bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis of SiO2/PS composite particles via emulsion polymerization
Authors: Han Zhaorang , Wang Li , Zhu Jianmin , Zhang Shufen , Zhou Wei 
Published: April 2011

AbstractSiO2 particles prepared by Stöber method were modified using 1,3,5,7‐tetravinyl‐1,3,5,7‐tetramethylcyclotetrasiloxane (Vi‐D4), and SiO2/polystyrene (PS) composite particles with core‐shell structure were synthesized adopting mulsion polymerization of PS in a water–ethanol medium. The products were characterized by infrared spectra, X‐ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), and Zetasizer analyzer. The average diameter of SiO2 particles prepared by Stöber method was about 80 nm, the SiO2 particles were modified using the molar ratio of Vi‐D4 and SiO2 particles 1 : 10 (the dosage of Vi‐D4 benever too much), and the size of modified silica particles was about 90 nm. The infrared spectra indicated that the Vi‐D4 had bonded to the silanol groups on surface of SiO2 particles, and XPS indicated the grafting efficiency of Vi‐D4 on surface of SiO2 particles had reached 90%. The infrared spectra indicated the PS had been incorporated with SiO2 particles, and TEM indicated the composite particles have obvious core‐shell structure. The suitable size of SiO2 particles should be lower than 200 nm, and the optimum volume ratio of ethanol and water should be 1 : 9 or 1 : 4. A kind of monodisperse SiO2/PS composite particles having function of self‐assembling was successfully and effectively synthesized. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Modification of linear low‐density polyethylene film using oxygen scavengers for its application in storage of bun and bread
Authors: Matche Rajeshwar S. , Sreekumar R. K. , Raj Baldev 
Published: April 2011

AbstractLinear low‐density polyethylene (LLDPE) film was modified by blending with zinc, iron, or ascorbic acid as oxygen scavenger. The modified films were characterized for their physicomechanical properties and their application for oxygen scavenging. There was no significant change in the physicomechanical properties. The oxygen scavenging property of the films was studied by shelf‐life studies of bun and bread. The shelf life studies were conducted using the modified films and LLDPE film as a control. The sensory analysis showed good taste and texture of bun and bread till the fifth day. The control sample was not acceptable even on second day. This was supported by instrumental texture analysis. There was no significant change in force required to compress the sample in case of packed scavenging film while the control sample showed significant change. The moisture analysis also showed similar results. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Crystallization and melting behavior of biodegradable poly(ethylene succinate‐co‐6 mol % butylene succinate)
Authors: Yang Yan , Qiu Zhaobin 
Published: April 2011

AbstractThe crystallization, melting behavior, and spherulitic growth kinetics of biodegradable poly(ethylene succinate‐co‐6 mol % butylene succinate) [P(ES‐co‐6 mol % BS)] were investigated and compared with those of the homopolymer poly(ethylene succinate) (PES) in this work. The crystal structure of P(ES‐co‐6 mol % BS) was the same as that of neat PES, but the crystallinity decreased slightly because of the incorporation of the butylene succinate content. The glass‐transition temperature decreased slightly for P(ES‐co‐6 mol % BS) compared to that for neat PES. The melting point of P(ES‐co‐6 mol % BS) decreased apparently; moreover, the equilibrium melting point was also reduced. Two melting endotherms were found for P(ES‐co‐6 mol % BS) after isothermal crystallization; this was ascribed to the melting, recrystallization, and remelting mechanism. The spherulitic growth rate of P(ES‐co‐6 mol % BS) was slower than that of neat PES at a given crystallization temperature. Both neat PES and P(ES‐co‐6 mol % BS) exhibited a crystallization regime II to III transition; moreover, the crystallization regime transition temperature of P(ES‐co‐6 mol % BS) shifted to a low temperature compared with that of neat PES. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Preparation and thermal response behavior of poly(N‐isopropylacrylamide‐co‐a crylic acid) microgels via soap‐free emulsion polymerization based on AIBN initiator
Authors: Chen Shufan , Jiang Long , Dan Yi 
Published: April 2011

AbstractPoly(N‐isopropylacrylamide‐co‐acrylic acid) (poly(NIPAM‐co‐AA)) microgels with different copolymer compositions were prepared through soap‐free emulsion polymerization at 80°C, and 2, 2′‐azobisisobutyronitrile (AIBN) was used as initiator. Scanning electron microscope (SEM) characterization shows that the prepared microgels are regular and smooth and not easy to distort. Result of 1H‐NMR characterization shows that with increasing of the initial concentration of AA (AA in feed), the AA content in polymer chains increases. The thermal response of microgels latex was investigated by UV‐3010 spectrophometer through detecting the transmittance of the latex at different temperature in the range of 190–900 nm. The thermal response of the poly(NIPAM‐co‐AA) microgels was tested by dynamic light scattering (DLS). The results show that with the increase of AA content in polymer chains, the low critical solution temperature (LCST) of microgels latex first decreases and then increases. Still, with increasing of AA in poly(NIPAM‐co‐AA) microgels, the LCST of microgels first increases and then decreases. The basic reasons causing the changes of LCST of microgels latex and microgels are interpreted clearly in this article from the perspective of hydrogen bonding interaction. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Synthesis and characterization of tetrakis‐ derivatives of bisphenol‐A with 4‐phenylazoaniline and 5‐(4‐aminophenylazo)‐25,26,27‐tribenzoyloxy‐ 28‐hydroxycalix[4]arene
Authors: Karakuş Özlem Özen , Deligöz Hasalettin 
Published: April 2011

AbstractThe synthesis of tetrakis‐ derivatives of bisphenol‐A containing azo groups at their 2,2′,6,6′‐positions is reported. Novel examples of bisphenol‐A, coupled with diazonium salts and derived from 4‐phenylazoaniline and 5‐(4‐aminophenylazo)‐25,26,27‐tribenzoyloxy‐28‐hydroxycalix [4]arene, have been synthesized. It has been observed that the coupling reaction of diazonium salt obtained from 4‐phenylazoaniline with bisphenol‐A gives tetrakis‐ while those derived from 5‐(4‐aminophenylazo)‐25,26,27‐tribenzoyloxy‐28‐hydroxycalix [4]arene give partially substituted bisphenol‐A analogues. The newly prepared tetrakis‐azo substituted bisphenol‐A compounds (1 and 2) are characterized by using UV‐vis, FT‐IR, 1H‐NMR spectroscopic methods as well as elemental analysis techniques. These azo compounds give rise to bathochromic shifts in the absorption spectra, which can even be detected by “naked eye.” © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Use of rosin‐based nonionic surfactants as petroleum crude oil sludge dispersants
Authors: Atta Ayman M. , Elsaeed Ashraf M. 
Published: April 2011

AbstractThe present work provides better knowledge for composition analyses of the sludge and evaluates the best effective and economical treatment of petroleum sludge. In this respect, nonionic polymeric surfactants based on rosin were prepared by esterification of rosin with different molecular weights of polyethylene glycol (PEG 400, 600, 1000, 2000) to produce rosin ester surfactants. The esterified rosin was reacted with maleic anhydride followed by reaction with diaminobutane or triethylene tetramine to produce rosin‐imide. The products were etherified with PEG 600 and PEG 2000 to produce rosin‐imide ERID‐1, ERID‐2, ERIT‐1 and ERIT‐2, which were characterized by FT‐IR and 1H‐NMR analyses. The surfactants were tested as sludge dispersants from viscosity measurements of sludge crude oil mixtures at different times. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Preparation of porous poly(3‐hexylthiophene) by freeze‐dry method and its application to organic photovoltaics
Authors: Huang Ping‐Tsung , Chang Yao‐Sheng , Chou Cheng‐Wei 
Published: April 2011

AbstractPoly(3‐hexylthiophene)(P3HT) with a microporous network structure was prepared from a 1% p‐xylene solution by freeze‐dry method. Scanning electron microscopy (SEM) showed P3HT molecules formed swollen gel‐like structures with different extent of compactness depending on the length of the aggregation period. Absorption spectrum of this P3HT film showed a characteristic peak at 620 nm, which indicated a high degree of order between polymer chains. Photoluminescence (PL) of this highly ordered P3HT film appeared at 712 nm revealing large extent of π–π stacking between P3HT molecules in the freeze‐dry film. Both absorption and photoluminescence results indicated that the original aggregated states of P3HT molecules in gel form had been preserved throughout the freeze‐dry operation. X‐ray diffraction of the annealed samples showed a strong characteristic peak for the side chain aggregation at 2θ = 5.1°, which proved that the freeze‐dry film was with highly order structure. The interconnected and highly ordered P3HT film is used in the study of organic photovoltaics (OPV) after applying an n‐type semiconductor to the surface of the dry porous fibers. A prototype OPV device with power conversion efficiency of 1.47% was prepared by this method. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011.
Mechanism of seeded dispersion polymerization of methyl methacrylate using submicron polystyrene seed particles
Authors: Song Zhipeng , Daniels Eric S. , David Sudol E. , El‐Aasser Mohamed S. , Klein Andrew 
Published: April 2011

AbstractSubmicron polystyrene (PS) latex particles were used as seed in seeded dispersion polymerization of methyl methacrylate (MMA) to investigate the particle nucleation and aggregation behavior in this type of polymerization. The PS seed particles were located and tracked during the reaction using a refractive index matching technique. The number of PS seed particles present in the poly(methyl methacrylate) (PMMA) particles was investigated in detail throughout the reaction. The change in the distribution of PMMA particle populations containing different numbers of seed particles indicated that intensive nucleation and aggregation occurred during the early stage of the reaction until a transition point of 8.7% conversion was attained under the reaction conditions studied. The size of the large particles at this point was around 1 μm. These particles were regarded as mature particles that did not aggregate with other mature particles. Meanwhile, immature particle were still generated continuously from the continuous phase. These immature particles could not survive the aggregation process to grow to become mature particle, but instead, were captured by the mature particles. Therefore, the total number of the mature particles remained constant from this point until the end of the reaction. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Thermal and mechanical properties of stretched recyclable polyimide film
Authors: Wang Han‐Yi , Liu Ta‐Jo , Liu Shur‐Fen , Jeng Jhy‐Long , Guan Chi‐En 
Published: April 2011

AbstractAn operating window, which is bounded by two temperatures and draw ratios, defines the stable and defect‐free stretching region of a polymer film. Physical properties including the coefficient of thermal expansion (CTE), birefringence, and Young's modulus of a recyclable polyimide (PIR) film were measured under stretching conditions. While values of birefringence and Young's modulus increased with increasing stretching stress in the machine direction, the CTE was found to decrease. A semiempirical model for the prediction of birefringence and Young's modulus under stretching conditions was developed, from which the CTE could be estimated from the Young's modulus data. Theoretically evaluated physical properties were found to be in qualitative agreement with the experimental data. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Modification of nylon 66 by electron beam irradiation for improved properties and superior performances
Authors: Pramanik N. K. , Haldar R. S. , Bhardwaj Y. K. , Sabharwal S. , Niyogi U. K. , Khandal R. K. 
Published: April 2011

AbstractNylon 66 has been transformed into a material with significantly improved properties like hardness, tensile strength, and flexural modulus by processing it under the optimized dose rate of electron beam in the presence of suitable crosslinkers. Furthermore, percent water absorption of nylon 66 was reduced substantially on irradiation. Thermogravimetric analysis revealed that thermal stability of nylon 66 improved with increasing dose of radiation. Improvement of mechanical and thermal properties and reduction of water absorption of nylon 66 were due to the crosslinking of polyamide molecules made possible by the high energy radiation. Increase of crosslinking with increasing radiation dose was verified by the increase of gel content at higher doses. Differential scanning calorimetry showed that both melting and crystallization temperatures along with percent crystallinity of nylon 66 were decreased with the increasing dose of radiation leading to the development of more amorphous character in this semicrystalline polymer. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011.
Association of endogenous anti–interferon‐α autoantibodies with decreased interferon‐pathway and disease activity in patients with systemic lupus erythematosus
Authors: Morimoto Alyssa M. , Flesher Donna Thibault , Yang Jihong , Wolslegel Kristen , Wang Xiangdan , Brady Ann , Abbas Alexander R. , Quarmby Valerie , Wakshull Eric , Richardson Bruce , Townsend Michael J. , Behrens Timothy W. 
Published: April 2011

AbstractObjectiveNumerous observations implicate interferon‐α (IFNα) in the pathophysiology of systemic lupus erythematosus (SLE); however, the potential impact of endogenous anti‐IFNα autoantibodies (AIAAs) on IFN‐pathway and disease activity is unclear. The aim of this study was to characterize IFN‐pathway activity and the serologic and clinical profiles of AIAA‐positive patients with SLE.MethodsSera obtained from patients with SLE (n = 49), patients with rheumatoid arthritis (n = 25), and healthy control subjects (n = 25) were examined for the presence of AIAAs, using a biosensor immunoassay. Serum type I IFN bioactivity and the ability of AIAA‐positive sera to neutralize IFNα activity were determined using U937 cells. Levels of IFN‐regulated gene expression in peripheral blood were determined by microarray, and serum levels of BAFF, IFN‐inducible chemokines, and other autoantibodies were measured using immunoassays.ResultsAIAAs were detected in 27% of the serum samples from patients with SLE, using a biosensor immunoassay. Unsupervised hierarchical clustering analysis identified 2 subgroups of patients, IFNlow and IFNhigh, that differed in the levels of serum type I IFN bioactivity, IFN‐regulated gene expression, BAFF, anti–ribosomal P, and anti‐chromatin autoantibodies, and in AIAA status. The majority of AIAA‐positive patients had significantly lower levels of serum type I IFN bioactivity, reduced downstream IFN‐pathway activity, and lower disease activity compared with the IFNhigh patients. AIAA‐positive sera were able to effectively neutralize type I IFN activity in vitro.ConclusionPatients with SLE commonly harbor AIAAs. AIAA‐positive patients have lower levels of serum type I IFN bioactivity and evidence for reduced downstream IFN‐pathway and disease activity. AIAAs may influence the clinical course in SLE by blunting the effects produced by IFNα.
The associations between finger length pattern, osteoarthritis, and knee injury: Data from the Framingham community cohort
Authors: Haugen Ida K. , Niu Jingbo , Aliabadi Piran , Felson David T. , Englund Martin 
Published: April 2011

AbstractObjectiveTo investigate the associations of index finger–to–ring finger (2D:4D) length ratio with radiographic knee and hand osteoarthritis (OA), previous knee injury, and meniscal lesions in the general population.MethodsWe measured the length of the right second and fourth phalangeal and metacarpal bones on hand radiographs from 1,020 randomly recruited subjects (ages 51–92 years). Knee radiography and magnetic resonance imaging (MRI) were performed on subjects. Women and men were divided into tertiles according to their 2D:4D phalangeal and metacarpal ratios. We assessed the odds ratios (ORs) and 95% confidence intervals (95% CIs) for radiographic knee OA, severe symptomatic knee OA, radiographic hand OA, previous knee injury, and MRI‐defined meniscal lesion, using logistic regression with adjustment for age and body mass index. Because hand OA may affect the 2D:4D phalangeal ratio, we performed sensitivity analyses in subjects without joint space narrowing in the second and fourth interphalangeal joints.ResultsWe found no significant associations between 2D:4D length ratio and radiographic knee OA, severe symptomatic knee OA, or meniscal lesions. Low 2D:4D phalangeal ratio was associated with hand OA in women (OR 1.80, 95% CI 1.11–2.93), but in the sensitivity analysis, the association was attenuated (OR 1.35, 95% CI 0.79–2.32). Low 2D:4D phalangeal ratios were associated with knee injury in men (OR 1.78, 95% CI 1.02–3.10). We found no significant associations for 2D:4D metacarpal ratios.ConclusionLow 2D:4D phalangeal ratios in men are associated with knee injury, but we did not find any significant association with knee OA. Low 2D:4D length ratio may be a consequence, rather than a cause, of hand OA in women.
Differential antiinflammatory and antinociceptive effects of the somatostatin analogs octreotide and pasireotide in a mouse model of immune‐mediated arthritis
Authors: Imhof Anne‐Katja , Glück Laura , Gajda Mieczyslaw , Lupp Amelie , Bräuer Rolf , Schaible Hans‐Georg , Schulz Stefan 
Published: April 2011

AbstractObjectiveClinical and preclinical evidence suggests that somatostatin exhibits potent antiinflammatory and antinociceptive properties. However, it is not known which of the 5 somatostatin receptor subtypes (SSTRs 1–5) is involved in these actions. The purpose of this study was to assess the effects of the stable somatostatin analogs octreotide and pasireotide (SOM230) in a mouse model of antigen‐induced arthritis (AIA).MethodsStudies were performed in SSTR2‐deficient mice (SSTR2–/–) and their wild‐type littermates (SSTR2+/+). The expression of SSTR1, SSTR2A, SSTR3, and SSTR5 in dorsal root ganglia was examined by immunohistochemistry.ResultsUntreated SSTR2–/– mice with AIA displayed joint swelling and mechanical hyperalgesia similar to that seen in SSTR2+/+ mice. In wild‐type mice, both octreotide and pasireotide significantly attenuated knee joint swelling and histopathologic manifestations of arthritis to an extent comparable to that of dexamethasone. In SSTR2–/– mice, the antiinflammatory effects of both octreotide and pasireotide were completely abrogated. Prolonged administration of pasireotide also inhibited joint swelling and protected against joint destruction during AIA flare reactions. In addition, both octreotide and pasireotide reduced inflammatory hyperalgesia. The antinociceptive actions of octreotide were abolished in SSTR2–/– mice, but those of pasireotide were retained. In dorsal root ganglia of naive wild‐type mice, only SSTR1 and SSTR2A, but not SSTR3 or SSTR5, were detected in a subset of small‐ and medium‐diameter neurons.ConclusionOur findings indicate that the antinociceptive and antiinflammatory actions of octreotide and pasireotide are largely mediated via the SSTR2 receptor. In addition, we identified the SSTR1 receptor as a novel pharmacologic target for somatostatin‐mediated peripheral analgesia in inflammatory pain.
Biomarkers of incident radiographic knee osteoarthritis: Do they vary by chronic knee symptoms?
Authors: Golightly Yvonne M. , Marshall Stephen W. , Kraus Virginia B. , Renner Jordan B. , Villaveces Andrés , Casteel Carri , Jordan Joanne M. 
Published: April 2011

AbstractObjectiveTo explore the ability of osteoarthritis (OA)–related biomarkers to predict incident radiographic knee OA in a large sample of African American and Caucasian men and women.MethodsBaseline levels of serum cartilage oligomeric matrix protein (COMP), hyaluronan (HA), high‐sensitivity C‐reactive protein (hsCRP), and keratan sulfate (KS) and baseline and followup radiographs were available for 353 knees without baseline osteophyte formation and for 446 knees without baseline joint space narrowing (JSN). Cox models estimated the hazard ratio (HR) and 95% confidence interval (95% CI) for incident knee OA for a 1‐unit increase in the ln of each biomarker, with adjustment for age, race, sex, body mass index, and knee OA of the contralateral limb. Report of chronic knee symptoms was explored as a modifier of the association.ResultsThe hazard of incident knee osteophytes (HR 2.16 [95% CI 1.39–3.37]) and incident JSN (HR 1.82 [95% CI 1.15–2.89]) increased with higher baseline ln(COMP) levels. The hazard of incident knee JSN increased with higher ln(HA) levels (HR 1.46 [95% CI 1.14–1.87]). Baseline ln(hsCRP) and ln(KS) did not predict incident knee outcomes. HRs per unit increase in ln(COMP), ln(HA), and ln(KS) were higher among knees with chronic symptoms than among those without symptoms.ConclusionHigher baseline ln(COMP) and ln(HA) levels were associated with incident knee OA over an average followup period of 6.3 years. These results represent detection of a molecular stage of OA prior to radiographic manifestations. Further exploration is needed to determine how chronic knee symptoms modify the biomarker–incident knee OA association.
Characterization of the anticollagen antibody response in a new model of chronic polyarthritis
Authors: Conigliaro Paola , Benson Robert A. , Patakas Agapitos , Kelly Sharon M. , Valesini Guido , Holmdahl Rikard , Brewer James M. , McInnes Iain B. , Paul Garside  
Published: April 2011

AbstractObjectiveType II collagen (CII)–specific B cell responses have been recognized in human rheumatoid arthritis (RA) and in collagen‐induced arthritis (CIA). An important limitation of the CIA model is that the CII response and the disease are stimulated by exogenously injected collagen. A model of experimental ovalbumin (OVA)–mediated acute arthritis has been established in which autoimmunity is spontaneous and elicited by antigen‐specific T cells. This study was undertaken to create a new model of chronic autoimmune polyarthritis and characterize the associated CII‐specific B cell response.MethodsSecondary challenge with OVA or CII in adjuvant was used to elicit chronic disease. CII‐specific B cell responses against the epitopes U1, J1, C1, and citrullinated C1, together with the antibody affinity, were investigated in OVA‐mediated arthritis.ResultsChronic autoimmune polyarthritis was induced and was dependent on the antigen used in the secondary challenge. U1 was the major CII epitope recognized, and antibodies showed the same affinity as those in CIA.ConclusionOur findings indicate that the development and severity of chronic disease is dependent on the antigen and is associated with an increased autoreactive B cell response directed against a specific CII epitope (U1). OVA‐mediated chronic arthritis exhibits anti‐CII antibodies (against U1), resembling human RA and murine CIA.