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81.
This paper describes a performance analysis of two open-cycle absorption systems for solar cooling. The working fluid is LiCl---H2O, where the water desorbs into the atmosphere and is replaceable. Both systems comprise a closed absorber and evaporator as in conventional, single-stage absorption chillers. The open part of the cycle is in the regenerator, used to reconcentrate the absorbent solution by means of solar energy. One of the systems under study has employed direct regeneration in a regenerating collector, exposing the solution simultaneously to the sun and to a stream of air. The other has employed indirect regeneration by contacting the solution with air heated elsewhere in a flat-plate collector. The analysis was performed using a code developed for modular simulation of absorption systems under varying cycle configurations and with different working fluids. The code has been modified to accommodate the features of the open-cycle systems, including the regenerating collector and the air-solution contactor. Based on specified design features, the code calculates the operating parameters in each system for a variety of conditions. The paper presents the performance curves obtained for both systems. Results indicate a definite performance advantage of the direct-regeneration system over the indirect-regeneration one. 相似文献
82.
Programmers today face a bewildering array of parallel programming models and tools, making it difficult to choose an appropriate one for each application. An increasingly popular programming model supporting structured parallel programming patterns in a portable and composable manner is the task‐centric programming model. In this study, we compare several popular task‐centric programming frameworks, including Cilk Plus, Threading Building Blocks, and various implementations of OpenMP 3.0. We have analyzed their performance on the Barcelona OpenMP Tasking Suite benchmark suite both on a 48‐core AMD Opteron 6172 server and a 64‐core TILEPro64 embedded many‐core processor. Our results show that the OpenMP offers the highest flexibility for programmers, and this flexibility comes to a cost. Frameworks supporting only a specific and more restrictive model, such as Cilk Plus and Threading Building Blocks, are generally more efficient both in terms of performance and energy consumption. However, Intel's implementation of OpenMP tasks performs the best and closest to the specialized run‐time systems. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
83.
Leveraging the Ambipolar Transport in Polymeric Field‐Effect Transistors via Blending with Liquid‐Phase Exfoliated Graphene 下载免费PDF全文
84.
Maria?Elena?LeyvaEmail author Filiberto?González?Garcia Alvaro?Antonio?Alencar?de?Queiroz Demétrio?Artur?Werner?Soares 《Journal of Materials Science: Materials in Electronics》2011,22(4):376-383
The metallopolymer polyaniline-silver (PANI-Ag) was synthesized and used as conductive filler in crosslinked diglycidyl ether
of bisphenol A (DGEBA) epoxy network. The hybrid organic/inorganic PANI-Ag powders were successfully synthesized via in situ
chemical oxidation of polyaniline-emeraldine base (PANI-EB) by the capped Ag+ on the polyaniline-emeraldine base (PANI-EB) surface. The UV–Vis and FT-IR spectra confirmed the pernigraniline structure
(PN) of PANI in the hybrid PANI-Ag. The PANI-Ag dispersion in epoxidic matrix was analyzed by optical microscopy (OM). The
images analysis from OM showed that the particle agglomerate size of the metallopolymer increased with increasing PANI-Ag
concentration in the DGEBA composite, owing to the aggregation effect. The dc conductivity and impedance spectroscopy of the
DGEBA/PANI-Ag composite was measured at different PANI-Ag concentrations in the DGEBA network. The electrical dc conductivity
of the PANI-Ag was 35.1 S cm−1 and was dependent of the PANI-Ag concentration in DGEBA matrix. The real and imaginary part of impedance complex measurements
indicates a strong interfacial polarization at low frequency for both PANI-Ag and DGEBA/PANI-Ag, respectively. The imaginary
part of impedance complex Im(Z) data decrease with the PANI-Ag hybrid concentration in the frequencies range of 102–106 Hz. The dependence of the Im(Z) on the frequency exhibited a relaxation process in both, PANI-Ag and DGEBA/PANI-Ag composite with 10 phr of PANI-Ag powder. 相似文献
85.
Dawid Ponka Marta D. Winiewska Manuel D. Peris-Díaz Artur Krel Arkadiusz M. Bonna Wojciech Bal 《International journal of molecular sciences》2022,23(24)
Hepcidin (DTHFPICIFCCGCCHRSKCGMCCKT), an iron-regulatory hormone, is a 25-amino-acid peptide with four intramolecular disulfide bonds circulating in blood. Its hormonal activity is indirect and consists of marking ferroportin-1 (an iron exporter) for degradation. Hepcidin biosynthesis involves the N-terminally extended precursors prepro-hepcidin and pro-hepcidin, processed by peptidases to the final 25-peptide form. A sequence-specific formation of disulfide bonds and export of the oxidized peptide to the bloodstream follows. In this study we considered the fact that prior to export, reduced hepcidin may function as an octathiol ligand bearing some resemblance to the N-terminal part of the α-domain of metallothioneins. Consequently, we studied its ability to bind Zn(II) and Cd(II) ions using the original peptide and a model for prohepcidin extended N-terminally with a stretch of five arginine residues (5R-hepcidin). We found that both form equivalent mononuclear complexes with two Zn(II) or Cd(II) ions saturating all eight Cys residues. The average affinity at pH 7.4, determined from pH-metric spectroscopic titrations, is 1010.1 M−1 for Zn(II) ions; Cd(II) ions bind with affinities of 1015.2 M−1 and 1014.1 M−1. Using mass spectrometry and 5R-hepcidin we demonstrated that hepcidin can compete for Cd(II) ions with metallothionein-2, a cellular cadmium target. This study enabled us to conclude that hepcidin binds Zn(II) and Cd(II) sufficiently strongly to participate in zinc physiology and cadmium toxicity under intracellular conditions. 相似文献
86.
Artur Scheib 《Electrical Engineering (Archiv fur Elektrotechnik)》1939,33(2):71-99
Zusammenfassung Die Darstellung des Kurzschlusses erfolgte durch Überlagerung der Spannung am Kurzschlußort mit einer Überlagerungsspannung, die ihrerseits wieder in einheitlicher, für die Zeiten vor und nach dem Kurzschlußeintritt geltender Form durch ein Fourier-Integral dargestellt wurde. Aus diesem Überlagerungsspannungsintegral wurden die Überlagerungsstromintegrale abgeleitet unter Verwendung der Stromgleichungen für die einzelnen Teile der untersuchten Anordnungen bzw. der entsprechenden Ersatzwiderstände, deren Aufbau aus den Ersatzwiderständen der Schaltelemente der Anordnungen in allgemeiner Form behandelt wurde. Die Auswertung der Stromintegrale wurde sodann ebenfalls in allgemeiner Form vorgenommen, wobei ein Näherungsverfahren zu grundsätzlicher Anwendung kam, das eine erhebliche Vereinfachung der Rechnung mit sich brachte, ohne daß praktisch eine Einbuße an Genauigkeit auftrat.Zur Erläuterung der gewonnenen allgemeinen Rechenvorschriften wurden einige typische Beispiele behandelt, deren Ergebnisse als Charakteristikum der beim Kurzschluß in vermaschten, mehrfach gespeisten Netzen auftretenden Ausgleichsvorgängen die Tatsache erkennen lassen, daß der Ausgleichsstrom aus mehreren Wechselstromund Gleichstromgliedern besteht, die verschiedene Zeitkonstanten besitzen und sich auf die einzelnen Teile der Anordnung in verschiedener Weise vcrteilen. Im besonderen ergibt sich, daß die Zahl der Wechselstromglieder gleich der Zahl der nicht mehr zusammenfaßbaren Generatoren, und die Zahl der Gleichstromglieder gleich der Zahl der vom Kurzschlußort ausgehenden Stromwege mit verschiedenem Verhältnis von Selbstinduktion zu ohmschem Widerstand plus der Zahl der nicht mehr zusammenfaßbaren Kapazitäten ist. Ferner zeigt sich, daß sich die Stromglieder nicht notwendigerweise sämtlich addieren müssen, sondern daß sie auch teilweise in Opposition stehen können, so daß an manchen Stellen der Fall eintreten kann, daß der Gesamt-Wechselstromanteil oder -Gleichstromanteil anfänglich nur wenig abnimmt, konstant bleibt oder sogar anschwillt.Bemerkenswert ist ferner das Ergebnis, daß beim zweipoligen Kurzschluß im allgemeinen die gesunde Phase nur am Kurzschlußort frei von Überlagerungsströmen ist, während in den übrigen Teilen der Anordnungen auch in dieser Phase ein Überlagerungsstrom fließt, der jedoch ohne Stoßerscheinung von Null auf seinen Endwert anwächst.Dissertation des Verfassers, T. H. Berlin, Fakultät für Maschinenwesen. 相似文献
87.
88.
Sambor Grygorczuk Justyna Dunaj-Mayszko Piotr Czupryna Artur Sulik Kacper Toczyowski Agnieszka Siemieniako-Werszko Agnieszka ebrowska Sawomir Pancewicz Anna Moniuszko-Malinowska 《International journal of molecular sciences》2022,23(16)
Background: The detection rate of viral RNA in tick-borne encephalitis (TBE) is low and variable between studies, and its diagnostic/prognostic potential is not well defined. We attempted to detect RNA of TBE virus (TBEV) in body fluids of TBE patients. Methods: We studied 98 adults and 12 children with TBEV infection, stratified by the disease phase and presentation. EDTA blood and cerebrospinal fluid (CSF) samples were obtained upon hospital admission. RNA was extracted from freshly obtained plasma, concentrated leukocyte-enriched CSF, and whole blood samples, and real time PCR was performed with a Rotor-Gene Q thermocycler. Results: TBEV RNA was detected in (1) plasma of one (of the two studied) adult patients with an abortive infection, (2) plasma of two (of the two studied) adults in the peripheral phase of TBE, and (3) plasma and blood of an adult in the neurologic phase of TBE presenting as meningoencephalomyelitis. No CSF samples were TBEV RNA-positive. Conclusions: The detection of TBEV RNA in blood might be diagnostic in the peripheral phase of TBE. The lack of TBEV RNA in the CSF cellular fraction speaks against TBEV influx into the central nervous system with infiltrating leukocytes and is consistent with a relatively low intrathecal viral burden. 相似文献
89.
Monika Ku
nia Beata Zygmunt-Kowalska Artur Szajding Anna Magiera Rafa Stanik Maik Gude 《International journal of molecular sciences》2022,23(17)
The aim of the article is to compare two types of fly ash (from the fluidized and pulverized coal combustion process) as a filler for rigid polyurethane foam. Pulverized fly ash (PFA) is widely used in building materials, while fluidized fly ash (FFA) is not currently recycled, but landfilled. The produced rigid polyurethane foams were reinforced with 5 and 10% by weight addition of fly ash from two different types of boilers. The foaming process, physical properties, morphologies and thermal degradation were subject to comparative analysis. The research indicated that fly ash intensifies the reactions of foam synthesis, most commonly, polyurethane (PU) foam with an addition of 10% PFA. What is interesting is that both ashes can be used in PU foam technology as they do not cause deterioration of the physical parameters. As shown, the addition of filler affects the morphology and impairs the brittleness. Additionally, the use of fly ash from coal combustion in the technology of polyurethane materials complies with the guidelines of the circular economy stated in the European Union legislation. Partial replacement of petrochemical components with waste filler also reduces the total energy consumption in the production of PU composites. 相似文献
90.
Mariane Severino Mohammed Gagaoua Welder Baldassini Richard Ribeiro Juliana Torrecilhas Guilherme Pereira Rogrio Curi Luis Artur Chardulo Pedro Padilha Otvio Machado Neto 《International journal of molecular sciences》2022,23(20)
Proteomics has been widely used to study muscle biology and meat quality traits from different species including beef. Beef proteomics studies allow a better understanding of the biological processes related to meat quality trait determination. This study aimed to decipher by means of two-dimensional electrophoresis (2D-PAGE), mass spectrometry and bioinformatics the changes in post-mortem muscle with a focus on proteins differentially expressed in the Longissimus thoracis (LT) muscle of immunocastrated young heifers and steers. Carcass traits, chemical composition, pH, instrumental color (L*, a*, b*), cooking loss and Warner-Bratzler shear force (WBSF) of meat from F1 Montana-Nellore cattle were also evaluated. Backfat thickness (BFT) and intramuscular fat content (IMF) were 46.8% and 63.6% higher in heifers (p < 0.05), respectively, while evaporation losses (EL) were 10.22% lower compared to steers. No differences (p > 0.05) were observed for tenderness evaluated by WBSF (3, 10, and 17 days post-mortem), pH, and color traits (L*, a* and b*) between the experimental groups. The study revealed several proteins to be differentially expressed proteins in heifers compared steers (p < 0.05). In heifers, proteins involved in nutrient transport (TF, ALB, and MB), energy metabolism (ALDOA, GAPDH, and PKM), and oxidative stress and response to stress (HSPA8 and CA3) were associated with a greater BFT and IMF deposition. The higher expression of these proteins indicated greater oxidative capacity and lower glycolytic activity in the LT muscle of heifers. In steers, there was greater abundance of protein expression related to muscle contraction and proteins of structure (ACTA1, TPM2 and TNNT3), energy metabolism (ENO1, ENO3, PYGM, PGM1 and TPI1) and ATP metabolism (ATP5F1B, PEBP1 and AK1), indicating greater glycogenolysis in LT muscle, suggesting a shift in the glycolytic/oxidative fibers of steers. 相似文献