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111.
Encapsulation of organic light-emitting devices by means of photopolymerized polyacrylate films 总被引:2,自引:0,他引:2
For encapsulation of organic light-emitting devices (OLEDs) built on glass substrate, photopolymerizable blend consists of pentaerythritol triacrylate (PETIA) and HSP188 (photoinitiator) was spin-coated onto an OLED and then cured to form a cross-linked passivation layer. The electroluminescence (EL) and the rate of degradation were examined to compare the electrical and the emissive properties of the device before and after forming the passivation layer. In this case, wet process encapsulation, which did not influence the EL characteristic of the device, enhanced the lifetime of the device in air. 相似文献
112.
113.
Min Han Ki Choi Gi Seob Jung Jong An Yang In Young 《Journal of Mechanical Science and Technology》2003,17(7):958-965
Structural integrity of either a passenger car or a light truck is one of the basic requirements for a full vehicle engineering
and development program. The results of the vehicle product performance are measured in terms of ride and handling, durability,
noise/vibration/harshness (NVH), crashworthiness and occupant safety. The level of performance of a vehicle directly affects
the marketability, profitability and, most importantly, the future of the automobile manufacturer. In this study, we used
the virtual proving ground (VPG) approach for obtaining the dynamic characteristics. The VPG approach uses a nonlinear dynamic
finite element code (LS-DYNA3D) which expands the application boundary outside the classic linear static assumptions. The
VPG approach also uses realistic boundary conditions of tire/road surface interactions. To verify the predicted dynamic results,
a single lane change test has been performed. The prediction results were compared with the experimental results, and the
feasibility of the integrated CAE analysis methodology was verified. 相似文献
114.
In order to elucidate the relationship between the chemically similar chalcogen elements S, Se, Te, and 210Po in marine invertebrates, we conducted a comparative study of the distribution patterns of these elements in a squid, Todarodes pacificus. Elemental concentrations of the four chalcogens were determined in (mantle) muscle, gill, stomach, and hepatopancreas tissues. No relationship between chalcogen concentrations and morphological parameters (mantle length, body weight, and sex) was evident. Gills showed slightly elevated levels of Se and 210Po, which may indicate absorption and uptake of these elements over the gill surface. All four chalcogens have their highest concentrations in the hepatopancreas and the lowest concentrations in the muscle tissue. However, concentration differences between tissues, revealed by (1) bioaccumulation values based on reference seawater values and (2) internal relative enrichment factors (IREF) based on enrichment of hepatopancreas compared to muscle tissue, were least pronounced for S, most distinct for 210Po, and moderate for Se and Te. Furthermore, no significant correlation for Se, Te, and 210Po with S within tissue concentrations, and only a slightly negative correlation between S and 210Po in the squid muscle and hepatopancreas tissues were found, which indicates either an antagonistic effect between, or a disconnection of the two elements through metabolic processing. Overall, the distribution patterns of Se and Te resemble those of essential trace elements, such as Zn and Cu, whereas 210Po is partitioned in a manner similar to toxic heavy metals, such as Cd and Ag. 相似文献
115.
The consumption of LNG (Liquefied Natural Gas) has recently increased due to a substantial rise in the price of petroleum. One of the major carriers of LNG is the LNG ships whose containment systems are composed of corrugated stainless steel plates (primary barriers) and glass fabric composite sandwich constructions (secondary barriers). The primary barriers are constructed by welding many corrugated thin stainless steel plates to reduce thermal stress, while the secondary barriers are constructed by adhesively bonding glass fabric composite sandwich constructions.One of the key technologies for the secondary barriers is to thoroughly seal the adhesive joining area, which can retard LNG leakage when the primary barriers are failed. The sealing quality of the adhesive joint is dependent on the wetting characteristics between the sandwich constructions and adhesive, which is in turn dependent on the curing cycle for the adhesive.In this work, a new method to measure the gas leakage of adhesively bonded joint was devised. The adhesive joint specimens were prepared under several different curing cycles to investigate the impregnation of adhesive into the glass fabric composite. Also, the thermal residual stress in the adhesive joint was estimated by the double strip deformation experiment. Finally, an improved curing method was developed with high tightness of the secondary barriers without increase of thermal residual stress. 相似文献
116.
Kai Zhang Mihui Park Limin Zhou Gi‐Hyeok Lee Weijie Li Yong‐Mook Kang Jun Chen 《Advanced functional materials》2016,26(37):6728-6735
Urchin‐like CoSe2 assembled by nanorods has been synthesized via simple solvothermal route and has been first applied as an anode material for sodium‐ion batteries (SIBs) with ether‐based electrolytes. The CoSe2 delivers excellent sodiation and desodiation properties when using 1 m NaCF3SO3 in diethyleneglycol dimethylether as an electrolyte and cycling between 0.5 and 3.0 V. A high discharge capacity of 0.410 Ah g?1 is obtained at 1 A g?1 after 1800 cycles, corresponding to a capacity retention of 98.6% calculated from the 30th cycle. Even at an ultrahigh rate of 50 A g?1, the capacity still maintains 0.097 Ah g?1. The reaction mechanism of the as‐prepared CoSe2 is also investigated. The results demonstrate that at discharged 1.56 V, insertion reaction occurs, while two conversion reactions take place at the second and third plateaus around 0.98 and 0.65 V. During the charge process, Co first reacts with Na2Se to form NaxCoSe2 and then turns back to CoSe2. In addition to Na/CoSe2 half cells, Na3V2(PO4)3/CoSe2 full cell with excessive amount of Na3V2(PO4)3 has been studied. The full cell exhibits a reversible capacity of 0.380 Ah g?1. This work definitely enriches the possibilities for anode materials for SIBs with high performance. 相似文献
117.
Transformer‐Reuse Reconfigurable Synchronous Boost Converter with 20 mV MPPT‐Input, 88% Efficiency,and 37 mW Maximum Output Power
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This paper presents a transformer‐based reconfigurable synchronous boost converter. The lowest maximum power point tracking (MPPT)‐input voltage and peak efficiency of the proposed boost converter, 20 mV and 88%, respectively, were achieved using a reconfigurable synchronous structure, static power loss minimization design, and efficiency boost mode change (EBMC) method. The proposed reconfigurable synchronous structure for high efficiency enables both a transformer‐based self‐startup mode (TSM) and an inductor‐based MPPT mode (IMM) with a power PMOS switch instead of a diode. In addition, a static power loss minimization design, which was developed to reduce the leakage current of the native switch and quiescent current of the control blocks, enables a low input operation voltage. Furthermore, the proposed EBMC method is able to change the TSM into IMM with no additional time or energy loss. A prototype chip was implemented using a 0.18‐μm CMOS process, and operates within an input voltage range of 9 mV to 1 V, and an output voltage range of 1 V to 3.3 V, and provides a maximum output power of 37 mW. 相似文献
118.
A loss of subchannel orthogonality due to time-variant multipath channels in orthogonal frequency division multiplexing (OFDM) systems leads to interchannel interference (ICI) which increases the error floor in proportion to the Doppler frequency. A simple frequency-domain equalization technique which can compensate for the effect of ICI in a multipath fading channel is proposed. In this technique, the equalization of the received OFDM signal is achieved by using the assumption that the channel impulse response (CIR) varies in a linear fashion during a block period and by compensating for the ICI terms that significantly affect the bit-error rate (BER) performance 相似文献
119.
Indirect Cutting Force Measurement Considering Frictional Behaviour in a Machining Centre Using Feed Motor Current 总被引:1,自引:1,他引:0
Gi D. Kim Chong N. Chu 《The International Journal of Advanced Manufacturing Technology》1999,15(7):478-484
In machine tools, friction exists between the table and the guideways, and in ballscrews. In this paper, feed motor current
is measured by a hall effect current sensor. It is used to calculate the motor torque which, in turn, is the frictional torque
at steady state. Some frictional phenomena are studied in feed drive systems of a horizontal machining centre, such as the
relationship between feedrate and frictional torque, the relationship between frictional torque and table feed position, and
the slideway cover effects on frictional torque. Considering all these frictional phenomena, the relationship between the
feed force and the feed motor current is obtained. Feed force can be estimated well from the feed motor current considering
frictional behaviour. The relationship between the cutting force and the feed motor current is slightly different during up
milling and down milling, because y(vertical) directional cutting force changes the frictional force. 相似文献
120.
Hye Eun Lee Min Kyo Jung Seul Gi Noh Hye Bin Choi Se hyun Chae Jae Hyeok Lee Ji Young Mun 《International journal of molecular sciences》2021,22(21)
Iron overload in the brain, defined as excess stores of iron, is known to be associated with neurological disorders. In neurodegeneration accompanied by brain iron accumulation, we reported a specific point mutation, c.974-1G>A in WD Repeat Domain 45 (WDR45), showing iron accumulation in the brain, and autophagy defects in the fibroblasts. In this study, we investigated whether fibroblasts with mutated WDR45 accumulated iron, and other effects on cellular organelles. We first identified the main location of iron accumulation in the mutant fibroblasts and then investigated the effects of this accumulation on cellular organelles, including lipid droplets, mitochondria and lysosomes. Ultrastructure analysis using transmission electron microscopy (TEM) and confocal microscopy showed structural changes in the organelles. Increased numbers of lipid droplets, fragmented mitochondria and increased numbers of lysosomal vesicles with functional disorder due to WDR45 deficiency were observed. Based on correlative light and electron microscopy (CLEM) findings, most of the iron accumulation was noted in the lysosomal vesicles. These changes were associated with defects in autophagy and defective protein and organelle turnover. Gene expression profiling analysis also showed remarkable changes in lipid metabolism, mitochondrial function, and autophagy-related genes. These data suggested that functional and structural changes resulted in impaired lipid metabolism, mitochondrial disorder, and unbalanced autophagy fluxes, caused by iron overload. 相似文献