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1.
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.
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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
2.
Surface modification of CaCO3 filler and its characterization using inverse gas chromatography (IGC)
A CaCO3 filler was treated by generally used coupling agents and a special one — ethylene-octene copolymer (POE)-g-maleic anhydride (MAH). Fourier transform infrared spectroscopy (FTIR) results show that the special coupling agent POE-g-MAH, in a chemical reaction with CaCO3, can produce an interfacial layer stronger than simple physical adhesion attained with usual coupling agents. Inverse gas
chromatography (IGC) was used to investigate the surface free energy of CaCO3 after surface modification and to optimize the monolayer content of coupling agents. Based on the IGC results, it can be
deduced that the monolayer cover is around 1.9% for CaCO3 treated with a titanate coupling agent. Scanning electron microscope (SEM) observation results show that the separated morphology
existed in the ternary composites containing CaCO3 after surface treatment with coupling agents, whereas the core-shell morphology was obtained in the ternary composites with
POE-g-MAH. The encapsulation of the CaCO3 filler treated with POE-g-MAH was caused by the strong chemical reaction between the elastomer and CaCO3 particles.
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Translated from Journal of Northwestern Polytechnical University, 2007, 25(2): 274–278 [译自: 西北工业大学学报] 相似文献
3.
Huixue Ren Yanzhao Yang Jimao Lin Yinshan Qi Yeqing Zhang 《Frontiers of Chemistry in China》2008,3(2):152-156
A new synthetic method for 5-bromo-3-sec-butyl-6-methyluracil (Bromacil) using 2-bromobutane and urea as starting materials is described. The synthesis involved condensation,
cyclization and bromination with a total yield of 60%. The structure of Bromacil was determined by 1H NMR, 13C NMR and IR spectroscopy.
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Translated from Journal of Shandong University (Natural Science Edition), 2007, 42(7): 9–12 [译自: 山东大学学报(自然科学版)] 相似文献
4.
A series of Cp2Ti(SB)Cl complexes, whereSB is the anion of bidentate Schiff bases derived from salicylaldehyde and different primary aminesviz o-anisidine,m-anisidine,o-phenetidine,o-chloroaniline,m-chloroaniline,m-nitroaniline, α-naphthylamine and benzylamine, have been synthesised by the reaction of dichloro-bis(cyclopentadienyl) titanium(IV),
Cp2TiCl2, and bidentate Schiff base (sbh) in a 1:1 molar ratio in refluxingthf in the presence of triethylamine. The new derivatives have been characterised on the basis of their elemental analyses, conductance
measurements and spectral (IR,1Hnmr and electronic) studies 相似文献
5.
The poly(o-anisidine)–sulfuric acid–glucose oxidase (POA–H2SO4–GOx) electrode has been investigated in the present work. Platinum electrode was used for the synthesis of poly (o-anisidine)–sulfuric acid (POA–H2SO4) film using galvanostatic method with 0.2 M o-anisidine, 1.0 M H2SO4 solution, 1.0 pH and 2 mA/cm2 applied current density. The synthesized film was characterized using electrochemical technique, conductivity measurement,
UV–visible spectroscopy, Fourier transform infrared spectroscopy, and scanning electron microscopy. GOX was immobilized on synthesized POA–H2SO4 film by cross-linking via glutaraldehyde in phosphate and acetate buffer. The Michaelis–Menten constant (
K\textm¢K_{\text{m}}^\prime ) was determined for the immobilized enzyme. The glucose oxidase electrode shows the maximum current response at pH 5.5 and
potential 0.6 V. The sensitivity of POA–H2SO4–GOX electrode in phosphate and acetate buffer has been recorded. The results of this study reveal that the phosphate buffer gives
fast response as compared to acetate buffer in amperometric measurements. 相似文献
6.
By irradiation in methanol at 3000Å, aniline and o-anisidine were produced from benzo-triazole and N-methylaniline and N-methyl-o-anisidine were produced from N-methylbenzotriazole. Carbazole was the only product detected from similar treatment of N-phenylbenzotriazole. Linear naphthotriazole was photolytically transformed into β-naphthylamine but a methoxy derivative could not be found. Angular naphthotriazole gave no identifiable photolytic product. u-Triazolo[1,5-α]pyridine underwent photolysis in methanol to give α-picoline, α-picolylmethyl ether and α-picolylmethanol in low yield. A similar photolysis in acetic acid afforded α-pyridylmethyl acetate. The mechanisms for the formations of products are discussed. 相似文献
7.
Kinetics of thermal decomposition of CeO2 nanocrystalline precursor prepared by precipitation method
Xiaolan Song Xi He Haiping Yang Dayu Xu Nan Jiang Guanzhou Qiu 《Frontiers of Chemistry in China》2008,3(2):182-185
The thermal decomposition of CeO2 nanocrystalline precursor prepared by chemical precipitation method was investigated using thermo-gravimetric/differential
scanning calorimetry (TG/DSC) and X-ray powder diffraction (XRD). In particular, the differential thermal analysis curves
for the decomposition of CeO2 nanocrystalline precursor were measured at different heating rates in air by a thermal analyzer (NETZSCH STA 449C, Germany).
The kinetic parameters of the thermal decomposition of CeO2 nanocrystalline precursor were calculated using the Kissinger method and the Coats-Redfern method. Results show that the
apparent active energy E of the reaction is 105.51 kJ/mol, the frequency factor lnA is 3.602 and the reaction order n is 2. This thermal decomposition process can be described by the anti-Jander equation and a three-dimensional diffusion mechanism.
Tanslated from Journal of Central South University (Science and Technology), 2007, 38(3): 428–432 [译自: 中南大学学报(自然科学版] 相似文献
8.
M. L. Keshtov A. L. Rusanov N. M. Belomoina A. K. Mikitaev 《Russian Chemical Bulletin》1997,46(10):1794-1796
Bis[p-(phenylethynyl)phenyl]hetarylenes were synthesized in high yields by an improved method using cross-coupling between phenylacetylene
and 4,4′-dibromobenzil followed by condensation of the 4,4′-di(phenylethynyl)benzil obtained with eithero-phenylenediamine and 3,4-diaminobenzoic acid or with benzaldehyde andp-nitrobenzaldehyde in the presence of ammonium acetate.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1889–1890, October, 1997. 相似文献
9.
E. V. Ilyakina O. G. Mishchenko A. I. Poddel’skii S. V. Maslennikov I. V. Spirina 《Russian Journal of General Chemistry》2009,79(7):1483-1486
Photolysis of [4-(2-methyl-5-tert-butyl-cyclohexadiene-1,5-dion-3,4-yl)-3-methyl-6-t-butyl-catecholato] triphenylantimony(V) in toluene by irradiation with
the light of wavelength 546 nm leads to excitation of the molecule of parent compound which reacts with a molecule of Ph3SbCatQ
affording 4,4′-di-(3-methyl-6-tert-butyl-o-benzoquinone) and 4,4′-di[(3-methyl-6-tert-butyl-catecholato)triphenylantimony(V)]. The formed compounds react with each other returning the system into the initial
state. Action of light of wavelength 313 and 405 nm on the initial reaction mixture leads to the formation of carbon monoxide,
Ph3SbCatCatSbPh3 and the products of photolytic transformation of 4,4′-di(3-methyl-6-tert-butyl-o-benzoquinone). 相似文献
10.
Condensation of o-tosylaminobenzaldehyde with γ-aminobutyric, 4-aminophenylthioacetic, and p-aminobenzoic acids and β-alanine gave 6,12-epimino-5,11-ditosyl-5,6,11,12-tetrahydrodibenzo[b, f]-1,5-diazocines with carboxyl-containing substituents at the bridging N atoms. The structures of three products were examined by X-ray diffraction analysis. Condensation of o-mesylaminobenzaldehyde (prepared by the McFadyen-Stevens reaction) with NH4OAc and primary amines afforded 6,12-epimino-5,11-dimesyl-5,6,11,12-tetrahydrodibenzo[b, f]-1,5-diazocine derivatives.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2165–2171, October, 2004. 相似文献
11.
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.
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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
12.
An Efficient and Convenient Synthesis of 2-Thio[1,2,4]triazolo[1,5-c]quinazoline and its Derivatives
Alexandr V. Karpenko Sergey I. Kovalenko Svetlana V. Shishkina Oleg V. Shishkin 《Monatshefte für Chemie / Chemical Monthly》2006,137(12):1543-1549
Summary. 4-Hydrazinoquinazoline with carbon disulfide underwent a recyclization reaction. The title compound 2-thio[1,2,4]triazolo[1,5-c]quinazoline was obtained after treatment of 4-hydrazinoquinazoline with potassium ethylxanthogenate via a facile in situ Dimroth-like rearrangement of the expected [4,3-c] system. Its structure was established by X-ray diffraction study and confirmed by an independent synthesis, starting from
o-aminobenzonitrile. 相似文献
13.
Xiaofeng Zhang Shen Lin Xinqing Chen Jiebo Chen Liuyi Yang Minghong Luo 《Frontiers of Chemistry in China》2007,2(4):419-421
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.
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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
14.
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.
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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
15.
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.
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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
16.
Yue Situ Jianfeng Hu Hong Huang Heqing Fu Hanwei Zeng Huanqin Chen 《Frontiers of Chemistry in China》2008,3(2):235-241
A novel epoxidized soybean oil (ESO) internally toughened phenolic resin(ESO-IT-PR) with both good toughness and excellent
thermal stability was prepared as the matrix resin of copper clad laminate (CCL). FTIR was adopted to investigate the molecular
structure of modified phenolic resins and SEM was used to observe the micro morphology of their impacted intersections. The
properties of CCLs prepared with these modified phenolic resins were studied to determine the optimal process and investigate
the toughening mechanism. The main modifying mechanism is the etherification reaction between phenol hydroxyl and ESO catalyzed
by triethanolamine and the chain extension polymerization between ESO and multi-amine gives the long-chain ESO epoxy grafting
on the phenolic resin prepolymer. when the ESO content is 30% and the curing agent content is 7%, the ESO toughened phenolic
resin possesses optimal performance. The flexible ESO epoxy shows significant toughening effect and it crosslinks with the
phenolic resin to form an internally toughened network, which is the key factor for improving the solderleaching resistance
of CCL prepared with this modified phenolic resin.
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Translated from Journal of South China University of Technology (Natural Science Edition), 2007, 35(7): 99–104 [译自: 华南理工大学学报(自然科学版)] 相似文献
17.
Mohamed Hilmy Elnagdi Mohamed Riffat Hamza Elmoghayar Ezzat Mohamed Kandeel Mohamed Kamal Ahmed Ibrahim 《Journal of heterocyclic chemistry》1977,14(2):227-230
3-Phenylpyrazole-5-(liazonium chloride ( 1 ) couples with α-chloro derivatives of acetylacetone, ethyl acetoacetate and aceto-o-anisidine to yield the corresponding pyrazole-5-yl hydrazonyl chloride derivatives 2a-c . Compounds 2a,b were cyclised to yield either the pyrazolo[1,5-c]-1,2,4-triazole derivatives 3a,b or the pyrazolo[1,5-c]-as-triazines 4a,b depending on the applied reaction conditions. Compound 2c cyclised only into 3c under different cyclization conditions. The pyrazolo[1,5-c]-as-triazine derivatives 4c-e could be prepared via condensation of 2a with potassium cyanide. Compound 2d reacted with aromatic thioles and with sodium benzene-sulphonate to yield the pyrazolo[1,5-c]-as-triazine derivatives 6a-d . Compound 1 reacted with activated double bond systems to yield pyrazolo[1,5-c]-as-triazines 8a,b and 9 . 相似文献
18.
Lingang Li Yu Tang Yuanming Zhang Jun Yang Biying Du 《Frontiers of Chemistry in China》2008,3(1):76-80
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.
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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
19.
Peng Ping Wenshou Wang Peibiao Zhang Xuesi Chen Xiabin Jing 《Frontiers of Chemistry in China》2007,2(4):331-336
A series of segmented poly(L-lactide)-polyurethanes (PLA-PUs) were synthesized by a two-step method, with oligo-poly(L-lactide) (PLA) as the soft segments and the reaction product of 2,4-toluene diisocyanate (TDI) and ethylene glycol (EG) as
the hard segments. The shape-memory properties and biocompatibility of PLA-PUs were examined. The 50% compressed PLA-PUs could
recover almost 100% to their original shape within 10°C from the lowest recovery temperature (22°C–37°C). In the recovery
process the PLA-PU showed a maximum contracting stress in the range of 1.5–4 MPa. Cell incubation experiments show that PLA-PU
has biocompatibility comparable to that of pure PLA. Therefore, this kind of polyurethane can be used for implanted medical
devices with shape memory requirements.
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Translated from Chemical Journal of Chinese Universities, 2007, 28(2): 371–375 [译自: 高等学校化学学报] 相似文献
20.
Porous copolymer-based cation exchanger for the off-line preconcentration of aromatic amines from water 总被引:1,自引:0,他引:1
Summary A weakly polar porous copolymer and the sulfonic acid cation exchanger based on this copolymer were tested as sorbents for
off-line preconcentration of aromatic amines from water. Minicolumns packed with the 1,4-di(methacryloyloxymethyl)naphthalene—divinylbenzene
copolymer and the cation exchanger were used for the solid-phase extraction of polar amines.
In order to study the sorption properties of these polymeric materials, the recoveries and breakthrough volumes ofp-aminophenol,o, m andp-phenylenediamine, aniline,o andp-anisidine,p-nitroaniline, ando-toluidine were determined. 相似文献