bluuebunny/crossref_metadata_2025_split huggingface dataset:
Vorhersage und Analyse natürlicher Lüftungsvorgänge
Authors: Gritzki Ralf , Rösler Markus , Richter Wolfgang 
Published: February 2007

AbstractDie rechnerische Vorhersage natürlicher Lüftungsvorgänge in Gebäuden gestaltet sich aufgrund der Problematik der Randbedingungen und der instationären Natur des Vorganges oft schwierig. Hinzu kommt, daß der reine Lüftungsvorgang lediglich eine Teil information liefert, wenn beispielsweise Nachtlüftungen und die damit einhergehende Entwärmung untersucht werden müssen. Unter Nutzung der Möglichkeiten einer speziellen Finite‐Elemente‐Methode (FEM) lassen sich Randbedingungsformulierungen finden, die für die Berechnung natürlicher Lüftungsvorgänge geeignet sind. Weiterhin werden Möglichkeiten und Kriterien vorgestellt, instationäre Lüftungsvorgänge unter hygienischen und energetischen Gesichtspunkten zu analysieren. Der energetische Aspekt lässt sich besonders herausarbeiten, wenn man Raumluftströmungsberechnung und thermische Gebäudesimulation geeignet kombiniert.
Ein Modell zur hygrisch‐thermischen Gebäudesimulation mit Hilfe der Kopplung von Zonen‐ und Feldmodell
Authors: Perschk Alf , Meinhold Uwe 
Published: February 2007

AbstractEs wird ein Modell vorgestellt, das eine erweiterte Analyse der hygrisch‐thermischen Zustandsgrößen eines Gebäudes, durch die direkte Kopplung von Zonen‐ mit Feldmodellen, ermöglicht. Das ursprünglich auf die Berechnung von technischen Anlagen ausgerichtete Programmpaket TRNSYS ist so aufgebaut, daß in das gegebene Bilanzierungsgebiet eigene Algorithmen für unterschiedliche technische Komponenten oder physikalische Zusammenhänge integriert werden können. Das Gesamtsystem aus vorhandenen Algorithmen und neuen Komponenten wird von TRNSYS für jeden Zeitschritt neu gelöst. Es besteht damit die Möglichkeit, Feldmodelle zur detaillierten Beschreibung der physikalischen Zustände in der Raumumschließungskonstruktion (Wand) oder die komplexe Analyse der Raumluftströmung mit dem Zonenmodell für die Gebäudesimulation zu verbinden. Die neu in das TRNSYS‐Gerüst integrierten Module und die Wechselwirkung mit dem vorhandenen Zonenmodell (Standard TYPE 56) werden erläutert. Eine Basis, die entwickelten Simulationstools zu testen und zu validieren, bietet die Mitarbeit im Rahmen der IEA Annex 41 “Whole building heat, air and moisture response (MOIST‐ENG)”. Einzelne Validierungsberechnungen und praktische Anwendungsbeispiele werden vorgestellt.
Two case studies on user interactions with buildings' environmental systems
Authors: Mahdavi Ardeshir , Lambeva Lyudmila , Mohammadi Abdolazim , Kabir Elham , Pröglhöf Claus 
Published: February 2007

AbstractThe design and operation of energy‐efficient systems for indoor environment control (heating, cooling, ventilation, lighting) can benefit from reliable information on occupants' actions to bring about changes in the status of building control systems. Specifically, the computational modeling of occupants' control‐oriented actions in building performance simulation applications can be significantly improved based on such empirical information on user behavior. The present paper concerns the type and number of user control actions as related to building systems in two office buildings in Vienna, Austria.
Bestimmung des thermischen und hygrischen Zustands der Raumluft bei freier Konvektion
Authors: Göbelsmann Marc 
Published: February 2007

AbstractDie Kenntnis des zu erwartenden thermischen und hygrischen Zustands der Raumluft bereits in der Planungsphase eines Gebäudes ist in vielerlei Hinsicht bedeutsam. Insbesondere in hohen Räumen bildet sich vielfach ein vertikaler Gradient der Temperatur und der Feuchte im Raum aus. Der Einfluß der freien Konvektion darf bei der Berechnung nicht vernachlässigt werden. Hierfür sind geeignete Rechenmodelle erforderlich. Es wurden ein Feldmodell und ein Multi‐Zonen‐Modell entwickelt und anhand von Meßdaten validiert. Die Berechnung mit dem Feldmodell liefert detaillierte Informationen über den Zustand der Raumluft für jeden Ort im Raum; der numerische Aufwand ist allerdings sehr groß. Mittels des Multi‐Zonen‐Modells kann der Zustand der Raumluft für einzelne Bereiche im Raum unter prinzipieller Berücksichtigung der freien Konvektion berechnet werden; der erforderliche numerische Aufwand ist dabei gering. Beide Modelle ergänzen sich einander und bieten die Möglichkeit, den Aufwand der Berechnung an die jeweilige Problemstellung anzupassen.
An aerobic sequencing batch reactor for 2,4,6‐trinitrophenol (picric acid) biodegradation
Authors: Weidhaas Jennifer L. , Schroeder Edward D. , Chang Daniel P.Y. 
Published: February 2007

AbstractA bench scale sequencing batch reactor (SBR) was designed and tested for degradation of 2,4,6‐trinitrophenol (TNP) or picric acid‐contaminated wastewater or groundwater. Under varying temperatures (25, 15 and 10°C) and influent concentrations (40–200 mg/L TNP) a stable biomass was developed that was consistently capable of degrading the explosive compound to below regulatory drinking water limits (0.057 mg/L). The reactor was initially seeded with a nitroaromatic and nitramine degrading isolate Rhodococcus opacus strain JW01. Kinetic growth modeling was conducted revealing µmax values at 25, 15 and 10°C of 0.14, 0.08 and 0.04 d−1, while the modeled Ks values were 0.68, 1.11 and 1.24 mg/L, respectively. Overall TNP removal efficiency in the SBR was on average > 99.9% over the 2000 hours of operation. Removal of TNP to below drinking water standards, with low residual dissolved carbon and significant release of nitrogen from the parent compound was accomplished. Biotechnol. Bioneg. 2007;97: 1408–1414. © 2007 Wiley Periodicals, Inc.
Anaerobic methanethiol degradation in upflow anaerobic sludge bed reactors at high salinity (≥0.5 M Na+)
Authors: van Leerdam Robin C. , de Bok Frank A.M. , Lens Piet N.L. , Stams Alfons J.M. , Janssen Albert J.H. 
Published: February 2007

AbstractThe feasibility of anaerobic methanethiol (MT) degradation at elevated sodium concentrations was investigated in a mesophilic (30°C) lab‐scale upflow anaerobic sludge bed (UASB) reactor, inoculated with estuarine sediment originating from the Wadden Sea (The Netherlands). MT was almost completely degraded (>95%) to sulfide, methane and carbon dioxide at volumetric loading rates up to 37 mmol MT·L−1·day−1, 0.5 M sodium (NaCl or NaHCO3) and between pH 7.3 and 8.4. Batch experiments revealed that inhibition of MT degradation started at sodium (both NaCl and NaHCO3) concentrations exceeding 0.8 M. Sulfide inhibited MT degradation already around 3 mM (pH 8.3). Biotechnol. Bioeng. 2007; 98: 91–100. © 2007 Wiley Periodicals, Inc.
Transseptal puncture: Use of an angioplasty guidewire for enhanced safety
Authors: Hildick‐Smith David , McCready James , de Giovanni Jo 
Published: February 2007

AbstractDuring transseptal puncture, once the needle tip has successfully accessed the left atrium, advancement of the needle, dilator and sheath into the left atrium can risk left atrial free wall perforation, particularly if the interatrial septum is aneurysmal and tents far into the left atrial cavity during puncture. We have modified our transseptal technique such that once the left atrium is accessed with the needle tip, a 0.014″ angioplasty guidewire is advanced down the Brockenbrough needle. This is guided into the left upper pulmonary vein, and the needle, dilator and sheath advanced over this wire towards the left upper pulmonary vein. In this way, the risk of perforation of the left atrial free wall is negated. We have since used this technique in 30 cases without difficulties. © 2007 Wiley‐Liss, Inc.
Lewis Base‐Catalyzed Formation of α ‐Trifluoromethyl Alcohol from CF3SiMe3 and Carbonyl‐Containing Compounds
Authors: Zhu Shi‐Fa , Pang Wan , Xing Chun‐Hui , Zhu Shi‐Zheng 
Published: February 2007

AbstractLewis base could catalyze the formation of α‐trifluoromethyl alcohol from CF3SiMe3 and carbonyl‐containing compounds. It was found that the α‐trifluoromethyl alcohol could also be used to promote the synthesis in basic conditions.
Gradient coil with active endcap shielding
Authors: Baig Tanvir N. , Eagan Timothy P. , Petropoulos Labros S. , Kidane T.K. , Edelstein William A. , Brown Robert W. 
Published: February 2007

AbstractShielded gradient coil assemblies produce eddy currents in surrounding metal structures. Such eddy currents can degrade image quality and produce acoustic noise. These effects are magnified for high‐field MRI scanners because of increased Lorentz forces. Conventional actively shielded gradient assemblies consist of primary and secondary coils in the shape of cylindrical shells surrounding the imaging volume. One of the principal regions of field leakage is at the ends of the gradient structure, and these fields are responsible for substantial eddy current generation. We present here a new shielded gradient coil design with an endcap current distribution having both azimuthal and radial components. Our active endcap design significantly reduces the fringe field at the cryostat inner bore. A peak fringe field reduction near the end of the gradient coil of 42% is obtained for the Z gradient relative to a traditional design without active endcaps. The reduction of peak fringe field near the end of the coil for transverse gradients (X and Y) is approximately 40%. We discuss the degree to which the suppression of peak fringe fields corresponds to a reduction in the acoustic noise generated near the end of the warm bore. © 2007 Wiley Periodicals, Inc. Concepts Magn Reson Part B (Magn Reson Engineering) 31B: 12–23, 2007
The Sediments and Benthic‐Pelagic Exchange in the Shallow Lake Müggelsee (Berlin, Germany)
Authors: Kozerski Hans‐Peter , Kleeberg Andreas 
Published: February 2007

AbstractThe sediments and exchange processes of the shallow (mean depth 4.9 m), polymictic, eutrophic Müggelsee have been studied over more than 30 years. Here, previous results are summarised and completed by new data. Sediment analyses were used to identify changes in loadings and migration processes within the sediments of the 12000 year old lake. The surficial oligohumic sediments are rich in Fe (8.8 ± 1.9% DW) and in P (2.7 ± 0.5 mg P g−1 DW). Mass balances of P and Fe as well as sediment trap measurements and sinking velocity analyses showed that the retention of matter strongly varies within seasons and years. The lake amplifies the seasonal fluctuations of P in the River Spree system by a strong redox‐controlled, benthic P‐release in summer. Since 1988, P‐release has exceeded retention so that the lake changed from a P‐sink to a source. The retention rate dropped in summer to ‐7.3 mg P m−2 d−1 and in winter to 1.4 mg P m−2 d−1.
Annual Changes of Abundance and Biomass of Planktonic Ciliates in the Gdańsk Basin, Southern Baltic
Authors: Witek Marzena 
Published: February 2007

AbstractSeasonal changes in the species composition, abundance and biomass of planktonic ciliates were determined every 2–3 weeks at two sites of 30 m depth and one location of 105 m depth in the southwestern Gdańsk Basin between January 1987 and January 1988. A total of 40 ciliate taxa were observed during this period. Autotrophic Mesodinium rubrum dominated ciliate abundance and biomass: maximal values of 50 · 10−1 ind. 1‐1 and 65 μg C 1−1 were recorded. The annual mean biomass of M. rubrum comprised 6 to 9% of the annual mean phytoplankton biomass. The highest abundances and biomasses of heterotrophic ciliates were noted at all stations in the spring and summer in the euphotic zone with maximum values of 28 · 103 ind. 1−1 and 23 μg C 1−1. Three ciliates assemblages were distinguished in the epipelagic layer: large and medium‐size non‐predatory ciliates, achieving peak abundance in spring and autumn; small‐size microphagous ciliates and epibiotic ciliates which were abundant in summer, and large‐size predacious ciliates dominating in spring. Below 60 m, a separate deep‐water ciliate community composed of Prorodon‐like ciliates and Metacystis spp. was found. The ciliate biomass in the 60–105 m layer was similar to the ciliate biomass in the euphotic zone. The heterotrophic ciliate community contributed 10 to 13% to the annual mean zooplankton biomass. The potential annual production of M. rubrum comprised 6 to 9% of the total primary production. Carbon demand of non‐predatory ciliates, calculated on the basis of their potential production, was estimated to be equivalent to 12–15% of the gross primary production.
Rotifera Recorded from China, 1893–1997, with Remarks on Their Composition and Distribution
Authors: Zhuge Yan , Huang Xiangfei , Koste Walter 
Published: February 2007

AbstractA search of the literature on rotifers recorded from China, includes today 477 valid species names and 42 subspecies or infrasubspecific variants in 84 genera and 28 families recorded since 1893. Chinese rotifera research is reviewed, and all recorded species are listed with current taxonomic status and their first localities in China. Most of the named taxa are widely distributed or cosmopolitan, with only a small number (about 3%) possibly restricted to China. This fauna exhibits 15 endemic taxa. The composition and distribution of Chinese Rotifera are briefly analyzed. It is likely that considerably more rotifers remain to be described from China as further study to be carried on and taxonomic resolution improves.
Suppression of growth and cancer‐induced angiogenesis of aggressive human breast cancer cells (MDA‐MB‐231) on the chorioallantoic membrane of developing chicken embryos by E‐peptide of pro‐IGF‐I
Authors: Chen Maria J. , Peter Chiou Pinwen , Lin Patrick , Lin Chun‐Mean , Siri S. , Peck Konan , Chen Thomas T. 
Published: February 2007

AbstractE‐peptide of the pro‐Insulin‐like growth factor‐I (pro‐IGF‐I) is produced from pre‐pro‐IGF‐I by proteolytic cleavage in the post‐translational processing. Previous in vitro studies conducted in our laboratory showed that Ea4‐peptide of rainbow trout (rt) pro‐IGF‐I or Eb‐peptide of human (h) pro‐IGF‐I exhibited activities including induction of morphological differentiation, inhibition of anchorage‐independent cell growth and suppression of invasion of several well established human cancer cell lines such as MDA‐MB‐231, HT‐29, SK‐N‐F1, and HepG‐2 (Chen et al. [2002] Gen Comp Endocrinol 126:342–351; Kuo and Chen [2002] Exp Cell Res 280:75–89). Seeding of aggressive human breast cancer cells, MDA‐MB‐231, on the chorioallantoic membrane (CAM) of 5 days old chicken embryos resulted in rapid growth and invasion of the cells and induction of blood vessel formation around the MDA‐MB‐231 cell mass in the chicken embryos. The invasion of MDA‐MB‐231 cells in the chicken embryos was further confirmed by immunocytochemistry. The rapid growth and invasion of MDA‐MB‐231 cells and the induction of blood vessel formation by MDA‐MB‐231 cells on chicken CAM are inhibited by treatment with a single or multiple doses of rtEa4‐ or hEb‐peptide. Furthermore, a dose‐dependent inhibition of angiogenesis by rtEa4‐ or hEb‐peptide was also demonstrated by the chicken CAM assay. Results of microarray analysis of human gene chips (containing 9,500 unique cDNA clones) and confirmation by comparative real‐time RT‐PCR analysis showed that a group of genes related to cancer cell activities are up‐ or down‐regulated in MDA‐MB‐231 cells transfected with a rtEa4‐peptide gene. Together these results confirm the anti‐tumor activity of rtEa4‐ and hEb‐peptides, and further suggest that these peptides could be developed as therapeutics for treating human cancers. J. Cell. Biochem. 101:1316–1327, 2007. © 2007 Wiley‐Liss, Inc.
Dissociation of growth arrest and CYP24 induction by VDR ligands in mammary tumor cells
Authors: Valrance Meggan E. , Brunet Andrea H. , Acosta Anna , Welsh JoEllen 
Published: February 2007

AbstractMurine mammary tumor cells with differential vitamin D receptor (VDR) expression were used to study the mechanisms of growth inhibition by vitamin D steroids. In VDR‐expressing WT145 cells, 1,25D and its synthetic analog EB1089 induce growth arrest and transcriptionally upregulate the well‐characterized VDR target gene CYP24. 1,25D also induces apoptosis in WT145 cells through activation of initiator and executioner caspases and the calcium‐dependent protease calpain. We also demonstrate that WT145 cells express CYP27B1, the enzyme that converts 25‐hydroxyvitamin D3 (25D) to 1,25D, and that 25D inhibits growth of these cells but does not trigger apoptosis or induce CYP24 expression. Comparative studies were conducted in KO240 cells, which were derived from VDR knockout mice and found to retain expression of CYP27B1. KO240 cells were not growth inhibited nor rendered apoptotic by any of the tested vitamin D compounds. These data conclusively demonstrate that VDR mediates the anti‐proliferative and pro‐apoptotic effects of vitamin D metabolites and analogs, but that the potency of a vitamin D compound to induce the VDR target gene CYP24 does not accurately predict its potency in mediating growth regulation. J. Cell. Biochem. 101: 1505–1519, 2007. © 2007 Wiley‐Liss, Inc.
Supracolloidal Structures through Liquid‐Liquid Interface Driven Assembly and Polymerization
Authors: Colver Patrick J. , Chen Tao , Bon Stefan A. F. 
Published: February 2007

AbstractSolid particles can adhere to liquid‐liquid interfaces. When emulsion droplets are stabilized in such a way one speaks of a Pickering emulsion. The supracolloidal structures formed by this interface driven assembly process can be referred to as colloidosomes. Herein we explain the concept of colloidosome formation, their deformation behavior upon evaporation of their inner phase. Moreover, we describe Pickering miniemulsion and suspension polymerization processes, both yielding armored raspberry‐type core‐shell composite polymer particles.
Poly(styrene‐co‐butyl acrylate)‐Brazilian Montmorillonite Nanocomposites, Synthesis of Hybrid Latexes via Miniemulsion Polymerization
Authors: Moraes Raul P. , Santos Amilton M. , Oliveira Pedro C. , Souza Fátima C. T. , do Amaral Marcelo , Valera Ticiane S. , Demarquette Nicole R. 
Published: February 2007

AbstractIn this work hybrid latexes of poly(styrene‐co‐butyl acrylate)/montmorillonite were synthesized via miniemulsion polymerization using a Brazilian organically modified montmorillonite. The natural clay was previously treated with Cetyltrimethyl ammonium chloride (CTAC) in order to increase the interaction between the clay and the monomer phase. Three different methodologies to modify the clay and their influence on the final properties of the composites obtained were evaluated in this work. The modified clays were characterized by X‐ray diffraction (XRD). The films obtained after drying the latexes were characterized by dynamic‐mechanical thermal analyses (DMTA), small amplitude oscillatory shear (SAOS), transmission electronic microscopy (TEM) and Cobb test. The X‐ray diffractograms, showed an increase of basal spacing after organic treatment indicating the introduction of CTA+ within the clay interlamelar space. This interlamelar space was further increased after polymerization for all of the three differently modified clays studied, indicating that in situ polymerization occurred. The introduction of organically modified clays did not influence the kinetics of polymerization. Stable latexes were obtained. The DMTA presented improved mechanical properties for the materials charged with two of the modified clays studied when compared to a conventional composite. SAOS analysis revealed that an exfoliated structure might have been obtained when adding one of the modified clays to the reacting medium. Cobb tests showed that the permeability to water was reduced by the incorporation of clays to the copolymer.
Study on Element Migration from Plastic Food Packagings to Simulating Solutions
Authors: Soares Eufemia Paez , Saiki Mitiko 
Published: February 2007

AbstractIn the present study a radiometric method was established for element migration determination from plastic food packagings to simulating solutions of 3% acetic acid solution and of water. This radiometric method consisted in irradiating plastics with neutrons, followed by exposition for migration and measurement the radioactivity in food‐simulating solution. The experimental conditions used were 10 days of exposure at 40 °C. The migration was studied for packagings of water and dairy products. The results indicated the migration of Co, Cr and Sb to the simulating solutions. The advantages of this methodology are no necessity of blank analysis, as well as the use of high purity simulants. Moreover, it is possible to evaluate the migration to the food contents, instead of simulants. The detection limits of migration indicated the high sensitivity of the radiometric method.
Three‐Dimensional Observations of Grain Boundary Morphologies in a Cylinder‐Forming Block Copolymer
Authors: Jinnai Hiroshi , Yasuda Kaoru , Nishi Toshio 
Published: February 2007

AbstractThe grain boundary morphology of a cylinder‐forming poly(styreneblock‐isoprene) (SI) diblock copolymer was investigated using transmission electron microtomography (TEMT). The three‐dimensional (3D) morphologies of the grain boundaries between the two grains with different orientation angle, α, were investigated. In the present study, two kinds of grain boundary morphologies, α ≃ 90° and α ≃ 120°, were examined in 3D. It was found that, in the case of α ≃ 90°, most of the cylindrical domains bent at the grain boundary in order not to intersect each other, while the cylindrical domains were found to be smoothly connected and were continuous in the case of α ≃ 120°. The observed morphologies indicated that the chain conformation inside the cylindrical microdomains plays more significant role than the segmental interaction between the two blocks.
Production of a Clay‐Polymer Composite Aiming the Removal of Residual Sodium from Biodiesel
Authors: Lopes Toni Jefferson , Gonçalves Odinei Hess , Quadri Mara Gabriela Novy , Machado Ricardo Antonio Francisco , Quadri Marintho Bastos 
Published: February 2007

AbstractClay particles are frequently used in adsorption processes with aqueous solution, but the formed colloidal dispersion is responsible for several phenomena that hinder the flow. To overcome these problems, this work deals with adsorption experiments carried out using an adsorptive media prepared with clay immobilized on the surface of polymer pellets. The effect of biodiesel on three polymer pellets and on a clay‐polymer composite was evaluated. Only the composite was not affected by the biodiesel, and its optimal operational conditions were determined. The composite was effective to remove residual sodium from biodiesel, attaining levels below law requirements.
Morphological Parameters of PP/PA6 Blend Measured In‐Line During Extrusion
Authors: Pinheiro Luís Antonio , Bitencourt Celina Souza , Pessan Luiz Antonio , Canevarolo Sebastião Vicente 
Published: February 2007

AbstractAn optical detector, assembled at a slit die at the exit of a twin screw extruder was used to quantify in‐line the extrusion of a PP/PA6 immiscible blend. During the extrusion the detector respond according to the changes in concentration and particle size of the polyamide 6 phase. The influence of dispersed phase concentration was evaluated varying its concentration from 0 to 5% (w/w). Reduction in the PA6 particle size was followed adding different amounts of polypropylene grafted with acrylic acid (PP‐g‐AA), which acts as a compatibilizer. The normalized detector signal intensity increases with an increase in PA6 concentration, due to an increase in the number of scattering particles in the medium, and with a decrease in its particle size. Plots of detector signal as a function of particle concentration and size enabled the calculation of the extinction cross sections of the PA6 segregated particles.