bluuebunny/crossref_metadata_2025 huggingface dataset:
Explosives, Microbial Degradation of
Authors: Hawari Jalal , Halasz Annamaria
Published: November 2003

Biodegradation of Explosives

(Bio)Remediation Technologies

Environmental and Ecological Risk Assessment

Safety Procedures
Hyperthermophiles
Authors: Gao Jun , Ward Donald F. , Kelly Robert M.
Published: November 2003

Hyperthermophilic Environments

Isolation and Cultivation of Hyperthermophiles

Metabolism of Hyperthermophiles

Genetics of Hyperthermophiles

Microbial Ecology of Hyperthermophiles
Biofilms: Bacterial‐Fungal Biofilms
Authors: Roberts Sara K. , Lappin‐Scott Hilary M.
Published: November 2003

Development of Bacterial‐Fungal Biofilms

Bacterial‐Fungal Biofilm Architecture

Characterizing Bacterial‐Fungal Biofilms

The Occurrence of Bacterial‐Fungal Biofilms

Control of Bacterial‐Fungal Biofilms

Methods to Study Bacterial‐Fungal Biofilms
Viral Disinfection
Authors: Thurston‐Enriquez Jeanette
Published: November 2003

Applications for the Inactivation of Viruses

Virus Structure and Replication

Viral Inactivation by Disinfectants

Factors Affecting Physical and Chemical Disinfection
Endolithic Microorganisms in Arid Regions
Authors: Nienow J. A. , Friedmann E. I. , Ocampo‐Friedmann R.
Published: November 2003

Endolithic Microbial Communities in the Ross Desert of Antarctica

Endolithic Communities in the Coastal Region of Antarctica

Endolithic Communities in Hot Arid Regions

Comparison of Endolithic Communities in Hot and Cold Arid Regions
Microsporidia: Occurrence, Fate and Methodologies
Authors: Dowd Scot E.
Published: November 2003

Microsporidia Spores

Water Sampling

Detection Methods
Biocorrosion: Role of Sulfate Reducing Bacteria
Authors: Beech Iwona B.
Published: November 2003

Fundamental Aspects of Corrosion

Biocorrosion

Sulfate‐Reducing Bacteria

Models of SRB‐Influenced Corrosion
Leptospirosis
Authors: Baranton Guy
Published: November 2003

Bacteriology

Physiology—Metabolism

Epidemiology

Risk Factors (27)

Transmission Mechanisms (27)

Virulence and Pathogenesis (27)

The Disease

Control and Treatment of Leptospirosis (15,27)
Soil Fungi: Nature's Nutritional Network
Authors: Thorn R. Greg
Published: November 2003

Decomposition, Mycorrhizae, and Beyond

Groups of Fungi and Funguslike Organisms

Fungi as Links between Resources and Trophic Groups, over Distance and Time
Weathering, Microbiol
Authors: Sand Wolfgang , Jozsa Peter‐Georg , Mansch Reiner
Published: November 2003

Microorganisms Involved in Biodeterioration

Microbial Mechanisms Contributing to Bioweathering

Materials, Properties, and Examples of Complex Weathering Processes

Simulation of Microbial Weathering
Enteroviruses in Water: Concentration and Detection
Authors: Goyal Sagar M.
Published: November 2003

Electronegative Filters

Comparative Studies

Electropositive Filters

Other Media

Factors Influencing Virus Concentration

Second‐Step Concentration

Molecular Methods of Virus Detection

Inhibitors of RT‐PCR
Stream Microbiology
Authors: Leff Laura G.
Published: November 2003

Physical Features of Streams

Streams and their Watershed

Stream Food Webs

Viruses

Bacteria

Protozoa

Fungi

Algae
Wastewater Stabilization Ponds
Authors: Mara Duncan
Published: November 2003

Bacterial Populations

Algal Populations

Photosynthetic Bacteria

Removal of Excreted Pathogens
Extracellular Polymeric Substances (EPS): Structural, Ecological and Technical Aspects
Authors: Flemming H.‐C. , Wingender J.
Published: November 2003

Composition of EPS

Ecological Function of EPS

EPS in Biofouling, Bioweathering, and Biocorrosion

Sorption Properties

EPS in Biotechnology

Outlook
Mycobacterium AviumComplex
Authors: Falkinham Joseph O.
Published: November 2003

TheM. AviumComplex

Epidemiology of theM. AviumComplex

Ecology of theM. AviumComplex

Transmission of theM. AviumComplex

Molecular Epidemiology of theM. AviumComplex

Methods for Working with theM. AviumComplex

Growth and Physiological Ecology of theM. AviumComplex

Disinfection Resistance of theM. AviumComplex

Antimicrobial Resistance of theM. AviumComplex
Enteroviruses: Basic Biology and Diseases
Authors: Gerba Charles P.
Published: November 2003

General Properties

History

Epidemiology

Growth in Cell Culture

Identification

Host Range

Infectivity

Immunity

Pathogenesis

Asymptomatic Infections

Secondary Transmission

Illnesses Caused by Enteroviruses

Paralysis

Perinatal and Neonatal Infections

Herpangina

Aseptic Meningitis

Nonspecific Febrile Illness

Exanthems (Eruption of the Skin)

Respiratory Illness

Acute Hemorrhagic Conjunctivitis (AHC)

Diabetes

Pleurodynia (Bornholm Disease)

Myocarditis

Diseases Associated with the Immunocompromised

Other Illnesses

Incidence of Enterovirus Infections

Economic Impact

Water and Food‐Borne Outbreaks
Bioaugmentation
Authors: Deflaun Mary F. , Steffan Robert J.
Published: November 2003

Remediation Hierarchy

Organisms for Bioaugmentation

Improving Organisms for Bioaugmentation

Constitutive Degradative Activity

Enhanced Transport

Energy Enrichment

Mixed Cultures and Consortia

Examples of Type 1 Bioaugmentation

Examples of Type 2 Bioaugmentation
Soil Genetic Ecology
Authors: Castro Hector , Ogram Andrew
Published: November 2003

Methods

Environmental Genomics and the Future of Soil Genetic Ecology
Rhizosphere, Bacterial Phytostimulators in
Authors: Burdman Saul , Kadouri Daniel , Jurkevitch Edouard , Okon Yaacov
Published: November 2003

Mechanisms of Action of Phytostimulating Bacteria

Bacterial Features for Rhizosphere Competence

Interactions of PGPR with Biotic and Abiotic Factors

Inoculation with PGPR in a Dense Microbial Background

Molecular Methodology for Tracking Introduced Phytostimulators

Commercial Products: Present and Future
Picoplankton, Freshwater
Authors: Callieri Cristiana , Stockner John
Published: November 2003

Historical and Methodological Perspectives

Current Methods for the Study of Autotrophic Picoplankton

Autotrophic Species Composition

Ecology of Autotrophic Picoplankton
Salivary Gland Cancers
Authors: Califano Joseph , Spiro Ronald H.
Published: November 2003

Malignant salivary gland tumors are remarkable for their relative infrequency as compared to other solid tumors, and their wide diversity in histologic appearance, clinical presentation, and biologic behavior. By virtue of the slow growth rates of some of these tumors, posttreatment surveillance must continue for a decade or more in order to accrue reliable data regarding locoregional control and survival. Fortunately, useful prognostic information can be derived from assessment of clinical stage, and tumor histology.
Gastric Cancer
Authors: van Krieken J. Han J. M. , Sasako Mitsuru , van de Velde Cornelis J.H.
Published: November 2003

The incidence of gastric cancer is decreasing worldwide, but the prognosis is still generally poor. Insight in pathogenesis (the role of Helicobacter Pylori and Epstein‐Barr virus) and molecular genetics (p53 en RAS mutations) has increased in recent years. Important new data exist on treatment: the role of local surgical treatment, extended lymphadenectomy, and chemotherapy. Outcome is clearly dependent on many factors, but complete surgical excision is still central in the treatment. This chapter deals with clinical, pathological, and genetic factors that are related to survival, especially those that can influence clinical management. An important caveat has been formulated recently: criteria to diagnose cancer of the stomach vary, clearly leading to differences in patient populations in studies. In particular, this might partially explain the higher incidence and better prognosis of gastric cancer in Japan. But then, when staged similarly using the same prognostic factors, there was no difference between the prognosis for German and Japanese patients. Where prior gastric surgery is concerned (gastric stump carcinoma) prognosis is very poor, but dependant on stage. Histology and DNA index in these cases are the same as for other upper‐third stomach cancer cases. In a retrospective study on 2654 patients from Japan, it was found that from the early 1960s to the early 1980s the percentage of proximally located tumors increased from 17% to 27% and signet‐ring‐cell carcinoma increased from 2% to 22%. Although proximally located tumors behaved more aggressive, survival was more associated with stage than with primary site in the stomach.
Colorectal Cancer
Authors: Hobday Timothy J. , Erlichman Charles
Published: November 2003

Colorectal cancer is the second leading cause of site‐specific cancer mortality in Western nations. Over 130,000 new cases and 56,500 deaths were expected in the United States in 1998. Approximately 70–80% of patients will present with apparently localized disease that is surgically resectable. A proportion of these patients harbor occult micrometastases and will relapse after initial therapy. Randomized, Phase III clinical trials evaluating adjuvant chemotherapy (combined with radiotherapy in rectal cancer) for patients with local/regional lymph‐node involvement have clearly shown some of these patients can be cured with adjuvant therapy.

A recent pooled analysis as well as the individual prospective randomized clinical trials of adjuvant chemotherapy in patients with Stage II disease (no involvement of local/regional lymph nodes) have not clearly shown a survival benefit in these patients. Yet a significant minority of these patients will relapse and eventually die of their disease. A review by the National Surgical Adjuvant Breast and Bowel Project (NSABP) of four consecutive adjuvant chemotherapy trials in Stages II and III colorectal cancer argues that adjuvant chemotherapy does improve survival for Stage II patients. The use of molecular markers that have prognostic significance in addition to pathologic and clinical factors has the potential to identify high‐risk patients who may benefit from therapy. This may allow treatment of those at highest risk while sparing those with minimal risk the toxicity and expense of adjuvant chemotherapy.

Prognostic factors can also serve a useful role in advanced disease. Some factors may be predictive of response to therapy, thereby aiding in the choice of palliative treatment. In a small subset of patients with metastatic colorectal cancer, patient‐and tumor‐related factors impact on the potential for curative resection of metastatic disease.
Cutaneous Malignant Melanoma
Authors: Heenan Peter J. , Yu Lawrence L. , English Dallas R.
Published: November 2003

The most important prognostic factor in patients with cutaneous malignant melanoma (CMM) is the anatomic extent of disease and, specifically, presence of metastasis. In those patients without clinical metastasis at the time of diagnosis, direct measurement of tumor thickness by the method of Breslow remains the most accurate single prognostic factor. The improvement in survival rates recorded over time has been associated with a decrease in tumor thickness, and geographical differences in prognosis have been related to differences in tumor thickness. Furthermore, the prognostic effects of such features as the histologic type and level of invasion are overridden by the effect of tumor thickness. The measurement of tumor thickness by means of an ocular micrometer is also more reproducible among pathologists than the recognition of histologic subtypes and the assessment of level of invasion according to anatomical landmarks, both of which are more prone to subjective interpretation and interobserver variation.

It is also apparent, however, that although tumor thickness remains the best available single prognostic index, it provides only a rough guide to the outcome for an individual patient. Increasing efforts have been made, therefore, to discover more accurate means of assessing the risk of metastasis in patients with melanoma by using multifactorial prognostic models and by searching for molecular markers of metastatic potential. Prognostic models, however, although yielding impressive results in some studies, may not always be accurate in their application to individual patients, and the search for molecular markers of metastatic potential, although providing initially promising results, has as yet failed to identify prognostic factors that are as accurate or as practically applicable as the measurement of tumor thickness.
Vulvar Cancer
Authors: Lou Benedet J. , Ehlen Thomas G.
Published: November 2003

Vulvar cancer is an uncommon malignancy accounting for approximately 4–5% of all gynecologic cancers. It used to be thought of as predominantly a disease of the elderly, although reports of young, reproductive‐age‐group women with this disease increasingly appear in the literature. The external location of the vulva should prompt early presentation, but traditionally significant delays in diagnosis have been associated with this cancer.

The past decade has seen a better understanding of the prognostic factors for vulvar cancer, which, in turn, has led to a more individualized approach to therapy. This has led to less aggressive surgery in the earlier stage of the disease with better cosmetic and functional results. It might be expected that, with the increasing life expectancy in many countries and the concomitant aging of the population, an increase in the number of cases being diagnosed would occur in the future.
Endometrial Cancer
Authors: Lou Benedet J. , Miller Dianne M.
Published: November 2003

In many industrialized countries, endometrial cancer has surpassed cervical cancer as the most common form of malignancy affecting the female genital tract. This has occurred due to the effectiveness of screening programs in reducing both the incidence and mortality rates for cervical cancer. Improvement in life expectancy for many women also has led to an increased number of patients being diagnosed with endometrial cancer, which is predominantly a disease of postmenopausal women.

Endometrial cancer most often presents with the symptom of postmenopausal bleeding. Because this manifestation is often found early in the course of the disease and is significantly alarming, women generally present themselves promptly to their physicians for investigation. The majority of endometrial cancers are thus diagnosed as stage I lesions. In certain situations, however, this condition has the potential to behave in an aggressive fashion, resulting in recurrence and ultimately death. The identification of those factors that place patients at high risk for recurrence has been the primary focus of much of the research on this condition in the past 20 years.

Although endometrial cancer is predominantly a disease of postmenopausal women, approximately 20–25% of cases will occur before menopause and a further 5% occur before age 40. Obesity, particularly upper body obesity, nulliparity, and late menopause have all been associated with an increase in risk for endometrial cancer. Use of exogenous unopposed estrogen and tamoxifen have also been associated with an increased risk for the development of endometrial cancer. Use of oral contraceptive tablets and smoking, however, have been associated with a decrease in the risk for endometrial cancer and women who develop endometrial cancer while on exogenous estrogen appear to have favorable prognosis.
Pharynx
Authors: Sobin L.H. , Wittekind Ch.
Published: November 2003

The TNM system is used to describe and classify cancer stages and progression based on the assessment of three components:

T

The extent of the primary tumour

N

The absence or presence and extent of regional lymph node metastasis

M

The absence or presence of distant metastasis.

TNM classification for the above site is described under the following headings:

Rules for classification with the procedures for assessing T, N, and M categories; additional methods may be used when they enhance the accuracy of appraisal before treatment

Anatomical sites and subsites where appropriate

Definition of the regional lymph nodes

TNM Clinical classification

pTNM Pathological classification

G Histopathological grading

Stage grouping

Summary
Ampulla of
V
ater
Authors: Sobin L.H. , Wittekind Ch.
Published: November 2003

The TNM system is used to describe and classify cancer stages and progression based on the assessment of three components:

T

The extent of the primary tumour

N

The absence or presence and extent of regional lymph node metastasis

M

The absence or presence of distant metastasis.

TNM classification for the above site is described under the following headings:

Rules for classification with the procedures for assessing T, N, and M categories; additional methods may be used when they enhance the accuracy of appraisal before treatment

Anatomical sites and subsites where appropriate

Definition of the regional lymph nodes

TNM Clinical classification

pTNM Pathological classification

G Histopathological grading

Stage grouping

Summary
Preparing instructors for online instruction
Authors: Fein Adam D. , Logan Mia C.
Published: November 2003

The challenges and opportunities that online education and training present for instructors is discussed, along
with strategies that can help instructors succeed in online environments.
Meeting the needs of consumers: Lessons from postsecondary environments
Authors: Huber Herbert E. , Lowry Jean C.
Published: November 2003

Basing their remarks on personal experience, two recent graduates of an online master's degree program
share their insights on this educational technology from the consumer's perspective, including benefits,
challenges, and recommendations for students and institutions.
Morphology evolution of immiscible LDPE/PVC blends in the presence of compatibilizer and phase dispersant
Authors: Fang Zhengping , Ma Guowei , Liu Chao , Xu Chengwei
Published: November 2003

Phase dispersion and coalescence in low‐density polyethylene (LDPE)/polyvinyl chloride (PVC) (70/30) blends influenced by compatibilizer and phase dispersant was studied. It was found that the morphology evolution of blends is sensitive to not only processing conditions (shear strength and mixing time) but also the added compatibilizer or phase dispersant. In our conditions, the stable phase morphology of each blend is obtained after mixing 15–25 min. In addition, the dispersed PVC phase in blends is easy to aggregate when the mixing rotor speed changed from high to low for the binary blends. As a compatibilizer, chlorided polyethylene (CPE) or nitrile rubber (NBR) can stabilize the morphology and hinder the coalescence of the dispersed PVC phase when added to the blends. However, the phase dispersant butadiene rubber (BR) or styrene butadiene rubber (SBR) could not stabilize the phase structure, although it could accelerate phase dispersion. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 763–772, 2004
Tannin antioxidant characteristics in leather versus leather light stability: Models
Authors: Pizzi A. , Simon C. , George B. , Perrin D. , Triboulot M. C.
Published: November 2003

The variation of leather color as a function of aging time on prolonged irradiation with UV light of the leather produced by tanning with different polyflavonoid and hydrolyzable vegetable tannins is reported. A predictive model and two equations for the variation of leather color as a function of UV‐irradiation time and as a function of the different vegetable tannins used was also established. This technique appears to describe well the overall phenomenon of oxidation and color change in situ observable in vegetable‐tanned leathers. The variation of leather color as a function of aging time on prolonged irradiation with UV light of the leather produced based on different vegetable tannins was found to be composed of two main effects: The first one of these is the darkening reaction of the leather. This is due to the formation of quinones on the phenolic structure of the vegetable tannin. The second one is the leather‐lightening reaction due to the photodegradation of the system. These two phases were equated and correlated with the radical uptake reaction and radical stabilization/decay reaction observed by ESR for UV‐irradiation of pure tannin in the solid form and of the leather produced using the same. Thus, correlation among the antioxidant capability of tannins in the solid form, their antioxidant capability once included in the leather, and the color variation (darkening and lightening) of leather by colorimetry was established. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 1030–1040, 2004
Complex processing–morphology interrelationships during the reactive compatibilization of blends of poly(butylene terephthalate) with epoxide‐ containing rubber
Authors: Martin P. , Devaux J. , Legras R. , Leemans L. , Van Gurp M. , Van Duin M.
Published: November 2003

Reactive processing of blends of poly(butylene terephthalate) (PBT) with the ethene–(methyl acrylate)–(glycidyl methacrylate) terpolymer (E–MA–GMA) is known to present a very complex reactivity since two competitive reactions take place spontaneously during melt blending, that is, blend compatibilization and rubber‐phase crosslinking. In this article, the effects of several processing parameters, such as the shear rate, the processing temperature, and the matrix viscosity, on the reactive processing of those blends were investigated in terms of the blend morphology and of the amount of copolymer formed at the blend interface. It was shown that the morphology development could be divided in two successive regimes: In the early stages of the mixing process, the particle size is essentially determined by the physical dispersion process, that is, breakup and coalescence, while, at longer mixing times, a further decrease in particle size is obtained as a result of the compatibilization reactions. The shift between the two regimes is progressive and intimately related to the processing conditions. Despite such a complexity, not only the blend morphology but also the elastic properties of the rubber particles can be controlled in a broad range by an adequate adjustment of the relative kinetics between both physical and chemical processes. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 703–718, 2004
Thermal decomposition kinetics of thermotropic copolyesters made from trans‐p‐hydroxycinnamic acid and p‐hydroxybenzoic acid
Authors: Tang Wei , Li Xin‐Gui , Yan Deyue
Published: November 2003

A series of thermotropic copolyesters were synthesized by direct thermal melt polycondensation of p‐acetoxybenzoic acid (PHB) with trans‐p‐acetoxycinnamic acid (PHC). The dynamic thermogravimetric kinetics of the copolyesters in nitrogen were analyzed by four single heating‐rate techniques and three multiple heating‐rate techniques. The effects of the heating rate, copolyester composition, degradation stage, and the calculating techniques on the thermostability and degradation kinetic parameters of the copolyesters are systematically discussed. The four single heating‐rate techniques used in this work include Friedman, Freeman–Carroll, Chang, and the second Kissinger techniques, whereas the three multiple heating‐rate techniques are the first Kissinger, Kim–Park, and Flynn–Wall techniques. The decomposition temperature of the copolyesters increases monotonically with increasing PHB content from 40 to 60 mol %, whereas their activation energy exhibits a maximal value at the PHB content of 50 mol %. The decomposition temperature, activation energy, the order, and the frequency factor of the degradation reaction for the thermotropic copolyester with PHB/PHC feed ratio of 50/50 mol % were determined to be 374°C, 408 kJ/mol, 7.2, and 1.25 × 1029 min−1, respectively. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 445–454, 2004
Methyl methacrylate and acrylamide crosslinked macroporous copolymers
Authors: Nikolić Ljubiša , Skala Dejan , Nikolić Vesna , Stamenković Jakov , Babić Dragan , Ilić‐Stojanović Snežana
Published: November 2003

In this work the synthesis of a crosslinked macroporous copolymer was effected from methyl methacrylate and acrylamide. The synthesis process began with emulsion prepolymerization, followed by sol–gel copolymerization until a hard block was obtained. Determination of the properties of the obtained material was carried out by FTIR, mercury porosimetry, and SEM microscopy. The material was characterized by a porous structure with open pores. The macroporous copolymer obtained can be used for polymer–analog reactions and the transformation of amide and ester groups into acyl azide groups. It can be used as a hard inert support for the immobilization of enzymes, or other proteins, by condensation of acyl azide group on polymer with the free amino group from the base amino acid of enzyme/protein. For the immobilization of microorganisms it can be used by vacuum diffusion of microorganism suspension into the porous structure, without active group transformation reactions. With microorganisms in the polymer pores, microorganism colonies form within the copolymer by microbial fermentation. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 387–395, 2004
Influence of electron beam irradiation on properties of fluorine‐containing poly(aryl ether ketone)s
Authors: Kimura Kunio , Tabuchi Yumi , Nishichi Ai , Yamashita Yuhiko , Okumura Yasunori , Omote Kazushi , Morita Yosuke , Kudo Hisaaki
Published: November 2003

The influence of electron beam irradiation on the properties of fluorine‐containing poly(aryl ether ketone)s (F‐PEK), derived from 2,3,4,5,6‐pentafluorobenzoic acid, was examined. Irradiation was performed with an electron beam at a dose of 3.63 × 103 Gy s−1 for which the corresponding doses were 29.0, 51.0, and 94.5 MGy. Tensile strength at break increased up to a dose of 29.0 MGy and then decreased very slightly with irradiation. Elongation at break was more susceptible to irradiation and decreased drastically to one tenth at a dose of 29.0 MGy. Young's modulus was enhanced by the irradiation. F‐PEKs were changed from elastic materials to strong and brittle materials by irradiation. Relaxation of the viscoelastic property shifted toward higher temperature by irradiation. These tensile and viscoelastic property changes were attributed to the formation of a bulkier and more rigid structure by crosslinking. The fluorine atoms attached to the 1,4‐phenylene moiety in F‐PEKs were surprisingly susceptible to the irradiation and were completely lost at a dose of 29.0 MGy. The π‐electron conjugated aromatic structure was concurrently developed during irradiation. Further, polar functional groups such as carboxyl group and ester group were generated by chain scission and rearrangement. The F‐PEKs retained their good transparency and the thermal stability was significantly improved after irradiation. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 157–166, 2004
Modeling of creep and shrinkage behavior of polymeric films used in magnetic tapes
Authors: Bhushan Bharat , Jayantha‐Rao Ravichander
Published: November 2003

For ever increasing high recording densities of magnetic tape drives, improved dimensional stability of the polymeric films used as magnetic tape substrates is required. During storage and use, creep and shrinkage occur simultaneously and it needs to be minimized. To obtain constitutive relationships for creep and shrinkage, these contributions need to be separated and modeled. A mathematical model based on Kelvin–Voigt models has been developed to characterize simultaneous creep and shrinkage behavior to obtain the constitutive relationships for creep and shrinkage. Experiments have been performed to separate out creep and shrinkage effects and this model has been used to compensate the effect of shrinkage on creep data and to get true creep data. The experimental creep and shrinkage data of various films have been modeled to obtain viscoelastic parameters. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 78–88, 2004
Synthesis, characterization, and swelling responses of poly(N‐isopropylacrylamide)‐ and hydroxypropyl cellulose‐based environmentally sensitive biphasic hydrogels
Authors: Chauhan Ghanshyam S. , Lal Harinder , Mahajan Swati
Published: November 2003

Thermosensitive networks based on hydroxypropyl cellulose and N‐isopropylacrylamide crosslinked with N,N‐methylene bisacrylamide were synthesized by a simultaneous gamma radiation technique. The network yield was optimized by the variation of reaction parameters such as the total radiation dose, concentration of crosslinker and monomer, and amount of water. The hydrogels had a biphasic structure and good mechanical strength, even in the fully swollen state, and could be synthesized in any shape and size. Volume transitions as a function of time and temperature were studied for these hydrogels in water, and the effects on swelling in different media such as 0.5N NaOH, 0.5N HCl, and 5% NaCl at the optimum time and temperature were also studied. The response of the hydrogels to these diverse changes in the swelling media was observed, and the volume transitions due to environmental changes in the hydrogels were not sharp and discontinuous as a maximum volume collapse occurred at a temperature higher than the reported lower critical solution temperature of 32.5°C for N‐isopropylacrylamide. These hydrogels were environmentally sensitive and responded to changes in their thermal and ionic environment and have potential applications in diverse fields such as drug delivery, enzyme technology, and environmental management. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 479–488, 2004
Blends composed of poly(N‐isopropylacrylamide) and an ethylene/vinyl alcohol copolymer: Thermal and morphological studies
Authors: Mano Valdir , Ribeiro e Silva Maria Elisa Scarpelli , Barbani Niccoletta , Giusti Paolo
Published: November 2003

Blends of poly(N‐isopropylacrylamide) (PNIPAM) and an ethylene/vinyl alcohol copolymer (EVAL) were obtained through casting from dimethyl sulfoxide (DMSO) solutions and phase inversion in 50/50 DMSO/H2O solutions. The miscibility and morphology of the PNIPAM/EVAL blends were investigated with thermal and morphological analysis. Differential scanning calorimetry indicated that the crystallinity of EVAL decreased with increasing PNIPAM content and that the blends cast from DMSO/H2O solutions were miscible in the melt state. Measurements of the melting point depression allowed the determination of the interaction energy density (B) and Flory–Huggins interaction parameter (χ12) with the Nishi–Wang equation. The negative B and χ12 values obtained were examined in terms of the specific intermolecular interactions between the polymers. Scanning electron micrographs revealed that blends obtained by the casting method led to dense membranes, whereas the phase‐inversion method rendered typical macroporous membranes. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 501–505, 2004
Effect of a chain extender on the crystallization behavior of nylon 66
Authors: Ding Xuejia , Rong Jianhua , Xu Riwei , Yu Dingsheng , Yang Zhenzhong
Published: November 2003

The crystallization behaviors and crystalline morphologies of initial and chain‐extended nylon 66 samples were studied with differential scanning calorimetry and polarizing microscopy, respectively. The crystallization rate increased and the size of the spherulites decreased with chain‐extension. In addition, a two‐peak behavior was observed in chain‐extended nylon 66. These results showed that for the chain‐extended nylon 66, there was heterogeneous nucleation during crystallization. Therefore, the chain extender possibly functioned as a nucleating agent at the same time. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 68–71, 2004
Facile synthesis of novel optically active poly(amide‐imide)s containing N,N′‐(pyromellitoyl)‐bis‐l‐phenylalanine diacid chloride and 5,5‐disubstituted hydantoin derivatives under microwave irradiation
Authors: Faghihi Khalil , Zamani Khosrow , Mirsamie Azzizullah , Mallakpour Shadpour
Published: November 2003

Pyromellitic dianhydride (1,2,4,5‐benzenetetracarboxylic acid 1,2,4,5‐dianhydide) (1) was reacted with L‐phenylalanine (2) in a mixture of acetic acid and pyridine (3 : 2) at room temperature, then was refluxed at 90–100°C and N,N′‐(Pyromellitoyl)‐bis‐L‐phenylalanine diacid (3) was obtained in quantitative yield. The imide‐acid (3) was converted to N,N′‐(Pyromellitoyl)‐bis‐L‐phenylalanine diacid chloride (4) by reaction with thionyl chloride. Rapid and highly efficient synthesis of poly(amide‐imide)s (6a–f) was achieved under microwave irradiation by using a domestic microwave oven from the polycondensation reactions of N,N′‐(Pyromellitoyl)‐bis‐L‐phenylalanine diacid chloride (4) with six different derivatives of 5,5‐disubstituted hydantoin compounds (5a–f) in the presence of a small amount of a polar organic medium that acts as a primary microwave absorber. Suitable organic media was o‐cresol. The polycondensation proceeded rapidly, compared with the conventional melt polycondensation and solution polycondensation, and was almost completed within 10 min, giving a series of poly(amide‐imide)s with inherent viscosities about 0.28–0.44 dL/g. The resulting poly(amide‐imide)s were obtained in high yield and are optically active and thermally stable. All of the above compounds were fully characterized by means of FTIR spectroscopy, elemental analyses, inherent viscosity (ηinh), solubility test and specific rotation. Thermal properties of the poly(amide‐imide)s were investigated using thermal gravimetric analysis (TGA). © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 516–524, 2004
Crude and modified corncobs as complexing agents for water decontamination
Authors: Clave E. , François J. , Billon L. , Sèbe G. , Jéso B. De , Guimon M. F.
Published: November 2003

The ability of corncobs to retain copper ions was studied with respect to the origin of the materials (inner or outer parts of the cobs), the granulometry, the pH, and chemical modifications with maleic anhydride (MA) and succinic anhydride (SA). Esterification, characterized by Fourier transform infrared and X‐ray photoelectron spectroscopy, led to a large increase in copper retention in comparison with unmodified corncobs. The retention capacity was improved up to 6 times with SA‐modified corncobs at pH 5. The adsorption behavior of MA‐ and SA‐grafted samples, with respect to copper, appeared to be different at pH 4 and pH 5, and this was attributed to a difference in the pKa values of the grafted carboxylic functions. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 820–826, 2004
Study of compartmentalization in the polymerization of miniemulsions of styrene and butyl methacrylate
Authors: Ouzineb K. , Graillat C. , McKenna T. F.
Published: November 2003

Different surfactant and costabilization systems were studied for the miniemulsion polymerizations of styrene (St) and of butyl methacrylate (BMA). It was found that the combination of sodium dodecyl sulfate, Triton X‐405, and octadecyl acrylate yielded excellent results. With this system all of the droplets initially present in the reactor polymerized. This stabilization system was then used in the study of compartmentalization of the monomer droplets in miniemulsion polymerization. Blends of BMA and St miniemulsions were prepared separately and polymerized together to study mass transfer in this system. It was observed that no matter is exchanged between the different phases. This compartmentalization was also demonstrated and exploited by producing a bimodal molecular weight distributions latex, achieved with a semicontinuous process. The lower MWD was created by adding a second miniemulsion containing a transfer agent. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 115–124, 2004
Phase structural analyses of polyethylene coatings on high‐density papers. III. Determination of the crystallite thicknesses by T1 measurements
Authors: Furuheim Knut Magne , Axelson David E. , Antonsen Henrik W. , Helle Torbjørn
Published: November 2003

Two different extrusion‐coating qualities of polyethylene, namely LDPE and HDPE, were coated on high‐density papers. Differences were observed with respect to their response to storage and low temperature heat treatment. HDPE does not respond to storage at ambient temperature and heat treatment in the same way as LDPE. The LDPE‐coating exhibits an increase in the monoclinic crystalline fraction at the paper surface as a result of heat treatment. The nature of this response appears to be a result of adhesion to a paper surface, the properties of this surface, orientation of polymer chains, and chain mobility differences. The increase of the monoclinic fraction is shown to relate to an increase of the mean crystallite thickness and initiation of new crystallites at the paper surface. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 235–241, 2004
RF sputter deposition of poly(tetrafluoroethylene) films as masking materials for silicon micromachining
Authors: Bodas Dhananjay S. , Patil Sheetal J. , Mandale A. B. , Gangal S. A.
Published: November 2003

Polymers have been studied extensively because of their wonderful array of properties. Their properties can be tailored by many means and can be made useful in many ways. Polymers can be crosslinked or branched and can provide different properties, such as conduction and passivation. This study dealt with the RF sputter deposition of poly(tetrafluoroethylene) (PTFE) films with the aim of using them as masking materials during the fabrication of various micromachined structures. The films were deposited on silicon substrates at different plasma powers (100, 150, and 200 W) for a constant deposition time (60 min). To test the masking properties, the deposited films were immersed in a 20 wt % aqueous KOH solution at 80°C for 60 min. The films showed lower contact angles and interfacial tension, and this indicated good adhesion of the films to the silicon substrates. Good adhesion is an essential quality of masking materials during micromachining. The structural properties of the as‐deposited and etched films were studied with Fourier transform infrared and X‐ray photoelectron spectroscopy. These indicated that the bonding groups and binding energies of CF and CCF matched the reported values well. Furthermore, the presence of CF and CCF bonds, even after the etching of silicon substrates in highly alkaline KOH solutions for 60 min, showed that the PTFE films remained unchanged in the etchant and, therefore, could function as good masking materials during the fabrication of micromachined structures. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 1183–1192, 2004
In situfiber‐reinforced composites from blends containing polypropylene and polycaprolactone
Authors: Semba Takeshi , Kitagawa Kazuo , Endo Satoshi , Maeda Kazunori , Hamada Hiroyuki
Published: November 2003

Our study was focused on the presupposition that morphology control in immiscible polymer blend could give rise to reinforcement in composites. To investigate the effects of shear and elongational flow in polymer processing, observation of the mechanical properties and the morphology of the polypropylene/polycaprolactone (PP/PCL) blend system was performed. PP/PCL sheets were fabricated by means of a single‐screw extruder equipped with a slit‐type die to which high shear and elongational stresses were applied. For the sake of comparison, a second series of composites of identical composition was compression molded with a hot‐press machine that transmits lower shear and elongational stresses. The results indicate that the extruded sheets have better mechanical properties than those of the compression‐molded sheets, a result attributed to the generation ofin situdispersed long fiber minor phases and cocontinuous phases in the extruded composites. The differences in the crystallization behavior of the fibrous and spherically shaped components were indicated clearly by DSC curves. A PP crystalline peak indicative ofin situPP fiber formation is conspicuous around 980 cm−1(PP crystalline band) in the FTIR spectrum. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 833–840, 2004
Hydrogen bonding effect on the poly(ethylene oxide), phenolic resin, and lithium perchlorate–based solid‐state electrolyte
Authors: Chen Hsien‐Wei , Jiang Chang‐Hung , Wu Hew‐Der , Chang Feng‐Chih
Published: November 2003

The interaction behavior of solid‐state polymer electrolytes composed of poly(ethylene oxide) (PEO)/novolac‐type phenolic resin and lithium perchlorate (LiClO4) was investigated in detail by DSC, FTIR, ac impedance, DEA, solid‐state NMR, and TGA. The hydrogen bonding between the hydroxyl group of phenolic and ether oxygen of the PEO results in higher basicity of the PEO. The higher basicity of the ether group can dissolve the lithium salts more easily and results in a greater fraction of “free” anions and thus higher ionic conductivity. DEA results demonstrated that addition of the phenolic increases the dielectric constant because of the partially negative charge on the ether group induced by the hydrogen bonding interaction between ether oxygen and the hydroxyl group. The study showed that the blend of PEO(100)/LiClO4(25)/phenolic(15) possesses the highest ionic conductivity (1.5 × 10−5 S cm−1) with dimensional stability. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 1207–1216, 2004
PEEKWC ultrafiltration hollow‐fiber membranes: Preparation, morphology, and transport properties
Authors: Tasselli F. , Jansen J. C. , Drioli E.
Published: November 2003

A series of hollow‐fiber membranes was produced by the dry–wet spinning method from PEEKWC, a modified poly(ether ether ketone) with good mechanical, thermal, and chemical resistance. The fibers were prepared under different spinning conditions, varying the following spinning parameters: polymer concentration in the spinning solution, height of the air gap, and bore fluid composition. The effect of these parameters on the water permeability, the rejection of macromolecules (using dextrane with an average molecular weight of 68,800 g/mol), and the morphology of the membranes was studied. The results were also correlated to the viscosity of the spinning solution and to the ternary polymer/solvent/nonsolvent phase diagram. The morphology of the cross section and internal and external surfaces of the hollow fibers were analyzed using scanning electron microscopy (SEM). All membranes were shown to have a fingerlike void structure and a skin layer, depending on the spinning conditions, varying from (apparently) dense to porous. Pore size measurements by the bubble‐point method showed maximum pore sizes ranging from 0.3 to 2 μm. Permeability varied from 300 to 1000 L/(h−1 m−2 bar) and rejection to the dextrane from 10 to 78%. The viscosity of polymer solutions was in the range of 0.2 to 3.5 Pa s. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 841–853, 2004
One‐step synthesis and ring‐opening polymerization of novel macrocyclic(arylene multisulfide) oligomers
Authors: Chen K. , Meng Y. Z. , Tjong S. C. , Hay A. S.
Published: November 2003

A series of macrocyclic(arylene multisulfide) oligomers were synthesized under high dilution conditions by reacting diphenyl ether/diphenyl/diphenyl disulfide/diphenyl methane with dichloro disulfide in the presence of a trace amount of iron powder by a one‐step reaction. From MALDI‐TOF mass spectra, it was established that the repeating units of the cyclization ranged from two to seven and the unit of macrocyclic(arylene multisulfide) oligomers had one to seven sulfur atoms. The macrocyclic oligomers readily underwent ring‐opening polymerization in the melt, resulting in linear, high molecular weight polymultisulfides. DSC thermograms demonstrated that the four polymultisulfides, derived from the macrocyclic(arylene multisulfide) oligomers, are amorphous in nature. The macrocyclic(arylene multisulfide) oligomers and polymers were analyzed by MALDI‐TOF‐MS, IR, HPLC, NMR, DSC, and TGA methods. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 735–741, 2004
Packaging‐related properties of alkyd‐coated, wax‐coated, and buffered chitosan and whey protein films
Authors: Gällstedt M. , Hedenqvist M. S.
Published: November 2003

Packaging‐related properties of coated films of chitosan–acetic acid salt and whey protein concentrate (WPC) were studied. Chitosan (84.7% degree of deacetylation) and WPC (65–67% protein) were solution cast to films. These films are potential oxygen barriers for use in packaging. Coatings of wax or alkyds were used to enhance the water‐barrier properties. The packaging‐related properties of chitosan films treated in a buffering solution, with a pH of 7.8, were also investigated. The coated films were characterized with respect to Cobb absorbency, overall migration to water, water vapor transmission rate, and oxygen permeability. The creasability and bending toughness were determined. The wax was a more efficient barrier to liquid water and 90–95% relative humidity than the alkyd. However, the alkyd‐coated material had superior packaging‐converting properties. The alkyd‐coated WPC and chitosan–salt films were readily folded through 180° without any visible cracks or delamination. The overall migration from the alkyd‐coated materials was below the safety limit, provided the coat weight was higher than 7.5 mg/cm2 on WPC and 2.1 mg/cm2 on chitosan–salt. The barrier properties of chitosan film under moist conditions were improved by the buffer treatment. However, the buffering also resulted in shrinkage of the film. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 60–67, 2004
Influence of thermal treatments, molecular weight, and molecular weight distribution on the crystallization of β‐isotactic polypropylene
Authors: Marigo Antonio , Marega Carla , Causin Valerio , Ferrari Paolo
Published: November 2003

Six samples of isotactic polypropylene were examined to study the influence of the thermal treatments and the molecular weights and their distribution on the β‐crystallization of the polymer. The highest amount of the β‐phase was obtained by isothermal crystallization and in correspondence of high average molecular weights and wide molecular weight distributions. Small‐angle X‐ray scattering pointed out that a partial β‐crystallization seems not to influence the lamellar morphology parameters. Differential scanning calorimetry measurements, at different heating rates, allowed us to confirm that the multiple melting endotherms behavior of the β‐phase is to be correlated to a melting–recrystallization–melting mechanism. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 1008–1012, 2004
Effects of calcium ion on polyester‐type polyurethane emulsion and properties of polyurethane film
Authors: Lou Zhaowen , Luo Jun , Zhan Hongju
Published: November 2003

Polyurethane (PU) emulsions were prepared from polytetramethylene adipate diol, toluene diisocyanate, dimethanol propionic acid, and so forth. The effects of calcium ion on the stability of PU emulsion as well as on the water‐resistance property, tensile strength, and tensile yield of PU film were discussed. The results show that calcium ion can quickly damage the stability of PU emulsion. Meanwhile, calcium ion can distinctly counteract the unfavorable effects water has on the tensile properties of PU film. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 1285–1288, 2004