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1.
The original article to which this Erratum refers was published in Surface and Interface Analysis Vol. 39, No. 4, 2007, pages 317–323. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

2.
The original article to which this errtum refers was published in the International Journal of Quantum Chemistry Int J Quant Chem (2006)106(4) 795 .  相似文献   

3.
Amphiphilic polymer conetworks consisting of hydrophilic poly[2‐(dimethylamino)ethyl methacrylate], poly(N‐isopropylacrylamide), or poly(N,N‐dimethylacrylamide) and hydrophobic polyisobutylene chains were synthesized with a novel two‐step procedure. In the first step, a methacrylate‐multifunctional polyisobutylene crosslinker was prepared by the cationic copolymerization of isobutylene with 3‐isopropenyl‐α,α‐dimethylbenzyl isocyanate. In the second step, the methacrylate‐multifunctional polyisobutylene crosslinker, with a number‐average molecular weight of 8200 and an average functionality of approximately 4 per chain, was copolymerized radically with 2‐(dimethylamino)ethyl methacrylate, N‐isopropylacrylamide, or N,N‐dimethylacrylamide into transparent amphiphilic conetworks containing 42–47 mol % hydrophilic monomer. The synthesized conetworks were characterized with solid‐state 13C NMR spectroscopy and differential scanning calorimetry. The amphiphilic nature of the conetworks was proved by swelling in both water and n‐heptane. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 6378–6384, 2006  相似文献   

4.
A new taxoid, 10-deacetyltaxezopidine G, and a previously reported compound (Taxezopidine G) have been isolated from the needles and young stems of Taxus baccata L. growing in Iran, and the structures were determined on the basis of spectroscopic data. These two compounds were not previously encountered in Taxus baccata L. species. Published in Khimiya Prirodnykh Soedinenii, No. 4, pp. 321–322, July–August, 2006.  相似文献   

5.
Novel, well‐defined fluorinated polystyrene was synthesized for the first time via the controlled radical polymerization of styrene through a relatively simple process and was characterized with 1H NMR, 19F NMR, and gel permeation chromatography. The surface properties of polystyrene and poly(acrylonitrile‐co‐butadiene‐co‐styrene) films were modified with the obtained polymers. X‐ray photoelectron spectroscopy measurements of the air‐side surface composition of the modified poly(acrylonitrile‐co‐butadiene‐co‐styrene) films showed that fluorine enriched the outermost surface, resulting in fantastic surface properties that came close to those of poly(tetrafluoroethylene). © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3853–3858, 2006  相似文献   

6.
The original article to which this erratum refers was published in the International Journal of Quantum Chemistry Int J Quantum Chem(2006)106(12)2536 .  相似文献   

7.
Methacrylamide (MAA) was grafted onto cotton cellulose. The influence of the reaction conditions on the grafting was studied in detail. Upon a chlorine bleach treatment, some of the amide groups in the grafted MAA side chains were transformed into stable acyclic N‐halamines; Hoffman‐type degradation was not observed. The resultant cotton celluloses provided a total kill of 108–109 CFU/mL for Escherichia coli (Gram‐negative bacteria), Staphylococcus aureus (Gram‐positive bacteria), and Candida tropicalis (fungi) in 3 min, 106–107 PFU/mL for the MS2 virus in 5 min, and 106–107 spores/mL for Bacillus subtilis in 4 h. The antibacterial, antifungal, antiviral, and antispore activities were both durable and rechargeable. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3588–3600, 2006  相似文献   

8.
A series of 2‐substituted benzimidazoles, benzoxazoles were synthesized by the condensation reactions of 1‐aryl‐4‐carboxy‐2‐pyrrolidinones and aromatic ortho‐diamines or ortho‐aminophenol. Alkylation of benzimidazoles with iodoalkanes led to 1‐aryl‐4‐(1‐alkyl‐1H‐benzimidazol‐2‐yl)‐2‐pyrrolidin‐ ones or 1,3‐dialkylbenzimidazolium iodides. N‐Subs‐ tituted γ‐amino acids were prepared by the hydrolysis of 1‐aryl‐4‐(1H‐benzimidazol‐2‐yl)‐2‐pyrrolidinones in sodium hydroxide solution, followed by treatment with acetic acid. The structure of the synthesized pro‐ ducts was investigated using IR and 1H, 13C NMR spectra, MM2 molecular mechanics, and AM1 semi‐ empirical quantum mechanical methods. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:47–56, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20171  相似文献   

9.
?When I wake up I row. When I was eighteen I wanted to be Morrissey. …?“ This and more about Benjamin G. Davis can be found on page 3900.

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10.
11.
Fredericon A, B, C, and D, Novel and Highly Functionalized Abietanoids from Leaf-Glands of Coleus fredericii From the leaf-glands of the title plant (fam. Labiatae) two novel, genuie spirocycloopropyl-coleons have been isolated and structurally characterized. Fredericon A (1) bears the unusal 1,1,2-tricarbonylcyclopropane substructure that renders the molecule very suseptible to nucleophile-promoted rearrangements. Biogenetically intriguing is the presence of a 3-acetoxypropyl side-chain in fredericon B ( 3 ). Its formation from the well known isopropyl group is explained by transformation of the latter into a spirocyclopropane, followed by a reductive opening of the cyclopropane and reducation of the aldehyde, MeOH addition to 1 , yields fredericon C ( 5 ), a derivative of 1H-phenanthro[3,2-b]pyran-7,12(2H,8H)-dione by two consecutive introlecular nucleophilic openings of the cyclopropane ring and the derived methoxy-oxirane. Similar methanolysis of a crude fraction of 1 , produced, in addition to 5 , the fredericon D, a novel derivative of 3H-phenanthro[3,2-b]pyran-2-(4H)-one( 6 ).  相似文献   

12.
Chemical compositions of essential oils (EO) from leaves and stems of Rhododendron adamsii, R. aureum, and R. dauricum were studied by GC/MS. The analysis demonstrated that the EO of these plants contained mainly mono-and diterpene hydrocarbons. A large amount of alkanes was also found in the EO of R. aureum. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 344–347, July–August, 2006.  相似文献   

13.
A conformational and electronic study on N‐acetyl‐L ‐isoleucine‐N‐methylamide was carried out. All side‐chain as well as backbone conformations were explored for this compound. Multidimensional conformational analysis predicts 81 structures in the case of N‐acetyl‐L ‐isoleucine‐N‐methylamide, 53 relaxed structures were determined at the DFT (B3LYP/6‐31G(d)) level of theory. An exhaustive electronic study employing the atoms‐in‐molecules (AIM) method was carried out. In addition, the effects of three solvents (water, acetonitrile, and chloroform) were included in the calculations using the isodensity polarizable continuum model (IPCM) method. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2006  相似文献   

14.
Three hundred and thirty two bacterial colonies were isolated from soil contaminated by an oil spill. All the bacteria were cultured in a liquid medium individually, and the surface tensions of the media were compared. The bacterium whose culture medium had the lowest surface tension was identified as Pseudomonas sp. G11. A biosurfactant was produced by cultivation of the Pseudomonas sp. G11 in the LB media. For extraction of the biosurfactant, two solvent systems were used (n-hexane and a 2:1 (v/v) mixture of chloroform/MeOH), and the results were compared. Various experimental conditions (solvent composition, flow rate, etc.) were tested to optimize the analysis of the biosurfactant by asymmetrical flow field-flow fractionation (AsFlFFF). The biosurfactant was successfully separated from the culture medium by AsFlFFF when pure water was used as the carrier. From the retention data, the hydrodynamic diameter (d H) and molecular weight (M) of the biosurfactant were determined by AsFlFFF. The molecular weight was determined by using pullulans as the calibration standards. The d H and M were 49 nm and 2.3 × 105 Da when extracted with n-hexane, and 39 nm and 1.13 × 105 Da when extracted with the 2:1 mixture of chloroform/MeOH, respectively. Figure Separation of biosurfactant from its culture medium by flow FFF  相似文献   

15.
Exfoliated nylon‐11/layered silicate nanocomposites were prepared via in situ polymerization by dispersing organoclay in 11‐aminoundecanoic acid monomer. The original clay was modified by a novel method with 11‐aminoundecanoic acid. In situ Fourier transform infrared spectroscopy results show that stronger hydrogen bonds exist between nylon‐11 and organoclay than that of between nylon‐11 and original clay. The linear dynamic viscoelasticity of organoclay nanocomposites was investigated. Before taking rheological measurements, the exfoliated and intercalating structures and the thermal properties were characterized using X‐ray diffraction, transmission electron microscopy, differential scanning calorimetry, and thermogravimetric analysis. The results show that the clay was uniformly distributed in nylon‐11 matrix during in situ polymerization of clay with 4 wt % or less. The presence of clay in nylon‐11 matrix increased the crystallization temperature and the thermal stability of nanocomposites prepared. Rheological properties such as storage modulus, loss modulus, and relative viscosity have close relationship with the dispersion favorably compatible with the organically modified clay. Comparing with neat nylon‐11, the nanocomposites show much higher dynamic modulus and stronger shear thinning behavior. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 2161–2172, 2006  相似文献   

16.
Three different characterization methods—13C NMR spectroscopy, a terminal terpolymerization model, and a probability analysis based on the Poisson distribution—were used to determine the microstructure of random terpolymers. The methods were used to determine the amino acid sequence distribution of random terpolymers prepared from the polymerization of N‐carboxyanhydrides that contained L ‐leucine, β‐benzyl‐L ‐aspartate, and L ‐valine. Poly(L ‐leucine‐L ‐aspartic acid‐L ‐valine) [poly(LDV)] was designed as a target specific substrate for the α4β1 integrin that recognizes the tripeptide sequence leucine‐aspartic acid‐valine (LDV). The presence of the tripeptide sequence LDV within the polymer was determined to be eight LDV triad sequences on average in terpolymers of approximately 100 kDa. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 4328–4337, 2006  相似文献   

17.
Atom transfer radical polymerizations (ATRPs) of 1‐(4‐methacryloyloxy‐benzyl)thymine (MAT) and 9‐(2‐methacryloyloxyethyl)adenine (MAA) were conducted for the synthesis of DNA‐base functionalized polymers. The association equilibrium constant Kasso between MAT and MAA and the complexation equilibrium constant Kcomp between the corresponding polymers PMAT and PMAA were determined. A zipper‐like diblock copolymer, PMAT‐b‐PMAA, was prepared by anchoring the PMAT and PMAA blocks on the ortho‐positions of a pyridine ring via a successive two‐step ATRP. Dynamic light scattering and atom force microscopy confirmed that the block copolymer had a V‐shaped configuration in dimethylsulfoxide/N,N‐dimethylformamide. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5995–6006, 2006  相似文献   

18.
Low‐charge density ampholytic terpolymers composed of acrylamide (AM), (3‐acrylamidopropyl)trimethyl ammonium chloride (APTAC), and N‐acryloyl‐valine were prepared via free‐radical polymerization in 0.5 M NaCl to yield terpolymers with random charge distributions. Sodium formate (NaOOCH) was employed as a chain transfer agent during the polymerization to suppress gel effects and broadening of the molecular weight distribution (MWD). Terpolymer compositions were determined by 13C NMR spectroscopy. Terpolymer molecular weights (MWs) and polydispersity indices (PDIs) were obtained via size exclusion chromatography/multi‐angle laser light scattering (SEC‐MALLS). Intrinsic viscosity values determined from SEC‐MALLS data using the Flory–Fox relationship were compared with those determined by low‐shear dilute solution viscometry and found to be in good agreement. SEC‐MALLS experiments allowed examination of radius of gyration‐MW (RgM) relationships and the Mark‐Houwink‐Sakurada intrinsic viscosity‐MW ([η]‐M) relationships for terpolymers. The RgM and [η]‐M relationships indicated little or no excluded volume effects under SEC conditions indicating that the terpolymers were in near theta conditions in an aqueous buffer solution. Potentiometric titration experiments were performed in deionized (DI) water. These studies revealed that the apparent pKa of the AMVALTAC terpolymers increases with increasing VAL content. The solution properties of low‐charge density ampholytic terpolymers have been studied as functions of solution pH, ionic strength, and polymer concentration. The charge‐balanced terpolymers exhibit polyampholyte behavior at pH values ≥ 6.5. As solution pH is decreased, these charge‐balanced terpolymers become increasingly cationic due to the protonation of the VAL repeat units. Charge‐imbalanced terpolymers generally exhibit polyelectrolyte behavior, although the effects of intramolecular electrostatic interactions (e.g., polyampholyte effects) on the hydrodynamic volume are evident at certain values of solution pH and salt concentration. The solution behavior of the terpolymers in the dilute regime correlates well with that predicted by various polyampholyte solution theories. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3125–3139, 2006  相似文献   

19.
A novel star‐shaped poly(p‐dioxanone) was synthesized by the ring‐opening polymerization of p‐dioxanone initiated by pentaerythritol with stannous octoate as a catalyst in bulk. The effect of the molar ratio of the monomer to the initiator on the polymerization was studied. The polymers were characterized with 1H NMR and 13C NMR spectroscopy. The thermal properties of the polymers were investigated with differential scanning calorimetry and thermogravimetric analysis. The novel star‐shaped poly(p‐dioxanone) has a potential use in biomedical materials. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 1245–1251, 2006  相似文献   

20.
The original article to which this erratum refers was published in the International Journal of Quantum Chemistry Int J Quantum Chem&;par;2006) .  相似文献   

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