bluuebunny/crossref_metadata_2025_split huggingface dataset:
Plasma‐polymerized films of trimethylsilane deposited on cold‐rolled steel substrates. Part 1. Characterization by XPS, AES and TOF‐SIMS
Authors: Sabata A. , van Ooij W. J. , Yasuda H. K. 
Published: December 2004

AbstractPlasma‐polymerized coatings on metal substrates have been suggested as corrosion protection layers, but not much is known about the properties of these films and how these properties relate to the corrosion performance of coated metals. In this study, trimethylsilane plasma films were deposited on cold‐rolled steel (CRS) under different deposition conditions. Angular‐dependent XPS, AES and time‐of‐flight (TOF)‐SIMS were used to characterize the films. These three techniques were highly complementary in nature. All films were silicon‐based and the hydrocarbon content was a function of the deposition conditions. The AES depth profiles indicated that pretreatment of the substrate with oxygen had a significant effect on the type of film produced. Both TOF‐SIMS and XPS revealed that the surface of the film was different from the bulk. The surface was oxygen‐rich and was apparently modified upon exposure of the plasma film to the atmosphere. Both silicon and carbon were highly oxidized in the surface layers. Thus, these plasma films consist of at least three distinctly different regions: an interfacial region where the film is intimately mixed with the metal oxide; a bulk region with approximately the same elemental composition as the monomer; and a highly oxidized surface region. A correlation between the type of plasma film produced and the deposition conditions is discussed briefly.
Application of transmission Mössbauer spectroscopy to the surface study of Ni(II)–Fe(III) hydroxide electrocatalysts: Comparison with AES data
Authors: Kamnev Alexander A. , Angelov Venelin , Smekhnov Alexander A. 
Published: December 2004

AbstractTransmission Móssbauer spectra of binary coprecipitated nickel(II)–iron(III) hydroxides (molar ratios 9:1 and 4:1) are analysed and compared with the results of AES analyses of their surface composition. A correlation between the data of the above techniques has been noted, indicating a redistribution of the components (i.e. Ni and Fe) in the surface layers, the latter being enriched with iron(III) as compared to the bulk. The results obtained are in good agreement with an excellent electrocatalytic activity of composite Ni–Fe hydroxide systems towards anodic oxygen evolution in alkaline electrolytes, taking into account a distinctly exhibited ‘surface’ electrocatalytic effect of ferric species on the nickel hydroxide electrode in the anodic oxygen evolution process revealed previously. Transmission Móssbauer spectroscopy has been shown to be a highly effective probe sensitive both to various bulk and surface effects related to the solid phases studied.
Segregation of phosphorus at the metal/scale interface during oxidation of Ni and Ni–20Cr
Authors: Kurbatov G. , Viefhaus H. , Grabke H. J. 
Published: December 2004

AbstractThe segregation of phosphorus at the metal/scale interface formed upon oxidation of Ni and Ni–20Cr at high temperatures was studied. Auger electron spectroscopy with high spatial resolution was used in combination with thermogravimetric measurements. The chemistry of the interface was related to its microstructure. The effects of oxidation procedure and surface preparation on the composition and microstructure of the interface were considered.The incorporation of phosphorus in an oxidized state into the NiO scale formed at 700°C and 1000°C was revealed. The oxidation rate at 1000°C is retarded by segregated phosphorus.The segregation of phosphorus at the metal/scale interface formed upon oxidation of Ni–20Cr alloy at high temperatures was observed for oxidation at low and at atmospheric oxygen pressures. Phosphorus and sulphur segregated at the interface retard the oxidation rate at the initial stage of oxidation at 1000°C and at atmospheric oxygen pressures.
Composite interface analysis using voltage contrast XPS
Authors: Miller James D. , Harris William C. , Zajac Gerry W. 
Published: December 2004

AbstractVoltage contrast x‐ray photoelectron spectroscopy (XPS) was developed to characterize the interfacial bonding properties in carbon fiber‐reinforced polymer matrix composites. The differing electrical properties of the fiber and matrix allow biasing of the matrix and separation of the fiber and matrix signals in the XPS spectrum. The result is a quantitative measure of the relative amount of exposed fiber and exposed matrix at the fracture surface of a failed composite specimen. A parameter used to describe the interfacial bonding is defined as the ratio of the areas of the carbon 1s peaks from the fiber and matrix components and is referred to as the interfacial bonding ratio or Cf/Cm. Typical values of Cf/Cm for polyacrylonitrile‐based carbon fiber‐reinforced polymer matrix composites range from zero (excellent bonding) to three (poor bonding). The voltage contrast technique was used to demonstrate the effects of matrix resin chemistry, electrolytic oxidative fiber surface treatment, fiber processing temperature, fiber modulus and hydrothermal damage on interfacial bonding.
Spectroscopic studies of surface copper spinels. Influence of pretreatments on chemical state of copper
Authors: Sepúlveda A. , Márquez C. , Rodríguez‐Ramos I. , Guerrero‐Ruíz A. , Fierro J. L. G. 
Published: December 2004

AbstractThe nature of copper species of a series of alumina‐supported copper samples was investigated by the kinetics of reduction, x‐ray photoelectron spectroscopy, temperature‐programmed desorption‐mass spectrometry of chemisorbed NO and infrared spectroscopy of chemisorbed NO and CO probes. The role of these copper species was also examined in the catalytic decomposition of NO. The surface properties of copper were found to depend strongly on both Cu loading and calcination treatment. At Cu contents as low as 0.6 wt.%, Cu2+ ions from a well‐dispersed interacting phase at the alumina surface, which upon calcination forms a surface spinel CuAl2O4. At copper contents up to 3.2 wt.%, both the surface spinel CuAl2O4 and a segregated CuO phase were clearly distinguished. The partial reduction of these species upon thermal treatment under high vacuum, the ability of the surface sites to chemisorb NO and CO probes and their implications in the catalytic decomposition of NO are discussed.
X‐ray photoelectron spectroscopy study of aluminium surfaces prepared by anodizing processes
Authors: Cordier F. , Ollivier E. 
Published: December 2004

AbstractX‐ray photoelectron spectroscopy was used to compare several pretreatments of aluminium surfaces used in aerospace and aircraft industry. These anodizing processes, which aim at preparing the metal surface for adhesive bonding or painting, all lead to the formation of an aluminium oxide layer. A set of aluminium samples representing the various steps of the processes was analysed by XPS. After curve fitting of the aluminium peak (Al 2p) and oxygen peak (O 1s) recorded at high energy resolution, and correction of charging effects, residual energy shifts between the spectra can be observed. This could be attributed to differences in the Fermi energy values between the treated aluminium surfaces. A classification based on this parameter of the relative Lewis acid–base character of these treated surfaces is proposed. The evolution of this parameter after exposure of the treated samples to a moist environment was also studied.
Processability of rigid poly(vinyl chloride) compounds I. Evaluation of extrusiometer data
Authors: Pukánszky Béla , Nagy Tibor T. , Kelen Tibor , Krall György , Tölgyesi‐Papp Emöke 
Published: December 2004

AbstractThe results of the extrusiometer measurements made on a great number of different rigid poly(vinyl chloride) (PVC) compositions are analyzed. The laboratory extruders used in the experiments can be considered to be isothermic. The output rate is proportional to the extrusion speed and almost independent of the composition. The other characteristics—torque, die and back pressure—significantly depend on the composition of the compounds. The back pressure proved to be proportional to the die pressure, and thus does not give additional information. Processability is well characterized by the dissipated energy which can be calculated from the difference of the total introduced mechanical energy and the energy required to transport the melt through the capillary. The dissipated energy is closely related to the fusion characteristics of the compounds.
Polycaprolactone as a permanent plasticizer for poly(vinyl chloride)
Authors: Deanin Rudolph D. , Zheng‐Bai Zhang 
Published: December 2004

AbstractPolycaprolactone at moderate usage levels has been determined to provide desirable modifications of both rigid and plasticized poly(vinyl chloride). In rigid PVC it effected significant improvement in melt processing as well as good modulus, tensile strength, and kerosene resistance. Impact strength was not measurably altered, but heat‐distortion temperature was appreciably lowered. In flexible PVC, polycaprolactone contributed increased tensile strength and ultimate elongation, reduced volatility, and kerosene extraction. Lowering of modulus and flex temperatures were similar to conventional liquid polymeric plasticizers, but melt processability was not as good as lower‐molecular‐weight plasticizers.
Reinforced poly(vinyl chloride)—the ultimate rigid vinyl
Authors: Deanin Rudolph D. , Michaels George C. 
Published: December 2004

AbstractRigid poly(vinyl chloride) was reinforced with 10 to 40 phr of 1/4‐inch glass fiber. This improved flexural modulus up to 140 percent, flexural strength 40 percent, and heat‐deflection temperature 8°C; and reduced creep by 90–95 percent, and the coefficient of thermal expansion by 50 percent. Thus a typical Type I rigid vinyl with glass reinforcement had flexural modulus 1,164,000 psi, flexural strength 16,500 psi, notched Izod impact strength 5.1 fpi; creep only 12 percent of normal unreinforced material, coefficient of thermal expansion only 50 percent of normal unreinforced material, and heat‐deflection temperature 79°C. Such balance of properties elevates rigid vinyl from a commodity plastic up to an engineering thermoplastic, capable of much wider and more economical utilization in high‐performance applications.
Monomeric plasticizers for PVC medical devices: Safety and regulatory status
Authors: Group Edward F. 
Published: December 2004

AbstractAs the data base for phthalates and other monomeric plasticizer classes is broadened, and our understanding of toxic mechanisms and potential risks improves, it is anticipated that industry and government agencies alike will demonstrate that these products can be safely used. Progress will depend heavily on advancements in predictive animal testing science, and extrapolation of animal data to meaningful risk assessment in humans.Future directions for testing initiatives are being determined, with a leadership role being played by CMA. Much exploratory work remains, but the focus will continue to narrow on areas critical to human risk assessment.
Morphology of mass PVC
Authors: Fischer Nicolas 
Published: December 2004

AbstractThe evolution of the morphology of the PVC grains during the mass polymerization of vinylchloride monomer (VCM) has been studied. After nucleation of primary particles, a rapid flocculation step occurs that leads to grains. Continued polymerization inside the grains results in a progressive reduction in the pore volumes. Continuing the reaction to completion, if appropriate by adding a further amount of monomer, causes densifying of the grains leading, in some cases, to vitreous grains, which therefore are related to the cleanliness of the reactors used. The changes in the size of the constituent compartment affect both the process of preparation and the processing of the final product: degassing rate of monomer, and plasticizing rate. Thus, control of the degrees of conversion, associated with perfect cleaning of the reactor, which is easy in the case of the new vertical reactors, constitutes the key factors in the reproducibility of the process and the quality of the PVC produced.
Predictors of 6‐minute walk test results in lean, obese and morbidly obese women
Authors: Hulens M. , Vansant G. , Claessens A. L. , Lysens R. , Muls E. 
Published: December 2004

The aim of this study was first, to assess the presence of medical conditions that might interfere with walking; second, to assess the differences in walking capacity, perceived exertion and physical complaints between lean, obese and morbidly obese women; and third, to identify anthropometric, physical fitness and physical activity variables that contribute to the variability in the distance achieved during a 6‐minute walk test in lean and obese women.A total of 85 overweight and obese females (18–65 years, body mass index (BMI) ≥ 27.5 kg m−2), 133 morbidly obese females (BMI ≥ 35 kg m−2) and 82 age‐matched sedentary lean female volunteers (BMI ≤ 26 kg m−2) were recruited. Patients suffering from severe musculoskeletal and cardiopulmonary disease were excluded from the study. Prior to the test, conditions that might interfere with walking and hours of TV watching were asked for. Physical activity pattern was assessed using the Baecke questionnaire. Weight, height, body composition (bioelectrical impedance method), isokinetic concentric quadriceps strength (Cybex) and peak oxygen uptake (peakVO2—bicycle ergometer) were measured. A 6‐minute walk test was performed and heart rate, walking distance, Borg rating scale of perceived exertion (RPE) and physical complaints at the end of the test were recorded.In obese and particularly in morbidly obese women suffering from skin friction, urinary stress incontinence, varicose veins, foot static problems and pain, wearing insoles, suffering from knee pain, low back pain or hip arthritis were significantly more prevalent than in lean women (P < 0.05). Morbidly obese women (BMI > 35 kg m−2N = 133) walked significantly slower (5.4 km h−1) than obese (5.9 km h−1) and lean women (7.2 km h−1, P < 0.05), were more exerted (RPE 13.3, 12.8 and 12.4, respectively, P < 0.05) and complained more frequently of dyspnea (9.1%, 4.7% and 0% resp., P < 0.05) and musculoskeletal pain (34.9%, 17.7% and 11.4% resp., P < 0.05) at the end of the walk. In a multiple regression analysis, 75% of the variance in walking distance could be explained by BMI, peakVO2, quadriceps muscle strength age, and hours TV watching or sports participation.These data suggest that in contrast with lean women, walking ability of obese women is hampered not only by overweight, reduced aerobic capacity and a sedentary life style, but also by perceived discomfort and pain. Advice or programs aimed at increasing walking for exercise also need to address the conditions that interfere with walking, as well as perceived symptoms and walking difficulties in order to improve participation and compliance.
Estimating Percentiles of Uncertain Computer Code Outputs
Authors: Oakley Jeremy 
Published: December 2004

SummaryA deterministic computer model is to be used in a situation where there is uncertainty about the values of some or all of the input parameters. This uncertainty induces uncertainty in the output of the model. We consider the problem of estimating a specific percentile of the distribution of this uncertain output. We also suppose that the computer code is computationally expensive, so we can run the model only at a small number of distinct inputs. This means that we must consider our uncertainty about the computer code itself at all untested inputs. We model the output, as a function of its inputs, as a Gaussian process, and after a few initial runs of the code use a simulation approach to choose further suitable design points and to make inferences about the percentile of interest itself. An example is given involving a model that is used in sewer design.
Statistical Image Analysis for a Confocal Microscopy Two-Dimensional Section of Cartilage Growth
Authors: Al-Awadhi Fahimah , Jennison Christopher , Hurn Merrilee 
Published: December 2004

SummaryImages are the source of information in many areas of scientific enquiry. A common objective in these applications is the reconstruction of the true scene from a degraded image. When objects in the image can be described parametrically, reconstruction can proceed by fitting a high level image model. We consider the analysis of confocal fluorescence microscope images of cells in an area of cartilage growth. Biological questions that are posed by the experimenters concern the nature of the cells in the image and changes in their properties with time. Our model of the imaging process is based on a detailed analysis of the data. We treat the true scene as a realization of a marked point process, incorporating this as the high level prior model in a Bayesian analysis. Inference is by simulation using reversible jump versions of Markov chain Monte Carlo algorithms which can handle the varying dimension of the image description arising from an unknown number of cells, each with its own parameters.
Higher Hb level is associated with better early functional recovery after hip fracture repair
Authors: Lawrence Valerie A. , Silverstein Jeffrey H. , Cornell John E. , Pederson Thomas , Noveck Helaine , Carson Jeffrey L. 
Published: December 2004

BACKGROUND: The benefits and indications for blood transfusion are controversial. One possible reason to transfuse is to improve functional recovery after major surgery. However, the data linking improved function with higher Hb concentration are limited.STUDY DESIGN AND METHODS: A retrospective cohort study was performed in 5793 patients at least 60 years old undergoing hip fracture repair at 20 academic and community hospitals. The primary outcome was distance walked at the time of discharge from the hospital. The mean postoperative Hb concentration was the main exposure variable and was defined as the average value from Day 1 after surgery to discharge. We used robust regression to assess the association between postoperative Hb level with distance walked, controlling for other preoperative variables that could influence functional recovery.RESULTS: On bivariate analysis, the predicted distance walked at discharge in feet (95% CI) increased with higher Hb levels (7 g/dL, 56 feet [42‐70]; 8 g/dL, 61 feet [54‐68]; 9 g/dL, 67 feet [64‐70]; 10 g/dL, 74 feet [72‐77]; 11 g/dL, 83 feet [80‐85]; 12 g/dL, 92 feet [87‐96]). After adjustment for other factors associated with ability to walk, higher average postoperative Hb level was independently associated with walking greater distance (p < 0.001).CONCLUSIONS: Higher postoperative Hb level may improve functional recovery after hip fracture repair. If confirmed with clinical trials, this finding would provide a rationale to maintain higher Hb concentrations in elderly patients recovering from surgery.
Mutations in GYPB exon 5 drive the S–s–U+var phenotype in persons of African descent: implications for transfusion
Authors: Storry Jill R. , Reid Marion E. , Fetics Susan , Huang Cheng‐Han 
Published: December 2004

BACKGROUND: The S–s–U– phenotype in African Americans is due to a GYPB deletion, however the molecular basis for the S–s–U+var phenotype is poorly understood. Variable reactivity of S–s–U+var RBCs with monoclonal anti‐He or by anti‐U has been demonstrated, however the underlying molecular bases for this phenotype remain to be established.STUDY DESIGN AND METHODS: Hemagglutination was performed on 104 S–s– blood samples using monoclonal anti‐He and anti‐U. GYPB was sequenced from selected samples. Allele and exon‐specific PCR analysis was used to identify wild‐type and mutant alleles.RESULTS: The RBCs of 49‐percent S–s– samples were identified as S–s–U+var by hemagglutination. Sequencing analysis of 41 samples revealed 1) a point mutation at +5 (g > t) of intron 5 that resulted in skipping of exon 5 in 34 samples; 2) two mutations (208G > T and 230C > T) caused partial skipping of exon 5 in four samples due to activation of a cryptic 3′ splice site that resulted from a C > G transversion at nt251 present in all GYPB*S alleles and most GYPB*s alleles tested. Three samples were heterozygous for the mutated alleles.DISCUSSION: T he S–s–U+var phenotype arises from changes in or around GYPB exon 5. The weak expression of U and in most examples, He, may be due to low levels of normal transcription of the variant gene or to posttranscriptional down regulation.
Autoantibody formation after alloimmunization: are blood tranfusions a risk factor for autoimmune hemolytic anemia?
Authors: Young Pampee P. , Uzieblo Alison , Trulock Elbert , Lublin Doug M. , Goodnough Lawrence T. 
Published: December 2004

BACKGROUND:  The development of RBC autoanti‐bodies resulting from or associated with allogeneic blood transfusions (i.e., RBC autoimmunization) is not a well‐recognized complication of RBC transfusions.STUDY DESIGN AND METHODS:  T he presentation, laboratory evaluation, clinical course, and management of two patients whose autoimmune hemolytic anemia followed allogeneic blood transfusion and occurred in association with the development of one or more alloantibodies is described. A retrospective analysis was performed of our blood‐bank records over 1 year to determine the frequency of RBC autoimmunization associated with alloimmunization.RESULTS:  Out of 2618 patients who had a positive DAT or IAT, 121 were identified with RBC autoantibodies; 41 of these patients had both allo‐ and autoantibodies to RBC antigens, whereas the remainder, 80, had only autoantibodies. At least 34 percent (12/41) of these patients (none with hemoglobinopathy) developed their autoantibodies in temporal association with alloimmuni‐zation after recent blood transfusion(s).CONCLUSION:  RBC autoimmunization and the development of autoimmune hemolytic anemia should be recognized as a complication of allogeneic blood transfusion. The need for additional blood transfusion was successfully avoided in one patient by treatment with recombinant human EPO and corticosteroid therapy. Once RBC autoimmunization is identified, subsequent management should incorporate a strategy that minimizes subsequent exposure to allogeneic blood.