bluuebunny/crossref_metadata_2025_split huggingface dataset:
Experimental research of pool boiling heat transfer in horizontal narrow spaces
Authors: Long Enshen , Xin Mindao , Wang Yong 
Published: June 2004

AbstractMuch progress has been made in high‐performance electronic chips, the miniaturization of electronic circuits and other compact systems recently, which brings about a great demand for developing efficient heat removal techniques to accommodate these high heat fluxes. With this objective in mind, experiments were carried out on five kinds of test elements with distilled water and ethanol as working liquids. The test elements used in these experiments consisted of five parallel discs with diameters varying from 5 mm to 40 mm. The experiments were performed with the discs oriented horizontally and uniform heat fluxes applied at the bottom surfaces. The influence of narrow spacing, space size, working liquid property, and heat flux on boiling heat transfer performance in narrow spaces has been investigated. Experimental results showed that the boiling heat transfer coefficient of a narrow space was 3 to 6 times higher than that of pool boiling when the narrow space size and heat flux combine adequately, but the critical heat flux was lower than that of pool boiling. © 2004 Wiley Periodicals, Inc. Heat Trans Asian Res, 33(5): 307–315, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20017
Thermal radiation effects of a high‐temperature developing laminar flow in a tube
Authors: Xia Xin‐Lin , Ren De‐Peng , Tan He‐Ping 
Published: June 2004

AbstractThe thermal radiation effects of a high‐temperature developing laminar flow in a tube are investigated numerically. The two‐dimensional steady flow and heat transfer are considered for an absorbing‐emitting gray medium, whose density is dependent on the temperature. The governing equations of the coupled process are simultaneously solved by the discrete ordinate method combined with the control volume method. For a moderate optical thickness, the velocity distribution, the temperature distribution, and the radial heat flux distribution in the medium as well as the heat flux distribution on the tube wall are presented and discussed. The results show that the thermal radiation effects of a high‐temperature medium are significant under a moderate optical thickness. The flow and convective heat transfer are weakened, and the development of temperature distribution is accelerated noticeably. © 2004 Wiley Periodicals, Inc. Heat Trans Asian Res, 33(5): 299–306, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20018
Internal radiation effects in semitransparent high‐temperature coatings
Authors: Wang Ping‐Yang , Cheng Hui‐Er , Tan He‐Ping 
Published: June 2004

AbstractInternal thermal radiation in semitransparent coatings should be considered in the calculation of temperature and heat flux distribution in metal wall with a thermal barrier coating. In this paper, a ray tracing/node analysis method is used in the numerical simulation of a coupled transient radiative and conductive heat transfer in an absorbing‐scattering non‐gray coating. The present results show that the operating temperature is higher than the design temperature when the radiation is not considered. © 2004 Wiley Periodicals, Inc. Heat Trans Asian Res, 33(5): 271–278, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20021
Ultrastructural study of mineralization of a strontium‐containing hydroxyapatite (Sr‐HA) cement in vivo
Authors: Wong C. T. , Chen Q. Z. , Lu W. W. , Leong J. C. Y. , Chan W. K. , Cheung K. M. C. , Luk K. D. K. 
Published: June 2004

AbstractThe purpose of this study was to investigate the mineralization leading to osseointegration of strontium‐containing hydroxyapatite (Sr‐HA) bioactive bone cement injected into cancellous bone in vivo. Sr‐HA cement was injected into the ilium of rabbits for 1, 3, and 6 months. The bone mineralization area was found to be largest at 3 months, then at 1 month, and smallest at 6 months (p < 0.01) measured with tetracycline labeling. Osseointegration of Sr‐HA cement was achieved at 3 months as observed by scanning electron microscopy. A high calcium and phosphorus area was observed at the interface of bone–Sr‐HA cement determined by energy‐dispersive X‐ray analysis. Transmission electron microscopy gave evidence of the mechanism of bone formation. Dissolution of Sr‐HA into debris by the bone remodeling process was thought to increase the concentration of calcium and phosphorus at the interface of bone–Sr‐HA cement and stimulate bone formation. Crystalline Sr‐HA formed an amorphous layer and dissolved into the surrounding solution, then apatite crystallites were precipitated and formed new bone at 3 months. This young bone then becomes mature bone, which bonds tightly to the Sr‐HA cement with collagen fibers inserted perpendicularly after 6 months. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res 70A: 428–435, 2004
Lysophospholipids in development: Miles apart and edging in
Authors: Saba Julie D. 
Published: June 2004

AbstractSphingosine‐1‐phosphate (S1P) and lysophosphatidic acid (LPA) are endogenous bioactive lipids that participate in the regulation of mammalian cell proliferation, apoptosis, migration, and angiogenesis. These processes are each critical for successful embryogenesis, raising the possibility that lysophospholipid signaling may contribute to normal animal development. In fact, recent studies in developmental model systems have established that S1P and LPA are necessary for diverse developmental programs including those required for morphogenesis of vertebrate reproductive, cardiovascular and central and peripheral nervous systems (PNS), as well as the establishment of maternal‐fetal circulation and the immune system. Genetic, morphological, and biochemical characterization of developmental model systems offer powerful approaches to elucidating the molecular mechanisms of lysophospholipid signaling and its contributions to animal development and postnatal physiology. In this review, the routes of S1P and LPA metabolism and our current understanding of lysophospholipid‐mediated signal transduction in mammalian cells will be summarized. The evidence implicating lysophospholipid signaling in the development of specific vertebrate systems will then be reviewed, with an emphasis on signals mediated through G protein‐coupled receptors of the Edg family. Lastly, recent insights derived from the study of simple metazoan models and implications regarding lysophospholipid signaling in organisms in which Edg receptors are not conserved will be explored. © 2004 Wiley‐Liss, Inc.
Constructions of optimal optical orthogonal codes with weight five
Authors: Ma Shikui , Chang Yanxun 
Published: June 2004

AbstractSeveral direct constructions via skew starters and Weil's theorem on character sum estimates are given in this paper for optimal (gv, 5, 1) optical orthogonal codes (OOCs) where 60 ≤ g ≤ 180 satisfying g ≡ 0 (mod 20) and v is a product of primes greater than 5. These improve the known existence results on optimal OOCs. Especially, we provide an optimal (v, 5, 1)‐OOC for any integer v ≡ 60, 420, 660, 780, 1020, 1140, 1380, 1740 (mod 1800). © 2004 Wiley Periodicals, Inc. J Combin Designs 13: 54–69, 2005.
Characterization of rat liver microsomal metabolites of AM‐630, a potent cannabinoid receptor antagonist, by high‐performance liquid chromatography/electrospray ionization tandem mass spectrometry
Authors: Zhang Qiang , Ma Peng , Wang Weiqun , Cole Richard B. , Wang Guangdi 
Published: June 2004

AbstractThe in vitro metabolism of AM‐630 was studied by high‐performance liquid chromatography coupled with tandem mass spectrometry. AM‐630 is an aminoalkylindole analogue that behaves primarily as a potent CB2‐selective antagonist. In this study, 17 metabolic products were identified that resulted from the incubation of AM‐630 in rat liver microsome preparations. Six metabolic pathways were proposed to account for all detected metabolites: (1) o‐demethylation of the methoxyphenyl group, (2) morpholinyl ring opening, (3) hydroxylation on the methoxy/hydroxyl phenyl ring, (4) hydroxylation on the indole ring, (5) hydroxylation on the morpholine ring and (6) loss of the morpholine ring leading to metabolites containing either a hydroxylated or a carboxylated alkyl terminal. Three metabolites were identified as morpholinyl ring‐opening products: M1, M6 and M13. Six metabolites (M2–M5, M7 and M8) were proposed to be the products of o‐demethylation, hydroxylation on the methoxyphenyl group or the morpholinyl ring, dehydration following morpholinyl ring monohydroxylation, or a combination of the above metabolic pathways. The remaining eight metabolites were attributed to a pathway involving the loss of the morpholine ring at various points during the metabolic processes. Copyright © 2004 John Wiley & Sons, Ltd.
Lipase Catalyzed Copolymerization of 3(S)‐Isopropylmorpholine‐2,5‐dione and D,L‐Lactide
Authors: Feng Yakai , Klee Doris , Höcker Hartwig 
Published: June 2004

AbstractSummary: The polymerization and copolymerization of 3(S)‐isopropylmorpholine‐2,5‐dione (IPMD) and D,L‐lactide (DLLA) were carried out in the presence of Porcine pancreatic lipase type II (PPL) as a catalyst at 100 °C for 168 h. Homopolymers and random copolymers of various compositions were obtained with a carboxylic acid group at one end and a hydroxyl group at the other end. The glass transition temperature of the copolymers decreases with increasing mole fraction of DLLA residue in the copolymers.The copolymerization of 3(S)‐isopropylmorpholine‐2,5‐dione (IPMD) and D,L‐lactide (DLLA).magnified imageThe copolymerization of 3(S)‐isopropylmorpholine‐2,5‐dione (IPMD) and D,L‐lactide (DLLA).
Elastic Properties of Poly(hydroxybutyrate) Molecules
Authors: Špitalský Zdenko , Bleha Tomáš 
Published: June 2004

AbstractSummary: Elasticity of various poly(hydroxybutyrate) (PHB) molecules of regular and irregular conformational structure was examined by the molecular mechanics (MM) calculations. Force – distance functions and the Young's moduli E were computed by stretching of PHB molecules. Unwinding of the 21 helical conformation H is characterized at small deformations by the Young's modulus E = 1.8 GPa. The H form is transformed on stretching into the highly extended twisted form E, similar to the β‐structure observed earlier by X‐ray fiber diffraction. The computations revealed that in contrast to paraffins, the planar all‐trans structure of undeformed PHB is bent. Hence, a PHB molecule attains the maximum contour length in highly straightened, but slightly twisted conformations. A dependence of the single‐chain moduli of regular and disordered conformations on the chain extension ratio x was found. The computed data were used to analyze elastic response of tie (bridging) molecules in the interlamellar (IL) region of a semi‐crystalline PHB. A modification of the chain length distribution function of tie molecules τ(N) due to secondary crystallization of PHB was conjectured. The resulting narrow distribution τ(N) comprises the taut tie molecules of higher chain moduli prone to overstressing. The molecular model outlined is in line with the macroscopically observed increase in the modulus and brittleness of PHB with storage time.The force – length plots of deformation of the helical H form (○) and of the non‐planar Tn form (▪) of the PHB hexamer.magnified imageThe force – length plots of deformation of the helical H form (○) and of the non‐planar Tn form (▪) of the PHB hexamer.
PHEMA Hydrogels Obtained by a Novel Low‐Heat Curing Procedure with a Potential for In Situ Preparation
Authors: Ferruti Paolo , Grigolini Michela , Ranucci Elisabetta 
Published: June 2004

AbstractSummary: In this work, we report on poly(2‐hydroxyethyl methacrylate) (PHEMA) hydrogels obtained by a low heat curing reaction. These materials are suitable for in situ preparation and therefore endowed with a potential for several biomedical applications. The novel procedure adopted involves as the first step the synthesis of a soluble oligomeric PHEMA precursor containing polymerizable functions as side substituents. As the second step, the precursor is dissolved in equal amounts of 2‐hydroxyethyl methacrylate (HEMA) and water, to form a viscous but still injectable syrup. A low temperature water soluble initiator is then added. The curing reaction starts promptly and is completed within few minutes. During the entire process the internal temperature never rises above 40 °C. Preliminary mechanical characterizations performed on the hydrogels in their water‐swollen state and diffusion tests in absorption/desorption experiments clearly indicated that on all respects the novel hydrogels are comparable with conventional PHEMA hydrogels obtained according to literature from HEMA in the presence of divinyl crosslinkers. However, the much shorter curing time combined with the far lower curing temperature endow the new hydrogels with a higher potential in view of specific surgical requirements, and particularly for in situ preparation.Thermal profile of the curing reaction of different PHEMA hydrogel samples.magnified imageThermal profile of the curing reaction of different PHEMA hydrogel samples.
Temperature‐Sensitive Polyamidoamine Dendrimer/Poly(N‐isopropylacrylamide) Hydrogels with Improved Responsive Properties
Authors: Zhang Jian‐Tao , Huang Shi‐Wen , Zhuo Ren‐Xi 
Published: June 2004

AbstractSummary: Novel temperature‐sensitive poly(N‐isopropylacrylamide)/amine‐terminated polyamidoamine dendrimer G6‐NH2 hydrogels with fast responsive properties were synthesized by forming semi‐interpenetrating polymeric networks. In contrast to the conventional PNIPA hydrogel, these new gels showed rapid shrinking rate at the temperature above lower critical solution temperature (LCST), and exhibited higher equilibrium swelling ratio at room temperature. All these properties might be attributed to the incorporation of polyamidoamine dendrimer G6‐NH2, which forms water‐releasing channels and increases the hydrophilicity of PNIPA network. The novel hydrogels have potential applications in drug and gene delivery.Shrinking kinetics of homogeneous PNIPA hydrogel (H0) and novel PAMAM dendrimer G6‐NH2‐containing hydrogels (H10, H20 and H30).magnified imageShrinking kinetics of homogeneous PNIPA hydrogel (H0) and novel PAMAM dendrimer G6‐NH2‐containing hydrogels (H10, H20 and H30).
A New Technique for the Experimental Measurement of Monomer Partition Coefficients
Authors: Fortuny Montserrat , Graillat Christian , McKenna Timothy F. 
Published: June 2004

AbstractSummary: A new method for the measurement of monomer partitioning for emulsion polymerisation is presented. The method is based on measuring the partition coefficients for films cast from different latexes. Its validity was demonstrated for methyl methacrylate (MMA) and butyl acrylate (BA), as well as for mixtures of these two species, by comparing the data to model predictions using literature data. The model predictions and experimental results agreed quite well for MMA, but less so for BA due to its extremely low water solubility.
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Structure Property Correlation of Thermally Treated Hemp Fiber
Authors: Prasad Bhuwan M. , Sain Mohini M. , Roy Dibyendu N. 
Published: June 2004

AbstractSummary: Hemp (Cannabis sativa L.) is an important ligno‐cellulosic raw material for the manufacture of cost‐effective environmentally friendly composite materials. Hemp plant samples of different initial condition (stem and bast fibers) were subjected to heating varying the temperature (from 160 to 260 °C) and the ambient heating environment (air and inert atmosphere). Weight measurements showed that all heat treatment resulted in a reduced weight of hemp. Those treated in air showed drastic decline in weight compared with those treated under nitrogen, especially at a temperature higher than 220 °C. Observation using optical and scanning microscope showed the possibilities of opening up of the fiber bundles in both heating environments. However, higher temperature and presence of air had a more severe effect on fibers and associated tissues compared to effects under nitrogen. Heat treatment at 220 °C under nitrogen seemed to provide enough fiber opening without affecting tissues of the fibers.SEM micrograph of the cross‐section of hemp fiber heat treated in air environment.magnified imageSEM micrograph of the cross‐section of hemp fiber heat treated in air environment.
Synthesis and Characterization of Biodegradable Poly(ε‐caprolactone)‐Polyglycolide‐Poly(ethylene glycol) Monomethyl Ether Random Copolymer
Authors: Zhou Shaobing , Xu Jinggang , Yang Hua , Deng Xianmo 
Published: June 2004

AbstractSummary: Poly(ε‐caprolactone)‐polyglycolide‐poly(ethylene glycol) monomethyl ether random copolymers were synthesized from ε‐caprolactone (ε‐CL), glycolide (GA) and poly(ethylene glycol) monomethyl ether (MPEG) using stannous octoate as catalyst at 160 °C by bulk polymerization. The copolymers with different composition were synthesized by adjusting the weight ration of reaction mixture. The resultant copolymer with a weight ratio (10:15:75) of MPEG2000, GA, and CL was characterized by IR, 1H NMR, GPC and DSC. The new biodegradable copolymer has potential for medical applications since it is combined with properties of PCL, PGA and MPEG.
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Exertion of Inhibiting Effect by Aluminosilicate Layers on Swelling of Solution Blended EVA/Clay Nanocomposite
Authors: Pramanik Monoj , Acharya Himadri , Srivastava Suneel K. 
Published: June 2004

AbstractSummary: Ethylene vinyl acetate (EVA) copolymer/dodecyl ammonium ion intercalated montmorillonite (12Me‐MMT) nanocomposites were swelled in xylene under atmospheric condition. Swelling index of these nanocomposites decreased with filler loading indicating that the solvent uptake of these nanocomposites was inversely related to the filler contents. The volume fractions of nanocomposites showed an increasing trend with filler concentration because of unswelling effect exerted by aluminosilicate layers. The cross‐link density was determined using the Flory‐Rehner equation and it was observed that the cross‐link density of these nanocomposites also showed an increasing trend with increasing filler loading. Free energy change (ΔGmix) and the change in entropy (ΔSmix) on swelling of EVA/12Me‐MMT nanocomposites in xylene were calculated and these values reaffirmed that the interaction between polymer chains and silicate layers was very strong which induced remarkable inhibiting ability on EVA matrix when swelled in xylene.TEM photograph of EVA/12Me‐MMT nanocomposite containing 8 wt.‐% 12Me‐MMT.magnified imageTEM photograph of EVA/12Me‐MMT nanocomposite containing 8 wt.‐% 12Me‐MMT.
Trust and relationship commitment in the United Kingdom voluntary sector: Determinants of donor behavior
Authors: Sargeant Adrian , Lee Stephen 
Published: June 2004

AbstractThis article explores the relationship between trust, relationship commitment, and giving behavior. It operationalizes trust and commitment, develops measurement scales for each construct, and uses the technique of structural equation modeling to determine whether trust impacts directly on giving behavior or whether its effects are mediated by commitment. It concludes that commitment plays a mediating role and discusses implications for professional fund‐raising practice. © 2004 Wiley Periodicals, Inc.
Unfolding consumer impulsivity: An existential–phenomenological study of consumers with attention deficit disorder
Authors: Kaufman‐Scarborough Carol , Cohen Judy 
Published: June 2004

AbstractThis article attempts to unfold consumer impulsivity by gathering in‐depth stories from persons whose impulsivity is a lifetime trait because of their attention deficit disorder (ADD/ADHD). The manuscript provides overviews of impulsivity, ADD, and impulsive consumer behavior. Insights into possible consumer‐behavior challenges are offered from an information‐processing perspective. Through thematic analysis of the respondents' lifetime stories, this study helps illuminate the black box of the consumer's mind with respect to impulsive consumption, by relating impulsive consumer behavior to specific problems in information processing. As such, it not only contributes to understanding of the consumer behavior of those with ADD, but also presents a kinder and gentler picture of consumers who are dealing with information overload and frustration, rather than what might be a more common stereotype of consumers who are simply out of control. © 2004 Wiley Periodicals, Inc.
Consumer knowledge of the world wide web: Conceptualization and measurement
Authors: Page Kelly , Uncles Mark 
Published: June 2004

AbstractUser‐directed technologies such as the Web are becoming more prevalent. To understand the usage of these technologies the characteristics of users need to be studied. The focus here is on one user characteristic: consumer knowledge content. Based on qualitative and quantitative analyses, four scales are developed to measure common declarative, common procedural, specialized declarative, and specialized procedural knowledge content of the Web. In addition, an illustration is provided to show how these scales might be used for segmenting consumers. The procedures used may be of value in a wide range of studies where the focus is on investigating users of user‐directed electronic technologies. © 2004 Wiley Periodicals, Inc.
Biology and chemistry of the inhibition of nitric oxide synthases by pteridine‐derivatives as therapeutic agents
Authors: Matter Hans , Kotsonis Peter 
Published: June 2004

AbstractInhibitors of the family of nitric oxide synthases (NOS‐I–III; EC 1.14.13.39) are of interest as pharmacological agents to modulate pathologically high nitric oxide (NO) levels in inflammation, sepsis, and stroke. In this article, we discuss the approach for targeting the unique (6R)‐5,6,7,8‐tetrahydro‐l‐biopterin (H4Bip) binding site of NOS by appropriate inhibitors. This binding site maximally increases enzyme activity and NO production from the substrate l‐arginine upon cofactor binding. The first generation of H4Bip‐based NOS inhibitors was based on 4‐amino H4Bip derivatives in analogy to anti‐folates such as methotrexate. In addition, we discuss the structure–activity relationship of a related series of 4‐oxo‐pteridine derivatives. Furthermore, molecular modeling studies provide an understanding of pterin antagonism on a structural level based on favorable and unfavorable interactions between protein binding site and ligands. These techniques include 3D‐QSAR (CoMFA, CoMSIA) to understand ligand affinity and GRID/consensus principal component analysis (CPCA) to learn about selectivity requirements. Collectively these approaches, in combination with the presented SAR and structural data, provide useful information for the design of novel NOS inhibitors with increased isoform selectivity. © 2004 Wiley Periodicals, Inc. Med Res Rev, 24, No. 5, 662–684, 2004
A quasi‐static boundary value problem in multi‐surface elastoplasticity: Part 1—Analysis
Authors: Brokate Martin , Carstensen Carsten , Valdman Jan 
Published: June 2004

AbstractThe quasi‐static evolution of an elastoplastic body with a multi‐surface constitutive law of linear kinematic hardening type allows the modelling of curved stress–strain relations. It generalizes classical small‐strain elastoplasticity from one to various plastic phases. This paper presents the mathematical models and proves existence and uniqueness of the solution of the corresponding initial‐boundary value problem. The analysis involves an explicit estimate for the effective ellipticity constant. Copyright © 2004 John Wiley & Sons, Ltd.