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91.
Imène Lahouij Fabrice Dassenoy Ludvig de Knoop Jean-Michel Martin Béatrice Vacher 《Tribology Letters》2011,42(2):133-140
Inorganic fullerene-(IF)-like nanoparticles made of metal dichalcogenides (IF-MoS2, IF-WS2) have been known to be effective as anti-wear and friction modifier additives under boundary lubrication. The lubrication
mechanism of these nanoparticles has been widely investigated in the past and even if the exfoliation and third body transfer
of molecular sheets onto the asperities constitute the prevalent mechanism for the improved tribological behavior of IF nanoparticles,
it has also been suggested that a rolling friction process could also play a role for well crystallized and spherical particles.
In this study, in situ Transmission Electron Microscopy (TEM) observations of the behavior of single IF-MoS2 nanoparticles were conducted using a sample holder that combines TEM and Atomic Force Microscopy (AFM) which simultaneously
can apply normal and shear loads. It was shown that depending on the test conditions, either a rolling process or a sliding
of the fullerenes could be possible. These in situ TEM observations are the first carried out with IF nanoparticles. 相似文献
92.
93.
A PbS-sensitized photovoltaic photodetector responsive to near-infrared (NIR) light was fabricated by depositing monolayered PbS nanoparticles on a mesoporous TiO(2) (mp-TiO(2)) film via the spin-assisted successive ionic layer adsorption and reaction (SILAR) method. By adjusting the size and morphology of the PbS nanoparticles through repeated spin-assisted SILAR cycles, the PbS-sensitized photovoltaic photodetector achieved an external quantum efficiency of 9.3% at 1140 nm wavelength and could process signals up to 1 kHz. 相似文献
94.
Ad hoc networks have a scalability problem. When the nodes of an ad hoc network increase in number or mobility, the amount
of control traffic for routing increases and could cause traffic congestion. Cluster-based routing schemes have been proposed
as a solution to this problem. Typical cluster-based ad hoc networks use a proactive routing scheme for intra-cluster routes
and a reactive routing scheme for inter-cluster routes. In this study, we propose a new cluster-based routing scheme for ad
hoc networks which makes use of the mobility of nodes. Nodes are divided into two groups on the basis of their mobility. For
a route search within a cluster, a proactive routing scheme is used for low-mobility nodes and a flooding-based reactive routing
scheme is used for high-mobility nodes. The required control traffic of the proposed scheme is analyzed and optimal parameters
of the proposed scheme are derived from the analysis. The numerical results show that the proposed scheme produces far less
control traffic than a typical cluster-based routing scheme. 相似文献
95.
Donghyun Kim Jaewook Jeong Hwarim Im Sungmo Ahn Heonsu Jeon Changhee Lee Yongtaek Hong 《Organic Electronics》2011,12(11):1841-1845
Vertical organic field-effect transistors (VOFETs) with nanoscale channel openings have been fabricated using pentacene as an active layer material. To achieve uniform nanoscale two-dimensional channel openings, a laser holography lithography has been introduced. Uniformly distributed and well-aligned holes with 250 nm diameter were successfully obtained with the laser holography lithography. VOFET devices with these channel openings have shown high on/off ratio of about 103 without any further treatment. Gate leakage current was also decreased with an additional insulating layer generated on the gate electrode sidewall via plasma oxidation. 相似文献
96.
97.
Photo‐Stable Organic Thin‐Film Transistor Utilizing a New Indolocarbazole Derivative for Image Pixel and Logic Applications
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Ji Hoon Park Hee Sung Lee Soohyung Park Sung‐Wook Min Yeonjin Yi Cheon‐Gyu Cho Jiwon Han Tae Woong Kim Seongil Im 《Advanced functional materials》2014,24(8):1109-1116
Small molecule pentacene layer has been a representative among many organic thin‐film transistor (OTFT) channels with decent p‐type mobilities, but it is certainly light‐sensitive due to its relatively small highest occupied molecular orbital‐lowest unoccupied molecular orbital (HOMO‐LUMO) gap (1.85 eV). Although a few other small molecule‐based layers have been reported later, their photo‐stabilities or related device applications have hardly been addressed. Here, a new photostable organic layer is reported, heptazole (C26H16N2), which has almost the same HOMO level as that of pentacene but with a higher HOMO‐LUMO gap (≈2.95 eV). This heptazole OTFT displays a decent mobility comparable to that of conventional amorphous Si TFTs, showing good photostability unlike pentacene OTFTs. An image pixel driving the photostable heptazole OTFT connected to a pentacene/Al Schottky photodiode is demonstrated. This heptazole OTFT also conveniently forms a logic inverter coupled with a pentacene OTFT, sharing Au for source/drain. 相似文献
98.
David K. Hsu Kwang-Hee Im Young-Tae Cho Jae-Woung Park Jae-Ki Sim In-Young Yang 《Journal of Mechanical Science and Technology》2002,16(3):292-301
Ultrasound waves interact strongly with the orientation and sequence of the plies in a layup when propagating in the thickness direction of composite laminates. Also the layup orientation greatly influences its properties in a composite laminate. If the layup orientation of a ply is misaligned, it could result in the part being rejected and discarded. Now, most researchers cut a small coupon from the waste edge and use a microscope to optically verify the ply sequences on important parts. This may add a substantial cost to the production since the test is both labor intensive and performed after the part is cured. A nondestructive technique would be very beneficial, which could be used to test the part after curing and requires less time than the optical test. Therefore we have developed, reduced, and implemented a novel ply-by-ply vector decomposition model for composite laminates fabricated from unidirectional plies. This model decomposes the transmission of a linearly polarized ultrasound wave into orthogonal components through each ply of a laminate. High probability is found, by comparisons between the model and tests, in characterizing cured layups of the laminates by using the proposed method. 相似文献
99.
100.
We have evaluated a multichannel transcranial magnetic stimulation (TMS) system using realistic simulations based on the boundary element method (BEM). We investigated various configurations and types of stimulation coils by means of quantitative measures such as targeting accuracy and field concentration. The simulation studies applied to four different head-brain models suggest improved coil types yielding enhanced targeting accuracy and concentrated evoked electric field distribution 相似文献