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1.
A novel compound of butyl crystal violet lactone (BCVL) has been prepared by oxidizing leuco butyl crystal violet lactone (LBCVL), which was obtained by the mixture of N,N-dibutylaniline, p-(dibutylamino) benzaldehyde and methyl-m-(dibutylamino) benzoate. The structure of BCVL was characterized by 1H-nuclear magnetic resonance (NMR), infrared (IR), and mass spectrometry (MS). The color of BCVL can change reversibly in some acid or alkali solvents. The result of the dissolution experiment showed that solubility of BCVL in organic solvent was improved compared with crystal violet lactone (CVL). Translated from Journal of Fudan University (Natural Science), 2006, 45(3): 375–379 [译自: 复旦学报(自然科学版)]  相似文献   

2.
A water-soluble polysaccharide (CPS-0) was obtained from the root of Cudrania tricuspidata (Carr.) Bur., by hot water extraction (70°C), deproteination using enzymolysis and Sevag method, precipitation with ethanol, and fractionation through DEAE-Sephadex A-50 chromatography. The purity of CPS-0 was determined by HPLC and the structure was elucidated by monosaccharide composition analysis, methylation analysis, GC, GC-MS, NMR spectral (1H-NMR, 13C-NMR, HMQC), UV, IR, and elemental analysis. The CPS-0 was found to contain glucose residues only. The average repeating unit is a decasaccharide having a backbone consisting of 1,4-linked α-D-glucopyranosyl residues to which the side chain consisting of terminal and 1,4-linked α-D-glucopyranosyl residues was attached at position 6 of the branching residues. __________ Translated from Chemical Journal of Chinese Universities, 2007, 28(6): 1088–1091 [译自: 高等学校化学学报]  相似文献   

3.
Sr2CeO4/Ln3+ (Ln = Er, Ho, Tm) phosphors were synthesized with the microwave radiation method for the first time. The luminescent properties of the samples were investigated and the up-conversion luminescence of Er3+, Ho3+ and Tm3+ doped Sr2CeO4 phosphors was observed. The spectra indicate that the energy transfer takes place from the triplet excited state of MLCT (metal-to-ligand charge transfer) state for Sr2CeO4 (sensitizer) to the rare earth ions (activator). __________ Translated from Journal of Hebei Normal University (Natural Science Edition), 2007, 31(2): 212–216 [译自: 河北师范大学学报 (自然科学版)]  相似文献   

4.
A novel calix[4]arene-based fluorescent chemosensor bearing a 2-aminopyridine moiety and a naphthalenic fluorophore was synthesized The chemical structure of the product was elucidated by FT-IR, MS-FAB, NMR and elemental analyses. Then, the properties and identification mechanism of the synthesized chemosensor were investigated. The results show that the chemosensor exhibits selective fluorescent quenching in the presence of aromatic organic acid in acetonitrile solution, and that the binding ability of the chemosensor with organic acid is in the order of p-cyanic-benzyl acid > p-chloric-benzyl acid > p-methoxyl-benzyl acid > benzyl acid. __________ Translated from Journal of South China University of Technology (Natural Science Edition), 2007, 35(4): 20–24 [译自: 华南理工大学学报(自然科学版)]  相似文献   

5.
The synthesis of the first two arylenealkyne conjugated macrocycles containing a long alkylene bridge via Glaser coupling of template-directed tetraacetylenes was reported. Tetraacetylene intermediates with complex structures were constructed rapidly via quadruple Hagihara coupling of monoprotected bisacetylenes to appropriate tetraiodides and subsequent desilylation. The characterization of such compounds was carried out by NMR, GPC and UV-Vis spectra. Unfortunately, the two compounds were not liquid crystals and had no biaxial nematic mesophase character as expected. __________ Translated from Chemical Journal of Chinese Universities, 2007, 28(1): 65–70 [译自: 高等学校化学学报]  相似文献   

6.
The electrochemical behavior of ciprofloxacin (CFX) and its interaction with the natural calf thymus DNA (ctDNA) is studied by using pulse difference voltammetry on a carbon electrode. CFX shows a well-defined oxidative peak at + 0.88 V. As a result of reaction with ctDNA,the oxidative peak of CFX decreased markedly. According to the electrochemical equation deduced in this paper, the binding constant of 1.36 × 105 (mol/L)−1 and the binding size of 1.94 (base pairs) of CFX with ctDNA were obtained by nonlinear fit analysis of the electrochemical data. The mechanism of the interaction was explored. __________ Translated from Journal of Zhejiang University (Science Edition), 2007, 34(3): 330–334 [译自: 浙江大学学报(自然科学版)]  相似文献   

7.
According to the Ullman reaction mechanism, the synthesis of 1,5-di(o-anisidino)anthraquinone was achieved by the multiphase reaction of 1,5-dichloroanthraquinone in xylene and o-anisidine in the presence of copper metal powder and potassium acetate. The effects of various factors on the reaction, such as the dosages of xylene and catalyst, molar ratios of raw materials, and reaction times were investigated. When the molar ratio of 1,5-dichloroanthraquinone to o-anisidine and potassium acetate is 1:10:2.5 and the catalyst dosage based on 1,5-dichloroanthraquinone is 5.3%, the conversion of 1,5-dichloroanthraquinone is 97.8% and the yield of 1,5-di(o-anisidino)anthraquinone is 80.6% after reflux for 10 h. Under these conditions, the recovery of the solvent is 86.0%. The target compound was identified by MS, 1H NMR, IR and DSC. __________ Translated from Journal of Dalian University of Technology, 2007, 47(2): 170–174 [译自: 大连理工大学学报]  相似文献   

8.
In order to search for better acetylcholinesterase (AchE) inhibitors, the binding properties of AchE with huperizine E, which is a derivative of huperzine A, were investigated with 1H nuclear magnetic resonance (1H NMR) method. The nonselective, selective and double-selective spin-lattice relaxation rates of some protons in huperzine E were acquired in the absence and presence of AchE at a concentration ratio of [ligand]/[protein] = 1: 0.005. The enhancements of selective relaxation rates of these protons were obvious after adding AchE. The molecular motional correlation times of two pairs of protons, H-1a/H-1b and H-2/H-3, in the bound state at T = 298 K were 11.7 and 9.46 ns respectively, while they were 27.7 and 35.2 ps in the free state. All of these show that huperzine E has high binding affinity with AchE. __________ Translated from Acta Chimica Sinica, 2007, 65(5): 415–420 [译自: 化学学报]  相似文献   

9.
Fe3+-doped TiO2 composite nanoparticles with different doping amounts were successfully synthesized using sol-gel method and characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and ultravioletvisible spectroscopy (UV-Vis) diffuse reflectance spectra (DRS). The photocatalytic degradation of methylene blue was used as a model reaction to evaluate the photocatalytic activity of Fe3+/TiO2 nanoparticles under visible light irradiation. The influence of doping amount of Fe3+ (ω: 0.00%–3.00%) on photocatalytic activities of TiO2 was investigated. Results show that the size of Fe3+/TiO2 particles decreases with the increase of the amount of Fe3+ and their absorption spectra are broaden and absorption intensities are also increased. Doping Fe3+ can control the conversion of TiO2 from anatase to rutile. The doping amount of Fe3+ remarkably affects the activity of the catalyst, and the optimum efficiency occurs at about the doping amount of 0.3%. The appropriate doping of Fe3+ can markedly increase the catalytic activity of TiO2 under visible light irradiation. __________ Translated from Journal of Northwest Normal University (Natural Science), 2006, 42(6): 55–56 [译自: 西北师范大学学报(自然科学版)]  相似文献   

10.
Nanometer MgO was prepared via a sol-gel auto-combustion technique using magnesium nitrate as raw material and citric acid as chelating agent. IR spectra of the dried gel were used to investigate the structure of the precursors. By studying the different TG curves of magnesium citrate gel prepared by different methods, we found that a combustion process occurred and the nitrate ions acted as an oxidant in the combustion process. TEM photographs of synthesized powders from the sol-gel auto-combustion showed that the crystallites were uniform in size. In addition, the XRD pattern of this sample showed that the particle size was 8.9 nm. The BET curves, in turn, showed that the specific surface of the sample was 26.34 m2/g. The mechanism of the frothing process in restraining agglomeration is discussed. __________ Translated from Journal of East China Normal University (Natural Science), 2007, (2): 52–57 [译自: 华东师范大学学报(自然科学版)]  相似文献   

11.
To study the bioactive constituents from Andrographis paniculata, two compounds were isolated and purified by column chromatography on AB-8 macro-porous adsorption resin and polyamide. Their structures were determined by various spectroscopic methods, including UV, FABMS, 1H-NMR, 13C-NMR, DQFCOSY, TOCSY, HMQC, HMBC, and NOESY. The 1H-NMR and 13C-NMR signals of the two compounds were assigned. The structures of the two compounds were elucidated as 5,4′-dihydroxy-7-methoxyflavone-6-yl-β-D-glucopyranoside and 5,4′-dihydroxy-7-methoxyflavone-8-yl-β-Dglucopyranoside, respectively. __________ Translated from Acta Chimica Sinica, 2007, 65(14): 1399–1402 [译自: 化学学报]  相似文献   

12.
Mesoporous aluminophosphate was prepared by using G4.0 poly(amido amine)dendrimer as a template and characterized by Fourier transform infrared spectrometer (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM) and N2 adsorption/desorption methods. Results show that the title compound exhibits a typical mesoporous structure with the average pore size from 5 to 8 nm. The formation mechanism of the nanoporous structure using dendrimer as a template was also discussed. __________ Translated from Journal of Fujian Normal University (Natural Science Edition), 2007, 23(2): 67–70 [译自: 福建师范大学学报 (自然科学版)]  相似文献   

13.
An investigation of the copolymerization of allyl glycidyl ether (AGE) with methyl acrylate (MA) was performed in the presence of benzyl imidazole-1-carbodithioate (BICDT) on the thermal initiation condition. Results showed that the process has good characteristics of living free radical polymerization, i.e. the molecular weight of the obtained polymer increases linearly with monomer conversion, molecular weight distribution is very narrow, and a linear relationship between ln([M]0/[M]) and polymerization time is found. The copolymer structure containing epoxy groups was demonstrated from the 1H nuclear magnetic resonance (1H NMR) spectrum. It was found that the content of AGE in the copolymer increases with the increase in monomer conversion and molar faction of the AGE in the monomer feed. However, the polymerization could slow down when the fraction of AGE increases in the monomer feed. Taking advantage of living polymerization character, functional block copolymers PSt-b-P (MA-co-AGE) were prepared in the presence of PSt RAFT agent. __________ Translated from Journal of Anhui University of Science and Technology, 2006, 26(3): 56–61 [译自: 安徽理工大学学报]  相似文献   

14.
The hydrophobic formation cationic starch (PSOAMDA) was prepared from starch (St), octadecyl acrylate (OA), acrylamide (AM) and dimethyl diallyl ammonium chloride (DMDAAC) by means of inverse suspension polymerization with redox initiator. Water with algae from Dianchi Lake was tested with PSOAMDA. Results show that when the molar ratio of St: AM: DMDAAC: OA is 4:8:1.5:0.6 and the reaction temperature is 40°C with a reaction time of 3 h, the monomer conversion yield, graft percentage and cationic degree is 92.4%, 63.8% and 7.3%, respectively, and M η = 3.26×106 g/vmol. It had been found from the flocculation of disposed water with algae from Dianchi Lake that the transparency and COD elimination reach to 93.5% and 70.3%, respectively, with 15 mg/L PSOAMDA and at pH 6, vs. 91.3% and 69.2% obtained with the commercial cationic polyacrylamide (PAM-C). When PSOAMDA dosage is 10–25 mg/L and the pH of aqueous solution is 6–10, the flocculation performance is well capable of dealing with the water with algae from Dianchi Lake. __________ Translated from Journal of Yunnan University (Natural Sciences Edition), 2007, 29(2): 177–182 [译自: 云南大学学报(自然科学版)]  相似文献   

15.
The bimetallic complex of Ni2Co(TTHA)·12H2O (TTHA = triethylene tetraminehexaacetic acid) was synthesized and characterized structurally and magnetically. The title complex crystallizes in the triclinic space group P ī with a = 0.7316(2), b = 0.8624(2), c = 1.5041(4) nm; α = 73.38(2), β = 83.97(2), γ = 70.50(2)°. The crystal structure is built up of [Ni2(TTHA)(H2O)2]2−, Co(H2O)62+ and water molecules. The variable magnetic measurement shows that there is strong antiferromagnetic interaction between two Ni(II) ions in [Ni2(TTHA) (H2O)2]2− with J Ni−Ni = −141.64 cm−1, g Ni = 2.21 and that the constant of spin-orbit coupling of Co(II) ion is −134.8 cm−1. __________ Translated from Acta Scientiarum Naturalium Universitatis Nankaiensis, 2007, 40(1): 6–10 [译自: 南开大学学报(自然科学版)]  相似文献   

16.
ZnS hollow nanospheres with holes were prepared by reacting ZnSO4 with H2S, the sulfide source formed in the reaction of CS2 with ethylenediamine, 1,3-propylenediamine, butylamine or 2-(2-aminoethylamino) ethanol, which also acted as a template agent, at 50°C under agitation. The shape, particle size of about 100–850 nm and hole size of about 150–600 nm of ZnS hollow nanospheres with holes were shown by SEM and TEM images. These ZnS nanospheres with β cubic ZnS phase and composed of 2–5 nm nanocrystals were characterized by XRD and HRTEM. The blue shift of maximum absorption in UV-vis displayed the effect of quantum size. The two amino groups of amine templates reacted favorably with Zn2+ to form uniform and relatively smooth ZnS nanospheres with holes, while hydroxyethyl played a disadvantageous role. A reasonable mechanism of hole formation by H2S rushing out is suggested. __________ Translated from Journal of Jinan University (Natural Science), 2007, 28(1): 92–95 [译自: 暨南大学学报(自然科学版)]  相似文献   

17.
Based on the SAR (structure activity relationship) of TZDs (thiazolidinediones), 3-methyl-1-phenyl-2-pyrazoline-5-one was selected as a substitute for TZD. Compounds of 3-methyl-1-phenyl-4-{4-[(5-methyl-2-phenyloxazol-4-yl)methoxy]benzylene(benzyl)}-2-pyrazol-5-one were designed and synthesized to find some more hypoglycemic active agents and further investigate the SAR of this class of compounds. Butanedione monoxime reacted with (substituted) benzaldehyde via cyclization and chlorination to give 4-(chloromethyl)-5-methyl-2-phenyloxazole derivatives, which condensed with 4-hydroxybenzaldehyde or vanillin, and was followed by the Knoevenagel reaction with 3-methyl-1-phenyl-2-pyrazol-5-one to give compounds Ia-Ih. Compounds Ia-Ih were hydrogenated with Pd-C to give IIa-IIh, and their hypoglycemic activity was evaluated with a glucose oxidase kit and insulin load test on normal mice. Sixteen new target compounds were synthesized. All the compounds were characterized by 1H NMR, IR, MS and elemental analysis. The preliminary pharmacological tests show that the compounds have good hypoglycemic activity and can enhance the action of insulin, especially Ib, Id and If. __________ Translated from Chemical Journal of Chinese Universities, 2007, 28(4): 672–677 [译自: 高等学校化学学报]  相似文献   

18.
The photodegradation of organic dye rhodamine B (RhB) in an aqueous solution was studied using a microwave electrodeless UV lamp (MWUVL). The 185 nm vacuum UV (VUV) intensity of the MWUVL amounted to 12% of the total UV output, about 1.7 times as high as that of the con ventional low-pressure mercury lamp. An acidic condition was preferred for the degradation of RhB. Precipitate was generated during RhB degradation when the initial concentration of RhB solution was above 60 mg · L−1. For 100 mg · L−1 RhB at pH 4.0, the mass of precipitate produced was nearly half of the initial amount of RhB in the solution after irradi ation for 75 min. The corresponding degradation ratio of RhB reached up to 99.4% and COD reduced 77.4%. The photo degradation of RhB is mainly achieved by direct photolysis of RhB by 185 nm and OH radical oxidation. __________ Translated from Journal of Fudan University (Natural Science), 2006, 45(6): 726–731 [译自: 复旦学报 (自然科学版)]  相似文献   

19.
A nano-alumina with high specific area was prepared using a homogeneous precipitation method with titanium dioxide and barium oxide as modifying additives. Results showed that 5 wt% TiO2 or BaO added in the alumina gels can decrease the particle size and increase the specific area, but excessive TiO2 or BaO could deteriorate the properties of α-Al2O3. __________ Translated from Journal of Shandong University of Technology (Natural Science Edition), 2007, 27(3): 23–26 [译自: 山东理工大学学报(自然科学版)]  相似文献   

20.
The rare earth Schiff base complex Nd (H2Salen)2Cl3·2C2H5OH was synthesized by a simple and convenient method and characterized by IR and elemental analysis. The catalyst system composed of Nd (H2Salen)2Cl3·2C2H5OH/Al(i-Bu)3/CCl4 is effective for the polymerization of styrene (St). The optimum conditions are as follows: [St]/[Nd] = 1000, [CCl4]/[Nd] = 9, [Al]/[Nd] = 30, and polymerization at 50°C for 20 h. The resulting polystyrene was characterized by NMR and GPC. The results of NMR show that the polymer obtained had a stereoregularity with 52.3% isotacticity and 47.7% syndiotacticity without any random structure. __________ Translated from Journal of Zhejiang University (Science Edition), 2007, 34(2): 189–196 [译自: 浙江大学学报(理学版)]  相似文献   

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