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11.
A. Ngamjarurojana S. Ural S.H. Park S. Ananta R. Yimnirun K. Uchino 《Ceramics International》2008,34(4):705-708
In this study, in order to develop low-temperature sintering ceramics for a multilayer piezoelectric transformer application, we explored CuO and Bi2O3 as sintering aids at low temperature (900 °C) sintering condition for Sb, Li and Mn-substituted 0.8Pb(Zr0.48Ti0.52)O3–0.16Pb(Zn1/3Nb2/3)O3–0.04Pb(Ni1/3Nb2/3)O3 ceramics. These substituted ceramics have excellent piezoelectric and dielectric properties such as d33 347 pC/N, kp 0.57 and Qm 1469 when sintered at 1200 °C. The addition of CuO decreased the sintering temperature through the formation of a liquid phase. However, the piezoelectric properties of the CuO-added ceramics sintered below 900 °C were lower than the desired values. The additional Bi2O3 resulted in a significant improvement in the piezoelectric properties. The composition Sb, Li and Mn-substituted 0.8Pb(Zr0.48Ti0.52)O3–0.16Pb(Zn1/3Nb2/3)O3–0.04Pb(Ni1/3Nb2/3)O3 + 0.5 wt% CuO + 0.5 wt% Bi2O3 showed the value of kp = 0.56, Qm = 1042 (planar mode), d33 = 350 pC/N, when it was sintered at 900 °C for 2 h. These values indicated that the newly developed composition might be suitable for multilayer piezoelectric transformer application. 相似文献
12.
Evran E. Ural Victoria Toomajian Ehsanul Hoque Apu Mladen Veletic Ilangko Balasingham Nureddin Ashammakhi Masamitsu Kanada Christopher H. Contag 《International journal of molecular sciences》2021,22(9)
Extracellular vesicles (EVs) are cell-derived nanostructures that mediate intercellular communication by delivering complex signals in normal tissues and cancer. The cellular coordination required for tumor development and maintenance is mediated, in part, through EV transport of molecular cargo to resident and distant cells. Most studies on EV-mediated signaling have been performed in two-dimensional (2D) monolayer cell cultures, largely because of their simplicity and high-throughput screening capacity. Three-dimensional (3D) cell cultures can be used to study cell-to-cell and cell-to-matrix interactions, enabling the study of EV-mediated cellular communication. 3D cultures may best model the role of EVs in formation of the tumor microenvironment (TME) and cancer cell-stromal interactions that sustain tumor growth. In this review, we discuss EV biology in 3D culture correlates of the TME. This includes EV communication between cell types of the TME, differences in EV biogenesis and signaling associated with differing scaffold choices and in scaffold-free 3D cultures and cultivation of the premetastatic niche. An understanding of EV biogenesis and signaling within a 3D TME will improve culture correlates of oncogenesis, enable molecular control of the TME and aid development of drug delivery tools based on EV-mediated signaling. 相似文献
13.
The objective of testing is to determine whether an implementation under test conforms to its specification. In distributed
test architectures involving multiple remote testers, this objective can be complicated by the fact that testers may encounter
coordination problems relating to controllability (synchronization) and observability during the application of tests. Based
on a finite state machine (FSM) specification of the externally observable behaviour of a distributed system and a distinguishing
sequence, this paper proposes a method for constructing a checking sequence where there is no potential controllability or
observability problems, and where the use of external coordination message exchanges among testers is minimized. The proposed
method does not assume a reliable reset feature in the implementations of the given FSM to be tested by the resulting checking
sequence.
phone: 613-562-5800(Extn)6684
Received May 2004
Revised March 2005
Accepted April 2005 by J. Derrick, M. Harman and R. M. Herons 相似文献
14.
Electroinitiated cationic copolymerizations of indene-4-methoxystyrene and indene-β-bromostyrene monomer couples were investigated in dichloromethane by constant potential electrolysis. Copolymer compositions were determined by i.r. spectroscopy and reactivity ratios for the monomers were calculated according to integrated Lewis-Mayo equation. The composition of copolymers and the reactivity ratios were discussed in terms of anodic peak potentials of monomers. 相似文献
15.
This paper assesses the use of Chandy and Lamport's distributed snapshots algorithm (DSA) for stabilizing a communication protocol, a special type of distributed system. We show that when a loss of coordination occurs during the distributed execution of the protocol, DSA is not guaranteed to terminate, and therefore it sometimes fails to obtain a global state or snapshot. We propose some modifications to DSA to solve this problem. Finally, we discuss how, in the case of a loss of coordination, the modified algorithm can be used to stabilize a communication protocol, and we assess the suitability of the global state obtained by DSA as a recovery point to be used later in a backward recovery procedure. 相似文献
16.
Yavuz Akbulut Ömer UysalAuthor VitaeHatice Ferhan OdabasiAuthor Vitae Abdullah KuzuAuthor Vitae 《Computers & Education》2008
This study administered the unethical computer using behavior scale (UECUBS) developed by [Namlu, A.G., & Odabasi, F. (2007). Unethical computer using behavior scale: A study of reliability and validity on Turkish university students. Computers and Education, 48, 205–215.] to investigate whether gender, program of study and PC experience have an impact on ethical judgments of undergraduate students regarding information and communication technologies (ICTs). The sample consisted of 559 undergraduates from the Education Faculty of the most populated state university in Turkey. The results of 5 (program of study) × 2 (gender) × 2 (PC experience) between-groups analysis of variance (ANOVA) indicated no significant differences among different programs of study and between high and low experienced PC users. The analysis showed significant differences between males and females. A significant interaction between the program of study and gender was found, which indicated that the difference between males and females did not follow a similar pattern across different programs of study. More specifically, females’ ethical judgments were consistent across different fields while males’ judgments varied according to the field of study. 相似文献
17.
18.
Hydrogenated amorphous silicon oxygen alloy thin films (a-SiOx:H) were prepared on glass and crystalline silicon substrates, with two different oxygen contents: x = 0.15 and x = 0.32. The deposition was realized in an RF-PECVD reactor by using the plasma of the gas mixture SiH4 and CO2 with tunable flow rates. The optical characterization data of the single layers were received from the optical transmittance experiments. Multilayered samples were designed upon the results of the single layers. In depositing the multilayers the repetition of the a-SiO0.15:H/a-SiO0.32:H kernel-pair was used. The samples were prepared as 25-pair of λ/4 layers, 3-pair of λ/4 layers and 3-pair of λ/2 layers. The inner morphologies and nanostructural contents of the films were investigated by Small-Angle X-ray Scattering (SAXS) method. 相似文献
19.
In this study, some probiotic characteristics such as antimicrobial activity, vancomycin resistance, growth ability at pH, resistance to bile salts, bile salt deconjugation and hydrophobicity of 30 Enterococcus faecium and Enterococcus durans strains isolated and identified from raw milk and various dairy products were investigated. According to the study results, antimicrobial activity profiling, pH and bile salt resistance and bile salt deconjugation ability of Enterococcus strains varied depending on the species and strains and all the strains showed resistance to the tested bile salt concentrations. It was concluded that the E. faecium and E. durans strains tested showed probiotic characteristics and have the potential to be used in food production. 相似文献
20.
S Kü?üko?lu E Ural H Mutlu D Ural B S?nmez S Uner 《Canadian Metallurgical Quarterly》1997,10(8):862-865
This report describes a case of right coronary sinus of Valsalva aneurysm which ruptured into the left ventricle. The diagnosis was made with two-dimensional transthoracic echocardiography which showed an abnormal structure extending from the aortic root into the left ventricle adjacent to the interventricular septum. Subsequent examinations with transesophageal echocardiography and aortic root angiography and surgical findings confirmed the diagnosis of transthoracic echocardiography. The patient underwent aortic valve replacement. At follow-up 12 months later, the patient was without symptoms and repeated echocardiographic examinations showed no recurrence. 相似文献