bluuebunny/crossref_metadata_2025_split huggingface dataset:
Particle size analysis of plasticized PVC dispersion resins using the photometric centrifugal sedimentation method
Authors: Moran Michael T. 
Published: December 2004

AbstractThere are many known methods for determining the particle size distribution of PVC dispersion resins. Most of these methods require that the resin be in an aqueous medium. PVC dispersion resins are used primarily in a plasticizer medium. The shearing action that takes place when the resin is mixed in plasticizer and the subsequent solvating action of the plasticizer affect the particle size distribution of the dispersion resin. It is advantageous to be able to determine the particle size distribution of the plasticized resin since it can affect various properties such as rheology, gloss and foam quality. It is the purpose of this paper to show that a fast zonal sedimentation technique can be used to analyze the less than 20 μ particle size fraction of a dispersion resin after it has been mixed in a plasticizer system. This can be accomplished in less than 90 minutes. This technique can be used to relate particular dispersion resin properties to the particle size distribution of the resin. The method can also be used as a quality control test.
Some viscoelastic porperties of poly(vinyl chloride)/dioctyl phthalate systems
Authors: Santamaria A. , Muñoz M. E. , Peña J. J. 
Published: December 2004

AbstractThe viscosty and the recoverable shear compliance of poly(viny chloride)/dioctyl phthalate systems are studied at different temperatures and concentrations. The recoverable shear compliance is determined by the method of the stress relaxation after cessation of flow in a Couette flow viscosimeter. The results show the existence of a concentration dependent critical temperature Tc which separates two different flow regions.
A scientific approach to rigid poly(vinyl chloride) extrusion
Authors: Summers James W. , Rabinovitch Elvira B. , Quisenberry Joseph G. 
Published: December 2004

AbstractAlthough rigid PVC has been extruded for many decades, more recent scientific evidence on primary particle flow units, crystalline structure, melting and recrystallization, transition from melt fracture to viscous flow, and differences in shear history between cubes and powder help to understand PVC extrusion. This understanding can replace some of the art of PVC extrusion with science. In this paper this science is applied to PVC extrusion, trouble shooting, scrap recovery, and property development.
Working party on defects in the molecular structure of polyvinylchloride and their relation to thermal stability: General introduction
Authors: Michel Alain 
Published: December 2004

AbstractMembership of the Working Party during 1977–83 is principally as follows: Chairman/secretary: A. Michel (France).Members: M.W. Allsopp (U.K.), V. Bellenger (France), J. Büssing (FRG), D. Braun (FGR), A.A. Caraculacu (Romania), E.A. Collins (USA), V. Dobrescu (Romania), K.F. Elgert (FRG), Z. Grubisic‐Gallot (France), A. Guyot (France), P. Kappler (France), T. Kelen (Hungary), M. Kolinsky (Czechoslovakia), C.J.M. Van den Heuvel (Netherlands), W.F. Maddams (U.K.), J.L. Millan (Spain), G. Palma (Italy), R. Panaras (France), G.S. Park (U.K.), Quang Tho Pham (France), U. Schwenk (FRG), P. Simak (FRG), E. Sörvik (Sweden), J.A.J.M. Vincent (Netherlands), D.E. Witenhafer (USA).
Working party on defects in the molecular structure of polyvinylchloride and their relation to thermal stability: General conclusions
Authors: Guyot Alain 
Published: December 2004

AbstractWith the purpose to correlate the thermal stability of PVC with its structural defects, a number of studies have been carried out on 13 PVC samples and in some cases on their fractions. These studies are dealt with structural determination on the one hand and thermal degradation tests on the other hand.
Suspension stabilizers for PVC production III: Control of resin porosity
Authors: Nilsson Holger , Silvegren Christer , Törnell Bertil , Lundqvist Jörgen , Pettersson Sven 
Published: December 2004

AbstractSuspension PVC resins were prepared using dispersant systems based on a cellulose derivative, Methocel F50, and two poly(vinyl alcohol)s; Gohsenol GH20 and Rhodoviol 5/270. Ammonium laurate and Span 20 were tested as secondary dispersants. The resins were characterized by mercury porosimetry. The results showed that the porosity of the resins increased in the series Gohsenol < Methocel < Rhodoviol. This order seems to follow the order of increasing surface activity. A closer analysis of the data clearly showed, however, that porosity control in S‐PVC manufacture is not due to a pure interfacial tension mechanism, not even in those cases where the dispersant systems do not contain any monomer‐soluble components. Other possible mechanisms by which suspension stabilizers may affect resin porosity are briefly commented upon.
Recovery of reusable poly(vinyl chloride) from plastics waste
Authors: Papaspyrides C. D. , Diakoulaki D. C. 
Published: December 2004

AbstractSolvent recycling of poly(vinyl chloride) (PVC), on the basis of the cyclohexanone/n‐hexane system, is further studied. By also using water during the washing stage, hexane quantities employed and solvents separation costs involved are drastically reduced. The modification proposed does not result in any alteration of the main characteristics of the process which further can be extended to rigid PVC pipes. No degradation effects were detected while the polymer recycled exhibits mechanical properties comparable with those of the virgin grade PVC especially with waste material of low additives content. Nevertheless, even from pipes, the polymer recovered proved quite suitable for similar applications.
Improving the processing properties of chlorinated PVC resins
Authors: Neuman R. C. , Swanson M. 
Published: December 2004

AbstractAn earlier paper (1) established the need for new compounding technology to deal with changes in melt flow resulting from the postchlorination of PVC resins. The present work attacks the more‐than‐doubled melt viscosity of chlorinated PVC as measured in stabilized resin. The potential for marked reduction in viscosity. improvement in processing stability, and retention of marketable product properties is explored. The development process including the definition of performance requirements, test methods used, and resulting balance of properties is described.
The function of lubricants in processing of rigid poly(vinyl chloride)
Authors: Bower J. David 
Published: December 2004

AbstractIn this review of lubricants and how they function the lubrication mechanism is broken down into three stages: the heat absorption (onset of gelation), gelation (fusion process), and melt flow (postfusion) stages. The terms “internal” and “external” are used to describe the functionality of the lubricant at each stage. It is pointed out that these terms should not be used to label lubricants themselves, because most lubricants perform differently at each stage of processing. How the chemical and physical properties of various types of lubricants perform in each of the fusion stages is also discussed.
The rheology of PVC
Authors: Driscoll Stephen Burke , Grolman Cory Peter 
Published: December 2004

AbstractA brief historical review has been made of rheological instrumentation developed for measuring the flow properties of vinyl materials. During this maturation of techniques the need for more complete flow characterizations spawned the development of dynamic mechanical instruments. These instruments provided convenient and accurate means of generating complex viscosity (n*) data composed of elastic (G′) and (G″) elements. Examples have been presented illustrating how these newer techniques are able to reliably provide critical data needed to control productivity and product performance properties. Extension of these techniques to on‐line rheometry has improved quality control link in the compounding operation.
An evaluation of the cavity transfer mixer for the extrusion of rigid PVC on both single and twin screw extruders
Authors: Gale G. M. 
Published: December 2004

AbstractPVC powder compound fed into single‐ and twin‐screw extruders retrofitted with cavity transfer mixers improved PVC grain fusion. Consequent improvements in appearance and properties ought to reduce current tight comprises that must be made between materials costs, output rate, and quality.
Melt flow behavior of blends from poly(vinyl chloride) and epoxidized natural rubber
Authors: Varughese K. T. , De P. P. , Nando G. B. , De S. K. 
Published: December 2004

AbstractBlends from poly(vinyl chloride) (PVC) and epoxidized natural rubber (ENR) were prepared in a Brabender plasticorder by the melt blending technique. The melt flow behavior of these blends with respect to blend ratio and temperature has been examined using a melt flow indexer and capillary rheometer. ENR decreases the Brabender torque, increases the melt flow index (MFI), and decreases the melt viscosity of PVC in the blends. Arrhenius plots were used to study the effect of temperature on melt flow index (MFI) and viscosity. Moreover, the flow behavior index (n′) obtained from capillary rheometer data was found to be dependent on temperature and blend ratio.
Paint primer system utilizing polyvinyl fluoride film
Authors: Bowley Michael W. 
Published: December 2004

AbstractA new generation of polyvinyl fluoride film has been specifically developed for use as a primer surface for automotive components which cannot otherwise be decorated with regular OEM paints, or where improved adhesion between the paint and the part is desired. Special film surface modifications provide for excellent adhesion between the film and a broad range of OEM and refinish paints. Lab and proving ground testing demonstrate solid performance throughout the exposure cycles required by FBMS 1–38. Current applications include vinyl and aluminum parts. The polyvinyl fluoride film is applied by lamination to extruded plastic or to coil stock using acrylic and acrylic/epoxy adhesives with proven outdoor durability. For parts subject to aggressive gravel attack, or where bonding to plastic parts is desired simply by heat fusion, a laminate of polyvinyl fluoride with a thin plastic face sheet can be used. Paints are applied according to normal operating procedures. This includes baking temperatures up to 300°F subject to the dimensional stability of the part. The chemical resistance of polyvinyl fluoride allows the use of virtually any chemical or solvent without attack to the film.
The nonyl phthalate ester and its use in flexible PVC
Authors: Wadey Brian L. , Thil Lucien , Khuddus Mo A. , Reich Hans , Ag Basf 
Published: December 2004

AbstractSix di‐nonyl phthalates varying in degree of branching are evaluated in both suspension and low soap plastisol resin formulations. Comparative plasticizer performance properties of these systems are studied in terms of plasticizer structural differences and their affects on processing parameters and physical properties of suspension resin and low soap dispersion resin formulations.
DSC analysis of fusion level of rigid PVC revisited: Filler effects on thermal analysis data
Authors: Choi P. , Lynch M. , Rudin A. , Teh J. W. , Batiste J. 
Published: December 2004

AbstractA DSC method for assessing degree of fusion of rigid PVC compounds has been improved, so as to make the technique more precise and objective. Analysis of conventional pipe samples provides assessments of gelation level that accord with solvent resistance and practical experience. However, thermal analysis techniques prove to be unreliable for compounds that contain no filler or more than about 13% filler. At least about 1% filler appears to be necessary for the phenomena that are the basis of this technique. Filler may affect crystallization of PVC compounds.
Absence of NF-κB Activation by a New Polystyrene-Type Adsorbent Designed for Hemoperfusion
Authors: Menegatti Elisa , Ronco Claudio , Winchester James F. , Dragonetti Antonella , Di Simone Debora , Davit Annalisa , Mengozzi Giulio , Marietti Giorgio , Loduca Giuseppina , Mansouri Morteza , Sancipriano Gian Piero , Sena Luigi M. , Roccatello Dario 
Published: December 2004

<i>Aim:</i> The aim of the study was to evaluate biocompatibility of anew polystyrene-type adsorbent (BetaSorb<sup>TM</sup>) designed for hemoperfusion, using second-level biomolecular analyses. The device has recently been developed to enhance β<sub>2</sub>-microglobulin removal during hemodialysis. Molecular structure and chemical modifications of the surface beads of this cartridge should prevent exposure of dense hydrophobic surface sites to proteins, and avoid the major drawbacks of previous polystyrene-type adsorbent materials. <i>Methods:</i> Whole blood of healthy donors was incubated in sterile minicolumns packed with BetaSorb Cuprophan, Hemophan, polysulfone and cellulose acetate. In parallel experiments, whole blood was recirculated for 180 min in a sham dialysis circuit equipped with the study sorbent or Hemophan or polysulfone. Biocompatibility was assessed by means of new biomolecular approaches focused on nuclear factor ĸB (NF-ĸB) activation (assessed by electrophoretic mobility shift assay), TNF-α and IL-1β gene expression (evaluated by real-time PCR), TNF-α and IL-1β production (measured by Western blot assay and ELISA), nitric oxide (NO) generation (detected by electron paramagnetic resonance), free oxygen radical production (by chemiluminescence in a biological assay) and the generation of the complement breakdown product C3d. <i>Results:</i>In coincubation experiments, 5-min contact with any dialysis device, but BetaSorb, was enough to induce activation of NF-ĸB. The amount of TNF-α precursor form was found to increase after 5 min of exposure to each tested polymer, but no traces of mature forms of TNF-α or IL-1β were detected in in vitro experimental conditions using healthy blood. NO and free oxygen radical generation were significantly lower in blood samples exposed to BetaSorb than in control dialysis devices. C3d levels were found to be increased with Hemophan, unaffected by polysulfone, and remarkably decreased with the BetaSorb device. In the sham hemodialysis experiments, NF-ĸB activation and C3d and NO profiles were similar to direct incubation experiments. Compared to basal levels, quantitation of TNF-α and IL-1β mRNA revealed a 15- and 9-fold increase, respectively, in samples exposed to Hemophan for 180 min. <i>Conclusions:</i> The new BetaSorb device not only appears to be highly biocompatible, but shares properties that make it probably able to interfere with the activation of the inflammatory state.
Stratospheric Influences on MSU-Derived Tropospheric Temperature Trends: A Direct Error Analysis
Authors: Fu Qiang , Johanson Celeste M. 
Published: December 2004

Abstract
Retrievals of tropospheric temperature trends from data of the Microwave Sounding Unit (MSU) are subject to biases related to the strong cooling of the stratosphere during the past few decades. The magnitude of this stratospheric contamination in various retrievals is estimated using stratospheric temperature trend profiles based on observations. It is found that from 1979 to 2001 the stratospheric contribution to the trend of MSU channel-2 brightness temperature is about −0.08 K decade−1, which is consistent with the findings of Fu et al. In the retrieval method developed by Fu et al. based on a linear combination of MSU channels 2 and 4, the stratospheric influence is largely removed, leaving a residual influence of less than ±0.01 K decade−1. This method is also found to be more accurate than the angular scanning retrieval technique of Spencer and Christy to remove the stratospheric contamination.
Clinical Model to Predict Survival in Chemonaive Patients With Advanced Non–Small-Cell Lung Cancer Treated With Third-Generation Chemotherapy Regimens Based on Eastern Cooperative Oncology Group Data
Authors: Hoang Tien , Xu Ronghui , Schiller Joan H. , Bonomi Philip , Johnson David H. 
Published: December 2004

Purpose (1) Identify clinical factors that can be used to predict survival in chemotherapy-naive patients with advanced non–small-cell lung cancer (NSCLC) treated with third-generation chemotherapy regimens, and (2) build a clinical model to predict survival in this patient population. Patients and Methods Using data from two randomized, phase III Eastern Cooperative Oncology Group (ECOG) trials (E5592/E1594), we performed univariate and multivariate stepwise Cox regression analyses to identify survival prognostic factors. We used 75% of randomly sampled data to build a prediction model for survival, and the remaining 25% of data to validate the model. Results From 1993 to 1999, 1,436 patients with stage IV or IIIB NSCLC with effusion were treated with platinum-based doublets (involving either paclitaxel, docetaxel, or gemcitabine). The response rate and median survival time were 20% and 8.2 months, respectively. One- and 2-year survivals were 33% and 11%, respectively. In multivariate analysis, six independent poor prognostic factors were identified: skin metastasis (hazard ratio [HR], 1.88), lower performance status (ECOG 1 or 2; HR, 1.46), loss of appetite (HR, 1.62), liver metastasis (HR, 1.32), ≥ four metastatic sites (HR, 1.20), and no prior surgery (HR, 1.16). A nomogram using six pretreatment prognostic factors was built to predict 1- and 2-year survival. Conclusion Six pretreatment factors can be used to predict survival in chemotherapy-naive NSCLC patients treated with standard chemotherapy. Using our prognostic nomogram, 1- and 2-year survival probability of NSCLC patients can be estimated before treatment. This prognostic model may help clinicians and patients in clinical decision making, as well as investigators in research planning.
Statistical Validation of the EORTC Prognostic Model for Malignant Pleural Mesothelioma Based on Three Consecutive Phase II Trials
Authors: Fennell Dean A. , Parmar Amit , Shamash Jonathan , Evans Marie T. , Sheaff Michael T. , Sylvester Richard , Dhaliwal Kevin , Gower Nicole , Steele Jeremy , Rudd Robin 
Published: December 2004

Purpose Malignant pleural mesothelioma (MPM) carries a poor prognosis due to chemoresistance. The European Organisation for Research and Treatment of Cancer (EORTC) prognostic model was reported to predict survival in MPM. Our retrospective analysis set out to test the validity of the model as a prognostic tool in patients treated in three phase II trials at St Bartholomew’s Hospital (London, United Kingdom) between 1999 and 2003. Patients and Methods A total of 145 patients were treated in three phase II trials; vinorelbine (VIN; 70 patients), vinorelbine/oxaliplatin (VO; 26 patients), and irinotecan/cisplatin/mitomycin C (IPM; 49 patients). Two subgroups, high-risk and low-risk, were defined by EORTC prognostic score (EPS). EPS was determined by a five-parameter model incorporating age, sex, histology, probability of diagnosis, and leukocyte count. An EPS cutoff of less than 1.27 (low risk) or more than 1.27 (high risk) was used to stratify Kaplan-Meier survival curves. Each of the EPS variables exhibited either trends or significant stratification of overall survival (OS). Results Multivariate analysis confirmed leukocyte count, Eastern Cooperative Oncology Group performance status, and sarcomatous histology as independent prognostic variables. EPS stratified OS in both individual and pooled trial datasets. No association between objective tumor response and EPS classification was identified by multinomial logistic regression. EPS stratified progression-free survival for the VO and IPM cohorts, but not for VIN. Conclusion This study validates the EPS system as a robust tool for stratifying small trials into low- and high-risk subgroups. EPS should facilitate patient selection and analysis in randomized clinical trials.
Oxytetracycline Residues in Four Species of Fish after 10-Day Oral Dosing in Feed
Authors: Chen C. Y. , Getchell R. G. , Wooster G. A. , Craigmill A. L. , Bowser P. R. 
Published: December 2004

Abstract
Residues of oxytetracycline (OTC) in serum, liver, and muscle–skin were measured in sunshine bass (female white bass Morone chrysops × male striped bass M. saxatilis), Nile tilapia Oreochromis niloticus, summer flounder Paralichthys dentatus, and walleyes Sander vitreus (formerly Stizostedion vitreum). These studies were conducted to compare the time for OTC concentrations to fall below 2.0 μg/g (the current tolerance set by the U.S. Food and Drug Administration (USFDA)) among fish species representing various culture conditions of freshwater and salt water as well as different temperature niches. The sum of mean tissue OTC concentration plus two standard deviations in the edible portion (muscle plus skin) of all fish was below 2.0 μg/g at 11 d postdosing. When possible, depletion data were fitted to a one-compartment pharmacokinetic model. Although temperature niche did not appear to consistently affect residue depletion within species, the warmwater species (sunshine bass and Nile tilapia) often had lower residue concentrations at each time point than did the coolwater species (summer flounder and walleye). For all test species, the period of OTC residue depletion below the USFDA tolerance level was less than the currently established 21-d withdrawal period for OTC in trout Salmo spp., salmon Oncorhynchus spp., and channel catfish Ictalurus punctatus.
Mischsubstratfermentation – ein energetisch begründetes Konzept
Authors: Babel W. 
Published: December 2004

AbstractOn the basis of the combustion enthalpy of microbial biomasses carbon substrates for the aerobically heterotrophic growth of microorganisms can be divided into substrates with energy excess (e.g. ethanol, n‐alkanes) and with energy deficit (or carbon excess, e.g. acetate, glucose). By combining substrates having different carbon energy ratios from both groups in a certain mixing proportion an improvement of the yield coefficients linked to a reduction of the specific heat production (kJ/g dry weight), an increase of the growth rate (h−1) and the velocity of the substrate utilization ought to be possible on condition that the co‐ or auxiliary‐substrate does not cause inhibition or (catabolite‐) repression effects.There are some examples corroborating the theoretical concept, e.g. the combinations ethanol/sucrose‐Candida utilis, methanol/xylose‐Hansenula polymorpha. In each case the specific growth rate and the yield coefficient on the mixture were higher than on any single substrate of the combination.Thermochemical methods are suitable for the optimizing the substrate mixing proportion.
Paraffinübergang aus der Kohlenwasserstoffphase zur Hefezelle
Authors: Stichel E. , Glombitza F. , Iske U. 
Published: December 2004

AbstractThe capability of the yeast Lodderomyces elongisporus to utilize solved paraffins in fermentation brothes could be demonstrated. The growth rate of this microorganism in the case of utilization of solved paraffins is higher as the most known dates.The saturated concentrations of solved hydrocarbons in the fermentation brothes are higher as in real solvent systems.The part of the solved hydrocarbon is a function of the power input, the diameter of oil drops, the fermentation conditions and the length of the paraffin chain.The organism growth rate depends on the solved paraffin concentration in the fermentation broth. This fact is one of the reasons for the variability of the consumption coefficients by utilization of paraffins with different chain lenghts.The results confirm the assumption that the transport of the paraffins from the oil drops to the cells takes place over water soluble phase.