bluuebunny/crossref_metadata_2025 huggingface dataset:
Popular Support for Village Self-Government in China: Intensity and Sources
Authors: Chen Jie
Published: January 2006

Based on survey data collected in Jiangsu Province, this research finds that rural residents' evaluations of self-government institutions were more positive than those of the elected leaders. Villagers' subjective orientations—such as assessment of the village leaders' policy performance, beliefs in democratic institutions, and external efficacy—shaped their attitudes toward both self-government institutions and elected leaders.
Does the Employment Guarantee Scheme Benefit the Rural Poor in India? Some Recent Evidence
Authors: Gaiha Raghav
Published: January 2006

Although participation in the Employment Guarantee Scheme (EGS) in the Indian state of Maharashtra has declined in recent years, the program continues to bring significant transfer and stabilization benefits to some of the least-developed villages during long seasonal slack periods. Because alternative employment options are few and far between, this dependence on the EGS is unavoidably high. This article makes a case for enhanced outlays under the EGS, with a substantially higher reallocation in favor of the least-developed regions and appropriate changes in the scheme's design and implementation.
Dancing on the Rim, Tiptoeing through Minefields
Authors: JAMESON ELIZABETH
Published: January 2006

This article uses border crossings by the author's family to illustrate the problems of historical narratives that do not consider who and what exists beyond national borders,as well as across conceptual boundaries of race, class, ethnicity, religion, gender,and sexuality. The national U.S. narrative rarely crosses the borders of what became three North American nations, or those between a pre-colonial North American past and a post-colonial national history, or profound social divisions. Histories that cross national and social boundaries clarify what Sarah Carter terms their "categories and terrains of exclusion." Fears triggered by the attacks of September 11, 2001, revealed changing constructions of the U.S.-Canadian border. Without stories that cross national and social divides, it is hard to recognize humanity across those borders or to imagine a connected future. Such histories must recognize analytic categories and narratives divided and erased by social and national borders, and the unequal power inscribed in androcentric, ethnocentric, and nationalist narratives.
The Two Mrs. Cheneys
Authors: ALLMENDINGER BLAKE
Published: January 2006

This commentary reviews Sisters, Lynne Cheney's Western historical novel. The novel seems to be at odds with Cheney's conservative political views. It considers feminism,lesbianism, and Native Americans in a positive light and is critical of U.S. empire and capitalism as practiced on the early Wyoming frontier. The author considers why Cheney may have felt freer to explore such topics in literature, even though she has not embraced these liberal positions in her political speeches and writings over the years. There seem to be two Mrs. Cheneys, the creative writer and free-thinker, and the conservative wife of the Republican Vice President.
Oyster Growers and Oyster Pirates in San Francisco Bay
Authors: BOOKER MATTHEW MORSE
Published: January 2006

In the late nineteenth century San Francisco Bay hosted one of the American West's most valuable fisheries: Not the bay's native oysters, but Atlantic oysters, shipped across the country by rail and seeded on privately owned tidelands, created private profits and sparked public resistance. Both oyster growers and oyster pirates depended upon a rapidly changing bay ecosystem. Their struggle to possess the bay's productivity revealed the inqualities of ownership in the American West. An unstable nature and shifting perceptions of San Francisco Bay combined to remake the bay into a place to dump waste rather than to find food. Both growers and pirates disappeared following the collapse of the oyster fishery in the early twentieth century.
Use of Electromyogram Telemetry to Assess Swimming Activity of Adult Spring Chinook Salmon Migrating Past a Columbia River Dam
Authors: Brown Richard S. , Geist David R. , Mesa Matthew G.
Published: January 2006

Electromyogram (EMG) radiotelemetry was used to estimate the swim speeds of spring Chinook salmon Oncorhynchus tshawytscha migrating upstream past a Columbia River dam. Electrodes from EMG transmitters were surgically implanted in the red muscle of fish captured at Bonneville Dam, and output from the tags was calibrated to defined swim speeds for each fish in a tunnel respirometer. The fish were then released below Bonneville Dam and radio‐tracked as they migrated through the tailraces, fishways, and forebays of the dam. On average, swim speed was significantly higher when tagged salmon were moving through tailraces than when they were moving through other parts of the dam. Specifically, swim speeds for fish in tailraces (106.4 cm/s) were 23% higher than those of fish in fishways (84.9 cm/s) and 32% higher than those of fish in forebays (80.2 cm/s). Swim speeds were higher in fishways during the day than during the night, but there were no diel differences in swim speeds in tailraces and forebays. During dam passage, Chinook salmon spent the most time in tailraces, followed by fishways and forebays.
Seroprevalence of feline leukemia virus and feline immunodeficiency virus infection among cats in North America and risk factors for seropositivity
Authors: Levy Julie K. , Scott H. Morgan , Lachtara Jessica L. , Crawford P. Cynda
Published: January 2006

Objective—To determine seroprevalence of FeLV and FIV infection among cats in North America and risk factors for seropositivity.

Design—Prospective cross-sectional survey.

Animals—18,038 cats tested at 345 veterinary clinics (n = 9,970) and 145 animal shelters (8,068) between August and November 2004.

Procedure—Cats were tested with a point-of-care ELISA for FeLV antigen and FIV antibody. A multivariable random effects logistic regression model was used to identify risk factors significantly associated with seropositivity while accounting for clinic-to-clinic (or shelter) variability.

Results—409 (2.3%) cats were seropositive for FeLV antigen, and 446 (2.5%) cats were seropositive for FIV antibody; 58 (0.3%) cats were seropositive for infection with both viruses. Multivariable analysis indicated that age, sex, health status, and cat lifestyle and source were significantly associated with risk of seropositivity, with adults more likely to be seropositive than juveniles (adjusted odds ratios [ORs], 2.5 and 2.05 for FeLV and FIV seropositivity, respectively), sexually intact adult males more likely to be seropositive than sexually intact adult females (adjusted ORs, 2.4 and 4.66), and outdoor cats that were sick at the time of testing more likely to be seropositive than healthy indoor cats (adjusted ORs, 8.89 and 11.3).

Conclusions and Clinical Relevance—Results suggest that certain characteristics, such as age, sex, health status, and lifestyle, are associated with risk of FeLV and FIV seropositivity among cats in North America. However, cats in all categories were found to be at risk for infection, and current guidelines to test all cats at the time of acquisition and again during illness should be followed.
Use of ultrasonography to diagnose large colon volvulus in horses
Authors: Abutarbush Sameeh M.
Published: January 2006

Objective—To describe the use of ultrasonography to diagnose large colon volvulus (LCV) in horses.

Design—Descriptive report.

Animals—4 horses with clinical signs of abdominal pain.

Procedure—Each horse was administered analgesic agents for pain control and placed in stocks. Ultrasonographic evaluations were performed with a 3.5-MHz sector scanning transducer that was placed parallel to the long axis of the horse (longitudinal imaging) over an area of the left ventral aspect of the abdomen. The boundaries of the evaluated region included the ventral midline, 2 vertical lines at the level of the left 10th and 17th intercostal spaces, and a horizontal line between the 2 vertical lines at the level of the costal arch of the left 10th intercostal area.

Results—In all horses, nonsacculated large colon was identified ultrasonographically in the left ventral portion of the abdomen; this finding was considered indicative of LCV. In 3 horses, the LCV involved intestinal rotation of 180°, whereas in 1 horse, the LCV involved intestinal rotation of 540°. As confirmed by surgical or postmortem findings, the degree and location of the volvulus were correctly estimated from ultrasonographic images.

Conclusions and Clinical Relevance—In horses, this method of diagnosis of LCV appears to be of value regardless of the location at which the rotation of the large colon occurs. Ultrasonographic findings may aid in the earlier diagnosis of LCV in horses, especially at an early stage of the disease when other clinical signs are equivocal.
Hydraulic permeabilities of PET and nylon 6 electrospun fiber webs
Authors: Hwa Hong Kyung , Jin Kang Tae
Published: January 2006

The morphological and hydraulic properties of electrospun fiber webs were investigated and compared with those of spunbond nonwoven fabrics. In this study, poly(ethylene terephthalate) (PET), hydrophobic polymer, and nylon 6, with some hydrophilic groups (amide groups), were used as the polymer materials to prepare spunbonds and electrospun fiber webs. The water permeabilities of PET and nylon 6 spunbonds followed the Darcy's law, but those of PET and nylon 6 electrospun fiber webs showed properties that deviated from the Darcy's law. On the other hand, the wicking phenomenon was observed in both nylon 6 spunbond and electrospun fiber webs, but no such phenomenon was observed in PET spunbond and electrospun fiber webs. The water vapor transport rates of PET and nylon 6 electrospun fiber webs were higher than those of PET and nylon 6 spunbonds. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 167–177, 2006
Nonionic water‐soluble polymer: Preparation, characterization, and application of poly(1‐vinyl‐2‐pyrrolidone‐co‐hydroxyethylmethacrylate) as a polychelatogen
Authors: Pizarro Guadalupe Del C. , Marambio Oscar G. , Jeria O Manuel , Huerta Margarita , Rivas Bernabé L.
Published: January 2006

The free‐radical copolymerization of water‐soluble poly(1‐vinyl‐2‐pyrrolidone‐co‐hydroxyethylmethacrylate) was carried out with a feed monomer ratio of 75:25 mol %, and the total monomer concentration was 2.67M. The synthesis of the copolymer was carried out in dioxane at 70°C with benzoyl peroxide as the initiator. The copolymer composition was obtained with elemental analysis and 1H‐NMR spectroscopy. The water‐soluble polymer was characterized with elemental analysis, Fourier transform infrared, 1H‐ and 13C‐NMR spectroscopy, and thermal analysis. Additionally, viscosimetric measurements of the copolymer were performed. The thermal behavior of the copolymer and its complexes were investigated with differential scanning calorimetry (DSC) and thermogravimetry techniques under a nitrogen atmosphere. The copolymer showed high thermal stability and a glass transition in the DSC curves. The separation of various metal ions by the water‐soluble poly(1‐vinyl‐2‐pyrrolidone‐co‐hydroxyethylmethacrylate) reagent in the aqueous phase with liquid‐phase polymer‐based retention was investigated. The method was based on the retention of inorganic ions by this polymer in a membrane filtration cell and subsequent separation of low‐molar‐mass species from the polymer/metal‐ion complex formed. Poly(1‐vinyl‐2‐pyrrolidone‐co‐hydroxyethylmethacrylate) could bind metal ions such as Cr(III), Co(II), Zn(II), Ni(II), Cu(II), Cd(II), and Fe(III) in aqueous solutions at pHs 3, 5, and 7. The retention percentage for all the metal ions in the polymer was increased at pH 7, at which the maximum retention capacity could be observed. The interaction of inorganic ions with the hydrophilic polymer was determined as a function of the pH and filtration factor. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 178–185, 2006
Depolymerization of nylon 6 waste fibers
Authors: Shukla S. R. , Harad Ajay M. , Mahato D.
Published: January 2006

The depolymerization of nylon 6 was carried out with various solvents, such as formic acid, hydrochloric acid, and sulfuric acid, followed by heating under reflux for different times. From the polymer dissolved and refluxed in formic acid, degradation products with different ranges of molecular weights were collected by fractional precipitation, with small lots of distilled water added as a nonsolvent. The characterization of different fractions was carried out by the measurement of the viscosity‐average molecular weight, the number‐average molecular weight, and the number of amino end groups. The presence of the monomer, aminocaproic acid, was confirmed by thin‐layer chromatography in the case of hydrochloric acid treated nylon 6. With a strongly acidic ion‐exchange resin, the monomer was separated in its purest form, and the melting point was noted. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 186–190, 2006
Application of cyclodextrin to the textile dyeing and washing processes
Authors: Cireli Aysun , Yurdakul Birkan
Published: January 2006

Cyclodextrins can form inclusion complexes with different molecules with the aid of their special chemical (molecular) structures. Physical and chemical properties of molecules can change after the formation of complex. This special feature enables the usage of dextrins in different industry areas. In this study, applicability of cylcodextrins in textile dyeing and washing processes was investigated. With this aim, β‐cyclodextrin was used in direct dyeing of cellulosic fabrics and in rinsing processes of direct dyed fabrics. Retarder/leveling effect of β‐cyclodextrin in dyeing process has been studied and the results were compared with that of a commercial product. In general, cyclodextrins were used in washing processes to remove the absorbed surfactants. It has been investigated whether this effect was the same for washing of dyed fabrics. Eight different direct dyes, for which the chemical structures are known, were used in dyeing and washing processes, and effect of β‐cyclodextrin on different chemical structures was investigated. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 208–218, 2006
Effects of mercerization of bamboo strips on mechanical properties of unidirectional bamboo–novolac composites
Authors: Das Mahuya , Pal Anindya , Chakraborty Debabrata
Published: January 2006

Bamboo strip reinforced novolac resin composites were fabricated using bamboo strips that were treated with varying concentrations of sodium hydroxide solution at a constant filler loading (25%). The mechanical properties of various composites (flexural modulus, toughness, tensile strength, and elastic modulus) were determined. The physical characteristics, such as the wetting ability of the alkali treated reinforcements, were increased because of alkali treatment. With increasing concentrations of alkali, a higher percent loss in weight occurred. The mechanical properties were increased with increasing mercerizing strength. Maximum improvement in properties was achieved with 16–20% of caustic treated reinforcements. An FTIR study indicated aryl alkyl ether formation with OH groups of cellulose and methylol groups of novolac resin. Beyond 20% there was degradation in all strength properties because of the failure in the mechanical properties of the reinforcements. A correlation was found to exist between the mechanical properties and the developed morphology. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100:238–244, 2006
Selective separation of In(III), Ga(III), and Zn(II) from dilute solution using solvent‐impregnated resin containing Di(2‐ethylhexyl) phosphoric acid
Authors: Liu J. S. , Chen H. , Guo Z. L. , Hu Y. C.
Published: January 2006

The aim of this work was to study the separation of In(III), Ga(III), and Zn(II) from sulfate solution using solvent‐impregnated resin containing di(2‐ethylhexyl) phosphoric acid. The influence of pH on the extraction of each metal was determined. Extraction isotherms were then studied at selected pH. Results showed that In(III) can be first extracted from aqueous solutions at pH 2 using the resin, then Ga(III) and Zn(II) coextracted at pH 3, and the separation can be carried out by using different concentrations of eluents. Loaded resins can be regenerated, and the metals can be recovered selectively. Two fixed‐bed columns arranged in series were successfully used for the separation and recovery of these three metal ions from multi‐component solution. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 253–259, 2006
CO2‐facilitated transport through poly(N‐vinyl‐γ‐sodium aminobutyrate‐co‐sodium acrylate)/polysulfone composite membranes
Authors: Wang Zhi , Yi Chunhai , Zhang Ying , Wang Jixiao , Wang Shichang
Published: January 2006

Poly(N‐vinyl‐γ‐sodium aminobutyrate‐co‐sodium acrylate) (VSA–SA)/polysulfone (PS) composite membranes were prepared for the separation of CO2. VSA–SA contained secondary amines and carboxylate ions that could act as carriers for CO2. At 20°C and 1.06 atm of feed pressure, a VSA–SA/PS composite membrane displayed a pure CO2 permeation rate of 6.12 × 10−6 cm3(STP)/cm2 s cmHg and a CO2/CH4 ideal selectivity of 524.5. In experiments with a mixed gas of 50 vol % CO2 and 50 vol % CH4, at 20°C and 1.04 atm of feed pressure, the CO2 permeation rate was 9.2 × 10−6 cm3 (STP)/cm2 s cmHg, and the selectivity of CO2/CH4 was 46.8. Crosslinkages with metal ions were effective for increasing the selectivity. Both the selectivity of CO2 over CH4 and the CO2 permeation rate had a maximum against the carrier concentration. The high CO2 permeation rate originated from the facilitated transport mechanism, which was confirmed by Fourier transform infrared with attenuated total reflectance techniques. The performance of the membranes prepared in this work had good stability. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 275–282, 2006
Morphology and mechanical properties of polypropylene/polyamide 6 nanocomposites prepared by a two‐step melt‐compounding process
Authors: Gahleitner Markus , Kretzschmar Bernd , Pospiech Doris , Ingolic Elisabeth , Reichelt Norbert , Bernreitner Klaus
Published: January 2006

Polypropylene/polyamide 6 blends and their nanocomposites with layered silicates or talc were prepared in a melt‐compounding process to explore their mechanical performance. The thermomechanical behavior, crystallization effects, rheology, and morphology of these materials were studied with a wide range of experimental techniques. In all cases, the inorganic filler was enriched in the polyamide phase and resulted in a phase coarsening of the polypropylene/polyamide nanocomposite in comparison with the nonfilled polypropylene/polyamide blend. The mechanical properties of these nanoblends were consequently only slightly better than those of the pure polymers with respect to the modulus, whereas the impact level was below that of the pure polymers, reflecting the heterogeneity of the nanoblend. Polymer‐specific organic modification of the nanoclays did not result in a better phase distribution, which would be required for better overall performance. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 283–291, 2006
Thermal characterization of carbon‐nanofiber‐reinforced tetraglycidyl‐4,4′‐diaminodiphenylmethane/4,4′‐diaminodiphenylsulfone epoxy composites
Authors: Xie Hongfeng , Liu Binghua , Yang Hu , Wang Zhiliu , Shen Jianyi , Cheng Rongshi
Published: January 2006

The thermal properties of carbon nanofibers (CNF)/epoxy composites, composed of tetraglycidyl‐4,4′‐diaminodiphenylmethane (TGDDM) resin and 4,4′‐diaminodiphenylsulfone (DDS) as a curing agent, were investigated with differential scanning calorimetry (DSC), thermogravimetric analysis, and dynamic mechanical thermal analysis. DSC results showed that the presence of CNF had no pronounced influence on the heat of the cure reaction. However, the incorporation of CNF slightly improved the thermal stability of the epoxy. Furthermore, the storage modulus of the TGDDM/DDS epoxy was significantly enhanced, whereas the glass‐transition temperature was not significantly affected, upon the incorporation of CNFs. The storage modulus of 5 wt % CNF/epoxy composites at 25°C was increased by 35% in comparison with that of the pure epoxy. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 295–298, 2006
Synthesis and luminescence properties of new blue‐light‐emitting polyconjugated poly{1,1′‐biphenyl‐4,4′‐diyl‐[1‐(4‐t‐butylphenyl)]vinylene} polymers and copolymers
Authors: Kim Chang‐Gyu , Joo Sung‐Hoon , Hong Cheon Cheol , Jeong Mi‐Yun , Cha Soon‐Wook , Sohn Byung‐Hee , Jin Jung‐Il
Published: January 2006

Three new soluble polyconjugated polymers, all of which emitted blue light in photoluminescence and electroluminescence, were synthesized, and their luminescence properties were studied. The polymers were poly{1,1′‐biphenyl‐4,4′‐diyl‐[1‐(4‐t‐butylphenyl)]vinylene}, poly((9,9‐dioctylfluorene‐2,7‐diyl)‐alt‐{1,4‐phenylene‐[1‐(4‐t‐butylphenyl)vinylene‐1,4‐phenylene]}) [P(DOF‐PVP)], and poly([N‐(2‐ethyl) hexylcarbazole‐3,6‐diyl]‐alt‐{1,4‐phenylene‐[1‐(4‐t‐butylphenyl)]vinylene‐1,4‐phenylene}). The last two polymers had alternating sequences of the two structural units. Among the three polymers, P(DOF‐PVP) performed best in the light‐emitting diode devices of indium–tin oxide/poly(ethylenedioxythiophene) doped with poly(styrene sulfonate) (30 nm)/polymer (150 nm)/Li:Al (100 nm). This might have been correlated with the balance in and magnitude of the mobility of the charge carriers, that is, positive holes and electrons, and also the electronic structure, that is, highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) levels, of the polymers. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 307–317, 2006
Synthesis of acrylate polymers by a novel emulsion polymerization for adhesive applications
Authors: Sakdapipanich Jitladda , Thananusont Narumol , Pukkate Nanthaporn
Published: January 2006

Pressure‐sensitive adhesives (PSAs) are viscoelastic–elastomeric materials that can adhere strongly to solid surfaces with light contact pressure and a short contact time. Polyacrylates produced by solution polymerization are used widely because of their good adhesive properties. A novel emulsion polymerization was established to improve the low physical properties of PSA on the basis of conventional poly(n‐butyl acrylate) (PBA) by emulsion polymerization. PBA latex was synthesized by the emulsion polymerization of 50 wt % n‐butyl acrylate mixed with 15 wt % ethyl acetate (EA) with Emal‐10P and Emulgen‐920 as anionic and nonionic surfactants, respectively, at 70°C. Potassium persulfate (KPS) or a combination of KPS and dicumyl peroxide (DCP) was used as the initiator. The KPS/DCP system gave a very high‐molecular‐weight PBA of a narrow molecular weight distribution with a weight‐average molecular weight/number‐average molecular weight value of 1.01–1.03 in 15 min. The PSA tape was prepared by the casting of the PSA latex onto a corona poly(ethylene terephthalate) film as an adherent to obtain a 50‐μm‐dry‐thickness film. The PSA tape produced from PBA by the novel emulsion polymerization showed better adhesive properties, such as 180° peel adhesion, shear holding power, and rolling ball tack tests according to JIS and ASTM standards, than PSA tape produced from solution polymerization. The occlusion of a small amount of EA in emulsion particles before polymerization was found to give higher properties than those of PBA prepared by the addition of EA to the PBA latex after polymerization. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100:413–421, 2006
Preparation of compatible blends of poly(methyl methacrylate) used in dentistry with a reactive terpolymer containing maleic anhydride and their thermomechanical characterization
Authors: Boztuğ Ali , Coşkun Akın , Bolayır Giray , Zengin H. Bayram , Özdemir Ali Kemal
Published: January 2006

This study focuses on the preparation of compatible blends with the poly(methyl methacrylate) (PMMA) using a reactive terpolymer maleic anhydride–styrene–vinyl acetate (MA–St–VA). In the first series of experiments, binary blends of the PMMA and the MA–St–VA terpolymer have been prepared in tetrahydrofurane. The PMMA and the MA–St–VA terpolymer formed the compatible blends. The effects on thermomechanical properties of MA–St–VA terpolymer ratio in the blends were studied. The glass transition temperatures (Tg), thermal expansion coefficient (α), and other thermomechanical parameters for the blends have been established by TMA method and the compatibility of two polymers has been evaluated by these TMA parameters. The addition of MA–St–VA terpolymer to PMMA made a plasticizing effect on PMMA. This effect regularly changed with the increasing of the terpolymer in the blends. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 363–367, 2006
Photophysical studies of copolymers of N‐vinylcarbazole
Authors: Brar A. S. , Kaur Manpreet , Balamurli M. M. , Dogra S. K.
Published: January 2006

The absorption, fluorescence excitation and emission spectroscopy, and time‐dependent spectrofluorimetry have been used to study the photophysics of copolymers of N‐vinylcarbazole with different monomers like vinyl acetate, methyl acrylate, methyl methacrylate, butyl acrylate, and butyl methacrylate in dichloromethane. In all the copolymers and at different N‐vinylcarbazole content, the absorption spectra reflect only the monomer carbazole units. The two kinds of excited monomer species of N‐vinylcarbazole are present in S1 state. Short‐lived (∼3 ns) excited monomer decays forming low energy excimer obtained by the complete overlap of the excited carbazole monomer. The long‐lived excited monomer (∼8 ns) decays to ground state without formation of any excimer. The high energy excimer is relatively short‐lived and is formed by the partial overlap of the carbazole units. The presence of bulky group in the copolymer chain hinders the formation of excimers. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 372–380, 2006
Synthesis, thermal properties, and morphology of blocked polyurethane/epoxy full‐interpenetrating polymer network
Authors: Chen Chin‐Hsing , Chen Meng‐Huei
Published: January 2006

Blocked polyurethane (PU)/epoxy full‐interpenetrating polymer network (full‐IPN) were synthesized from blocked NCO‐terminated PU prepolymer, with 4,4‐methylene diamine as a chain extender and epoxy prepolymer, with 4,4‐methylene diamine as a curing agent, using simultaneous polymerization (SIN) method. From FTIR spectra analysis it was found that the major reactions in the blocked PU/epoxy IPN system are the self‐polymerization of block PU/chain extender and the self‐polymerization of epoxy/curing agent. Meanwhile, from reaction mechanisms the copolymerization of IPN may have occurred at the same time. The weight loss by thermogravimetric analysis decreased with increasing epoxy and filler content. It was confirmed from scanning electron micrography (SEM) that when the blocked PU content increased, the microstructure of IPN became rougher. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 323–328, 2006
Development of a photoresponsive cell culture surface: Regional enhancement of living‐cell adhesion induced by local light irradiation
Authors: Tada Yuichi , Sumaru Kimio , Kameda Mitsuyoshi , Ohi Katsuhide , Takagi Toshiyuki , Kanamori Toshiyuki , Yoshimi Yasuo
Published: January 2006

Using a functional polymer containing nitrospirobenzopyran residues and poly(ethylene glycol), we developed a photoresponsive cell culture surface (PRCS), at which the cell adhesion can be enhanced locally by UV light irradiation (350–400 nm, 35 mW/cm2, 5 min) even on the region where living cells exist. Cell adhesion was evaluated by observing BALB/3T3 fibroblasts, which had been seeded on PRCS and then irradiated with UV light regionally, after 12 h incubation and subsequent washing to remove scarcely adhering cells. As a result, it was confirmed that the number of remaining cells in irradiated region was at most 2.5 times greater than that in nonirradiated regions, suggesting the implementation of a novel scheme to manipulate living cells individually by light irradiation in a parallel and simultaneous manner. Influence of the composition of the polymer material consisting the substrate surface was also investigated systematically. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 495–499, 2006
Rheology of poly(N‐vinyl pyrrolidone)–poly(ethylene glycol) adhesive blends under shear flow
Authors: Feldstein Mikhail M. , Kulichikhin Valery G. , Kotomin Sergey V. , Borodulina Tatiana A. , Novikov Mikhail B. , Roos Alexandra , Creton Costantino
Published: January 2006

The rheological properties of adhesive miscible blends of high‐molecular‐weight poly(N‐vinyl pyrrolidone) (PVP) with short‐chain poly(ethylene glycol) (PEG) under oscillatory and steady‐state shear flow have been examined with dynamic mechanical and squeezing‐flow analysis. The latter allows the rheological characterization of adhesive blends under conditions modeling adhesive‐bond formation as a fixed compressive force is applied to an adhesive film. The most adhesive PVP blend with 36 wt % PEG has been established to flow like a viscoplastic (yield stress) liquid with a power‐law index of about 0.12. The study of the apparent yield stress as a function of the PVP–PEG composition, content of sorbed water, molecular weight of PVP, and temperature shows that the occurrence of a yield stress in the blends results most likely from a noncovalent crosslinking of PVP macromolecules through short PEG chains by means of hydrogen bonding of both terminal OH groups of PEG to the complementary functional groups in PVP monomer units. A molecular mechanism of PVP–PEG interaction was established earlier by direct and independent methods. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 522–537, 2006
Novel self‐disinfecting surface
Authors: McCubbin P. J. , Forbes E. , Gow M. M. , Gorham S. D.
Published: January 2006

The colonization of medical devices by micro‐organisms is an ongoing problem, particularly as many strains of bacteria are becoming resistant to antibiotics. One method by which this could be addressed is the production of a surface that will kill bacteria on contact without releasing the disinfecting agent into solution. Self‐disinfecting surfaces were prepared in which a quaternary ammonium salt was covalently bound onto a polyethylene film by a stable linkage. To achieve this, a low‐density polyethylene film was treated with glow discharge followed by the graft polymerization of acrylic acid. The acid chloride derivative was then prepared. α,ω‐Dibromoalkanes of various chain lengths were reacted with potassium phthalimide to form anN‐alkylphthalimido group, and this was followed by an excess of piperidine to produce a tertiary amino group at the opposite end of the alkyl chain. The hydrolysis of the phthalimido group produced a primary amino function that was coupled to the grafted poly(acryl chloride). A reaction with octadecyl bromide resulted in the production of a quaternary ammonium salt. The amide linkage by which the quaternary ammonium salt was attached to the polymer was stable, and no release of the disinfecting moiety took place in solution. Soluble compounds containing a similar quaternary ammonium function were prepared through the reaction of the primary amine group with acetyl chloride rather than the polymeric acid chloride to form substitutedN‐acetamides. In a microbiological pilot study, both the polymer‐bound and soluble quaternary ammonium salts were effective against suspensions ofStaphylococcus aureus,Escherichia coli, andSaccharomyces cerevisiae. The results show that a self‐disinfecting surface can be produced in which the quaternary ammonium function is an effective bacteriocide that remains bound to the polymer surface. In addition, the materials were toxic to a mammalian cell line (Chinese hamster ovary cells). © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 381–389, 2006
Covalent attachment of quaternary ammonium compounds to a polyethylene surface via a hydrolyzable ester linkage: Basis for a controlled‐release system of antiseptics from an inert surface
Authors: McCubbin P. J. , Forbes E. , Gow M. M. , Gorham S. D.
Published: January 2006

The colonization of medical devices such as catheters, topical wound dressings, and surgical implants by micro‐organisms is an ongoing problem, particularly as many strains of bacteria are becoming resistant to antibiotics. Such a problem may be addressed by a material surface that is able to provide a slow release of a disinfectant during its period of usage. To achieve this objective, a novel material was prepared in which a quaternary ammonium salt was covalently bound onto a polyethylene backbone via a hydrolyzable ester linkage, which provided a slow release of the disinfecting agent. A low‐density polyethylene film was treated with glow discharge followed by the graft polymerization of acrylic acid. A tertiary amine function was introduced onto the film by the esterification of the carboxylic acid groups, via an acid chloride intermediate, with 4‐hydroxy‐N‐methyl piperidine. The tertiary amine on the piperidine was then quaternized with a series of alkyl bromides of various chain lengths. The quaternary ammonium salt was released slowly by the hydrolysis of the ester bond over a 4‐h period. To test the efficacy of the quaternary ammonium function itself, soluble compounds were prepared as follows. 4‐Hydroxy‐N‐methyl piperidine was esterified with acetic anhydride and a corresponding series of quaternary ammonium salts prepared again by a reaction with alkyl bromides of various chain lengths. A preliminary microbiological survey of the materials included an investigation of the effect of the chain length as well as the efficacy of the soluble quaternary salts themselves. As expected, only the longer alkyl chains provided quaternary ammonium salts with bactericidal properties, chain lengths of less than 10 carbon atoms proving ineffective. Both the polymer‐bound and soluble long‐chain quaternary ammonium salts were effective against suspensions of Staphylococcus aureus and Escherichia coli. The results therefore indicate that such a system may well be useful in the development of biomedical materials such as surgical implants or dressings in which a slow release of a disinfectant or other physiologically active agent such as an anti‐inflammatory drug may be required. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 538–545, 2006
Preparation and application of acrylonitrile‐grafted cyanoethyl cellulose for the removal of copper (II) ions
Authors: Kamel S. , Hassan E. M. , El‐Sakhawy M.
Published: January 2006

Cyanoethyl cellulose (CE‐Cell) with two different degrees of substitution of 0.37 and 0.60 were prepared from cotton linter. The ionic‐xanthate method was used to graft the acrylonitrile onto CE‐Cell to form acrylonitrile‐grafted cyanoethyl cellulose (GCE‐Cell). The conditions of grafting such as sodium hydroxide concentration, grafting time, monomer concentration, and temperature were optimized. The hydrolyzed CE‐Cell and GCE‐Cell were applied for the adsorption of copper (II) ions from aqueous solution. IR spectroscopy was also used for further evaluation of CE‐Cell and GCE‐Cell. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 329–334, 2006
Reversible addition–fragmentation chain transfer polymerization of styrene with benzoimidazole dithiocarbamate as a reversible addition–fragmentation chain transfer agent
Authors: Yin Haisu , Zhu Xiulin , Zhou Di , Zhu Jian
Published: January 2006

Two novel dithiocarbamates [2‐Y‐benzoimidazole‐1‐carbodithioic acid benzyl esters: Y = methyl (1b) or phenyl (1c)] were synthesized and successfully used in the reversible addition–fragmentation chain transfer (RAFT) polymerization of styrene in bulk with thermal initiation. The effects of the temperatures and concentration ratios of the styrene and RAFT agents on the polymerization were investigated. The results showed that the polymerization of styrene could be well controlled in the presence of 1b or 1c. The linear relationships between ln([M]0/[M]) and the polymerization time (where [M]0 is the initial monomer concentration and [M] is the monomer concentration) indicated that the polymerizations were first‐order reactions with respect to the monomer concentration. The molecular weights increased linearly with the monomer conversion and were close to the theoretical values. The molecular weight distributions [weight‐average molecular weight/number‐average molecular weight (Mw/Mn)] were very narrow from 5.3% conversion up to 94% conversion (Mw/Mn < 1.3). © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 560–564, 2006
Flame retardancy of a polycarbonate–polydimethylsiloxane block copolymer: The effect of the dimethylsiloxane block size
Authors: Nodera Akio , Kanai Toshitaka
Published: January 2006

This report describes the flame retardancy of a polycarbonate (PC)–polydimethylsiloxane (PDMS) block copolymer with a dimethylsiloxane (DMS) block size of 15–350 units, and the effects of the block size and amount of DMS on the flame retardancy are studied. PC–PDMS block copolymers with DMS units of 40–130 had high limiting oxygen index values with 1.0 wt % PDMS. The PDMS block size influenced the PDMS dispersibility in PC, and a moderate PDMS dispersion (ca. 50 nm) caused high flame retardancy for PC. These PC–PDMS block copolymers could form a lot of fine bubbles in the role of good thermal insulators through the reaction of PC and PDMS in combustion. Furthermore, the silica particles from PDMS remained mostly on the surface of the char, so the amount of char with high oxidation resistance increased. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 565–575, 2006
Surface segregation of polyethylene in low‐density polyethylene/ethylene–propylene–diene rubber blends: Aspects of component structure
Authors: Bieliński Dariusz M. , Kaczmarek łukasz
Published: January 2006

Aspects of the molecular weight and its distribution, the branching of low‐density polyethylene (LDPE), and the molecular composition of the ethylene–propylene–diene rubber (EPDM) matrix are presented in this article in terms of their influence on the surface segregation of polyethylene (PE) in elastomer/plastomer blends. All of the PEs studied, despite different weight‐average molecular weights and degrees of branching, segregated to the surface of the LDPE/EPDM blends. Atomic force microscopy pictures demonstrated defective crystalline structures on the surface of the blends, which together with a decrease in the degrees of their bulk crystallinity and a simultaneous increase in their melting temperatures, pointed to a low molecular weight and a defective fraction of PE taking part in the surface segregation. The extent of segregation depended on the molecular structure of the EPDM matrix, which determined the miscibility of the components on a segmental level. The higher the ethylene monomer content in EPDM was, the lower was the PE content in the surface layer of the blends. The composition and structure of the surface layer was responsible for its lower hardness in comparison with the bulk of the blends studied. The surface gradient of the mechanical properties depended on the physicochemical characteristics of the components and the blend composition, which created the possibility of tailoring the LDPE/EPDM blends to dedicated applications. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 625–633, 2006
Synthesis and characterization of soluble hyperbranched polymer via initiator‐fragment incorporation radical polymerization of divinylbenzene with dimethyl 2,2′‐azobisisobutyrate
Authors: Hirano Tomohiro , Higashida Naoki , Wang Hongwei , Sato Makiko Seno Tsuneyuki
Published: January 2006

The homopolymerization of divinylbenzene (DVB) as an excellent crosslinker (0.20 mol/L) with dimethyl 2,2′‐azobisisobutyrate (MAIB) proceeded homogeneously without any gelation at 80°C in benzene when the MAIB concentrations as high as 0.30–0.50 mol/L were used, yielding soluble polymers. In the polymerization at the concentrations of [DVB] = 0.20 mol/L and [MAIB] = 0.50 mol/L, the polymer yield increased with time and leveled off over 90 min. The molecular weight and molecular weight distribution increased with polymer yield. The vinyl groups of DVB were observed to be almost completely consumed in about 80 min, by FT near‐IR spectroscopic analysis. The homogeneous polymerization system involved ESR‐observable polymer radical, the concentration of which increased with time up to 3.4 × 10−5 mol/L. The polymer formed in the polymerization for 2 h consisted of 46 mol % of DVB unit and 54 mol % of the methoxycarbonylpropyl group as MAIB fragment, indicating that an initiator‐fragment incorporation radical polymerization proceeds in the present polymerization. The polymer was soluble in benzene, tetrahydrofuran, ethyl acetate, chloroform, acetone, and N,N‐dimethylformamide, while it was insoluble in n‐hexane, acetonitrile, dimethyl sulfoxide, methanol, and water. The results of the multiangle laser light scattering and viscometric measurements revealed that the individual polymer molecules were formed as hyperbranched polymer nanoparticles. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 664–670, 2006
Study on preparation of protein‐imprinted soft‐wet gel composite microspheres with magnetic susceptibility and their characteristics. I. Preparation and particle morphology
Authors: Lu Shulai , Cheng Guoxiang , Pang Xingshou
Published: January 2006

Protein‐imprinted soft‐gel composite microspheres with magnetic susceptibility (MS‐PIGMs) were prepared by inverse suspension polymerization, using Fe3O4 particles as magnetically susceptible component, acrylamide (AM) and N,N′‐methylenebisacrylamide (BisAM) as polymeric matrix components, toluene as solvent, and bovine serum albumin (BSA) and lysozyme (Lyz) as templates, respectively. The surface morphology of MS‐PIGMs was observed by environmental scanning electron microscope (ESEM) and scanning electron microscope (SEM). The effects of the kinds and amount of dispersants, stirring rate, the amount and adding methods of initiator, the amount of Fe3O4 and monomer concentration on particle morphology of MS‐PIGMs, as well as the effects of crosslinking degree on swelling ratio and particle morphology in wet condition were investigated in detail. ESEM and SEM photographs showed that the resulting MS‐PIGMs were all spheroid form and had large quantity of regularly distributed pores in wet condition, which close in dry condition, and the experimental results indicated that all the affecting factors had obvious effects on particle morphology of MS‐PIGMs. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 684–694, 2006
Elastic properties of natural rubber tubes produced by dip‐coating
Authors: Neves‐Junior W. F. P. , Graeff C. F. de O. , Ferreira M. , Mulato M. , Bernardes M. S. , Coutinho‐Netto J.
Published: January 2006

The mechanical properties of rubber tubes produced by dip‐coating technique and the influence of the fabrication process on their structural properties were evaluated. Cyclic tension versus deformation tests were performed to investigate the elastic properties of the samples and to understand the changes in rubber tubes behavior under repetitive stress. The effect of the wall thickness on the elastic response of the tubes was also studied. The mechanical properties of opened tubes were also investigated for transversal and longitudinal directions to evaluate the influence of the fabrication process on the alignment of the polymer chains. This investigation indicated that the fabricated tubes are resistant and extremely elastic. They can be elongated up to 800% of its initial length before rupture, and thicker tubes are a bit more resistant to elongation than the thinner ones. In addition, the fabricated tubes have an anisotropic structure due to the fabrication process. Finally, natural rubber tubes may have a great potential to be used as vascular prosthesis, or in other applications that require a large range of resistance and elasticity. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 702–707, 2006
Combination of atomic force microscopy and chemical hydrolysis to characterize degradable regions in polymer blends
Authors: Gu X. , Raghavan D. , Emekalam A.
Published: January 2006

In this study, we demonstrate the usefulness of chemical‐based method in combination with atomic force microscopy (AFM) to characterize the degradable regions in a wide range of polymer blends. This approach is based on selective hydrolysis of one of the components in a multiple‐phase system, and the ability of AFM to provide nanoscale lateral information about the different phases in the polymer system. Composite films containing different percentage of hydrolyzable polymer were either melt processed or solution casted and then exposed to a hydrolytic acidic environment. Tapping mode AFM was used to analyze the samples before and after hydrolysis. Dramatic topographic changes such as pits were observed on the acid exposed samples, indicating that the degradation was localized and the more susceptible component in the blend was hydrolyzed. Additionally, the progressive hydrolysis of the composites was studied by attenuated total reflection FTIR (ATR‐FTIR) analyses to confirm the AFM results. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 726–733, 2006
Synthesis and Preliminary Biological Evaluation of 2′‐Substituted 2‐(3′‐Carboxybicyclo[1.1.1]pentyl)glycine Derivatives as Group I Selective Metabotropic Glutamate Receptor Ligands
Authors: Pellicciari Roberto , Filosa Rosanna , Fulco Maria Carmela , Marinozzi Maura , Macchiarulo Antonio , Novak Clemens , Natalini Benedetto , Hermit Mette Brunsgaard , Nielsen Søren , Sager Thomas Nikolaj , Stensbøl Tine Bryan , Thomsen Christian
Published: January 2006

The first series of 2′‐substituted 2‐(3′‐carboxybicyclo[1.1.1]pentyl)glycine derivatives, (2R)‐ and (2S)‐(2′,2′‐dichloro‐3′‐carboxybicyclo[1.1.1]pentyl)glycine (10) and (11), and 2‐(2′‐chloro‐3′‐carboxybicyclo[1.1.1]pentyl)glycine (12) were synthesized and evaluated as mGluR ligands. Compounds 11 and 12 were shown to be competitive group I mGluR antagonists. These results are also discussed in light of docking studies with both the active (closed) and inactive (open) conformations of mGluR1.
Visual adaptations in the night‐active wasp Apoica pallens
Authors: Greiner Birgit
Published: January 2006

The apposition compound eye of the nocturnal polistine wasp Apoica pallens shows, in comparison to the closely related diurnal wasp Polistes occidentalis, specific adaptations to vision at low light intensities. When considering recent work on nocturnal and diurnal bees, general principles for dim‐light vision in hymenopterans become evident: The rhabdom diameters in nocturnal bees and wasps are 4 times wider compared to their diurnal relatives, leading to wide receptive fields, which in turn account for a 25‐fold higher optical sensitivity. Interestingly, the rhabdom diameters in both nocturnal bees and wasps measure 8 μm, which may represent the maximum width for nocturnal hymenopteran apposition eyes. A ratio of 1.8 times larger eyes is present in the nocturnal bees and wasps, which in A. pallens is achieved by increasing the facet number, instead of enlarging the facets, as in nocturnal bees. Although this initially indicates spatial resolution to be important for the nocturnal wasp, the wide receptive fields of the rhabdoms will reduce its potentially high acuity. As the optical sensitivity alone cannot account for the 8 log units intensity difference between day and night, a possible role of neural summation within the first optic ganglion (lamina) of nocturnal hymenopterans is discussed. J. Comp. Neurol. 495:255–262, 2006. © 2006 Wiley‐Liss, Inc.