bluuebunny/crossref_metadata_2025 huggingface dataset:
Zinc in Extremely Low-birthweight or Very Preterm Infants
Authors: Giles Ed , Doyle Lex W.
Published: October 2007

With the increasing survival of extremely low-birthweight or very preterm infants, it is becoming increasingly important to understand micronutrient needs. Most fetal accretion of zinc occurs in the third trimester, when liver stores are laid down, putting these babies at risk of clinical deficiency. It remains difficult to monitor zinc concentrations without clear reference ranges, but some evidence can guide requirements to avoid deficiency. It is not clear whether matching fetal accretion is necessary or whether increasing zinc balance improves short- or long-term outcomes in preterm infants. Given the increasing knowledge, it is possible to make recommendations on the amount of zinc that should be provided, whether by the parenteral or enteral route, in human or formula milk to the smallest babies.
Brachial Plexus Injury in the Newborn
Authors: Sutcliffe Trenna L.
Published: October 2007

Brachial plexus palsy in the neonate is classified according to the anatomic location and type of injury. Upper plexus lesions are observed most frequently. The overall rate of perinatal brachial plexus palsy (PBPP) has remained stable for the last 3 decades, although risk factors for the injury are well described. The true rate of full recovery after PBPP remains controversial. Knowledge of an infant's PBPP classification can assist in predicting long-term outcome. A thorough physical examination is essential to make the diagnosis, evaluate for comorbidities, determine the treatment plan, and assess the need for referral. Additional investigations typically are not indicated. Initial management of the infant who has PBPP includes parent counseling, physical or occupational therapy, and clinical observation of the infant. A proportion of affected infants eventually requires surgical intervention or alternative therapeutic approaches, including botulinum toxin injections.
Fetal Magnetic Resonance Imaging
Authors: Barth Richard A. , Rubesova Erika
Published: October 2007

Fetal magnetic resonance imaging (MRI) is emerging as an important complementary clinical tool to ultrasonography for evaluation of fetal anomalies. Fetal MRI has been in clinical use since 1983; but, early magnetic resonance (MR) sequences were of several minutes’ duration, resulting in significant fetal motion artifact. The recent development of ultrafast MRI sequences allows subsecond image acquisition, minimizing the artifact related to fetal motion. Accurate diagnosis of a fetal anomaly by MRI has the potential to improve parental counseling regarding prognosis and treatment options, assist clinicians with fetal and postnatal management decisions, and plan delivery at an appropriate center for treating the diagnosed anomaly. This review discusses MRI safety and techniques; clinical indications for fetal MRI; and the MR appearance of normal anatomy and anomalies involving the fetal neck, chest, and abdomen.
The Genomics of Bronchopulmonary Dysplasia
Authors: Bhandari Vineet , Gruen Jeffrey R.
Published: October 2007

Bronchopulmonary dysplasia continues to be a major cause of neonatal morbidity, despite significant progress in the treatment of preterm neonates. The cause is multifactorial, with prematurity as the primary culprit and other factors including ventilator-induced lung injury, exposure to oxygen, and inflammation. Recent studies in twins show that 53% of the variance is attributable to genetic factors. In this review, we critically evaluate published association studies of candidate gene polymorphisms.
Efficacy and Safety of Erythropoiesis-Stimulating Proteins in Myelodysplastic Syndrome: A Systematic Review and Meta-Analysis
Authors: Ross Susan D. , Allen I. Elaine , Probst Corey A. , Sercus Brian , Crean Sheila M. , Ranganathan Gayatri
Published: October 2007

Learning Objectives

After completing this course, the reader will be able to: Provide the current best estimates of hemoglobin response with erythropoiesis-stimulating proteins in anemia of MDS.Specify prognostic factors for response that are potentially useful.Describe the gaps in the existing evidence base regarding these agents in MDS.

Access and take the CME test online and receive 1 AMA PRA Category 1 Credit™ at CME.TheOncologist.com
Covictims of Capital Murder: Statements of Victims’ Family Members and Friends Made at the Time of Execution
Authors: Vollum Scott , Longmire Dennis R.
Published: October 2007

The death penalty is often touted as a punishment providing the only way to truly serve justice and offer closure for covictims (defined as family members or friends of murder victims’). These rationales are rarely structured around the actual words of these individuals, however. The findings in this study suggest that such rhetoric oversimplifies and often misrepresents the experiences and perspectives of covictims. Through their own words, we learn that the death penalty is not always the soothing salve for the pain and suffering of covictims we wish it to be. Rather, we find much more ambivalence and complexity in the statements of covictims. The impact of the death penalty and executions on covictims and their ability to attain healing and closure is not so clear cut. By presenting the actual words of capital murder covictims at the time of execution, this inductive, exploratory study provides a novel glimpse at the perspectives of these individuals and their perception of the death penalty process.
Exposure to Child Abuse and Risk for Mental Health Problems in Women
Authors: Schneider Renee , Baumrind Nikki , Kimerling Rachel
Published: October 2007

Risk for adult mental health problems associated with child sexual, physical, or emotional abuse and multiple types of child abuse was examined. Logistic regression analyses were used to test study hypotheses in a population-based sample of women (N = 3,936). As expected, child sexual, physical, and emotional abuse were independently associated with increased risk for mental health problems. History of multiple types of child abuse was also associated with elevated risk for mental health problems. In particular, exposure to all three types of child abuse was linked to a 23-fold increase in risk for probable post-traumatic stress disorder (PTSD). Findings underscore relations between child emotional abuse and adult mental health problems and highlight the need for mental health services for survivors of multiple types of child abuse.
Family Environment and Adult Attachment as Predictors of Psychopathology and Personality Dysfunction Among Inpatient Abuse Survivors
Authors: Riggs Shelley A. , Sahl Gayla , Greenwald Ellen , Atkison Heather , Paulson Adrienne , Ross Colin A.
Published: October 2007

The current study explored the role of early family environment and adult attachment style in explaining long-term outcomes among child abuse survivors. Adult patients (N = 80) in a trauma treatment program were assessed for clinical diagnosis and administered a multiscale questionnaire. Hierarchical regression analyses were significant for dissociative identity disorder (DID), substance abuse, anxiety disorder, posttraumatic stress, somatization, and six personality disorder dimensions. Adult attachment styles were significant predictors of most outcome variables. Of particular note was the strong contribution of attachment avoidance to DID. Five family environment scales (Independence, Organization, Control, Conflict, Expressiveness) also contributed to various psychopathological outcomes. Evidence emerged supporting a mediating role for attachment style in the link between family independence and five personality disorder dimensions.
Preliminary Report on the Accountability Scale: A Change and Outcome Measure for Intimate Partner Violence Research
Authors: Costa Daniela M. , Canady Brittany , Babcock Julia C.
Published: October 2007

The current study investigated the reliability of a new self-report questionnaire assessing accountability for the perpetration of intimate partner violence. The Accountability Scale (AS) is a brief, Likert-type measure designed to assess the degree to which perpetrators acknowledge and accept responsibility for their violent actions. In Study #1, an exploratory factor analysis on a clinical sample revealed two factors: Acknowledging Harm and Internalizing Responsibility. In Study #2, the factor structure was replicated on a community sample using confirmatory factor analysis, revealing an 11-item solution. Factor 1 was related to readiness to change but negatively related to social desirability, suggesting convergent and discriminant validity of that subscale. Factor 2 was negatively related to Factor 1 in the community sample, calling into question the construct of accountability. Preliminary evidence suggests that the AS shows promise as a brief and reliable tool to assess forms of accountability. Future research will examine if the two factors of accountability function as mechanisms of change and outcome measures in intimate partner violence intervention research.
The kinematics of the Tan-Lu Fault zone during the Mesozoic-Palaeocene and its relations with the North China – South China block collision (Anhui Province, China)
Authors: Vergely Pierre , Hou Ming Jin , Wang Young Ming , Mercier Jacques-Louis
Published: October 2007

The Tan-Lu Fault zone (TLFZ), often considered as a major sinistral strike-slip fault, extends in a NE to NNE direction for more than 2,000 km in eastern China. A structural analysis of the southern segment of the TLFZ (STLFZ) and surrounding areas enables us to propose the following evolution of this area during the Mesozoic-Palaeocene. The mid-Triassic NNW-SSE and late Triassic SSW-NNE to SSE-NNW strikes of the stretching lineations in the Zhangbaling massif favour ductile shears in a Zhangbaling metamorphic formation located along a ~NNE-SSW orientated “Tan-Lu margin”; this margin connected two margin segments situated north of the Dabie and Sulu belts. During the Mid-Late Triassic, the continental crust of the South China block (SCB) has been obliquely subducted along this margin below the North China block (NCB). We confirm that the SCB continental crust has been sliced and thrust toward the SSE and propose that the ductile thrusts have merged into the decollements of the sedimentary cover of the platform, forming the thrust-and-fold belt which has acted as a sinistral compressional transfer zone between the Dabie and Sulu collision belts. Thrusting and folding, under a N to NNE compression, affecting Jurassic deposits north and south of the Dabie Shan, indicate that the SCB/NCB collision has continued during the Jurassic. We show that a strike-slip tectonic regime occurred at that time, east of the STLFZ, which initiated as a sinistral continental transform fault between the Dabie and Sulu collisional belts. Dikes and strike-slip faults confirm that a ~NW-SE stretching was active during the basal early Cretaceous (~135–130 Ma), in and around metamorphic domes intruded by plutons. We show that strike-slip faulting, under a NW-SE compression-NE-SW tension, has been active subsequently, until the Aptian-? Early Albian (110/105 Ma), possibly until the Cenomanian (~95 Ma); at that time, the TLFZ has acted as a sinistral continental trans-current fault zone in eastern Asia. Subsequently, normal faulting, under a WNW-ESE extension, indicates that the TLFZ has been a normal fault zone during the Campanian-Palaeocene (~83–55 Ma), possibly until the Early Ypresian (~50 Ma). Sinistral offsets, in the order of several 100 of kilometres, on both sides of the TLFZ have been proposed; the present study does not support such large offset magnitudes.
First occurrence of the genus Dakosaurus (Crocodyliformes, Thalattosuchia) in the Late Jurassic of Mexico
Authors: Buchy Marie-Céline , Stinnesbeck Wolfgang , Frey Eberhard , Gonzalez Gonzalez Arturo H.
Published: October 2007

The fragmentary rostrum of a thalattosuchian is described. The specimen comes from the vicinity of the village of San Juan de los Dolores, next to Los Lirios, Coahuila, northeastern Mexico. Associated ammonites allow to assign the specimen to the Kimmeridgian section (Upper Jurassic) of the La Casita Formation. Because of its massiveness, its cranial architecture and the morphology of its teeth, the specimen is referred to the genus Dakosaurus, but is too incomplete for further determination. The genus is known by few specimens from the Late Jurassic of Europe and Argentina, and was until now unknown from North and Central America. It represents a new but expected element of the assemblage of marine reptiles populating the Mexican Gulf during the Late Jurassic. The specimen is one of the few members of the group preserving in 3 dimensions and visible, the preorbital portion of the rostrum, and especially of the nasopharyngeal canal; it confirms the existence of a large space possibly housing salt glands rostral to the orbits.
Microphytoplankton diversity curves of the Chinese Ordovician
Authors: Li Jun , Servais Thomas , Yan Kui , Su Wenbo
Published: October 2007

Following the publication of a regional diversity curve of the Ordovician organic-walled microphytoplankton (acritarchs) from the Yangtze Platform at the species level [Servais et al., 2004], a diversity curve for China is here presented using all literature data at the generic level. The Chinese curve is a compilation of three separate curves from the three major continental blocks that constituted China in the Ordovician: South China (including the Yangtze Platform), Tarim and North China. The diversity changes can partly be related to sea level changes, both at a regional (South Chinese sea level curve) and at a global level (global curve). The totalised curve for all Chinese localities indicates peaks in diversity that apparently correspond to three sea level highstands at a global level at the early-middle Ordovician boundary (middle “Arenigian”), at the Sandbian-Katian boundary (middle “Caradocian”) and during the Upper Katian (pre-Hirnantian “Ashgillian”) Boda Event [Fortey and Cocks, 2005].
When Can Subscores Have Value?
Authors: Haberman Shelby J.
Published: October 2007

In educational tests, subscores are often generated from a portion of the items in a larger test. Guidelines based on mean squared error are proposed to indicate whether subscores are worth reporting. Alternatives considered are direct reports of subscores, estimates of subscores based on total score, combined estimates based on subscores and total scores, and residual analysis of subscores. Applications are made to data from two testing programs.
SimuSage – the component library for rapid process modeling and its applications
Authors: Petersen Stephan , Hack Klaus , Monheim Peter , Pickartz Ulrich
Published: October 2007

SimuSage is an innovative software tool for process simulation and flowsheeting tasks. Based on ChemApp and its rigorous Gibbs energy minimizing technique, it provides a library of components for the development of highly customized process simulation models. The SimuSage concept is described, and a number of examples from typical application areas such as metallurgy, combustion technology, and other industrial high-temperature processes involving inorganic chemistry are introduced.
Thermodynamic aspects of liquid phase sintering of SiC using Al2O3and Y2O3
Authors: Cupid Damian M. , Fabrichnaya Olga , Seifert Hans J.
Published: October 2007

A thermodynamic dataset for the Al – C – O – Si – Y system was used for calculations of multicomponent, multiphase reactions. Some aspects of the liquid phase sintering of silicon carbide using alumina and yttria sintering additives were analyzed. The phase relations in the SiC – Al2O3, SiC – Al2O3– SiO2and SiC – Y2O3– SiO2systems were calculated. Phase fraction diagrams, isopleths, isothermal sections, and potential phase diagrams are presented to illustrate the reactions between silicon carbide and sintering additives. The effect of Ar inert gas as an additional component and the related volume change of the gas phase were considered. In addition, the influence of surface silica on silicon carbide powder is taken into account.
Thixoforming of non-dendritic AA6061 feedstock produced by low superheat casting with and without a cooling slope
Authors: Birol Yucel
Published: October 2007

Low superheat casting with and without a cooling slope was employed to produce AA6061 thixoforming feedstock. The dendritic features were more frequent in the latter, suggesting that the degeneration of the dendritic structure was promoted by the cooling slope casting process. Minor differences in the primary phase morphology in the as-cast state were no longer evident after partial melting, with nearly equiaxed polygonal grains in all ingots cast with and without a cooling slope. 5 min soaking at 640 °C was identified as the best reheating practice as it provided the smallest grains and the most complete grain boundary wetting. The slugs machined from AA6061 ingots cast from a pouring temperature of 680 °C with and without a cooling slope were both successfully thixoformed into sound parts with no signs of porosity and segregation. The T6 heat treatment produced hardness values as high as 107 HB which compare very favourably with those of the extruded products and are even better than that obtained in the thermomechanically processed feedstock.
Comparative thermodynamic study and phase equilibria of the Bi–Ga–Sn ternary system
Authors: Živković D. , Katayama I. , Gomidželović L. , Manasijević D. , Novaković R.
Published: October 2007

The results of a comparative thermodynamic investigation of the Bi – Ga – Sn system, giving experimentally obtained results and calculated thermodynamic data, are presented in this paper. Oelsen calorimetry was performed for the experimental determination of thermodynamic properties in the section with a molar ratio of Bi: Sn = 1: 3, while the Redlich – Kister – Muggianu method was applied for thermodynamic predicting in the sections with molar ratio Bi: Sn = 1: 3, 1: 1, 3: 1. Thermodynamic parameters – partial and integral molar quantities, as well as gallium activities, were determined at the temperatures of 873 and 973 K. Phase equilibria in the Bi – Ga – Sn ternary system have been studied experimentally – using differential thermal analysis and scanning electron microscopy with energy dispersive X-rays, while the calculation of phase diagram was done according to the CALPHAD method. The phase diagram of the section with molar ratio of Bi: Sn = 1: 3 is given, as well as the phase diagram of the ternary Bi – Ga – Sn system at 373 K.
Grain growth in materials with mobile second-phase particles
Authors: Yu. Novikov Vladimir
Published: October 2007

The grain growth process controlled by particles able to move together with grain boundaries is investigated by means of numerical simulation. The particles either located on grain boundaries or randomly distributed over the material volume are shown to retard grain growth. In the first case, the growth kinetics is described by a power law Dn – D0
n
= kt with the exponent n = 3, at particle volume fractions as low as 0.001. In the case of polycrystals with randomly distributed mobile particles the growth exponent n is larger than 3 and increases with an increase in the particle size or volume fraction.
Innovative Lightweight Technologies Using Power Electronics on Shinkansen High-Speed Electric Multiple Units
Authors: Hagiwara Yoshiyasu , Ishikawa Sakae , Furuya Masashi
Published: October 2007

In 1964, Japan's Tokaido Shinkansen (bullet train) line was the world's first commercial-service, high-speed railway operating at more than 200 km/h. Since then, the Tokaido Shinkansen has demonstrated itself as a successful business and technological advancement. Historically, the Japanese high-speed train system, the Shinkansen, has employed a power-distributed system, an electric multiple-unit (EMU) system, with many advantages such as low axle load and good traction and braking performance. High-speed EMUs take advantage of technological innovations such as electronic technology. An innovative alternating current (AC) drive system, comprising a power converter with a gate turn-off thyristor and AC asynchronous motors, brought a high-performance and lightweight traction system to high-speed EMUs in the 1990s. In EMUs, traction system equipment can be distributed over a train set, and tractive axles throughout the train set can obtain required tractive force without putting a heavy load on the axle. Thus, maximum axle load is reduced, and a lightweight, high-performance train results. Furthermore, recent innovations, such as low switching loss power devices and high-power permanent magnets, have improved AC drive systems of high-speed EMUs of the 21st century. Features and advantages of high-speed EMU systems on the Shinkansen are described, as are recent technological innovations that have given birth to lightweight traction systems, such as the permanent magnet synchronous traction motor and power converters with train–draft-cooling systems. Environmentally friendly aspects of these innovative EMUs are introduced as well.
Lean Railroading for Improving Railroad Classification Terminal Performance
Authors: Dirnberger Jeremiah R. , Barkan Christopher P. L.
Published: October 2007

Although much attention has been focused on the growth of intermodal traffic over the past decade, manifest freight (or carload) traffic is a major revenue generator for railroads. The high potential profitability of carload traffic suggests that railroads should try to grow this segment of traffic further, especially in an era of limited railway capacity. To do this, they must meet the increasing logistical needs of their customers by providing more reliable service. The classification terminal is a key determinant in service reliability of manifest freight. Terminal performance also affects network efficiency. Regression analysis showed that, as average dwell time increased, average manifest train speed decreased. Inadequate terminal capacity is viewed by many as a barrier to improved service reliability and network efficiency. Because terminals can be considered production systems, insight is gained by adapting tools that have led to significant performance improvement in manufacturing. A new approach is introduced: lean railroading. The most important manufacturing process analog to improving terminal capacity is the bottleneck. The train assembly (pull-down) process has been identified as the bottleneck in a majority of classification yards. A sensitivity analysis conducted on three bottleneck management alternatives suggests that pull-down capacity can be increased by as much as 26%, compared with the baseline case without large labor or capital expenses, through better management of the process and its interactions with the system. To maximize efficient use of rail yard infrastructure and resources, more emphasis should be placed on the quality of the classification process, rather than on quantity.
Transportation Tax Ballot Initiatives as Regional Planning Processes
Authors: Goldman Todd
Published: October 2007

Local option taxes increasingly dominate transportation planning and finance in many states. In bypassing the formal metropolitan planning process, these taxes appear to put important regional policy goals at risk. The extent to which key policy issues (e.g., the equity, environmental, and regional transportation impacts of projects) were considered within the planning processes is examined, by drawing from archival research and interviews, for four of these tax measures at a critical stage, when they were becoming dominant in California. How these processes exhibit characteristics associated with “the new regionalism”–consensus building, proactive visioning around untraditional policy goals, informal governance, and network-like organizational approaches–also is described.
Innovative Coordination between States, Metropolitan Planning Organizations, and Tribes in Transportation Planning
Authors: Fu Helena , Mayhew Robin , Bailey Linda , Shoup Lillian
Published: October 2007

Innovative consultation practices between tribes, states, and metropolitan planning organizations (MPOs) within the transportation planning process are highlighted. The FHWA Office of Planning sponsored the development of six case studies that highlight a range of practices implemented by tribal and nontribal governments to advance tribal consultation in statewide and metropolitan transportation planning. These case studies demonstrate that effective tribal consultation results from the identification of common goals and the establishment of ongoing coordination procedures. Researchers obtained input from tribal, federal, state, and local representatives in the six cases; examined current practices and the outcomes of these approaches; and developed lessons learned. Three overarching themes emerged from the case studies: participation and support from tribes, FHWA, FTA, states, and MPOs; funding and resources; and safety issues. As the foundation for effective transportation planning, participation must involve all parties. This process requires commitment and involvement by leadership, communication, and personal meetings and interviews; networking and consortia development, involvement, and representation on appropriate boards and committees; and the critical role that individuals often play in building relationships. Funding and resources also are highlighted. Innovative funding and partnership practices are crucial, as are the resources and technical assistance that states and MPOs provide. Finally, the case studies illustrate the ability to address safety issues through transportation, corridor, and crash-reporting studies and the completion of highway improvements.
The cultures and properties of decaying buildings
Authors: Alexander Catherine
Published: October 2007

This article focuses on controversial plans by the government to rebuild Aisha Bibi, a small, crumbling mausoleum in southeastern Kazakhstan, and thereby hitch its symbolic potency to the nationalist drive. There has never been one commonly accepted account of the building in terms of when and by whom it was created. Nonetheless, it has long been a site of pilgrimage for many different groups and, since the Soviet period, a source of scientific interest. Plans to construct a replica building have brought the multitude of previously co-existing narratives into sharp relief as the new version threatens to oust the others, effectively making one narrative claim exclude others. Further, as is the nature of all representations, the replica will halt and contain the unboundedness and perishability of the mausoleum which, for many local narratives, is an essential part of Aisha Bibi.
Tourism and the revolutionary new man
Authors: Berg Mette Louise
Published: October 2007

Cuba's economic restructuring in the past decade has involved the country's reinsertion into the global tourist market. One of the undesired consequences of the new tourism based economy has been the phenomenon of jineterismo, literally horseback riding, but used to indicate hustling or prostitution. Prostitution is associated with the pre-revolution era and is therefore a sensitive issue for the socialist government. At the same time, sex tourism has become an important source of hard currency income. This article proposes to see jineterismo as a complex social phenomenon that brings issues of race, class, gender and nation into play, ultimately challenging the revolutionary narrative of social and racial equality.
Editorial
Authors: Kalb Don
Published: October 2007

September 2003, while getting on a heavily overpopulated train from Cluj-Napoca to Blaj, Romania, there was not a single quiet compartment available. Or rather: there was only one such place, occupied by just a single young, pretty and overly sexy woman in her mid-twenties. As she sees me looking through the corridor window, she opens the door, asks in English where I am from, and then invites me into her strangely private space. As the train leaves the station she closes the curtains at the corridor side. A few minutes later the door and then the curtains
are opened by the train conductor, a man in his fifties. He comes close to the young woman and points his finger at me. The woman apparently needs to explain who I am and why I am here.
Introduction
Authors: Whitehead Judy , Demirdirek Hülya
Published: October 2007

This introduction explores the contested issue of 'prostitution' and the transnational flow of sex labor. Drawing on the experiences of female migrants described in this issue, we rethink the impact of socialist transition and examine larger themes such as the role of discursive practices in the establishment of national boundaries and in various forms of international intervention. We problematize the 'traffic in women' as well as the conceptualization of and dichotomies surrounding sex labor. Key points in the current debates on transnational sex work are highlighted and an approach is suggested which conceives of agency and structure not in oppositional terms, but as a continuum. Considering the structural conditions imposed by neoliberal policies, we argue that ethnographic accounts can help explain how transnational openings in the market for sex work are internalized as opportunities for young women in post-socialist contexts and how economic liberalization becomes accepted as 'natural' and 'inevitable'.
An alternative approach of UASB dynamic modeling
Authors: Vlyssides Apostolos , Barampouti Elli Maria , Mai Sofia
Published: October 2007

A mathematical model was developed and validated to simulate the dynamic behavior of a UASB reactor. This model took into consideration all the biological and physicochemical reactions. Seven microbial populations were selected using Monod kinetics where inhibition terms were added. The overall biological reactions were determined by first evaluating the reactions for energy and synthesis separately and then adding them together. For each differential time interval, the biomass produced was estimated from the stoichiometry of these reactions. The feasibility of each reaction was determined by thermodynamic calculations. A thermodynamic solution was suggested for the microorganisms that are able to follow more than one catabolic routes and produce several products in spite of the fact that they consume just one substrate. All the reactions that may be performed were realized according to the relative percentage of their free energies. The validation of the model was based on a set of dynamical experiments designed to cover a wide spectrum of operating conditions that are likely to take place in the practical operation of a UASB plant. The model can be a useful tool for the prediction of process performance in transient conditions, even in failure, and can be used to assist in the operation of biogas plants. © 2007 American Institute of Chemical Engineers AIChE J, 53 2007
Antifouling and enhancing pool boiling by TiO2 coating surface in nanometer scale thickness
Authors: Yan Wang , Lin‐lin Wang , Ming‐yan Liu
Published: October 2007

The accumulation of unwanted crystallization deposits on heat transfer surface considerably reduces the efficiency of heat transfer in heat exchangers, especially in the evaporators with vapor–liquid boiling flows. To mitigate the fouling, some measures have been taken including utilizing low‐energy surfaces made by a few kinds of surface‐coating techniques. In this article, novel applications of TiO2 material in inhibiting deposits on heat transfer surface as well as in enhancing pool boiling were developed with nanometer surface engineering method. TiO2 coatings with different layer thicknesses in nanometer scale were prepared by applying vacuum coating technique and were characterized with respect to contact angle, surface free energy, roughness, film thickness, topography by contact angle analyzer, scanning electron microscopy (SEM), and atomic force microscopy (AFM), respectively. Distilled water pool boiling and CaCO3 water solution fouling experiments in pool boiling system were performed on these coating surfaces and antifouling and heat transfer enhancement rules were investigated. The results indicate that all TiO2 coating surfaces can avoid CaCO3 deposition, and fouling induction period of TiO2 coating surface in pool boiling with film thickness of 80 × 10−9 m is about 50 times longer than that of the untreated or polished surface in the present experimental conditions. On the other hand, pool boiling was enhanced on some TiO2 coating surfaces with film thickness in nanometer scale, and heat transfer inhibiting was also observed with certain coating thickness. © 2007 American Institute of Chemical Engineers AIChE J, 2007
Radiation synthesis and characterization of 2‐hydroxyethyl‐methacrylate‐based hydrogels containing di‐ and tri‐protic acid and its application on wastewater treatment
Authors: Abdel‐Aal Samia E. , Hegazy El‐Sayed A. , Abou Taleb M. F. , Dessouki Ahmed M.
Published: October 2007

Radiation‐crosslinked 2‐hydroxyethylmethacrylate/citric acid (HEMA/CAc), 2‐hydroxyethylmethacrylate/tartaric acid (HEMA/TA), and 2‐hydroxyethylmethacrylate/succinic acid (HEMA/Sc) copolymers were prepared by using 60Co γ‐rays. The gel fraction yield and the swelling behavior of the prepared hydrogels were studied. It was shown that increasing irradiation doses was accompanied by an increase in yield of gel fraction and a decrease in swelling degree. The parameters of equilibrium swelling, maximum swelling, initial swelling rate, swelling exponent, and diffusion coefficient of the hydrogels were determined by studying the swelling behavior of the hydrogels prepared. It was seen that the equilibrium swelling degree increases as the content of acid increases, as a result of introducing more hydrophilic groups. When the hydrophilic polymer (acids) varies in the content range of 40–80 mg, swelling exponents (n) decreases, thereby indicating a shift in the water‐transport mechanism from the anomalous (non‐Fickian)‐type to the Fickian‐type. Characterization and some selected properties of the prepared hydrogels were studied, and accordingly the possibility of its practical use in the treatment of industrial wastes such as dyes and heavy metals (Fe, Ni, Co, and Cu) were also studied. The effect of treatment time, pH of feed solution, initial feed concentration, and temperature on the dye and heavy metals uptake was determined. The uptake order for a given metal was HEMA/TA hydrogel > HEMA/CAc > HEMA/Sc hydrogel. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Pervaporation separation of binary and ternary mixtures with polydimethylsiloxane membranes
Authors: Bakhshi Ali , Mohammadi Toraj , Aroujalian Abdolreza
Published: October 2007

This study dealt with the separation of binary water–phenol and water–methanol mixtures and ternary water–phenol–methanol mixtures by pervaporation (PV) with polydimethylsiloxane (PDMS) membranes. The effects of the operating conditions (feed temperature, feed concentration, and feed flow rate) on the separation performance for binary mixtures were investigated. An increase in temperature or concentration increased the total permeation flux and decreased the organic separation factor. In other words, an increase in the temperature or feed organic concentration increased the water flux more significantly than the organic compound flux, which resulted in a separation factor reduction. Also, an increase in the feed flow rate increased the total flux and separation factor because the boundary layer effects diminished. The vapor–liquid equilibrium separation factor (αVLE) and pervaporation separation factor (αPV) values for the PDMS membrane were calculated, and this showed that αPV for the water–phenol mixture was greater than αVLE. This means that the membrane was highly efficient for the PV separation of phenol from dilute aqueous solutions relative to the separation of methanol. This was due to the fact that phenol has a higher solubility parameter than methanol in silicone membranes. To study the effect of a third component on membrane performance, PV experiments were also carried out with water–phenol–methanol mixtures. The results for total permeation flux and the phenol separation factor for PDMS membranes in contact with water–phenol–methanol ternary mixtures are similar to those in contact with water–phenol binary mixtures. The phenol separation factor of the membrane in contact with the ternary mixture was slightly lower than that in contact with the binary mixture. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Surface functionalization by RF plasma deposition of ethylene diamine, acrylonitrile, and acetonitrile
Authors: Jampala Soujanya N. , Sarmadi M. , Manolache S. , Denes F. S.
Published: October 2007

Surface rich in covalently‐bonded amine groups have wide end use applications in biomaterials. This article describes functionalization of stainless steel (SS) surface with reactive chemical groups using RF‐cold‐plasma polymerization of ethylene diamine (ED), acrylonitrile (AN), and acetonitrile (AcN). The effect of RF plasma power and frequency (40 kHz and 13.56 MHz) on surface chemistry was investigated by electron spectroscopy for chemical analysis (ESCA) and FTIR. It was demonstrated that all the plasma‐deposited films consist of secondary and tertiary amines, imines, and amides with a small concentration of nitrile groups present in AN plasma. Significant changes in ED, and AN plasma‐induced molecular fragmentation occur as the plasma conditions are varied. However, AcN plasma polymer chemistry is observed to be independent of RF frequency. Films deposited at 13.56 MHz RF power in continuous mode have higher concentrations of CN linkages, with maximum in ED plasma‐polymerized films. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Preparation of monodisperse poly(vinyl alcohol) microspheres by heterogeneous surface saponification and iodine complex formation
Authors: Lee Se Geun , Lyoo Won Seok
Published: October 2007

Monodisperse poly(vinyl acetate) (PVAc) microspheres with high molecular weight obtained by suspension polymerization of vinyl acetate were saponified in alkaline aqueous solution to keep their spherical structure. The saponification was restricted on the surface of the PVAc microspheres and obtained particles had skin/core structure. Various poly(vinyl alcohol) (PVA) microspheres with different diameters and degrees of saponification (DSs) were obtained. The conversion of PVAc to PVA during the heterogeneous surface saponification time were examined by nuclear magnetic resonance spectroscopy and after 72 h hydrogel type PVA microspheres completely saponified were obtained. The crystal melting temperatures of the microspheres obtained by the saponification were measured a constant value of 238°C irrespective of varying DS, and the peaks became enlarged as reaction time. Iodine complexes were formed in saponified microspheres with DS of 41% and 99% by immersing them in I2/KI aqueous solution and decomposed by the reduction of I2 in the complexes to 2I− using sodium sulfite to confirm whether the skin formed through the saponification was composed of PVA with high VA content. Obviously, characteristic blue color developments owing to I5−‐PVA complexes were observed in both saponified regions and a red in the PVAc core. Consequently, it was concluded that the PVA skins formed by heterogeneous surface saponification had high DSs. Such complexes endowed polymeric microspheres a good radiopacity which would be useful in clinical treatment of vascular diseases and were examined by X‐ray irradiation image. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Synthesis of alkyd resin from jatropha and rapeseed oils and their applications in electrical insulation
Authors: Patel V. C. , Varughese J. , Krishnamoorthy P. A. , Jain R. C. , Singh A. K. , Ramamoorty M.
Published: October 2007

Alkyd resin based on jatropha and rapeseed oils using glycerol, phthalic, and maleic anhydride were synthesized to obtain the resins suitable for electrical applications. These resins were characterized for the physical and electrical properties. Varnishes were prepared using these resins and characterized as per standard methods. In general, both the varnishes prepared from alkyd resin from jatropha and rapeseed oils meet the standard requirements. However, the varnish prepared from rapeseed oil was found to be superior in terms of adhesion, break down voltage, and volume resistivity. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Preparation and performances of ethylene–propylene–diene terpolymer/acrylic rubber reinforced with a dough‐modeling compound
Authors: Wu Weili , Chen Dajun
Published: October 2007

A novel composite was prepared by the addition of a dough‐modeling compound (DMC) reinforcement and an ethylene–propylene–diene terpolymer (EPDM)/acrylic rubber (ACM) matrix. We studied the DMC/EPDM/ACM mass ratio and vulcanizing process by testing the tensile strength, Shore A hardness, elongation at break, and wear and thermal properties. The results show that the mechanical properties, thermal properties, and wear resistance of the composites were good when the DMC/EPDM/ACM mass ratio was 70/25/75 and the cure conditions were 180°C under 10 MPa for 25 min. The crosslinking structure of the composites was studied by IR, and this further proved the interaction between DMC, ACM, and EPDM. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Preparation and characterization of chloromethylated/quaternized poly(phthalazinone ether sulfone ketone) for positively charged nanofiltration membranes
Authors: Yan Chun , Zhang Shouhai , Yang Daling , Jian Xigao
Published: October 2007

Chloromethylated poly(phthalazinone ether sulfone ketone) (CMPPESK) as a novel membrane material was successfully prepared from poly(phthalazinone ether sulfone ketone), with concentrated sulfuric acid as the solvent and catalyst, and chloromethyl octyl ether with lower toxicity as the chloromethylated regent. The effects of the reaction conditions on the preparation of CMPPESKs with different degrees of chloromethylation were examined. The quantity of chloromethyl groups per repeated unit (DCM) of CMPPESK was determined by the method of analysis of the chlorine element, and structures were characterized by 1H‐NMR spectroscopy. The introduction of chloromethyl groups into the polymer chains led to a decrease in the decomposition temperature. With increasing DCM, the initial degradation temperature declined. CMPPESK had good solubility and was soluble in N‐methyl‐2‐pyrrolidone (NMP), N,N‐dimethylacetamide (DMAc), and chloroform. However, quaternized poly(phthalazinone ether sulfone ketone) (QAPPESK) had excellent solvent resistance, was only partly soluble in sulfuric acid (98%), and was swollen in N,N‐dimethylformamide. QAPPESK nanofiltration (NF) membranes had about 90% rejection for MgCl2, and the performance of the NF membrane prepared with DMAc as the solvent was superior to that of the NF membrane prepared with NMP as the solvent. In addition, the rejection to the different salt solutions followed the following sequence: MgCl2 > MgSO4 > NaCl > Na2SO4. Furthermore, the thermotolerance of the QAPPESK NF membrane was examined, and the results show that when the solution temperature rose from 11 to 90°C, the water flux increased more than threefold with stable salt rejection. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Experimental characterization of traditional composites manufactured by vacuum‐assisted resin‐transfer molding
Authors: Cecen Volkan , Sarikanat Mehmet
Published: October 2007

The primary purpose of this study is to investigate the anisotropic behavior of different glass‐fabric‐reinforced polyester composites. Two commonly used types of traditional glass fabrics, woven roving fabric and chopped strand mat, have been used. Composite laminates have been manufactured by the vacuum infusion of polyester resin into the fabrics. The effects of geometric variables on the composite structural integrity and strength are illustrated. Hence, tensile and three‐point‐bending flexural tests have been conducted at different off‐axial angles (0, 45, and 90°) with respect to the longitudinal direction. In this study, an important practical problem with fibrous composites, the interlaminar shear strength as measured in short‐beam shear tests, is discussed. The most significant result deduced from this investigation is the strong correlation between the changes in the interlaminar shear strength values and fiber orientation angle in the case of woven fabric laminates. Extensive photographs of fractured tensile specimens resulting from a variety of uniaxial loading conditions are presented. Another aim of this work is to investigate the interaction between the glass fiber and polyester matrix. The experiments, in conjunction with scanning electron photomicrographs of fractured surfaces of composites, are interpreted in an attempt to explain the interaction between the glass fiber and polyester. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Synthesis, characterization, and comparison of properties of novel fluorinated poly(imide siloxane) copolymers
Authors: Ghosh Anindita , Banerjee Susanta
Published: October 2007

Four new poly(imide siloxane) copolymers were prepared by a one‐pot solution imidization method at a reaction temperature of 180°C in ortho‐dichlorobenzene as a solvent. The polymers were made through the reaction of o‐diphthaleic anhydride with four different diamines—4,4′‐bis(p‐aminophenoxy‐3,3″‐trifluoromethyl) terphenyl, 4,4′‐bis(3″‐trifluoromethyl‐p‐aminobiphenyl ether)biphenyl, 2,6‐bis(3′‐trifluoromethyl‐p‐aminobiphenyl ether)pyridine, and 2,5‐bis(3′‐trifluoromethyl‐p‐aminobiphenylether)thiopene—and aminopropyl‐terminated poly dimethylsiloxane as a comonomer. The polymers were named 1a, 1b, 1c, and 1d, respectively. The synthesized polymers showed good solubility in different organic solvents. The resulting polymers were well characterized with gel permeation chromatography, IR, and NMR techniques. 1H‐NMR indicated that the siloxane loading was about 36%, although 40 wt % was attempted. 29Si‐NMR confirmed that the low siloxane incorporation was due to a disproportionation reaction of the siloxane chain that resulted in a lowering of the siloxane block length. The films of these polymers showed low water absorption of 0.02% and a low dielectric constant of 2.38 at 1 MHz. These polyimides showed good thermal stability with decomposition temperatures (5% weight loss) up to 460°C in nitrogen. Transparent, thin films of these poly(imide siloxane)s exhibited tensile strengths up to 30 MPa and elongations at break up to 103%, which depended on the structure of the repeating unit. The rheological properties showed ease of processability for these polymers with no change in the melt viscosity with the temperature. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008