bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cadmium telluride PV module manufacturing at BP Solar
Authors: Cunningham D. , Rubcich M. , Skinner D. 
Published: August 2002

AbstractBP Solar has built a 10 MW capacity CdTe thin‐film (Apollo®) manufacturing plant in Fairfield, California. The plant is on the verge of commercialization and is expected to produce several megawatts of 61 × 155 cm (24 × 61‐inch) thin‐film modules (nominally 80 W) in 2001. This paper describes the basic Apollo® process steps, the recent advances made in the Apollo® CdTe technology, the state of the art CdTe reactor with its sophisticated design and control features and various techniques used to characterize the semiconductor materials. Module performance and reliability results are also summarized. An NREL‐confirmed module efficiency of 10.6% is reported for a 0.94 m2 module with a maximum power of 91.5 W. Indoor stress testing and outdoor performance test beds are described, and the data presented show good indoor stability under various stress conditions. Copyright © 2002 John Wiley & Sons, Ltd.
Evaluation of the peacemakers program: School‐based violence prevention for students in grades four through eight
Authors: Shapiro Jeremy P. , Burgoon Joella D. , Welker Carolyn J. , Clough Joseph B. 
Published: August 2002

AbstractThis study evaluated the violence prevention effects of The Peacemakers Program, a school‐based intervention for students in grades four through eight. The program includes a primary prevention component delivered by teachers and a remedial component implemented by school psychologists and counselors with referred students. The teacher‐delivered component consists of a psychoeducational curriculum and procedures for infusing program content into the school environment. The study included almost 2,000 students in an urban public school system, with pre‐ and post‐program assessment and comparison to a control group. There were significant, positive program effects on six of the seven variables assessed, including knowledge of psychosocial skills, self‐reported aggression, and teacher‐reported aggression, with a 41% decrease in aggression‐related disciplinary incidents and a 67% reduction in suspensions for violent behavior. On some outcome variables, intervention effects were stronger for boys than girls and for middle school compared to upper elementary school students. © 2002 John Wiley & Sons, Inc.
Sequential poly(ester amide)s based on glycine, diols, and dicarboxylic acids: Thermal polyesterification versus interfacial polyamidation. Characterization of polymers containing stiff units
Authors: Asín L. , Armelin E. , Montané J. , Rodríguez‐Galán A. , Puiggalí J. 
Published: August 2002

AbstractSequential poly(ester amide)s derived from glycine were synthesized by a two‐step method, involving a final thermal polyesterification. Molecular weights were in general higher than those obtained with the previously reported synthesis on the basis of interfacial polyamidation. Polymers with stiff units like oxaloyl or terephthaloyl residues were thermally characterized and their degradability studied by using different types of enzymes. Polymers containing short diols are degradable in papain solutions, the degradation rate being higher for oxalic derivatives. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 4283–4293, 2001
Synthesis of statistical glycidyl methacrylate‐n‐vinyl pyrrolidone copolymers and their reaction with naproxen
Authors: Sánchez‐Chaves Manuel , Martínez Gerardo , López Madruga Enrique , Fernández‐Monreal Carmen 
Published: August 2002

AbstractFree‐radical copolymerization of glycidyl methacrylate (GMA) with N‐vinylpyrrolidone (VPD) was carried out at 50 °C using 3.0 mol · L−1 of N,N′‐dimethylformamide solution and 9.0 · 10−3 mol · L−1 of 2,2′‐azobisisobutyronitrile as an initiator. The modification reaction of GMA‐VPD copolymers with a model bioactive carboxylic acid, 6‐methoxy‐α‐methyl‐2‐naphthaleneacetic acid (naproxen), was studied in the homogeneous phase using basic catalysts. The influence of the type of catalyst and the GMA content was evaluated. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 1192–1199, 2002
Evaluation of compatibility and properties of biodegradable polyester blends
Authors: John Jacob , Mani Ramaswamy , Bhattacharya Mrinal 
Published: August 2002

AbstractThree different biodegradable polyesters, namely, polycaprolactone (PCL), polybutylene succinate (BIONOLLE), and a copolyester of adipic acid, terephthalic acid, and 1,4‐butanediol (EASTAR) were melt‐blended using a twin‐screw extruder. The percentage composition of each of the aforementioned polymers was varied to obtain different blends, and the mechanical properties were evaluated. Selected blends showed significant improvement in tensile strength as compared with the individual polymers used to prepare the blend. The compatibility between the polymer phases was examined via Fourier transform infrared (FTIR) and nuclear magnetic resonace (NMR) spectroscopy as well as dynamic mechanical analysis. FTIR and NMR data confirmed the occurrence of hydrogen‐bonding and ester‐interchange reactions. Thermal properties and changes in crystallinity of the blends were examined with differential scanning calorimetry and X‐ray diffraction. A considerable increase in crystallinity was shown by the blend system containing BIONOLLE/PCL. The morphology of the blends was observed and correlated to the improved mechanical properties of the blend system. Results revealed an intermediate multiphase system in which a significant degree of mixing was achieved through the chemical interaction of the functional groups present, while using the twin‐screw extruder. Significant improvement in mechanical properties of some blends was observed, and information about the miscibility of these polyesters is provided. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 2003–2014, 2002
Copper(I)‐mediated radical polymerization of methacrylates in aqueous solution
Authors: Perrier Sébastien , Armes Steven P. , Wang X. S. , Malet F. , Haddleton David M. 
Published: August 2002

Abstractα‐Methoxypolyethylene oxide methacrylate was polymerized by copper(I)‐mediated living radical polymerization in aqueous solution to give polymers with controlled number‐average molecular masses and narrow polydispersities. When equimolar quantities of initiator with respect to copper(I) bromide were used, the reaction was extremely fast with quantitative conversion achieved in less than 5 min at ambient temperature. However, the molecular weight distribution was broad, and control over the number‐average molecular weight (Mn) growth was extremely poor; this is ascribed to an increase in termination because of the increased rate as a result of the coordination of water at the copper center. The complex formed between copper(I) bromide and N‐(n‐propyl)‐2‐pyridylmethanimine, bis[N‐(n‐propyl)‐2‐pyridylmethanimine]copper(I), was demonstrated to be stable in aqueous solution by 1H NMR over 10 h at 25 °C. However, on increasing the temperature to 50 °C, decomposition occurred rapidly. Thus, polymerization temperatures were maintained at ambient temperature. When longer alkyl chains were utilized in the ligand, that is, pentyl and octyl, the complex acted as a surfactant leading to heterogeneous solutions. When the catalyst concentration was reduced by two orders of magnitude, the rate of polymerization was reduced with 100% conversion achieved after 60 min with the Mn of the final product being higher than that predicted and the polydispersity equal to 1.43. Copper(II) was added as an inhibitor to circumvent these problems. When 10% of Cu(I) was replaced by Cu(II) {[Cu(I)] + [Cu(II)]/[I] = 1/100}, the mass distribution showed a bimodal distribution, and the rate of polymerization decreased significantly. With a catalyst composition [Cu(I)]/[Cu(II)] = 0.5/0.5 {[Cu(I)] + [Cu(II)]}/[I] = 1/100, polymerization proceeded slowly with 80% conversion reached after 22 h. Thus, the concentration of Cu(I) was further reduced with [Cu(I)]/[Cu(II)] = 10/90, {[Cu(I)] + [Cu(II)]}/[I] = 1/100. The system then contained [Initiator]/[Cu(I)] = 1000/1 and [I]/[Cu(II)] = 1000/9. Under these conditions, the reaction reached 50% after 5 h with the polymer having both an Mn close to the theoretical value and a narrow polydispersity of PDi = 1.15. Optimum results were obtained by increasing the amount of catalyst. When a ratio of [Cu(I)]/[Cu(II)] = 10/90 with a ratio of [Cu]/[I] = 1/1, a conversion of 100% was achieved after less than 20 h, leading to a product having Mn = 8500 and PDi = 1.15. Decreasing the amount of Cu(II) relative to Cu(I) to [Cu(I)]/[Cu(II)] = 0.5/0.5 (maintaining the overall amount of copper) led to 100% conversion after 75 min: Mn = 9500, PDi = 1.10. Block copolymers have been demonstrated by sequential monomer addition with excellent control over Mn and PDi. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 1696–1707, 2001
Poly(pyridinium salt)s with stilbene or distyrylbenzene chromophores
Authors: Spiliopoulos Ioakim K. , Mikroyannidis John A. 
Published: August 2002

AbstractA new series of poly(pyridinium salt)s that contained side stilbenyl groups or p‐distirylbenzene segments in the main chain were synthesized from the reactions of bis(pyrylium salts) with diamines. They were characterized by viscometry, Fourier transform infrared spectroscopy, NMR, X‐ray scattering, differential scanning calorimetry, thermomechanical analysis, ultraviolet–visible analysis, and luminescence spectroscopy. The polymers were amorphous and soluble in polar aprotic solvents such as dimethylacetamide, dimethylformamide, and dimethyl sulfoxide. The glass‐transition temperatures were in the range of 59–123 °C. These polymers had initial decomposition temperatures of 240–295 °C and afforded anaerobic char yields of 29–53% at 800 °C. Both the absorption and photoluminescence (PL) spectra of the polymers were studied, and the PL quantum yields in solution were determined. The polymers showed violet‐blue fluorescence in solution with PL maxima at 408–416 nm and violet‐green fluorescence in thin film with PL maxima at 454–523 nm. The structure of the diamine utilized for the preparation of the polymers did not influence their PL maxima. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 2454–2462, 2001
Copolymerization of carbon dioxide and propylene oxide with Ln(CCl3COO)3‐based catalyst: The role of rare‐earth compound in the catalytic system
Authors: Liu Binyuan , Zhao Xiaojiang , Wang Xianhong , Wang Fosong 
Published: August 2002

AbstractA highly alternative copolymer of carbon dioxide and propylene oxide was obtained using a lanthanide trichloroacetates‐based ternary catalyst. The rare‐earth compound in the ternary catalyst was critical to dramatically raise the yield and molecular weight of the copolymer in addition to maintaining a high alternating ratio of the copolymer. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 2751–2754, 2001
Optical properties and orientation in polyethylene blown films
Authors: Bafna Ayush , Beaucage Gregory , Mirabella Francis , Skillas George , Sukumaran Satish 
Published: August 2002

AbstractWe report structural factors affecting the optical properties of blown polyethylene films. Two types of blown polyethylene films of similar degrees of crystallinity were made from (1) single‐site‐catalyst high‐density polyethylene (HDPE; STAR α) and (2) Ziegler–Natta‐catalyst HDPE (ZN) resins. The STAR α film exhibited high clarity and gloss, whereas the ZN film was turbid. Small‐angle X‐ray scattering (SAXS), small‐angle light scattering (SALS), and optical microscopy gave quantitative and qualitative information regarding structure and orientation in the films. A new approach is described for determining the three‐dimensional lamellar normal orientation from SAXS. Both the clear STAR α and turbid ZN films had similar lamellar crystalline structures and long periods but displayed different degrees of orientation. It is demonstrated that optical haze is related to surface features that seem to be linked to the bulk morphology. The relationship between haze and structural orientation is described. The lamellar orientation is linked to rodlike structures seen in optical microscopy and SALS through a stacked lamellar or cylindrite morphology on a nanometer scale and through a fiberlike morphology on a micrometer scale. The micrometer‐scale, rodlike structures seem directly related to surface roughness in a comparison of index‐matched immersion and surface micrographs. The higher haze and lower gloss of the ZN film was caused by extensive surface roughness not observed in the STAR α film. © 2001 John Wiley & Sons, Inc. J Polym Sci Part B: Polym Phys 39: 2923–2936, 2001
X‐ray photoelectron spectroscopy study of oxygen‐containing polymer [poly(vinyl methyl ether), poly(vinyl methyl ketone), and poly(methyl methacrylate)] surfaces metalized by vacuum‐deposited nickel
Authors: Bébin Philippe , Prud'Homme Robert E. 
Published: August 2002

AbstractSurfaces of poly(vinyl methyl ether) (PVME), poly(vinyl methyl ketone) (PVMK), and poly(methyl methacrylate) (PMMA) were covered with different thicknesses of nickel with a metal‐vapor‐condensation method, and the metal–polymer interfaces were analyzed by X‐ray photoelectron spectroscopy. In the very first steps of the metalization, it was found that a systematic degradation of the polymer surface occurs through CO or CO2 losses, depending on the polymer functionalities. Then, at the interface with the polymer, the condensed metal reacts by oxidization with the oxygen atoms that are still available after the surface degradation. Nickel oxide is then formed at the interface, whatever the nature of the initial polymer functional group. These new oxide species are not chemically bonded to the polymer structure, and their formation is not affected by the type of bond existing between oxygen and carbon atoms in the original polymer. Finally, the accumulation of metal on the substrate induces an amorphization of the polymer carbon structure because thermal energy is transferred from the metal coating to the polymer. © 2001 John Wiley & Sons, Inc. J Polym Sci Part B: Polym Phys 40: 82–94, 2002
Polypropylene/talc composites modified by a succinyl‐fluorescein grafted atactic polypropylene: A thermal and mechanical study under dynamic conditions
Authors: García‐Martínez J. Ma. , Laguna O. , Areso S. , Collar E. P. 
Published: August 2002

AbstractThis article reports on the interfacial modifications induced by different amounts of a succinyl‐fluorescein grafted atactic polypropylene (a‐PP‐SF) as a truly interfacial agent in polypropylene/talc composite materials. The a‐PP‐SF used, which contains 4% grafts, was previously obtained in our laboratory by chemical modification of a byproduct from industrial polymerization reactors. Thermal and mechanical analyses of composites, performed under dynamic conditions, led to the correlation of parameters at the microscopic scale with others at the macroscopic scale. Thus, the interfacial effect caused by different amounts of a‐PP‐SF in the composite can be concluded by observations made at either scale. © 2002 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 40: 1371–1382, 2002
Confirmation of the crystal structure of poly(p‐phenylene benzobisoxazole) by the X‐ray structure analysis of model compounds and the energy calculation
Authors: Tashiro Kohji , Hama Hisakatsu , Yoshino Jun‐Ichi , Abe Yukihiro , Kitagawa Tooru , Yabuki Kazuyuki 
Published: August 2002

AbstractTo check the previously proposed crystal structure of poly(p‐phenylene benzobisoxazole) [PBO], we performed an X‐ray structure analysis for single crystals of low molecular weight model compounds with the following chemical formulas:
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Both of these two model compounds show essentially the same molecular and subcell structures as those of PBO: the molecular chains take an almost perfect planar conformation and are packed together with a relative height between the adjacent chains of about 3 Å along the chain axis, although for the polymer the chains are shifted by the same value but in a disordered mode with respect to the direction of the shift (upward or downward), different from the regular packing in model compounds. These structural features are reproduced well with energy calculations. Structural ordering in PBO fibers caused by heat treatment at high temperatures, as clarified by X‐ray diffraction measurement, are interpreted on the basis of the energy calculations. © 2001 John Wiley & Sons, Inc. J Polym Sci Part B: Polym Phys 39: 1296–1311, 2001
Melt properties and crystal morphology of polydodecamide plasticized by benzenesulfonamides
Authors: De Groote Ph. , Jonas A. M. , Devaux J. , Godard P. 
Published: August 2002

AbstractThe melt of polydodecamide (PA‐12) shows a significant viscosity decrease upon incorporation of benzenesulfonamide plasticizers (BSAs), this effect being maximum for a monofunctional BSA with a 12‐carbon‐atom‐long alkyl chain. Nonexhaustive X‐ray diffraction analysis developed on isothermally crystallized samples validated a two‐phase model for describing PA‐12 plasticized by N‐(n‐butyl)benzenesulfonamide (BBSA). The massive presence of BBSA between the lamellar crystals was established, and lamellar fragmentation was also observed. Further, a steady increase in PA‐12 crystallinity with an increasing BBSA content was evident (and confirmed by DSC) and is consistent with the plasticizer easing the mobility of polymer chains during crystallization. Large melting point depressions resulting from both polymer–plasticizer miscibility and lamellar fragmentation were observed with several mono‐ and bifunctional BSA plasticizers. Phase separation in PA‐12 solid state was only observed at 20 mol % of ϕSO2NH2, alhough miscibility occurred in the melt. © 2001 John Wiley & Sons, Inc. J Polym Sci Part B: Polym Phys 39: 2022–2034, 2001
Crystallization kinetics and crystallization behavior of syndiotactic polystyrene/clay nanocomposites
Authors: Tseng Chen‐Rui , Lee Hsin‐Yi , Chang Feng‐Chih 
Published: August 2002

AbstractWe investigated the effects of montmorillonite (clay) on the crystallization kinetics of syndiotactic polystyrene (sPS) with isothermal differential scanning calorimetry analyses. The clay was dispersed into the sPS matrix via melt blending on a scale of 1–2 nm or up to about 100 nm, depending on the surfactant treatment. For a crystallization temperature of 240 °C, the isothermal crystallization data were fitted well with the Avrami crystallization equation. Crystallization data on the kinetic parameters (i.e., the crystallization rate constant, Avrami exponent, clay content, and clay/surfactant cation‐exchange ratio) were also investigated. Experimental results indicated that the crystallization rate constant of the sPS nanocomposite increased with increasing clay content. The clay played a vital role in facilitating the formation on the thermodynamically more favorable all‐β‐form crystal when the sPS was melt‐crystallized. © 2001 John Wiley & Sons, Inc. J Polym Sci Part B: Polym Phys 39: 2097–2107, 2001
Effect of pacifier use on oral breathing in healthy newborn infants
Authors: Cozzi Francesco , Morini Francesco , Tozzi Claudio , Bonci Enea , Cozzi Denis A. 
Published: August 2002

AbstractWe tested the hypothesis that the use of a pacifier may affect the ability of some term infants to maintain effective oral breathing during prolonged nasal occlusion. Three nasal occlusion tests without a pacifier and 3 with a pacifier were alternately carried out in 20 healthy term infants (age 2–5 days). Once the infant commenced oral breathing, nasal occlusion was continued for up to 90 sec (prolonged nasal occlusion), provided the infant did not start crying and that arterial oxygen saturation (SaO2) did not drop to ≤ 80%. The response to nasal occlusion was considered maladaptive if oral breathing was accomplished with signs of upper airway obstruction.After nasal occlusion, the infants succeeded in starting oral breathing in all instances after a delay which was strongly correlated to the drop in SaO2 (P < 0.001). Once the infants commenced oral breathing, 17/20 infants presented a maladaptive response to 62% of all tests without pacifier, whereas 10/20 infants presented a maladaptive response to 30% of all tests with a pacifier in place (P < 0.001). Following prolonged nasal occlusion, 18 of 19 infants presented a maladaptive response to 84% of all tests without pacifier, whereas 12 of 19 infants presented a maladaptive response to 41% of all tests with a pacifier in place (P < 0.001). Thus, after prolonged nasal occlusion with or without pacifier, the drop in mean SaO2 from baseline values changed in accordance with an appropriate and maladaptive response (−4 ± 1 vs. −7 ± 1; P < 0.001).We conclude that normal term infants often present with a maladaptive response to prolonged nasal occlusion. The use of a pacifier enhances the infant's ability to maintain a more adequate oral air flow. Pediatr Pulmonol. 2002; 33:368–373. © 2002 Wiley‐Liss, Inc.
Caspase‐8 activation is necessary but not sufficient for tumor necrosis factor‐related apoptosis‐inducing ligand (TRAIL)‐mediated apoptosis in the prostatic carcinoma cell line LNCaP
Authors: Rokhlin Oskar W. , Guseva Natalya V. , Tagiyev Agshin F. , Glover Rebecca A. , Cohen Michael B. 
Published: August 2002

AbstractBACKGROUNDThe differential sensitivity of tumor cells to TRAIL‐induced apoptosis may be mediated by different intracellular inhibitors of apoptosis, and only a few reports have described the pathway(s) that are activated in response to TRAIL in prostate cells.METHODSLNCaP was transfected with a dominant‐negative form of FADD (FADD‐DN) and cells were selected in the presence of hygromycin. Cell viability was estimated by calcein assay. Apoptosis was estimated by caspase activation using both fluorogenic substrastes and Western blot analysis of activated caspases. To detect cytochrome c release, mitochondria‐free cytosol was prepared and Western blot analysis was performed.RESULTSLNCaP is resistant to TRAIL but TRAIL transiently induces DEVDase activity and activation of caspase‐8; caspase‐2, ‐3, ‐7, and ‐9 were not activated. Wortmannin, an inhibitor of the PI3K/Akt pathway, converted the phenotype of LNCaP from TRAIL‐resistant to ‐sensitive. In the presence of wortmannin TRAIL induced activation of caspase‐2, ‐3, ‐7, ‐8, and ‐9, as well as dissipation of mitochondrial transmembrane potential and release of cyto‐chrome c from mitochondria into the cytosol. In addition, combined TRAIL and wortmannin treatment resulted in cleavage of several proteins: PARP, Akt, p21/WAF1, and MDM2 as well as dephosphorylation of Akt. The proteolysis of p21/WAFI and Akt, which are known survival factors, presumably amplify the apoptotic cascade in LNCaP. Transfection of FADD‐DN in LNCaP resulted in inhibition of caspase activation as well as in resistance to combined treatment with TRAIL and wortmannin.CONCLUSIONSThese results suggest that caspase‐8 activation is necessary but not sufficient for TRAIL‐mediated apoptosis and is presumably blocked downstream of caspase‐8 by the PI3K/Akt pathway. Prostate 52: 1–11, 2002. © 2002 Wiley‐Liss, Inc.