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101.
A grid of 50 dielectric sensors has been embedded in the walls of a mold to monitor resin transfer molding (RTM). The capacitance of each sensor increased as resin occupied the space between sensor plates, and it decreased with curing. Monitoring data can be used for process control to prevent dry spots and to determine when to de-mold the part. In previous studies, Skordos et al. [Skordos AA, Karkanas PI, Partridge IK. A dielectric sensor for measuring flow in resin transfer molding. Meas Sci Technol 2000;11:25–31] used a lineal sensor, Hegg et al. [Hegg MC, Ogale A, Mescher A, Mamishev AV, Minaie B. Remote monitoring of resin transfer molding processes by distributed dielectric sensors. J Compos Mater 2005;39(17)] used three large sensors. As experimentally shown in this study, these lineal or large-plate dielectric sensors may mislead since a sensor measures total fraction of the sensor’s plate area occupied by resin but not the resin’s whereabouts. To avoid ambiguity and yet maintain detailed monitoring, a sensor grid was made at the projections of embedded orthogonal electrodes. The developed sensor operation system eliminated tedious and costly manufacturing of conventionally shielded separate sensors. The success of the developed sensor system was demonstrated in RTM experiments. 相似文献
102.
Nicola Curreli Michele Serri Davide Spirito Emanuele Lago Elisa Petroni Beatriz Martín‐García Antonio Politano Bekir Gürbulak Songül Duman Roman Krahne Vittorio Pellegrini Francesco Bonaccorso 《Advanced functional materials》2020,30(13)
Layered semiconductors of the IIIA–VIA group have attracted considerable attention in (opto)electronic applications thanks to their atomically thin structures and their thickness‐dependent optical and electronic properties, which promise ultrafast response and high sensitivity. In particular, 2D indium selenide (InSe) has emerged as a promising candidate for the realization of thin‐film field effect transistors and phototransistors due to its high intrinsic mobility (>102 cm2 V?1 s?1) and the direct optical transitions in an energy range suitable for visible and near‐infrared light detection. A key requirement for the exploitation of large‐scale (opto)electronic applications relies on the development of low‐cost and industrially relevant 2D material production processes, such as liquid phase exfoliation, combined with the availability of high‐throughput device fabrication methods. Here, a β polymorph of indium selenide (β‐InSe) is exfoliated in isopropanol and spray‐coated InSe‐based photodetectors are demonstrated, exhibiting high responsivity to visible light (maximum value of 274 A W?1 under blue excitation 455 nm) and fast response time (15 ms). The devices show a gate‐dependent conduction with an n‐channel transistor behavior. Overall, this study establishes that liquid phase exfoliated β‐InSe is a valid candidate for printed high‐performance photodetectors, which is critical for the development of industrial‐scale 2D material‐based optoelectronic devices. 相似文献
103.
Whiting is a commercially important fish species of the world. This study demonstrates monthly variations in lipid and fatty acid (FA) contents of muscle, liver and roes of Black Sea whiting, Merlangius merlangus euxinus. Significant changes occurred in lipid contents between months (P < 0.05) with the highest values representing in liver 33.8–64.5%. Total polyunsaturated fatty acids (PUFA) in all groups were higher than total saturated and monounsaturated FAs with significant variations between months (P < 0.05). The highest PUFA of muscles, livers and roes were 60.0, 45.9 and 50.9%, respectively. The main FA was docosahexaenoic acid (DHA) of muscle tissue and roes, while oleic acid was the major FA in livers. Although about 164–357 g in muscle tissue or 224–392 g of whiting roe are necessary to consume to cover 1 g day?1 of eicosapentaenoic acid (EPA)+DHA for a healthy diet, only as low as 5.5–10.0 g of liver would be enough to cover the same amount of daily EPA+DHA requirement. The results indicated that whiting livers constitute a rich and underexploited source of polyunsatured FAs. Furthermore, the results may aid further research on the nutritional studies, the physiology and stock management of whiting species. 相似文献
104.
Turgay Seckin Süleyman Koytepe Ismail Özdemir Nevin Gürbüz Bekir Çetinkaya 《Journal of Inorganic and Organometallic Polymers and Materials》2004,14(3):177-190
Tricyclic heteroaraomatic dye-based monomer containing NMe2 units, 6-bis(dimethylamino)acridine(p-cymene)dichlororuthenium (II), was used to prepare novel polyimides via a one-stage solution polycondensation due to their stability under a variety of oxidative and reductive conditions. The Ru(II) complex monomer was synthesized starting from [RuCl2(p-cymene)]2 and 3,6-bis(dimethylamino)acridine. A series of stable polyimides was synthesized from the Ru(II) complex of 3,6-bis(dimethylamino)acridine and various aromatic dianhyrides. The polymers had inherent viscosities ranging from 1.72 to 2.11 dL/g and were soluble in polar solvents. The glass transition temperatures were 192–278 °C, and the 10% weight loss temperatures were above 503–635 °C. Ruthenium-substituted polyimides were tested for catalytic activity in the furan formation reaction of (Z)-3-methylpent-2-en-4-yn-1-ol. The polymeric catalyst was added to (Z)-3-methylpent-2-en-4-yn-l-ol without a solvent and the pure furan was isolated by distillation under reduced pressure. The conversion of the starting, enynol, was determined by gas chromatography (GC). 相似文献
105.
Bekir Dizioĝlu 《Forschung im Ingenieurwesen》1988,54(2):53-66
Zusammenfassung Die allgemeine zwangl?ufige r?umliche Bewegung eines starren K?rpers ist durch die relative Schrotbewegung der Gangaxoide
auf der Rastaxoide gegeben. Diese Achsenfl?chen berühren sich l?ngs der momentanen Schraubenachse der Bewegung. Mit den Methoden
der kinematischen Geometrie werden die gegenseitigen Bewegungen dieser Axoiden eingehend er?rtert. Au?erdem sind drei neuartige
Grundaufgaben der r?umlichen Getriebelehre formuliert. Es wird die Ermittlung der W?lzfl?chen bei einer bekannten charakteristischen
Kurve angegeben. 相似文献
106.
Bekir Sami Yilbas 《International Journal of Heat and Mass Transfer》2003,46(18):3511-3520
Laser shortpulse heating of metallic substrates requires microscopic examination of the energy transport in the irradiated region. This is because of low specific heat capacity of electrons, which results in nonequilibrium temperature distribution in this region. In the present study, laser shortpulse heating of gold with variable properties is considered. Nonequilibrium energy transport is modelled using an electron kinetic theory approach. The resulting integro-differential equations are reduced to partial differential equation using a Fourier transform method. The resulting differential equation is further transformed into two differential equations similar to those given in the two-equation model. The coefficients of the differential equations are correlated. It is found that variable properties results in higher lattice site and lower electron temperatures as compared to those corresponding to constant properties case. 相似文献
107.
Zur Theorie der ebenen unveränderlichen Systeme—ein Beitrag zur Getriebelehre und Konstruktionslehre
Prof. em. Dr.-Ing. Bekir Dizioĝlu 《Forschung im Ingenieurwesen》1989,55(3):88-95
Zusammenfassung Auf im wesentlichen analytischem Weg wird eine Reihe von S?tzen über Rückkehrpole und Rückkehrkreise, über Wendepole und Wendekreise
abgeleitet. Die Grundlage der gesamten Betrachtung bildet die Ableitung der nten Evolutengleichung der Einhüllenden einer
geraden Linie. Diese Ableitung kann allgemein aufgestellt werden. Die abgeleiteten S?tze werden auf das Problem der angen?herten
Geradführung angewendet. 相似文献
108.
Properties of concretes produced with waste concrete aggregate 总被引:5,自引:0,他引:5
An environmentally friendly approach to the disposal of waste materials, a difficult issue to cope with in today's world, would only be possible through a useful recycling process. For this reason, we suggest that clearing the debris from destroyed buildings in such a way as to obtain waste concrete aggregates (WCA) to be reused in concrete production could well be a partial solution to environmental pollution. For this study, the physical and mechanical properties along with their freeze-thaw durability of concrete produced with WCAs were investigated and test results presented. While experimenting with fresh and hardened concrete, mixtures containing recycled concrete aggregates in amounts of 30%, 50%, 70%, and 100% were prepared. Afterward, these mixtures underwent freeze-thaw cycles. As a result, we found out that C16-quality concrete could be produced using less then 30% C14-quality WCA. Moreover, it was observed that the unit weight, workability, and durability of the concretes produced through WCA decreased in inverse proportion to their endurance for freeze-thaw cycle. 相似文献
109.
Turgay Seckin Süleyman Koytepe Ismail Özdemir Nevin Gürbüz Bekir Çetinkaya 《Journal of Inorganic and Organometallic Polymers》2004,14(3):177-190
Tricyclic heteroaraomatic dye-based monomer containing NMe2 units, 6-bis(dimethylamino)acridine(p-cymene)dichlororuthenium (II), was used to prepare novel polyimides via a one-stage solution polycondensation due to their stability under a variety of oxidative and reductive conditions. The Ru(II) complex monomer was synthesized starting from [RuCl2(p-cymene)]2 and 3,6-bis(dimethylamino)acridine. A series of stable polyimides was synthesized from the Ru(II) complex of 3,6-bis(dimethylamino)acridine and various aromatic dianhyrides. The polymers had inherent viscosities ranging from 1.72 to 2.11 dL/g and were soluble in polar solvents. The glass transition temperatures were 192–278 °C, and the 10% weight loss temperatures were above 503–635 °C. Ruthenium-substituted polyimides were tested for catalytic activity in the furan formation reaction of (Z)-3-methylpent-2-en-4-yn-1-ol. The polymeric catalyst was added to (Z)-3-methylpent-2-en-4-yn-l-ol without a solvent and the pure furan was isolated by distillation under reduced pressure. The conversion of the starting, enynol, was determined by gas chromatography (GC). 相似文献
110.
The bleeding of concrete and the evaporation of water from the surface of concrete, which affect plastic shrinkage cracking, were investigated. The quantities of water evaporated from concrete specimens exposed to different temperatures, relative humidities and windy conditions were evaluated. The evaporation of water from the surface of C25 and C35 concretes, which were made using PKC/B 32.5R and PC 42.5 cements, was determined. It was observed that the cement type affects the bleeding of concrete. Also concrete mixes containing high cement contents yielded minimum quantities of bleeding. It was observed that concrete mixes containing more mixing water yielded the maximum amount of water evaporation. 相似文献