Growth of thin graphene layers on stacked SiC surface in ultra high vacuum

We demonstrate a technique to produce thin graphene layers on C-face of SiC under ultra high vacuum conditions. A stack of two SiC substrates comprising a half open cavity at the interface is used to partially confine the depleted Si atoms from the sample surface during the growth. We observe that this configuration significantly slows the graphene growth to easily controllable rates on C-face SiC in UHV environment. Results of low-energy electron diffractometry and Raman spectroscopy measurements on the samples grown with stacking configuration are compared to those of the samples grown by using bare UHV sublimation process

The comparison of transient photocurrent spectroscopy measurements of Pulsed Electron Deposited ZnO thin film for air and vacuum ambient conditions

WOS: 000467389900007Photoconduction mechanism of ZnO thin films that produced by Pulsed Electron Deposition method is systematically investigated by taking Transient Photocurrent Spectroscopy measurements for different atmospheres including high vacuum and air environments. Response and recovery rates of photocurrent in the air are faster than the rates in high vacuum condition. The results in the presented work clearly indicate that the photoconduction of ZnO thin films with high surface-area-to-volume ratio are surface-related and mostly governed by adsorption/desorption of oxygen and water molecules in the atmosphere. Therefore, the high surface interaction tendency of ZnO surface with the atmosphere inevitably leads to charge transfer from surface to adsorbates and/or vice versa.Scientific and Technological Research Council of Turkey (TUBITAK) under BIDEB-2232 Program [117C032]; Ege University Scientific Research Project (BAP)Ege University [15-FEN-058]The authors would like to thank Center for Materials Research (MAM) of Izmir Institute of Technology, Central Research Test and Analysis Laboratory Application and Research Center (EGE-MATAL) of Ege University and Central Research Laboratories of Izmir Katip Celebi University for characterizations of samples. This work has been partially supported by the Scientific and Technological Research Council of Turkey (TUBITAK) under BIDEB-2232 Program with Project No. 117C032 and Ege University Scientific Research Project (BAP) with Project No. 15-FEN-058

Added Value of Contrast Medium in Whole-Body Hybrid Positron Emission Tomography/Magnetic Resonance Imaging: Comparison between Contrast-Enhanced and Non-Contrast-Enhanced Protocols.

To compare the diagnostic ability and time efficiency of contrast-enhanced (CE) whole body fluorodeoxyglucose (FDG) positron emission tomography/magnetic resonance imaging (PET/MRI) protocol and non-CE (NCE) protocol

Primary renal angiosarcoma with progressive clinical course despite surgical and adjuvant treatment: A case report

WOS: 000351631900084Angiosarcoma is an extremely rare, high-grade malignancy, which accounts for <2% of all soft-tissue sarcomas. Cases of primary renal angiosarcoma represent 1% of these. Angiosarcomas involving the kidney usually originate from metastatic skin lesions or primary visceral lesions and most often occur in the sixth and seventh decades of life. The present study describes a case of primary renal angiosarcoma that presented as a large right-sided renal mass with symptoms of flank pain. Despite surgical removal of the tumor, recurrent disease with associated lung metastases was identified at the surgical site following adjuvant chemotherapy. The patient succumbed to the disease 13 months after the diagnosis

Process matchmaking on a p2p environment

A process matchmaking environment based on P2P architecture and Gnutella protocol is established Java Agent Development Framework (JADE) is used as middleware. The processes are modeled as one-input transition systems augmented by goal state descriptions. A polynomial-time algorithm for handling matchmaking of peer process encounters is developed The environment can easily be customized to a specific application domain by simple user-interface modifications and through the development of related state ontologies

Effects Of Different Luting Cements And Light Curing Units On The Sealing Ability And Bond Strength Of Fiber Posts

This study evaluated the sealing ability and push-out bond strength of two luting cements cured with two different types of light curing units (LCU): light-emitting diode (LED) versus quartz tungsten halogen (QTH). Forty teeth were divided into four groups (n=10/group). Quartz fiber posts (D.T. Light-Post) were luted to coronal or apical section of root canals using two types of resin cements (Panavia F or RelyX) cured with either LED LCU (Elipar FreeLight II) or QTH LCU (Optilux 501). Highest push-out bond strength was exhibited by QTH-cured RelyX, which was not significantly different from LED-cured RelyX but was higher than QTH-cured Panavia F. The push-out bond strength of Panavia F did not differ with LCU type (p>0.05), but exhibited lower values than both QTH- and LED-cured RelyX. Fluid filtration test revealed that sealing ability was not influenced by luting cement type, but was significantly influenced by LCU type in favor of QTH light source: QTH-cured specimens displayed better seal than LED-cured ones (p<0.05).WoSScopu

Control of the graphene growth rate on capped SiC surface under strong Si confinement

The effect of the degree of Si confinement on the thickness and morphology of UHV grown epitaxial graphene on (0 0 0 −1) SiC is investigated by using atomic force microscopy and Raman spectroscopy measurements. Prior to the graphene growth process, the C-face surface of a SiC substrate is capped by another SiC comprising three cavities on its Si-rich surface with depths varying from 0.5 to 2 microns. The Si atoms, thermally decomposed from the sample surface during high temperature annealing of the SiCcap/SiCsample stack, are separately trapped inside these individual cavities at the sample/cap interface. Our analyses show that the growth rate linearly increases with the cavity height. It was also found that stronger Si confinement yields more uniform graphene layers

Added Value of Contrast Medium in Whole-Body Hybrid Positron Emission Tomography/Magnetic Resonance Imaging: Comparison between Contrast-Enhanced and Non-Contrast-Enhanced Protocols

Objective: To compare the diagnostic ability and time efficiency of contrast-enhanced (CE) whole body fluorodeoxyglucose (FDG) positron emission tomography/magnetic resonance imaging (PET/MRI) protocol and non-CE (NCE) protocol. Subjects and Methods: Ninety-three patients with known primary tumors underwent whole-body hybrid FDG PET/MRI during the follow-up of their malignancies with the use of NCE and CE protocols. The NCE PET/MRI protocol consisted of diffusion-weighted (b = 0 and 800 s/mm(2)) and T1-weighted Turbo Flash in the axial plane and T2-weighted HASTE sequence in the coronal planes (sigma = 25 min). The CE PET/MRI protocol was performed by acquiring axial serial CE 3D FS VIBE images in the upper abdomen, completing the whole body in the late phase in the axial plane (sigma = 30 min). Results: There was a statistically significant difference between the total number of lesions detected by the CE protocol (median 2, interquartile range (IQR) 0-14) and that detected by the NCE protocol (median 1, IQR 0-5; p < 0.001). More malignancies were detected in the abdomen (p < 0.001) and brain (p < 0.001) with the CE PET/MRI protocol, whereas no significant difference was present when comparing the 2 protocols in the detection of malignancies in the head and neck (p = 0.356), thorax (p = 0.09), lymph nodes (p = 0.196), and bone (p = 0.414). Conclusion: The CE FDG PET/MRI protocol enables fast and accurate detection of malignancies compared to the NCE FDG PET/MRI protocol, particularly in the upper abdomen and brain. Diagnostic ability and time efficiency can be increased with the proposed short CE protocol in place of the whole body PET/MRI protocol including both NCE and CE imaging sequences