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1.
柠檬酸溶解-热解法合成纳米晶SnO2粉体   总被引:4,自引:0,他引:4  
The SnO2 nanocrystaline powders were synthesized by citric acid dissolution-pyrolysis method. The medium products were analyzed by FTIR. The products were characterized by TG-DTA, XRD, TEM, SEM etc. The results showed that the Sn was coordinated with aconitase acid during the dissolution. The SnO2 particles prepared by this method were with a mean size of 5~10 nm. The calcined products presented lacunose micro-arc structure, thus favoring the application as gas-sensitive materials.  相似文献   

2.
Ethyl 3-alkyl-4-hydroxy-2-thioxothiazolidine-4-carboxylates were prepared in excellent yields from the reaction of corresponding primary amines with carbon disulfide and ethyl 3-bromo-2-oxopropanoate in the presence of anhydrous potassium phosphate in DMF at room temperature within 1 h. The structures of the highly functionalized products were corroborated spectroscopically (IR, ^1H NMR, ^13C NMR, EI-MS) and by elemental analyses. A plausible mechanism for such type of cyclization was proposed.  相似文献   

3.
3, 3-Dimethyl-1-(1,2,4-triazol)-2-butanone was treated with aqueous formaldehyde to give an additional product, and subsequent elimination by acetic anhydride yielded 4,4-dimethyl-2-(1,2,4-triazol)-1-penten-3-one. Further addition with substituted amines provideda series of (1,2,4-triazol)-4,4-dimethyl-3-pentanone, which were then reduced by KBH4 to obtaina series of (1,2,4-triazol)-4,4-dimethyl-3-pentanol. Their structures were confirmed by ^1HNMR and elemental analysis. The results of bioassay showed that the title products possess good fungicidal activities.  相似文献   

4.
稀土与β-二酮及2-(2-吡啶)苯并咪唑三元配合物的研究   总被引:2,自引:0,他引:2  
As useful fluorescent reagent, rare earth complexes with β-diketones have been extensively studied. Four new rare earth (La, Eu) ternary complexes with β-diketones, (benzoylacetone (Hbza), 2-thenoyltrifluoroacetone, (HTTA)) and organic base (2-(2-pyridyl) benzimidazole, (Hpbi)) have been synthesized and characterized by elemental analysis, IR, NMR. The general formulae of these complexes are [Ln(bza)3(Hpbi)] and[Ln(TTA)3(Hpbi)]. The effects of coordinated base on UV, especially on fluorescent properties of the complexes were discussed. The results showed that the dehydro-Hpbi, pbi-, strongly enhances the fluorescence of the complexes.  相似文献   

5.
Treatment of lithio derivativ e of novel PEG-supported a-phenylselenopropionate with aldehydes, followed by oxidation-elimination with 30% hydrogen peroxide, formed Baylis-Hillman products, which were then reacted with sodium arylsulfinate. The resulting sulfonylated products were cleaved from the PEG efficiently affording methyl (2Z)-2-arylsulfonylmethyl-2-alkenoates in good yields and high purities.  相似文献   

6.
Optically active polyurethane was synthesized by the polyaddition of (2R, 3R)-(+)-diethyl L-tartrate (DET), 4,4'-diphenylmethane diisocyanate (MDI) and polyethylene glycol (PEG) with variousmolecular weights at 60℃in DMSO. The polymers were characterized by specific rotation, DSC and ~1HNMR spectra.  相似文献   

7.
Li4Ti5O12溶胶-凝胶法合成及其机理研究   总被引:15,自引:0,他引:15  
The precursors of Li4Ti5O12 were prepared from tetrabutyl titanate and lithium acetate by sol-gel process. The Li4Ti5O12 samples were synthesized by calcining the gel precursors at 400~900 ℃ in air for 6~20 h. Its reaction mechanism was investigated by infrared spectroscopy(IR), thermogravimetry(TG) and X-ray diffraction(XRD). The effects of sinter-temperature, calcination-time and thermal-treatment for the products were discussed. The samples were characterized by X-ray diffraction(XRD), scanning electron microscopy(SEM). The results showed that the single-phase products were obtained by calcining the gel precursors at 800 ℃ in air for 20 h, the sinter-temperature was lower than that of solid-state method, the particles were narrowly distributed, well crystallized with a size range from 0.3μm to 0.5 μm.  相似文献   

8.
α-{3-[2-hydroxy-3-(N-methyl-N-hydroxyethylamino)propoxy]propyl}-ω-butylpolydimethylsiloxanes Ⅲ with various moleculax weights were prepared by epoxy addition of α-[3-(2,3-epoxy-propoxy)propyl]-ω-butylpolydimethylsiloxanes Ⅱ and Nmethylmonoethanolamine.At each step.the outcome compounds were characterized through FT-IR and NMR spectra,the results showed that each step was successfully carried out and objective products were achieved.  相似文献   

9.
Hydrolysis reaction of Fe(NO3)3 at a high temperature in the presence of urea as the homogeneous precipitant was studied. With the prepared ceramic filter balls loaded with α-Fe2O3 after high temperature calcination, the loading of α-Fe2O3 on the porous ceramic filter balls from Fe(NO3)3 solutions of different concentrations and mechanical stability of the loaded α-Fe2O3 were studied. The product was characterized using XRD and SEM. Adsorption experiments were conducted to evaluate the performance of the product in adsorbing NH3-N. It turned out that the specific surface area of the ceramic filter balls loaded with α-Fe2O3 had increased to 36.5387 m2/g from original 4.6127 m2/g. When the concentration of Fe(NO3)3 was 0.40 mol/L, the loading of α-Fe2O3 on the ceramic filter balls accounted for 8.4% of the total mass of the adsorbent and α-Fe2O3 was adsorbed on the filter balls very well. The adsorption isotherm of NH3-N on the ceramic filter ball adsorbent loaded with α-Fe2O3 was of Langmuir type. The saturated adsorption capacity was 3.33 mg/L, and the adsorption constant K was 0.1873. NH3-N was adsorbed by α-Fe2O3 more easily, which was a kind of specific adsorption.  相似文献   

10.
Phenylacetyl isothiocyanate (1) was reacted with benzoyl hydrazine (2a) in acetonitrile to give thiosemicarbazide derivative 3 which was cyclized by polyphosphoric acid to give 1,2,4-triazoline-5-thione derivative 4. Treatment of 1 with thiosemicarbazide (2b) yielded another 1,2,4-triazoline-5-thione derivative 5. Similar treatment of 1 with phenyl hydrazine (2c) in acetonitrile gave a differently substituted 1,2,4-triazoline-5-thione derivative 6 in one pot-reaction. On the other hand, when the reaction was carried out in acetone, a mixture of 6 and thiadiazolidine derivative 7 was obtained. However, reaction of 1 with hydrazine hydrate (2d) gave hydrazine derivative 8. Reaction of isothiocyanate 1 with anthranilic acid (9) gave benzo[d][1,3,6]oxazin-1-one derivative 10. Treatment of 1 with 2-aminothiophenol (11a), 2-aminophenol (11b) or o-phenylenediamine (11c) produced benzothiazole derivative 12a, benzoxazole derivative 12b and benzimidazole derivative 12c, respectively. The structures of all the products were confirmed by micro-analytical and spectral data.  相似文献   

11.
La2(CO3)3 nanowires were prepared in the nonionic surfactant microemulsion(Triton X-100/cyclohexane/water)system. Transmission electron microscopy (TEM) and selected area electronic diffraction (SAED) were used to characterize the shape and size of the products. The results showed that the pH value and concentration of mother solution, temperature and aging time all could affect the morphology and size of the La2(CO3)3 nanowires. The lengths of the nanowires were more than 10 μm and the diameters were in the range of 30~200 nm.  相似文献   

12.
方志刚  胡红智 《无机化学学报》2006,22(12):2222-2228
With the level of B3LYP/Lanl2dz of density functional theory and advisable adsorption models designed, the adsorption properties of the most stable cluster of Ni2Fe2P were calculated, and four stable configurations with the adsorption of hydrogen were gained. The geometries and HOMO contributions of 3d orbital of metal atoms and energy level properties of adsorption configurations were concerned and their Infrared Spectrum were simulated and predicted. The bond lengths and bond orders and vibration frequencies concerned synthetically, the adsorption mechanisms of hydrogen molecular on amorphous alloys Ni40Fe40P20 surfaces were discussed in the microcosmic aspect. The hydrogen molecules adsorbing on the clusters were dissociated. In the clusters′ Infrared Spectrums of hydrogen adsorption, there were the vibration peaks with the frequency less than 500 cm-1 caused by metal atoms and other vibration peaks with the frequency more than 500 cm-1 caused by hydrogen atoms. Compared with the energy level DOS of the clusters before and after adsorption, it was found, that the new adsorption activity sites generated after the adsorption of hydrogen, as well as easy way for metal atoms providing electrons and participating subsequence reactions were gained.  相似文献   

13.
以(S)-2-氨基丙醇为手性源与α-溴-3-氯苯丙酮反应, (R)-2-氨基丙醇为手性源与6-甲氧基-2-(2-溴丙酰基)萘反应, 分别合成了手性纯化合物(2R,3R,5S)-3,5-二甲基-2-(3-氯苯基)-2-吗啉醇盐酸盐(4a)和(2S,3S,5R)-3,5-二甲基-2-(6-甲氧基-2-萘基)-2-吗啉醇盐酸盐(4b), 利用X射线单晶衍射仪测定了两化合物的晶体结构和两化合物的空间结构, 并初步分析两化合物空间结构, 化合物4a晶体属正交晶系, 空间群为P21212, 晶胞参数为: a=0.8718(2) nm, b=0.7883(2) nm, c=2.0247(6) nm, Z=4, V=1.3915(7) nm3, Dc=1.328 g/cm3, F(000)=584, R1=0.0399, wR2=0.0797, S=1.042. 化合物4b晶体属正交晶系, 空间群为P212121, 晶胞参数为: a=0.71035 (9) nm, b=0.77703(10) nm, c=2.9820(4) nm, Z=4, V=1.6318(4) nm3, Dc=1.318 g/cm3, F(000)=688, R1=0.0520, wR2=0.1108, S=0.994.  相似文献   

14.
LiMn2O4的湿法合成及锰的光度法测定研究   总被引:2,自引:0,他引:2  
The LiMn2O4 spinel was prepared by wet method using Li2CO3, Mn(CH3COO)2·4H2O and CO2 as raw ma-terials. The products were measured by TG/DTA, XRD, IR. The results Showed that the sample calcined at 800℃ for 10h was well crystallized monophase product. The contents of Mn(Ⅲ) and Mn(Ⅳ) of LiMn2O4 spinel were determined simultaneously by spectrophotometric analysis with pyrophosphoric acid.  相似文献   

15.
Highly optically active 4-substituted-2(5H)-furanones 6a-6j were obtained in good yields with de≥98% by the tandem Michael addition/elimination reaction of chiral 3-bromo-2(SH)-furanone (4a), which was conveniently prepared starting from 2-furaldehyde under mild conditions. The products were identified on the basis of their satisfactory elemental analysis and spectroscopic data of IR, UV, ^1H NMR, ^13C NMR and mass spectra. The stereochemistry and absolute configuration of this type of compounds were established by the X-ray crystallographic study. The reaction provided a short and efficient synthesis of the interesting highly optically active 4-subsdtuted-2(5H)-furanones containing an active pyrimidine and a purine base group.  相似文献   

16.
In an alkaline 2-propanol solution with 5, 10,15,20-tetra (4-methoxyl phenyl) porphyrin iron chloride (TOMPPFeCl) as a catalyst and oxygen as a cheap green oxidant, 2-naphthol was conversed to 2-hydroxy-1 ,4-naphthoquinone(HNQ) with a yield of 62. 17% and a selectivity of 100%, and the conversion number of TMOPPFeCl catalyst was 8.32/min. The catalytic oxidation products were characterized by means of UVVis, IR, GC-MS, ^1H NMR and melting point determination. In this catalytic oxidation, the catalytic activity of TMOPPFeCl was researched in detail and the reacting conditions were optimized. A possible reaction mechanism is summarized based on in situ EPR determination.  相似文献   

17.
Four different hematite (α-Fe2O3) nanopowders with various morphologies have been synthesized in the presence of surfactant (HPC) via hydrothermal route at 180 ℃, using four kinds of iron salts, Fe2(SO4)3, FeC2O4, FeSO4 and (NH4)3Fe(C2O4)3, as precursor materials. The products were characterized by means of X-ray diffraction (XRD), transmission electron micrograph (TEM), Fourier transform infrared spectroscopy (FTIR) and magnetization measurements. The hysteresis measurements show that the products exhibit weak ferromagnetic property at room temperature. It is concluded that the different precursor materials and the presence of the surfactant are important factors that exert significant effects on the morphologies and magnetic properties of the products.  相似文献   

18.
纳米二氧化钛粉末的溶胶-凝胶法合成及晶相转化   总被引:25,自引:0,他引:25  
Nanosized TiO2 powder with anatase and rutile structures was synthesized by a sol-gel method using TiCl4 ethanol solution as a precursor.The grain size of TiO2 powder was about 63nm after the precursor was calcined at 600℃ for 2 hours .The experimental techniques of XRD,TEM and Particle Distribution were used to characterize the synthesized specimens. Various special effects were investigated for their contribution to crystal structure and the size of TiO2 powder .The formation of anatase as well as the rutile phase of TiO2 was indicted from the XRD when the reaction temperature was above 30℃ and when the sol was irradiated by infrared rays .However, an anatase TiO2 powder formed after the heat treatment of the dried gel in a temperature range from 300℃ to 500℃.Under the vacuum drying and with the calcined time below 3hours ,the anatase phase was gained .As well as with the increase of gelatinizing time, the anatase TiO2 powder was obtained.  相似文献   

19.
纳米SnO2的非水溶剂溶胶-凝胶法制备与表征   总被引:2,自引:0,他引:2  
Nanometer SnO2 powders were successfully prepared by non-hydrolytic sol-gel approach combined with heat treatments using tin tetrachloride as starting material and ethylene glycol as solvent. The reaction mechanism of the sol-gel process is proposed. Results indicate that the -OHCH2CH2OH- prevent Cl- ion from accessing to tin Sn4+ due to steric effect, and hence increaseing the stability of the sol solution. Ethylene glycol functions not only as a complextion agent to form a polymer network but also as a “spacer” to modulate the distance between metal ions, preventing metal oxide particles from aggregation during desiccation of the sol. The effects of heat treatments on the evolution of structure and morphology of nanosized SnO2 powders were studied. The powders with narrow size distribution around 15~20 nm could be obtained at 500 ℃ for 4 h.  相似文献   

20.
New quinolone derivatives of 7-[(2S, 4R)-2-aminomethyl-4-hydroxypyrrolidin-l-yl] quinolone-3-carboxylic acids were synthesized by condensation of 7-halo substituted quinolone-3-carboxylic acids with (2S, 4R)-2-aminomethyl-4-hydroxypyrrolidine. These compounds were characterized by FAB-MS and IH NMR.  相似文献   

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