculations are reported on these Schiff bases in order to rationalize their electronic structure and absorption spectra.
Based on design and synthesis of salicylideneaniline derivatives (1a-1d), we demonstrate a prototypical system to investigate the excited-state intramolecular charge transfer (ESICT) coupled excited-state intramolecular proton transfer (ESIPT) reaction via the dipolar functionality of the molecular framework. In solid and aprotic solvents 1a-1d exist mainly as E conformers that possess an intramolecular sixmembered-ring hydrogen bond. Compounds 1a-1c exhibit a unique proton-transfer tautomer emission, while compound 1d exhibits remarkable dual emission due to the different solvent-polarity environment between ESICT and ESIPT states. Time-dependent density functional theory (TDDFT) calculations are reported on these Schiff bases in order to rationalize their electronic structure and absorption spectra.
2013, 24(2): 149-152
Abstract:
A novel benzodithiophene-containing organic dye BDT was synthesized and characterized as a sensitizer for a nanocrystalline TiO2-based dye-sensitized solar cell. The BDT dye shows two major electronic absorptions. The absorption of the BDT dye covers a broad visible range from 300 nm to 550 nm. The benzodithiophene unit was used as a π bridge with several advantages: (1) It facilitates the electron transfer from the donor to the acceptor; (2) A facile structural modification on the 4,8-positions in the benzodithiophene unit can be achieved; (3) Fusing benzene with two flanking thiophene units improves the thermal stability. Under simulated AM1.5G solar light (100 mW/cm2) illumination, the DSC based on BDT gives a power conversion efficiency of 1.78%.
A novel benzodithiophene-containing organic dye BDT was synthesized and characterized as a sensitizer for a nanocrystalline TiO2-based dye-sensitized solar cell. The BDT dye shows two major electronic absorptions. The absorption of the BDT dye covers a broad visible range from 300 nm to 550 nm. The benzodithiophene unit was used as a π bridge with several advantages: (1) It facilitates the electron transfer from the donor to the acceptor; (2) A facile structural modification on the 4,8-positions in the benzodithiophene unit can be achieved; (3) Fusing benzene with two flanking thiophene units improves the thermal stability. Under simulated AM1.5G solar light (100 mW/cm2) illumination, the DSC based on BDT gives a power conversion efficiency of 1.78%.
2013, 24(2): 153-155
Abstract:
A novel water-soluble macromolecular light stabilizer was synthesized by grafting 2-chloro-4,6-bis-[(2,2,6,6-tetramethylpiperidin-4-yl)amino]-1,3,5-triazine onto polyvinylamine. The intermediate 2-chloro-4,6-bis-[(2,2,6,6-tetramethylpiperidin-4-yl)amino]-1,3,5-triazine and the obtained macromolecular light stabilizer were characterized by 1H NMR, HRMS, IR and UV spectroscopy. Cotton fabrics dyed with C.I. Reactive Yellow 145, C.I. Reactive Red 195 and C.I. Reactive Blue 19 were finished with the macromolecular light stabilizer, and the lightfastness of the dyes was tested. The results showed that the lightfastness of the reactive dyes was improved by 0.5-1.0 grade after being finished and the macromolecular light stabilizer exhibited good wash fastness and thermal stability.
A novel water-soluble macromolecular light stabilizer was synthesized by grafting 2-chloro-4,6-bis-[(2,2,6,6-tetramethylpiperidin-4-yl)amino]-1,3,5-triazine onto polyvinylamine. The intermediate 2-chloro-4,6-bis-[(2,2,6,6-tetramethylpiperidin-4-yl)amino]-1,3,5-triazine and the obtained macromolecular light stabilizer were characterized by 1H NMR, HRMS, IR and UV spectroscopy. Cotton fabrics dyed with C.I. Reactive Yellow 145, C.I. Reactive Red 195 and C.I. Reactive Blue 19 were finished with the macromolecular light stabilizer, and the lightfastness of the dyes was tested. The results showed that the lightfastness of the reactive dyes was improved by 0.5-1.0 grade after being finished and the macromolecular light stabilizer exhibited good wash fastness and thermal stability.
2013, 24(2): 156-158
Abstract:
A novel fluorescent calcium indicator with a 490/582 nm ratiometric emission has been designed and synthesized. The indicator exhibits a highly selective ratiometric emission response to Ca2+ over other metal cations and a large Stokes shift of 202 nm. Moreover, its practical cell imaging capability for intracellular Ca2+ in the resting-and dynamic-state has been demonstrated in human umbilical vein endothelial cells using a confocal laser scanning microscope.
A novel fluorescent calcium indicator with a 490/582 nm ratiometric emission has been designed and synthesized. The indicator exhibits a highly selective ratiometric emission response to Ca2+ over other metal cations and a large Stokes shift of 202 nm. Moreover, its practical cell imaging capability for intracellular Ca2+ in the resting-and dynamic-state has been demonstrated in human umbilical vein endothelial cells using a confocal laser scanning microscope.
2013, 24(2): 159-162
Abstract:
The oxidation of formaldehyde in alkaline solution was studied by in situ rapid-scan time-resolved IR spectroelectrochemistry (RS-TR-FTIRS) method. In the potential range between 0.7 V and 0.2 V, the gem-diol anions were oxidized (according to the 2765 cm-1 of vH-O and 1034 cm-1 of vCO downward IR bands) and the formate ions appeared (according to the 1588, 1357 cm-1 of the asymmetric and symmetric vOCO and 1380 cm-1 of δC-H upward IR bands) in aqueous solution. It was also confirmed that gem-diol anion was oxidized (according to the 2026, 1034 cm-1 downward IR bands) to formate ions (according to the 1595, 1357, 1380 cm-1 upward IR bands) and water (according to the 3427 cm-1 of vH-O upward IR band) in heavy water solution. The results illustrated that formaldehyde formed gem-diol anion in alkaline solution and was absorbed on the electrode surface; then gem-diol anion was oxidized to formate ions and water.
The oxidation of formaldehyde in alkaline solution was studied by in situ rapid-scan time-resolved IR spectroelectrochemistry (RS-TR-FTIRS) method. In the potential range between 0.7 V and 0.2 V, the gem-diol anions were oxidized (according to the 2765 cm-1 of vH-O and 1034 cm-1 of vCO downward IR bands) and the formate ions appeared (according to the 1588, 1357 cm-1 of the asymmetric and symmetric vOCO and 1380 cm-1 of δC-H upward IR bands) in aqueous solution. It was also confirmed that gem-diol anion was oxidized (according to the 2026, 1034 cm-1 downward IR bands) to formate ions (according to the 1595, 1357, 1380 cm-1 upward IR bands) and water (according to the 3427 cm-1 of vH-O upward IR band) in heavy water solution. The results illustrated that formaldehyde formed gem-diol anion in alkaline solution and was absorbed on the electrode surface; then gem-diol anion was oxidized to formate ions and water.
2013, 24(2): 163-166
Abstract:
A recombinant allophycocyanin trimer was successfully immobilized on a mesoporous TiO2 electrode. The formation of the immobilized surface was confirmed bymultilayer adsorption of protein complexes. The key biophotovoltaic parameters were obtained, which showed that the recombinant allophycocyanin trimer could be a candidate for photosensitizer materials. The values of short-circuit current, open-circuit voltage, fill factor, and conversion efficiency were up to 0.73 mA/cm2, 0.52 V, 0.69, and 0.26%, respectively.
A recombinant allophycocyanin trimer was successfully immobilized on a mesoporous TiO2 electrode. The formation of the immobilized surface was confirmed bymultilayer adsorption of protein complexes. The key biophotovoltaic parameters were obtained, which showed that the recombinant allophycocyanin trimer could be a candidate for photosensitizer materials. The values of short-circuit current, open-circuit voltage, fill factor, and conversion efficiency were up to 0.73 mA/cm2, 0.52 V, 0.69, and 0.26%, respectively.
2013, 24(2): 167-169
Abstract:
ZnO-Al2O3 composite particles composed of ZnO nanosheets (thickness of 40-80 nm) on alumina particles were prepared by heterogeneous precipitation method using bayerite seed particles. The asprepared composite particles were characterized in terms of crystal structure,morphology, surface area and pore volume. The composite particles were used as sorbent for H2S adsorption at low temperature, and were compared with pure ZnO sorbent. The composite sorbent showed a greater sulfur adsorption capacity (0.052 g/g) than pure form of ZnO (0.028 g/g). This significant improvement was mainly attributed to higher surface area, more pore volume and unique morphology in nanoscale, which were also obtained by low cost presented method in this work for synthesis of ZnO sorbent supported on alumina particles.
ZnO-Al2O3 composite particles composed of ZnO nanosheets (thickness of 40-80 nm) on alumina particles were prepared by heterogeneous precipitation method using bayerite seed particles. The asprepared composite particles were characterized in terms of crystal structure,morphology, surface area and pore volume. The composite particles were used as sorbent for H2S adsorption at low temperature, and were compared with pure ZnO sorbent. The composite sorbent showed a greater sulfur adsorption capacity (0.052 g/g) than pure form of ZnO (0.028 g/g). This significant improvement was mainly attributed to higher surface area, more pore volume and unique morphology in nanoscale, which were also obtained by low cost presented method in this work for synthesis of ZnO sorbent supported on alumina particles.
2013, 24(2): 170-172
Abstract:
Sol-gel-derived bioactive calcium silicates, synthesized from calcium nitrate tetrahydrate and calcium 2-methoxyethoxide as calcium precursor respectively, were calcified under different temperatures. A series of techniques including SEM, TGA, solid 29Si NMR, nitrogen adsorption, and simulated body fluids (SBF) soaking were employed to study their textural features and in vitro bioactivity. It was confirmed that calcium 2-methoxyethoxide is a promising candidate of calcium precursor for bioactive calcium silicates stabilized under low temperatures. This has implications in fabrication of organic-inorganic hybrid composites.
Sol-gel-derived bioactive calcium silicates, synthesized from calcium nitrate tetrahydrate and calcium 2-methoxyethoxide as calcium precursor respectively, were calcified under different temperatures. A series of techniques including SEM, TGA, solid 29Si NMR, nitrogen adsorption, and simulated body fluids (SBF) soaking were employed to study their textural features and in vitro bioactivity. It was confirmed that calcium 2-methoxyethoxide is a promising candidate of calcium precursor for bioactive calcium silicates stabilized under low temperatures. This has implications in fabrication of organic-inorganic hybrid composites.
2013, 24(2): 173-176
Abstract:
Herein, a facile and effective approach was proposed for visualizing latent fingerprints (LFPs) on two kinds of conductive surfaces by spatially selective electrochemical deposition of Prussian blue (PB) thin films. This strategy exploited the fingerprint residue as an insulating mask and the PB thin films were only generated on the bare surface including the valleys between the papillary ridges, which produced a negative image of LFPs with high resolution up to the third level information. The surface morphology of PB films was characterized by the field emission scanning electron microscopy (FE-SEM). This enhancement technique showed promising performance in selected materials of practical interest.
Herein, a facile and effective approach was proposed for visualizing latent fingerprints (LFPs) on two kinds of conductive surfaces by spatially selective electrochemical deposition of Prussian blue (PB) thin films. This strategy exploited the fingerprint residue as an insulating mask and the PB thin films were only generated on the bare surface including the valleys between the papillary ridges, which produced a negative image of LFPs with high resolution up to the third level information. The surface morphology of PB films was characterized by the field emission scanning electron microscopy (FE-SEM). This enhancement technique showed promising performance in selected materials of practical interest.
