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2006 Volume 17 Issue 9
2006, 17(9): 1137-1140
Abstract:
The tetrahydroquinoline moiety is a structural feature of many natural products. By using a domino reaction of aromatic amines and cyclic enol ethers catalyzed by zirconyl chloride in water, various tetrahydroquinoline derivatives were synthesized efficiently. Most cyclized products showed cis selectivity. The cis selectivity was tentatively rationalized due to chelation control in water.
The tetrahydroquinoline moiety is a structural feature of many natural products. By using a domino reaction of aromatic amines and cyclic enol ethers catalyzed by zirconyl chloride in water, various tetrahydroquinoline derivatives were synthesized efficiently. Most cyclized products showed cis selectivity. The cis selectivity was tentatively rationalized due to chelation control in water.
2006, 17(9): 1141-1144
Abstract:
A series of novel phenoxazinone derivatives (1-6) were designed and synthesized for evaluating their antitumor activities. The antiproliferative activities of the prepared compounds against representative human neoplastic cell lines were evaluated by MTT assay. The results showed that most of them inhibited cell proliferation in a submicromolar to micromolar range.These compounds were also evaluated against KBv200 and MCF-7/Adr cell lines, which overexpress the MDR/P-glycoprotein drug efflux pump responsible for drug resistance, and had a more potential for resisting MDR than their lead compound APO.
A series of novel phenoxazinone derivatives (1-6) were designed and synthesized for evaluating their antitumor activities. The antiproliferative activities of the prepared compounds against representative human neoplastic cell lines were evaluated by MTT assay. The results showed that most of them inhibited cell proliferation in a submicromolar to micromolar range.These compounds were also evaluated against KBv200 and MCF-7/Adr cell lines, which overexpress the MDR/P-glycoprotein drug efflux pump responsible for drug resistance, and had a more potential for resisting MDR than their lead compound APO.
2006, 17(9): 1145-1148
Abstract:
A novel and efficient route of synthesizing 1, 2, 4-triazoline-5-ones is reported. The title compounds can be prepared in high yield and purity by the one-pot oxidation and cyclization of 1-acylthiosemicarbazides. The reaction is regioselective and stereoselective. The reaction condition is mild.
A novel and efficient route of synthesizing 1, 2, 4-triazoline-5-ones is reported. The title compounds can be prepared in high yield and purity by the one-pot oxidation and cyclization of 1-acylthiosemicarbazides. The reaction is regioselective and stereoselective. The reaction condition is mild.
2006, 17(9): 1149-1151
Abstract:
An efficient protocol for the synthesis of N6-(2-Hydroxyethyl)adenosine and its analogues through nucleophilic substitution was developed. All the reactions were completed in 10 min under microwave irradiation. Using water as solvent makes our method eco-friendly and easy to handle with.
An efficient protocol for the synthesis of N6-(2-Hydroxyethyl)adenosine and its analogues through nucleophilic substitution was developed. All the reactions were completed in 10 min under microwave irradiation. Using water as solvent makes our method eco-friendly and easy to handle with.
2006, 17(9): 1152-1154
Abstract:
The compound sulforaphane (SFN, 1) has been synthesized via a facile and green synthetic strategy based on the modification of previous methods. Because of its high bioactivities and rare content in nature, the present work is of great important significance.
The compound sulforaphane (SFN, 1) has been synthesized via a facile and green synthetic strategy based on the modification of previous methods. Because of its high bioactivities and rare content in nature, the present work is of great important significance.
2006, 17(9): 1155-1158
Abstract:
Methyl-(γ-chloropropyl)dichlorosilane was synthesized under the catalysis of a silicasupported Karstedt-type catalyst. By orthogonal experimental design method, the optimum reaction parameters such as reactants ratio, reaction temperature and time, and the dosage of catalyst, were determined. At the optimum reaction condition the product yield reached 78.42%, which is higher than that reported in the literatures.
Methyl-(γ-chloropropyl)dichlorosilane was synthesized under the catalysis of a silicasupported Karstedt-type catalyst. By orthogonal experimental design method, the optimum reaction parameters such as reactants ratio, reaction temperature and time, and the dosage of catalyst, were determined. At the optimum reaction condition the product yield reached 78.42%, which is higher than that reported in the literatures.
2006, 17(9): 1159-1161
Abstract:
Polysiloxane was a good solvent for hydrosilation reaction of carbosilane dendrimers with pentafluorophenyl core and HSiMe2(CH2)3C6F5. A new kind of dendrimer with both pentafluorophenyl core and terminal groups was synthesized. The studies showed that with the increase of fluorination, the viscosity values of carbosilane dendrimers decreased.
Polysiloxane was a good solvent for hydrosilation reaction of carbosilane dendrimers with pentafluorophenyl core and HSiMe2(CH2)3C6F5. A new kind of dendrimer with both pentafluorophenyl core and terminal groups was synthesized. The studies showed that with the increase of fluorination, the viscosity values of carbosilane dendrimers decreased.
2006, 17(9): 1162-1164
Abstract:
A series of chiral N-Boc-α-aminoaldehydes were synthesized in good yields and high purity via esterification of Boc-L-amino acids followed by reduction with sodium bis (2-methoxyethoxy)aluminum hydride.
A series of chiral N-Boc-α-aminoaldehydes were synthesized in good yields and high purity via esterification of Boc-L-amino acids followed by reduction with sodium bis (2-methoxyethoxy)aluminum hydride.
2006, 17(9): 1165-1168
Abstract:
Triacetylbenzene was prepared from tribenzimidazolium salt and Grignard reagent.The addition-hydrolysis reaction of tribenzimidazolium salt with Grignard reagent is reported and a novel method for preparation of triacetylbenzene is provided.
Triacetylbenzene was prepared from tribenzimidazolium salt and Grignard reagent.The addition-hydrolysis reaction of tribenzimidazolium salt with Grignard reagent is reported and a novel method for preparation of triacetylbenzene is provided.
2006, 17(9): 1169-1172
Abstract:
The NMR spectra revealed that the calixarene frame of 1, 3-disubstituted calix[4]arenes bearing optically active groups is asymmetric, even without the formation of a sub-ring. This inherent chirality arises from the interaction of the two chiral groups, which hinder the substituents' free rotation. Thus, these chiral calix[4]arenes display good chiral recognition ability.
The NMR spectra revealed that the calixarene frame of 1, 3-disubstituted calix[4]arenes bearing optically active groups is asymmetric, even without the formation of a sub-ring. This inherent chirality arises from the interaction of the two chiral groups, which hinder the substituents' free rotation. Thus, these chiral calix[4]arenes display good chiral recognition ability.
2006, 17(9): 1173-1176
Abstract:
The asymmetric oxidation of sulfides catalyzed by WO3 and 30% H2O2 in the presence of salan as chiral ligands under heterogeneous conditions is described. The reaction system is very easily to be operated. Mild to high chemical yields and moderate enantioselectivities were obtained.
The asymmetric oxidation of sulfides catalyzed by WO3 and 30% H2O2 in the presence of salan as chiral ligands under heterogeneous conditions is described. The reaction system is very easily to be operated. Mild to high chemical yields and moderate enantioselectivities were obtained.
2006, 17(9): 1177-1180
Abstract:
Twenty two sapriparaquinone derivatives were synthesized and their antioxidant activities were evaluated in vitro. Many of this kind of compounds demonstrated potent antioxidant activity against lipid peroxidation, especially compound 7 (IC50=3.7 μg/mL). The preliminary structure-activity relationship of sapriparaquinone derivatives was discussed.
Twenty two sapriparaquinone derivatives were synthesized and their antioxidant activities were evaluated in vitro. Many of this kind of compounds demonstrated potent antioxidant activity against lipid peroxidation, especially compound 7 (IC50=3.7 μg/mL). The preliminary structure-activity relationship of sapriparaquinone derivatives was discussed.
2006, 17(9): 1181-1184
Abstract:
Sixteen new 2-heterocyclomethyl-5-diphenylmethylenecyclopentanone hydrochlorides were designed and synthesized. The growth inhibitory effect of these compounds in vitro was conducted using a MTT assay in human breast cancer T47D cells.
Sixteen new 2-heterocyclomethyl-5-diphenylmethylenecyclopentanone hydrochlorides were designed and synthesized. The growth inhibitory effect of these compounds in vitro was conducted using a MTT assay in human breast cancer T47D cells.
2006, 17(9): 1185-1188
Abstract:
We reported the synthesis of a simple bifunctional molecule and the interaction between this molecule and DNA were studied by UV and the DNA cleavage behavoior was determined by agarose gel electrophoresis.
We reported the synthesis of a simple bifunctional molecule and the interaction between this molecule and DNA were studied by UV and the DNA cleavage behavoior was determined by agarose gel electrophoresis.
2006, 17(9): 1189-1192
Abstract:
Novel tetralin compounds were designed and synthesized on the three-dimensional model of lanosterol 14α-demethylase of Candida albicans. All of the lead compounds exhibited potent antifungal activities, especially compounds 16, 20. The mode of the action of the lead compounds was different from that of azoles. The present study affords the possibility to develop novel antifungal agents that specifically interact with the amino acid residues in the active site and avoid the serious toxicity arising from coordination binding with the heme of mammalian P450s.
Novel tetralin compounds were designed and synthesized on the three-dimensional model of lanosterol 14α-demethylase of Candida albicans. All of the lead compounds exhibited potent antifungal activities, especially compounds 16, 20. The mode of the action of the lead compounds was different from that of azoles. The present study affords the possibility to develop novel antifungal agents that specifically interact with the amino acid residues in the active site and avoid the serious toxicity arising from coordination binding with the heme of mammalian P450s.
2006, 17(9): 1193-1196
Abstract:
A novel low-density lipoprotein adsorbent was prepared simply by directly phosphonating porous cellulose beads. Tests in vitro demonstrated that this adsorbent showed quite good adsorption performance for selective removal of low-density lipoprotein from human plasma. The effects of preparation conditions on the lipoprotein sorption properties of the resulted adsorbent were investigated. The adsorption dynamics was also examined.
A novel low-density lipoprotein adsorbent was prepared simply by directly phosphonating porous cellulose beads. Tests in vitro demonstrated that this adsorbent showed quite good adsorption performance for selective removal of low-density lipoprotein from human plasma. The effects of preparation conditions on the lipoprotein sorption properties of the resulted adsorbent were investigated. The adsorption dynamics was also examined.
2006, 17(9): 1197-1200
Abstract:
Two artificial minic polypeptides which are synthetic analogues of natural products with DNA affinity were synthesized, and theirs cleavage activity with DNA were examined. The structures of these compounds was confirmed by 1H NMR, MS and IR.
Two artificial minic polypeptides which are synthetic analogues of natural products with DNA affinity were synthesized, and theirs cleavage activity with DNA were examined. The structures of these compounds was confirmed by 1H NMR, MS and IR.
2006, 17(9): 1201-1204
Abstract:
A new acylated iridoid glucoside, namely, 2'-O-(5-phenyl-2E, 4E-pentadienoyl)-mussaenosidic acid, was isolated from the aerial parts of the mangrove plant Avicennia marina.The structure of the new compound was established on the basis of various NMR spectroscopic analyses, including 2D NMR techniques (1H-1H COSY, HMQC, and HMBC) and HR-FAB-MS.This compound displayed moderate antioxidant activity.
A new acylated iridoid glucoside, namely, 2'-O-(5-phenyl-2E, 4E-pentadienoyl)-mussaenosidic acid, was isolated from the aerial parts of the mangrove plant Avicennia marina.The structure of the new compound was established on the basis of various NMR spectroscopic analyses, including 2D NMR techniques (1H-1H COSY, HMQC, and HMBC) and HR-FAB-MS.This compound displayed moderate antioxidant activity.
2006, 17(9): 1205-1208
Abstract:
Two new norisoprenoid derivatives have been isolated from the red alga Gymnogongrus flabelliformis. Their structures were elucidated as (3R, 6R, 7E)-(+)-3-O-phenylacetyl-4, 7-megastigmadiene-9-one and (3R, 7E)-(-)-3-O-phenylacetyl-5, 7-megastigmadiene-9-one, respectively, by spectroscopic methods including HRMS, 1D and 2D NMR techniques.
Two new norisoprenoid derivatives have been isolated from the red alga Gymnogongrus flabelliformis. Their structures were elucidated as (3R, 6R, 7E)-(+)-3-O-phenylacetyl-4, 7-megastigmadiene-9-one and (3R, 7E)-(-)-3-O-phenylacetyl-5, 7-megastigmadiene-9-one, respectively, by spectroscopic methods including HRMS, 1D and 2D NMR techniques.
2006, 17(9): 1209-1212
Abstract:
In this paper, a double artificial neural network (DANN) algorithm was used to parse near infrared (NIR) reflectance spectrum of Cofrel medicines. The contents of benproperine phosphate, which is the effective ingredient in Cofrel medicines, were accurately nondestructive quantitatively predicted. Compared the results with those of HPLC, the relative errors (RE%)were less than 0.18%. The analytical results could be applied to qualitative control of Cofrel medicines.
In this paper, a double artificial neural network (DANN) algorithm was used to parse near infrared (NIR) reflectance spectrum of Cofrel medicines. The contents of benproperine phosphate, which is the effective ingredient in Cofrel medicines, were accurately nondestructive quantitatively predicted. Compared the results with those of HPLC, the relative errors (RE%)were less than 0.18%. The analytical results could be applied to qualitative control of Cofrel medicines.
2006, 17(9): 1213-1216
Abstract:
A new chiral stationary phase of 3, 5-dimethylphenylcarbamates of cellulose, chemically bonded to 3-aminopropylsilica gel at the 6-positions of the glucose units, was prepared.The solvent versatility of the CSP was investigated for the enantioselective separation of four pairs of enantiomers using THF and chloroform as non-standard mobile phase eluent in HPLC. The influence of temperature on the resolution was investigated.
A new chiral stationary phase of 3, 5-dimethylphenylcarbamates of cellulose, chemically bonded to 3-aminopropylsilica gel at the 6-positions of the glucose units, was prepared.The solvent versatility of the CSP was investigated for the enantioselective separation of four pairs of enantiomers using THF and chloroform as non-standard mobile phase eluent in HPLC. The influence of temperature on the resolution was investigated.
2006, 17(9): 1217-1220
Abstract:
A method for the determination of trace mercury in water samples by hydride generation atomic absorption spectrophotometry after cloud point extraction was proposed in the present work.The effects of pH, concentration of surfactant, and equilibration time on cloud point extraction were discussed. The enhancement factor of 20 and the detection limit of 0.039 μg/L were obtained for mercury with relative standard deviation of 4.8% (n=11).
A method for the determination of trace mercury in water samples by hydride generation atomic absorption spectrophotometry after cloud point extraction was proposed in the present work.The effects of pH, concentration of surfactant, and equilibration time on cloud point extraction were discussed. The enhancement factor of 20 and the detection limit of 0.039 μg/L were obtained for mercury with relative standard deviation of 4.8% (n=11).
2006, 17(9): 1221-1224
Abstract:
A highly sensitive method is developed for the determination of trace amounts of some heavy metal ions in aqueous solution based on the classical Belousov-Zhabotinskii (BZ) oscillating chemical system. Introducing of S2- ion makes the new oscillating system Ce(SO4)2-KBrO3-CH2(COOH)2-Na2S-H2SO4 have to a high sensitivity for some heavy metal ions such as Ag+, pb2+, Hg2+, Cd2+, Cu2+ and Bi3+ with detection limits down to 10-12 mol·L-1.
A highly sensitive method is developed for the determination of trace amounts of some heavy metal ions in aqueous solution based on the classical Belousov-Zhabotinskii (BZ) oscillating chemical system. Introducing of S2- ion makes the new oscillating system Ce(SO4)2-KBrO3-CH2(COOH)2-Na2S-H2SO4 have to a high sensitivity for some heavy metal ions such as Ag+, pb2+, Hg2+, Cd2+, Cu2+ and Bi3+ with detection limits down to 10-12 mol·L-1.
2006, 17(9): 1225-1228
Abstract:
Metabonomics, a novel systemic approach, was applied to studies of Traditional Chinese Medicine scutellarin in rat urine. The liquid chromatography coupled with ion trap mass spectrometry combined with PCA was used in this paper. With this methodology, two potential metabolites of scutellarin were detected and the nine ions responsible for the gender variation and one ion for the dosage variation were found.
Metabonomics, a novel systemic approach, was applied to studies of Traditional Chinese Medicine scutellarin in rat urine. The liquid chromatography coupled with ion trap mass spectrometry combined with PCA was used in this paper. With this methodology, two potential metabolites of scutellarin were detected and the nine ions responsible for the gender variation and one ion for the dosage variation were found.
2006, 17(9): 1229-1232
Abstract:
This paper reported a compact system of capacitively coupled contactless conductivity detection (C4D) based on the square wave excitation voltage for capillary electrophoresis, and it exhibited excellent sensitivity at the optimal frequency of 198 kHz. The feasibility and sensitivity of this detector was demonstrated by simultaneous detection of thirteen ions including alkali, alkaline earth and heavy metal ions. And the detection limits (S/N 3) were in the range of 0.2-1μmol/L for Mn2+, K+, Na+, Mg2+, Ca2+, Li+, Ba2+, and 7-25μmol/L for Ni2+, Cu2+, Cd2+, Pb2+, Co2+, Zn2+.
This paper reported a compact system of capacitively coupled contactless conductivity detection (C4D) based on the square wave excitation voltage for capillary electrophoresis, and it exhibited excellent sensitivity at the optimal frequency of 198 kHz. The feasibility and sensitivity of this detector was demonstrated by simultaneous detection of thirteen ions including alkali, alkaline earth and heavy metal ions. And the detection limits (S/N 3) were in the range of 0.2-1μmol/L for Mn2+, K+, Na+, Mg2+, Ca2+, Li+, Ba2+, and 7-25μmol/L for Ni2+, Cu2+, Cd2+, Pb2+, Co2+, Zn2+.
2006, 17(9): 1233-1235
Abstract:
The enhancing effect of benserazide on the chemiluminescence of luminol-potassium ferricyanide in alkaline medium was investigated, and a sensitive method for detecting benserazide has been developed by flow-injection chemiluminescence's. The experimental results showed that the emission intensity is proportional to the concentration of benserazide in the range of 0.01-1.0 μg/mL. The detection limit (S/N=3) for benserazide turned out to be 0.9 ng/mL, and the relative standard deviation for 11 determinations of a 0.10 μg/mL benserazide was 2.4%. The method was satisfactorily applied to the determination of benserazide in spiked urine samples.
The enhancing effect of benserazide on the chemiluminescence of luminol-potassium ferricyanide in alkaline medium was investigated, and a sensitive method for detecting benserazide has been developed by flow-injection chemiluminescence's. The experimental results showed that the emission intensity is proportional to the concentration of benserazide in the range of 0.01-1.0 μg/mL. The detection limit (S/N=3) for benserazide turned out to be 0.9 ng/mL, and the relative standard deviation for 11 determinations of a 0.10 μg/mL benserazide was 2.4%. The method was satisfactorily applied to the determination of benserazide in spiked urine samples.
2006, 17(9): 1236-1238
Abstract:
A novel thermo-sensitive switching membrane has been prepared by radiation-induced simultaneous grafting N-isopropylacrylamide (NIPAAm) onto chitosan membrane. Fourier transform infrared spectroscopy (FTIR) was used to identify the structure of the grafted membranes. The surface morphology of the grafted membrane was observed from scanning electron microscopy (SEM). Pure water flux measurements showed that water flux of the grafted membrane decreased with the increase of temperature, while that of chitosan membrane was constant. It was proved that grafted membrane was sensitive to temperature.
A novel thermo-sensitive switching membrane has been prepared by radiation-induced simultaneous grafting N-isopropylacrylamide (NIPAAm) onto chitosan membrane. Fourier transform infrared spectroscopy (FTIR) was used to identify the structure of the grafted membranes. The surface morphology of the grafted membrane was observed from scanning electron microscopy (SEM). Pure water flux measurements showed that water flux of the grafted membrane decreased with the increase of temperature, while that of chitosan membrane was constant. It was proved that grafted membrane was sensitive to temperature.
2006, 17(9): 1239-1242
Abstract:
A series of alumina samples were prepared using β-cyclodextrin as the non-surfactant template. These samples were characterized by XRD, BET and TEM. The results showed that the alumina samples prepared using β-cyclodextrin template had the higher surface areas (124-484 m2/g), larger pore volumes (0.7-1.27 mL/g) and more thermal stability than samples prepared without using β-cyclodextrin.
A series of alumina samples were prepared using β-cyclodextrin as the non-surfactant template. These samples were characterized by XRD, BET and TEM. The results showed that the alumina samples prepared using β-cyclodextrin template had the higher surface areas (124-484 m2/g), larger pore volumes (0.7-1.27 mL/g) and more thermal stability than samples prepared without using β-cyclodextrin.
2006, 17(9): 1243-1246
Abstract:
Molecularly imprinted polymers using 2, 4-dichlorophenoxyacetic acid (2, 4-D) as templates were prepared by suspension polymerization in silicon oil. The polymer particles exhibited regular shape in the micro-scale range. The adsorbing experiments indicated that the imprinted polymer particles possessed higher affinity to 2, 4-D than the non-imprinted polymer particles.
Molecularly imprinted polymers using 2, 4-dichlorophenoxyacetic acid (2, 4-D) as templates were prepared by suspension polymerization in silicon oil. The polymer particles exhibited regular shape in the micro-scale range. The adsorbing experiments indicated that the imprinted polymer particles possessed higher affinity to 2, 4-D than the non-imprinted polymer particles.
2006, 17(9): 1247-1250
Abstract:
Reversible addition-fragmentation transfer (RAFT) miniemulsion polymerizations for PMMA with cumyl dithiobenzoate (CDB) as a chain transfer agent (CTA) has been carried out.Higher temperature made the polymerization much faster and the PDI remained below 1.20, when the temperature was upon 70℃.
Reversible addition-fragmentation transfer (RAFT) miniemulsion polymerizations for PMMA with cumyl dithiobenzoate (CDB) as a chain transfer agent (CTA) has been carried out.Higher temperature made the polymerization much faster and the PDI remained below 1.20, when the temperature was upon 70℃.
2006, 17(9): 1251-1254
Abstract:
In this paper we report the peripheral functionalization of amine-terminated second generation poly(amidoamine) (PAMAM) with 9-anthracenecarboxalehyde and the preparation of dendrimer-encapsulated metal salts. The interesting different behaviors of these hybrid materials were observed by fluorescence and UV-Vis spectra.
In this paper we report the peripheral functionalization of amine-terminated second generation poly(amidoamine) (PAMAM) with 9-anthracenecarboxalehyde and the preparation of dendrimer-encapsulated metal salts. The interesting different behaviors of these hybrid materials were observed by fluorescence and UV-Vis spectra.
2006, 17(9): 1255-1258
Abstract:
The changes in crystalline properties of starch from Rhizoma Dioscorea by acid hydrolysis was characterized by X-Ray diffractometry (XRD). The results revealed that the crystalline type of Rhizoma Dioscorea starch changed from C-type to A-type after 16 days of the acid hydrolysis. This phenomenon was different from that of other starches subjected to the acid hydrolysis. The results revealed that the B-polymorphs of C-type starch constituted the amorphous regions while the crystalline areas were mainly composed of A-polymorphs. The degree of crystallinity of the acid-thinned starch increased gradually with the time of acid hydrolysis.
The changes in crystalline properties of starch from Rhizoma Dioscorea by acid hydrolysis was characterized by X-Ray diffractometry (XRD). The results revealed that the crystalline type of Rhizoma Dioscorea starch changed from C-type to A-type after 16 days of the acid hydrolysis. This phenomenon was different from that of other starches subjected to the acid hydrolysis. The results revealed that the B-polymorphs of C-type starch constituted the amorphous regions while the crystalline areas were mainly composed of A-polymorphs. The degree of crystallinity of the acid-thinned starch increased gradually with the time of acid hydrolysis.
2006, 17(9): 1259-1262
Abstract:
The oxygenation constants and thermodynamic parameter (△H°, △S°) of a series of novel Co (Ⅱ) complexes with phenol ether bridged dihydroxamic acids CoL1-CoL6 were measured, their catalytic performance in oxidation of p-xylene to p-toluic acid (PTA) were examined. The modulation of O2-binding capabilities and catalytic oxidation activities by X (X=Cl, OCH3) and Y(Y=H, CH3, Cl) groups bonded to the aromatic rings of the Co (Ⅱ) complexes were investigated.
The oxygenation constants and thermodynamic parameter (△H°, △S°) of a series of novel Co (Ⅱ) complexes with phenol ether bridged dihydroxamic acids CoL1-CoL6 were measured, their catalytic performance in oxidation of p-xylene to p-toluic acid (PTA) were examined. The modulation of O2-binding capabilities and catalytic oxidation activities by X (X=Cl, OCH3) and Y(Y=H, CH3, Cl) groups bonded to the aromatic rings of the Co (Ⅱ) complexes were investigated.
2006, 17(9): 1263-1266
Abstract:
Two novel V-shaped symmetric chromophores: E-2, 8-bis(4-vinyl-4-carbazol-9-yl)dibenzothiophene (abbreviated as SK-G1) and E-2, 8-bis(4-vinyl-4-triphenylamino) dibenzothiophene(abbreviated as ST-G1) have been synthesized and characterized. Their two photon absorption properties were measured by the open-aperture femtosecond Z-scan technique and the nanosecond nonlinear optical transmission (NLT), respectively, when pumped by Ti: sapphire laser at 750 nm and 800 nm.
Two novel V-shaped symmetric chromophores: E-2, 8-bis(4-vinyl-4-carbazol-9-yl)dibenzothiophene (abbreviated as SK-G1) and E-2, 8-bis(4-vinyl-4-triphenylamino) dibenzothiophene(abbreviated as ST-G1) have been synthesized and characterized. Their two photon absorption properties were measured by the open-aperture femtosecond Z-scan technique and the nanosecond nonlinear optical transmission (NLT), respectively, when pumped by Ti: sapphire laser at 750 nm and 800 nm.
2006, 17(9): 1267-1270
Abstract:
A new solid sorbent system is developed for the monitoring of dehydrogenated nicotine in the environment. The reagent system for the indicator tube consists of furfural-hydrochloric acid and phosphoric acid impregnated over a cellulose fibre (cotton) and a humectant calcium chloride. The reagent system has also been used for the preparation of reagent paper. After exposing the indicator tubes and test paper to dehydrogenated nicotine, for a constant time, the red-violet colour developed could be compared with those obtained from standards. Alternatively the coloured compound was extracted in water and the absorbance measured at 540 nm. The lower limit of detection is 0.03 μg/m3 of nicotine for the reagent papers and indicator tubes. The lower limit of determination by spectrophotometric procedure is 0.001 μg/m3 of air.The preparation of indicator tubes, test papers and their applications for the detection and determination of nicotine in environmental tobacco smoke (ETS), mainstream smoke (MS), side stream smoke (SS) and biological samples is described in this paper.
A new solid sorbent system is developed for the monitoring of dehydrogenated nicotine in the environment. The reagent system for the indicator tube consists of furfural-hydrochloric acid and phosphoric acid impregnated over a cellulose fibre (cotton) and a humectant calcium chloride. The reagent system has also been used for the preparation of reagent paper. After exposing the indicator tubes and test paper to dehydrogenated nicotine, for a constant time, the red-violet colour developed could be compared with those obtained from standards. Alternatively the coloured compound was extracted in water and the absorbance measured at 540 nm. The lower limit of detection is 0.03 μg/m3 of nicotine for the reagent papers and indicator tubes. The lower limit of determination by spectrophotometric procedure is 0.001 μg/m3 of air.The preparation of indicator tubes, test papers and their applications for the detection and determination of nicotine in environmental tobacco smoke (ETS), mainstream smoke (MS), side stream smoke (SS) and biological samples is described in this paper.
2006, 17(9): 1271-1274
Abstract:
A catalyst comprised novel high surface area alumina support was prepared to control emission of automobiles. The results showed that prepared catalyst could satisfy the requirements of a high performance close coupled catalyst for its good catalytic activity at low temperature and good stability at high temperature.
A catalyst comprised novel high surface area alumina support was prepared to control emission of automobiles. The results showed that prepared catalyst could satisfy the requirements of a high performance close coupled catalyst for its good catalytic activity at low temperature and good stability at high temperature.
2006, 17(9): 1275-1278
Abstract:
A novel method, i.e. molten salt method, was adopted to prepare potassium sodium titanate nanotubes. EDX results indicated that the ion-exchange reaction reached an equilibrium state at around 9 h. The 24 h ion-exchanged product maintained nano-tubular and its crystalline structure was consistent with that of Na2Ti2O4(OH)2 nanotubes. The nanotubes have a high specific surface area, possibly making this material a good candidate as controlled release materials, catalyst, electrode materials, etc..
A novel method, i.e. molten salt method, was adopted to prepare potassium sodium titanate nanotubes. EDX results indicated that the ion-exchange reaction reached an equilibrium state at around 9 h. The 24 h ion-exchanged product maintained nano-tubular and its crystalline structure was consistent with that of Na2Ti2O4(OH)2 nanotubes. The nanotubes have a high specific surface area, possibly making this material a good candidate as controlled release materials, catalyst, electrode materials, etc..
