bluuebunny/crossref_metadata_2025_split huggingface dataset:
Municipal firefighter exposure groups, time spent at fires and use of self‐contained‐breathing‐apparatus
Authors: Austin C.C. , Dussault G. , Ecobichon D.J. 
Published: August 2002

AbstractBackgroundPrevious studies have found significant associations between firefighting and cancer.MethodsFires, vehicle movement, and firefighter job assignment were determined, and storage and distribution of self‐contained‐breathing‐apparatus (SCBAs) were tracked for 12 months. Time spent at fires and use of SCBAs were calculated.ResultsOnly 66% of fire department personnel were 1st‐line combat firefighters. Number of runs was an unreliable surrogate for time spent at fires. Eight firefighter exposure groups were identified (based on job title, firehall assignment, and time spent at fires), ranging from no exposures to 3,244 min/year/firefighter. SCBAs appear to have been used for approximately 50% of the time at structural fires but for only 6% of the time at all fires.ConclusionsFailure of previous studies to identify homogeneous exposure groups may have resulted in misclassification and underestimates of health risks. The approach used in this study may be used in epidemiological studies to identify exposure/response relationships. Am. J. Ind. Med. 40:683–692, 2001. © 2001 Wiley‐Liss, Inc
Significance of a prenatally diagnosed del(10)(q23)
Authors: Zaslav A.L. , Fox J.E. , Jacob J. , Kazi R. , Allan S. , Shklooskaya T. , Sohal D. , Kleyman S.M. , Verma R.S. 
Published: August 2002

AbstractStructural chromosome mosaicism is rare. We report a case of prenatal mosaicism for a deletion of chromosome 10(q23). To our knowledge, there are only three reports of prenatally diagnosed cases of del(10)(q23). Two of these cases were due to an inherited fragile site. In the present case amniocentesis revealed 46,XY,del(10)(q23)[9]/46,XY[45]. Follow‐up chromosome analysis of peripheral blood and placental tissue from a phenotypically normal liveborn male revealed the del(10)(q23) in only 3/100 blood cells grown in low‐folate medium. It appears that prenatally diagnosed deleted (10q) mosaicism represents culture artifact and is not clinically significant. © 2002 Wiley‐Liss, Inc.
Clinical variability in mucolipidosis III (pseudo‐Hurler polydystrophy)
Authors: Tylki‐Szymańska Anna , Czartoryska Barbara , Groener Johanna E.M. , Ługowska Agnieszka 
Published: August 2002

AbstractMucolipidosis III (MLIII) is caused by a deficiency of UDP‐N‐acetylglucosamine:lysosomal enzyme N‐acetylglucosamine 1‐phosphotransferase (phosphotransferase) activity, an enzyme responsible for the formation of the recognition marker on most lysosomal enzymes. The consequences of this defect are impairment of many lysosomal catabolic processes. A deficiency of phosphotransferase activity causes two phenotypically different diseases: mucolipidosis II and a rare form, mucolipidosis III (pseudo‐Hurler polydystrophy). The purpose of this article is to report three patients with ML III, presenting quite different clinical courses: Patient 1 is a 13‐year‐old girl in whom the only symptoms of ML III were joint stiffness of the hands. Patients 2 and 3 are sibs: a 5‐year‐old boy with a severe form of ML III and his 2‐year‐old sister, who is less affected than her brother at the same age. A comparison of biochemical results and the clinical picture of our patients with cases in the literature is presented. © 2002 Wiley‐Liss, Inc.
Synthesis of a star‐shaped poly(ethylene‐co‐propylene) copolymer as a viscosity index improver for lubricants
Authors: Liou I‐Chun , Tsiang Raymond Chien‐Chao , Wu James , Liou Jin‐Shang , Sheu Hun‐Chang 
Published: August 2002

AbstractA saturated star‐shaped poly(ethylene‐co‐propylene) copolymer, (EP)star, has been synthesized for use as a viscosity index improver in lubricants. Polyisoprene arms were first anionically synthesized using n‐butyllithium as the initiator, followed by a linking reaction with divinylbenzene at the optimum temperature of 60°C. The resulting star‐shaped polyisoprene, (I)star, was then hydrogenated to eliminate the double bonds of the polyisoprene forming the poly(ethylene‐co‐propylene) structure. The degree of branching (number of arms on each molecule) increases with increase in the mole ratio of divinylbenzene to n‐butyllithium. Increasing the arm length adversely affects the linking efficiency and a minimum amount of tetrahydrofuran (THF) at a THF:n‐butyllithium molar ratio of 1.12 was needed in order to achieve a maximum linking efficiency of approximately 85%. The Tg of poly(ethylene‐co‐propylene) is about 10°C higher than that of the original polyisoprene. Compared with (I)star, (EP)star has a thermal decomposition temperature that is 50°C higher but is independent of the arm length or the degree of branching. Viscosity measurement results for (EP)star reveal that intrinsic viscosity depends only on the arm length but not the degree of branching. Adding 1 wt % of (EP)star markedly increases the viscosity index of a LN base oil. The addition of 1 wt % of (EP)star increases the viscosity index (95 for base oil) up to a number between 111 and 145, with the exact number depending upon its arm length and degree of branching. With a fixed arm length, an (EP)star having a higher degree of branching increases the viscosity index more than one having a lower degree of branching. On the other hand, the viscosity index increases with increase in the arm length when the degree of branching is fixed. Adding 1 wt % of (EP)star also causes a change in the pour point of the lubricant with the pour point decreasing with increase in the degree of branching. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 1911–1918, 2002
Different parameters controlling the initial solubility of two thermoplastics in epoxy reactive solvents
Authors: Bonnaud L. , Bonnet A. , Pascault J. P. , Sautereau H. , Riccardi C. C. 
Published: August 2002

AbstractThe influence of different factors on the miscibility of diglycidyl ether of bisphenol A (DGEBA)/thermoplastic blends was studied. DGEBA/poly(ether imide) (PEI) blends exhibited upper critical solution temperature behavior. The addition of a trifunctional epoxy [triglycidyl para‐amino phenol (TGpAP)] increased the miscibility window. The addition of diamines as hardeners could also increase [4,4′‐methylene‐bis(3‐chloro‐2,6‐diethylaniline) (MCDEA)] or decrease (4,4′‐diaminodiphenylsulfone) the miscibility window. DGEBA/poly(ether sulfone) (PES) blends showed lower critical solution temperature behavior. The addition of TGpAP had an effect similar to that for PEI blends, but the presence of MCDEA as a hardener decreased the miscibility of epoxy/PES blends. The modeling of the cloud‐point curves was performed with the Flory–Huggins equation (Flory, P. J. Principles of Polymer Chemistry; Cornell University Press: Ithaca, NY, 1953; p 672) according to the procedure developed by K. Kamide, S. Matsuada, and H. Shirataki (Eur Polym J 1990, 26, 379), with the interaction parameter used as the fitting parameter. A phenomenological model that takes into account the molar mass of DGEBA and the amount of TGpAP is proposed and is found to predict the cloud‐point temperature of any TGpAP/DGEBA/PEI blend. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 1385–1396, 2002
Mechanical and dynamic mechanical properties of rice husk ash–filled natural rubber compounds
Authors: Da Costa H. M. , Visconte L. L. Y. , Nunes R. C. R. , Furtado C. R. G. 
Published: August 2002

AbstractA laboratory‐sized two‐roll mill was used to incorporate rice husk ash into natural rubber (NR). A conventional vulcanization system was used for curing and cure studies were carried out on a Monsanto rheometer. Physical testing of the NR vulcanizates involved determining tensile and tear resistances and hardness. Swelling behavior of NR compounds and scanning electron microscopy were used to investigate the interaction between rice husk ash and natural rubber. Also, dynamical mechanical thermal analysis was used to assess filler–rubber interactions in terms of storage modulus (E′) and loss tangent (tan δ). For comparison purposes, two commercial fillers, precipitated silica (Zeosil‐175) and carbon black (N774), were also used. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 2331–2346, 2002
Novel dibutyltin oxide‐tributyl phosphate condensate as accelerator for the curing of the epoxy resin/4,4′‐diamino diphenyl sulfone system. II. Toughening of the resin with hydroxyl‐terminated poly(tetramethylene) glycols
Authors: Wu Qi , Xu Jianjun , Yu Yunzhao 
Published: August 2002

AbstractWhen a crystalline Bu2SnO‐Bu3PO4 condensate was used as a catalyst for the curing of the Epon 828/DDS system, the addition of hydroxyl group to epoxy group took place. On the basis of this reaction, direct employment of poly(tetramethylene) glycols (PTMG) as toughener for the epoxy resin system was successful. Morphology of the modified resin depended on the molecular weight and the concentration of PTMG. With the incorporation of a small amount of PTMG, the critical fracture energy of the cured resin was improved greatly, while the flexural strength and the modulus were less influenced. A slight enhancement in glass transition temperature (Tg) of the modified resin was found up to the PTMG concentration of 5 phr; further increase of the PTMG concentration caused a significant lowering of Tg. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 1237–1242, 2001
Effect of polymer compositions on the fabrication of poly(ortho‐ester) microspheres for controlled release of protein
Authors: Bai Xin‐Lai , Yang Yi‐Yan , Chung Tai‐Shung , Ng Steve , Heller Jorge 
Published: August 2002

AbstractEight kinds of self‐catalyzed poly(ortho‐esters) (POEs) are used to fabricate bovine serum albumin (BSA)‐containing microspheres using a W/O/W double‐emulsion solvent extraction/evaporation method. All eight kinds of POE polymers used in this study are shown able to form microspheres under proposed fabrication conditions. The surface morphology and inner structure of the microspheres are analyzed using scanning electron microscopy (SEM). The microspheres have a size range from 64.7 to 120.2 μm. POE with a higher viscosity leads to bigger microspheres. It was found that the POE composition has a significant effect on BSA release profiles. POEs, which are more hydrophilic and contain a greater amount of glycolide or lactate (latent acid), yield higher BSA release rates. Specifically, POE containing 1,6‐hexanediol diglycolide (HD‐diGL) microspheres have the highest BSA release rate after a 20‐day test through a combination of surface erosion and diffusion mechanisms. POE containing a high percentage of the trans‐cyclohexanedimethanol (CDM) segment tends to yield microspheres with a lower release rate because of its hydrophobic nature. It was also found that the BSA release rate is more rapid at 37°C than at 22°C because of faster polymer degradation and water penetration at 37°C. Experimental results suggest that various protein release rates can be achieved by using different compositions of POEs. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 1630–1642, 2001
Characterization of structure of comblike polymer by pyrolysis gas chromatography and Fourier transform infrared spectroscopy
Authors: Yang Rui , Li Guoping , Wang Kunhua 
Published: August 2002

AbstractThe characterization of branching in comblike polymers using high‐resolution pyrolysis gas chromatography (HRPGC) and Fourier transform infrared spectroscopy (FTIR) is investigated. The branching type can be identified from characteristic peaks of monomer and a group of dimers in pyrograms derived from α‐ and β‐scission of branched atoms. By resolving the overlapping bands between 2800–3000 cm−1, the relative absorbance of CH2 can be used to calculate the average branch length L. This method is helpful in evaluating the property of drag‐reduction agents. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 359–363, 2001
Creep enhanced adsorbtion of water or aqueous zinc chloride solution increases the creep rate of nylon 6,6
Authors: Nair S. V. , Donovan J. A. 
Published: August 2002

AbstractThe creep behavior of nylon 6,6 at 21°C was significantly altered when the local “dry” environment was changed to water mist or an aqueous zinc chloride mist. Nylon 6,6 was found to exhibit logarithmic creep because the relation between the log of the strain rate and the creep strain was linear with a negative slope. The effect of changing the creep environment from dry to wet, with the addition of moisture from an ultrasonic humidifier was to decrease the negative slope by 50–70% within 5–10 min. This effect could be interpreted as a decrease in modulus, which allowed for easier creep deformation. Based on the stress‐free diffusivity of water in nylon and the dimensions of the test sample the time to saturate the sample was estimated to be about 100 h. Therefore, there appeared to be synergism between the creep deformation and the environment that dramatically enhanced the rate of saturation and slowed the decrease in the creep rate. The tentative explanation provided is that the aqueous solutions, by binding to the hydrogen bonds in nylon, are dragged into the sample during creep deformation, and the dragged‐in aqueous solution then plasticizes nylon. This is analogous to the conclusion in another recent study that showed that deformation, during a hardness test, in the presence of aqueous zinc chloride, transported the solution species deeper into the sample than could be reasonably explained by ordinary diffusion processes. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 494–497, 2001
Modeling of particle growth and morphology in the gas phase polymerization of butadiene. I. Model and its solution method
Authors: Zhao Junzi , Sun Jianzhong , Zhou Qiyun , Pan Zuren 
Published: August 2002

AbstractAn improved multigrain model designed to simulate the polymeric particle growth and morphology in the gas phase polymerization of butadiene was developed. In the model, the effects of intraparticle heat and mass transfers, heat and mass transfer resistances at the particle boundary layer, sorption of 1,3‐butadiene in 1,4‐cis‐polybutadiene, and intrinsic kinetics on the polymeric particle growth and morphology were considered. An improved numerical method was also proposed. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 719–729, 2001
Three‐site mechanism and molecular weight: Time dependency in liquid propylene batch polymerization using a MgCl2‐supported Ziegler‐Natta catalyst
Authors: Shimizu Fumihiko , Pater Jochem T. M. , Weickert Günter 
Published: August 2002

AbstractThis article demonstrates that the molecular weight of propylene homopolymer decreases with time, and that the molecular weight distribution (MWD) narrows when a highly active MgCl2‐supported catalyst is used in a liquid pool polymerization at constant H2 concentration and temperature. To track the change in molecular weight and its distribution during polymerization, small portions of homo polymer samples were taken during the reaction. These samples were analyzed by Cross Fractionation Chromatograph (CFC), and the resulting data were treated with a three‐site model. These analyses clearly showed that the high molecular weight fraction of the distribution decreases as a function of time. At the same time, the MWD narrows because the weight‐average molecular weight decreases faster than the number‐average molecular weight. A probable mechanism based on the reaction of an external donor with AlEt3 is proposed to explain these phenomena. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 1035–1047, 2001
Silane‐modified PVC pervaporation membranes for bromoform/water separation
Authors: Sluszny Ariel , Silverstein Michael S. , Narkis Nava , Narkis Moshe 
Published: August 2002

AbstractThe transport properties of a unique family of silane‐modified poly(vinyl chloride) (PVC) pervaporation membranes for the separation of halogenated hydrocarbons from water were investigated. The PVC was modified by using a vinyl silane to improve its resistance to attack by halogenated hydrocarbons and to increase the flux. Two preparation routes were used: Route i included an initiator to promote the vinyl reaction before the hydrolysis and condensation of the methoxy silane group, whereas Route ni did not. The structures of the membranes were characterized and related to the transport properties, as derived from batch pervaporation experiments. The permeability of unmodified PVC membranes increases with exposure to haloorganics at low concentrations. Initially, the modified membranes exhibited a higher permeability than PVC and a lower selectivity. At long pervaporation times, the silane‐modified membranes exhibited a higher selectivity than PVC. The different preparation routes led to different morphologies, which affected the performance of the membranes; Route ni membranes exhibited higher permeabilities and selectivity than Route i membranes. Rubbery polydimethylsiloxane membranes were resistant to haloorganics but their high water permeability and low selectivity make them unsuitable for this pervaporative separation. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 1429–1438, 2001
Influence of cure treatment on extent of reaction and glassy modulus for BADGE‐DDM epoxy resin
Authors: Ellis B. , Found M. S. , Bell J. R. 
Published: August 2002

AbstractThe extent of conversion of epoxy groups cured with diaminodiphenyl methane, a diamine, at 100°C was approximately 100%, and the glass‐transition temperature (T) was found to be an increasing function of cure time with very large increases with extended postcure treatments at 180°C. However, this considerable increase in the Tg with postcure at 180°C was not due to the reactions of epoxy and amine groups. The specific volume reduced with the Tg to a minimum at 103° for the cured samples but showed a very slight increase with the Tg for the postcured samples. It was also found that the glassy modulus (Eg) was a linear decreasing function of the Tg. There were two separate relationships between the Eg and the rubbery modulus that depended on the cure conditions and suggested that the “structure” formed due to cure at a temperature of 100°C was different than that at postcure, which was 180°C. The most sensitive structural parameter for these cured epoxy resins was their T. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 1265–1276, 2001
Immobilization of lipase on poly(N‐vinyl‐2‐pyrrolidone‐co‐styrene) hydrogel
Authors: Basri M. , Harun A. , Ahmad M. B. , Razak C. N. A. , Salleh A. B. 
Published: August 2002

AbstractLipase from Candida rugosa was immobilized by entrapment while polymerizing a poly(N‐vinyl‐2‐pyrrolidone‐co‐styrene) [poly(VP‐co‐ST)] hydrogel using ethylene dimethacrylate (EDMA) as the crosslinking agent. The immobilized enzymes were used in the esterification reaction of oleic acid and butanol in hexane. The activities of the immobilized enzymes and the leaching ability of the enzyme from the support with respect to the different compositions of the hydrogels were investigated. The thermal, solvent, and storage stability of the immobilized lipases were also determined. The activities were relatively higher when the percent compositions of VP(%):ST(%) were 50:50 and 30:70. The lipase immobilized on VP(%):ST(%) 50:50 showed the highest thermal stability, while lipase immobilized on VP(%):ST(%) 30:70 exhibited the highest solvent stability. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 1404–1409, 2001
Three‐group type mechanism in the curing behavior of polyacrylate and blocked toluene diisocyanate
Authors: Xiao Dequan , Chen Deben , Zhou Zonghua , Zhong Anyong 
Published: August 2002

AbstractAbstract:The curing behavior of two resins, five blocked toluene diisocyanate (TDI) crosslinkers and polyacrylate, was studied using Torsional Braid Analysis (TBA) to examine their dynamic mechanical properties. The curing process was clearly divided into two stages. Associated with data from in situ FTIR at the molecular level, the first stage was the reaction of deblocked NCO and hydroxyl in polyacrylate. In the second stage, the deblocked NCO attacked the hydrogen in NH group of the urethane bond to conduct deep curing. Computer modeling was used to investigate the lowest‐energy configuration of the crosslinker molecule. The space hindrance effect in the molecule causes this type of three‐group crosslinking curing mechanism in the blocked TDI crosslinker. © 2002 John Wiley & Sons, Inc. J Appl Polym Sci 83: 112–120, 2002
Physical properties of twisted structures. II. Industrial yarns, cords, and ropes
Authors: Pan Ning , Brookstein David 
Published: August 2002

AbstractIn this article, we review the progress made in the area of industrial twisted fibrous structures. First, we focus on the general geometrical description of the structures, and then move to issues including the tensile behavior and fracture process. The effects of fiber bending and torsion, strain rate, and viscoelasticity are also discussed. The influences of both dynamic and fatigue loadings are studied as well. Discussion on the fiber blending and on the behavior of blended hybrid structures is provided. Further, a special section is included in which six specific topical areas, their significance toward textile science, and the progress made in these areas are introduced and summarized. Finally, experimental issues are discussed. Although this article is intended to serve as a complete review of the subject, because of the limit of both time and space, we can only focus on the areas in which we are most familiar. This article, therefore, is by no means exhaustive or authoritative in every topic discussed. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 610–630, 2002
Super‐osteons (remodeling clusters) in the cortex of the femoral shaft: Influence of age and gender
Authors: Bell Karen L. , Loveridge Nigel , Reeve Jonathan , Thomas Christopher D.L. , Feik Sophie A. , Clement John G. 
Published: August 2002

AbstractPrevious studies of cortical remodeling in the fractured femoral neck indicated that the merging of spatially clustered remodeling osteons could result in the formation of deleteriously large cavities associated with femoral neck fracture. This study aimed to identify whether remodeling osteons in the femoral shaft were also clustered and to assess the influence of age and gender. Microradiographic images of femoral mid‐shaft cross‐sections from 66 subjects over 21 years of age were analyzed to determine the number, size and location of all Haversian canals. Those most recently remodeled were identified using an edge‐detection algorithm highlighting the most marked differential gradients in grey levels. Cluster analysis (JMP software) of these osteons identified the proportion of recently remodeled osteons that were within 0.75mm clusters. As in the femoral neck, remodeling osteons were significantly more clustered than could occur by chance (real, 59.4%; random, 39.4%; P < 0.0001). The density of these clusters (number/mm2) was not significantly associated with subject age or gender but was greatest near the periosteum and decreased toward the marrow cavity (periosteal 0.043 ± 0.004; mid‐cortex 0.028 ± 0.003; endosteal 0.017 ± 0.002). Cortical porosity increased with age. The presence of giant canals (diameter >385μm) was inversely related to the presence of clusters (R2 = 0.237, P < 0.0001). This data suggest that remodeling osteons tend to be spatially colocalized in the shaft as they are in the neck of the femur and their presence is independent of age or gender. We propose that these remodeling clusters be termed super‐osteons. The negative relationship between super‐osteons and giant canals raises the intriguing possibility that loss of the control of remodeling depth results in the merging of osteonal systems to form deleteriously large cortical cavities with a marked reduction in bone strength. Anat Rec 264:378–386, 2001. © 2001 Wiley‐Liss, Inc.