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1.
New stable silayl cationic surfactants have been studied for the destruction of toxic organophosphorus pesticides. Hexadecyl,
dodecyl trimethyl silane ammonium chloride or iodide surfactants were synthesized and evaluated in the degradation of pesticides
such as Diazinon, Malathion or Chlorpyrifos. The hydrolytic efficiency of each surfactant was tested by measuring the kinetics
of model substrates cleavage under a pseudo-first order reaction. The iodo silayl based surfactants showed more destructive
power than the chloro derivatives. Meanwhile, the hexadecyl moiety showed more effective pesticide degradation than the corresponding
dodecyl moiety.
相似文献
Abdelfattah M. Badawi (Corresponding author)Email: |
Sahar M. AhmedEmail: |
2.
Yurong Jiang Zhigang Xu Jimei Luan Pingqin Liu Weihong Qiao Zongshi Li 《Journal of surfactants and detergents》2007,10(3):131-136
Three unsymmetrical bolaform surfactants with different aromatic rings and a ω-carboxyalkyl chain were synthesized and their
molecular structures were characterized by ESI–MS and 1H NMR. The percentages of conversion of alkylation were judged by the iodine value measurements and the effect of reaction
temperature on sulfonate content of synthesized products has also been discussed.
相似文献
Yurong JiangEmail: |
3.
Xiao-min Luo Long-fang Ren Xiao-lei Zhang Tao-tao Qiang 《Journal of surfactants and detergents》2009,12(1):1-5
A SO4
2−/ZrO2 super acid was prepared and the effect of different kinds of catalysts on the esterification reaction reviewed. The results
showed that the SO4
2−/ZrO2 super acid had higher catalytic activity and reactive selectivity in the synthesis of oleic acid polyglycol ester. Under
optimum conditions the product was a monoester and the rate of production was more than 90%. The reaction product was characterized.
相似文献
Tao-tao QiangEmail: |
4.
M. S. L. Karuna B. L. A. P. Devi P. S. S. Prasad R. B. N. Prasad 《Journal of surfactants and detergents》2009,12(2):117-123
1-Alkylamino-3-alkyloxy-2-propanols, V (a–g) and N,N-di-(2-hydroxy-3-alkyloxy propyl) alkylamines, VI (a–g) were prepared with the same chain length both for alkyl amino and alkyloxy groups by condensation of alkyl glycidyl ethers
with long chain alkylamines by employing thermal and microwave-assisted methods. All the products were characterized by 1H-NMR, IR and fast atom bombardment mass spectrometry studies. These compounds were further sulfated and evaluated as their
sodium salts for surfactant properties namely surface tension, critical micelle concentration, emulsifying property, wetting,
foaming power and calcium tolerance. Sulfated 1-dodecylamino-3-dodecyloxy-2-propanol, VII c and sulfated N,N-di-(2-hydroxy-3-dodecyloxy propyl) dodecylamine, VIII c were found to exhibit superior surfactant properties among the respective series of monomers and dimers.
相似文献
R. B. N. PrasadEmail: |
5.
Microwave-Assisted Synthesis and Properties of a Novel Cationic Gemini Surfactant with the Hydrophenanthrene Structure 总被引:3,自引:0,他引:3
Weihong Jia Xiaoping Rao Zhanqian Song Shibin Shang 《Journal of surfactants and detergents》2009,12(3):261-267
A novel cationic gemini surfactant with the hydrophenanthrene structure has been synthesized from dehydroabietic acid by use
of conventional thermal conditions and microwave irradiation. Its structure was confirmed by IR, 1H NMR, and 13C NMR spectroscopy. It was found that microwave-assisted synthesis is an efficient means of preparation of this cationic gemini
surfactant, with shorter reaction times and higher yields. The title compound had high surface activity. The CMC was 3.1 × 10−5 mol L−1, γ
CMC was 26.3 mN m−1, and emulsifying power (with benzene) reached five days. Comparison of this gemini surfactant and its monomeric counterpart
proved the gemini surfactant was more surface active.
相似文献
Zhanqian SongEmail: |
6.
Toon Verstraelen Bartłomiej M. Szyja David Lesthaeghe Reinout Declerck Veronique Van Speybroeck Michel Waroquier Antonius P. J. Jansen Alexander Aerts Lana R. A. Follens Johan A. Martens Christine E. A. Kirschhock Rutger A. van Santen 《Topics in Catalysis》2009,52(9):1261-1271
Zeolite synthesis is driven by structure-directing agents, such as tetrapropyl ammonium ions (TPA+) for Silicalite-1 and ZSM-5. However, the guiding role of these organic templates in the complex assembly to highly ordered
frameworks remains unclear, limiting the prospects for advanced material synthesis. In this work, both static ab initio and
dynamic classical modeling techniques are employed to provide insight into the interactions between TPA+ and Silicalite-1 precursors. We find that as soon as the typical straight 10-ring channel of Silicalite-1 or ZSM-5 is formed
from smaller oligomers, the TPA+ template is partially squeezed out of the resulting cavity. Partial retention of the template in the cavity is, however,
indispensable to prevent collapse of the channel and subsequent hydrolysis.
相似文献
Rutger A. van Santen (Corresponding author)Email: |
7.
Brahim Bettayeb Caroline Descôteaux François Benoit Camille Chapados Gervais Bérubé 《Journal of surfactants and detergents》2009,12(3):237-247
Fourteen pure β-aminopropionic acid amphoteric surfactants were synthesized from methyl acrylate using primary amines. The
synthesis was done in two steps. First, Michael addition of a primary amine to methyl acrylate gave two separable addition
products. Second, because the resulting esters gave, by the classical saponification procedure, undesired retro-Michael products,
they were treated with sodium trimethylsilanolate to give the corresponding pure anhydrous acid salt under mild non-aqueous
reaction conditions. Two types of amphoteric surfactants were obtained: the monocarboxylate and the dicarboxylate series.
The pure surfactants were characterized by IR, 1H NMR, and 13C NMR spectroscopy. The surfactant critical micelle concentrations were evaluated. From these the Gibbs free energy of micellizations
[∆G(–CH2–)mic] were calculated. These are related to the methylene units that contribute an average of −1.0 (±0.3) kJ mol−1 for both the monocarboxylate and the dicarboxylate series.
相似文献
Gervais BérubéEmail: |
8.
H. A. A. Rasoul G. W. Rinke J. P. Wiruth A. E. Trevino B. E. Mote M. A. Langer D. L. Trumbo 《Journal of Coatings Technology and Research》2008,5(1):113-115
Low molecular weight resins containing relatively high levels of acrylic acid were converted to oxidatively curable materials
by reacting the carboxylic acid groups with oxazoline functional alkenes. The oxazolines were obtained by reacting fatty acid
with 2-amino-2-methyl-1-propanol. The oxazolines were then reacted with the acrylic resins at elevated temperature. Relatively
high yields of the desired reaction products were obtained in relatively short reaction times. The resulting resins were formulated
into aqueous coatings and films were made over metal substrates. The films were cured oxidatively and evaluated for property
development. The films had good general solvent resistance but poor resistance to dilute sodium hydroxide.
相似文献
D. L. TrumboEmail: |
9.
Charles N. Myer Christopher W. Allen 《Journal of Inorganic and Organometallic Polymers and Materials》2007,17(1):143-148
The mixed substituent chlorocyclophosphazene monomers 2,2′-N3P3Cl4[O(CH2)4OC(O)C(Me)CH2][C5H5FeC5H4CH2NMe](1) and 2,2′,4-N3P3Cl3[O(CH2)4OC(O)C(Me)CH2][C5H5FeC5 H4CH 2NMe]2 (2) undergo radical addition copolymerization with methylmethacrylate to produce a broad range of copolymers having pendant
cyclophosphazenes containing a ferrocenyl substitutent. In both bulk and solution copolymerization, the conversion decreased
with increasing amount of 1 in the monomer feed with no copolymer formation observed in co-monomer mixtures containing greater than 50% of 1. NMR studies of the copolymers show that the copolymer composition is the same as the monomer feed and that the triad tacticity
is constant throughout the series for 1 but an increase in syndiotactic triads is observed for 2. TGA studies indicate an increase in char yield with an increase in the phosphazene content of the copolymer.
相似文献
Christopher W. AllenEmail: |
10.
Seppo Kaltia Jorma Matikainen Maija Ala-Peijari Tapio Hase 《Journal of the American Oil Chemists' Society》2008,85(6):561-565
Pinolenic acid (5Z,9Z,12Z-octadecatrienoic acid, 1a), one of the most abundant trienoic fatty acids in nature, is very difficult to obtain in quantity in a pure state from the
highly complex mixture of unsaturated tall oil fatty acids. For this reason its chemistry has been little studied when compared
to linolenic or linoleic acids. A simple synthesis of esters of 1a and of 12Z,15Z-octadecadienoic acid 3 using the one pot double Wittig procedure is described here. The products of double Wittig reactions were purified by argentation
chromatography, and their structural purity was established by 1H-, 13C-NMR and 2D-NMR spectroscopies.
相似文献
Tapio HaseEmail: |
11.
Two series of quaternary cationic surfactant were synthesized by reaction of 8-hydroxyquinoline and 2-hydroxypyridine with
long chain alkyl halides (dodecyl, tetradecyl- and hexadecyl-bromide). Surface tension was measured in aqueous solution for
different concentrations at 25 °C. Various surface properties of the synthesized surfactants were evaluated, particularly
critical micelle concentration (CMC), efficiency (ΠCMC) as well as maximum surface excess (Γmax) and minimum surface area (A
min). Micellization and adsorption in liquid/air interfaces thermodynamics were investigated. The synthesized cationic surfactants
were evaluated for their biocidal activity. All compounds prepared showed good antibacterial and antifungal activities.
相似文献
Dina A. IsmailEmail: |
12.
Massimo Fabris Cindy Aquino Antony J. Ward Alvise Perosa Thomas Maschmeyer Maurizio Selva 《Topics in Catalysis》2009,52(3):315-321
In this contribution we describe the use of heterogeneous catalysts for the liquid-phase self-metathesis of 1-octene in supercritical
CO2. Our work aims at addressing the mass-transfer problems associated with such reaction systems. By coupling a heterogeneous
supported Re2O7 catalyst with the use of scCO2, the self-metathesis of 1-octene takes place by and large much more rapidly than in traditional solvent media, and furthermore,
by using scCO2 the overall efficiency and sustainability of the transformation can be improved.
相似文献
Maurizio Selva (Corresponding author)Email: |
13.
Daisuke Saio Toru Amaya Toshikazu Hirao 《Journal of Inorganic and Organometallic Polymers and Materials》2009,19(1):79-84
Polyaniline/Pd nanoparticles were synthesized via ligand exchange. Pre-prepared water soluble starch/Pd nanoparticles were
treated with polyaniline, and washed with water, leading to the small and well-dispersed polyaniline/Pd nanoparticles. The
redox state of polyaniline was preserved during the ligand exchange reaction.
相似文献
Toshikazu HiraoEmail: |
14.
Mohammadreza Khanmohammadi Mohammadjavad Hosseinnia Kojidi Amir Bagheri Garmarudi Ahmad Ashuri Majid Soleymani 《Journal of surfactants and detergents》2009,12(1):37-41
An analytical procedure was developed to monitor the batch reaction of coconut oil and diethanolamine which also would determine
the cocodiethanolamide (CDEA) content of the final product. The method was based on attenuated total reflectance Fourier transform
infrared spectrometry utilizing partial least squares regression. The calibration was modeled in the 1,781–1,714 and 1,658–1,639 cm−1 spectral regions for coconut oil and CDEA respectively. The models were then applied to predict the amidation process yield
and to monitor the in situ kinetics of reactions between coconut oil and DEA. The root mean square error of prediction was
0.590 and 0.336 for coconut oil and CDEA respectively. The proposed method can also be successfully applied to the determination
of purity in commercial grade CDEA samples and would give reliable results in comparison with the potentiometric titration
reference method.
相似文献
Mohammadreza KhanmohammadiEmail: |
15.
Assessment of UV-permeability in nano-ZnO filled coatings via high throughput experimentation 总被引:1,自引:0,他引:1
Michael S. Lowry David R. Hubble Amy L. Wressell Menas S. Vratsanos Frank R. Pepe Charles R. Hegedus 《Journal of Coatings Technology and Research》2008,5(2):233-239
The degree of UV protection afforded by nano-ZnO in a polyurethane/acrylic clear topcoat was investigated. The influence of
nano-ZnO concentration and dry film thickness on the optical properties (e.g., UV permeability and visible transmittance)
of the coating was probed using a library of 28 samples that were prepared by high throughput techniques. A model for predicting
the UV permeability of nano-ZnO filled coatings was developed and the nano-ZnO loading condition required to block >99% UV
radiation was determined to be 2.0 g/m2. This model can be used to assist in the development of coatings and other polymeric systems embedded with nano-ZnO to protect
the coating and underlying materials (i.e., substrate) from UV degradation.
相似文献
Charles R. HegedusEmail: |
16.
A. M. Badawi M. A. Mekawi A. S. Mohamed M. Z. Mohamed M. M. Khowdairy 《Journal of surfactants and detergents》2007,10(4):243-255
In this study, steps were taken toward the development of bactericidal and fungicidal synthetic cationic surfactants by reacting
decyl, dodecyl or tetradecyl amine with acetic or hydrochloric acid to produce a series of amine salts which consequently
converted to copper or cobalt cationic complexes via complexing the first series compounds with copper (II) or cobalt (II)
ions. Surface properties such as interfacial tension and emulsifying power of these surfactants were investigated. The surface
parameters including critical micelle concentration (CMC), maximum surface excess (Γmax) and minimum surface area (A
min) were studied. Free energy of micellization (ΔG°mic) and adsorption (ΔG°ads) were calculated. The antimicrobial activity was determined via the inhibition zone diameter of the prepared compounds, which
measured against five strains of a representative group of microorganisms. FTIR spectra, elemental analysis and H1 NMR spectrum were performed to confirm compound structure and purity.
相似文献
M. Z. MohamedEmail: |
17.
Abdolraouf Samadi-Maybodi Naser Goudarzi Christopher W. Kirby Yining Huang 《Journal of surfactants and detergents》2008,11(1):49-54
Silicate anions were studied using 29Si NMR to investigate the structure-directing effect of a surfactant (sodium dodecylsulfate-SDS) on the distribution of silicate
species present in alkaline silicate solutions. The distribution of the anions in the presence of polyelectrolytes was also
investigated by 29Si NMR through the use of different bases including tetramethyl ammonium hydroxide (TMAOH) and sodium hydroxide (NaOH). Both
SDS and the polyelectrolytic solutions were shown to stabilize low molecular weight silicate species and thus inhibit polymerization.
相似文献
Abdolraouf Samadi-MaybodiEmail: |
18.
The properties of surfactin-C16 aqueous solution in the presence of Na+ ions, produced by Bacillus subtilis, were studied by the fluorescence method. The critical micelle concentration (CMC) of surfactin-C16 was measured as 24.7 μM in 0.05 M Tris buffer (pH 8.5–8.6). With an increase in Na+ concentration, the CMC value and micropolarity of surfactin-C16 decreased while the microviscosity increased, which means that the addition of Na+ improves the surface activity and enhances the micellization of the surfactin-C16 in solution. The preliminary aggregation number (N) was obtained by the steady-state fluorescence method.
相似文献
Bo-Zhong MuEmail: |
19.
This paper describes an efficient method for the synthesis of long chain dialkyldiamido imidazolines by the reaction of diethylenetriamine
and several fatty acids under non-solvent microwave irradiation using calcium oxide as support This synthesis required much
less time in comparison to conventional thermal condensation and is carried out in an open vessel and the products obtained
by this method were found to be in good yields and of high purity. Fatty imidazolines were then quaternized by using dimethyl
sulfate as a quaternizing agent and isopropanol as a solvent, to produce cationic imidazolinium salts which were evaluated
for yield and cationic content. The instrumental techniques, viz. FT-IR and 1H NMR verified the formation of imidazolines and its subsequent quaternization. This method produced imidazolines in the very
low time of 5–10 min and gave a yield of 89–91% as compared to a very long time of 8–10 h and a lower yield of 75–80% by the
conventional thermal condensation method.
相似文献
Divya BajpaiEmail: Email: |
20.
Bevin C. Daglen David R. Tyler 《Journal of Inorganic and Organometallic Polymers and Materials》2009,19(1):91-97
The effects of time-dependent morphology changes on the photochemical degradation efficiencies of polymers were investigated
using the segmented polyurethane 1. A segmented polyurethane was chosen for this study because segmented polyurethanes have distinct hard (crystalline) and
soft (amorphous) morphologies in the solid-state. It is known that, as these polymers cure, the hard and soft domains expand
in the days and weeks following preparation. Experiments showed that the quantum yields for degradation of thin films of polymer
1 decreased over a period of about 30 days following preparation of the polymer films. Infrared spectroscopy showed an increase
in crystallinity in the polymer during this curing period. These results are consistent with the hypothesis that the rate
of photodegradation in polymer systems is controlled by the separation rate of the photogenerated radical pair relative to
the rate of radical-radical recombination (Scheme 3). An important factor that controls the ratio of these two rates is the crystallinity of the polymer; an increase in crystallinity
favors the radical-radical recombination reaction. The effect of tensile stress on photodegradation efficiencies was also
studied. Two samples of the same polymer, one more crystalline than the other, were examined. The quantum yields for degradation
of the more crystalline sample were less affected by tensile stress than the less crystalline sample. Tensile stress is known
to order polymer chains and the results are again interpreted as being consistent with the idea that crystallinity is an important
factor in controlling the efficiency of polymer photodegradation.
相似文献
David R. TylerEmail: |